• Journal of Microbiology
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• 제40권4호
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• pp.313-318
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• 2002

To perform the prophylactic study of a vaccine derived from human papillomavirus (HPV) using Balb/c mice, we produced virus like particles consisting of HPV capsid protein L1 which has been reported to induce significant humoral and cellular immunity using various animal model systems. In order to produce HPV16 VLPs, the cDNA of L1 capsid protein in HPV type 16, obtained by polymerase chain reaction, was inserted into yeast expression vector, YEG$\alpha$-HIR525 under the control of GAL10 promoter. The transformation of YEG$\alpha$-HPV16 L1 was performed into the yeast Saccharomyces cerevisiae Y2805 by the lithium acetate method and the yeast clone expressing the highest level of L1 capsid protein of human papillomavirus type 16 was selected by Western blot analysis using anti-HPV16 L1 antibody. The purification of HPV16 VLP has been performed by the ultracentrifugation and gel-filtration methods. To validate the vaccine efficacy of the purified HPV16 VLPs and investigate the properties of HPV16 VLPs to induce humoral immunity, ELISA assay was performed. A significantly increased production of anti-HPV16 VLP antibodies was observed in sera from immunized mice. The neutralization activity of antibodies in the sera from the vaccinated mice was demonstrated by a rapid and simple assay to detect hemagglutihation inhibition activity.

• Reproductive and Developmental Biology
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• 제35권3호
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• pp.341-348
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• 2011

Sloan-Kettering virus gene product of a cellular protooncogene c-Ski is an unique nuclear pro-oncoprotein and belongs to the Ski/Sno proto-oncogene family. Ski plays multiple roles in a variety of cell types, it can induce both oncogenic transformation and terminal muscle differentiation when expressed at high levels. The aim of the present study was to locate Ski protein in rat ovaries in order to predict the possible involvement of Ski in follicular development and atresia. First, expression of c-Ski mRNA in the ovaries of adult female rats was confirmed by RT-PCR. Then, ovaries obtained on the day of estrus were subjected to immunohistochemical analysis for Ski and proliferating cell nuclear antigen (PCNA) in combination with terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). Ski was expressed in granulosa cells that were positive for TUNEL, but negative for PCNA, regardless of the shape and size of follicles. Expression of Ski in TUNEL-positive granulosa cells, but not in PCNA-positive granulosa cells, was also verified in immature hypophysectomized rats having a single generation of developing and atretic follicles by treatment with equine chorionic gonadotropin (eCG). These results indicate that Ski is profoundly expressed in the granulosa cells of atretic follicles, but not in growing follicles, and suggest that Ski plays a role in apoptosis of granulosa cells during follicular atresia.

• 대한미생물학회지
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• 제17권1호
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• pp.7-14
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• 1982

A model of induction of neoplasia by viruses has develpoed from experimental studies in animals and in cultured cells and oncogenic transformation of cells is the result of integration of viral genetic information into the cellular DNA. The evidence for these associations was derived primarily from seroepidemiologic investigation. However, data indicating that the relation between HSV-2 and cervical cancer fits the model derived from experimental animal studies are not yet sufficient to draw conclusion with regard to the etiologic role the virus in the development of the neoplasms. In other hand, the K562 tumor cell is highly susceptible target for natural killer cell lysis by the lymphocytes of human and murine periperal blood. The characteristics of this effector cell type has been investigated. A study on natural killer cell mediated cytotoxicity(NKMC) against $^{51}Cr$-K562 as target cell was studed in HSV-2 infected ICR mouse. We have studied for susceptibility of HSV-2 against mouse embryo fibroblast(MEF) cells and NKMC from HSV-2 infected mouse. The results obtained that the mouse embryo fibroblast cells culture, the number and size of the cells were markedly increased and formed a monolayers relatively rapid, and become complete monolayer sheet around 72 hrs. Duration of cytopathic effect on MEF cells was rapid by serial passing of HSV-2. The morphology of the HSV-2 infected cells appear to be mainly round, ovium, spindle form and some of them was forming large giant cells. The NKMC was decrease in mouse with HSV-2 and comparison between effector/target cells ratio as 25:1 and 50:1 respectively, the NKMC was found to be more significantly decreased than normal control we have concluded that the natural killer cell activity of the viral infected mouse was shown as a suppressed during the HSV-2 infection, day 7th and 14th.

• 한국정보통신학회논문지
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• 제14권6호
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• pp.1469-1475
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• 2010

본 논문에서는 기존의 MLCA(Maximum Length CA) 및 여원 MLCA 기반의 난수열을 이용한 영상 암호화 방법의 문제점을 제시하고 이를 해결하기 위한 암호화 방법을 제안한다. 기존의 암호화 방법은 영상에서 인접한 픽셀간의 유사한 색상 값을 가지는 특성으로 인해 암호화된 영상에 원영상의 윤곽이 나타나는 문제점이 발생한다. 본 방법은 MLCA 기반의 난수열을 생성하고, 이를 이용해서 픽셀의 색상 값뿐만 아니라 공간좌표를 무질서하게 변환함으로써 영상을 암호화한다. 이러한 방법은 영상 데이터를 시각화하기 위한 영상의 기본 정보인 픽셀의 색상 값과 공간좌표를 변환시키기 때문에 기존 암호화 방법보다 향상된 암호화 결과를 얻을 수 있다. 히스토그램 및 키 공간 분석을 통해 본 암호화 방법의 안정성을 평가한다.

• BMB Reports
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• 제40권3호
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• pp.341-348
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• 2007

Herpesvirus saimiri (HVS), a member of the $\delta$-herpesvirus family, encodes an oncoprotein called Saimiri Transforming Protein (STP) which is required for lymphoma induction in non-human primates. Previous study has shown that STP-C, an oncoprotein of HVS, activates NF-$\kappa$B signaling pathway. However, the detailed mechanism of STP-Cmediated NF-$\kappa$B activation has not been reported yet. We first report that STP-C interacts with TRAF6 protein in vivo and in vitro and further investigation shows that $Glu_{12}$ residue of STP-C is critical for binding to TRAF6. Introduction of ubiquitin together with STP-C augments NF-$\kappa$B activity compared to that of STP-C expression alone. STP-C expression further induces ubiquitination of endogenous TRAF6. In addition, either a deubiquitination enzyme, CYLD or a dominant negative E2-conjugation enzyme reduced NF-$\kappa$B activity in spite of the presence of STP-C, supporting that the interaction between STP-C and TRAF6 induces ubiquitination of TRAF6. NF-$\kappa$B activation by STP-C through the ubiquitinated TRAF6 causes the increased production of IL-8, an inflammatory chemokine and the enhanced expression of costimulatory molecule ICAM, which might ultimately contribute cellular transformation by the exposure of HVS-infected cells with inflammatory microenvironment and chronic activation.

• Molecular & Cellular Toxicology
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• 제1권2호
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• pp.73-77
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• 2005

Nickel is the one of potent environmental, the occupational pollutants and the classified human carcinogens. It is a serious hazard to human health, when the metal exposure. To prevent human diseases from the heavy metals, it is seemingly important that understanding of how nickel exerts their toxicity and carcinogenic effect at a molecular and a genomic level. The process of nickel absorption has been demonstrated as phagocytosis, iron channel and diffusion. Uptaked nickel has been suggested to induce carcinogenesis via two pathways, a direct DNA damaging pathway and an indirect DNA damaging pathway. The former was originated from the ability of metal to generate Reactive Oxygen Species (ROS) and the reactive intermediates to interact with DNA directly. Ni-generated ROS or Nickel itself, interacts with DNAs and histones to cause DNA damage and chromosomal abnormality. The latter was originated from an indirect DNA damage via inhibition of DNA repair, or condensation and methylation of DNA. Cells have ability to protect from the genotoxic stresses by changing gene expression. Microarray analysis of the cells treated with nickel or nickel compounds, show the specific altered gene expression profile. For example, HIF-I (Hypoxia-Inducible Factor I) and p53 were well known as transcription factors, which are upregulated in response to stress and activated by both soluble and insoluble nickel compounds. The induction of these important transcription factors exert potent selective pressure and leading to cell transformation. Genes of metallothionein and family of heat shock proteins which have been known to play role in protection and damage control, were also induced by nickel treatment. These gene expressions may give us a clue to understand of the carcinogenesis mechanism of nickel. Further discussions on molecular and genomic, are need in order to understand the specific mechanism of nickel toxicity and carcinogenicity.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1305-1310
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• 2012

Breast cancer cells undergo transformation when they spread into surrounding tissues. Studies have shown that cancer cells undergo surface alterations and interact with the surrounding microenvironment during the invasion process. The aim of the present study was to analyse these cancer cell surface alterations and interactions of cancer cells and stroma. Twenty 1-methyl-1-nitrosourea-induced breast cancer samples taken from five rats were fixed in McDowell-Trump fixative and then washed in 0.1 M phosphate buffer. The samples were then treated with osmium tetroxide before being washed in distilled water and subsequently dehydrated through graded ethanols. The dehydrated samples were immersed in hexamethyldisilazane (HMDS), then following removal of excess HMDS, the samples were air dried at room temperature in a dessicator. The dried samples were mounted onto specimen stubs and coated with gold coater before being viewed under a scanning electron microscope. We detected the presence of membrane ruffles on the surface of cancer cells and the formation of unique surface membrane protrusions to enhance movement and adhesion to the surrounding stroma during the process of invasion. Advancing cancer cells demonstrated formation of lamellipodia and invadopodia. The stroma at the advancing edge was desmoplastic with many collagen fibres laid down near the cancer cells. Our data suggest that all of these abnormalities could act as hallmarks of invasiveness for breast cancer.

• Biomolecules & Therapeutics
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• 제7권2호
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• pp.105-111
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• 1999

Nitric oxide (NO), a cellular messenger synthesized from L-arginine by NO synthase (NOS, EC.1.14.13.39), is considered to be a regulator of gastric secretion. In the present study, the role of NO in the regulation of exocrine secretion was investigated in rat gastric chief cells. Treatment of chief cells with carba-chol resulted in an increase in the arginine conversion to citrulline, the amount of $NO_{x}$, the release of pepsine-gen, and the level of cGMP Especially, carbachol-stimulated increase of arginine to citrulline transformation, the amount of $NO_{x}$, cGMP level and the release of pepsinogen were partially reduced by the natural NOS inhibitor, $N^{G}$-monomethyl-L-arginine (MMA) and $N^{G}$, $N^{G}$-dimethyl-L-arginine (DMA). Furthermore, MMA- and DMA-induced decrease of pepsinogen secretion showed dose-dependent patters. Activation of NOS is one of the early events in receptor-mediated cascade of reactions in gastric chief cells and NO, not completely, but partially mediates gastric secretion. Agonist-stimulated pepsinogen secretion in chief cells has been considered to be mediated in adenosine 3',5'-cyclic monophosphate pathway and/or guanosine 3', 5'-cyclic monophosphate (cGMP) pathway. Taken together, the above results suggest that partial decrease of exocrine secretion following treatment of NOS inhibitor may result from the inactivation of NOS and subsequent guano- late cyclase, and NO/cGMP pathway may play a pivotal role in exocrine secretion.

• 한국산학기술학회논문지
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• 제8권3호
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• pp.563-568
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• 2007

본 논문에서는 EVRC 시스템에 사용되어지는 실근 방식의 계산량 감소 알고리즘을 치안한다. 실근 방법에서는 다항식에서의 근을 구하여 LSP로 변환하는 과정이 필요하다. 그러나, 근을 구하는 과정에서 주파수 대역을 순차적으로 검색하므로 계산시간이 많이 소요된다. LSP 파라미터의 중요한 특징은 대부분의 계수가 특정 주파수 대역에 주로 분포한다는 것이다. 그러므로, 본 논문에서는 실근 방식에서의 계산시간을 줄이기 위하여 1KHz 대역까지는 선형적이고 1KHz 대역 이상에서는 로그 스케일인 멜 스케일을 사용하였다. 실근 방식과 제안한 방법을 비교하기 위하여 두 가지를 측정하였다. 첫째, 제안한 방법에서의 LSP 파라미터의 값과 실근방식에서의 LSP 파라미터 값을 비교하였다. 둘째, 계산 시간 감소율을 측정하였다. 실험결과, LSP 파라미터의 값은 변화하지 않았으며 계산량은 약 48% 정도 감소하였다.

• 한국미생물·생명공학회지
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• 제14권3호
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• pp.213-218
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• 1986

B. amyloliquefaciens의 $\alpha$-amylase 유전자가 S. cerevisiae 내에서 형질발현하는 가를 조사하기 위하여 본, 연구에서 YRp7 plasmid에 B. amyloliquefaciens amylase유전자를 cloning하여 만든 pEA24를 형질전환시켰다. 먼저 YRp7 plasmid를 이용하여 형질전환 최적 조건을 검토하여 본 바, PH 7과 8사이, 반응온도 3$0^{\circ}C$에서 40%의 polyethylene glycol(MW 4,000)을 처리한 후 2 %의 agar를 함유한 재생배지에 중층도말 하였을 때 형질전환율이 가장 높았다. 형질전환주로부터 생성된 amylase의 활성을 측정한 결과, S. cerevisiae에서 약간의 amylase활성을 나타내어 최고 B. amyloliquefaciens의 2% 정도였고, 세포외효소는 검출되지 않았다. 이들 형질전환 주가 가지고 있는 pEA24 plasmid의 안정성을 조사한 결과 YRp7보다 불안정하였으며, 추출한 DNA를 전기영동하여 그 band를 확인하였다.