• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3555-3559
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• 2013

Chronic hepatitis B virus (HBV) infection and dietary exposure to aflatoxin B1 (AFB1) are major risk factors for hepatocellular carcinoma (HCC). The aim of this study was to evaluate the role of HBV genetic variation and the R249S mutation of the p53 gene, a marker of AFB1-induced HCC, in Thai patients chronically infected with HBV. Sixty-five patients with and 89 patients without HCC were included. Viral mutations and R249S mutation were characterized by direct sequencing and restriction fragment length polymorphism (RFLP) in serum samples, respectively. The prevalences of T1753C/A/G and A1762T/G1764A mutations in the basal core promotor (BCP) region were significantly higher in the HCC group compared to the non-HCC group. R249S mutation was detected in 6.2% and 3.4% of the HCC and non-HCC groups, respectively, which was not significantly different. By multiple logistic regression analysis, the presence of A1762T/G1764A mutations was independently associated with the risk of HCC in Thai patients.

• Molecules and Cells
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• v.42 no.1
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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.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.35-39
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• 2015

Background: Hepatocellular carcinoma (HCC) is one of the most frequent cancers in South East Asian countries including Cambodia, where prevalence of chronic carriers of hepatitis B and C virus (HBV and HCV) is reported to be very high. We reviewed HCC cases admitted to a cancer hospital in Phnom Penh, which is the only one hospital for cancer treatment and care in Cambodia during the study period. Materials and Methods: Information was collected from medical records of 281 cases (210 males and 71 females) diagnosed as primary HCC from 2006 to 2011. Results: The subjects were 7-81 years old with a median age of 53 years. Hypochondriac pain was the most common complained symptom (74%). One third of the cases presented with jaundice. Nearly half had ascites at their first visit. One third had liver cirrhosis. Nearly three fourths of the cases presented with tumor sized more than 50 mm in diameter, and in almost all cases (97.4%) the size was more than 20 mm. Among 209 subjects tested, hepatitis virus carriers were 75.6%; 46.4% for HBV only, 21.5% for HCV only, and 7.7% for both viral infections. Median age of patients with HBV was about ten years younger than those with HCV. Conclusions: This study revealed the characteristics of HCC cases in Cambodia, although there were several limitations. Most HCC cases were infected with HBV and/or HCV, and diagnosed at late stages with complications. This implicated that public health intervention to prevent HBV and HCV infection is of high priority.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3479-3483
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• 2015

Objective: Patients with hepatocellular carcinoma (HCC) in stage Barcelona Clinic Liver Cancer (BCLC)-A were grouped based on whether they were accompanied with hepatitis B virus (HBV) infection or not so as to explore the clinical characteristics and prognostic conditions of HCC patients with non-HBV/hepatitis C virus (HCV). Materials and Methods: Clinical data of 64 stage BCLC-A HCC patients with non-HBV/HCV infection (observation group) who received radical hepatectomy in the Affiliated Cancer Hospital of Guangxi Medical University from January, 2006 to November, 2014 were retrospectively analyzed and compared with those of 409 stage BCLC-A HCC patients with HBV infection (control group) in corresponding period. Results: The postoperative 1-, 3- and 5-year recurrent rates of the observation group were 25%, 38.6% and 48.8%, with postoperative mean and median disease-free survival time being 49.1 months and 62.0 months, respectively. Additionally, the postoperative 1-, 3- and 5-year survival rates of observation group were 90.1%, 72.7% and 62.0%, with the mean and median survival times being 54.4 months and 70.0 months, respectively. Conclusions: The 1-year recurrent rate is the highest in HCC patients with non-HBV/HCV, and almost half of the patients have recurrence within 1 year, after which the recurrent rate decreases along with the time.

• Annals of Laboratory Medicine
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• v.38 no.6
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• pp.578-584
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• 2018

Background: Accurate, rapid, and cost-effective screening tests for hepatitis B virus (HBV) and hepatitis C virus (HCV) infection may be useful in laboratories that cannot afford automated chemiluminescent immunoassays (CLIAs). We evaluated the diagnostic performance of a novel rapid automated fluorescent lateral flow immunoassay (LFIA). Methods: A fluorescent LFIA using a small bench-top fluorescence reader, Automated Fluorescent Immunoassay System (AFIAS; Boditech Med Inc., Chuncheon, Korea), was developed for qualitative detection of hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), and antibody to HCV (anti-HCV) within 20 minutes. We compared the diagnostic performance of AFIAS with that of automated CLIAs-Elecsys (Roche Diagnostics GmbH, Penzberg, Germany) and ARCHITECT (Abbott Laboratories, Abbott Park, IL, USA)-using 20 seroconversion panels and 3,500 clinical serum samples. Results: Evaluation with the seroconversion panels demonstrated that AFIAS had adequate sensitivity for HBsAg and anti-HCV detection. From the clinical samples, AFIAS sensitivity and specificity were 99.8% and 99.3% for the HBsAg test, 100.0% and 100.0% for the anti-HBs test, and 98.8% and 99.1% for the anti-HCV test, respectively. Its agreement rates with the Elecsys HBsAg, anti-HBs, and anti-HCV detection assays were 99.4%, 100.0%, and 99.0%, respectively. AFIAS detected all samples with HBsAg genotypes A-F and H and anti-HCV genotypes 1, 1a, 1b, 2a, 2b, 4, and 6. Cross-reactivity with other infections was not observed. Conclusions: The AFIAS HBsAg, anti-HBs, and anti-HCV tests demonstrated diagnostic performance equivalent to current automated CLIAs. AFIAS could be used for a large-scale HBV or HCV screening in low-resource laboratories or low-to middle-income areas.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.3
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• pp.261-266
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• 2018

To determine the clinical utility of an immunoblot test and RT-PCR-hybridization test, 160 samples from patients with a chronic HCV infection were analyzed by two tests. A total of 133 samples out of 150 positive samples were positive by RT-PCR-hybridization. The true positive rate of the immunoblot tests and the concordance rate of the two tests was 88.6% and 89.3%, respectively. Serotyping and genotyping were performed to evaluate the distribution of the HCV subtype in Korean isolates. HCV serotypes 1 and 2, and genotypes 1b and 2a were the most common sources of HCV infections in this group. In 49 cases studied with the serotypes and genotypes, serotypes 1 and 2 were 57.1% and 42.9%, respectively. Genotypes 1b, 1b/2b, 2a, 2a/2c, and 2b were 51.0%, 2.0%, 34.7%, 8.2%, and 4.1%, respectively. This study shows that immunoblot tests are more useful for screening HCV infections. The RT-PCR-hybridization test confirmed the HCV infection in patients with positive immunoblot test results. The serotype test is preferred over the genotype test for monitoring the progression or response to treatment. On the other hand, there were no significant differences in the response to an ${\alpha}$-interferon treatment of HCV infection with serotype type 1 or type 2 in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.4953-4960
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• 2013

Primary liver cancer is one of the most common cancers at the global level, accounting for half of all cancers in some undeveloped countries. This disease tends to occur in livers damaged through alcohol abuse, or chronic infection with hepatitis B and C, on a background of cirrhosis. Various cancer-causing substances are associated with primary liver cancer, including certain pesticides and such chemicals as vinyl chloride and arsenic. The strong association between HBV infection and liver cancer is well documented in epidemiological studies. It is generally acknowledged that the virus is involved through long term chronic infection, frequently associated with cirrhosis, suggesting a nonspecific mechanism triggered by the immune response. Chronic inflammation of liver, continuous cell death, abnormal cell growth, would increase the occurrence rate of genetic alterations and risk of disease. However, the statistics indicated that only about one fifth of HBV carries would develop HCC in lifetime, suggesting that individual variation in genome would also influence the susceptibility of HCC. The goal of this review is to highlight present level of knowledge on the role of viral infection and genetic variation in the development of liver cancer.

• Journal of dental hygiene science
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• v.22 no.2
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• pp.108-114
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• 2022

Background: Students in the department of dental hygiene are exposed to injections and sharp instruments during clinical practice. Therefore, it is necessary to develop measures for a safe practice environment. This study aimed to investigate dental stabbing accidents caused by dental instruments during clinical practice among students in the department of dental hygiene and suggest appropriate preventative measures. Methods: This study was conducted from May 1 to June 30, 2016, with students in the department of dental hygiene located at several universities in Seoul and Gyeonggi area. The study included 339 participants. A frequency analysis was performed to determine the general characteristics of dental infection control. A cross-analysis was conducted to identify the relationship between dental infection control education, stabbing accident prevention education, and treatment after stabbing accidents with a dental instrument. Results: Among the participants, 81.1% received dental infection control education and 66.4% received stabbing accident prevention education. Only 50.9% received hepatitis B vaccinations. Conclusion: Dental infection control education and stabbing accident prevention education were shown to be effective in preventing dental instrument stabbing in students. However, post-accident processing, such as reporting to upper management and medical treatment after the accident, was insufficient. Therefore, it is necessary to present a treatment flowchart for dealing with stab accidents in clinical practice for students in the department of dental hygiene and strengthen education.

• Pediatric Infection and Vaccine
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• v.4 no.1
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• pp.106-115
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• 1997

Objective : To evaluate the immunogenicity and safety afforded by the HG-II$^{(R)}$ recombinant hepatitis B vaccine given to healthy neonates and children and to find the influence of preceding BCG vaccination on immunogenicity. Methods : Three doses of recombinant hepatitis B vaccine with a dose of $10{\mu}g$ were given at birth, 1 and 6 months of age. This study was conducted in three hospitals (Gyeongsang National University Hospital(Group A), Kangnam General Hospital(Group B) and Younsei University Hospital(Group C)) from April, 1995 to June, 1996. Group A and Group B received 2nd dose of hepatitis B vaccine at 1 week after and before BCG vaccine, respectively. Antibidy levels, at 1 month after the 3rd dose of hepatitis B vaccine were determined by a radioimmunoassay. Results : 1) One hundred four infants and ten children were enrolled : 55 infants and 43 infants received 2nd dose of hepatitis B vaccine at 1 week after( After BCG Group) and before BCG vaccine(Before BCG Group), respectively. 2) The seropositive rate was 99.1%, and geometric mean anti-HBs titer was 131.2mIU/ml. 3) The geometric mean titers were 105.5mIU/ml and 162.8mIU/ml in After BCG and Before BCG Group, respectively(p<0.025). 4) Among 359 episodes of vaccination, the occurrence of systemic and local side reaction were reported in 7.8% and 1.4%, respectively. Conclusion : Recombinant hepatitis B vaccine(HG-II$^{(R)}$))was highly immunogenic and safe. The significantly lower geometric mean antibody titer in the BCG preceding group was observed. Well-designed controlled study with the large number of sample size will be required to show the influence of preceding BCG vaccination.

• Journal of Microbiology and Biotechnology
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• v.29 no.7
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• pp.1137-1143
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• 2019

Hepatitis E virus (HEV) accounts for 20 million infections in humans worldwide. In most cases, the infections are self-limiting while HEV genotype 1 infection cases may lead to lethal infections in pregnant women (~ 20% fatality). The lack of small animal models has hampered detailed analysis of virus-host interactions and HEV-induced pathology. Here, by employing a recently developed culture-adapted HEV, we demonstrated that methyltransferase, a non-structural protein, strongly inhibits melanoma differentiation-associated gene 5 (MDA5)-mediated activation of type I interferon responses. Compared to uninfected controls, HEV-infected cells display significantly lower levels of $IFN-{\beta}$ promoter activation when assessed by luciferase assay and RT-PCR. HEV genome-wide screening showed that HEV-encoded methyltransferase (MeT) strongly inhibits MDA5-mediated transcriptional activation of $IFN-{\beta}$ and $NF-{\kappa}B$ in a dose-responsive manner whether or not it is expressed in the presence/absence of a tag fused to it. Taken together, current studies clearly demonstrated that HEV MeT is a novel antagonist of MDA5-mediated induction of $IFN-{\beta}$ signaling.