• Biomolecules & Therapeutics
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• 제12권2호
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• pp.92-100
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• 2004

Effect of the depletion or oxidation of GSH on mitomycin c (MMC)-induced mitochondrial damage and cell death was assessed in small cell lung cancer (SCLC) cells. MMC induced cell death and the decrease in the GSH contents in SCLC cells, which were inhibited by z-LEHD.fmk (a cell permeable inhibitor of caspase-9), z-DQMD.fmk (a cell permeable inhibitor of caspase-3) and thiol compound, N-acetylcysteine. MMC caused nuclear damage, release of cytochrome c and activation of caspase-3, which were reduced by N-acetylcysteine. The depletion of GSH due to L-butionine-sulfoximine enhanced the MMC-induced cell death and formation of reactive oxygen species in SCLC cells, whereas the oxidation of GSH due to diamide or $NH_2Cl$ did not affect cytotoxicity of MMC. The results show that MMC may cause cell death in SCLC cells by inducing mitochondrial dysfunction, leading to activation of caspase-9 and -3. The MMC-induced change in the mitochondrial membrane permeability, followed by cell death, in SCLC cells may be significantly enhanced by the depletion of GSH. In contrast, the oxidation of GSH may not affect cytotoxicity of MMC.

• 생명과학회지
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• 제21권10호
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• pp.1385-1392
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• 2011

SOCS-3와 IGF-I은 근육의 분화 과정 및 근비대 기전에 있어 매우 중요한 조절자 역할을 하는 유전자 및 성장인 자이며, 최근 골격근에서 IGF-I과 SOCS-3 유전자의 상호작용에 관한 연구의 필요성이 제기되고 있다. 본 연구에서는 C2C12 myotube에서 IGF-I이 SOCS-3 유전자 발현에 미치는 영향에 대해 알아보기 위해 4일간 분화시킨 C2C12 myotube에 IGF-I을 다양한 농도(0-200 ng/ml) 및 시간(3-72 시간)에 따라 처리하였다. 그 결과 IGF-I이 SOCS-3 유전자의 단백질 발현을 시간 의존적으로 유의하게 증가시켰으며, 3 시간에서 mRNA 발현을 증가시키고, 시간이 지남에 따라 긴 시간에서는 농도 의존적으로 발현이 감소하였음을 알 수 있었다. 또한 면역형광 염색을 통해 IGF-I이 myotube에서 SOCS-3의 단백질을 발현 시켰음을 뚜렷하게 관찰 할 수 있었다. 위 결과들을 바탕으로 본 연구에서는 IGF-I의 처리가 분화된 근육 세포인 C2C12 myotube에서 SOCS-3 유전자 발현에 유의한 영향을 미쳤음을 증명하였다. 이러한 결과는 선행연구에서 보고한 운동이 SOCS-3 유전자 발현을 증가시킴에 있어서 IGF-I이 중추적인 역할을 한 것으로 생각된다. 그러나 IGF-I에 의한 SOCS-3 유전자 발현 조절 기전에 있어 관련 신호 전달체계 및 골격근 관련 유전자 발현에 미치는 영향에 관한 연구는 보다 더 이루어져야 할 것이라 사료된다.

• 한국미생물·생명공학회지
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• 제19권4호
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• pp.390-397
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• 1991

효모를 Ca-alginate에 고정화하여 회분발효에서 glucose로부터 에탄올을 생산하여 다음의 결과를 얻었다. 100g wet weight/l($4.3 \times 10^9$ cell/l)의 효모를 pH 7.0, 2% 농도의 Ca-alginate에 고정화하였다. 10 beads volume이 에탄올 생산에 최적이었고 30일 (720 시간) 동안 bead의 수명이 지속되었다. 회분식 발효에서 온도안정성은 고정화 효모의 경우 30~$40^{\circ}C$였으며 free cell의 경우 30~$37^{\circ}C$였다. pH 안정성은 pH 4.0~9.0였으며, 에탄올생산 최적 당농도는 15%였다. 최적조건에서 에탄올수율은 0.45, 생산된 에탄올 농도는 67.6g/l 그리고 에탄올 생산성은 1.99g/l.h로 각각 나타났다.

• Biomolecules & Therapeutics
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• 제8권2호
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• pp.140-146
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• 2000

Recently, we reported that immunostimulation of primary rat cortical astrocyte caused stimulation of glucose deprivation induced apoptotic cell death. To enhance the understanding of the mechanism of the potentiated cell death of clucose-deprived astrocyte by immunostimulation, we investigated the effect of immunostimulation on the glucose deprivation induced cell death of rat C6 glioma cells. Co-treatment of C6 glioma cells with lipopolysaccharide (LPS, $1\;{\mu}\textrm{g}/ml$) and interferon ${\gamma}(IFN{\gamma},\;100U/ml)$ is serum free condition caused marked elevationo f nitric oxide production ($>50\;{\mu}M$). In this condition, glucose deprivation caused significant release of lactate dehdrogenase (LDH) from C6 glioma cells while control cells did not show LDH release. To investigate whether elevated level of nitric oxide is responsible for the enhanced LDH release in glucose-deprived condition, C6 glioma cells were treated with 3-morphorinosydnonimine (SIN-1) and it was observed that SIN-1 caused increase in LDH release from glucose-deprived C6 glioma cells. Treatment of C6 glioma cells with $25\;{\mu}M$ of pyrrolidinedithiocarbamate (PDTC) which inhibit Nuclear factor kB (NF-kB) activation, caused complete inhibition of nitric oxide production. Treatment of C6 glioma cells with NO synthase inhibitors, $N^{G}$-nitro-L-arginine (NNA) or L-$N{\omega}$-nitro-L-arginine methyl ester (L-NAME), caused inhibition of nitric oxide production and also glucose deprivation induced cell death of cytokine-stimulated C6 glioma cells. In addition, diaminohydroxypyrimidine (DAHP, 5 mM) which inhibits the synthesis of tetrahydrobiopterine (BH4), one of essential cofactors for iNOS activity, caused complete inhibition of NO production from immunostimulated C6 glioma cells. The results from the present study suggest that immunostimulation causes potentiation of glucose deprivation induced death of C6 glioma cells which is mediated at least in part by the increased production of nitric oxide. The vulnerability of immunostimulated C6 glioma cells to hypoglycemic insults may implicate that the elevated level of cytokines in various ischemic and neurodegenerative diseases may play a role in their pathogenesis.

• 한국식품영양과학회지
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• 제25권3호
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• pp.399-405
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• 1996

The effects of stearic(18 : 0, SA), oleic(18 : 1 cis, OA) and elaidic acid(18 : 1 trans, EA) on the cell growth, contents of cellular lipids, and the fatty acid composition of cellular and medium lipids in Hep-G$_2$cells were evaluated. The cells were incubated in serum-free medium containing 25, 50, 100 and 200$\mu$M of a fatty acid combined with albumin for 2 days. The fatty acid concentration up to 100$\mu$M showed the normal growth, but the cell growth decreased in the presence of 200$\mu$M fatty acid. The treatment of cells with 100$\mu$M of a fatty acid for two days significantly(p<0.05) increased the cellular triglyceride(TG) content in all fatty acid groups compared to control, but TG contents was not significantly different among all treatment group, but total cholesterol(TC) was the highest level in EA group. The level of free cholesterol(FC) and cholesteryl ester(CE) was similar to those of TC in all fatty acid treated group. The cellular phospholipid(PL) contents were similar between the control and all fatty acid groups. The treatment of cells with SA has no notable effects on the fatty acid composition of TG, CE and PL. The OA treatment caused significant increases in CE(51.2%) and PL(29.8%), but not in TG. The EA treatment resulted in 10.1, 10.7 and 7.8% of $C_{18:1\;trans}$ content in cellular TG, CE, and PL. The TG, CE and PL of medium were relatively similar between SA and OA groups. In EA treated group, TG, CE and PL of medium contained 17.0%, 0.7% and 5.6% of $C_{18:1\;trans}$, respectively.

• KSBB Journal
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• 제8권5호
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• pp.452-456
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• 1993

Pichia stipitis CBS 5776에 의한 xylose의 최적 알코올 발효조건에 대한 연구를 수행하였다. 최적 세포성장 및 최대 ethanol 생성은 초가 pH가 5.0인 100 g/l 의 xylose배지를 이용하여 $30^{\circ}C$에서 0.05VVM으로 통기하고 300rpm으로 교반하는 발효 조건에셔 얻을 수 있었다. 이러한 최적 발효조건 서의 최대 비성장속도와 최대 세포농도는 각각 $0.14hr^{-1}$와 $1.3\times109$ cells/ml이였다. 또한 최대 etha­n nol 농도는 72시간 발효시에 100 g/l 의 xylose 중 에셔 96%을 이용하여 40.2 g/l 을 얻었으며, 이때 의 단위부피당 ethanol 생산성은 0.56 g/l-hr이고 ethanol 수율은 0.42g-ethanol/g-xylose로서 이론수율의 82%였다.

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2247-2254
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• 2010

The surface structures of copper phthalocyanine (CuPc) thin films deposited on sulphur-passivated and plane perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA)-covered InAs(100) surfaces have been studied by low energy electron diffraction (LEED) and van der Waals (vdW) intermolecular interaction energy calculations. The annealing to $300^{\circ}C$ and $450^{\circ}C$ of $(NH_4)_2S_x$-treated InAs(100) substrates produces a ($1{\times}1$) and ($2{\times}1$) S-passivated surface respectively. The CuPc deposition onto the PTCDA-covered InAs(100) surface leads to a ring-like diffraction pattern, indicating that the 2D ordered overlayer exists and the structure is dominantly determined by the intermolecular interactions rather than substrate-molecule interactions. However, no ordered LEED patterns were observed for the CuPc on S-passivated InAs(100) surface. The intermolecular interaction energy calculations have been carried out to rationalise this structural difference. In the case of CuPc unit cells on PTCDA layer, the planar layered CuPc structure is more stable than the $\alpha$-herringbone structure, consistent with the experimental LEED results. For CuPc unit cells on a S-($1{\times}1$) layer, however, the $\alpha$-herringbone structure is more stable than the planar layered structure, consistent with the absence of diffraction pattern. The results show that the lattice structure during the initial stages of thin film growth is influenced strongly by the intermolecular interactions at the interface.

• 한국수정란이식학회지
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• 제20권1호
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• pp.71-77
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• 2005

Relaxin과 insulin이 돼지 난포 과립막세포의 스테로이드 호르몬 분비에 미치는 영향을 연구하기위하여 체외에서 황체화된 과립막세포에서 prosesterone과 $17{\beta}-estradiol$의 생산을 조사하였다. 돼지난포 과립막세포를 혈청 존재하에 배양접시에 부착 후 48시간 동안 체외배양하고 무혈청 배지에서 24시간 배양하였다. Relaxin과 insulin의 용량의존성을 확인하기 위하여 다양한 농도 (10, 100, 1,000 ng/ml)를 각각 무혈청 배지에 첨가하였다. 병합 효과를 알아보기 위하여 100 ng/ml relaxin과 100 ng/ml insulin을 단독 혹은 병합하여 처리하였는데 황체호르몬 (100 ng/ml)을 처리한 경우와 처리하지 않은 경우 모두를 조사, 분석하였다. 최종 배양이 끝난 배양액을 수집하여 RIA법으로 proses-terone과 $17{\beta}-estradiol$의 농도를 조사하였다. Relaxin과 insulin은 용량이 증가될수록 progesterone의 생산을 증가시켰으나 $17{\beta}-estradiol$의 생산에는 아무런 영향이 없었다. 병합실험에서는 relaxin과 insulin 단독 또는 병합시 황체호르몬 존재 하에서 progesterone의 생산을 증가시켰으나 $17{\beta}-estradiol$의 생산에는 아무런 영향이 없었다. 결론적으로 relaxin과 insulin은 돼지 황체화 과립막세포의 progesterone 분비를 증가시키지만 $17{\beta}-estradiol$의 생산에는 효과가 없었으며 병합에 의한 상승효과는 없었다. Progesterone 생산에 미치는 relaxin과 insulin의 효과는 황체호르몬의 존재에 의해 증대되었다.

• 태양에너지
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• 제5권2호
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• pp.46-53
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• 1985

Hydrogenated amorphous silicon solar cells which are fabricated by photo-chemical vapor deposition (photo-CVD) system has been investigated. In the photo-CVD system which consists of three separate reaction chambers, low-pressure mercury lamp has been used as a light source. The main reactant ($Si_2H_6/He$) gases which are premixed with a small amount of mercury vapor in a mercury-vaporizer kept at $50^{\circ}C$ have been used. Using $C_2H_2$ and $SiH_2(CH_3)_2$ as the carbon source, p-type wide band gap a-SiC:H films have been obtained. The result has been found that the undoped layers of the pin/substrate solar cells are influenced by the residual impurities, such as phosphorus and boron during the deposition process. By minimizing the effect of the impurities in the i-layer and optimizing conditions at the p-layer and p/i interface, the energy conversion efficiency of 9.61 % under AM-1 ($100mW/Cm^2$) has been achieved for pin/substrate solar cells illuminated through their p-layers, using the three separate reaction chamber apparatus. It is expected that a-SiC:H solar cells with the energy conversion efficiency over 10% have been fabricated by Photo-CVD method.

• 동의신경정신과학회지
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• 제21권2호
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• pp.29-44
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• 2010

Objectives : The purpose of this study was to investigate the effect of Gentianae Radix on neurogenesis and apoptosis in ethanol- induced newborn rats hippocampus dentate gyrus. Methods : In vivo, laboratory animals were divided into three groups; Normal group(N), Control group(C) and Treated group (TG)(n=7 for each group). N were treated saline daily for five days. C were treated 1.5 g/kg ethanol and saline daily for five days. TG were treated 1.5 g/kg ethanol and 300 mg/kg Gentianae Radix daily for five days. BrdU(5-bromo-2-deoxyuridine) assay was used to test neurogenesis in the dentate gyrus. And TUNEL(Terminal deoxynucleotidyl transferase dUTP nick end labeling) assay was used to test apoptosis in the dentate gyrus. Three groups were measured body weight, serum ethanol concentration, BrdU-positive cells and TUNEL-positive cells in the dentate gyrus. In vitro, MTT(3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was used to test viability in SK-N-MC cells. BrdU assay was used to test neurogenesis in SK-N-MC cells. DNA fragmentation and caspase-3 enzyme activity assay were used to test apoptosis in SK-N-MC cells. And treated ethanol and Gentianae Radix of all in vitro tests were made various concentration. Results : In vivo, Gentianae Radix modulated ethanol-induced neurogenesis and apoptosis in newborn rats hippocampus dentate gyrus. In vitro, TG 100 ${\mu}g/ml$ have significantly modulated ethanol-induced neurogenesis and apoptosis in SK-N-MC cells. And only TG 100 ${\mu}g/ml$ have significantly protected SK-N-MC cells from ethanol-induced cytotoxicity. Conclusions : Gentianae Radix may have the effect that modulated ethanol-induced neurogenesis and apoptosis in SK-N-MC cells.