Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| sequence and organization of the left multigene family 110 region of the vero-adapted l60v strain of african swine fever virus. | sequencing of the left variable region of the l60v vero cell-adapted strain of african swine fever virus (asfv) showed the presence of three genes belonging to multigene family 110 (mgf110) and of a fourth unrelated gene. this gene was separated from the mgf110 genes by a region rich in direct repeats. the first mgf110 gene, v1l, with 104 codons, was only moderately related to the other two, w1l and w2l, with 124 and 80 codons, respectively. these two genes were closely related, w2l being a trun ... | 1997 | 9482593 |
| genetic heterogeneity of classical swine fever virus in central europe. | the aim of this work was to genetically characterize central european isolates of classical swine fever virus (csfv) and to evaluate the applicability of molecular analysis in the epizootiology of csfv infections. thirty four viruses, derived from central european pigs or wild boar, were examined. all of these viruses were detected by each of three sets of oligonucleotide primers which had been designed for the specific rt-pcr amplification of different genomic regions. comparative sequence anal ... | 1997 | 9495535 |
| generation of cytopathogenic subgenomic rna of classical swine fever virus in persistently infected porcine cell lines. | two biological clones (a.1 and b.2) of the classical swine fever virus strain alfort/187 and the recombinant virus va187-1, derived from a cdna clone of alfort/187, were used to establish persistently infected cultures of the swine kidney cell lines sk-6 and pk-41. it was found that 100% of the cells in the passaged cultures were positive for viral antigen throughout the course of the experiment. additionally, supernatants collected upon passaging of the cells continuously contained high titers ... | 1997 | 9498611 |
| the public health risks associated with wild and feral swine. | wild swine populations (sus scrofa) are present in many regions of the world. large feral populations in north america and australia are principally derived from introduced domestic pigs. in europe, most wild boar are found in germany and poland. while wild swine are certainly a significant reservoir of infection for domestic swine diseases (for example, african swine fever virus in wild boar in sardinia), these swine generally do not constitute a major public health risk. brucella suis infectio ... | 1997 | 9501373 |
| the presence of rna splicing signals in the cdna construct of the e2 gene of classical swine fever virus affected its expression. | e2 is the major neutralizing antigen for classical swine fever virus (csfv) infection. previously, we have cloned and sequenced the e2 cdna of taiwan strain p97 by the reverse transcription-polymerase chain reaction (rt-pcr) method from csfv-infected tissue. the presence of rna splicing donor and acceptor sites were found in the cdna sequence. in this study, transfection of e2 cdna into mammalian cells resulted in the production of a spliced rna. site-directed mutagenesis of the donor and accept ... | 1997 | 9504767 |
| african swine fever virus infection of bone marrow: lesions and pathogenesis. | the effects of african swine fever (asf) virus infection on bone marrow hematopoiesis and microenvironment were determined by studying the sequential development of ultrastructural lesions of bone marrow and blood cell changes. eight pigs (two pigs/infected group) were inoculated by intramuscular route with 10(5) 50% hemadsorbing doses (had50) of the malawi'83 asf virus isolate. two uninfected pigs were used as controls. ultrastructural changes developed by day 3 postinoculation (pi), persisted ... | 1997 | 9066076 |
| the evolution of virus-induced apoptosis. | viruses from several different families are able to exploit their host's cell death programmes so as to maximize viral fitness. consideration of the evolution of such strategies has lead to the suggestion that the virus should inhibit apoptosis, in order to prolong the life of the cell and thereby maximize the number of progeny virions. the host, on the other hand, should stimulate apoptosis thereby inhibiting viral growth and blocking viral spread. for example, the function of the latent membra ... | 1997 | 9447732 |
| an improved elisa for the detection of serum antibodies directed against classical swine fever virus. | the complex-trapping-blocking (ctb) elisa for detection of antibodies against classical swine fever virus (csfv) using two monoclonal antibodies (mabs) directed against envelope glycoprotein e2, has been improved using recombinant csfv e2-antigen. the newly developed ceditest elisa for csfv-ab is a modification of the ctb-elisa as described by wensvoort et al. (1988) and bloemraad et al. (1993). the old ctb-elisa format comprised of a two-step, single-dilution test which had to be performed by h ... | 1997 | 9460193 |
| [last remedy against hog cholera remains on the shelf]. | 1997 | 9599160 | |
| expression of african swine fever virus envelope protein j13l inhibits vaccinia virus morphogenesis. | the african swine fever virus (asfv) strain malawi lil20/1 open reading frame (orf) j13l was expressed in vaccinia virus (vv) from a strong synthetic late promoter as either a complete orf (vsj1) or lacking codons 1-31 (vsj2). each recombinant vv produced a small plaque which rapidly reverted to a normal size upon passage. the yield of infectious virus from a single cycle infection with vsj1 or vsj2 was reduced 50- to 100-fold compared to wild-type (wt) and a revertant virus (vsj5) in which the ... | 1998 | 9603332 |
| characterization of african swine fever virion proteins j5r and j13l: immuno-localization in virus particles and assembly sites. | the j5r open reading frame (orf) of the malawi lil 20/1 african swine fever virus (asfv) isolate encodes a 111 amino acid protein with a putative transmembrane domain at the n terminus. antisera raised against the predicted c-terminal peptide were used to identify the j5r protein by western blotting in cells infected with asfv or with recombinant vaccinia virus expressing the j5r orf. this showed that the j5r protein migrates with an apparent molecular mass of 23-25 kda, depending on the virus i ... | 1998 | 9603333 |
| a conserved african swine fever virus right variable region gene, l11l, is non-essential for growth in vitro and virulence in domestic swine. | the right variable region of the african swine fever virus (asfv) genome is known to contain genes with functions involving virus virulence and host range in swine. a novel open reading frame, orf l11l, which was absent in the non-pathogenic, cell culture-adapted european isolate ba71v, was identified in the pathogenic african isolate malawi lil-20/1. the location of l11l in the right variable region, together with its absence in ba71v, suggested that l11l may have a function in virus virulence ... | 1998 | 9603334 |
| cloning, expression and sequence analysis of the classical swine fever virus nucleocapsid protein. | the dna complementary to the 5'-terminal 1929 nucleotides of classical swine fever virus (csfv; alias hog cholera virus, hcv) lpc vaccine strain rna was cloned and sequenced. the sequence encompasses a 5'-noncoding region (ncr) of 264 nucleotides and an open reading frame (orf) of 1665 nucleotides. the cloned sequence contains genes of four viral proteins, p23, nucleocapsid (core) protein, e0 and part of e1 proteins. alignment of the 5'-terminal 1929 nucleotides of lpc strain with other strains ... | 1998 | 9608668 |
| the recombinant nucleocapsid protein of classical swine fever virus can act as a transcriptional regulator. | the cdna of the nucleocapsid (core) protein of classical swine fever virus (csfv) was generated by reverse transcription-polymerase chain reaction (rt-pcr) and cloned into a eukaryotic expression vector. the effect of the recombinant core protein on the transcriptional regulation of cellular as well as viral promoters was studied. using transient transfection assay, our results demonstrated that the core protein can activate the promoter of human heat shock protein 70 gene, and suppressed the sv ... | 1998 | 9617770 |
| differentiation of types 1a, 1b and 2 bovine viral diarrhoea virus (bvdv) by pcr. | there are two genotypes among bovine viral diarrhoea viruses (bvdv), bvdv1 and bvdv2. within the bvdv1 genotype there are two distinct subgenotypes, bvd1a and bvd1b. serology and monoclonal antibody binding are used to differentiate bvdv from classical swine fever virus (csfv) and border disease virus (bdv), the other members of the pestivirus genus. these techniques are less useful in the differentiation and segregation of viruses within the bvdv species. in this study, differential polymerase ... | 1998 | 9633045 |
| african swine fever: a disease characterized by apoptosis. | the cell tropism, organ distribution and resultant pathology of african swine fever were compared in domestic pigs infected with lethal (malawi) and sublethal (malta) isolates of african swine fever virus (asfv). after infections with both isolates, asfv was predominantly localized in cells of the mononuclear phagocytic system and was not observed in endothelial cells in lymphoid tissue. more severe tissue destruction and cell depletion, associated with high levels of infected macrophages, were ... | 1998 | 9634085 |
| the pathogenesis of african swine fever in the resistant bushpig. | bushpigs and warthogs are natural reservoir hosts of african swine fever virus (asfv) in the wild, showing no clinical signs of disease when infected with the same highly virulent isolates of asfv that induce rapid, haemorrhagic death in domestic pigs. in contrast to domestic pigs, infection of bushpigs with malawi isolate results in low levels of virus replication and lymphocyte apoptosis within the spleen, and a relatively low spread of virus to other lymphoid tissues. however, at 10 days post ... | 1998 | 9634086 |
| infection with classical swine fever virus: effects on phenotype and immune responsiveness of porcine t lymphocytes. | t lymphocytes obtained from pigs infected with a lethal dose of classical swine fever virus were analysed for phenotypic changes in the composition of t-cell subpopulations and for alterations in their immune responsiveness in vitro during the course of disease. viral antigen detected in all subpopulations and the selective depletion of cd4- cd8- gamma/delta t cells showed that peripheral blood t lymphocytes were affected in the terminal stage (14-19 days post-infection) of classical swine fever ... | 1998 | 9460919 |
| characterization of a bovine viral diarrhea virus isolated from roe deer in germany. | the 5' untranslated region (5' utr) of cytopathogenic pestiviruses isolated from two seronegative roe deer (capreolus capreolus) in northern germany was partially sequenced and compared with those of 28 other pestiviruses. due to the occurrence within a narrow location and the complete identity of the sequenced fragments from both roe deer isolates (sh9 and sh11) they seem to belong to the same bovine virus diarrhea virus (bvdv) strain called sh9/11. this strain is highly homologous (up to 93% i ... | 1998 | 9476225 |
| inhibition of nuclear factor kappab activation by a virus-encoded ikappab-like protein. | certain viruses have evolved mechanisms to counteract innate immunity, a host response in which nuclear factor kappab (nf-kappab) transcription factors play a central role. african swine fever virus encodes a protein of 28.2 kda containing ankyrin repeats similar to those of cellular ikappab proteins, which are inhibitors of nf-kappab. transfection of the african swine fever virus ikappab gene inhibited tumor necrosis factor- or phorbol ester-induced activation of kappab- but not ap-1-driven rep ... | 1998 | 9479002 |
| a new assay for classical swine fever virus based on cytopathogenicity in porcine kidney cell line fs-l3. | a new assay termed the dome disappearance method for classical swine fever virus (csfv) using fs-l3 cells with serum-free culture medium was developed. the csfv live vaccine gpe- strain grows well and shows a slight cytopathic effect (cpe) in fs-l3 cells. this cpe results in the disappearance of the unique fluid-filled multicellular domes on a single monolayer of fs-l3 cells. by using this phenomenon, dome disappearance, as a marker of infection, it was possible to determine the titers of csfv a ... | 1998 | 9506817 |
| deletion of a cd2-like gene, 8-dr, from african swine fever virus affects viral infection in domestic swine. | an african swine fever virus (asfv) gene with similarity to the t-lymphocyte surface antigen cd2 has been found in the pathogenic african isolate malawi lil-20/1 (open reading frame [orf] 8-dr) and a cell culture-adapted european virus, ba71v (orf ep402r) and has been shown to be responsible for the hemadsorption phenomenon observed for asfv-infected cells. the structural and functional similarities of the asfv gene product to cd2, a cellular protein involved in cell-cell adhesion and t-cell-med ... | 1998 | 9525608 |
| a novel method for pestivirus genotyping based on palindromic nucleotide substitutions in the 5'-untranslated region. | a simple and practical method was developed for pestivirus genotyping based on analysis of the secondary structures in the 5'-untranslated region (utr). three stable stem-loop structures, v1, v2 and v3, predicted by computer in the 5'-utr, included strictly conserved consensus base-pairings which are shared by all the genotypes of pestivirus or are characteristic to each genotype of pestivirus. on the basis of the palindromic nucleotide substitution at the secondary structural level, six genotyp ... | 1998 | 9562417 |
| evolution of viral dna-dependent dna polymerases. | dna viruses as their host cells require a dna-dependent dna polymerase (pol) to faithfully replicate their genomic information. large eukaryotic dna viruses as well as bacterial viruses encode a specific pol equipped with a proofreading 3'-5'-exonuclease, and other replication proteins. all known viral pol belong to family a and family b pol. common to all viral pol is the conservation of the 3'-5'-exonuclease domain manifested by the three sequence motifs exo i, exo ii, and exo iii. the polymer ... | 1998 | 9562890 |
| is the major capsid protein of iridoviruses a suitable target for the study of viral evolution? | iridoviruses are large cytoplasmic dna viruses that are specific for different insect or vertebrate hosts. the major structural component of the non-enveloped icosahedral virus particles is the major capsid protein (mcp) which appears to be highly conserved among members of the family iridoviridae, phycodnaviridae, and african swine fever virus. the amino acid sequences of the known mcps were used in comparative analyses to elucidate the phylogenic relationships between different cytoplasmic dna ... | 1998 | 9562891 |
| an experimental infection with classical swine fever virus in weaner pigs. i. transmission of the virus, course of the disease, and antibody response. | the spread of classical swine fever (csf) virus (strain lorraine), originally isolated in the first csf infected herd of the 1993-1994 belgian epizootic, was examined in an isolation unit with three adjacent pens and 15 weaner pigs per pen. virus was introduced through experimental inoculation of one weaner pig in the middle pen (pen 2). the experimentally inoculated pig became viraemic 4 days post-inoculation (dpi) and the pen mates at 12 (n = 9) and 14 dpi (n = 5). the first viraemia in pens 1 ... | 1998 | 9563158 |
| an experimental infection with a classical swine fever virus in weaner pigs. ii. the use of serological data to estimate the day of virus introduction in natural outbreaks. | in a companion paper a logistic regression model of seroprevalence over time was developed on the basis of data obtained during an experimental infection of weaner pigs with classical swine fever (csf) virus. the model was applied to seroprevalence data from three outbreaks of the 1993-1994 epizootic to test whether the model could predict correctly the day of virus introduction into the herd. it was concluded that the logistic regression model has potential as a tool to estimate in retrospect t ... | 1998 | 9563159 |
| the african swine fever virus proteins p54 and p30 are involved in two distinct steps of virus attachment and both contribute to the antibody-mediated protective immune response. | the nature of the initial interactions of african swine fever (asf) virus with target cells is only partially known, and to date only the asf virus protein p12 has been identified as a viral attachment protein. more recently, antibodies to viral proteins p54 and p30 have been shown to neutralize the virus, inhibiting virus binding and internalization, respectively. therefore, we investigated the role of these proteins in the receptor-mediated asf virus endocytosis in swine macrophages, the natur ... | 1998 | 9568043 |
| specific interaction of eukaryotic translation initiation factor 3 with the 5' nontranslated regions of hepatitis c virus and classical swine fever virus rnas. | translation of hepatitis c virus (hcv) and classical swine fever virus (csfv) rnas is initiated by cap-independent attachment (internal entry) of ribosomes to the approximately 350-nucleotide internal ribosomal entry segment (ires) at the 5' end of both rnas. eukaryotic initiation factor 3 (eif3) binds specifically to hcv and csfv iress and plays an essential role in the initiation process on them. here we report the results of chemical and enzymatic footprinting analyses of binary eif3-ires com ... | 1998 | 9573242 |
| complete genomic sequence of border disease virus, a pestivirus from sheep. | the genus pestivirus of the family flaviviridae comprises three established species, namely, bovine viral diarrhea virus (bvdv), classical swine fever virus (csfv), and border disease virus from sheep (bdv). in this study, we report the first complete nucleotide sequence of bdv, that of strain x818. the genome is 12,333 nucleotides long and contains one long open reading frame encoding 3, 895 amino acids. the 5' noncoding region (ncr) of bdv x818 consists of 372 nucleotides and is thus similar i ... | 1998 | 9573288 |
| the major structural protein of african swine fever virus, p73, is packaged into large structures, indicative of viral capsid or matrix precursors, on the endoplasmic reticulum. | african swine fever virus (asfv) is a large enveloped dna virus that shares the striking icosahedral symmetry of iridoviruses. to understand the mechanism of assembly of asfv, we have been studying the biosynthesis and subcellular distribution of p73, the major structural protein of asfv. sucrose density sedimentation of lysates prepared from infected cells showed that newly synthesized p73 was incorporated into a complex with a size of 150 to 250 kda. p73 synthesized by in vitro translation mig ... | 1998 | 9573294 |
| a recombinant classical swine fever virus stably expresses a marker gene. | the gene coding for bacterial chloramphenicol acetyltransferase (cat) was inserted in frame into the viral npro gene of the full-length cdna clone pa187-1 of the classical swine fever virus (csfv) strain alfort/187. rna transcribed in vitro from the resulting plasmid was transfected into sk-6 porcine kidney cells. infectious progeny virus va187-cat recovered from transfected cells had growth characteristics indistinguishable from those of parental virus va187-1. in cells infected with va187-cat ... | 1998 | 9573312 |
| inducible gene expression from african swine fever virus recombinants: analysis of the major capsid protein p72. | a method to study the function of individual african swine fever virus (asfv) gene products utilizing the escherichia coli lac repressor-operator system has been developed. recombinant viruses containing both the laci gene encoding the lac repressor and a strong virus late promoter modified by the insertion of one or two copies of the lac operator sequence at various positions were constructed. the ability of each modified promoter to regulate expression of the firefly luciferase gene was assaye ... | 1998 | 9580160 |
| expression of the glycoprotein e2 of the classical swine fever virus in escherichia coli. | the glycoprotein e2 sequences of classical swine fever virus (strain p97) were cloned, sequenced and expressed in e. coli. result from sds-polyacrylamide gel electrophoresis analysis of expressed proteins revealed the presence of a prominently stained band corresponding to a molecular mass of 61 kda, which is in agreement with the predicted size from the dna sequence. the recombinant e2 protein contained an aminoterminal tag of six histidines that could be used for purification by the nickel che ... | 1998 | 9592734 |
| african swine fever virus infection in the argasid host, ornithodoros porcinus porcinus. | the pathogenesis of african swine fever virus (asfv) infection in ornithodoros porcinus porcinus was examined in nymphal ticks infected with the asfv isolate chiredzi/83/1. at times postinfection (p.i.) ranging from 6 h to 290 days, ticks or dissected tick tissues were titrated for virus and examined ultrastructurally for evidence of virus replication. the asfv infection rate in ticks was 100% in these experiments, and virus infection was not associated with a significant increase in tick mortal ... | 1998 | 9499019 |
| lymphocyte apoptosis during classical swine fever: implication of activation-induced cell death. | infection of pigs with classical swine fever virus (csfv), a member of the flaviviridae family, causes a severe leukopenia, particularly notable with the lymphocytes. the goal of this study was to analyze mechanisms behind this csfv-induced lymphopenia. to this end, the kinetics of leukocyte depletion, the appearance of apoptotic cells, and virus infection of leukocytes after infection of pigs with the virulent csfv strain brescia were analyzed. depletion of b and t lymphocytes was noted as earl ... | 1998 | 9499036 |
| a retention signal necessary and sufficient for endoplasmic reticulum localization maps to the transmembrane domain of hepatitis c virus glycoprotein e2. | the hepatitis c virus (hcv) genome encodes two envelope glycoproteins (e1 and e2). these glycoproteins interact to formin a noncovalent heterodimeric complex which is retained in the endoplasmic reticulum (er). to identify whether e1 and/or e2 contains an er-targeting signal potentially involved in er retention of the e1-e2 complex, these proteins were expressed alone and their intracellular localization was studied. due to misfolding of e1 in the absence of e2, no conclusion on the localization ... | 1998 | 9499075 |
| african swine fever virus is wrapped by the endoplasmic reticulum. | african swine fever (asf) virus is a large dna virus that shares the striking icosahedral symmetry of iridoviruses and the genomic organization of poxviruses. both groups of viruses have a complex envelope structure. in this study, the mechanism of formation of the inner envelope of asf virus was investigated. examination of thin cryosections by electron microscopy showed two internal membranes in mature intracellular virions and all structural intermediates. these membranes were in continuity w ... | 1998 | 9499098 |
| thrombocytopenia associated with apoptotic megakaryocytes in a viral haemorrhagic syndrome induced by a moderately virulent strain of african swine fever virus. | a viral haemorrhagic syndrome was induced in 14 pigs by inoculation with an african swine fever (asf) virus strain of moderate virulence, to determine changes in megakaryocyte (mk) numbers and morphology and thus to assess the role of these cells in the thrombocytopenia characteristic of subacute asf. the strain tested induced changes in the proportion of different types of mk (typical nucleated mks, apoptotic mks and immature mks); it also caused subcellular lesions over the first 7 days post-i ... | 1998 | 9500234 |
| a nonessential african swine fever virus gene uk is a significant virulence determinant in domestic swine. | sequence analysis of the right variable genomic region of the pathogenic african swine fever virus (asfv) isolate e70 revealed a novel gene, uk, that is immediately upstream from the previously described asfv virulence-associated gene nl-s (l. zsak, z. lu, g. f. kutish, j. g. neilan, and d. l. rock, j. virol. 70:8865-8871, 1996). uk, transcriptionally oriented toward the right end of the genome, predicts a protein of 96 amino acids with a molecular mass of 10.7 kda. searches of genetic databases ... | 1998 | 9444996 |
| modulation of t cell and monocyte function in the spleen following infection of pigs with african swine fever virus. | infection of pigs with many strains of african swine fever virus (asfv) has been shown to cause a loss or marked decrease in the ability of splenocytes to respond to mitogens. these observations have been extended by cell fractionation and reconstitution experiments to show that the mitogen stimulated proliferative capacity of both the cd4+ and cd8+ t cells is affected. similarly, monocytes which are directly infectable by virus, are functionally defective as antigen presenting cells when added ... | 1998 | 9646434 |
| entry of african swine fever virus into vero cells and uncoating. | african swine fever virus (asfv) enters vero cells by adsorptive endocytosis [valdeira, m.l., geraldes, a., 1985. morphological study on the entry of african swine fever virus into cells, biol cell. 55, 35-40]. electron microscopy of a lysosomotropic drug-controlled penetration indicated that this step takes place in the endosomes, after fusion between the viral envelope and the limiting membrane of the endosome. inhibition studies with colcemid, cytochalasin b, sodium azide, dinitrophenol, lyso ... | 1998 | 9646445 |
| development and evaluation of a novel antigen capture assay for the detection of classical swine fever virus antigens. | an antigen-capture enzyme immunoassay (eia) was developed to detect classical swine fever virus (csfv) antigen directly from 10% w/v tissue suspension. the assay, based on the sandwich principle, uses a biotinylated monoclonal antibody bound to streptavidin-coated microplates as the capture system and a swine anti-csfv antibody and rabbit anti-swine hrpo-conjugate as the detector system. the antigen-capture eia was compared with conventional virus isolation and polymerase chain reaction (pcr) fo ... | 1998 | 9646447 |
| molecular characterization of the 3' noncoding region of classical swine fever virus vaccine strains. | the genomes of classical swine fever virus (csfv) vaccine strains are poorly characterized, and the mechanisms for their attenuation remain unknown. the aim of the present study was to characterize the 3' noncoding region (3' ncr) of a number of attenuated vaccine strains of csfv in order to examine changes in the viral genome after attenuation. the results showed that the 3' ncr:s of porcivac, rovac, russian lk and original chinese vaccine strain contain insertions very similar to that present ... | 1998 | 9654685 |
| low density blood granulocytic cells induced during classical swine fever are targets for virus infection. | classical swine fever virus infection of pigs causes a severe leukopenia and immunosuppression. in the present study, the kinetics of virus infection, and identification of target cells for the virus in peripheral blood were analysed. virus infection was often not detectable before 5-7 days p.i. a minority of animals yielded detectable infected cells at 3 days p.i., but < 5% pbmc. it was not until 10 days p.i. that this figure increased-to 35-70% pbmc depending on the animal. detailed analysis o ... | 1998 | 9656461 |
| membrane-anchored incorporation of a foreign protein in recombinant influenza virions. | the rna polymerase i system for in vivo synthesis of recombinant influenza vrna molecules was used for the expression of a chimeric protein, consisting of the 341-amino-acid ectodomain of the glycoprotein e2 of classical swine fever virus and the 37-amino-acid c-terminal membrane anchor of the influenza virus hemagglutinin (ha). during infection with an influenza a helper virus the amplified pseudo-viral rna was packaged into progeny virions together with influenza vrna segments. the foreign fus ... | 1998 | 9656996 |
| african swine fever virus infection of the bushpig (potamochoerus porcus) and its significance in the epidemiology of the disease. | warthog (phacochoerus aethiopicus), giant forest hog (hylochoerus meinertzhageni) and bushpig (potamochoerus porcus) are known to be susceptible to infection with african swine fever (asf) virus. little however, is known about the ecology of the disease in the bushpig. this study has shown that the bushpig remains viraemic for between 35 and 91 days following infection during which time it is able to infect the tick vector o. moubata. these ticks were able to transmit the disease to pigs. the vi ... | 1998 | 9659687 |
| [the situation of classical swine fever in wild boars in the european community and selected aspects of disease transmission]. | the situation of classical swine fever (csf) in europe is described on the basis of the literature. in the european community, csf is present among wild boars in germany (federal states mecklenburg-western pomerania, brandenburg and lower saxony), in france (northern vosges) and in italy (regio emìlìa romagna in 1997 and sardinia--enzootically infected). infected wild boars are important as a source of infection for domestic pigs in germany. selected aspects of the transmission of csf virus from ... | 1998 | 9674308 |
| a viral mechanism for inhibition of the cellular phosphatase calcineurin. | the transcription factor nfat (nuclear factor of activated t cells) controls the expression of many immunomodulatory proteins. african swine fever virus inhibits proinflammatory cytokine expression in infected macrophages, and a viral protein a238l was found to display the activity of the immunosuppressive drug cyclosporin a by inhibiting nfat-regulated gene transcription in vivo. this it does by binding the catalytic subunit of calcineurin and inhibiting calcineurin phosphatase activity. | 1998 | 9677199 |
| full-length gbv-c/hgv genomes from nine japanese isolates: characterization by comparative analyses. | the genomes of nine gbv-c/hgv isolates from japanese chronic hepatitis patients were fully sequenced and characterized. they shared 85% nucleotide sequence homology with previously characterized isolates from the us and west africa. homology studies and phylogenetic analyses showed that the japanese isolates formed a third group distinct from the established groups 1 and 2. the genetic distances between the three groups of gbv-c/hgv were very similar to the distances between the two classical sw ... | 1998 | 9687865 |
| border disease of sheep and goats. | border disease (bd) is a congenital virus disease of sheep and goats first reported in 1959 from the border region of england and wales. bd virus (bdv) is a pestivirus in the genus flaviviridae and is closely related to classical swine fever virus and bovine virus diarrhoea virus (bvdv). nearly all isolates of bdv are non-cytopathogenic (ncp) in cell culture. there are no defined serotypes but pestiviruses isolated from sheep exhibit considerable antigenic diversity and three distinct antigenic ... | 1998 | 9689745 |
| ultrastructural pathology of the bone marrow in pigs inoculated with a moderately virulent strain (dr'78) of african swine fever virus. | interpretation of changes in bone marrow during infectious processes is quite complex. this paper reports bone marrow lesions observed in pigs inoculated with a moderately virulent asf virus strain and studies their relationship to the pathogenesis of the disease. in this work, we have carried out the structural and ultrastructural study of the bone marrow of 14 large white x landrace pigs that were inoculated by the intramuscular route with 10(5) 50% hemodsorbing doses (had50) of the dominican ... | 1998 | 9690128 |
| macrophage culture: influence of species-specific incubation temperature. | cultured mammalian cells are traditionally maintained at 37 degrees c, despite the fact that core body temperatures differ considerably among mammals. considering the body temperature of the adult pig, comparison was made of porcine macrophage cultures maintained at 37 degrees c and 39.2 degrees c. examination of the cells showed that granularity was higher in macrophages maintained at 39.2 degrees c, although no differences in cell size were observed. the density of mhc class i and ii expressio ... | 1998 | 9692868 |
| a novel approach to the detection of classical swine fever virus by rt-pcr with a fluorogenic probe (taqman). | detection of classical swine fever virus (csfv) and its discrimination from other pestiviruses can be achieved by virus isolation (vi) in cell cultures, antigen detection, or molecular analysis. to simplify the latter, a 5'-nuclease assay (taqman) was developed for the rapid and specific detection of csfv with the minimum of downstream pcr processing. a pair of 5'-non-coding region, panpestivirus-specific pcr primers were assessed in a one-step reverse transcription-pcr with each of 36 diverse p ... | 1998 | 9694320 |
| detection of african swine fever virus in infected pig tissues by immunocytochemistry and in sity hybridisation. | the techniques for determining cellular sites of establishment and persistence of african swine fever virus (asfv) were established in susceptible domestic pigs and the resistant african reservoir hosts, the warthog and bushpig. detection, both in vitro and in vivo, was achieved by in situ hybridisation and immunocytochemistry, focusing principally on specific probes for vp73, a major capsid protein. hybridisation of radio-labelled probes for dna and rna was relatively insensitive and time consu ... | 1998 | 9694328 |
| migration of mitochondria to viral assembly sites in african swine fever virus-infected cells. | an examination by electron microscopy of the viral assembly sites in vero cells infected with african swine fever virus showed the presence of large clusters of mitochondria located in their proximity. these clusters surround viral factories that contain assembling particles but not factories where only precursor membranes are seen. immunofluorescence microscopy revealed that these accumulations of mitochondria are originated by a massive migration of the organelle to the virus assembly sites. v ... | 1998 | 9696857 |
| classical swine fever virus leader proteinase npro is not required for viral replication in cell culture. | the sequence encoding the viral leader proteinase npro was replaced by the murine ubiquitin gene in a full-length cdna clone of the classical swine fever virus (csfv) strain alfort/187. the recombinant virus va187-ubi showed growth characteristics similar to those of the parent va187-1 virus. at two occasions cells infected with va187-ubi exhibited a cytopathic effect and were found to contain a subgenomic viral rna. this rna lacked the same viral genes as the subgenomic rna which has been found ... | 1998 | 9696875 |
| [procoagulant activity in swine leukocytes, infected with the swine classical plague virus]. | an increased level of the procoagulant activity (pca) has been observed in porcine leukocytes in vitro infected with virulent or vaccine strains of hog cholera virus in comparison with intact cells. pca was similarly induced in infected leukocytes from swine immune to hog cholera virus. increased pca levels were detected in culture medium with leukocytes from intact and immune animals infected in vitro with both virulent and vaccine strains of hog cholera virus in comparison with the pca levels ... | 1998 | 9702815 |
| critical factors affecting the diagnostic reliability of enzyme-linked immunosorbent assay formats. | this paper aims to evaluate different formats of the enzyme-linked immunosorbent assays (elisas) for detection of virus-specific antibodies and focuses on factors that may influence the diagnostic reliability of such tests. newly developed and well-established elisas for detection of infections of bovine herpesvirus 1 (bhv1), bovine respiratory syncytial virus (brsv), classical swine fever virus (csfv), pseudorabies virus (prv) and bovine viral diarrhoea virus (bvdv) are used as examples. differ ... | 1998 | 9713894 |
| cholesterol affects african swine fever virus infection. | african swine fever virus (asfv) enters cells by receptor mediated endocytosis and requires a fusion event between the viral envelope and the limiting membrane of the endosome at low ph. in order to investigate the role of cholesterol in the early stages of asfv infection, we have studied the effect of the removal of cell and viral membrane cholesterol by cholesterol oxidase treatment of cells and virions, as well as the effect of some inhibitors of cholesterol synthesis on the infectious pathwa ... | 1998 | 9714715 |
| isolation and characterization of cytopathogenic classical swine fever virus (csfv). | two new classical swine fever virus (csfv) isolates obtained from naturally infected swine were found to exhibit a cytopathogenic (cp) phenotype. according to their reactivity with monoclonal antibodies (mabs) the isolates cpbw1 and cpmvp1 were classified as antigenic types "lothringen'92" and "flandern'90", respectively. in northern blot analyses and pcr assays csfv rna of subgenomic length was detected in infected cells indicating the presence of defective interfering particles. nucleotide seq ... | 1998 | 9722875 |
| serological and immunohistochemical study of african swine fever in wild boar in spain. | a serological and immunohistochemical study of african swine fever was carried out in wild boar killed in seven municipalities in the north of the province of córdoba during two hunting seasons (1991-92 and 1992-93), when the area was affected by the disease. fourteen of 147 wild boar analysed by elisa and immunoblotting had antibodies to african swine fever virus. the immunohistochemical study revealed that four cases (two seropositive and two seronegative) showed immunoreactivity to the anti-v ... | 1998 | 9725185 |
| intracellular virus dna distribution and the acquisition of the nucleoprotein core during african swine fever virus particle assembly: ultrastructural in situ hybridisation and dnase-gold labelling. | african swine fever virus (asfv) is a large complex icosahedral double-stranded dna virus that replicates in the cytoplasm of susceptible cells. assembly of new virus particles occurs within the perinuclear viroplasm bodies known as virus factories. two types of virus particle are routinely observed: "fulls," which are particles with an electron-dense dna-containing nucleoid, and "empties," which consist of the virus protein and membrane icosahedral shell but are without the incorporation of the ... | 1998 | 9740789 |
| pathogenesis of mucosal disease, a deadly disease of cattle caused by a pestivirus. | two biotypes of pestiviruses, cytopathogenic (cp) and non-cytopathogenic (noncp) viruses, are distinguished by their effects on tissue culture cells. in contrast to the bovine viral diarrhoea virus (bvdv) system, only a few cp border disease virus (bdv) and cp classical swine fever virus (csfv) strains have been described. antigenically closely related noncp and cp bvdv can be isolated from cattle with fatal mucosal disease (md) and are called a virus pair. the generation of cp bvdv in an animal ... | 1998 | 9741637 |
| maternal recognition of foetal infection with bovine virus diarrhoea virus (bvdv)--the bovine pestivirus. | pestiviruses are the veterinary viruses with genome homology to human hepatitis c virus (hcv). this group includes classical swine fever virus (csfv), border disease virus of sheep (bdv) and bovine virus diarrhoea virus (bvdv). there are some similarities in the pathology of all three virus infections; in utero transmission to the foetus can cause early embryonic losses, severe congenital abnormalities and, particularly with bvdv, lifelong persistent infections. in situ hybridisation studies hav ... | 1998 | 9741639 |
| immunohistochemical and ultrastructural evidence of hog cholera virus infection of megakaryocytes in bone marrow and spleen. | twelve pigs were inoculated with a highly virulent strain of hog cholera virus (hcv) to study viral infection of megakaryocytes in the bone marrow and spleen. immunohistochemical and ultrastructural examination revealed hcv infection in a small proportion (2.5-9.0%) of these cells from the 2nd to the 9th day after inoculation, at which time the experiment was terminated. megakaryocyte infection accounts for the presence of viral antigens in platelets. the latter may represent a passive vehicle f ... | 1998 | 9749356 |
| [classical swine fever in 1993 in switzerland: molecular-epidemiologic characterization of the virus isolate]. | rt-pcr followed by direct nucleotide sequencing of the amplified cdna was carried out to analyse most of the 5' nontranslated region (5'ntr) of classical swine fever virus (csfv) isolates from the five 1993 disease outbreaks in switzerland. sequence data were compared to other csfv strains, and dendrograms were constructed in order to determine the phylogenetic relationship of the swiss virus strains. dendrograms formed by the analysis of different parts of the 5'ntr were compared. it was shown ... | 1998 | 9757784 |
| comparative detection of classical swine fever virus in striated muscle from experimentally infected pigs by reverse transcription polymerase chain reaction, cell culture isolation and immunohistochemistry. | classical swine fever (csf) is a highly contagious viral disease, which can be transmitted by csfv-contaminated swill. in 1993, four csf outbreaks in switzerland were caused presumably by feeding pigs with improperly heated swill. the aim of the investigations was to find a suitable method for csfv detection in striated muscle samples of infected pigs in order to allow routine testing of meat for virus contamination. the sensitivity of virus detection in striated muscle was compared with the det ... | 1998 | 9763128 |
| african swine fever virus is enveloped by a two-membraned collapsed cisterna derived from the endoplasmic reticulum. | during the cytoplasmic maturation of african swine fever virus (asfv) within the viral factories, the dna-containing core becomes wrapped by two shells, an inner lipid envelope and an outer icosahedral capsid. we have previously shown that the inner envelope is derived from precursor membrane-like structures on which the capsid layer is progressively assembled. in the present work, we analyzed the origin of these viral membranes and the mechanism of envelopment of asfv. electron microscopy studi ... | 1998 | 9765444 |
| application of genetic methods to study the relationship between classical swine fever outbreaks. | eleven viruses isolated between 1993 and 1997 from outbreaks of classical swine fever in the neighbouring countries of slovakia, the czech republic and austria were compared after partial sequencing of the ns5b and e2 genes. viruses collected from south-central and west slovakia were indistinguishable during a period of four years, even when associated with outbreaks of variable severity. outbreaks that occurred in the czech republic in 1996 involved two types of virus, one of which was related ... | 1998 | 9769081 |
| an rt-pcr assay for the specific detection of classical swine fever virus in clinical samples. | a simple reverse transcriptase-polymerase chain reaction (rt-pcr) assay has been developed for the specific amplification of dna after reverse transcription of rna from the classical swine fever virus (csfv). a pair of oligonucleotides was selected from an area of high homology in the genome of csfv strains, but which differed from the corresponding sequences in the genome of bovine viral diarrhea virus (bvdv) strains. using these primers (csfv1-csfv2), a csfv specific dna band of 174 bp was amp ... | 1998 | 9779556 |
| african swine fever virus nl gene is not required for virus virulence. | previously, we described a highly conserved nonessential african swine fever virus (asfv) right variable region gene, nl. deletion of nl from the european pathogenic isolate e70 resulted in almost complete attenuation of the virus in domestic swine. to study gene function further, nl gene deletion mutants were constructed from two pathogenic african asfv isolates, malawi lil-20/1 (mal) and pretoriuskop/96/4 (pr4). unexpectedly, both mal (mal-deltanl) and pr4 (pr4deltanl) null mutants remained hi ... | 1998 | 9780062 |
| classical swine fever virus: discrimination between vaccine strains and european field viruses by restriction endonuclease cleavage of pcr amplicons. | 1998 | 9787502 | |
| [methods of laboratory diagnosis of hog cholera]. | the review emphasizes the significance of laboratory methods for the diagnosis of hog cholera virus. in addition to virus isolation and immunofluorescent method, enzyme immunoassay (eia) of virus-specific antigen and antibodies are recommended. commercial eia kits for laboratory diagnosis of hog cholera virus and test-systems whose development is in progress now are characterized. | 1998 | 9791879 |
| functionality and cell anchorage dependence of the african swine fever virus gene a179l, a viral bcl-2 homolog, in insect cells. | the african swine fever virus gene a179l has been shown to be a functional member of the ced9/bcl-2 family of apoptosis inhibitors in mammalian cell lines. in this work we have expressed the a179l gene product (p21) under the control of the baculovirus polyhedrin promoter using a baculovirus system. expression of the a179l gene neither altered the baculovirus replication phenotype nor delayed the shutoff of cellular protein synthesis, but it extended the survival of the infected insect cells to ... | 1998 | 9811766 |
| the african swine fever virus thymidine kinase gene is required for efficient replication in swine macrophages and for virulence in swine. | african swine fever virus (asfv) replicates in the cytoplasm of infected cells and contains genes encoding a number of enzymes needed for dna synthesis, including a thymidine kinase (tk) gene. recombinant tk gene deletion viruses were produced by using two highly pathogenic isolates of asfv through homologous recombination with an asfv p72 promoter-beta-glucuronidase indicator cassette (p72gus) flanked by asfv sequences targeting the tk region. attempts to isolate double-crossover tk gene deleti ... | 1998 | 9811782 |
| establishment of a serum-free culture cell line, cpk-ns, which is useful for assays of classical swine fever virus. | a stable porcine kidney cell line, cpk-ns, was established and maintained in serum-free culture. a cytopathic effect (cpe) was observed clearly in cpk-ns cells infected with some classical swine fever virus (csfv) strains which did not show the exaltation of newcastle disease virus (end) phenomenon. chromosome condensation and dna fragmentation, a marker for apoptosis, were detected in cells infected with end phenomenon-negative csfv strains. by using the cpe induced by infection with an end phe ... | 1998 | 9820575 |
| identification of a 25-aminoacid sequence from the major african swine fever virus structural protein vp72 recognised by porcine cytotoxic t lymphocytes using a lipoprotein based expression system. | identification of african swine fever virus (asfv) proteins recognised by cytotoxic t lymphocytes (ctl) from swine surviving asfv/nh/p68 infection was assessed using expression vectors based on the pseudomonas aeruginosa outer membrane lipoprotein i gene (opri). viral antigens expressed as fusion lipoproteins were shown to be taken efficiently by porcine blood-derived macrophages incubated with outer membrane protein preparations from transformed e. coli. to assess recognition by ctl the fusion ... | 1998 | 9820580 |
| in vivo effect on pig chromosomes of high dosage vaccine against classic swine fever. | hog cholera virus (hcv) can induce chromosome abnormalities in diseased pigs as well as in those vaccinated with attenuated virus vaccine against classic swine fever. an experiment was made using animals from potency and safety control tests of commercial vaccines in argentina. the different types of chromosomal alterations observed were chromatid and chromosome breaks, chromatid exchanges, polyploid, multiple aberrations cells, and chromosome pulverization. in this study the occurrence of chrom ... | 1998 | 9838191 |
| comparison of a reverse transcription-polymerase chain reaction assay and virus isolation for the detection of classical swine fever virus. | the authors evaluated the ability of a reverse transcription-polymerase chain reaction (rt-pcr) assay to detect classical swine fever virus (csfv) in comparison with virus isolation and detection by an indirect immunoperoxidase assay (vi-ipa). to determine the specificity of the assay, samples from 60 spleens, 45 tonsils, ten submandibular lymph nodes, eight mesenteric lymph nodes and four kidneys, collected from pigs of various ages which had been slaughtered in abattoirs in canada (a populatio ... | 1998 | 9850538 |
| application of a computer program for genetic typing of classical swine fever virus isolates from germany. | the commercial software program hla sequityper (amersham pharmacia biotech), designed originally for human leukocyte antigen typing, was adapted for rapid typing of classical swine fever (csf) virus isolates. the program compares new sequence data with those stored in a database file and calculates the most probable assignment. for generating the csf virus sequence database, 150 bp of the 5' nontranslated genomic region (5'-ntr) from 88 german classical swine fever virus isolates from outbreaks ... | 1998 | 9870589 |
| porcine cells persistently infected with classical swine fever virus protected from pestivirus-induced cytopathic effect. | cytopathogenicity of classical swine fever virus (csfv) depends on the presence of defective particles containing a subgenomic (sg) rna with a defined deletion. in a previous report we described the spontaneous generation of this sg rna and therefore of cytopathogenic (cp) csfv in porcine kidney cell cultures persistently infected with csfv. frequently, some cells survived the cpe and could be further propagated. they remained positive for viral antigen and continued to shed complete virus and i ... | 1998 | 9880012 |
| characterization of immobilization methods for african swine fever virus protein and antibodies with a piezoelectric immunosensor. | a direct piezoelectric flow injection analysis immunoassay for the detection of african swine fever virus and antibodies is presented. the peptide-specific monoclonal antibody 18bg3 and the virus protein 73 were used for detection with a quartz crystal microbalance. accumulation of the analyte on the surface of this mass-sensitive biosensor resulted in a shift of the resonant frequency. highly selective receptor layers were applied on the sensing electrode of the quartz crystal for detection of ... | 1998 | 9883562 |
| prostaglandin a1 inhibits replication of classical swine fever virus. | prostaglandins (pgs) have been shown to inhibit the replication of several dna and rna viruses. here we report the effect of prostaglandin (pga1) on the multiplication of a positive strand rna virus, classical swine fever virus (csfv) in pk15 cells. pga1 was found to inhibit the multiplication of csfv. at a concentration of 5 micrograms/ml, which was nontoxic to the cells, pga1 inhibitis virus production in 99%. in pga1 treated cells the size and number of characteristic classical swine fever fo ... | 1998 | 9921308 |
| molecular cloning and nucleotide sequence of 3'-terminal region of classical swine fever virus lpc vaccine strain. | a cdna of the 3'-terminus of classical swine fever virus (lpc vaccine strain) was cloned and sequenced. the 3431 nucleotides and deduced amino acid sequences were compared with those of other pestiviruses, and the similarity of nucleotide sequences and deduced amino acid sequences were found to be 84-95% and 95-98%, respectively. similar to other isolates of classical swine fever virus, the sequenced region included the non-structural gene p58 (ns5a) and part of p76 (ns5b) gene. the p76 gene of ... | 1998 | 9926397 |
| inactivation of the rnase activity of glycoprotein e(rns) of classical swine fever virus results in a cytopathogenic virus. | envelope glycoprotein e(rns) of classical swine fever virus (csfv) has been shown to contain rnase activity and is involved in virus infection. two short regions of amino acids in the sequence of e(rns) are responsible for rnase activity. in both regions, histidine residues appear to be essential for catalysis. they were replaced by lysine residues to inactivate the rnase activity. the mutated sequence of e(rns) was inserted into the p10 locus of a baculovirus vector and expressed in insect cell ... | 1998 | 9420210 |
| a prokaryotic-like mode of cytoplasmic eukaryotic ribosome binding to the initiation codon during internal translation initiation of hepatitis c and classical swine fever virus rnas. | initiation of translation of hepatitis c virus and classical swine fever virus mrnas results from internal ribosomal entry. we reconstituted internal ribosomal entry in vitro from purified translation components and monitored assembly of 48s ribosomal preinitiation complexes by toe-printing. ribosomal subunits (40s) formed stable binary complexes on both mrnas. the complex structure of these rnas determined the correct positioning of the initiation codon in the ribosomal "p" site in binary compl ... | 1998 | 9420332 |
| african swine fever virus infection induces tumor necrosis factor alpha production: implications in pathogenesis. | we have analyzed the production of tumor necrosis factor alpha (tnf-alpha) induced by in vitro infection with african swine fever (asf) virus (asfv) and the systemic and local release of this inflammatory cytokine upon in vivo infection. an early increase in tnf-alpha mrna expression was detected in asfv-infected alveolar macrophages, and high levels of tnf-alpha protein were detected by elisa in culture supernatants from these cells. when animals were experimentally infected with a virulent iso ... | 1999 | 9971800 |
| a lipid modified ubiquitin is packaged into particles of several enveloped viruses. | an anti-ubiquitin cross-reactive protein which migrates more slowly (6.5 kda) by sds-page than ubiquitin was identified in african swine fever virus particles. this protein was extracted into the detergent phase in triton x-114 phase separations, showing that it is hydrophobic, and was radiolabelled with both [3h]palmitic acid and [32p]orthophosphate. this indicates that the protein has a similar structure to the membrane associated phosphatidyl ubiquitin described in baculovirus particles. a si ... | 1999 | 10037162 |
| oral immunisation of swine with a classical swine fever vaccine (chinese strain) and transmission studies in rabbits and sheep. | seven experiments including a total of 47 pigs, 11 wild boars, 26 rabbits, 10 hares and 16 sheep were carried out to assess the efficacy, safety and transmission of the chinese vaccine strain of the classical swine fever virus (csfv) administrated by the oral route. within 3 weeks after oral vaccination, a clear seroconversion occurred in the pigs. six weeks after vaccination, vaccinated pigs were fully protected against a virulent challenge. the c-strain was not isolated from tonsils, spleen, l ... | 1999 | 10063532 |
| genetic heterogeneity of porcine and ruminant pestiviruses mainly isolated in japan. | the genetic variability of porcine and ruminant pestiviruses was studied by comparative nucleotide sequence analysis of 73 isolates (42 porcine and 31 ruminant), including 65 japanese isolates (35 porcine and 30 ruminant). the 5'-untranslated region (utr) amplified by reverse transcriptase-polymerase chain reaction (rt-pcr) was determined by direct sequencing and phylogenetic analysis was performed from the nucleotide sequence data. most porcine isolates were divided into two major subgroups, cl ... | 1999 | 10068129 |
| an experimental marker vaccine and accompanying serological diagnostic test both based on envelope glycoprotein e2 of classical swine fever virus (csfv). | envelope glycoprotein e2 is the most immunogenic protein of classical swine fever virus (csfv). in a proposed model of the antigenic structure of e2, the n-terminal half of e2 forms two independent structural antigenic units, a and bc. e2 without transmembrane region (e2-tmr) is expressed and secreted into the medium of insect cells by use of the baculovirus expression system. the immune response induced by e2 protects pigs against csfv. recently, we showed that the protective immune response to ... | 1999 | 10073720 |
| incidence of classical swine fever (csf) in wild boar in a densely populated area indicating csf virus persistence as a mechanism for virus perpetuation. | a virological survey was carried out to establish the distribution of classical swine fever (csf) virus among wild boar in the federal state of brandenburg, germany. organ materials and blood samples were collected from 11,670 wild boar shot or found dead during the period march 1995 to december 1997. in total 211 (1.8%) wild boar were positive for csf virus or antigen. the incidence of csf-positive animals decreased continuously from 4.6% at the beginning of the epidemic in 1995 to 0.7% in 1997 ... | 1999 | 10085775 |
| nuclear and nucleolar localization of an african swine fever virus protein, i14l, that is similar to the herpes simplex virus-encoded virulence factor icp34.5. | pcr analysis of the genomes of 18 different african swine fever virus (asfv) isolates showed that the i14l open reading frame (orf) was present as either a long form or short form in all of the isolates. sequencing of the orf from eight isolates confirmed that both forms of the orf were well conserved. antisera raised against the i14l protein identified the long form of the protein as a 21 kda protein expressed late during asfv infection. immunofluorescent analysis of transiently expressed haema ... | 1999 | 10091989 |
| [comparison of laboratory diagnostic methods for the detection of infection with the virus of classical swine fever in the early inspection phase: an experimental study]. | virus isolation in the pk-15 cell culture, two commercial antigen elisas, reverse transcriptional-polymerase chain reaction (rt-pcr), and flow cytometry have been evaluated to detect viremic pigs in the early period of classical swine fever virus (csfv) infection. domestic pigs were experimentally inoculated with the virulent csfv strain 'alfort 187' and two field isolates. csfv isolation and rt-pcr were found to be the most sensitive methods for the detection of highly virulent csfv in the earl ... | 1999 | 10189722 |
| [detection of the hog cholera virus using the polymerase chain reaction]. | a rapid and highly sensitive method for detecting hog cholera virus (hcv) based on a reverse transcription of the polymerase chain reaction (rt-pcr) is developed. primers complementary to the most homologous sites of virus genome in an area coding the precursor for glycoproteins gp44/gp48 are selected. detection of the virus in pathological material by the rt-pcr showed that use of these primers in amplification allows detection of different hcv strains. | 1999 | 10190108 |
| selective stimulation of hepatitis c virus and pestivirus ns5b rna polymerase activity by gtp. | ns5b of the hepatitis c virus is an rna template-dependent rna polymerase and therefore the key player of the viral replicase complex. using a highly purified enzyme expressed with recombinant baculoviruses in insect cells, we demonstrate a stimulation of rna synthesis up to 2 orders of magnitude by high concentrations of gtp but not with atp, ctp, utp, gdp, or gmp. enhancement of rna synthesis was found with various heteropolymeric rna templates, with poly(c)-oligo(g)12 but not with poly(a)-oli ... | 1999 | 10196156 |
| recovery of infectious classical swine fever virus (csfv) from full-length genomic cdna clones by a swine kidney cell line expressing bacteriophage t7 rna polymerase. | a new method for the recovery of infectious classical swine fever virus (csfv) from full-length genomic cdna clones of the c-strain was developed. classical reverse genetics is based on transfection of in vitro transcribed rna to target cells to recover rna viruses. however, the specific infectivity of such in vitro transcribed rna in swine kidney cells is usually low. to improve reverse genetics for csfv, a stable swine kidney cell line was established that expresses cytoplasmic bacteriophage t ... | 1999 | 10204702 |
| efficacy and stability of a subunit vaccine based on glycoprotein e2 of classical swine fever virus. | the purpose of this study was to determine the efficacy and stability of an e2 subunit vaccine against classical swine fever virus (csfv). the vaccine, which contains e2 produced in insect cells by a baculovirus expression vector is a potential marker vaccine, as it allows discrimination between infected and vaccinated pigs. several vaccination-challenge experiments were performed to determine the dose that protects 95% of the vaccinated pigs (pd95), and to determine the stability and efficacy o ... | 1999 | 10227472 |
| [classical swine fever in wild boars in switzerland]. | in may 1998, wild boars with classical swine fever (csf) symptoms were detected in the southern part (canton ticino) of switzerland. csf virus was isolated from the submitted samples and rt-pcr followed by direct nucleotide sequencing of the 5' non-translated region showed that this virus was identical to the isolate previously recognized in wild boars from the area of varese (italy). in most animals, antibodies to csf virus were detected as well. an immediate measurement was taken by limiting t ... | 1999 | 10228397 |