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Fulltext Prevalence of Sarcocystis spp. in rodents in Peninsular Malaysia

Ambu, Stephen, Yin, Evelyn Synn Yeoh, Joon, Wah Mak, Chakravarthi, Srikumar

International e-Journal of Science, Medicine & Education, 2011;5(2):29-38.
MyJurnal

The aim of the study was to assess the prevalence of Sarcocystis infection in wild and peri-urban rodents in some states in Peninsular Malaysia. The thigh muscle from these rodents were formalin preserved, sectioned and stained with hematoxylin and eosin and examined under light microscopy. Of the 146 muscle tissue examined only 73 were positive for Sarcocystis infection.
Morphological identification showed the presence of some new morphological types to be present. Different species of Sarcocystis were seen in the sections but more extensive studies are needed to identify them to species level.

Matched MeSH terms: Muscle, Skeletal
Fulltext The effects of plyometric training on the muscle physical changes among long jumpers

Prabhu Ragawan, Ruaibah Yazani Tengah

Jurnal Sains Sukan & Pendidikan Jasmani, 2018;7(1):62-70.
MyJurnal

This study aim to examine the effectiveness of plyometric training on muscle physical changes. 24 long jumpers under 12 year old from Cameron Highland were involved in this study. 12 participants were in the control group and another 12 were assigned into treatment group. The training program was conducted twice a week for six weeks. Girth of thigh and calf muscles measurement were conducted during pre-test and post-test. The data were analyzed using descriptive analysis and two-way ANOVA test to determine the mean differences between groups, trial period and interaction of group and trial period. The findings showed that calf and thigh circumference show an improvement for both treatment and control group, in which the treatment group had gained significantly higher achievement. The two-way ANOVA test showed significant differences in enlargement of thigh muscle and calf muscle diameter between groups and trial period. As a conclusion, the plyometric exercises increased circumference of the thigh muscles and calf muscles among long jumpers. The implication of the study is that the proper plyometric training with an appropriate load for primary school athletes need to be implemented to achieve peak performance.

Matched MeSH terms: Muscle, Skeletal
Fulltext The effect of hand grip strength and trunk rotation strength on throwing ball velocity

Rozella Ab Razak, Kee, Kang Mea, Raja Nurul Jannat Raja Hussain, Nur Atikah Mohamed Kassim, Nuraimi Othman

Movement Health & Exercise, 2018;7(1):89-98.
MyJurnal

Throwing ball velocity is one of the indicators that determine softball
performance. However, most of the training on throwing only focused on the
major muscles and they neglected the assisted muscles such as hand grip and
trunk rotation muscles that also crucial in improving the throwing
performance. Therefore, the purpose of this study is to identify the effect of
hand grip strength training, and trunk rotation strength training towards the
throwing ball velocity among female collegiate softball players. 54 female
collegiate softball players were equally divided into three training groups
which are hand grip strength training group (HG), trunk rotation strength
training group (TR), and basic strength training group (CG). All the groups
performed the same basic strength training program with different additional
strength training according to the group`s treatment. Each group trained 3
days per week for 6 weeks. Throwing ball velocity was assessed before
(pretest) and after (posttest) the 6 weeks training program via one-way
between groups analysis of variance (ANOVA) to compare the mean gained
score in throwing ball velocity between each group. The result shows that all
group significantly differences in throwing ball velocity (p

Matched MeSH terms: Muscle, Skeletal
Fatigue effect on cross-talk in mechanomyography signals of extensor and flexor forearm muscles during maximal voluntary isometric contractions

Mohamad Ismail MR, Lam CK, Sundaraj K, Rahiman MHF

J Musculoskelet Neuronal Interact, 2021 12 01;21(4):481-494.
PMID: 34854387

OBJECTIVE: This paper presents the analyses of the fatigue effect on the cross-talk in mechanomyography (MMG) signals of extensor and flexor forearm muscles during pre- and post-fatigue maximum voluntary isometric contraction (MVIC).
METHODS: Twenty male participants performed repetitive submaximal (60% MVIC) grip muscle contractions to induce muscle fatigue and the results were analyzed during the pre- and post-fatigue MVIC. MMG signals were recorded on the extensor digitorum (ED), extensor carpi radialis longus (ECRL), flexor digitorum superficialis (FDS) and flexor carpi radialis (FCR) muscles. The cross-correlation coefficient was used to quantify the cross-talk values in forearm muscle pairs (MP1, MP2, MP3, MP4, MP5 and MP6). In addition, the MMG RMS and MMG MPF were calculated to determine force production and muscle fatigue level, respectively.
RESULTS: The fatigue effect significantly increased the cross-talk values in forearm muscle pairs except for MP2 and MP6. While the MMG RMS and MMG MPF significantly decreased (p<0.05) based on the examination of the mean differences from pre- and post-fatigue MVIC.
CONCLUSION: The presented results can be used as a reference for further investigation of cross-talk on the fatigue assessment of extensor and flexor muscles' mechanic.

Matched MeSH terms: Muscle, Skeletal
Fulltext Hepatocellular carcinoma with disseminated skeletal muscle metastasis

Rahim EA, Noh MS, Ngah NA, Suraini MS, Yusof MM

Acta Radiol Open, 2017 Jul;6(7):2058460117716705.
PMID: 28811928 DOI: 10.1177/2058460117716705

Hepatocellular carcinoma (HCC) is the commonest primary tumor of the liver and carries a poor prognosis when diagnosed late or left untreated. Treatment relies heavily on the stage of the tumor when diagnosed. Extrahepatic metastasis is known to occur; these are mainly reported via autopsy studies or isolated case reports. Knowledge of extrahepatic metastasis is crucial in order to avoid unnecessary surgery. We report a rare case of a patient at our center, diagnosed to have HCC, who underwent treatment successfully, only to come back with extrahepatic metastasis to the skeletal muscles.

Matched MeSH terms: Muscle, Skeletal
Fulltext Mechanomyography and Torque during FES-Evoked Muscle Contractions to Fatigue in Individuals with Spinal Cord Injury

Mohamad NZ, Hamzaid NA, Davis GM, Abdul Wahab AK, Hasnan N

Sensors (Basel), 2017 Jul 14;17(7).
PMID: 28708068 DOI: 10.3390/s17071627

A mechanomyography muscle contraction (MC) sensor, affixed to the skin surface, was used to quantify muscle tension during repetitive functional electrical stimulation (FES)-evoked isometric rectus femoris contractions to fatigue in individuals with spinal cord injury (SCI). Nine persons with motor complete SCI were seated on a commercial muscle dynamometer that quantified peak torque and average torque outputs, while measurements from the MC sensor were simultaneously recorded. MC-sensor-predicted measures of dynamometer torques, including the signal peak (SP) and signal average (SA), were highly associated with isometric knee extension peak torque (SP: r = 0.91, p < 0.0001), and average torque (SA: r = 0.89, p < 0.0001), respectively. Bland-Altman (BA) analyses with Lin's concordance (ρC) revealed good association between MC-sensor-predicted peak muscle torques (SP; ρC = 0.91) and average muscle torques (SA; ρC = 0.89) with the equivalent dynamometer measures, over a range of FES current amplitudes. The relationship of dynamometer torques and predicted MC torques during repetitive FES-evoked muscle contraction to fatigue were moderately associated (SP: r = 0.80, p < 0.0001; SA: r = 0.77; p < 0.0001), with BA associations between the two devices fair-moderate (SP; ρC = 0.70: SA; ρC = 0.30). These findings demonstrated that a skin-surface muscle mechanomyography sensor was an accurate proxy for electrically-evoked muscle contraction torques when directly measured during isometric dynamometry in individuals with SCI. The novel application of the MC sensor during FES-evoked muscle contractions suggested its possible application for real-world tasks (e.g., prolonged sit-to-stand, stepping,) where muscle forces during fatiguing activities cannot be directly measured.

Matched MeSH terms: Muscle, Skeletal
Fulltext Targeting myomiRs by tocotrienol-rich fraction to promote myoblast differentiation

Razak AM, Khor SC, Jaafar F, Karim NA, Makpol S

Genes Nutr, 2018;13:31.
PMID: 30519366 DOI: 10.1186/s12263-018-0618-2

Background: Several muscle-specific microRNAs (myomiRs) are differentially expressed during cellular senescence. However, the role of dietary compounds on myomiRs remains elusive. This study aimed to elucidate the modulatory role of tocotrienol-rich fraction (TRF) on myomiRs and myogenic genes during differentiation of human myoblasts. Young and senescent human skeletal muscle myoblasts (HSMM) were treated with 50 μg/mL TRF for 24 h before and after inducing differentiation.
Results: The fusion index and myotube surface area were higher (p

Matched MeSH terms: Muscle, Skeletal
Fulltext Effects of releasing ankle joint during electrically evoked cycling in persons with motor complete spinal cord injury

Hamdan PNF, Hamzaid NA, Hasnan N, Abd Razak NA, Razman R, Usman J

Sci Rep, 2024 Mar 18;14(1):6451.
PMID: 38499594 DOI: 10.1038/s41598-024-56955-w

Literature has shown that simulated power production during conventional functional electrical stimulation (FES) cycling was improved by 14% by releasing the ankle joint from a fixed ankle setup and with the stimulation of the tibialis anterior and triceps surae. This study aims to investigate the effect of releasing the ankle joint on the pedal power production during FES cycling in persons with spinal cord injury (SCI). Seven persons with motor complete SCI participated in this study. All participants performed 1 min of fixed-ankle and 1 min of free-ankle FES cycling with two stimulation modes. In mode 1 participants performed FES-evoked cycling with the stimulation of quadriceps and hamstring muscles only (QH stimulation), while Mode 2 had stimulation of quadriceps, hamstring, tibialis anterior, and triceps surae muscles (QHT stimulation). The order of each trial was randomized in each participant. Free-ankle FES cycling offered greater ankle plantar- and dorsiflexion movement at specific slices of 20° crank angle intervals compared to fixed-ankle. There were significant differences in the mean and peak normalized pedal power outputs (POs) [F(1,500) = 14.03, p

Matched MeSH terms: Muscle, Skeletal
Fulltext A New Approach to Noninvasive-Prolonged Fatigue Identification Based on Surface EMG Time-Frequency and Wavelet Features

Jamaluddin FN, Ibrahim F, Ahmad SA

J Healthc Eng, 2023;2023:1951165.
PMID: 36756137 DOI: 10.1155/2023/1951165

In sports, fatigue management is vital as adequate rest builds strength and enhances performance, whereas inadequate rest exposes the body to prolonged fatigue (PF) or also known as overtraining. This paper presents PF identification and classification based on surface electromyography (EMG) signals. An experiment was performed on twenty participants to investigate the behaviour of surface EMG during the inception of PF. PF symptoms were induced in accord with a five-day Bruce Protocol treadmill test on four lower extremity muscles: the biceps femoris (BF), rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL). The results demonstrate that the experiment successfully induces soreness, unexplained lethargy, and performance decrement and also indicate that the progression of PF can be observed based on changes in frequency features (ΔF med and ΔF mean) and time features (ΔRMS and ΔMAV) of surface EMG. This study also demonstrates the ability of wavelet index features in PF identification. Using a naïve Bayes (NB) classifier exhibits the highest accuracy based on time and frequency features with 98% in distinguishing PF on RF, 94% on BF, 9% on VL, and 97% on VM. Thus, this study has positively indicated that surface EMG can be used in identifying the inception of PF. The implication of the findings is significant in sports to prevent a greater risk of PF.

Matched MeSH terms: Muscle, Skeletal
Fulltext Mechanomyographic parameter extraction methods: an appraisal for clinical applications

Ibitoye MO, Hamzaid NA, Zuniga JM, Hasnan N, Wahab AK

Sensors (Basel), 2014;14(12):22940-70.
PMID: 25479326 DOI: 10.3390/s141222940

The research conducted in the last three decades has collectively demonstrated that the skeletal muscle performance can be alternatively assessed by mechanomyographic signal (MMG) parameters. Indices of muscle performance, not limited to force, power, work, endurance and the related physiological processes underlying muscle activities during contraction have been evaluated in the light of the signal features. As a non-stationary signal that reflects several distinctive patterns of muscle actions, the illustrations obtained from the literature support the reliability of MMG in the analysis of muscles under voluntary and stimulus evoked contractions. An appraisal of the standard practice including the measurement theories of the methods used to extract parameters of the signal is vital to the application of the signal during experimental and clinical practices, especially in areas where electromyograms are contraindicated or have limited application. As we highlight the underpinning technical guidelines and domains where each method is well-suited, the limitations of the methods are also presented to position the state of the art in MMG parameters extraction, thus providing the theoretical framework for improvement on the current practices to widen the opportunity for new insights and discoveries. Since the signal modality has not been widely deployed due partly to the limited information extractable from the signals when compared with other classical techniques used to assess muscle performance, this survey is particularly relevant to the projected future of MMG applications in the realm of musculoskeletal assessments and in the real time detection of muscle activity.

Matched MeSH terms: Muscle, Skeletal/physiopathology*
Muscle synergies during incremental rowing VO2max test of collegiate rowers and untrained subjects

Shaharudin S, Agrawal S

J Sports Med Phys Fitness, 2016 Sep;56(9):980-9.
PMID: 25732319

BACKGROUND: The purpose of this study was to evaluate the muscle synergies during incremental rowing VO2 max Test of collegiate rowers and untrained subjects. As a power endurance sport, high aerobic capacity was one of the determinants of rowing performance. The modulation of muscle recruitment patterns following specific physiological demands was an indication of the robustness of muscle synergies composition which was overlooked in previous studies.
METHODS: Ten male collegiate rowers and physically active untrained subjects were recruited. Muscle synergies were extracted from 16 rowing-specific muscles using Principal Component Analysis with varimax rotation. Incremental rowing VO2 max Test was performed on slides ergometer (SE). Rowing performance and physiological variables were analyzed.
RESULTS: Rowers exerted greater power output, more energy expenditure and better rowing economy compared to untrained subjects. Rowers preferred to row slower with longer strokes compared to the untrained subjects. Three muscle synergies with high indices of similarity of waveform patterns were extracted in both groups. Significant association was found between muscle synergies and rowing economy.
CONCLUSIONS: The findings of this study showed that muscle synergies were robust during aerobic-dominant activity for collegiate rowers and untrained subjects. Rowers and coaches could utilize the findings by emphasizing on muscle coordination training, which may enhance the rowing economy.

Matched MeSH terms: Muscle, Skeletal/physiology*
Role of nitric oxide in skeletal muscle glucose uptake during exercise

Hong YH, Betik AC, McConell GK

Exp Physiol, 2014 Dec 1;99(12):1569-73.
PMID: 25192731 DOI: 10.1113/expphysiol.2014.079202

Nitric oxide is produced within skeletal muscle fibres and has various functions in skeletal muscle. There is evidence that NO may be essential for normal increases in skeletal muscle glucose uptake during contraction/exercise. Although there have been some discrepant results, it has been consistently demonstrated that inhibition of NO synthase (NOS) attenuates the increase in skeletal muscle glucose uptake during contraction in mouse and rat muscle ex vivo, during in situ contraction in rats and during exercise in humans. The NO-mediated increase in skeletal muscle glucose uptake during contraction/exercise is probably due to the modulation of intramuscular signalling that ultimately increases glucose transporter 4 (GLUT4) translocation and is, surprisingly, independent of blood flow. In this review, we discuss the evidence for and against a role of NO in regulating skeletal muscle glucose uptake during contraction/exercise and outline the possible mechanism(s) involved. Emerging findings regarding the role of neuronal NOS mu (nNOSμ) in this process are also discussed.

Matched MeSH terms: Muscle, Skeletal/metabolism*
Analysis of crosstalk in the mechanomyographic signals generated by forearm muscles during different wrist postures

Islam A, Sundaraj K, Ahmad RB, Sundaraj S, Ahamed NU, Ali MA

Muscle Nerve, 2015 Jun;51(6):899-906.
PMID: 25204740 DOI: 10.1002/mus.24454

In this study, we analyzed the crosstalk in mechanomyographic (MMG) signals generated by the extensor digitorum (ED), extensor carpi ulnaris (ECU), and flexor carpi ulnaris (FCU) muscles of the forearm during wrist flexion (WF) and extension (WE) and radial (RD) and ulnar (UD) deviations.

Matched MeSH terms: Muscle, Skeletal/physiopathology*
Fulltext Longitudinal, lateral and transverse axes of forearm muscles influence the crosstalk in the mechanomyographic signals during isometric wrist postures

Islam MA, Sundaraj K, Ahmad RB, Sundaraj S, Ahamed NU, Ali MA

PLoS One, 2014;9(8):e104280.
PMID: 25090008 DOI: 10.1371/journal.pone.0104280

In mechanomyography (MMG), crosstalk refers to the contamination of the signal from the muscle of interest by the signal from another muscle or muscle group that is in close proximity.

Matched MeSH terms: Muscle, Skeletal/physiology*
Fulltext The effectiveness of FES-evoked EMG potentials to assess muscle force and fatigue in individuals with spinal cord injury

Ibitoye MO, Estigoni EH, Hamzaid NA, Wahab AK, Davis GM

Sensors (Basel), 2014;14(7):12598-622.
PMID: 25025551 DOI: 10.3390/s140712598

The evoked electromyographic signal (eEMG) potential is the standard index used to monitor both electrical changes within the motor unit during muscular activity and the electrical patterns during evoked contraction. However, technical and physiological limitations often preclude the acquisition and analysis of the signal especially during functional electrical stimulation (FES)-evoked contractions. Hence, an accurate quantification of the relationship between the eEMG potential and FES-evoked muscle response remains elusive and continues to attract the attention of researchers due to its potential application in the fields of biomechanics, muscle physiology, and rehabilitation science. We conducted a systematic review to examine the effectiveness of eEMG potentials to assess muscle force and fatigue, particularly as a biofeedback descriptor of FES-evoked contractions in individuals with spinal cord injury. At the outset, 2867 citations were identified and, finally, fifty-nine trials met the inclusion criteria. Four hypotheses were proposed and evaluated to inform this review. The results showed that eEMG is effective at quantifying muscle force and fatigue during isometric contraction, but may not be effective during dynamic contractions including cycling and stepping. Positive correlation of up to r = 0.90 (p < 0.05) between the decline in the peak-to-peak amplitude of the eEMG and the decline in the force output during fatiguing isometric contractions has been reported. In the available prediction models, the performance index of the eEMG signal to estimate the generated muscle force ranged from 3.8% to 34% for 18 s to 70 s ahead of the actual muscle force generation. The strength and inherent limitations of the eEMG signal to assess muscle force and fatigue were evident from our findings with implications in clinical management of spinal cord injury (SCI) population.

Matched MeSH terms: Muscle, Skeletal/physiopathology*
Effects of action observation on corticospinal excitability: Muscle specificity, direction, and timing of the mirror response

Naish KR, Houston-Price C, Bremner AJ, Holmes NP

Neuropsychologia, 2014 11;64:331-48.
PMID: 25281883 DOI: 10.1016/j.neuropsychologia.2014.09.034

Many human behaviours and pathologies have been attributed to the putative mirror neuron system, a neural system that is active during both the observation and execution of actions. While there are now a very large number of papers on the mirror neuron system, variations in the methods and analyses employed by researchers mean that the basic characteristics of the mirror response are not clear. This review focuses on three important aspects of the mirror response, as measured by modulations in corticospinal excitability: (1) muscle specificity; (2) direction; and (3) timing of modulation. We focus mainly on electromyographic (EMG) data gathered following single-pulse transcranial magnetic stimulation (TMS), because this method provides precise information regarding these three aspects of the response. Data from paired-pulse TMS paradigms and peripheral nerve stimulation (PNS) are also considered when we discuss the possible mechanisms underlying the mirror response. In this systematic review of the literature, we examine the findings of 85 TMS and PNS studies of the human mirror response, and consider the limitations and advantages of the different methodological approaches these have adopted in relation to discrepancies between their findings. We conclude by proposing a testable model of how action observation modulates corticospinal excitability in humans. Specifically, we propose that action observation elicits an early, non-specific facilitation of corticospinal excitability (at around 90ms from action onset), followed by a later modulation of activity specific to the muscles involved in the observed action (from around 200ms). Testing this model will greatly advance our understanding of the mirror mechanism and provide a more stable grounding on which to base inferences about its role in human behaviour.

Matched MeSH terms: Muscle, Skeletal/physiology*
Evaluation of repetitive isometric contractions on the heads of triceps brachii muscle during grip force exercise

Ali MA, Sundaraj K, Ahmad RB, Ahamed NU, Islam MA, Sundaraj S

Technol Health Care, 2014;22(4):617-25.
PMID: 24990168 DOI: 10.3233/THC-140833

Normally, surface electromyography electrodes are used to evaluate the activity of superficial muscles during various kinds of voluntary contractions of muscle fiber. The objective of the present study was to investigate the effect of repetitive isometric contractions on the three heads of the triceps brachii muscle during handgrip force exercise.

Matched MeSH terms: Muscle, Skeletal/physiology
Fulltext Vitamin E in sarcopenia: current evidences on its role in prevention and treatment

Khor SC, Abdul Karim N, Ngah WZ, Yusof YA, Makpol S

Oxid Med Cell Longev, 2014;2014:914853.
PMID: 25097722 DOI: 10.1155/2014/914853

Sarcopenia is a geriatric syndrome that is characterized by gradual loss of muscle mass and strength with increasing age. Although the underlying mechanism is still unknown, the contribution of increased oxidative stress in advanced age has been recognized as one of the risk factors of sarcopenia. Thus, eliminating reactive oxygen species (ROS) can be a strategy to combat sarcopenia. In this review, we discuss the potential role of vitamin E in the prevention and treatment of sarcopenia. Vitamin E is a lipid soluble vitamin, with potent antioxidant properties and current evidence suggesting a role in the modulation of signaling pathways. Previous studies have shown its possible beneficial effects on aging and age-related diseases. Although there are evidences suggesting an association between vitamin E and muscle health, they are still inconclusive compared to other more extensively studied chronic diseases such as neurodegenerative diseases and cardiovascular diseases. Therefore, we reviewed the role of vitamin E and its potential protective mechanisms on muscle health based on previous and current in vitro and in vivo studies.

Matched MeSH terms: Muscle, Skeletal/metabolism
Olfactory ensheathing cells seeded muscle-stuffed vein as nerve conduit for peripheral nerve repair: a nerve conduction study

Lokanathan Y, Ng MH, Hasan S, Ali A, Mahmod M, Htwe O, et al.

J Biosci Bioeng, 2014 Aug;118(2):231-4.
PMID: 24598302 DOI: 10.1016/j.jbiosc.2014.02.002

We evaluated bridging of 15 mm nerve gap in rat sciatic nerve injury model with muscle-stuffed vein seeded with olfactory ensheathing cells as a substitute for nerve autograft. Neurophysiological recovery, as assessed by electrophysiological analysis was faster in the constructed biological nerve conduit compared to that of autograft.

Matched MeSH terms: Muscle, Skeletal/pathology
Fulltext Cross-talk in mechanomyographic signals from the forearm muscles during sub-maximal to maximal isometric grip force

Islam MA, Sundaraj K, Ahmad RB, Sundaraj S, Ahamed NU, Ali MA

PLoS One, 2014;9(5):e96628.
PMID: 24802858 DOI: 10.1371/journal.pone.0096628

This study aimed: i) to examine the relationship between the magnitude of cross-talk in mechanomyographic (MMG) signals generated by the extensor digitorum (ED), extensor carpi ulnaris (ECU), and flexor carpi ulnaris (FCU) muscles with the sub-maximal to maximal isometric grip force, and with the anthropometric parameters of the forearm, and ii) to quantify the distribution of the cross-talk in the MMG signal to determine if it appears due to the signal component of intramuscular pressure waves produced by the muscle fibers geometrical changes or due to the limb tremor.

Matched MeSH terms: Muscle, Skeletal/physiology*

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