• Journal of Ginseng Research
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• 제31권2호
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• pp.69-73
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• 2007

Since chemical structures of ginsenoside as active ingredient of Panax ginseng are known, accumulating evidence have shown that ginsenoside is one of bio-active ligands through the diverse physiological and pharmacological evaluations. Chemical structures of ginsenoside could be divided into three parts depending on diol or triol ginsenoside: Steroid- or cholesterol-like backbone structure, carbohydrate portions, which are attached at the carbon-3, -6 or -20, and aliphatic side chain coupled to the backbone structure at the carbon-20. Ginsenosides also exist as stereoisomer at the carbon-20. Bioactive ligands usually exhibit the their structure-function relationships. In ginsenosides, there is little known about the relationship of chemical structure and biological activity. Recent reports have shown that ginsenoside $Rg_3$, one of active ginsenosides, exhibits its differential physiological or pharmacological actions depending on its chemical structure. This review will show how ginsenoside $Rg_3$, as a model compound, is functionally coupled to voltage-gated ion channel or ligand-gated ion channel regulations in related with its chemical structure.

• 전기전자학회논문지
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• 제24권4호
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• pp.1039-1049
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• 2020

신경의수를 제어하기 위해서는 사용자의 의도를 인식하는 신경신호 디코딩이 중요하다. 본 논문에서는 다채널 말초 신경신호의 실시간 디코딩 방법을 제안한다. 말초 신경신호는 정중신경과 요골신경에서 측정되었으며 운동잡음은 국소 근사 다항식에 의해 제거되었다. 다음으로 활동전위는 k-평균 알고리즘으로 분류되었다. 특징벡터는 활동전위의 발화율로부터 추출되었으며 자기 조직화 특징지도를 통해 차원이 축소되었다. 마지막으로 다층 퍼셉트론으로 손동작을 분류하였다. 원숭이 실험에서 모든 신호처리가 실시간 제한조건 이내에 완료되었으며 높은 성공률로 손동작을 인식할 수 있었다.

• 재활복지공학회논문지
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• 제10권4호
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• pp.279-285
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• 2016

신경보철 의수를 제어하기 위해서는 말초 신경신호를 측정하고 분석함으로써 사용자의 동작의도를 인식해야 한다. 본 논문에서는 다채널 신경전극 어레이, 전극 삽입 장치, 신경신호 증폭기로 구성된 말초 신경신호 측정 시스템을 제안한다. 마취상태에서 전극 삽입 장치를 이용하여 16 채널의 신경전극 어레이를 백서의 좌골신경에 안정적으로 삽입하였다. 수동적 관절 운동을 유도하거나 기계적 피부 자극을 인가하였을 때, 신경신호 증폭기를 통해 근육 또는 피부 감각 신경신호가 측정됨을 확인하였다. 또한, 개별 신경 단위를 분리하기 위해 활동전위 분류방법을 제안한다. 근육의 내부 수용기들은 근방추와 골지건 기관 수용기로 구분되었으며, 피부의 외부 수용기들은 완만적응과 급속적응 수용기로 분리되었다. 이와 같은 실험결과는 제안한 방법이 신경보철 시스템에서 말초 신경신호의 측정과 분석에 적용될 수 있음을 보였다.

• 대한약침학회지
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• 제16권2호
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• pp.55-61
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• 2013

Objective: Ulmi Pumilae Cortex (UPC) is a deciduous tree with uneven pinnate leaves and is classified as a subfamily of Ulmuceae and contains many pharmacologically active constituents. The aim of this study was to investigate the effects of UPC on the growth and survival of AGS cells, the most common human gastric adenocarcinoma cell lines. Methods: The AGS cells were treated with varying concentrations of UPC. Analyses of the sub G1, caspase-3 activity, and mitochondrial depolarization were conducted to determine whether AGS cell death occured by apoptosis. Furthermore, to identify the role of the transient receptor potential melastatin (TRPM) 7 channels in AGS cell growth and survival, we used human embryonic kidney (HEK) 293 cells overexpressed with TRPM7 channels. Results: The addition of UPC to a culture medium inhibited AGS cell growth and survival. Experimental results showed that the sub G1, caspase-3 activity, and mitochondrial depolarization were increased. Furthermore, TRPM7 channel overexpression in HEK 293 cells exacerbated UPC-induced cell death. Conclusion: These findings indicate that UPC inhibits the growth and survival of gastric cancer cells due to a blockade of the TRPM7 channel activity. Therefore, UPC is a potential drug for treatment of gastric cancer, and TRPM7 channels may play an important role in survival in cases of gastric cancer.

• 한국의류학회지
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• 제30권5호
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• pp.788-799
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• 2006

The purpose of this study was to analyze fashion merchandising process, to apply customer information in merchandising process and to examine customer management strategies of fashion industry in on-line and off-line channel. In depth, face to face interviews with structured questionnaires were conducted with MD and customer managers from selected 4 brands, one from each categories of men's, women's, casual and sports wear. Key findings of the study were as follows: First, they followed fashion merchandising process of 18 steps and collected trend information and sales data were applied to planning, selling/promoting process to plan season concept, design, and promotion activity. Second, commonly applied customer information types in fashion merchandising process were all from indirect information collected from sales data and forecasting companies. However, casual and sports wear conducted consumer monitoring activity f3r collecting customer data directly from customer participation. Third, in off-line channel, customers are segmented by amount of purchase they make in a specific time period and all the categories show high interest in valuable customers. However, only men's and woman's wear conducted promotion activities for valuable customers as a differentiated marketing strategy. In on-line channel, companies were interacting with the customers through internet web site to determine their demands. In conclusion, this study has significance in that it propose the necessity and strategy of differentiated customer management approaching by analyzing and comparing fashion merchandising activity process cases.

• BMB Reports
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• 제52권7호
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• pp.445-450
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• 2019

TTYH2 is a calcium-activated, inwardly rectifying anion channel that has been shown to be related to renal cancer and colon cancer. Based on the topological prediction, TTYH2 protein has five transmembrane domains with the extracellular N-terminus and the cytoplasmic C-terminus. In the present study, we identified a vesicle transport protein, ${\beta}$-COP, as a novel specific binding partner of TTYH2 by yeast two-hybrid screening using a human brain cDNA library with the C-terminal region of TTYH2 (TTYH2-C) as a bait. Using in vitro and in vivo binding assays, we confirmed the protein-protein interactions between TTYH2 and ${\beta}$-COP. We also found that the surface expression and activity of TTYH2 were decreased by co-expression with ${\beta}$-COP in the heterologous expression system. In addition, ${\beta}$-COP associated with TTYH2 in a native condition at a human colon cancer cell line, LoVo cells. The over-expression of ${\beta}$-COP in the LoVo cells led to a dramatic decrease in the surface expression and activity of endogenous TTYH2. Collectively, these data suggested that ${\beta}$-COP plays a critical role in the trafficking of the TTYH2 channel to the plasma membrane.

• 한국가시화정보학회지
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• 제15권3호
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• pp.27-33
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• 2017

Direct numerical simulations of turbulent channel flows with moving wall conditions on the top wall are performed to examine the effects of the moving wall on the turbulent characteristics. The moving wall velocity only applied to the top wall with the opposite direction to the main flow is systematically varied to reveal the sustained-mechanism for turbulence. The turbulence statistics for the Couette-Poiseuille flow, such as mean velocity, root mean square of the velocity fluctuations, Reynolds shear stress and pre-multiplied energy spectra of the velocity fluctuations, are compared with those of canonical turbulent channel flows. The comparison suggests that although the turbulent activity on the top wall increases with increasing the Reynolds number, that on the bottom wall decreases, contrary to the previous finding for the canonical turbulent channel flows. The increase of the turbulent energy on the top wall is attributed to not only the increase of the Reynolds number but also elongation of the logarithmic layer due to increase of the wall layer on the top wall. However, because the logarithmic layer is shortened on the bottom wall due to the decrease of the wall layer, the turbulence energy on the bottom wall decreases despite of the increase of the Reynolds number.

• Journal of Ginseng Research
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• 제29권1호
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• pp.19-26
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• 2005

The last two decades have shown a marked expansion in publications of diverse effects of Panax ginseng. Ginsenosides, as active ingredients of Panax ginseng, are saponins found in only ginseng. Recently, a line of evidences shows that ginsenosides regulate various types of ion channel activity such as $Ca^{2+},\;K^+,\;Na^+,\;Cl^-$, or ligand gated ion channels (i.e. $5-HT_3$, nicotinic acetylcholine, or NMDA receptor) in neuronal, non-neuronal cells, and heterologously expressed cells. Ginsenosides inhibit voltage-dependent $Ca^{2+},\;K^+,\;and\;Na^+$ channels, whereas ginsenosides activate $Ca^{2+}-activated\;Cl^-\;and\;Ca^{2+}-activated\;K^+$ channels. Ginsenosides also inhibit excitatory ligand-gated ion channels such as $5-HT_3$, nicotinic acetylcholine, and NMDA receptors. This review will introduce recent findings on the ginsenoside-induced differential regulations of ion channel activities and will further expand the possibilities how these ginsenoside-induced ion channel regulations are coupled to biological effects of Panax ginseng.

• Journal of Ginseng Research
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• 제29권1호
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• pp.37-43
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• 2005

We performed in vitro and in vivo studies to know whether the inhibitory effects of ginsenosides on $5-HT_{3A}$ receptor channel acctivity are coupled to anti-nausea and anti-vomiting action. In vitro study, we investigated the effect of compound K (CK) and M4, which are ginsenoside metabolites, on human $5-HT_{3A}$ receptor channel activity expressed in Xenopus oocytes using two-electrode voltage clamp technique. Treatment of CK or M4 themselves had no effect in both oocytes injected with $H_2O\;and\;5-HT_{3A}$ receptor cRNA. In oocytes injected with $5- HT_{3A}$ receptor cRNA, M4 treatment inhibited more potently 5-HT-induced inward peak current $(I_{5-HT})$ than CK with dose-dependent and reversible manner. The half-inhibitory concentrations $(IC_{50})$ of CK and M4 were $36.9\;\pm\;10.1\;and\;7.3\;\pm\;2.2\;{\mu}M$, respectively. The inhibition of $I_{5-HT}$ by M4 was non-competitive and voltage-independent. These results indicate that M4 might regulate $5-HT_{3A}$ receptors. In vivo experiments, injection of cisplatin (7.5 mg/kg, i.v.) induced both nausea and vomiting with 1 h latency. These episodes reached to peak after 2 h and persisted for 4 h. Pre-treatment of GTS (500 mg/kg, p.o.) significantly reduced cisplatin-induced nausea and vomiting by $51\;\pm\;8.4\;and\;48.8\;\pm\;6.4\%$ during 4 h compared to GIS­untreated group, respectively. These results show the possibility that in vitro inhibition of $5-HT_{3A}$ receptor channel activity by ginsenosides might be coupled to in vivo anti-emetic activity.

• The Korean Journal of Physiology and Pharmacology
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• 제24권3호
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• pp.277-286
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• 2020

Polycystic kidney disease 2-like-1 (PKD2L1), also known as polycystin-L or TRPP3, is a non-selective cation channel that regulates intracellular calcium concentration. Calmodulin (CaM) is a calcium binding protein, consisting of N-lobe and C-lobe with two calcium binding EF-hands in each lobe. In previous study, we confirmed that CaM is associated with desensitization of PKD2L1 and that CaM N-lobe and PKD2L1 EF-hand specifically are involved. However, the CaM-binding domain (CaMBD) and its inhibitory mechanism of PKD2L1 have not been identified. In order to identify CaM-binding anchor residue of PKD2L1, single mutants of putative CaMBD and EF-hand deletion mutants were generated. The current changes of the mutants were recorded with whole-cell patch clamp. The calmidazolium (CMZ), a calmodulin inhibitor, was used under different concentrations of intracellular. Among the mutants that showed similar or higher basal currents with that of the PKD2L1 wild type, L593A showed little change in current induced by CMZ. Co-expression of L593A with CaM attenuated the inhibitory effect of PKD2L1 by CaM. In the previous study it was inferred that CaM C-lobe inhibits channels by binding to PKD2L1 at 16 nM calcium concentration and CaM N-lobe at 100 nM. Based on the results at 16 nM calcium concentration condition, this study suggests that CaM C-lobe binds to Leu-593, which can be a CaM C-lobe anchor residue, to regulate channel activity. Taken together, our results provide a model for the regulation of PKD2L1 channel activity by CaM.