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1.
Nat Commun ; 11(1): 4683, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943621

RESUMO

Wearable dry electrodes are needed for long-term biopotential recordings but are limited by their imperfect compliance with the skin, especially during body movements and sweat secretions, resulting in high interfacial impedance and motion artifacts. Herein, we report an intrinsically conductive polymer dry electrode with excellent self-adhesiveness, stretchability, and conductivity. It shows much lower skin-contact impedance and noise in static and dynamic measurement than the current dry electrodes and standard gel electrodes, enabling to acquire high-quality electrocardiogram (ECG), electromyogram (EMG) and electroencephalogram (EEG) signals in various conditions such as dry and wet skin and during body movement. Hence, this dry electrode can be used for long-term healthcare monitoring in complex daily conditions. We further investigated the capabilities of this electrode in a clinical setting and realized its ability to detect the arrhythmia features of atrial fibrillation accurately, and quantify muscle activity during deep tendon reflex testing and contraction against resistance.


Assuntos
Condutividade Elétrica , Epiderme , Monitorização Fisiológica/instrumentação , Movimento (Física) , Pele , Artefatos , Impedância Elétrica , Eletrocardiografia/instrumentação , Eletrocardiografia/métodos , Eletrodos , Eletroencefalografia/instrumentação , Eletroencefalografia/métodos , Eletromiografia/instrumentação , Eletromiografia/métodos , Desenho de Equipamento , Humanos , Monitorização Fisiológica/métodos , Polímeros/química , Sorbitol
2.
Zhonghua Yi Xue Za Zhi ; 100(37): 2908-2912, 2020 Oct 13.
Artigo em Chinês | MEDLINE | ID: mdl-32993249

RESUMO

Objective: To investigate the characteristics of modified Oxford grading scale (MOS) and pelvic floor surface electromyography (sEMG) based on Glazer protocol in patients with stress urinary incontinence (SUI), and analyze the correlation between the two methods. Methods: This study was a cross-sectional survey. A total of 212 subjects in May 2019 were enrolled and divided into SUI group (n=61) and non-SUI group (n=151) based on the commonly used 3 incontinence questions (3IQ). MOS test and sEMG parameters were measured by the same rehabilitator. The sEMG parameters included the mean and variation coefficient in the prerest phase, the maximum and relaxation time of 5 rapid contractions, the mean and variability of EMG in 10 s tonic contraction phase, the mean and variability of EMG in 60 s endurance contraction phase, and the mean and variability of EMG in postrest phase. The differences of the above parameters between SUI group and non-SUI group were compared, the logistic regression and Spearman method were used to analyze the correlation between MOS and sEMG parameters. Results: The prevalence of SUI was 28.8%(61/212) in community, body mass index and delivery mode were the risk factors (all P<0.05). The MOS of the SUI group and the non-SUI group were 3 (2,3) and 3 (3,4), respectively, with significant difference (Z=-2.58, P=0.010). Among the sEMG parameters of SUI group and non-SUI group, the maximum values of phasic contractions were 23.12 (13.65, 37.89), 30.68 (20.28, 47.02) µV, the mean of tonic contractions were 14.32 (9.62, 21.49), 17.65 (12.05, 26.35) µV, and the mean of endurance contractions were 12.78(7.88, 18.76), 16.55(11.13, 22.40) µV, respectively, with statistical significance (Z=-2.34, -2.37, -3.20, all P<0.05). The multivariate logistic regression revealed that both the variation coefficient of tonic contractions (OR=157.86, 95%CI: 1.99-12 595.51, P<0.05) and the amplitude of endurance contractions(OR=1.11, 95%CI: 1.03-1.19, P<0.05) were correlated with SUI. The tonic contractions amplitude had the tendency to be related to SUI (OR=0.95, 95%CI: 0.09-1.00, P<0.05). In all subjects, MOS was correlated with the maximum value of rapid contractions, average value of tonic contractions and average value of endurance contractions (r=0.516, 0.503, 0.464, all P<0.05). In SUI group (r=0.510, 0.442, 0.385, all P<0.05), and non-SUI group (r=0.495, 0.524, 0.488, all P<0.05), MOS was correlated with the above parameters. Conclusions: MOS and sEMG based on Glazer protocol indicate that the contractility of pelvic floor muscle decreases in SUI patients. The results of sEMG and MOS are consistent, which can be used for quantitative evaluation of pelvic floor muscle function in SUI patients.


Assuntos
Diafragma da Pelve , Incontinência Urinária por Estresse , Estudos Transversais , Eletromiografia , Feminino , Humanos , Contração Muscular
3.
J Frailty Aging ; 9(4): 191-196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32996555

RESUMO

BACKGROUND: Aging results in adaptations which may affect the control of motor units. OBJECTIVE: We sought to determine if younger and older men recruit motor units at similar force levels. DESIGN: Cross-sectional, between-subjects design. SETTING: Controlled laboratory setting. PARTICIPANTS: Twelve younger (age = 25 ± 3 years) and twelve older (age = 75 ± 8 years) men. MEASUREMENTS: Participants performed isometric contractions of the dominant knee extensors at a force level corresponding to 50% maximal voluntary contraction (MVC). Bipolar surface electromyographic (EMG) signals were detected from the vastus lateralis. A surface EMG signal decomposition algorithm was used to quantify the recruitment threshold of each motor unit, which was defined as the force level corresponding to the first firing. Recruitment thresholds were expressed in both relative (% MVC) and absolute (N) terms. To further understand age-related differences in motor unit control, we examined the mean firing rate versus recruitment threshold relationship at steady force. RESULTS: MVC force was greater in younger men (p = 0.010, d = 1.15). Older men had lower median recruitment thresholds in both absolute (p = 0.005, d = 1.29) and relative (p = 0.001, d = 1.53) terms. The absolute recruitment threshold range was larger for younger men (p = 0.020; d = 1.02), though a smaller difference was noted in relative terms (p = 0.235, d = 0.50). These findings were complimented by a generally flatter slope (p = 0.070; d = 0.78) and lower y-intercept (p = 0.009; d = 1.17) of the mean firing rate versus recruitment threshold relationship in older men. CONCLUSION: Older men tend to recruit more motor units at lower force levels. We speculate that recruitment threshold compression may be a neural adaptation serving to compensate for lower motor unit firing rates and/or denervation and subsequent re-innervation in aged muscle.


Assuntos
Envelhecimento/fisiologia , Músculo Quadríceps/fisiologia , Recrutamento Neurofisiológico/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Eletromiografia , Humanos , Contração Isométrica , Masculino , Adulto Jovem
4.
Nat Commun ; 11(1): 4510, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908143

RESUMO

With human median lifespan extending into the 80s in many developed countries, the societal burden of age-related muscle loss (sarcopenia) is increasing. mTORC1 promotes skeletal muscle hypertrophy, but also drives organismal aging. Here, we address the question of whether mTORC1 activation or suppression is beneficial for skeletal muscle aging. We demonstrate that chronic mTORC1 inhibition with rapamycin is overwhelmingly, but not entirely, positive for aging mouse skeletal muscle, while genetic, muscle fiber-specific activation of mTORC1 is sufficient to induce molecular signatures of sarcopenia. Through integration of comprehensive physiological and extensive gene expression profiling in young and old mice, and following genetic activation or pharmacological inhibition of mTORC1, we establish the phenotypically-backed, mTORC1-focused, multi-muscle gene expression atlas, SarcoAtlas (https://sarcoatlas.scicore.unibas.ch/), as a user-friendly gene discovery tool. We uncover inter-muscle divergence in the primary drivers of sarcopenia and identify the neuromuscular junction as a focal point of mTORC1-driven muscle aging.


Assuntos
Envelhecimento/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fibras Musculares Esqueléticas/patologia , Junção Neuromuscular/patologia , Sarcopenia/patologia , Envelhecimento/efeitos dos fármacos , Animais , Linhagem Celular , Modelos Animais de Doenças , Eletromiografia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Microdissecção e Captura a Laser , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Camundongos , Mioblastos , Junção Neuromuscular/efeitos dos fármacos , Técnicas de Patch-Clamp , RNA-Seq , Sarcopenia/genética , Sarcopenia/fisiopatologia , Sarcopenia/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sirolimo/administração & dosagem
5.
Nat Commun ; 11(1): 4356, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868777

RESUMO

Complex motor commands for human locomotion are generated through the combination of motor modules representable as muscle synergies. Recent data have argued that muscle synergies are inborn or determined early in life, but development of the neuro-musculoskeletal system and acquisition of new skills may demand fine-tuning or reshaping of the early synergies. We seek to understand how locomotor synergies change during development and training by studying the synergies for running in preschoolers and diverse adults from sedentary subjects to elite marathoners, totaling 63 subjects assessed over 100 sessions. During development, synergies are fractionated into units with fewer muscles. As adults train to run, specific synergies coalesce to become merged synergies. Presences of specific synergy-merging patterns correlate with enhanced or reduced running efficiency. Fractionation and merging of muscle synergies may be a mechanism for modifying early motor modules (Nature) to accommodate the changing limb biomechanics and influences from sensorimotor training (Nurture).


Assuntos
Músculo Esquelético/fisiologia , Corrida/fisiologia , Adulto , Fenômenos Biomecânicos , Criança , Pré-Escolar , Eletromiografia , Feminino , Humanos , Locomoção , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/crescimento & desenvolvimento
6.
Praxis (Bern 1994) ; 109(12): 973-978, 2020 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-32933386

RESUMO

Bruxism: Classification, Diagnostics and Treatment Abstract. Bruxism, the grinding or clenching of teeth, is common in the population. Stress, anxiety syndromes and genetic disposition seem to be dominant factors that lead to increased muscle tension. A distinction is made between two circadian manifestations, sleep and wake bruxism. Bruxism is a major risk factor for tooth structure and dentures. The diagnosis is based on a targeted medical history and examination. Sleep bruxism can be demonstrated by electromyography and video recording in the sleep laboratory. The treatment aims to protect the hard tooth substance and preserve the denture using occlusal splints. Relaxation exercises can improve bruxism. Specialized physiotherapy can improve tension, pain and restricted movement. Botulinum toxin treatment reduces the subjective complaints during the period of action.


Assuntos
Bruxismo do Sono , Ansiedade , Eletromiografia , Humanos , Fatores de Risco , Sono , Bruxismo do Sono/diagnóstico , Bruxismo do Sono/terapia
7.
Int Heart J ; 61(5): 1070-1074, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32921673

RESUMO

We report a case of lethal myocarditis and myositis after pembrolizumab treatment for advanced upper urinary tract urothelial carcinoma. A 69-year-old man underwent pembrolizumab therapy as a second-line treatment. He had myalgia and a slightly elevated creatinine kinase (CK) on the day of the second administration of pembrolizumab. Five days later, the patient was admitted with severe fatigue and an abnormal gait. Physical examination revealed reduced muscle reflexes and proximal muscle weakness. An electrocardiogram (ECG) demonstrated a wide QRS complex ventricular rhythm. A marked elevation of cardiac enzymes, including CK, myoglobin, and cardiac troponin I, was detected. Myocardial biopsy revealed inflammatory cell infiltration and the partial impairment of myocardial tissue. The electromyogram was normal, but inflammation in myofibers was noted in a muscle biopsy. Myocarditis and myositis as immune-related adverse events (irAEs) were suspected, and the patient began intravenous steroid therapy and plasma exchange. However, the patient underwent cardiac arrest three days after admission and began extracorporeal membrane oxygenation and intra-aortic balloon pumping therapy. Despite steroid pulse therapy, the patient demonstrated no sign of improvement and subsequently died 17 days after admission. Immune-mediated myocarditis is a rare but fatal irAE of an immune checkpoint inhibitor (ICI). The present case suggests that myositis precedes myocarditis. Therefore, if myositis is suspected, subsequent myocarditis may need attention. In conclusion, we found that myositis and myocarditis developed in a patient with advanced urothelial carcinoma after pembrolizumab treatment. A routine follow-up of CK and cardiac troponin I, as well as an ECG, should be performed to identify any possible ICI-induced myocarditis and myositis quickly.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Carcinoma de Células de Transição/tratamento farmacológico , Neoplasias Renais/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Miocardite/induzido quimicamente , Miosite/induzido quimicamente , Idoso , Carcinoma de Células de Transição/secundário , Creatina Quinase/sangue , Creatina Quinase Forma MB/sangue , Ecocardiografia , Eletromiografia , Oxigenação por Membrana Extracorpórea , Evolução Fatal , Glucocorticoides/uso terapêutico , Parada Cardíaca , Humanos , Balão Intra-Aórtico , Pelve Renal , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Masculino , Músculo Esquelético/patologia , Miocardite/sangue , Miocardite/diagnóstico por imagem , Miocardite/patologia , Miocárdio/patologia , Mioglobina/sangue , Miosite/sangue , Miosite/patologia , Miosite/fisiopatologia , Troca Plasmática , Troponina I/sangue
9.
PLoS One ; 15(8): e0237451, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790748

RESUMO

The serial feature-positive discrimination task requires the subjects to respond differentially to the identical stimulus depending on the temporal context given by a preceding cue stimulus. In the present study, we examined the involvement of the M1 muscarinic acetylcholine receptors using a selective M1 antagonist VU0255035 in the serial feature-positive discrimination task of eyeblink conditioning in mice. In this task, mice received a 2-s light stimulus as the conditional cue 5 or 6 s before the presentation of a 350-ms tone conditioned stimulus (CS) paired with a 100-ms peri-orbital electrical shock (cued trials), while they did not receive the cue before the presentation of the CS alone (non-cued trials). Each day mice randomly received 30 cued and 30 non-cued trials. We found that VU0255035 impaired acquisition of the conditional discrimination as well as the overall acquisition of the conditioned response (CR) and diminished the difference in onset latency of the CR between the cued and non-cued trials. VU0255035 administration to the control mice after sufficient learning did not impair the pre-acquired conditional discrimination or the CR expression itself. These effects of VU0255035 were almost similar to those with the scopolamine in our previous study, suggesting that among the several types of muscarinic acetylcholine receptors, the M1 receptors may play an important role in the acquisition of the conditional discrimination memory but not in mediating the discrimination itself after the memory had formed in the eyeblink serial feature-positive discrimination learning.


Assuntos
Piscadela/efeitos dos fármacos , Aprendizagem por Discriminação/efeitos dos fármacos , Receptor Muscarínico M1/metabolismo , Sulfonamidas/farmacologia , Tiadiazóis/farmacologia , Animais , Condicionamento Palpebral/efeitos dos fármacos , Condicionamento Palpebral/fisiologia , Eletromiografia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estimulação Luminosa , Receptor Muscarínico M1/antagonistas & inibidores
11.
J. Hum. Growth Dev. (Impr.) ; 30(2): 216-226, May-Aug. 2020. ilus, tab
Artigo em Inglês | LILACS, Index Psicologia - Periódicos técnico-científicos | ID: biblio-1114930

RESUMO

INTRODUCTION: Cerebral Palsy is the most common physical disability in childhood. Physical therapy plays a central role in managing the treatment of disease sequelae. However, it is always a challenge to quantify the results obtained in physical therapy interventions. Thus, surface electromyography has been increasingly used by physiotherapists because it is a quantitative method of evaluation and treatment of neuromuscular system dysfunctionsOBJECTIVE: To analyze the use of surface electromyography as a physical therapy outcome measure in children with cerebral palsyMETHODS: From the search in two important databases, clinical trials of physical therapy interventions that used surface electromyography as a physiotherapy outcome factor in children with cerebral palsy, published in Portuguese, English, French or Spanish until August 2019, were selectedRESULTS: A total of 166 articles were found in the databases searched. Of these, only 15 were included and classified with good methodological quality by PEDro and because they were related to surface electromyography. A flowchart with standardization of actions was built taking into account the most prevalent findings in the studiesCONCLUSION: Surface electromyography has been applied by physiotherapists to evaluate the effects of the intervention, but it is necessary to improve its level of evidence


INTRODUÇÃO: A Paralisia Cerebral é a deficiência física mais comum na infância. A fisioterapia desempenha um papel central na gestão do tratamento das sequelas da Paralisia Cerebral. Contudo, é sempre um desafio conseguir quantificar os resultados obtidos nas intervenções fisioterapêuticas. Dessa forma, a eletromiografia de superfície vem sendo cada vez mais empregada por fisioterapeutas por ser um método quantitativo de avaliação e tratamento das disfunções do sistema neuromuscularOBJETIVO: Analisar o uso da eletromiografia de superfície como medida de desfecho da fisioterapia em crianças com paralisia cerebralMÉTODO: A partir da busca em duas importantes bases de dados, foram selecionados ensaios clínicos de intervenções fisioterapêuticas que utilizaram a eletromiografia de superfície como fator de desfecho da fisioterapia em crianças com paralisia cerebral, publicados em português, inglês, francês ou espanhol até agosto de 2019RESULTADOS: Foram encontrados 166 artigos nas bases consultadas. Desses, somente 15 foram incluídos e classificados com qualidade metodológica boa pelo PEDro e por terem relação com a eletromiografia de superfície. Um fluxograma com padronização das ações foi construído levando em consideração os achados mais prevalentes nos estudosCONCLUSÃO: A eletromiografia de superfície vem sendo aplicada pelos fisioterapeutas para avaliar os efeitos da intervenção, mas precisa melhorar seu nível de evidência


Assuntos
Humanos , Masculino , Feminino , Criança , Paralisia Cerebral , Fisioterapia , Eletromiografia
12.
Medicine (Baltimore) ; 99(34): e21889, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846850

RESUMO

Electromyographic biofeedback (EMG-BF) therapy provides information on the state of contraction of the targeted muscles and relaxation of their antagonists, which can facilitate early active range of motion (RoM) after elbow surgery. Our aim in this study was to calculate the minimum detectable change (MDC) during EMG-BF therapy, initiated in the early postoperative period after elbow surgery.This study is an observational case series. EMG-BF of muscle contraction and relaxation was provided during active elbow flexion and extension exercises. Patients completed 3 sets of 10 trials each of flexion and extension over 4 weeks. The total range of flexion-extension motion and scores on the Japanese Society for Surgery of the Hand version of the disability of the arm, shoulder, and hand questionnaire and the Japanese version of the Patient-Rated Elbow Evaluation were obtained at baseline and weekly during the 4-week intervention period. A prediction formula was developed from the time-series data obtained during the intervention period, using the least-squares method. The estimated value was calculated by removing the slope from the prediction formula and adding the initial scores to residuals between the measured scores and predicted scores individually. Systematic error, MDC at the 95th percentile cutoff (MDC95), repeatability of the measures, and the change from the baseline to each time-point of intervention were assessed.The MDC95 was obtained for all 3 outcome measures and the range of values was as follows: RoM, 8.3° to 22.5°; Japanese version of the Patient-Rated Elbow Evaluation score, 17.6 to 30.6 points; and disability of the arm, shoulder, and hand questionnaire subscale: disability and symptoms score, 14.2 to 22.9 points.The efficacy of EMG-BF after elbow surgery was reflected in earlier initiation of elbow RoM after surgery and improvement in patient-reported upper limb function scores. The calculated MDC95 cut-offs could be used as reference values to assess the therapeutic effects of EMG-BF in individuals.


Assuntos
Biorretroalimentação Psicológica/métodos , Cotovelo/cirurgia , Amplitude de Movimento Articular/fisiologia , Reabilitação/métodos , Adulto , Idoso , Avaliação da Deficiência , Cotovelo/patologia , Eletromiografia , Terapia por Exercício/métodos , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Relaxamento Muscular/fisiologia , Medidas de Resultados Relatados pelo Paciente , Período Pós-Operatório , Reabilitação/tendências , Reprodutibilidade dos Testes , Inquéritos e Questionários , Resultado do Tratamento
13.
PLoS One ; 15(8): e0236497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785230

RESUMO

When human movement is assisted or controlled with a muscle actuator, such as electrical muscle stimulation, a critical issue is the integration of such induced movement with the person's motion intention and how this movement then affects their motor control. Towards achieving optimal integration and reducing feelings of artificiality and enforcement, we explored perceptual simultaneity through electrical muscle stimulation, which involved changing the interval between intentional and induced movements. We report on two experiments in which we evaluated the ranges between detection and stimulus for perceptual simultaneity achievable with an electromyography-triggered electrical muscle stimulation system. We found that the peak range was approximately 80-160 ms, with the timing of perceptual simultaneity shifting according to different adaptation states. Our results indicate that perceptual simultaneity is controllable using this adaptation strategy.


Assuntos
Eletromiografia , Córtex Motor/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Adulto , Estimulação Elétrica , Mãos/fisiologia , Humanos , Masculino , Córtex Motor/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Visão Ocular/fisiologia , Adulto Jovem
14.
Georgian Med News ; (303): 55-58, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32841181

RESUMO

Type of breathing (nasal, oral, oronasal) can turn out to be a causative factor for (or result of) orthodontic anomalies alongside the respiratory-metabolic disorders. Consequently, assessment of functional characteristics of the masticatory apparatus, which differ in oral and nasal breathing modes, could be of interest for the evaluation of the degree of orthodontic dysfunction and formation of an effective individualized treatment plan. Aim of the study was to assess electrophysiologic characteristics of the masticatory muscles bilaterally in nasal and oral breathing modes. The study was conducted on the group of 22 women-volunteers aged 18-30 years. All subjects enrolled in the study had permanent dentition with all second molars present; minimum 28 natural teeth in total. None of them had clinical manifestations of somatic, neurological or endocrine disorders or those of nasal cavity, paranasal sinus or tonsillar disorders.Written informed consent was obtained from all subjects. To narrow the selection of patients eligible for the study, we applied a protocol of normalized electromyographic recording during maximal voluntary contraction of clenching on a cotton roll. Indicators of the degree of mean muscle contractility recorded as a result of standardized maximal voluntary contraction show that in nasal breathing muscle activity is homogenous and symmetric in the right and left masseter and temporalis muscles. Conversely, the indicators are dissociated in oral breathing. Electrophysiological activity and, consequently, contractility of the muscles are reduced, which must be caused by recruitment of decreasing number of less excitable motor units. The results yielded by the study suggest that the data on the state of neuromuscular balance of the masticatory apparatus could be utilized for the assessment of the degree of orthodontic dysfunction and for development of individualized treatment plan.


Assuntos
Músculos da Mastigação , Músculo Temporal , Adolescente , Adulto , Eletromiografia , Feminino , Humanos , Músculo Masseter , Contração Muscular , Adulto Jovem
15.
Codas ; 32(4): e20180285, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32756852

RESUMO

PURPOSE: To compare the impact of isokinetic exercise (tongue suction on the palate) in the cervical region of Class I and Class II / 2nd Division participants, considering the average and the symmetry of Root Means Square (RMS) of suprahyoid and suboccipital muscles and cervical sensory reports. METHOD: 11 participants Class I and 19 Class II / 2nd Division, both genders, mean age 33.4 ± 14.1 years. For the analysis of RMS average and symmetry, electromyography was performed in the suboccipital and suprahyoid muscles, bilaterally, at rest and suction of water in the initial, intermediate and final phases. The cervical sensation was evaluated qualitatively during the exercises. RESULTS: the mean RMS did not differ between Classes (p=0.7), but showed an increase in the intermediate phase in the suboccipital musculature (p=0.0001) and decrease in the suprahyoid musculature. In symmetry, the suprahyoid musculature showed a significant difference between classes (p=0.0001) during the intermediate phase. In the Class I participant the symmetry was reestablished in the final phase, a fact that did not occur in Class II / 2nd Division. Regarding the cervical sensation, only the Class II / 2nd Division had expressive complaints. CONCLUSION: The Isokinetic suctioning exercise of the tongue against the palate, had an expressive repercussion with reports of discomfort and neck pain in the Class II / 2nd Division participants. On average RMS, there was no difference between the classes, but in the intermediate phase, the suboccipital muscles showed a significant increase in the activity. Symmetry in the suprahyoid musculature had a significant difference between the classes and asymmetry in the intermediate phase.


Assuntos
Exercício Físico , Músculos do Pescoço/fisiologia , Língua , Adulto , Eletromiografia , Terapia por Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Treinamento de Resistência/métodos , Língua/fisiologia , Língua/fisiopatologia , Adulto Jovem
16.
Wiad Lek ; 73(7): 1345-1349, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32759417

RESUMO

OBJECTIVE: The aim: To study possibilities of prognosis of pathological wear of tooth hard tissues development depending on the functional activity of masticatory muscles. PATIENTS AND METHODS: Materials and methods: In order to achieve the goal of the study, a survey of patients at the age of 19 to 69 years was conducted for precision of number of persons who have increased tooth wear. During the examination of all patients, three groups were selected: control and two researched ones. Patients in the control group (30 patients between the age of 18 and 60 years old) had an intact dentition without any visible sign of increased tooth wear. The researched groups included 25 patients aged from 18 to 60 years old. The secondresearch group included patients who had increased tooth wear of I-III level. The children of the patients of the II group with or without any sign of increased tooth wear were referred to the third research group. RESULTS: Results: The method of electromyography was performed for the study of peculiarities of the muscular activity of the maxillofacial area of the patients of the control and research groups. In our opinion, all manifestations of increased tooth wear are related to changes in the muscle system, the motor apparatus and the nervous activity of an organism. CONCLUSION: Conclusions: The study of direct muscular apparatus and related bone system may predict the possibility of developing of an increased tooth wear of young patients in the future and prevent its development, as well as to justify the application of a prevention and treatment plan of the studied pathology.


Assuntos
Desgaste dos Dentes , Adolescente , Adulto , Eletromiografia , Humanos , Músculos da Mastigação , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
17.
Indian J Dent Res ; 31(3): 363-367, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32769268

RESUMO

Aim: This study describes the relationship of the chronophysiological organization of the lateral teeth occlusion and the parameters of the chewing unit of the human dentofacial system (bioelectric potentials, the force of the masticatory muscles, masticatory efficiency) which should be considered in modeling of prosthesis occlusal surfaces. Materials and Methods: Examination of 200 respondents with a "day" chronotype, with Angle class I bilateral occlusion at the age of 18-35 years was conducted daily for 3 days. From 8.00 to 20.00, every 4 hours, the amplitude of the electromyography, the jaw muscles' force, the masticatory efficiency, the area of the occlusal contacts, and the near-contact zones were determined. Results: The activity of the masticatory muscles increased during the period from 12.00 to 16.00, which coincided with the escalation of the masticatory efficiency and of the occlusal contacts area. The relationship between the occlusal surfaces' relief and masticatory efficiency is described by two types of occlusal surfaces' topography - smoothed and pronounced, differing by the ratio of the areas of the occlusal contacts and the near-contact zones in 0.25- and 1-mm wide. Conclusion: The modeling of the occlusal surface of the permanent prosthetic restorations for patients with the "day" chronotype should be carried out with the area values of occlusal contacts and near-contact zones corresponding to the period of masticatory muscles activity from 12.00 to 16.00 and in accordance with the characteristic type of the occlusal surfaces' relief.


Assuntos
Oclusão Dentária , Má Oclusão de Angle Classe I , Eletromiografia , Humanos , Mastigação , Músculos da Mastigação
18.
Ideggyogy Sz ; 73(7-08): 249-252, 2020 Jul 30.
Artigo em Húngaro | MEDLINE | ID: mdl-32750241

RESUMO

Objective - Conflicting theoretical models exist regarding the mechanism related to the ability of the Jendrassik maneuver to reinforce reflex parameters. Our objective was to investigate if vigorous handgrip would induce changes in recurrent inhibition of soleus motoneurons. Method - Soleus H reflex was evoked by stimulating the tibial nerve at rest and during bilateral vigorous handgrip, alternating single (H1) and paired stimulation (H2). At paired stimulation we used interstimulus intervals of 10, 15, 20 and 25 ms and supramaximal test stimulus. H1- and H2-wave amplitudes were expressed as percentage of maximal M-wave amplitude. Conditioned H2 wave maximal (H2max) and minimal (H2) amplitudes evoked at rest and expressed as a percentage of the unconditioned H1max amplitude were compared with the corresponding values obtained during handgrip by means of paired Student test and Bonferroni correction. Subjects - At the study participated 28 healthy volunteers. Results - The H1max/Mmax × 100 values obtained during handgrip (37.5±10.1) were significantly higher than those obtained at rest (27.1±7.4). The H2max/H1max × 100-va-lues obtained at paired stimulation were significantly higher during handgrip than at rest, while no significant diffe-rence was found between the H2/H1max × 100-values obtained during handgrip and at rest respectively. Discussion - The H2max/H1max is determined by both the excitability of the motoneurons and the recurrent inhibition elicited by the conditioning stimulus, while H2/H1max indicates only the level of recurrent inhibition. According to our results the Renshaw cells retain their inhibitory effect on the soleus alpha motoneurons during remote muscle contraction. Conclusion - Soleus H reflex enhancement during Jendrassik maneuver is not due to decrease of recurrent inhibition.


Assuntos
Antebraço/fisiologia , Reflexo H , Força da Mão , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia , Reflexo H/fisiologia , Humanos , Músculos/inervação , Nervo Tibial/fisiologia
20.
PLoS One ; 15(7): e0236254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687520

RESUMO

Muscle activity changes quantitatively and temporally during the motor learning process. However, the association between variability in muscle electrical activity and the learning and performance of dexterous hand movements is not well understood. Therefore, we undertook this study to investigate the relationships between temporal and quantitative variabilities in muscle activity and the learning of motor skills. Thirty-eight healthy participants performed 30 trials of a task that measured the time taken to rotate two cork balls 20 times using their non-dominant hand. The electromyographic (EMG) activities of the abductor pollicis brevis (APB), first dorsal interosseous, and extensor digitorum (ED) muscles were recorded. Temporal and quantitative variabilities in the EMG activity were evaluated by calculating the coefficient of variation of the duration and area of EMG activation. As motor learning proceeded, the task was completed more quickly and the EMG variability decreased. For all three muscles, significant correlations were observed between individual participants' ball rotation time and EMG variability. Furthermore, significant positive correlations were observed between improvement in ball rotation time and reduction in EMG variability for the APB and ED muscles. These novel findings provide important insights regarding the relationships between temporal and quantitative variabilities in muscle activity and the learning of fine motor skills.


Assuntos
Variação Biológica Individual , Mãos/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia , Feminino , Humanos , Masculino , Movimento/fisiologia , Contração Muscular/fisiologia , Fatores de Tempo , Adulto Jovem
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