• BMB Reports
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• 제38권6호
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• pp.683-689
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• 2005

Antibody to hepatitis B surface antigen (HBsAb) is the important serological marker of the hepatitis B virus (HBV) infection. Conventionally, the hepatitis B surface antigen (HBsAg) obtained from the plasma of HBV carriers is used as the diagnostic antigen for detection of HBsAb. This blood-origin antigen has some disadvantages involved in high cost, over-elaborate preparation, risk of infection, et al. In an attempt to explore the suitable recombinant HBsAg for the diagnostic purpose, the HBV S gene was expressed in Pichia pastoris and the product was applied for detection of HBsAb. Hepatitis B virus S gene was inserted into the yeast vector and the expressed product was analyzed by sodium dodecyl sulphate polyacrolamide gel electrophoresis (SDS-PAGE), immunoblot, electronic microscope and enzyme linked immunosorbent assay (ELISA). The preparations of synthesized S protein were applied to detect HBsAb by sandwich ELISA. The S gene encoding the 226 amino acid of HBsAg carrying ahexa-histidine tag at C terminus was successfully expressed in Pichia pastoris. The His-Tagged S protein in this strain was expressed at a level of about 14.5% of total cell protein. Immunoblot showed the recombinant HBsAg recognized by monoclonal HBsAb and there was no cross reaction between all proteins from the host and normal sera. HBsAb detection indicated that the sensitivity reached 10 mIu (micro international unit)/ml and the specificity was 100% with HBsAb standard of National Center for Clinical Laboratories. A total of 293 random sera were assayed using recombinant S protein and a commercial HBsAb ELISA kit (produced by blood-origin HBsAg), 35 HBsAb positive sera and 258 HBsAb negative sera were examined. The same results were obtained with two different reagents and there was no significant difference in the value of S/CO between the two reagents. The recombinant HBV S protein with good immunoreactivity and specificity was successfully expressed in Pichia pastoris. The reagent for HBsAb detection prepared by Pichia pastoris-derived S protein showed high sensitivity and specificity for detection of HBsAb standard. And a good correlation was obtained between the reagent produced by recombinant S protein and commercial kit produced by blood-origin HBsAg in random samples.

• 한국치위생학회지
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• 제9권2호
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• pp.125-136
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• 2009

The purpose of this study was to investigate the recognition of the infection routes, symptoms and treatments of HBV by students of health-related departments so as to help students learn correct knowledge about hepatitis B and provide the basic data for establishment of oral health policies to prevent hepatitis B and improve the quality of infection management. For the subjects of this study, 666 students of health-related departments and other departments of universities in Daegu City, Gyeongbuk Province were arbitrarily chosen and given a questionnaire. Then the questionnaires collected between October 1st and 31st, 2007 were analyzed. Major findings from this study are summarized below. 1. Regarding general characteristics of the subjects, 311 were students of health-related departments and 355 were students of other departments. 55.9% of the health-related department students and 49.0% of the other department students received immunization against hepatitis. 36.0% of the health-related department students and 31.6% of the other department students had antibodies. 2. Regarding the recognition of the infection routes of HBV, the right answer "Infected through placenta" was chosen by more juniors(94.4%), sophomores(93.8%) and freshmen(74.1%) of health-related departments than other students in this order (P<0.05). The answer "Infected through sexual intercourse" was chosen by the highest percentage(75.0%) of juniors followed by freshmen(69.2%) and sophomores(31.9%) (P<0.05). 3. The percentages of health-related department students who knew that "HBV can develop into hepatic cirrhosis or liver cirrhosis were the highest among juniors(88.9%), freshmen(87.7%) and sophomores(68.8%) in this order(P<0.05). Among the other department students, the percentages of right answers to the question "Acute HBV infection shows jaundice" were the highest among juniors(75.0%), sophomores(74.8%) and freshmen(58.7%)(P<0.05).

• Journal of Preventive Medicine and Public Health
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• 제21권1호
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• pp.89-98
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• 1988

While there have been not a few reports on the seroepidemiological characteristics of hepatitis B virus (HBV) infection in Korea, most of them, however, have had several limitations; operational definition of HBV infection, validity of detection methods of HBV serologic markers, size of the study population, and confirmation of the vaccination history against HBV, etc. In order to avoid such limitations, authors randomly selected 1,495 healthy adults among the 217,511 insured (target population) of Korean Medical Insurance Corporation, living in seoul, and tested HBV serologic markers by RIA method and conducted direct interview to them. Although HBV serologic markers (HBsAg, anti-HBs and anti-HBc) of all the subjects were tested, 392(26.2%) of interview failure cases and 361 vaccinee were excluded from the actual population. Finally, the serologic markers tested of 742 nonvaccinee (study population) only were analysed for the seroepidemiologic observation of the natural infection of HBV. The seroepidemiological characteristics of HBV infection in Korea were as follows ; 1. Point prevalence of HBs antigenemia was 11.7(9.1{\sim}14.3)% in male, which was slightly higher than that of female, 9.5($3.7{\sim}15.3$)%. This level was one of the highest among those of Asian-Pacific countries. Decreasing tendency of HBsAg prevalence alter the age of 50 was observed, which seems to be due to selective attrition of HBV chronic carriers among the healthy adults and/or to the limited-lasting duration of the HBs antigenemia, in part. 2. Point prevalence of anti-HBc(78.8% in male,50.9% in female) was higher than that of anti-HBs(65.2% in male,46.6% in female), respectively. And both of them were higher in male than in female. Increasing tendency of the prevalence of both antibodies was observed by age, which seems to be largely due to recurrent infection in adults and to some cumulative effect, in part, of their relatively longer-lasting duration. 3. The level of HBV infection defined by positive for at least one of the 3 serologic markers of HBV by RIA method was 84.7($81.8{\sim}87.6$)% in male and 61.2($51.9{\sim}70.5$)% in female, which was also one of the highest among those of Asian-Pacific countries. The proportion of susceptible population to HBV infection among healthy adults was 15.3% in male and 38.8% in female. 4. The relative frequency of current or past infection and chronic carrier among HBV infected person was estimated. The currently or past infected was estimated 75.7% in male and 71.8% in female, and chronic carrier state, 13.8% in male and 14.1% in female. The analysis of the geometric mean of the antibody titer in anti-HBs positive sera indicated also to be compatible with the above findings, suggesting that active, even though inapparent, infection of HBV occur so frequently among healthy adults in Korea.

• Bulletin of the Korean Chemical Society
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• 제28권10호
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• pp.1756-1762
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• 2007

Envelope proteins of virus contain a segment of hydrophobic amino acids, called as fusion peptide, which triggers membrane fusion by insertion into membrane and perturbation of lipid bilayer structure. Potential fusion peptide sequences have been identified in the middle of L or M proteins or at the N-terminus of S protein in the envelope of human hepatitis B virus (HBV). Two 16-mer peptides representing the N-terminal fusion peptide of the S protein and the internal fusion peptide in L protein were synthesized, and their membrane disrupting activities were characterized. The internal fusion peptide in L protein showed higher activity of liposome leakage and hemolysis of human red blood cells than the N-terminal fusion peptide of S protein. Also, the membrane disrupting activity of the extracellular domain of L protein significantly increased when the internal fusion peptide region was exposed to N-terminus by the treatment of V8 protease. These results indicate that the internal fusion peptide region of L protein could activate membrane fusion when it is exposed by proteolysis.

• Journal of Microbiology and Biotechnology
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• 제28권8호
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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.

• Childhood Kidney Diseases
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• 제24권1호
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• pp.36-41
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• 2020

Purpose: Hepatitis B virus (HBV) infection is among etiologies of secondary membranous nephropathy (MN) in pediatric patients. We evaluated expression of phospholipase A2 receptor (PLA2R), a specific target antigen of primary MN, in pediatric HBV-related MN. Methods: We retrospectively reviewed patients with biopsy-proven HBV-related MN from the renal biopsy registry and electronic medical records of Severance Hospital, Seoul, Korea, from 1993 to 2004. Paraffin-embedded human kidney tissues were retrieved and immunohistochemically stained for PLA2R. Results: Ten pediatric patients with 13 biopsied specimens were reviewed. The predominant pathological stage was stage II-III, and second was stage II. The intensity of staining for IgG was greatest, with less intense staining for IgM, IgA, C3, C4, and C1q. All the patients had angiotensin-converting enzyme inhibitor combined with glucocorticoid, and four patients converted to cyclosporine treatment from glucocorticoid monotherapy. Urinalysis of all the patients normalized after variable period. PLA2R staining was demonstrated in the outer glomerulus in 3 out of 13 biopsies, 2 of which were obtained from the same patient over a 5-year interval. Conclusions: PLA2R was expressed in a small number of cases diagnosed as pediatric HBV-related MN, indicating that some HBV-related MN cases may be primary MN concurrent with HBV infection.

• Journal of Preventive Medicine and Public Health
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• 제17권1호
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• pp.223-229
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• 1984

An attempt to confirm the associations of some selected risk factors of HBV infection and measure their risks, a cross-sectional study with 1,209 urban office workers was carried out. For the study, a simple questionnaire which contained several questions on personal experience and behaviors on several known selected risk factors of HBV infection was applied to each subject, and the Hepatitis B virus surface antigen and its antibody were checked by RPHA and PHA method, respectively. Risk factors chosen for this study were experience of blood transfusion and personal contact variables, such as frequencies of eating-out, drinking after office hours, going to tea room, sharing cigarettes, etc. The results obtained were as follows: 1. The proportion of HBsAg positive was 10.6%, and total HVB infected including the Anti-HBs positive cases without vaccination was 44.2%. Both were higher in male than in female. 2. Frequent personal contact through glasses and dishes in eating-outs and drinkings turned out not to be a significant risk factor of Hepatitis B surface antigenecity. 3. Frequent visits to tea room was a significant risk factor of HBV infection which combined HBsAg positive cases and Anti-HBs cases who had not received HBV vaccination. The odds ratio was 1.56 4. Blood transfusion was not a significant risk factor of both HBsAg positive and total HBV infection. In summary, indirect oral contacts through eating-outs and drinkings was not significant risk factor in Korea at least between adults. Blood transfusion is no more major source of HBV infection in Korea probably because the adquate screening test of HBsAg for the blood donors is being made.

• Pediatric Infection and Vaccine
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• 제5권1호
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• pp.96-103
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• 1998

목 적 : B형 간염 바이러스(hepatitis B virus; HBV) 보유 산모로부터 출생한 신생아의 수직감염 양상을 관찰하고 HBV 백신의 면역반응 및 방어효과를 평가하기 위하여 본 연구를 시행하였다. 대상 및 방법 : 1995년 7월부터 1996년 12월까지 18개월간 가톨릭대학교 성빈센트병원을 방문한 HBV 보유 산모와 이들로부터 분만된 신생아중 12개월간 추적관찰이 가능하였던 78례를 연구대상으로 하였다. 이들 HBV 보유 산모의 신생아에게 출생 직후부터 HBV 면역 글로불린(HBIG)과 가열 불활성화 혈장 백신을 접종한 후 4, 8, 12개월시에 검체를 채취하여 일반표지자의 양상을 면역효소법 및 방사면역법으로 측정한 후 HBV 보유 산모와 그 신생아의 각 표지자간의 관계 및 변화를 분석하였다. 결 과 : 1) 연구 대상 산모 중 HBV 보유자는 5.0%(106/2,117), HBeAg 양성 및 음성의 비율은 38.5%(37/96)와 61.5%(59/96)이었다. 2) HBV 보유 산모로부터 출생한 영아에 있어서 백신에 대한 anti-HBs 양전율은 4, 8, 12개월 시 각각 85.9%(67/78), 75.6%(59/78), 73.1%(57/78)로 유의한 차이가 있었으나(P<0.05), 산모의 HBeAg 유무와는 관련이 없었다. 형성된 anti-HBs의 기하 항체가는 4개월에 비하여 8개월, 12개월에 유의하게 증가하였다(P<0.05). HBV 백신과 HBIG 투여의 HBV 보유자 이행에 대한 12개월시의 방어 효과는 HBeAg 양성 및 음성 산모로부터 분만된 영아에서 각각 89.8%와 100%이었다. 3) 12개월의 관찰 기간동안 산모로부터 감염이 있었던 경우는 78명 중 5명으로 모두 HBeAg 양성 산모에서 분만된 영아이었고 이 중 3명에서 HBV 보유자로 이행되었다. 출생 직후 HBeAg 양성 및 음성 산모의 신생아에서 HBsAg 양성이었던 경우는 각각 4명으로 HBeAg 양성 산모의 신생아 4명 중 3명에서 감염이 발생하였다. 결 론 : 국내에서 개발된 백신의 하나인 가열 불활성화 B형 간염 혈장 백신의 항체 양전률은 85.9%이었으며, HBIG과 동시 투여하였을 때 12개월간의 HBV 보유자 이행에 대한 방어효과는 HBeAg 양성 산모에서 출생한 경우 89.8%인 반면 HBeAg 음성 산모에서 출생한 경우는 100%이었다.

• 생명과학회지
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• 제18권9호
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• pp.1207-1211
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• 2008

Pro-inflammatory cytokine인 종양괴사인자-$\alpha$ (TNF-$\alpha$)는 B형 간염바이러스(HBV) 감염에 대한 면역반응의 중요한 매개인자이다. TNF-$\alpha$의 생산은 전사수준에서 주로 조절되며, TNF-$\alpha$ promoter 다형성은 TNF-$\alpha$ 유전자 발현을 변화시키기 때문에, TNF-$\alpha$ promoter 다형성이 만성 HBV 감염의 병태생리에 영향을 미칠 가능성이 높다. 그러므로, 본 연구에서는 TNF-$\alpha$ promoter 다형성과 만성 HBV 감염의 연관성을 조사하였다. 본 연구는 만성 HBV 감염환자 181명, HBV 감염이 자연적으로 치유된 201명, 그리고 건강한 대조군 170명을 대상으로 하였다. TNF-$\alpha$ promoter의 -308G/A와 -238G/A 다형성은 PCR-RFLP법을 통하여 분석하였다. 분석결과, 환자군에서 -308과 -238 유전자형의 분포는 자연치유군 및 건강대조군에서의 분포와 통계적인 차이를 보이지 않았다(p>0.05). 또한, 그룹 간에 allele frequency도 통계적 차이가 없었다(p>0.05). 따라서, 본 연구의 결과는 한국인에서 TNF-$\alpha$ -308과 -238 promoter 다형성은 만성 B형 간염 바이러스 감염의 발생과 연관성이 없음을 시사한다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4705-4709
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• 2013

Background: Cambodian Americans have high rates of chronic hepatitis B virus (HBV) infection and liver cancer. There is very limited information about the utility of community health worker (CHW) approaches to cancer education for Asian American men. We have previously reported our positive findings from a trial of CHW education about HBV for Cambodian Americans who had never been tested for HBV. This report describes similarities and differences between the outcomes of our CHW HBV educational intervention among Cambodian American men and women. Methods: The study group for this analysis included 87 individuals (39 men and 48 women) who were randomized to the experimental (HBV education) arm of our trial, participated in the CHW educational intervention, and provided follow-up data six months post-intervention. We examined HBV testing rates at follow-up, changes in HBV-related knowledge between baseline and follow-up, and barriers to HBV testing (that were reported to CHWs) by gender. Results: At follow-up, 15% of men and 31% of women reported they had received a HBV test (p=0.09). HBV-related knowledge levels increased significantly among both men and women. With respect to HBV testing barriers, women were more likely than men to cite knowledge deficits, and men were more likely than women to cite logistic issues. Discussion: Our study findings indicate that CHW interventions can positively impact knowledge among Cambodian American men, as well as women. They also suggest CHW interventions may be less effective in promoting the use of preventive procedures by Cambodian American men than women. Future CHW research initiatives should consider contextual factors that may differ by gender and, therefore, potentially influence the relative effectiveness of CHW interventions for men versus women.