No abstract available.
Korea* ; Rotavirus*

The nonstructural protein NSP4, encoded by gene 10 of rotavirus, has been shown to play a role in viral assembly and known to be an enterotoxin, causing diarrhea in mouse pups. NSP4 gene was cloned from CBNU-2 (virulent bovine rotavirus/diarrheic fecal sample) and CBNU-1 (cell-culture adapted bovine rotavirus/isolated from CBNU-2 and 75 times passaged on MA104 cells), respectively, by reverse transcriptase-polymerase chain reaction (RT-PCR) and sequenced and compared. The sequence data indicated that the NSP4 genes of bovine rotavirus (BRV) were 751 bases in length and encoded one open reading frame of 175 amino acids beginning at base 42 and terminating at base 570. Differences in nucleotide sequence between CBNU-2 and CBNU-1 were observed at 6 positions (base 274, 296, 391, 394, 396 and 579). NSP4 gene of BRV exhibited a high degree of nucleotide (90% and 94%) and amino acid sequence (91% and 94%) and amino acid sequence (91% and 97%) homology with those of SA11 and UK but a low degree of nucleotide (77% and 79%) and amino acids sequence (81% and 85%) homology with those of Wa and OSU.
Amino Acid Sequence ; Amino Acids ; Animals ; Base Sequence ; Clone Cells* ; Cloning, Organism* ; Diarrhea ; Enterotoxins ; Korea* ; Mice ; Open Reading Frames ; Rotavirus* ; Virus Assembly

Characterizations of the VP4 (P type) and VP7 (G type) genes of Korean isolates of bovine rotavirus were performed using RT-PCR/RFLP and nucleotide sequencing analysis. After RT-PCR amplification of partial length (1094bp) of the VP4 and full length (1062bp) of the VP7 genes, amplified PCR products were digested with restriction endonucleases and digestion patterns were compared with those of reference rotaviruses. With the VP4 genes, four RFLP (AD) profiles were observed; three (A, B and C) were the same as those of bovine rotavirus NCDV (P[1]), IND (P[5]) and B223 (P[11]), respectively, Profile D was the same as that of porcine rotavirus OSU (p[7]). With the VP7 genes, five RFLP profiles (I-V) were observed; three of them (1, II and III) were the same as those of bovine rotavirus NCDV (G6), Cody I-801 (G8), and B223 (G10), respectively, Profile IV and V were atypical to those of reference bovine rotaviruses used in this study. These two profiles were identified as G6 and G5, respectively, after analyzing and comparing the nucleotide sequences. The G typing analysis revealed that 61.9% (26/42) were G6, which included G6 subtype; 28.6% (12/42) were G5; 7.1% (3/42) were G10; 2.4% (1/42) were G8. The P typing analysis revealed that 54.8% (23/42) were P(5); 28.6% (12/42) were P(7); 11.8% (5/42) were P(11); 4.8% (2/42) were P(1). Our results showed that G6/P(5) were the most prevalent rotaviruses in diarrheic calves in Korea. Also, this is the first report that G5P(7) rotaviruses were identified from cattle with diarrhea.
Animals ; Base Sequence ; Cattle ; Diarrhea ; Digestion ; DNA Restriction Enzymes ; Korea ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length* ; Rotavirus*

No Abstract Available.
Humans ; Infant* ; Korea* ; Rotavirus* ; Sequence Analysis*

PURPOSE: It is important to have the epidemiologic data of rotavirus serotypes for the application of polyvalent rotavirus vaccines. Epidemiological studies of rotavirus serotypes in Korea have been reported only in limited areas with small number of cases. Authors tried to investigate the distribution of rotavirus G serotypes in ChungJu area with RT-PCR. METHOD: Stool specimens were collected from 202 children with acute diarrheal symptoms, who admitted to or visited Kon-Kuk University Hospital in ChungJu from June 1998 to May 1999. Samples were screened for rotavirus with EIA method (TestPack Rotavirus, Abbott Laboratories) and rotavirus G Serotypes were determined by RT-PCR. RESULTS: Rotavirus was positive in 46.6%. The incidence of G serotypes was as follows; G1 10%, G2 10%, G3 28%, G4 26%, and G9 20%. There were three cases of multiple serotypes; G1 with G9, G2 with G9, and G4 with G9. Serotype of G8 was not found. CONCLUSION: The proportion of G serotypes in ChungJu is much different from previous reports. Serotype of G9 was found which had not been reported in Korean children till now. Long term plans for the investigation of rotavirus serotypes must be needed in wide area.
Child ; Chungcheongbuk-do* ; Humans ; Incidence ; Korea ; Rotavirus Vaccines ; Rotavirus*

No abstract available.
Antibodies* ; Egg Yolk* ; Humans* ; Ovum* ; Rotavirus*

Echovirus 6 (ECV6) is the prevalent serotype detected in aseptic meningitis cases in Korea. To analyze the genetic variation of ECV6 isolates recently circulating in Korea, we determined the partial sequence of the VP1 capsid gene from 22 Korean ECV6 isolates and performed pairwise analysis against 42 reference strains from the GenBank database using MegAlign. The 22 Korean ECV6 isolates formed 3 distinct genetic clusters: Kor-lineage I, II, and III. The Korean ECV6 strains showed significant genetic diversity with 14.8~22.8% nucleotide divergence among the 3 different lineages. These ECV6 Kor-lineages were demonstrated to belong to different genetic clusters using VP1 sequence-based phylogenetic analysis, implying that the recently circulating Korean ECV6 strains have potential antigenic variation.
Antigenic Variation ; Capsid ; Databases, Nucleic Acid ; Echovirus 6, Human ; Enterovirus B, Human ; Genetic Variation ; Korea ; Meningitis, Aseptic

Porcine reproductive and respiratory syndrome virus (PRRSV), a member of the genus Arterivirus in the family Arteriviridae, is the most important viral pathogens in swine industry worldwide. Here, we have investigated 5' and 3' cis-acting RNA elements required for PRRSV genome replication. Using the infectious PRRSV cDNA, we have manipulated the genomic RNA to generate mutant genomic RNAs, transfected these mutants into susceptible MARC-145 cells, and examined the competence of RNA replication. We found three genetic factors that were essential for viral replication. First, the cap structure present at the 5'-end of the genome was absolutely required for RNA replication. Secondly, polyadenylation of the genomic RNA at the 3'-end was also essential for RNA replication. Thirdly, approximately 100-nucleotide region just upstream of the N protein-coding region was crucial for genomic RNA replication. Taken together, our findings indicate that replication of PRRSV genomic RNA requires three important cis-acting RNA elements: 5' cap structure, 3' poly(A) motif, and an internal sequence of about 100 nucleotides. Further investigation is needed to elucidate the molecular mechanism(s) of how these elements act on PRRSV genome replication.
Arteriviridae ; Arterivirus ; DNA, Complementary ; Genome ; Humans ; Mental Competency ; Nucleotides ; Polyadenylation ; Porcine Reproductive and Respiratory Syndrome* ; Porcine respiratory and reproductive syndrome virus* ; RNA* ; Swine

Japanese encephalitis virus (JEV) is one of the most important human pathogens, which causes the permanent neuropsychiatric sequelae and even fatal diseases with high mortality and morbidity, especially among children. In this study, we expressed the structural proteins (C, prM, and E) of JEV using a Sindbis virus-based heterologous gene expression vector, the pSinRep5. We designed two expression vectors (pSinRep5/JEV C-E and pSinRep5/JEV C-NS1), which encode the precise coding sequence of JEV C-E and JEV C-NS1 proteins, respectively. These cloned JEV structural protein genes were designed to express under the Sindbis virus subgenomic promoter. Upon the transfection and expression of the pSinRep5/JEV C-E or pSinRep5/JEV C-NS1 plasmid, the transfected cells expressed approximately 55 kDa JEV E prtiens. As designed, the JEV NS1 proteins were expressed only in the SinRep5/JEV C-NS1 RNAtransfected cells. In addition, we found in the pSinRep5/JEV C-NS1-transfected cells that the viral proteins were predominantly localized around the perinuclear membranes. On the other hand, cytoplasmic staining was mainly observed in the pSinRep5/JEV C-E RNA-transfected cells in the absence of NS1 protein. Thus, our system will provide a useful tool to dissect intracellular membrane localization signals located in the JEV structural proteins without handling the infectious JEV viral particles and to characterize viral morphogenesis of this pathogen.
Asian Continental Ancestry Group* ; Child ; Clinical Coding ; Clone Cells ; Cytoplasm ; Encephalitis Virus, Japanese* ; Encephalitis, Japanese* ; Flavivirus ; Gene Expression ; Hand ; Humans ; Intracellular Membranes ; Membranes ; Morphogenesis ; Mortality ; Plasmids ; Sindbis Virus ; Transfection ; Viral Proteins ; Virion

PURPOSES: Rotaviruses are the main cause of infantile diarrheal diseases worldwide. The purpose of this study is to obtain epidemiologic data of rotavirus infections in Korea. METHODS: Stool specimens were collected from 150 patients with acute diarrheal symptoms, who were admitted to Yonsei Medical Center and Chungbuk National University Hospital. After isolating the virus from the specimens, the viruses were identified as rotaviruses by electron microscope and fluorescent microscope after staining with rotavirus VP6-specific monoclonal antibody. RNA was extracted from the specimens by modified phenol/chloroform method. Electropherotying was done with extracted RNA samples after silver staining of the gels. Rotavirus serotyping was done using commercial serotyping ELISA kit. RESULTS: Rate of infection from rotavirus stool samples was 60%. Isolated rotaviruses were all serogroup A and a majority(46.0%) of these viruses were long type. Serotypes 1 and 2 were identified with serotype 1 being the majority(52.2%). There were no differences in these types between 1991 and 1992, and also between Seoul and Cheongju area. CONCLUSION: Electropherotype of rotavirus epidemic in Korea was serogroup A, and long type in the majority. Serotypes of rotavirus epidemic in Korea were type 1 and type 2. These results show that the rotavirus reassortant vaccine developed in America could also handle the rotaviral disease in Korea.
Americas ; Chungcheongbuk-do ; Diarrhea* ; Enzyme-Linked Immunosorbent Assay ; Gels ; Humans ; Korea* ; Prevalence* ; RNA ; Rotavirus Infections ; Rotavirus* ; Seoul ; Serotyping ; Silver Staining