• 한국환경보건학회지
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• 제39권3호
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• pp.230-238
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• 2013

Objectives: For our survey of the incidence of influenza viruses among respiratory viral infections in Seoul, we evaluated their prevalence among infectious acute respiratory viral patients in Seoul from 2010 to 2012 through regular surveillance. Methods: For influenza virus detection, we conducted real-time PCR analyses on 2,544 throat specimens collected from patients with respiratory viral infections in Seoul between 2010 and 2012. They were collected and then tested for the presence of influenza viruses through reverse transcription (RT) - polymerase chain reaction (PCR). Results: 19.1% (486/2,544) of the throat specimens were determined to be positive for influenza viruses. The incidences of influenza viral infection in the case of respiratory viral infections through regular surveillance in Seoul were 23.0% (212/923) in 2010, 6.4% (47/738) in 2011, and 25.7% (227/883) in 2012, and 10.8% (275/2,544) of type A, and 8.3% (211/2,544) type B influenza viruses. In addition, the greatest prevalence was in the 20-49 age group (51.6% ), which shows that influenza viruses constituted a major causative agent of acute respiratory viral infections. Conclusions: The distributions of influenza viruses and the epidemiologic patterns of the viral pathogen in acute respiratory viral infectious patients may provide potentially effective data for epidemiological studies in Seoul, Korea.

• 대한약리학회지
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• 제28권2호
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• pp.213-222
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• 1992

Benzopyrene (BP), 7,12-dimehyl benzanthracene (DMBA), nitrosomethyl urea (NUMU) 및 nicotine과 같은 발암성 화학물질들이 바이러스 감염된 vero 세포의 단층 세포 배양에서 I형 단순성포진 바이러스 (HSV-1)의 복제, 세포융해, DNA합성 및 단백질 합성에 미치는 효과를 관찰하였다. 1. BP와 DMBA는 HSV-1의 복제와 세포융해작용을 유의성있게 억제하였으나 nicotine과 NMU는 별로 억제하지 않았다. 2. 모든 발암성 화학물질은 바이러스의 DNA합성을 억제하지 못하였지만 새로 합성되는 후손바이러스 DNA로 부터 표현되는 gamma 단백질의 표현은 BP와 DMBA에 의해서 현저하게 억제되었다. 그러나 모든 발암성 화학물질은 바이러스의 alpha 및 beta 단백질의 합성은 억제하지 못하였다. 이상의 결과로 보아 발암성화학물질이 존재하고 있는 배지내에서 새로 합성되는 바이러스의 DNA로 부터 표현되는 gamma 단백질의 결함이 있음을 알 수가 있었으며 이같은 개념은 발암화학물질의 존재하에서 바이러스의 DNA와 단백질이 거의 정상적으로 합성됨에도 불구하고 바이러스의 복제가 일어나지 않는다는 사실이 뒷받침해주고 있다.

• IMMUNE NETWORK
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• 제4권2호
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• pp.73-80
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• 2004

Viruses are obligate intracellular parasites which cause infection by invading and replicating within cells. The immune system has mechanisms which can attack the virus in extracellular and intracellular phase of life cycle, and which involve both non-specific and specific effectors. The survival of viruses depends on the survival of their hosts, and therefore the immune system and viruses have evolved together. Immune responses to viral infection may be variable depending on the site of infection, the mechanism of cell-to-cell spread of virus, physiology of the host, host genetic variation, and environmental condition. Viral infection of cells directly stimulates the production of interferons and they induce antiviral state in the surrounding cells. Complement system is also involved in the elimination of viruses and establishes the first line of defence with other non-specific immunity. During the course of viral infection, antibody is most effective at an early stage, especially before the virus enters its target cells. The virus- specific cytotoxic T lymphocytes are the principal effector cells in clearing established viral infections. But many viruses have resistant mechanism to host immune responses in every step of viral infection to cells. Some viruses have immune evasion mechanism and establish latency or persistency indefinitely. Furthermore antibodies to some viruses can enhance the disease by the second infection. Immune responses to viral infection are very different from those to bacterial infection.

• 대한의생명과학회지
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• 제2권2호
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• pp.257-265
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• 1996

토끼 바이러스성 출혈증의 원인체를 실험 토끼에 접종하여 증식을 유도하고 간장에서 hematoxylin & eosin 염 색 에서 조직학적 진단과 세포내 viral RNA의 소재를 결정하기 위해 post-unicryl 포매한 block의 절편을 사용하여 단 염색과 전자현미경적 in situ hybridization을 시도하였다. 토끼 출혈증 viral RNA의 보합 결합에 이용하는 probe는 4717에서 4800(84bases)까지 oligonucleotide를 5'말단에 biotin-CE phosphoramidite로 표지하여 사용하였다. 보합결합물의 증명은 신호 표지로서 antibiotin antibody-l0nm gold를 사용하였으며, hybridization이나 증명은 기존 protocol에서 약간의 변법을 사용하였다. 0.02% glutaraldehyde에서 고정하고 unicryl resin 포매한 표본, biotinylated oligonucleotide probe, antibiotin antibody-l0nm gold로 실험한 결과 증강된 신호를 얻을 수 있었다. 특히 전처리를 생략하므로써 실험 과정을 간단하게 하여 신속한 결과를 얻을 수가 있었다. 전자현미경 in situ hybridization을 통하여 토끼 출혈증 바이러스의 주요 표적은 간세포로 감염 세포의 세포질 내 미토콘드리아와 핵 사이에서 immune gold입자가 뚜렷하게 표지 됨으로서 viral RNA를 증명할 수 있었다.

• Molecules and Cells
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• 제37권2호
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• pp.140-148
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• 2014

We identified four basic amino acid residues as nuclear localization signals (NLS) in the C-terminal domain of the prototype foamy viral (PFV) integrase (IN) protein that were essential for viral replication. We constructed seven point mutants in the C-terminal domain by changing the lysine and arginine at residues 305, 308, 313, 315, 318, 324, and 329 to threonine or proline, respectively, to identify residues conferring NLS activity. Our results showed that mutation of these residues had no effect on expression assembly, release of viral particles, or in vitro recombinant IN enzymatic activity. However, mutations at residues 305 (R ${\rightarrow}$ T), 313(R ${\rightarrow}$ T), 315(R ${\rightarrow}$ P), and 329(R ${\rightarrow}$ T) lead to the production of defective viral particles with loss of infectivity, whereas non-defective mutations at residues 308(R ${\rightarrow}$ T), 318(K ${\rightarrow}$ T), and 324(K ${\rightarrow}$ T) did not show any adverse effects on subsequent production or release of viral particles. Sub-cellular fractionation and immunostaining for viral protein PFV-IN and PFV-Gag localization revealed predominant cytoplasmic localization of PFV-IN in defective mutants, whereas cytoplasmic and nuclear localization of PFV-IN was observed in wild type and non-defective mutants. However sub-cellular localization of PFV-Gag resulted in predominant nuclear localization and less presence in the cytoplasm of the wild type and non-defective mutants. But defective mutants showed only nuclear localization of Gag. Therefore, we postulate that four basic arginine residues at 305, 313, 315 and 329 confer the karyoplilic properties of PFV-IN and are essential for successful viral integration and replication.

• 대한바이러스학회지
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• 제30권1호
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• pp.19-28
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• 2000

Two distinct hantaviruses have been isolated from Apodemus agrarius in 1976 and Rattus norvegicus in 1980 in Korea. Since our serosurveys conducted in 1994, a genetically distinct hantavirus from Apodemus peninsulae has been investigated. To isolate hantavirus from Apen insulae captured in Korea, the lung homogenate of seropositive Apeninsulae inoculated Vero E6 cells. Viral antigen was detected in a progressively higher percentage of cells with subsequent passage after 80 days postinoculation. The new isolate from seropositive Apodemus peninsulae was designated Suchong virus after Suchong valley located in northeastern region of South Korea. Comparing with hantaan virus 76-118 strain, Suchong virus-1, 2, 3 and 4 showed the similarity of $71.0{\sim}91.8%$ at nucleotide and $90.9{\sim}94.8%$ at amino acid sequences in 231 nucleotides region of M segment, and the similarity of $75.1{\sim}81.0%$ at nucleotide and $97.5{\sim}100%$ at amino acid sequences in 237 nucleotides of S segment.

• 정보관리연구
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• 제43권2호
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• pp.151-168
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• 2012

구전홍보는 여러 분야에 있어서 효율적인 마케팅 수단으로 활용되어오고 있다. 본 논문에서는 과학기술자 커뮤니티 사이트(www.kosen21.org)의 운영에 구전홍보 전략을 적용해보았다. 회원들이 손쉽게 홍보메일을 발송하고 홍보 브로셔를 배포할 수 있도록 프로그램을 개발하였으며, 구전홍보에 적극 참여한 회원들에 대한 보상책을 마련하였다. 분석 결과 회원들은 마일리지 적립, 상품권 제공과 같은 보상 전략에 긍정적으로 반응하며, 충성회원이 구전홍보에도 적극적으로 참여한다는 것을 알 수 있었다. 단기적이며 즉각적인 반응을 위해서는 이벤트 실시가 효과적이며, 장기적이며 지속적인 반응을 위해서는 충성회원 관리가 효과적이라는 것도 알 수 있었다. 본 논문의 구전홍보 전략과 분석결과는 인터넷 서비스의 운영과 전략 수립에 활용될 수 있으리라 기대된다.

• Biomolecules & Therapeutics
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• 제29권3호
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• pp.249-262
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• 2021

The most effective way to control newly emerging infectious disease, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, is to strengthen preventative or therapeutic public health strategies before the infection spreads worldwide. However, global health systems remain at the early stages in anticipating effective therapeutics or vaccines to combat the SARS-CoV-2 pandemic. While maintaining social distance is the most crucial metric to avoid spreading the virus, symptomatic therapy given to patients on the clinical manifestations helps save lives. The molecular properties of SARS-CoV-2 infection have been quickly elucidated, paving the way to therapeutics, vaccine development, and other medical interventions. Despite this progress, the detailed biomolecular mechanism of SARS-CoV-2 infection remains elusive. Given virus invasion of cells is a determining factor for virulence, understanding the viral entry process can be a mainstay in controlling newly emerged viruses. Since viral entry is mediated by selective cellular proteases or proteins associated with receptors, identification and functional analysis of these proteins could provide a way to disrupt virus propagation. This review comprehensively discusses cellular machinery necessary for SARS-CoV-2 infection. Understanding multifactorial traits of the virus entry will provide a substantial guide to facilitate antiviral drug development.

• 대한수의학회지
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• 제61권2호
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• pp.13.1-13.8
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• 2021

Mammalian reovirus (MRV) causes respiratory and intestinal disease in mammals. Although MRV isolates have been reported to circulate in several animals, there are no reports on Korean MRV isolates from wildlife. We investigated the biological and molecular characteristics of Korean MRV isolates based on the nucleotide sequence of the segment 1 gene. In total, 144 swabs from wild animals were prepared for virus isolation. Based on virus isolation with specific cytopathic effects, indirect fluorescence assays, electron microscopy, and reverse transcription-polymerase chain reaction, only one isolate was confirmed to be MRV from a Korean roe deer (Capreolus pygargus). The isolate exhibited a hemagglutination activity level of 16 units with pig erythrocytes and had a maximum viral titer of 10^5.7 50% tissue culture infectious dose (TCID₅₀)/mL in Vero cells at 5 days after inoculation. The nucleotide and amino-acid sequences of the partial segment S1 of the MReo2045 isolate were determined and compared with those of other MRV strains. The MReo2045 isolate had nucleotide sequences similar to MRV-3 and was most similar (96.1%) to the T3/Bat/Germany/342/08 strain, which was isolated in Germany in 2008. The MReo2045 isolate will be useful as an antigen for sero-epidemiological studies and developing diagnostic tools.

• 한국어병학회지
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• 제34권1호
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• pp.1-7
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• 2021

Red sea bream iridovirus (RSIV), belonging to the genus Megalocytivirus, is the predominant cause of mortality in marine fishes in Korea, including rock bream (Oplegnathus fasciatus). Rockfish (Sebastes schlegelii) are the host fish for RSIV, exhibiting no clinical signs or mortality. Cohabitation challenges, which mimicked natural transmission conditions, were performed to evaluate viral transmission between rock bream and rockfish, and to determine the pathogenicity and viral loads. In cohabitation challenge, artificially RSIV-infected rock bream were the viral donor, and healthy rockfish were the recipient. The results showed that although the donor rock bream had 95-100 % cumulative mortality (>10⁸ viral genome copies/mg of spleen 7-14 days after viral infection), the recipient rockfish did not die, even when the viral genome copies in the spleen were >10⁵ copies/mg. These results indicated asymptomatic infections. Notably, in a reverse-cohabitation challenge (artificially RSIV-infected rockfish as the viral donor and healthy rock bream as the recipient), RSIV horizontally infected from subclinical rockfish to rock bream (10⁷ viral genome copies/mg of spleen 21 days after cohabitation) with 10-20% cumulative mortality. These results suggest that an asymptomatic, infected rockfish can naturally transmit the RSIV without being sacrificed.