• The Korean Journal of Zoology
• /
• v.24 no.4
• /
• pp.173-188
• /
• 1981

근세포의 분화에 있어서의 근특이 단백질의 합성 순서를 구명하기 위하여 계배 근세포를 2$\\sim$9일간 배양하면서 단백질합성야상을 SDS-polyacrylamide 겔전기 영동법, 등전점초점2차원 전기영동법 및 방사자기법으로 분석하였다. Actin은 분화의 초기부터 활발히 합성되어 그 양이 다량으로 축적되나, myosin은 배양 3일째부터 대량 합성되기 시작하였다. Myosin의 대량합성시기는 배양 근원세포가 융합을 활발히 일으키는 시기와 거의 같았다. Myoglobin은 분화초기부터 서서히 합성축적되기 시작하여 배양 5일에서 최대치에 달하였다. Creatine phosphokinase는 배양 3일만에, 그리고 glyceraldehyde dehydrogenase는 6일만에 전기영동상에 검출되었다. Tropomyosin $\\alpha$와 $\\beta$, 그리고 troponin C는 분화초기부터 비교적 다량 합성되고 있었다. 젖산탈수소효소의 활성은 배양 2$\\sim$5일 사이에서 급격히 증가하고 이후 거의 변화가 없었다. 이 효소의 동위효소 조성은 초기 근원세포에서는 $H_4$와 $H_3M$형이 많으나 분화가 진행됨에 따라 $HM_3 와 M_4$형이 서서히 출현하였다. 그리고 배양 5일만에 5종의 동위효소가 모두 검출되었다.

• The Korean Journal of Zoology
• /
• v.24 no.4
• /
• pp.189-200
• /
• 1981

Drastic alterations in myogenesis could be induced by ultraviolet irradiation of the myogenic cells derived from 12 day old chick embryo skeletal muscle. The effects of irradiation on various aspects, including cell division, transformation to myotubes, and morphology of myoblasts and myotubes, were examined. Irradiated cells were smaller in size, and only few cells transformed resulting in smaller size of myotubes with a narrow width. Both the inhibiting actions to cell division and to fusion were more striking when irradiated at earlier stages after plating. As well, cell division and fusion were inhibited more effectively with increasing UV dose and excessive amount caused cell death. A lowering cell density was thought to account for the decrease in myogenesis and possible reasons for the decrease in the capacity for fusion were discussed in view of the results presented in this report and of the findings from other laboratories.

• International Journal of Advanced Culture Technology
• /
• v.7 no.1
• /
• pp.209-215
• /
• 2019

In order to provide a safe free-weight-training environment to people without workout trainers, we suggest a smart bench press machine with an automatic weight control system sensitive to user tiredness. Physical weight plates on the machine are replaced with a hydraulic cylinder as a press load and the cylinder knob is coupled with a step motor to change its tensile force automatically in-between lifting exercises. Three subjects participated to verify the usability of the smart bench press machine. They were asked to lift a 6-RM press load 10 times with 3 different lifting conditions: 1) no assistance, 2) a human assistance, and 3) the automatic weight control. All subjects were not able to complete the 10 sets without assistance due to tiredness, but they finished the full sets under the two assistive conditions. Average lifting speeds under the automatic weight control condition showed the most consistent level. Normalized quasi-tension data based on surface electromyogram signals of both Pectoralis Majors revealed that the subjects maintained the target muscle activation level above 50% but not more than 80% throughout the 10 sets. Therefore, the smart bench press machine is expected to both keep pace with the lifting exercise and reduce risk of injuries due to excessive muscle tensions.

• Physical Therapy Rehabilitation Science
• /
• v.11 no.2
• /
• pp.145-153
• /
• 2022

Objective: The purpose of this study was to evaluate the Electromyography (EMG) of the upper limb during reaching tasks according to two heights in the sitting position. Design: Cross sectional design Methods: Fifteen hemiplegia, fifteen elderly, and fifteen healthy subjects have participated in this study. The targets (90% length of the subject's arm) were located at the two heights (the eye and xiphoid process). We have recorded EMG signals of seven upper limb muscles (anterior deltoid (AD), posterior deltoid (PD), pectoralis major (Pec), infraspinatus (Inf), supraspinatus (Sup), biceps brachii (Bi), triceps brachii (Tri)). The dependent variables were movement time(s), modulation ratio, working ratio, and the co-contraction ratio of the hemiplegia, elderly, and healthy at the reaching task. Two-way repeated-measures ANOVA (2-heights) was analyzed with the LSD post hoc test. Results: The study results were as follows: (1) The movement time to the target during reaching movement was significantly longer for the hemiplegia and elderly groups compared to the healthy group. (2) The modulation rate was significantly higher at eye height than the xiphoid height in AD, PD, Pec, Inf, Bi muscles, and the hemiplegia group and elderly group were significantly lower than the healthy group. Additionally, the modulation ratio showed a significant interaction between heights and groups. Conclusions: It is expected that the variables using the muscle contraction characteristics, the evaluation method of this study, can be used as an electromyography-based feedback method that can be objectively evaluated and quantified in clinical practice.

• Physical Therapy Korea
• /
• v.7 no.2
• /
• pp.88-95
• /
• 2000

Thirty normal adults were tested to measure the electrical activity of the anterior (AD), middle (MD), and posterior portion (PD) of the deltoid muscle and sternal portion of the pectoralis major muscle (PM) during the performance of four upper extremity PNF diagonal patterns with elbow flexion angle in $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$. The PNF patterns in which these muscles function optimally have been theoretically advanced by Kabat and further described by Knott and Voss. They theorize that the MD should be most active with shoulder flexion, abduction, and external rotation (D2F); the PD with shoulder extension, abduction, and internal rotation (D1E); the AD with shoulder flexion, adduction, and external rotation (D1F); and the PM with shoulder extension, adduction and internal rotation (D2E). The patterns were performed through range of motion, with an isometric contraction performed in the shortened range. When the EMG activity of AD, MD, PD and PM in its optimal patterns was measured, it does not have significant difference among fixed elbow flexion angle $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$ (p>.05). In addition, suggestions were made for study of patients who exhibit imbalance of muscle strength and have muscle weakness.

• Food Science of Animal Resources
• /
• v.38 no.5
• /
• pp.835-850
• /
• 2018

The dramatic improvements in the growth rate and breast muscle size and yield in broilers through the intensive genetic selection, and the improvement in nutrition and management over the past 50 years have introduced serious abnormalities that influenced the quality of breast meat. The abnormalities include pale-soft-exudative (PSE) conditions, deep pectoral muscle (DPM) myopathy, spaghetti meat (SM), white striping (WS), and woody breast (WB) that have serious negative implications to the broiler meat industry. The incidences of PSE and DPM have been known for several decades, and their prevalence, etiology and economic impact have been well discussed. However, other abnormalities such as SM, WS and WB conditions have been reported just for few years although these conditions have been known for some time. The newly emerging quality issues in broilers are mainly associated with the Pectoralis major muscles, and the incidences have been increased dramatically in some regions of the world in recent years. As high as 90% of the broilers are affected by the abnormalities, which are expected to cause from $200 million to $1 billion economic losses to the U.S. poultry industry per year. So, this review mainly discusses the histopathological characteristics and biochemical changes in the breast muscles with the emphasis on the newly emerging abnormalities (SM, WS, and WB) although other abnormalities are also discussed. The impacts of the anomalies on the nutritional, functional, mechanical and sensory quality of the meat and their implications to the poultry industry are discussed.

• Journal of the Korean Society of Physical Medicine
• /
• v.10 no.2
• /
• pp.55-61
• /
• 2015

PURPOSE: The purpose of this study was to investigate recruiting order and onset time around shoulder muscle during the push-up according to the body tilting angle. METHODS: Twenty healthy young adult subjects were recruited for this study. They had no neurological and musculoskeletal disease. We used the sEMG for recording onset time of shoulder muscles. Shoulder Muscles were anterior deltoid(AD), posterior deltoid(PD), pectoralis major(PM), upper trapezius(UT). Body tilting angle were measured at 0 degree, 30 degree and 60 degree by using tilting table. Muscles contraction onset time were set by the push-up performed 3 times respectively. Mean of 3 measurements were used. And initiate onset time was decided by the Mean ${\pm}2$ SD in the threshold, more than 25ms. RESULTS: There were significant difference at 0 degree, 30 degree and 60 degree(p<.05). Muscles onset time were same order at 0 degree, 30 degree. UT occurred first of all contraction at 0 degree and 30 degree. And then contracted AD, PD, PM. But, at 60 degree, AD was the first contraction, and PM, UT, PD. CONCLUSION: Muscle recruitment order and onset time according to the body tilting was shown the difference when you do push-up. Therefore, this result, shoulder muscle recruitment pattern of according to the body tilting is different and it has to make effective shoulder exercise program.

• Journal of the Korea Convergence Society
• /
• v.9 no.2
• /
• pp.341-347
• /
• 2018

The purpose of this study is to examine the change to the muscle activity from the serratus anterior(SA) of 5th and 7th, upper trapezius(UT), middle trapezius(MT) lower trapezius (LT), and pectoralis major(PM) when push-up plus exercise(PUP) is performed in four postures. 25 healthy, young participants performed various PUP convergence exercise(general posture, $90^{\circ}$, $120^{\circ}$ and BOSU). The muscle activity of the shoulder stability muscles was measured using a surface EMG analysis system during various PUP convergence exercise. One-way repeated-measure of ANOVA was conducted to comparison the activity of each muscle. There was significant difference in SA7, PM, UT, and MT (p <.05) during various PUP. The muscle activity of SA7 had a significance difference between PUP and $90^{\circ}PUP$ or BOSUPUP respectively (p <.05). The muscle activity of PM had a significance difference between $90^{\circ}PUP$ and PUP or BOSUPUP (p <.05). The muscle activity of UT had a significance differnce between $90^{\circ}PUP$ and PUP or BOSUPUP (p <.05). The muscle activity of MT had a significance differnce between $90^{\circ}PUP$ and PUP and also significantly difference PUP and $120^{\circ}PUP$(p <.05). These results suggest that general PUP can be a useful to improve to scapular stabilizer muscle in who has no shoulder dysfunction.

• Archives of Plastic Surgery
• /
• v.34 no.3
• /
• pp.346-351
• /
• 2007

Purpose: As a rare congenital anomaly, Poland's syndrome has been known to show hypoplasia in breast and nipple, absence of pectoralis major muscle, and aplasia or deformity of rib or costal cartilage which has been reported to be more common in male. However, most patients who are seeking operation are female patients having one-side deformity. In the field of plastic surgery, the major surgical indications could be asymmetric chest wall depression in man or breast hypoplasia in woman. There are many reconstruction options according to the degree of patient's deformity: a prosthetic implant, breast implant with or without tissue expander, latissimus dorsi musculocutaneous pedicled flap with or without implant and/or tissue expander, and free tissue transfer with or without tissue expander. Methods: The authors have treated 4 patients(2 male, 2 female) who had a diagnosis of Poland's syndrome. According to the degree of patient's deformity, all patients underwent correction of breast asymmetry and unilateral anterior thoracic hypoplasia with one-staged or two-staged reconstruction. Results: All patents were satisfied with the results and there occurred no specific complications. Conclusion: The authors propose the treatment plan for patient with Poland's syndrome, according to the degree of patient's deformity. In case of male patient with mild deformity, the prosthetic implant or latissimus dorsi musculocutaneous pedicled flap will simulate the missing pectoralis and improve the contour deformity. In case of female patient with moderate to severe breast asymmetry and upward displaced nipple areolar complex (NAC), NAC can be lowered with tissue expander, breast can be enlarged with autologous free flaps or latissimus dorsi musculocutaneous pedicled flap with implant.

• Journal of Chest Surgery
• /
• v.17 no.1
• /
• pp.125-128
• /
• 1984

The management of the exposed cardiac pacemaker or its lead is a new challenge to the plastic surgeon. This complication is not rare. Coburn et al. [1972] reported less than 5 percent, but Sowton et al. [1974] showed that over a period of 19 years, in a series of 372 patients, the pacing system had to be removed because of local wound breakdown or infection in 10 percent of the cases. The methods used to treat exposure may vary from removal and re-introduction at anterior site to the rotation of local flaps to cover the exposed pacemaker. Recently we have experienced 6 times of migration and recurrent skin ulcerations without pyogenic infection overlying the pacemaker in one patient. We developed a new technique, anchoring the pacemaker to the clavicle by a wire through the hole of clavicle and by creating a pocket under the pectoralis major muscle. Then we would like to emphasize this operating method could be choice of treatment to prevent the migration of pacemaker and the ulceration of skin when complication of implantation of pacemaker is occurred.