• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.63-63
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• 2003

플라즈마 공정은 DRAM, 이종접합 양극성 트랜지스터(HBTs), 레이저, 평면도파로(planar lightwave circuit)와 같은 전자소자 및 광조자 제작에 있어서 핵심 공정중의 하나이다. 최근 미세 구조의 크기가 극도로 감소하게 됨에 따라 실제 소작 제작에 있어서 미세한 모양을 식각하는 공정이 매우 중요하게 되었다. 그 중에서 고밀도 유도결합 플라즈마(high density inductively coupled plasma)를 이용한 기술은 빠르고 정확한 식각률, 우수한 식각 균일도와 높은 재현성 때문에 습식식각 기술보다 선호되고 있다. 본 연구는 평판형(planar) 고밀도 유도결합 플라즈마 식각장치를 이용하여 BCl$_3$와 BCl$_3$/Ar 플라즈마에 따른 AlGaAs/GaAs의 식각결과를 비교 분석하였다. 공정 변수는 ICP 소스(source power)파워, RIE 척(chuck) 파워, 공정 압력, 그리고 Ar 조성비(0-100%)이었다. BCl$_3$에 Ar을 첨가하게 되면 순수한 BCl$_3$ 플라즈마에서의 AlGaAs/GaAs 식각률(> 3000 $\AA$/min) 보다 분당 약 1000$\AA$ 이상 높은 식각률(>4000 $\AA$/min)을 나타내었다. 이 결과는 Ar 플라즈마의 이온보조(ion-assisted)가 식각률 증가에 기인한다고 예측된다. 그리고 전자주사 현미경(SEM)과 원자력간 현미경(AFM)을 사용하여 식각 후 표면 거칠기 및 수직 측벽도 둥을 분석하였다. 마지막으로 XPS를 이용하여 식각된 후에 표면에 남아 있는 잔류 성분 분석을 연구하였다. 본 결과를 종합하면 BCl$_3$에 기초한 평판형 유도결합 플라즈마는 AlGaAs/GaAs 구조의 식각시 많은 우수한 특성을 보여주었다.79$\ell/\textrm{cm}^3$, 0.016$\ell/\textrm{cm}^3$, 혼합재료 2는 0.045$\ell/\textrm{cm}^3$, 0.014$\ell/\textrm{cm}^3$, 혼합재료 3은 0.123$\ell/\textrm{cm}^3$, 0.017$\ell/\textrm{cm}^3$, 혼합재료 4는 0.055$\ell/\textrm{cm}^3$, 0.016$\ell/\textrm{cm}^3$, 혼합재료 5는 0.031$\ell/\textrm{cm}^3$, 0.015$\ell/\textrm{cm}^3$, 혼합재료 6은 0.111$\ell/\textrm{cm}^3$, 0.020$\ell/\textrm{cm}^3$로 나타났다. 3. 단일재료의 악취흡착성능 실험결과 암모니아는 코코넛, 소나무수피, 왕겨에서 흡착능력이 우수하게 나타났으며, 황화수소는 펄라이트, 왕겨, 소나무수피에서 다른 재료에 비하여 상대적으로 우수한 것으로 나타났으며, 혼합충진재는 암모니아의 경우 코코넛과 펄라이트의 비율이 70%:30%인 혼합재료 3번과 소나무수피와 펄라이트의 비율이 70%:30%인 혼합재료 6번에서 다른 혼합재료에 비하여 우수한 것으로 나타났으며, 황화수소의 경우 혼합재료에 따라 약간의 차이를 보였다. 4. 코코넛과 소나무수피의 경우 암모니아가스에 대한 흡착성능은 거의 비슷한 것으로 사료되며, 코코넛의 경우 전량을 수입에 의존하고 있다는 점에서 국내 조달이 용이하며, 구입 비용도 적게 소요되는 소나무수피를 사용하는 것이 경제적이라고 사료된다. 5. 마지막으로 악취제거 미생물균주를 접종한 소나무수피 70%와 펄라이트 30%의 혼합재료를 24시간동안 장기간 운전

• Journal of Life Science
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• v.14 no.3
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• pp.445-452
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• 2004

We investigated the cytotoxic effects of seven furanoterpenoids 〔sarcotin A, epi-sarcotin A, ircinin-1, epi-sarcotrine B, sarcotin I, (8E, l3Z, 20Z)-strobilinin/(7E,l3Z, 20Z)-felixinin and (7E,12E,18R,20Z)-variabilin〕 isolated from the sponge Sarcotragus sp. (the order Dictyoceratida) on the growth of A549 human lung carcinoma cells. MTT data revealed that sarcotin A and (7E,12E,18R,20Z)-variabilin exhibited higher potencies on the anti-proliferative activities than the other compounds in A549 cells. The growth inhibition by treatment with compounds (especially epi-sarcotin A, ircinin-1 and epi-sarcotrine B) were associated with the induction of apoptotic cell death through the concentration-dependent increase of Bax/Bcl-2 ratio in a p53-dependent or independent pathway Additionally, epi-sarcotin A and ircinin-1 strongly inhibited the levels of cyclooxygenase (COX)-2 expression without alteration of COX-1. Taken together, the results suggest that the furanoterpenoids from the marine sponge have strong potentials as candidates for anti-cancer drugs.

• Development and Reproduction
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• v.15 no.2
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• pp.159-166
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• 2011

Simazine (6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine) is a triazine herbicide that has been applied worldwide including Korea for agricultural purposes. Simazine is the second most commonly detected pesticide in surfaceand ground-water in the United States, Europe and Australia. It has been shown that simazine is a potent endocrine disruptor in wildlife and laboratory animals. Although many endocrine disruptors can induce apoptosis in various types of cells, the effects of simazine on apoptosis and on the expression of Bcl-2 family genes are not known. Also it is unknown the effect of simazine on the expression of steroidogenesis-regulating genes in testicular cells. In this study, we investigated the effect of simazine on the expression levels of apoptosis- and steroidogenesis-regulating genes in testicular cells. We found that a low concentration of simazine can alter the mRNA expression levels of steroidogenesis-related genes and Bcl-2 family genes in mouse Sertoli cells and rat Leydig cells. Thus, our results suggest that simazine can disturb normal testicular development and reproductive function by altering the expression of genes that are critical for the regulation of apoptosis and steroidogenesis.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.4
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• pp.13-22
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• 2011

Objectives : This Study was performed to evaluate the effects of Scutellariae Radix(SR) water-extract on the tissue and neuronal apoptosis of the spinal cord injury(SCI). Methods: SCI was induced by mechanical contusion following laminectomy of 10th thoracic vertebra in Sprague-Dawley rats. SR was orally given once a day for 7 days after SCI. Neuronal apoptosis was examined with terminal deoxynucleotidyl transferase-mediated dUTPnick-end labeling(TUNEL) assay. Bax (Bcl-2-asociated X protein), Bcl-2(B-cell blastoma 2), c-Fos(FBJ osteosarcoma oncogene) expressions were examined using immuno-histochemistry. Individual TUNEL and immuno-labeled cells expressing Bax, Bcl-2 and c-Fos were counted on the same level in peri-damaged region and in ventral horn. Results: 1. SR significantly reduced number of TUNEL labeled apoptotic cells induced by the spinal cord contusion injury. 2. SR significantly reduced Bax positive cells expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. 3. SR strengthened Bcl-2 expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. 4. SR reduced c-Fos expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. Conclusions : These results suggest that SR plays an inhibitory role against neuronal apoptosis and has significant effects for locomotor disfunction induced by SCI.

• Nutrition Research and Practice
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• v.12 no.6
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• pp.494-502
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• 2018

BACKGROUND/OBJECTIVES: Reducing the number of adipocytes by inducing apoptosis of mature adipocytes as well as suppressing differentiation of preadipocytes plays an important role in preventing obesity. This study examines the anti-adipogenic and pro-apoptotic effect of red pepper seed water extract (RPS) prepared at $4^{\circ}C$ (RPS4) in 3T3-L1 cells. MATERIALS/METHODS: Effect of RPS4 or its fractions on lipid accumulation was determined in 3T3-L1 cells using oil red O (ORO) staining. The expressions of AMP-activated protein kinase (AMPK) and adipogenic associated proteins [peroxisome proliferator-activated receptor-${\gamma}$ ($PPAR-{\gamma}$), CCAAT/enhancer-binding proteins ${\alpha}$ (C/EBP ${\alpha}$), sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC)] were measured in 3T3-L1 cells treated with RPS4. Apoptosis and the expression of Akt and Bcl-2 family proteins [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad), Bcl-2 like protein 4 (Bax), Bal-2 homologous antagonist/killer (Bak)] were measured in mature 3T3-L1 cells treated with RPS4. RESULTS: Treatment of RPS4 ($0-75{\mu}g/mL$) or its fractions ($0-50{\mu}g/mL$) for 24 h did not have an apparent cytotoxicity on pre and mature 3T3-L1 cells. RPS4 significantly suppressed differentiation and cellular lipid accumulation by increasing the phosphorylation of AMPK and reducing the expression of $PPAR-{\gamma}$, C/EBP ${\alpha}$, SREBP-1c, FAS, and ACC. In addition, all fractions except ethyl acetate fraction significantly suppressed cellular lipid accumulation. RPS4 induced the apoptosis of mature adipocytes by hypophosphorylating Akt, increasing the expression of the pro-apoptotic proteins, Bak, Bax, and Bad, and reducing the expression of the anti-apoptotic proteins, Bcl-2 and p-Bad. CONCLUSIONS: These finding suggest that RPS4 can reduce the numbers as well as the size of adipocytes and might useful for preventing and treating obesity.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1337-1347
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• 2009

Purpose:Taurine (2-aminoethanesulfonic acid) is a simple sulfur-containing amino acid. It is abundantly present in tissues such as brain, retina, heart, and skeletal muscles. Current studies have demonstrated the neuroprotective effects of taurine, but limited data are available for such effects during neonatal period. The aim of this study was to determine whether taurine could reduce hypoxic-ischemic (HI) cerebral injury via anti-apoptosis mechanism. Methods:Embryonic cortical neurons isolated from Sprague-Dawley (SD) rats at 18 days gestation were cultured in vitro. The cells were divided into hypoxia group, taurine-treated group before hypoxic insult, and taurine-treated group after HI insult. In the in vivo model, left carotid artery ligation was performed in 7-day-old SD rat pups. The pups were exposed to hypoxia, administered an injection of 30 mg/kg of taurine, and killed at 1 day, 3 days, 1 week, 2 weeks, and 4 weeks after the hypoxic insult. We compared the expressions of Bcl-2, Bax, and caspase-3 among the 3 groups by using real- time polymerase chain reaction (PCR) and western blotting. Results:The cells in the taurine-treated group before hypoxic insult, although similar in appearance to those in the normoxia group, were lesser in number. In the taurine-treated group, Bcl-2 expression increased, whereas Bax and caspase-3 expressions reduced. Conclusion:Taurine exerts neuroprotective effects onperinatal HI brain injury due to its anti-apoptotic effect. The neuroprotective effect was maximal at 1-2 weeks after the hypoxic injury.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.1
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• pp.47-55
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• 2003

Objectives: Bok, Bcl-2-related ovarian killer, is a proapoptotic Bcl-2 family protein identified in the ovary based on its dimerization with the antiapoptotic protein Mcl-1. The present study examined the hormonal regulation and localization of Bok messenger RNA levels in the mouse ovary during the follicle development. Methods: The animals were implanted subcutaneously with Silastic brand capsules containing the synthetic estrogen, DES at $21{\sim}23$ days of age. Ovaries were collected $1{\sim}3$ days after implantation for RNA analysis and in situ hybridization. Some mice were removed capsule for $1{\sim}2$ days to induce ovarian follicle apoptosis. Ovaries were also collected from 26 day-old immature mice at various times after treatment with 10 IU PMSG. Some mice received a single intraperitoneal injection of 10 IU hCG to induce ovulation, and ovaries were obtained at different time intervals for Northern blot and in situ hybridization analysis, respectively. Results: Treatment of immature mice with diethylstilbestrol (DES) for $24{\sim}48$ h increased ovarian Bok mRNA levels. Bok mRNA was remained the same levels in mice removed DES for $24{\sim}48$ h to induce apoptosis. High signals of Bok mRNA after DES treatment were detected in granulosa cells of early antral follicles. Treatment of immature mice with PMSG for 12 h increased markedly ovarian Bok mRNA expression which was detected mainly in preantral and atretic follicles. Interestingly, low levels of Bok mRNA were also expressed in granulosa cells of preovulatory follicles. Treatment of PMSGprimed mice with hCG stimulated strongly ovarian Bok mRNA expression at $6{\sim}9$ h. At that time, Bok mRNA was expressed in granulosa cells of atretic and small growing follicles. Conclusion: These results demonstrate that Bok is one of proapoptotic Bcl-2 members expressed in early growing and atretic follicles during the ovarian follicular development. Gonadotropins induce a transient increase of Bok gene expression in granulosa cells of preantral and preovulatory follicles indicating some role in the ovulatory process.

• Development and Reproduction
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• v.14 no.2
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• pp.83-89
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• 2010

Apoptosis is a crucial mechanism for the proper regulation of homeostasis. BCL-2 family proteins are key molecules which control cellular survival and apoptosis. MCL-1 (myeloid cell leukemia-1) is a pro-survival member of BCL-2 family that promotes the survival of cells, and is highly expressed in diverse cancers including ovarian cancer, leukemia, and cervical cancer. Previously we identified IEX-1 (immediate early response gene X-1) as a binding partner of MCL-1. In the present study, we demonstrated that overexpression of IEX-1 induced apoptosis of ovarian cancer cells. Moreover, IEX-1 significantly attenuated the pro-survival function of MCL-1 in these cells. Also, IEX-1-induced cell death activity was able to be modulated by changes in the expression level of MCL-1. Thus, these results suggest that both IEX-1 and MCL-1 modulate each other's function controlling cellular survival and death and the inhibitory activity of IEX-1 toward MCL-1 may be applied for the development of chemotherapeutics.

• The Journal of Internal Korean Medicine
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• v.27 no.2
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• pp.379-393
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• 2006

Objectives: We are aimed to identify anti-tumor effects of Curcuma aromatics on some kinds of cancer cells through molecular biologic methods. Materials & Methods: We used 4 kinds of cancer cell lines such as lung cancer cells(AS49), cervical cancer cells(HeLa), glioma cancer cells(A172) and prostate cancer cells(PC3). We treated the boiled extract of Curcuma aromatica $5{\mu}g,\;10{\mu}g$ to cultural media(ml) for 24 hours. We measured the cytotoxicitv on 4 kinds of cancer cells through tryphan blue exclusion test and the suppressive effect on viability of 4 kinds of cancer cells via MTT assay. We measured change of mitochondria membrane potential via flow cytometry. The quantitative RT-PCR was used to examine the effect on the revelation of Bcl-2 and Bax which are genes related to apoptosis. We examined the effect on the revelation of Bcl-2 Protein and Bar protein by western blot analysis. Results : In the experiment of tryphan blue exclusion test, the extract of Curcuma aromatica showed more significant killing effect on AS49, HeLa than the control group with density dependent manner, which was statistically significant. In the experiment of MTT assay the extract of Curcuma aromatica showed more suppressive effect on viability of A549, HeLa than the control group with density dependent manner, which was statistically significant. Curcuma aromatica induced apoptosis by decreasing the membrane potential of mitochondria in A549, HeLa. In the experiment of the revelation of genes related to apoptosis, the revelation of Bcl-2 decreased and the revelation of Bax increased in A549, HeLa treated with Curcuma aromatica with dose dependent manner. In the experiment of the revelation of protein related to apoptosis, the protein levels of Bcl-2 decreased and the protein levels of Bax increased in AS49, HeLa treated with Curcuma aromatica with dose dependent manner. Conclusions: From this study, we can infer that Curcuma aromatica has anti-tumor effect on lung cancer cells and uterine carcinoma cells but not on glioma cells and prostate cancer cells.

• Korean Journal of Head & Neck Oncology
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• v.21 no.2
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• pp.146-150
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• 2005

Background and Objectives: When the pleomorphic adenoma(PA) recures, the tumor tends to become a multinodular mass that infiltrates into the normal tissue which is not a common condition for a benign tumor. This manifestation is probably due to the difference in cell biology of the recurrent tumor compared to that of the primary PA. The aim of this study is to assay the immunhistochemical characteristics of the recurrent PA compared to the primary PA and to evaluate whether this property can be used for developing a method that can select the patients who have higher risk to recur. Materials and Methods: Thirteen patients were enrolled in the primary PA group and 15 patients who had a recurrent PA were enrolled in the recurrent PA group. To evaluate the cell biology of the tumor, immunohistochemical stainings of Ki-67, bcl-2 and p53 were performed. Results: There was no difference in the expression of Ki-67 (p=0.117, p=.208) and p53 (p=.430, p=.328). The extent stained by bcl-2 was significantly larger in the recurrent PA group (p=.033, p=.014). The expression of bcl-2 did not increase while time passed. Conclusion: The high expression of bcl-2 seems to be a property of the recurrent PA group which can be found even during first operation before recurrence. By this immunhistochemical characteristic, we would be able to sort out the patients who have higher risk to recur.