DEVELOPMENT OF PROGNOSTIC MODELS FOR CALCULATION OF ASYMMETRY COEFFICIENT OF CHEWING MUSCLE TONE AT VARIOUS STAGES OF ORTHODONTIC CORRECTION

Цель работы: Разработка прогностических моделей для оценки зависимости коэффициента асимметрии тонуса собственно жевательных мышц от функциональных параметров жевательных мышц и иммуноферментного состава ротовой жидкости на различных этапах ортодонтической коррекции. Материал и методы исследования: В исследовании приняли участие 82 пациента Детской клинической стоматологической поликлиники №2 г. Воронежа в возрасте от 6 до 12 лет с дистальной окклюзией зубных рядов, которым было рекомендовано лечение пластиночным аппаратом в модификации Шварца. Проводилась оценка функциональных параметров жевательных мышц: средней амплитуды биоэлектрической активности височных и подъязычных мышц, тонуса покоя и коэффициента асимметрии собственно жевательных мышц; количественное определение общих иммуноглобулинов G, А, M и секреторного иммуноглобулина A ротовой жидкости до начала лечения, через 3 и через 6 месяцев. Статистический анализ осуществлялся с использованием программ IBM SPSS Statistics 20, StatTech v. 1.2.0. Прогностическая модель, характеризующая зависимость количественной переменной от факторов, разрабатывалась с помощью метода множественной линейной регрессии. Результаты: Разработаны 2 прогностические модели. Полученные данные связаны с перестройкой функциональных параметров жевательной мускулатуры в результате ортодонтической коррекции. Вывод: Разработаны 2 прогностические модели для оценки зависимости коэффициента асимметрии тонуса собственно жевательных мышц от функциональных параметров жевательных мышц и иммуноферментного состава ротовой жидкости через 3 и 6 месяцев ортодонтической коррекции, которые позволят врачу грамотно выстроить план лечения, спрогнозировать его срок, повысить качество и эффективность диагностики The purpose of the work: Development of prognostic models for assessing the dependence of the asymmetry coefficient of the tone of the chewing muscles proper on the functional parameters of the chewing muscles and the immunoenzyme composition of the oral fluid at various stages of orthodontic correction. Material and methods of research: The study was attended by 82 patients of the Children's Clinical Dental Clinic No. 2 of Voronezh, aged 6 to 12 years, with distal occlusion of the dentition, who were recommended for treatment with a plate machine in the Schwartz modification. The functional parameters of chewing muscles were evaluated: the average amplitude of the bioelectric activity of temporal and sublingual muscles, the resting tone and the asymmetry coefficient of the chewing muscles themselves; quantification of total immunoglobulins G, A, M and oral fluid secretory immunoglobulin A before treatment, at 3 and 6 months. Statistical analysis was carried out using IBM SPSS Statistics 20, StatTech v. 1.2.0 (developer - Stattech LLC, Russia). A predictive model characterizing the dependence of a quantitative variable on factors was developed using the multiple linear regression method. Results: 2 prognostic models developed. The obtained data are related to reconfiguration of functional parameters of chewing muscles as a result of orthodontic correction. Conclusion: 2 prognostic models have been developed to assess the dependence of the asymmetry coefficient of the tone of the chewing muscles proper on the functional parameters of the chewing muscles and the immunoenzyme composition of the oral fluid after 3 and 6 months of orthodontic correction, which will allow the doctor to competently build a treatment plan, predict its duration, increase the quality and effectiveness of diagnosis

Analyzing the Role of Anal Sphincter Pressure in Rectocele Formation

Purpose: Constipation is a common entity in society with various factors in the etiology. In this study, we evaluated the role of anal sphincter pressure of patients who refer to surgery clinic with complaint of constipation.Methods: Sixty patients who refer to surgery clinic with complaint of constipation and were diagnosed with constipation due to Rome III criteria between July 2010 and September 2014. These patients were evaluated with defecography and were divided into 2 groups based on presence of rectocele. Both groups’ anal sphincter pressures were evaluated using anal manometry and findings were compared.Results: The patients with rectocele and without rectocele using defecography were inspected with anal manometry regarding resting tone pressure, squeeze pressure, maximum squeeze pressure and simulated defecation response pressure, first sensation volume, urge sensation volume, and maximum tolerable volume. Results were compared and no significant difference was found regarding groups with rectocele and without rectocele (P > 0.05).Conclusion: We have proved the hypothesis arguing that increased sphincter pressures do not play a role in the formation of rectocele by inducing an obstruction and the formation of dilation in proximal bowel, and demonstrated that the presence of rectocele is not dependent on an increase in sphincter pressures.

Prediction of Ergogenic Mouthguard Effects in Volleyball: A Pilot Trial

Dental occlusion may affect static and dynamic balance. The effects of a mouthguard on pinpoint accuracy in volleyball were investigated in 28 players who completed a volleyball specific test. Also, masticatory electromyographic tests were performed. The mean pinpoint accuracy was significantly higher with a mouthguard (68.6±9.3 vs. 64.0±7.0 points from 100; p< 0.006). However, differential mouthguard effects were seen, and three subgroups were classified: Group 1 (markedly improved pinpoint accuracy), Group 2 (improved pinpoint accuracy), and Group 3 (reduced pinpoint accuracy). Group 1 had a high masseter resting tone, the masseter activity was low in MVC (maximum voluntary clench) and increased in BOC (maximum bite on cotton rolls; p< 0.04). This indicates a masseter weakness, which would be compensated by a mouthguard. In Group 2, the masseter activity in MVC was high-normal with an imbalance which was improved in BOC (p< 0.01), indicating a possible mouthguard benefit. In Group 3, MVC and BOC were in a high-normal range and showed no relevant deficits. In these subjects the mouthguard had adverse effects. Overall, subjects with masticatory deficits had a benefit from the mouthguard in pinpoint accuracy. Positive or negative mouthguard responders may be detectible from electromyographic tests.

Uterine Contraction Parameters Before and During the Pre-Epidural Fluid Bolus: A Pilot Study

Background: The first stage of labor is significantly longer with epidural analgesia use, implying an alteration in uterine contractility. Although the pre-epidural fluid bolus is used with every epidural and affects as many as 80% of laboring women, its effects on uterine contraction parameters are unknown. Design: Using a retrospective descriptive repeated measures design, we compared uterine contraction parameters including frequency, duration, peak intensity, resting tone, and Montevideo units at baseline and during the intravascular pre-epidural fluid bolus (Bolus) epochs for healthy laboring women at term gestation undergoing augmentation or induction. Method: Contraction parameters were compared using data from fetal monitor strips with intrauterine pressure catheter instrumentation. Results: No significant differences were found between epochs for women receiving constant Pitocin dosages ( n = 10) using Wilcoxon signed rank tests at .05 α level, but all parameters trended in the direction of improved contractility except frequency, which was unchanged. Conclusions: These pilot study findings do not support the proposal that the pre-epidural fluid bolus is a contributor to decreased uterine contractility in any parameter. It is possible that the bolus improved myometrial perfusion and metabolic function in the contracting and resting states in less hydrated women.

An assessment of KIR channel function in human cerebral arteries

In the rodent cerebral circulation, inward rectifying K+ (KIR) channels set resting tone and the distance over which electrical phenomena spread along the arterial wall. The present study sought to translate these observations into human cerebral arteries obtained from resected brain tissue. Computational modeling and a conduction assay first defined the impact of KIR channels on electrical communication; patch-clamp electrophysiology, quantitative PCR, and immunohistochemistry then characterized KIR2.x channel expression/activity. In keeping with rodent observations, computer modeling highlighted that KIR blockade should constrict cerebral arteries and attenuate electrical communication if functionally expressed. Surprisingly, Ba2+ (a KIR channel inhibitor) had no effect on human cerebral arterial tone or intercellular conduction. In alignment with these observations, immunohistochemistry and patch-clamp electrophysiology revealed minimal KIR channel expression/activity in both smooth muscle and endothelial cells. This absence may be reflective of chronic stress as dysphormic neurons, leukocyte infiltrate, and glial fibrillary acidic protein expression was notable in the epileptic cortex. In closing, KIR2.x channel expression is limited in human cerebral arteries from patients with epilepsy and thus has little impact on resting tone or the spread of vasomotor responses. NEW & NOTEWORTHY KIR2.x channels are expressed in rodent cerebral arterial smooth muscle and endothelial cells. As they are critical to setting membrane potential and the distance signals conduct, we sought to translate this work into humans. Surprisingly, KIR2.x channel activity/expression was limited in human cerebral arteries, a paucity tied to chronic brain stress in the epileptic cortex. Without substantive expression, KIR2.x channels were unable to govern arterial tone or conduction.

Involvement of Alternative Calcium Conductance on Human Myometrial Contractile and Pharmacological Properties

Objective: This study aimed to investigate the physiological role of alternative calcium conduct once contractions triggered by oxytocin and PGF? in human myometrium. This conductance, supported by TRPC and TRPV channels, may provide alternative pathways to control either free intracellular and/or submembrane Ca2+ - concentrations, which in turn will modulate membrane polarization and contractile responses. Study design: Uterine biopsies were obtained from consenting women undergoing elective caesarian delivery at term without labor (N = 29). Isometric tension measurements were performed on uterine strips (n = 174). Amplitudes, frequencies and areas under the curve (AUC) of phasic contractions as well as resting tone were measured under various experimental conditions. Norgestimate, which has been shown to inhibit TRPC isoforms, was added to isolated organ baths to delineate their putative functional involvement. In order to assess the role of TRPV4 channels, rhythmic activity triggered by uterotonic drugs was determined in the absence and presence of either 1 ?M HC-067047 (TRPV4 antagonist) or 100 nM GSK1016790A (TRPV4 agonist). Addition of 50 nM iberiotoxin (IbTX) as well as of 10 ?M NS-1619 was also used to assess the involvement of GKCa channels in controlling uterine reactivity and contractility.Results: Micromolar concentrations of norgestimate consistently decreased the resting tone, frequency and maximal amplitude of oxytocin - and PGF2? - induced contractions. In contrast, the TRPV4 agonist GSK1016790A abolished the rhythmic contractions, resulting in a strong and reversible tocolytic effect. Addition of iberiotoxin (a GKCa blocker) reversed the effects of GSK1016790A, while NS1619 mimicked the rapid tocolytic effects of the TRPV4 agonist. Conclusion: Acute pharmacological inhibition of TRPC channels by norgestimate had minor effects on contractile parameters although resting - tone was lowered. In contrast, selectiveTRPV4 activation led to GKCa activation, which in turn hyperpolarized the myometrial cell membrane, inactivating Ca2+ channels and efficiently abrogated contractile activity. Collectively, these data suggest that alternative calcium conduct ance may play a physiological role in the modulation of myometrial reactivity prior to delivery. A rapid switch from phasic contractions to quiescence by this new class of tocolytics may potentially be of interest in delaying parturition in preterm labor.