• Korea-Australia Rheology Journal
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• 제17권3호
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• pp.125-130
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• 2005

Coalescence process of binary immiscible fluid mixtures having bimodal size distributions, prepared by mixing two pre-sheared samples at different shear rates, ${\gamma}_{pre1}\;and\;{\gamma}_{pre2}$, under shear flow at a final shear rate, ${\gamma}_f$, are examined by transient shear stress measurements and microscopic observations in comparison with the results for simply pre-sheared samples having narrow size distributions (unimodal distribution samples). Component fluids are a silicone oil (PDMS) and a hydrocarbon-formaldehyde resin (Genelite) and their viscosities are 14.1 and 21.0 $pa{\cdot}sec$ at room temperature $(ca.\;20^{\circ}C)$, respectively. The weight ratio of PDMS: Genelite was 7:3. Three cases, $({\gamma}_{pre1}=7.2sec^{-1},\;{\gamma}_{pre2}=12.0sec^{-1}\;and\;{\gamma}_f=2.4sec^{-1}),\;({\gamma}_{pre1}=0.8sec^{-1},\;{\gamma}_{pre2}=4.0sec^{-1}\;and\;{\gamma}_f=2.4sec^{-1}),\;and\;({\gamma}_{pre1}=7.2sec^{-1},\;{\gamma}_{pre2}=12.0^sec^{-1}\;and\;{\gamma}_f=7.2sec^{-1})$ the first case, transient shear stress did not show any significant difference but domains larger than the initial state are observed at short times. In the latter cases, there exist undershoot of shear stress, reflecting existence of deformed large domains, which is confirmed by the direct observation. It is concluded that coalescence between large and small domains more frequently occur than coalescence between the domains with similar size in the bimodal distribution samples.

• 한국약용작물학회지
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• 제22권1호
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• pp.46-52
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• 2014

In traditional Korean and Chinese medicine, safflower (Carthamus tinctorius L.) for the treatment of central nervous system-related symptoms such as tremor, seizure, stroke and epilepsy. We investigated the effects of safflower could influence cerebral ischemia-induced neuronal and cognitive impairments. Administration of safflower for 1 day (200 mg/kg body weight, p.o.) increased the survival of hippocampal CA1 pyramidal neurons after transient global brain ischemia. And neurological functions measured as short term memory. Post-treatment with safflower for 2 times decreased the induction/reduction - induced production of neuronal cell loss from global cerebral ischemia. Safflower markedly decreased neuronal cell death and also caused a decrease in the content of thiobarbituric acid-reacting substances (TBARS) ($55.2{\pm}9.4{\mu}mol\;mg^{-1}$) and significant improvement of activities of glutathione (GSH) ($27.2{\pm}5.0{\mu}mol\;mg^{-1}$) in hippocampus. We conclude that treatment with safflower attenuated learning and memory deficits, and neuronal cell loss induced by global cerebral ischemia. These results suggest that safflower may be a potential candidate for the treatment of vascular dementia.

• Molecules and Cells
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• 제27권2호
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• pp.167-173
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• 2009

The classical type of transient receptor potential (TRPC) channel is a molecular candidate for $Ca^{2+}$-permeable cation channels in mammalian cells. Because TRPC4 and TRPC5 belong to the same subfamily of TRPC, they have been assumed to have the same physiological properties. However, we found that TRPC4 had its own functional characteristics different from those of TRPC5. TRPC4 channels had no constitutive activity and were activated by muscarinic stimulation only when a muscarinic receptor was co-expressed with TRPC4 in human embryonic kidney (HEK) cells. Endogenous muscarinic receptor appeared not to interact with TRPC4. TPRC4 activation by $GTP{\gamma}S$ was not desensitized. TPRC4 activation by $GTP{\gamma}S$ was not inhibited by either Rho kinase inhibitor or MLCK inhibitor. TRPC4 was sensitive to external pH with $pK_a$ of 7.3. Finally, TPRC4 activation by $GTP{\gamma}S$ was inhibited by the calmodulin inhibitor W-7. We conclude that TRPC4 and TRPC5 have different properties and their own physiological roles.

• 한방비만학회지
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• 제18권2호
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• pp.57-63
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• 2018

Objectives: Metabolic syndrome is defined by a cluster of major cardiovascular risk factors: obesity, insulin resistance, dyslipidemia, and arterial hypertension. Several members of a large family of nonselective cation entry channels, e.g., transient receptor potential vanilloid 4 (TRPV4) channels have been associated with the development of dyslipidemia and hypertension. The purpose of this study was to investigate the effects of Leejung-tang (Lizhong-tang), Rikkunshito, and Bojungikgi-tang (Buzhongyiqi-tang) on TRPV4 channel. Methods: Human embryonic kidney 293 cells stably transfected with the TRPV4 expression vectors were maintained in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, $5{\mu}g/mL$ blasticidin, and 0.4 mg/mL zeocin in a humidified 20% $O_2/10%$ $CO_2$ atmosphere at $37^{\circ}C$. Whole-cell patch clamp recordings were obtained using an Axopatch 700B amplifier and pClamp v.10.4 software (Molecular Devices, San Jose, CA, USA), and signals were digitalized at 5 kHz using Digidata 1422A. Results: Leejung-tang and Rikkunshito (10, 30 and 50 mg/mL) had no effects on the TRPV4 whole-cell currents at dose dependent manner. However, Bojungikgi-tang (10, 30, and 50 mg/mL) inhibited the TRPV4 whole-cell currents in a dose dependent manner and the half maximal inhibitory concentration (IC50) of Bojungikgi-tang was 18.2 mg/mL. Conclusions: These results suggest that Bojungikgi-tang plays an important roles to inhibit the TRPV4 channel, suggesting that Bojungikgi-tang is considered one of the candidate agents for the treatment of metabolic syndrome such as dyslipidemia and hypertension.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권1호
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• pp.36-41
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• 2006

Objective. The objective of this study was to examine the hypothesis that inflammatory synovial fluid from TMJ internal derangement initiates a transient increase in intracellular calcium concentration ([$Ca^{2+}$]i) in chondrocytes and the induced Ca2+ signaling affects iNOS/COX-2 gene expression patterns following exposure to inflamed synovial fluid. Materials and Methods. Two female adult patients with symptoms of TMD who agreed to participate in the study were selected for this study. Immortalized human juvenile costal chondrocyte C-28/I2 was grown to 80% confluency and synovial fluids from two patients were added respectively to culture media for 24 hours at the concentration of 100ng/10ml. Confocal laser scanning microscope (CLSM) was used to examine changes of intracellular calcium concentration ([$Ca^{2+}$]i). RT-PCR was performed to identify the expression profile of IL-1${\alpha}$, iNOS, COX-2. Results. Increased [$Ca^{2+}$]i was observed in chondrocytes subjected to inflamed synovial fluid compared to control cultures and in respective cultures exposed to inflamed synovial fluids from each patient, IL-1${\beta}$, COX-2 mRNA were detected. However, in neither case iNOS mRNA was expressed. IL-1${\alpha}$, COX-2, and iNOS mRNA were expressed in control culture. Conclusion. Our results show that immortalized chondrocytes cultured with inflamed synovial fluids from patients diagnosed as disc displacement without reduction and limitation in mouth opening showed increased calcium concentration and expression of COX-2 while inhibiting the production of iNOS, which in turn could adversely affect the chondrocytes in at least short term by hindering physiologic role of NO against inflammatory cascades. These findings suggest that inflamed synovial fluid may differentially regulate the transcriptomes of relevant inflammatory mediators, especially iNOS/COX-2 axis in chondrocytes through adjusting calcium transients.

• 대한약리학회지
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• 제32권3호
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• pp.323-334
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• 1996

웅성 모래쥐의 양경동맥을 7분간 폐쇄하여(OBC7) 뇌의 허혈을 유발하여, 해마의 microdialysate내 polyamine 함량과 조직내 polyamine 생합성효소(ornithine decarboxylase: ODC와 S-adenosylmethionine decarboxylase: SAM-DC)의 활성도를 분석하고, 해마의 cresyl violet(CV) 염색과 glial fibrillary acidic protein(GFAP) 면역염색소견들을 관찰하여, 허혈성 해마의 신경손상과 polyamine대사의 연관성을 검토하였다. 1) OBC부하 후, 해마의 dialysate내 polyamine 변동에서, putrescine(PT)은 현저히 증가되었으나, spermidine과 spermine은 다소 감소되는 경향을 보였고, 이에 해마조직내 ODC활성의 현저한 상승과 SAM-DC활성도의 유의한 저학 동반되었다. 2) Difluoromethylornithine(DFMO)는 OBC에 의한 PT증가와 ODC활성도 상승을 유의하게 억제하였으나, methylglyoxal bis(guanylhydrazone)(MGBG)는 각각 다소 억제하는 경향을 보였다. 3) OBC부하 7일후에 관찰한 조직소견에서, 해마의 CA1 부위의 유의한 신경손상이 유도되었으나 CA3와 dentate gyrus 부위에는 미약한 손상만 보였으며, GFAP 양성반응도 CA1 부위에서만 유의한 증가를 보였다. 이같은 소견들은 DFMO에 의하여 크게 영향을 받지 않았으나 MGBG에 의하여 유의하게 억제되었다. 이상의 성적들은 해마 polyamine의 과도한 허혈성 증가가 허혈성 신경손상에 관여할 수 있으나, 한편으로 polyamine대사의 과도한 억제도 허혈성 신경손상을 악화시킬 수 있으며, 허혈성뇌손상에 대한 MGBG의 보호작용은 polyamine 대사보다는 다른 작용에 매개되는 것으로 사료된다. 가장 많았고 습진과 소양증이 각각 19.5%였다. 30대 환자군에서는 습진이 30.3%였고 소양증이 19.1%였다. 40대에서는 소양증이 28.8%였고 지루성 피부염이 16.0%였다. 50대에서는 습진이 26.7%였고 60세 이상의 그룹에서는 습진이 50.0%, 바이러스 질환과 소양증이 각각 15.0%였다. 이들 결과는 통계적으로 유의한 차이를 보였다($X^2\;=\;74.995^{**}$, p = .001, df : 40). 결론 : 상대적으로 50세 이상 연령충의 대상 환자 수가 많지 않은 원인은 여리 가지 분석이 가능할 것으로 생각된다. 연령에 따라 피부질환이 다른 양상을 보임을 고려할 때 노인층의 신체적, 경제적, 사회적 특성을 이해하고 이에 따른 효과적이고 사회-경제학적 부담을 최소할 수 있는 한방 치료 영역의 확대 및 개발이 필요할 것으로 사려된다.주식 및 후식의 선호도에 남녀 간에 차이를 보이고 있으므로 단체급식을 위한 식단 작성 시 이러한 차이를 고려할 필요가 있으며 대학생 및 성인을 대상으로 한 영양 교육을 실시할 때 이러한 차이를 고려한 신생활 교정프로그램을 작성할 필요가 있다고 사료된다.$은 대조군에 비해 발아에 의하여 세포독성 효과를 증가되었지만, MCF-7와 Caco-2에 대한 항암효과는 없음을 알 수 있었다.것으로 사료된다.높게 인식할수록 재방문의도 및 추천의도가 커지는 것을 알 수 있었다. 대학교 급식소 운영주체에 대한 소비자 인지도 조사결과 향후 대학교 급식소를 운영하는 위탁급식 전문업체의 경우 그들의 브랜드를 알리기 위한 홍보전략이 절실히 필요함을 알 수 있었으며, 최근고객감소로 인하여 다양한 급식운영 마케팅전략을 수립하고 있는 단체급식 운영자들은 재방문 및 추천의도의 선행요건이 급식서비스 품질에 대한 소비자의 인식임을 명심하여 가장 기본이 되는 급식서비스 품질수준을 향상시키기 위하여 노력하여야 할 것이다.

• 대한한의학회지
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• 제30권2호
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• pp.1-16
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• 2009

Objectives: This study investigated the effect of Yukmijihwangtang on cerebral ischemia-induced learning and memory impairment by middle cerebral artery (MCA) occlusion in rats. Methods: The ability of learning and memory of rats was measured using the eight-arm radial maze and the passive avoidance test, and profile of cholinergic neuron was assessed in the medial septum and hippocampus region by immuno-histochemistry. Results: 1. No differences were found between groups in the number of correct choices in acquisition performance during the eight-arm radial maze task. 2. No differences were found between groups on day 1 in the error rate in acquisition performance, which is defined as the number of enters into the same arm more than once within five minutes. After 5 to 6 days of test, the number of errors was significantly reduced in the Yukmijihwangtang group (forebrain ischemia group with Yukmijihwangtang treatment), compared with the ischemia group. 3. The memory processes significantly improved in the Yukmijihwangtang group according to results of the passive avoidance test. 4. The appearance of AchE (acetylcholinesterase) in the CA1 region of hippocampus significantly decreased in the ischemia group, compared with the sham group (untreated group). The appearance of AchE in the same region significantly increased in the Yukmijihwangtang group, compared with the ischemia group. 5. The appearance of ChAT (choline acetyltransferase) in the CA1 region of the hippocampus and medial septum decreased in the ischemia group, compared with the sham group. The appearance of ChAT in the same region significantly increased in the Yukmijihwangtang group, compared with the ischemia group Conclusions: This study provides evidence that Yukmijihwangtang is effective for reviving the ability of learning and memory and damaged neurons in rats with experimental cerebral ischemia.

• The Korean Journal of Physiology and Pharmacology
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• 제12권6호
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• pp.337-342
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• 2008

Human bone marrow mesenchymal stem cells (hBM-MSCs) represent a potentially valuable cell type for clinical therapeutic applications. The present study was designed to evaluate the effect of long-term culturing (up to $10^{th}$ passages) of hBM-MSCs from eight individual amyotrophic lateral sclerosis (ALS) patients, focusing on functional ion channels. All hBM-MSCs contain several MSCs markers with no significant differences, whereas the distribution of functional ion channels was shown to be different between cells. Four types of $K^+$ currents, including noise-like $Ca^{+2}$-activated $K^+$ current ($IK_{Ca}$), a transient outward $K^+$ current ($I_{to}$), a delayed rectifier $K^+$ current ($IK_{DR}$), and an inward-rectifier $K^+$ current ($K_{ir}$) were heterogeneously present in these cells, and a TTX-sensitive $Na^+$ current ($I_{Na,TTX}$) was also recorded. In the RT-PCR analysis, Kv1.1,, heag1, Kv4.2, Kir2.1, MaxiK, and hNE-Na were detected. In particular, ($I_{Na,TTX}$) showed a significant passage-dependent increase. This is the first report showing that functional ion channel profiling depend on the cellular passage of hBM-MSCs.

• 한국임상수의학회지
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• 제22권3호
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• pp.220-227
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• 2005

Although ketamine has been used in the field of anesthetic medicine for its safety and favourable respiratory effects, the cardiovascular effects of ketamine is still controversial. To clarify the action and mechanism of ketamine upon cardiovascular system, arterial blood pressure, tension of aortic ring, left ventricular developed pressure and heart rate were measured in rats, Ketamine produced two types of effects on arterial blood pressure in anesthetized rats; monophasic effect (blood pressure lowering) and biphasic effect (initial transient blood pressure increasing following sustained lowering), The ketamine-induced lowering of aterial blood pressure showed a concentration-dependent manner, inhibited by the pretreament of $MgCl_2$ and potentiated by the pretreatment of $CaCl_2$. The ketamine-induced lowering of aterial blood pressure was suppressed by the pretreatment of nifedipine, verapamil or lidocaine. In phenylephrine-precontracted endothelium intact (+E) aortic rings, ketamine sometimes caused a small enhancement of contraction ($112.5{\pm}3.6{\%}$). However, in many experiments, ketamine produced a concentration-dependent relaxation in +E aortic rings precontracted with either phenylephrine or KCl. Ketamine-induced relaxation was significantly greater in KCl-precontracted strips than phenylephrine-precontracted strips. In phenylephrine-precontracted +E aortic rings, the ketamine-induced vasorelaxation was not suppressed by endothelium removal or by the pretreatment of a nitric oxide synthase inhibitors, L-$N^G$-nitro-arginine and a guanylate cyclase inhibitors, methylene blue, suggesting that the ketamine-induced vasorelaxation is not dependent on the endothelial function. In addition, ketamine elicited an increase in left ventricular developed pressure in perfused hearts accompanied by decrease in heart rate. These results suggest that ketamine could evoke a hypotension due to vasorelaxation and decrease in heart rate in rats. The inhibitory effect of cardiovascular system might be associated with modulation of $Ca^{2+}$ homeostasis.

• 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.