• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.82-82
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• 1997

The hepatitis B virus(HBV) is a small, enveloped virus with a circular, double-stranded DNA genome. HBV causes active and chronic hepatitis worldwide, including Korea, and is considered to be a major factor for liver cirrhosis and hepatocellular carcinoma. In contrast to the wealth of knowledge on the gene structure and expressional regulation, immunological and pathological mechanisms for HBV-induced hepatocellular injury are not well known. In the present study, vaccinia virus which has been demonstrated to be a useful eukaryotic expression vector was used to clone the gene for HBV surface antigen, L(S+preS2+preS1). The recombinant vaccinia virus vector, pMJ-L, which contains L surface antigen gene of adr-type HBV was constructed, and subseouently used for making recombinant vaccinia virus VV-$\textrm{HBV}_{L}$. Expression of the HBV antigen was examined by immunofluorescent antibody (IFA) test using mouse monoclonal anti-hepatitis B surface antigen. HBsAg was detected in the recombinant virus indicating that the VV-$\textrm{HBV}_{L}$ expressed S antigen successfully. The HBV-Vaccinia Virus recombinant obtained in this study is currently being used for studying the immunological aspects of HBV infection.

• Molecules and Cells
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• 제42권1호
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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.

• 대한바이러스학회지
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• 제27권2호
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• pp.143-149
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• 1997

Most of the current licenced hepatitis B vaccines are being produced by recombinant DNA technology in large fermentation cultures of Saccharomyces cerevisiae of yeast cells which carry the gene coded for hepatitis B virus surface antigen. These vaccines are proved very effective clinically and the immunogenicity of vaccines could be maintained for a long time under refrigeration. To develope the stabilizer that could increase the stability of hepatitis B virus vaccine which could be stored for a long period at room temperature or higher conditions, glucose, lactose and sucrose solutions in phosphate buffered saline were added into hepatitis B vaccine respectively to make 2.5%, 5%, 7.5% and 10% final concentration in vaccines. These sugar-vaccine mixtures were stored at room temperature for one month, two months and three months respectively and then inoculated into ICR mice intramuscularly. On the fourteenth day after inoculation, mice were bled and sera were tested for the evaluation of efficacies of vaccines. The results showed that 5% glucose, 7.5% lactose and sucrose increased the stability of vaccines in some degree and this method could be applied for the production of other viral vaccines and bacterial vaccines.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제5권1호
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• pp.39-50
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• 2002

Hepatitis B viral infection which affect about 10% of Korean population manifests asymptomatic carrier, chronic hepatitis and liver cirrhosis and even associates with hepatocellular carcinoma. Clinical manifestations induced by hepatitis B virus vary depending on the degree of immune response by cytotoxic T cells against viral epitope-presenting liver cells. Since hepatitis B virus presents high rate of mutaton that might change the presented epitope and eventually alter immune response, viral mutations, especially in promoters and enhancers, have an important implication in hepatic inflammation and viral replication. To identify mutations related to the hepatic inflammation, we investigated sequence variations of hepatitis B viral promotor regions in the presence or absence of symptoms in hepatitis B carriers. For this, sera from persistently hepatitis B virus-infected mother-child pairs were collected. After PCR amplifiation of all hepatitis B viral promoters (C promoter, S1 promoter, S2/S promoter, X promoter) using serum DNA from each pair, viral promotors were sequenced by automatic sequencer and then sequence data were analyzed by ClustalW. In most cases, the dominant type of maternal virus was transmitted to the child. However, in some children, some new host specific viral variants could be observed in Cp, S1p and S2/Sp. The mutations in C promoter did not seem to be vertically transmitted but arose in new host independently after the wild type had been transmitted. Enhancer I containing X promoter revealed high host specific variations as has been reported before. Two S promoters, S1p and S2/Sp, have shown some point mutations in children, but no deletion mutations were detected as in chronic hepatitis patients in whom deletion mutations are frequently found. In conclusion, the children with the vertically transmitted hepatitis B virus mostly retain the dominant type virus that had been transmitted. However, host specific variants tended to accumulate over time, possibly as clinical symptoms develop.

• 대한임상검사과학회지
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• 제43권2호
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• pp.57-67
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• 2011

In this study, we investigated the correlation between the administration of various antiviral agents and the alternation of specific biomarkers induced by the hepatitis B virus (HBV). Eligible subjects diagnosed with chronic hepatitis B were prescribed with antiviral drugs at the Gastroenterology Internal Medicine Department of E University Hospital in Daejeon between May 2004 and September 2009. Lamivudine was prescribed to 66 out of 100 patients. Of the 12 patients, 6 (50.0%) showed a change from being HBe-antigen-positive to being HBe-antigen-negative. Of the 39 patients, 23 (59.0%) showed higher than 40 IU/L alanine aminotransferase (ALT). Of the 65 patients, 41 (63.1%) showed HBV DNA decrease of 1 log, and were prescribed with Lamivudine. Adefovir was prescribed to 3 out of 100 patients. Of the 12 patients, 1 (8.3%) showed a change from being HBe-antigen-positive to being HBe-antigen-negative, and was prescribed with Adefovir. Entecavir was prescribed to 19 (19.0%) out of 100 patients. Of the 12 patients, 3 (25.0%) showed a change from being HBe-antigen-positive to being HBe-antigen-negative. Of the 12 patients, 3 (125.8%) showed higher than 40 IU/L ALT. Of the 65 patients, 14 (21.5%) showed HBV DNA decrease of 1 log, and were prescribed with Entecavir. Clavudine was prescribed to 7 out of 100 patients. Of the 12 patients, 1 (8.3%) showed a change from positive HBe antigen to negative HBe antigen. Of the 39 patients, 5 (12.8%) showed higher than 40 IU/L ALT. Of the 65 patients, 6 (9.2%) showed HBV decrease of 1 log, and were prescribed with Clavudine. These results do not show a statistically significant correlation between drugs and biomarkers. Data on combination therapy using Lamivudine and Adefovir show no statistically significant difference between drugs and biomarkers. Medications for periodic inspection was not correlated to HBe-antigen-negative conversion, ALT, and HBV DNA. HBV DNA was significantly reduced in patients with high levels of AST(aspartic acid aminotransferase) and ALT before treatment. In addition, the decrease of HBV DNA after 12 months of treatment was less frequently observed in patients treated with Lamivudine compared with other drugs. This result is associated with Lamivudine resistance. Although the association of drugs with diagnostic markers and the correct choice of treatment is difficult to determine, these results may be useful for further research on diagnosis and treatment of the hepatitis B virus.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.80.2-80.2
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• 2003

The nucleoside analogue, L-FMAUS was synthesized from L-FMAU which has been shown to have significant antiviral acitivity against hepatitis B virus (HBV). The anti-HBV activity and toxicity of the L-FMAUS were examined by a cell culture system using a hepatitis B virus (HBV) producing cell line, HepG2 2.2.15. L-FMAUS was assayed for the inhibition of HBV multiplication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium of HepG2 2.2.15 cells after an 8-day treatment. (omitted)

• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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• pp.331-337
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• 1993

In order to understand the effect of duck hepatitis B virus (DHBV) on the economic performance of ducks, Three groups (DHBV congenitally infected, experimentally infected and DHBV negative) Brown Tsaiya ducks (Anas platyrhyncha) were used for experimental animals. Artificial insemination and pedigree hatching were applied in the propagation of ducklings, and the efficiency of vertical transmission and experimental infection was analyzed through the detection of DHBV DNA in the sera of 8-week-old offspring. The observation of the records of the first year indicated that the persistent infection had no significant effects on the performance of ducks, except the egg number of survival ducks up to 40 week of age. Thus DHBV infection did not appear to give ill effects to the economic performance of ducks in first laying year. A higher infection rate (85.3%) was obtained in congenital transmission than that (75.5%) of experimental infection. Both modes of infection did not reach 100% infectious rate, although some ducks developed transient viraemia in a tracing of DHBV DNA for 24 weeks to 11 challenged ducklings.

• 생약학회지
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• 제30권3호
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• pp.238-243
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• 1999

This study was undertaken to test for anti-hepatitis B virus (HBV) activity of the aqueous extracts prepared from 9 medicinal plants of Korea (Cornus officinalis, Caesalpinia sappan, Rubus coreanus, Lycium chinense, Artemisia capillaris, Isatis tinctoria, Phyllanthus urinaria, Lysimachia christinae, Lonicera japonica). Aqueous extracts were tested for cytotoxicity and assayed for inhibition of HBV replication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium f HepG2 2.2.15 cells. The extract from Rubus coreanus, Artemisia capillaris, Phyllanthus urinaria decreased the levels of extracellular HBV virion DNA at concentrations ranging from 128 to $256\;{\mu}g/ml$ and inhibited the production fo HBsAg dose-dependently without showing cytotoxicity. Our findings suggest that these three hebal medicinal plants may have potential to develop as specific anti-HBV drugs in the future.

• Biomolecules & Therapeutics
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• 제9권2호
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• pp.131-139
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• 2001

Lamivudine, an oral nucleoside analogue, effectively inhibits hepatitis B virus replication and reduces hepatic necroinflammation in patients with chronic hepatitis B. Although lamivudine has shown a promise in patients with chronic hepatitis B, a long-term data on Korean patients with hepatitis B are lacking. The purpose of this study is to evaluate the effects and safety of 52-week lamivudine therapy in Korean patients with chronic hepatitis B, A total of twenty-nine patients (27 male and 2 female) who had received 100 mg of oral lamivudine daily for 52 weeks were evaluated, retrospectively. The mean age of 29 patients in the study group was 37.7 $\pm$ 8.9 years (range 19-54). Pretreatment HBV PCR and HBsAg were positive in all 29 patients, and HBeAg were positive in 25 patients (86%). The serum HBV DNA of 28 patients (97%) significantly fell to undetectable levels (<5 pg/ml) within 12 weeks of therapy and it remained undetectable in 24 patients (83%) by the end of 52-week therapy (p<0.001). Mean serum ALT levels of 29 patients declined to the normal range within 12 weeks and remained within the normal range during the evaluative period (p<0.05). The proportions of patients with HBeAg seroconversion (loss of HBeAg, development of antibody to HBeAg, and undetectable HBV DNA) were 42% after 52-week therapy. The differences of response to lamivudine therapy in HBeAg- positive and HBeAg-negative patients were negligible (p>0.05). Furthermore, the study showed that pretreatment serum HBV DNA and ALT levels have no effect to the efficacy of lamivudine therapy (p>0.05). Further comparison of lamivudine's efficacy showed that lamivudine is just as efficacious in patients with cirrhosis as without cirrhosis (p>0.05). In conclusion, lamivudine is an effective and safe therapy for the treatment of chronic hepatitis B in Korean patients.

• IMMUNE NETWORK
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• 제5권1호
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• pp.1-10
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• 2005

Background: Chronic infection with hepatitis B virus (HBV) affects about 350 million people worldwide, which have a high risk of development of cirrhosis and hepatocellular carcinoma. Treatment of chronic HBV infection relies on IFN-${\alpha}$ or lamivudine. However, interferon-${\alpha}$ is effective in only about 30% of patients. Also, the occurrence of escape mutations limits the usage of lamivudine. Therefore, the development and evaluation of new compounds or approaches are urgent. Methods: We comparatively evaluated DNA and adenoviral vaccines expressing HBV antigens, either alone or in combined regimens, for their ability to elicit Th1-type immune responses in Balb / c mice which are believed to be suited to resolve HBV infection. The vaccines were tested with or without a genetically engineered IL-12 (mIL-12 N220L) which was shown to enhance sustained Th1-type immune responses in HCV E2 DNA vaccine. Results: Considering the Th1-type cytokine secretion and the IgG2a titers, the strongest Th1-type immune response was elicited by the DNA prime-adenovirus boost regimen in the presence of mIL-12 N220L. In addition, the codelivery of mIL-12 N220L modulated differentially the immune responses by different vaccination regimens. Conclusion: Our results suggest that the DNA prime-adenovirus boost regimen in the presence of mIL-12 N220L may be the best candidate for HBV vaccine therapy of the regimens tested in this study and will be worthwhile being evaluated in chronic HBV patients.