• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.815-822
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• 2001

The aim of this study is to estimate the seroconversion date of the human immunodeficiency virus(HIV) infection for the HIV infected patients in Korea. Data are collected from two cohorts. The first cohort is a group of "seroprevalent" patients who were seropositive and AIDS-free at entry. The other is a group of "seroincident" patients who were initially seronegative but later converted to HIV antibody-positive. The seroconversion dates of the seroincident cohort are available while those of the seroprevalent cohort are not. Estimation of seroconversion date is important because it can be used to calculate the incubation period of AIDS which is defined as the elapsed time between the HIV infection and the development of AIDS. In this paper, a Weibull regression model Is fitted for the seroincident cohort using information about the elapsed time since seroconversion and the CD4$^{+}$ cell count.The seroconversion dates for the seroprevalent cohort are imputed on the basis of the marker of maturity of HIV infection percent of CD4$^{+}$cell count.unt.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.1
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• pp.78-81
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• 2008

Purpose: In this study, we evaluated unstable serum data of HBe antigen (HBeAg) or HBe antibody (HBeAb) in patients who experienced HBeAg seroconversion. This study have been performed to assist a medical technologist in the recognition of patients who were chronically infected with the hepatitis B virus (HBV). Materials and Methods: A total number of 3 patients were enrolled in this study. All patients experienced HBeAg seroconversion. Serum data of HBeAg and HBeAb were measured by radioimmunoassay. Results: The data of HBeAg or HBeAb showed an unstable change during seroconversion from HBeAg to HBeAb in chronic type B hepatitis (CBH). Conclusions: Serum data of HBeAg or HBeAb can change during HBe seroconversion. These data suggest that patients with HBe seroconversion can experience an unstable oscillation of HBeAg or HBeAb value from positive to negative. Unstable data can appear naturally due to the seroconversion process.

• The Journal of Korean Medicine
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• v.27 no.4
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• pp.209-214
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• 2006

Objective : Report on a hepatitis B patient with abnormal AST/ALT, HBeAg(+), and habitual diarrhea stemming from irritable colon. Methods : Lab-evaluation of intervals of herb medicine treatment for a patient with hepatitis B with HBeAg and irritable colon. Result & Conclusion : AST/ALT level was normalized and did not rise again. Seroconversion to HBeAb repeatedly appeared just druing the time of the treatment, but typically repeated seroconversion between treatment period and no treatment period confirmed that the treatment was effective for the immune system against hepatitis B. The exact mechanism is not clear but the result provides an indication that oriental herbal medicine has potential capacity to treat liver diseases.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.16 no.2
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• pp.80-88
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• 2013

Purpose: To identify the predictive factors of long-term therapeutic response or resistance to lamivudine treatment in children and adolescents with chronic hepatitis B. Methods: Eighty one children and adolescents with chronic hepatitis B were included, who received lamivudine treatment for at least 6 months. Their condition was monitored for at least 12 months (12-88 months) thereafter. Twenty one (25.9%) were preschool children ($age{\leq}6$). For patients who had developed HBeAg seroconversion or breakthrough, univariate and multivariate analyses were used to identify the effects of age, gender, pretreatment alanine aminotransferase (ALT) and hepatitis B virus DNA levels. Results: HBeAg seroconversion occurred in 49 (60.5%) of the 81 patients after the initiation of the lamivudine therapy. In 65 patients whom were monitored for over 24 months, the seroconversion rate was significantly higher in younger patients (p=0.040), especially in those patients of preschool age ($age{\leq}6$, p=0.031). The seroconversion rate was significantly higher in higher pretreatment ALT (p=0.003). The breakthrough occurred in 21 (25.9%) of the 81. The breakthrough rate was lower in younger aged patients ($age{\leq}6$), and with higher pretreatment ALT levels, but no significant difference. Conclusion: Younger age is a good predictor of HBeAg seroconversion in children with long-term lamivudine treatment as well as high pretreatment ALT levels.

• Journal of Korean Biological Nursing Science
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• v.16 no.1
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• pp.26-32
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• 2014

Purpose: Needlestick injuries (NSI) is the most frequent occupational hazard for healthcare personnel (HCP), and immediate report and adequate post-exposure prophylaxis (PEP) is essential in preventing occupational transmission of blood-borne pathogens. Methods: From June 2010 to October 2010, 544 NSI were reported through websites from 21 general hospitals in Korea. Among those, 499 cases of NSI were analyzed to identify the rate of follow-up treatment completion and for seroconversion. Results: 88.2% of the cases were completed with follow-up treatment, 8.8% of the NSI were not completed with follow-up treatment, and 5 cases were unavailable to trace. 4.2% cases of NSI required a hepatitis B vaccination concurrent with hepatitis B immunoglobulin. 41.1% of the cases and 31.1% of the cases needed to be tested for anti HCV and anti HIV, respectively. Prophylaxis medication for HIV was prescribed in 3 cases, and all cases completed required 1 month of medication. There was 1 case (0.2%) of seroconversion to HCV. Conclusion: The PEP completion rate was not satisfactory, and the importance of completion of PEP treatment should be emphasized through education and counseling. Also, a careful risk assessment is needed for HCP who are exposed to HCV or HIV.

• Clinical and Experimental Pediatrics
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• v.50 no.9
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• pp.823-834
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• 2007

Interferon (IFN) alpha has been the first line therapy of chronic hepatitis B in children, but HBeAg seroconversion occurred in 26% of treated children compared to 11% of controls in multinational randomized controlled study. Recently, lamivudine was shown to be a potent inhibitor of Hepatitis B virus (HBV) reproduction both in HBeAg positive and in HBeAg negative (the pre-core mutant form) chronic hepatitis in randomized studies worldwide. Lamivudine therapy led to considerable improvement in the seroconversion rate of HBeAg in children with chronic hepatitis B, though long-term therapy resulted in the expansion of lamivudine-resistant mutant viruses. Combination therapy with lamivudine plus alpha-IFN does not seem to improve HBe Ag seroconversion. Above all, the most effective way to prevent hepatitis B is universal HBV vaccination.

• The Journal of Korean Society of Virology
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• v.30 no.1
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• pp.11-18
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• 2000

Since $Hantavax^{TM}$, formalin inactivated Hantaan virus vaccine (10,240 ELISA units/ml), has been developed in 1990 to prevent against haemorrhagic fever with renal syndrome (HFRS) caused by Hantaan or Seoul virus, it has been commercially available in Korea. Twenty-one healthy people were booster shot once and twice after primary basic vaccination with $Hantavax^{TM}$. Seroconversion rates were measured by immunofluorescent antibody technique (IFAT), enzyme-linked immunosorbent assay (ELISA), high density composite particle agglutination (HDPA), and plaque reduction neutralization test (PRNT). Seroconversion rates of 21 vaccinees at one year after primary basic vaccination were 52.3%, 95.2%, 0.0%, 47.6%, and 28.6%, and 13 vaccinees at one month after 1st booster vaccination were 100%, 100%, 30.7%, 100% and 100% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Seroconversion rates declined slightly by twenty months, and they were 84.6%, 92.3%, 0.0%, 84.6% and 69.2% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Seroconversion rates of 9 vaccinees at three months after 2nd booster vaccination were 100%, 100%, 0.0%, 100%, and 88.9%, and 16 vaccinees at one year after the 2nd booster vaccination were 87.5%, 93.8%, 0.0%, 87.5% and 81.3% by IFAT, ELISA (IgG, IgM), HDPA and PRNT, respectively. Based on the above result $Hantavax^{TM}$ has proved a vigorous anamnestic response after the 1st and the 2nd booster vaccination and has persisted higher fluorescence, agglutination and neutralizing antibody titers in vaccinees.

• The Journal of Internal Korean Medicine
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• v.37 no.3
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• pp.529-538
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• 2016

Objectives: The purpose of this case study is to report the efficacy and safety of treatment with Korean medicine of a patient with HBeAg-positive chronic viral hepatitis B.Methods: The patient took Korean medicine (mainly Injinchunggan-tang-gamibang) from July 20th, 2010, to March 14th, 2016, without any antiviral or interferon therapy. Changes to laboratory records, abdomen ultrasonography, and clinical symptoms were reviewed.Results: The laboratory records showed that AST, ALT, and HBV DNA had decreased to normal ranges, and HBeAg showed seroconversion. Clinical symptoms also improved after taking Korean medicine.Conclusion: The results suggest that treatment with Korean medicine and without antiviral or interferon therapy could be effective for HBeAg-positive chronic hepatitis B.

• Korean Journal of Clinical Laboratory Science
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• v.46 no.1
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• pp.17-21
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• 2014

The prevalence of hepatitis A virus (HAV) in a certain community reflects that community's living standard and hygienic condition. The seroprevalence rate of IgG anti-HAV has been changing with regions and times. In this study, we aimed to study the difference of seroprevalence of IgG anti-HAV according to sex, age and type of drinking water, and to know the vaccination rate and seroconversion rate for vaccinated subjects in Busan. A total of 644 samples were analyzed. The overall seroprevalence rate of IgG anti-HAV was 35.4% (228/644). There was no significant difference in sex (male 39.8%, female 32.7) (p>0.05). According to age, seroprevalence rate of anti-HAV were 55.0% in subjects aged 5~9 years old, 47.8% in 10~14 years old, decreced to 10.6% in 15~19 years old, 1.0% in 20~24 years old, 0.0% in 25~29 years old and increced with advacing ages ; 14.7% in 30~34 years old, 39.4% in 35~39 years old, 67.3% in 40~44 years old, 94.1% in 45~49 years old, 100.0% over 50 years (p<0.001). The seroprevalence of IgG anti-HAV was no statistical difference according to the types of drinking water (p>0.05). The vaccinated subject was 42 case only in below 25 years old. The seroconversion rate after vaccination was 88.1%.

• Pediatric Infection and Vaccine
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• v.5 no.2
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• pp.245-257
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• 1998

Purpose : Although hepatitis B vaccine has been available to general population in Korea since 1983, it was difficult to compare various types of hepatitis B virus(HBV) vaccines primarily due to the differences in vaccination schedule, dosage, test methods and seropositive antibody level. In this study we reviewed the results of previous studies published in Korea, which include antibody positive rates and antibody titers of various vaccines, and examined the immunogenicity of these HBV vaccines. Methods : Studies published in medical journals, university journals concerning antibody positive rates following hepatitis B vaccination were reviewed. Inclusion criteria were those studies in which seroprotective antibody rate of 10mIU/mL or the sample ratio unit of 10 RU were used as the cut-off value and in which the test methods were RIA or ELISA. Exclusion criteria were; 1) unclear or inconsistent vaccine dosage, 2) no record of antibody titers or seroconversion rate, 3) no defined antibody rate or ratio for positive rating and 4) the vaccination schedule other than 0-1-2 months or 0-1-6 months. Results : 23 out of 52 studies were subjected for the review for seroconversion rates. 1) As for the immunogenicity in each age group, the seroconversion rates of Hepaccine(Cheil Jedang) were 85.1% in infants, 83.3% in children and 62.7% in adults, indicating higher rates in infants and children compared to adults(P<0.01). The seroconversion rates of Hepavax(Korea Green Cross) were 84.7%, 81.1% and 90.8%, indicating higher rates in infants and adults compared to children(P<0.01). 2) The seroconversion rate of Hepavax was 85.6% with 0-1-6 mo. schedule, 78.5% with 0-1-2 mo. schedule with a statistically significant difference(P<0.01). 4) There was no difference of seroconversion rates between the two doses of Hepavax, $5{\mu}g$ and $10{\mu}g$ in infants and children. 5) In adults the seroconversion rates were 62.7% with Hepaccine, 90.8% with Hepavax, and 94.8% with Engerix-B(SmithKline Beecham). Conclusion : In Korea, the incidence of chronic hepatitis B is high and changing the schedule in vaccination cannot contribute to the increase of the serocoversion rate. And in order to maximize immunogenicity, more effective vaccines as well as more proper vaccination methods should be used.