• Proceedings of the Zoological Society Korea Conference
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• 1996.04a
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• pp.56.1-56
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• 1996

No Abstract, See Full Text

• Journal of Microbiology and Biotechnology
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• v.25 no.6
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• pp.936-940
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• 2015

Human papillomavirus (HPV) type 52 is a high-risk HPV responsible for cervical cancer. HPV type 52 is common around the world and is the most common in some Asian regions. The available prophylactic HPV vaccines protect only from HPV types 16 and 18. Supplementing economical vaccines that target HPV type 52 may satisfactorily complement available prophylactic vaccines. A codon-adapted HPV 52 L1 gene was expressed in the methylotrophic yeast Hansenula polymorpha, which is used as an industrial platform for economical hepatitis B surface antigen particle production in China. We found that the recombinant proteins produced in this expression system could form virus-like particles (VLPs) with diameters of approximately 50 nm. This study suggests that the HPV 52 VLPs produced in this platform may satisfactorily complement available prophylactic vaccines in fighting against HPVs prevalent in Asia.

• ALGAE
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• v.28 no.1
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• pp.83-92
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• 2013

The descriptions of galls, or tumors, in red algae have been sparse. K$\ddot{u}$tzing (1865) observed possible galls of Bostrychia but only presented a drawing. Intensive culture observations of hundreds of specimens of the genus Bostrychia over many years have revealed that galls appeared in only a small subset of our unialgal cultures of B. kelanensis, Bostrychia moritziana/radicans, B. radicosa, B. simpliciuscula, and B. tenella and continued to be produced intermittently or continuously over many years in some cultures but were never seen in field specimens. Galls appeared as unorganized tissue found primarily on males and bisexuals, but occasionally on females and tetrasporophytes. The gall cells usually were less pigmented than neighboring tissue, but contained cells with fluorescent plastids and nuclei. The galls were not transferable to other potential hosts. Galls could be produced from gall-free tissue of cultures that originally had galls even after transfer to new culture dishes. Electon microscopy of galls on one isolate (3895) showed that virus-like particles are observed in some gall cells. It is possible that a virus is the causative agent of these galls.

• Journal of fish pathology
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• v.34 no.2
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• pp.177-184
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• 2021

Vaccines based on single-cycle viruses that are replication-incompetent due to knockout of replication-related structural gene(s) are more immunogenic than inactivated or subunit vaccines and can be used as delivery vehicles for foreign antigens without concerns on the reverting to virulent forms. The aim of this study was to develop a delivery vehicle for nervous necrosis virus (NNV)-like particles (VLPs) using G gene deleted single-cycle VHSV (rVHSV-𝚫G). Recombinant single-cycle VHSVs carrying NNV capsid protein gene between N and P gene of rVHSV-𝚫G genome (rVHSV-𝚫G-NNV_Cap) were rescued by reverse genetic technology. The successful expression of NNV capsid protein in cells infected with rVHSV-𝚫G-NNV_Cap was demonstrated by Western blot analysis, and the production of NNV VLPs in infected cells was confirmed using an electron microscopy. The results suggest that single-cycle VHSVs can be used as a safe delivery vehicle for NNV VLPs, and can be extended to other pathogens for the development of prophylactic vaccines.

• Research in Plant Disease
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• v.19 no.4
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• pp.313-318
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• 2013

In March, 2013, twenty symptomatic freesia plants (10 plants of cultivar Shiny Lemon and 10 plants of cultivar Shiny Gold), with striking virus-like symptoms were collected in Cheongju, Korea. The plants showed chlorotic, coalescing, interveinal, whitish, necrotic, mosaic, mottling or dark brown-to-purple necrotic spots on leaves. Freesia crude sap was directly analyzed by transmission electron microscopy, which potyvirus particles as well as long virus-like particles were detected. Total RNA extracts were analyzed for the infection of Freesia sneak virus (FreSV) by reverse transcription (RT)-PCR with primers specific to FreSV coat protein (CP) gene based on the sequences of FreSV isolates (GenBank No. GU071089, FJ807730 and DQ885455), showing 9 of 20 plants were infected. All 1305bp RT-PCR products were cloned and sequenced. Comparisons of nucleotide and deduced amino acid sequences using BLAST and bioinformatics tools resulted in 99 to 100% sequence identity with FreSV isolates FOV, Virginia, and Italy, confirming FreSV in 9 symptomatic freesia plants. Of 9 determined cDNAs of FreSV isolates, sequences of 5 cDNA clones were identical (GenBank No. AB811437) and sequences of 4 cDNA clones were identical (GenBank No. AB811792). To our knowledge, this is the first report of FreSV from Freesia spp. in Korea.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.6
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• pp.327-336
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• 2016

Cervical cancer is the second most prevalent cancer among women, and it arises from cells that originate in the cervix uteri. Among several causes of cervical malignancies, infection with some types of human papilloma virus (HPV) is well known to be the greatest cervical cancer risk factor. Over 150 subtypes of HPV have been identified; more than 40 types of HPVs are typically transmitted through sexual contact and infect the anogenital region and oral cavity. The recently introduced vaccine for HPV infection is effective against certain subtypes of HPV that are associated with cervical cancer, genital warts, and some less common cancers, including oropharyngeal cancer. Two HPV vaccines, quadrivalent and bivalent types that use virus-like particles (VLPs), are currently used in the medical commercial market. While the value of HPV vaccination for oral cancer prevention is still controversial, some evidence supports the possibility that HPV vaccination may be effective in reducing the incidence of oral cancer. This paper reviews HPV-related pathogenesis in cancer, covering HPV structure and classification, trends in worldwide applications of HPV vaccines, effectiveness and complications of HPV vaccination, and the relationship of HPV with oral cancer prevalence.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.139-144
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• 1999

We have now constructed a novel recombinant baculovirus producing fusion protein with Autogrqha c.uliforrzica nuclear polyhedrosis virus (AcNPV) polyhedrin and green fluorescent protein (GFP). The fusion protein expressed by the recombinant baculovirus in insect cells was characterized. The GFP gene was introduced under the control of polyhedrin gene promoter of AcNPV, by fusion in the front or back of intact polyhedrin gene. The recombinant baculoviruses were named as Ac-GFPPOL or Ac-POLGFP. respectively. As expected, the 56 kDa fusion protein was expressed in the recombinant virus-infected cells. Interestingly. however, the fluorescence of GFP in the cells infected with Ac- POLGFP was only detected within the nuclei. and that was observed as polyhedra-like granular particles. In the microscopy of cells infected with Ac-GFPPOL, furthermore, GFP was detected in both cytoplasm and nuclei although most of GFP were present within the nuclei. However, fusion protein produced by recombinant virus did not form polyhedra although the fusion protein was fused with polyhedrin and GFP. It is suggested that difference of GFP location in the infected cells appear to be involved in the region of polyhedrin in the fusion protein, and the polyhedrin in the fusion protein might be responsible for the polyhedra-like granular particles present within nuclei.

• Parasites, Hosts and Diseases
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• v.55 no.2
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• pp.143-148
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• 2017

Toxoplasma gondii infections occur throughout the world, and efforts are needed to develop various vaccine candidates expressing recombinant protein antigens. In this study, influenza matrix protein (M1) virus-like particles (VLPs) consisting of T. gondii rhoptry antigen 4 (ROP4 protein) were generated using baculovirus (rBV) expression system. Recombinant ROP4 protein with influenza M1 were cloned and expressed in rBV. SF9 insect cells were coinfected with recombinant rBVs expressing T. gondii ROP4 and influenza M1. As the results, influenza M1 VLPs showed spherical shapes, and T. gondii ROP4 protein exhibited as spikes on VLP surface under transmission electron microscopy (TEM). The M1 VLPs resemble virions in morphology and size. We found that M1 VLPs reacted with antibody from T. gondii-infected mice by western blot and ELISA. This study demonstrated that T. gondii ROP4 protein can be expressed on the surface of influenza M1 VLPs and the M1 VLPs containing T. gondii ROP4 reacted with T. gondii-infected sera, indicating the possibility that M1 VLPs could be used as a coating antigen for diagnostic and/or vaccine candidate against T. gondii infection.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.2
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• pp.109-123
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• 2020

Objectives: The aims of this study were to review the standards and key components of the standards for disposable masks in Korea, the US, EU, Japan, and China and to evaluate the appropriateness of disposable masks during a virus pandemic. Methods: We reviewed the standards in the above countries and compared their key elements for each standard. For the second purpose, systemic paper gathering using key words like 'mask', 'respirator' 'virus', and 'coronavirus' in the PubMed search engine was performed. Fifty-three papers were selected and reviewed in regard to the appropriateness of test protocols with sodium chloride(NaCl) particles for virus filtration and the effectiveness against viruses. Results: The standards for masks are largely divided into two categories: US standards and EU standards. In Korea, the Ministry of Employment and Labor adapted the EU standards for workers and the Health Masks adopted the Ministry of Employment and Labor standards by the Ministry of Food and Drug Safety. Regarding airborne viral infections, WHO emphasizes only droplet infection, while many studies have shown that small particles enter the air through coughing or sneezing, which increases the possibility of airborne infection. Compared to other particles, various factors such as airborne viability and the ability to replicate the virus in the body are further involved in the virus's airborne infection rate. Airborne infection is classified into absolute air infection, preferential air infection, and opportunistic air infection. The NaCl-certified N95 mask showed good filtration efficiency against viruses and NaCl particles were proved to be a surrogate material for viruses. From this, KF94 is also expected to be effective in blocking viruses. Conclusion: The N95 test method could be used as a surrogate test method for virus filtration. N95-class masks have been found to effectively block viral infections in the air. However, surgical or medical masks are only partially effective against airborne virus infection though they could effectively block large droplet infection. However, most studies considered in this study targeted N95 in foreign countries and studies on masks actually used in Korea are very limited, so studies on microorganisms and reuse on domestic masks should be conducted in the future.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.192-198
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• 2002

Mixed infections of two economically important viruses, Turnip mosaic virus(TuMV) in the family Potyviridae and Ribgrass mosaic virus(RMV) in the genus Tobamo-virus, were studied ultrastructurally on oriental cabbage. TuMV-ACl8 (alpine isolate in Korea) induced chlorotic spots on inoculated leaves of both ‘SSD63’ inbred line known as susceptible to TuMV, and ‘Tambok’ commercial cultivar, known as resistant to the virus, in the early stages of infection. TuMV-C5 (Taiwan isolate) caused severe mosaic and malformation on the upper leaves of ‘SSD63’, and necrotic spots in both inoculated and upper leaves of ‘Tambok’. RMV-CA1 (oriental cabbage isolate from alpine in Korea) induced vein chlorosis, leaf malformation, and midrib necrotic streak in the upper leaves of both ‘SSD63’ and ‘Tambok’. Both oriental cabbages infected with a combination of TuMV-ACl8 and RMV-CA1 showed synergistic symptoms of severe yellowing, severe mosaic, and necrotic spot or vein necrosis on their leaves. A combination of TuMV-C5 and RMV-CA1 produced synergistic symptoms only in ‘SSD63’. In ‘Tambok’ infected with the combination of TuMV-C5 and RMV-CA1, the number of necrotic spots on the inoculated leaves was one half lesser than that on singly infected with TuMV-C5. A few necrotic spots progressed systemically. In cells infected with a combination of TuMV-ACl8 and RMV-CA1 or TuMV-C5 and RMV-CA1, the particles of the two viruses made nonagon-like rings(NLR); one TuMV particle was surrounded loosely by nine RMV particles. Two unrelated viruses of TuMV and RMV were compacted in the central part of the spiral aggregates(SA) that was induced strikingly in cells by the mixed infections. The SA showed NLR in its center of the cross-sectioned side. Many particles of RMV of Tobamovirus were closely associated with Potyvirus-characteristic cylindrical inclusions. The SAs in the mixed infections were formed easily by the Potyvirus of TuMV-ACl8 or -C5 isolates.