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Cureus May 2024The thyroid gland is an essential endocrine organ that secretes hormones to regulate homeostasis across multiple organ systems throughout the body. It is actively...
The thyroid gland is an essential endocrine organ that secretes hormones to regulate homeostasis across multiple organ systems throughout the body. It is actively regulated by the hypothalamic-pituitary-thyroid (HPT) axis, where negative feedback modulates the amounts of active hormone being released; thus, lesions that disrupt the proper functioning of this gland or its regulatory mechanisms can be destructive. Toxic thyroid adenomas are usually singular benign functioning nodules in the thyroid gland that cause thyrotoxicosis. Hyperthyroidism is commonly clinically silent, however, in most symptomatic cases, patients will be diagnosed based on abnormal laboratory findings and typical hyperthyroid symptoms. This case report examines an 81-year-old male with an extensive medical history who presented with complaints of new-onset generalized fatigue coupled with bilateral lower extremity muscle cramps. A positron emission tomography (PET) scan for other medical conditions incidentally noted mildly increased uptake in the thyroid gland, prompting a further investigation that resulted in a diagnosis of toxic thyroid adenoma. The patient responded well to treatment with methimazole and has remained in a euthyroid state.
PubMed: 38947590
DOI: 10.7759/cureus.61322 -
Biomedical Engineering Letters Jul 2024Surface electromyography (sEMG) is a non-invasive technique to characterize muscle electrical activity. The analysis of sEMG signals under muscle fatigue play a crucial...
PURPOSE
Surface electromyography (sEMG) is a non-invasive technique to characterize muscle electrical activity. The analysis of sEMG signals under muscle fatigue play a crucial part in the branch of neurorehabilitation, sports medicine, biomechanics, and monitoring neuromuscular pathologies. In this work, a method to transform sEMG signals to complex networks under muscle fatigue conditions using Markov transition field (MTF) is proposed. The importance of normalization to a constant Maximum voluntary contraction (MVC) is also considered.
METHODS
For this, dynamic signals are recorded using two different experimental protocols one under constant load and another referenced to 50% MVC from Biceps brachii of 50 and 45 healthy subjects respectively. MTF is generated and network graph is constructed from preprocesses signals. Features such as average self-transition probability, average clustering coefficient and modularity are extracted.
RESULTS
All the extracted features showed statistical significance for the recorded signals. It is found that during the transition from non-fatigue to fatigue, average clustering coefficient decreases while average self-transition probability and modularity increases.
CONCLUSION
The results indicate higher degree of signal complexity during non-fatigue condition. Thus, the MTF approach may be used to indicate the complexity of sEMG signals. Although both datasets showed same trend in results, sEMG signals under 50% MVC exhibited higher separability for the features. The inter individual variations of the MTF features is found to be more for the signals recorded using constant load. The proposed study can be adopted to study the complex nature of muscles under various neuromuscular conditions.
PubMed: 38946822
DOI: 10.1007/s13534-024-00372-5 -
Free Radical Biology & Medicine Jun 2024Due to an unexpected activation of different zinc (Zn) transporters in a recent prospective clinical study, we have revisited the role of Zn homeostasis and the...
Reactive oxygen species in skeletal muscle injury, fatigue, regeneration and ageing: In memory of John Faulkner The role of zinc and matrix metalloproteinases in myofibrillar protein degradation in critical illness myopathy.
Due to an unexpected activation of different zinc (Zn) transporters in a recent prospective clinical study, we have revisited the role of Zn homeostasis and the activation of matrix metalloproteinases (MMPs) in skeletal muscle exposed to the intensive care unit (ICU) condition (immobilization and mechanical ventilation). ICU patients exposed to 12 days ICU condition were followed longitudinally with six repeated muscle biopsies while they showed a progressive preferential myosin loss, i.e., the hallmark of Critical Illness Myopathy (CIM), in parallel with the activation of Zn-transporters. In this study, we have revisited the expression of Zn-transporters and the activation of MMPs in clinical as well as in experimental studies using an established ICU model. MMPs are a group Zn-dependent endopeptidases which do not only target and cleave extracellular proteins but also intracellular proteins including multiple sarcomeric proteins. MMP-9 is of specific interest since the hallmark of CIM, the preferential myosin loss, has also been reported in dilated cardiomyopathy and coupled to MMP-9 activation. Transcriptional activation of Zn-transporters was observed in both clinical and experimental studies as well as the activation of MMPs, in particular MMP-9, in various limb and respiratory muscles in response to long-term exposure to the ICU condition. The activation of Zn-transporters was paralleled by increased Zn levels in skeletal muscle which in turn showed a negative linear correlation with the preferential myosin loss associated with CIM, offering a potential intervention strategy. Thus, activation of Zn-transporters, increased intramuscular Zn levels, and activation of the Zn-dependent MMPs are forwarded as a probable mechanism involved in CIM pathophysiology. These effects were confirmed in different rat strains subjected to a model of CIM and exacerbated by old age. This is of specific interest since old age and muscle wasting are the two factors most strongly associated with ICU mortality.
PubMed: 38944212
DOI: 10.1016/j.freeradbiomed.2024.06.022 -
Heart & Lung : the Journal of Critical... Jun 2024Aeorobic exercise is an essential component of the pulmonary rehabilitation program for patients with chronic obstructive pulmonary disease (COPD). Single-limb exercises... (Review)
Review
BACKGROUND
Aeorobic exercise is an essential component of the pulmonary rehabilitation program for patients with chronic obstructive pulmonary disease (COPD). Single-limb exercises are a type of aeorobic exercise that aims to increase patient tolerance by reducing the workload of the respiratory system.
OBJEKTIVES
The aim of our systematic review was to determine the effects of single-limb exercises on pulmonary function, dyspnea, fatigue, and muscle dysfunction in patients with COPD.
METHODS
Searches were performed using PubMed, Pedro, Google Scholar, MEDLINE, EMBASE, Scopus, Cochrane Library, Web of Science databases. Publications from the beginning to 2023 searched. Studies were selected by two authors by scanning the title, Mesh terms abstract in Rayyan QCRI software. Selected studies were subjected to full-text screening by applying selection criteria. Randomized controlled, case-control, cohort studies were included.
RESULTS
In the first screening according to mesh terms, 1011 articles were identified. After the screening criteria and duplicate articles were evaluated, 10 articles were included. This systematic review includes seven case-control, one randomized control trial (RCT), one cross-sectional, and one non-randomized study. A total of 157 patients with COPD received treatment in these studies. According to the Bakker scale, single-limb exercises have been shown to improve pulmonary function with strong evidence. There is strong evidence that single-limb exercises have no effect on dyspnea and fatigue in COPD patients. There is limited evidence that single-limb exercises have an effect on functional exercise capacity.
CONCLUSION
Single-limb exercise can advised in terms of improving pulmonary function in patients with COPD. Current systematic review has found single limb exercise has no effect on dyspnea and fatigue perception. No side effects were reported in the studies and these exercises can be considered safe.
PubMed: 38941773
DOI: 10.1016/j.hrtlng.2024.06.004 -
Sarcoidosis, Vasculitis, and Diffuse... Jun 2024Adequate respiratory muscle strength is required to meet the increased ventilatory demand during physical activities. However, it is not well known whether respiratory...
BACKGROUND
Adequate respiratory muscle strength is required to meet the increased ventilatory demand during physical activities. However, it is not well known whether respiratory muscle strength is impaired in patients with idiopathic pulmonary fibrosis (IPF).
OBJECTIVES
This study aimed to investigate the relationship between respiratory muscle strength and exercise capacity, quality of life, physical activity level, and fatigue in IPF patients.
METHODS
The study comprised 30 individuals with idiopathic pulmonary fibrosis (IPF) and 30 healthy controls. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured to assess respiratory muscle strength. The International Physical Activity Questionnaire-Short Form, 6-minute walk test distance (6MWD), St George Respiratory Questionnaire (SGRQ), and Fatigue Severity Scale (FSS) were employed to evaluate physical activity level, exercise capacity, quality of life, and fatigue severity, respectively.
RESULTS
MIP (81±29 vs.73±20 cmH2O) and MEP (93±31 vs. 93±34 cmH2O) did not differ significantly between IPF patients and controls (p>0.05). In patients with IPF, MIP was significantly correlated with 6MWD (r=0.533), SGRQ (r=-0.428), and FSS (r=-0.433). Multivariate models including MIP, MEP, FEV1, FVC, and PA level explained 74% of the variance in the 6MWD (p<0.001), and MIP, FEV1, and PA level were independent predictors of the 6MWD, with FEV1 being the strongest predictor (β=0.659). Multivariate models predicting SGRQ revealed none of MIP, FEV1 or PA level was directly influencing the SGRQ score.
CONCLUSIONS
This study suggests that patients with IPF do not have respiratory muscle weakness. Inspiratory muscle strength has a direct influence on exercise capacity but an indirect effect on quality of life, probably by influencing exercise capacity.
PubMed: 38940715
DOI: 10.36141/svdld.v41i2.14884 -
Frontiers in Bioscience (Scholar... Jun 2024Several inherited metabolic fatty acid disorders present with myopathies. Skeletal muscle accounts for 40% of the body and is important for metabolism, exercise, and... (Review)
Review
Several inherited metabolic fatty acid disorders present with myopathies. Skeletal muscle accounts for 40% of the body and is important for metabolism, exercise, and movement. Muscle energy failure is manifested by metabolic crises with muscle weakness, sometimes associated with muscle fatigue and failure resulting in acute necrosis or rhabdomyolysis/myoglobinuria episodes. Lack of energy leads to muscle necrosis. Other presentations are weakness and myalgias with lipid storage myopathies in the biopsy. The biomarkers of such disorders are acyl-carnitine with various profiles and need to be carefully evaluated to plan supplementary therapy and specific diets. If red flags are not distinctly followed and diagnosed in time they might lead to a metabolic or cardiac failure.
Topics: Humans; Muscular Diseases; Carnitine; Lipid Metabolism, Inborn Errors; Muscle, Skeletal; Muscular Dystrophies
PubMed: 38939976
DOI: 10.31083/j.fbs1602012 -
Cureus Jun 2024Autoimmune hepatitis (AIH) is a condition resulting in chronic, inflammatory changes to the liver. Primary biliary cholangitis (PBC) is an autoimmune condition that...
Autoimmune hepatitis (AIH) is a condition resulting in chronic, inflammatory changes to the liver. Primary biliary cholangitis (PBC) is an autoimmune condition that destroys intrahepatic bile ducts. Overlap syndrome with concomitant AIH and PBC comprises a rare subgroup of patients with immune-mediated liver disease, with incidence rates of male patients being exceedingly uncommon in a predominantly female patient population. Our case report investigates a rare case of a 41-year-old male patient diagnosed with overlapping AIH and PBC. He initially presented with symptoms of fatigue, pruritus, and episodes of Raynaud's phenomenon, in addition to findings of persistently elevated liver enzymes despite lifestyle modifications. He had no past medical history, no history of alcohol use disorder, and no family medical history of chronic liver disease. Imaging did not reveal evidence of cirrhosis. Further diagnostic workup was significant for elevated immunologic markers for antinuclear antibodies (ANA) with positive centromere and cytoplasmic patterns, antimitochondrial antibodies (AMA) with F-actin antibodies, anti-smooth muscle antibodies (ASMA), and cytoplasmic antinuclear cytoplasmic antibodies (ANCA C). Liver biopsy showed prominent plasma cells and rare granulomas, consistent with the diagnosis of AIH with a component of PBC, respectively. He was started on ursodeoxycholic acid (UDCA), demonstrating a near-complete clinical response with resolution of symptoms and normalization of liver enzymes. Studies investigating the low incidence of male patients with overlap syndrome are limited, as current research is overwhelmingly based on studies with predominantly female subjects. However, most studies generally recommend treatment with both UDCA and corticosteroids to reduce symptoms and biochemical markers. Our case report highlights a rare case of a male patient documenting excellent biochemical and clinical responses to monotherapy with UDCA. A possible theory is that our patient's early treatment (prior to advanced disease progression) is associated with his near-complete biochemical response and symptomatic resolution on UDCA alone. Further research is needed to fully understand the clinical course and long-term prognosis of male patients with overlap syndrome. Our patient remains in life-long follow-up to monitor if or when he requires treatment with corticosteroids in addition to current monotherapy with UDCA..
PubMed: 38938909
DOI: 10.7759/cureus.63312 -
Scientific Reports Jun 2024We developed a composite symptom score (CSS) representing disease-related symptom burden over time in patients with malignant pleural mesothelioma (MPM). Longitudinal...
We developed a composite symptom score (CSS) representing disease-related symptom burden over time in patients with malignant pleural mesothelioma (MPM). Longitudinal data were collected from an open-label Phase IIB study in which 239 patients completed the validated MD Anderson Symptom Inventory for MPM (MDASI-MPM). A blinded, independent review committee of external patient-reported outcomes experts advised on MDASI-MPM symptoms to include in the CSS. Through iterative analyses of potential symptom-item combinations, 5 MPM symptoms (pain, fatigue, shortness of breath, muscle weakness, coughing) were selected. The CSS correlated strongly with the full MDASI-MPM symptom set (0.92-0.94) and the Lung Cancer Symptom Scale-Mesothelioma (0.79-0.87) at each co-administration of the scales. The CSS also had good sensitivity to worsening disease and global quality-of-life ratings. The MDASI-MPM CSS can be used as an outcome in MPM clinical trials, including in responder analyses and at the individual patient level. It is brief enough to administer frequently, including electronically, to better capture symptom trajectories during and after a trial and in clinical practice. As a single score, the CSS addresses multiplicity issues that can arise when several symptoms increase due to worsening disease. Our process can be adapted to produce a CSS for other advanced-cancer trials.
Topics: Humans; Mesothelioma, Malignant; Male; Female; Pleural Neoplasms; Aged; Middle Aged; Quality of Life; Lung Neoplasms; Mesothelioma; Patient Reported Outcome Measures; Fatigue; Symptom Assessment; Longitudinal Studies; Severity of Illness Index; Symptom Burden
PubMed: 38937473
DOI: 10.1038/s41598-024-62307-5 -
Brazilian Journal of Physical Therapy Jun 2024Runners seek health benefits and performance improvement. However, fatigue might be considered a limiting factor. Transcranial Direct Current Stimulation (tDCS) has been...
Does Transcranial Direct Current Stimulation reduce central and peripheral muscle fatigue in recreational runners? A triple-blind, sham-controlled, randomized, crossover clinical study.
BACKGROUND
Runners seek health benefits and performance improvement. However, fatigue might be considered a limiting factor. Transcranial Direct Current Stimulation (tDCS) has been investigated to improve performance and reduce fatigue in athletes. While some studies showing that tDCS may improve a variety of physical measures, other studies failed to show any benefit.
OBJECTIVE
To evaluate the acute effects of tDCS on central and peripheral fatigue compared to a sham intervention in recreational runners.
METHODS
This is a triple-blind, controlled, crossover study of 30 recreational runners who were randomized to receive one of the two interventions, anodal or sham tDCS, after the fatigue protocol. The interventions were applied to the quadriceps muscle hotspot for 20 min. Peak torque, motor-evoked potential, and perceived exertion rate were assessed before and after the interventions, and blood lactate level was assessed before, during, and after the interventions. A generalized estimated equation was used to analyze the peak torque, motor-evoked potential, and blood lactate data, and the Wilcoxon test was used for perceived exertion rate data.
RESULTS
Our findings showed no difference between anodal tDCS and sham tDCS on peak torque, motor-evoked potential, blood lactate, and perceived exertion rate.
CONCLUSION
The tDCS protocol was not effective in improving performance and reducing fatigue compared to a sham control intervention.
BRAZILIAN CLINICAL TRIALS REGISTRY
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PubMed: 38936315
DOI: 10.1016/j.bjpt.2024.101088 -
Medicine and Science in Sports and... Jun 2024This study investigated the magnitude and etiology of neuromuscular fatigue and muscle damage induced by eccentric cycling compared to conventional concentric cycling in...
INTRODUCTION
This study investigated the magnitude and etiology of neuromuscular fatigue and muscle damage induced by eccentric cycling compared to conventional concentric cycling in patients with breast cancer.
METHODS
After a gradual familiarization protocol for eccentric cycling, nine patients with early-stage breast cancer performed three cycling sessions in eccentric or concentric mode. The eccentric cycling session (ECC) was compared to concentric cycling sessions matched for power output (CONpower, 80% of concentric peak power output, 95 ± 23 W) or oxygen uptake (10 ± 2 mL.min.kg-1). Pre- to postexercise changes (30s through 10 min recovery) in knee extensor maximal voluntary contraction force (MVC), voluntary activation, and quadriceps potentiated twitch force (Qtw) were quantified to determine global, central, and peripheral fatigue, respectively. Creatine kinase (CK) and lactate dehydrogenase (LDH) activities were measured in the plasma before and 24 h postexercise as markers of muscle damage.
RESULTS
Compared to CONpower (-11 ± 9%) and (-5 ± 5%), the ECC session resulted in a greater decrease in MVC (-25 ± 12%) postexercise (P < 0.001). Voluntary activation decreased only in ECC (-9 ± 6% postexercise, P < 0.001). The decrease in Qtw was similar postexercise between ECC and CONpower (-39 ± 21% and -40 ± 16%, P > 0.99) but lower in (P < 0.001). The CONpower session resulted in twofold greater compared to the ECC and sessions (P < 0.001). No change in CK or LDH activity was reported from preexercise to 24 h postexercise.
CONCLUSIONS
The ECC session induced greater neuromuscular fatigue compared to the concentric cycling sessions without generating severe muscle damage. ECC is a promising exercise modality for counteracting neuromuscular maladaptation in patients with breast cancer.
PubMed: 38935539
DOI: 10.1249/MSS.0000000000003506