• Title/Summary/Keyword: MUSCLE ACTIVATION

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Anti-Proliferative Activity of OD78 Is Mediated through Cell Cycle Progression by Upregulation p27kip1 in Rat Aortic Vascular Smooth Muscle Cells

  • Tudev, Munkhtsetseg;Lim, Yong;Park, Eun-Seok;Kim, Won-Sik;Lim, Il-Ho;Kwak, Jae-Hwan;Jung, Jae-Kyung;Hong, Jin-Tae;Yoo, Hwan-Soo;Lee, Mi-Yea;Pyo, Myoung-Yun;Yun, Yeo-Pyo
    • Biomolecules & Therapeutics
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    • v.19 no.2
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    • pp.187-194
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    • 2011
  • Atherosclerosis and post-angiography restenosis are associated with intimal thickening and concomitant vascular smooth muscle cell (VSMC) proliferation. Obovatol, a major biphenolic component isolated from the Magnolia obovata leaf, is known to have anti-inflammatory and anti-tumor activities. The goal of the present study was to enhance the inhibitory effects of obovatol to improve its potential as a preventive or therapeutic agent in atherosclerosis and restenosis. Platelet-derived growth factor (PDGF)-BB-induced proliferation of rat aortic smooth muscle cells (RASMCs) was examined in the presence or absence of a newly synthesized obovatol derivative, OD78. The observed anti-proliferative effect of OD78 was further investigated by cell counting and [$^3H$]-thymidine incorporation assays. Treatment with 1-4 ${\mu}M$ OD78 dose-dependently inhibited the proliferation and DNA synthesis of 25 ng/ml PDGF-BB-stimulated RASMCs. Accordingly, OD78 blocked PDGF-BB-induced progression from the $G_0/G_1$ to S phase of the cell cycle in synchronized cells. OD78 decreased the expression levels of CDK4, cyclin E, and cyclin D1 proteins, as well as the phosphorylation of retinoblastoma protein and proliferating cell nuclear antigen; however, it did not change the CDK2 expression level. In addition, OD78 inhibited downregulation of the cyclin-dependent kinase inhibitor (CKI) $p27^{kip1}$. However, OD78 did not affect the CKI $p21^{cip1}$ or phosphorylation of early PDGF signaling pathway. These results suggest that OD78 may inhibit PDGF-BB-induced RASMC proliferation by perturbing cell cycle progression, potentially through $p27^{kip1}$ pathway activation. Consequently, OD78 may be developed as a potential anti-proliferative agent for the treatment of atherosclerosis and angioplasty restenosis.

The Effect of NO Donor on Contraction, Cytosolic $Ca^{2+}$ Level and Ionic Currents in Guinea-pig Ileal Smooth Muscle

  • Kwon, Seong-Chun;Park, Ki-Young;Ahn, Duck-Sun;Lee, Young-Ho;Kang, Bok-Soon
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.1
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    • pp.33-40
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    • 2000
  • This study was designed to clarify the mechanism of the inhibitory action of a nitric oxide (NO) donor, 3-morpholino-sydnonimine (SIN-1), on contraction, cytosolic $Ca^{2+}$ level $([Ca^{2+}]_i)$ and ionic currents in guinea-pig ileum. SIN-1 $(0.01{\sim}100\;{\mu}M)$ inhibited 25 mM KCl- or histamine $(10\;{\mu}M)-induced$ contraction in a concentration-dependent manner. SIN-1 reduced both the 25 mM KCl- and the histamine-stimulated increases in muscle tension in parallel with decreased $[Ca^{2+}]_i.$ Using the patch clamp technique with a holding potential of -60 mV, SIN-1 $(10\;{\mu}M)$ decreased peak Ba currents $(I_{Ba})$ by $30.9{\pm}5.4%$ (n=6) when voltage was stepped from -60 mV to +10 mV and this effect was blocked by ODQ $(1\;{\mu}M),$ a soluble guanylyl cyclase inhibitor. Cu/Zn SOD (100 U/ml), the free radical scavenger, had little effect on basal $I_{Ba},$ and SIN-1 $(10\;{\mu}M)$ inhibited peak $I_{Ba}$ by $32.4{\pm}5.8%$ (n=5) in the presence of Cu/Zn SOD. In a cell clamped at a holding-potential of -40 mV, application of $10\;{\mu}M$ histamine induced an inward current. The histamine-induced inward current was markedly and reversibly inhibited by $10\;{\mu}M$ SIN-1, and this effect was abolished by ODQ $(1\;{\mu}M).$ In addition, SIN-1 markedly increased the depolarization-activated outward $K^+$ currents in the all potential ranges. We concluded that SIN-1 inhibits smooth muscle contraction mainly by decreasing $[Ca^{2+}]_i$ resulted from the inhibition of L-type $Ca^{2+}$ channels and the inhibition of nonselective cation currents and/or by the activation of $K^+$ currents via a cGMP-dependent pathway.

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Ultrastructural and Immunohistochemical Study of Hepatic Fibrosis after the Ligation of the Common Bile Duct in Rats (백서의 총담관 결찰에 의한 간 섬유화의 초미세구조적 및 면역조직화학적 연구)

  • Moon, Kyung-Rye;Rho, Young-Ill;Seo, Woo-Chul;Park, Yeong-Bong;Kim, Man-Woo;Seo, Jae-Hong;Park, Sang-Kee
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.2 no.2
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    • pp.185-193
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    • 1999
  • Purpose: Proliferation of bile duct-like structures and fibrosis is a hepatic cellular reaction observed in most forms of human liver disease and in a variety of experimental conditions associated with liver injury. The aim of this study was to investigate the activation of Ito cells and bile duct proliferation in the rat after common bile duct ligation (CBDL). Methods: Hepatic morphological abnormalities were examined in rats whose bile ducts had been irreversibly ligated for 15, 21, 24 and 28 days. The liver was examined by immunohistochemical staining for ${\alpha}$-smooth muscle actin, the known marker of activated Ito cells, and light and electron microscopes. Results: After CBDL, the bile canalicular proliferation and interstitial fibrosis were gradually increased in the periportal areas extended to hepatic sinusoids. Ito cells positive for ${\alpha}$-smooth muscle actin were frequently observed in the periductular space and in perisinusoidal space of Disse. Ito cells and myofibroblasts were gradually increased in the interstitial fibrosis until the 28th day after CBDL. Ito cells and myofibroblasts had microfilaments with dense body at the periphery of the cell. Conclusions: Our results suggest that Ito cells may be fibroblastic or myogenic. It has also been postulated that during the development of hepatic fibrosis, Ito cells become myofibroblasts or fibroblast like cells.

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Effect on the Activity and Ratio of the Serratus Anterior, Pectoralis Major, and Upper Trapezius according to the Angle of Abduction and External Weight During Shoulder Protraction Exercise for Winged Scapular Subjects (날개 어깨뼈 대상자들에게 어깨 내밈 운동시 벌림 각도와 외부 무게에 따른 앞톱니근, 큰가슴근, 위 등세모근의 활성도 및 비율에 미치는 영향)

  • BadamKhorl, Yadam;Kim, Tae-ho;Park, Han-kyu
    • Physical Therapy Korea
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    • v.26 no.3
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    • pp.1-10
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    • 2019
  • Background: Winged scapular (WS) causes muscle imbalance with abnormal patterns when moving the arm. In particular, the over-activation of the upper trapezius (UT) and decrease in activity of the lower trapezius (LT) and serratus anterior (SA) produce abnormal scapulohumeral rhythm. Therefore, the SA requires special attention in all shoulder rehabilitation programs. In fact, many previous studies have been devoted to the SA muscle strength training needed for WS correction. Objects: The purpose of this study was to investigate the effect of shoulder girdle muscle and ratio according to the angle of shoulder abduction and external weight in supine position. Methods: Twenty three WS patients participated in this experiment. They performed scapular protraction exercise in supine position with the weights of 0 kg, 1 kg, 1.5 kg, and 2 kg at shoulder abduction angles of $0^{\circ}$, $30^{\circ}$, $60^{\circ}$, and $90^{\circ}$. The angle and weight applications were randomized. Surface electromyography (EMG) was used to collect the EMG data of the SA, pectoralis major (PM), and UT during the exercise. The ratio of PM/SA and UT/SA was confirmed. Two-way repeated analyses of variance were used to determine the statistical significance of SA, PM, and UT and the ratios of PM/SA and UT/SA. Results: There was a significant difference in SA according to angle (p<.05). Significant differences were also identified depending on the angle and weight (p<.05). The angle of abduction at $0^{\circ}$, $30^{\circ}$ and weight of 2 kg showed the highest SA activity. However, there was no significant difference between PM and UT (p>.05). There was a significant difference between PM/SA and UT/SA in ratio of muscle activity according to angle (p<.05). Significant differences were found at PM/SA angles of $30^{\circ}$, $60^{\circ}$ and $90^{\circ}$ (p<.05). For UT/SA, significant difference was only observed at $90^{\circ}$ (p<.05). Conclusion: Based on the results of this study, in order to strengthen the SA, it was found to be most effective to use 1 and 1.5 kg weights with abduction angles of $0^{\circ}$ and $30^{\circ}$ at shoulder protraction in supine position.

The Effect of Abdominal Drawing-in Maneuver Aapplied to Sitting Position in Healthy Adult on Grip Power (정상 성인에서 앉은 자세에 적용한 복부 드로우인 기법이 파악력에 미치는 영향)

  • Kim, Chang-Sook
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.3
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    • pp.475-482
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    • 2020
  • The abdominal drawing-in maneuver(ADIM), which is performed to strengthen the stabilization muscles of the lumbar, is an exercise method that selectively contracts the TrA and IO by increasing intra-abdominal pressure. In order to check the effect of ADIM in sitting position, which is the most frequently used posture in everyday life, on how to grip power, ADIM was conducted in a sitting position for 30 healthy adults, and then the state was not performed. In each, the grip power was measured to determine how ADIM performed in the sitting position had an effect on grip power and which muscles had the most influence. The muscles mobilized for the electromyography(EMG) measurement were RA, EO, IO/TrA, and ES, which were the most activation lumbar stabilization muscles when ADIM was applied. As a result of the study, the activity on muscles of the lumbar stabilization was significantly increased and the grip power of the muscles was significantly increased than the ADIM in the sitting position. By comparing the measured difference value of each muscle, it was found that any muscle had a greater effect on grip power, but no muscle showed a significant correlation. It is thought that the increase of intra-abdominal pressure did not affect the grip power of a specific muscle. Therefore, if ADIM is performed in a sitting position that is frequently used in everyday life through this study, it will be more effective in increasing the grip power and lumbar stabilization.

Effects of Visual Feedback Treadmill Gait Training Program Combined with Virtual Reality Technology and a Force Plate Measurement System on Gait Ability and Quality of Life in Stroke Patients (가상현실과 힘판을 통한 시각적 되먹임 트레드밀 보행훈련이 뇌졸중 환자의 보행능력과 삶의 질에 미치는 영향)

  • Lee, Dong-Ryul
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.3
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    • pp.363-373
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    • 2020
  • The purpose of this study was to improve the gait ability and quality of life of stroke patients by combining virtual reality technology and a visual feedback gait training program with entertainment elements. Ten stroke patients with circumduction gait were selected. The visual feedback treadmill gait training program using virtual reality technology and a force plate measurement system was conducted 30 minutes a day, 5 days a week, with 25 sessions in 5 weeks. To investigate the effects of this gait training program, evaluations using the joint range-of-motion test, muscle activity tests, Berg balance scale (BBS), gait analysis, and stroke-specific quality-of-life scale (SS-QOL) were performed before and after intervention. Statistically significant differences were found in the joint range of motion and muscle activity of the affected side from the initial swing phase to the mid-swing phase of the gait cycle, dynamic balance, gait function, and quality of life (p <0.05). The results of this study indicate that the gait training program improved the foot drop, muscle activity, dynamic balance, and gait ability of stroke patients with circumduction gait, thereby improving the quality of life of the patients. Therefore, we recommend the application of the visual feedback treadmill gait training program using virtual reality technology and a force plate measurement system to improve gait ability and quality of life of stroke patients with circumduction gait.

Effects of Dynamic Tubing Gait Training on Postural Alignment, Gait, and Quality of Life in Chronic Patients with Parkinson's Disease : Case Study (동적탄력튜빙 보행훈련 프로그램이 만성 파킨슨병 환자의 자세정렬과 보행능력과 삶의 질에 미치는 영향 : 사례연구)

  • Lee, Dong-Ryul
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.8
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    • pp.363-377
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    • 2021
  • The present study investigated the effects of dynamic tubing gait training(I and II) on the postural alignment, gait, and quality of life in chronic patients with Parkinson's disease. This study is based on the case study that recruited a total of 3 patients with chronic Parkinson's disease (Hoehn and Yahr Stage of 1 to 3 each one person). Dynamic tubing gait training (I and II) applied to chronic patients with Parkinson's disease for 25 sessions, 30 minutes a day, 5 days a week, over 5 weeks period. To investigate the effects of this study, evaluating using the postural alignment test, muscle activity tests, gait analysis, and quality of life scale for patient with Parkinson's disease. After the intervention of Dynamic tubing gait training (I and II), Trunk flexion was decreased. Also, during walking from initial contact (IC) to mid stance (Mst), muscle activity of Quadriceps, Hamstring, and Tibialis Anterior (TA) was increased and muscle activity of Gastrocnemius was decreased. The muscle activation of Erector Spinae (ES T12, L3) was increased in the H&Y I and III stages and decreased in the H&Y II stage. Length of gait line, single support line, ant/post position and lateral symmetry of center of pressure (COP) parameters improved. The spatio-temporal gait parameters including of step length, stride length, and velocity was increased, and cadence decreased. Further the quality of life of patients with Parkinson's disease was improved. Based on these findings, Dynamic tubing gait training (I and II) could be applied as a new approach to improve posture, gait, quality of life in chronic patients with Parkinson's disease for more than 5 years, whose drug resistance is halved.

Assessment of Effect of Pulmonary Rehabilitation on Skeletal Muscle Metabolism by $^{31}P$ Magnetic Resonance Spectroscopy (호흡재활치료 전후 $^{31}P$ 자기공명분석법을 이용한 골격근대사의 변화에 관한 연구)

  • Cho, Won-Kyung;Kim, Dong-Soon;Choe, Kang-Hyeon;Park, Young-Joo;Lim, Tae-Hwan;Shim, Tae-Sun;Lim, Chae-Man;Lee, Sang-Do;Koh, Youn-Suck;Kim, Woo-Sung;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1040-1050
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    • 1997
  • Pulmonary rehabilitation has been known to improve dyspnea and exercise tolerance in patients with chronic lung disease, although it does not improve pulmonary function. The mechanism of this improvement is not clearly explained till now; however some authors suggested that the improvement in the skeletal muscle metabolism after the rehabilitation could be a possible mechanism. The metabolc changes in skeletal muscle in patients with COPD are characterized by impaired oxidative phosphorylation which causes early activation of anaerobic glycolysis and excess lactate production with exercise. In order to evaluate the change in the skeletal muscle metabolism as a possible cause of the improvement in the exercise tolerance after the rehabilitation, noninvasive $^{31}P$ magnetic resonance spectroscopy(MRS) of the forearm flexor muscle was performed before and after the exercise training in nine patients with chronic lung disease who have undertaken intensive pulmonary rehabilitation for 6 weeks. 31p MRS was studied during the sustained isometric contraction of the dominant forearm flexor muscles up to the exhaustion state and the recovery period. Maximal voluntary contraction(MVC) force of the muscle was measured before the isometric exercise, and then 30% of MVC force was constantly loaded to each patient during the isometric exercise. After the exercise training, exercise endurance of upper and lower extremities and 6 minute walking distance were significantly increased(p<0.05). There were no differences of baseline intracellular pH (pHi) and inorganic phosphate/phosphocreatine(Pi/PCr). After rehabilitation pHi at the exercise and the exhaustion state showed a significant increase($6.91{\pm}0.1$ to $6.99{\pm}0.1$ and $6.76{\pm}0.2$ to $6.84{\pm}0.2$ respectively, p<0.05). Pi/PCr at the exercise and the recovery rate of pHi and Pi/PCr did not show significant differences. These results suggest that the delayed intracellular acidosis of skeletal muscle may contribute to the improvement of exercise endurance after pulmonary rehabilitation.

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Electroencephalogram(EEG) Activation Changes and Correlations of signal with EMG Output by left and right biceps (좌우 이두근의 근전도 출력에 따른 뇌파의 활성도 변화와 관련성 탐색)

  • Jeon, BuIl;Kim, Jongwon
    • Journal of IKEEE
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    • v.23 no.2
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    • pp.727-734
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    • 2019
  • This paper confirms whether the movement or specific operation of the muscles in the process of transferring a person from the brain can find a signal showing an essential feature of a certain part of the brain. As a rule, the occurrence of EEG(Electroencephalogram) changes when a signal is received from a specific action or from an induced action. These signals are very vague and difficult to distinguish from the naked eye. Therefore, it is necessary to define a signal for analysis before classification. The EEG form can be divided into the alpha, beta, delta, theta and gamma regions in the frequency ranges. The specific size of these signals does not reflect the exact behavior or intention, since the band or energy difference of the activated frequencies varies depending on the EEG measurement domain. However, if different actions are performed in a specific method, it is possible to classify the movement based on EEG activity and to determine the EEG tendency affecting the movement. Therefore, in this article, we first study the EEG expression pattern based on the activation of the left and right biceps EMG, and then we determine whether there is a significant difference between the EEG due to the activation of the left and right muscles through EEG. If we can find the EEG classification criteria in accordance with the EMG activation, it can help to understand the form of the transmitted signal in the process of transmitting signals from the brain to each muscle. In addition, we can use a lot of unknown EEG information through more complex types of brain signal generation in the future.

Effects of long-term tubular HIF-2α overexpression on progressive renal fibrosis in a chronic kidney disease model

  • Dal-Ah Kim;Mi-Ran Lee;Hyung Jung Oh;Myong Kim;Kyoung Hye Kong
    • BMB Reports
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    • v.56 no.3
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    • pp.196-201
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    • 2023
  • Renal fibrosis is the final manifestation of chronic kidney disease (CKD) regardless of etiology. Hypoxia-inducible factor-2 alpha (HIF-2α) is an important regulator of chronic hypoxia, and the late-stage renal tubular HIF-2α activation exerts protective effects against renal fibrosis. However, its specific role in progressive renal fibrosis remains unclear. Here, we investigated the effects of the long-term tubular activation of HIF-2α on renal function and fibrosis, using in vivo and in vitro models of renal fibrosis. Progressive renal fibrosis was induced in renal tubular epithelial cells (TECs) of tetracycline-controlled HIF-2α transgenic (Tg) mice and wild-type (WT) controls through a 6-week adenine diet. Tg mice were maintained on doxycycline (DOX) for the diet period to induce Tg HIF-2α expression. Primary TECs isolated from Tg mice were treated with DOX (5 ㎍/ml), transforming growth factor-β1 (TGF-β1) (10 ng/ml), and a combination of both for 24, 48, and 72 hr. Blood was collected to analyze creatinine (Cr) and blood urea nitrogen (BUN) levels. Pathological changes in the kidney tissues were observed using hematoxylin and eosin, Masson's trichrome, and Sirius Red staining. Meanwhile, the expression of fibronectin, E-cadherin and α-smooth muscle actin (α-SMA) and the phosphorylation of p38 mitogen-activated protein kinase (MAPK) was observed using western blotting. Our data showed that serum Cr and BUN levels were significantly lower in Tg mice than in WT mice following the adenine diet. Moreover, the protein levels of fibronectin and E-cadherin and the phosphorylation of p38 MAPK were markedly reduced in the kidneys of adenine-fed Tg mice. These results were accompanied by attenuated fibrosis in Tg mice following adenine administration. Consistent with these findings, HIF-2α overexpression significantly decreased the expression of fibronectin in TECs, whereas an increase in α-SMA protein levels was observed after TGF-β1 stimulation for 72 hr. Taken together, these results indicate that long-term HIF-2α activation in CKD may inhibit the progression of renal fibrosis and improve renal function, suggesting that long-term renal HIF-2α activation may be used as a novel therapeutic strategy for the treatment of CKD.