Adenoviruses are icosahedral virions containing double-stranded linen DNA. They are 70 nm to 90 nm in diameter and capsid is composed of 252 capsomeres. Several members of this group, including types commonly associated with respiratory disease in man, are capable of producing malignant tumors in young hamsters and a few types have been shown to be oncogenic in young rat. Previous report involving effect of caffein on transformation induced by Adenovirus type 12 [9] has been carried out. The present report represents a continuation of previous study. To obtain evidence concerning the of(tract of MNNG (N-methyl-N'-nitro-N-nitroguanidine) on transformation, investigation of adenovirus type 12 of this group was undertaken. For practical consideration it was desirable to investigate the effect of MNNG on the adenovirus type 12-induced transformation in L cell. Results were as following 1. Adeno virus type 12 induced transformation was enhanced in the presence of MNNG. 2. Yields of adeno type 12 virus in L cell were slightly inhibited by treatment of MNNG.
Adenoviridae* ; Animals ; Bedding and Linens ; Capsid ; Cricetinae ; DNA ; Methylnitronitrosoguanidine ; Rats ; Virion

Expression of the cDNA of the VP1 gene on the genome RNA B segment of infectious pancreatic necrosis virus (IPNV) DRT strain in E. coli and a recombinant baculovirus were carried out. The VP1 gene in the peal-pol clone (Lee et al 1995) was cleaved with XbaI and transferred into baculovirus transfer vector, pBacPAK9 and it was named pBacVP1 clone. The VP1 gene in the pBacVP1 clone was double-digested with SacI and PstI and then inserted just behind 75 phage promoter and the 6x His region of the pQE-30 expression vector, and it was called pQEVP1. Again, the 6xHis-tagged VP1 DNA fragment in the pOEVPl was cleaved with EcoRl and transferred into the VP1 site of the pBacVPl, resulting pBacHis-VPl recombinant. The pBacHis-VP1 DNA was cotransfected with LacZ-Hyphantria cunea nuclear polyhedrosis virus (Lacz-HcNPV) DNA digested with Bsu361 onto S. frugiperda cells to make a recombinant virus. One VP1-gene inserted recombinant virus was selected by plaque assay, The recombinant virus was named VP1-HcNPV-1. The 6xHis-tagged VP1 protein produced by the pQEVPl was purified with Ni-NTA resin chromatography and analyzed by SDS-PAGE and Western blot analysis. The molecular weight of the VP1 protein was 94 kDa. The recombinant virus, VP1-HcNPV-1 did not form polyhedral inclusion bodies and expressed VP1 protein with 95 kDa in the infected S. frugiperda cells, which was detected by Western blot. The titer of the VP1-HcNPV-1 in the first infected cells was 2.0x10(5) pfu/ml at 7 days postinfection.
Bacteriophages ; Baculoviridae ; Blotting, Western ; Chromatography ; Clone Cells ; DNA ; DNA, Complementary ; Electrophoresis, Polyacrylamide Gel ; Genome ; Inclusion Bodies ; Infectious pancreatic necrosis virus* ; Molecular Weight ; Nucleopolyhedrovirus* ; Recombination, Genetic* ; RNA

In order to search for anti-Herpes simplex virus (HSV) type-1 agents from Korean medicinal herbs and Korean traditional prescriptions (herb complexes), we selected 80 medicinal herbs and 45 prescriptions, based on a review of the Korean traditional medicine books. Both methanol extracts and boiling-water extracts were tested by means of the MTT assay (tetrazolium based colorimetric assay). Ten of the 125 methanol extracts: CM-11, CM-18, CM-19, CM-21, CM-22, CM-39, MM-3, MM-18, MM-29, MM-73 (see explanation of nomenclature below), showed efficacy against HSV-1. Twelve of the water extracts: CW-2, CW-3-I, CW-3-II, CW-18, MW-3, MW-5 MW-6, MW-12, MW-47, MW-69, MW-73 and MW-75 were active. #3 (individual herb) and #73 (individual herb) were interesting because both water and methanol extracts were active. Especially, #3 is a part of composition of Hong-il-laksamd ngbang and Hojanghaedokt'ang which have anti-HSV-1 activitives. The SI value of MW-69 and CW-18 was relative high as 10.2+/-0.7 and 11.8+/-2.2. The cytotoxic effect on Vero cells of Panch' n-ch' ngbang, Taraxacum platycarpum H. Dahlst. and acycloguanosine was determined by MTT assay. Water extracts of Panch' ngch' ngbang (prescription) and Taraxacum platycarpum H. Dahlst. showed very weak cytotoxic effects on Vero cells at > 100 mug/ml but acycloguanosine showed strong cytotoxic effects on Vero cells at > 100 mu g/ml. As a result, #3, #73, MW-69 and CW-18 are considered as potentially useful for anti-HSV-1 agent and will be the focus of further research. Abbreviations: CM - methanol extracts of traditional prescriptions; CW - water extracts of traditional prescriptions; MM - methanol extracts of individual herbs; MW - water extracts of individual herbs.
Abbreviations ; Acyclovir ; Herpes Simplex* ; Herpesvirus 1, Human ; Mass Screening* ; Medicine, Korean Traditional ; Methanol ; Plants, Medicinal* ; Prescriptions* ; Simplexvirus* ; Taraxacum ; Vero Cells ; Water

PCR implication using the primers for gag, pol and rev genes in BLV (bovine leukemia virus) proviral DNA and syncytium assay were carried out for the Korean native goats experimentally infected with bovine leukemia virus to investigate pathogenesis of BLV in the goats, and to establish a model animal for BLV infection. The oligonucleotide primers used in PCR revealed very high specificity, The minimal amount of FLK-BLV cellular chromosomal DNA to detect the integrated BLV proviral DNA was 10 ng. The peripheral blood lymphocytes from the goat infected with BLV were examined at regular intervals by PCR amplification and syncytium assay. Pol or gag genes were detected in none of three infected goats at the 1st week post-infection (p.i.). At the 4th week p.i., one of three goats showed the amplified gag gene. Thereafter detection rates for the genes were increased, indicating that the BLV proviral genes were integrated in all of the lymphocytes from three goats, at the 16th weeks p.i., when it was evident in syncytium assay that the lymphocytes from all of three goats were infested with infective BLV. Investigating the tissues from the necropsied goats at the 8th month p.i., the amplified BLV proviral genes and infective BLV were detected in all of the peripheral lymphocytes from three infected-goats. Among various tissues examined, the amplified BLV proviral genes were observed in spleen and superficial cervical, mandibular and retropharyngeal lymph nodes, and the infective BLV, in superficial cervical and mandibular lymph nodes. It was assumed that the Korean native goat was quite susceptible to BLV infection, indicating that the goat could be a good model animal for BLV.
Animals ; Cattle ; Deltaretrovirus Infections ; DNA Primers ; DNA* ; Enzootic Bovine Leukosis* ; Genes, gag ; Genes, rev ; Giant Cells ; Goats* ; Leukemia ; Leukemia Virus, Bovine* ; Lymph Nodes ; Lymphocytes ; Polymerase Chain Reaction* ; Sensitivity and Specificity ; Spleen

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-NIH 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.
Animals ; Encephalitis Virus, Japanese ; Encephalitis Viruses* ; Encephalitis Viruses, Tick-Borne ; Encephalitis* ; Guinea Pigs ; Korea*

To investigate the NS4 region of JEV, NS4 cDNA of K94P05 (JEV strain isolated from Korea in 1994) was amplified by RT-PCR and analyzed by sequencing PCR product. Genomic size of NS4 was 1212bp and nucleotide sequence was compared with that of other JEV strains. Nucleotide homology between JaOAr582 and K94P05 was 91.1% and that between Beijing and K94P05 was 89.8%, respectively. But the nucleotide sequence of I region of JaOAr582 and K94P05 showed 97.0% homology and that of Beijing and K94P05 did 95.8% homology. NS4 protein was expressed as a form of fusion protein by a prokaryotic expression system. The induced fusion product showed a lower molecular weight than predicted size and remained insoluble. The NS4 protein might be cleavages by E. coli protease. Concluding above results, high hydrophobicity of the NS4 protein supported the fact that this protein played a role as a membrane component and the poor nucleotide sequence conservativity among JEV strains suggested that this region might be important to adapt each viral growth environment.
Asian Continental Ancestry Group* ; Base Sequence ; DNA, Complementary ; Encephalitis Virus, Japanese* ; Encephalitis, Japanese* ; Humans ; Hydrophobic and Hydrophilic Interactions ; Korea* ; Membranes ; Molecular Weight ; Polymerase Chain Reaction

Sequence comparison of the RNA-dependent RNA polymerase of human caliciviruses (HuCVs) from Korean children with gastroenteritis revealed significant genetic variation among them. cDNA clones were produced from the HuCVs collected from pediatric population during a period of 1987-1994. The application of reverse transcription-polymerase chain reaction (RT-PCR) using primers directed to the RNA-dependent RNA polymerase region within ORF1 of Norwalk virus (NV) showed that 13.7% of HuCVs yielded PCR products of similar size to the NV prototype, NV8Flla/68/US, with exceptions of HuCV185/87/Korea and HuCV1115/90/Korea. Computer analyses showed that the PCR products had a continuous protein encoding frame on the positive strand, and contained GLPSG and YGDD amino acid motifs at the predicted distance from primers. Alignment of the amino acid sequences of HuCVs with previously published sequences for Snow Mountain agent (SMA), NV, and Sapporo/82/Japan indicated that these strains can be divided into four major genogroups. There were 10 (45%) SMA-like CVs, one (4.5%) NV-like HuCVs, two (9%) Sapporo-like HuCVs, and nine (41%) unidentified HuCVs. This fourth genogroup should be investigated further. HuCV185/87/Korea and HuCV1115/90/Korea, Sapporo-like CVs, were genetically distinct from previously characterized HuCVs and more closely related to known animal CVs. One of the animal CV-like strain, HuCV185/87/Korea, showed nucleotide and amino acid homology of only 67% and 73% with the prototype Sapporo/82/Japan. Further characterization of animal and human CV genomes and studies of possible cross-transmission of CVs from animals to humans are likely to be beneficial in understanding the epidemiology of HuCVs.
Amino Acid Motifs ; Amino Acid Sequence ; Animals ; Child ; Clone Cells ; DNA, Complementary ; Epidemiology ; Gastroenteritis ; Genetic Variation ; Genome ; Genotype ; Humans* ; Korea* ; Norwalk virus ; Polymerase Chain Reaction ; RNA Replicase ; Snow

Multiple species of muridae and arvicolidae rodents serve as the natural reserviors of hantaviruses. Hantaviruses are distributed in rodent populations world-widely even in geographical areas where hemorrhagic fever with renal syndrome (HFRS) has not been reported. Serologic diagnosis of infection, using hantaviral antigen, indicates that hantaviruses are wider distributed in wild rodents. This study was designed to intended the hantavirus infection among wild rodents captured in Kyebang mountain, Kangwon-do in Korea. A total of 216 wild rodents in 3 species were trapped in July and September in 1995. Serological evidence for hantaviruses infection were tested against five hantavirus antigens by indirect immunofluorescent antibody technique (IFA). Among 100 Eothenomys regulus, 78 Apodemus peninsulae and 38 Apodemus agrarius (IFA). Among 100 Eothenomys regulus, 78 Apodemus peninsulae and 38 Apodemus agrarius; 12 C. regulus, 15 A. peninsulae and 6 A. agrarius were IF antibody positive against hantaviruses. This data suggest that Eothnomys regulus and Apodemus peninsulae would be a natural reservoir of hantaviruses.
Animals ; Diagnosis ; Gangwon-do ; Hantavirus Infections* ; Hantavirus* ; Hemorrhagic Fever with Renal Syndrome ; Korea ; Muridae ; Murinae ; Rodentia*

In this study, the feasibility of identification and genotypic differentiation of enteroviruses was investigated by using nested reverse transcription-polymerase chain reaction (nested RT-PCR), single-stranded conformation polymorphism (SSCP), and restriction fragment length polymorphism (RFLP) techniques. Two hundred seventy-four clinical samples were assayed by both nested RT-PCR and tube culture method using MRC-5 and MK cells; 58 (86.6%) out of 67 enterovirus culture-positive samples contained enteroviral RNA. In addition, 114 (55.1%) of 207 samples from patients with suspected enteroviral CNS disease with negative viral cultures were positive by the nested RT-PCR. The nested RT-PCR products were genotyped by the SSCP method and the results were compared with serotypes. We could differentiate 6 subtypes, 3 of which are similar to coxsackievirus B3, B5, echovirus 11, plus 3 other subtypes. RFLP cleaved with Sty I, Bgl I, and Xmn I yielded characteristic patterns for each laboratory strains. This study demonstrates the usefulness of the RT-PCR for the rapid diagnosis of enterovirus infection and the potentials of the SSCP method for differentiation of enterovirus strains.
Central Nervous System Diseases ; Diagnosis ; Enterovirus B, Human ; Enterovirus Infections ; Enterovirus* ; Genotype* ; Humans ; Polymorphism, Restriction Fragment Length ; Polymorphism, Single-Stranded Conformational ; RNA

The present study was designed to estimate the seroprevalence of NLVs among diarrheagenic children and in healthy adults in Seoul and its vicinity with the use of an EIA and an Western blot (WB) based on recombinant Norwalk virus capsid protein (rNV) and crude virus preparations as antigen. Seroconversion was observed in 34 (83%) of 41 tested using the EIA and in 21 (54%) of 39 using the WB, suggesting that the NLVs with epitopes common to rNV are prevalent in Seoul area. Diarrheal children who were known to have been infected with several other strains of the NLVs showed no significant antibody response to the rNV. Infection with rNV occurred earlier in life: primary infections with rNV were common before the age of 6 months and over 91% of children had evidence of infection by that age by the EIA. Since the amount of the NLV antigens available for seroepidemiologic surveys is limited, we tried to detect NLV antibody by using crude virus preparations as antigen. One crude virus preparation of a child whose stool yielded genetically distinct NLV revealed the presence of the plural number of bands upon SDS-PAGE, but precipitated only one band (62 kDa) after the WB with a serum (collected 10 days after the onset of symptoms) of another diarrheal child. The WB assay we present in this report revealed that the NLVs are prevalent among Korean population and that the sera contained antibody to a single major structural protein, with molecular sizes of 58 to 62 kDa, compatible with the sizes reported for the Norwalk virus and Snow Mountain agent proteins, respectively. When the results of the WB were compared with those obtained by the EIA, the EIA antibody assay was sensitive enough to detect an antibody rise of as much as 4096-fold but not as specific as the WB. The WB assay presented in this paper will provide a powerful tool to elucidate not only antigenic structures of the NLVs but also seroepidemiology of the NLV infection. The availability of an unlimited source of antigen will enable a large scale serologic studies that will greatly increase our understanding of the role of NLVs in human enteric illness.
Adult ; Antibody Formation ; Blotting, Western ; Capsid Proteins ; Capsid* ; Child ; Electrophoresis, Polyacrylamide Gel ; Epitopes ; Humans ; Norovirus* ; Norwalk virus* ; Seoul* ; Seroepidemiologic Studies* ; Snow