| secretory pathway limits the enhanced expression of classical swine fever virus e2 glycoprotein in insect cells. | the 3' untranslated region (utr) is an important element that determines the level of recombinant protein expression via baculovirus vectors. previous work using chloramphenicol acetyl transferase as reporter has shown that p10-promoter based baculovirus vectors with the authentic p10 3' utr resulted in higher expression levels than vectors carrying an sv40 early terminator, as part of a lacz selection cassette. to examine whether a similar increase in expression levels could be obtained for bac ... | 2001 | 11223142 |
| enzyme-linked immunosorbent assay using a virus type-specific peptide based on a subdomain of envelope protein e(rns) for serologic diagnosis of pestivirus infections in swine. | peptides deduced from the c-terminal end (residues 191 to 227) of pestivirus envelope protein e(rns) were used to develop enzyme-linked immunosorbent assays (elisas) to measure specifically antibodies against different types of pestiviruses. the choice of the peptide was based on the modular structure of the e(rns) protein, and the peptide was selected for its probable independent folding and good exposure, which would make it a good candidate for an antigenic peptide to be used in a diagnostic ... | 2001 | 11230402 |
| african swine fever virus multigene family 360 and 530 genes are novel macrophage host range determinants. | pathogenic african swine fever virus (asfv) isolates primarily target cells of the mononuclear-phagocytic system in infected swine and replicate efficiently in primary macrophage cell cultures in vitro. asfvs can, however, be adapted to grow in monkey cell lines. characterization of two cell culture-adapted viruses, ms16 and ba71v, revealed that neither virus replicated in macrophage cell cultures. cell viability experiments and ultrastructural analysis showed that infection with these viruses r ... | 2001 | 11238833 |
| evaluation of genetic vaccine against classical swine fever. | classical swine fever is important diseases affecting pigs. it results in great losses in their population and in limitations in the commercial international trade of pigs. the aim of the study was the preparation of the genetic vaccine against csf and the estimation of its safety, protection value and immunogenicity. clinical observations, body temperature and the immune response (haematological and facs analyses) were monitored. pigs vaccinated with the dna vaccine were protected from the chal ... | 2001 | 11257381 |
| evolution of hepatitis c virus genome in chronically infected patients receiving ribavirin monotherapy. | recent results of clinical trials suggest that combination of interferon and ribavirin exhibits an enhanced antiviral effect in the treatment of chronic hepatitis c. to investigate the effect of ribavirin on hepatitis c virus (hcv) infection, we analysed the evolution of the genetic heterogeneity of hcv in relation to the anti-hcv humoral response in patients treated by ribavirin alone. the study population included 35 patients with liver biopsy proven chronic hepatitis c infected with hcv genot ... | 2001 | 11264732 |
| immunogenicity of the e1e2 proteins of hepatitis c virus expressed by recombinant adenoviruses. | the e1 and e2 proteins of hepatitis c virus (hcv) are believed to be the viral envelope glycoproteins that are major candidate antigens for hcv vaccine development. we reported previously that the replication-competent recombinant adenovirus encoding core-e1-e2 genes of hcv (ad/hcv) produces serologically reactive e1 and e2 proteins forming a heterodimer in substantial amounts. here, we examined immunogenicity of the e1e2 proteins copurified from hela cells infected with ad/hcv virus in mice. fu ... | 2001 | 11282207 |
| a prime-boost vaccination strategy using naked dna followed by recombinant porcine adenovirus protects pigs from classical swine fever. | weaned pigs (6-week-old) and 7-day-old pre-weaned piglets were vaccinated with naked plasmid dna expressing the gp55/e2 gene from classical swine fever virus (csfv). both groups of pigs were then given a booster dose of recombinant porcine adenovirus expressing the gp55 gene (rpav-gp55). following challenge with csfv, 100% of weaned pigs and 75% pre-weaned piglets were protected from disease. weaned pigs given a single dose of rpav-gp55 were also protected, but showed a slight increase in temper ... | 2001 | 11295331 |
| vitamin b12 and hepatitis c: molecular biology and human pathology. | cobalamins are stored in high concentrations in the human liver and thus are available to participate in the regulation of hepatotropic virus functions. we show that cyanocobalamin (vitamin b12) inhibited the hcv internal ribosome entry site (ires)-dependent translation of a reporter gene in vitro in a dose-dependent manner without significantly affecting the cap-dependent mechanism. vitamin b12 failed to inhibit translation by ires elements from encephalomyocarditis virus (emcv) or classical sw ... | 2001 | 11296247 |
| construction of recombinant swinepox viruses and expression of the classical swine fever virus e2 protein. | to explore the swinepox virus (spv) as a potential live vector for immunization, a vector was developed for the construction of a recombinant spv carrying foreign genes. in this system, a foreign gene placed under the strong vaccinia virus promoter p(11) can be inserted into the viral thymidine kinase (tk) gene, and the recombinant virus can be isolated in a non-selective medium by the co-expression of e. coli lacz gene. compared with the wild type virus, the tk(-)recombinant spv showed a modest ... | 2001 | 11311343 |
| descriptive epidemiology of a classical swine fever outbreak in the limburg province of belgium in 1997. | this paper describes the epidemiological characteristics of the 1997 classical swine fever (csf) outbreak that occurred in the limburg province of belgium, where there is a policy of non-vaccination, intensive surveillance and eradication. between 30 june and 17 july 1997, eight herds, located in three different areas, were confirmed to be csf-positive. csf virus was transmitted from the primary infected herd of one area to another five herds in the same area and to one herd in a different area. ... | 2001 | 11315525 |
| aggresomes resemble sites specialized for virus assembly. | the large cytoplasmic dna viruses such as poxviruses, iridoviruses, and african swine fever virus (asfv) assemble in discrete perinuclear foci called viral factories. factories exclude host proteins, suggesting that they are novel subcellular structures induced by viruses. novel perinuclear structures, called aggresomes are also formed by cells in response to misfolded protein (johnston, j.a., c.l. ward, and r.r. kopito. 1998. j. cell biol. 143:1883--1898; garcía-mata, r., z. bebök, e.j. sorsche ... | 2001 | 11331297 |
| the influence of downstream protein-coding sequence on internal ribosome entry on hepatitis c virus and other flavivirus rnas. | some studies suggest that the hepatitis c virus (hcv) internal ribosome entry site (ires) requires downstream 5' viral polyprotein-coding sequence for efficient initiation of translation, but the role of this rna sequence in internal ribosome entry remains unresolved. we confirmed that the inclusion of viral sequence downstream of the aug initiator codon increased ires-dependent translation of a reporter rna encoding secretory alkaline phosphatase, but found that efficient translation of chloram ... | 2001 | 11345437 |
| classical swine fever virus (c strain) distribution in organ samples of inoculated piglets. | enzyme linked immunosorbent assays (elisas) and a nested polymerase chain reaction after reverse transcription (rt-pcr) were used for the detection of the chinese strain (c strain) of classical swine fever virus (csfv) in blood and tissue samples of experimentally inoculated piglets. one group of 10 piglets was inoculated with c strain material from rabbits and a second one with material from infected minipig kidney (mpk) cell culture. tested blood samples were taken on the day of inoculation as ... | 2001 | 11356313 |
| [detection of infection with classical swine fever virus in wild boar: a comparison of different laboratory diagnostic methods]. | the aim of this study was to evaluate two commercially available elisas for routine diagnosis of classical swine fever virus (csfv) in wild boar. for this, 222 tissue samples from wild boar were tested in the elisas and the results were compared to those obtained using standard methods. first, frozen spleen sections were examined by direct immunofluorescence, and organ suspensions were prepared and tested for csfv antigen samples were simultaneously examined with the chekit-elisa (dr. bommeli ag ... | 2001 | 11367881 |
| induction of apoptosis in bone marrow neutrophil-lineage cells by classical swine fever virus. | the pathogenesis of bone marrow atrophy during classical swine fever (csf) was investigated in vitro by using csf virus (csfv) infection of bone marrow haematopoietic cells (bmhc). the monocytic lineage had the highest susceptibility to csfv infection, whereas the more mature swc8(+) granulocytic cells were not directly susceptible to infection. however, myelomonocytic precursors were targets for csfv infection and continued to differentiate into swc8(+) granulocytic cells, which remained infect ... | 2001 | 11369874 |
| highly sensitive one-tube rt-pcr and microplate hybridisation assay for the detection and for the discrimination of classical swine fever virus from other pestiviruses. | rapid, sensitive and specific laboratory diagnostic methods are necessary to confirm outbreaks of classical swine fever. the detection of classical swine fever virus (csfv) and its discrimination from other pestiviruses can be achieved by virus isolation on cell culture, antigen detection, or molecular methods. to reduce the time and the number of steps in the diagnostic procedure a sensitive and rapid detection method based on specific amplification of the pestiviral rna by one-step reverse tra ... | 2001 | 11377717 |
| [phylogenetic analysis of swine fever virus strains]. | amplification of h-gene fragment in combination with cdna nucleotide sequencing can be used for indication and strain differentiation of classical swine fever virus. | 2001 | 11392970 |
| oral immunization of pigs against classical swine fever. course of the disease and virus transmission after simultaneous vaccination and infection. | the efficacy of simultaneous vaccination of pigs against classical swine fever (csf) and challenge was evaluated. in this study, domestic weanling pigs were vaccinated orally with a conventional live virus vaccine based on csf virus (csfv) c strain and were challenged simultaneously with csfv of different virulence. all the animals vaccinated and challenged with a high dose of highly virulent koslov strain died while three of five animals challenged with a low dose of highly virulent alfort 187 ... | 2001 | 11394574 |
| effects of classical swine fever virus infection on the porcine leukocyte subsets. | the effects of classical swine fever (csf) virus infection on the porcine leukocyte subsets were investigated by flow cytometry in acute, chronic and convalescent forms of the disease. the virus antigen could be first detected in the monocytes on postinfection (p.i.) day 10 while in the lymphocytes on p.i. day 13. it could be established that the ratio of cd6+ cells decreased until p.i. day 6, but afterwards it started to increase and reached different values. the cd4+cd8+, the cd8+ and the cd6- ... | 2000 | 11402673 |
| evaluation of vaccine-induced maternal immunity against classical swine fever. | the vaccine-induced maternal immunity against classical swine fever (csf) was investigated in this study. eight sows were vaccinated with the chinese strain of classical swine fever virus (csfv). the length of time between vaccination and farrowing was 167-217 days. milk samples from the front, middle and back udder sections and blood samples were taken from the sows on days 3 and 14 after farrowing. blood samples were obtained from the piglets at the age of 3, 6 and 10 weeks. the antibody level ... | 2001 | 11402686 |
| [differential diagnosis of classical swine fever and border disease: seroepidemiological investigation of a pestivirus infection on a mixed sheep and swine farm]. | during recent years neutralizing antibodies against border disease virus (bdv) were found repeatedly in german pig herds. consequently there was a demand for a differential diagnostic system. a permanent sheep cell line and bdv reference strain moredun were chosen and were applied in a could be used case study. a pestivirus could be isolated from piglets on a mixed farm and was characterised as 'non-classical swine fever' (csf) by using monoclonal antibodies. due to a csf suspicion the pig herd ... | 2001 | 11417380 |
| atypical cilia in the bronchiolar epithelium of pigs experimentally infected with hog cholera virus. | to study the effect of hog cholera virus on the epithelial cells of the bronchiolar mucosa, 12 pigs were inoculated with a highly virulent strain. immunohistochemical and ultrastructural examination of the ciliated epithelial cells demonstrated an increase in the number of atypical cilia. the latter showed alterations in the microtubular pattern, possibly resulting from viral interference with the normal metabolism of the epithelial cells. | 2001 | 11428186 |
| transovarial transmission of african swine fever virus in the argasid tick ornithodoros moubata. | the aim of this study was to determine filial infection prevalence of experimentally infected colony ornithodoros moubata walton (ixodoidea: argasidae) ticks for african swine fever virus (asfv). three groups of ticks were used: an uninfected control group, one group orally infected with the vic t90/1 isolate and another group orally infected with the liv 13/33 isolate of asfv. the results show that filial infection prevalences were not constant but were highly variable between egg batches from ... | 2001 | 11434547 |
| african swine fever virus structural protein pe120r is essential for virus transport from assembly sites to plasma membrane but not for infectivity. | this report examines the role of african swine fever virus (asfv) structural protein pe120r in virus replication. immunoelectron microscopy revealed that protein pe120r localizes at the surface of the intracellular virions. consistent with this, coimmunoprecipitation assays showed that protein pe120r binds to the major capsid protein p72. moreover, it was found that, in cells infected with an asfv recombinant that inducibly expresses protein p72, the incorporation of pe120r into the virus partic ... | 2001 | 11435554 |
| classical swine fever: pathogenesis of glomerular damage and immunocharacterization of immunocomplex deposits. | twenty-six pigs were inoculated with a virulent isolate (quillota strain) of classical swine fever (hog cholera) virus to determine the chronological development of lesions in the renal glomeruli and the pathogenesis of glomerular damage and immunocomplex deposition. the study included the use of histopathological, ultrastructural and immunohistochemical (detection of viral antigen gp55, myeloid-histiocyte antigen, igm, igg and c1q) techniques. the main changes in glomerular structure were obser ... | 2001 | 11437500 |
| classical swine fever: morphological and morphometrical study of pulmonary intravascular macrophages. | to gain further insight into the pathogenesis of classical swine fever (csf), the changes induced by hog cholera (hc) virus in pulmonary intravascular macrophages (pims) were examined. twelve pigs were inoculated by the intramuscular route with a virulent strain of hc virus (quillota strain) and killed in groups of three at 4, 7, 10 and 14 days post-inoculation. immunohistochemical and ultrastructural examination revealed hc virus infection in endothelial cells, pims, and interstitial and alveol ... | 2001 | 11437510 |
| [african swine fever virus: achievements over the last decade of the 20th century]. | complete nucleotide sequence of african swine fever (asf) virus genome was determined in 1993-1999. deletion mutants with low virulence for pigs were obtained. genes of structural (p72, p54, p12, cleavage products pp220 and pp60, hemagglutinin) and nonstructural (p32) proteins were mapped. the significance of different proteins in virus adsorption and resistance to challenge was elucidated, their location in infected cell and virion was determined. lipid composition of the virus was studied. a p ... | 2001 | 11449798 |
| [genetic typing of german isolates of classical swine fever virus]. | during the last decade several outbreaks of classical swine fever (csf) occurred in germany in domestic pigs and in wild boar, respectively. two major epidemics which also affected other eu member states were recorded. to support epidemiological investigations genetic typing was applied and virus isolates originating from different outbreaks in germany were assigned to groups and virus types. two genomic regions were selected for the phylogenetic analysis, namely 150 nucleotides from the 5' non- ... | 2001 | 11449911 |
| a virally encoded chaperone specialized for folding of the major capsid protein of african swine fever virus. | it is generally believed that cellular chaperones facilitate the folding of virus capsid proteins, or that capsid proteins fold spontaneously. here we show that p73, the major capsid protein of african swine fever virus (asfv) failed to fold and aggregated when expressed alone in cells. this demonstrated that cellular chaperones were unable to aid the folding of p73 and suggested that asfv may encode a chaperone. an 80-kda protein encoded by asfv, termed the capsid-associated protein (cap) 80, b ... | 2001 | 11461995 |
| isolation of a non-haemadsorbing, non-cytopathic strain of african swine fever virus in madagascar. | african swine fever (asf) suspected clinically in madagascar (1998-9) was confirmed by polymerase chain reaction (pcr) and nucleotide sequencing, following virus isolation. no haemadsorption or cytopathic effect could be detected following leukocyte inoculation, but viral growth in cells was confirmed by pcr. detection of asf virus genome was carried out by amplification of a highly conserved region coding for the p72 protein. nucleotide sequencing of the amplicon revealed 99.2% nucleotide ident ... | 2001 | 11467803 |
| application of competitive enzyme-linked immunosorbent assay for the serologic diagnosis of classical swine fever virus infection. | a competitive enzyme-linked immunosorbent assay (c-elisa), based on a truncated e2 recombinant protein of the alfort/187 strain of classical swine fever virus (csfv) and a specific monoclonal antibody m1669, was evaluated using 2,000 sera from clinically healthy pigs in canada (a csfv-free country) and sera from experimentally infected pigs. the relative specificity and sensitivity of the c-elisa were 100% and 86%, respectively, at a cutoff of 25% inhibition using negative and positive pig sera, ... | 2001 | 11478613 |
| characterization of pseudotype vsv possessing hcv envelope proteins. | the genome of hepatitis c virus (hcv) encodes two envelope glycoproteins (e1 and e2), which are thought to be responsible for receptor binding and membrane fusion resulting in virus penetration. to investigate cell surface determinants important for hcv infection, we used a recombinant vesicular stomatitis virus (vsv) in which the glycoprotein gene was replaced with a reporter gene encoding green fluorescent protein (gfp) and produced hcv-vsv pseudotypes possessing chimeric hcv e1 or e2 glycopro ... | 2001 | 11485395 |
| evidence for the presence of two novel pestivirus species. | the genus pestivirus of the family flaviviridae comprises four species, namely bovine viral diarrhea virus-1 (bvdv-1), bvdv-2, border disease virus (bdv), and classical swine fever virus (csfv). comparative analyses of partial sequences have suggested that pestivirus isolates from giraffe (giraffe-1) and reindeer (reindeer-1) are distinct from the established species (becher et al., virology 262, 64--71, 1999). in this study, we report the complete genomic sequences of pestivirus strains giraffe ... | 2001 | 11485413 |
| novel virulence and host range genes of african swine fever virus. | current work is beginning to reveal the complex mechanisms by which african swine fever virus interacts with its swine and tick hosts. this work includes the identification of novel viral genes that mediate virulence and host range, and influence important cellular regulatory pathways. | 2001 | 11495811 |
| characterization of classical swine fever virus associated with defective interfering particles containing a cytopathogenic subgenomic rna isolated from wild boar. | classical swine fever virus (csfv) strain wb82, isolated from a wild boar in 1982, induced a distinct cytopathic effect (cpe) in primary swine testicle cell culture and in most of the porcine cell lines. this strain of csfv was found to be composed of two biotypes. cytopathogenic (cp) csfv, as a minor population, and noncytopathogenic (noncp) csfv, as a major population. the noncp csfv (designated strain wb82/e+) was obtained by biological cloning, and it showed the exaltation of newcastle disea ... | 2001 | 11503902 |
| classical swine fever (csf): a historical review of research and vaccine production on the isle of riems. | a review on classical swine fever (csf) research and vaccine production is given about four historical periods (1924-1948, 1949-1969, 1970-1991, since 1992). similar as to research on foot and mouth disease, applied topics as diagnosis, pathogenesis, epidemiology and control represented the csf research over many years. the development of vaccines and application procedures, e.g. oral and aerogenic immunisation and combined vaccines for large pig farms were the prominent investigations between 1 ... | 2001 | 11505796 |
| oral immunisation against classical swine fever (csf): onset and duration of immunity. | in an experimental study, onset and duration of immunity after oral immunisation of pigs with a classical swine fever (csf) live virus vaccine based on the strain "c" has been evaluated. sixteen weaner piglets (group 1) were orally instilled by syringe with the content of one vaccine bait whereas eighteen piglets (group 2) were fed with one bait. six unvaccinated piglets represented the control group (group 3). the pigs having 2, 4, 6 and 10 days post vaccination (p.v.) were challenged with the ... | 2001 | 11506924 |
| mutagenesis of hepatitis c virus e1 protein affects its membrane-permeabilizing activity. | the e1 glycoprotein of hepatitis c virus is a transmembrane glycoprotein with a c-terminal anchor domain. when expressed in escherichia coli, e1 induces a change in membrane permeability that is toxic to the bacterial cell. the c-terminal hydrophobic region (aa 331-383) of e1 is mainly responsible for membrane association and for inducing changes in membrane permeability. these observed changes are similar to those produced in e. coli by influenza virus m2, human immunodeficiency virus gp41 and ... | 2001 | 11514735 |
| evaluation of the potential of dogs, cats and rats to spread classical swine fever virus. | | 2001 | 11548961 |
| a recombinant classical swine fever virus with a marker insertion in the internal ribosome entry site. | based on an infectious cdna clone of classical swine fever virus (csfv) strain alfort/187 (ruggli et al., j virol 70, 3478-3487, 1996) a full-length cdna was constructed harbouring a nonviral 44 base insertion in the internal ribosome entry site (ires) within the 5' nontranslated region (5'ntr) of the genome. genome size rna transcribed in vitro served as a positive control in routine rt-pcr used to detect csfv rna in diagnostic material. unexpectedly this rna proved to be infectious upon transf ... | 2001 | 11556403 |
| attenuated lapinized chinese strain of classical swine fever virus: complete nucleotide sequence and character of 3'-noncoding region. | the complete nucleotide sequence including precise 5'- and 3'-terminal non-coding regions (ncrs) of the attenuated lapinized chinese strain (hclv) of classical swine fever virus (csfv) was determined from overlapping cdna clones constructed by separated rt-pcr and rapid amplification of cdna ends (race) methods. the genomic rna of the hclv strain consists of 12.310 nucleotides (nts) including 374 nts and 242nts in the 5'- and 3'-ncrs, respectively. it contains one large open reading frame (orf) ... | 2001 | 11556404 |
| classical swine fever (csf) marker vaccine. trial i. challenge studies in weaner pigs. | two commercial marker vaccines against classical swine fever virus (csfv) and companion diagnostic tests were examined in 160 conventional pigs. to test the vaccines in a "worst case scenario", group of 10 weaners were vaccinated using a single dose of an e2 (gp55) based vaccine at days -21, -14, -10 or -7, and subsequently challenged at day 0. the challenge virus was csfv 277, originating from a recent outbreak of classical swine fever (csf) in germany. in all groups, only 5 out of 10 pigs were ... | 2001 | 11557151 |
| classical swine fever (csf) marker vaccine. trial ii. challenge study in pregnant sows. | the efficacy of two marker vaccines against classical swine fever (csf) was tested in a large scale laboratory trial in several national swine fever laboratories (nsfl) of the eu member states. the vaccines were: bayovac csf marker (vaccine a) from bayer, leverkusen, germany and porcilis pesti (vaccine b) from intervet, boxmeer, the netherlands. at the nsfl of belgium, the netherlands and germany experiments were carried out to examine the ability of the vaccines to prevent transplacental transm ... | 2001 | 11557152 |
| classical swine fever (csf) marker vaccine. trial iii. evaluation of discriminatory elisas. | the objective of the marker vaccine trial was to test the two available csf marker vaccines in scenarios which are likely to occur in the field and to evaluate the reliability of the discriminatory tests. the evaluation of the discriminatory tests was of special importance because there is no requirement for formal data concerning their performance by the european medicinal products evaluation agency (emea) in london. emea is responsible for the licensing procedure of the marker vaccines within ... | 2001 | 11557153 |
| interaction of classical swine fever virus with membrane-associated heparan sulfate: role for virus replication in vivo and virulence. | passage of native classical swine fever virus (csfv) in cultured swine kidney cells (sk6 cells) selects virus variants that attach to the surface of cells by interaction with membrane-associated heparan sulfate (hs). a ser-to-arg change in the c terminus of envelope glycoprotein e(rns) (amino acid 476 in the open reading frame of csfv) is responsible for selection of these hs-binding virus variants (m. m. hulst, h. g. p. van gennip, and r. j. m. moormann, j. virol. 74:9553-9561, 2000). in this i ... | 2001 | 11559790 |
| african swine fever virus protein p54 interacts with the microtubular motor complex through direct binding to light-chain dynein. | dynein is a minus-end-directed microtubule-associated motor protein involved in cargo transport in the cytoplasm. african swine fever virus (asfv), a large dna virus, hijacks the microtubule motor complex cellular transport machinery during virus infection of the cell through direct binding of virus protein p54 to the light chain of cytoplasmic dynein (lc8). interaction of p54 and lc8 occurs both in vitro and in cells, and the two proteins colocalize at the microtubular organizing center during ... | 2001 | 11559815 |
| an e2 sub-unit marker vaccine does not prevent horizontal or vertical transmission of classical swine fever virus. | an experimental infection with classical swine fever (csf) virus in e2 sub-unit marker vaccine vaccinated gilts was conducted in order to evaluate the effect of vaccination on virus transmission and course of the disease. therefore, clinical signs as well as horizontal and vertical virus transmission were monitored in two inoculated, non-vaccinated and 10 vaccinated conventional gilts, housed in individual sow boxes. within 10 days post-inoculation, all vaccinated gilts became infected. dependin ... | 2001 | 11567750 |
| molecular epidemiology of classical swine fever in italy. | to gain an insight into the molecular epidemiology of classical swine fever (csf) in italy, virus isolates originating from outbreaks that occurred between 1985 and 2000 in wild boar or in domestic pigs in mainland italy and in sardinia were analysed by genetic typing. for this, a fragment (190 nucleotides) of the e2 glycoprotein gene was sequenced and phylogenetic analyses were performed, including older italian isolates and isolates from recent outbreaks in europe for comparison. the results s ... | 2001 | 11574170 |
| morphological and immunohistochemical changes in splenic macrophages of pigs infected with classical swine fever. | classical swine fever (csf) was induced in 20 pigs by inoculation with a virulent strain of csf virus to determine sequential changes (2, 4, 7, 10 and 14 days post-inoculation) in the number and morphology of splenic macrophages (red pulp and lymphoid marginal zone) and thus to assess the role of these cells in the pathogenesis of the disease. the first splenic cells to be infected with csf virus were macrophages in the marginal zone followed by other macrophage populations. the initial phase of ... | 2001 | 11578124 |
| evaluation of diagnostic tests for the detection of classical swine fever in the field without a gold standard. | knowledge of the sensitivity of diagnostic tests for infectious diseases under field conditions can be used to design a surveillance program that increases the effectiveness of the control policy. in this study, the sensitivity of tests for the detection of classical swine fever (csf) virus (csfv) under field conditions was estimated without knowledge of the true disease status of the animals tested. during the csf epidemic of 1997-1998 in the netherlands, tonsil samples from pigs of csf suspect ... | 2001 | 11580058 |
| african swine fever virus infection of porcine aortic endothelial cells leads to inhibition of inflammatory responses, activation of the thrombotic state, and apoptosis. | african swine fever (asf) is an asymptomatic infection of warthogs and bushpigs, which has become an emergent disease of domestic pigs, characterized by hemorrhage, lymphopenia, and disseminated intravascular coagulation. it is caused by a large icosohedral double-stranded dna virus, african swine fever virus (asfv), with infection of macrophages well characterized in vitro and in vivo. this study shows that virulent isolates of asfv also infect primary cultures of porcine aortic endothelial cel ... | 2001 | 11581405 |
| erns protein of pestiviruses. | | 2001 | 11586914 |
| factors associated with the introduction of classical swine fever virus into pig herds in the central area of the 1997/98 epidemic in the netherlands. | a matched case-control study of 135 infected and 99 uninfected pig herds from the central area of the 1997 to 1998 epidemic of classical swine fever (csf) in the netherlands was undertaken to identify factors associated with the introduction of the virus. the herds were matched on the basis of herd type and the shortest geographical distance between pairs of herds. data on management, hygienic measures, experiences during the depopulation of an infected nearest neighbour, and the frequency of co ... | 2001 | 11601514 |
| functional properties of a monoclonal antibody inhibiting the hepatitis c virus rna-dependent rna polymerase. | the hepatitis c virus (hcv) rna-dependent rna polymerase (rdrp), represented by nonstructural protein 5b (ns5b), has recently emerged as a promising target for antiviral intervention. here, we describe the isolation, functional characterization, and molecular cloning of a monoclonal antibody (mab) inhibiting the hcv rdrp. this mab, designated 5b-12b7, binds with high affinity to a conformational epitope in the palm subdomain of the hcv rdrp and recognizes native ns5b expressed in the context of ... | 2002 | 11641406 |
| the effect of vaccination with the pav-250 strain classical swine fever (csf) virus on the airborne transmission of csf virus. | the airborne transmission of classical swine fever (csf) virus to susceptible pigs, as well as the effect of vaccination with the csf virus pav-250 strain was investigated on this mode of transmission. experiment i: four pigs were inoculated with the ald csfv strain (10(4.3) 50% tcid) by the intramuscular route, and at the onset of fever, they were introduced into an enclosed chamber. at the end of the experiment surviving pigs were sedated, anesthetized and euthanatized. experiment ii: four pig ... | 2001 | 11642288 |
| phylogenetic comparison of classical swine fever virus in china. | an n-terminal fragment of the e2 gene of classical swine fever (csf) virus encoding major immunogenic sites was amplified by rt-pcr directly from 110 clinical specimens representing 109 epizootic sites during the last decade in china. phylogenetic relationships between these viruses as well as 20 reference strains were determined by comparison of their nucleotide sequences. a phylogenetic tree showed that 103 of the 110 field viruses (93.6%) were clustered within group 2 and subdivided into thre ... | 2001 | 11682122 |
| lipopolysaccharide-induced impairment of classical swine fever virus infection in monocytic cells is sensitive to 2-aminopurine. | lipopolysaccharide (lps) impairs classical swine fever virus (csfv) replication in monocytic cells, which are primary targets for csfv and mediators of virus-induced immunomodulation. although soluble antiviral factors including interferons (ifn) were not detected, ifn-alpha and ifn-beta mrna were induced. the serine threonine protein kinase inhibitor 2-aminopurine, impeded this antiviral activity. these results indicate that the lps-induced antiviral state employs signaling pathways, in which t ... | 2002 | 11684317 |
| solution structure of a viral dna repair polymerase. | dna polymerase x (pol x) from the african swine fever virus (asfv) specifically binds intermediates in the single-nucleotide base-excision repair process, an activity indicative of repair function. in addition, pol x catalyzes dna polymerization with low nucleotide-insertion fidelity. the structural mechanisms by which dna polymerases confer high or low fidelity in dna polymerization remain to be elucidated. the three-dimensional structure of pol x has been determined. unlike other dna polymeras ... | 2001 | 11685238 |
| solution structure of a viral dna polymerase x and evidence for a mutagenic function. | the african swine fever virus dna polymerase x (asfv pol x or pol x), the smallest known nucleotide polymerase, has recently been reported to be an extremely low fidelity polymerase that may be involved in strategic mutagenesis of the viral genome. here we report the solution structure of pol x. the structure, unique within the realm of nucleotide polymerases, consists of only palm and fingers subdomains. despite the absence of a thumb subdomain, which is important for dna binding in other polym ... | 2001 | 11685239 |
| epitope mapping and affinity purification of monospecific antibodies by escherichia coli cell surface display of gene-derived random peptide libraries. | we report a method for the precise mapping of linear epitopes by presenting a peptide library on the surface of escherichia coli cells. a random library of gene fragments derived from the classical swine fever virus (csfv) envelope protein e(rns) was generated by dnase i cleavage and cloned into a specially designed bacterial surface display vector. a carboxyterminally truncated intimin, an adhesin from enteropathogenic e. coli, serves as a carrier protein to present foreign peptides on the surf ... | 2001 | 11687250 |
| the trans golgi network is lost from cells infected with african swine fever virus. | the cellular secretory pathway is important during the assembly and envelopment of viruses and also controls the transport of host proteins, such as cytokines and major histocompatibility proteins, that function during the elimination of viruses by the immune system. african swine fever virus (asfv) encodes at least 26 proteins with stretches of hydrophobic amino acids suggesting entry into the secretory pathway (r. j. yanez, j. m. rodriguez, m. l. nogal, l. yuste, c. enriquez, j. f. rodriguez, ... | 2001 | 11689656 |
| antigenic and immunogenic properties of a chimera of two immunodominant african swine fever virus proteins. | a chimera of the two immunodominant african swine fever (asf) virus proteins p54 and p30 was constructed by insertion of the gene cp204l into a not i restriction site of e183l gene. the resulting chimeric protein p54/30, expressed by a recombinant baculovirus in insect cells and in trichoplusia ni larvae, retained antigenic determinants present in both proteins and reacted in western blot with a collection of sera from inapparent asf virus carrier pigs. remarkably, pigs immunized with the chimer ... | 2001 | 11699955 |
| oral and sub-cutaneous vaccination of commercial pigs with a recombinant porcine adenovirus expressing the classical swine fever virus gp55 gene. | a recombinant porcine adenovirus expressing the classical swine fever virus (csfv) gp55/e2 gene was administered to commercially available pigs via oral or subcutaneous routes and their susceptibility to oral and subcutaneous challenge with csfv was determined. 100% of animals vaccinated and challenged subcutaneously were protected. in the groups of pigs vaccinated either orally or subcutaneously and then challenged orally, 60% of animals were protected. before challenge, neutralising antibodies ... | 2001 | 11699963 |
| adsorption of colostral antibodies against classical swine fever, persistence of maternal antibodies, and effect on response to vaccination in baby pigs. | to determine kinetics of antibody absorption, persistence of antibody concentrations, and influence of titers on vaccination of baby pigs with a vaccine against classical swine fever (csf). | 2001 | 11703028 |
| an experimental infection with classical swine fever virus in pregnant sows: transmission of the virus, course of the disease, antibody response and effect on gestation. | an experimental infection with classical swine fever (csf) virus in 12 conventional gilts, housed in a sow-box housing system, was conducted in order to evaluate horizontal transmission, clinical, virological and serological response, and the effect on gestation. two of the 12 gilts, of which 10 were pregnant, were experimentally inoculated. they became viraemic for the first time 6 days post-inoculation (dpi). the contact gilts became viraemic between 18 and 21 days post inoculation. on the bas ... | 2001 | 11708677 |
| are low-density granulocytes the major target cells of classical swine fever virus in the peripheral blood? | the target cells of classical swine fever (csf) virus in the peripheral blood of pigs infected with recent field isolates from germany were studied. eight weaned pigs were inoculated oronasally with the csf virus field isolate visbek/han 95 and three weaners were inoculated with the isolate losten/freese 98. all pigs showed severe clinical signs typical of csf and died or had to be euthanized between 9 and 24 days post-infection (dpi). the first cells in the peripheral blood which became infecte ... | 2001 | 11708678 |
| the ns5a protein of bovine viral diarrhoea virus interacts with the alpha subunit of translation elongation factor-1. | a cellular protein that interacts with the ns5a polypeptide of bovine viral diarrhoea virus (bvdv) was identified in a yeast two-hybrid screen. the ns5a interactor was identified as the alpha subunit of bovine translation elongation factor 1a (eef1a). cell-free binding studies were performed with chimeric ns5a fused to glutathione s-transferase (gst-ns5a) expressed in bacteria. gst-ns5a bound specifically to both in vitro-translated and mammalian cell-expressed eef1a. moreover, purified eef1a bo ... | 2001 | 11714969 |
| cloning and sequencing of full-length cdna of classical swine fever virus lpc strain. | the cdnas of classical swine fever virus (lpc vaccine strain) were cloned by transcriptase-polymerase chain reaction, and their nucleotide sequences were determined. in this work, we obtained the sequence information of the 786 bases of the 5'-terminal region, 6049 bases of the middle region, and 1648 bases of the 3'-terminal region. taking our previous results and present data together, the entire genomic sequence of lpc strain was completed (12344 nucleotides in length). the genome of lpc has ... | 2001 | 11724273 |
| 1h, 15n, and 13c resonance assignments for a 20 kda dna polymerase from african swine fever virus. | | 2001 | 11727982 |
| mechanism of interferon resistance in hepatitis c. | | 2001 | 11728538 |
| the correlation of virus-specific interferon-gamma production and protection against classical swine fever virus infection. | the level of antigen-specific interferon-gamma (ifn-gamma) production can be used as an indicator of cellular immunity. in this study, we investigated the role of cellular immune response in protection against classical swine fever virus (csfv). pigs were vaccinated once with csfv vaccine and challenged 6 days post-vaccination (dpv). vaccinated animals had significantly higher csfv-specific ifn-gamma secreting cells than the unvaccinated pigs (p<0.05) at the time of challenge and were protected ... | 2001 | 11730928 |
| a serodiagnostic elisa using recombinant antigen of swine transmissible gastroenteritis virus nucleoprotein. | a serodiagnostic elisa utilizing the recombinant nucleoprotein (rn protein) of transmissible gastroenteritis virus (tgev) was developed, and evaluated by examining a panel of 141 virus neutralization (vn) positive and 101 negative sera. the rn protein-based elisa (rnelisa) appeared to be highly sensitive and specific (98.6% and 98.0%, respectively) when it was compared to the vn test. the result was similar to that of an elisa based on purified viral antigens with showing good correlation (r=0.8 ... | 2001 | 11767065 |
| the g5r (d250) gene of african swine fever virus encodes a nudix hydrolase that preferentially degrades diphosphoinositol polyphosphates. | the african swine fever virus (asfv) g5r gene encodes a protein containing a nudix hydrolase motif which in terms of sequence appears most closely related to the mammalian diadenosine tetraphosphate (ap4a) hydrolases. however, purified recombinant g5r protein (g5rp) showed a much wider range of nucleotide substrate specificity compared to eukaryotic ap4a hydrolases, having highest activity with gtp, followed by adenosine 5'-pentaphosphate (p5a) and dgtp. diadenosine and diguanosine nucleotides w ... | 2002 | 11773415 |
| [sero-monitoring of notifiable diseases in wild boar in the netherlands 1999-2001]. | within the framework of a sero-monitoring system, in operation since 1996. blood samples from wild boar shot during the hunting seasons 1999-2000 and 2000-2001 in the netherlands were screened for the presence of antibodies against classical swine fever virus (csfv), swine vesicular disease virus (svdv), and anjeszky's disease virus (adv). the results indicate that csfv, svdv, and adv are uncommon in the wild boar population in the netherlands. because of the recent foot-and-mouth disease (fmd) ... | 2001 | 11780256 |
| a 250-nucleotide ua-rich element in the 3' untranslated region of xenopus laevis vg1 mrna represses translation both in vivo and in vitro. | xenopus laevis vgl mrna undergoes both localization and translational control during oogenesis. vg1 protein does not appear until late stage iv, after localization is complete. to determine whether vg1 translation is regulated by cytoplasmic polyadenylation, the race-pat method was used. vg1 mrna has a constant poly(a) tail throughout oogenesis, precluding a role for cytoplasmic polyadenylation. to identify cis-acting elements involved in vg1 translational control, the vg1 3' utr was inserted do ... | 2001 | 11780632 |
| pathogenesis of african swine fever virus in ornithodoros ticks. | african swine fever virus (asfv) is the only known dna arbovirus and the sole member of the family asfarviridae. it causes a lethal, hemorrhagic disease in domestic pigs. asfv is enzootic in sub-saharan africa and is maintained in a sylvatic cycle by infecting both wild members of the suidae (e.g. warthogs) and the argasid tick ornithodoros porcinus porcinus. the pathogenesis of asfv in o. porcinus porcinus ticks is characterized by a low infectious dose, lifelong infection, efficient transmissi ... | 2001 | 11831434 |
| analysis of the complete nucleotide sequence of african swine fever virus. | we present an analysis of the complete genome of african swine fever virus (asfv) strain ba71v, including 80 kbp of novel sequence and 90 kbp previously reported by several authors. the viral dna is 170,101 nucleotides long and contains 151 open reading frames. structural and/or functional information is available on 113 viral proteins. asfv encodes five multigene families, putative membrane and secreted proteins, and enzymes involved in nucleotide and nucleic acid metabolism (including dna repa ... | 1995 | 11831707 |
| steatosis and liver cancer in transgenic mice expressing the structural and nonstructural proteins of hepatitis c virus. | the aim of this study was to determine whether expression of hepatitis c virus proteins alters hepatic morphology or function in the absence of inflammation. | 2002 | 11832450 |
| identification of t-cell epitopes in the structural and non-structural proteins of classical swine fever virus. | to identify new t-cell epitopes of classical swine fever virus (csfv), 573 overlapping, synthetic pentadecapeptides spanning 82% of the csfv (strain glentorf) genome sequence were synthesized and screened. in proliferation assays, 26 peptides distributed throughout the csfv viral protein sequences were able to induce specific t-cell responses in pbmcs from a csfv-glentorf-infected d/d haplotype pig. of these 26 peptides, 18 were also recognized by pbmcs from a csfv-alfort/187-infected d/d haplot ... | 2002 | 11842250 |
| epidemiology and control of an outbreak of classical swine fever in wild boar in switzerland. | an outbreak of classical swine fever in wild boar in the southern part of switzerland (canton of ticino) was investigated after the implementation of control measures in a defined infected area (the risk zone), and in a surrounding surveillance zone (the non-risk zone). after the disease had been detected, hunting was not allowed in the risk zone for over six months, during which the disease was left to run its course, but hunting was continued in the non-risk zone for one month. after seven mon ... | 2002 | 11842816 |
| method for detection of extraneous active bovine viral diarrhoea virus and classical swine fever virus in animal viral vaccines by rt-pcr, which amplify negative-strand viral rna in infected cells. | an oligonucleotide sense primer, pst324alpha, was designed and used for synthesizing cdna from negative-strand viral rna in infected cells and used for rapid detection of active extraneous bovine viral diarrhoea virus (bvdv) and classical swine fever virus (csfv) in animal viral vaccines by culturing a sample in cells followed by reverse transcriptase-polymerase chain reaction (rt-pcr). active and inactivated viruses of bvdv no. 12-43 strain and csfv gpe(-)strain were inoculated to bovine testic ... | 2002 | 11846427 |
| quantitative assessment of clinical signs for the detection of classical swine fever outbreaks during an epidemic. | the performance of clinical signs as a diagnostic test for the detection of classical swine fever (csf) outbreaks during the 1997-1998 csf epidemic in the netherlands was evaluated by constructing and analysing a receiver operating characteristic (roc) curve. this curve assesses the discriminating ability of a diagnostic test over a range of test signals. the cut-off values for a defined diagnostic test to detect csf outbreaks were set by different combinations of clinical signs observed. the ar ... | 2002 | 11856582 |
| experimental non-transmissible marker vaccines for classical swine fever (csf) by trans-complementation of e(rns) or e2 of csfv. | three mutants with deletions in the e2 gene of the infectious dna copy of the classical swine fever virus (csfv) strain-c were constructed: one missing the b/c domain of csfv-e2 between amino acids (aa) 693 and 746, one missing the a domain between aa 800 and 864, and one missing the complete e2 between aa 689 and 1062. all three csfv-e2 deletion mutants were unable to generate viable virus, indicating that each of the antigenic domains of e2 is essential for viability of csfv. to rescue the csf ... | 2002 | 11858861 |
| repression of african swine fever virus polyprotein pp220-encoding gene leads to the assembly of icosahedral core-less particles. | african swine fever virus (asfv) polyprotein pp220, encoded by the cp2475l gene, is an n-myristoylated precursor polypeptide that, after proteolytic processing, gives rise to the major structural proteins p150, p37, p34, and p14. these proteins localize at the core shell, a matrix-like virus domain placed between the dna-containing nucleoid and the inner envelope. in this study, we have examined the role of polyprotein pp220 in virus morphogenesis by means of an asfv recombinant, v220i, containi ... | 2002 | 11861832 |
| [prediction of recognition sites for genomic replication of classical swine fever virus with information analysis]. | in order to explore the mechanism for the genomic replication of classical swine fever virus (csfv), so as to make a basis for investigating its pathogenicity, an introduction of the information theory is presented in connection with the statistical mechanics, whence small-sample statistics appears naturally as a consequence of the bayesian approach. furthermore, a selection rule for identifying the pattern of a recognition site for an rna-binding protein is proposed by means of the maximum entr ... | 2002 | 11862713 |
| sequences and replication of genomes of the archaeal rudiviruses sirv1 and sirv2: relationships to the archaeal lipothrixvirus sifv and some eukaryal viruses. | the double-stranded dna genomes of the viruses sirv1 and sirv2, which infect the extremely thermophilic archaeon sulfolobus and belong to the family rudiviridae, were sequenced. they are linear, covalently closed at the ends, and 32,312 and 35,502 bp long, respectively, with an a+t content of 75%. the genomes of sirv1 and sirv2 carry inverted terminal repeats of 2029 and 1628 bp, respectively, which contain multiple direct repeats. sirv1 and sirv2 genomes contain 45 and 54 orfs, respectively, of ... | 2001 | 11878892 |
| genetic typing of ruminant pestivirus strains from northern ireland and the republic of ireland. | a study was performed to investigate the genotypes and sub-groups of pestiviruses present in ruminants in ireland. these comprised one ovine and eighteen bovine pestiviruses from northern ireland and six bovine pestiviruses from the republic of ireland. a 288 base pair (bp) portion of the 5'-non coding region (5'-ncr) from each of 25 pestiviruses collected over a period of 31 years was amplified by reverse-transcription-polymerase chain reaction (rt-pcr) and the product directly sequenced. from ... | 2001 | 11883891 |
| novel swine virulence determinant in the left variable region of the african swine fever virus genome. | previously we have shown that the african swine fever virus (asfv) nl gene deletion mutant e70deltanl is attenuated in pigs. our recent observations that nl gene deletion mutants of two additional pathogenic asfv isolates, malawi lil-20/1 and pr4, remained highly virulent in swine (100% mortality) suggested that these isolates encoded an additional virulence determinant(s) that was absent from e70. to map this putative virulence determinant, in vivo marker rescue experiments were performed by in ... | 2002 | 11884534 |
| modeling and real-time prediction of classical swine fever epidemics. | we propose a new method to analyze outbreak data of an infectious disease such as classical swine fever. the underlying model is a two-type branching process. it is used to deduce information concerning the epidemic from detected cases. in particular, the method leads to prediction of the future course of the epidemic and hence can be used as a basis for control policy decisions. we test the model with data from the large 1997-1998 classical swine fever epidemic in the netherlands. it turns out ... | 2002 | 11892689 |
| a single amino acid is critical for the expression of b-cell epitopes on the helicase domain of the pestivirus ns3 protein. | truncated ns3 proteins, expressed by recombinant baculoviruses, were used to investigate the location of conserved b-cell epitopes on this non-structural bovine viral diarrhoea virus (bvdv) protein. a goat anti-pestivirus antiserum, and a panel of anti-ns3 monoclonal antibodies, including the bvdv-1 specific antibody p1d8, were used to verify the presence or absence of the epitopes. interestingly, the monoclonal antibodies reacted only with the truncated protein encompassing the helicase domain ... | 2002 | 11900844 |
| [the contagiousness of the pestivirus and foot and mouth disease virus]. | | 2002 | 11905240 |
| african swine fever virus iap-like protein induces the activation of nuclear factor kappa b. | african swine fever virus (asfv) encodes a homologue of the inhibitor of apoptosis (iap) that promotes cell survival by controlling the activity of caspase-3. here we show that asfv iap is also able to activate the transcription factor nf-kappab. thus, transient transfection of the viral iap increases the activity of an nf-kappab reporter gene in a dose-responsive manner in jurkat cells. similarly, stably transfected cells expressing asfv iap have elevated basal levels of c-rel, an nf-kappab-dep ... | 2002 | 11907233 |
| african swine fever virus-induced polypeptides in porcine alveolar macrophages and in vero cells: two-dimensional gel analysis. | high-resolution two-dimensional electrophoresis followed by computer analysis has been used to study quantitatively the patterns of protein synthesis produced in porcine alveolar macrophages and in vero cells infected with african swine fever virus (asfv). initially, a protein database for each cell type was constructed. the porcine alveolar macrophage database includes 995 polypeptides (818 acidic, isoelectric focusing (ief) and 177 basic, nonequilibrium ph gradient electrophoresis (nephge)) wh ... | 2001 | 11922604 |
| electrochemical characterization of screen-printed carbonaceous electrodes for the determination of peroxidase activity in novel screen-printed flow-through modules. | a novel totally screen-printed flow-through cell for immunoanalysis is presented. it contained screen-printed carbonaceous electrodes, which allowed the determination of peroxidase activity through the electrochemical reduction of p-benzoquinone. as different electrode materials differ strongly in their electrochemical properties, electrodes resulting from various screen-printable carbonaceous pastes were characterized using the hydroquinone/ p-benzoquinone redox couple. for most of the electrod ... | 2002 | 11936093 |
| reconstitution of hepatitis c virus envelope glycoproteins into liposomes as a surrogate model to study virus attachment. | the envelope glycoproteins, e1 and e2, of hepatitis c virus (hcv) assemble intracellularly to form a noncovalent heterodimer that is expected to be essential for viral assembly and entry. however, due to the lack of a cell culture system supporting efficient hcv replication, it is very difficult to obtain relevant information on the functions of this glycoprotein oligomer. to get better insights into its biological and biochemical properties, hcv envelope glycoprotein heterodimer expressed by a ... | 2002 | 11937498 |
| development of a rapid in vitro protein refolding assay which discriminates between peptide-bound and peptide-free forms of recombinant porcine major histocompatibility class i complex (sla-i). | the extracellular domains of swine leukocyte antigen class i (sla-i, major histocompatibility complex protein class i) were cloned and sequenced for two haplotypes (h4 and h7) which do not share any alleles based on serological typing, and which are the most important in danish farmed pigs. the extracellular domain of sla-i was connected to porcine beta2 microglobulin by glycine-rich linkers. the engineered single-chain proteins, consisting of fused sla-i and beta2 microglobulin, were overexpres ... | 2002 | 11943330 |
| orf virus encodes a functional dutpase gene. | the present study is the first report on the functional activity of a parapoxvirus-encoded dutpase. the dutpase gene of the attenuated orf virus (orfv), strain d1701, was expressed as a bacterial thioredoxin fusion protein. in vitro assays showed that orfv dutpase was highly specific for dutp as substrate. the enzyme was active over a broad ph range (ph 6.0-9.0), with maximal enzymatic activity at ph 7.0 in the presence of mg(2+) cations. kinetic studies of the recombinant orfv dutpase revealed ... | 2002 | 11961258 |
| pestivirus internal ribosome entry site (ires) structure and function: elements in the 5' untranslated region important for ires function. | the importance of certain structural features of the 5' untranslated region of classical swine fever virus (csfv) rna for the function of the internal ribosome entry site (ires) was investigated by mutagenesis followed by in vitro transcription and translation. deletions made from the 5' end of the csfv genome sequence showed that the ires boundary was close to nucleotide 65: thus, the ires includes the whole of domain ii but no sequences upstream of this domain. deletions which invaded domain i ... | 2002 | 11967318 |
| rate of inter-herd transmission of classical swine fever virus by different types of contact during the 1997-8 epidemic in the netherlands. | in this study we quantified the rate at which classical swine fever had been transmitted by several different types of inter-herd contact during the 1997-8 epidemic in the netherlands. during that epidemic 428 csfv-infected pig herds were detected, 403 of which were include in this study. the estimated rates of transmission were 0.065 per shipment of live pigs, 0.011 per contact by a pig transportation lorry, 0.0068 per person contact, 0.0007 per dose of semen, 0.0065 per contact with a potentia ... | 2002 | 12002547 |
| within- and between-pen transmission of classical swine fever virus: a new method to estimate the basic reproduction ratio from transmission experiments. | we present a method to estimate basic reproduction ratio r0 from transmission experiments. by using previously published data of experiments with classical swine fever virus more extensively, we obtained smaller confidence intervals than the martingale method used in the original papers. moreover, our method allows simultaneous estimation of a reproduction ratio within pens r0w and a modified reproduction ratio between pens r'0b. resulting estimates of r0w and r'0b for weaner pigs were 100 (95% ... | 2002 | 12002548 |