Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| [detection of equine arteritis virus (eav) in stallions--a contribution to the improvement of eav diagnosis]. | serum samples from 72 stallions were examined for the occurrence of antibodies against equine arteritis virus, of which 41 animals (57%) were found to be positive. 32 of the seropositive stallions were then screened for persistent eav infection, before and after the breeding season. semen samples were investigated by rt-pcr followed by dot blot hybridization and nested pcr, and by virus isolation on cell cultures as well. the carrier state was virologically confirmed in 11 of 32 stallions (34%) ... | 1999 | 10028725 |
| proteolytic processing of the open reading frame 1b-encoded part of arterivirus replicase is mediated by nsp4 serine protease and is essential for virus replication. | the open reading frame (orf) 1b-encoded part of the equine arteritis virus (eav) replicase is expressed by ribosomal frameshifting during genome translation, which results in the production of an orf1ab fusion protein (345 kda). four orf1b-encoded processing products, nsp9 (p80), nsp10 (p50), nsp11 (p26), and nsp12 (p12), have previously been identified in eav-infected cells (l. c. van dinten, a. l. m. wassenaar, a. e. gorbalenya, w. j. m. spaan, and e. j. snijder, j. virol. 70:6625-6633, 1996). ... | 1999 | 9971783 |
| open reading frame 1a-encoded subunits of the arterivirus replicase induce endoplasmic reticulum-derived double-membrane vesicles which carry the viral replication complex. | the replicase of equine arteritis virus (eav; family arteriviridae, order nidovirales) is expressed in the form of two polyproteins (the open reading frame 1a [orf1a] and orf1ab proteins). three viral proteases cleave these precursors into 12 nonstructural proteins, which direct both genome replication and subgenomic mrna transcription. immunofluorescence assays showed that most eav replicase subunits localize to membranes in the perinuclear region of the infected cell. using replicase-specific ... | 1999 | 9971782 |
| novel endogenous retroviral sequences in the chicken genome closely related to hprs-103 (subgroup j) avian leukosis virus. | hprs-103, the prototype of avian leukosis virus (alv) subgroup j, is a recently identified retrovirus associated with myeloid leukosis in meat-type chickens. although this virus shows high sequence identity to other alv subgroups within the gag and pol genes, its env gene is highly diverged (with only about 40% sequence identity) from other alv subgroups. on the other hand, the sequence of the env gene of hprs-103 was 75% identical to that of e51, a member of the eav family of endogenous avian r ... | 1999 | 9934710 |
| detection of antibodies to equine arteritis virus by enzyme linked immunosorbant assays utilizing g(l), m and n proteins expressed from recombinant baculoviruses. | indirect enzyme linked immunosorbant assays (elisas) utilizing the three major structural proteins (m, n, and g(l)) of equine arteritis virus (eav) expressed from recombinant baculoviruses were developed. a large panel of sera collected from uninfected horses, and from animals experimentally and naturally infected with eav or vaccinated with the modified live virus vaccine against equine viral arteritis, were used to characterize the humoral immune response of horses to the three major eav struc ... | 1998 | 9923747 |
| equine viral arteritis risk from imported semen. | 1998 | 9921633 | |
| serologic and molecular characterization of an abortigenic strain of equine arteritis virus isolated from infective frozen semen and an aborted equine fetus. | a virus isolated from an aborted equine fetus was determined to be antigenically distinct from several other strains of equine arteritis virus (eav) by use of a neutralization assay with a large panel of neutralizing monoclonal antibodies. the virus was readily neutralized by polyclonal equine anti-eav serum. comparative nucleotide and amino acid sequence analyses indicated that the virus (wa97) isolated from the aborted fetus was virtually identical to a virus (s1971) isolated from imported sem ... | 1998 | 9838958 |
| the unique envelope gene of the subgroup j avian leukosis virus derives from ev/j proviruses, a novel family of avian endogenous viruses. | a new subgroup of avian leukosis virus (alv), designated subgroup j, was identified recently. viruses of this subgroup do not cross-interfere with viruses of the avian a, b, c, d, and e subgroups, are not neutralized by antisera raised against the other virus subgroups, and have a broader host range than the a to e subgroups. sequence comparisons reveal that while the subgroup j envelope gene includes some regions that are related to those found in env genes of the a to e subgroups, the majority ... | 1998 | 9811756 |
| enzyme-linked immunosorbent assay for serological survey of equine arteritis virus in racehorses. | to examine antibodies against equine arteritis virus (eav), an enzyme-linked immunosorbent assay (elisa) using purified virus antigen was developed. the results of elisa were compared with those of serum neutralization (sn) tests. the elisa absorbance values and the sn titers in sera collected weekly from eav-infected horses showed a similar pattern. the elisa could detect antibody to eav in horses experimentally infected with not only a homologous virus strain, which was used as the elisa antig ... | 1998 | 9795910 |
| the reverse transcriptase activity in cell-free medium of chicken embryo fibroblast cultures is not associated with a replication-competent retrovirus. | reverse transcriptase (rt) activity has previously been reported in concentrated medium of primary chicken embryo cell cultures using the traditional rt assay. recently, using the newly-developed and highly-sensitive product-enhanced reverse transcriptase (pert) assay, rt activity has been detected in live, attenuated vaccines grown in chicken cell substrates. furthermore, this activity has been associated with particles that contain rna related to an ancient, endogenous avian retrovirus family ... | 1998 | 9784139 |
| genetic variation and phylogenetic analysis of open reading frames 3 and 4 of various equine arteritis virus isolates. | the genetic variation in equine arteritis virus (eav) nonstructural (ns) protein-encoding open reading frames (orf) 3 and 4 genes was investigated. nucleotide and deduced amino acid sequences from seven different eav isolates (one european, one american and five canadian isolates) and the arvac vaccine strain were compared with those of the bucyrus reference strain. orf 3 nucleotide and amino acid sequence identities amongst these isolates (including the arvac vaccine strain) and the bucyrus ref ... | 1998 | 9782363 |
| sequence determination and genetic analysis of the leader region of various equine arteritis virus isolates. | the entire leader sequence of ten equine arteritis virus (eav) isolates including the bucyrus reference strain was determined and analyzed at the primary nucleotide and secondary structure levels. the leader sequence of eight eav isolates was determined to be 206 nucleotides (nt) in length, whereas those of the 86ab-a1 and 86ny-a1 isolates were found to be 205 and 207 nt in length, respectively. the sequence identity of the leader sequences between the different isolates and the bucyrus referenc ... | 1998 | 9782362 |
| equine viral arteritis. current status in finland. | a serological study for antibodies against equine arteritis virus (eav) in finland was performed during 1996. all equine sera delivered to the virology unit at the national veterinary and food research institute were tested with a micro-neutralization test, using the arvac strain as antigen. the study also included imported horses to evaluate eav circulation in the countries of origin. nucleocapsid gene sequences of 2 finnish equine semen isolates were amplified with rt-pcr and sequenced. the ge ... | 1998 | 9782341 |
| the arterivirus replicase. the road from rna to protein(s), and back again. | 1998 | 9782270 | |
| screening of horse polyclonal antibodies with a random peptide library displayed on phage: identification of ligands used as antigens in an elisa test to detect the presence of antibodies to equine arteritis virus. | a random hexapeptide fusion-phage library was screened to isolate phages that bind to antibodies present in horse sera positive for equine arteritis virus (eav). analysis of the peptide sequences displayed by isolated phages identified seven groups. 25% of the isolated phages used as antigens in an elisa test were specifically recognised by a pool of sera which was positive for eav in virus neutralisation test (vn). five of these, when used as antigen in elisa, detected greater than 50% of sera ... | 1998 | 9766888 |
| passive transfer, rate of decay, and protein specificity of antibodies against equine arteritis virus in horses from a standardbred herd with high seroprevalence. | to determine rate of decay of passively acquired antibodies in standardbred foals on a farm with a high seroprevalence to equine arteritis virus (eav) and to determine whether vertical or horizontal transmission of the virus was responsible for infection on the farm. | 1998 | 9743724 |
| retrovirus-induced disease in poultry. | three species of avian retrovirus cause disease in poultry: the avian leukosis/sarcoma virus (alsv), reticuloendotheliosis virus (rev), and lymphoproliferative disease virus (lpdv) of turkeys. the alsv can be classified as slowly transforming viruses, which lack a viral oncogene, and acutely transforming viruses, which possess a viral oncogene. slowly transforming viruses induce late onset leukoses of the b cell lymphoid, erythroid, and myeloid cell lineages, and other tumors, by viral promoter ... | 1998 | 9706091 |
| nucleotide sequence and genetic analysis of the leader region of canadian, american and european equine arteritis virus isolates. | the extreme 5' end, the entire leader sequence of the arvac vaccine strain, and 10 equine arteritis virus (eav) isolates, including the atcc bucyrus reference strain and 5 canadian field isolates, were determined and compared at the primary nucleotide and secondary structure levels. the leader sequence of eight eav isolates, including the bucyrus reference strain, and the leader sequence of the arvac vaccine strain was determined to be 206 nt in length (not including the putative 5' cap structur ... | 1998 | 9684053 |
| serologic response of horses to the structural proteins of equine arteritis virus. | equine arteritis virus (eav) is the causative agent of equine viral arteritis, an apparently emerging disease of equids. in this study, the antibody response of horses to the structural proteins of eav was evaluated using gradient-purified eav virions and baculovirus-expressed recombinant eav structural proteins (g(l), g(s), m, n) as antigens in a western immunoblotting assay. thirty-three sera from horses that previously had been naturally or experimentally infected with eav were evaluated, inc ... | 1998 | 9683071 |
| development and application of polymerase chain reaction (pcr) tests for the detection of subgroup j avian leukosis virus. | subgroup j avian leukosis virus (alv) is a recently identified avian retrovirus associated with myeloid leukosis in meat-type chickens. the env gene of the hprs-103 strain of alv, the prototype of this subgroup, differs considerably from that of other subgroups, but shows close homology to the env-like sequences of members of the eav family of endogenous retroviruses. polymerase chain reaction (pcr) tests using two sets of primers were developed for the specific detection of the members of this ... | 1998 | 9660074 |
| molecular variation in the nucleoprotein gene (orf7) of the porcine reproductive and respiratory syndrome virus (prrsv). | the nucleoprotein gene (orf7) of 15 european isolates of porcine reproductive and respiratory syndrome virus (prrsv) was sequenced and compared with corresponding sequences of other prrsv isolates (2 european and 13 american) and one isolate each of other arteriviruses (the lactate dehydrogenase elevating virus (ldv), the simian haemorrhagic fever virus (shfv) and the equine arteritis virus (eav)). their phylogenetic relationships were established using neighbour-joining and parsimony methods. f ... | 1998 | 9660067 |
| orf1a-encoded replicase subunits are involved in the membrane association of the arterivirus replication complex. | among the functions of the replicase of equine arteritis virus (eav; family arteriviridae, order nidovirales) are important viral enzyme activities such as proteases and the putative rna polymerase and rna helicase functions. the replicase is expressed in the form of two polyproteins (open reading frame 1a [orf1a] and orf1ab), which are processed into 12 nonstructural proteins by three viral proteases. in immunofluorescence assays, the majority of these cleavage products localized to the perinuc ... | 1998 | 9658116 |
| effect of heparin on hemagglutination by equine arteritis virus. | heparin inhibited hemagglutination (ha) by equine arteritis virus (eav) as well as did ha by aujeszky's disease virus (adv), but failed to inhibit ha by parainfluenza virus type 3 (piv-3). the minimal concentration of heparin required to inhibit 8 ha u of eav was 0.1 u/ml. in addition, most eav hemagglutinin was retained by heparin acrylic beads, as was adv hemagglutinin, but was not piv-3 hemagglutinin. mouse erythrocytes failed to combine with the ha inhibitory factor of heparin. however, mous ... | 1998 | 9592716 |
| antigenic variants of j subgroup avian leukosis virus: sequence analysis reveals multiple changes in the env gene. | hprs-103, the prototype of avian leukosis virus (alv) subgroup j, was isolated in 1989 from meat-type chickens from commercial flocks where it induces myelocytic myeloid leukosis (ml). the hprs-103 env gene differs considerably from other alv subgroups but shows high identity (75-97%) to env-like sequences of the different members of the eav family of endogenous avian retroviruses. recently, we have isolated several viruses related to hprs-103 from cases of ml. although these isolates showed pro ... | 1998 | 9568971 |
| a 68-nucleotide sequence within the 3' noncoding region of simian hemorrhagic fever virus negative-strand rna binds to four ma104 cell proteins. | the 3' noncoding region (ncr) of the negative-strand rna [3'(-)ncr rna] of the arterivirus simian hemorrhagic fever virus (shfv) is 209 nucleotides (nt) in length. since this 3' region, designated 3'(-)209, is the site of initiation of full-length positive-strand rna and is the template for the synthesis of the 5' leader sequence, which is found on both full-length and subgenomic mrnas, it is likely to contain cis-acting signals for rna synthesis and to interact with cellular and viral proteins ... | 1998 | 9557724 |
| venereal infection of mares by equine arteritis virus and use of killed vaccine against the infection. | venereal infection with equine arteritis virus (eav) was established in each of seven mares by inoculation via the cervix with 20 ml of viral suspension (> or = 8 x 10(6) plaque-forming units; pfu), following treatment with prostaglandin and oestradiol. a dose of < or = 8 x 10(5) pfu produced infection in only five of eight mares. serum neutralizing antibody developed in mares manifesting clinical signs of equine viral arteritis (eva), and a weak antibody was detectable in one apparently healthy ... | 1997 | 9447481 |
| comparison of nucleic and amino acid sequences and phylogenetic analysis of open reading frames 3 and 4 of various equine arteritis virus isolates. | the genetic variation in equine arteritis virus (eav) protein-encoding open reading frames (orfs) 3 and 4 genes was investigated. nucleic and deduced amino acid sequences from seven different eav isolates (one european, one american and five canadian isolates) and the arvac vaccine strain were compared with those of bucyrus reference strain. orf 3 nucleotide and amino acid sequence identities between these isolates (including the arvac vaccine strain) and the bucyrus reference strain ranged from ... | 1997 | 9428144 |
| expression cloning and humoral immune response to the nucleocapsid and membrane proteins of equine arteritis virus. | to provide a convenient and sensitive method for the detection of equine arteritis virus (eav)-specific serum antibodies, we developed an immunoblot assay employing the eav nucleocapsid (n) and membrane (m) proteins expressed in a procaryotic expression vector (pmal-c2) for the production of recombinant maltose-binding (mbp) fusion proteins (mbp-n and mbp-m). the antigenic reactivity of the recombinant fusion proteins and their xa factor cleavage eav products was confirmed by immunoblot using ho ... | 1997 | 9384283 |
| alternative proteolytic processing of the arterivirus replicase orf1a polyprotein: evidence that nsp2 acts as a cofactor for the nsp4 serine protease. | the c-terminal half of the replicase orf1a polyprotein of the arterivirus equine arteritis virus is processed by a chymotrypsinlike serine protease (sp) (e. j. snijder et al., j. biol. chem. 271:4864-4871, 1996) located in nonstructural protein 4 (nsp4). three probable sp cleavage sites had previously been identified in the orf1a protein. their proteolysis explained the main processing products generated from the c-terminal part of the orf1a protein in infected cells (e. j. snijder et al., j. vi ... | 1997 | 9371590 |
| hemagglutination with equine arteritis virus. | equine arteritis virus (eav) grown on rk13 cell cultures was tested for hemagglutination (ha) with erythrocytes from a variety of species at 4 degrees c, room temperature and 37 degrees c. ha was observed at all temperatures with erythrocytes from mouse and chicken but not with those of cattle, horse, rabbit, guinea pig, mongolian gerbil, goose or chick embryo. chickens showed an individual variation in agglutinability of their erythrocytes, requiring selection of birds to obtain erythrocytes fo ... | 1997 | 9362047 |
| effect of the south african asinine-94 strain of equine arteritis virus (eav) in pregnant donkey mares and duration of maternal immunity in foals. | clinical, virological and serological responses were investigated in five pregnant donkey mares after experimental exposure to the south african asinine-94 strain of equine arteritis virus (eav), and the duration of maternal immunity to eav was studied in their foals. in four intranasally inoculated mares, fever with maximum rectal temperatures of 39.1-40.7 degrees c was recorded 2-11 d after challenge. all the inoculated mares developed mild depression, and a serous ocular and nasal discharge; ... | 1997 | 9352564 |
| effect of heparin on infection of cells by equine arteritis virus. | the number of plaques formed by equine arteritis virus (eav) and aujesky's disease virus (adv) was reduced to 14% and 5% of the untreated control (100%), respectively, by 10 u/ml of heparin, but could not be reduced below to 13 and 4%, respectively, by use of concentration up to 100 u/ml. an inhibitory effect of heparin, at concentration up to 100 u/ml, was not observed on parainfluenza virus 3 (piv-3). heparinase treatment of rk13 cells reduced the number of eav-, as well as adv-induced plaques ... | 1997 | 9300374 |
| experimental exposure of pregnant mares to the asinine-94 strain of equine arteritis virus. | clinical, virological and serological responses were evaluated in 10 pregnant mares after different challenge exposures to the asinine-94 strain of equine arteritis virus (eav). the outcome of maternal infection on the progeny was also investigated. mares were inoculated intranasally (n = 4), intramuscularly (n = 2), intravenously (n = 1), or contract-exposed (n = 3). all inoculated mares developed pyrexia, 5 showed mild clinical signs related to eav infection and 2 remained asymptomatic. viraem ... | 1997 | 9291073 |
| equine viral arteritis in newborn foals: clinical, pathological, serological, microbiological and immunohistochemical observations. | clinical, pathological, immunohistochemical, serological and microbiological findings are described for 2 geographically and temporally distinct equine arteritis virus (eav) epidemics in newborn foals. outbreak a occurred at a commercial standardbred breeding facility; outbreak b began in a group of research animals. clinical signs were severe and primarily referable to the respiratory tract. fever and leucopenia and/or thrombocytopenia were observed in foals surviving for more than 24 h. the mo ... | 1997 | 9234009 |
| detection of equine arteritis virus in the semen of carrier stallions by using a sensitive nested pcr assay. | a nested pcr, developed for the detection of equine arteritis virus (eav) in semen, detected less than 2.5 pfu of eav per ml of naturally infected seminal plasma. based on results from testing 88 semen samples from 70 stallions, the sensitivity and specificity of the test were 100 and 97%, respectively. | 1997 | 9230412 |
| molecular characterization of lelystad virus. | lelystad virus (lv), the prototype of porcine reproductive respiratory syndrome virus, is a small enveloped virus, containing a positive strand rna genome of 15 kb. lv is tentatively classified in the family arteriviridae, which consists of lactate dehydrogenase-elevating virus (ldv), equine arteritis virus (eav) and simian hemorrhagic fever virus (shfv). these viruses have a similar genome organization and replication strategy as coronaviruses, but the size of the genome is much smaller (12-15 ... | 1997 | 9220614 |
| failure to establish chronic infection of the reproductive tract of the male horse with a south african asinine strain of equine arteritis virus (eav). | eight sexually mature horse stallions were inoculated intranasally with a south african asinine strain of eav, a strain that was isolated from the semen of a donkey carrier. all horses developed fever, with maximum rectal temperatures of 38.9-39.9 degrees c recorded 3-6 d post challenge. six horses showed very mild clinical signs of equine viral arteritis and two were asymptomatic. the virus was recovered from the nasopharynxes of six horses 2-7 d after inoculation, and from buffy-coat samples o ... | 1997 | 9204499 |
| neutralization determinants of laboratory strains and field isolates of equine arteritis virus: identification of four neutralization sites in the amino-terminal ectodomain of the g(l) envelope glycoprotein. | the n-terminal hydrophilic ectodomain of the g(l) envelope glycoprotein of equine arteritis virus (eav) contains neutralization determinants of the virus. we developed a panel of 17 neutralizing murine monoclonal antibodies (mabs) to further characterize the neutralization determinants of eav. included were 6 mabs previously raised against a laboratory strain (eavucd) of the original bucyrus strain of eav, as well as 11 additional mabs that were raised against a neutralization-resistant variant ... | 1997 | 9185595 |
| is the south african asinine strain of equine arteritis virus a threat to local horses? | 1996 | 9120846 | |
| reverse transcriptase activity in chicken embryo fibroblast culture supernatants is associated with particles containing endogenous avian retrovirus eav-0 rna. | we have recently shown that live attenuated virus vaccines produced on chicken-derived cells contain low levels of particle-associated reverse transcriptase (rt). in both virus and corresponding control harvests produced on chicken embryo fibroblasts, these activities were present at significantly higher concentrations than in the vaccines. in order to identify the putative retrovirus sequence responsible for this activity, a novel method for the selective pcr amplification of particle-associate ... | 1997 | 9060660 |
| a survey for antibodies to equine arteritis virus in donkeys, mules and zebra using virus neutralisation (vn) and enzyme linked immunosorbent assay (elisa). | a seroepidemiological survey of donkeys in south africa (n = 4300) indicated a wide distribution and increasing prevalence of antibodies to equine arteritis virus (eav). donkey sera inhibited equine arteritis virus infection in virus neutralisation (vn) tests and in elisa specifically bound to a recombinant antigen derived from the bucyrus isolate of eav. these results suggest that donkeys have been exposed to the same serotype of this virus as circulates among horses. a good correlation existed ... | 1997 | 9031862 |
| a perspective on equine viral arteritis (infectious arteritis of horses). | 1996 | 9025155 | |
| an infectious arterivirus cdna clone: identification of a replicase point mutation that abolishes discontinuous mrna transcription. | equine arteritis virus (eav) is a positive-strand rna virus that uses a discontinuous transcription mechanism to generate a nested set of six subgenomic mrnas from which its structural genes are expressed. a stable bacterial plasmid (peav030) containing a full-length cdna copy of the 12.7-kb eav genome was constructed. after removal of a single point mutation in the replicase gene, rna transcripts generated in vitro from peav030 were shown to be infectious upon electroporation into bhk-21 cells. ... | 1997 | 9023370 |
| [equine arteritis virus: clinical symptoms and prevention]. | sero-epidemiological surveys have revealed that equine arteritis virus (eav) is prevalent in most european countries. the virus causes sporadic cases of respiratory disease and abortion in horses, the incidence of which has increased in recent years. mares and geldings eliminate virus after acute infection, but 30% to 60% of stallions become persistently infected. in these animals, eav is maintained within the reproductive tract and is shed continuously in the semen. persistent infection with ea ... | 1997 | 9012008 |
| genetic and amino acid analysis of the gl protein of canadian, american and european equine arteritis virus isolates. | the genetic variation in equine arteritis virus (eav) gl protein encoding gene was investigated. nucleic and deduced amino acid sequences from 7 different eav isolates, including 4 eastern canadian field isolates, were compared with those of the bucyrus reference strain. nucleotide sequence identities between these isolates and the bucyrus reference strain ranged from 87.5% (vienna isolate) to 93.9% (11958 isolate). amino acid identities with the bucyrus reference strain varied from 90.2% (vienn ... | 1997 | 9008807 |
| comparison of nucleic and amino acid sequences and phylogenetic analysis of the gs protein of various equine arteritis virus isolates. | the genetic variation in equine arteritis virus (eav) gs protein encoding gene was investigated. nucleic and deduced amino acid sequences from eight different eav isolates (one european, two american and five canadian isolates) were compared with those of the bucyrus reference strain. nucleotide and amino acid identities between these isolates and the bucyrus reference strain ranged from 92.3 to 96.4%, and 93.2 to 95.5%, respectively. however, phylogenetic tree analysis and estimation of genetic ... | 1996 | 8938984 |
| transmission of the south african asinine strain of equine arteritis virus (eav) among horses and between donkeys and horses. | lateral and sexual transmission of eav among horses and lateral transmission between donkeys and horses were attempted by experimental infection with the south african asinine strain. clinical, immunological and virological responses were evaluated. all intramuscularly inoculated horses developed very mild clinical signs, were viraemic, shed virus from nasopharynx, and seroconverted. lateral infection was demonstrated in one in-contact mare. reinfection of two stallions by intranasal instillatio ... | 1996 | 8917855 |
| equine arteritis virus: a review of clinical features and management aspects. | sero-epidemiological surveys have revealed that equine arteritis virus (eav) is prevalent in most european countries. the virus causes sporadic cases of respiratory disease and abortion in horses, the incidence of which has increased in recent years. mares and geldings eliminate virus after acute infection, but 30% to 60% of stallions become persistently infected. in these animals, eav is maintained within the reproductive tract and is shed continuously in the semen. persistent infection with ea ... | 1996 | 8903141 |
| sequence determination of the extreme 5' end of equine arteritis virus leader region. | the extreme 5' end of the leader sequence of four equine arteritis virus (eav) strains was obtained by using rapid amplification of cdna end method (5' race), and sequenced. seventeen more nucleotides were added upstream of the 5' end of the eav published genomic sequence. a common feature among the analyzed eav isolates was the presence of an aug start codon within the added sequence and the appearance of an intraleader open reading frame (orf) of 111 nucleotides which was predicted to encode a ... | 1996 | 8883367 |
| experimental pathological studies on mechanism of abortion caused by equine arteritis virus. | 1996 | 8870395 | |
| fatal experimental equine arteritis virus infection of a pregnant mare: immunohistochemical staining of viral antigens. | 1996 | 8844583 | |
| detection of related positive-strand rna virus genomes by reverse transcription/polymerase chain reaction using degenerate primers for common replicase sequences. | a set of degenerate sense and antisense primers were designed on the basis of short segments with identical amino acids in the predicted orf 1b replicase proteins of lactate dehydrogenase-elevating virus (ldv), equine arteritis virus (eav) and porcine reproductive and respiratory syndrome virus, strain lelystad virus (prrsv-lv), which are members of a new group of positive-strand rna viruses. reverse transcription/polymerase chain reaction amplification using this set of degenerate primers yield ... | 1995 | 8837898 |
| expression cloning and antigenic analysis of the nucleocapsid protein of equine arteritis virus. | a series of recombinant fusion proteins derived from equine arteritis virus (eav) open reading frame (orf) 7 have been used to define the immunoreactive region of the viral nucleocapsid (n) protein. reactivities of recombinant n fusion proteins with post-infection equine sera in immunoblots and elisas indicate that the major nucleocapsid protein epitope is located within amino acid residues 1-69. in elisas two recombinant nucleocapsid fusion proteins containing residues 1-69 (rn1-69) and 1-28 (r ... | 1995 | 8837890 |
| reactions to strangles vaccination. | 1995 | 8825322 | |
| genetic variation in open reading frame 2 of field isolates and laboratory strains of equine arteritis virus. | the open reading frame 2 (orf2) of three laboratory strains, the live attenuated vaccine virus, and 18 field isolates of equine arteritis virus (eav) from europe and north america was sequenced. the orf2 of eav encodes the gs protein that is abundantly expressed in infected cells but constitutes less than 2% of the virion protein mass. variation of orf2 among the isolates facilitated phylogenetic analysis that largely confirmed results of an earlier study based on sequence divergence of orf5 of ... | 1996 | 8806173 |
| processing of the equine arteritis virus replicase orf1b protein: identification of cleavage products containing the putative viral polymerase and helicase domains. | the replicase open reading frame lb (orf1b) protein of equine arteritis virus (eav) is expressed from the viral genome as an orf1ab fusion protein (345 kda) by ribosomal frameshifting. processing of the orf1b polyprotein was predicted to be mediated by the nsp4 serine protease, the main eav protease. several putative cleavage sites for this protease were detected in the orf1b polyprotein. on the basis of this tentative processing scheme, peptides were selected to raise rabbit antisera that were ... | 1996 | 8794297 |
| histopathological and immunofluorescent studies on transplacental infection in experimentally induced abortion by equine arteritis virus. | five pregnant mares, at between 6 and 8 months gestation, were experimentally infected with the bucyrus strain of equine arteritis virus (eav). of the five mares, four aborted and one died. the pathogenesis of the abortions was studied, using histopathologic techniques, tissue immunofluorescence and virus isolation. common microscopic lesions in the maternal reproductive organs indicated myometritis with a degeneration of the myocytes and an infiltration of the mononuclear cells. epithelial cell ... | 1996 | 8693844 |
| equine arteritis virus subgenomic mrna synthesis: analysis of leader-body junctions and replicative-form rnas. | in addition to the genomic rna, a 3' coterminal nested set of six subgenomic mrnas is produced in equine arteritis virus (eav)-infected cells. the seven viral rnas are also 5' coterminal, since they all contain a 206-nucleotide common leader sequence which is identical to the 5' end of the genome. a conserved penta-nucleotide sequence motif, 5' ucaac 3', was shown to be present at the junctions between the leader and body sequences in each of the mrnas. in addition, two alternative junction site ... | 1996 | 8676451 |
| intracellular synthesis, processing, and transport of proteins encoded by orfs 5 to 7 of porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome virus (prrsv), a small enveloped virus containing a positive-strand rna genome, possesses at least three major structural proteins designated n, m, and e. the n protein is considered as the major component of the nucleocapsid, whereas m and e are membrane-associated. previous studies using peptide-specific antibodies assigned these proteins to orfs 7, 6, and 5, respectively. in the present report, monospecific antisera raised against escherichia coli ... | 1996 | 8661418 |
| recognition of bronchopulmonary dysplasia in a newborn foal. | 1995 | 8654357 | |
| the arterivirus nsp4 protease is the prototype of a novel group of chymotrypsin-like enzymes, the 3c-like serine proteases. | the replicase of equine arteritis virus, an arterivirus, is processed by at least three viral proteases. comparative sequence analysis suggested that nonstructural protein 4 (nsp4) is a serine protease (sp) that shares properties with chymotrypsin-like enzymes belonging to two different groups. the sp was predicted to utilize the canonical his-asp-ser catalytic triad found in classical chymotrypsin-like proteases. on the other hand, its putative substrate-binding region contains thr and his resi ... | 1996 | 8617757 |
| equine viral arteritis. | 1995 | 8596181 | |
| equine viral arteritis with abortions: serological and virological evidence in germany. | an outbreak of clinical disease with abortions, suspected to be equine viral arteritis in germany was examined serologically and virologically. three of five animals tested seroconverted to eav, and eav was isolated from an aborted fetus. in view of the significant increase in seropositive horses, the need for control measures is emphasized. | 1995 | 8592914 |
| sexual and in-contact transmission of asinine strain of equine arteritis virus among donkeys. | two in a group of five naturally seropositive donkey stallions were found to shed equine arteritis virus (eav) in their semen as demonstrated by virus isolation. direct intramuscular inoculation of sonicated semen from one virus-shedding stallion (s3) caused clinical disease in two donkeys from which virus was recovered and in which seroconversion was detected. sexual transmission was confirmed in two mares mated to s3 when after a febrile response during which eav was isolated from huffy coats ... | 1995 | 8586720 |
| the phospholipid composition of enveloped viruses depends on the intracellular membrane through which they bud. | 1995 | 8566406 | |
| immunoperoxidase histochemistry as a diagnostic tool for detection of equine arteritis virus antigen in formalin fixed tissues. | 1996 | 8565959 | |
| phylogenetic analysis of open reading frame 5 of field isolates of equine arteritis virus and identification of conserved and nonconserved regions in the gl envelope glycoprotein. | the variation and phylogenetic relationship of open reading frame 5 (orf5) of 3 different laboratory strains of the original prototype bucyrus strain of equine arteritis virus (eav), the modified live virus vaccine (arvac, fort dodge laboratories), and 18 field isolates of eav from north america and europe were determined by comparison of their gene sequences. the viruses differed from the published sequence by between 3 (99.6% homology) and 94 (87.8%) nucleotides and by between 3 (98.8%) and 24 ... | 1995 | 8553578 |
| clinical features of the 1992 outbreak of equine viral arteritis in spain. | during 1992, a widespread outbreak of equine viral arteritis (eva) occurred at a riding establishment near barcelona, spain. a total of 31 out of 186 horses on the premises displayed clinical signs, most frequently, fever, depression, mild ventral and limb oedema and a vesicular-erosive stomatitis, with hypersalivation, petechiations and small ulcerations. affected horses developed illness of varying severity with only a few exhibiting a severe form of the disease and no mortality was recorded. ... | 1995 | 8536667 |
| lelystad virus, the causative agent of porcine epidemic abortion and respiratory syndrome (pears), is related to ldv and eav. | the genome of lelystad virus (lv), the causative agent of porcine epidemic abortion and respiratory syndrome (previously known as mystery swine disease), was shown to be a polyadenylated rna molecule. the nucleotide sequence of the lv genome was determined from a set of overlapping cdna clones. a consecutive sequence of 15,088 nucleotides was obtained. eight open reading frames (orfs) that might encode virus-specific proteins were identified. orf1a and orf1b are predicted to encode the viral rna ... | 1993 | 8517032 |
| molecular characterization of porcine reproductive and respiratory syndrome virus, a member of the arterivirus group. | porcine reproductive and respiratory syndrome virus (prrsv)-specific cdna clones spanning the 3' terminal 5 kb of the genomic rna were isolated, sequenced, and used as probes for identification of prrsv-specific rnas. the prrsv genome is a positive-stranded polyadenylated rna of about 15 kb. in infected cells, a 3' coterminal nested set of six major subgenomic mrnas could be demonstrated. within the 3' terminal 3.5 kb of the prrsv genome, six overlapping reading frames (orfs) were identified, ea ... | 1993 | 8438574 |
| relationship between onset of puberty and establishment of persistent infection with equine arteritis virus in the experimentally infected colt. | the relationship between stage of reproductive tract maturity and susceptibility to the experimental establishment of persistent infection with equine arteritis virus (eav) was investigated in 21 prepubertal and 15 peripubertal colts. five of six prepubertal colts inoculated intranasally remained infected in the reproductive tract from post-challenge day 28 to 93 and two of six from post-challenge day 120 to 180. no virus was detected in five of these animals killed on post-challenge day 210. ea ... | 1993 | 8408779 |
| equine viral arteritis. | equine viral arteritis is an infrequently encountered contagious viral disease of equids that has assumed increased veterinary medical and economic significance since the 1984 epidemic in thoroughbreds in kentucky. the most important consequences of this infection are abortion in the mare and establishment of the carrier state in the stallion. equine arteritis virus becomes localized in the reproductive tract of a relatively high percentage of infected stallions which serve as very efficient tra ... | 1993 | 8395325 |
| equine viral arteritis in britain. | 1993 | 8393227 | |
| equine viral arteritis. | 1993 | 8393224 | |
| serological evidence of equine arteritis virus in donkeys in south africa. | this paper reports the first serological evidence of exposure of donkeys to equine arteritis virus. seven hundred and thirty-four serum samples collected between 1989 and 1992 from donkeys in different areas of south africa were examined for the presence of antibodies against this virus by a microneutralization test. seventeen percent of serum samples tested positive. the distribution of seropositive animals varied from none in the western cape province and the transvaal highveld to 30% in the n ... | 1993 | 8392682 |
| complete genomic sequence and phylogenetic analysis of the lactate dehydrogenase-elevating virus (ldv). | the apparently complete sequence of the rna genome of the neurovirulent isolate of lactate dehydrogenase-elevating virus (ldv-c) has been determined. the ldv-c genome is at least 14,222 nucleotides in length and contains eight open reading frames (orfs). orf 1a, which encodes a protein of 242.8 kda and is located at the 5' end of the genome, contains at least two putative papain-like cysteine protease domains, and one putative chymotrypsin-like serine protease domain. this orf terminates with a ... | 1993 | 8389075 |
| equine arteritis virus in an imported stallion. | 1993 | 8387715 | |
| sequences of 3' end of genome and of 5' end of open reading frame 1a of lactate dehydrogenase-elevating virus and common junction motifs between 5' leader and bodies of seven subgenomic mrnas. | the sequences of the 3'-terminal 3.7 kb of the genome and of a 1.7 kb 5' end cdna clone of one isolate of lactate dehydrogenase-elevating virus (ldv) are reported. the 3' end sequence encodes six major independent open reading frames (orfs 2 to 7), which are overlapping by between one and 130 nucleotides. each orf is expressed at the 5' end of one of six 3'-coterminal subgenomic mrnas (mrnas 2 to 7, respectively; 3.5 to 0.8 kb). the smallest mrna, mrna 7, encodes the nucleocapsid protein, vp1; m ... | 1993 | 8385693 |
| research note: avian leukosis retroviral genes are not detected in geese. | genomic dna from four strains of geese was analyzed for the presence of endogenous viral elements using a probe that can detect over 20 rous-associated endogenous viral genes (ev genes) in chickens, as well as a probe and protocol that detects endogenous avian viruses (eav). southern blot analysis of genomic dna did not reveal any ev genes in dna of 15 geese from chinese, synthetic, or two embden goose strains. even under low stringency conditions, using a probe that covered most of the polymera ... | 1993 | 8382817 |
| the horserace betting levy board's code of practice for equine viral arteritis for the 1994 breeding season. | the horserace betting levy board formulates codes of practice for the control of contagious equine metritis and other equine bacterial venereal diseases, and equine viral arteritis and equid herpesvirus 1. this year's codes have just been published and the code of practice for eva, reproduced below, has been substantially amended following the recent outbreak in the uk. the code is intended for use by veterinary surgeons and breeders of thoroughbred and non-thoroughbred horses. the hblb states t ... | 1993 | 8310626 |
| pathological changes associated with equine arteritis virus infection of the reproductive tract in prepubertal and peripubertal colts. | the nature and extent of changes associated with equine arteritis virus (eav) infection of the reproductive tract was documented in 21 prepubertal and 15 peripubertal colts. this study was part of an investigation into the relationship between stage of reproductive tract maturity and susceptibility to the experimental establishment of persistent infection with eav. after intranasal challenge with a field isolate of eav, all colts developed clinical signs of equine viral arteritis (eva) from whic ... | 1993 | 8300916 |
| [an outbreak of equine arteritis virus infection in a riding school]. | a major part of the residing horses and ponies of a riding school in noord-holland became affected by a febrile disorder that included anorexia, depression, conjunctivitis, urticaria, edema of the legs and laborious locomotion. all remaining horses fell ill within one week. based on the clinical symptoms the disorder was diagnosed as vasculitis. with serology the causative agent of the disorder appeared to be equine arteritis virus. | 1994 | 8296297 |
| complement-dependent serum neutralization with virulent and avirulent bucyrus strains of equine arteritis virus. | virulent and avirulent strains of bucyrus equine arteritis virus (eav) were used to raise antiserum in horses. serum neutralization (sn) tests were performed with and without the addition of guinea pig complement. the inclusion of ten percent guinea pig serum in the virus suspension was sufficient for optimal enhancement of sn titres at any immune stages after immunization. immune serum prepared against avirulent virus reacted only with homologous virus and there was no complement enhancement. i ... | 1993 | 8273282 |
| association of microbiologic flora with clinical, endoscopic, and pulmonary cytologic findings in foals with distal respiratory tract infection. | undifferentiated distal respiratory tract disease (nasal discharge, cough, pneumonia) in foals (1 to 8 months old) is a burdensome economic problem on breeding farms; yet, the infective agents associated with these episodes have not been well described. possible causes of these episodes of illness were investigated by culturing specimens of proximal and distal airways of clinically diseased foals (n = 101), prior to any treatment, for aerobic and anaerobic bacteria and viruses (rhinoviruses, equ ... | 1993 | 8250386 |
| horserace betting levy board recommendation for the 1993 covering season. common code of practice for equine viral arteritis. | 1993 | 8221035 | |
| equine viral arteritis--a challenge for the british horse industry. | 1993 | 8221034 | |
| molecular characterization of positive-strand rna viruses: pestiviruses and the porcine reproductive and respiratory syndrome virus (prrsv). | molecular characterization has become an important tool for the analysis of viruses including their classification. the manuscript focuses on the molecular analysis of two members of the genus pestivirus (hog cholera virus, hcv and bovine viral diarrhea virus, bvdv) and of the recently discovered porcine reproductive and respiratory syndrome virus (prrsv). the first protein encoded within the single large pestivirus orf is a nonstructural protein with autoproteolytic activity. the cleavage site ... | 1993 | 8219812 |
| eva vaccine granted animal test certificate. | 1993 | 8212469 | |
| equine arteritis virus contains a unique set of four structural proteins. | 1993 | 8209738 | |
| the coronaviruslike superfamily. | 1993 | 8209737 | |
| proteolytic processing of the n-terminal region of the equine arteritis virus replicase. | a papainlike cysteine protease (pcp) domain in the n-terminal region of the equine arteritis virus (eav) replicase was identified by in vitro translation and mutagenesis studies. the eav protease was found to direct an autoproteolytic cleavage at its c-terminus which leads to the production of an approximately 30k n-terminal replicase product (nsp1) containing the pcp domain. amino acid residues cys164 and his230 of the eav replicase polyprotein were identified as the most likely candidates for ... | 1993 | 8209735 |
| comparison of m and n gene sequences distinguishes variation amongst equine arteritis virus isolates. | cdna copies of the m and n genes of equine arteritis virus (eav) isolates were synthesized by reverse transcription followed by polymerase chain reaction amplification. the cdna was subjected to a cycle sequencing strategy using taq polymerase, and the nucleotide and derived amino acid sequences of 10 virus isolates were compared. the m and n genes of all isolates had the same initiation and termination sites as the prototype bucyrus strain and the encoded proteins were conserved between viruses ... | 1994 | 8207415 |
| detection of equine arteritis virus following amplification of structural and nonstructural viral genes by reverse transcription-pcr. | a reverse transcription (rt)-pcr assay was developed for the detection of equine arteritis virus (eav) in cell culture supernatant and in horse semen. four different sets of oligonucleotide primers complementary to sequences located in the 3' end of the polymerase gene (open reading frame [orf] 1b) and to sequences representing the entire orfs 3, 4, and 7, which encode for nonstructural (orfs 3 and 4) or viral nucleocapsid (orf 7) proteins, were compared for their abilities to amplify the target ... | 1994 | 8195375 |
| export of stallions vaccinated against equine viral arteritis. | 1994 | 8128564 | |
| identification of major differences in the nucleocapsid protein genes of a québec strain and european strains of porcine reproductive and respiratory syndrome virus. | the sequence of the 3'-terminal region of the genome of québec reference strain iaf-exp91 of porcine reproductive and respiratory syndrome virus (prrsv) was investigated by analysis of four cdna clones. the 3'-terminal 530 nucleotides (nt) encompassed a large open reading frame with a coding capacity of 123 amino acids (m(r) 13,649). the predicted protein was extremely basic and hence was considered to correspond to the nucleocapsid (n) protein gene. when compared to the homologous sequences of ... | 1994 | 8126467 |
| validation of virus inactivation and removal for the manufacturing procedure of two immunoglobulins and a 5% serum protein solution treated with beta-propiolactone. | intravenous immunoglobulins and serum protein solutions are manufactured from human plasma pools of healthy, screened donors. a step-by-step validation of virus removal and/or inactivation was performed for the manufacturing process, which includes cold ethanol fractionation, beta-propiolactone (beta-pl) treatment, uv irradiation, thermal inactivation and other chemical and physical purification steps. the total viral clearance factors achieved for the entire manufacturing process were by severa ... | 1993 | 8117439 |
| monoclonal antibodies to equine arteritis virus proteins identify the gl protein as a target for virus neutralization. | monoclonal antibodies (mabs) to equine arteritis virus (eav) proteins were produced and characterized. the protein specificities of eight mabs were determined definitively by immunoprecipitation of eav proteins expressed from vaccinia virus recombinants (vvrs). included were two new vvrs produced for this study, expressing the m and the gl proteins, respectively. three mabs were determined to be n-specific and five mabs recognized the gl protein. one gl-specific mab, 17f5, of the iga class, effi ... | 1994 | 8077945 |
| proteolytic processing of the replicase orf1a protein of equine arteritis virus. | to study the proteolytic processing of the equine arteritis virus (eav) replicase open reading frame 1a (orf1a) protein, specific antisera were raised in rabbits, with six synthetic peptides and a bacterial fusion protein as antigens. the processing of the eav orf1a product in infected cells was analyzed with western blot (immunoblot) and immunoprecipitation techniques. additional information was obtained from transient expression of orf1a cdna constructs. the 187-kda orf1a protein was found to ... | 1994 | 8057457 |
| lelystad virus belongs to a new virus family, comprising lactate dehydrogenase-elevating virus, equine arteritis virus, and simian hemorrhagic fever virus. | lelystad virus (lv) is an enveloped positive-stranded rna virus, which causes abortions and respiratory disease in pigs. the complete nucleotide sequence of the genome of lv has been determined. this sequence is 15.1 kb in length and contains a poly(a) tail at the 3' end. open reading frames that might encode the viral replicases (orfs 1a and 1b), membrane-associated proteins (orfs 2 to 6) and the nucleocapsid protein (orf7) have been identified. sequence comparisons have indicated that lv is di ... | 1994 | 8032274 |
| enzymatic amplification of lactate dehydrogenase-elevating virus. | to improve the detection of lactate dehydrogenase-elevating virus (ldv), we developed a pcr assay. primers were selected from orf7, encoding nucleocapsid protein vp1. no specific amplification was observed with any other common murine virus or with rnas from the closely related lelystad virus and equine arteritis virus. in experimentally infected mice, ldv could be detected in plasma in both the acute and the persistent phases. ldv was also detected by the pcr in contaminated pools of plasmodium ... | 1994 | 7989557 |