• Journal of Microbiology
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• v.37 no.2
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• pp.90-96
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• 1999

The core protein of the hepatitis C virus (HCV) is a multifunctional protein. The HCV core protein was reported to regulate cellular gene expression and transform primary rat embryo fibroblast cells. However, the role of the core protein in the pathogenesis of HCV-associated liver diseases is not well understood. To investigate the functional role of the core protein in cytophathogenicity, we have constructed stable expression systems of full length or truncated HCV core protein lacking the C-terminal hyderophobic domains and established HepG2 cell clones constitutively expressing the core protein. The full length core protein was localized in the cytoplasm and the C-terminal truncated core protein was localized in the nucleus. HepG2 cells expressing nuclear, truncated core protein showed elevated cell death during cultivation compared to untransfected cells and full length core-expressing cells. In the treatment with bleomycin, both cell clones expressing full length or truncated core protein appeared to be more sensitive to blemoycin than the parental HepG2 cells. These results suggest that the core protein may play a role in HCV pathogenesis promoting apoptotic cell death of infected cells.

• Journal of the Korean Magnetic Resonance Society
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• v.21 no.3
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• pp.109-113
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• 2017

The hepatitis C virus (HCV) internal ribosome entry site (IRES) is an RNA structure located in the 5'-UTR of the HCV RNA genome. The HCV IRES consists of four domains I, II, III, and IV, where domains II - IV are recognized by 40S ribosomal subunit and the domain III is bound to eukaryotic initiation factor 3 (eIF3) for translation initiation. Here, we have characterized the tertiary interaction between an L-/K- rich peptide and the HCV IRES domain IV. To probe the peptide binding interface in RNA, we synthesized $^{13}C$- and $^{15}N$-double labeled RNA and the binding site was identified by using the chemical shift perturbation (CSP) NMR methods. Our results showed that the peptide binds to the upper stem of the IRES domain IV, indicating that the tertiary interaction between the IRES domain IV and the peptide would disrupt the initiation of translation of HCV mRNA by blocking the start codon exposure. This study will provide an insight into the new peptide-based anti-viral drug design targeting HCV IRES RNA.

• BMB Reports
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• v.36 no.6
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• pp.538-544
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• 2003

The hepatitis C virus (HCV) is a major causative agent of chronic hepatitis and hepatocellular carcinoma. The development of alternative antiviral therapies is warranted because current treatments for the HCV infection affect only a limited number of patients and lead to significant toxicities. The HCV genome is exclusively present in the RNA form; therefore, ribozyme strategies to target certain HCV sequences have been proposed as anti-HCV treatments. In this study, we determined which regions of the internal ribosome entry site (IRES) of HCV are accessible to ribozymes by employing an RNA mapping strategy that is based on a trans-splicing ribozyme library. We then discovered that the loop regions of the domain IIIb of HCV IRES appeared to be particularly accessible. Moreover, to verify if the target sites that were predicted to be accessible are truly the most accessible, we assessed the ribozyme activities by comparing not only the trans-splicing activities in vitro but also the trans-cleavage activities in cells of several ribozymes that targeted different sites. The ribozyme that could target the most accessible site identified by mapping studies was then the most active with high fidelity in cells as well as in vitro. These results demonstrate that the RNA mapping strategy represents an effective method to determine the accessible regions of target RNAs and have important implications for the development of various antiviral therapies which are based on RNA such as ribozyme, antisense, or siRNA.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.1
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• pp.88-92
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• 2009

Although transfusion of blood and plasma products are accepted as the principle means of transmission of HCV, other parenteral methods, such as acupuncture, tattooing needles, piercing, and surgery are possible methods of transmission of HCV. We managed a case of chronic hepatitis C acquired through ear piercing and acupuncture. A 10-year old girl presented with nausea, abdominal pain, and anorexia for 1 month. Her laboratory finding showed the following: AST/ALT, 865/1,290 IU/L; positive anti-HCV Ab; and HCV RNA. One year previously, she was treated with acupuncture for an ankle sprain and 2 years previously, she had her ears pierced. Laboratory findings of family members showed AST/ALT in the normal ranges, and negative anti-HCV Ab and HCV RNA. The pathologic findings of a liver biopsy revealed chronic hepatitis with mild lobular activity, moderate porto-periportal activity, and portal fibrosis. She was treated with pegylated interferon ${\alpha}$-2a and oral ribavirin for 6 months, after which the clinical symptoms and laboratory findings improved.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.159-165
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• 2007

For the development of basic genetic materials for specific and effective therapeutic approach to suppress multiplication of hepatitis C virus (HCV), HCV internal ribosome entry site (IRES)-targeting hammerhead ribozyme which activity is allosterically regulated by HCV regulatory protein, NS5B RNA replicase, was developed. The ribozyme targeted most effectively to +382 nucleotide (nt) site of HCV IRES RNA. The allosteric ribozyme was designed to be composed of sequence of RNA aptamer to HCV NS5B, communication module sequence which can transfer structural transition for inducing ribozyme activity upon binding NS5B to the aptamer, and sequence of ribozyme targeting +382 nt of HCV IRES. Noticeably, we employed in vitro selection technology to identify the most appropriate communication module sequence which can induce ribozyme activity depending on the US5B protein. We demonstrated that the ribozyme was nonfunctional either in the absence of any proteins or in the presence of control bovine serum albumin. In sharp contrast, the allosteric ribozyme can induce activity of cleavage reaction with HCV IRES RNA in the presence of the HCV NS5B protein. This allosteric ribozyme can be used as lead compound for specific and effective anti-HCV agent, tool for highthroughput screening to isolate lead chemicals for HCV therapeutics, and ligand for biosensor system for HCV diagnosis.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.526-541
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• 1995

This study was conducted to estimate the validity of reverse transcriptase-polymerase chain reaction(RT-PCR) compared to enzyme immunoassay(EIA) for the detection of hepatitis C virus (HCV) infection. EIA for antibody to HCV(anti-HCV) and RT-PCR for HCV was executed on the subjects from Pusan and Kyungnam area with questionnaire survey to collect some relating factors of HCV infection. As the result from 617 cases, the prevalence of HCV infection was 1.5% by EIA and 3.7% by RT-PCR(p<0.05), and the age standardized rate was 1.7% and 3.4% by EIA and RT-PCR, respectively. The prevalence of hepatitis B surface antigen(HBsAg) was 6.8% by enzyme linked immunosorbent assay(ELISA) and the age standardized rate was 7.7%. It was the higher in male group comparing to female group(p<0.01). Both of the prevalence of HCV and HBsAg were higher in elevated asparate aminotransferase(AST) and alanine aminotransferase (ALT) group than in normal AST and ALT group(p<0.01). There was no specific risk factor of HCV infection. Though the degree of agreement of EIA and RT-PCR by gamma statistics was 97.2%, it showed a significant difference between the two methods(p<0.01). For the detection of HCV infection, positive predictive value of EIA was 66.7% and negative predictive value of EIA was 97.2%. This study suggests that negative result to anti-HCV by EIA didn't mean the free state of HCV infection, therefore it would be helpful that further monitoring for HCV infection by RT-PCR in the case of elevated AST and ALT and/or clinically suspected.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1147-1151
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• 2009

The synthetic route of novel 3′-C-methyl carbodine analogue is described. The construction of tertiary alcohol at 3′- position of carbodine analogues was successfully made via sequential [3,3]-sigmatropic rearrangement, ring-closing metathesis (RCM) and stereoselective dihydroxylation reactions starting from ethyl glycolate.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.1953-1954
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• 2013

• Journal of Life Science
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• v.28 no.9
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• pp.1007-1015
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• 2018

The E6-associated protein (E6AP) is known to induce the ubiquitination and proteasomal degradation of HCV core protein and thereby directly impair capsid assembly, resulting in a decline in HCV replication. To counteract this anti-viral host defense system, HCV core protein has evolved a strategy to inhibit E6AP expression via DNA methylation. In the present study, we further explored the mechanism by which HCV core protein inhibits E6AP expression. HCV core protein upregulated both the protein levels and enzyme activities of DNA methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b to inhibit E6AP expression via promoter hypermethylation in HepG2 cells but not in Hep3B cells, which do not express p53. Interestingly, p53 overexpression alone in Hep3B cells was sufficient to activate DNMTs in the absence of HCV core protein and thereby inhibit E6AP expression via promoter hypermethylation. In addition, upregulation of p53 was absolutely required for the HCV core protein to inhibit E6AP expression via promoter hypermethylation, as evidenced by both p53 knockdown and ectopic expression experiments. Accordingly, levels of the ubiquitinated forms of HCV core protein were lower in HepG2 cells than in Hep3B cells. Based on these observations, we conclude that HCV core protein evades ubiquitin-dependent proteasomal degradation in a p53-dependent manner.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.235-238
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• 2016

Hepatitis C is an ailment of liver caused by hepatitis C virus (HCV) infection. About 3% of the world population is infected by this virus. HCV infection is a leading reason for liver cirrhosis and therefore a major source of hepatocellular carcinoma. The study focused on the incidence of active HCV infection in blood donors of Mardan district of KPK, Pakistan. A total of 5318 blood donors were inspected for the presence of anti-HCV antibodies and HCV-RNA using ICT (immune-chromatographic test), ELISA and RT-PCR at Mardan Medical Complex (MMC), Mardan. Out of these, 157 (2.95%) were positive by ICT, 60 (1.12%) by ELISA and 56 (1.05%) for HCV-RNA. The frequency of active HCV infectivity amongst the blood donors from district Mardan, KPK Pakistan was 1.05 %. Application of strict measures during blood donor selection and use of proper screening assays such as ELISA in place of ICT devices can give a more accurate picture so that the incidence of this viral infection in HCV negative blood recipients can be reduced.