• 한국어병학회지
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• 제15권1호
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• pp.1-7
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• 2002

On April of 2000 and February of 2001, a disease characterized by darkening, ascites and enlargement of the spleen occurred in flounder, Paralichthys olivaceus, farmed near northern and eastern coasts of Korea. Various degree of necrosis including liquefactive-type was observed mainly in hemopoietic tissue of spleen and kindney. Certain tissue such as branchial soft tissue including epithelium showed a similar necrotic findings. But some tissues such as intentine had several necrotic clusters of wandering cells, being possibly leukocytes. Necrotic evidences of blood cells were evident in various tissues including hemopoietic tissues. Necrobiotic bodies were frequently encountered in blood smear preparations. Bullet type-virious were detected in the spleenic cells. Each virion was about 500 nm in diameter and 170nm in length. From these results, this disease was thought to be a rhabdoviral disease.

• 한국동물위생학회지
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• 제35권2호
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• pp.91-97
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• 2012

The strategy for infectious bursal disease (IBD) control and its success rate under field conditions depends on hygiene management, IBD field pressure, level, and variation in maternally derived IBD antibodies. This study investigated the level of IBD-specific antibody by ELISA and the prevalence of IBD virus by PCR in broilers, white-semi broilers, and Korean native chickens raised in Jeongeup, Jeonbuk. IBD-specific maternally derived antibodies were measured from 698 chickens and the mean titers of maternal antibodies were $3,572{\pm}1,402$ in broilers, $1,262{\pm}762$ in white-semi broilers, and $1,932{\pm}912$ in Korean native chickens. At 2 weeks after vaccination, the geometric mean antibody titers of broiler, white-semi broiler, and Korean native chicken were $582{\pm}427$, $3255{\pm}1,080$, and $1,023{\pm}499$, respectively. According to sequence analysis of the variable virion protein 2 gene, 4 isolates were found to be very virulent IBDV, 9 isolates classical virulent, and 2 isolates intermediate plus vaccine strain.

• 한국응용곤충학회지
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• 제32권4호
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• pp.407-413
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• 1993

숙주범위가 서로 다른 Autographa californica NPV(AcNPV)와 Bombyx mori NPV(BmNPV)를 Spodoptera frugiperda(Sf9) 또는 Bombyx mori(BmN-4)의 세포에 동시감염(coinfection)시킨 후, 숙주범위가 확장된 재조합 바이러스를 Sf9세포에서 10종 BmN-4세포에서 2종씩 플라크 순화하여 선발하였다. 각 재조합 바이러스 DNA의 제한효소 분석결과는 한번 이상의 재조합이 일어났음을 보여주었다. 재조합 바이러스 RecB-8의 전자현미경 관찰결과는 다각체의 모양이 모바이러스인 AcNPV나 BmNPV와는 전혀 다른 정사면체 모양이었으며 또한, 모바이러스와는 달리 virion이 다각체에 거의 매립되어 있지 않은 특징을 보였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권2호
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• pp.139-144
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• 2003

Over 350 million people worldwide are chronic carriers of hepatitis B virus (HBV). Chronic viral infections of the liver can progress to cirrhosis, which may ultimately lead to hepatic failure or the development of hepatocellular carcinoma. There are two antiviral drugs on the market approved for clinical management of chronic HBV infections; interferon-alpha and the nucleoside analog lamivudine. However, they showed adverse side-effects. In the rational drug design for such therapies we would like to utilize antiviral drugs that inhibit the HBV replication in the liver. Investigation of natural extracts of silkworm exhibiting antiviral potential was held in the functional HBV polymerase activity and the release of virion particle in the HepG2.2.15 cell lines. HBV-producing transgenic mouse fed with silkworm DNJ molecule was shown as an inhibitor of serum HBV particles. We could represent this DNJ molecule as an antiviral potential complementing conventional therapies after preclinical tests against WHBV-infected animal model, woodchuck.

• 대한수의학회지
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• 제36권4호
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• pp.1013-1016
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• 1996

Since 1993, sudden and massive death has occurred among penaeid shrimp, Penaeus orientalis cultured in Korea. We investigated the pathological characterizations on the spontaneously and experimentally infected penaeid shrimp. The major gross findings of the spontaneous cases were 2-6mm sized-white spots on the inside of the carapace and reddish discolorization. Histopathologically, massive necrosis of lymphoid organ, degeneration and necrosis of epithelia of epidermis and foregut were observed in both spontaneous and experimental cases. Amphophilic to basophilic intranuclear inclusion bodies were readly observed epithelia of epidermis, foregut and gills. Electron microscopy revealed enveloped, non-occuluded ellipsoid to rod shaped virus particles, within the nucleus, in the lymphoid organs and interstitial cells of hepatopancreas of both spontaneously and experimentally infected shrimps. The size of the virion was $375{\times}167nm$, and the nucleocapsid was $290{\times}75nm$. The causative agent causing massive death in penaeid shrimps in Korea resembles baculovirus associated with white spot syndrome (WSBV) occurred in Taiwan in virus morphology and gross and histological changes of the shrimps.

• Biomolecules & Therapeutics
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• 제6권2호
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• pp.139-144
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• 1998

Abstract -Phyllanthus ussuriensis which belongs to Euphorbiaceae has been used as a component of Korean traditional remedy against hepatitis and jaundice. Aqueous methanolic extract of P. ussuriensis was tested for antiviral activity of hepatitis B virus (HBV) in HepG2 2.2.15 cells which were derived through transfection of cloned HBV DNA into HepG2 human hrpatoblastoma cells. P. ussuriensis extract decreased the levels of extracellular HBV virion DNA and inhibited HBV replication at concentrations ranging from 50 to 500$\mu$g/ml. Partitioning of water suspension of the extract revealed that the activity mainly resides in the EtOAc fraction. Consecutive purification of the EtOAc fraction by silica-gel column chromatography resulted in the two active anti-HBV fractions. Southern blot analysis shows that the action mechanisms or active site of the two fractions seems to be different in terms of their inhibition of HBV replication steps.

• 한국식품과학회지
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• 제44권5호
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• pp.638-642
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• 2012

돼지축사에서 채집해온 6개의 육성돈의 분변에서 식중독 유발 바이러스인 HAV와 HEV를 검출하였으며, HAV는 88.3%의 검출율을 보였으며, HEV는 33.3%의 검출율을 보였다. 결과에는 제시하지 않았으나, 염기서열 분석결과 HEV는 사람에게 전염이 가능한 유전자형인 III형이었으며, 실험적으로 사람의 간세포인 PLC/PRF/5에 접종하였을 때 증식이 됨을 확인하였다. 식중독 유발 바이러스인 HAV와 HEV는 오염된 식품이나 물을 섭취하거나 교차 오염에 의해 전염이 가능하기 때문에 돼지축사에서 위생상태의 개선뿐만 아니라 육류를 섭취하기 전인 운송 및 가공과정까지 식중독 유발 바이러스에 의한 교차오염을 막는 노력이 필요하다. HAV와 HEV 모두 검출된 분변에서 HAV를 순수분리하고 빠르게 검출하기 위해 IMS-RT-PCR을 적용하였으며, 항원-항체 반응에 의해 순수하게 HAV만을 분리할 수 있었다. 또한 HAV만이 순수분리 되었는지 재확인하기위해 세포감염을 통해 증식된 바이러스를 확보한 후 nested RT-PCR을 수행한 결과, HAV만을 순수 분리할 수 있음을 확인하였다. 이는 IMS 활용기술이 단순히 항체를 교체함으로써 다른 특정 식중독 유발 바이러스의 다양한 시료에서 바이러스 순수분리 및 검출에 활용 가능성이 있음을 확인하였다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.125.3-126
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• 2003

A near full-length sequence of a new tobamovirus infecting Hibiscus rosa-sinensis L. was determined. The genome consists of 58 nucleotides (nt) 5' UTR, followed by a 4.9 kb ORF which methyl transferase helicase domain (128 kDa), readthrough protein RNA dependent RNA polymerase (RdRp) 185 kDa and a 52 kDa protein. The 128 kDa protein had a maximum homology of 51.4 ％ to TMGMV and amino acids (an) were 54.3 ％ identical to TMV- vulgare strain. The 185 kDa RdRp had a maximum homology of 53.5％ to TMV-Ob and KGMMV-Y and a 59.6％ homology at the an level to CGMMV-SH. The MP gene encodes 282 aa and its theoretical molecular weight is 30.4 kDa. The nt and an sequence identities of MP ranged from 38.8％ to 43.9％ and 30.9％ to 37.9％, respectively. The CP gene encodes 163 residues and with a theoretical molecular weight of 18.2 kDa The (nt) and aa sequences of the CP were 46.9 ％ to 51.6％ and 45.3％ to 57.1％ identical to other tobamoviruses, respectively. The predicted virion origin of assembly (OAS) was located in the CP gene. Phylogenetic trees generated based on the nt and as sequences of RdRp, MP and CP genes indicated that this new virus clustered with subgroup II tobamoviruses. Although the CP ORF of this virus shared a high nt and aa sequence identity with Sunn-hemp mosaic virus (SHMV), Western analysis showed that it is serologically unrelated to SHMV. We propose the name Hibiscus virus S (HVS) for this Singapore isolate. This is the first report on a near full-length sequence of a Tobamovirus that infects hibiscus.

• 대한미생물학회지
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• 제34권5호
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• pp.423-433
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• 1999

A novel bacteriophage, designated as VPP97, that infects the strains of Vibiro parahaemolyticus (hallophilic, Gram-negative bacterium) isolated most commonly from marine environments, has been discovered, and several of its properties have been determined. The plaques were clear and sized $0.6{\sim}1.0\;mm$ in diameter. The virion forms a single band on 70% sucrose gradient and ${\rho}1.50$ CsCl gradient by sucrose gradient centrifugation and CsCl gradient centrifugation respectively. It has a hexagonal head and a relatively long tail, as shown by electron microscopy. Vibrio alginolyticus, Vibrio fluvialis and Vibrio furnissii were also sensitive to this phage. It was almost totally inactivated at $70^{\circ}C$ and at pH below 5 or over 10. The nucleic acid of VPP97 is composed of DNA. The VPP97 had 9 specific structural proteins sized between 21.5 kDa and 97.4 kDa on SDS-PAGE. When V. parahaemolyticus cultures were treated with either phage VPP97 or one of the several antibiotics for 2 hours, the viable number of V. parahaemolyticus treated with the phage VPP97 is lower than that treated with chloramphenicol, erythromycin or penicillin, but not lower than that treated with tetracycline. Mice that have responded to the phage treatment revealed the lower numbers of V. parahaemolyticus in small intestine and less damage on small intestine compared to the untreated mice. Therefore, we suggest that the phage treatment appears effective to the infection by V. parahaemolyticus.

• International Journal of Industrial Entomology and Biomaterials
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• 제11권2호
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• pp.87-91
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• 2005

We have first isolated and characterized a Plutella xylostella granulovirus ($P_xGV$) from dead larvae of P. xylostella in Korea. The granule of $P_xGV$ was ovoidal shape with an approximate measure of $350-400nm{\times}150-200nm$, and each granule contained one single rod-shape virion with a mean size of $150-180nm{\times}20-30nm$. The major granule protein, granulin, had a molecular weight of approximately 29kDa. Whereas the nucleotide sequence of the granulin gene was identical to that of previously reported $P_xGV$, nucleotide sequences of two of three putative p10 genes were slightly different from those of reported $P_xGV$. These results suggested that the $P_xGV$ isolated in this study was a novel isolate containing different genomic information.