• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.651-651
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• 2013

Templated strategy is a very powerful tool for creating multi-dimensional self assembly of nanomaterials. Since viral protein cages have a uniform size with a well-defined structure, they can serve as an excellent template for the formation of a three-dimensional self-assembly of synthetic nanoparticles. In this study, we have examined the feasibility of the 3D self-assembly of gold nanoparticles of various sizes using a brome mosaic virus (BMV) capsid with cysteine groups expressed on its surface as a scaffold for the assembly. It was found that the three-dimensional clusters of gold nanoparticles with a designed structure were attainable by this approach, which was verified by transmission electron microscope (TEM) and dynamic light scattering (DLS) analysis.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.36-45
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• 2008

Studies with the transmission electron microscope were used to detect and attempt to identify viruses infecting sweetpotato (Ipomoea batatas) and other Ipomoea species. Flexuous-rods, short curved-rods, and spherical virus-like particles were observed in cells of symptomatic plants. Also, various cytopathic changes such as crystals, vesicles, fibril structures, and cylindrical inclusions were observed. The present study showed that some of these cytopathic changes were associated with some viral groups, which might be helpful in diagnosis.

• IMMUNE NETWORK
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• v.2 no.1
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• pp.1-5
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• 2002

Estimated number of adults and children newly infected with HIV-1 during 2001 alone is 5 million in total. An effective vaccine, in addition to education & public health approaches, has been believed to be the best option to stop the HIV-1 transmission, especially for developing countries. Among AIDS vaccine candidates, DNA vaccine is relatively safe and, in a certain extent, mimics some attributes of live attenuated vaccine, with regard to in vivo gene expression & the type of immunity induced. We recently demonstrated that DNA vaccines expressing SIVmac239 structural and regulatory genes, augmented with coadministration of IL-12 mutant induced the strongest T cell responses, resulting in low to undetectable setpoint viral loads, stable $CD4^+$ T cell counts, and no evidence of clinical diseases or mortality by day 420 after challenge. This finding is the second demonstration, following the protective result of live attenuated SIV vaccine in SIVmac-rhesus monkey model, which was known to have safety problem. So, our DNA vaccines could give a significant impact on HIV-1 epidemic by slowing or stopping the spread of HIV-1, leading to eventual eradication of HIV-1 and AIDS in the population.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.1
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• pp.117-125
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• 2010

The tropical tasar silkworms, Antheraea mylitta (D) produce famous silk 'Kosa' in central part of India. Due to outdoor rearing it became susceptible to viral infection including cytoplasmic polyhedrosis virus (CPV). The common mode of entry of cytoplasmic polyhedrosis virus is per os and cause gresserie disease to the larvae. Histopathological studies elucidated the insect CPV virus produces infective polyhedral inclusion bodies (PIBs) in the midgut cell cytoplasm of virus infected fifth instar larvae. The PIBs multiply enormously in the cytoplasm without invading the nucleus. Ultrastructural studies confirmed the pathological effects of CPV on in midgut cell cytoplasm. The multiplication of polyhedral inclusion bodies took place into the vacuoles and form virogenic stromata in the cytoplasm of cells. However, the encapsulations of polyhedral inclusion bodies into the polyhedrin protein occurred and polyhedra were released into the lumen. At the late stage of infection, cells showed the regressed cytoplasmic organelles with large vacuoles and elongated mitochondria. Hence, the horizontal transmission of CPV causing the midgut cells disintegration in the tasar silkworm, Antheraea mylitta (D) confirmed during infection.

• Clinical and Molecular Hepatology
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• v.24 no.4
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• pp.351-357
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• 2018

The advent of novel, direct-acting antiviral (DAA) regimens for hepatitis C virus (HCV) infection has revolutionized its treatment by producing a sustained virologic response of more than 95% with few side effects and no comorbidities in the general population. Until recently, ideal DAA regimens have not been available to patients with severe renal impairment and end-stage renal disease because there are limited data on the pharmacokinetics, safety, and efficacy of treatment in this unique population. In a hemodialysis context, identifying patients in need of treatment and preventing HCV transmission may also be a matter of concern. Recently published studies suggest that a combination of paritaprevir/ritonavir/ombitasvir and dasabuvir, elbasvir/grazoprevir, or glecaprevir/pibrentasvir successfully treats HCV infection in chronic kidney disease stage 4 or 5 patients with or without hemodialysis.

• Korean Journal of Radiology
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• v.21 no.5
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• pp.537-540
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• 2020

Recently, some global cases of 2019 novel coronavirus (COVID-19) pneumonia have been caused by second- or third-generation transmission of the viral infection, resulting in no traceable epidemiological history. Owing to the complications of COVID-19 pneumonia, the first symptom and imaging features of patients can be very atypical and early diagnosis of COVID-19 infections remains a challenge. It would aid radiologists and clinicians to be aware of the early atypical symptom and imaging features of the disease and contribute to the prevention of infected patients being missed.

• Journal of Preventive Medicine and Public Health
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• v.16 no.1
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• pp.13-18
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• 1983

This study was attempted to define epidemiologically the possibility and the magnitude of sexual transmission of HBV in Korea. Two groups of prostitutes; one group (309) deals with Koreans, the other group (126) deals with American soldiers stationing in Korea, were tested for the presence of HBsAg and anti-HBs. The prevalence rate of HBsAg or anti-HBs was significantly higher in prostitutes who deal with Koreans (41.7%) than in prostitutes who deal with American soldiers (30.2%) (p<0.025). Among the prostitutes who deal with American soldiers, there was no appreciable difference in the prevalence rate of HBsAg or anti-HBs by the duration of prostitution. However, among the prostitutes who deal with Koreans, the prevalence rate was increased with the duration of prostitution, although it did not reach the statistically significant level (p=0.12). There was no remarkable association between the prevalence rate of HBsAg or anti-HBs and educational level, history of operation or history of transfusion. The data support the possibility of sexual transmission of viral hepatitis B but it seems seems sexual transmission does not contribute significantly to the prevalence rate of HBsAg or andi-HBs in Korea.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.186-192
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• 2001

A primary culture of human fetal hepatocytes was obtained through a therapeutic abortion process at 26 weeks of gestation period. More than $10^8$ cells were seeded on a plastic plate. These hepatocytes were infected with hepatitis B virus (HBV). The HBV was purified from serum of one chronic HBV carrier. Transformed hepatocytes were subcultured in a 10% FBS-supplemented medium. The morphology of the transformed cell was epithelial-like. The cells from the first pass showed signs of early proliferation and had a latent period of more than 3 months after 6-7 passages. After the rest period, the transformed cell proliferated actively and they were subcultured every three days. Transformed hepatocytes were characterized by detection of the HBV transcript by RT-PCR. The secretion of virions from transformed cells was investigated by PCR with the cell medium. Two types of virions secreted into the culture medium were examined by using the transmission electron microscope. Another approach to study the secretion of virions in to culture medium was carried out with HBV antibody. HBsAg was detected in the culture medium of transformed cells using ELISA and Western blot analyses. These data suggested that the human fetal hepatocyte cell line has been established by infection of HBV, in which this cell line secreted viral particles into the culture medium.

• The Journal of Korean Society of Virology
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• v.29 no.4
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• pp.201-209
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• 1999

Results of the studies on the morphologic and molecular biologic characteristics of Hantaan virus (HTNV), one of the etiologic agents of Hemorrhagic fever with renal syndrome (HFRS), revealed that HTNV was a member of Family Bunyaviridae and its RNA divided into three segments. And the nucleotide sequences of these segments also were known and the differences in nucleotide sequences of HTNV from other members of genus Hantavirus were clearly evaluated. But the morphorgenesis, pathogenesis of HFRS and the replication time had not been clearly determined. In this study, to estimate the replication time of HTNV in Vero E-6 cells, Vero cells were infected with HTNV 76/118 strain, and cells were harvested from two hours post-infection up to 24 hours at two hours-intervals. Harvested cells were treated with ordinary techniques for electron microscopy and immune-electron microscopy. And then thin sections were observed under transmission electron microscope. HTNV particles were not found in the cytoplasm and in the extracellular space between $2{\sim}8$ hours after inoculation of virus, but virus particles were observed in extracellular space near the cell membrane of Vero-E6 cells 10 hours after infection. In immune electron microscopy, mature HTNV particles in extracellular spaces and immature virus labelled with gold particles in the cytoplasm of Vero E-6 cell 10 hours after infection of HTNV could be seen. This results suggest that the replication time of HTNV might be about 10 hours.

• Korean Journal of Veterinary Research
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• v.57 no.4
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• pp.209-214
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• 2017

Wild raccoon dogs (Nyctereutes procyonoides koreensis) may play a role transmitting several pathogens to humans and pet animals. Information concerning the incidence of rabies, canine distemper virus (CDV), canine parvovirus (CPV), canine adenovirus type 2 (CAdV-2), canine parainfluenza virus type 5 (CPIV-5), and canine herpesvirus (CHV) is needed in wild raccoon dogs. In total, 62 brain samples of raccoon dogs were examined for rabies virus (RABV) and CDV, and 49 lung samples were screened for CDV, CAdV-2, CPIV-5, and CHV. No RABV, CAdV-2, CPIV-5, or CHV was identified, but nine CDV antigens (8.1%, 9/111) were detected. Moreover, 174 serum samples from wild raccoon dogs were screened for antibodies against the five major viral pathogens. The overall sero-surveillance against CDV, CPV, CAdV-2, CPIV-5, and CHV in wild raccoon dogs was 60.3%, 52.9%, 59.8%, 23.6%, and 10.3%, respectively. Comparisons of the sero-surveillance of the five pathogens showed that raccoon dogs of Gyeonggi province have slightly higher sero-positive rates against CDV, CPV, and CHV than those of Gangwon province. These results indicate high incidences of CDV, CPV, and CAdV-2 in wild raccoon dogs of two Korean provinces and a latent risk of pathogen transmission to companion and domestic animals.