60,767 results match your criteria contractile activity


Using optogenetics to link myosin patterns to contractile cell behaviors during convergent extension.

Biophys J 2021 Jul 19. Epub 2021 Jul 19.

Department of Mechanical Engineering, Columbia University, New York, New York, 10027, USA. Electronic address:

Distinct patterns of actomyosin contractility are often associated with particular epithelial tissue shape changes during development. For example, a planar polarized pattern of myosin II localization regulated by Rho1 signaling during Drosophila body axis elongation is thought to drive cell behaviors that contribute to convergent extension. However, it is not well understood how specific aspects of a myosin pattern influence the multiple cell behaviors-including cell intercalation, cell shape changes, and apical cell area fluctuations-that simultaneously occur during morphogenesis. Read More

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Diacylglycerol Kinase Inhibition Reduces Airway Contraction by Negative Feedback Regulation of Gq-signaling.

Am J Respir Cell Mol Biol 2021 Jul 22. Epub 2021 Jul 22.

Thomas Jefferson University, 6559, Center for Translational Medicine, Philadelphia, Pennsylvania, United States;

Exaggerated airway smooth muscle (ASM) contraction regulated by the Gq family of G protein-coupled receptors (GPCRs) causes airway hyperresponsiveness (AHR) in asthma. Activation of Gq-coupled GPCRs leads to phospholipase C (PLC)-mediated generation of inositol triphosphate (IP3) and diacylglycerol (DAG). DAG signaling is terminated by the action of DAG kinase (DGK) that converts DAG into phosphatidic acid (PA). Read More

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Overload of anxiety on postural control impairments in chronic stroke survivors: The role of external focus and cognitive task on the automaticity of postural control.

PLoS One 2021 22;16(7):e0252131. Epub 2021 Jul 22.

Department of Neurosciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences (TUMS), Tehran, Iran.

Background: Despite the high prevalence of anxiety among chronic stroke survivors and evidence of its negative effects on postural control in healthy subjects, it is unclear whether anxiety also affects postural control in these patients. Recent evidence of improved postural control of healthy subjects by distracting the attention using an external focus (EF) or cognitive task, raises the question of whether similar benefits would be observed in stroke survivors. Thus, the current study aimed to investigate the effects of anxiety and distracting the attention on postural control of chronic stroke survivors in terms of both postural sway measures and neuromuscular regulation. Read More

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Effects of diaphragmatic control on multiparametric analysis of the sniff nasal inspiratory pressure test and inspiratory muscle activity in healthy subjects.

PLoS One 2021 22;16(7):e0253132. Epub 2021 Jul 22.

PneumoCardioVascular Lab/HUOL, Hospital Universitário Onofre Lopes, Empresa Brasileira de Serviços Hospitalares and Departamento de Fisioterapia Universidade Federal do Rio Grande do Norte, Natal, Brazil.

Background: We investigated the influence of diaphragmatic activation control (diaphC) on the relaxation rate, contractile properties and electrical activity of the inspiratory muscles of healthy subjects. Assessments were performed non-invasively using the sniff inspiratory pressure test (SNIP) and surface electromyography, respectively.

Methods: Twenty-two subjects (10 men and 12 women) performed 10 sniff maneuvers in two different days: with and without diaphC instructions. Read More

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Changes in neural drive to calf muscles during steady submaximal contractions after repeated static stretches.

J Physiol 2021 Jul 22. Epub 2021 Jul 22.

Department of Integrative Physiology, University of Colorado, Boulder, CO, United States.

Key Points: Repeated static-stretching interventions consistently increase the range of motion about a joint and decrease total joint stiffness, but findings on the changes in muscle and connective-tissue properties are mixed. The influence of these stretch-induced changes on muscle function at submaximal forces is unknown. To address this gap in knowledge, we estimated the changes in neural drive to the plantar flexor muscles after a static-stretch intervention. Read More

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Myogenic tremor - a novel tremor entity.

Curr Opin Neurol 2021 Jul 20. Epub 2021 Jul 20.

Department of Neurology, Uniklinikum C.G.Carus, Dresden, Germany Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke/NIH, Porter Neuroscience Research Center, Bethesda, Maryland, USA.

Purpose Of Review: Tremor is a common neurological symptom with a plethora of potential etiologies. Apart from physiological tremor, the vast majority of tremor syndromes are linked to a pacemaker in the central nervous system (CNS) or, less common, in the peripheral nervous system. Myogenic tremor is a novel tremor entity, first reported in 2019 and believed to originate in the muscle itself. Read More

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Ankyrin-dependent Na channel clustering prevents neuromuscular synapse fatigue.

Curr Biol 2021 Jul 10. Epub 2021 Jul 10.

Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA. Electronic address:

Skeletal muscle contraction depends on activation of clustered acetylcholine receptors (AchRs) and muscle-specific Na channels (Nav1.4). Some Nav1. Read More

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Single-Component Optogenetic Tools for Inducible RhoA GTPase Signaling.

Adv Biol (Weinh) 2021 Jul 21:e2100810. Epub 2021 Jul 21.

Department of Bioengineering, University of Pennsylvania, 210 South 33 rd Street, Philadelphia, PA, 19104, USA.

Optogenetic tools are created to control RhoA GTPase, a central regulator of actin organization and actomyosin contractility. RhoA GTPase, or its upstream activator ARHGEF11, is fused to BcLOV4, a photoreceptor that can be dynamically recruited to the plasma membrane by a light-regulated protein-lipid electrostatic interaction with the inner leaflet. Direct membrane recruitment of these proteins induces potent contractile signaling sufficient to separate adherens junctions with as little as one pulse of blue light. Read More

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Identification of a novel distension-evoked motility pattern in the mouse uterus.

Am J Physiol Regul Integr Comp Physiol 2021 07 21. Epub 2021 Jul 21.

College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia.

The dynamic changes in uterine contractility in response to distension are incompletely understood. Rhythmic, propagating contractions of non-pregnant uterine smooth muscle occur in the absence of nerve activity (i.e. Read More

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Atlas of voluntary facial muscle activation: Visualization of surface electromyographic activities of facial muscles during mimic exercises.

PLoS One 2021 19;16(7):e0254932. Epub 2021 Jul 19.

Department of Otolaryngology, Jena University Hospital, Friedrich-Schiller-University Jena, Jena, Germany.

Complex facial muscle movements are essential for many motoric and emotional functions. Facial muscles are unique in the musculoskeletal system as they are interwoven, so that the contraction of one muscle influences the contractility characteristic of other mimic muscles. The facial muscles act more as a whole than as single facial muscle movements. Read More

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LFA-1 and Kindlin-3 enable the collaborative transport of SLP-76 microclusters by myosin and dynein motors.

J Cell Sci 2021 Jul 19. Epub 2021 Jul 19.

Department of Immunology, Tufts University School of Medicine, Boston, MA 02111, USA.

Integrin engagement within the immune synapse enhances T cell activation, but our understanding of this process is incomplete. In response to T cell receptor (TCR) ligation, SLP-76 (LCP2), ADAP (FYB), and SKAP-55 (SKAP1) are recruited into microclusters and activate integrins via the effectors Talin-1 and Kindlin-3. We postulated that integrins influence the centripetal transport and signaling of SLP-76 microclusters via these linkages. Read More

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Rehabilitation Exercises for Dysfunction of the Scapula: Exploration of Muscle Activity Using Fine-Wire EMG.

Am J Sports Med 2021 Jul 19:3635465211025002. Epub 2021 Jul 19.

Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium.

Background: Scapular muscle activity during shoulder exercises has been explored with surface electromyography (EMG). However, knowledge about the activity of deeper-layer scapular muscles is still limited.

Purpose: To investigate EMG activation of the deeper-layer scapular stabilizers (levator scapulae [LS], rhomboid major [RM], pectoralis minor [Pm] muscles) together with superficial muscle activity (upper [UT], middle [MT], and lower trapezius [LT] and serratus anterior [SA]) during 4 exercises often used for training scapular function. Read More

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Antispasmodic activity and mechanism of action of polyherbal formulation DCD-684 on rabbit jejunum.

Pak J Pharm Sci 2021 Mar;34(2(Supplementary)):711-722

Medics Laboratories (Pvt.) Limited, DP 32, Sector 12C, North Karachi Industrial Area Karachi, Pakistan.

Digas colic drops (DCD-684) is a polyherbal formulation containing decoctions of five medicinal plants namely Carum carvi L., Foeniculum vulgare Mill, Mentha arvensis L., Mentha piperita L. Read More

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Similar improvements in cognitive inhibitory control following low-intensity resistance exercise with slow movement and tonic force generation and high-intensity resistance exercise in healthy young adults: a preliminary study.

J Physiol Sci 2021 Jul 17;71(1):22. Epub 2021 Jul 17.

Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.

This study compared the effects of low-intensity resistance exercise with slow movement and tonic force generation (ST-LRE) and high-intensity resistance exercise (HRE) on post-exercise improvements in cognitive inhibitory control (IC). Sixteen young males completed ST-LRE and HRE sessions in a crossover design. Bilateral knee extensor ST-LRE and HRE (8 repetitions/set, 6 sets) were performed with 50% of one-repetition maximum with slow contractile speed and 80% of one-repetition maximum with normal contractile speed, respectively. Read More

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The impact of radiation therapy on vaginal biomechanical properties.

Eur J Obstet Gynecol Reprod Biol 2021 Jul 1;264:36-40. Epub 2021 Jul 1.

Department of Obstetrics and Gynecology, Rambam Health Care Campus, and Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel. Electronic address:

Objective: In women with cervical cancer (CC), treatment with radiation causes changes in vaginal biomechanical properties, anatomy and function. The aims of the current study were to objectively assess effects of radiotherapy (RT) on vaginal elasticity, wall mobility and contraction strength; and to evaluate associations of these changes with sexual function.

Study Design: This prospective cohort study was approved by our Institutional Review Board. Read More

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Deletion of BK channels decreased skeletal and cardiac muscle function but increased smooth muscle contraction in rats.

Biochem Biophys Res Commun 2021 Jul 13;570:8-14. Epub 2021 Jul 13.

Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, China; Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Disease, Beijing, 100069, China. Electronic address:

Large conductance calcium-activated potassium channel (BK channel) is widely expressed in skeletal muscle, myocardium, smooth muscle and other muscle tissues. Mutation, abnormal expression and altered activity of BK channel are linked to muscle-related diseases such as dyskinesia, epilepsy and erectile dysfunction. In order to compare the effects of BK channel on different muscle tissues, we constructed BK channel gene knockout rats‌‌‌‌‍‍‍ (BK rats). Read More

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Characterization and genome analysis of novel Klebsiella phage BUCT556A with lytic activity against carbapenemase-producing Klebsiella pneumoniae.

Virus Res 2021 Jul 13;303:198506. Epub 2021 Jul 13.

College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address:

Carbapenem-resistant Klebsiella pneumoniae (CRKP) have spread globally and led to the limited choice of antimicrobial treatment of K. pneumoniae-induced infections. Bacteriophages are considered as an effective strategy against bacterial infections. Read More

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Quercetin affects uterine smooth muscle contractile activity in gilts.

PLoS One 2021 16;16(7):e0252438. Epub 2021 Jul 16.

Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland.

Quercetin is a polyphenolic flavonoid occurring in leaves, stems, flowers and fruits of many plants. In traditional Chinese medicine, it is used as a natural therapeutic agent with a broad spectrum of activities (antioxidant, neuroprotective, anti-inflammatory, anticancer, antibacterial and antiviral). Moreover, quercetin affects function of the reproductive tract, however the knowledge of this activity is still fragmentary. Read More

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Voltage-Gated Potassium Channel Dysfunction in Dorsal Root Ganglia Contributes to the Exaggerated Exercise Pressor Reflex in Rats with Chronic Heart Failure.

Am J Physiol Heart Circ Physiol 2021 Jul 16. Epub 2021 Jul 16.

Department of Anesthesiology, grid.266813.8University of Nebraska Medical Center, Omaha, NE, United States.

An exaggerated exercise pressor reflex (EPR) causes excessive sympatho-excitation and exercise intolerance during physical activity in the chronic heart failure (CHF) state. Muscle afferent sensitization contributes to the genesis of the exaggerated EPR in CHF. However, the cellular mechanisms underlying muscle afferent sensitization in CHF remain unclear. Read More

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The Ergoreflex: how the Skeletal Muscle Modulates Ventilation and Cardiovascular Function in Health and Disease.

Eur J Heart Fail 2021 Jul 16. Epub 2021 Jul 16.

Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy.

The control of ventilation and cardiovascular function during physical activity is partially regulated by the ergoreflex, a cardiorespiratory reflex activated by physical activity. Two components of the ergoreflex have been identified: the mechanoreflex, which is activated early by muscle contraction and tendon stretch, and the metaboreflex, which responds to the accumulation of metabolites in the exercising muscles. Patients with heart failure (HF) often develop a skeletal myopathy with varying degrees of severity, from a subclinical disease to cardiac cachexia. Read More

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Bimodal Effects of P2Y Antagonism on Matrix Metalloproteinase-Associated Contractile Dysfunction in İnsulin-Resistant Mammalian Heart.

Biol Trace Elem Res 2021 Jul 16. Epub 2021 Jul 16.

Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey.

The matrix metalloproteinases (MMPs) contribute to matrix remodeling in diabetes via tissue degradation; however, their contributions can be different depending on the pathology. For instance, MMPs are elevated in acute stress hyperglycemia, whereas they can be degraded in chronic hyperglycemia. Since studies emphasize the possible cardioprotective effect of ticagrelor (Tica) beyond its antiplatelet action, we aimed to examine whether Tica treatment can reverse the depressed heart function of metabolic syndrome (MetS) rats via affecting the expression levels of MMPs. Read More

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Specific amino acid supplementation rescues the heart from lipid overload-induced insulin resistance and contractile dysfunction by targeting the endosomal mTOR-v-ATPase axis.

Mol Metab 2021 Jul 12:101293. Epub 2021 Jul 12.

Departments of Genetics & Cell Biology and, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands; Departments of Clinical Genetics, Maastricht University Medical Center+, Maastricht, The Netherlands. Electronic address:

Objective: The diabetic heart is characterized by extensive lipid accumulation which often leads to cardiac contractile dysfunction. The underlying mechanism involves a pivotal role for vacuolar-type H-ATPase (v-ATPase, functioning as endosomal/lysosomal proton pump). Specifically, lipid oversupply to the heart causes disassembly of v-ATPase and endosomal de-acidification. Read More

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Physical Activity Engagement Worsens Health Outcomes and Limits Exercise Capacity in Growth-restricted Mice.

Med Sci Sports Exerc 2021 Aug;53(8):1561-1571

Department of Kinesiology, Michigan State University, East Lansing, MI.

Introduction: A total of 161 million children a year are growth restricted, leading to a 47% increased risk of chronic disease in adulthood. Physical activity (PA) reduces the risk of mortality from chronic disease. The purpose of the present investigation was to determine the effect of a PA intervention (wheel running) on cardiac and skeletal muscle capacities in gestational (GUN) and postnatal (PUN) growth-restricted mice as compared with nonrestricted controls (CON). Read More

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Molecular and cellular basis of genetically inherited skeletal muscle disorders.

Nat Rev Mol Cell Biol 2021 Jul 13. Epub 2021 Jul 13.

Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.

Neuromuscular disorders comprise a diverse group of human inborn diseases that arise from defects in the structure and/or function of the muscle tissue - encompassing the muscle cells (myofibres) themselves and their extracellular matrix - or muscle fibre innervation. Since the identification in 1987 of the first genetic lesion associated with a neuromuscular disorder - mutations in dystrophin as an underlying cause of Duchenne muscular dystrophy - the field has made tremendous progress in understanding the genetic basis of these diseases, with pathogenic variants in more than 500 genes now identified as underlying causes of neuromuscular disorders. The subset of neuromuscular disorders that affect skeletal muscle are referred to as myopathies or muscular dystrophies, and are due to variants in genes encoding muscle proteins. Read More

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The mitochondrial calcium homeostasis orchestra plays its symphony: Skeletal muscle is the guest of honor.

Int Rev Cell Mol Biol 2021 20;362:209-259. Epub 2021 May 20.

Department of Biomedical Sciences, University of Padua, Padua, Italy. Electronic address:

Skeletal muscle mitochondria are placed in close proximity of the sarcoplasmic reticulum (SR), the main intracellular Ca store. During muscle activity, excitation of sarcolemma and of T-tubule triggers the release of Ca from the SR initiating myofiber contraction. The rise in cytosolic Ca determines the opening of the mitochondrial calcium uniporter (MCU), the highly selective channel of the inner mitochondrial membrane (IMM), causing a robust increase in mitochondrial Ca uptake. Read More

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Mechanisms of Lower Extremity Vein Dysfunction in Chronic Venous Disease and Implications in Management of Varicose Veins.

Vessel Plus 2021 29;5. Epub 2021 May 29.

Vascular Surgery Research Laboratories, Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA.

Chronic venous disease (CVD) is a common venous disorder of the lower extremities. CVD can be manifested as varicose veins (VVs), with dilated and tortuous veins, dysfunctional valves and venous reflux. If not adequately treated, VVs could progress to chronic venous insufficiency (CVI) and lead to venous leg ulcer (VLU). Read More

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Cardiomyocyte Proliferative Capacity Is Restricted in Mice With Mutation.

Front Cardiovasc Med 2021 23;8:639148. Epub 2021 Jun 23.

Department of Cardiovascular Medicine, Nara Medical University, Kashihara, Japan.

is one of the leading causative genes of genetically inherited dilated cardiomyopathy (DCM). Unlike most DCM-causative genes, which encode sarcomeric or sarcomere-related proteins, encodes nuclear envelope proteins, lamin A and C, and does not directly associate with contractile function. However, a mutation in this gene could lead to the development of DCM. Read More

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Overexpressing miR-122-5p Inhibits the Relaxation of Vaginal Smooth Muscle in Female Sexual Arousal Disorder by Targeting Vasoactive Intestinal Peptide Receptor 1.

Sex Med 2021 Jul 7;9(4):100390. Epub 2021 Jul 7.

School of Nursing, Nanjing Medical University, Jiangsu, China; Women's Hospital of Nanjing Medical University (Nanjing Maternity and Child Health Care Hospital), Nanjing, China. Electronic address:

Introduction: Female sexual arousal disorder (FSAD) is a common issue causing physical and psychological pain, but it has no standard diagnostic criteria or treatment. So its pathogenesis desiderates to be explored.

Aim: To investigate the specific function of miR-122-5p in FSAD. Read More

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Preterm Labor is a Distinct Process from Term Labor following Computational Analysis of Human Myometrium.

Am J Obstet Gynecol 2021 Jul 7. Epub 2021 Jul 7.

Mothers and Babies Research Centre, Hunter Medical Research Institute, Newcastle, NSW, Australia; University of Newcastle, Newcastle, NSW, Australia. Electronic address:

Background: The onset of term human parturition involves myometrial gene expression changes to transform the uterus from a quiescent to a contractile phenotype. It is uncertain whether the same changes occur in the uterus during preterm labor.

Objective: (s): To compare myometrial gene expression between term and preterm labor and determine if the presence of acute clinical chorioamnionitis or twin gestation affects these signatures. Read More

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Global Reach 2018: The adaptive phenotype to life with chronic mountain sickness and polycythaemia.

J Physiol 2021 Jul 10. Epub 2021 Jul 10.

Department of Sport Science, Division of Performance Physiology and Prevention, University of Innsbruck, Innsbruck, Austria.

Key Points: Humans suffering from polycythaemia undergo multiple circulatory adaptations including changes in blood rheology and structural and functional vascular adaptations to maintain normal blood pressure and vascular shear stresses, despite high blood viscosity. During exercise, several circulatory adaptations are observed, especially involving adrenergic and non-adrenergic mechanisms within non-active and active skeletal muscle to maintain exercise capacity, which is not observed in animal models. Despite profound circulatory stress, i. Read More

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