• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.123-124
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• 2005

• Food Science and Industry
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• v.48 no.1
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• pp.62-68
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• 2015

• Journal of Dairy Science and Biotechnology
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• v.26 no.1
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• pp.43-51
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• 2008

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.175-182
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• 2005

Abstract Salmonella pathogenicity island 1 (SPI1) gene expression is regulated by many environmental signals such as oxygen, osmolarity, and pH. Here, we examined changes in the expression level of various regulatory proteins encoded within SPI1 in response to three different concentrations of NaCl, using primer extension analysis. Transcription of all the regulatory genes tested was activated most when Salmonella were grown in Luria Broth (LB) containing 0.17 M NaCl. The expression of hilA, invF, and hilD was decreased in the presence of 0.47 M NaCl or in the absence of NaCl, while hilC expression was almost constant regardless of the NaCl concentration when Salmonella were grown to exponential phase under low-oxygen condition. The reduced expression of hilA, invF, and hilD resulted in lower invasion of hilC mutant to the cultured animal cells when the mutant was grown in the presence of 0.47 M NaCl or in the absence of NaCl prior to infection. Among the proteins secreted via the SPI1-type III secretion system (TTSS), the level of sopE2 expression was not influenced by medium osmolarity. Various effects of osmolarity on virulence gene regulation observed in this study is one example of multiple regulatory pathways used by Salmonella to cause infection.

• Genomics & Informatics
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• v.12 no.4
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• pp.181-186
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• 2014

Genome-wide association studies have proven the highly polygenic architecture of complex diseases or traits; therefore, single-locus-based methods are usually unable to detect all involved loci, especially when individual loci exert small effects. Moreover, the majority of associated single-nucleotide polymorphisms resides in non-coding regions, making it difficult to understand their phenotypic contribution. In this work, we studied epistatic interactions associated with three common diseases using Korea Association Resource (KARE) data: type 2 diabetes mellitus (DM), hypertension (HT), and coronary artery disease (CAD). We showed that epistatic single-nucleotide polymorphisms (SNPs) were enriched in enhancers, as well as in DNase I footprints (the Encyclopedia of DNA Elements [ENCODE] Project Consortium 2012), which suggested that the disruption of the regulatory regions where transcription factors bind may be involved in the disease mechanism. Accordingly, to identify the genes affected by the SNPs, we employed whole-genome multiple-cell-type enhancer data which discovered using DNase I profiles and Cap Analysis Gene Expression (CAGE). Assigned genes were significantly enriched in known disease associated gene sets, which were explored based on the literature, suggesting that this approach is useful for detecting relevant affected genes. In our knowledge-based epistatic network, the three diseases share many associated genes and are also closely related with each other through many epistatic interactions. These findings elucidate the genetic basis of the close relationship between DM, HT, and CAD.

• IMMUNE NETWORK
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• v.13 no.1
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• pp.25-29
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• 2013

Ribavirin is an antiviral drug used in combination with pegylated interferon-${\alpha}$ (IFN-${\alpha}$) for the treatment of hepatitis C virus (HCV) infection. Recently, ribavirin was reported to inhibit the suppressive activity of regulatory T (Treg) cells. In the present study, we re-evaluated the effect of ribavirin on $CD4^+$ $CD4^+$ $CD25^+$ Treg cells from normal donors. First, we examined the expression of CTLA-4 and CD39, which are known to play a role in the suppressive function of Treg cells. We found that ribavirin treatment did not modulate the expression of CTLA-4 and CD39 in Treg cells. We also studied the effect of ribavirin on Treg cells in the presence of IFN-${\alpha}$; however, the expression of CTLA-4 and CD39 in Treg cells was not changed by ribavirin in the presence of IFN-${\alpha}$. Next, we directly evaluated the effect of ribavirin on the suppressive activity of Treg cells in the standard Treg suppression assay, by co-culturing CFSE-labeled non-Treg $CD4^+$ T cells with purified Treg cells. We found that ribavirin did not attenuate the suppressive activity of Treg cells. Taken together, while ribavirin reversed Treg cell-mediated suppression of effector T cells in the previous study, we herein demonstrate that ribavirin does not impair the suppressive activity of Treg cells.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.305-314
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• 2018

'New Breeding Techniques (NBTs)' have been one of hot issues, since their future will be affected profoundly by national as well as international regulatory landscapes. In this review, we compare characteristics of NBTs with conventional and genetic modification, and analyze genetically modified organism (GMO) regulatory systems in the context of possible regulation of NBTs. NBTs are very heterogeneous in terms of principles, methodologies, and final products. As Living Modified Organisms (LMO) is defined in the Cartagena Protocol on Biosafety (CPB) as an organism containing novel combination of genetic materials obtained by the use of modern biotechnology, CPB as well as other national legislations locate itself somewhere in the middle between product-based and process-based regulations. It is also noted that jurisdictions with regulatory systems more oriented to product-based one tend to be more productive and decide or may decide to exempt site-directed nucleases-1 from GMO regulation. In this context, Korean legislations are reviewed to clarify the commons and differences in GMO definitions. Act on Transboundary Movement of LMO Act, Food Sanitation Act and Agricultural and Fishery Products Quality Control Act are three major acts to regulate GMOs. It is noted that there are differences in the definition of LMO or GM food/products especially between the LMO Act and the Food Sanitation Act. Such differences may cause conflicts between Acts when policy-decision regarding the regulation of NBTs is made. Therefore, it is necessary to reorganize legislations before policies regarding the regulation of any techniques from biotechnology are made.

• Hanyang Medical Reviews
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• v.33 no.1
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• pp.10-16
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• 2013

Follicular helper T cells (Tfh) play a significant role in providing T cell help to B cells during the germinal center reaction, where somatic hypermutation, affinity maturation, isotype class switching, and the differentiation of memory B cells and long-lived plasma cells occur. Antigen-specific T cells with IL-6 and IL-21 upregulate CXCR5, which is required for the migration of T cells into B cell follicles, where these T cells mature into Tfh. The surface markers including PD-1, ICOS, and CD40L play a significant role in providing T cell help to B cells. The upregulation of transcription factor Bcl-6 induces the expression of CXCR5, which is an important factor for Tfh differentiation, by inhibiting the expression of other lineage-specific transcription factors such as T-bet, GATA3, and RORγt. Surprisingly, recent evidence suggests that CD4 T cells already committed to Th1, Th2, and Th17 cells obtain flexibility in their differentiation programs by downregulating T-bet, GATA3, and RORγt, upregulating Bcl-6 and thus convert into Tfh. Limiting the numbers of Tfh within germinal centers is important in the regulation of the autoantibody production that is central to autoimmune diseases. Recently, it was revealed that the germinal center reaction and the size of the Tfh population are also regulated by thymus-derived follicular regulatory T cells (Tfr) expressing CXCR5 and Foxp3. Dysregulation of Tfh appears to be a pathogenic cause of autoimmune disease suggesting that tight regulation of Tfh and germinal center reaction by Tfr is essential for maintaining immune tolerance. Therefore, the balance between Tfh and Tfr appears to be a critical peripheral tolerance mechanism that can inhibit autoimmune disorders.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.63-72
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• 2020

Shadow banking in China has been growing rapidly; banks use wealth management products aggressively to evade regulatory constraints. The loan-to-deposit ratio or LDR targets both sides of the balance sheet; loans in terms of asset-side, and deposits in terms of liabilities-side; banks needed to control and maintain both sides. Regulators restricted Chinese banks to maintain a 75% limit for their loan-depositratio. Banks' needed to either lower their loans or increase the deposits; WMPs helped banks to evade this limit. Banks issue more WMPs to control and manage a 75% statutory ceiling LDR. This WMPs-LDR positive association disappeared post-2015 period. This study empirically examined how Chinese banks use WMPs issuance to avoid regulatory constraints. Quarterly panel data for 30 top Chinese banks were used by analyzing pre-2015 (during the 75% LDR limit) and post-2015 (after removal of the LDR limit). This study also performed fixed-effects model as recommended by the Hausman specification test, with feasible generalized least squares FGLS estimation technique. The results of this study show that for the pre-2015 period, Chinese banks use issuance of WMPs aggressively to manage their LDR limit; this WMPs-LDR relationship disappeared post-2015 period. Moreover, SMBs use WMPs more eagerly as compare to Big4 banks.

• Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.90-97
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• 2009

The cytoskeletal $\beta$-actin gene and its 5'-upstream region were isolated and characterized in the rockbream (Oplegnathus fasciatus). Complementary DNA of the rockbream $\beta$-actin represented a 1,125 bp of an open reading frame encoding 375 amino acids, and the rockbream $\beta$-actin cDNA and deduced amino acid sequences were highly homologous to those of other vertebrate orthologs. At the genomic level, the $\beta$-actin gene also exhibited an organization typical of vertebrate cytoskeletal actin genes (2,159 bp composed of five translated exons interrupted by four introns) with a conserved GT/AG exon-intron splicing rule. The putative non-translated exon predicted in the rockbream $\beta$-actin gene was much more homologous with those of teleostean $\beta$-actin genes than those of mammals. The 5'-upstream regulatory region isolated by genome walking displayed conserved and essential elements such as TATA, CArG and CAAT boxes in its proximal part, while several other immune- or stress-related motifs such as those for NF-kappa B, USF, HNF, AP-1 and C/EBP were in the distal part. Semi-quantitative RT-PCR assay results demonstrated that the rockbream $\beta$-actin transcripts were ubiquitously but different-tially expressed across the tissues of juveniles.