Search Results (1,429)

Optimizing the neuromechanical determinants of explosive performance remains a key objective in sports science. This study compared the effects of an eight-week movement-pattern-based training program (MPT) with an isometric strength training protocol (ITG) on countermovement jump (CMJ) mechanics in competitive track and field athletes. Thirty-four athletes (19 men, 15 women) with ≥7 years of training experience were randomly allocated to the MPT or ITG. Pre- and post-intervention assessments were conducted using dual force plates to evaluate jump height, musculotendinous stiffness, concentric and eccentric impulses, contraction time, eccentric-to-concentric force ratio, and rate of force development (RFD). The MPT elicited significant gains in stiffness (Δ = +840.94 ± 1302.21 N/m; p = 0.002), maintained concentric peak force, and reduced contraction time (Δ = –64.53 ± 190.32 ms; p = 0.01), suggesting improved elastic efficiency and neuromuscular timing. Conversely, ITG was associated with reductions in concentric peak force (Δ = –66.18 ± 77.45 N; p = 0.003) and stiffness (Δ = –691.94 ± 1414.41 N/m) and an increase in the eccentric-to-concentric force ratio (Δ = +1.99%; p = 0.006). The RFD changes were inconsistent across both groups. These findings indicate that dynamic multi-joint training confers superior neuromechanical adaptations compared to isolated isometric loading. From a performance perspective, programming strategies should prioritize movement-specific dynamic tasks to enhance the explosive qualities critical for sprinting, jumping, and multidirectional field sports. Full article

Background: Muscle latency is an often-overlooked factor contributing to increased implant wear and higher rates of hip and knee osteoarthritis. Latency reduces the protective role of muscles against external joint loads during movement initiation, leading to cumulative microtrauma. This study investigates whether preliminary quadriceps contraction can mitigate these adverse effects during early rehabilitation after arthroplasty. Materials and methods: The study was conducted in two university hospitals in Sofia, Bulgaria, including 46 patients (mean age 63.76 ± 9.49 years): 25 with hip arthroplasty and 21 with knee arthroplasty. Participants were randomly assigned to a control group (n = 25; 13 hip, 12 knee: standard postoperative advice) or an experimental group (n = 21; 12 hip, 9 knee: standard advice plus preliminary quadriceps contraction). Primary outcome: pain intensity (VAS). Secondary outcomes: range of motion (ROM, %), manual muscle testing (MMT, %), thigh circumference difference (cm), and success rate of preliminary quadriceps contraction (%). Results: Both groups improved after one month (p < 0.05), but the experimental group showed significantly greater improvement (p < 0.05). Higher success rates of preliminary quadriceps contraction correlated with greater improvements in all outcomes (p < 0.05). Conclusions: Preliminary quadriceps contraction enhances standard postoperative advice by reducing pain, improving mobility and muscle strength, and reducing hypotrophy during early rehabilitation after hip and knee arthroplasty. Patients should be encouraged to perform it consistently, even when pain subsides. Full article

Atrial fibrillation (AF) is a prevalent heart arrhythmia, characterized by an irregularly irregular rhythm and the absence of identifiable P waves on ECG. Given the loss of effective atrial contraction, AF carries a risk of serious complications. If untreated, AF can promote thrombogenesis, leading to stroke, systemic embolism (e.g., limb or organ ischemia), and myocardial infarction. These serious complications highlight the importance of understanding AF and assessing stroke risk to guide optimal management of this chronic arrhythmia. Congruent with recent technological developments, advanced imaging has emerged as a modality to better understand AF. This review highlights advanced imaging techniques and their advantages, with a focus on 4D flow MRI, a novel modality that enables visualization of blood flow patterns in three dimensions and provides unique insights into cardiac hemodynamics. It also synthesizes the current literature on key hemodynamic markers identified by 4D flow MRI, including blood flow stasis, wall shear stress, and vorticity. Quantifying these markers has improved predictive accuracy of future stroke risk in AF patients, allowing clinicians to risk stratifying their patients and optimize management. Finally, the review discusses potential future markers that may further refine our understanding of AF and inform patient care. Full article

Background/Objectives: Encouraged by the traditional use of Cotinus coggygria Scop. (European smoketree) for its anti-inflammatory and antioxidant properties, and considering the limitations of current therapies for recurrent aphthous stomatitis (RAS), we aimed to develop and evaluate a mucoadhesive oral gel containing C. coggygria stem bark extract. Methods: A thermosensitive gel was formulated using Carbopol^® 974P NF and poloxamer 407, enriched with 5% C. coggygria extract (CC gel), and characterized for its organoleptic properties, pH, electrical conductivity, and storage stability over six months. Therapeutic efficacy was assessed in a Wistar albino rat model of chemically induced oral ulcers. Animals were divided into three groups: untreated controls (CTRL), rats treated with gel base (GB), and those treated with CC gel over a 10-day period. Healing progression was monitored macroscopically (ulcer size reduction), biochemically (oxidative stress markers in plasma and tissue), and histologically. Results: The CC gel demonstrated satisfactory physicochemical stability and mucosal compatibility. Moreover, it significantly accelerated ulcer contraction and achieved complete re-epithelialization by day 6. Biochemical analyses revealed reduced TBARS and increased SOD, CAT, and GSH levels in ulcer tissue, indicating enhanced local antioxidant defense. Histological evaluation confirmed early resolution of inflammation, pronounced fibroblast activity, capillary proliferation, and full epithelial regeneration in the CC group, in contrast to delayed healing and persistent inflammatory infiltration in the GB and CTRL groups. Conclusions: These findings indicate that the CC gel has potential as a natural, topical formulation with antioxidant and regenerative properties for RAS, although further studies, including clinical evaluation, are required to confirm its overall efficacy and long-term safety. Full article

Background/Objectives: Adults aged 19–59 with diabetes are recommended by the Advisory Committee on Immunization Practices (ACIP) to receive vaccination against Hepatitis B Virus (HBV) infection because of their increased risk of contracting HBV. This study aimed to examine hepatitis B (HepB) vaccination rates among U.S. adults aged 19–59 years with diabetes and explore sociodemographic factors associated with HepB vaccination. Methods: Data from the 2015–2018 National Health and Nutrition Examination Survey (NHANES) were analyzed to compare HepB vaccination between adults with and without diabetes. Weighted Chi-square analysis was used to test the associations between HepB vaccination status and various categorical variables. Weighted logistic regression was employed to identify factors associated with being fully vaccinated. Results: A total of 5988 adults aged 19–59 were included in the study, of whom 504 (8.4%) had diabetes. The HepB vaccination rate was 32.3% for those with diabetes vs. 43.6% for those without diabetes (p = 0.01). However, after adjusting for other covariates, having diabetes was not associated with being fully vaccinated against HBV (p = 0.583). Adults aged 45–59 years were less likely to be vaccinated against HBV compared to those aged 19–29 (OR: 0.12, p < 0.0001). Having health insurance, being female, and having a higher educational level were all associated with HepB vaccination status (all p < 0.01). Overall, the HBV infection rate was 1.1%. Having HepB vaccination was associated with a lower risk of HBV infection among both groups with and without diabetes. Conclusions: HepB vaccination among U.S. adults with diabetes was suboptimal and lower than among those without diabetes. Age and education were associated with being fully vaccinated against HBV. Future research is needed to identify and better understand barriers to receiving HepB vaccines. Full article

Background: Chronic neck pain (CNP) is considered a widespread musculoskeletal condition which affects the quality of life and is associated with scapular stabilizer dysfunction patterns. This study aimed to compare the morphological, functional, and strength-related characteristics of the lower trapezius muscle (such as muscle thickness at rest and during contraction, contraction-to-relaxation ratios, contraction and relaxation velocities, and force production) between individuals with CNP and asymptomatic controls. Methods: This cross-sectional study comprises 144 participants (78 with CNP and 76 controls) aged 18–30 years. Ultrasound imaging was used to assess muscle thickness, contraction and relaxation velocities, and contraction ratios. Muscle strength, including peak force and rate of force development, was evaluated using dynamometry. Participants with CNP were categorized by neck disability index (NDI) scores into mild, moderate, and severe groups. Results: Participants with CNP showed reduced contraction velocity (0.60 ± 0.24 cm/s vs. 0.81 ± 0.44 cm/s; p < 0.001; d = 0.61), lower relaxation velocity (0.48 ± 0.28 cm/s vs. 0.58 ± 0.32 cm/s; p = 0.038; d = 0.34), and decreased peak force (4.83 ± 3.27 kg vs. 6.00 ± 3.87 kg; p = 0.043; d = 0.33) compared to controls. Muscle thickness and contraction ratio differences were non-significant. Among CNP subgroups, the contraction ratio was lower in the severe disability group compared to the mild group (0.25 ± 0.19 vs. 0.53 ± 0.33; p = 0.015). Conclusions: The present study showed functional impairments of the lower trapezius muscle in individuals with CNP, particularly reduced contraction and relaxation velocities and lower peak force, with more pronounced deficits in those with severe disability. While no significant differences in muscle thickness were found, these findings suggest that functional alterations may precede structural changes. Full article

Background: Calcium is essential for maintaining bone health, facilitating muscle contractions, regulating body temperature, and supporting aerobic metabolism. While the relationship between physical activity and calcium metabolism is well established, the impact of calcium intake on cardiorespiratory fitness (CRF) remains underexplored. The main aim of this study was to assess the effects of calcium intake on CRF and the mediation effect of calcium intake on the relationship between vigorous physical activity participation and CRF. Methods: Analyses were performed on a sample of 576 adult participants (257 males and 319 females) from the Quebec Family Study (QFS) for whom data were available for calcium intake, CRF, and body composition. The effects of calcium intake on CRF and body composition were analyzed by comparing subjects classified into sex-specific tertiles of calcium intake using general linear mixed models. Pearson correlations were also used to document the associations between calcium intake, CRF, and body composition. A mediation analysis was used to determine the effect of calcium intake as a mediator of the association between vigorous physical activity and CRF. Results: The comparison of calcium-based tertiles revealed that low calcium consumers had lower CRF, especially in males. In both males and females, correlation analysis showed that calcium intake was positively associated (p < 0.05) with CRF. Mediation analyses revealed that calcium intake explains an insignificant fraction of the physical activity–CRF relationship. Between-tertile comparisons showed reduced body fat and increased fat-free mass levels when increasing calcium intake, although some of these effects were not statistically significant. Conclusions: The results of this study suggest that low calcium intake is associated with reduced aerobic capacity in adult males and females. While the positive relationship observed between calcium and aerobic fitness aligns with calcium’s known physiological roles, further research is needed to clarify the exact mechanisms by which this micronutrient may influence aerobic capacity. Full article

Glottic insufficiency, often caused by laryngeal nerve injury, impairs voice quality and breathing. Current treatments, such as hyaluronic acid injection, require frequent reapplication every 3–6 months. This study aimed to investigate the therapeutic potential of small extracellular vesicles (sEVs) derived from Wharton’s Jelly mesenchymal stem cells (WJMSCs) incorporated into genipin-crosslinked gelatin hydrogels (GCGHs) for promoting vocal fold fibroblast (VFFs) regeneration in vitro. WJMSCs were isolated from umbilical cords, expanded to passage 4, and used for sEV isolation via tangential flow filtration (TFF). The sEVs (585.89 ± 298.93 µg/mL) were characterized using bicinchoninic acid assay (BCA), nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and Western blot. Seven concentrations of sEVs were tested on VFFs to evaluate cytotoxicity and proliferation, identifying 75 µg/mL as the optimal dose. GCGHs were then combined with WJMSCs and sEVs and evaluated for physicochemical properties, degradation, biocompatibility, and immune response. The hydrogels were injectable within 20 min and degraded in approximately 42 ± 0.72 days. The optimal sEV concentration significantly enhanced VFFs proliferation (166.59% ± 28.11) and cell viability (86.16% ± 8.55, p < 0.05). GCGH-MSCs showed the highest VFFs viability (82.04% ± 10.51) and matrix contraction (85.98% ± 1.25) compared to other groups. All hydrogel variants demonstrated minimal immune response when co-cultured with peripheral blood mononuclear cells (PBMCs). GCGH is a promising scaffold for delivering WJMSCs and sEVs to support VFF regeneration, with demonstrated biocompatibility and regenerative potential. Further in vivo studies are warranted to validate these findings. Full article

The potential hazards of triazole fungicides to non-target organisms necessitate environmental risk assessment. This study, therefore, focused on characterizing the differential toxicity of the enantiomers of Ipfentrifluconazole (IFZ), a new triazole fungicide, in zebrafish larvae using a multi-endpoint approach. Acute toxicity tests determined the LC₅₀ values of 1.709 mg/L for rac-IFZ, 1.531 mg/L for (+)-IFZ, and 1.809 mg/L for (−)-IFZ, indicating a higher toxicity of the (+)-enantiomer. To avoid overt mortality while revealing organ-level effects, we chose a concentration of approximately 20% of the LC50 of (+)-IFZ, which is 340 μg/L, as the exposure concentration. Exposure to IFZ induced developmental defects, including swim bladder malformation, cardiac blood pooling, and metabolic disturbances during the early developmental stage of zebrafish. Additionally, cardiac and hepatic development and function were disrupted in zebrafish larvae following IFZ exposure. Biochemical and transcriptomic analyses revealed distinct toxic mechanisms: (+)-IFZ primarily disrupted lipid metabolism through alterations in PPAR signaling pathway and fatty acid degradation, while (−)-IFZ significantly impaired cardiac function by affecting adrenergic signaling in cardiomyocytes and cardiac muscle contraction. Rac-IFZ mainly influenced drug metabolism, particularly cytochrome P450-related pathways. These findings demonstrated the toxic effects of IFZ, emphasizing the need for evaluating environmental and health risks of chiral pesticides. The study provides valuable insights into the molecular mechanisms underlying IFZ toxicity. Full article

Skeletal muscle, constituting 40–50% of total body mass, is vital for mobility, posture, and systemic homeostasis. Muscle contraction heavily relies on ATP, primarily generated by mitochondrial oxidative phosphorylation. Mitochondria play a key role in decoding intracellular calcium signals. The endocannabinoid system (ECS), including CB₁ receptors (CB₁Rs), broadly influences physiological processes and, in muscles, regulates functions like energy metabolism, development, and repair. While plasma membrane CB₁Rs (pCB₁Rs) are well-established, a distinct mitochondrial CB₁R (mtCB₁R) population also exists in muscles, influencing mitochondrial oxidative activity and quality control. We investigated the role of mtCB₁Rs in skeletal muscle physiology using a novel systemic mitochondrial CB₁ deletion murine model. Our in vivo studies showed no changes in motor function, coordination, or grip strength in mtCB₁ knockout mice. However, in vitro force measurements revealed significantly reduced specific force in both fast-twitch (EDL) and slow-twitch (SOL) muscles following mtCB₁R ablation. Interestingly, knockout EDL muscles exhibited hypertrophy, suggesting a compensatory response to reduced force quality. Electron microscopy revealed significant mitochondrial morphological abnormalities, including enlargement and irregular shapes, correlating with these functional deficits. High-resolution respirometry further demonstrated impaired mitochondrial respiration, with reduced oxidative phosphorylation and electron transport system capacities in knockout mitochondria. Crucially, mitochondrial membrane potential dissipated faster in mtCB₁ knockout muscle fibers, whilst mitochondrial calcium levels were higher at rest. These findings collectively establish that mtCB₁Rs are critical for maintaining mitochondrial health and function, directly impacting muscle energy production and contractile performance. Our results provide new insights into ECS-mediated regulation of skeletal muscle function and open therapeutic opportunities for muscle disorders and aging. Full article

Unaccustomed eccentric exercise is well established to induce exercise-induced muscle damage (EIMD), characterized by transient strength loss, delayed onset muscle soreness (DOMS), reduced range of motion, and proprioceptive disturbances. While limb dominance has been proposed as a potential modulator of susceptibility to EIMD, evidence remains inconclusive. This exploratory study aimed to compare alterations in muscle damage indices between dominant and non-dominant knee extensors 48 h after eccentric isokinetic exercise. Eighteen physically active young women (23 ± 2 years) completed two eccentric exercise sessions (5 × 15 maximal contractions at 60°/s), one per limb, with sessions separated by 24–30 days. For all participants, testing was conducted during the early follicular phase. Muscle strength (isometric and eccentric peak torque), DOMS (palpation and pain pressure threshold), range of motion, fatigue index, and position sense were assessed pre- and 48 h post-exercise. Significant reductions in isometric and eccentric peak torque, increased DOMS, impaired position sense, and altered fatigue index were observed 48 h post-exercise in the exercised limb (p < 0.001), with no differences between dominant and non-dominant limbs across all indices. These findings demonstrate that limb dominance does not influence the magnitude of EIMD in knee extensors of young women. Practical implications include equal consideration of both limbs in eccentric training, rehabilitation, and injury prevention programs. Full article

Background: The relationship between Helicobacter pylori (H. pylori) infection and gastroesophageal reflux disease (GERD) remains a topic of ongoing debate. In particular, the intragastric distribution of H. pylori—whether localized in the antrum or corpus—may influence gastric acid secretion and esophageal physiology in different ways. However, its potential effects on esophageal motility and reflux parameters have not been comprehensively evaluated using combined diagnostic tools. This study aimed to assess whether H. pylori positivity, based on its histologically confirmed intragastric localization, is associated with alterations in endoscopic, manometric, and reflux monitoring findings in patients with typical GERD symptoms. Methods: This retrospective study included 213 patients with typical reflux symptoms who underwent upper gastrointestinal endoscopy with gastric biopsies, high-resolution esophageal manometry (HREM), and 24 h multichannel intraluminal impedance–pH (MII-pH) monitoring. Based on histopathology, patients were classified into three groups: H. pylori-negative, antrum-predominant infection, and corpus-predominant infection. Clinical symptoms, endoscopic findings, reflux characteristics, and esophageal motility parameters were compared. Results: Of 213 patients, 90 were H. pylori-positive (60 antrum-predominant, 30 corpus-predominant). There were no significant differences between groups in terms of typical GERD symptoms, endoscopic esophagitis, DeMeester scores, acid exposure time, or mean nocturnal baseline impedance (MNBI). Nausea and chronic laryngitis were significantly more frequent in antral H. pylori-positive patients. Notably, contraction front velocity (CFV) was significantly lower in patients with antral H. pylori compared with H. pylori-negative individuals (p = 0.002), indicating subtle slowing of esophageal peristalsis. Although this reduction in CFV did not correlate with symptom severity or bolus clearance, it may represent early functional impairment of esophageal motility. Conclusions: Although H. pylori infection—particularly when antrum-predominant—is not associated with increased reflux burden or esophagitis, it may contribute to extra-esophageal symptoms and minor motility alterations such as reduced CFV. These findings suggest that routine H. pylori eradication in GERD patients may not be necessary solely based on reflux parameters. However, treatment decisions should be individualized based on symptom profiles and endoscopic findings, including the presence of peptic ulcers, premalignant gastric lesions, or a family history of gastric malignancy, in accordance with general H. pylori eradication criteria. Full article

Background: This study aims to investigate and monitor cardiorespiratory fitness levels, measured by the 6-minute walk test (6MWT) and quality of life (QoL), assessed using the Short form-36 (SF-36), in patients with hypertension, both with and without coronavirus disease 2019 (COVID-19), at a 3-month follow-up. Methods: Sixty participants were recruited, comprising two groups: hypertensive patients with COVID-19 and hypertensive patients without COVID-19, with 30 individuals in each group. Cardiorespiratory response parameters were assessed before and after performing the 6MWT. QoL was evaluated using the SF-36 at baseline and again at 3 months. Results: Hypertensive patients who recovered from COVID-19 showed significant improvements, including reduced post-exercise HR, SBP, SpO₂, RPE, and leg fatigue, as well as increased 6MWT distance and enhanced QoL compared to baseline (p < 0.05). These parameters improved and returned to levels similar to those of hypertensive patients without COVID-19 by the 3-month follow-up. Conclusions: Hypertensive patients who have recovered from COVID-19 can achieve cardiorespiratory fitness and QoL levels comparable to those of hypertensive individuals who did not contract COVID-19 by the 3-month follow-up. Full article

Anatomic and functional changes in the pelvic floor muscles (PFMs) have been associated with stress urinary incontinence (SUI). The aim of this study is to compare cough-induced contraction response time and PFM strength in women with and without SUI. This cross-sectional study evaluated 40 women (20 with and 20 without SUI) aged 20 to 60 years. PFM strength was measured using a vaginal dynamometer. The cough signal was captured using an accelerometer, and activity of the right external oblique muscle was measured using surface electromyography. All signals were synchronized and recorded using the same signal acquisition module. Analysis of covariance (ANCOVA) with the Bonferroni post hoc test was used to compare the dynamometric data between groups (control and SUI). No significant differences were found between groups regarding variables related to PFM strength, but significant differences were found for activation time of the PFMs (F = 59.42, p < 0.0001, η_p² = 0.76), activation time of the external oblique muscle (F = 6.55, p = 0.004, η_p² = 0.26), and cough pulse time (F = 3.32, p = 0.04, η_p² = 0.15). Women with stress urinary have a delayed cough-induced contraction response of the pelvic floor muscles, but no difference in the contraction force of these muscles was found in comparison to women without stress urinary incontinence. Full article

Background: Entrusted budgets were introduced as part of the primary healthcare (PHC) system in Poland in July 2022. This initiative aimed to increase the role of PHC and enhance the accessibility of diagnostic services and specialist consultations/advice for patients. Methods: Data from the National Health Fund (NHF) databases regarding contracts between the NHF and healthcare providers in the field of PHC from 2022 to 2025 were analyzed. The share of contracts with entrusted budgets in the total number of PHC physician contracts was estimated in individual voivodships, as well as in counties, using the example of the Małopolskie Voivodship. It was assessed whether there were significant differences between voivodships and counties as well as the pace of implementation of the new solution. Results: Only 43.1% of PHC physicians have signed contracts with the NHF for coordinated care services for 2025, with this percentage varying significantly between voivodships, ranging from 24.8% in Opolskie Voivodship to 66.3% in Lubelskie Voivodship (p < 0.0001). For the vast majority of voivodships, no statistically significant increase in the share of service providers was demonstrated in the period from 2022 to 2025. Access to services between counties is also highly varied (from 10.0% to 76.5%), although the differences were not statistically significant (p = 0.217). Conclusions: The results indicate regional and local inequalities in access to services. It is necessary to implement incentive mechanisms within the contracting of health services between the NHF and providers that will ensure equal access to PHC services within entrusted budgets for all patients. The range of available services should be equal regardless of at which PHC facility a patient is registered. The current regulations concerning entrusted budgets, including the voluntary involvement of service providers, are not sufficient. Full article