Hae-Sook Sohn

Blocking of monocyte‐associated B7‐H1 (CD274) enhances HCV‐specific T cell immunity in chronic hepatitis C infection

The establishment of a chronic hepatitis C (CHC) infection is associated with defective HCV‐specific T cell responses. Recent studies suggest that negative T cell regulators such as programmed death 1 (PD‐1) contribute to the impairment of virus‐specific T cell functions in chronic viral infections. However, the implication of peripheral monocytes from CHC patients in the inhibition of HCV‐specific T cell responses is only partially defined. In this study, we found that B7‐H1, a ligand of PD‐1, was significantly up‐regulated on monocytes of CHC patients. Proliferation of T cells in response to anti‐CD3 antibody was directly suppressed by B7‐H1+CD14+ monocytes, and this suppression was reversed by addition of antagonistic B7‐H1 mAb. Furthermore, blocking of monocyte‐associated B7‐H1 (moB7‐H1) significantly enhanced the frequency of IFN‐γ‐producing, HCV‐specific CD4+ and CD8+ effector T cells and the production of Th1 cytokines, such as IL‐2 but not Th2 cytokines, including IL‐4 and IL‐10. Upon B7‐H1 blockade, production of perforin was also increased in CD8+ T cells stimulated with HCV peptides. Our findings suggest that moB7‐H1 inhibits HCV‐specific CD4+ and CD8+ T lymphocyte proliferation and suppresses Th1 cytokine production and perforin secretion. Blockade of the B7‐H1 pathway thus represents an attractive approach in the treatment of chronic HCV infection.

The immunogenicity of a single dose of hepatitis A virus vaccines (Havrix® and Epaxal®) in Korean young adults.

Purpose Assessing the immunogenicity of a single dose of hepatitis A virus (HAV) vaccines is important because some people receive only a single dose. However, previous studies have shown variable results and have not examined the effects of demographic characteristics other than gender. This study was performed to examine the immunogenicity of a single dose of HAV vaccine according to the vaccine type and demographic characteristics in young adults. Materials and Methods Seronegative medical school students were randomly allocated to receive either Havrix or Epaxal. Results After approximately 11 months, the seroconversion rate in 451 participants was 80.7%. In men, the Havrix group showed a significantly higher seroconversion rate (81.9%) than the Epaxal group (69.2%), whereas both vaccine groups showed similarly high immunogenicity in women (Havrix: 90.1%, Epaxal: 92.9%; P for interaction=0.062). According to the results of a multivariate analysis, Epaxal showed significantly lower immunogenicity than Havrix only in men. Age, obesity, drinking, smoking, and follow-up time did not significantly affect seroconversion in either gender. Conclusion The seroconversion rate of single-dose HAV vaccines was low in men, particularly in those who received Epaxal. Our results suggest that gender effects should be considered when comparing the immunogenicity of different HAV vaccines.

Influences on Health Behaviors Execution and Self Rated Health as Socioeconomic Class by the Age Bracket

The purpose of present study was to observe the path and influencing effects between socioeconomic class (SEC), health practices and self-rated health(SRH) by the age bracket. The subjects were 4,987 adults over 25 years old who participated in the 2008 Korean National Examination Health and Nutrition Survey and could be classified into SEC in terms of the three characteristics: education, income and occupation. Path analysis was conducted with the effects of health behaviors execution on the differences in SRH, and the complex samples analysis executed by chi-square test, t-test, ANOVA. As the result, lower SRH level paralleled with the lower SEC, and more health behaviors had differed by SEC in the younger and middle aged group. The lower SEC, the lower SRH: non-smoking and weight control for younger women and exercise for aged men had indirect effects as parameters. In conclusion, when planning a health promotion program, to select the correct target populations with consideration of the age bracket, gender and SEC and to establish tailored contents fit for each of the population would be important.

Risk Factors for Hepatitis C Virus (HCV) Infection in Areas with a High Prevalence of HCV in the Republic of Korea in 2013

Background/Aims The prevalence of hepatitis C virus (HCV) infection in Busan, Gyeongnam, and Jeonnam Provinces in Korea is more than twice the national average. This study aimed to examine whether demographic and lifestyle characteristics are associated with HCV infection in these areas. Methods A case control study was performed at three study hospitals. HCV cases were matched with two controls for sex and age. Patient controls were selected from non-HCV patients at the same hospital. Healthy controls were subjects participating in medical checkups. Conditional logistic regression models were used. Results A total of 234 matched-case and patient- and healthy-control pairs were analyzed. The significant risk factors for both controls were sharing razors (adjusted odds ratio [aOR], 2.39 and 3.29, respectively) and having more than four lifetime sexual partners (aOR, 2.15 and 6.89, respectively). Contact dockworkers (aOR, 1.91) and tattoos (aOR, 2.20) were significant risk factors for the patient controls. Transfusion (aOR, 5.38), a bloody operation (aOR, 5.02), acupuncture (aOR, 2.08), and piercing (aOR, 5.95) were significant risk factors for the healthy controls. Needle stick injuries and intravenous drug abuse were significant in the univariate analysis. Conclusions More education concerning the dangers of sharing razors, tattoos and piercings is required to prevent HCV infection. More attention should be paid to needle stick injuries in hospitals and the community.

Seropositivity among Korean Young Adults Approximately 2 Years after a Single-Dose Vaccination against Hepatitis A Virus.

We previously observed 80.7% seropositivity and a significant interaction between gender and hepatitis A virus (HAV) vaccine type (Havrix vs. Epaxal) on the seropositivity approximately 11 months after single-dose HAV vaccinations in Korean young adults. Our objective was to evaluate seropositivity approximately 2 years after a single-dose HAV vaccination and the influence of demographic characteristics on seropositivity, including the interaction between gender and vaccine type. Seronegative medical school students were randomly vaccinated with Havrix or Epaxal. Based on a total serum anti-HAV antibody titer cutoff of 20 IU/mL, 338 participants (76.0%) of the 445 vaccinees were seropositive 20–25 months after a single-dose HAV vaccination. The seropositive rates were similar after vaccination with Havrix (77.0%) and Epaxal (74.9%). Univariate analysis indicated that female (p = 0.052) and less obese (p < 0.001) participants had a higher seropositive rate, whereas other characteristics such as age, alcohol use, smoking history, vaccine type, and follow-up duration were not associated with seropositivity. Multivariate analysis indicated that women (p = 0.026) and participants with moderate alcohol use (p < 0.001) showed significantly higher seropositive rates than men and participants with no or low alcohol use, respectively. The seropositive rates after vaccination with Havrix and Epaxal were 70.9% and 67.5% in men and 87.7% and 91.3% in women, respectively (p for interaction = 0.304). Compared with the seropositive rate approximately 11 months after vaccination, the seropositive rate decreased substantially only in men in the Havrix group (11.0% points), and consequently, the interaction between gender and vaccine type disappeared while seropositivity remained high (87.7% and 91.3% in Havrix and Epaxal groups, respectively) among women approximately 2 years after vaccination. Further studies are needed to assess whether the seropositive rate would be maintained in all groups more than 2 years after a single-dose HAV vaccination.

Development of a Web‐based child safety education program for Busan Safe City WHO Certification Project

As a nation that is tremendously affected by disaster- and injury-related deaths, Koreas second largest city, Busan, earnestly heeds World Health Organizations call for an international network of safe communities. As citizens of Busan dream of a safe city, officials are dedicating efforts in planning, developing and implementing sustainable programs aiming to reduce risk and promote safety awareness. The present article outlines the Busan Safe City Project and describes the development process of one of its programs, a Web-based safety education for children. Child safety remains a nationwide issue because in 2007, Korea ranked third in numbers of accident-related child deaths among the Organization for Economic Cooperation and Development countries. Future stages will involve program evaluation, revision and public release. This development process will guide other programs specific for other target populations. With everyones help, the city continues to strive to be a healthy, safe, and dynamic Busan.

Effect of Medicine Adherence on the Occurrence of Cerebrovascular Disorders in Diabetes Mellitus Patients

OBJECTIVES To assess the association between the occurrence of cerebrovascular disorders and a medication adherence in diabetes mellitus patients. METHODS Medical records from 1,114 new patients with diabetes mellitus were collected and the occurrence of cerebrovascular disorders was observed. Data was gathered from the health examination records of diabetes mellitus patients registered at the Korean Metabolic Syndrome Research from 1996 to 2005, medication records from the National Health Insurance Corporation and death data from the National Statistics Office from 1997 to 2007. Hazard ratios were analyzed using the Cox proportional hazard model to test the association between the occurrence of cerebrovascular disorders and the level of medication adherence. Medication adherence was calculated using Continuous measure of Medication Acquisition (CMA). RESULTS Of 1,114 diabetes mellitus patients, cerebrovascular disorders occurred in 67 cases (6.1%). The mean duration for the development of a cerebrovascular disorder was 3.82 yr. Medication adherence (≥0.8 vs. <0.5: HR, 3.26; 95% CI, 1.47-7.21, ≥0.8 vs. 0.5-0.7 HR, 0.99; 95% CI, 0.33-2.95) was an independent factor associated with the occurrence of cerebrovascular disorders in diabetes mellitus. CONCLUSION Increased medication adherence is necessary to prevent the occurrence of cerebrovascular disorders in diabetes mellitus patients. Furthermore we propose that CMA be considered as a method for monitoring medication adherence in clinics.

Influence of Female Undergraduates upon Sociality and College Life Satisfaction

The purpose of this study was to understand about the influence of female undergraduates health behavior and health state upon sociality and the influence of sociality upon college life satisfaction. The subjects were 335 female junior-college students with major related to public health in Busan, Daegu, and Gyeongnam and were carried out questionnaire survey on general characteristics, sociality, college life satisfaction, health behavior, health status, and internet addiction. An analytical method was made through chi-square test, t-test, one-way ANOVA, ANOVA for trend, and structural equation modeling(SEM). As a result, the influence of accountability had the greatest influence as sub-factor. Accountability and age had a positive correlation(p

Factors Associated with Failure in The Continuity of Smoking Cessation Among 6 Month's Smoking Cessation Succeses in the Smoking Cessation Clinic of Public Health Center

Abstract This study was performed to investigate the factors related failure in continuity of smoking cessation among persons who were initially successful in quitting smoking for at least 6 months in smoking cessation clinic of public health center. Data were collected with the telephone questionnaire survey and the registered cards from 347 of 6 months quitters from 2006 to 2008 year. Data were analyzed by life table method and Cox-proportional hazard model. In Cox-proportional hazard model, Eup․Myeon of residence(HR 2.50, 95% CI 1.69-3.68), without chronic diseases(HR 1.92, 95% CI 1.21-3.04), without another smoker in household(HR 1.93, 95% CI 1.21-3.09) and usage of supplement agent(HR 2.17, 95% CI 1.01-4.68) were independently associated with the failure in continuing to stay smoke-free. The cumulative rate of failure in the continuity of smoking cessation was 28.6% at 6 month and 36.1% at 24 month. For operating a clinic program for smoking cessation, Public health center should makes strategies that a person is continuing smoking cessation for over 6 months after the first 6 momths smoking cessation.