Monthly Archives: February 2020

Collision Tumor of a Squamous Cell Carcinoma and Adenoid Cystic Carcinoma in Mobile Tongue

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DOI: 10.31038/JCRM.2020311

Abstract

Malignant neoplasms in tongue are mainly squamous cell carcinomas (SCCs). Adenoid cystic carcinoma (AdCC) in mobile tongue is extremely rare, with a reported incidence of approximately 3%. Here we report a collision tumor of SCC and AdCC in an 88-year-old female with an ulcerative white lesion on the left lateral tongue. A computed tomography scan of the neck demonstrated a 2.0 cm mass with 0.6 cm radiologic depth of invasion. Complete examination of the lesion demonstrated a collision tumor consisting of SCC and AdCC which were close to each other but clearly separated. Histomorphological and immunohistochemical studies confirmed the two distinct tumor entities. To our knowledge, this is the first case of collision tumor of SCC and AdCC in the mobile tongue in which two distinct carcinoma entities were identified in this lesion. A diagnosis of this collision tumor can only be reached by complete histological examination of the lesion after surgical resection. Surgery is the choice of the treatment. Both tumor types need to be considered for therapeutic strategy and long-term follow-up is mandatory.

Keywords

Collision tumor, squamous cell carcinoma, adenoid cystic carcinoma, mobile tongue

Introduction

The most common type of malignant neoplasms in head and neck including tongue is squamous cell carcinomas (SCC). The two major causes of SCC are (1) tobacco, alcohol, and (2) human papillomavirus [1]. Adenoid cystic carcinoma (AdCC) is an infrequent malignant neoplasm and accounts for 1% of all head and neck malignancies and 10% of all salivary gland malignancies [2,3]. AdCC can occur in both major and minor salivary glands. The most common intraoral site for AdCC is the hard palate, followed by the base of the tongue. The presentation rate of AdCC in the base of the tongue is 8.8% [4–6]. AdCC in mobile tongue is extremely rare, with a reported incidence of only approximately 3% [7–9]. The optimal treatment for patients with AdCC is surgery and adjuvant radiation therapy, with a 5-year cause-specific overall survival rates of 74% [10,11]. Here we report a collision tumor of SCC and AdCC in mobile tongue, which has never been described before.

Case Report

An 88-year-old female patient with past medical history of dementia and hypertension presented with an ulcerative white lesion on the left side of lateral tongue. She had pain with swallowing. She was a former smoker (quit in her 20s). Several her family members had a history of throat cancer. A computed tomography (CT) scan of the neck demonstrated a 2.0 cm mass-like enhancement in the left lateral oral tongue, with an approximate 0.6 cm radiologic depth of invasion, suspicious for a primary oral tongue malignancy (Figure 1A). No cervical lymphadenopathy was identified. Laryngoscopy was performed and intraoperative frozen section suggested squamous cell carcinoma. The patient subsequently underwent partial glossectomy.

Weekly case conference

Figure 1. Imaging and histologic features of collision tumor. (A) Computed tomography imaging showing a 2.0 cm mass like enhancement (arrows) in the left lateral oral tongue. (B) Low magnification (hematoxylin-eosin stain, x20) showing collision tumor consisting of an adenoid cystic carcinoma (left) and conventional keratinizing squamous cell carcinoma (right). (C) High magnification (×100) showing adenoid cystic carcinoma. (D) High magnification (× 100) showing squamous cell carcinoma.

Macroscopically, a red-brown to gray-white ulcerated lesion was identified in the lateral tongue. Microscopic examination demonstrates a moderately differentiated keratinizing squamous cell carcinoma with a depth of invasion of 8 mm. However, adjacent to this classical squamous cell carcinoma, a morphologically distinct subepithelial tumor (0.5 cm in greatest dimension) was identified consisting of basaloid cells with tubular and cribriform growth patterns, morphologically consistent with AdCC. No mitosis or necrosis was identified in this small tumor (Figure 1 B-D).

Immunohistochemically, the tumor cells were strongly positive for c-KIT and SOX10. The ductal epithelial cells were positive for CK7; and the abluminal cells were positive for p63 and SMA (Figure 2). Ki67 proliferation index was approximately 15%. The immunoprofile confirms a diagnosis of AdCC. Thus, this whole lesion was classified as a collision tumor of SCC and AdCC.

Weekly case conference

Figure 2. Immunohistochemical stains performed on squamous cell carcinoma (upper panel, A-D) and adenoid cystic carcinoma (lower panel, E-H) (A&E: cytokeratin 7, B&F: p63, C&G: c-KIT, D&H: SOX10; magnifications ×200).

Discussion

SCC accounts for > 90% of all oral cavity malignancies. Among them, tongue (lateral and ventral) accounts for > 50% of cases. SCC is most commonly seen in elderly patients, and is associated with tobacco and alcohol use. AdCC of the salivary gland is a malignant epithelial tumor with epithelial and myoepithelial cells arranged in tubular, cribriform, and solid forms. It is seen in elderly patients with slight female predominance. AdCC arising from minor salivary glands of mobile tongue is extremely rare, with only few cases reported in the literature. Here we report the first case of collision tumor consisting of distinct components of conventional keratinizing SCC and AdCC, which were close to each other but clearly separated in the mobile tongue. Since AdCC is a small focus, it can easily be missed if the specimen was not entirely examined. Indeed, during frozen section, only the area of SCC but not AdCC was sampled.

AdCC is a rare neoplasm and not difficult to diagnosis in most cases. However, it can pose great challenge when it presents as part of a collision tumor like our case. AdCC typically has an infiltrative growth pattern that can destroy salivary gland tissue and invade into fat, skeletal muscle and soft tissue. The tumor is usually ill defined, unencapsulated with a firm, white-gray cut surface. Histologically, AdCC consists of small to medium basaloid tumor cells with scant eosinophilic to clear cytoplasm and basophilic angulated nuclei, with cribriform, solid, trabecular or tubular growth patterns. Mitotic features or necrosis are rarely seen. Immunohistochemical stains are helpful, showing tumor cells to be strongly positive for c-KIT while the ductal epithelial cells to be positive for cytokeratins. The basaloid abluminal cells are positive for myoepithelial cell markers such as p63, SMA and calponin [12]. Molecular or cytogenetics can be helpful, as 40–80% of AdCC is characterized by t(6;9)(q22–23;p23–24) translocations resulting in MYB-NFIB gene fusion. We have tested MYB fusion by FISH in our case and it is negative. MYB-NFIB gene fusion indicates poor prognosis [13].

The differential diagnosis of AdCC, particularly in this case, includes mainly other malignant salivary gland neoplasms with basaloid cells and cribriform growth patterns, such as polymorphous adenocarcinoma, basal cell adenocarcinoma, or basaloid SCC. Polymorphous adenocarcinoma is an uncommon malignant epithelial neoplasm consisting of uniformly bland, round to polygonal tumor cells with infiltrative growth. It can have tubular or cribriform patterns. The tumor has a unique p63+/p40- immunophenotype that helps distinguish it from AdCC [14]. Basal cell adenocarcinoma is a malignant basaloid salivary gland neoplasm showing epithelial and myoepithelial differentiation with invasion and sometime metastasis. It most commonly involves the parotid gland but is rarely seen in tongue. Basal cell adenocarcinoma shows well-developed peripheral palisading and consists of two cell populations: peripheral small dark basaloid cells and central large polygonal cells [15]. Basaloid SCC is a high-grade variant SCC composed of infiltrative basaloid cells and variable squamous component. Presence of squamous differentiation such as keratinization, squamous dysplasia, SCC in situ, or invasive SCC should raise suspicion against diagnosis of AdCC even in presence of cribriform growth [16].

In summary, we present the first case of collision tumor consisting of a conventional keratinizing SCC and AdCC. A diagnosis of this collision tumor can only be reached by complete histological examination of the lesion after surgical resection. Surgery is the choice of the treatment. Both tumor types need to be considered for therapeutic strategy and long-term follow-up is mandatory.

References

  1. Rettig EM, D’Souza G: : (2015) Epidemiology of head and neck cancer. Surg Oncol Clin N Am. 24: 379–396 [Crossref]
  2. Spiro RH, Huvos AG, Strong EW. (1974) Adenoid cystic carcinoma of salivary origin. A clinicopathologic study of 242 cases. Am J Surg. 128: 512–520 [Crossref]
  3. P.J. Bradley, (2004) Adenoid cystic carcinoma of the head and neck: a review Curr Opin Otolaryngol Head Neck Surg. 12: 127–132 [Crossref]
  4. Luna-Ortiz K, Carmona-Luna T, (2009) Cano-Valdez AM, Mosqueda-Taylor A, Herrera-Gómez A, Villavicencio-Valencia VV. Adenoid cystic carcinoma of the tongue clinicopathologic study and survival analysis. Head Neck Oncol. 1: 15 [Crossref]
  5. Soares EC, Carreiro Filho FP, Costa FW, Vieira AC, Alves AP. (2008) Adenoid cystic carcinoma of the tongue: Case report and literature review. Med Oral Patol Oral Cir Bucal. 13: E475–478
  6. Ustündag E, Iseri M, Aydin O, Dal H, Almaç A, Paksoy N. (2000) Adenoid cystic carcinoma of the tongue. J Laryngol Otol. 114: 477–480
  7. Baskaran P, Mithra R, Sathyakumar M, Misra S. (2012) Adenoid cystic carcinoma of the mobile tongue: A rare case. Dent Res J (Isfahan). 9 Suppl 1: S115–118 [Crossref]
  8. Kumar S, Agarwal P, Nimmi V. Adenoid cystic carcinoma: A rare late presentation of the mobile tongue. J Oral Biol Craniofac Res. 2016; 6: 164–167 [Crossref]
  9. Patnayak R, Jena A, Inamdar MB, Reddy GV, Appasani S, Bodagala V. (2016) Adenoid cystic carcinoma of mobile tongue. Int J Oral Health Sci. 6: 92–95
  10. Silverman DA, Carlson TP, Khuntia D, Bergstrom RT, Saxton J, Esclamado RM. (2004) Role for postoperative radiation therapy in adenoid cystic carcinoma of the head and neck. Laryngoscope. 114: 1194–1199 [Crossref]
  11. Mendenhall WM, Morris CG, Amdur RJ, Werning JW, Hinerman RW, Villaret DB. (2004) Radiotherapy alone or combined with surgery for adenoid cystic carcinoma of the head and neck. Head Neck. 26: 154–162 [Crossref]
  12. Jaso J, Malhotra R. (2011) Adenoid cystic carcinoma. Arch Pathol Lab Med. 135: 511–515 [Crossref]
  13. Persson M, Andrén Y, Mark J, Horlings HM, Persson F, Stenman G. (2009) Recurrent fusion of MYB and NFIB transcription factor genes in carcinomas of the breast and head and neck. Proc Natl Acad Sci U S A. 106: 18740–18744 [Crossref]
  14. Rooper L, Sharma R, Bishop JA. (2015) Polymorphous low grade adenocarcinoma has a consistent p63+/p40- immunophenotype that helps distinguish it from adenoid cystic carcinoma and cellular pleomorphic adenoma. Head Neck Pathol. 9: 79–84 [Crossref]
  15. Cuthbertson DW, Raol N, Hicks J, Green L, Parke R. (2015) Minor salivary gland basal cell adenocarcinoma: a systematic review and report of a new case. JAMA Otolaryngol Head Neck Surg. 141: 276–283
  16. Barnes L1, Ferlito A, Altavilla G, MacMillan C, Rinaldo A, Doglioni C. (1996) Basaloid squamous cell carcinoma of the head and neck: clinicopathological features and differential diagnosis. Ann Otol Rhinol Laryngol. 105: 75–82 [Crossref]

The metabolic rewiring observed in cancer renders tumor cells dependent of ketone bodies and vulnerable to SCOT inhibition

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DOI: 10.31038/EDMJ.2020412

Abstract

The finding that autoantibodies against glutamic acid decarboxylase that synthesizes GABA, provoke Diabetes type I, draws attention on a GABAergic regulation of the endocrine pancreas suppressing catabolic glucagon release if anabolic insulin is liberated; a GABA deficiency would then impair this exclusion mechanism, allowing a release of both hormones. Moreover, the GABA deficiency alters a mechanism terminating insulin release; an insulin leakage renders differentiated cells gradually resistant to insulin, while responding to glucagon. Mitotic cells with new insulin receptors, respond to both hormones, displaying a hybrid metabolic pattern typically found in tumor cells. They cannot get their mitochondrial acetyl CoA from glycolysis, since pyruvate kinase and pyruvate dehydrogenase are OFF, following the glucagon signal. Nor can they form acetyl CoA by the beta-oxidation of fatty acids, since the insulin signal they receive elicits the synthesis of fatty acids, which automatically closes their beta-oxidation. Indeed, malonyl CoA produced along the lipogenic pathway inhibits the mitochondrial carnityl-transporter of fatty acids. Hence, with both the glycolytic and fatty acid sources of mitochondrial acetyl CoA closed, tumor cells can only get their vital mitochondrial acetyl CoA supply from the ketolysis of ketone bodies.

Differentiated tissues resistant to insulin, but responding to glucagon, adequately provide these ketone bodies. The enzyme, Succinyl-CoA: 3-oxoacid-CoA transferase (SCOT) is specific to ketolysis producing acetyl CoA. Its inhibition deprives tumor cell mitochondria of acetyl CoA, which should hold back tumor development. Inhibiting also the cytosolic acetyl CoA synthetase that tumor cells use for feeding their lipid synthesis should block the tumor.

Keywords

Endocrine pancreas, tumor cell metabolism, Ketone bodies dependency, SCOT inhibition, Acetyl CoA synthetase inhibition

Introduction

Insulin dependent Diabetes (type 1) may result from an attack of pancreatic beta cells, by autoantibodies against, the enzyme synthetizing GABA [1]. We do know that pancreatic beta cell co-release insulin and GABA, insulin release corrects hyperglycemia, while GABA will inhibit, via GABA A ionotropic receptors, neighboring delta and alpha cells, respectively releasing somatostatin and glucagon. Hence, the release of anabolic insulin is associated to a mechanism switching off, via GABA, catabolic glucagon release and somatostatin release [2, 3]. Moreover, GABA acts on beta cell auto-receptors (metabotropic GABA B) for putting an end to insulin release [4]. A GABA deficiency will then fail to completely, turn–off insulin release, the resulting leakage of insulin will desensitize in the long-run insulin receptors in differentiated cells (an effect reminding Type II diabetes or metabolic syndrome) [5]. The deficiency of GABA release also affects the mutual exclusion process of catabolism when anabolism takes place, sending a dual message to cells. Differentiated tissues resistant to insulin will take the catabolic part of this message and develop a neoglucogenic and ketogenic metabolism. Whereas cells that are not resistant to insulin, will receive both insulin and glucagon messages; these are new mitotic stem cells, with new insulin receptors, not yet affected by the chronic desensitization provoked by insulin leakage. These cells will rewire their metabolism as one observes for tumor cells [6-10].

Metabolic rewiring in cancer: A consequence of mixed pancreatic signals

Tumor cells are avid for glucose, and insulin elicits the incorporation of glucose transporters in their membrane. Indeed, following the binding of insulin to its tyrosine kinase receptor and the activation of MAP and PI3 kinases a downstream effect stimulates a phospholipase forming inositol 3, 4, 5 Phosphate (IP3) and diacyl glycerol (DAG). Then, an IP3-mediated calcium release from the reticulum in the cytosol triggers the exocytotic incorporation of glucose transporters in the cell membrane. In parallel, glycolysis increases because the decline of cAMP, elicited by a calcium-activated phosphodiesterase, cancels the inhibitory action of cAMP over fructose 2, 6 bis P synthesis, which increases this activator of glycolysis; incidentally, drugs like rolipram that inhibits the phosphodiesterase, would keep up cAMP and limit the glycolytic flux. In spite of the avid glucose influx, the phosphorylation of pyruvate kinase (PK) and pyruvate dehydrogenase (PDH), which inhibits these enzymes, closes the last steps of this increased glycolysis of tumor cells. In fact, tumor cells express the M2 form of PK that gives inactive dimers rather than active tetramers, forming a “bottleneck” at the end of the glycolytic pathway [11, 12]; which switches off the glycolytic production of acetyl CoA by PDH. The PK bottleneck increases the influx of substrates into the pentose pathway, while phosphoenolpyruvate (PEP) accumulated above the PK bottleneck, will rather convert to oxaloacetate (OAA) via PEP carboxykinase (PEPCK). What maintains this phosphorylation of PK and PDH? Presumably, the inhibitor CPI 17 of their phosphatase is synthetized via a stimulation of protein kinase C (PKC) by DAG [13]. We indeed know that PKC stimulates the production of this inhibitor, which cancels the calcium-dependent activation of the phosphatase PP1 by calcineurin that normally inactivates another inhibitor I1, of PP1 phosphatase. Then what keeps DAG elevated? We know that growth hormone stimulates adipose triglyceride lipase (ATGL), which produces an excess of DAG. The stimulation of growth hormone is itself a consequence of the GABA deficiency, because it is not limited to the pancreas. Low GABA increases epinephrine release from the adrenals, which inhibits somatostatin release. Consequently, growth hormone and IGF increase. In this respect, ATGL inhibitors would deserve a try [14]. Inhibition of growth hormone, DAG and PKC should also be interesting (remember that DAG acts on PKC similarly to phorbol ester carcinogens).

In sum, the glycolytic source of acetyl CoA at the entry of the Krebs cycle is well closed. On the other hand, the insulin anabolic action boosts synthetic processes and fatty acid synthesis, needed for making new membranes for mitotic cells. In this pathway malonyl CoA, the product of acetyl CoA carboxylase (ACC) at the beginning of the pathway, inhibits the transport and degradation of fatty acids in mitochondria, closing the beta-oxidation pathway, and the fatty acid source of acetyl CoA. Indeed, when fatty acid synthesis operates, the degradation of fatty acids automatically stops. Hence, if the two sources of mitochondrial acetyl CoA (glycolytic or fatty acid) are closed, mitotic stem cells will have to get their acetyl CoA from the ketolysis of ketone bodies, coming from the liver or other tissues selectively responding to catabolic hormones. Thus, with acetyl CoA that comes from ketolysis and (OAA) coming from phophoenol pyruvate (PEP), via PEP carboxykinase (PEPCK) and other sources, the citrate condensation takes place, starting the Krebs cycle [15, 16].

Ketogenesis and tumor cell ketolysis

We represent in Figure 1, a hepatocyte (left), responding to glucagon, it produces glucose and ketone bodies; the beta-oxidation of fatty acids is active, they enter in the mitochondria via the fatty acid acyl carnitine transporter, and will produce intra mitochondrial acetyl CoA. Then, four enzymes indicated in the figure 1, support ketogenesis, they lead to beta hydroxybutyrate, after the reduction of acetoacetate; the latter also degrades into acetone and CO2 (not represented). In catabolism, ketogenic amino acids such as leucine and a few others, also feed the ketogenic pathway with acetyl CoA and acetoacetyl CoA, leading to acetoacetate and beta hydroxybutyrate. The released beta hydroxy butyrate enters the tumor cell (right), through a transporter. It then reaches the mitochondria, where three enzymes indicated in the figure 1, will support ketolysis, resulting in acetyl CoA; the enzyme succinyl CoA 3- oxoacid- CoA transferase (SCOT) is the specific step. This ketolytic source of acetyl CoA is vital for tumor cells, since the other sources of mitochondrial acetyl CoA: the glycolytic (via PK and PDH), or the beta-oxidation of fatty acids, are both not working in tumor cells as described above. Thus, only ketone bodies provide acetyl CoA (via SCOT) to the citrate condensation reaction that starts the Krebs cycle. The citrate condensation is particularly active; but the citrate will quit the mitochondria and enter in the lipogenic pathway in the cytosol, forming fatty acids and lipids that are essential to build new membranes for mitotic cells. Thus blocking SCOT, the citrate efflux; and ATP citrate lyase, should hinder tumor development.

Tumor cells can still save their situation because they have in the cytosol an enzyme, acetyl CoA synthetase directly converting incorporated acetate into acetyl CoA [17]. Incidentally, we know that cholinergic neuromuscular synapses use acetate in preference to pyruvate for making acetyl CoA via this same enzyme, and then the acetyl moiety of acetylcholine, whereas brain cholinergic synapses use pyruvate rather than acetate for synthesizing the acetyl moiety of acetylcholine [18]. In tumor cells, acetyl CoA synthetase converts incorporated acetate into acetyl CoA, which enters in the fatty acids synthesis and the lipogenic pathways; in parallel, acetyl CoA forms acetoacetyl CoA in the cytosol via a cytosolic thiolase, and feeds the cholesterol-synthesizing pathway. In addition, we also find an acetoacetyl CoA synthetase activity in tumor cells. The acetyl and acetoacetyl CoA synthetases are enzymes forming adenylate intermediates before acetylation or acylation; inhibitors for these adenylating enzymes are available.

EDMJ Maurice

Figure 1.

Figure 1: Ketone bodies are vital for tumor cells. On the right, a tumor cell has a single ketolytic supply of mitochondrial acetyl CoA, of the three enzymes that form the pathway, Succinyl-CoA: 3-oxoacid-CoA transferase (SCOT) is specific for ketolysis. Note that the glycolytic and fatty acid sources of acetyl CoA are both interrupted; on the glycolytic side, pyruvate kinase and pyruvate dehydrogenase are OFF in tumors; and on the fatty acid side, their degradation will stop since fatty acid synthesis is active; indeed, the malonyl CoA intermediate, closes the carnityl transporter of fatty acids and beta oxidation. The citrate efflux in the cytosol feeds ATP citrate lyase, giving back acetyl CoA and oxaloacetate. Acetyl CoA follows the synthesis pathway of fatty acids, via acetyl CoA carboxylase (ACC) and fatty acid synthetase (FAS). The ACC forms the malonate inhibitor of fatty acid degradation. Tumor cells possess an acetyl CoA synthetase that converts the exogenous acetate influx into acetyl CoA, supporting the lipogenic pathway and the synthesis of acetoacety CoA via a cytosolic thiolase. Tumor cells also have an acetoacetyl CoA synthetase feeding the cholesterol synthesis pathway. On the left, a differentiated cell, a hepatocyte, resistant to insulin but responding to catabolic glucagon; produces glucose and ketone bodies. Fatty acids enter in the mitochondria via their carnityl transporter, and give by beta-oxidation acetyl CoA. The latter follows the ketogenic pathway, which consists of four enzymes, indicated in the figure. Ketogenesis forms acetoacetate and beta hydroxybutyrate. After release, beta hydroxybutyrate enters the tumor cell via a transporter; then in the tumor cell mitochondria, to give acetyl CoA by ketolysis; SCOT is the specific step, supporting this vital supply of acetyl CoA to the tumor cell, is its vulnerable point.

Color-code, in hepatocyte Beta-oxidation (blue arrow) ketogenesis (red arrows). In tumor cell: Interrupted Beta-oxidation and glycolytic supplies of acetyl CoA (dotted blue and black arrows) interrupted by small double arrows. Red arrows show ketolytic steps, (same enzymes as ketogenesis) except SCOT. Acetyl CoA starts the Krebs cycle, citrate release, ATP citrate lyase (green arrows). Salvage pathway: acetyl CoA synthetase (orange arrow), Lipogenic route (yellow arrows) and Cholesterol synthesis indicated by mauve arrows.

The ketogenic diet might not be a good idea

Initially, the ketogenic diet aimed to decrease the supply of glucose to tumors by replacing the glucose by ketone bodies, our other nutrient, provided by a high fat diet. However, in spite of several encouraging clinical reports, it seems that the ketogenic diet may not be a good idea, since ketone bodies are the only way for tumor cells to get their mitochondrial acetyl CoA. Several other works indicate that the utilization of ketone bodies drives tumor growth and metastasis; [19, 20] this agrees with the present work indicating that tumor cell metabolism vitally depends of ketolysis, for their mitochondrial acetyl CoA supply. It is thus “a priori” not indicated to follow a ketogenic diet. It was then necessary to find out the clinical circumstances that introduced this diet. The recent publication of Klement [21] on the forgotten contribution of Wilhelm Brünings, is in this respect particularly interesting. Following the discoveries of Warburg on tumor metabolism [22, 23] (high glucose fermentation to lactate, in presence of oxygen). Brünings proposed to decrease the glucose supply to tumors, using a low carbohydrate diet and insulin induced hypoglycemia. However, it was necessary to feed patients with a diet replacing the carbohydrates, by lipids and proteins (the ketogenic diet was developed). The preliminary observations were encouraging; however, after several weeks there was a rebound of the tumors and much disappointment (See the detailed description by Klement [21].

What can we say on these trials? Evidently, in Diabetes type I the loss of beta cells and decrease of insulin release leads to hyperglycemia, with a loss of control over alpha cells that release glucagon, which elicits a ketogenic metabolism classically found in Diabetes. On the contrary, when one injects insulin to an individual, there is a drop of blood glucose, since tissues take it up. Here, insulin counteracts the release of catabolic glucagon that normally elicits the production of glucose and ketone bodies. Hence, in Burning’s trial, the initial effects of insulin-induced hypoglycemia must have been associated to a parallel decrease of ketogenesis, since insulin inhibits the alpha cell, via a mechanism that is not in this case GABA-mediated (we describe it later). The decrease of ketone bodies provoked by the insulin-mediated blockade of glucagon release in this initial phase of the trial coincides with the decrease of tumor sizes. Indeed, without ketone bodies, tumor cells could not make their mitochondrial acetyl CoA. However, with the gradual onset of the ketogenic diet, the supply of ketone bodies to the tumor starts again, and a rebound of the tumor sizes took place; the results of trial were disappointing.

The direct effect of insulin, over pancreatic cells has been recently unraveled [24]. Apparently, insulin acts on delta cells insulin receptors, eliciting a glucose influx through glucose transporters and through the activation of an electrogenic co- transporter of glucose and sodium (SGLT2), the sodium-glucose luminal transporter 2. The resultant increase of glycolysis forms ATP, which closes K ATP channels. The overall membrane depolarization then opens calcium channels and triggers an influx of calcium, which induces via ryanodine receptors, a further mobilization of calcium stores from the reticulum, activating the release of somatostatin from delta cells. The paracrine effect of somatostatin over neighboring cells is to inhibit both glucagon release from alpha cells and insulin release from beta cells. Thus, in relation to Brüning’s trial, injected insulin, which elicits hypoglycemia, will directly stimulate delta cells releasing somatostatin, which in turn inhibits the release of glucagon from alpha cells, the counter regulation by glucagon is OFF; neither glucose production nor ketogenesis take place after the insulin injection. Hence, the ketone bodies will decrease, depriving tumor cells of their vital acetyl CoA supply, in this initial phase of the trial tumor sizes decrease. Later, the ketogenic diet gradually provides to tumors ketone bodies, and ketolysis feeds their mitochondria with a vital acetyl CoA supply, while the rebound of tumors took place.

However, at an epigenetic level, beta hydroxybutyrate inhibits histone deacetylase (HDAC); acetylated histones increase, which may favor the expression of genes that are silent in cancer, such as P53, which could be favorable if it occurs. On the other hand, we know that the butyrate inhibition of HDAC induces the expression of embryonic genes; it is the case for fetal hemoglobin or utrophine and others. Thus, the expression embryonic M2 pyruvate kinase in tumor cells, instead of the M1 regulated adult form, might be a consequence of an increased supply of ketone bodies and HDAC inhibition, and this is not favorable, since the M2 form of PK, causes the glycolytic bottle neck in tumor cells.

SCOT inhibition: A possible cancer treatment

The therapeutic elements we propose, in relation to this metabolic presentation, have still to go through tests on animal models, before adding them to actual therapies that have a long experimental background. Moreover, even if the compounds proposed come from published observations, they need an evaluation for the toxicity of mixtures, which could be different from the toxicity of each compound, prescribed for other indications.

In Figure 2, the numbers indicate a selection of enzymes to target. There are six points of attack that we have chosen. The first target number 1 in figure 2, is the ketolytic enzyme SCOT. The list of inhibitors found in the Brenda chemical database, contains many compounds that are difficult to use or probably toxic, such as dinitrophenyl acetate, or 2, 2 difluoro succinate [25] others could indeed be tested: desulfo CoA, desulfopanteteine, acetylimidazole, 3 sulfopropanoate, N- acetylcysteamine, citrate, iodine and more. We then found in the work of Picard and Jenks [26] on the active center of SCOT a particularly interesting compound: acetohydroxamic acid, which inhibits the enzyme-substrate complex. Acetohydroxamic acid is available as tablets under the name of lithostat, against kidney stones and bladder infections, caused by bacteria raising the ammonia level in urine. Salicylhydroxamic acid is also an interesting compound to test. Moreover, we found that a class of histone deacetylase inhibitors is hydroxamic acid derivatives, such as suberoylanilide hydroxamic acid (SAHA), or trichostatine, or vorinostat and others, they do display anticancer properties [27]. However, we find no mention for a possible inhibition of SCOT in this observation, but this would indeed explain the observed anticancer properties. The compounds we preferably select for inhibiting SCOT are acetohydroxamic acid, and derivatives such as SAHA, or vorinostat. The next target, number 2 in figure 2 aims to decrease the efflux of citrate from the mitochondria to the cytosol, where citrate hydrolysis by ATP citrate lyase gives back acetyl CoA and OAA. In previous works, lipoic acid (the co-factor of PDH) associated to the ATP citrate lyase inhibitor hydroxycitrate, gave good results on animal tumors [28]. We think that lipoic acid has in fact slowed down the citrate condensation reaction; by probably reducing NAD into NADH, which inhibits citrate synthetase. Presently, we suggest keeping hydroxycitrate; there are also other ATP citrate lyase inhibitors such as bempedoic acid [29]. We would again associate hydroxycitrate and lipoic acid as previously, if lipoic acid does not cause a reactivation of SCOT after its inhibition by acetohydroxamic acid; if this was the case, we would omit lipoic acid. The acetyl CoA produced by ATP citrate lyase in the cytosol follows the lipogenic pathway, while OAA pushes the transamination chain leading in fine to pyruvate and lactate. OAA converts to malate, shuttles in mitochondria and gives aspartate that enters in several pathways that are not the subject of the present work. At the end of the lipogenic pathway we find fatty acid synthetase (FAS), this target is our number 3 in the figure 2, inhibitors are: cerulenin, C75 or orlistat, we retain orlistat for example, this would maintain the intermediate concentration of malonyl CoA that closes the beta oxidation of fatty acid[30].

It is necessary to decrease the cytosolic synthesis of acetyl CoA by inhibiting acetyl CoA synthetase (ACS), this enzyme uses as substrate acetate taken-up by tumor cells; this target is number 4 in figure 2. Acetyl CoA synthetase belongs to a class of enzymes forming adenylate intermediates, similarly to acetoacetyl CoA synthetase (AACS), which is target number 6 in figure 2, along the cholesterol synthetizing pathway. Inhibitors of adenylate forming enzymes are sulfonyladenosines or celecoxib derivatives (AR12, AR14), or adenosine 5’- ethyl phosphate, we also find a quinoxaline derivative [31, 32, 33, 14]. Other simpler compounds, such allicine from garlic, inhibit acetyl CoA synthetase [34]. This is also the case of an active substance from cow milk, which could be orotic acid [35]. Orotic acid and allicin are available as tablets. In between acetyl CoA synthetase (target 4), and acetoacetyl CoA synthetase (target 6); a cytosolic thiolase operates, this target is number 5 in figure 2; Inhibitors of thiolase such as trimetazidine (vastarel) or 4- pentenoic acid are available but difficult to handle [36].

A compound such as dichloroacetate, which activates PDH by inhibiting PDH kinase, displays a parallel blockade of ketolysis [37]. In the context of the present work, this is particularly interesting, since dichloroacetate has known anti-tumor effects. In addition, dichloroacetate presumably inhibits the acetyl CoA synthetase, which feeds acetate in the lipogenic pathway. Finally, along the cholesterol synthesis pathway, statins classically inhibit 3-hydrox 3- methyl glutaryl CoA synthetase and cholesterol synthesis, this target is number 7 in figure 2. A first choice for blocking the tumor could be acetohydroxamic acid or a derivative, plus hydroxycitrate, allicine, or orotic acid and lipoic acid (if it does not reactivate SCOT). Dichloroacetate orlistat and the other enzyme inhibitors that we mention because they validate the mechanism discussed, have to go through toxicity tests before. We only recommend compounds that one prescribes for other medical indications with no side effects, after testing the mixture on animal models.

EDMJ Maurice - Figure2

Figure 2.

Figure 2: Enzymatic targets to stop the progression of tumors. Glycolytic and fatty acid supplies of mitochondrial acetyl CoA are not operational in tumor cells: (Pyruvate dehydrogenase (PDH) is OFF and malonyl CoA inhibits the fatty acid carnityl transporter (double black interruptions). The only supply of acetyl CoA comes from ketolysis via succinyl-CoA: 3 oxoacid- CoA transferase (SCOT) target number 1, its inhibition by acetohydroxamic acid or derivatives is represented by the red double arrow, as for next targets. The citrate efflux and ATP citrate lyase is target 2, previously tested compounds are lipoic acid, and hydroxycitrate. At the end of the fatty acid synthesis pathway, target 3 is fatty acid synthetase (FAS), orlistat is a possible inhibitor but requires toxicity tests. Target 4 is acetyl CoA synthetase (ACS), inhibitors are allicine or orotic acid, others that we mention in the text such as sulfonyladenosines inhibit acetoacetylCoA synthetase (AACS) (target 6) they also require toxicity tests. In between, target 5 is a cytosolic thiolase, inhibitors are trimetazidine and 4 -pentenoic- acid they are difficult to handle. The last target is the enzyme 3 hydroxy 3-methyl glutaryl CoA synthetase (target 7) statins inhibit this enzyme and lower cholesterol but have side effects. In our opinion targets 1, 2 and 4 are those we would handle first, with acetohydroxamic, hydroxycitrate and allicine or orotic acid, we would add lipoic acid if it does not reactivate SCOT.

Discussion

By inhibiting SCOT and the ketolytic source of acetyl CoA, one suppresses the only supply of acetyl CoA for tumor cell mitochondria; indeed, the other sources glycolytic and fatty acid are not operating, since PK and PDH are OFF, forming the glycolytic bottle neck, while the fatty acids degradation is OFF, when fatty acid synthesis is ON. Hence, the blockade of SCOT deprives tumor cells of their vital acetyl CoA supply; they should then regress. In the cytosol of tumor cells, a supply of acetate can still feed acetyl CoA synthetase and the lipogenic pathway, inhibiting this entry as well, would make it difficult for tumor cells to synthesize their membranes, they should die or have to normalize their metabolism.

In earlier works, we proposed to try to normalize cancer metabolism, by controlling the starter mechanism that rewires metabolic pathways in cancer: the pancreatic GABA trigger, the elevated cAMP, the growth hormone – ATGL- DAG- PKC axis. The latter leads to the inhibition protein phosphatases and activation of kinases, and perturbs metabolic switches controlling cancer metabolism in differentiated cells and tumor cells (16). Normalizing cancer metabolism requires an elevated number of compounds. We found some active minimal combinations but much work remains unfinished, in spite of interesting possibilities to test. The present proposal is different, since it takes advantage of the weak point of tumor cell metabolism; that vitally depends of SCOT and acetyl CoA synthetase. Their inhibition should hold back the development of tumors, giving a new possibility to add to the treatment of cancer.

Footnotes

Conflict of interest statement: The authors have no conflict of interest related to the manuscript

Manuscript source: Invited manuscript.

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Healthy Boundaries Relationship Model

1 Reply

DOI: 10.31038/PSYJ.2020221

Abstract

Healthy Boundaries Relationship Model is a comprehensive discussion about the dynamics of maintaining respectful boundaries to protect your marriage. Emotional affairs and manipulating people who intrude on married couples or committed couples are problematic when proper boundaries are not maintained. Emotional affairs are not widely acknowledged compared to sexual affairs. Hidden in the guise of ‘friends only’ status can make them difficult to identify, yet, can easily ruin the best of any marriage or committed relationship. There are many influences and human flaws that can threaten your committed relationship through every day experiences. This article addresses couples with insight into the importance of exercising healthy boundaries to protect their relationship, along with identifying ploys from manipulative people, what an emotional affair looks like, and guidelines to help couples protect and/or restore their marriage.

Keywords

marriage, spouse, boundaries, manipulation, emotional affairs, third-party

Healthy Boundaries Relationship Model

Healthy Boundaries Relationship Model is a relationship model that outlines boundaries for a married couple or any couple in a committed loving relationship. As there are no guidelines that rule every couple, there are, however, compelling reasons for every couple to decide where boundaries lie for them in reference to opposite sex-friends, or any person posing as a romantic threat [1]. This dialogue theorizes the topic of affairs and healthy boundaries while simultaneously addressing couples in a committed relationship. It will maintain the terms ‘third- party friendship, third-party relationship, third-party person or intruder,’ as any type of third- party relationship that is outside of, or separate, or secret from the committed relationship which poses a romantic threat. For the sake of simplifying vocabulary, the terms ‘marriage and spouse’ refers to any type of committed loving relationship between two adult people.

What is a Boundary?

Boundaries come in all shapes and sizes. Psychological boundaries are invisible mental guidelines that determine what we do and do not do, and, what we will and will not accept in our lives. They are created when we realize where our limits are. Boundaries reflect our values, thoughts, and feelings that are important to us, and are held together by our actions. We create boundaries to protect the things we love [2].

We love our home; we lock the doors for safety to protect our possessions inside. We love ourselves; we create boundaries to protect ourselves from harm and hurt from others. We love our families; we create boundaries to protect them and the relationships we share with them. We love our partner. We love the love we feel inside our hearts from them. We love our relationship with them, and the sacred space that fills the intimacy in our bond with them. We create boundaries for our marriage to protect our partner and our relationship. Boundaries regarding third-party friendships are guidelines that the couple decides upon to protect their marriage.

When we have healthy boundaries in our relationship, we take into consideration how our partner feels. We show appreciation and respect for the differences in our opinions, but most especially show respect for each other’s feelings. In relationships with unhealthy boundaries we may be unknowledgeable, or assume our partner feels the same way we do in any various situations where we may inadvertently overstep proper boundaries causing misunderstandings, and perhaps great pain [3]. The Healthy Boundaries Relationship Model holds each other’s feelings in check with a responsibility to support the integrity of the relationship, support trust, and respect for each other. Each person is accountable for their behavior. To live by, ‘putting your relationship first before your need to be right or in competition with outside demands and influences’ [4] places boundaries at the top of the list as one tool to ensure a healthy relationship with your loved one, your spouse.

Why Have Boundaries?

The simple truth about taking measures to protect your marriage is based on the fact that we are all sentient human beings; meaning, we have the capacity for awareness, feelings, responding, and reacting to others [5]. This is not to suggest you are a promiscuous person by nature ready to fall into bed with anyone who comes along, or that you are a deliberate betrayer. But you are a human being with the capacity to feel, interact, respond with feelings, and have relationships. Being a sentient being is the foundation of human nature, and no one is immune to it. Avoiding situations that may provoke feelings of attraction, emotional or any type of unhealthy involvement, neediness, or desires for someone else that may threaten your marriage is living within the guidelines of healthy boundaries for you and your spouse. We protect the things that we love. Our ability to protect our marriage is related to the strength of the boundaries we maintain, emotional or physical [6]. Our boundaries are maintained by our actions [2].

Defining Boundaries: The first step in setting boundaries is through self-knowledge.

Learn what is important to you [3]. Boundaries set the tone for how much we allow others to influence us emotionally. Based on the thought that most people make decisions because of their emotions instead of logic, healthy boundaries deflect outside influences that may put our marriage at risk from unhealthy influences or a misunderstanding with your spouse.

A misunderstanding, for example, if you are spending large amounts of time with a third- party person, or interacting in ways that seem overly friendly, perhaps appearing flirtatious, your spouse may become very hurt and upset. You may have not thought anything about it, assuming it was harmless fun. By maintaining awareness of boundaries to place your marriage first, these types of situations can be avoided or managed appropriately. In other words, boundaries place responsibility upon you to conduct yourself appropriately with others, and how you allow others to interact with you.

Thirdly, boundaries define who you are as a couple. It provides the foundation of trust that each of you will conduct yourself properly with the outside world when you are not together. It is an announcement to the outside world that you are a couple, not a single person available to the wind of other people’s desires, influences, and interests.  Healthy boundaries puts your marriage first because it demonstrates respect for your spouse while reinforcing trust. It supports trust through the concept and exercise of healthy boundaries because healthy boundaries provide an umbrella of emotional safety. Do not underestimate the importance of boundaries in your marriage and in your life.

What are the Risks?

Statistics say that approximately 40% of all marriages will experience an affair [7]. There are many reasons why a person chooses to be unfaithful. The reason may be personal insecurities or character flaws which may not be reflective of the marriage at all, or of their partner [8]. Often, however, people fall into having an affair when they least expect from a seemingly harmless friendship. Feelings of neglect, conflict in your marriage, feeling an emotional void, frustrated, and angry may lead you to seek emotional comfort outside of the marriage. Stress and vulnerability may influence you to lower your guard without realizing it [7] or lose sight of your boundaries altogether. You are a sentient being. You have feelings and needs and wants just like anyone else. Naiveté and vulnerability can easily take control of you when you are not in control of yourself. Exercising healthy boundaries in your behavior is exercising self-control. No matter how stressful your marriage is, there is never a good reason for having an affair, as the aftermath is always heart-shattering. In every situation of unfaithfulness, however, having an affair is not a couple’s choice. It is always the choice of one member in the marriage who decided to step outside of the relationship [9].

Individual Boundaries

Some people may not be aware of the concept of boundaries. The risk of not having boundaries leaves a person wide open to following paths that they may have never intended to go. If you were raised in a home where boundaries were violated, never acknowledged or respected, you may not have an understanding of boundaries for yourself. Many people fear that enforcing boundaries, as in when you say ‘no’ is rude. Their need for approval takes priority over saying no. Thus, their fear of rejection outweighs their ability to set healthy boundaries [2].

Learning your own sense of boundaries as an individual ground’s you with personal strength to express who you are. Expressing your boundary is not an argument with anyone, it’s a statement about you, “This is who I am.” Personal boundaries are about respecting yourself, setting a stance for your individuality upholding standards that are right for you. It demonstrates you have control of your life [9]. It is not an argument. It is not a persuasive conversation with someone. It is an act of living your life authentically by upholding what you value. If you don’t uphold your boundaries for values that are important to you, more than likely no one else will either. Some people will try to manipulate you away from your values. But your boundaries will protect what you value, and prevent you from falling to the persuasion of others [2]. Healthy personal boundaries are just as important as relationship boundaries. Know your limits as an individual. Know what you will and will not tolerate, or participate in. Boundaries are guides for you to live authentically, and confidently with your true self. Although the concept of boundaries may seem rigid, it is not putting up walls around yourself from others. It is accepting and respecting yourself while respecting others. There is a gentle flexibility in exercising boundaries without building walls or losing the distinction of your individuality [6].

Third-Party Manipulators

While some people have no concept of boundaries, or simply do not have a defined set of boundaries, some people may know boundaries well enough to manipulate others. In fact, they may be inclined to manipulate your boundaries without your awareness. How so? In any multitude of ways: flattery, insincere emotional support, pretending to support your values when they themselves do not have values. They may share in a membership with you, clubs, or an organization. They may ask your advice when they already know the answer, asking favors of you [10] a friendly touch on the shoulder, and so forth are all examples of manipulative, coercing gestures.

There are many types of psychological manipulations that may seem like normal conversations and interactions. While it may seem normal and friendly, a third-party intruder may have maleficent intent to covertly intrude on your marriage with no concern about the effect it may have on you or your spouse. You are a sentient being. You have the capacity for feelings and responding like most normal people. A manipulative person knows this and uses it to their advantage. Understanding the manipulative mechanisms of third-party intruders is imperative for identifying them before you or your spouse are pulled in to the guise of their ploys. Knowing why people manipulate, and what manipulation looks like is valuable to prevent manipulation from occurring in the first place, can save from unpleasant situations, and perhaps lives.

For example, in 1978 the cult leader, Jim Jones psychologically manipulated over 900 people to commit suicide by drinking grape punch laced with cyanide. Before this suicidal measure of devotion, these vulnerable people were manipulated to turn on their families, and disconnected from them to follow his teachings and lifestyle. Once this was accomplished, he then manipulated his cult members into abusive acts, and to ultimately turn on each other if they did not follow the rules [11]. These people were extremely vulnerable and became victims of manipulation in the worst way.

Frailty of the Human Mind

There is a fundamental weakness in the human mind, a truth that applies to all. We are all at risk to the frailties of human nature, and subject to the persuasion of others [11]. Having vulnerabilities, and being vulnerable is part of the human experience. The Jim Jones story is an extreme example of manipulation. But manipulative tactics that influence us cannot be underscored in everyday life, including personal relationships. The psychodynamics of persuasion influences us in nearly every area of life every day [12]. Advertisement, music, art, literature, public speakers, corporate leaders for the organization we work for, conversations and interactions with friends, peers, family, and so forth all influence us throughout the day. A third-party person from our everyday life, who knows how to manipulate boundaries can influence any one of us without our awareness. We are sentient beings. We respond. We feel. We think the best of people by nature, without realizing others may not have the best of intentions for us.

What is Manipulation?

By definition, manipulation is the ability to influence another person by circumventing their sense of reason, with deliberate intent to induce a faulted thought or perception, a belief, a desire, or an emotion into someone [13]. The effect on the victim being manipulated results in a distortion in their normal decision-making process, which leads them to a thought, a feeling, a belief, a decision, or an action without knowledge of the manipulation being placed upon them. It is most generally viewed as an act that aims, “To achieve a desired goal using deception, coercion, and trickery, without regard for the interests or needs of those used in the process,” [14]. The style of manipulation can be covertly or aggressively. Covert measures are implemented in a manner that is secret, hidden, or not easily noticed. This form of manipulation is applied to win support from another individual, or group. This influence is focused on personal gain without concern of harm to others, achieved through acts of preying on another by using misleading messages, complaints, hidden intentions, and strategies. The personal gain for the third-party intruder is without empathy towards others affected by the manipulation [13] which means you or your spouse.

What is Their Motivation?

People with manipulative tendencies are often individuals with deep-rooted psychological insecurities. Their success in persuading others feeds their ego, leaving them with feelings of personal power. It is an ego-boosting method of building self-esteem that is, in reality, deeply missing. There are many types of personality disorders that classify maladaptive behaviors, manipulativeness, and apathy towards others.

To simplify, women, for example, who have affairs with married men, may find the experience thrilling from the perspective of the accomplishment to persuade him away from his marital commitment. A married man committed to his marriage, his love, his life with his spouse, his home and so forth has a lot to lose. The single woman who coerces him into a third- party relationship sees that through her persuasive efforts in her manipulation, he chose her, not his commitment to his marriage. Her accomplishment of luring him into the third-party relationship is an ego boost to nurture her low self-esteem. The accomplishment of winning his attention is the reward, as opposed to having a sincere healthy relationship.

Some people like toying with the energy of drama. One phone call or misplaced text message could destroy a marriage. Other women who desires a beautiful marriage sees love and happiness in the interactions of another couple. The single woman desires what that happy wife has, and pursues the husband. Fear of commitment, or simply looking for a father figure are other reasons for this type of behavior. Career women may not want the responsibility of a real relationship, but merely like the attention an affair offers [3]. There is a myriad of reasons why women do this.

Single men who have affairs with married women may lend itself to the fun of a carefree romantic relationship with no commitment on his part. A married woman with children, for example, is not available for a real relationship that involves dating, meeting each other’s friends and family. It creates a relationship for the single man, with no expectations and no responsibility. There is no need for dinner dates, remembering special anniversaries, or expenses. The focus is all about fun.

Underlying in both men and women from all walks of life, however, who intrude into committed relationships may represent a deep psychological aberrancy, as opposed to casual irresponsibility. The aim of a third-party intruder who violates the boundaries of a married couple through influence, persuasion, friendliness and so forth, is to win you or your partner’s attention. Their focus is to satisfy their personal needs and interests without consideration to either member of the marriage. There is no empathy on the part of the third-party intruder, they are manipulators.

Examples of Third-Party Manipulators

There are many examples of manipulation. Asking favors of you is an easy way to win someone’s attention. For example, the third-party person asks you to come to their house to help with a kitchen repair. Without telling your spouse you agree to help out. It seems easy enough, you’re in the neighborhood, it won’t take long, and the third-party person is just a friend or an acquaintance. While working on the repair the conversation becomes more friendly and casual. A separate personal friendship has been initiated. It seems harmless, after all, it was just a repair and conversation doesn’t hurt anything. Helping with a repair and talking is far from having an affair. It’s just being helpful to the third-party friend whom your spouse does not know you engaged upon. “No harm, no foul,” you say, you were just helping with their kitchen. This innocent thought is exactly what the third-party intruder was counting on.

Another example, the third-party person may initiate a boundary violation by confiding personal information with you while encouraging you to divulge personal information as well. What harm is that? You may think it’s of no harm. It’s just conversation and no one will hear about it anyway. The harm is, it is sharing personal information which should probably remain private anyway.

For example, during the event of that conversation, something personal comes to mind. You then view this dialogue as an opportunity to seek clarification of your thoughts, or validate your thoughts, or give you new thoughts, or help the third-party person with their thoughts. The intimacy of this situation creates a disclosure of privacy between you and the third-party. What’s wrong with this scenario is, it creates a ‘shared disclosure of privacy’ that is bonded between you two confiding private information with each other. Entrusting each other to keep that disclosure private is the bonding element between you and your new third-party friend.

Trust and bonding have now been developed with the third-party person without giving it a second thought. After all, you were only trying to help with their kitchen. Or you were just seeking answers to a thought that had been on your mind. The third-party person was friendly enough to help you and now you feel better. Feeling better gives light to the third-party intruder as a nice person whom you now feel very grateful to. Because they were so helpful to your private dilemma, you feel better. In fact, ‘you feel so much better and so grateful, you may be inclined to help them again’ is the third-party’s manipulation to further pursue boundaries with you, you may have never dreamed of.

Additionally, the third-party person with whom you helped repair their kitchen is now ever so grateful to you, ‘it would be wonderful to pay you back someday’ further sinks the hook of the third-party person’s manipulation to keep the rapport going and maintain a nice friendship with you. After all, you were so nice to help them with their kitchen. It all seems friendly and innocent is the guise of the third-party intruder manipulating every angle of the interactions. In all sincerity, you are a nice person, and now, without awareness, you are becoming a victim of their ploy.

Granted, there is nothing wrong with helping others. There is nothing wrong with appreciation when you are helped in return. When couples are specific about their boundaries for their relationship, such as no secrets, the expectations, the marriage, and third-party friendships can be very stable [3]. The scenarios above created a violation of healthy boundaries because your spouse did not know you went to the third-party person’s home, spending time alone with them to repair their kitchen. And because personal information was shared privately. Trust between you and your new third-party friend was held with an unspoken understanding that it would remain private, also created an unspoken bond between you two.

This third-party person with whom you feel good about, is in actuality, a manipulative third- party intruder, and you are not yet aware. The third-party relationship that was initiated outside the boundaries of your marriage has created triangulation. Three is always a crowd.

Another example, the third party-person may kick up a fun, flirty conversation with you at work, and asks to go to lunch with you. Perhaps they explain they have no one else to eat lunch with, and you feel sorry for them. Or they accidentally forgot their wallet and have no lunch money. Another example, the third-party person specifically volunteers to be on work projects, or committees with you to engage in that one on one connection they are seeking. The list can go on indefinitely of third-party intrusions that appear perfectly harmless.

The point is, if you do not have boundaries within your character, and/or the guidelines of your marriage you can easily fall prey to outside third-party influences before you know it [15] Why? Because you are a sentient human being interacting with another sentient human being. Feelings emerge, they are reciprocated politely or in true sincerity, and an experience ensues [5]. Covert manipulation by the third-party person may not be their deliberate intent, however, it cannot be ruled out. Having no boundaries is a perfect recipe for disaster in these precarious situations. By following healthy boundaries, and maintaining awareness, you avoid situations that may place you with possible temptation, and/or innocent, yet, painful misunderstandings with your spouse.

Emotional Affairs

In the discussion of having an affair, everyone has their definition of the term. Most people refer to the term’s affair, adultery, unfaithful, infidelity, cheating, and two-timing as sexual intimacy with another person outside of their marriage. But what about those personal outside third-party friendships that include emotional involvement without sex? It’s just a special friend with whom you confide in, share aspects of your personal life with, maybe regularly, maybe several times throughout the week, and you like their companionship. “No harm,” you say, “We’re not having sex. We’re just friends.”

When a third-party friendship is created that involves an overabundant level of interest, interacting, trust, a desiring, or a need for companionship with that third-party person that is ongoing, perhaps daily, and without any sexual intimacy. The question is, is this third-party relationship that could ‘potentially’ pose a threat to your marriage; is that a boundary violation? There is no sex. But does this third-party relationship fit in the category of unfaithful?

Yes! Because it is an emotionally based involvement with another person outside of your committed relationship, your marriage. Because the third-party person, your friend, with whom you like, trust, appreciate, and value as a friend could potentially become more than a friend, could also potentially place you at the pinnacle of sexual temptation, nevertheless. Following the path of heart, mind, thoughts, words, actions, feelings, accompanied by no sense of boundaries is the perfect formula for unfaithfulness. Faithfulness starts in your heart. Faithfulness in a marriage is, and was, initiated within the heart and mind of the beholders committed to the marriage. Betrayal may be viewed as, “Any act, or life choice that does not prioritize the commitment and put your partner before all others,” [16].

Emotional involvement with a third-party intruder separate’s marriage into an emotional triangle. It creates emotional betrayal that cuts into the heart of the marriage where love is sacred, and most importantly where your commitment was initially commenced [1]. Commitment starts in your heart. When you become emotionally involved with the third-party person, you have violated the very foundation of faithfulness where your bond with your spouse began. Additionally, when your emotions are pulled outside of your marriage towards the third- party friend, you have distanced yourself from your spouse emotionally, and from your marital commitment [1]. This gap violates the covenant of your union emotionally in your love for each other. Following the path that commitment starts with feelings in your heart, is then carried to your mind, your thoughts, words, and actions which then creates your beautiful relationship.

Unfaithfulness follows the same pattern. Most people do not awaken on any given morning and suddenly decides to have an affair with someone that afternoon. The development is a process that starts in the heart and mind way before he or she acts on it. Betrayal, stepping out of the marriage unfaithfully takes time and follows the same path of your original commitment to your spouse: heart, mind, thoughts, words, action. An affair has ensued.

Emotional involvement with a third-party person who poses a threat to your marriage is the foundation of betrayal initiating infidelity at the core of your commitment to your spouse. It is an affair. It is an emotional affair. It is a betrayal of trust, an insult to the integrity of love, marriage, and your commitment to your spouse. ‘Love, honor, cherish and forgo all others’ lays the ground rules for marriage in the commitment that is based on love for and with your partner. Nowhere does that include an additional partner on the side who also fills your heart with emotional joy, contentment, needs, reassurance, or satisfaction to fill your day. ‘I love you, Honey. But let me check in with my third-party friend to settle my day. I will then be happy to spend the rest of my evening with you,’ is relationship suicide.

By thinking of love as a verb, an action word that represents your feelings; your love is best shown to your spouse by your actions. Honoring your marriage with behaviors that protect your commitment, as in exercising healthy boundaries with third-party intruders is an act of love for your spouse and to your marriage. Emotional affairs are just as damaging as sexual affairs, and most often lead to sexual affairs anyway. Healthy boundaries avoid these sentient pitfalls of human nature, which lends the thought ‘it is best to avoid them altogether,’ instead of working through them later down the road. Not only does exercising healthy boundaries demonstrate love for your spouse and your relationship. It is also an act of respecting your own integrity. It conveys the message, ‘I am a faithful loyal person to my loved one. Do not approach me in any other manner, thank you. Now we can be friends,’ – meaning healthy friends with respectful boundaries that honor your marriage.

What Does an Emotional Affair Look Like?

Emotional affairs can be complicated because they are easy to deny when there is no sexual intimacy involved. They are easy to hide from your spouse, “We’re just friends.” Self- denial may be an easy trap to fall into; after all, there is no sex. He or she is just a friend. With all of this roundabout denial, how do you know if you or your partner is participating in an emotional affair?

Several aspects come into play that may require a discerning eye of observation, self- reflection, awareness of boundaries, and agreements made within your marriage about outside third-party friendships. Most third-party relationships begin with an innocent association with each other. Work, school, the gym, community volunteer groups, your child’s sporting events, walking the dog with a neighbor every day, or anything that entails a commonality for the interaction are perfect examples of situations where innocent friendships with a third-party intruder can develop. If your awareness of boundaries is lost, or you never had one in the first place, a personal relationship can easily evolve which may seem harmless [1]. It may remain harmless. But based on the fact that we are all sentient beings [5] leaves everyone at risk for feelings to evolve and grow [15]. Manipulative third-party intruders know this.

The damage occurs when you begin sharing personal information with the third-party person regarding your feelings, personal information about your life or your marriage that should remain private [1]. Sharing problems about your personal life, your family, or your marriage, for example, with the third-party intruder is an advertisement that you are open to receive consoling [17] and in need of a shoulder to lean on. In turn, listening to the third-party friend share their personal information with you seeking help from you, creates the role of the damsel in distress waiting to be rescued – BY YOU! It can be very tempting to help out, while it simultaneously pulls you into developing feelings for the third-party person. You feel sorry for them. You feel good about yourself to be helpful and to be needed. And, because you are not sexually intimate with the person, guilt and remorse for crossing any inappropriate lines are thrown out the window to denial.

Examples of the Emotional Affair:

There are many examples of third-party relationships that are inappropriate. Generally speaking, characteristics include an over-involvement, over and above normal communications, or unreasonable amounts of time with the third-party person that exceeds the call of duty of work, volunteering, school, or any situation may be leaning in the directions of an inappropriate third-party relationship. There is no professional, community, committee, or athletic necessity to discuss or engage in personal issues with the third-party person other than the task needed for the job, project, athletic team, or working out.

Do you find yourself, or do you see your spouse frequently communicating with the third-party person for extraneous reasons that have nothing to do with work or the committee? Consider the idea, then, that work, or the community committee project, or your child’s athletic team may now be an excuse to maintain that inappropriate third-party relationship.

Detailed Examples:

If the relationship with a third-party person is held separate from your spouse, including secrets, discrete and high frequency interacting and communicating with the third-party person, inappropriate text messages filled with flattery, personal pictures, romantic pictures, sentimental pictures, everyday pictures of your activities for the day, pictures of your family activities, sexual pictures, ongoing sharing of your personal life with the third- party person, sending pictures of the third-party person to the third-party person accompanied with comments such as, “Here’s your beautiful smile,” is flirtatious and inappropriate. Deleting or hiding text messages or emails, ongoing encouraging comments with personal moral boosting supportive type comments for the third-party friend, late-night communications such as, “Are you okay? Do you need anything tonight?” or “I’m thinking of you and you should be here with me,” are all inappropriate forms of communications with a third-party person. Verbal or physical gestures suggesting flirtatiousness are inappropriate. All of these forms of communication have nothing to do with work, volunteer projects, or your child’s athletic team. Neediness, missing the third-party person throughout the day and wanting to touch base to just say, “Hi,” is an inappropriate involvement with a third-party person. Going to their home alone and without your knowledge, followed with an excuse, “I was just trying to help with their kitchen, and Oh! – why her dad was there,” is inappropriate and may be grounds for question.

Going out of town alone with the third-party person without your knowledge or approval, followed with angry excuses of, “It was just business!” is inappropriate, hurtful and unacceptable. Communications with the third-party person that eliminates acknowledgment of your spouse, or eliminates acknowledgment of your love for your spouse, disregards or is demeaning of your spouse in any way shape or form is inappropriate. Defensive anger and excuses when confronted about the dynamics of your relationship with the third-party person, the inability to let go of the third-party person when your spouse asks you to, demonstrates emotional involvement with the third-party intruder and is inappropriate. This onslaught of examples provided here, and perhaps many more, most likely indicates an inappropriate third-party relationship. Namely, an emotional affair, if not a sexual one.

Because there is (presumingly) no sexual interaction, and there may be no sexual attraction, the underlying element of deep involvement with the third-party person, with whom your spouse cannot identify within him or herself their involvement. Their emotional involvement with the third-party person can compare to an addiction filled with denial of their behaviors that are unhealthy, destructive, co-dependent, destroys trust, and is damaging to their closest most valued relationship, your marriage. It is easy to see in others what people do not see in themselves [18]. Denial is a powerful front to hide behind yourself when, in fact, your spouse sees right through you.

Draw the Line: Third-party friendships that do not include you, or you are not including your spouse is clearly off-limits. Get-togethers, conversations, and interactions with the third- party person that are private, secret, or frequently one-on-one with the third-party person indicate that triangulation has been created in your marriage. You or your spouse may be aware of these interactions, but most likely you may not be aware of all of them. Partial disclosure of the third- party friendship is a half-truth, which means it is deceptive by the mere nature of hiding the other half. When the extent of the interaction and ongoing communication with the third-party intruder is well beyond the scope that a spouse would consider casual, or intermittent, and most definitely does not include them, the third-party relationship must change, have defining boundaries placed upon it, or removed altogether.

Why?

If your spouse is involved with someone that makes you uncomfortable for any reason and they are not sexually involved; they state to you there is no sexual attraction, why worry about it? The larger question is why do they have this third-party relationship? Why do they hang on to it when you have expressed your discomfort? Why would they need a third-party companion, a threat to your relationship when they have you?

Because they are emotionally invested! They did not utilize healthy boundaries in their behavior with their third-party relationship and now they are involved with the person emotionally. Their third-party friend has, most likely, become a very good friend, and perhaps now their best friend. They are attached to a need for the third-party person. They are having an emotional affair.

The term ‘emotional affair’ may come across as harsh when confronting your spouse who is in denial of their behavior, or never heard the term ‘emotional affair.’ To rephrase the situation as ‘you are overly involved’ might be easier to digest, but ultimately suggests the same thing. The damsel in distress and the knight in shining armor might best describe your complaint about your spouse’s involvement with the third-party relationship that is uncomfortable for you. Your spouse should be rescuing you, not someone else.

Any individual, your spouse or yourself, who is unable to say ‘no’ to others when no is appropriate is a person without personal boundaries and is a spouse who is not respecting healthy relationship boundaries either. Your spouse needs to say no to the damsel in distress because no is appropriate, and the damsel needs to move on. Not all emotional affairs turn into sexual affairs. But consider the thought that emotional involvement is the normal gateway for physical involvement and the rest is history.

Manipulative third-party people know this, and perhaps, has implemented tactics to encourage this with you, or your spouse. If you have lost sight of your marital boundaries and are involved in a third-party relationship, you are not only unfaithful to your spouse, you are most likely, also, a victim of manipulation from the third-party intruder who took advantage of a relationship with you that should have remained proper.

Painful Effects of an Emotional Affair

Considering that the third-party relationship has remained on the emotional level only, the difficulty dealing with these situations lies in the guise of ‘we’re just friends.’ It seems harmless to the spouse participating in the third-party relationship justified in the understanding there is no sexual relationship. The spouse participating in the third-party relationship may feel no sexual attraction either; nevertheless, engages in an overabundant level of interest, caring, concern for the third-party intruder, and need for their attention in return.

By nature, people are social beings with needs, interests, and activities which do not always involve the spouse. Additionally, it is fair to say that one person, your spouse, cannot fill your every need. Having outside friendships is normal, and healthy. When unhealthy circumstances evolve, however, demonstrating symptoms of an emotional affair, the spouse observing the situation is left with feelings of uncertainty, missing pieces, feeling excluded, and worried the marriage has changed. The third-party relationship, the emotional affair, is an emotional intrusion to the marriage. The heart is the foundation of love and commitment. It’s the starting point. It houses our emotions, our feelings of love and attraction, hate and disgust, and everything in between. In our committed relationship, our marriage, the heart is sacred space reserved for each other. A third- party intruder is overstepping territory that once was exclusive for you only or your spouse.

If a spouse is participating in an inappropriate third-party relationship, an emotional affair, that foundation of love, affection, and commitment in the marriage has been disrupted. That emotional space where trust, closeness, loving comfort that nurtures the marriage is no longer two people but is now shared with a third-party. Sections of that emotional sphere initially reserved for you, or your spouse is now sectioned off for someone else, and is left off-limits to the spouse left hurting [19]. Sharing that emotional space betrays the foundation of ‘love, honor, respect, and forgo all others.’ The spouse left hurting is left feeling betrayed, disrespected, threatened by the mere nature of a third-party’s presence in your heart. When the hurting spouse confronts the issue, the spouse participating in the emotional affair responds with defensiveness, ‘we’re just friends.’ Each spouse is left feeling insulted from each other [19].

The spouse left hurting did not receive reassurance that he or she was seeking. The spouse accused of the affair is taken aback by what may be deemed as a false accusation to their faithfulness, an insult to their integrity. It is pointing light on their character with question, are you faithful? Are you trustworthy? Are you honest? Are you a person of integrity? Are you lying? What do you two do together? What do you two talk about? Why am I not included? Why are you involved with this person? Are you in love with this person? Why is this friendship so important to you?’ And many more questions about their emotional world that has become closed off, now reserved for someone else. The spouse hurting is left feeling bewildered, confused, threatened, betrayed, and abandoned to defensiveness that warrants no room for comfort, cohesiveness, or emotional union in their love. Instead, the spouse left hurting is accused of being insecure, controlling, jealous, and insulting the integrity of the spouse who participates in the third-party relationship that he or she views as a harmless friend.

The discord creates a gap between the spouses, making the third-party friend appear more appealing as a friend, and now needed for emotional support. This gap in the marriage will fester if left unattended. The spouse hurting sulks in sadness, alone in their pain no longer comforted by their loved one has been hurt twice. Once with the uncertainty of the third-party’s place in your heart, and second by rejection from their loved one of their fears and worries. The spouse within the third-party relationship unable to see the inappropriateness of their involvement struggles with acknowledging the improper dynamics of their third-party relationship, the change in their marriage, their spouse, and defends their character which has now been shattered by the mere nature of question and/or accusations. Both members of the marriage end up hurt, not because hurt was intended. But because a third-party became an emotional interference in the union between two people.

A third-party person intruding into someone’s marriage is an emotional boundary violation. The emotional space in a loving marriage is between two people, not three. Not two and a half, indulging in brief contact with the third-party person for a quick emotional fix once in a while. A loving committed relationship between two people is two people only.

Why It is Unfair For All Three

The psychological imbalance in an emotional affair affects all three members, the spouse who is participating in the affair, the third-party person, and the spouse who is left hurting. Emotional affairs can evolve into a deep emotional bond with the third-party person that fills your thoughts with great appreciation for the friendship and sometimes love. Most often it includes sharing personal secrets, deep thoughts, innermost wishes, and concerns and worries. Sharing these issues with the third-party person creates a transference of intimacy that would normally be shared with your spouse. These friendships can develop innocently, or perhaps manipulatively from a deliberate intruder.

The Participating Spouse: When the hurting spouse is left out of fulfilling this intimate role within the marriage, the spouse participating in the emotional affair pulls the third-party person in to play the role of companion, confidant, and the emotionally supportive partner. The unfairness this plays on the spouse participating in this situation is, the effect causes a bifurcation of consciousness. Or, a splitting of your heart emotionally into two directions for two different people. Your spouse is the primary person you loved well enough to initially marry. Rather than dealing with improving your marriage, the arrangement of having a third-party relationship is much easier to have your cake and eat it too. In other words, two people can nourish your needs while you do very little to fulfill your own needs or the needs of your marriage. Unfortunately, however, this limits your capacity to experience deep love with your spouse. You are cheating yourself from a wholehearted loving experience by partially loving two different people.

Marriage takes a concerted effort to be a good marriage. By participating in two relationships that fill your emotional needs; you are, in reality, denying yourself the discipline and skills for maintaining a healthy relationship with one person. You are denying yourself development to be a quality partner for anyone; and, you are not working on improving your marriage. In effect, you are passively having your needs met by two different people. This lack of personal development of not dealing with the demands of a quality marriage in a healthy manner may be the result of sincere clinical denial, unable to see the dysfunction of the relationship triangle. Or, it may be plain old apathy, meaning emotional indolence.

The Third-Party: Provided that the emotional affair evolved out of innocent friendliness, the unfairness of the emotional affair for the third-party person is, they are essentially being used to fulfill your emotional emptiness. Provided that the third-party person is not having a sexual relationship with you, they may fanaticize of having an intimate relationship, perhaps a serious relationship with you when you have no intentions or desires of going down that road. This holds the third-party person stationary in their life from perusing a healthy relationship with someone else who could love them wholeheartedly, instead of part-time when you feel the need for them. Essentially, you are cheating the third-party person from a having real relationship.

On the other hand, a third-party intruder who deliberately initiated the emotional affair manipulatively may be left with boredom and frustration when the thrill of accomplishment wears off and they did not find the fulfillment they had initially fantasized about.

The Hurting Spouse: The spouse left hurting is left hurting for obvious reasons. Betrayal of trust, secrecy, dishonesty, feeling threatened of losing your love, and emotional betrayal that their spouse, you, could have feelings or love for someone else. When the participating spouse does not engage their (hurting) spouse as their emotionally intimate partner, the spouse left hurting is, unknowingly, disadvantaged to nurture the marriage or their spouse appropriately.

The hurting spouse is cheated from knowing their partner wholeheartedly because the spouse participating in the emotional affair is diverting his or her thoughts and feelings somewhere else, to a third-party person. This adds to the emotional gap between the spouses because the hurting spouse is without awareness of the true person they are married to, thus, is unable to interact with their loved one to fulfill their needs. The spouse left hurting, unfortunately, is interacting with a façade the participating spouse presents to them, because the participating spouse is hiding their true self, in addition to hiding their involvement with their third-party friend. The hurting spouse is also cheated from receiving wholehearted love from their loved one because their loved one is pouring energy into someone else, the third-party person.

The emotional pain from these experiences can be long-lasting and take time to work through. Re-establishing trust can be a slow process with experiences of ups and downs before reaching comfort with each other. Placing your spouse through the pain and challenges of an emotional affair by not exercising healthy boundaries in your behavior is an unfair lack of consideration that could have been avoided altogether. The situation neglects personal growth and development within the marriage. The overall effect of an emotional affair is that all three parties end up with an incomplete relationship.

Never too Late to Learn

Healthy boundaries protect yourself, and your marriage from unwanted influences, or painful misunderstandings, which may be sincere misunderstandings. Healthy relationships have healthy boundaries that prevent third-party intruders from overstepping boundaries that should be reserved for your marriage. Marriage is a responsibility. When we are in a loving committed relationship, we have a responsibility to hold that love in our hands with honor, respect, and appreciation. This is carried out by exercising respectful boundaries in your behavior to protect your marriage. Allowing someone to step into your emotional space is disrespectful, and deeply hurtful.

If you have never thought of healthy boundaries it is never too late to learn. Make yourself, and your marriage a work in progress for life. The willingness to grow, to make changes with yourself and your marriage not only helps you get the love you want but helps you keep the love you want [20].

Guidelines for the Healthy Boundaries Relationship Model

To set the ground rules for the Healthy Boundaries Relationship Model, the list of do’s and don’ts apply to the understanding of ourselves as sentient human beings. No one gets married with the commitment of ‘I will betray you.’ The commitment is to love, honor, cherish, and forgo all others. While there is nothing wrong with healthy third-party relationships, honoring your marriage should always come first. It starts by exercising respectful boundaries in your behavior.

The Model

First and foremost, start with having a conversation with your loved one about your relationship. Nothing underscores the importance of communication. Decide where you draw the line with third-party friends [7]. When developing your relationship consider creating a relationship notebook, so you can jot down your agreements. This is not a legal binding contract. It is a friendly note pad of your thoughts, feelings, and decisions you make together to keep you on track of ‘the marriage comes first policy,’ and to not forget what you talked about.

Cultivate friends that each of you enjoys socializing with together. Invite the third-party friend, and their partner to become friends with your spouse [21]. If your third-party friend is single, your friendship with that third-party person should change when you enter your committed relationship, your marriage. You are no longer a single person readily available for personal activities that may have once been a part of your casual friendship.

Your third-party friend should understand this without explanation. However, some people need direction.

If there is a third-party relationship that already makes you, or your spouse uncomfortable, nip it in the bud immediately. Do not deliver, or accept any excuses to rationalize or defend the third-party relationship [21]. Your marriage comes first over and above anyone else. Set defining guidelines on how to manage the third-party relationship. It may involve simply ignoring the third-party person. It may require a conversation, a letter, a meeting between the three of you to set healthy boundaries or eliminate the third-party relationship altogether. Whatever is initiated to change the dynamics of the third- party relationship, has to be carried out, and most definitely, maintained.

If your spouse is uncomfortable with your third-party relationship and setting boundaries is not an option, complete disengagement from the third-party relationship may be the only option. There is no one more valuable in your life than your loved one, your spouse. A friend, the third-party friend who is truly a friend ‘only’ should respect that, knowing that their friendship with you is just a friendship. Not a personal selfish need of theirs to have you, or your spouse at their disposal for their personal interests. If the third-party person knows that you or your spouse is uncomfortable, they should be respectful; back off, apologize, make corrections, or stay away altogether. The third-party friend should respect both of you as a couple because you are a couple, not a single.

The spouse in question also has a responsibility to reassure their partner that boundaries with the third-party person are being maintained. This may require personal conversations, or an open pass to see text messages, cell phone call logs, or emails. Everyone has their limit of sharing, and most especially passwords. So, consider this a boundary issue in your marriage as well. Instead of free reign to see texts and emails, perhaps the openness of the spouse to randomly show you when you ask may be a polite option to open that boundary between you two. Transparency is a fabulous passage for building and maintaining trust.

Do not cultivate private relationships with third-party people who may pose a threat to your marriage in anyway shape or form. Instead, cultivate relationships with other couples, or friendships that offer no means of threat of any type. Heterosexual married people can cultivate close friendships with others of the same sex; who can, and may become your best friend outside your marriage [21]. This rule holds true for any type of committed relationship between two people who love each other. Define this for yourselves in your lifestyle and your marriage.

With co-workers, civic committee members, volunteer members, other parents of your child’s class or group, your child’s teacher, your neighbor, or anyone who has the potential to cause havoc in your marriage or risk the potential of overstepping healthy boundaries, should be addressed in the confines of their appropriate role. If it’s a co-worker stick to business [22]. If it’s a committee member, stick to the committee agenda and so forth. Avoid developing personal or private relationships, but create open relationships that include your spouse and the third-party’s loved one as well.

Specifics: Specific guidelines are for you and your spouse to consider: Do not go out to lunch, dinners, or happy hour drinks alone with a third-party person co-worker. Go as a group [1]. Do not meet alone with third-party people if possible. Have your office door open, or an office with blinds open if possible [7]. Do not go out of town with a third-party person alone [1] and probably not as a group either. Let that person make their own way to their destination.  Consider taking your spouse with you when you go out of town for business or community projects that require travel. When you do travel out of town alone, make a point of calling your spouse every evening to check-in, or perhaps video chat. Offer reassurance of your love for them, and that you miss them. Rather there is an issue about boundaries or not, a little reassurance goes a long way to keep your marriage strong.

Be cognizant of a third-party intruder who demonstrates overly friendly gestures or flirting. Don’t feed into it. Ignore it, or tell the person you are uncomfortable. Do not deliver overly flattering comments that may come across as affectionate or flirtatious. Appropriate compliments have their natural place in all appropriate settings, so leave them there. Do not participate in conversations where you or the third-party opens the door for personal information. The privacy of your marriage is sacred space. Respect it and keep it private. Your problems with your spouse belong to you and your spouse, they are none of the third-party person’s business. Speak politely and kindly of the person you love to show the third- party person you are devoted to your spouse. Do not allow anyone to speak badly of your spouse with negative comments or name-calling. Always defend your spouse and inform the third-party person that insults and name-calling of any type are not acceptable in this manner. For the damsel in distress who needs your ear, encourage them to talk to the person they have the issue with, or get professional help [7]. You are not their therapist, and they are not yours either.

Do not keep secrets from your spouse at any time about your relationship, your feelings, or your interactions with a third-party friend. If you see that you are developing feelings for someone outside of your marriage talk to your spouse, or a therapist, but not the third-party person. Do not participate in personal private communications with the third-party person. This includes text messages, emails, private messages, any social media, Drop Box, video chats, or passing notes to each other at the office unless you are completely at ease to share it with your spouse. If your spouse becomes uncomfortable for reasons you did not anticipate, stop the communications. Take action to inform the third-party person that the private messages have to stop. Be honest with yourself about this and take care of it. If necessary, show your spouse that you took care of it and that there are no more communications. If communications cannot be discontinued for some reason, such as ex-spouses where children are involved, or other situations, see if copies of future correspondences can be openly shared with your spouse like a group text, or group email exchanges.

When out together and the third-party person is present with others, and/or a group event, avoid private dialogue with them that excludes your spouse. Include your spouse on the topic of the conversation that he or she may not understand if it is work-related for example. Or, avoid the third-party person altogether so you and your spouse can have a good time.

Reflect: Reflect inwardly. Are you feeling attracted to a third-party person? Do you think about them often, or compare them to your spouse? Would you be comfortable with your spouse doing any of the things you are doing with your third-party friend, that your spouse does not know about? Are you upholding your spouse’s requests? Or does the influence of your third- party relationship sway you from doing so? Do you and your third-party friend talk about your feelings for each other? Do you share your feelings and thoughts with your third-party friend more than your spouse? Do you isolate your third-party friendship away from your spouse? Do you feel sorry for the third party-person in such a way of taking on co-dependent behaviors to rescue them, to fix them, or fix their problems? Are you delivering excuses, defending your rationale for maintaining your third-party relationship when your spouse is uncomfortable, or highly upset about it? Is your third-party relationship coming between you and your spouse? Are you arguing about it? Has your committed relationship, your marriage broken up because of your involvement with a third-party friend?

If you answered yes to any of the above questions, you are in an inappropriate relationship with a third-party person. You are having an emotional affair, if not a sexual one. You are responsible for how you interact with others and how you allow them to interact with you. Be accountable for yourself as you would expect your spouse to do the same, and end the third-party relationship immediately. If your spouse is uncomfortable, do not dismiss their concerns. A wise person listens and respects the feelings of their loved one. Your marriage comes first, not the damsel in distress who can’t take care of him or herself emotionally, physically, financially, or in any manner. The same holds true if you are the one that is uncomfortable observing your spouse having a third- party friendship. Trust your intuitions! Confront your thoughts and your spouse honestly. Sooner is probably better than later.

Honesty: If you are in an affair of any type be honest with yourself. Be honest with your spouse. Honesty takes courage. As hard as it may be to face the embarrassment of confession and the fear of their reaction, it is much better to share the truth with your spouse than for them to find out otherwise. In many cases, the development of an outside friendship is not the insult to your spouse. It is the secrecy, the half-truths, and deception that betrays trust in your marital relationship that is most hurtful because it is a disregard for your spouse. And most especially, it ruins your character. It ruins the ‘good’ you with whom they knew and loved, which has now been lost to the pain of betrayal and the melting of trust that once embraced you both so lovingly.

Integrity starts with yourself. It belongs to you, so manage it in the best way possible. If you are afraid to be honest with your spouse about your feelings for your third-party friend, your emotional involvement, or sexual involvement, take comfort in the thought that your honesty may be a pivotal point in changing your marriage for the better. Your spouse will most likely be unhappy with the news, but they may ultimately respect you for finding the courage to be honest [23]. Honesty upholds the status of your integrity. Own it! Be honest with yourself and your spouse, because honesty may be your only option for staying in your marriage to make it work. Regardless of your spouse’s response, it goes without saying, change will occur.

You have been Confronted? If you have been confronted by your spouse about a third- party relationship that makes your spouse uncomfortable, fix it! Basic human nature needs to be social and have friends is not the insult. It’s the denial of your overabundant involvement. It’s the inability or refusal to make corrections with yourself to honor your spouse’s feelings that is insulting. To not make corrections with yourself and your third-party friendship is an insult not only to your spouse, but is insulting to your marriage, and yourself as well. Your marriage and your love for your spouse comes first over and above your excuses to rationalize your third-party friendship while denying your spouse’s requests and feelings. Take time to nurture your marriage. Address your concerns with your spouse constructively. Be respectful. Be trustworthy. Show trust with your actions that demonstrate faithfulness, protection of your marriage, and your love for each other. Address issues in your marriage that caused you to seek emotional solace outside of the marriage. Quality communication, sharing your thoughts and feelings, and personal interests may have been missing, and this is an opportunity to restore these things to your marriage. Your marriage comes first over and above anyone, and most especially to a third-party intruder.

Recommendations

There is much to learn about the frequency of emotional affairs and the dynamics that lead up to it. It is recommended that more research continue in the social-psychological sciences, and amongst marriage counselors to determine a set classification of symptoms and patterns of this heart-shattering relationship dynamic. The focus is to better help the spouse in distress who does not understand the behaviors, feelings, and the psycho-dynamics of their loved one who appears to be involved with a third-party person emotionally, yet, not sexually. For the spouse in question involved in a third-party relationship, who, perhaps, might be in denial; research and open discussions are avenues to guide that spouse to awareness of their actions and further self- reflection. More awareness of this topic through public forums, social media, and discussion panels will help educate the public to understand emotional affairs, third-party relationships, and preventative measures before they occur.

Conclusion

There are many philosophies, theories, and relationship models that emphasize techniques for putting your marriage first. Healthy Boundaries Relationship Model is only one perspective to do so. How you gauge your boundaries is a private decision between you and your spouse. This model merely provides guidance to help you define who you are, who you are as a couple, how to avoid manipulation, and how you hold your marriage together with happiness. In any situation, however, be your best. Be wise, discerning, and put your marriage first.

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Do’s

Don’ts
  1. Communicate! Discuss with your partner boundary guidelines that work for both of you. Make a list, write it down.
  2. Cultivate mutual friends.
  3. A single third-party friend should become a mutual friend to each of you, and spend time with both of you only.
  4. If the third-party friend has a partner, invite everyone together as a group.
  5. Make necessary changes in any third- party relationship if your spouse is uncomfortable. Set agreeable boundaries that are respectful to both of you.
  6. Reassure and show your spouse that these boundaries are being maintained.
  7. Create your closest friendships with people that do not threaten your spouse, such as members of the same sex, or opposite sex, depending on your lifestyle.
  8. Keep conversations professionally appropriate to work related topics, committee, community, or volunteer projects only.
  9. Professional engagements, lunches, dinners, drinks should be in groups only.
  10. Travel alone for business, or groups, or with your spouse.
  11. Keep compliments and acknowledgments to others appropriate for the circumstance.
  12. Speak honorably of your spouse to everyone, especially someone who appears flirtatious or interested in you.
  13. For third-party intruders who come to you with their personal problems, inform them you are not a therapist. Encourage them to seek appropriate help elsewhere.
  14. Be honest and open with your spouse at all times. Transparency opens your relationship to love and closeness.
  15. At social gatherings include your spouse in conversations they may not understand. If necessary, avoid socializing with the third-party person at events.
  16. Reflect. Be honest with yourself. Ask yourself if you are overly involved with someone in such a way that it is causing conflict in your marriage.
  17. Listen carefully to your spouse. Be receptive of their needs and requests.
  18. Be honest with your spouse in every way.
  19. If an affair has occurred, talk it out. Apologize, find forgiveness if possible. The marriage doesn’t have to end, but change must occur. Try to work things through if possible.
  20. Put your marriage and your love for your loved one first.
  1. Do not ignore this issue with your spouse when it needs to be made clear.
  2. Do not separate your spouse from your friends, or hang out with previous single third-party friends as if you are still single.
  3. Do not allow third-party friends to encourage alone time with you. You’re not single anymore, you’re in a committed relationship.
  4. Do not exclude the third-party’s partner.
  5. Do not violate established boundaries that have been agreed upon.
  6. Do not hide information from your spouse, or disregard their feelings.
  7. Do not create best friend relationships with any third-party person that poses a threat to your marriage per your lifestyle.
  8. Do not engage in private, personal conversations with a third-party person that is unrelated to work, community, or social projects.
  9. Do not go out to lunch, dinner, drinks, or happy hours alone with a third-party person.
  10. Do not go out of town alone with a third- party person.
  11. Do not flirt or come across as overly flattering with others, and do not allow others to flirt with you.
  12. Do not complain about your spouse. Do not allow others to speak badly about your spouse either. Always hold their honor.
  13. Do not allow a third-party intruder to share their personal problems with you. Refrain from getting involved with their life drama and problems. And do not share personal information about your marriage with a third-party person.
  14. Do not engage in secrecy or hide a relationship from your spouse.
  15. Do not exclude your spouse from business conversations when socializing with groups that include the third-party person.
  16. Do not allow your feelings to develop for someone else. Do not hide this from your spouse if it has already occurred.
  17. Do not disregard your spouse’s feelings, worries, or insecurities.
  18. Do not deny the truth of your involvement with a third-party person that is causing problems in your marriage. Be honest with yourself and your spouse.
  19. Do not loose site of your marriage, and the depth of your loving relationship in spite of problems.
  20. Do not prioritize anyone over and above your spouse or your marriage.

References

  1. Cherry D (n.d.). Emotional affairs. Series about: Affairs and Adultery. Focus On The Family.
  2. Admin A (2014) Boundaries loving again after a pathological relationship. USA.
  3. Tartakovsky M (2018) Why healthy relationships always have boundaries & how to set boundaries in yours. Psych Central.
  4. Tatkin S (2011) Wired for love. Oakland, CA: New Harbinger Publications. USA Today. (1996, August). Many single women prefer married men. USA Today, 125.
  5. Ramsay K Life coaching certificate course (beginner to advanced). Udemy.
  6. Katherine A (1991). Boundaries where you end and where I begin. Center City, MN: Hazeldon.
  7. Caston M (2017) How to keep boundaries with the opposite sex.
  8. Cloud H, Townsend J (2000) Boundaries in dating. Orange, CA: Yates & Yates.
  9. Cloud H, Townsend J (1999) Boundaries in marriage. Orange, CA: Yates & Yates.
  10. Grant A (2014) Seven sneaky tactics that sway. Psychology Today 47: 43–44.
  11. Harrary K (1992) The truth about Jones town. Psychology Today 25: 62.
  12. Sarkissian H (2017) Situationism, manipulation, objective self-awareness. Ethical theory & Moral Practice. 20: 489–503.
  13. Noggle R (2017) Manipulations, salience, and nudges. Wiley Bioethics.
  14. Potter N (2006) What is manipulative behavior, anyway? Journal of Personality Disorders 20: 139–156.
  15. Daly J (2014) Keeping healthy boundaries. The Winnipeg Sun.
  16. Gottman J, Silver N (1999) Chapter 2 What does make marriage work. The seven principles for making marriage work (2ndedn). (p. 26). New York, NY: John Wiley & Sons, Inc.
  17. Mental Health (n.d.) Just answer mental health.
  18. Parr A (n.d.) Opposite sex friendships? Allen Parr Ministries.
  19. Lustbader W (2014) Emotional affairs: Why they hurt so much. Psychology Today.
  20. Hendrix H, Hunt H (1998) Getting the love you want. A guide for couples. New York, NY: Henry Holt and Company.
  21. Focus On The Family (n.d.). The Billy Graham rule: Should you be friends with someone of the opposite sex? Focus On The Family.
  22. Eckel S (2019) The power of boundaries. Psychology Today.
  23. Christy H (2017) The importance of being honest in marriage.

UK Specialists’ and GDPs’ Use of Systemic and Local Antimicrobial Administration in Periodontal Therapy: A Questionnaire Study

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DOI: 10.31038/JDMR.2020312

Abstract

Aim: The aim of the present study was to evaluate the use of antimicrobials, the prescription patterns and the reason(s) for prescribing antimicrobials when treating periodontal disease in selected UK General Dental Practitioner (GDP) and Periodontal Specialists.

Materials & Methods: The questionnaire consisted of 21 questions and was sent to 488 Periodontal Specialists and 488 GDPs. Data management and analysis was performed using Microsoft Excel, SPSS® version 22.0 software and frequency distributions, cross tabulation tables and graphs were constructed from the data. Any association between variables was tested at the 5 % level of significance (P≤ 0.05).

Results: The questionnaires were completed by the Specialists (38.72%) (n=189) and 23.36% (n=114) of the GDPs.  The results indicated that the use of systemic and local antimicrobials followed the current guidelines. Specialists prescribed more systemic antimicrobials than the GDPs, although Specialists limited the use of local antimicrobials. The GDPs reported that decision making was difficult when to use local antimicrobials although recognised that using local antimicrobials were more effective than root surface debridement alone. Other reasons for using antimicrobials were based either on the patient request or patient satisfaction with the treatment. Lower frequency of antimicrobial use was reported in regeneration and implant procedures by both Specialists and GDPs although the Specialists were more inclined to use antibiotics/antimicrobials in these procedures.

Conclusions: The results of the study suggested that there was a need for dentists to follow current guidelines when prescribing antibiotics/antimicrobials in order to avoid unnecessary prescriptions, antibiotic resistance and adverse drug reactions.

Keywords

Adjunctive Use, Antibiotic Prescribing, Evidence-Based Guidelines for Prescribing, Management, Periodontal Diseases

Introduction

The effectiveness of adjunctive antimicrobial or antibiotic therapy in periodontal disease and implant placement has been strongly supported in the published literature [1-3]. However other studies both in the United Kingdom (UK) and in countries outside the UK have reported that antibiotics/antimicrobials may be inappropriately prescribed and used by dental practitioners [4-11].  Several investigators have also reported on the effect on non-clinical factors such as requests or demands from patients [8, 10]. From these studies it was evident that there is a need to not only to provide both General Dental Practitioners and Specialists with clear and concise guidelines on what and when to prescribe appropriate antimicrobials/antibiotics together with the correct dosage and duration of use but also the need to continually update their knowledge in attending continuing professional education courses and basing their prescribing habits on evidence-based clinical practice [7-8]. According to Gillam & Turner [12] the importance of current and updated recommendations and guidelines on the appropriate use of antibiotics/antimicrobials in general dental practice cannot be underestimated.  More recently several tool kits and guidance notes on dental prescribing have been made available such as the SCECP Scottish Drug Prescribing for Dentistry and the NHS England Public Health England Dental antimicrobial stewardship: toolkit. [13-14]

Materials and Methods

Aims and Objectives

The objective of present study was to evaluate the use of antimicrobials, the prescription pattern and the reason(s) for prescribing antimicrobials when treating periodontal disease in selected UK General Dental Practitioner (GDP) and Dentists who were on the Specialist list for Periodontics or who expressed an interest in Periodontics.

Questionnaire Design

The present study questionnaire was modified from Choudhury et al. [8] based on pre 1999 guidelines in order to implement the changes in the American Academy of periodontology (AAP) [15-16] classification and was assessed by the Queen Mary University of London (QMUL) Research Ethics Committee (QMREC1047) with the conclusion that no ethical concerns were present and the proposed study was considered to be of an “extremely low risk”. The questionnaire consisted of 20 questions which were mainly closed questions. Questions 1-4 requested the demographic data by identifying the age, gender, the years since graduation, and the type of practice. Question 5 requested information in relation to the amount of time allocated by the participants for root surface debridement for each quadrant and whether any local anaesthesia was used. Question 6 related to a question whether the participants prescribed local or systemic antimicrobials for periodontal conditions. Questions 7-11 attempted to determine the indications of use of the antimicrobial in periodontal diseases, and Questions 12-18 aimed to gain information about decision making in the choice of local/systemic antimicrobials in treating periodontal conditions, rationale for use or not using and whether the treatment was success/unsuccessful.  Questions 19-20 determined to obtain the information of attendance on courses on antimicrobials in periodontal therapy, as well as information on whether the respondent was a Member of a Specialist Society. The questionnaire consisted of four A4 pages. An introductory letter for participants was sent with each questionnaire together with a stamped address or prepaid envelope for those participants responding by the postal service (Royal Mail).

A pilot study using a cross-sectional self-administered questionnaire preceded the main survey in April 2013, during which time 100 questionnaires were given to dentists of different clinical disciplines. The participants were either staff members or postgraduate students working or studying in the Centre for Adult Oral Health at the Bart’s and The London School of Medicine and Dentistry, QMUL, London UK. The pilot study lasted for approximately 3 months (January to March 2013). The initial analysis of the pilot data enabled the investigators to check whether any clarification of the questions or improvement final layout of the questionnaire was required prior to distribution to practicing dentists on the GDC Specialist List or the General Dental Practice List. The selection of the practices for the present study was based on the available lists of Dentists from either the Specialist of Periodontics List or selected General Dental Practitioners (GDP) on the General Dental Council (GDC) Register respectively. The final version of the cross-sectional self-administered postal questionnaire survey was completed following very minor administrative revisions such as typographic errors prior to distribution. The practitioners on the Specialist list (388) were sent a questionnaire by Royal Mail. (A further 100 questionnaires were also distributed by EAP in April 2013 at a British Society of Periodontology (BSP) Conference in Manchester UK; and a randomized matched sample using addresses of General Dental Practitioners (GDP) on the GDC Register (488) were generated using a randomised number generator (RNG) (GraphPad Software Inc. 2002-2005). Due to time constraints a four-month period was allowed for to enable the participants to respond, no subsequent reminders were sent for those who did not response within this period. All completed questionnaires returned within the four-month period were included in the final analysis.

Statistical analysis

Data management and analysis was performed using both Microsoft Excel (Microsoft Office 2010) and SPSS® (version 22.0 software, IBM, Portsmouth UK) and Microsoft word 2010. Frequency distributions and cross tabulation tables were constructed and graphs for this data were plotted using Excel and Word software. For the description of median, standard deviations, minimum and maximum values for continuous data and frequencies and relative frequencies (proportions) for categorical data were also calculated. Statistical analysis performed on data from the returned questionnaires included both parametric and non-parametric tests and the significance level was set up at α = 0.05 (95%). Non-parametric tests were used if the data did not follow normal distribution. For categorical data, non-parametric tests were also used (Figure 1). Analysis performed included the following:

Steps of Data Analysis

JDMR 2020-303_David Gillam

Figure 1. Flow Diagram: Steps in Data Analysis.

  1. Calculation of mean values of age and years since graduation together with standard deviations
  2. Estimation of frequencies of answers for each question indicating categorical data
  3. A Chi-square test was performed in order to assess the association between two categorical variables, e.g. the relation of treatment chosen to the level of dentist’s interest
  4. Mann-Whitney tests were performed in order to assess the association between a continuous and a categorical variable, e.g. ease in decision making in using systemic or local antimicrobials and the General Practitioner/Specialist Periodontist status.

Data analysis from the present study was compared, where possible, to data from the original Choudhury et al. [8] study.

Results

Frequency distribution of the study participants

350 participants: 47 (13.4%) participants from the pilot study and from the main study 114 (32.6%) participants from General Dental Practice and 189 (54%) participants who were either on the Specialist List or who expressed an interest in Periodontology were included in the final analysis of the data.

Characteristics of the pilot study participants

The pilot study population included dentists of different clinical disciplines who were either staff members or the postgraduate working or studying in the Centre for Adult Oral Health at the Bart’s and The London School of Medicine and Dentistry, QMUL, London United Kingdom, the sample population (n=47) was investigated. 100 questionnaires were handed out to the Dentists, and 57 questionnaires were returned (57%), of which 10 were incomplete or indicated as being not applicable to the individuals’ practice. In total 47 (47%) of the returned questionnaires were entered into the data set.

Demographic characteristics of the main study participants

The main study population included the Specialists (n=189) and GDPs (n=114) in the United Kingdom. A total sample population (n=303) was included in the main study.

Frequency distribution of the questionnaires of the main study population

In total 488 questionnaires sent out to the GDPs, and 119 questionnaires were returned (24.39%), of which 114 were usable (23.36%) and entered into the data base (Five participants reported that they had either, retired or that the questionnaire was not applicable to their practice).

The distribution of the questionnaire was in two parts: 1) 388 questionnaires were sent out to the Specialists in the Specialist list, and 109 were returned of which 98 were entered (11 questionnaires were either incomplete or not applicable to the individuals’ practice); 2) 100 questionnaires were handed out by EAP to the Specialists attending a British Society Meeting (BSP) in Manchester. Ninety-one (91) questionnaires were returned and completed. In total, 200 questionnaires (40.98%) were returned, and 189 (38.72%) were entered into the data set.

Age and years of graduation of the main study population

 The mean age of the 245 participants was 44.8 years (SD +/-11.96 years; age range 23-70 years, missing value 58). The mean years from graduation was 21.04 years (SD +/- 11.6 years; n=302, one missing value, range 1-48 years).

Gender distribution of the main study population of the GDPs and Specialists in the United Kingdom

The gender distribution of the main study population of the GDPs and Specialists were reported namely M:111/189 (58.73%); F:78/189 (41.27%) in the Specialist Group and M: 80/114 (70.18%); F 34/114 (29.82%) in the GDP Group.  The Specialist members therefore significantly comprised more females 41.27% (n=78) whereas the GDPs population comprised more males 70.18%% (n=80) (p=0.046).

Specialist membership in the main study population

85.56% (160, two missing value) were Specialist members whereas 14.91% (n=17) were GDPs. 85.09% (n=97) GDPs were not on a Specialist list. 14.44% (n=27) of participants who were Specialists reported that they did not have Specialist membership. Regarding the British Society Periodontology membership, 80% (148, four missing value) of specialist participants reported that they were members of the BSP and only 4.39% (n=5) of the GDPs were BSP members. Of those who were not members of the BSP 20% (n=37) were Specialists and 95.61% (n=109) were GDPs.

Lecture or course attended in systemic or local antimicrobial in periodontal therapy

A clear difference between the Specialist and GDP participants was observed when the participants were asked about their attendance on periodontal therapy lectures or courses in systemic and local antimicrobial therapy. There was a higher number of Specialist participants attending systemic [89.73% (n=166, six missing value)] or local antimicrobials in periodontal therapy, [76.50 % (n=140, six missing value)] compared to the GDP response [49.56 % (n=56, one missing value for systemic courses and 42.98 % (n=49, one missing value attending local delivery courses (p=0.0005 for both systemic and local delivery). One Specialist participant indicated that they gave a lecture on both systemic and local antimicrobial therapy in periodontal therapy.

Periodontal management

Duration allocated for root surface debridement (RSD) of an involved quadrant of 6-7 teeth of the main study population of the GDPs and Specialists in the United Kingdom

In relation to the allocation time for root surface debridement (RSD) duration of an involved quadrant of 6-7 teeth, GDPs tend to spend less time in RSD 51.33% (n=58) which was only up to 30 minutes. Whereas 27.03% (n=50) Specialist participants and 6.19% (n= 7) GDPs allocated up to 60 minutes for a quadrant. None of the GDPs reported spend more than 60 minutes for RSD whereas only 2.70% (n= 5) of Specialists reported that they spent more than 60 minutes (Table 1).

Table 1. Duration allocated for root surface debridement (RSD) of an involved quadrant of 6-7 teeth of the main study population of the GDPs (n=113) and Specialists (n=185) in the United Kingdom.

Item

Specialist society/list

N (%)

GDP

N (%)

P value

Up to 30 minutes

45/185 (24.32)

58/113 (51.33)

0.0005

Up to 60 minutes

50/185 (27.03)

7/113 (6.19)

>60 minutes

5/185 (2.70)

0/113 (0.00)

Frequency of participants routinely administer local anaesthetic (LA) for RSD procedure of the main study population of the GDPs and Specialists in the United Kingdom

When asked whether they would routinely administer a local anaesthetic (LA) for RSD procedures a higher number of Specialist participants 88.77% (n=166, two missing value) indicated that would tend to administer LA for RSD procedures compared to GDPs 62.39% (n=68, five missing value) (p=0.0005).

Frequency of the type of periodontal disease treated

All the Specialists 100% (n=188) and GDPs 100% (n=114) had observed patients with chronic periodontitis in their clinic.  A higher number of GDPs had observed gingivitis cases 99.10% (Table 2) (n=109) (p=0.061), apical periodontitis 84.90% (n=90) (p=0.099), and NUG 93.70% (n=104) (p=0.524) than the Specialist members however the difference was not significant. Whereas the Specialist members had treated aggressive periodontitis 94.14% (n=177) (p=0.0005), and unresponsive sites 90.10% (n=164) (p=0.0005) more than the GDPs.

Table 2. Frequency of the classification of periodontal disease treated of the main study population of the GDPs and Specialists in the United Kingdom (Please note the various descriptive terms to describe periodontal diseases has recently been reclassified).

Item

Specialist Society/List
N (%)

GDP
N (%)

P value

Gingivitis

168/177 (94.90)

109/110 (99.10)

0.061

Chronic periodontitis

188/188 (100)

114/114 (100)

ns

Aggressive periodontitis

177/188 (94.14)

78/106 (73.60)

0.0005

Apical periodontitis

139/181 (76.80)

90/106 (84.90)

0.099

Necrotising ulcerative gingivitis

171/184 (90.48)

104/111 (93.70)

0.524

Unresponsive sites

164/182 (90.10)

46/100 (46.00)

0.0005

Use of systemic and local delivery antimicrobials

Frequency of the use of systemic and local delivery antimicrobials: In general, more Specialist Society/List members reported that they had prescribed systemic antimicrobials as compared to the GDPs, whereas the local delivery antimicrobials were more frequently used by the GDPs compared to the Specialist Society/List members in treating the different types of periodontal diseases. Regarding the use of systemic antimicrobials, the Specialist Society/List members would more frequently use this type of antimicrobial therapy to treat aggressive periodontitis 76.90% (n=143, p=0.0005), and unresponsive sites, 33.16% (n=64) (p=0.008). Only one (0.57%) and (0.93%) of the Specialists and GDP used this antimicrobial therapy in gingivitis respectively (p=0.140).

Regarding local antimicrobials, a small number of Specialist members 2.22 % (n=4) and GDP 4.80% (n=5) opted to use antimicrobial therapy in gingivitis respectively (p=0.005). There were no significant differences in the number of participants from both groups who opted to use local antimicrobials in chronic periodontitis, 17.43% (n=19) GDPs and Specialist members 9.44% (n=17) (p= 0.013, missing value 14).  There was no difference in the frequency of GDP 20.00% (n=17) who used local antimicrobials to treat sites and the Specialist members, 15.73 % (n=28). (p=0.0.395) (Table 3).

Table 3. Use of systemic and local delivery antimicrobials in periodontal therapy by GDPs and Specialists in the United Kingdom.

Item

Specialist Society/List

GDP

P value

Number

(%)

Number

(%)

Use of systemic antimicrobials

Often/routinely for gingivitis

1/174

0.57

1/107

0.93

0.140

Often/routinely for chronic periodontitis

11/184

5.98

5/112

4.46

0.404

Often/routinely for aggressive periodontitis

143/186

76.90

36/100

36.00

0.0005

Often/routinely for apical periodontitis

30/154

19.50

32/101

31.70

0.003

Often/routinely for necrotising ulcerative gingivitis

138/177

77.97

89/108

82.41

0.603

Often/routinely for unresponsive sites

64/177

33.16

18/79

22.78

0.008

Use of local antimicrobials

Often/routinely for gingivitis

4/180

2.22

5/104

4.80

0.005

Often/routinely for chronic periodontitis

17/181

9.39

19/109

17.43

0.013

Often/routinely for aggressive periodontitis

32/182

17.58

19/99

19.19

0.101

Often/routinely for apical periodontitis

4/173

2.31

8/95

8.42

0.0005

Often/routinely for necrotising ulcerative gingivitis

10/177

5.65

20/103

19.42

0.001

Often/routinely for unresponsive sites

28/178

15.73

17/85

20.00

0.395

Frequency and percentages of the Specialist Society/List vs. GDPs who prescribed antimicrobials in regenerative and implant procedure: The GDP group opted for prescribed antimicrobials in regenerative procedures 13.08% (n=14, nine missing value) or implant procedures 22.22% (n= 24, 9 missing value) less frequently as compared to the specialists (p=0.0005). Almost half of the Specialist members prescribed antimicrobials in regenerative procedures 45.60% (n=83, 12 missing value) or implant procedures 46.93% (n=84, 12 missing value).

Frequency of success perceived by the Specialist and GDP participants in the use of systemic and local delivery antimicrobials (often/routinely, very successful): Systemic antimicrobials as an adjunctive treatment was perceived to be a successful treatment by 78.33% (n=141, missing value 56) of the Specialist members compared to the GDP response [62.73% (n=69, 27), p=0.016]. In regard to local antimicrobials, the Specialists 25.55% (n=35, missing value 56) were less inclined to consider that antimicrobial therapy was successful as compared to the GDP response 32.58% (n=29, missing value 27) however this was not significantly different, p=0.172.

Ease in the decision-making process when using systemic antimicrobials in periodontal therapy: 97.88% (n=185) of the specialist members reported a median of 8 (0-10 scale) for the ease in making decision in systemic antimicrobial therapy whereas 98.25% (n=112) of the GDPs reported a median of 6 (p=0.0005, missing 6). Regarding the ease in the decision making process when using local antimicrobials, 92.60% (n=175) Specialist members reported a median of 8 (0-10 scale) whereas 94.73% (n=108) of the GDPs reported a median of 6 (p=0.0005, missing 28).

Stated reasons to use or not to use local antimicrobials: Of those using local antimicrobials, 65.85% (n=54) GDPs stated that a reason for use was the superiority of root surface debridement alone (p=0.0.50) whereas 27.63% (n=21) stated that the reason for use was more cost effective than any of the other options (p=0.333). The GDPs more frequently stated several reasons for this option namely 1) to avoid the need for surgery 56.41% (n=44) p=0.257, 2) patient requested the treatment 31.65% (n=25) p=0.011, and 3) patient satisfaction with treatment 53.25% (n=41) (p=0.0005).

In regard to the reason for not using local antimicrobials, the most commonly stated reasons were: 1) no need (Specialist members 74.13% (n= 106), GDP 66.67% (n=52), p=0.002, and 2) the lack of supporting research data (Specialist members 74.32%, GDP 55.70%, p=0.001. The lack of postgraduate training locally was also a reported discouragement for GDP 64.56% (n= 51) but was not for Specialist members 22.30% (n=31), p=0.0005 (Table 4).

Table 4. Stated reasons to use or not to use local antimicrobials in the main study population of the GDPs and Specialists in the United Kingdom.

Item

Specialist Society/List

GDP

 

P value

Number+

(%)

Number+

(%)

Stated reasons for using local antimicrobials

More effective than RSD alone

66/129

51.16

54/82

65.85

0.050

More cost effective than other options

27/129

20.93

21/76

27.63

0.193

Keen to try new treatment options

38/120

31.67

41/78

61.20

0.049

Avoids the need for surgery

57/127

44.88

44/78

56.41

0.257

Patient requests the treatment

16/124

12.90

25/79

31.65

0.011

Patient satisfaction with treatment

30/123

24.39

41/77

53.25

0.0005

Stated reasons for not using local antimicrobials

Cost

52/143

36.36

39/83

46.99

0.271

No need

106/143

74.13

52/78

66.67

0.002

Practicality of usage

47/140

33.57

43/76

56.58

0.011

Unsuccessful previous usage

60/138

43.48

40/75

53.33

0.404

Lack of supporting research data

113/152

74.32

44/79

55.70

0.001

Lack of postgraduate training locally

31/139

22.30

51/79

64.56

0.0005

Medico legal

10/136

7.35

12/71

16.90

0.103

Parameter of judgment of treatment success with antimicrobial therapy

The reduction in probing depth was judged to be the most frequent parameter for treatment success with antimicrobials by Specialist members 95.16% (n= 177) and the GDP 86.61% (n=97), p= 0.0005. This was followed by an improved attachment level by the Specialist members 88.65% (n=164) which was higher than GDPs 49.73% (n=92), p=0.0005. Both Specialist members 67.04% (n=120) and GDP 60.91% (n=67) had similar opinions regarding the radiographic support improvement, p=0.361. Microbial testing was the least parameter considered for treatment success in antimicrobial treatment (Specialist 10.34%, GDP 7.84%, p=0.282) (Table 5).

Table 5. Parameter for judgment of treatment success with antimicrobials in the main study population of the GDPs and Specialists in the United Kingdom.

Item

Specialist Society/List

GDP

P value

Number+

(%)

Number+

(%)

Patient satisfied with result

109/178

61.24

80/107

74.77

0.001

Reduction in bleeding

169/184

91.85

100/113

88.50

0.054

Reduction in probing depth

177/186

95.16

97/112

86.61

0.0005

Improved attachment level

164/185

88.65

92/185

49.73

0.0005

Reduced tooth mobility

129/181

71.27

94/113

83.19

0.012

Improved radiographic bone support

120/179

67.04

67/110

60.91

0.361

Microbial testing

18/174

10.34

8/102

7.84

0.282

Further steps to be taken when antimicrobial therapy was judged to be unsuccessful

The most common steps taken by the GDP when an antimicrobial was judged to be unsuccessful were 1) referral 94.29% (n=99), p=0.0005, 2) extraction 91.18% (n=93), p=0.001, and 3) re root debridement 90% (n=90), p=0.922.  There were no differences in the number of Specialist members 57.14% (n=92) and the GDP 62.63% (n=62) who opted for re root debridement together with a systemic antimicrobial if the antimicrobial was judged to be unsuccessful, p=0.200 (Table 6).

Table 6. Further steps when antimicrobial therapy was judged to be unsuccessful in the main study population of the GDPs and Specialists in the United Kingdom.

Item

Specialist Society/List

GDP

P value

Number

(%)

Number

(%)

Referral

57/170

33.53

99/111

89.20

0.0005

Re root debridement

154/172

89.53

90/106

84.91

0.338

Re root debridement + local delivery antimicrobial

70/162

43.21

56/98

57.14

0.019

Re root debridement + systemic antimicrobial

92/164

56.10

62/105

59.04

0.103

Periodontal surgery

165/182

90.66

56/106

52.83

0.0005

Maintenance

152/175

86.86

80/101

79.21

0.005

Extraction

153/176

86.93

93/108

86.11

0.0005

Associations between variables

In the main study result section, the data analysis of the survey consisted of four parts which explored the frequency distribution of the study participants, demographic characteristics, periodontal management and the use of systemic and local antimicrobial.

  1. The mean age of the sample was 44.8 years (range 23-70) and in relation to the years of graduation, the mean was 21.04 years (range 1-48). Regarding the gender, 36.63% of the population was male. The Specialist members significantly consisted of mainly females 41.27% (n=78) whereas males were dominant in the GDP group 70.18%% (n=80) (p=0.046).
  2. In terms of root surface debridement performed for a quadrant, the majority of the Specialist population opted to spend more time on the procedure as compared to the GDP population (p=0.0005). Specialists would also be more incline to routinely administer local anaesthetics for RSD (88.77%).
  3. The Specialist population treated more aggressive periodontitis patients than their GDP counterparts 94.14% (n=177) and unresponsive sites 90.10% (n=164) (p=0.0005).
  4. Regarding the use of systemic antimicrobials, the Specialist population would be more frequent to use systemic antimicrobial to treat aggressive periodontitis (76.90% (n=143), p=0.003), and for unresponsive sites (33.16% (n=64) p=0.008, missing value 55). Regarding local antimicrobials, a small number of Specialist members 2.22% (n=4) and GDP 4.80% (n=5) opted to prescribe this antimicrobial therapy for gingivitis respectively (p=0.005).
  5. There was a significant lower number of the GDP population who prescribed antimicrobials in regenerative procedures 13.8% (n=14) or implant procedures 22.22% (n= 24) (p=0.0005).
  6. Regarding the perception of successful treatment with antimicrobials, the GDP 32.58% (n=29) population opted to report that local antimicrobial therapy was often/routinely/very successful.
  7. The Specialist population noted that it was easier (median 8) to decide to use systemic and local delivery antimicrobials in periodontal therapy (97.88% and 92.60% respectively, p=0.0005).
  8. The most common reason for using local antimicrobial was because of its effectiveness; e.g., more effective than RSD alone as reported by the GDP population (65.85%), and this was significantly different when compared to the Specialist population (51.16%), p=0.050. The most common reason for not using the type of antimicrobial was due to lack of supporting research data which was reported by the Specialist population (74.32%, p=0.001)
  9. Reduction in probing depth was judged to be the most frequent parameter for treatment success with antimicrobials by the Specialist population (95.16%, p= 0.0005). Microbial testing was not considered to be a major variable for the treatment success in antimicrobial treatment, however no differences were noted between the groups (Specialist 10.34%, GDP 7.84%, p=0.282).
  10. The most common steps taken by the GDP population when antimicrobials were judged to be unsuccessful was referral to a Specialist 89.20%, p=0.0005, whereas the Specialist was more inclined to perform periodontal surgery 90.66%, p=0.0005.

Discussion

One of the main observations from the present study related to the BSP members’ demographic characteristics was the difference in the mean years from graduation namely 21.04 years (range 1-48 years). Regarding Specialist membership, a larger number of Specialists were members of a Specialist society (85.56%), and 80% were BSP members. In the present study (in comparison with the previous results from Choudhury et al. [[8]), a significantly proportion of BSP/Specialist members indicated that they had attended a course or lecture on systemic (89.73% vs. 88.3%) or local delivery antimicrobial delivery (76.50% vs. 90.9%) in the treatment of periodontal disease. These figures also contrasted dramatically with the responses of GDPs from the present study where the attendance was significantly different to that of the Specialist colleagues. This observation would appear to support the conclusions by Palmer et al. [7] who reported that there were significant differences in the knowledge of the use of antibiotics from those practitioners who attended a postgraduate course. The response rate to the present study compared reasonably to the response rate from previous questionnaires studies [17-18]. The response rate for the questionnaires in the Choudhury et al. [8] was 73% which was higher than the response rate in the present study. There were however, sufficient data to compare the results from the two studies, although it should be noted that the periodontal categories used in the studies were different as the studies used a different classification system of periodontal disease. In retrospect it may have been useful to construct a simple algorithm to compare the results. A note of caution however should be noted in regard to the recruitment of the BSP members as there may be a degree of unconscious bias due to number of questionnaires handed out at a BSP meeting in Manchester by EAP (e.g., 91% rate from 100 questionnaires).

The present study noted that the use of systemic antibiotics by the participants generally were in accord with both previous and current recommendations [2, 12, 16, 19-20].  The BSP members prescribed a more frequent use of antibiotics when treating more complex cases compared to GDPs. This practice may be due in part to the referral habits of the general practitioners who would refer the more advanced cases to Specialists (as recommended, e.g., BSP guidelines [based on the Basic Periodontal Examination]). One of the problems which may occur when referring patients with an advanced problem to a Specialist it may force the specialist to take a more aggressive treatment approach then if the patient had been referred at an earlier stage of the disease process [4].

No significant differences were noted between BSP members/Specialists and GDPs in the use of an antimicrobial in the treatment of chronic periodontitis, although a relatively small number of participants prescribed an antibiotic for the treatment of gingivitis. Both groups however prescribed both systemic and local antibiotics/antimicrobials for the treatment of aggressive periodontitis and necrotising ulcerative gingivitis. BSP members/Specialists would on account of their higher frequency of treating aggressive periodontitis, routinely prescribe antibiotics/antimicrobials whereas necrotising ulcerative gingivitis was mainly treated by the GDPs. When comparing the results from the present study to the previous findings of Choudhury et al. [8] it was evident that BSP members/Specialists prescribed antimicrobials more frequently to treat aggressive periodontitis (76.90% vs. 52.7%) however the treatment of the unresponsive sites was lower in the present study (33.16% vs. 49.6%.). However, this apparent different may be as a result of the changes in the American Academy of Periodontology (AAP) classification rather than an actual change in the treatment of the conditions [16, 21]. A further observation between the two studies was that in the present study, in comparison to Choudhury et al. [8], the BSP Members/Specialists reported the limited use of antibiotics and antimicrobials in general. In the present study the BSP members/Specialists were more inclined to prescribe an antimicrobial for regenerative (45.60%) or implant therapy procedures (46.93%), although the frequency of prescription was relatively low.  According to Heitz-Mayfield [2] this may be as a result of the limited data available on this practice which may subsequently lead to a degree of uncertainty by practitioners. This observation may also be true when considering guidelines and protocols for antibiotic prescribing regimens in dental implants procedures [11]. Regarding the use of a local antimicrobial, the results from the present study contrasted with the study by Choudhury et al. [8]. In general, a higher number of GDPs prescribed local antimicrobials as compared to the BSP members/Specialists although this was not statistically significant. This may be due to the perception by the GDPs that local antimicrobial therapy was more successful in resolving periodontal problems than BSP members. One observation that may be a concern was the observation that a relatively small number of GDPs (4.80%) prescribed an antimicrobial for the treatment of gingivitis. There are several reasons for this, for example a misunderstanding of what the question was asking or a random mistake when completing the questionnaire. However, this may by supported by several investigators who reported that there are numerous prescriptions which were not in accord with the normal recommendations [5, 10].

One of the problems that was apparent from the results from the present study was that of decision making in the prescription and use of antibiotics/antimicrobials for the treatment of periodontal disease. This may be due to a number of reasons, for example the lack of understanding or confidence in the evidence of the efficacy of a particular drug, in comparison to the Choudhury et al. [8] study where some of the antimicrobials were relatively new to the market GDPs were more willing to prescribe and use antimicrobials as a result of their ease of use. It was also apparent as indicated previously that the general perception of GDP’s was that the use of a local antimicrobial in treating periodontal disease would be successful. Furthermore, a higher number of GDPs choose to use a local antimicrobial as they considered it to be more effective than root surface debridement alone, and more cost effective than the other options in the questionnaire. Other reasons provided by the GDPs was that the use of a local antibiotic/antimicrobial would avoid the need for additional surgical procedure and that the patient often requested the treatment as well as indicating that patients were generally satisfied with the treatment. Regarding the reasons for not using a local antimicrobial, cost would appear to a barrier for the GDPs, however the lack of postgraduate training locally was also a major factor, which was similar to the previous study by Choudhury et al. [8] (64.56% vs. 47.6%). This was not surprising as it was evident from the significantly less numbers of GDPs who reported attending a lecture or course on local antimicrobial compared to BSP members/Specialists. The importance of updated one’s knowledge on this topic may therefore be a factor in the decision-making process as to whether to use or not use antibiotics/antimicrobials. There was however a strange anomaly in the responses from the GDPs in that they noted that one of the reasons for not prescribing an antibiotic as the lack of supporting research data in the literature. In comparison to GDPs, the BSP members/Specialists reported that they spent more than 30 minutes for debridement under local anaesthetic as compared to the GDPs. This would suggest that mechanical treatment performed by the specialist may be more effective than that of the GDPs who may spend less time due to the constraint of the NHS service provision.  A small percentage of the both specialist and GDPs in the present study reported that medico legal issues where a concern when considered whether to use/not use an antibiotic/antimicrobial. This would appear to be supported by the results of a questionnaire study by Lockhart et al. [22] who investigated the opinions and practices of infectious disease consultants regarding antimicrobial prophylaxis in dental procedures. 24% of the consultant population replied that the medico legal decision played a greater role than clinical data in the decision-making process.

When considering the success of an antimicrobial in the treatment of periodontal disease, both groups of participants indicated that the use of microbial testing was the least desirable variable to be taken into account when making a judgement, This observation was less than that reported in the Choudhury et al. [8] study (10.34% vs. 83.3%). When considering which of the clinical parameters were routinely used in their practice. BSP members/Specialists reported significantly higher numbers of these variables, for example in reduction in bleeding level, reduction in probing depth, improved attachment level, and improved in radiographic bone support. It is therefore evident from the results of the present study that while both GDPs and BSP/Specialist members followed the current recommendations when prescribing and using systemic and local antimicrobial in periodontal therapy there is still a requirement for practitioners to be aware of more recent and updated universally accepted protocols and guidelines on the appropriate prescription and use of antibiotics/antimicrobials.

Conclusion

The results of the present study would indicate that there were limitations in both, the awareness, knowledge and prescription by dentists in the use of antibiotics/antimicrobials in the treatment of periodontal disease. Furthermore, there does not appear to be consistency in prescribing in terms of antibiotics/antimicrobials, dose or duration in root surface debridement, regenerative and implant procedures. In conclusion there is therefore a need for dentists to follow current guidelines when prescribing antibiotics/antimicrobials in order to avoid unnecessary prescriptions, antibiotic resistance and adverse drug reactions.

References

  1. Preshaw PM (2004) Antibiotics in the treatment of periodontitis. Dent Update 31: 448–450, 453–4, 456. [crossref]
  2. Heitz-Mayfield LJ (2009) Systemic antibiotics in periodontal therapy. Aust Dent J 54: 96–101.
  3. Herrera D, Matesanz P, Bascones-Martínez A, Sanz M (2012) Local and systemic antimicrobial therapy in periodontics. J Evid Based Dent Pract 12: 50–60. [crossref]
  4. Preus HR, Albandar JM, Gjermo P (1992) Antibiotic prescribing practices among Norwegian dentists. Scand J Dent Res 100: 232–235. [crossref]
  5. Palmer NO, Martin MV Pealing R; Ireland RS (2000) An Analysis of Antibiotic Prescriptions From General Dental Practitioners In England. J Antimicrob Chemother 46: 1033–1035.
  6. Palmer NO, Martin MV, Pealing R, Ireland RS (2001) Paediatric antibiotic prescribing by general dental practitioners in England. Int J Paediatr Dent 11: 242–248. [crossref]
  7. Palmer NO, Martin MV Pealing R; Ireland RS, Roy K, Smith A; Bagg J (2001) Antibiotic Prescribing Knowledge of National Health Service General Dental Practitioners in England And Scotland. J Antimicrob Chemother 47: 233–237.
  8. Choudhury M, Needleman I, Gillam D; Moles DR (2001) Systemic and local antimicrobial use in periodontal therapy in England and Wales. J Clin Periodontol 28: 833–839.
  9. Mainjot A, D’Hoore W, Vanheusden A, Van Nieuwenhuysen JP (2009) Antibiotic prescribing in dental practice in Belgium. Int Endod J 42: 1112–1117. [crossref]
  10. Dar-Odeh NS, Abu-Hammad OA, Al-Omiri MK, Khraisat AS, Shehabi AA (2010) Antibiotic prescribing practices by dentists: a review. Ther Clin Risk Manag 6: 301–306. [crossref]
  11. Ireland RS, Palmer NO, Lindenmeyer A, Mills N (2012) An investigation of antibiotic prophylaxis in implant practice in the UK. Br Dent J 213: 14. [crossref]
  12. Gillam DG; Turner W (2014) Antibiotics In The Treatment of Periodontal Disease: A Guide For The General Dental Practitioner. Prim Dent J 3: 43–47.
  13. SDCEP Scottish Drug Prescribing for Dentistry Dental Clinical Guidance 3rd Edition Update June 2017. http://www.sdcep.org.uk/wp-content/uploads/2017/06/SDCEP-Drug-Prescribing-Ed-3-Update-June-2017.pdf
  14. Public Health England Dental antimicrobial stewardship: toolkit. Resources to help primary care practitioners promote the appropriate use of antibiotics in dental care. Published 9th November 2016; Updated 16th July 2019. https://www.gov.uk/guidance/dental-antimicrobial-stewardship-toolkit.
  15. Armitage GC (1999) Development of a classification system for periodontal diseases and conditions. Ann Periodontol 4: 1–6. [crossref]
  16. Armitage GC (2004) Periodontal diagnoses and classification of periodontal diseases. Periodontol 2000 34: 9-21. [crossref]
  17. Gillam DG, Seo HS, Bulman JS; Newman HN (1999) Perceptions of dentine hypersensitivity in a general practice population. J Oral Rehabil 26: 710–714.
  18. Gillam DG, Seo HS, Newman HN; Bulman JS (2001) Comparison of dentine hypersensitivity in selected occidental and oriental populations. J Oral Rehabil 28: 20–25.
  19. Palmer NA (2003) Revisiting the role of dentists in prescribing antibiotics. Dent Update 30: 570–574. [crossref]
  20. Dumitrescu AL (2011) Chapter 3 The Systematic Use of Antibiotics in Periodontal Therapy. In Antibiotics and Antiseptics in Periodontal Therapy. Ed Dumitrescu AL. Springer-Verlag Berlin Heidelberg 2011 Pg No: 79–169.
  21. Wiebe CB, Putnins EE (2000) The periodontal disease classification system of the American Academy of Periodontology–an update. J Can Dent Assoc 66: 594–597. [crossref]
  22. Lockhart PB, Brennan MT, Fox PC, Norton HJ, Jernigan DB, Strausbaugh LJ (2002) Decision-making on the use of antimicrobial prophylaxis for dental procedures: a survey of infectious disease consultants and review. Clin Infect Dis 34: 1621–1626.

An In Vitro Comparison of A Novel Self-Assembling Peptide Matrix Gel and Selected Desensitizing Toothpastes in Reducing Fluid Flow by Dentine Tubular Occlusion

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DOI: 10.31038/JDMR.2020311

Abstract

Objectives: The objective of this explorative in vitro study was to evaluate the ability of a novel self-assembling peptide matrix gel with calcium phosphate in effectively occluding dentine tubules compared to selected desensitizing toothpastes.

Methods: Mid-coronal dentine discs with a thickness of 1 mm were sectioned from caries-free human molars. The discs were etched with 6% citric acid for 2 minutes, halved and subjected to a 2-minute brushing with a novel gel (SAPM) and three selected desensitizing toothpastes ([SRP], [SRR] and [CSP]). The ability of the desensitizing gel and toothpastes to occlude the dentine tubules was assessed and compared before and after brushing using Scanning Electron Microscopy (SEM) on both etched and fractured dentine surfaces. The SEM observations were supplemented by hydraulic conductance measurements using a modified Pashley model before and after tooth brushing (n=5).

Results: The results demonstrated that there was a reduction in both the number and the diameter of the open dentine tubules, which was evident for all the treated dentine discs. The particles that occluded the open dentine tubules, however had different morphologies and distribution. The self-assembling peptide matrix gel (SAPM) demonstrated greater reduction in the number of open tubules compared to the other desensitizing toothpastes. Reductions in the hydraulic conductance measurements were observed for all tested materials (mean [SD, %]: SAPM 55.1 [12.5], SRP 64.9 [18.5], SRR 39.1 [17.1] and CSP 27.6 [6.8]). No statistically differences were observed between the SAPM and SRP, SRR toothpastes (paired t-Test; ≤0.05) although a significant difference was noted between the SAPM and the CSP toothpaste. There was an overall trend for reduction for the SAPM compared to the SRR toothpaste.

Conclusion: The results would suggest that a novel self-assembling peptide matrix gel (SAPM) was effective in blocking the dentine tubules and may therefore have the potential to be an effective desensitizing product for the treatment of Dentine Hypersensitivity.

Keywords

Self-assembling Peptide Matrix, Desensitizing Toothpastes, Tubular Occlusion, Hydraulic Conductance

Introduction

According to Hill & Gillam [1] Dentine Hypersensitivity (DH) is a clinical problem that may have impact on the Quality of Life of individuals who experience discomfort when eating and drinking hot and cold food during their day to day activities. The condition is postulated in the Hydrodynamic Theory [2] to be a result of minute fluid shifts within the dentine tubules following an external stimulus (e.g., cold, heat etc.). Currently toothpastes, gels and mouthwashes are designed to reduce or relieve pain arising from DH based on either their 1) tubular occluding components (e.g., silica, calcium carbonate, hydroxy- or nano-hydroxy apatite(s), oxalates or bioactive glass) or 2) nerve desensitization properties (e.g., potassium ions). Most of today’s commercial products have been reformulated from well-established technologies [3–5]. One of the few new developments representing a biomimetic approach to remineralization and thus being an alternative to the traditional desensitizing products for treating DH, is a self-assembling peptide matrix (SAPM) gel. The biomimetic self-assembling peptide P11–4 (SAP P11–4) has been shown to be effective as a non-invasive treatment for early stage dental caries [6–12]. In the treatment of early caries SAP P11–4 has been shown to diffuse into the subsurface micro-pores of enamel and form a 3D scaffold/matrix/hydrogel thereby mimicking the enamel matrix original function during tooth development, to support apatite crystallization, thus reversing tooth decay [6, 8]. According to previous reports SAP P11–4 (Ace-Gln-Gln-Arg-Phe-Glu-Trp-Glu-Phe-Glu-Gln-Gln-NH2) self-assembles into a matrix or hydrogel [13] under defined conditions. This matrix can support biomimetic mineralization and enamel regeneration [9]. The glutamic acid residues on the surface have been shown to act as nucleation sites for apatite formation and result in remineralisation of the lesion body [14].

The first product based on SAPM for treatment of Dentine Hypersensitivity (DH) has been marketed (Curodont D’Senz, Credentis ag, Switzerland). It has been recently shown to be effective in reducing DH in a randomised clinical study by Schlee et al. [15], demonstrating faster desensitization than a toothpaste including 5% Arginine and Calcium Carbonate. This product uses the same self-assembling peptide as included in the product for remineralization of carious lesions but was formulated as a gel with the self-assembling peptide in its assembled (i.e. matrix, SAPM) state. The SAPM is able to form a film on the dentine surface, without undergoing any chemical or physical transformation, solely by binding to the available Calcium ions on the tooth surface [14].

The in vitro measurement of fluid flow (hydraulic conductance [Lp]) in the dentine disk model has been used to assess the ability of desensitizing agents in treating Dentine Hypersensitivity (DH) [16]. According to Bränström [2] the mechanism underpinning the hydrodynamic theory is associated with rapid minute shifts in dentine fluid flow within the open dentine tubules, which acts as a capillary bore when a stimulus (e.g., cold) is applied to an exposed dentine surface. Fluid flow is dependent on the fourth power of the radius and therefore, any reduction in the diameter of the dentine tubule lumen should in theory reduce the fluid flow within the tubule, which in turn will decrease DH [16]. These investigators used a dentine section of approximately 1.0 mm in thickness to measure the hydraulic conductance of each desensitizing product applied on a dentine disc according to Greenhill & Pashley [16]. The aim of this explorative in vitro study was to investigate the ability of a commercially available SAPM containing gel in occluding dentinal tubules and thus reducing hydraulic conductance (fluid flow) through dentine.

Objectives

The main objective of this explorative in vitro study was to access the ability of a novel SAPM gel in reducing fluid flow (hydraulic conductance [Lp]) by tubular occlusion and to compare the effectiveness of the SAPM to three desensitizing technologies incorporated into toothpastes with established tubular occluding properties e.g., Colgate Sensitive ProRelief [CSP], Sensodyne Repair and Protect [SRP], and Sensodyne Rapid Relief [SRR].

Methods: In the present experiments a mid coronal dentine disc was used in a modified Pashley cell (Figure 1) [10, 17]. The fluid flow through the dentine discs was measured for the SAPM Gel and three selected desensitizing toothpastes (Table 1). The non-treated dentine discs were used as a control to the measurements obtained from the treated dentine discs.

JDMR 2020-302_David Gillam_F1

Figure 1: Dentine Disc Preparation (Based on Mordan et al., [17]).

Table 1. The desensitizing toothpastes investigated in the study.

Toothpaste Investigated

Company

Principal Ingredients

Self-Assembling Peptide Matrix Gel (Curodont D’Senz)(SAPM)

Credentis AG

P11–4

Colgate Sensitive ProRelief (CSP)

Colgate Palmolive

Pro-Argin(5% Arginine) Calcium Carbonate

Sensodyne Repair and Protect (SRP)

GSK Consumer Healthcare

Calcium phosphosilicate (Novamin) Bioactive Glass

Sensodyne Rapid Relief (SRR)

GSK Consumer Healthcare

Strontium Acetate*

*Current formulations include Stannous Fluoride instead of Strontium Acetate

Dentine Disc preparation: Caries free extracted mandibular and maxillary molars were used for the study. Teeth were obtained from the tooth bank at the Royal London Dental Hospital under agreed Ethics Committee approval (QMREC 2011/99). Teeth were stored in a 70/30 ethanol/water solution within the Department of Dental Physical Sciences under the Human Tissue Act (2004) regulations prior to the evaluation of the selected products.

The criteria for the teeth selection were as follows:

  1. Molar teeth.
  2. Large molar teeth, with a dentine area of at least 6 mm in diameter.
  3. Carious free.

The selected teeth were cleaned and stored in a 3% sodium hypochlorite solution (prepared from 14% sodium hypochlorite solution after dilution) for 24 hours to allow for disinfection. After the disinfection procedure, the teeth were stored in 70/30 ethanol/water prior to use. Each tooth was fixed in a sample holder using impression material compound (Kerr, Model: 813–00425) and placed perpendicular to the annular diamond coated blade of a precision slicer (Microslice II, Malvern Instruments, UK). The crown of the tooth was discarded, and the cutting continued below the dentine-enamel junction to produce discs consisting of mid coronal dentine (Figure 1). The diamond blade was adjusted to result in discs with a thickness of 1 mm. The prepared discs were then stored in 70/30 ethanol/water.

Polishing, Cleaning and Etching of Dentine Discs

Prior to the assembling of the dentine discs into the Pashley permeability holder (cell), they were polished, cleaned and etched. The polishing step was completed by wet polishing both sides of the dentine discs against a series of silicon carbide grinding paper (P800 – P4000 equivalent to 5 µm) using a polishing machine (Kent 4 Automatic Lapping & Polishing Unit, Kemet International Ltd., UK). The thickness of the polished dentine disc was measured using a digital Vernier calliper (AK962EV, Sealey). The polished dentine discs were cleaned (2x5min) in an Ultrasonic bath (Kerry Ultrasonic bath), the water was changed after the first five minutes.

Dentine Tubule Occlusion Evaluation by Scanning Electron microscopy (SEM)

The dentine discs were etched (6% citric acid; 2 min) and rinsed thoroughly with de-ionised water. Each test surface was marked and then fractured into two halves using dental pliers, one half was used as a control, and the other half was subjected to two minutes brushing with 0.1 ml toothpaste by an electrical toothbrush with a sensitive brush head (Oral-B Trizone 5000, UK). Following brushing, the discs were rinsed by water and dried in air. All four test products described in Table 1 were evaluated and new brush heads were used for each of the test toothpastes.The control-half dentine disc and the test-half treated were again halved into quarter discs. A quarter from each half was prepared for SEM analysis. The specimens were gold coated and viewed under a field emission scanning electron microscope (FEI Inspect F, Oxford Instruments, Oxfordshire, UK) in the secondary scanning imaging mode at a voltage of 10 KV and a working distant of 10 mm. The deposit on the surface of the dentine and the distribution of the particles around and within the dentine tubules was investigated. SEM images were taken at the same region (close to the centre of the dentine disc) of the control and treated dentine disc with same magnification(s) (2000x, x 5000x, 10,000x and 20,000x) to evaluate the effectiveness of the ability of each toothpaste in occluding the dentine tubules. A cross section of a dentine disc was prepared by cutting one dentine disc in half using dental pliers [17]. The section designated the ‘test’ half was treated by applying the SAPM according to the Manufacturer’s instructions and viewed under the SEM.

Permeability Measurement (Hydraulic Conductance [Lp])

Following cleaning, the etched dentine disc was then placed in the Pashley specimen holder and prepared for the measurement of dentine permeability (hydraulic conductance). An air bubble (0.1 ml gas) was introduced into the system via a disposable plastic syringe, which then passed through the tubing and traversed the micro-capillary set up. The distance (in cm) that the air bubble travelled in the micro-capillary was recorded in one min intervals. Overall a continuous 10 min measurement was performed. The distance that the air bubble travelled was plotted against time, where a linear correlation was expected. The slope of the linear relationship was the fluid flow rate for the acid etched dentine disc. Following the application of the test products (see above) the toothpaste residual was rinsed with de-ionised water for five seconds and the fluid flow measurements were repeated in the same manner as described previously. The percentage reduction of the fluid flow was calculated using the following equation and presented in percentage (%).

JDMR 2020-302_David Gillam_F10

The selected desensitizing toothpastes investigated in the present study are listed in Table 1. 20 dentine discs were used for the permeability aspect of the study. Five discs were used in each of the four toothpaste groups.

Results

Figure 2–7 show the SEM images of the dentine discs 1) control (un-brushed sections) and 2) after brushing with the tested toothpastes at 3 different magnifications (2000x, 5000x and 20,000x) and a 3) cross-sectional view of the dentinal tubuli (Figure 2-3 only for SAPM). A magnification of 2000x gives an overall impression of the dentine tubules occlusion, where high magnification shows how the particles were distributed in and around the dentine tubules. The dentine disc treated with SAPM showed almost complete dentine tubule coverage by placing a hydrogel film over the dentine surface. The dentine disc surface was rather smooth with some big clusters presumably Dicalcium Phosphate particles from the formulation (Figure 2–4).

SEM images of dentine tubules treated SAPM before (left) and after treatment (right) can also be observed in Figure 4.

JDMR 2020-302_David Gillam_F2

Figures 2–3: Showing the hydrogel film of the SAPM gel covering the dentine surface: Figure 2 shows the top down view whilst Figure 3 shows the cross-section. The presence of large clusters was also observed which may be result of the deposition of dicalcium phosphate particles from the formulation.

JDMR 2020-302_David Gillam_F3

Figure 4: SEM images of dentine tubules treated with self-assembling peptide matrix (SAPM) before treatment (left) and after treatment (right).

CSP treated dentine discs showed levels of dentine tubule occlusion and a different morphology of the elongated particle, which has a tendency of forming clusters was observed (Figure 5). The dentine discs treated with SRP (Figure 6) provided levels of occlusion, however, a large area of open dentine tubules was observed. A small amount of fine particles (submicron level) was also observed on the dentine surface. Large clusters of particles also occluded some of the tubules. In contrast, the specimens treated with SRR formulation (Figure 7) provided better coverage compared with the SRP formulation (Figure 6). It was clear that there was precipitation of particles within the dentinal tubules as well as on the dentine surface.

JDMR 2020-302_David Gillam_F4

Figure 5: SEM images of dentine tubules treated with Colgate Sensitive ProRelief Toothpaste, before treatment (left) and after treatment (right).

JDMR 2020-302_David Gillam_F5

Figure 6: SEM images of dentine tubules treated with Sensodyne Repair and Protect Toothpaste, before treatment (left) and after treatment (right).

JDMR 2020-302_David Gillam_F6

Figure 7: SEM images of dentine tubules treated with Sensodyne Rapid Relief Toothpaste, before treatment (left) and after treatment (right).

Figure 8 demonstrated the variation of the fluid flow reduction (FFR) of the five discs used following the application of SAPM Gel (39.4%-65.7%). The mean FFR for the SAPM Gel was 55.1% which compared favourably to the other desensitizing products (Table 2). The percentage of fluid flow reduction by the SAPM Gel was statistically higher than for CSP, however no significantly differences were observed between the SAPM Gel and both SRP and SRR (paired t-test).

JDMR 2020-302_David Gillam_F7

JDMR 2020-302_David Gillam_F8

JDMR 2020-302_David Gillam_F9

Figure 8: Plot showing the fluid low changes of the dentine discs after 2 min brushing with the SAPM Gels (discs 1-5), where blue diamond represents etched control, and red square for after treatment (Fluid Flow Reduction [FFR] range: 39.4%-65.7%).

Table 2. Fluid Flow Reduction for the tested toothpastes (n=5).

Toothpaste

Mean FFR (%)

SD (%)

SAPM Gel

55.1a

12.5

CSP

27.6b

6.8

SRP

64.9ac

18.5

SRR

39.1ab

17.1

Discussion

According to Hill and Gillam [1] despite the vast array of commercial products designed either as professionally applied products or techniques (Dentist applied) or as over-the counter products (OTC) (Home use) there is no universally accepted product that can completely resolve DH. The desensitising technologies evaluated in the current in vitro study included a novel self-assembling peptide matrix (SAPM) gel and three selected desensitizing toothpastes with established tubular occluding properties namely 1) a technology consisting of arginine, a naturally occurring amino acid, and an insoluble calcium compound, in the form of calcium carbonate  (CSP), 2) a 45S5 bioactive glass formulation (SRP) and 3) a strontium acetate formulation (SRR). The use of SAP P11–4 as a non-invasive regenerative treatment for early stage dental caries has been documented [3–12]. Recent reports on favourable remineralisation after SAPM application have been published [18–19]. A randomised clinical trial investigating an SAPM Gel (as investigated in this report) demonstrated fast relief of DH compared to CSP [15]. An in vitro study by João-Souza et al. [20] also compared the desensitizing effects of selected toothpastes including a diluted SAPM formulation under erosive conditions. The other three test products of the present study (CSP, SRP, and SRR) have also been documented as effective desensitizing toothpastes based on both in vitro and in vivo evidence [3–4, 21–27].

The in vitro evaluation of desensitizing products was undertaken using the established methodology described by Greenhill & Pashley [16] and Mordan et al. [17], although one of the limitations using dentine discs from different teeth is the variability between and within the discs particularly when investigating hydraulic conductance (see variability with the fluid low within the five discs). This is due in part to the variation of the regional flow which may be affected by the proximity of the dentine disk to the pulp [27–29]. Other limitations of using this particular model relate to 1) the effect of the storage medium and the etching agents such as a sodium hypochlorite solution and citric acid which may impact and modify the dentine surface as well as the collagen; 2) the unknown age and history of the teeth and 3) the thickness, location and orientation of the dentinal tubules which may have an impact on any of the results from studies of this nature [30–34]. It should be noted, however that one of the original objectives of using the dentine disc was to identify the mode of action of the desensitizing agents as well as their potential as a therapeutic formulated product to treat DH [17].

All the treated discs in the present study resulted in a reduction in the number and the size of open dentine tubules on the surface of the dentine disc. This would suggest that there was a degree of effective tubular occlusion within all groups. The particles that occluded the open dentine tubules, however had different morphologies and distribution across the disc surface. The SAPM gel demonstrated the highest tubuli occlusion compared to the other groups, based on the SEM analysis. The SEMs of the treated discs suggested that the tubule occlusion originated by the placement of a hydrogel film of SAPM on the tooth surface. Yet, it is important to supplement the evidence from the SEM data by relating it to the hydraulic conductance measurements, as this new type of surface occlusion might result in a different degree of fluid flow inhibition as seen by insoluble particles from the conventional desensitisation groups. It is also important to recognise that the occlusion by the SAPM gel, does not involve any chemical or physical reaction, whereas all the other products rely on a precipitation reaction within the dentinal tubuli. For example, according to several investigators, arginine in the CSP formulation has been postulated to form a calcium arginine complex with calcium carbonate on the tooth surface and within the dentine tubules [1, 4]. The chemistry of this process however is poorly understood and has not been characterized in any detail [1]. The 45S5 bioactive glass composition in the SRP formulation was originally designed as a bone substitute and not as an additive in toothpastes for treating DH. It has been postulated that the glass particles dissolve in the mouth releasing Ca2+ and PO43- ions forming a hydroxycarbonated apatite (HCA) on the tooth surface and as such may not be acid resistant for permanent tubuli occlusion [1]. The main mode of action of strontium acetate (and strontium chloride) (SRR) for treatment of DH, has been suggested to be by tubular occlusion although the actual effect attributed to strontium in clinical studies has yet to be defined [35, 36]. Current formulations of SRR have replaced Strontium Acetate with Stannous Fluoride.

Most of the toothpastes evaluated in the present in vitro study exhibited very good tubule occlusion and fluid flow inhibition following tooth brushing, the exception being SRP that was less effective in occluding the dentinal tubules (Figs 4–8, Table 2). One possible reason for this observation was that in the mouth this toothpaste reacts with saliva to form hydroxyapatite and as such may perform more effectively in the clinical environment rather than in the in vitro setting, as has been shown in clinical trials [23, 25].The reductions in the dentine hydraulic conductance measurements were observed for all tested materials (mean [SD, %]: SAPM 55.1 [12.5], SRP 64.9 [18.5], SRR 39.1 [17.1] and CSP 27.6 [6.8]). No statistically differences were observed between the SAPM and SRP, SRR toothpastes (paired t-Test; ≤0.05) – possibly due to the small sample size in this explorative study – although a significant difference was noted between the SAPM and the CSP toothpastes. There was an overall trend for reduction for the SAPM compared to the SRR toothpaste.

Although the SAPM gel was effective in the present study compared to the other tested products there is currently only one report of a randomised clinical trial comparing its clinical efficacy to that of the CSP product [15]. An additional in vitro study has evaluated a SAPM containing product in a daily erosion toothpaste (with a much lower concentration of SAPM) [20], where the investigators reported that none of the desensitizing products showed any significant effects on tubular occlusion under the erosive conditions used. There are, however, significant differences in the methodology used in this study [20] compared to the current study. For example, the specimens were submitted to a 5-day erosion-abrasion cycling model and the fluid flow reductions were not shown as a time dependent graph, but rather as a value (with uncommonly large error bars). Furthermore, the toothpaste used in the João-Souza et al. study [20] included SAP P11–4 at a significantly lower level (1/30) than the product investigated in the current study. It would therefore be of interest to compare these two SAPM containing products in a future study to determine their individual effects on tubular occlusion and identify the optimal concentration and application frequency for SAPM.

Conclusion

The results from the current explorative in vitro study would suggest that a novel self-assembling peptide matrix gel was effective in occluding the dentine tubules and may therefore have the potential to be an effective desensitizing product for the treatment of dentine hypersensitivity.

Acknowledgement

The research was funded by Credentis AG, Switzerland. The work of Hawshan Abdulrahman Mustafa was supported by the Kurdistan Regional Government- Human Capacity Development Program (KRG-HCDP).

References

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  6. Kirkham J, Firth A, Vernals D, Boden N, Robinson C, Shore RC, et al. (2007) Self-assembling peptide scaffolds promote enamel remineralisation. J Dent Res 86: 426–430. [Crossref]
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  10. Chen X, Gillam DG, Lysek DA, Hill RG (2014) In Vitro Evaluation of Dentine Remineralisation by a Self-Assembling Peptide Using Scanning Electron Microscopy. 61th ORCA Congress July 2–5, Greifswald, Germany, Abstract no. 40.
  11. Schlee M, Schad T, Koch JH, Cattin PC, Rathe F (2018) Clinical performance of self-assembling peptide P11–4 in the treatment of initial proximal carious lesions: A practice-based case series. J Invest Clin Dent.
  12. Bröseler F, Tietmann C, Bommer C, Drechsel T, Heinzel-Gutenbrunner M, Jepsen S (2019) Randomised clinical trial investigating self-assembling peptide P11–4 in the treatment of early caries. Clin Oral Investig 2019 Apr 29. [Epub ahead of print].
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  14. Saha S, Yang XB Wijayathunga, N Harris, S Feichtinger, GA Davies, et al. (2019) A biomimetic self-assembling peptide promotes bone regeneration in vivo: A rat cranial defect study. Bone 127: 602–611.
  15.  Schlee M, Rathe F, Bommer C, Bröseler F, et al. (2018) Self-assembling peptide matrix for treatment of dentin hypersensitivity: A randomized controlled clinical trial. J Periodontol 89: 653–660. [Crossref]
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  18. Soares R, de Ataide IDN, Fernandes M, Lambor R (2017) Assessment of Enamel Remineralisation with different Remineralising Agents. Journal of Clinical and Diagnostic Research 11: ZC136-ZC141.
  19.  Jablonski-Momeni A, Korbmacher-Steiner H, Heinzel-Gutenbrunner M, Jablonski B, Jaquet W, et al. (2019) Randomised in situ clinical trial investigating self-assembling peptide matrix P11–4 in the prevention of artificial caries lesions. Sci Rep 9: 269. [Crossref]
  20. João-Souzaa SH, Scaramuccia T, Borges AB, Lussic A, Carvalhoc TS, Aranhaa ACC (2019) Influence of desensitizing and anti-erosive toothpastes on dentine permeability: An in vitro study. J Dent (in press) 89: 103176. [Crossref]
  21. Sharif M, Iram S, Brunton P (2013) Effectiveness of arginine containing toothpastes in treating dentine hypersensitivity: A systematic Review. J Dent 41: 483–492. [Crossref]
  22. Yan B, Yi J, Li Y, Chen Y, Shi Z (2013) Arginine-containing toothpastes for dentin hypersensitivity: systematic review and meta-analysis. Quintessence International 44: 709–723. [Crossref]
  23. Ramamoorthi S, Nivedhitha MS (2013) Effectiveness of Bioactive glass Containing Dentifrice on Dentin Hypersensitivity – A Systematic Review. JPR:BioMedRx: An International Journal 1: 803–809.
  24. Karim BFA, Gillam DG (2013) The Efficacy of Strontium and Potassium Toothpastes in Treating Dentine Hypersensitivity: A Systematic Review. Int J Dent.
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  26. Gillam DG (2014) Treatment Approaches for Dentin Hypersensitivity. In Chapter 5 Clinician’s Guide to the Diagnosis and Management of Tooth Sensitivity S. Taha, B.H. Clarkson (eds.), DOI 10.1007/978-3-642-45164-5_5, © Springer-Verlag Berlin Heidelberg, Pg No: 51–79.
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Biosynthesis of Zinc oxide nanoparticles using Leptadenia hastata leaf extracts and their potential as antimicrobial agents

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DOI: 10.31038/JMG.2020311

Abstract

The Aim of this study is to focus at the evaluation of the potential of the antimicrobial activity of the synthesized Zinc chloride nanoparticles using Leptadenia hastata leaf extracts on selected bacterial; Escherichia coli (Gram–ve), Staphylococcus aureus, Gram +ve), Klebsielia Pneumonia (Gram +ve). The synthesized zinc oxide (ZnO) nanoparticles were characterized using UV, SEM and FTIR. The particles were further subjected to evaluation of their antimicrobial activity. The FTIR studies was observed to have shown the several chemical functional groups, while the SEM results showed the synthesized nanoparticles were in the range below 100 nm and the shape of the particles was slightly ellipsoidal as well as spherical. From the result it was observed that the synthesised nanoparticles have showed significant antibacterial activity against the gram-ve and gram +ve bacteria’s (Escherichia coli, Staphylococcus aureus and Klebsielia Pneumonia. This study being the first using Leptadenia hastata leaf extract should provide a new agent toward the fight of resistance bacterial and effective therapies in the field of medicine.

Keywords

Biosynthesis, Zinc oxide, nanoparticles, Leptadenia hastata, leaf, antimicrobial, characterization

Introduction

Green synthesis has been considered as another remedy in the field of medicine. Aside toxic chemical and physical method, biological method is considered use of medicinal plants extract for synthesis of nanoparticles. The surface and fraction of the atoms are responsible for the activity of the nanoparticles. This invention of green nanotechnology is considered eco-friendly and cost effective when compared to the others. The technology utilizes proteins as natural capping agents and its synthesis from plants utilize various secondary metabolites, enzymes, proteins and or other reducing agents which makes it suitable to use in various biomedical and clinical applications [1]. The advantage of using ZnO nanoparticles is that they have a strong potential against the pathogenic microbes when used in small concentration [2]. It was also reported that ZnO demonstrates significant growth inhibition of a broad spectrum of bacteria [3]. Thus, impaired wound healing in ulcer patients is a major complication. The elevated infections by bacterial such as Helicobacter pylori and many more resistant bacterial may interfere in the proper healing process. If left untreated will lead to delay in the healing process, as such introducing nanoparticle is an answer to such disturbing ailment. Many antibacterial agents have limitations in the clinical applications, because of complications and resistance towards pathogenic microorganisms. [4,5]. It was reported in some cases where few metal nanoparticles are known to have potential antimicrobial and consequential wound rejuvenating activity, but they also have some disadvantages related to the toxicity level [6].

This prompted the synthesize of nanoparticles by bio-assisted pathway to reduce their toxicity effect and provide better duodenal or stomach ulcer healing therapy to avoid and treat the resistance related pathogens. Thus, this study may provide a remedy with the green synthesis nanoparticles and its high potential towards antibacterial activity to control the resistance effect of Helicobacter phylori as well as other ulcer causing bacteria. Since this area is less explored, there is a need to consider the potential of this nanoparticles as to cutile the menace and the pain attached to this wound

Material and Method

Plant collection: The leafs of Leptadenia hastata (pers) Decne was collected in Michika local government in Adamawa state, Nigeria. It is a medicinally important plant. Fresh green leaves were harvested during the months of August to September.

Preparation of the plant extract: 5 g of fresh leaves were washed with distilled water and then cut, soaked in a 250 mL Erlenmeyer flask containing 100 mL of distilled water. The solution was boiled at 70 °C for 8 min. The leaf extract was allowed to cool to room temperature, filtered through Whatman number-1 filter paper, and the filtrate was stored for further experimental use.

Synthesis of ZnO Nanoparticles (NPs): 1 mM Zinc acetate [Zn (O 2CCH3)2 (H2O) 2] was dissolved in 50 ml distilled water and kept in stirrer for 1 hr, respectively as reported by [7]. Then 20 mL of NaOH solution was slowly added into the Zinc acetate solution and 25 mL of plant extract was added to the same. The colour of the reaction mixture was changed after 1 hr of incubation time. The solution was left in stirrer for 3 hrs. A light yellow colour was observed after the incubation time. This confirmed the synthesis of ZnO Nanoparticles (NPs). The precipitate was separated from the reaction solution by centrifugation at 8000 rpm at 60 °C for 15 min and pellet was collected from the filtered. The Pellet was dried using a hot air oven operating at 80 °C for 2 hrs and preserved in air-tight bottles for further studies.

Characterization of biosynthesized ZnO Nanoparticles (NPs): The Leptadenia hastata Optical properties of ZnO Nanoparticles (NPs) were characterized based on UV absorption spectra with the wavelength range of 300–500 nm. The FTIR characterization was obtained by taking 2 mg of ZnO Nanoparticle (NPs) and mixed with 200 mg of potassium bromide (FTIR grade) and pressed into a pellet for the characterization. The sample pellet was placed into the sample holder and FTIR spectra were recorded in FTIR spectroscopy at a resolution of 4 cm-1 [8]. The shape and size of the Nanoparticles were analysed by using SEM.

Antibacterial activity of synthesized ZnO Nanoparticles (NPs):

Preparation of Test Samples

The Leptadenia hastata zinc oxide (ZnO) nanoparticle from Leptadenia hastata leaf water extract was tested by disc diffusion method on nutrient agar medium as described by [9]. The extract exactly 5mg was dissolved homogeneity in 5mL of methanol giving a stock solution of 1000 μg/mL. Lower concentration of 10, 50, 100, 250, 500, and 1000ppm, i.e. six different volumes from the stock solution were taken for the studies.

Preparation of Bacteria Broth

The selected bacteria were used to evaluate the antibacterial activity of the Leptadenia hastata zinc oxide (ZnO) nanoparticle from Leptadenia hastata leaf water extract, Staphylococcus aureus, (+ve), Escherichia coli (–ve) and Klebsielia Pneumonia (+ve) were obtained from the stock culture provided by Virology Laboratory, Universiti Malaysia Sarawak. The nutrient broth was prepared according to manufacturer’s instruction, with 2.6 g of the dried broth dissolved in 200 mL distilled water followed by sterilization in autoclave at 121°C. The bacterial was sub-cultured in a 10 mL of broth, each in universal glass vail bottle for 16 hours inside an incubator equipped with shaker at 37°C [10]. After 16 hours’ incubation, turbidity (optical density/OD) of the bacterial broth was measured by using UV mini spectrophotometer (model 1240 of Shimadzu brand), comparable to that of nutrient broth standard tube for further use [11]. The measurement of the optical density was performed at wavelength 575nm and the bacterial broth was ready to be used when its turbidity was between OD 0.6 to 0.9. Nutrient broth was used to adjust the turbidity until the desired value was obtained.

Plate Inoculation

Inoculation of the bacteria was carried out in a biohazard cabinet and the procedure was based on method described by [12]. Approximately 1mL of the ready bacterial broth were transferred into mini centrifuge tubes. A sterile cotton swap was dipped into the mini centrifuge tube containing bacteria broth and streaked over entire of the agar plate surface, performed in four different directions. The agar plate was then left for 5–10 minutes before applying the test samples. The disc used was 6 mm diameter. A volume of 10μL of the test extract (Leptadenia hastata zinc oxide (ZnO) nanoparticle) of concentration 10, 50, 100, 250, 500 and 1000μg/mL were each pupated onto the discs and placed onto the agar plate by using sterile forceps and gently pressed to ensure contact. Next to be placed on the agar plate was the disc pupated with methanol as negative control, followed by 30μg of tetracycline as standard antibacterial agent (positive control). The plates were left at room temperature for 10 minutes to allow the diffusion of the test samples and the standards into the agar. Each of the test essential oil was tested in triplicate for the bacterium used. The plate samples were then incubated at 37°C for 24 hours before the inhibition zone around every sample disc being examined. The inhibition zone was measured in diameter (mm) to indicate the presence of antibacterial activity for each sample compared to the positive control.

Result and Discussion

Scanning Electron Microscope (SEM): SEM analysis is done to visualize shape and size of nanoparticle. JSM6510LV Scanning electron microscope was used to determine the shape of Leptadenia hastata capped ZnO NPs (Fig. 3). SEM images were seen in different magnification ranges which clearly demonstrated the presence of spherical shaped nanoparticle with mean average diameter of 70 nm [13].

JMG 304_Issac John Umaru_F3

Figure 3. SEM images of ZnO Nanoparticles (NPs) of Leptadenia hastata leaf in different magnification ranges

Fourier Transform Infra-Red Spectrometry (FTIR): Substance-specific vibrations of the molecules lead to the specific signals obtained by IR spectroscopy. FT-IR spectra and functional group involved in Leptadenia hastata ZnO Nanoparticle synthesis illustrated peak in the range of 1000–4000 cm −1 (Fig 4). Absorption band of ZnO Nanoparticle IR spectrum showed the presence of the functional group (O-H) which appeared at 3363.66 cm-1 bond. The IR spectrum (Figure 4) also shows an absorption band which indicated a C-H bond at 2970.49 cm-1 which suggested the presence of methyl carbon in the chemical structure. However, a double bond C=C stretching at 1772.35 cm-1 and 1566.86 cm-1 was also observed in the spectrum of ZnO Nanoparticle. The peak in the range of 1502.35 and 1409.81 corresponded to C=C stretch and in aromatic ring and C=O stretch in polyphenols and C–N stretch of Amide-I in protein. Weak peaks obtained at 1089.98 cm-1, 1010.10 cm-1 and 886.75 cm-1, 830.25 cm-1, 764.32 cm-1, demonstrated the presence of C-O stretching in amino acid, C-N stretching, C-F, C-l, C-Br strong stretching, and C-H bending respectively. A very ignorable peak obtained at 686.62 cm-1 demonstrated the probable presence of C- Alkyl chloride and Hexagonal phase ZnO thus supported by the report of [14].

JMG 304_Issac John Umaru_F4

Figure 4. FT-IR Spectrum of ZnO Nanoparticles (NPs) of Leptadenia hastata fresh leaf

JMG 304_Issac John Umaru_F1

Figure 1. Schematic representation of ZnO Nanoparticles (NPs) synthesis.

JMG 304_Issac John Umaru_F2

Figure 2. Leaves of Leptadenia hastata.

UV-visible Analysis: The UV-visible spectroscopy is usually conducted to confirm the synthesis of ZnO Nanoparticles. Conducting electrons start oscillating at a certain wavelength range due to surface Plasmon resonance (SPR) effect. Figure 5 represents the UV-visible spectra of freshly prepared Leptadenia hastata ZnO Nanoparticles. Peak observed at 380 nm clearly demonstrates the presence of ZnO Nanoparticles in the reaction mixture. Initial peak obtained at range of 420 nm got further raised due to oscillation of more electrons after 5 hrs which reports the continuous synthesis of Leptadenia hastata ZnO Nanoparticles.

JMG 304_Issac John Umaru_F5

Figure 5. UV-vs spectrum of Leptadenia hastata leaf ZnO Nanoparticles.

Antibacterial Activity of ZnO Nanoparticles (NPs) of Leptadenia hastata fresh leaf: Anti-bacterial effect of Leptadenia hastata fresh leaf ZnO Nanoparticles was tested against Staphylococcus aureus, Escherichia coli, Klebsielia Pneumonia. Tetracycline disc was used as a standard, from the table 1 the result clearly demonstrated that the nanoparticles showed antibacterial activity in a dose dependant manner. Figure 6 and Table 1. A significant inhibition was observed at 25 ppm to 1000 ppm, maximum zone of inhibition was observed against all the bacteria at 1000 ppm with increase in concentration of the ZnO nanoparticles in all the gram-ve and gram +ve bacterium (Staphylococcus aureus, Escherichia coli, Klebsielia Pneumonia) of12.53 ± 0.12 mm, 12.34 ± 0.10 mm and 12.13 ± 0.12 mm, respectively. Minimum zone of inhibition was observed against all the bacterium at 25 ppm. However, the zone of growth Inhibition obtained using the nanoparticle was much significant when compared to the standard disc (Tetracycline) used which depicts the need of considering nanoparticle as an agent to compliment in the fight of resistance bacteria in the field of medical science. The entire tests were done in triplicate. The zinc oxide nanoparticles are inhibiting the microbial growth in in-vitro antimicrobial activities.

Table 1. Effect of Leptadenia hastata leaf zinc oxide (ZnO) nanoparticle on Staphylococcus aureus, (+ve), Escherichia coli (–ve) and Klebsielia Pneumonia (+ve)

Concentration (ppm)

Escherichia coli (Gram–ve),

Staphylococcus aureus, (Gram +ve)

Klebsielia Pneumonia (Gram +ve)

Control(tetracycline)

13.15 ± 0.10

13.12 ± 0.81

13.10 ± 1.10

25

9.97 ± 0.21b

7.75 ± 0.07

10.77 ± 0.23

50

11.20 ± 0.20

11.60 ± 0.10b

11.55 ± 0.07

100

11.85 ± 0.07

11.00 ± 0.10

11.65 ± 0.07

250

11.90 ± 0.14

11.67 ± 0.14

11.95 ± 0.07b

500

11.99 ± 0.10b

12.17 ± 0.25

11.97 ± 0.35

1000

12.53 ± 0.12a

12.34 ± 0.10a

12.13 ± 0.12a

Values are Mean ± SD

aSignificantly (p< 0.05) higher compared to different concentration in each column

bSignificantly (p< 0.05) higher compared at the same concentration in each row

JMG 304_Issac John Umaru_F6

Figure 6. Showing the growth inhibition of Leptadenia hastata ZnO Nanoparticles

Conclusion

The study on the biosynthesis of ZnO nanoparticles using fresh leaf extract from Leptadenia hastata was carried out. This green synthesis was found to be eco-friendly, non-toxic and less usage of chemicals compared to the physical and chemical method. The presence of phytochemical constituents in the leaf extract helps in the synthesis of the ZnO nanoparticles by inducing redox reaction. The functional groups of phytochemicals such as amine, alkane and hydroxyl groups induced the formation of nanoparticles which are widely seen in the secondary metabolites, such as terpenoids, flavonoids, alkaloids. The preliminary confirmation of the ZnO nanoparticles through was measured using the Uv-visible spectroscopy at 380 nm, the SEM analysis demonstrate the size of the nanoparticles and the antibacterial activity of the Leptadenia hastata ZnO nanoparticles has confirmed the potential of the nanoparticles as an agent against bacterial.

Acknowledgement

The authors wish to acknowledge the research grant 07(ZRC05/1238/2015(2) Provided by Universiti Malaysia Sarawak which has resulted to this article.

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Brief Review of Enhanced External Counterpulsation (EECP)

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DOI: 10.31038/IMCI.2020311

Abstract

EECP (Enhanced External Counterpulsation) has been approved by the FDA (Food and Drug Administration) for management of refractory angina (class IIb). EECP uses 3 sets of pneumatic cuffs that sequentially contract during diastole, increasing aortic diastolic pressure, augmenting coronary blood flow and central venous return. EECP has been shown to improve angina symptoms, reduce nitroglycerin use, and improve exercise tolerance in patients with chronic stable angina. EECP has also been shown to be safe and beneficial in patients with symptomatic stable congestive heart failure. It’s been postulated that cardiac benefits of EECP are mediated though VEGF and Nitric oxide mediated vasodilatation and angiogenesis.  The Food and Drug Administration (FDA) has approved EECP therapy for heart failure patients.

Keywords

EECP (Enhanced External Counterpulsation), Angina Pectoris, Congestive Heart Failure, PCI (Percutaneous Coronary Intervention), Myocardial Infarction (MI), the International EECP Patient Registry (IEPR)

Introduction

Enhanced External Counterpulsation (EECP) is a noninvasive technology used in the United States to treat chronic severe angina that is refractory to medical management, especially in patients for whom intervention is contraindicated due to other metabolic conditions. (Class IIB) [1]. It was cleared by U.S. FDA in 1995 [2]. It is currently recommended as class IIB by the American Heart Association, as well as Chinese Medical Association, for refractory angina pectoris [3].

The evaluation of hemodynamic effects of counterpulsation was first studied in the mid-1960s. Water filled bags were wrapped around legs of patients with cardiogenic shock.  Soroff and colleagues first studied this technique in humans in 1965 [4].

One course of EECP involves 35 sessions designed as 1 hour sessions per day, 5 days per week

Methods & Materials

The technique involves sequential compression of 3 sets of pneumatic cuffs applied to the calves, thighs, and abdomen which are timed with early diastole of the heart based on EKG monitoring [5].  The patient is attached to finger plethysmograph and cardiac monitoring.  Inflation of the cuffs is timed with the R wave on EKG which corresponds with the diastole. This is followed by deflation just before systole. The main purpose is to enhance cardiac coronary perfusion during diastole by enhancing cardiac return and also enhancing backflow into coronaries during diastole. The deflation just before systole reduces the afterload by reducing systolic pressure and creating run-off, thus enhancing the cardiac output with reduced cardiac workload [3].

IMCI 20 - 301_Tak T-F1

Figure 1. Schematic of the sequential diastolic inflation and systolic deflations of leg cuffs during EECP therapy.

The magnitude of clinical benefit of EECP is measured as a ratio of diastolic to systolic pressure during EECP called Effectiveness Ratio (ER).  It has been shown by Suresh, et al that the maximum benefit of EECP is obtained at an ER of 1.5–2. The goal of treatment for coronary disease is diastolic blood pressure /systolic blood pressure =Q>1.2 after counterpulsation [6]. However, Micheals, et al also reported that there is no additional benefit to higher ER with reduction of angina.  The clinical relevance of ER is confusing since it has also been shown that there is clinical benefit to patients with EECP in the absence of optimal ER.

IMCI 20 - 301_Tak T-F2

Figure 2. Finger plethysmogram showing the changes in vascular flow rate during EECP therapy; blue curve indicates blood flow without EECP; brown curve shows augmentation of blood flow as EECP cuff is inflated. [S: systole, D: diastole, T: transition (cuff inflation begins), EDP: end-diastolic pressure.]

Patients are screened at the time of referral for potential contraindications which include, but are not limited to, arrhythmias that interfere with machine triggering, bleeding diathesis, active thrombophlebitis, severe lower extremity peripheral vascular disease, presence of a documented aortic aneurysm requiring surgical repair, and pregnancy [1].

The 35-treatment sessions are typically completed once daily, Monday through Friday, for 7 weeks. However, extensions may be warranted for patients who display a late onset of improvement in symptoms. Patients are discouraged from missing scheduled sessions as lack of adherence to protocol may negatively affect the overall results.  Body weight, blood pressure, heart rhythm, and symptom assessment are recorded by the technician prior to each treatment session. The intended 60-minute treatment session is completed with as few interruptions as possible to produce the full benefit of the treatment. Although the treatment is generally well tolerated, blistering and bruising of the legs, leg pain, and back pain may occur in some patients [1].

Results

There have been multiple invasive studies that evaluated the hemodynamic effect of EECP on coronary flow. Michaels, et al evaluated the change in diastolic and systolic pressure in the coronaries, aorta, and intracardiac pressure while undergoing EECP with the help of left heart catheterization [7].  Central aortic pressure, intracoronary pressure, and intracoronary Doppler flow was measured while the patient was undergoing EECP in the Catheterization laboratory. The results unequivocally showed that there is a clear increase in coronary blood flow velocity and pressure during diastole with inflation of the cuff representing diastolic augmentation of the blood flow. Left ventricular afterload was reduced during systole with deflation, reducing the left ventricular work.

In a study by Sahebjami, et al, it was found that the frequencies of angina were linearly reduced in both diabetics and non diabetics after EECP therapy, but it was significant only in non-diabetic patients. Furthermore, the angina reduction only started occurring in the 5th week. It appears that diabetes is one of the obstacles for successful EECP therapies [8].

In an arteriogenesis network trial, it was shown that EECP improves fractional flow reserve and coronary collateral flow index. It has also been shown that EECP improves global left ventricular function in patients with coronary artery disease [9]. This was demonstrated by left heart catheterization at baseline and in 7 weeks after EECP therapy in patients with stable coronary artery disease with at least one stenosis amenable to PCI.  Invasive measurements of FFR and pressure derived collateral flow index were measured. The results were compared to a control group with no EECP. Results showed direct evidence for stimulation of coronary angiogenesis. This study indicates other modalities of benefit from EECP other than the acute hemodynamic changes.

EECP has also shown to benefit endothelial function by enhancing the release of nitric oxide and regulating endothelin-1 release, both of which play a role in maintaining vascular hemostasis. Masuda et al showed that there is a significant increase in plasma NO levels and reduction in neuro hormonal factors like human ANP and BNP after EECP treatment [10]. It also showed improved perfusion at rest and after dipyridamole in ischemic territories of myocardium on PET study after EECP, suggesting that development and recruitment of collateral vessels is one of the mechanisms of benefit [10].

EECP was shown to be effective in treating angina in patients with ischemic cardiomyopathy after CABG [11] although this is a small study with only 40 subjects. More studies are needed in this group of patients before it can be formally recommended.

Discussion

Further studies are needed to delineate the exact mechanism of both long term and short term benefit from EECP in chronic angina. Wu E et al conducted a qualitative study assessing the experiences of patients undergoing EECP therapy for refractory angina. The study showed that the patients were not that familiar with this treatment option prior to therapy [12]. This demonstrates the need for further education of patients and providers since it is a safe treatment modality with relatively limited side effects for refractory angina pectoris and severe congestive heart failure which also improves quality of life.

References

  1. Sharma U, Ramsey HK, Tak T (2013) the role of enhanced external counterpulsation therapy in clinical practice. Clin Med Res 11: 226–32.
  2. Wu E, Broström A, Mårtensson J (2019) Experiences of Undergoing Enhanced External Counterpulsation in Patients with Refractory Angina Pectoris: A Qualitative Study. J Cardiovasc Nurs 34: 147–158.
  3. Yang DY, Wu GF (2013) Vasculoprotective properties of enhanced external counterpulsation for coronary artery disease: beyond the hemodynamics. Int J Cardiol 166: 38–43.
  4. Soroff HS, Birtwell WC, Giron F, Collins JA, Deterling RA (1965) Support of the systemic circulation and left ventricular assist by synchronous pulsation of extramural pressure. Surg Forum 16: 148–50.
  5. Medical Advisory Secretariat (2006) Enhanced External Counterpulsation (EECP): An Evidence-Based Analysis. Ont Health Technol Assess Ser6: 1–70.
  6. Li B, Chen S, Qi X, Wang W, Mao B, et al (2018) The numerical study on specialized treatment strategies of enhanced external counterpulsation for cardiovascular and cerebrovascular disease. Med Biol Eng Comput 56: 1959–1971.
  7. Michaels AD, Accad M, Ports TA, Grossman W (2002) Left ventricular systolic unloading and augmentation of intracoronary pressure and Doppler flow during enhanced external counterpulsation. Circulation 106: 1237–42.
  8. Sahebjami F, Madani FR, Komasi S, Heydarpour B, Saeidi M, et al (2019) Refractory angina frequencies during 7 weeks treatment by enhanced external counterpulsation in coronary artery disease patients with and without diabetes. Ann Card Anaesth 22: 278–282.
  9. Maryam Esmaeilzadeh, Arsalan Khaledifar, Majid Maleki, Anita Sadeghpour, Niloufar Samiei, et al (2009)  Evaluation of left ventricular systolic and diastolic regional function after enhanced external counterpulsation therapy using strain rate imaging. European Journal of Echocardiography 10: 120–126.
  10. D Masuda, R Nohara, T Hirai, K Kataoka, L.G Chen, et al (2001) Enhanced external counterpulsation improved myocardial perfusion and coronary flow reserve in patients with chronic stable angina. Evaluation by13N-ammonia positron emission tomography. European Heart Journal 22: 1451–1458.
  11. Abdelwahab AA, Elsaied AM (2018) Can enhanced external counterpulsation as a non-invasive modality be useful in patients with ischemic cardiomyopathy after coronary artery bypass grafting? Egypt Heart J 70: 119–123.
  12. Wu E, Broström A, Mårtensson J (2019) Experiences of Undergoing Enhanced External Counterpulsation in Patients With Refractory Angina Pectoris: A Qualitative Study. J Cardiovasc Nurs 34:147–158.

Sensory Stimulation and Bradykinesia Aponeurotic Stimulation Effects on Parkinson Bradykinesia

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Abstract

Introduction: Bradykinesia is one of the main motor symptoms in Parkinson Disease (PD). Studies have shown that patients with PD exhibit bradykinesia because they have difficulties integrating multi-sensorial information, mainly proprioception, leading to difficulties in modulating the velocity of self-paced voluntary movements. We hypothesized that stimulation of aponeurotic tissues of the upper limb, which contains numerous types of mechanoreceptors, could therefore have a therapeutic effect on PD-induced bradykinesia.

Method: We investigated changes in bradykinesia in patients with PD after aponeurotic stimulation (AS) of tissues of upper limb muscles with a metallic hook, according to the diacutaneous fibrolysis method. A control group received placebo stimulation (PS) that consisted of manipulating the skin over the muscles that were the targets for AS treatment. We assessed symptoms of bradykinesia in a total of 10 patients with PD in terms of movement velocity for upward rotations of the outstretched arm and in terms of UPDRS motor score, before and after AS or PS treatment.

Results: Parkinson’s motor symptoms, as measured by the UPDRS motor scored, decreased for the AS group from 31.3±13.2 % to 26.8±12 % (p<0.003), whereas for the control group there was no significant difference after PS treatment. AS treatment also led to an increase in peak velocity at the shoulder (8.1±1.3°/s before vs. 10.2±1.1°/s after; p=0.037), whereas the placebo treatment induced no significant modifications.

Conclusions: The results of this pilot study suggest that aponeurotic stimulation directly improves motor output, with the potential of alleviating bradykinesia in patients with PD.

Introduction

Current knowledge attributes movement disorders in PD to a dysfunction of the basal ganglia-motor cortex circuits, but it is also known that abnormalities in the processing of peripheral afferents may interfere with movement execution [1]. Studies have shown that patients with PD rely excessively on visual information to guide movements [1–3] and that they present deficits in the conscious perception of limb and body motion (i.e. kinaesthesia) [4]. Exploring rehabilitation possibilities for PD-related movement disorders via sensory stimulation is therefore very attractive, especially since cutaneous and proprioceptive stimulation strongly activates both the olivo-cerebellum and basal ganglia networks [5–6]. In this light, we hypothesized that diacutaneous fibrolysis method, a form of aponeurotic manipulation, could be beneficial. By applying this approach on the triceps surae, Vezsely et al [7]. Showed that dorsi-flexion at the ankle increased while passive tension decreased. More importantly, tendon reflexes decreased, indicating a modification of proprioceptive information processing. To the extent that sensory processes may underlie bradykinesia in PD, aponeurotic stimulation could affect, and hopefully alleviate, some of these symptoms.

Methods

Participants

Ten participants gave written consent and the Ethical Committee of the “Hôpital Brugmann” (Brussels) approved the study. Table 1 shows the characteristics of each participant. Each participant continued their usual medical treatment and for those using deep brain electrical stimulation (DBS), the stimulation was turned on during the experiment.

Experimental procedure

Participants performed a pointing task consisting of an upward rotation of the outstretched arm around the shoulder joint, initiated after a self-timed delay. Patients were seated in front of a panel showing two targets and pointed at these targets with a laser pointer fixed to their index finger (Figure 1A). Movements of reflective markers attached to the upper limb were recorded in 3D at 100 Hz with an optoelectronic device (BTS Elite System).

An experimental session consisted of 10 pointing movements performed before and after 45 minutes of AS or PS treatment (see below). At the beginning and end of the session, a therapist performed the UPDRS test (part III: Motor evaluation) [8] concerning motor function. One week before the recording session, each patient was trained to perform the pointing movements at their own ‘natural’ velocity.

JCRM 2019-119 - Ana Bengoetxea Belgium_F1

Figure 1:

A) Experimental conditions. Seated subjects pointed with a laser to targets (diameter of 4 cm) located at a distance of 3.5m. The starting target was in the middle of the panel and the ending target 42 cm above. They were asked to perform the movements with the upper arm in an extended position (shoulder movements around a nominal position of 90° flexion, with the elbow fully extended).

B) Mean peak shoulder velocity (Vy) before (ordinate) versus after (abscissa) treatment. Open circles represent the PS treatment group and black circles the AS treatment group. Dashed lines show the range (mean±SD) for the healthy control group.

C) Mean and SD for Vy before and after PS and AS treatment, and for healthy control subjects.

A second therapist imposed passive movements of the patient’s shoulder and elbow used to localize the muscles manifesting the greatest rigidity. In general the main muscles manipulated were: the superior or inferior trapezium, the anterior and posterior deltoid, the external or internal rotators of the shoulder, the pectoralis major, the triceps brachii and the brachialis. AS treatment consisted of back-and-forth displacements of the aponeurotic tissues enrobing the heads of the target muscles, applied by a hook perpendicular to the axis of the muscular fibers. PS stimulation consisted of manipulating the skin over the same target muscles. The second therapist was the only person to know if AS or PS was applied to a given patient.

We computed the peak angular velocity for rotation at the shoulder (Vy) from the 3D marker data for each pointing movement. Statistical analyses consisted of repeated measure ANOVA (Statistica®, StatSoft) with treatment (AS or PS) and repetition (before or after treatment) as within-subjects factors, applied to Vy and to UPDRS scores.

Results

Before manipulation the AS and PS groups presented no significant differences in their motor UPDRS scores. ANOVA showed a significant cross-effect (F(1, 9)=8.76, p=0.016) between test repetition (before or after treatment) and treatment type (AS or PS). The subsequent Bonferroni-corrected post-hoc analyses showed a highly significant decrease of the UPDRS motor score from 31.3±13.2% to 26.8±12 % after AS treatment compared to before (p<0.003), whereas for the PS treatment group there was no significant difference (Table 1).

Table 1. Profile and clinical features of subjects. UPDRS score for part III (Motor evaluation) and scores on selected items before and after treatment.

JCRM 2019-119 - Ana Bengoetxea Belgium_F2

We then assessed what items of the UPDRS presented the main changes after treatment. Table 1 shows the values before and after treatment for 6 specific items (the values correspond only to the treated upper limb); 3 of them corresponding to the ‘triad’ of main symptoms of PD disease and the 3 others corresponding to hand movements. It is interesting to note that treatment produced a significant cross-effect between the ‘hand’ and ‘triad’ groups (F(1, 9)=6.024, p=0.04). After treatment the mean of hand-movement items decreased from 1.36±0.16 to 1.06±0.18 (Bonferroni post-hoc p<0.01), whereas the mean values of the triad symptoms remained stable (1.26±0.13 and 1.23±0.15, respectively).

Figure 1B shows Vy measured for our participants, compared to the mean±SD of “natural” shoulder velocity for 10 healthy control subjects (area between dashed lines) who performed this pointing movement after the same training as our patients. Patients presented significantly lower Vy on average than the control group (8.8±0.8°/s vs. 13.8±1.5°/s), however, we found no difference in Vy between our two patient groups prior to treatment (8.2±1.3°/s for AS vs. 9.9±1.9°/s for PS). Repeated measures ANOVA showed a significant main effect of test period (before and after treatment) on Vy (F(1,9)=5.7, p=0.04). Bonferroni post-hoc tests showed that treatment modified Vy only for the AS group (10.23±1.13°/s after versus 8.17±1.28°/s before; p=0.037) whereas the PS treatment induced no significant modifications (Figure 1C).

Discussion

Aponeurotic stimulation increased the shoulder velocity for vertical pointing movements (Vy) and improved the velocity of hand gestures (UPDRS’s items), indicating a decrease of bradykinesia in our PD patients. It is worth noting that our participants performed these movements under conditions that increase the risk of bradykinesia, because they were voluntary, internally driven movements with accuracy constraints [9] and because repeating movements makes the symptoms more prominent [10]. It is also worth noting that our treatment produced a positive effect on the UPDRS items concerning repetitive sequential movements of isolated fingers, hand and wrist (items 23, 24 and 25 respectively).

Conclusions

More research is needed to understand the mechanisms of motor output improvement brought on by the aponeurotic stimulation. Whatever the cause, however, the results from this pilot study indicate that aponeurotic manipulation could provide a new therapeutic approach to improve the quality of every-day movements in patients with PD.

Acknowledgments

This work was funded by the Belgian National Fund for Scientific Research (FNRS), the Research Fund of the Université Libre de Bruxelles (Belgium), the Belgian Federal Science Policy Office, the European Space Agency (AO-2004, 118), the FP7 support (ICT-247959-MINDWALKER). The authors thank J. McIntyre for fruitful comments about the manuscript, J. Burnotte for teaching all the subtleties of the aponeurotic technique, all the persons who participated in the study, the LNMB team for rich discussions, E. Hortmanns and T. d’Angelo for expert technical assistance and C. de Scoville for administrative assistance.

References

  1. Abbruzzese G, Berardelli A. (2003) Sensorimotor integration in movement disorders. Mov Disord 18(3): 231–40. [Crossref]
  2. Adamovich SV, Berkinblit MB, Hening W, Sage J, Poizner H. (2001) The interaction of visual and proprioceptive inputs in pointing to actual and remembered targets in Parkinson’s disease. Neuroscience 104 (4): 1027–41. [Crossref]
  3. Poizner H, Feldman AG, Levin MF, Berkinblit MB, Hening WA, Patel A, Adamovich SV. (2000) The timing of arm-trunk coordination is deficient and vision-dependent in Parkinson’s patients during reaching movements. Exp Brain Res 133(3): 279–92. [Crossref]
  4. Konczak J, Krawczewski K, Tuite P, Maschke M. (2007) The perception of passive motion in Parkinson’s disease. J Neurol 254(5): 655–63. [Crossref]
  5. Ekerot CF, Garwicz M, Jörntell H. (1997) The control of forelimb movements by intermediate cerebellum. Prog Brain Res 114: 423–9. [Crossref]
  6. Hoshi E, Tremblay L, Féger J, Carras PL, Strick PL. (2005) The cerebellum communicates with the basal ganglia. Nat Neurosci 8(11): 1491–3. [Crossref]
  7. Vezsely M, Guissard N, Duchateau J. (2000) Contribution à l‘étude des effets de la fibrolyse diacutanée sur le triceps sural. Annales de kinésithérapie 27: 54–59.
  8. Fahn S, Elton RL, Members of the UPDRS Development Committee. (1987) The Unified Parkinson’s Disease Rating Scale. In Fahn S, Marsden CD, Calne DB, Goldstein M, editors. Recent developments in Parkinson’s disease, vol 2. Florham Park, NJ: Macmillan Health Care Information 153–163, 293–304
  9. Sheridan MR, Flowers KA. (1990) Movement variability and bradykinesia in Parkinson’s disease. Brain 113 ( Pt 4): 1149–61 [Crossref]
  10. Agostino R, Berardelli A, Formica A, Stocchi F, Accornero N, Manfredi M. (1994) Analysis of repetitive and nonrepetitive sequential arm movements in patients with Parkinson’s disease. Mov Disord 9(3): 311–4 [Crossref]

Cardiovascular Disease and the Evidence for Cystatin C as a Cardiovascular Risk Predictor in Native and Kidney Transplant Populations

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DOI: 10.31038/JCCP.2020311

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Cardiovascular disease (CVD) in the form of coronary heart disease (CHD), stroke, or heart failure (HF) affects 9% of adults in the United States (U.S.) over the age of 20. When hypertension (HTN) is included in this grouping of CVD, its prevalence swells to 48% [1]. Meanwhile, peripheral arterial disease (PAD) has an estimated prevalence of 7.2% in American adults over the age of 40 [2]. Chronic kidney disease (CKD), defined as kidney injury or diminished glomerular filtration rate (GFR) lasting at least 3 months, is commonly associated with CVD and is an independent risk factor for CVD [3,4]. Furthermore, the risk of CVD in patients with CKD is significant, and patients with CKD are more likely to suffer from CVD than to progress to end stage renal disease (ESRD) [5]. There have been a number of pathophysiologic mechanisms posited with regards to the development of CVD in the setting of CKD. Abnormal vascular tone, hypertension, and endothelial injury can arise in CKD due to alterations in normal water and salt balance as well as activation of the renin, angiotensin, aldosterone system (RAAS) [6]. Runaway RAAS activity is also responsible for pathologic cardiac remodeling [6]. Hyperphosphatemia is a consequence of aberrant bone and mineral metabolism in CKD, and may cause direct vascular injury [7]. Hyperkalemia in the setting of CKD has been associated with cardiac conduction abnormalities [6]. The uremic milieu itself has been shown to contribute to CVD and anemia due to disruption of the erythropoietin (EPO) axis and functional iron deficiency have a correlative relationship to adverse cardiovascular outcomes [6,8]. In summary, there are numerous pathophysiologic mechanisms that may explain the increased CVD risk and events across various stages of CKD.

 It stands to reason then that estimated GFR (eGFR), as a measure of kidney function, would have some predictive value for cardiovascular outcomes. Indeed, a relationship has been described between declining eGFR and worsening risk for CVD. A few representative studies are highlighted here. Lees et al. found an association between decreasing eGFR and increased adjusted hazard ratios for adverse outcomes consisting of all-cause mortality, CVD, and ESRD [9]. Specifically, hazard ratios for adverse outcomes tended to be highest among patients with eGFR ranging from 15–30 mL/min/1.73m2, representing the group of patients with the lowest measured eGFR included in the study [9]. Guo et al. focused their investigation on the magnitude of eGFR decline over time and the effect of this change on risk for all-cause mortality and CVD events [10]. Their results had similar implications, as patients who experienced greater losses in GFR from one year to the next were at higher risk of mortality and CVD [10]. Therefore in addition to surveillance of renal function, it is imperative to define CV risk in CKD patients. In clinical practice, estimated GFR using creatinine (Cr) based eGFR equations has been the most commonly used approach to monitor renal function despite its limitations due to non-GFR determinants not accounted for in commonly used eGFR equations such as muscle mass and dietary protein intake for example [11,12]. Cystatin C (Cys C), another endogenous marker for estimating eGFR, is not influenced by body mass or dietary protein. It has been shown to have several non-GFR determinants including: elevated markers of inflammation, dyslipidemia, obesity, implying that inflammation and atherosclerosis may affect the accuracy of CysC-eGFR [12,13,14]. However the data has been overwhelmingly supportive of Cys C based eGFR as a better estimate of kidney function compared to Cr only eGFR in the native kidney population [15]. Furthermore, CysC and CysC eGFR have been shown to correlate with mortality and CVD [9,16,17]. Revisiting the study by Lees et al., though CVD risk was generally higher as Cr-eGFR and CysC-eGFR decreased CysC-eGFR was a more accurate predictor of mortality and cardiovascular events than Cr-eGFR [9]. Garcia-Carretero et al. found similar results with diminished CysC-eGFR being associated with higher hazard ratios of cardiovascular morbidity and mortality than Cr-eGFR [17].

In the kidney transplant (KTx) population, CVD remains the leading cause of death with a functioning graft [18]. Individuals in the KTx population remain subject to excess CVD risk due to recipient and donor characteristics which include: graft function, diabetes, history of dialysis prior to transplant, acute rejection events, and pre-transplant history of CVD [18,19]. Given significant differences between KTx patients and patients with native kidneys, it is appropriate to ask whether or not the evidence in support of Cys C as a preferred marker of eGFR and predictor of CVD risk holds true in the KTx patient population. With regards to the first question, Yang et al. found no significant difference between measured GFR and eGFR based on Cys C, while eGFR based on Cr significantly underestimated measured GFR [20]. However, Keddis et al. also compared the accuracy of Cr-eGFR and CysC-eGFR in a cohort of stable KTx recipients [21]. They found that CysC-eGFR measurements showed greater bias than Cr-eGFR, with greater inaccuracy and underestimation of GFR compared to Cr-eGFR [21]. In fact, Cys C was found to have more non-eGFR determinants than Cr in the KTx population [12]. In another study, Foster et al. examined the association of diminished CysC-eGFR and Cr-eGFR with mortality, cardiovascular events, and kidney failure [22]. They found that diminished CysC-eGFR was associated with significantly increased risk for cardiovascular events after adjustment for known CV risk factors. Diminished Cr-eGFR was also significantly associated with an increased risk for cardiovascular events. However, this relationship was not continuous and disappeared with multivariable adjustment [22]. Further studies are needed to validate the relationship of CysC-eGFR with CV events and mortality in the KTx population. In conclusion, there is strong evidence to support that Cys C and CysC-eGFR provide better CV risk stratification in the native and transplant kidney populations compared to Cr. Further studies are needed to guide the value of routine measurements and the clinical implications of identified CV risk using Cys C.

References

  1. Benjamin EJ, Muntner P, Alonso A, Bittencourt MS, Callaway CW, et al. (2019) Heart Disease and Stroke Statistics-2019 Update: A Report From the American Heart Association. Circulation 139: 56–528. [Crossref]
  2. Allison MA, Ho E, Denenberg JO, Langer RD, Newman AB, et al. (2007) Ethnic-specific prevalence of peripheral arterial disease in the United States. Am J Prev Med 32: 328–333. [Crossref]
  3. (2013) Chapter 1: Definition and classification of CKD. Kidney Int Suppl (2011) 3: 19–62. [Crossref]
  4. Sarnak MJ, Levey AS, Schoolwerth AC, Coresh J, Culleton B, et al. (2003) Kidney disease as a risk factor for development of cardiovascular disease: a statement from the American Heart Association Councils on Kidney in Cardiovascular Disease, High Blood Pressure Research, Clinical Cardiology, and Epidemiology and Prevention. Circulation 108: 2154–2169. [Crossref]
  5. Sarnak MJ (2003) Cardiovascular complications in chronic kidney disease. Am J Kidney Dis 41: 11–17. [Crossref]
  6. Tomey MI, Winston JA (2014) Cardiovascular pathophysiology in chronic kidney disease: opportunities to transition from disease to health. Ann Glob Health 80: 69–76. [Crossref]
  7. Tonelli M, Pannu N, Manns B (2010) Oral phosphate binders in patients with kidney failure. N Engl J Med 362: 1312–1324. [Crossref]
  8. Vanholder R, Glorieux G, Lameire N, European Uremic Toxin Work G (2003) Uraemic toxins and cardiovascular disease. Nephrol Dial Transplant 18: 463–466. [Crossref]
  9. Lees JS, Welsh CE, Celis-Morales CA, Mackay D, Lewsey J, et al. (2019) Glomerular filtration rate by differing measures, albuminuria and prediction of cardiovascular disease, mortality and end-stage kidney disease. Nat Med 25: 1753–1760. [Crossref]
  10. Guo Y, Cui L, Ye P, Li J, Wu S, et al. (2018) Change of Kidney Function Is Associated With All-Cause Mortality and Cardiovascular Diseases: Results From the Kailuan Study. J Am Heart Assoc 7: e010596.
  11. Tangri N, Stevens LA, Schmid CH, Zhang YL, Beck GJ, et al. (2011) Changes in dietary protein intake has no effect on serum cystatin C levels independent of the glomerular filtration rate. Kidney Int 79: 471–477. [Crossref]
  12. Foster MC, Levey AS, Inker LA, Shafi T, Fan L, et al. (2017) Non-GFR Determinants of Low-Molecular-Weight Serum Protein Filtration Markers in the Elderly: AGES-Kidney and MESA-Kidney. Am J Kidney Dis 70: 406–414. [Crossref]
  13. Ferguson TW, Komenda P, Tangri N (2015) Cystatin C as a biomarker for estimating glomerular filtration rate. Curr Opin Nephrol Hypertens 24: 295–300. [Crossref]
  14. Rule AD, Bailey KR, Lieske JC, Peyser PA, Tuner ST (2013) Estimating the glomerular filtration rate from serum creatinine is better than cystatin C for evaluating risk factors associated with chronic kidney disease. Kidney Int 83: 1169–1176. [Crossref]
  15. Inker LA, Schmid CH, Tighiouart H, Eckfeldt JH, Feldman HI, et al. (2012) Estimating glomerular filtration rate from serum creatinine and cystatin C. N Eng J Med 367: 20–29. [Crossref]
  16. Luo J, Wang LP, Hu HF, Zhang L, Li YL, et al. (2015) Cystatin C and cardiovascular or all-cause mortality risk in the general population: A meta-analysis. Clin Chim Acta 450: 39–45. [Crossref]
  17. Garcia-Carretero R, Vigil-Medina L, Barquero-Perez O, Goya-Esteban R, Mora-Jimenez I, et al. (2017) Cystatin C as a predictor of cardiovascular outcomes in a hypertensive population. J Hum Hypertens 31: 801–807. [Crossref]
  18. Stoumpos S, Jardine AG, Mark PB (2015) Cardiovascular morbidity and mortality after kidney transplantation. Transpl Int 28: 10–21. [Crossref]
  19. Kasiske BL, Chakkera HA, Roel J (2000) Explained and unexplained ischemic heart disease risk after renal transplantation. J Am Soc Nephrol 11: 1735–1743. [Crossref]
  20. Yang Y, Kim KY, Hwang I, Yim T, Do W, et al. (2017) Cystatin C-Based Equation for Predicting the Glomerular Filtration Rate in Kidney Transplant Recipients. Transplant Proc 49: 1018–1022. [Crossref]
  21. Keddis MT, Amer H, Voskoboev N, Kremers WK, Rule AD, et al. (2016) Creatinine-Based and Cystatin C-Based GFR Estimating Equations and Their Non-GFR Determinants in Kidney Transplant Recipients. Clin J Am Soc Nephrol 11: 1640–1649. [Crossref]
  22. Foster MC, Weiner DE, Bostom AG, Carpenter MA, Inker LA, et al. (2017) Filtration Markers, Cardiovascular Disease, Mortality, and Kidney Outcomes in Stable Kidney Transplant Recipients: The FAVORIT Trial. Am J Transplant 17: 2390–2399. [Crossref]

Showcase to illustrate how the web-server pLoc_balmEuk is working

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DOI: 10.31038/JMG.2020321

Short Communication

Recently, a very powerful web-server predictor has been established for identifying the subcellular localization of a protein based on its sequence information alone for the multi-label systems 1], in which a same protein may occur or move between two or more location sites and hence needs to be marked with the multi-label approach 2]. The web-server predictor is called “pLoc_bal-mEuk”, where “bal” means the web-server has been further improved by the “balance treatment” 3-9], and “m” means the capacity able to deal with the multi-label systems. To find how the web-server is working, please do the following.

Click the link at http://www.jci-bioinfo.cn/pLoc_bal-mEuk/, the top page of the pLoc_bal-mEuk web-server will appear on your computer screen, as shown in Figure 1. Then by following the Step 2 and Step 3 in 5], you will see the predicted results shown on Figure 2. Nearly all the success rates achieved by the web-server predictor for the eukaryotic proteins in each of the 22 subcellular locations are within the range of 90-100%, which is far beyond the reach of any of its counterparts.

JMG 2020-303_Kuo-Chen Chou_F1

Figure 1. A semi screenshot for the top page of pLoc_bal-mEuk (Adapted from 5]).

JMG 2020-303_Kuo-Chen Chou_F2

Figure 2. A semi screenshot for the webpage obtained by following Step 3 of Section 3.5 (Adapted from 5]).

Besides, the web-server predictor has been developed by strictly observing the guidelines of “Chou’s 5-steps rule” and hence have the following notable merits (see, e.g., 10-90] and three comprehensive review papers 2, 91, 92]: (1) crystal clear in logic development, (2) completely transparent in operation, (3) easily to repeat the reported results by other investigators, (4) with high potential in stimulating other sequence-analyzing methods, and (5) very convenient to be used by the majority of experimental scientists.

For the fantastic and awesome roles of the “5-steps rule” in driving proteome, genome analyses and drug development, see a series of recent papers [2, 92-103] where the rule and its wide applications have been very impressively presented from various aspects or at different angles.

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