• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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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.

• Korean Journal of Poultry Science
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• v.38 no.1
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• pp.13-19
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• 2011

In January 2010, high mortalities of ducklings occurred in two adjacent farms. Ducklings in farm A showed neurologic signs including paddling, opisthotonus and lameness, but ducklings from farm B had no specific clinical signs. At post mortem, diffused hemorrhagic spots in the liver and hemorrhages in the small intestine were observed in ducklings from farm A, and ducklings from farm B had only proventricular ulceration. Microscopically, multiple necrosis of hepatocytes, hyperplasia of the bile ducts, hemorrhages, infiltration of lymphocytes and bacterial colonies were commonly observed in the liver of ducklings from both farms. Also, type A and C duck hepatitis virus (DHV) were isolated from farm A and farm B, respectively and Salmonella typhimurium was commonly isolated and identified serologically and biochemically. To our knowledge, this is the first report about the co-infection of DHV and Salmonella typhimurium in ducklings, and co-circulation of type A and C duck hepatitis viruses in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2865-2869
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• 2013

Hepatitis B virus (HBV) infection can become chronic and if left untreated can progress to hepatocellular carcinoma (HCC).Thailand is endemic for HBV and HCC is one of the top five cancers, causing deaths among Thai HBV-infected males. A single nucleotide polymorphism (SNP) at the KIF1B gene locus, rs17401966, has been shown to be strongly associated with the development of HBV-related HCC. However, there are no Thai data on genotypic distribution and allele frequencies of rs17401966. Thai HBV patients seropositive for HBsAg (n=398) were therefore divided into two groups: a case group (chronic HBV with HCC; n=202) and a control group (HBV carriers without HCC; n=196). rs17401966 was amplified by polymerase chain reaction (PCR) and analyzed by direct nucleotide sequencing. The genotypic distribution of rs174019660 for homozygous major genotype (AA), heterozygous minor genotype (AG) and homozygous minor genotype (GG) in the case group was 49.5% (n=100), 40.1% (n=81) and 10.4% (n=21), respectively, and in controls was 49.5% (n=97), 42.3% (n=83) and 8.2% (n=16). Binary logistic regression showed that rs17401966 was not statistically associated with the risk of HCC development in Thai chronic HBV patients (p-value=0.998, OR=1.00 and 95% CI=0.68-1.48). In conclusion, the KIF1B gene SNP (rs174019660) investigated in this study showed no significant association with HBV-related HCC in Thai patients infected with HBV, indicating that there must be other mechanisms or pathways involved in the development of HCC.

• Journal of Korean society of Dental Hygiene
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• v.3 no.2
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• pp.89-99
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• 2003

This study aims to furnish basic data about prevention and infection control of Hepatitis B Virus(HBV) for those who, working in dental offices, are particularly exposed to a high risk of HBV infection. A survey was conducted to 310 students including freshmen, sophomores and juniors enrolled in the dental hygiene department in order to examine their knowledge about infection routes of HBV, clinical history of their family members and their own health. The outcomes of the survey showed following facts; 1. Students were found to lack knowledge about the present conditions of their HBsAg and HBsAb of HBV(PF0.05), conduct of preventive vaccination(PE0.05), completion of 3 required vaccinations(PF0.05) and formation of antibody(PF0.05). 2. Students named "blood"(88.6%) and "infected needles"(82.5%) as most likely infection routes of HBV(PE0.05 and PE0.01). These replies came mostly from sophomores(65.6% and 92.1%), followed by juniors(89.2%, 82.5%) and freshmen(81.1%, 73.0%). Least knowledge about infection routes of HBV was sensed with the reply "infection through breast-feeding of positive mother(27.9%)"(PE0.05). Generally, sophomores seemed to have much knowledge about infection routes, followed by juniors and freshmen in order. 3. As to clinical history of family members, 10 students(3.5%) replied that any of their family members is suffering from HBV now, 8(2.6%) revealed that some of their family members once suffered from it and 10(3.2%) reported cases of death of their family members from liver diseases. 4. Ninety-four point seven percent of respondents believed their health to be better than normal.

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1376-1383
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• 2018

The hepatitis B virus (HBV) envelope contains small (S), middle (M), and large (L) proteins. PreS1 of the L protein contains a receptor-binding motif crucial for HBV infection. This motif is highly conserved among 10 HBV genotypes (A-J), making it a potential target for the prevention of HBV infection. In this study, we successfully generated a neutralizing human monoclonal antibody (mAb), 1A8 (IgG1), that recognizes the receptor-binding motif of preS1 using a phage-displayed human synthetic Fab library. Analysis of the antigen-binding activity of 1A8 for different genotypes indicated that it can specifically bind to the preS1 of major HBV genotypes (A-D). Based on Bio-Layer interferometry, the affinity ($K_D$) of 1A8 for the preS1 of genotype C was 3.55 nM. 1A8 immunoprecipitated the hepatitis B virions of genotypes C and D. In an in vitro neutralization assay using HepG2 cells overexpressing the cellular receptor sodium taurocholate cotransporting polypeptide, 1A8 effectively neutralized HBV infection with genotype D. Taken together, the results suggest that 1A8 may neutralize the four HBV genotypes. Considering that genotypes A-D are most prevalent, 1A8 may be a neutralizing human mAb with promising potential in the prevention and treatment of HBV infection.

• IMMUNE NETWORK
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• v.10 no.4
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• pp.126-134
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• 2010

Background: $CD8^+$ T cells contribute to the clearance of Hepatitis B virus (HBV) infection and an insufficient $CD8^+$ T cell response may be one of the major factors leading to chronic HBV infection. Since the HBx antigen of HBV can up-regulate cellular expression of several immunomodulatory molecules, we hypothesized that HBx expression in hepatocytes might affect $CD8^+$ T cell activity. Methods: We analyzed the activation and apoptosis of $CD8^+$ T cells co-cultured with primary hepatocytes rendered capable of expressing HBx by recombinant baculovirus infection. Results: Expression of HBx in hepatocytes induced low production of $interferon-{\gamma}$ and apoptosis of CD8+ T cells, with no effect on CD8 T cell proliferation. However, transcriptional levels of H-2K, ICAM-1 and PD-1 ligand did not correlate with HBx expression in hepatocytes. Conclusion: Our results suggest that HBx may inhibit $CD8^+$ T cell response by regulation of $interferon-{\gamma}$ production and apoptosis.

• Journal of Microbiology
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• v.45 no.5
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• pp.431-440
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• 2007

A silkworm (Bombyx mori L.) extract known to contain naturally occurring iminosugars, including 1-deoxynojirimycin (1-DNJ) derived from the mulberry tree (Morus alba L.), was evaluated in surrogate HCV and HBV in vitro assays. Antiviral activity of the silkworm extract and one of its purified constituents, 1-DNJ, was demonstrated against bovine viral diarrhea virus (BVDV) and GB virus-B (GBV-B), both members of the Flaviviridae family, and against woodchuck hepatitis virus (WHV) and hepatitis B virus (HBV), both members of the Hepadnaviridae family of viruses. The silkworm extract exhibited a 1,300 fold greater antiviral effect against BVDV in comparison to purified 1-DNJ. Glycoprotein processing of BVDV envelope proteins was disrupted upon treatment with the naturally derived components. The glycosylation of the WHV envelope proteins was affected largely by treatment with the silkworm extract than with purified 1-DNJ as well. The mechanism of action for this therapy may lie in the generation of defective particles that are unable to initiate the next cycle of infection as demonstrated by inhibition of GBV-B in vitro. We postulate that the five constituent iminosugars present in the silkworm extract contribute, in a synergistic manner, toward the antiviral effects observed for the inhibition of intact maturation of hepatitis viral particles and may complement conventional therapies. These results indicate that pre-clinical testing of the natural silkworm extract with regards to the efficacy of treatment against viral hepatitis infections can be evaluated in the respective animal models, in preparation for clinical trials in humans.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.4
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• pp.145-149
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• 2011

Serum hepatitis is still recognized as a major public health problem in many countries. The most common etiologies are acute viral hepatitis A and B, and hepatitis B virus (HBV) was known as the pathogen of serum hepatitis. since the HBV causes chronic hepatitis. HBV infection is hyperendemic in Korea. It is known that 8% and 1% of the Korean population is chronic carriers of HBV. The total number of 487 serum specimen (old people's home 190, causal ward-Daegu hope village 297) were collected at the laboratory of Department of Clinical Pathology of Daegu medical center. The laboratory tested the specimen to detect for hepatitis B surface antigen (HBsAg) and anti-HBs using reverse passive hemag-glutination (RPHA) and passive hemagglutination (PHA) method between April, 2011 and June, 2011. In one-step test, HBsAg and anti-HBs of Humasis were used. The positive rate for HBsAg was 6.80% (33/487), and the rate in male was 6.93% (19/274) higher than that of female 6.57% (14/213). In the positive rate of HBsAg by age group, the highest positive rate group was in the group of 40-49 years in male (12.0%), and 50-59 years in female (17.65 %). The overall positive rate for anti-HBs was 42.70% (208/487), showing the higher positive rate of 43.80% in male (120/274) than that of 41.30% (88/213) in female. The highest positive rate of anti-HBs in age group was the 40-49 years group in male (52.00%) and the group of under 29 in female (66.67%).

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1411-1414
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• 2014

Background: Hepatitis B and C are the leading causes of liver diseases worldwide. For hematological and solid malignancy patients undergoing chemotherapy, increases in HBV DNA and HCV RNA levels can be detected which may result in reactivation and hepatitis-related morbidity and mortality. The aim of this study was to determine the seroprevalence of Hbs ag and Anti HCV positivity in patients with solid malignancies undergoing chemotherapy and consequences during follow-up. Materials and Methods: The files of 914 patients with solid malignancies whose hepatitis markers were determined serologically at diagnosis were reviewed retrospectively. All underwent adjuvant/palliative chemotherapy. For the cases with HBV and/or HCV positivity, HBV DNA and HCV RNA levels, liver function tests at diagnosis and during follow-up and the treatment modalities that were chosen were determined. Results: Of 914 cases, Hbs Ag, anti Hbs and anti HCV positivity were detected in 40 (4.4%), 336 (36.8%) and 26 (2.8%) of the cases respectively. All of the Hbs ag positive patients received prophylactic lamuvidine before the start of chemotherapy. In the Hbs ag and anti HCV positive cases, liver failure was not detected during chemotherapy and a delay in chemotherapy courses because of hepatitis was not encountered. Conclusions: Just as with hematological malignancies, screening for HBV and HCV should also be considered for patients with solid tumors undergoing chemotherapy. Prophylactic antiviral therapy for HBV reduces both the reactivation rates and HBV related mortality and morbidity. The clinical impact of HCV infection on patients undergoing chemotherapy is still not well characterized.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.1-6
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• 2007

We describe a multiplex PCR method that can detect and differentiate simultaneously four different kinds of DNA viruses, Epstein-Barr virus (EBV), cytomegalovirus (CMV), hepatitis B virus (HBV) and parvovirus B19 (B19). Primers for the multiplex PCR reaction were designed to amplify specific regions of the EBV (pol), CMV (pol), HBV (pol) and B19 (ns) viral genomes and used to simultaneously detect individual viruses. In order to achieve optimal sensitivity and specificity for multiplex PCR, the thermo-cycling parameters, primer sequences, and concentration of each reaction components were optimized systematically. The sensitivity of the detection method ranged between 5 and 10 copies of viral genome with a mixture of multiple primer pairs. Furthermore, this highly sensitive test showed no cross-reactivity among the four viruses. Thus, the results obtained in this study provide evidence that the assay system is a good tool for supporting the diagnosis of viral infection and contamination.