Search Results (640)

Introduction: Myotonia is a rare neuromuscular condition characterized by impaired muscle relaxation. In this study, we provide normative values for clinical tests related to myotonia in the Hungarian population and compare them to patients with myotonic dystrophy type 1 (DM1). Methods: Relaxation tests (10 eye openings, tongue extension, and palm openings), handgrip strength, and the nine-hole peg test were conducted on 139 healthy individuals and 31 patients with DM1. Results: We observed non-significant declines in handgrip strength and relaxation tests with age (p < 0.05). Significant differences were found between controls (n:139) and patients with DM1 (n = 31) in all tests (p < 0.05). Sex differences were noted in the healthy population: men (n:68/139) had stronger handgrip (mean of men 42.45 ± 1.15 vs. women 24.3 ± 0.9) and slower relaxation tests (mean of eye openings in men 3.6 ± 0.2 vs. in women 4.2 ± 0.2, tongue extensions in men 3.7 ± 0.2 vs. in women 4.2 ± 0.2, palm openings in men 4 ± 0.2 vs. in women 4.9 ± 0.2 However, these differences were not present among patients with DM1. Discussion: Normal values for relaxation tests across different age groups were established. These results might be useful for further clinical investigations. Our study supports the usage of averages of healthy population instead of age groups of relaxation tests and their clinical relevance in the evaluation of patients with myotonia. Full article

Background/Objectives: Urinary incontinence (UI), defined as the involuntary loss of urine, is common among female athletes. As more women engage in competitive sports, numerous studies have explored UI in young, nulliparous, and physically active women. The objectives of this study were (i) to analyze the prevalence, severity, and characteristics of UI in professional nulliparous female soccer players and (ii) to compare the status of the pelvic floor muscles (PFMs) between professional soccer players and physically active young women. Methods: This descriptive cross-sectional study included professional soccer players (n = 18) and physically active women (n = 14). UI was assessed using the ICIQ-SF questionnaire, and PFM function was evaluated through intracavitary examination using the PERFECT method. Additional data were collected on body composition and on urinary, bowel, and sexual health. Results: UI affected 35.7% of physically active women and 50% of professional soccer players. Stress urinary incontinence (SUI) was the most common type, present in 100% of affected soccer players and 60% of affected active women. The severity of UI was mostly mild, with no significant differences between groups. PFM assessment revealed deficiencies in control, relaxation, endurance, and rapid contractions, as well as difficulties performing an effective perineal locking (PL) maneuver during increased intra-abdominal pressure. Conclusions: These findings highlight the need for targeted programs focused on strengthening and educating athletes about their PFMs, aiming to prevent UI and improve both performance and quality of life. The study reinforces the importance of preventive strategies for pelvic floor health in sports. Full article

Background: Sarcopenia is a progressive muscle disease that compromises mobility and quality of life in older adults. Although dual-energy X-ray absorptiometry (DXA) is the standard for assessing Appendicular Lean Mass Index (ALMI), it is costly and often inaccessible. This study aims to develop machine learning models using anthropometric measurements to predict low ALMI for the diagnosis of sarcopenia. Methods: A cross-sectional study was conducted on 183 Mexican adults (67.2% women and 32.8% men, ≥60 years old). ALMI was measured using DXA, and anthropometric data were collected following the International Society for the Advancement of Kinanthropometry (ISAK) protocols. Predictive models were developed using Logistic Regression (LR), Decision Trees (DTs), Random Forests (RFs), Artificial Neural Networks (ANNs), and LASSO regression. The dataset was split into training (70%) and testing (30%) sets. Model performance was evaluated using classification performance metrics and the area under the ROC curve (AUC). Results: ALMI indicated strong correlations with BMI, corrected calf girth, and arm relaxed girth. Among models, DT achieved the best performance in females (AUC = 0.84), and ANN indicated the highest AUC in males (0.92). Regarding the prediction of low ALMI, specificity values were highest in DT for females (100%), while RF performed best in males (92%). The key predictive variables varied depending on sex, with BMI and calf girth being the most relevant for females and arm girth for males. Conclusions: Anthropometry combined with machine learning provides an accurate, low-cost approach for identifying low ALMI in older adults. This method could facilitate sarcopenia screening in clinical settings with limited access to advanced diagnostic tools. Full article

Medical Infrared Thermography (MIT) is a safe, non-invasive technique for assessing temperature changes on the skin’s surface that may reflect pathological processes in the underlying tissues. In temporomandibular joint disorders (TMDs), which are often associated with reduced mobility and muscle overactivity, tissue metabolism and blood flow may be diminished, resulting in localized hypothermia. Aim: The purpose of this study was to evaluate muscle tone in the masseter, suprahyoid, and sternocleidomastoid muscles following the application of two types of occlusal splints, a Michigan splint and a double repositioning splint, based on temperature changes recorded using a Fluke Ti401 PRO thermal imaging camera. Materials and Methods: Sixty dental students diagnosed with TMDs were enrolled in this study. After applying the inclusion and exclusion criteria, participants were randomly assigned to one of two groups. Group M received a Michigan splint, while group D was treated with a double repositioning splint. Results: The type of occlusal splint influenced both temperature distribution and muscle tone. In the double repositioning splint group, temperature decreased by approximately 0.8 °C between T1 and T3, whereas in the Michigan splint group, temperature increased by approximately 0.7 °C over the same period. Conclusions: Occlusal splint design has a measurable impact on temperature distribution and muscle activity. The double repositioning splint appears to be more effective in promoting short-term muscle relaxation and may provide relief for patients experiencing muscular or myofascial TMD symptoms. Full article

G-protein-coupled receptors (GPCRs) are vital transmembrane proteins that regulate a wide range of physiological processes by transmitting extracellular signals into intracellular responses. Among them, the β2-adrenergic receptor (β2-AR) plays a central role in bronchodilation, smooth muscle relaxation, and cardiovascular modulation, making it a key therapeutic target for diseases such as asthma, chronic obstructive pulmonary disease (COPD), and hypertension. This study explores the potential of natural bioactive compounds like ephedrine, quercetin, catechin, and resveratrol as alternative ligands for β2-AR through molecular docking analysis. Using AutoDock 4.6, these compounds were docked with the binding site of the β2-AR (PDB ID: 2RH1), and their binding affinities and interaction map were evaluated. Results showed that all compounds exhibited favorable binding energies and stable interactions with key receptor residues, with quercetin demonstrating the highest affinity. The findings suggest that these natural compounds may serve as promising leads for the development of safer, plant-derived modulators of β2-AR, supporting the role of computational approaches in natural product-based drug discovery. However, as docking cannot determine functional activity, these findings should be interpreted as preliminary and require experimental validation. Full article

Primary dysmenorrhea (PD) is characterized by lower abdominal spasms and painful cramps during menstruation in females with a normal pelvic anatomy. Cymbopogon citratus (DC.) Stapf, commonly known as lemongrass, is consumed in the form of herbal tea around the world. It has been traditionally used for menstrual disorders in several communities. This study aims to evaluate the traditional use of C. citratus for its efficacy in alleviating the symptoms of PD. C. citratus extract (CcE) was chemically characterized using HPLC and GCMS, which indicated the presence of several phenolic compounds and long-chain fatty acids. The anti-inflammatory activity of CcE was assessed by COX-I, COX-II, and 5-LOX enzyme inhibition with IC₅₀ values of 143.7, 91.7, and 61.5 µg/mL, respectively, and showed good total antioxidant capacity and free radical scavenging activity. PD was induced in female Wistar rats by administering estradiol valerate followed by oxytocin to induce PD symptoms. CcE efficacy was assessed at 30, 100, and 300 mg/kg concentrations and compared with ibuprofen. CcE 300 mg/kg reduced abdominal contortions and inflammation in the rat uterus. The inflammatory (COX-II, TNFα and IL-10) and oxidative stress (TAC, TOS, MDA and SOD) markers in uterine tissue homogenate were also improved. An in vivo analgesic assessment through hot-plate, tail-flick, and acetic acid-induced writhing assays showed good analgesic activity by CcE, while ex vivo experiments described tocolytic effects in rat uterine muscles. CcE alleviates PD by its antioxidant, anti-inflammatory, analgesic, and tocolytic effects. Full article

Monitoring forearm muscle contraction force in home-based rehabilitation remains challenging. Electromyography (EMG), as a standard technique, is considered impractical and complex for independent use by patients at home, which poses a risk of device misattachment and inaccurate recorded data. Considering the muscle-related modality, several studies have demonstrated an excellent correlation between stretch sensors and EMG, which provides significant potential for addressing the monitoring issue at home. Additionally, due to its flexible nature, it can be attached to the finger, which facilitates the logging of the kinematic mechanisms of a finger. This study proposes a method for estimating forearm muscle contraction in a cylinder grasping environment during home-based rehabilitation using a stretch-sensor glove. This study employed support vector machine (SVM), multi-layer perceptron (MLP), and random forest (RF) to construct the estimation model. The root mean square (RMS) of the EMG signal, representing the muscle contraction force, was collected from 10 participants as the target learning for the stretch-sensor glove. This study constructed an experimental design based on a home-based therapy protocol known as the graded repetitive arm supplementary program (GRASP). Six cylinders with varying diameters and weights were employed as the grasping object. The results demonstrated that the RF model achieved the lowest root mean square error (RMSE) score, which differed significantly from the SVM and MLP models. The time series waveform comparison revealed that the RF model yields a similar estimation output to the ground truth, which incorporates the contraction–relaxation phases and the muscle’s contraction force. Additionally, despite the subjectivity of the participants’ grasping power, the RF model could produce similar trends in the muscle contraction forces of several participants. Utilizing a stretch-sensor glove, the proposed method demonstrated great potential as an alternative modality for monitoring forearm muscle contraction force, thereby improving the practicality for patients to self-implement home-based rehabilitation. Full article

Determining the technological quality of fresh meat pieces is essential in the meat industry to ensure the production of high-quality products. For this purpose, nuclear magnetic resonance (NMR) is a non-destructive and non-invasive technique that appears as an alternative to traditional methodologies. The objective of this work is to determine the potential of magnetic resonance imaging (MRI) and time-domain (TD-NMR) relaxometry for determining the physicochemical characterization of fresh hams with different industrial destinations (both fresh and cured products, such as dry-cured ham). For this study, the biceps femoris, semimembranosus, and semitendinosus muscles of 20 fresh hind legs from white pigs, classified into four categories according to their fat content, were analyzed. The semitendinosus muscle was selected as a model, and positive and negative correlations were obtained between different physicochemical parameters and the longitudinal (T1) and transverse (T2) relaxation times obtained by MRI and TD-NMR. Regression models using T1 and T2 were also developed to predict the muscle water-holding capacity (WHC) and drip loss, using high, medium, and low magnetic field NMR (R² > 0.80). Therefore, MRI and TD-NMR could be considered as highly suitable and accurate non-destructive techniques for the WHC determination in the meat industry. Full article

Background: Pain manifestations as well as increased muscle tone and stiffness noted in the course of delayed-onset muscle soreness (DOMS) are reflected in altered values of the biomechanical and visco-elastic parameters of muscles. This study aimed to compare the effects of soft tissue mobilization with foam rolling and percussive massage on symptoms of DOMS induced by a standardized muscle fatigue protocol. Methods: Healthy volunteers (n = 60) were divided into three groups: FR group—foam rolling (n = 20), PM group—percussive massage (n = 20) and CON group—control/passive rest (n = 20). The fatigue protocol for the gastrocnemius muscle was carried out for development of DOMS in subsequent days. Therapeutic procedures were applied to participants for 3 consecutive days. The results of therapy were assessed by means of myotonometry, performed five times (before, three times during the treatment procedure, and after the end of the procedure). Results: Foam rolling significantly reduced the onset and duration of increased muscle tone (p = 0.006) and stiffness (p < 0.001), unlike percussive massage. The control group exhibited higher tone and stiffness after 48 h, at the peak of DOMS-related pain symptoms. Only foam rolling improved elasticity (decrement, p < 0.001), while visco-elastic properties (relaxation, creep) varied inversely with tone and stiffness. Foam rolling led to significantly lower stiffness (day 2) and reduced decrement and relaxation (day 4) compared to the control. Neither therapy was more effective than passive rest for pain relief during the observation period. Conclusions: Foam rolling and percussive massage accelerate recovery of muscle tone, stiffness, and elasticity after DOMS as compared to passive rest but offer no added benefit for pain relief. Full article

Objectives: Muscular dysfunction of the cervical spine is the most likely cause of somatosensory tinnitus and dizziness. Some patients can modulate their tinnitus through movement or palpation. This study aimed to investigate the effect of manual therapy on muscle pressure pain, range of motion in the cervical spine, and tinnitus and dizziness. Methods: A pilot randomized controlled trial with a waiting-group design was conducted in a university hospital setting. Participants in the intervention group received manual therapy to the head and neck region combined with stretching exercises and muscle relaxation techniques such as releasing tense muscles and myofascial trigger point therapy involving muscle and connective tissue techniques. The primary and secondary outcome measures were pressure pain, tinnitus modulation by head and neck muscles, and range of motion of the cervical spine. Tinnitus and dizziness were assessed before and after the intervention using the Tinnitus Handicap Inventory and the Dizziness Handicap Inventory. Results: After the intervention, significant differences were observed in pressure pain, tinnitus modulation, and range of motion as well as the Tinnitus Handicap Inventory (U = 644; p < 0.001) and the Dizziness Handicap Inventory (U = 133.5; p = 0.010), favoring the intervention group. Conclusions: The results demonstrate that manual therapy significantly altered pressure pain in the head and neck muscles as well as symptoms such as tinnitus and dizziness in the intervention group. Manual therapy may be beneficial in treating cervicogenic somatosensory tinnitus, provided that other potential causes such as otorhinolaryngological pathology have been ruled out. Full article

Aim: To assess the acute effects of proprioceptive neuromuscular facilitation (PNF), stretching was applied to the hamstring muscles to evaluate deep cervical flexor endurance. Potential variables correlating with endurance adaptations were examined. Methods: This randomized controlled trial performed between September 2023 and June 2024 included healthy female university students aged 18–25 years. Participants were randomly assigned to either the control or the PNF group. Variables included age, height, weight, body mass index, Beighton score, hamstring flexibility, and deep cervical flexor muscle endurance; correlations between changes in hamstring flexibility and DCF endurance were explored. Hamstring flexibility was assessed using the Passive Knee Extension Test, and deep cervical flexor endurance was assessed using the Cranio-Cervical Flexion Test. The PNF group received hold–relax exercises while controls did not receive any intervention. Results: The study included 32 control participants and 32 individuals in the PNF group. The PNF group was marginally but significantly older than the control group [22 (21–23) vs. 21 (21–22); p = 0.038]. At baseline, the PNF group showed greater hamstring flexibility (p = 0.010). Both groups showed significant improvements in hamstring flexibility (p < 0.001 for both), but the improvement in the PNF recipients was far greater (p < 0.001). Regarding deep neck flexor endurance, no significant difference was observed between the groups at baseline (p = 0.958) or in final measurements (p = 0.244), although both groups showed significant improvements from baseline (p < 0.001 for both). There were no significant correlations between the change in deep neck flexor endurance and any of the examined variables. Conclusions: Our study found that a single session of PNF stretching significantly improved hamstring flexibility but did not immediately enhance deep neck flexor endurance. This emphasizes the need for further research into longer-term interventions to assess whether interventions on hamstring flexibility can improve cervical function. Full article

Background. Sleep disorders are a group of conditions that disrupt normal sleep patterns and are among the most common clinical challenges faced today. An innovative device that employs nanotechnology to deliver beneficial effects on the human body is the Taopatch^® (Tao Technologies, Vedelago, Italy). This study aims to assess the effectiveness of such nanotechnology-based devices in improving sleep quality. Methods. This study included only female participants, as a review of the literature indicated that sleep disorders are more prevalent in women than in men. A total of 30 subjects (with a mean age of 44.8 ± 3.44 years) were randomly divided into two groups: an experimental group and a control group. Sleep quality was evaluated three times throughout the study for each participant using the Pittsburgh Sleep Quality Index (PSQI). The Taopatch^® devices were applied using a specialized pillow. Results. The experimental group showed significantly better sleep quality (p < 0.001) compared to the control group. Conclusions. Our findings suggest that the application of the Taopatch^® has a positive impact on sleep quality by optimizing posture, aligning the cervical spine, and promoting muscle relaxation. This device uses advanced nanotechnology to enhance various physiological functions, contributing to better overall well-being. Full article

The creation of quick-reacting electrically conductive polymers for use as actuators driven by low electrical currents is now seen as an important issue. Enhancing the electrical conductivity of hydrogels through the incorporation of conductive fillers, like salts, can reduce the necessary actuating voltage. However, several important questions arise about how the type of salt chosen and its concentration will affect not only the activation efficiency of the actuators but also the structure of the hydrogels utilized. In this study, to enhance the electrical conductivity of the hydrogel and lower the necessary activation voltage of the hydrogel actuators, lithium chloride (LiCl) and sodium chloride (NaCl) were incorporated as conductive fillers into the polyvinyl alcohol (PVA) polymer matrix. To determine the deformation of actuators, as well as the activation and relaxation times and efficiencies during activation, linear actuators capable of being activated through extension/contraction (swelling/shrinking) cycles were developed and examined based on the LiCl/NaCl content, applied voltage, and frequency. The main finding is that the required actuating voltage was lowered by up to 20 V by adding an equal mass of salt in relation to the PVA mass content. With a load of around 20 kPa, it was observed that the extension deformation for PVA/NaCl-based actuators can achieve 75%, while in contraction deformation, can reach 17%. Additionally, for the PVA/LiCl-based actuators, the extension deformation can reach 87%, while during contraction deformation, it can reach 22%. The degree of swelling in the PVA/NaCl hydrogels was generally less than that in the PVA/LiCl hydrogels, which was associated with the finding that the actuators prepared from PVA/NaCl hydrogels delivered an output that was 10–15% lower than those made from PVA/LiCl hydrogels across different testing cycles. Furthermore, adding salt increases the degree of crosslinking, which can explain why increased crosslinking leads to reduced deformation when exposed to AC voltage. These actuators can find extensive use in soft robotics, artificial muscles, medical applications, and aerospace industries. Full article

Background: This study aimed to investigate the acute changes in muscle and tendon viscoelastic properties in response to a progressive treadmill VO₂max test among professional male soccer players. Methods: Bilateral assessments at five sites—the Achilles tendon (AT), biceps femoris, semitendinosus, rectus femoris (RF), and sternocleidomastoid (SCM)—measured tone (oscillation frequency), dynamic stiffness, logarithmic decrement (elasticity), stress relaxation time, and creep. Each site was probed five times and values averaged. Repeated-measures ANOVA (Time × Side) with Bonferroni correction tested pre- to post-exercise changes; Pearson’s r examined associations with VO₂max. Results: Significant Time effects (all p < 0.05) were observed for RF frequency (η_p² = 0.226), RF creep (η_p² = 0.144), AT stiffness (η_p² ≈ 0.035), AT frequency (η_p² = 0.035), and SCM frequency (η_p² = 0.037). Post-exercise, right AT stiffness fell by 65 ± 14 N/m (p = 0.015), while left AT stiffness rose by 22 ± 9 N/m (p = 0.015). RF stiffness decreased by 28 ± 6 N/m (p < 0.001) and tone by 1.2 ± 0.3 Hz (p < 0.001), with creep (+0.08 ± 0.02; p < 0.001) and relaxation time (+1.5 ± 0.7 ms; p < 0.001) increasing. SCM tone declined by 0.8 ± 0.4 Hz (p = 0.010). Baseline RF properties—frequency (r = −0.597), stiffness (r = −0.59), relaxation time (r = 0.53), and creep (r = 0.48)—correlated moderately with VO₂max (all p < 0.05). Conclusions: These findings suggest that viscoelastic adaptations to exhaustive aerobic exercise are tissue- and side-specific, and that rectus femoris viscoelastic properties may serve as potential indicators of endurance readiness. Full article

G-protein-coupled receptors (GPCRs) are a group of various membrane proteins that mediate essential physiological processes by translating extracellular signals into intracellular responses. The β2-Adrenergic Receptor (β2-AR), a key GPCR, plays a critical role in smooth muscle relaxation, bronchodilation, and cardiovascular function, making it an important therapeutic target for diseases such as asthma and hypertension. Diketopiperazines (DPKs), as cyclic peptides, have shown promise as scaffolds for inhibiting protein interactions and modulating receptor activity, offering a potential alternative to traditional small-molecule inhibitors with reduced side effects. In this study, five DPK derivatives were selected from the PubChem database and evaluated for their binding affinity to the 3D structure of β2-AR (PDB ID = 2RH1) through molecular docking studies using AutoDock 4.6 and MGLTools. The binding energy and hydrogen bond formation of each compound were evaluated to determine their interaction efficiency. Among the compounds, tryptophan-proline diketopiperazine (compound 3) exhibited the highest binding affinity with a binding energy of −5.89 kcal/mol. This enhanced interaction is attributed to the aromatic nature of tryptophan, which promotes strong π-π stacking interactions, and the rigidity of proline, which optimally fits within the receptor’s binding pocket. Hydrophobic interactions further stabilized the complex. These findings highlight compound 3 as a promising β2-AR modulator, providing valuable insights for the design of peptide-based inhibitors targeting β2-AR-related pathologies. Full article