• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.597-606
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• 2008

Resorption of alveolar bone in periodontitis is due to excessive differentiation and activation of osteoclasts. Bacterial antigens causing periodontitis activates CD4 T cells, which leads to expressing RANK ligand (RANKL) on CD4 T cells. RANKL binds RANK on preosteoclasts or osteoclasts, and enhances the differentiation preosteoclasts into osteoclasts and the activation of mature osteoclasts. CD137, one of TNF receptor (TNFR) family, expressed on activated T cells binds with CD137 ligand (CD137L) on antigen presenting cells. Cross-linking of CD137 by CD137L acts as T cell co-stimulatory signals and, therefore, enhances the activation of T cell. In this study, I elucidated the biological responses of CD137L on (pre)osteoclasts and RANKL on T cells in the context of in vivo interaction between T cells and osteoclasts. RAW264.7, murine monocytic cells, constitutively express CD137L. Ligation of CD137L with anti-CD137L mAb inhibited RANKL-induced osteoclast formation in a dosedependent manner. Bone marrow cells are expressed CD137L by the treatment with M-CSF. Cross-linking of CD137L abolished M-CSF/ RANKL-evoked the formation of multi-nucleated osteoclasts. Both mouse CD4 and CD8 T cells are expressed RANKL following their activation. Ligation of RANKL with OPG, the decoy receptor for RANKL, inhibited both CD4 and CD8 T cell proliferation. These effects were attributed to RANKL-induced apoptosis. These data indicate that CD137L and RANKL on osteoclasts and T cells, respectively provide them with inhibitory signal.

• Cross-Cultural Studies
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• v.44
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• pp.123-145
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• 2016

A flow of generative change has existed in the Chinese media following political, economic, and institutional changes. Since a market system was introduced to the field of drama production, people called 'zhipianren' who act as government agents as well as market administrators have spontaneously emerged. The government, by granting legal qualifications and authority to these 'zhipianren', have institutionalized and absorbed them within the system. Through this process, the 'drama zhipianren system', under the unique environment of a socialist market economy, demonstrates a Chinese administrative model that effectively reveals the changing process from a direct administration by the government to indirect administration and self-censorship. Furthermore, with the widespread adoption of the internet, various types of media including grassroots media have emerged, and the participation and production activities of netizens has enabled the development of a new genre of literature called internet literature. Furthermore, some websites that functioned as platforms for video and grassroots media came to self-produce contents so as to function as media in and of themselves. Originally, the internet was cultivated as a portion of the IT industry, but when it began to function as media, forming a new media landscape, regulations and institutions were gradually established and subsequently advanced in the direction of supervision and regulation over all internet media contents. A flow of generative change in the field of media has emerged, and the pattern of generation-convergence repeats itself as the official media policies converge.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.812-817
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• 2011

Rolling stocks are often subjected to the effects of natural cross wind or train wind pressure due to the crossing train. These wind pressure cause the falling-off in running stability and turnover problem. It is sometimes reported that trains are blown over by a gust of wind in overseas. So, many countries enact regulations to secure the safety for wind speed. In this study, we analyzed the difference between the regulation for turnover safety of train which was enacted by Ministry of Land. Transport and Maritime Affairs and that based on the multi-body model. In case of multi-body model, it is assumed that the degrees of freedom for carbody and bogie are assigned an independent values respectively. The results show that the latter approach based on multi-body model can access the safety of turnover and replace the computational method which is accessing with lateral force, derailment coefficient and decrement of wheel load.

• BMB Reports
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• v.45 no.3
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• pp.159-164
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• 2012

CD99 is known to be involved in the regulation of cell-cell adhesion. However, it remains unclear whether CD99 controls cell-extracellular matrix adhesion. In this study, the effects of CD99 activation on cell-extracellular matrix adhesion were investigated. It was found that engagement of CD99 with the stimulating antibody YG32 downregulated the adhesion of MCF-7 cells to fibronectin, laminin and collagen IV in a dose-dependent manner. The CD99 effect on cell-ECM adhesion was inhibited by overexpression of the dominant negative form of CD99 or CD99 siRNA transfection. Treatment of cells with $Mn^{2+}$ or by ${\beta}_1$ integrin-stimulating antibody restored the inhibitory effect of CD99 on cell-ECM adhesion. Cross-linking CD99 inactivated ${\beta}_1$ integrin through conformational change. CD99 activation caused dephosphorylation at Tyr-397 in FAK, which was restored by the ${\beta}_1$ stimulating antibody. Taken together, these results provide the first evidence that CD99 inhibits cell-extracellular matrix adhesion by suppressing ${\beta}_1$ integrin affinity.

• Journal of Energy Engineering
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• v.5 no.2
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• pp.93-107
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• 1996

Six countries are considered in the study for the comparison of their respective gas industries with the Korean gas industry: the U.S., Canada, the U.K., France, Germany and Japan. The emphases of comparison are given on the cross-evaluation of industry organizations and related regulations. In terms of industrial development stages, the Korean gas industry, with its short experience and in need of more infrastructure, is still young and at an early stage of development. Due to this reason, the study finds that it is premature for the Korean case to propose some policies like the promotion of competition in the gas transportation through third-party access to pipelines. or seeking overseas business opportunities requiring venture capital and advanced technology. Recommendations are made that Korea rather, for the time being, concentrate its energy on the construction of infrastructure and on securing supply sources and diversifying import origins, in order to strengthen it's supply capability in the face of rapidly increasing gas demand in the nation. Nevertheless, Korea will soon have to consider more seriously about the deregulation of the market and more diversified business activities through the development of high technology and managerial skills.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.2
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• pp.1-13
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• 1990

In recent years, the construction of golf course has been increasing very rapidIy and serious concern is paid to its environmental consequences both in Korea and in Japan. EIA systems as a major requirements for golf course developments emerged to reduce the adverse impact of their developments in Korea as well as in Japan. This study aims to compare EIA systems, procedures and methodologies employed between Korea and Japan in order to demonstrate the success and failure of EIAs in each country. The results of this study can be summarized as follows : 1) EIAs are systematically undertaken based upon law in Korea but on regulation in Japan. 2) Public participation Isn't encouraged in the Korean EIA procedure while the Japan EIA system involves public participation. 3) Korean EISs shall be prepared after the proposed projects are approved according to the related laws and be followed by the necessary procedures, but in the carte of Japan, EISs be prepared prior to their approval . 4) ELSs shall be prepared by agencies with special expertise with respect to 7he environmental impacts (appointed by government) or the sponsoring agencies themselves in Korea whereas they be prepared by agencies proposing the projects in japan. 5) EISs both in Korea and in Japan are characterized by cliches which may be unfamiliar to reviews and the public. 6) EIAs describe the existing presence and predict and evaluate that a development work influences the present conditions. Here Japan EIA treats mainly natural - and life environment, whereas Korean EIA dose social - and economic environment. And hence in the case of Japan is undertaken more quantitative and scientific analysis, whereas in the case of Korea is less. It is suggested that the key point to impact analysis is to use the correct concepts, fomulate the comparative studies of methodologies and find the methods that suit the decision as well as which country's own circumstances.

• Nutrition Research and Practice
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• v.8 no.2
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• pp.132-137
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• 2014

BACKGROUND/OBJECTIVES: In this study, the apoptogenic activity and mechanisms of cell death induced by hexane extract of aged black garlic (HEABG) were investigated in human leukemic U937 cells. MATERIALS/METHODS: Cytotoxicity was evaluated by MTT (3-(4, 5-dimethyl-thiazol-2-yl)-2, 5-diphenyl tetrazoliumbromide) assay. Apoptosis was detected using 4,6-diamidino-2-phenyllindile (DAPI) staining, agarose gel electrophoresis and flow cytometry. The protein levels were determined by Western blot analysis. Caspase activity was measured using a colorimetric assay. RESULTS: Exposure to HEABG was found to result in a concentration- and time-dependent growth inhibition by induction of apoptosis, which was associated with an up-regulation of death receptor 4 and Fas legend, and an increase in the ratio of Bax/Bcl-2 protein expression. Apoptosis-inducing concentrations of HEABG induced the activation of caspase-9, an initiator caspase of the mitochodrial mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of poly(ADP-ribose)-polymerase. HEABG also induced apoptosis via a death receptor mediated extrinsic pathway by caspase-8 activation, resulting in the truncation of Bid, and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. However, pre-treatment of U937 cells with the caspase-3 inhibitor, z-DEVD-fmk, significantly blocked the HEABG-induced apoptosis of these cells, and increased the survival rate of HEABG-treated cells, confirming that HEABG-induced apoptosis is mediated through activation of caspase cascade. CONCLUSIONS: Based on the overall results, we suggest that HEABG reduces leukemic cell growth by inducing caspase-dependent apoptosis through both intrinsic and extrinsic pathways, implying its potential therapeutic value in the treatment of leukemia.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.703-712
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• 2016

Monoclonal antibodies with specific antigens have been widely used as targeted therapy for cancer. Hep88 mAb is a monoclonal antibody which shows specific binding with anti-cancer effects against the HepG2 cell line. However, its mechanisms of action are still not completely understood. We examined cell cycling and apoptosis by flow cytometry and mRNA expression of factors involved in apoptosis and paraptosis in Hep88 mAb-treated HepG2 cells by real-time PCR. The cell-cycle analysis demonstrated that growth-inhibitory activity was associated with G2/M cell cycle arrest. Hep88 mAb induced a significant increase in apoptotic cell populations in a dose- and time-dependent manner. The mRNA expression results also suggested that the process triggered by Hep88 mAb involved up-regulation of tumor suppressor p53, pro-apoptotic Bax, Cathepsin B, Caspase-3 and Caspase-9, with a decrease of anti-apoptotic Bcl-2 - thus confirming paraptosis and apoptosis programmed cell death. These findings represent new insights into the molecular mechanisms underlying the anti-cancer properties of Hep88 mAb in liver cancer cells.

• IMMUNE NETWORK
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• v.5 no.3
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• pp.150-156
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• 2005

Background: Dendritic cells (DCs) playa critical role not only in the initiation of immune responses, but also in the induction of immune tolerance. In an effort to regulate immune responses through the modulation of antigen presenting cell (APC) function of DCs, we searched for and characterized APC function modulators from natural products. Methods: DCs were cultured in the presence of propolis components, WP and CP, and then examined for their ability to present exogenous antigen in association with major histocompatibility complexes (MHC). Results: WP and CP inhibited class I MHC-restricted presentation of exogenous antigen (cross-presentation) in a DC cell line, DC2.4 cells, and DCs generated from bone marrow cells with GM-CSF and IL-4. The inhibitory activity of WP and CP appeared to be due not only to inhibition of phagocytic activity of DCs, but also to suppression of expression of MHC molecules on DCs. We also examined the effects of WP and CP on T cells. Interestingly, WP and CP increased IL-2 production from T cells. Conclusion: These results demonstrate that WP and CP inhibit MHC-restricted presentation of exogenous antigen through down-regulation of phagocytic activity and suppression of expression of MHC molecules on DCs.

• Genomics & Informatics
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• v.3 no.1
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• pp.15-23
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• 2005

Background MicroRNAs (miRNAs) are a class of noncoding RNAs found in various organisms such as plants and mammals. However, most of the mRNAs regulated by miRNAs are unknown. Furthermore, miRNA targets in genomes cannot be identified by standard sequence comparison since their complementarity to the target sequence is imperfect in general. In this paper, we propose a kernel-based method for the efficient prediction of miRNA targets. To help in distinguishing the false positives from potentially valid targets, we elucidate the features common in experimentally confirmed targets. Results The performance of our prediction method was evaluated by five-fold cross-validation. Our method showed 0.64 and 0.98 in sensitivity and in specificity, respectively. Also, the proposed method reduced the number of false positives by half compared with TargetScan. We investigated the effect of feature sets on the classification of miRNA targets. Finally, we predicted miRNA targets for several miRNAs in the Caenorhabditis elegans (C. elegans) 3' untranslated region (3' UTR) database. Condusions The targets predicted by the suggested method will help in validating more miRNA targets and ultimately in revealing the role of small RNAs in the regulation of genomes. Our algorithm for miRNA target site detection will be able to be improved by additional experimental­knowledge. Also, the increase of the number of confirmed targets is expected to reveal general structural features that can be used to improve their detection.