Abnormal Muscle Research Articles

Neonatal X-linked myotubular myopathy with a de novo mutation: A case report and literature review.

X-linked myotubular myopathy (XLMTM) is a rare congenital myopathy. In February 2021, a male neonate was admitted to the West China Second University Hospital, Sichuan University, with clinical manifestations of hypotonia, accompanied by distinctive facial features, and requiring continuous ventilatory support. He was born prematurely at 36+2 weeks gestation and developed respiratory distress postnatally, followed by difficulty in weaning from mechanical ventilation. Additional clinical features included hypotonia of the limbs, swallowing dysfunction, and specific facial characteristics (elongated limbs, narrow face, high-arched palate, wrist drop, empty scrotum, elongated fingers/toes). Genetic testing confirmed the diagnosis of XLMTM. Whole-exome sequencing analysis of the family revealed no mutations in the father, paternal grandfather, or paternal grandmother, while the mother had a heterozygous mutation. The pathogenic mutation was identified as MTM1 gene (OMIM: 300415), chromosome position chrX-150649714, with a nucleotide change of c.868-2A>C. The patient exhibited typical facial features. Genetic testing is crucial for accurate diagnosis of XLMTM in infants presenting with abnormal muscle tone and distinctive facial features.

The utility of electrodiagnostic testing in unprovoked rhabdomyolysis in the era of next-generation sequencing.

Rhabdomyolysis is an etiologically heterogeneous, acute necrosis of myofibers characterized by transient marked creatine kinase (CK) elevation associated with myalgia, muscle edema, and/or weakness. The study aimed to determine the role of electrodiagnostic (EDX) testing relative to genetic testing and muscle biopsy in patients with unprovoked rhabdomyolysis in identifying an underlying myopathy. EDX database was reviewed to identify unprovoked rhabdomyolysis patients who underwent EDX testing between January 2012 and January 2022. Each patient's clinical profile, EDX findings, muscle pathology, laboratory, and genetic testing results were analyzed. Of 66 patients identified, 32 had myopathic electromyography (EMG). Muscle biopsy and genetic testing were performed in 41 and 37 patients, respectively. A definitive diagnosis was achieved in 15 patients (11 myopathic EMG and 4 nonmyopathic EMG; p = .04) based on abnormal muscle biopsy (4/11 patients) or genetic testing (12/12 patients, encompassing 5 patients with normal muscle biopsy and 3 patients with nonmyopathic EMG). These included seven metabolic and eight nonmetabolic myopathies (five muscular dystrophies and three ryanodine receptor 1 [RYR1]-myopathies). Patients were more likely to have baseline weakness (p < .01), elevated baseline CK (p < .01), and nonmetabolic myopathies (p = .03) when myopathic EMG was identified. Myopathic EMG occurred in approximately half of patients with unprovoked rhabdomyolysis, more likely in patients with weakness and elevated CK at baseline. Although patients with myopathic EMG were more likely to have nonmetabolic myopathies, nonmyopathic EMG did not exclude myopathy, and genetic testing was primarily helpful to identify an underlying myopathy. Genetic testing should likely be first-tier diagnostic testing following unprovoked rhabdomyolysis.

The interplay of maternal and offspring obesogenic diets: the impact on offspring metabolism and muscle mitochondria in an outbred mouse model.

Consumption of obesogenic (OB) diets increases the prevalence of maternal obesity worldwide, causing major psychological and social burdens in women. Obesity not only impacts the mother's health and fertility but also elevates the risk of obesity and metabolic disorders in the offspring. Family lifestyle is mostly persistent through generations, possibly contributing to the growing prevalence of obesity. We hypothesized that offspring metabolic health is dependent on both maternal and offspring diet and their interaction. We also hypothesized that the sensitivity of the offspring to the diet may be influenced by the match or mismatch between offspring and maternal diets. To test these hypotheses, outbred Swiss mice were fed a control (C, 10% fat, 7% sugar, and n = 14) or OB diet (60% fat, 20% sugar, and n = 15) for 7 weeks and then mated with the same control males. Mice were maintained on the same corresponding diet during pregnancy and lactation, and the offspring were kept with their mothers until weaning. The study focused only on female offspring, which were equally distributed at weaning and fed C or OB diets for 7 weeks, resulting in four treatment groups: C-born offspring fed C or OB diets (C » C and C » OB) and OB-born offspring fed C or OB diets (OB » C and OB » OB). Adult offspring's systemic blood profile (lipid and glucose metabolism) and muscle mitochondrial features were assessed. We confirmed that the offspring's OB diet majorly impacted the offspring's health by impairing the offspring's serum glucose and lipid profiles, which are associated with abnormal muscle mitochondrial ultrastructure. Contrarily, maternal OB diet was associated with increased expression of mitochondrial complex markers and mitochondrial morphology in offspring muscle, but no additive effects of (increased sensitivity to) an offspring OB diet were observed in pups born to obese mothers. In contrast, their metabolic profile appeared to be healthier compared to those born to lean mothers and fed an OB diet. These results are in line with the thrifty phenotype hypothesis, suggesting that OB-born offspring are better adapted to an environment with high energy availability later in life. Thus, using a murine outbred model, we could not confirm that maternal obesogenic diets contribute to female familial obesity in the following generations.

Quantitative ultrasonography reveals skeletal muscle abnormalities in carriers of DMD pathogenic variants.

Carriers of DMD pathogenic variants may become symptomatic and develop muscle-related manifestations. Despite that, few studies have attempted to characterize changes in the muscles of these carriers using imaging tools, particularly muscle ultrasound (MUS). The aim of this study was to compare lower limb MUS findings in carriers of DMD pathogenic variants (cDMD) vs healthy controls. Twenty-eight women (15 cDMD and 13 controls) underwent clinical evaluation and MUS. We collected information about muscle-related symptoms and assessed muscle strength. MUS was performed by a single physician (blind to the genetic status of subjects). The following muscles were assessed: rectus femoris, sartorius, tibialis anterior, and medial gastrocnemius. For each site, we computed data on muscle thickness, cross-sectional area, sound attenuation index, and elastography. Between-group comparisons were assessed using nonparametric tests and p-values <.05 were deemed significant. None of the subjects had objective muscle weakness, but exercise intolerance/fatigue was reported by four cDMDs and only one control. Regarding MUS, sound attenuation indices were significantly higher among carriers for all muscles tested. Longitudinal and axial deep echo intensities for the rectus femoris and tibialis anterior were also higher in the cDMD group compared with controls. No significant between-group differences were noted for elastography values, muscle area, or mean echo intensities. cDMD have skeletal muscle abnormalities that can be detected using quantitative MUS. Further studies are needed to determine whether such abnormalities are related to muscle symptoms in these patients.

Cardiac output-mediated regulation of cerebral blood flow during exercise: Clinical perspectives on the indirect impact of muscle metaboreflex.

The muscle metaboreflex stimulates the elevation of arterial blood pressure, aiming to rectify the oxygen deficit by enhancing oxygen delivery to support muscle activity. Moreover, activating the muscle metaboreflex significantly increases cardiac output (CO) by increasingfactors such as heart rate, ventricular contractility, preload, stroke volume and mobilization of central blood volume. Previous studies indicate that ageing and cardiovascular diseases modify the muscle metaboreflex during exercise, limiting the ability to increase CO during physical activity. Alongside reduced exercise capacity, the attenuated rise in CO due to abnormal muscle metaboreflex in these patients impedes the increase in cerebral blood flow during exercise. Considering that CO plays a pivotal role in regulating cerebral blood flow adequately during exercise, this occurrence might contribute to an elevated risk of cerebral diseases, and it could also, at least, reduce the effective role of exercise in preventing cerebral disease and dementia among elderly individuals and patients with cardiovascular conditions. Therefore, it is important to consider this phenomenon when optimizing the effectiveness of exercise rehabilitation in patients with cardiovascular disease to prevent cerebral diseases and dementia.

Characterization of sensory and motor dysfunction and morphological alterations in late stages of type 2 diabetic mice.

Diabetic neuropathy is the most common complication of diabetes and lacks effective treatments. Although sensory dysfunction during the early stages of diabetes has been extensively studied in various animal models, the functional and morphological alterations in sensory and motor systems during late stages of diabetes remain largely unexplored. In the current work, we examined the influence of diabetes on sensory and motor function as well as morphological changes in late stages of diabetes. The obese diabetic Leprdb/db mice (db/db) were used for behavioral assessments and subsequent morphological examinations. The db/db mice exhibited severe sensory and motor behavioral defects at the age of 32 weeks, including significantly higher mechanical withdrawal threshold and thermal latency of hindpaws compared with age-matched nondiabetic control animals. The impaired response to noxious stimuli was mainly associated with the remarkable loss of epidermal sensory fibers, particularly CGRP-positive nociceptive fibers. Unexpectedly, the area of CGRP-positive terminals in the spinal dorsal horn was dramatically increased in diabetic mice, which was presumably associated with microglial activation. In addition, the db/db mice showed significantly more foot slips and took longer time during the beam-walking examination compared with controls. Meanwhile, the running duration in the rotarod test was markedly reduced in db/db mice. The observed sensorimotor deficits and motor dysfunction were largely attributed to abnormal sensory feedback and muscle atrophy as well as attenuated neuromuscular transmission in aged diabetic mice. Morphological analysis of neuromuscular junctions (NMJs) demonstrated partial denervation of NMJs and obvious fragmentation of acetylcholine receptors (AChRs). Intrafusal muscle atrophy and abnormal muscle spindle innervation were also detected in db/db mice. Additionally, the number of VGLUT1-positive excitatory boutons on motor neurons was profoundly increased in aged diabetic mice as compared to controls. Nevertheless, inhibitory synaptic inputs onto motor neurons were similar between the two groups. This excitation-inhibition imbalance in synaptic transmission might be implicated in the disturbed locomotion. Collectively, these results suggest that severe sensory and motor deficits are present in late stages of diabetes. This study contributes to our understanding of mechanisms underlying neurological dysfunction during diabetes progression and helps to identify novel therapeutic interventions for patients with diabetic neuropathy.

IMU-Based Approach to Detect Spastic Cerebral Palsy in Infants at Early Stages

INTRODUCTION: Cerebral Palsy (CP) is a non-progressive neurological disorder affecting muscle control in early childhood, leading to permanent alterations in body posture and movement. Early identification is crucial for accurate diagnosis and therapy-based interventions. In recent years, an automated monitoring system has been developed to facilitate the health assessment of infants, enabling early recognition of neurological dysfunctions in high-risk infants. However, the interpretation of these assessments lacks standardization and is subject to examiner bias.&#x0D; OBJECTIVES: Many infants with CP exhibit increased tonic stretch reflexes due to Upper Motor Neuron Syndrome (UMNS), resulting from motor neuron damage that disrupts muscle signalling.&#x0D; METHOD: To detect abnormal muscle reactions, our team employed an Inertial Measurement Unit (IMU) sensor, comprising three tri-axial sensors (accelerometer, gyroscope, magnetometer) that capture movement data continuously and unobtrusively. IMU sensors are compact, cost-effective, and have low processing requirements, requiring attachment to the infant's body to measure inter-body part angles. Our team analyzed muscle activity and posture using IMU sensors, collecting tri-axial data from 43 infants in real-time. Additional factors like age, stride length, and leg length were incorporated into the dataset.&#x0D; RESULTS: Our team has applied various supervised machine learning approaches to predict CP in infants due to the limited dataset size, validating models through k-fold cross-validation. Among the models, Naive Bayes (NB) outperformed Logistic Regression (LR), Decision Tree (DT), Linear Discriminant Analysis (LDA), k-Nearest Neighbors (kNN), and Support Vector Machine (SVM), achieving an accuracy of 88%. CONCLUSION: This research contributes to the early detection and intervention of CP in infants, potentially improving their long-term outcomes.

The use of muscle ultrasound to detect critical illness myopathy in patients with sepsis: an observational cohort study

BackgroundCritical illness myopathy (CIM) has negative impact on patient outcomes. We aimed to explore the diagnostic value of bedside ultrasonography for early identification of CIM in septic patients and its correlation with other diagnostic methods. This prospective observational study included 40 ICU patients diagnosed with sepsis on admission or within 48 h later according to the third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). They were evaluated using muscle ultrasound, electrodiagnostic and clinical muscle assessment (Medical Research Council, MRC) at two time points, the first was between days 2 and 5 and the second was between days 10 and 15.ResultsThere was significant deterioration of neuromuscular function between the two evaluation points demonstrated by decline in MRC, abnormal nerve conduction and electromyography (EMG) and increased muscle echogenicity on ultrasonography (P ≤ 0.001). Sepsis-Related Organ Failure Assessment (SOFA) score significantly correlated with different neuromuscular assessment tools. MRC had significant correlation with myopathic EMG (P ≤ 0.001, r = − 0.869) and increased muscle echogenicity (P ≤ 0.001, r = − 0.715). Abnormal ultrasonographic muscle architecture had sensitivity of 100%, specificity of 75% and positive likelihood ratio of 4 in detecting muscle dysfunction compared to myopathic EMG.ConclusionsBedside peripheral muscle ultrasound echogenicity grade could be used as an additional screening test in ICU septic patients for early detection of CIM.

Fabrication of biocompatible and biodegradable cloth-based sweat sensors using polylactic acid (PLA) via stencil transparent film-printing

Cloth-based sensors are gaining attention for creating microfluidic wearable sensors for continuous monitoring of sweat biomarkers because of their flexibility, low cost, and natural hydrophilicity making them suitable for integration into everyday products. Here, we present a novel, low-cost and simple fabrication approach to create a cloth-based sensor ready for use as a sweat sensor while being environmentally friendly using biocompatible and biodegradable material, polylactic acid (PLA), and a stencil transparent film-printing method. The method provided high-resolution structures with narrowest hydrophilic channels and hydrophobic barriers measuring 1.90 ± 0.34 mm and 1.23 ± 0.14 mm, respectively. Various designs for detecting sweat biomarkers, including pH, lactate, and chloride, were generated by simply adjusting the stencil transparent film designs. For pH detection, a square-shaped cloth-based sensor was constructed and different natural indicators was used as biocompatible and non-toxic reagents to measure pH providing the detection in the pH range of 1–14. In lactate determination, an enzymatic assay with nanoceria as colorimetric probes was used in a spot format, offering a lactate detection range of 2.5–25 mM, effectively distinguishing between normal and abnormal muscle fatigue patients at a cut-off level of 12.5 mM sweat lactate. For chloride, a distance-based format was employed using the reverse Mohr titration assay, resulting in a detection range of 10–100 mM. Finally, the analysis of lactate and chloride in artificial sweat was successfully demonstrated yielding the recovery in the acceptable range demonstrating accurate measurements of the fabricated cloth-based sensors.

Quantitative double echo steady state T2 mapping of upper extremity peripheral nerves and muscles.

T2 mapping can characterize peripheral neuropathy and muscle denervation due to axonal damage. Three-dimensional double echo steady-state (DESS) can simultaneously provide 3D qualitative information and T2 maps with equivalent spatial resolution. However, insufficient signal-to-noise ratio may bias DESS-T2 values. Deep learning reconstruction (DLR) techniques can reduce noise, and hence may improve quantitation of high-resolution DESS-T2. This study aims to (i) evaluate the effect of DLR methods on DESS-T2 values, and (ii) to evaluate the feasibility of using DESS-T2 maps to differentiate abnormal from normal nerves and muscles in the upper extremities, with abnormality as determined by electromyography. Analysis of images from 25 subjects found that DLR decreased DESS-T2 values in abnormal muscles (DLR = 37.71 ± 9.11 msec, standard reconstruction = 38.56 ± 9.44 msec, p = 0.005) and normal muscles (DLR: 27.18 ± 6.34 msec, standard reconstruction: 27.58 ± 6.34 msec, p < 0.001) consistent with a noise reduction bias. Mean DESS-T2, both with and without DLR, was higher in abnormal nerves (abnormal = 75.99 ± 38.21 msec, normal = 35.10 ± 9.78 msec, p < 0.001) and muscles (abnormal = 37.71 ± 9.11 msec, normal = 27.18 ± 6.34 msec, p < 0.001). A higher DESS-T2 in muscle was associated with electromyography motor unit recruitment (p < 0.001). These results suggest that quantitative DESS-T2 is improved by DLR and can differentiate the nerves and muscles involved in peripheral neuropathies from those uninvolved.

The occurrence of myopathies and meat abnormalities in modern broiler farming

Over the past few decades, there has been a significant increase in the production and consumption of poultry meat due to its high-quality nutritional profile, relatively low production costs, and ease of meat processing. This growing demand has led to progressive improvements in genetic selection for fast-growing broilers, triggering several spontaneous idiopathic muscle abnormalities along with an increased susceptibility to stress-induced myopathy. These muscle abnormalities have a negative impact on the quality of both fresh and processed chicken meat, primarily affecting the large breast muscle (m. pectoralis major) of broilers, which is also the most valuable part of the carcass. Frequent meat abnormalities include the occurrence of pale, soft, and exudative meat, primarily characterized by reduced water-holding capacity, while Deep Pectoral Myopathy results in a change in colour and a significant reduction in the attractive appearance of the small breast muscle (m. pectoralis minor). Myopathies labelled as "White Striping" are characterized by superficial white stripes, "Wooden Breast" is marked by pale and bulging areas of significant hardness, while "Spaghetti Meat" is described by the separation of muscle fibres resembling spaghetti pasta. These mentioned abnormalities and myopathies negatively impact the economic aspect of the poultry industry during the removal of affected parts and, furthermore, reduce the qualitative and nutritional value of the meat, posing challenges during technological processes. This paper describes recent findings on the occurrence, characteristics, and prevalence of the most common myopathies affecting modern broiler farming.

Detection of Rehabilitation Training Effect of Upper Limb Movement Disorder Based on MPL-CNN.

Stroke represents a medical emergency and can lead to the development of movement disorders such as abnormal muscle tone, limited range of motion, or abnormalities in coordination and balance. In order to help stroke patients recover as soon as possible, rehabilitation training methods employ various movement modes such as ordinary movements and joint reactions to induce active reactions in the limbs and gradually restore normal functions. Rehabilitation effect evaluation can help physicians understand the rehabilitation needs of different patients, determine effective treatment methods and strategies, and improve treatment efficiency. In order to achieve real-time and accuracy of action detection, this article uses Mediapipe's action detection algorithm and proposes a model based on MPL-CNN. Mediapipe can be used to identify key point features of the patient's upper limbs and simultaneously identify key point features of the hand. In order to detect the effect of rehabilitation training for upper limb movement disorders, LSTM and CNN are combined to form a new LSTM-CNN model, which is used to identify the action features of upper limb rehabilitation training extracted by Medipipe. The MPL-CNN model can effectively identify the accuracy of rehabilitation movements during upper limb rehabilitation training for stroke patients. In order to ensure the scientific validity and unified standards of rehabilitation training movements, this article employs the postures in the Fugl-Meyer Upper Limb Rehabilitation Training Functional Assessment Form (FMA) and establishes an FMA upper limb rehabilitation data set for experimental verification. Experimental results show that in each stage of the Fugl-Meyer upper limb rehabilitation training evaluation effect detection, the MPL-CNN-based method's recognition accuracy of upper limb rehabilitation training actions reached 95%. At the same time, the average accuracy rate of various upper limb rehabilitation training actions reaches 97.54%. This shows that the model is highly robust across different action categories and proves that the MPL-CNN model is an effective and feasible solution. This method based on MPL-CNN can provide a high-precision detection method for the evaluation of rehabilitation effects of upper limb movement disorders after stroke, helping clinicians in evaluating the patient's rehabilitation progress and adjusting the rehabilitation plan based on the evaluation results. This will help improve the personalization and precision of rehabilitation treatment and promote patient recovery.

FindD: AI-Driven Insights for Bone and Muscle Deficiencies Across Generations

This literature review examines a novel strategy for treating vitamin deficiencies, with a focus on vitamin D, vitamin K, and vitamin E. It also highlights the importance of deficiency of the vitamin D&amp;K for bone and the vitamin E for muscle abnormalities in children and adults. The research uses an extensive methodology that combines deep learning-based image processing techniques with machine learning for text-based question-and-answer(Q&amp;A) engagements. Through conversation, users are able to provide pertinent details about symptoms. Machine learning algorithms are then used to analyse the collected data. Concurrently, relevant images are processed by deep learning models to uncover subtle patterns that point to certain vitamin deficiencies. In order to address issues with bone caused by vitamin deficiencies, this research attempts to provide insights into the nexus of machine learning and deep learning for personalized diagnosis of vitamin deficiencies. The comprehensive method takes into account the multiplicity of variables affecting vitamin levels and how they affect bone health across age groups. This study's keywords are deep learning image processing, Q&amp;A-based machine learning, vitamin D, vitamin K, and vitamin E deficiencies, as well as bone abnormalities.

A rare pediatric neurometabolic disorder: Leigh syndrome

Subacute necrotizing encephalomyelopathy called Leigh Disease is a rare inherited pediatric neurological disorder generally involving infants. The condition primarily involves the central nervous system and the most involved structures are basal ganglia, thalamus, and brainstem. In this disorder, there is a progressive loss of mental and movement abilities associated with abnormal muscle tones, weakness, visual loss, respiratory failure, and strikingly, we got raised lactate levels in the blood, cerebral spinal fluid, and other body fluids. The prognosis of this condition is bad as there is no effective treatment and finally, the patient succumbs to death mostly due to respiratory failure. Here, we present a case of Leigh disease in an 8-month-old boy having chief complaints of delayed motor (weakness), and cognitive development with a previous history of recurrent respiratory infection. Upon recent radiological imaging, gross neurological abnormalities were seen which suggested the possibility of Leigh disease which was further confirmed by raised body fluid lactate levels.

Preventive education on adolescent idiopathic scoliosis in junior high school students at Surakarta

Adolescent idiopathic scoliosis (AIS) is a structural disorder of the vertebrae characterized by vertebral curvature exceeding 10°, commonly identified in children aged 10-18 years. Several contributing factors for AIS include genetic factors, abnormalities in connective tissue and skeletal muscles, biomechanical factors, and the use of school bags with associated weight. The primary issue identified from the preliminary study is the relatively high AIS rate, reaching 10.2%, with no previous preventive education programs implemented for students. The targeted participants for this program are students from Muhammadiyah Middle School 5 and Muhammadiyah Middle School 7 in Surakarta. The team conducted AIS prevention health education sessions in April-May 2023 for students aged 12-15 years. The educational activities involved the use of informative materials such as pocket books and videos, covering topics like the definition of Adolescent Idiopathic Scoliosis, physical examination methods for AIS, and preventive measures through posture correction exercises and the proper use of school bags.Results from the influence test, employing the Paired Sample T-Test, indicate a Sig. (2-tailed) value of 0.023. This implies a significant difference in the average knowledge level before and after receiving education on AIS prevention.

Paxillin participates in the sphingosylphosphorylcholine-induced abnormal contraction of vascular smooth muscle by regulating Rho-kinase activation

BackgroundThe Ca2+-independent contraction of vascular smooth muscle is a leading cause of cardiovascular and cerebrovascular spasms. In the previous study, we demonstrated the involvement of Src family protein tyrosine kinase Fyn and Rho-kinase in the sphingosylphosphorylcholine (SPC)-induced abnormal and Ca2+-independent contraction of vascular smooth muscle, but the specific mechanism has not been completely clarified.MethodsPaxillin knockdown human coronary artery smooth muscle cells (CASMCs) and smooth muscle-specific paxillin knockout mice were generated by using paxillin shRNA and the tamoxifen-inducible Cre-LoxP system, respectively. CASMCs contraction was observed by time-lapse recording. The vessel contractility was measured by using a myography assay. Fyn, Rho-kinase, and myosin light chain activation were assessed by immunoprecipitation and western blotting. The paxillin expression and actin stress fibers were visualized by histological analysis and immunofluorescent staining.ResultsThe SPC-induced abnormal contraction was inhibited in paxillin knockdown CASMCs and arteries of paxillin knockout mice, indicating that paxillin is involved in this abnormal contraction. Further study showed that paxillin knockdown inhibited the SPC-induced Rho-kinase activation without affecting Fyn activation. In addition, paxillin knockdown significantly inhibited the SPC-induced actin stress fiber formation and myosin light chain phosphorylation. These results suggest that paxillin, as an upstream molecule of Rho-kinase, is involved in the SPC-induced abnormal contraction of vascular smooth muscle.ConclusionsThe present study demonstrated that paxillin participates in the SPC-induced abnormal vascular smooth muscle contraction by regulating Rho-kinase activation.Ak4aWCsjd4r4atTQ7PUYn2Video

Myoelectric interface for neurorehabilitation conditioning to reduce abnormal leg co-activation after stroke: a pilot study

BackgroundThe ability to walk is an important factor in quality of life after stroke. Co-activation of hip adductors and knee extensors has been shown to correlate with gait impairment. We have shown previously that training with a myoelectric interface for neurorehabilitation (MINT) can reduce abnormal muscle co-activation in the arms of stroke survivors.MethodsHere, we extend MINT conditioning to stroke survivors with leg impairment. The aim of this pilot study was to assess the safety and feasibility of using MINT to reduce abnormal co-activation between hip adductors and knee extensors and assess any effects on gait. Nine stroke survivors with moderate to severe gait impairment received 6 h of MINT conditioning over six sessions, either in the laboratory or at home.ResultsMINT participants completed a mean of 159 repetitions per session without any adverse events. Further, participants learned to isolate their muscles effectively, resulting in a mean reduction of co-activation of 70% compared to baseline. Moreover, gait speed increased by a mean of 0.15 m/s, more than the minimum clinically important difference. Knee flexion angle increased substantially, and hip circumduction decreased.ConclusionMINT conditioning is safe, feasible at home, and enables reduction of co-activation in the leg. Further investigation of MINT’s potential to improve leg movement and function after stroke is warranted. Abnormal co-activation of hip adductors and knee extensors may contribute to impaired gait after stroke.Trial registration This study was registered at ClinicalTrials.gov (NCT03401762, Registered 15 January 2018, https://clinicaltrials.gov/study/NCT03401762?tab=history&a=4).

Magnetic resonance imaging of extraocular rectus muscles abnormalities in acute acquired concomitant esotropia.

To investigate the difference of medial rectus (MR) and lateral rectus (LR) between acute acquired concomitant esotropia (AACE) and the healthy controls (HCs) detected by magnetic resonance imaging (MRI). A case-control study. Eighteen subjects with AACE and eighteen HCs were enrolled. MRI scanning data were conducted in target-controlled central gaze with a 3-Tesla magnetic resonance scanner. Extraocular muscles (EOMs) were scanned in contiguous image planes 2-mm thick spanning the EOM origins to the globe equator. To form posterior partial volumes (PPVs), the LR and MR cross-sections in the image planes 8, 10, 12, and 14 mm posterior to the globe were summed and multiplied by the 2-mm slice thickness. The data were classified according to the right eye, left eye, dominant eye, and non-dominant eye, and the differences in mean cross-sectional area, maximum cross-sectional area, and PPVs of the MR and LR muscle in the AACE group and HCs group were compared under the above classifications respectively. There were no significant differences between the two groups of demographic characteristics. The mean cross-sectional area of the LR muscle was significantly greater in the AACE group than that in the HCs group in the non-dominant eyes (P=0.028). The maximum cross-sectional area of the LR muscle both in the dominant and non-dominant eye of the AACE group was significantly greater than the HCs group (P=0.009, P=0.016). For the dominant eye, the PPVs of the LR muscle were significantly greater in the AACE than that in the HCs group (P=0.013), but not in the MR muscle (P=0.698). The size and volume of muscles dominant eyes of AACE subjects change significantly to overcome binocular diplopia. The LR muscle become larger to compensate for the enhanced convergence in the AACE.

Muscle abnormalities worsen after post-exertional malaise in long COVID

A subgroup of patients infected with SARS-CoV-2 remain symptomatic over three months after infection. A distinctive symptom of patients with long COVID is post-exertional malaise, which is associated with a worsening of fatigue- and pain-related symptoms after acute mental or physical exercise, but its underlying pathophysiology is unclear. With this longitudinal case-control study (NCT05225688), we provide new insights into the pathophysiology of post-exertional malaise in patients with long COVID. We show that skeletal muscle structure is associated with a lower exercise capacity in patients, and local and systemic metabolic disturbances, severe exercise-induced myopathy and tissue infiltration of amyloid-containing deposits in skeletal muscles of patients with long COVID worsen after induction of post-exertional malaise. This study highlights novel pathways that help to understand the pathophysiology of post-exertional malaise in patients suffering from long COVID and other post-infectious diseases.

Inherited Arrhythmias in the Pediatric Population: An Updated Overview.

Pediatric cardiomyopathies (CMs) and electrical diseases constitute a heterogeneous spectrum of disorders distinguished by structural and electrical abnormalities in the heart muscle, attributed to a genetic variant. They rank among the main causes of morbidity and mortality in the pediatric population, with an annual incidence of 1.1-1.5 per 100,000 in children under the age of 18. The most common conditions are dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM). Despite great enthusiasm for research in this field, studies in this population are still limited, and the management and treatment often follow adult recommendations, which have significantly more data on treatment benefits. Although adult and pediatric cardiac diseases share similar morphological and clinical manifestations, their outcomes significantly differ. This review summarizes the latest evidence on genetics, clinical characteristics, management, and updated outcomes of primary pediatric CMs and electrical diseases, including DCM, HCM, arrhythmogenic right ventricular cardiomyopathy (ARVC), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), long QT syndrome (LQTS), and short QT syndrome (SQTS).