• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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• pp.611-613
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• 1998

A structure of musculotendon model with a fatigue profile is investigated. The Hill-type musculotendon model can predicts the decline in muscle force for a given fatigue profile. It consists of nonlinear activation and contraction dynamics based on the physiological concepts. It is normalized for generalization to deal with the various muscles. Muscle force generated by continuous tetanic electrical monophasic pulsewidth modulation stimulation is decreased in time. A fatigue profile is expressed by a function of intramuscular acidification and applied to the relationship between muscle force and shortening velocity in contraction dynamics. The results of computer simulation are well matched with data in a literature which are isometrically performed for knee extension muscles. Also change in optimal fiber length has an effect only on muscle time, constant not on the steady-state tetanic force.

• 생명과학회지
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• 제21권9호
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• pp.1259-1265
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• 2011

본 연구의 목적은 일회성 유산소 운동이 TLR4, IL-6, TNF-${\alpha}$, SOCS-3 유전자 발현에 미치는 영향을 쥐의 골격근에서 살펴보는데 있었다. 또한 이러한 일회성 운동의 영향이 근섬유 형태 특이적으로 나타나는 지에 대한 연구도 수행되었다. 실험은 Balb/c 수컷 쥐(male: 7주령, 몸무게 $22.78{\pm}0.27g$) 13마리 대상으로 하였으며, 대조군과 운동군으로 무선배정되었다. 운동은 일회성으로 지칠 때까지 트레드밀 운동(경사도 $10^{\circ}$, speed 17 cm/sec 10 min, 33 cm/sec 10 min, 50 cm/sec)을 실시하였으며, 운동 후 24시간이 지난 시점에서 가자미근과 족저근을 적출하였다. 가자미근과 족저근의 TLR4, IL-6, TNF-${\alpha}$, SOCS-3 mRNA 수준 변화는 real-time PCR을 이용하여 측정하였다. 일회성 유산소 트레드밀 운동은 가자미근에서 TLR4 mRNA 발현을 유의하게 증가시켰지만, 족저근의 TLR4 mRNA 발현에는 유의한 영향을 미치지 않았다. 또한 IL-6, TNF-${\alpha}$, SOCS-3 mRNA 발현은 가자미근에서 일회성트레드밀 운동에 의해 유의하게 증가되었다. 하지만 족저근에서 이들 유전자의 mRNA 발현은 일회성 운동에 의해 영향을 받지 않았다. 결론적으로 TLR4, IL-6, TNF-${\alpha}$, SOCS-3와 같은 면역관련 유전자의 발현 수준은 일회성트레드밀 운동에 의해 근섬유 형태 특이적으로 조절됨을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권9호
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• pp.1430-1438
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• 2019

Objective: This experiment was designed to determine the effects of coated cysteamine hydrochloride (CC) on muscle fiber characteristics, amino acid composition and transporters gene expression in the longissimus dorsi muscle (LDM) of finishing pigs. Methods: Two hundred and sixteen Duroc/Landrace/Yorkshire cross-bred male finishing pigs were fed with a corn-soybean basal diet supplemented with 0, 70, and 140 mg/kg cysteamine. Each group contained eight replicates of nine pigs per replicate. After 29 days, one pig was randomly selected from each replicate and slaughtered. Blood and LDM samples were collected and analyzed. Results: The results showed that supplemental dietary CC increased (p<0.05) the muscle fiber density. And CC supplementation also up-regulated (p<0.05) the expression of myosin heavy chain 1 (MyHC1) and MyHC2x mRNA levels, and down-regulated (p<0.05) MyHC2b expression in the LDM. Additionally, supplemental dietary CC reduced (p<0.05) the concentration of total cholesterol in the plasma and enhanced (p<0.05) the concentrations of essential amino acid and total amino acid in the LDM. The relative expression levels of chloramphenicol acetyltransferase 2, $b^{0,+}$ amino acid transporter, and $y^+$-L-type amino acid transporter 1 were upregulated (p<0.05) in the LDM when pigs were fed with the dietary CC of 70 mg/kg. Conclusion: Cysteamine supplementation could increase fiber density and distribution of fiber types. It also improved the deposition of protein in the LDM by up-regulated the expression of amino acid transporters.

• 한국축산식품학회지
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• 제27권4호
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• pp.401-408
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• 2007

본 연구는 한국 재래 오골계의 성장에 따른 조직학적 및 생리학적 특성을 분석하기 위해 수행하였다. 계군들의 체중, 흉근과 가자미근의 무게 측정 및 시료의 채취는 부화 직후 및 3, 5, 15주령에 이루어졌다. 근섬유 특성은 부화 직후에서 15주령까지의 오골계 흉근과 가자미근을 이용하여 분석하였고, DNA, RNA 및 단백질 함량은 왼쪽 흉근에서 측정하였다. 체중의 상대적인 증가율은 부화 직후에서 3주령까지의 기간에 가장 크게 나타났다. 가슴의 무게는 부화 직후에서 3주령까지의 기간에 약 24.46배가 증가했으며, 가슴 중 흉근도 동일한 기간 동안 약 31.14배 증가하였다. 소퇴부 및 가자미근의 무게 역시 부화 직후에서 3주령까지의 시기에 뚜렷한 증가가 나타났다. 모든 근섬유의 단면적은 성장 기간 동안 증가하는데, 15주의 실험 기간 동안 흉근의 근섬유 단면적은 65배 증가($34.06\;{\pm}\;3.08$에서 $2238\;{\pm}\;177\;{\mu}m^2$)하였다. 흉근의 근섬유 단면적은 부화 직후에서 3주령까지의 기간에는 약 18배, 3주령에서 5주령까지의 기간 동안에는 약 1.6배 증가를 보였다. 따라서 흉근의 근섬유 단면적과 무게 역시 3주령 때까지 가장 큰 증가를 보임을 알 수 있다. 핵산 및 단백질의 함량을 분석한 실험에서도 부화 직후에서 3주령 사이에 가장 큰 증가가 나타났는데, 부화부터 3주령까지의 기간 동안 각각 DNA 총량은 13배, RNA 총량은 21배, 단백질 총량은 30배 증가한 것으로 나타났다.

• 대한임상전기생리학회지
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• 제8권1호
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• pp.23-29
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• 2010

Purpose : This study is to offer clinical primary data that examines the change of imaging structure and the quantitative evaluation of muscle activity on myofascial trigger points. This study examines neuromuscular physiological characteristic by comparing the differences in physical findings, pressure pain threshold, imaging, and electrophysiological characteristics in latent and active myofascial trigger points muscle and normal muscle through the following experimental procedures. Methods : The participants for the study were thirty-three adults in their twenties. We divided three groups into normal, latent and active myofascial trigger points groups by physical findings. We analyzed the results of measured pressure pain, threshold for pain, ultrasound imaging perform for structure characteristic of muscle, surface EMG according to type of muscle contraction for function of muscle contraction. Results : Significant differences were indicated in pressure pain threshold (p<0.05). Significant differences were discovered in the ultrasound imaging analysis. There were increases in muscle Echogenicity white area index (p<0.001). There were significant differences that decrease in %MVIC (p<0.05), increase in MDF (p<0.05). Conclusion : From these results, active rnyotascial trigger points muscle showed quality deterioration on ultrasound imaging and decreased function of muscle contraction, increased motor unit action potential of II type fiber, and electrophysiologically. Imaging structure and neuromuscular physiological characteristic can be diagnostic and quantitative analytical techniques for myofascial pain syndrome and a primary factor that reflected in physical therapy intervention.

• 대한정형도수물리치료학회지
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• 제12권1호
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• pp.57-67
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• 2006

Musculoskeletal neck dysfunction syndromes are common in outpatient musculoskeletal pain practice. The underlying musculoskeletal and neurologic causes of pain are variable. In the management of these patients, it is important to accurately identify and treat these pain generators to optimize patient outcome. It is the purpose of this review to discuss three main categories of functional anatomy, the role of superficial/deep muscular system and the scientific evidence for optimal physical therapy intervention for cervical dysfunction. Specifically there is evidence of lowered microcirculation in the upper trapezius muscle, morphological signs of disturbed mitochondrial function which appears to be limited to type I fibers and an increased cross-sectional area of type I muscle fibers despite a lower capillary to fiber area ratio. In acute neck pain syndrome, changes in muscle activity of painful muscles may result from segmental and supraspinal inhibitory effects. Muscle activation is closely related to the control of joint movements and postures and it is difficult to separate the influence of the two components. Both the altered muscle recruitment patterns and altered kinematics appear to be a poor adaptation for pain of the head - neck region, as they are likely to result in increased compressive loading in the cervical spine, affecting muscles, articular structures such as zygapophyseal joints, connective tissues and neural tissues which are all peripheral generators of referred pain. The rectus capitus posterior minor muscle shows that it is one of the most important muscles of the suboccipital region. In this article, i reviewed the anatomy, neurophysiology, function and dysfunction as well as the treatment of cervical dysfunction.

• 한국전문물리치료학회지
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• 제22권2호
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• pp.70-80
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• 2015

The spinal cord is highly complex, consisting of a specialized neural network that comprised both neuronal and non-neuronal cells. Any kind of injury and/or insult to the spinal cord leads to a series of damaging events resulting in motor and/or sensory deficits below the level of injury. As a result, muscle paralysis (or paresis) leading to muscle atrophy or shrinking of the muscle along with changes in muscle fiber type, and contractile properties have been observed. Traditionally, histology had been used as a gold standard to characterize spinal cord injury (SCI)-induced adaptation in spinal cord and skeletal muscle. However, histology measurements is invasive and cannot be used for longitudinal analysis. Therefore, the use of conventional magnetic resonance imaging (MRI) is promoted to be used as an alternative non-invasive method, which allows the repeated measurements over time and secures the safety against radiation by using radiofrequency pulse. Currently, many of pathological changes and adaptations occurring after SCI can be measured by MRI methods, specifically 3-dimensional MRI with the advanced diffusion tensor imaging technique. Both techniques have shown to be sensitive in measuring morphological and structural changes in skeletal muscle and the spinal cord.

• 대한한의학방제학회지
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• 제24권3호
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• pp.153-161
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• 2016

Chronic alcoholic myopathy is one of the most common skeletal muscle disorders. It is characterized by a reduction in the entire skeletal musculature, skeletal muscle weakness, and difficulties in gait. Patients with alcoholic hepatitis and cirrhosis have severe muscle loss that contributes to worsening outcome. Although the myopathy selectively affects Type II (fast twitch, glycolytic, anaerobic) skeletal muscle fibers, total skeletal musculature is reduced. The severity of the muscle atrophy is proportional to the duration and amount of alcohol consumed and leads to decreased muscle strength. The mechanisms for the myopathy are generally unknown but it is not due to overt nutritional deficiency, nor due to either neuropathy or severe liver disease. Skeletal muscle mass and protein content are maintained by a balance between protein synthesis and breakdown and in vivo animal models studies have shown that ethanol inhibits skeletal muscle protein synthesis. Daekumeumja is a traditional Korean medicine that is widely employed to treat various alcohol-induced diseases. Muscle diseases are often related to liver diseases and conditions. The main objective of this study was to assess that Daekumeumja extract could have protective effect against alcoholic myopathy in a Sprague-Dawley rat model. Rats were orally given 25% ethanol (5ml/kg, body weight) for 8 weeks. After 30 minutes, rats were administrated with Daekumeumja extract. Controls were similarly administrated with the vehicle alone. The weights of gastrocnemius, soleus and plantaris muscles were assessed and the morphologic changes of gastrocnemius and plantaris muscles were also assessed by hematoxylin and eosin staining. In results, The muscles from ethanol treated rats displayed a significant reduction in muscle weight and average cross section area compared to Normal group. Daekumeumja extract treated group showed increased muscle weight and muscle fiber compared to the ethanol treated group. It was concluded that Daekumeumja extract showed ameliorating effects on chronic alcohol myopathy in skeletal muscle.

• 한국축산식품학회지
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• 제44권4호
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• pp.758-778
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• 2024

This study assessed previous research aimed at mitigating the adverse effects of freeze-thawing on meat quality. Specifically, it focuses on assessing the physicochemical alterations in meat resulting from freezing, freeze-thawing, or technologies to minimize these alterations. Recent studies have focused on conventional freeze-thaw technology applicable across various livestock species and muscle types. However, recent research has indicated the necessity for developing freeze-thaw technology considering the unique characteristics of individual muscles. In this review, we summarize previous studies that have compared alterations in the physicochemical properties of primary muscles owing to freezing or freeze-thawing. Despite the introduction of various technologies to significantly reduce the adverse effects on meat quality resulting from freeze-thawing, it is essential to consider the unique characteristics (proximate composition, pH, and muscle fiber characteristics) of individual muscles or cuts to develop enhanced the freeze-thaw processing technology.

• Journal of Ginseng Research
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• 제43권3호
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• pp.475-481
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• 2019

Background: The ginsenoside Rg1 has been shown to exert various pharmacological activities with health benefits. Previously, we have reported that Rg1 promoted myogenic differentiation and myotube growth in C2C12 myoblasts. In this study, the in vivo effect of Rg1 on fiber-type composition and oxidative metabolism in skeletal muscle was examined. Methods: To examine the effect of Rg1 on skeletal muscle, 3-month-old mice were treated with Rg1 for 5 weeks. To assess muscle strength, grip strength tests were performed, and the lower hind limb muscles were harvested, followed by various detailed analysis, such as histological staining, immunoblotting, immunostaining, and real-time quantitative reverse transcription polymerase chain reaction. In addition, to verify the in vivo data, primary myoblasts isolated from mice were treated with Rg1, and the Rg1 effect on myotube growth was examined by immunoblotting and immunostaining analysis. Results: Rg1 treatment increased the expression of myosin heavy chain isoforms characteristic for both oxidative and glycolytic muscle fibers; increased myofiber sizes were accompanied by enhanced muscle strength. Rg1 treatment also enhanced oxidative muscle metabolism with elevated oxidative phosphorylation proteins. Furthermore, Rg1-treated muscles exhibited increased levels of anabolic S6 kinase signaling. Conclusion: Rg1 improves muscle functionality via enhancing muscle gene expression and oxidative muscle metabolism in mice.