• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.844-850
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• 2000

The specific binding and internalization of viral particles is an essential step for the successful infection of viral pathogens. In the case of the hepatitis B virus (HBV), virions bind to the host cell via the preS domain of the viral surface antigen and are subsequently internalized by endocytosis. HBV-preS specific receptors are primarily expressed on hepatocytes, however, viral DNA and proteins have also been detected in extrahepatic sites, suggsting that celluar recepators for HBV may also exist on extrahepatic cells. Recently, an EBV-transformed B-cell line was identified onto which the preS region binds in a receptor-ligand specific manner. In this study, this specific interaction was further characterized, and the binding region within the preS protein was locaized. Also the internalization after host cell attachment was visualized and analyzed by fluorescence-labeled HBV-preS1 proteins using confocal microscopy. Energy depletion by sodium azide treatment effectively inhibited the internalization of the membrane-bound preS1 ligands, thereby indicating an energy-dependent receptor-mediated endocytotic pathway. Accordingly, the interaction of HBV-pres! with this specific B-cell line may serve as an effective model for an infection pathway in extrahepatic cells.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.140-144
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• 2007

Polygonum cuspidatum has been used as treatments of dermatitis, gonorrhea, inflammation, and hyperlipidaemia in traditional medicine. We examined liver protective effect on CCl$_4$ inducing hepatotoxicity and anti-oxidative activity by TBA method. Phytochemical examination of Polygonum cuspidatum led to the isolation and characterization of emodin 8-O-${\beta}$-D-glucopyranoside (compound 1), and trans-resveratrol 3-O-${\beta}$-D-glucopyranoside (compound 2). Compounds 1 and 2 enhanced the inhibition of anti-lipid peroxidative effects in liver homogenate. In chemical parameters obtained from serum analysis, compounds 1 and 2 also revealed significant decrease in hepatotoxicity. These results suggested that the antraquinone and stilbene which were isolated from Polygonum cuspidatum might be used as therapeutic agent of hepatitis.

• Natural Product Sciences
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• v.26 no.4
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• pp.289-294
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• 2020

Eclipta prostrata is an annual herb, belonging to Asteraceae family, and has been traditionally used to improve immunity and treat hepatitis and bacterial disease in Korea. In this study, a new coumestan glucoside (1) along with ten known compounds (2 - 11) was isolated from E. prostrata. The chemical structures of isolates were elucidated to be wedelolactone-9-O-β-D-glucopyranoside (1), wedelolactone (2), demethylwedelolactone (3), apigenin (4), apigenin-7-sulfate (5), luteolin (6), luteolin-7-sulfate (7), luteolin-7-O-β-D-glucopyranoside (8), pratensein-7-O-β-D-glucopyranoside (9), 3,4-di-O-caffeoylquinic acid (10) and 3,5-di-O-caffeoylquinic acid (11) based on the spectroscopic evidence.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.823-828
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• 2000

The complete nucleotide sequence of hepatitis B virus DNA isolated from Korean patient serum was determined and characterized, and its phylogenetic relation was then investigated. The viral genome was 3,215 base pairs long and included four well known open reading frames (i.e. surface antigens, core antigens, X protein and DNA polymerase). The sequence of the surface antigen showed that the HBV genome under investigation, designated HBV 315, was characteristic of subtype adr. A phylogenetic analysis using the total genome sequence revealed that HBV315 was grouped into genomic group C together with isolates from Japan, China, Thailand, Polynesia, and New Caledonia. The mean percent similarity between HBV315 and other HBV isolates in genomic group C was 97.25%, and that with other genomic groups ranged from 86.16% to 91.25%. The predicted amino acid sequences of HBV315 were compared with two closely related subtype adr isolates, M38636 and D12980. The results showed that the X gene product was identical in the three strains, while there were significant amino acid sequence differences between HBV315 and M38636 in the Pre-S1 and Pre-S2 regions.

• BMB Reports
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• v.37 no.5
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• pp.546-551
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• 2004

The increasing pace of development in molecular biology during the last decade has had a direct effect on mass testing and diagnostic applications, including blood screening. We report the model Microarray that has been developed for Hepatitis B virus (HBV) and Hepatitis D virus (HDV) detection. The specific primer pairs of PCR were designed using the Primer Premier 5.00 program according to the conserved regions of HBV and HDV. PCR fragments were purified and cloned into pMD18-T vectors. The recombinant plasmids were extracted from positive clones and the target gene fragments were sequenced. The DNA microarray was prepared by robotically spotting PCR products onto the surface of glass slides. Sequences were aligned, and the results obtained showed that the products of PCR amplification were the required specific gene fragments of HBV, and HDV. Samples were labeled by Restriction Display PCR (RD-PCR). Gene chip hybridizing signals showed that the specificity and sensitivity required for HBV and HDV detection were satisfied. Using PCR amplified products to construct gene chips for the simultaneous clinical diagnosis of HBV and HDV resulted in a quick, simple, and effective method. We conclude that the DNA microarray assay system might be useful as a diagnostic technique in the clinical laboratory. Further applications of RD-PCR for the sample labeling could speed up microarray multi-virus detection.

• KSBB Journal
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• v.15 no.2
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• pp.214-218
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• 2000

A hepatitis B Surface Antigen(HBsAg)-screening kit using immunochromatographic assay(ICA) method was developed by e employing two kinds of antibodies. One is mouse monoclonal anti-HBs for tracer antibody and the other is goat p이yclonal a anti-HBs for capture antibody. This capture antibody was immobilized on the surface of nitroceliulose(NC) membrane and the t tracer antibody was conjugated with g미d particles. When serum sample was added to the sample well, the $\infty$njugates d deposited in a dry state on the surface of glass fiber filter were reconstituted and then combined with HBsAg in serum. In 5 5 min after adding, the assay result was visible through the window, that is, the complexes composed of HBsAg and the c conjugates appeared as maroon line on the lower part of the NC membrane. The detection limit of the ICA kit was 2 ng/ml w when being tested with the reference HBsAg.

• YAKHAK HOEJI
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• v.51 no.3
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• pp.194-198
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• 2007

The mouse hepatitis virus (MHV-2) induces broad collapses, focal necrosis and cytolysis of hepatocytes, and leads to death after three to five days of intraperitoneal injection in mice. The present study investigated whether the combinatorial treatment of dimethyl dicarboxylate/amantadine (2:1) showed hepatoprotective and/or antiviral properties in MHV-2 infected ICR mice. In the study, we found that dimethyl dicarboxylate/amantadine group (VDDBA) increased the survival rate (30.8%) when compared to positive control, VL (7.7%) and that VDDBA lengthened the survival time (4.2 d)after MHV-2 infection. In addition, ALT and AST were well regulated when treated with VDDBA (p<0.01). Finally, we concluded that those results were probably from the inhibition of viral replication and at least antiproliferative effect on MHV-2.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1634-1639
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• 2006

Hepatitis C virus (HCV)-encoded nonstructural protein 5B (NS5B) possesses RNA-dependent RNA polymerase activity, which is considered essential for viral proliferation. Thus, HCV NS5B is a good therapeutic target protein for the development of anti-HCV agents. In this study, we isolated two different kinds of nuclease-resistant RNA aptamers with 2'-fluoro pyrimidines against the HCV NS5B from a combinatorial RNA library with 40 nucleotide random sequences, using SELEX technology. The isolated RNA aptamers were observed to specifically and avidly bind the HCV NS5B with an apparent $K_d$ of 5 nM and 18 nM, respectively, in contrast with the original RNA library that hardly bound the target protein. Moreover, these aptamers could partially inhibit RNA synthesis of the HCV subgenomic replicon when transfected into Huh-7 hepatoma cell lines. These results suggest that the RNA aptamers selected in vitro could be useful not only as therapeutic agents of HCV infection but also as a powerful tool for the study of the HCV RNA-dependent RNA polymerase mechanism.

• Molecules and Cells
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• v.42 no.1
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• pp.67-78
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• 2019

Methylation of HBV cccDNA has been detected in vivo and in vitro; however, the mechanism and its effects on HBV replication remain unclear. HBx derived from a 1.2-mer HBV replicon upregulated protein levels and enzyme activities of DNA methyltransferase 1 (DNMT1), 3a, and 3b, resulting in methylation of the negative regulatory region (NRE) in cccDNA, while none of these effects were observed with an HBx-null mutant. The HBx-positive HBV cccDNA expressed higher levels of HBc and produced about 4-fold higher levels of HBV particles than those from the HBx-null counterpart. For these effects, HBx interrupted the action of NRE binding protein via methylation of the C-1619 within NRE, resulting in activation of the core promoter. Treatment with 5-Aza-2′dC or DNMT1 knock-down drastically impaired the ability of HBx to activate the core promoter and stimulate HBV replication in 1.2-mer HBV replicon and in vitro infection systems, indicating the positive role of HBx-mediated cccDNA methylation in HBV replication.

• Childhood Kidney Diseases
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• v.9 no.2
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• pp.143-148
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• 2005

Purpose : Hypogammaglobulinemia has been observed in nephrotic syndrome, but its pathophysiology remains unknown. We evaluated serum immunoglobulins, IgG subclasses, and vaccine-induced viral antibodies(anti-hepatitis B surface IgG and anti-measles IgG) in children with minimal change nephrotic syndrome(MCNS). Methods : Using the stored sera, the levels of immunoglobulin(IgC, IgM, IgA, and IgC) and IgG subclasses(IgG 1, 2, ,3, and 4), anti-HBs Ab and anti-measles IgG of 21 children with MCNS were analyzed and compared to those of 25 age-matched healthy children. Results : The mean values of IgG and IgG1 were $390{\pm}187\;mg/dL$ and $287{\pm}120\;mg/dL$ in nephrotic children, and $1,025{\pm}284\;mg/dL$ and $785{\pm}19\;mg/dL$ in control children, respectively. The values of the total IgG and the 4 IgG subclasses in nephrotic children were all significantly depressed(P<0.001), but the IgM($251{\pm}183\;mg/dL\;vs. 153{\pm}55\;mg/dL$, P=0.02) and IgE values(P=0.01) were elevated, and the IgA values were not changed. The seropositivity of anti-HBs IgG was 42.9$\%$(9 of 21 cases) in the MCNS group and 52$\%$(13/25) in the control group, and that of anti-measles IgG was 75$\%$(16/21) and 92$\%$(23/25), respectively, but there was no statistical difference between the two groups. Conclusion : IgG and IgG subclass levels in MCNS children are all depressed without significant seronegativity of the vaccine-induced viral antibodies. Further studies are needed to resolve the cause of hypogammaglobulinemia in MCNS. (J Korean Soc Pediatr Nephrol 2005;9:143-148)