• BMB Reports
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• v.41 no.9
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• pp.640-644
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• 2008

The preS1 surface protein of the hepatitis B virus (HBV) is a key factor involved in initial viral entry into hepatocytes. It has been long postulated that an anti-HBV effect should be achievable using peptide fragments of the preS1. Recent reports demonstrated that several preS1-derived lipo-peptides in genotype D HBV exhibit nano to picomolar inhibitory activity against HBV infection. In this study, an acylated analog of a preS1 fragment, a 21-residue lipo-peptide (named 7524 BVS7) with a sequence of palmitoyl-GMGTNLSVPNPLGFFPDHQLDC-$NH_2$, from genotype C HBV was produced base upon a previous structural study and was shown potently inhibits HBV infection with an $IC_{50}$ of $\approx$ 20 nM.

• Molecules and Cells
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• v.21 no.3
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• pp.330-336
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• 2006

Since its identification in 1989, hepatitis C virus has been the subject of extensive research. The biology of the virus and the development of antiviral drugs are closely related. The RNA polymerase activity of nonstructural protein 5B was first demonstrated in 1996. NS5B is believed to localize to the perinuclear region, forming a replicase complex with other viral proteins. It has a typical polymerase structure with thumb, palm, and finger domains encircling the active site. A de novo replication initiation mechanism has been suggested. To date, many small molecule inhibitors are known including nucleoside analogues, non-nucleoside analogues, and pyrophosphate mimics. NS5B interacts with other viral proteins such as core, NS3, 4A, 4B, and 5A. The helicase activity of NS3 seems necessary for RNA strand unwinding during replication, with other nonstructural proteins performing modulatory roles. Cellular proteins interacting with NS5B include VAMP-associated proteins, heIF4AII, hPLIC1, nucleolin, PRK2, ${\alpha}$-actinin, and p68 helicase. The interactions of NS5B with these proteins might play roles in cellular trafficking, signal transduction, and RNA polymerization, as well as the regulation of replication/translation processes.

• Molecules and Cells
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• v.25 no.4
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• pp.545-552
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• 2008

A hepadnaviruses replicates its DNA genome via reverse transcription of an RNA template (pregenomic RNA or pgRNA), which has a cap structure at the 5' end and a poly(A) tail at the 3' end. We have previously shown that the 5' cap is indispensable for encapsidation of the pgRNA. A speculative extension of the above finding is that the cap contributes to encapsidation via its interaction with the poly(A) tail, possibly involving eIF4E-eIF4G-PABP interaction. To test this hypothesis, poly(A)-less pgRNAs were generated via cleavage by a cis-acting hepatitis delta virus ribozyme sequence. We found that accumulation of the poly(A)-less pgRNA was markedly diminished, mostly likely due to its reduced stability. Importantly, however, the remaining poly(A)-less pgRNAs were nonetheless encapsidated and reverse transcribed normally when the reduced stability was taken account. Our finding clearly contradicts the notion that the poly(A) tail has any function in encapsidation and viral reverse transcription.

• Microbiology and Biotechnology Letters
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• v.48 no.4
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• pp.564-568
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• 2020

Although studies on Hepatitis A virus (HAV) were crucial in the establishment of the HAV infection prevention programs, no systematic investigation into HAV has been conducted since 1999. We retrospectively analyzed the data between January 2010 to December 2018 from all the patients who underwent HAV antibody tests at the Dankook University Hospital Health Care Center. Data were collected from 56,204 individuals. Overall, 34,834 (62.0%) individuals from this cohort were positive for HAV antibodies and the annual rate of anti-HAV antibody positivity was highest in 2010 (68.5%) and lowest in 2013 (54.8%). The average decline in the antibody positivity rate was 0.62% per year, showing a statistically significant difference (p < 0.001). In the over 40s age group, anti-HAV antibody positivity rates decreased from 89% in 2010 to 64% in 2018 (p < 0.001), with an annual decrease of 3.1%. In the over 30s age group, it decreased from 48.2% in 2010 to 34.7% in 2018 (p < 0.001), with an annual decrease of 1.82%. This study shows that the antibody positivity rate is decreasing across age groups but given that HAV infection poses more significant risks in older patients it is important to expand the evaluations of the current and future antibody positivity rates for HAV in various age groups.

• Korean Journal of Microbiology
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• v.29 no.2
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• pp.80-84
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• 1991

We cloned and expressed hepatitis B viral core antigen (HBcAg) gene in E. coli using $P_{L}$ promoter system. For optimal expression of the gene, we undertook the studies on the effects of the distance between Shine-Dalgarno (SD) sequence and start codon, copy number of repressor gene, induction temperature, and the stability of the core antigen. The results demonstrated that the induction at 37.deg.C was more efficient than at 42.deg.C, and the 11 base pairs (bp) distance between SD sequence and start codon of HBcAg gene was more efficient than the 15 bp distance in E. coli. The copy number of cI857 repressor gene did not influence on the expression of HBcAg, and the expression level of HBcAg in mutant type (low protease activity) and wild type strains was almost the same. The produced core antigen appeared to be HBcAg not HBeAg judged by two different radioimmunoassat (RIA) kits. This result suggested that the antigen was stable in E. coli.i.

• Journal of Microbiology and Biotechnology
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• v.20 no.12
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• pp.1769-1771
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• 2010

The envelope glycoprotein E2 of hepatitis C virus (HCV) binds to various cell surface receptors for viral infection. We performed biopanning against this protein and selected peptides from phage display peptide libraries. Two short peptides, pep7-1 and pep12-1, were selected and their ability to inhibit the infection process was investigated. When pep7-1 was present, the infectivity of HCV particles in cell culture was notably decreased. This decrease was demonstrated by Western blot analysis, immunofluorescence assay, and reverse transcription PCR assay. However, pep12-1 showed little inhibitory effect on HCV infection.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.450-455
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• 2017

Chronic liver disease, one of the most common diseases, typically arises from nonalcoholic fatty liver disease, alcoholic liver disease, chronic viral hepatitis, or hepatocellular carcinoma. Therefore, there is a pressing need for improved treatment strategies. Korean Red Ginseng has been known to have positive effects on liver disease and liver function. In this paper, we summarize the current knowledge on the beneficial effects of Korean Red Ginseng on chronic liver disease, a condition encompassing nonalcoholic fatty liver disease, alcoholic liver disease, chronic viral hepatitis, and hepatocellular carcinoma, as supported by experimental evaluation and clinical investigation.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.101-109
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• 2000

Duck viral hepatitis is an acute, highly infectious viral disease of young dacklings aged from two days to three weeks. The significant lesion associated with the disease was enlarged liver including necrotic foci and numerous hemorrhagic spots. We have isolated five strains of duck hepatitis virus (DHV) from field cases showing about 20% mortality with a sign of opisthotonos. When a-day-old ducklings were intramuscularly inoculated with one of the isolates, 92% of the birds were died within 5 days. We attempted to develop an attenuated strain of duck hepatitis virus (DHV) using one of the isolates by serial chicken embryo passages. The propagation of DHV in chicken embryos was carried 140 passages. The virus titer increased gradually from the $21^{st}$ through the $50^{th}$ passage, but there was no significant increase of virus titer in subsequent passages after then. Through the serial passages, the virulence of the virus for chicken embryos was gradually increased but decreased for ducklings. The pathogenicity of the virus for ducklings was preserved up to the $21^{st}$ passage but disappeared at the $50^{th}$passage. An attenuated Korean isolate which was passaged 140 times in chicken embryos gave good protection in ducklings against both challenge infection to a Korean virulent strain and to a DHV-DRL strain, a type 1 reference strain of DHV, which indicated that the Korean isolates could be classified as DHV type 1. And the above results suggest that an attenuated Korean isolate can be used for developing a live DHV vaccine.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.9 no.2
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• pp.242-248
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• 2006

Purpose: Neonatal hepatitis is the major cause of neonatal cholestasis and may be divided into infectious, metabolic, genetic, and idiopathic neonatal hepatitis. Non-familial, non-metabolic, and non-A, B, C viral neonatal hepatitis is known to have made satisfactory progress, but little is known about its chronic clinical features. Methods: Clinical and histological assessments were carried out in 34 cases with chronic neonatal hepatitis [elevated serum alanine aminotrasferase (ALT) level for more than 6 months] except for A, B, C viral hepatitis, metabolic, or genetic neonatal hepatitis, who were admitted to the Department of Pediatrics, Pusan National University Hospital, from January 1998 to January 2004. Results: Males were more common (70%). Jaundice (100%) and hepatomegaly (44%) were frequent manifestations. Peak serum ALT levels were most commonly below 300 IU/L in 41.2% of patients and peak serum direct bilirubin levels were most commonly between 1.0~5.0 mg/dL in 50% of patients. Ten cases (34%) of 29 patients had positive serum cytomegalovirus (CMV) IgM or urine CMV polymerase chain reaction. Serum ALT level was normalized within 1 year in 11 (37.9%) of 29 cases, and within 2 years in 9 (69.2%) of 13 cases. Serum ALT level was elevated persistently over 2 years in four (30.7%) of 13 cases. Histologic findings such as portal or periportal activity, lobular necrosis, portal or periportal fibrosis were more severe in patients with persistent ALT elevation over 2 years than in those showing normalization of ALT within 2 years (p>0.05). Conclusion: When the elevation of ALT level sustains over 1 year in non-familiar, non-metabolic, non-A, B, C viral neonatal hepatitis, an assessment of the severity of liver injury and a careful monitoring about chronic liver disease may be required.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.211-220
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• 1985

Serum HBsAg, AntiHBs, HBeAg, AntiHBe and AntiHBc were detected by radioimmunoassay in 39 patients with acute viral hepatitis, 79 patients with chronic hepatitis, 30 patients with liver cirrhosis, 16 patients with primary hepatocellular carcinoma, 14 patients of HBsAg carriers and 129 cases of controls:78 cases of normal level of SGOT, SGPT, and 51 cases of elevated level of SGOT, SGPT. Following results were obtained: 1. HBsAg was detected in 66.7% of acute viral hepatitis, 63.3% of chronic hepatitis, 36.7% of liver cirrhosis, 81.3% of primary hepatocellular carcinoma and 27.1% of controls. 2. AntiHBs was positive in 0% of acute viral hepatitis, 21.5% of chronic hepatitis, 36.7% of liver cirrhosis, 31.3% of primary hepatocellular carcinoma, 0% of carrier and 44.2% of controls. 3. HBeAg was detected in 45.6% of chronic hepatitis, 23.3% of liver cirrhosis and 31.3% of primary hepatocellular carcinoma. 4. Among chronic liver diseases, antiHBe was positive in 56.3% of primary hepatocellular carcinoma, 23.3% of liver cirrhosis and 20.3% of chronic hepatitis. 5. AntiHBc was detected in most of all examines and the significance of presence of AntiHBc does not seem to represent liver disease itself but the evidence of infection of HBV. 6. Among 14 HBV carriers, 6 cases presented with abnormal SGOT, SGPT. 7. All HBV markers were negative in 5.1% of acute viral hepatitis, 5.1% of chronic hepatitis and 14.7% of controls: 17.6% of subjects with abnormal SGOT, SGPT and 12.8% of subjects with normal SGOT, SGPT. 8. Beside of HBV, other causes, such as non A, non B virus, Delta-agent, other viruses or related factors should be excluded among the patients with evidence of HBV infection associated with elevation of SGOT & SGPT.