• The Korean Journal of Physiology
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• 제30권2호
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• pp.231-236
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• 1996

In our previous study (Kim et al, 1991), GLUT 4 protein content correlated negatively with plasma glucose levels in skeletal muscles of STZ-induced diabetic rats. Thus, in this study, to confirm whether expression of GLUT 4 correlate negatively with degree of hyperglycemia, we measured levels of GLUT 4 mRNA in red and white gastrocnemius muscles in STZ-induced mild and severe diabetic rats. Rats were randomly assigned to control, mild, and severe diabetic groups, and the diabetes was induced by intraperitoneal administration of STZ. The experiment was carried out 10 days after STZ administration. Gastrocnemius red and white muscles were used fur the measurement of GLUT 4 expression. Plasma glucose levels of mild and severe diabetic rats were increased compared to control rats (control, mild, and severe diabetes; $6.4{\pm}0.32,\;9.4{\pm}0.68,\;and\;22.0{\pm}0.58$ mmol/L, respectively). Plasma insulin levels of mild and severe diabetic rats were decreased compared to control rats (control, mild, and severe diabetes; $198{\pm}37,\;l14{\pm}14,\;and\;90{\pm}15$ pmol/L, respectively). GLUT 4 mRNA levels of gastrocnemius red muscles in mild and severe diabetic rats were decreased compared to control rats ($64{\pm}1.2%\;and\;71{\pm}2.0%$ of control, respectively), but GLUT 4 mRNA levels in gastrocnemius white muscles were unaltered in diabetic rats. In summary, GLUT 4 mRNA levels were decreased in STZ-induced diabetic rats but did not correlated negatively with degree of hyperglycemia, and this result suggest that the regulatory mechanisms of decreased GLUT 4 mRNA levels are hypoinsulinemia and/or other metabolic factor but not hyperglycemia. And regulation of GLUT 4 expression in STZ-induced diabetes between red and white enriched skeletal muscles may be related to a fiber specific gene regulatory mechanism.

• 대한핵의학회지
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• 제34권5호
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• pp.433-435
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• 2000

A 6000-year-old male with carcinoma of the prostate and cerebral infarction underwent a Tc-99m MDP bone scintigraphy for the evaluation of skeletal metastases. Bone scintigraphy (Fig. 1) showed multiple areas of increased uptake of Tc-99m MDP in the skull, spine, and ribs representing skeletal metastases. Two different patterns of uptake occurred in the skull region (Fig. 1A-C); one represents bony metastasis and the ether represents cerebral infarction. The shape, size, location, intensity, and border of the increased uptake differed between the two lesions. An oval-shaped pattern with smaller size, greater intensity and more sharply defined border in the frontal region was consistent with bony metastasis. A rectangular-shaped pattern with larger size, lesser intensity and relatively indistinct border in the temporo-parieto-occipital region was consistent with cerebral infarction. Increased uptake of bone-seeking radiotracers in cerebral infarction has been reported previously.$^{1-4)}$ A suggested mechanism by which bone-seeking radiotracers accumulate in the necrotizing cerebral tissue is an alteration of the blood-brain barrier induced during cerebral infarction, which results in entry of the radiotracers into the extracellular space of the brain.$^{4)}$ Brain CT (Fig. 2) performed 7 days before and one month after the bone scintigraphy revealed lesions on the right temporo-parieto-occipital region consistent with acute hemorrhagic and chronic cerebral infarction, respectively.

• Animal Bioscience
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• 제36권12호
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• pp.1775-1784
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• 2023

Objective: The aim of this study was to reveal the role and regulatory mechanism of miR-188-5p in the proliferation and differentiation of goat muscle satellite cells. Methods: Goat skeletal muscle satellite cells isolated in the pre-laboratory were used as the test material. First, the expression of miR-188-5p in goat muscle tissues at different developmental stages was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). In addition, miR-188-5p was transfected into goat skeletal muscle satellite cells by constructing mimics and inhibitors of miR-188-5p, respectively. The changes of differentiation marker gene expression were detected by qPCR method. Results: It was highly expressed in adult goat latissimus dorsi and leg muscles, goat fetal skeletal muscle, and at the differentiation stage of muscle satellite cells. Overexpression and interference of miR-188-5p showed that miR-188-5p inhibited the proliferation and promoted the differentiation of goat muscle satellite cells. Target gene prediction and dual luciferase assays showed that miR-188-5p could target the 3'untranslated region of the calcium/calmodulin dependent protein kinase II beta (CAMK2B) gene and inhibit luciferase activity. Further functional studies revealed that CAMK2B promoted the proliferation and inhibited the differentiation of goat muscle satellite cells, whereas si-CAMK2B restored the function of miR-188-5p inhibitor. Conclusion: These results suggest that miR-188-5p inhibits the proliferation and promotes the differentiation of goat muscle satellite cells by targeting CAMK2B. This study will provide a theoretical reference for future studies on the molecular mechanisms of skeletal muscle development in goats.

• 한국군사과학기술학회지
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• 제26권4호
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• pp.313-323
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• 2023

The wearable robot system is designed to assist human skeletal and muscular systems for enhancing user's abilities in various fields, including medical, industrial, and military. The military has an expanding need for wearable robots with the integration of surveillance/control systems and advanced equipment in unstructured battlefield environments. However, there is a lack of research on the design and mechanism of wearable robots, especially for power assist systems. This study proposes a lightweight wearable robot system that provides comfortable wear and muscle support effects in various movements for soldiers performing high-strength and endurance missions. The Power assist mechanism is described and verified, and the tasks that require power assist are analyzed. This study explain the system including its driving mechanism, control system, and mechanical design. Finally, the performance of the robot is verified through experiments and evaluations, demonstrating its effectiveness in muscle support.

• The Korean Journal of Physiology and Pharmacology
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• 제5권2호
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• pp.183-188
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• 2001

To elucidate antidiabetic effect and mechanism(s) of acarbose in a polygenic spontaneous hyperglycemic and hyperinsulinemic diabetic animal model, $KKA^y$ mice, acarbose was administered orally for 4 weeks and effects on body weight, plasma glucose and insulin levels, genetic expressions of intestinal sucrase-isomaltase (SI), sodium-glucose cotransporter (sGLT1) and glucose transporter in quadriceps muscle (GLUT4) were examined in this study. Although no differences in body weight were detected between control and acarbose-treated groups, plasma glucose level in acarbose-treated group was markedly reduced as compared to the control. In the mechanism study, acarbose downregulated the SI and SGLT1 gene expressions, and upregulated the GLUT4 mRNA and protein expressions when compared to the control group. In conclusion, the data obtained strongly implicate that acarbose can prevent the hyperglycemia in $KKA^y$ mice possibly through blocking intestinal glucose absorption by downregulations of SI and sGLT1 mRNA expressions, and upregulation of skeletal muscle GLUT4 mRNA and protein expressions.

• 대한의생명과학회지
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• 제28권2호
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• pp.59-66
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• 2022

The Cyr61/CTGF/NOV (CCN) family is dynamically expressed in various tissues, including the nervous system, from the prenatal period to adulthood. However, major studies have been conducted only in limited fields, such as the cardiovascular and muscular systems, skeletal development, and cancer. In addition, although the CCN family is a secretory protein, very few studies have described its mechanism of secretion. Recently, it has been suggested that overexpression of CCN3 or intracellular accumulation due to problems in the secretory pathway can inhibit neuronal axonal growth. In this review, we have briefly summarized the structure and characteristics of the CCN family and its related diseases, with particular emphasis on the secretory mechanism and modifiers of the CCN family, newly identified in the nervous system.

• Clinical and Experimental Pediatrics
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• 제49권10호
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• pp.1116-1119
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• 2006

화농근육염은 골격근의 원발성 세균 감염으로, 주로 대퇴사두근이나 둔근에 발생한다. 화농근육염의 병리기전은 잘 알려져 있지 않으나 국소부위의 외상과 동반된 균혈증에 의한 것으로 설명되며, Staphylococcus aureus가 가장 흔한 원인균이다. Mycobacterium tuberculosis은 폐결핵을 일으키는 경우가 가장 흔하며, 활동성 폐결핵과 근골격계 결핵이 동반되는 경우는 약 30%이다. 근육내 결핵은 폐결핵을 일으키는 Mycobacterium tuberculosis가 근육 내로 침입하여 발병하는 것으로, 폐외 결핵 중 비교적 드문 형태이다. 저자들은 17개월 여아에서 다른 부위의 결핵을 동반하지 않은 근육내 결핵 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• The Korean Journal of Physiology and Pharmacology
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• 제21권6호
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• pp.687-694
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• 2017

Plumbagin, a hydroxy 1,4-naphthoquinone compound from plant metabolites, exhibits anticancer, antibacterial, and antifungal activities via modulating various signaling molecules. However, its effects on vascular functions are rarely studied except in pulmonary and coronary arteries where NADPH oxidase (NOX) inhibition was suggested as a mechanism. Here we investigate the effects of plumbagin on the contractility of skeletal artery (deep femoral artery, DFA), mesenteric artery (MA) and renal artery (RA) in rats. Although plumbagin alone had no effect on the isometric tone of DFA, $1{\mu}M$ phenylephrine (PhE)-induced partial contraction was largely augmented by plumbagin (${\Delta}T_{Plum}$, 125% of 80 mM KCl-induced contraction at $1{\mu}M$). With relatively higher concentrations (>$5{\mu}M$), plumbagin induced a transient contraction followed by tonic relaxation of DFA. Similar biphasic augmentation of the PhE-induced contraction was observed in MA and RA. VAS2870 and GKT137831, specific NOX4 inhibitors, neither mimicked nor inhibited ${\Delta}T_{Plum}$ in DFA. Also, pretreatment with tiron or catalase did not affect ${\Delta}T_{Plum}$ of DFA. Under the inhibition of PhE-contraction with L-type $Ca^{2+}$ channel blocker (nifedipine, $1{\mu}M$), plumbagin still induced tonic contraction, suggesting $Ca^{2+}$-sensitization mechanism of smooth muscle. Although ${\Delta}T_{Plum}$ was consistently observed under pretreatment with Rho A-kinase inhibitor (Y27632, $1{\mu}M$), a PKC inhibitor (GF 109203X, $10{\mu}M$) largely suppressed ${\Delta}T_{Plum}$. Taken together, it is suggested that plumbagin facilitates the PKC activation in the presence of vasoactive agonists in skeletal arteries. The biphasic contractile effects on the systemic arteries should be considered in the pharmacological studies of plumbagin and 1,4-naphthoquinones.

• 대한소아치과학회지
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• 제37권2호
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• pp.246-251
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• 2010

치아의 매복은 치배의 이상 위치 혹은 맹출로에 장애가 있어서 일어나지만, 그 정확한 기전은 아직 알려지지 않았다. 하악 제1대구치 매복의 발생율은 0.01~0.25%로 매우 드물지만, 이러한 매복은 인접 치아의 우식 또는 치근 흡수, 치조골의 저성장, 치주적 문제들을 일으킬 수 있기 때문에 최대한 빨리 매복을 해소시켜줄 필요가 있다. 매복된 하악 제1대구치가 근심경사 되어있을 경우 이를 직립시키기 위한 여러 생역학적 접근법이 있지만, 대부분의 방법들은 상호간의 힘(reciprocal force)에 의해 고정원 단위의 이동이 일어난다는 문제가 있다. 최근 골격성 고정원(SAS, Skeletal Anchorage System)의 도입으로 목표 치아 혹은 목표 분절에 직접적인 힘을 정확하게 전달할 수 있게 됨에 따라 단기간의 효율적 치아 이동이 가능하게 되었다. 본 증례에서는 만곡된 치근을 가진 매복 하악 좌측 제1대구치에서 치아의 직립을 위해 골격성 고정원인 miniplate를 사용 하였다. miniplate는 후구치 부위에 식립되었으며, 교정력을 적용한 10개월 후 매복치가 구강 내로 노출되고 직립되었다. 이에 하악 좌측 제1대구치를 고정성 교정장치에 포함시켜 정상 교합을 얻을 수 있었다.이와 같이 골격성 고정원을 사용함으로써 교정술식을 단순화시키고 교정치료 기간을 줄이며 부작용이 적었던 장점 등이 있어 보고하는 바이다.

• Journal of Animal Science and Technology
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• 제52권4호
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• pp.329-336
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• 2010

본 연구는 소의 부위별 근육에 특이하게 발현하는 유전자 마커를 발굴하여 소고기의 부위를 과학적으로 판명할 수 있는 기술을 개발하고자 실시하였다. 이러한 연구 목표 아래 먼저 사태(Beef shank), 등심(Longissimus dorsi), 양지(Deep pectoral), 홍두깨(Semitendinosus) 부위의 근육조직에서 MSC (myogenic satellite cell, 근육줄기세포)를 순수 분리하고 이를 MFC (myotube-formed cell; 근관이 형성된 세포)로 분화시키거나 ALC (adipocyte-like cell; 지방세포와 유사한 세포)로 이형분화 시킨 후 3가지의 세포로 부터 각각의 RNA를 추출하였다. 이렇게 추출한 RNA는 24,000개의 bovine oligo-nucelotide (70 mer)가 집적된 microarray를 이용해 4개의 조직 중 1개의 조직에서만 MSC의 분화(MFC) 또는 이형분화 과정에서 mRNA의 발현이 증감을 보이는 유전자 135개를 먼저 발굴하였다. 135개의 유전자에 대해 microarray 분석에 사용한 동일한 RNA를 이용하여 real-time PCR 기술로 검증한 결과 총 29개의 유전자가 microarray 분석 결과와 유사함을 보였다. 29개의 유전자를 다시 4개 부위의 생체 조직에서 추출한 RNA를 이용해 real-time PCR 방법으로 분석한 결과 TS (thymi- dlyate synthase), TE (tropoelastin), RAD52(similar RAD52 motifcontaining protein 1), unknown gene), MLC2 (myosin light 2, regulatory cardiac, slow), TXNIP (thioredoxin-interating protein) 6개의 유전자만이 다른 부위에 비해 사태 부위에서 현저한 발현의 차이를 나타냈다. 결론적으로 본 연구를 통해 소 부위별 근육을 구분할 수 있는 과학적 기술의 토대를 확립하였다.