The relationship between myofiber characteristics and meat quality of Chinese Qinchuan and Luxi cattle

Lu Xiao,Yang Yuying,Zhang Yimin,Mao Yanwei,Liang Rongrong,Zhu Lixian,Luo Xin 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.4

Objective: The objectives of this study were to explore the expression patterns of myosin heavy chain (MyHC) genes of different skeletal muscles from Chinese cattle, and to investigate the relationship between myofiber characteristics and meat quality of M. longissimus lumborum (LL), M. psoas major (PM), and M. semimembranosus (SM) from Chinese Luxi and Qinchuan cattle. Methods: Three major muscles including LL, PM, and SM from Chinese Luxi cattle and Chinese Qinchuan cattle were used in this study. The myofiber characteristics were measured by histochemical analysis. The MyHC isoforms expression was evaluated by real-time quantitative polymerase chain reaction. Quality traits including pH value, meat color, cooking loss, Warner-Bratzler shear force (WBSF) and sarcomere length were determined at day 5 postmortem. Results: PM muscle had higher pH value, a* value, sarcomere length and lower WBSF value compared to LL and SM muscles (p<0.05). Numbers of type I myofiber and the relative expression of MyHC I mRNA in PM muscle were higher than those of LL and SM muscles (p<0.05). Myofiber diameter of PM muscle was lower than that of LL and SM muscles, regardless of myofiber types (p<0.05). Conclusion: According to the stepwise linear regression analyses, tenderness was influenced by myofiber characteristics in all three examined muscles. Tenderness of beef muscles from Qinchuan and Luxi cattle could be improved by increasing numbers of type I myofiber. Objective: The objectives of this study were to explore the expression patterns of myosin heavy chain (<i>MyHC</i>) genes of different skeletal muscles from Chinese cattle, and to investigate the relationship between myofiber characteristics and meat quality of <i>M. longissimus lumborum</i> (LL), <i>M. psoas major</i> (PM), and <i>M. semimembranosus</i> (SM) from Chinese Luxi and Qinchuan cattle.Methods: Three major muscles including LL, PM, and SM from Chinese Luxi cattle and Chinese Qinchuan cattle were used in this study. The myofiber characteristics were measured by histochemical analysis. The MyHC isoforms expression was evaluated by real-time quantitative polymerase chain reaction. Quality traits including pH value, meat color, cooking loss, Warner-Bratzler shear force (WBSF) and sarcomere length were determined at day 5 postmortem.Results: PM muscle had higher pH value, <i>a</i>* value, sarcomere length and lower WBSF value compared to LL and SM muscles (p<0.05). Numbers of type I myofiber and the relative expression of <i>MyHC I</i> mRNA in PM muscle were higher than those of LL and SM muscles (p<0.05). Myofiber diameter of PM muscle was lower than that of LL and SM muscles, regardless of myofiber types (p<0.05).Conclusion: According to the stepwise linear regression analyses, tenderness was influenced by myofiber characteristics in all three examined muscles. Tenderness of beef muscles from Qinchuan and Luxi cattle could be improved by increasing numbers of type I myofiber.

Effects of Seated Exercise of Thoracic and Abdominal Muscles on Upper Extremity Function and Trunk Muscles Activity in Patients with Chronic Stroke

Shinjun Park,Sangduk Kim 국제물리치료연구학회 2020 Journal of International Academy of Physical Ther Vol.11 No.2

Background: Weakness of the abdominal and mid thoracic muscles the lead to thoracic kyphosis of stroke patients. The trunk muscles activity of stroke patients is significantly related to upper extremity. Objectives: To investigate the effect of seated exercise of thoracic and abdominal muscles on upper extremity function and trunk muscles activity in stroke patients. Design: One-group pretest-posttest design. Methods: A total of 27 stroke patients were recruited. All stroke patient were given seated abdominal exercise (posterior pelvic tilt exercises) and thoracic exercise (postural-correction exercise). All exercises were conducted for 30 minutes, three times a week for four weeks. The manual function test (MFT) and electromyography (EMG) were measured, and EMG electrodes were attached to thoracic paraspinal muscles and lower rectus abdominal muscles. EMG signal is expressed as %RVC (reference voluntary contraction). Results: Experimental group showed significant increases in abdominal muscles, paraspinal muscles activity and MFT total score, items of arm motion (forward elevation of the upper extremity, lateral elevation of the upper extremity, touch the occiput with the palm) in MFT after four weeks. Conclusion: These results suggest that, in stroke patients, seated exercise of thoracic and abdominal muscles contribute to improve trunk muscles activity and upper extremity function in stroke patients.

Sternocleidomastoid and Posterior Cervical Muscle Coordination in Response to Symmetrical and Asymmetrical Jaw Functions in Normal Adults

Im, Yeong-Gwan,Kim, Jae-Hyung,Kim, Byung-Gook Korean Academy of Orofacial Pain and Oral Medicine 2015 Journal of Oral Medicine and Pain Vol.40 No.3

Purpose: The aim of this study was to elucidate the coordination patterns of the sternocleidomastoid and posterior cervical muscles in response to symmetrical and asymmetrical jaw functions in normal adults. Methods: Twenty-seven healthy volunteers (8 females, 19 males; mean age, $30.4{\pm}2.5$ years) participated in this study. Surface electromyography (EMG) was used to record activities in the masseter, suprahyoid, sternocleidomastoid, and posterior cervical muscles at rest and during maximum tooth clenching, biting of a cotton roll with the anterior teeth, unilateral biting of a cotton roll with the posterior teeth, bilateral biting of cotton rolls with the posterior teeth, and jaw opening while seated. Normalized amplitude, activity indices, and asymmetry indices were compared between the muscles and the jaw tasks. Results: During symmetrical jaw functions (e.g., tooth clenching, biting with the anterior teeth, bilateral biting with the posterior teeth, jaw opening), the sternocleidomastoid and posterior cervical muscles showed elevated EMG amplitudes compared with the resting condition. The co-activation pattern of the sternocleidomastoid muscle was more pronounced than those of the posterior cervical muscles during these tasks. During asymmetrical jaw functions (e.g., unilateral biting with the posterior teeth), the ipsilateral sternocleidomastoid and masseter muscles showed higher contraction activity than did the contralateral muscles, but the contralateral posterior cervical muscles were more active than the ipsilateral muscles. Conclusions: The sternocleidomastoid and posterior cervical muscles were shown to be co-activated and coordinated anteroposteriorly or bilaterally according to symmetrical or asymmetrical jaw function. These results suggest an integrated neural control mechanism for the jaw and neck muscles, and provide further evidence supporting the intimate functional coupling between the trigeminal and cervical neuromuscular systems.

정상인에서 경두개 자기 자극을 이용한 삼킴근의 운동신경유발전위 특성

박성희,송광섭,서정환 대한재활의학회 2009 Annals of Rehabilitation Medicine Vol.33 No.2

Objective: To evaluate the characteristics of the motor evoked potentials (MEPs) and the cortical topography of swallowing muscles in healthy subjects. Method: Fourteen healthy subjects were enrolled. Their mean age was 31 years. Transcranial magnetic stimulation was applied to left and right motor cortices in turn and contralateral electromyographic recordings were done from orbicularis oris, masseter, submental and infrahyoid muscles during resting. The scalp sites of maximal response and the lowest stimulus output which elicited motor evoked potential (MEP) of these muscles were recorded. The onset latency and peak-to-peak amplitude of MEP were measured for each muscle. Results: Most of the maximal MEPs of swallowing muscles were evoked within 9∼17 cm lateral and 1∼5 cm anterior from Cz and they showed interhemispheric symmetry. In submental and infrahyoid muscles, the threshold of right cortical excitability was significantly lower than that of left cortical excitability. The latency of the left submental MEP was statistically shorter than that of right submental MEP. Conclusion: These results demonstrated that the cortical representation of swallowing muscles displays interhemispheric symmetry. In addition, we suggest that submental and infrahyoid muscles have right cortical dominant tendency. Objective: To evaluate the characteristics of the motor evoked potentials (MEPs) and the cortical topography of swallowing muscles in healthy subjects. Method: Fourteen healthy subjects were enrolled. Their mean age was 31 years. Transcranial magnetic stimulation was applied to left and right motor cortices in turn and contralateral electromyographic recordings were done from orbicularis oris, masseter, submental and infrahyoid muscles during resting. The scalp sites of maximal response and the lowest stimulus output which elicited motor evoked potential (MEP) of these muscles were recorded. The onset latency and peak-to-peak amplitude of MEP were measured for each muscle. Results: Most of the maximal MEPs of swallowing muscles were evoked within 9∼17 cm lateral and 1∼5 cm anterior from Cz and they showed interhemispheric symmetry. In submental and infrahyoid muscles, the threshold of right cortical excitability was significantly lower than that of left cortical excitability. The latency of the left submental MEP was statistically shorter than that of right submental MEP. Conclusion: These results demonstrated that the cortical representation of swallowing muscles displays interhemispheric symmetry. In addition, we suggest that submental and infrahyoid muscles have right cortical dominant tendency.

코어운동 Bolster의 적용자세와 움직임에 따른 체간 심부근과 운동근의 근전도 반응

이병근,김기홍,정동춘 대한운동학회 2014 아시아 운동학 학술지 Vol.16 No.2

[INTRODUCTION] The purposes of this study were to measure EMG responses of trunk deep stabilizing and mobilizing muscles by several posture and movement using unstable Bolster, and to analyze the effects of the unstable exercise instrument. [METHOD] The subjects were 15 college men. The subjects were participated supine 6 posture and movements, sitting 5 posture and movements for 20 seconds each by random order. EMG responses were measured by RMS(root mean square) on trunk deep stabilizing muscles(transversus abdominis & obliques abdominis internus, and gluteus medius), and mobilizing muscles(rectus abdominis, and rectus femoris) with surface electrode. RVS(reference voluntary contraction) were measured and analysed after standardization. Oneway ANOVA and post hoc were applied. [RESULTS] As the results of comparison about EMG responses on unstable Bolster posture and movements, there were significant difference on RMS of 4 muscles(p<0.01). RMS of supine unstable Bolster posture and Bolster movements were higher than that of non-Bolster posture on almost of muscles. On comparison among 5 sitting unstable Bolster posture and movements, there were significant difference on 3 muscles(p<0.05, p<0.01). RMS of sitting unstable Bolster tiny movements were some higher than that of non-Bolster posture on 3 muscles. [CONCLUSION] On all of 4 muscles on supine positions, and 3 muscles on sitting positions, there were significants difference on RMS of postures and movements. On supine conditions, RMS of trunk deep stabilizing muscles were relatively higher than those of mobilizing muscles on tiny movement rather than supine non-Bolster posture, but those of rectus abdominis were very higher on Bolster rolling buttocks. In case of tiny movements and exercise movements using unstable Bolster, RMS of trunk deep stabilizing and mobilizing muscles were increased about 10~40%. The future researches may include that the effects of variety posture and movements of upper and lower body to trunk deep stabilizing and mobilizing muscles, and the effects for muscloskeletal disease. [서론] 본 연구의 목적은 와위와 좌위의 자세에서 코어운동 도구인 불안정 Bolster를 적용하거나 이용하여 움직임을 수행하는 동안 체간 심부근과 운동근의 근전도 반응을 측정하여 불안정 운동 도구의 효과는 분석하는 데 있다. [방법] 본 연구에서는 남자 대학 생 15명(23.0±2.5yrs, 176.4±5.4cm, 73.1±11.0kg)을 연구대상으로 하여, 와위 평지 1가지, on-Bolster 5가지, 좌위 평지 1가지, on-Bolster 4가지 조건에 대해 각각 20초씩 무선할당하여 근전도를 측정하였다. 체간 심부근은 복횡근-내복사근과 중둔근을, 운동근은 복직근과 대퇴직근을 대상으로 표면전극을 이용하여 근활성도를 RMS로 측정하였다(LXM3208-RF, LAXTHA, Korea). 기준 수축(RVC)을 측정하고 표준화하여 분석하였다. 일원변량분석(Oneway ANOVA)을 실시하였고 post hoc을 실시하였다. [결과] 와위에서 6가지 자세 및 움직임에 대한 근전도를 비교한 결과, 4가지 근육의 RMS는 동작간 유의한 차이가 나타났다(p<0.01). 대부분의 근육에서 와위 non-Bolster stable보다 on-Bolster stable과 on-Bolster tiny rocking에서 RMS가 높게 나타났다. 좌위 5가지 자세를 비교한 결과, 복횡근-내복사근, 중둔근 및 대퇴직근에서 유의한 차이가 나타났다(p<0.05, p<0.01). non-Bolster stable보다 tiny rocking과 rolling에서의 RMS가 다소 높게 나타났다. [결론] 와위에서는 4가지 근육 모두에서, 좌위에서는 3가지 근육에서 자세와 동작 간에 RMS에 유의한 차이가 나타났다. 와위에서는 4가지 supine non-Bolster posture보다 tiny movement에서 체간 심부근은 운동근보다 상대적으로 근활성도가 더 증가하나, 운동근 중 복직근은 Bolster rolling buttocks에서 현저한 근활성도 증가가 나타났다. Bolster를 이용하여 좌위에서 미동이나 운동 동작을 수행하는 경우, 체간 심부근과 운동근의 RMS가 약 10~40% 정도 증가하였다. 향후 연구에서는 남녀 모두와 다양한 연령층을 대상으로 하여 상체와 하체의 여러 가지 자세와 동작이 다양한 체간 심부근과 운동군 등에 미치는 영향, 근관절 질환자 등을 위한 효과 등으로 적용할 수 있겠다.

다발근염/피부근염의 자기공명영상 소견

이학수 대한영상의학회 1998 대한영상의학회지 Vol.39 No.1

Purpose: The purpose of this study was to evaluate the MR findings and useful sequences in Polymyositis/Dermatomyositis, and to correlate MR findings with disease activity. Materials and Methods: The study included nine clinically proven cases of Polymyositis/Dermatomyositis, eight involving the thigh and one, the shoulder (2 cases, 1 follow-up). The contrast between affected and normal muscles and difference in signal intensity ratio in the muscle groups were retrospectively evaluated on Gd-enhanced T1WI and T2WI. We also evaluated the magnitude of involvement of muscle groups, fatty replacement of muscle and change of subcutaneous fat layer, and correlated signal intensity ratio with serum level of muscle enzymes. Differences in signal intensity ratio and the frequency of chemical shift artifact were evaluated on T2WI as active and inactive groups classified according to clinical findings, and the chemical shift artifact was correlated with the finding of Gd-enhanced T1WI. Exvept in the case of one shoulder, statistical analysis was assessed by the Anova test and t-test. Results: On Gd-enhanced T1WI and T2WI contrast was 0.54 and 0.82, respectively and p value was 0.02. With regard to difference in signal intensity ratios of muscle groups, as seen on Gd-enhanced T1WI and T2WI, p valves were 0.07 and < 0.01, respectively. Muscle involvement was thus clearly visualized on T2WI. The order of frequency of involved muscle groups was vastus muscles, gluteus maximus, sartorius muscles, adductor muscles, gracilis muscle, and hamstring muscles. Fatty replacement and subcutaneous fatty change were visualized in five cases and one, respectively. The correlation coefficient between the signal intensity seen on T2WI and muscle enzymes was 0.59 (CPK) and 0.52 (LDH). The chemical-shift artifact was detected in both clinical groups (four active two inactive) and corresponded to one case of muscle involvement and five of perimuscular edema, as seen on Gd-enhanced T1WI. Conclusion: T2WI is useful for the evaluation of muscle involvement and correlated closely with disease activity; signal intensity ratio could not be substituted for the serum level of muscle enzymes. The group of thigh muscles most affected was the vastus muscles, while the hamstring muscles were least affected. The chemical-shift artifact corresponded mainly to perimuscular edema and did not correlate with disease activity.

Fetal development of deep back muscles in the human thoracic region with a focus on transversospinalis muscles and the medial branch of the spinal nerve posterior ramus

Sato, Tatsuo,Koizumi, Masahiro,Kim, Ji Hyun,Kim, Jeong Hyun,Wang, Bao Jian,Murakami, Gen,Cho, Baik Hwan Blackwell Publishing Ltd 2011 Journal of anatomy Vol.219 No.6

<P><B>Abstract</B></P><P>Fetal development of human deep back muscles has not yet been fully described, possibly because of the difficulty in identifying muscle bundle directions in horizontal sections. Here, we prepared near‐frontal sections along the thoracic back skin (eight fetuses) as well as horizontal sections (six fetuses) from 14 mid‐term fetuses at 9–15 weeks of gestation. In the deep side of the trapezius and rhomboideus muscles, the CD34‐positive thoracolumbar fascia was evident even at 9 weeks. Desmin‐reactivity was strong and homogeneous in the superficial muscle fibers in contrast to the spotty expression in the deep fibers. Thus, in back muscles, formation of the myotendinous junction may start from the superficial muscles and advance to the deep muscles. The fact that developing intramuscular tendons were desmin‐negative suggested little possibility of a secondary change from the muscle fibers to tendons. We found no prospective spinalis muscle or its tendinous connections with other muscles. Instead, abundant CD68‐positive macrophages along the spinous process at 15 weeks suggested a change in muscle attachment, an event that may result in a later formation of the spinalis muscle. S100‐positive intramuscular nerves exhibited downward courses from the multifidus longus muscle in the original segment to the rotatores brevis muscles in the inferiorly adjacent level. The medial cutaneous nerve had already reached the thoracolumbar fascia at 9 weeks, but by 15 weeks the nerve could not penetrate the trapezius muscle. Finally, we propose a folded myotomal model of the primitive transversospinalis muscle that seems to explain a fact that the roofing tile‐like configuration of nerve twigs in the semispinalis muscle is reversed in the multifidus and rotatores muscles.</P>

Electrochemical graphene/carbon nanotube yarn artificial muscles

Hyeon, Jae Sang,Park, Jong Woo,Baughman, Ray H.,Kim, Seon Jeong Elsevier 2019 Sensors and actuators. B, Chemical Vol.286 No.-

<P><B>Abstract</B></P> <P>Fiber-type artificial muscles similar to natural muscles are being studied for applications such as robots, prosthetics and exoskeletons. In particular, carbon nanotube (CNT) yarn artificial muscles have attracted interest for their unique mechanical and electrical properties as electrochemical artificial muscles. Here, we demonstrate the large tensile stroke of CNT-based electrochemical yarn artificial muscles induced by increasing capacitance. The coiled graphene/CNT yarns made by the biscrolling method can produce greater tensile actuation using more ions at the same voltage than pristine CNT coils. The maximum tensile actuation of these electrochemical muscles is 19%, which is two times larger than coiled CNT muscles with a work capacity of 2.6 J g<SUP>−1</SUP>. These electrochemical artificial muscles could be further developed for practical applications, such as micromechanical devices and robotics.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Coiled graphene/CNT yarns were prepared for electrochemical artificial muscles. </LI> <LI> More ions were induced in the CNT yarns by grahpene at the same voltage. </LI> <LI> The graphene/CNT muscles contracted twice more than pristine CNT muscles through capacitance increase. </LI> </UL> </P>

구개열 환자에서 전자현미경을 이용한 구순 근육의 미토콘드리아성 근병증에 관한 연구

김석화 大韓成形外科學會 1993 Archives of Plastic Surgery Vol.20 No.6

Schendel, et al(1989) have already shown the mitochondrial myopathy of the lip muscles in the cleft lip by the histochemical study. And the mitochondrial myopathy of the soft palate muscles in the cleft palate was reported by Kim, et al(1990). It has been suggested that the mitochondria1 myopathy of the muscles at the edge of the cleft be one of the factors evoking the cleft during the embryogenesis. As the control of the soft palate muscles in 11 cleft palate patients, the lip muscles are obtained for the electron microscopic study. The lip muscles in the cleft, palate show the increase in the number of the mitochondria and the variation of the size of the mitochondria, which are indicative of the mitochondrial myopathy. And mitochondrial myopathy is severer in the palatal muscles at the cleft margin than in the lip muscles. This study demonstrates that the lip muscles, which do not, have cleft, in the cleft palate are not normal. This suggests that some of the morphologic deformities of the facial muscles associated with the cleft palate may cause the soft tissues to inhibit the subsequent bone growth activity.

Sternocleidomastoid and Posterior Cervical Muscle Coordination in Response to Symmetrical and Asymmetrical Jaw Functions in Normal Adults

임영관,김재형,김병국 대한안면통증∙구강내과학회 2015 Journal of Oral Medicine and Pain Vol.40 No.3

Purpose: The aim of this study was to elucidate the coordination patterns of the sternocleidomastoidand posterior cervical muscles in response to symmetrical and asymmetrical jaw functionsin normal adults. Methods: Twenty-seven healthy volunteers (8 females, 19 males; mean age, 30.4±2.5 years)participated in this study. Surface electromyography (EMG) was used to record activities in themasseter, suprahyoid, sternocleidomastoid, and posterior cervical muscles at rest and duringmaximum tooth clenching, biting of a cotton roll with the anterior teeth, unilateral biting of acotton roll with the posterior teeth, bilateral biting of cotton rolls with the posterior teeth, andjaw opening while seated. Normalized amplitude, activity indices, and asymmetry indices werecompared between the muscles and the jaw tasks. Results: During symmetrical jaw functions (e.g., tooth clenching, biting with the anterior teeth,bilateral biting with the posterior teeth, jaw opening), the sternocleidomastoid and posteriorcervical muscles showed elevated EMG amplitudes compared with the resting condition. Theco-activation pattern of the sternocleidomastoid muscle was more pronounced than those ofthe posterior cervical muscles during these tasks. During asymmetrical jaw functions (e.g., unilateralbiting with the posterior teeth), the ipsilateral sternocleidomastoid and masseter musclesshowed higher contraction activity than did the contralateral muscles, but the contralateralposterior cervical muscles were more active than the ipsilateral muscles. Conclusions: The sternocleidomastoid and posterior cervical muscles were shown to be co-activatedand coordinated anteroposteriorly or bilaterally according to symmetrical or asymmetricaljaw function. These results suggest an integrated neural control mechanism for the jawand neck muscles, and provide further evidence supporting the intimate functional couplingbetween the trigeminal and cervical neuromuscular systems.