• International Journal of Contents
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• 제5권4호
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• pp.35-39
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• 2009

The purpose of this study was to evaluate the changes in skeletal muscle architecture and qualitative properties by muscle contraction force when neuromuscular electrical stimulation (NMES) of 50% MVIC was applied. Sixteen subjects (8 male, 8 female) without neuromuscular disease volunteered to participate in the study. All subjects were divided into two subgroups: control (no electrical stimulation) group and 50% maximal voluntary isometric contraction (MVIC) group. NMES training program was performed in the calf muscle three times a week for 10 weeks. Before and after the experiments, the MVIC of ankle plantar flexor was measured by the use of dynamometer, and the ultrasonography in the gastrocnemius medialis muscle was measured. The following results were obtained; MVIC was significantly increased in the electrical stimulation groups. Pennation angle, muscle density, and white area index also considerably changed in the electrical stimulation groups. In conclusion, the NMES training of 50% MVIC, comparative low level, improved the skeletal muscle architecture and the qualitative properties as well as the muscle contraction force.

• 대한치과교정학회지
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• 제15권2호
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• pp.249-259
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• 1985

To analyze the skeletal characteristics of the open bite, the faces of normal occlusion and open bite were measured using a cephalogram. The factors which were greatly different from normal occlusion were selected. The effects of these factors on the incisal overbite and correlation on these factors were studied. The following results were obtained: 1. The 13 factors which comprised the characteristics of the open bite were obtained. (Table 5) 2. The cause and amount of the open bite were dependent on the skeletal angulation than skeletal length. 3. For determining the incisal overbite, most highly correlated single factor was the interincisal angle. 4. The correlation on the selected 13 factors which comprised the characteristics of the open bite was obtained. (Table 6) 5. The open bite was due to combination of various factors than due to single factor. (Table 3,4).

• The Journal of Korean Physical Therapy
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• 제14권3호
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• pp.373-406
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• 2002

This study was peformed to investigate the effects on skeletal muscle recovery with aqua-exercise; swimming to take the muscle endurance for 20 days on two group of white rats which were the low extremity atrophy group(control groups) by fixed for two weeks and aqua-exercise group(experimental groups) after it. The effects was observed with light and electron microcope to measure the morphological changes of muscle fibers. The results obtained were as follow. 1. Light microscope: In the case of control groups, quadriceps fibers had been irregular alignment, decreased muscle width and the irregular alignment nuclear appeared, as it is degenerative muscle fibers. In the case of experimental groups, the fibers had been regular alignment cells and fibers. The nucleus of muscle had been normal characterized by oval shape and fiber sarcomere clearly classified. 2. Electron microscope: In the case of control groups, there were the quadriceps which was Z-line streaming phenomenon induced at the sarcomere and cells nuclear separated from basal membrane. It was not only observed the sarcomere alignment irregularly and mitochondria damaged, but also vacuoles found. In the case of experimental groups, A band, I band, H band had been clearly appeared, classified at the myofibrils of quadriceps, and electronic dense M-line found in sarcomere. There were observed satellite cells and basal laminas that usually to be appeared at the time of mitochondrial development, skeletal muscle fiber regeneration or development. This results suggest that the aqua-exercise assisted to inhibit the degenerative morphological changes of skeletal muscle cells and help to recover from abnormal states. Especially, it is considered to effect on a normal structural formation.

• 대한예방한의학회지
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• 제12권2호
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• pp.27-35
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• 2008

Purpose : The experiments was undertaken to evaluate the effects of Ojeoksan-herbal medicine, in rats' fetus Methods : Female Sprague-Dawley rats were orally administered with the Ojeoksan at dose of 5mg/kg/day for 20 days. Pregnant rats were sacrificed at 20th day of gestation, and observed internal and reproductive organs. Approximately live fetuses in the 20th day of gestation were randomly selected and fixed in 95% ethanol. Results : Neonatal body weight and number of fetus of Ojeoksan group were increased to that of control group. The fetuses of dams treated with Ojeoksan didn't showed external malformation. Vertebral and sternal skeletal variations were observed in Ojeoksan administered group, but compared to the control, those skeletal variations were insignificant. There were no significant changes in number of ribs, cervical, thoracic, lumber, sacral and caudal Conclusion : From these results, it can be concluded that Ojeoksan showed no toxicity effects on number of live fetuses. There were no significant changes in skeletal variations were showed in vertebrate and sternum, Ojeoksan weren't shown significant changes in bone malformation. We need more precise study to investigate the mechanism of early or late resorption by the herbal medicines such as Ojeoksan.

• Molecules and Cells
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• 제28권3호
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• pp.189-194
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• 2009

The modulating effect of IGF-I on the regulation of AR gene expression and activation in skeletal muscle cells remains poorly understood. In this study, the effects of IGF-I treatment on AR induction and activation in the absence of AR ligands were examined. Differentiating C2C12 cells were treated with different concentrations (0-250 ng/ml) of IGF-I or for various periods of time (0-60 min) of 250 ng/ml IGF-I. Treatment of C2C12 cells with IGF-I resulted in a dose- and time-dependent increase in total AR and phosphorylated AR (Ser 213). IGF-I treatment also led to significantly increased AR mRNA expression when compared with the control. The levels of skeletal ${\alpha}-actin$ and myogenin mRNA, known target genes of AR, were also significantly upregulated after 5 or 10 min of treatment with IGF-I. Confocal images revealed that IGF-I stimulated nuclear localization of AR in the absence of ligands. In addition, an electrophoretic mobility shift assay indicated that IGF-I stimulated the AR DNA binding activity in a time-dependent manner. The present results suggest that IGF-I stimulates the expression and activation of AR by ligand-independent mechanism in differentiating C2C12 mouse skeletal muscle cells.

• Journal of mucopolysaccharidosis and rare diseases
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• 제2권1호
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• pp.8-12
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• 2016

Mucolipidosis (ML) is a kind of skeletal dysplasia. Characteristic X-ray findings of the bone may contribute to the early diagnosis and treatment of ML II/III. Skeletal radiographs show distinctive patterns at different ages: neonatal hyperparathyroidism, osteodystrophy (similar to chronic osteitis fibrosa cystica), and dysostosis multiplex. Patients with ML II/III show a mixture of osteodystrophic bone changes and atypical changes of dysostosis multiplex: proximal pointing of the metacarpals in the wrist, dysplastic changes in the lower third of the ilia, marked broadening of the ribs becoming oar-shaped, and beaking of the lower thoracic and lumbar vertebrae. In ML II, the osteodystrophy has clinical and radiographic features of neonatal hyperparathyroidism. In some neonatal subjects, chemical hyperparathyroidism is also demonstrated. After transient hyperparathyroidism in newborns, the progressive osteitis fibrosa cystica develops from 3-6 months of age. Patients with ML III show prominent skeletal involvement, particularly the destruction of vertebral bodies and the femoral heads. Intravenous pamidronate treatment is well tolerated, and it can produce clinical effects, with a reduction in bone pain and improvements in mobility in patients with ML III. In this review, the skeletal manifestations of ML II and III are investigated.

• Osteoporosis and Sarcopenia
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• 제2권3호
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• pp.140-155
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• 2016

Sex steroids influence the maintenance and growth of muscles. Decline in androgens, estrogens and progesterone by aging leads to the loss of muscular function and mass, sarcopenia. These steroid hormones can interact with different signaling pathways through their receptors. To date, sex steroid hormone receptors and their exact roles are not completely defined in skeletal and smooth muscles. Although numerous studies focused on the effects of sex steroid hormones on different types of cells, still many unexplained molecular mechanisms in both skeletal and smooth muscle cells remain to be investigated. In this paper, many different molecular mechanisms that are activated or inhibited by sex steroids and those that influence the growth, proliferation, and differentiation of skeletal and smooth muscle cells are reviewed. Also, the similarities of cellular and molecular pathways of androgens, estrogens and progesterone in both skeletal and smooth muscle cells are highlighted. The reviewed signaling pathways and participating molecules can be targeted in the future development of novel therapeutics.

• 한국잠사곤충학회지
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• 제51권2호
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• pp.123-129
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• 2013

The purpose of this study is to investigate the effects of supplementation of mulberry powder, mulberry extract and silkworm powder during the 8 weeks of resistance exercise on muscle increase of rats. Fifty males, Sprague-Dawley rat, were randomly divided into 5 groups: CON(control group, n = 10), REG(resistance exercise group, n = 10), MP REG(mulberry powder intake and resistance exercise group, n = 10), ME REG(mulberry extract intake and resistance exercise group, n = 10) and SP REG(silkworm powder intake and resistance exercise group, n = 10). After climbing the ladder without weights during the 1 week of adaptation period, the rats in the resistance exercise group were trained to climb a 0.98-m vertical(80 degree incline) ladder with weights in their tail during 7 weeks(10 times each day, 2 days per week). After exercise, the skeletal muscle was extracted from the flexor hallucis longus. The absolute weight of skeletal muscle was measured by the electronic balance and the relative weight of skeletal muscle about the weight was calculated. The strength and density of legs muscle were analyzed by the computed tomography scan. After 8 weeks of resistance exercise, the absolute weight of skeletal muscle wasn't significant, but it increased in MP REG 8%, ME REG 8% and SP REG 10% compared to REG. The relative weight of skeletal muscle increased significantly in SP REG compared to REG (p < 0.05). Additionally, there was a significant increase of density and strength of the forelegs in SP REG compared to CON (p < 0.05). However, there was no significant increase of density and strength of the hind legs. In conclusion, regular resistance exercise made rats muscle increase and there was more muscle increase effected by providing silkworm.

• 한국직업건강간호학회지
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• 제29권4호
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• pp.342-353
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• 2020

Purpose: This study aimed to systematically review literature and conduct a meta-analysis to comprehensively identify and evaluate the effects of workplace risk assessment-based ergonomic intervention on work-related muscular-skeletal disorders in workers. Methods: We searched the Ovid-Medline, EMBASE, and Cochrane library and up to 2018 using search terms such as muscular-skeletal, disorder, impairment, work-related muscular-skeletal disorders, ergonomic, intervention, management with no language limitations; screened reference lists; and contacted experts in the field. Results: We identified 545 references and included 13 randomized controlled tests (3,368 workers). We judged nine studies to have a low risk of bias, while the other four studies have a high risk of bias. Conclusion: Ergonomic intervention based on risk assessment in the workplace did not significantly differ in terms of the intensity of pain or duration of workers in the workplace, but low-quality evidence decreased the frequency of musculoskeletal disorder pain in three to six months moderate-quality evidence and in six to nine months low-quality evidence. Besides, low-quality evidence to reduce discomfort and moderate-quality evidence to improve worker posture. Therefore, ergonomic intervention based on the assessment of risk factors in the workplace should be applied to reduce pain frequency and discomfort and improve workers posture among musculoskeletal disorders.

• 대한예방한의학회지
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• 제12권3호
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• pp.35-45
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• 2008

Purpose : To evaluate safety of Sibjeondaebotang and Yugmijihwangtang in rats' fetus Methods : Female Sprague-Dawley rats were orally administered with the Sibjeondaebotang and Yugmijihwangtang at dose of 5mg/kg/day for 20 days. Pregnant rats were sacrificed at 20th day of gestation. Approximately live fetuses in the 20th day of gestation were randomly selected and fixed in 95% ethanol. To observe skeletal malformations, fetuses were stained with alcian blue and alizarin red S. Results : Neonatal body weight and number of fetus of Sibjeondaebotang, Yugmijihwangtang group were increased to those of control group. The fetuses treated with Sibjeondaebotang, Yugmijihwangtang didn't showed external malformation. Vertebral and sternal skeletal variations were observed in Sibjeondaebotang, Yugmijihwangtang administered group, but compared to the control, those skeletal variations were insignificant. There were no significant changes in number of ribs, cervical, thoracic, lumbar, sacral and caudal vertebrae Conclusion : From these results, it can be concluded that Sibjeondaebotang, Yugmijihwangtang shows no toxicity effects on fetus body weight and number of live fetuses. Although skeletal variations were shown in vertebrate and sternum, Sibjeondaebotang, Yugmijihwangtang did not show significant changes in bone malformation.