ABSTRACT
We have determined and analyzed the full-length cDNA sequence of a coxsackievirus B3 (CVB3) Korean isolate (CVB3-Korea/97) which has been known as a general human pathogen. The whole genome contains 7,400 nucleotides and has a single large open reading frame with 6,555 nucleotides that encodes a potential polyprotein precursor of 2,185 amino acids. The genome also contains a 5' non-coding region (NCR) of 741 bases and a 3' NCR of 104 bases followed by poly(A) tail. Sequence homologies of nucleotides and deduced amino acids between the CVB3-Korea/97 strain and the prototype (Nancy strain) were 81.7% and 91.5%, respectively. The genes encoding the functional proteins including viral protease and RNA dependent RNA polymerase showed higher homology than those encoding the structural proteins. We have further analyzed the sequences of 5' NCR, VP1 and VP2 of CVB3-Korea/97, which are known as cardiovirulent determining factors at the nucleotide and amino acid levels. Although the CVB 3-Korea/97 strain was isolated from an aseptic meningitis patient without cardiomyopathy, its 234th nucleotide and 165th amino acid were uracil and Asn as same as those of other cardiovirulent strains one. However, the 155th amino acid of VR1, which closely associated with cardiovirulence, was replaced with Arg155 by single nucleoptide substitution from A2916 to T2916. Moreover, additional amino acid substitutions were observed in the flanking region of Asp155. Taken together, aminoacid(s) substitution in VP1 may play a critical role in determining cardiovirulence of the CVB3-Korea/97 strain rather than individual nucleotide replacements in the 5' NCR and/or an amino acid substitution in VP2.
Subject(s)
Humans , Amino Acid Substitution , Amino Acids , Cardiomyopathies , Clone Cells , Cloning, Organism , DNA, Complementary , Genome , Korea , Meningitis, Aseptic , Nucleotides , Open Reading Frames , RNA-Dependent RNA Polymerase , RNA, Messenger , Sequence Analysis , Sequence Homology , UracilABSTRACT
We examined the hepatitis G virus infections among 227 Koreans who were healthy or were suspected of hepatitis and determined the phylogenetic relationship based on a part of the NS-5 region of 5 positive samples. Viral RNA was extracted from sera and cDNA was synthesized and subsequently amplified by RT-PCR (reverse transcription-polymerase chain reaction) or RT-nested PCR using random hexamer and NS-5 specific primers (470-20-1-77F, 470-20-1-211R, HGVNESTFO, HGVNESTRE). Five positives were found to belong to samples of patients showing symptoms of viral hepatitis. Primers used for PCR or nested PCR were derived from the NS-5 region. On the other hand, no amplification was detected using primers derived from the 5'-NCR (G-146F, G-401R). We performed TA cloning and sequencing of 5 amplified fragments, and their sequences were compared with those of foreign isolates of HGV. The phylogenetic analysis using MegAlign programme of DNAstar has shown that the Korean isolates are clustered on the phylogenetic tree. In summary, we confirmed the hepatitis G virus infection in 5 cases out of 12 patients showing the symptoms of viral hepatitis. The phylogenetic analysis of sequences of 5 amplified fragments showed that their relations to each other were closer than those to the foreign HGV isolates reported.
Subject(s)
Humans , Clone Cells , Cloning, Organism , DNA, Complementary , GB virus C , Hand , Hepatitis , Korea , Polymerase Chain Reaction , RNA, ViralABSTRACT
BACKGROUND: To investigate the epidemiology of aseptic meningitis in Korea, we have isolated and characterized enteroviruses isolated from patients with acute meningitis from 1993 to 1998. METHODS: Stool and/or cerebrospinal fluid (CSF) samples from patients with aseptic meningitis were inoculated onto enterovirus-susceptible cell lines. The virus propagation was examined by the presence of cytopathic effects and each viral isolate was further characterized using a neutralization test. RESULTS: Out of 1,127 specimens, 197 enteroviral isolates were obtained mostly from stool samples (82.8 %) of children aged zero to ten years. At least 15 serotypes of enteroviruses, including echoviruses (EV) 3, 6, 7, 9, 25 and 30, coxsackieviruses (CV) B1~B6, and vaccine-derived polioviruses (PV) had circulated during the previous 6 years. The major serotypes that caused outbreaks of aseptic meningitis, were EV30 in 1997 and EV6 in 1998. Although the incidence of virus isolation peaked during summer, we had isolated enteroviruses all the year round in 1998. CONCLUSION: Since 1993, we had confirmed 197 cases of enteroviral meningitis. Outbreaks of aseptic meningitis were mainly caused by EVs, with peaks during the summer months. Our data emphasize that the nationwide surveillance of aseptic meningitis should be expanded and maintained throughout the year.
Subject(s)
Child , Humans , Cell Line , Cerebrospinal Fluid , Disease Outbreaks , Enterovirus B, Human , Enterovirus , Epidemiologic Studies , Epidemiology , Incidence , Korea , Meningitis , Meningitis, Aseptic , Neutralization Tests , PoliovirusABSTRACT
BACKGROUND: To investigate the epidemiology of aseptic meningitis in Korea, we have isolated and characterized enteroviruses isolated from patients with acute meningitis from 1993 to 1998. METHODS: Stool and/or cerebrospinal fluid (CSF) samples from patients with aseptic meningitis were inoculated onto enterovirus-susceptible cell lines. The virus propagation was examined by the presence of cytopathic effects and each viral isolate was further characterized using a neutralization test. RESULTS: Out of 1,127 specimens, 197 enteroviral isolates were obtained mostly from stool samples (82.8 %) of children aged zero to ten years. At least 15 serotypes of enteroviruses, including echoviruses (EV) 3, 6, 7, 9, 25 and 30, coxsackieviruses (CV) B1~B6, and vaccine-derived polioviruses (PV) had circulated during the previous 6 years. The major serotypes that caused outbreaks of aseptic meningitis, were EV30 in 1997 and EV6 in 1998. Although the incidence of virus isolation peaked during summer, we had isolated enteroviruses all the year round in 1998. CONCLUSION: Since 1993, we had confirmed 197 cases of enteroviral meningitis. Outbreaks of aseptic meningitis were mainly caused by EVs, with peaks during the summer months. Our data emphasize that the nationwide surveillance of aseptic meningitis should be expanded and maintained throughout the year.