• Korean Journal of Veterinary Research
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• v.31 no.2
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• pp.189-194
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• 1991

Getah virus is known as a causative agent of recognized febrile illness of horses characterized by fever, rash and edema. A serological survey indicated that hemagglutination inhibition antibody against Getah virus was detected in 34% of 464 racehorses from Korean Horse Affairs Association and 57% of 262 ponies from Cheju island, respectively. Several field strains of Getah virus isolated were from the racehorse that have been shown fever and febrile signs in 1989. The field isolates produced cytopathic effect in Vero, MA-104, BHK-21 cell cultures. Especially, they multiplied to the highest titer($10^6TCID_{50}/0.1ml$) in Vero cell cultures. When day-old mice were inoculated with field isolates by the intracerebral route, they showed a typical paralysis sign and died within seven days after inoculation. The guinea pig exhibited skin rash and edema, and died with neural signs after inoculation with the field isolates. In the cross neutralization test and indirect immunofuorescent assay, the field isolates were proved to be closely related to the Sakai strain of Getah virus antigenically.

• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.209-216
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• 1997

Three dimensional structures of envelope protein from Korean isolates and Nakayama-NIH strain of Japanese encephalitis virus (JEV) were deduced by a computer program (HyperChem 4.0 Chemplus 1.0) based on the data of the three dimentional structure of Tick-borne encephalitis virus. In the three dimensional structure of envelope protein, neutralizing epitope and T-helper cell recognition site of C-terminal region of Korean isolates were structually similar to those of Nakayama-NIH but the N-terminal region was not. Korean JE isolates were compared with Nakayama-NIH strain by using cross-neutralization antibody test. Neutralizing activities of Korean isolates derived from guinea pigs were higher than those of Nakayama-NIH strain against Korean isolates, although the polyclonal antibody titers of Nakayama-NlH showed 1:160 to 1:640 against Korean isolates. According to the results from three dimentional structures and cross-neutralization analyses, the antigenic difference between Korean JE isolates and Nakayama-NIH strain may be dependent on structural difference of envelope protein.

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.31-36
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• 2017

Japanese encephalitis (JE) is an important zoonosis caused by the mosquito-transmitted JE virus (JEV), which is a causative agent of reproductive failure in pregnant sows. Detection of JEV antibodies in swine is performed by hemagglutination inhibition (HI), virus neutralization (VN), and the plaque reduction neutralization test (PRNT). The most stringent PRNT is the 90% endpoint PRNT ($PRNT_{90}$). These conventional assays are difficult to carry out in diagnostic laboratories with insufficient instruments or cell culture systems. An alternative assay that is easily conducted and time efficient is required. In this study, we improved the indirect enzyme-linked immunosorbent assay (I-ELISA) with clarified antigen for the detection of JEV antibodies. The I-ELISA results obtained from 175 swine serum samples were compared with HI, VN, and $PRNT_{90}$ results. The sensitivity of I-ELISA was 91.8%, 95.0%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. The specificity of I-ELISA was 92.2%, 94.7%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. Moreover, the I-ELISA results were significantly correlated with the HI (r = 0.93), VN (r = 0.95), and $PRNT_{90}$ (r = 0.92) results. These results suggest that the improved I-ELISA is useful for serosurveillance of JEV in swine.

• The Plant Pathology Journal
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• v.20 no.2
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• pp.155-157
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• 2004

We isolated Rice dwarf virus (RDV) from infected plants in rice fields (Korea, Japan, China, the Philippines and Nepal) and analyzed their genomic dsRNAs by polyacrylamide gel eletrophoresis. The genomic dsRNAs of the isolates showed distinct electrophoretic mobility profiles. The S12 coding to nonstructural protein of Korean isolate (RDV-Kr) was further analyzed by sequencing. The S12 of RDV-Kr was 1,066bp long and coded for a protein composed of 312 amino acids including three open reading frames of P12, P120Pa and P120Pb. The sequence identities were 96% and 98.6% with Japanese isolates (H, AN), 94.7% with Nepalese isolate (NEL), 94% with Chinese isolate (CK) and the Philippines isolate (P).

• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.955-959
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• 2022

Japanese encephalitis (JE) is a vaccine-preventable mosquito-borne disease caused by infection with the Japanese encephalitis virus (JEV). JEV has five genotypes, including genotype V (GV), which is considered ancestral to the other genotypes. The first GV strain, GV Muar, was isolated from a Malayan patient in 1952 and GV did not reappear for 57 years until GV XZ0934 was isolated from a mosquito sample in China. Since 2010, 21 GV strains have been identified in Republic of Korea (ROK). Both GV Muar and GV XZ0934 are more pathogenic than other GI/GIII strains and are serologically distinct. However, because the ROK's GV strains have not been experimentally tested, their characteristics are not known. Characterization of the ROK's isolates is needed to enable development of effective GV strain-based vaccines to protect against GV infections.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.1
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• pp.43-49
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• 2001

We have cloned and characterized an immediate early-1 gene, iel, which is activated immediately upon entrance of the viral genome into the cell nucleus, from Bombyx mori nuclear polyhedrosis virus (BmNPV) K1 strain. This gene encodes a protein 584 amino acids with a predicted molecular weight of 67 kDa. The promoter and coding regions of BmNPV-K1 ie1 showed high homology with Autographa californica nuclear polyhedrosis virus and BmNPV T3 strain. The BmNPV-K1 ie1 was different from amino acid sequence at 4 positions in BmNPV T3. The location of ie1 gene in the BmNPV-K1 genome was confirmed by Southern blot analysis and its expression patterns at the transcriptional level in the infected cells were confirmed by Nerthern hybridization analysis.

• The Plant Pathology Journal
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• v.29 no.3
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• pp.330-337
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• 2013

Rice stripe virus (RSV), the type member of the genus Tenuivirus, transmits by the feeding behavior of small brown planthopper (SBPH), Laodelphax striatellus. To investigate the interactions between the virus and vector insect, total RNA was extracted from RSV-viruliferous SBPH (RVLS) and non-viruliferous SBPH (NVLS) adults to construct expressed sequence tag databases for comparative transcriptome analysis. Over 30 million bases were sequenced by 454 pyrosequencing to construct 1,538 and 953 of isotigs from the mRNA of RVLS and NVLS, respectively. The gene ontology (GO) analysis demonstrated that both libraries have similar GO structures, however, the gene expression pattern analysis revealed that 17.8% and 16.8% of isotigs were up- and down-regulated significantly in the RVLS, respectively. These RSV-dependently regulated genes possibly have important roles in the physiology of SBPH, transmission of RSV, and RSV and SBPH interaction.

• Pediatric Infection and Vaccine
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• v.25 no.1
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• pp.8-16
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• 2018

Purpose: In this study, the clinical and epidemiological characteristics of patients admitted for viral croup were analyzed to evaluate disease severity based on the organism that caused the infection. Methods: We retrospectively reviewed the medical records of 302 patients who were admitted to the Department of Pediatrics at the Wonju Severance Hospital between May 2013 and December 2016 for viral croup. Patients who showed positive results on multiplex polymerase chain reaction were subsequently diagnosed with respiratory virus infection. The Westley scoring system was used to evaluate the severity of viral croup. Results: Of the 302 patients, 149 were admitted due to severe viral croup, including 88 boys and 61 girls, with a boy-to-girl ratio of 1.44:1. About 110 cases of parainfluenza virus infection have been reported, which accounted for almost half of the total cases. The other identified viruses included influenza virus, human rhinovirus, and respiratory syncytial virus. Analysis of the association between severe viral croup and causative pathogen revealed that only parainfluenza type 2 virus showed a significantly high risk. Parainfluenza type 2 virus did not show an age-based difference in frequency but showed relatively a higher frequency of infections during the summer and fall. Conclusions: In this study, parainfluenza virus type 2 was the only virus associated with severe viral croup. To facilitate proper preventive management, treatment, and prognosis evaluation of viral croup, prospective and multicenter studies should assess the additional variables and the severity of the virus. Additionally, further studies should be conducted to assess age-dependent influences, as well as the regional and seasonal incidence of viral infection.

• The Journal of Korean Society of Virology
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• v.29 no.4
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• pp.221-233
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• 1999

Prospect Hill Virus (PHV) is the well known serotype of hantavirus, a newly established genus in family Bunyaviridae. Extensive studies have upheld the original view of PHV genetics with three genes such as nucleocapsid (N) protein, envelope proteins (G1, G2) and RNA dependent RNA polymerase. In this study, we report the existence of additional gene that is encoded in an overlapping reading frame of the N protein gene within S genome segment of PHV. This gene is expected to encode a nonstructural small (NSs) protein and it seems to be only found in PHV infected cell. The presence and synthesis of NSs protein could be demonstrated in the cell infected with PHV using anti-peptide sera specific to the predicted amino acid sequence deduced from the second open reading frame. Ribosomal synthesis of this protein appears to occur at AUG codon at the 83rd base of S genome segment, downstream of N protein initiation codon. This protein is small in size (10.4 KDa) and highly basic in nature. The expression strategy of NSs protein appears that a signal mRNA is used to translate both N and NSs protein in PHV infected cell. 10 KDa protein in virus infected cell lysates can bind to mimic dsRNA. This fact strongly suggests that NSs protein may be involved in virus replication on late phase of viral life cycle.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.217-223
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• 2004

A cathepsin L-like cysteine protease, v-cath, encoded by the baculovirus has been shown to playa role in host liquefaction. We have identified a v-cath gene in the silkworm virus, Bombyx mori nuclear polyhedrosis virus (BmNPV) K1 strain. The 969 bp v-cath has an open reading frame of 323 amino acids. A putative cleavage site and catalytic sites were conserved in BmNPV-K1 v-cath. The predicted three-dimensional structure of BmNPV-K1 v-cath revealed that the overall fold of BmNPV-K1 v-cath is similar to that of other proteases of the papain family. The deduced amino acid sequence of BmNPV-K1 v-cath showed 98% and 97% protein sequence identity to BmNPV T3 strain and to Autographa californica nuclear polyhedrosis virus, respectively. The BmNPV-K1 v-cath differed at 4 amino acid positions from BmNPV T3. The v-cath gene in BmNPV-K1 genome is located on the EcoRV 6 kb and XhoI 9 kb fragments. Northern hybridization analysis of BmNPV K1 v-cath gene revealed that it is expressed late in infection.