• Korean Journal of Veterinary Research
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• v.31 no.2
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• pp.195-199
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• 1991

Infectious pancreatic necrosis(IPN) virus was known as a causative agent of newly recognized viral disease of young rainbow trout characterized by highly contagious, high mortality and necrosis of pancreas. Several strains of IPN viruses were recovered from young rainbow trout that have been shown a typical cinical sign of infectious pancreatic necrosis disease. The field isolate produced cytopathic effect, and multiplied up to $10^{6.0}$ to $10^{6.5}$ $TCID_{50}/0.1ml$ in BT cell culture. In the indirect immunofluorescent assay with trout anti-IPN virus IgG and goat anti-trout IgG FITC conjugate, these isolates were proved to be a IPN virus that were closely related with VR277 strain of IPN virus antigenically.

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.93-102
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• 2000

In this experiment, we studied the sero-positive rate of akabane virus in cattle from Jeju-do and analyzed the seroepidemiological features. In an analysis of 1,051 samples, the positive rate for neutralizing antibody in sera collected in nine regions on Jeju-do was 56.7%. The rate varied with the region. The positive rate was 69.6% in Aewol, 63.1% in Jeju city, 54.4% in Anduck, 51.0% in Hallim, 69.8% in Jocheun, 47.6% in Pyosun, 40% in Daejeong, 30.0% in Harkyung, 71.6% in Namwon, 24.5% in Sungsan, 133.,3% in Seokypo and 44.5% in Gujwa, respectively The rate also depended on the age of the cattle. The positive rate was 67.2% in calves 0- to 12-month old, 48.3% in cattle 13- to 24-month old, 65.4% in cattle 25- to 36-month old, and 65.4% in cattle more than ,B7 months old. To isolate the virus from calves with malformations including arthrogryposis and hydranencephaly, cerebral homogenates were inoculated into Vero cells, which were determined for cytopathic effect (CPE). Vero cells with CPE were examined for Akabane virus using an electron microscope (EM) and indirect immunofluorescent antibody test (EM). Typical virus particles with a width of 90-130nm and specific immunofluorescence in the cytoplasm of infected cells were sought for identification.

• The Plant Pathology Journal
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• v.28 no.4
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• pp.433-438
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• 2012

Dinoflagellates are considered one of the most abundant and diverse groups of marine microplankton and viruses are recognized as one of the significant factors affecting the plankton dynamics. Here, we report basic characteristics of a new dinoflagellate-infecting virus, Heterocapsa pygmaea DNA virus (HpygDNAV) which infects a toxic dinoflagellate, H. pygmaea. HpygDNAV is a polyhedral large virus (ca. 160-170 nm in diameter) propagating in its host's cytoplasm. Because of the virion size, appearance in thin sections, and propagation characteristics, HpygDNAV is assumed to harbor a large double-stranded DNA genome; i.e., HpygDNAV is most likely a nucleocytoplasmic large DNA virus (NCLDV) belonging to the family Phycodnaviridae. Its infectivity is strain-specific, rather than species-specific, as is the case for other algal viruses. The burst size and latent period are estimated to be roughly 100-250 infectious units $cell^{-1}$ and < 96 h, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.569-573
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• 1995

This experiment was carried out to investigate the effect of Azukibean seeds gained from virus-infected plant on the growth and yield of the next generation. In conventional cultivation, plants showed high infection rate, whereas plants in isolation cultivation showed normal growth without virus-infection. It was considered that virus-infection of Azukibean(variety Chungjupat) occurred not because of seed infection but because of insects-vector in growing period. And thread-shaped virus particles were observed in diseased leaf showing mosaic through electron microscope.

• BMB Reports
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• v.29 no.2
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• pp.180-182
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• 1996

One of the essential functions of virus surface proteins is the recognition of specific receptors on target cell membranes, and cellular receptors play an important role in viral pathogenesis. But the earliest steps of hepatitis B virus (HBV) infection, such as hepatocyte receptor interaction with the virus, are poorly understood. Previous work has suggested an important role of the preS1 region of HBV envelope protein in mediating viral binding to hepatocytes. Although hepatitis B virus (HBV) infection appears to be initiated by specific binding of virions to cell membrane structures via one or potentially several viral surface proteins, data showing the identification or isolation of the HBV receptor (s) are not yet available. The receptor-like proteins on the plasma membrane surface of HepG2 cells that bind to PreS1 were separated and identified using affinity chromatography, and the amino-terminal amino acid sequences of the receptor-like proteins were determined.

• Korean Journal of Veterinary Research
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• v.51 no.3
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• pp.209-216
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• 2011

Four strains of fowl adenovirus (FAdV) were isolated from 4 flocks of broiler or layer chickens affected by hydropericardium syndrome in Korea. These FAdVs were classified as serotype 4 by restriction fragment length polymorphism patterns of hexon genes and whole genomes. The virus exhibited cytopathic effects consisting of rounding, ballooning and clustering in primary chicken embryo liver cell cultures. In transmission electron microscopy, virus particles in hexagonal shape aggregated exclusively in the nuclei of hepatocytes of the chickens as the typical appearances in adenovirus infections. Buoyant density of the virus in cesium chloride (CsCl) was 1.34 g/mL. The virus was stable to chloroform, ether, 50~70% ethanol, acidic condition at pH 3, 0.25% trypsin (1 : 250), heat at $50^{\circ}C$ for 30 min, but labile to 100% ethanol, heat at $52{\sim}60^{\circ}C$ for 30 min, 1 M $MgCl_2$ at $50^{\circ}C$ for 1 h, 1 : 2,000 formalin (37%). All of the physicochemical properties pertained to the characteristics of adenoviruses. Eight viral polypeptides were determined in CsCl-purified virus by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.32-40
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• 2019

Symptoms of fig mosaic disease have been noticed on leaves of fig (Ficus carica) for several decades, in Montenegro. In 2014, leaf samples were collected from trees of six fig cultivars in a plantation located in the main fig-producing area of Montenegro, to study the disease. After RNA isolation, samples were tested by RT-PCR for detection of nine fig viruses and three viroids. Four viruses were detected: fig leaf mottle-associated virus 1 (FLMaV-1), fig mosaic virus (FMV), fig mild mottle-associated-virus (FMMaV) and fig badnavirus 1 (FBV-1). Most of the viruses were present in mixed infections. The amplicons of the viruses were directly sequenced from both directions. A BLAST search of these sequences revealed sequence identities with their closest counterparts at GenBank of 92, 97, 92 and 100%, for FLMaV-1, FMV, FMMaV and FBV-1, respectively. Different responses in symptom expression due to the various virus combinations detected have been demonstrated. Variety $Su{\check{s}}ilica$ had the least symptom expression, with only one virus (FBV-1) found. Considering that the production of figs in Montenegro is increasing and has a substantial relevance in this geographic location, the results indicate that more attention should be given to improving the phytosanitary condition of fig trees in the country.

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.529-536
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• 1994

To establish more specific and simple diagnostic methods for detection of the antibodies and antigens of Aujeszky's disease virus(ADV), we designed indirect dot-immunoassay(IDI) and double sandwich dotimmunoassay(DSDI) using the solid phases of nitrocellolose paper and polystyrene plate. The diagnostic efficacy of these methods was investigated. As the sensitivity of IDI was tested by various virus concentration, the specimens with the virus titer above $10^{4.0}TCID_{50}/0.2ml$ showed positive reaction, but that below $10^{1.0}TCID_{50}/ml$ revealed negative. Tonsil emulsion at the virus titer of $10^{4.5}TCID_{50}/0.2ml$ showed the highest sensitivity as diluted by 1/100. In detection of ADV antigens from the various tissues of the rats and pigs infected with ADV, IDI using monoclonal antibody showed the higher specificity as compared with IDI using polyclonal antibody and virus isolation method. The efficacy of the DSDI for detection of ADV antibody was compared with other tests. The sensitivity of DSDI was higher than virus neutralization(VN) and agar gel immunodiffusion test(AGID). Meanwhile, specificity of DSDI was lower than AGID, but similar to IDEA. In comparison with VN test, DSDI showed 96.9% agreement to VN test that is the highest of three tests. In general, application of polyclonal antibody in both tests caused the higher sensitivity but the lower specificty.

• The Journal of Korean Society of Virology
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• v.28 no.4
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• pp.337-345
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• 1998

Hantaviruses are distributed in rodent population world-widely even in geographical areas where hemorrhagic fever with renal syndrome (HFRS) has not been reported. Various species of Family Muridae and Arvicolidae serve as the natural reservoirs of hantaviruses. Hantaan virus, Seoul virus, Puumala virus, Prospect HII virus, Sin Nombre virus and New York virus are members of genus Hantavirus and isolated from lungs of A. agrarius, R. norvegicus, C. glareolus, M. pennsylvanicus, P. maniculatus and P. leucopus respectively. This experiment was intended to find the distribution of hantavirus infection among wild rodents and isolate the hantavirus from lung tissue of seropositve Apodemus peninsulae, and compared the nucleotide and amino acid sequences with prototype of hantaan virus 76-118 strain. Hantaviral sequences were amplified from lung tissues of A. peninsulae by reverse-transcriptase polymerase chain reaction. Alignment and comparison of the 324 nucleotide of G2 region of M-genomic segment diverged 4.6% and 0% at the nucleotide and amino acid levels, and complete N protein-coding region of S-genomic segment diverged 3.7% and 1.4% nucleotide and amino acid levels, respectively. This is the report to spill-over on the hantaan virus from A. agrarius to A. peninsulae in Korea.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.77-83
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• 1994

Three viral strains, causing CPE in porcine alveolar macrophage cell, were isolated from aborted fetus, serum from young pig showing blue-ear sign and lung of suspected pig, respectively. The differential diagnostic results showed no characteristics of Aujeszky's disease virus(ADV), hog cholera virus (HCV), Japanese encephalitis virus(JEV), porcine parvovirus(PPV) and encephalomyocarditis virus (EMCV). However, positive reactions were demonstrated by IFA using monospecific porcine antibodies against Lelystad virus. When the paired sera of experimentally inoculated swine with one of isolate, KPRRSV-l were tested by IPMA, the result indicated that the isolate was related to United States isolate than European LV.