• 미생물학회지
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• 제45권4호
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• pp.346-353
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• 2009

이식을 위해 사용하는 사람 양막은 기증자로부터 수혜자에게 바이러스, 세균, 진균과 같은 감염성 위해인자를 전파할 위험이 있다. 따라서 적절한 소독 및 멸균 공정을 통해 이식용 양막 내재 또는 혼입 가능한 감염성 위해인자를 완벽하게 불활화하여야 한다. 본 연구에서는 인체조직은행에서 사용하고 있는 소독 공정과 멸균 공정의 바이러스 및 세균, 진균 불활화 효과를 검증하기 위해 국제적 가이드에 따라 5종의 바이러스[human immunodeficiency virus type 1 (HIV-1), bovine herpes virus (BHV), bovine viral diarrhoea virus (BVDV), hepatitis A virus (HAV), porcine parvovirus (PPV)]와 2종의 세균(Escherichia coli, Bacillus subtilis), 1종의 진균(Candida albicans)을 생물학적 지표로 사용하였다. 양막에 각 생물학적 지표를 첨가한 후 70% 에탄올 소독 공정, 감마선 조사 공정, 산화에틸렌 가스 멸균 공정을 실시한 다음 각 바이러스, 세균, 진균을 회수하여 정량한 후 불활화 정도를 비교하였다. 70% 에탄올 처리 공정에서 HIV-1, BHV, BVDV 같은 외피 바이러스는 처리 시간 2.5분 안에 불활화되었지만, HAV와 PPV 같은 비-외피 바이러스는 에탄올에 매우 큰 저항성을 나타내었다. 감마선 2.5 kGy 조사에 의해 HIV-1, BHV, BVDV는 검출한계 이하로 완벽하게 불활화되었다. HAV와 PPV는 각각 5 kGy와 25 kGy 조사에 의해 검출한계 이하로 불활화되었다. 산화에틸렌 가스 처리에 의해 본 연구에 사용한 모든 바이러스가 검출한계 이하로 불활화되었다. 70% 에탄올 처리 공정에서 E. coli와 C. albicans는 모두 5분 안에 완벽하게 사멸하였다. 하지만 B. subtilis는 큰 저항성을 나타내었다. 감마선 조사 공정과 산화에틸렌 가스 멸균 공정에서 E. coli, B. subtilis, C. albicans 모두 완벽하게 불활화되었다.

• 대한수의학회지
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• 제60권2호
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• pp.61-68
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• 2020

The zoonotic transmission of viral diseases to humans is a serious public health concern. Pigs are frequently a major reservoir for several zoonotic viral diseases. Therefore, periodic surveillance is needed to determine the infection rates of zoonotic diseases in domestic pigs. Hepatitis E virus (HEV), rotavirus, sapovirus (SaV), and norovirus (NoV) are potential zoonotic viruses. In this study, 296 fecal samples were collected from weaned piglets and growing pigs in 13 swine farms, and the viral RNA was extracted. Partial viral genomes were amplified by reverse transcription-polymerase chain reaction (PCR) or nested-PCR using virus-specific primer sets under different PCR conditions. HEV-3, rotavirus A, and SaV genogoup 3 were detected from 11.5, 2.7, and 3.0% of the samples, respectively. On the other hand, NoV was not detected in any of the samples. Genetic analysis indicated that the nucleotide sequences of swine HEV-3 and rotavirus A detected in this study were closely related to those of human isolates. However, swine SaV was distant from the human strains. These results suggest that HEV-3 and rotavirus A can be transmitted from pigs to humans. Therefore, strict preventive measures should be implemented by workers in the swine industry to prevent infections with HEV-3 and rotavirus A excreted from pigs.

• IMMUNE NETWORK
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• 제5권1호
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• pp.1-10
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• 2005

Background: Chronic infection with hepatitis B virus (HBV) affects about 350 million people worldwide, which have a high risk of development of cirrhosis and hepatocellular carcinoma. Treatment of chronic HBV infection relies on IFN-${\alpha}$ or lamivudine. However, interferon-${\alpha}$ is effective in only about 30% of patients. Also, the occurrence of escape mutations limits the usage of lamivudine. Therefore, the development and evaluation of new compounds or approaches are urgent. Methods: We comparatively evaluated DNA and adenoviral vaccines expressing HBV antigens, either alone or in combined regimens, for their ability to elicit Th1-type immune responses in Balb / c mice which are believed to be suited to resolve HBV infection. The vaccines were tested with or without a genetically engineered IL-12 (mIL-12 N220L) which was shown to enhance sustained Th1-type immune responses in HCV E2 DNA vaccine. Results: Considering the Th1-type cytokine secretion and the IgG2a titers, the strongest Th1-type immune response was elicited by the DNA prime-adenovirus boost regimen in the presence of mIL-12 N220L. In addition, the codelivery of mIL-12 N220L modulated differentially the immune responses by different vaccination regimens. Conclusion: Our results suggest that the DNA prime-adenovirus boost regimen in the presence of mIL-12 N220L may be the best candidate for HBV vaccine therapy of the regimens tested in this study and will be worthwhile being evaluated in chronic HBV patients.

• Molecules and Cells
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• 제44권9호
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• pp.688-695
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• 2021

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a global health concern. Various SARS-CoV-2 vaccines have been developed and are being used for vaccination worldwide. However, no therapeutic agents against coronavirus disease 2019 (COVID-19) have been developed so far; therefore, new therapeutic agents are urgently needed. In the present study, we evaluated several hepatitis C virus direct-acting antivirals as potential candidates for drug repurposing against COVID-19. Theses include asunaprevir (a protease inhibitor), daclatasvir (an NS5A inhibitor), and sofosbuvir (an RNA polymerase inhibitor). We found that asunaprevir, but not sofosbuvir and daclatasvir, markedly inhibited SARS-CoV-2-induced cytopathic effects in Vero E6 cells. Both RNA and protein levels of SARS-CoV-2 were significantly decreased by treatment with asunaprevir. Moreover, asunaprevir profoundly decreased virion release from SARS-CoV-2-infected cells. A pseudoparticle entry assay revealed that asunaprevir blocked SARS-CoV-2 infection at the binding step of the viral life cycle. Furthermore, asunaprevir inhibited SARS-CoV-2 propagation in human lung Calu-3 cells. Collectively, we found that asunaprevir displays broad-spectrum antiviral activity and therefore might be worth developing as a new drug repurposing candidate for COVID-19.

• IMMUNE NETWORK
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• 제21권5호
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• pp.37.1-37.17
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• 2021

Hepatitis B virus X (HBx) protein has been reported as a key protein regulating the pathogenesis of HBV-induced hepatocellular carcinoma (HCC). Recent evidence has shown that HBx is implicated in the activation of autophagy in hepatic cells. Nevertheless, the precise molecular and cellular mechanism by which HBx induces autophagy is still controversial. Herein, we investigated the molecular and cellular mechanism by which HBx is involved in the TRAF6-BECN1-Bcl-2 signaling for the regulation of autophagy in response to TLR4 stimulation, therefore influencing the HCC progression. HBx interacts with BECN1 (Beclin 1) and inhibits the association of the BECN1-Bcl-2 complex, which is known to prevent the assembly of the pre-autophagosomal structure. Furthermore, HBx enhances the interaction between VPS34 and TRAF6-BECN1 complex, increases the ubiquitination of BECN1, and subsequently enhances autophagy induction in response to LPS stimulation. To verify the functional role of HBx in liver cancer progression, we utilized different HCC cell lines, HepG2, SK-Hep-1, and SNU-761. HBx-expressing HepG2 cells exhibited enhanced cell migration, invasion, and cell mobility in response to LPS stimulation compared to those of control HepG2 cells. These results were consistently observed in HBx-expressed SK-Hep-1 and HBx-expressed SNU-761 cells. Taken together, our findings suggest that HBx positively regulates the induction of autophagy through the inhibition of the BECN1-Bcl-2 complex and enhancement of the TRAF6-BECN1-VPS34 complex, leading to enhance liver cancer migration and invasion.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3131-3138
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• 2016

Several studies have addressed the possible role of hepatitis C virus genotype-4 (HCV GT4) in apoptosis. However, this still not fully understood. In the current study a re-constructed clone of E1/E2 polyprotein region of the HCV GT4 was transfected into the Huh7 cell line and a human apoptotic PCR array of 84 genes was used to investigate its possible significance for apoptosis. Out of the 84 genes, only 35 showed significant differential expression, 12 genes being up-regulated and 23 down-regulated. The highest-up regulated genes were APAF1 (apoptotic peptidase-activating factor 1), BID (BH3 interacting domain death agonist) and BCL 10 (B-cell CLL/lymphoma protein 10) with fold regulation of 33.2, 30.1 and 18.9, respectively. The most down-regulated were FAS (TNF receptor super family), TNFRSF10B (tumor necrosis factor receptor super-family member 10b) and FADD (FAS-associated death domain) with fold regulation of -30.2, -27.7 and -14.9, respectively. These results suggest that the E1/E2 proteins may be involved in HCV-induced pathogenesis by modulating apoptosis through the induction of the intrinsic apoptosis pathway and disruption of the BCL2 gene family.

• 대한임상검사과학회지
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• 제43권2호
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• pp.57-67
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• 2011

In this study, we investigated the correlation between the administration of various antiviral agents and the alternation of specific biomarkers induced by the hepatitis B virus (HBV). Eligible subjects diagnosed with chronic hepatitis B were prescribed with antiviral drugs at the Gastroenterology Internal Medicine Department of E University Hospital in Daejeon between May 2004 and September 2009. Lamivudine was prescribed to 66 out of 100 patients. Of the 12 patients, 6 (50.0%) showed a change from being HBe-antigen-positive to being HBe-antigen-negative. Of the 39 patients, 23 (59.0%) showed higher than 40 IU/L alanine aminotransferase (ALT). Of the 65 patients, 41 (63.1%) showed HBV DNA decrease of 1 log, and were prescribed with Lamivudine. Adefovir was prescribed to 3 out of 100 patients. Of the 12 patients, 1 (8.3%) showed a change from being HBe-antigen-positive to being HBe-antigen-negative, and was prescribed with Adefovir. Entecavir was prescribed to 19 (19.0%) out of 100 patients. Of the 12 patients, 3 (25.0%) showed a change from being HBe-antigen-positive to being HBe-antigen-negative. Of the 12 patients, 3 (125.8%) showed higher than 40 IU/L ALT. Of the 65 patients, 14 (21.5%) showed HBV DNA decrease of 1 log, and were prescribed with Entecavir. Clavudine was prescribed to 7 out of 100 patients. Of the 12 patients, 1 (8.3%) showed a change from positive HBe antigen to negative HBe antigen. Of the 39 patients, 5 (12.8%) showed higher than 40 IU/L ALT. Of the 65 patients, 6 (9.2%) showed HBV decrease of 1 log, and were prescribed with Clavudine. These results do not show a statistically significant correlation between drugs and biomarkers. Data on combination therapy using Lamivudine and Adefovir show no statistically significant difference between drugs and biomarkers. Medications for periodic inspection was not correlated to HBe-antigen-negative conversion, ALT, and HBV DNA. HBV DNA was significantly reduced in patients with high levels of AST(aspartic acid aminotransferase) and ALT before treatment. In addition, the decrease of HBV DNA after 12 months of treatment was less frequently observed in patients treated with Lamivudine compared with other drugs. This result is associated with Lamivudine resistance. Although the association of drugs with diagnostic markers and the correct choice of treatment is difficult to determine, these results may be useful for further research on diagnosis and treatment of the hepatitis B virus.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.178-178
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• 1994

Hepatitis B Virus (HBV) is a DNA virus with a 3.2kb partially double-stranded genome. The life cycle of the virus involves a reverse transcription of the greater than genome length 3.5kb mRNA. This pegenomic RNA contains all the genetic information encoded by the virus and functions as an intermediate in viral replication. Tumor suppressor p53 has previously been shown to interact with the X-gene product of the HBV, which led us to hypothesize that p53 may act as a negative regulator of HBV replication and the role of the X-gene product is to overcome the p53-mediated restriction. As a first step to prove the above hypothesis, we tested whether p53 represses the propagation of HBV in in vitro replication system. By transient cotransfection of the plasmid containing a complete copy of the HBV genome and/or the plasmid encoding p53, we found that the replication of HBV is specifically blocked by wild-type p53. The levels of HBV DNA, HBs Ag and HBc/e Ag secreted in cell culture media were dramatically reduced upon coexpresion of wild-type p53 but not by the coexpression of the mutants of p53 (G154V and R273L). Furthermore, levels of RNAs originated from HBV genome were repressed more than 10 fold by the cotransfection of the p53 encoding plasmid. These results clearly states that p53 is a nesative regulator of the HBV replication. Next, to addresss the mechanism by which p53 represses the HBV replication, we performed the transient transfection experiments employing the pregenomic/core promoter-CAT(Chloramphenicol Acetyl Transferase) construct as a reporter. Cotransfection of wild-type p53 but not the mutant p53 expression plasmids repressed the CAT activity more than 8 fold. Integrating the above results, we propose that p53 represses the replication of HBV specifically by the down-regulation of the pregenomic/core promoter, which results in the reduced DNA synthesis of HBV. Currently, the mechanism by which HBV overcomes the observed p53-mediated restriction of replication is tinder investigation.

• 대한임상검사과학회지
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• 제45권3호
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• pp.102-107
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• 2013

Hepatitis A (HA) is an acute infectious disease of the liver caused by the Hepatitis A virus (HAV). In acute HA, the presence of anti-HAV IgM is detectable and about 3 weeks after exposure, its titre increases over 4 to 6 weeks. Anti-HAV IgG is detectable within a few days of the onset of symptoms. IgG antibodies continue to last for years after infection and provide lifelong immunity to the host. This study was performed to investigate the current seroprevalence of anti-HAV antibodies in Jeonbuk province, South Korea. A total of 591 (male 322, female 269) serum samples were collected in July 2011 to June 2012. We tested the antibodies of anti-HAV IgG and IgM using a Modular E170 (Roche Diagnostics, Germany), and analysed the serum alanine aminotransferase (ALT) levels by HITACH 7600-100 (HITACH, Japan). The overall seroprevalence of anti-HAV IgG was 84.6% (500/591), and the rate of females (85.9%) was higher than males (83.5%). According to the decade of age, seroprevalence of anti-HAV IgG were as follows; 68.8% (11/16) in the under 10 years old category, 100% (19/19) in the 10~19 category, 96% (48/50) in the 20~29 category, 83.6% (56/67) in the 30~39 category, 84.3% (123/146) in the 40~49 category, 83.3% (135/162) in the 50~59 category, 83.1% (54/65) in the 60~69 category, 78.1% (32/41) in the 70~79 category, and 88% (22/25) in the over 80 category. Total seroprevalence of anti-HAV IgM was 3.4% (20/591), and according to gender, the seroprevalence of male (3.1%) was very similar to that of female (3.7%). Through this study, we know that the seroprevalence of anti-HAV antibody in north-west Jeonbuk province, South Korea, was high. Only children under the age of 10 remain susceptible to HAV infection. Vaccination against HAV is not needed at the present time for the people of Jeonbuk province, South Korea, but a vaccination should be recommended and the improvement in sanitary conditions and personal hygiene should be highlighted.

• 대한바이러스학회지
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• 제27권2호
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• pp.115-128
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• 1997

Three cDNA fragments located within NS5 region of HCV were synthesized by RT using viral RNA extracted from blood sample of Korean patient as a template. The cDNAs were amplified by PCR, cloned into the T-vector, and the nucleotide sequences were determined. Comparative analysis of the nucleotide and amino acid sequence of NS5 cDNAs showed that it is closely related with HCV type 1b. The cloned NS5 cDNA showed 91-94% homology at the nucleotide sequence level and 96-98% homology at the amino acid sequence level with several strains of the HCV type 1b. The NS5 cDNAs were subcloned into E. coli expression vectors to construct pRSETA5-1, pTHAN5-1, pRSETC5-2, pRSETBB1, pRESTCB1 and pRSETB-H3. Expression of the NS5 proteins was achieved by inducing the promoter with isopropyl-thio-${\beta}$-D-galactoside (IPTG) and confirmed by SDS-polyacrylamide gel electrophoresis. The NS5 proteins were immunoreactive against sera from Korean hepatitis C patients in Western blot analysis. Among the recombinant NS5 proteins, pRSETAS-1 plasmid derived protein, coded from aa2022 to aa2521 of HCV polyprotein, showed the strongest immunoreactivity against sera from Korean hepatitis C patients in immunoblot analysis. These results suggest that NS5 proteins would be useful as an antigen for detection of antibody against HCV in the blood samples.