PMID(sorted descending)
transport of viruses through fetal membranes: an in vitro model of perinatal transmission.a model system for perinatal transmission of viral infections was developed and transport of infectious virus particles through fetal membranes was investigated. viruses of different families known to cause serious intrauterine infections were selected, including relevant and model viruses: the dna-viruses hsv-1 and -2 as well as the animal herpes viruses bhv-1 and shv-1, the rna-virus bvdv as a model for hepatitis c virus, hiv-1 and -2, and ppv as a model for parvovirus b19. migration of infect ...19989557298
production of strain specific antibodies against a synthetic polypeptide corresponding to the n-terminal region of the plum pox potyvirus coat protein.comparison of the predicted coat protein amino acid sequence of the 'sweet cherry' strain of plum pox potyvirus (ppv-swc) with the corresponding regions of several other ppv strains indicated that the main differences are in the n-terminal region. polyclonal antibodies were produced against a synthetic peptide corresponding to the 1-14 sequence of the n-terminal region of ppv-swc coat protein. they specifically detected ppv-swc in different immunochemical tests.19979504763
plum pox potyvirus resistance associated to transgene silencing that can be stabilized after different number of plant generations.nicotiana benthamiana plants were transformed with a fragment of the plum pox potyvirus (ppv) genome that encodes the nuclear inclusion a (nia) and b (nib) proteins and the n-terminus of the capsid protein (nia-nib-cp). lines transformed with this ppv genomic fragment harboring mutations in the gdd replicase-motif were also obtained. plants of niadeltav lines that carry a gdd to vdd mutation in the ppv transgene, were immune to ppv infection. the resistance was highly specific, since it was only ...19989469941
simultaneous detection and typing of plum pox potyvirus (ppv) isolates by heminested-pcr and pcr-elisa.two techniques for simultaneous detection and typing of plum pox potyvirus (ppv) isolates belonging to the d or m serotypes, heminested pcr (h-pcr) and pcr-elisa, have been developed. ten ppv isolates typed using ppv-d and ppv-m specific monoclonal antibodies by elisa-dasi were used to validate these two methods. the results obtained show a complete coincidence of the nucleic acid-based techniques with the serological data. when serial dilutions of infected plant extracts were assayed, h-pcr and ...19979389402
the motif v of plum pox potyvirus ci rna helicase is involved in ntp hydrolysis and is essential for virus rna replication.the plum pox potyvirus (ppv) protein ci is an rna helicase whose function in the viral life cycle is still unknown. the ci protein contains seven conserved sequence motifs typical of rna helicases of the superfamily sf2. we have introduced several individual point mutations into the region coding for motif v of the ppv ci protein and expressed these proteins in escherichia coli as maltose binding protein fusions. mutations that abolished rna helicase activity also disturbed ntp hydrolysis. no mu ...19979358154
non-suppurative myocarditis in piglets associated with porcine parvovirus infection.the involvement of porcine parvovirus (ppv) in the aetiology of non-suppurative myocarditis in sucking piglets was investigated by a polymerase chain reaction (pcr), designed to assess the presence of viral genome in formalin-fixed paraffin wax-embedded tissue of diseased animals. myocardium and lung of stillborn piglets with a confirmed ppv infection were used to set up the pcr amplification method. subsequently, 20 myocardia with inflammatory lesions were examined in parallel with 20 myocardia ...19979352435
validation of the heat treatment step used in the production of diaspirin crosslinked hemoglobin (dclhb) for viral inactivation--effect of crosslinking.two experiments were performed to assess viral inactivation during the crosslinking and heat treatment steps of the dclhb manufacturing process. stroma free hemoglobin (sfhb) collected from a large scale manufacturing lot was tested in a 1:680 scaled down system in which the key parameters used in the manufacturing process were replicated. in the first study porcine parvovirus (ppv), a non-enveloped virus, was used to assess inactivation, while in the second study bovine viral diarrhea virus (bv ...19979352057
a congenital persistent infection of bovine virus diarrhoea virus in pigs: clinical, virological and immunological observations.we report on a lifelong 'carrier' state of non-cytopathic bovine virus diarrhoea virus (bvdv) in an otherwise healthy pig. three out of 13 pigs of a litter congenitally infected with bvdv survived for more than 3 months. one pig was bvdv seropositive at 1 month, the second seroconverted between 6 and 8 months, and the third remained viraemic and bvdv-immunotolerant until slaughter at 26 months. the latter pig, a boar, excreted virus in oropharyngeal fluid, urine and semen. ejaculates, however, d ...19979323848
comparison of two different methods for inactivation of viruses in order to compare protocols for inactivation of viruses potentially present in biological specimens, three different model viruses were treated in bovine serum by two different inactivation methods: samples were subjected either to chemical inactivation with ethylenimine (el) at concentrations of 5 and 10 mm at 37 degrees c for periods up to 72 h or to electron-beam irradiation in frozen and liquid form with doses varying between 11 and 46 kgy. the chemical inactivation resulted in nonlinear t ...19979302195
specific detection of d- and m-isolates of plum pox virus by immunoenzymatic determination of pcr products.molecular techniques based on the polymerase chain reaction (pcr) can provide rapid and sensitive diagnosis of plum pox virus (ppv), the causal agent of the devastating 'sharka' disease of stone fruit trees. the present study compared routine polymerase chain reaction (pcr) procedures against a new system, pcr-elisa (boehringer mannheim), which enables immunoenzymatic detection of pcr products. the results show that this hybridisation system ensures fast and more sensitive detection of ppv assoc ...19979300377
recombinant parvovirus-like particles as an antigen carrier: a novel nonreplicative exogenous antigen to elicit protective antiviral cytotoxic t develop a strategy that promotes efficient antiviral immunity, hybrid virus-like particles (vlp) were prepared by self-assembly of the modified porcine parvovirus vp2 capsid protein carrying a cd8(+) t cell epitope from the lymphocytic choriomeningitis virus nucleoprotein. immunization of mice with these hybrid pseudoparticles, without adjuvant, induced strong cytotoxic t lymphocyte (ctl) responses against both peptide-coated- or virus-infected-target cells. this cd8(+) class i-restricted cyt ...19979207121
long sequences in the 5' noncoding region of plum pox virus are not necessary for viral infectivity but contribute to viral competitiveness and pathogenesis.the 5'-terminal 31 nucleotides of the 146-nucleotides-long 5' noncoding region of plum pox potyvirus (ppv) are highly conserved in all the members of the potyvirus genus. to map the sequences of the 5' noncoding region that are necessary in vivo for infectivity, we have constructed a nested set of substitution and deletion mutants. while we were not able to infect nicotiana clevelandii plants with full-length ppv transcripts bearing mutations in the 5'-terminal 35 nucleotides of the viral genome ...19979201225
identification of three distinct antigenic sites in parapoxviruses.monoclonal antibodies (mabs) were generated in balb/c mice immunized with gradient-purified particles, envelopes and cores of intracellular mature orf virus d-1701. three distinct antigenic sites were identified in this virus strain. their topographical relationships was determined by pairwise epitope specificity studies in competition elisas. one mab (class igm) neutralized virus infectivity. four micrograms/ml purified igm gave a 50% reduction of 100 pfu of orf virus d-1701. as shown by immuno ...19979170506
nonaldehyde sterilization of biologic tissue for use in implantable medical devices.biologic tissue stabilized by dye-mediated photooxidation has found application in implantable devices. the desire to avoid aldehydes in the processing of photooxidized tissues led to the development of a nonaldehyde, iodine based sterilant. the interaction of tissue with iodine was indicated by a change in tissue shrinkage temperature, dependent upon solution and incubation parameters. the amino acid tyrosine also was altered, presumably because of aromatic ring iodination. transmission electro ...19979116349
virucidal treatment of blood protein products with uvc radiation.the virus safety of blood derivatives continues to be of concern, especially with respect to nonenveloped and/or heat-stable viruses. previously, we demonstrated that treatment of whole plasma, ahf concentrate or fibrinogen with short wavelength ultraviolet light (uvc) results in the inactivation of > or = 10(6) infectious doses (id) of encephalomyocarditis virus (emcv), hepatitis a virus (hav) and porcine parvovirus (ppv), each of which is nonenveloped. protein recovery was enhanced greatly by ...19979077126
detection of antibodies against porcine parvovirus nonstructural protein ns1 may distinguish between vaccinated and infected pigs.the humoral antibody response against the nonstructural protein ns1 and the structural protein vp2 of porcine parvovirus (ppv) was evaluated by immuno-peroxidase test (ipt) and enzyme linked immuno sorbent assay (elisa) using recombinant ppv antigens. the coding sequence for ns1 and vp2 was inserted into the baculovirus. autographa californica nuclear polyhedrosis virus (acnpv) genome resulting in two recombinant baculoviruses acnpv-ns1 and acnpv-vp2, respectively. sf9 cells (spodoptora frugidip ...19979050166
processing of the plum pox virus polyprotein at the p3-6k1 junction is not required for virus viability.proteolytic processing of the potyvirus polyprotein is mainly performed by the virus-encoded nia protease, whose cleavage sites are characterized by conserved heptapeptide sequences. partial processing at the cleavage site present between the p3 and 6k1 cistrons by the plum pox potyvirus (ppv) nia protease has been previously shown to occur in vitro. we have now studied the role of polyprotein processing at the p3-6k1 junction in vivo, using a full-length ppv cdna clone. ppv mutant transcripts c ...19959049341
acute outbreak of porcine parvovirus infection in mozambique.investigations were made to determine the causal agent of an acute outbreak of abortions recorded in a swine herd in mozambique. isolation of porcine parvovirus and demonstration of its specific antibodies accomplished by using enzyme-linked immunosorbent assay, haemagglutination inhibition and immunofluorescent tests, indicated that porcine parvovirus was the causal agent of the abortions. other pathogenic agents causing reproductive failure, e.g. pseudorabies virus, leptospira or brucella spec ...19958966762
first findings of plum pox virus in walnut trees (juglans regia l.)plum pox virus (ppv) was transmitted from infected buds and leaves of walnut tree (juglans regia l.) on the following herbaceous indicators: chenopodium foetidum schrad., nicotiana bigelovii var. quadrivalvis fuchs., n. clevelandii x n. glutinosa. a positive elisa reaction with antisera against ppv was obtained from infected buds and leaves of juglans regia l. and from attacked leaves of indicator plants.19968886101
comparison of the safety and immunogenicity of a pneumococcal conjugate with a licensed polysaccharide vaccine in human immunodeficiency virus and non-human immunodeficiency virus-infected compare the safety and immunogenicity of a 5-valent pneumococcal conjugate vaccine to a licensed 23-valent polysaccharide pneumococcal vaccine in hiv-infected and non-hiv-infected children > or = 2 years old.19968852905
age-specific prevalence of porcine parvovirus antibody in feral pigs from a site in the northern territory. 19958787527
diagnosis of fetal infection with porcine parvovirus by in situ situ hybridization (ish) for the diagnosis of fetal infection with porcine parvovirus (ppv) was compared with immune electron microscopy (iem) and serology by immunofluorescence (if) for its sensitivity and its applicability in a routine diagnostic laboratory. the technique was applied to the examination of sections of formalin-fixed paraffin-embedded tissues from 68 fetuses. fifty-three of these fetuses were diagnosed serologically since they had a crown rump length of more than 17 cm, i.e. ...19958748552
the rna helicase ci from plum pox potyvirus has two regions involved in binding to rna.the plum pox virus (ppv) protein ci is an rna helicase, whose function in the virus replication is still unknown. recently, an rna binding domain was mapped to a region of the ci protein that includes the arginine-rich motif vi typical of rna helicases of the superfamily sf2. in the present study, a second region involved in rna binding activity of the ci protein has been identified. northwestern assays with a series of maltose-binding protein fusions that contain different ci fragments showed t ...19968690088
inactivation of virus during anaerobic digestion of manure in laboratory scale biogas reactors.reduction of porcine parvovirus, bovine enterovirus and faecal enterococci were measured in biogas reactors continuously run on manure and manure supplemented with household waste at 35 degrees c and 55 degrees c and in batch test run at 70 degrees c. the aim of the experiments was to study the sanitation effect of anaerobic digestion and to evaluate the use of faecal enterococci as an indicator of sanitation. parallel studies on the reduction of virus and faecal enterococci were done in physiol ...19968678476
print-capture pcr: a simple and highly sensitive method for the detection of plum pox virus (ppv) in plant tissues. 19968668554
genome organization of the kresse strain of porcine parvovirus: identification of the allotropic determinant and comparison with those of nadl-2 and field isolates.the kresse strain of porcine parvovirus (ppv) was cloned into puc19, and independent infectious clones were sequenced. the ppv kresse and nadl-2 strains, which have different pathogenicities, shared an identical genomic organization and a high degree of sequence identity. partial genomes (1.5 or 1.6 kb) of 15 field isolates were also amplified by pcr in regions with significant sequence differences between the laboratory strains. five amino acid differences were consistently present within the v ...19968642680
the use of respiratory-tract cultures in the diagnosis of invasive pulmonary define the role of lower-respiratory-tract cultures in the diagnosis of invasive pulmonary aspergillosis (ipa) in immunocompromised hosts.19968629651
financial evaluation of vaccination and testing alternatives for control of parvovirus-induced reproductive failure in identify the preferable testing and vaccination strategy for control of porcine parvovirus (ppv) during a 6-month period.19968617643
detection of respiratory syncytial virus by reverse transcription-pcr and hybridization with a dna enzyme immunoassay.nasal aspirates from 238 infants hospitalized with acute respiratory infections during the winter of 1994 and 1995 were tested for respiratory syncytial virus (rsv) by immunofluorescence assay (ifa) and the viral isolation technique (vit) and by two pcr and hybridization methods: reverse transcription pcr 1 (rt-pcr1), which amplifies the rnas of all rsv strains, and rt-pcr-2, which allows subgroup classification of rsv. rt-pcr-1 and rt-pcr-2 detected viral sequences in 56.7% (135 of 238) and 48. ...19958586738
localization of fruit tree viruses by immuno-tissue printing in infected shoots of malus sp. and prunus sp.immuno-tissue printing protocols for the localization of apple chlorotic leaf spot virus (aclsv), stem grooving virus (sgv) and plum pox virus (ppv) in shoots of prunus and malus in vitro have been established for routine diagnosis in a virus elimination program. since these viruses belong to different virus genera, the protocols were adapted according to the properties of the virus under investigation. accumulation of aclsv was highest in the base of the stem and decreased towards the apex of t ...19958537455
immunodetection of the plum pox virus helper component in infected plants and expression of its gene in transgenic plants.tobacco plants (nicotiana tabacum cv. xanthi) have been transformed via agrobacterium tumefaciens vectors, with cdnas corresponding to the plum pox virus (ppv) cistron 2 encoding helper component (hc-pro) and with the first two and half cistrons of the ppv genome. presence of the hc-pro in ppv-infected plants and transgenic plants transformed with the gene coding for this protein was investigated using specific polyclonal antibodies produced against the ppv hc-pro. the results suggest that two p ...19938517789
[suppression of replication of swine parvoviral antisense rna against the ns ppv gene in swine thyroid gland cells].the possibility of suppression of porcine parvovirus (ppv) reproduction in the culture of thyroid gland cells of a swine that contain the integrated genes for asrna against the nonstructural proteins of the virus has been studied. 10 cell lines with the asrna genes have been obtained. the line with the maximal number of integrated gene copies was used to inflict with the parvovirus. the expression of asrna in this cell line was shown to lead to 95% suppression of ppv replication as compared with ...19938510680
evaluation of testing algorithms following the use of combination hiv-1/hiv-2 eia for screening purposes.the licensure of combination human immunodeficiency virus type 1 and type 2 (hiv-1/hiv-2) enzyme immunoassays (eias) by the food and drug administration has been accompanied by a recommendation that u.s. blood banks begin testing the nation's blood supply for hiv-2 by june 1, 1992. the performance of a recently licensed combination hiv-1/hiv-2 eia (genetic systems) was evaluated using 3100 sera collected in the united states. a total of 2,049 sera were obtained from populations with low risk for ...19938457381
3'-terminal sequence of the plum pox virus ps and ŏ6 isolates: evidence for rna recombination within the potyvirus group.the sequence of the 3'-terminal 1768 nucleotides of the ps and ŏ6 isolates of plum pox virus (ppv) has been determined and compared with that of the equivalent regions of other ppv isolates sequenced previously. the sequenced region is part of the ppv open reading frame encoding the last 186 amino acids of the nib protein and the coat protein (cp, 330 amino acids), followed by a non-coding region of 220 nucleotides and a poly(a) tail. ppv-ps and ppv(-)ŏ6, just like ppv-el amar, show rather high ...19938445362
role of the tk+ phenotype in the stability of pigeonpox virus recombinant.insertion of foreign dna containing the e. coli gpt marker by homologous recombination in the pigeonpox virus (ppv) thymidine kinase (tk) gene and selection for the presence of this dna in the viral genome produced unstable recombinants after 3 plaque purifications. we highlight the persistence of duplicated tk dna sequences arising from single crossing over, due to the growth advantage of tk+ virus. restoration of the tk function by coinsertion of the vaccinia virus tk gene led to stable tk+ re ...19938394070
an economic assessment of porcine parvovirus vaccination.a decision analysis model was designed to evaluate the cost effectiveness of a vaccination program for preventing endemic or epidemic porcine parvovirus (ppv) induced reproductive failure in a 100-sow pig herd. the results showed that the cost of vaccination was less than the cost incurred by continuing endemic ppv infection, or the cost of a severe epidemic. a long term vaccination program is a cost effective method for controlling ppv-induced reproductive failure in pig herds suffering endemic ...19938393655
tissue tropisms of porcine parvovirus in swine.late-term gestation swine fetuses, similar to adult animals, are able to effectively mount immune response and survive porcine parvovirus (ppv) infection. an exception to this is the kresse strain of ppv, which causes fetal death in late-term gestation swine fetuses. in an effort to understand the basis for this profound difference in pathogenicity between kresse strain and the prototype strain of ppv, nadl-8, studies were designed to examine potential difference in sites of replication and quan ...19938390826
a new method for rapidly removing contaminating micro-organisms from porcine parvovirus or pseudorabies virus master-seed suspensions.virus-contaminated cell cultures are a major problem in the bio-industry. methods employed to date to remove contaminating micro-organisms are slow and costly, and a new method is proposed here which is simple and rapid. the method uses polyacrylamide beads coated with specific antibodies which yielded bead-antibody-virus complexes when suspended in the virus solution to be cleared. the purified virus was propagated in cells which show phagocytic activity. vaccine master-seed virus is shown to b ...19938383386
monoclonal antibodies suitable for plum pox virus determination.monoclonal antibodies (mabs) to plum pox virus (ppv) were obtained after immunization of balb/c mice with purified ppv-w isolate. spleen cells from a mouse showing a high serum titer were used for fusion with sp2/0-ag14 myeloma cells. culture supernatants were screened for specific antibody production against ppv-w isolate using indirect elisa. a total of six stable hybridoma lines producing mabs of igg class were obtained. all four ppv isolates tested (w, a, d and m) can be distinguished by the ...19938314598
genomic organization and mapping of transcription and translation products of the nadl-2 strain of porcine parvovirus.the nadl-2 strain of ppv was cloned into puc19 and independent infectious clones were sequenced. this permitted a correction of published sequences and to predict a cruciform structure as an alternative to the 5'-hairpin of the "-" strand. this 5'-end structural covariance is shared with other parvoviruses of the same group and two alternative sequences ("flip" and "flop") were present in the region of the cruciform. transcript and translation product mapping allowed the prediction of the locati ...19938212598
use of polymerase chain reaction to detect porcine parvovirus associated with swine embryos.the role of porcine parvovirus (ppv) in inducing reproductive failure in swine has been extensively documented. however, information is not available as to the risk of ppv transmission by embryo transfer. using the polymerase chain reaction (pcr) technique, ppv-specific dna was detected in association with 4-day-old porcine embryos incubated in vitro in the presence of nadl-8 strain of ppv, despite attempts to rid the embryos of virus by either washing or treatment with pronase or trypsin. the p ...19948192255
a serologic survey of selected viral and bacterial diseases of european wild hogs, great smoky mountains national park, usa.blood samples were collected from 108 wild hogs (sus scrofa) from the great smoky mountains national park (gsmnp), usa, february to july 1990. we found no antibodies for swine brucellosis, pseudorabies, bovine virus diarrhea virus or porcine rotavirus infection. antibody titers to porcine parvovirus were found in 15 (14%) samples and antibody to one or more leptospiral serovars was found in 48 (44%) samples. thirty-nine (89%) of the 44 positive samples reacted to all five leptospiral serovars te ...19948151810
[the infectious causes of abortion and stillbirth in swine in switzerland].fetuses and placentae of 171 cases of porcine abortion, stillbirth and mummification were examined for pathological lesions, bacterial infections and ppv (porcine parvovirus) infection. furthermore igg (immunoglobulin g) levels were determined in fetal body fluids. selected maternal sera were tested for antibodies against leptospira, aujeszky's disease and hog cholera. ppv infection was diagnosed in 29.2% of all cases. bacterial abortion was diagnosed in 8.2%. indications for an infectious agent ...19938128797
comparative sequence analysis of four complete primary structures of plum pox virus strains.the complete nucleotide sequence of plum pox virus (ppv) strain sk 68 was determined from a series of overlapping cdna clones. the exact 5' terminus was determined by direct rna sequencing. the rna sequence was 9786 nucleotides in length, excluding a 3' terminal poly(a) sequence. the large open reading frame starts at nucleotide position 147 and is terminated at position 9568. comparison of cistrons from other plum pox virus strains with those predicted for the sk 68 strain indicated the same ge ...19938122394
a novel non-mineral oil-based adjuvant. ii. efficacy of a synthetic sulfolipopolysaccharide in a squalane-in-water emulsion in pigs.the adjuvanticity of a sulfolipopolysaccharide (slp) incorporated into a squalane-in-water emulsion (slp/s/w) was compared with that of a mineral oil-in-water (o/w) adjuvant currently used in commercial porcine vaccines. groups of pigs were immunized twice with vaccines comprising either inactivated influenza virus (iflu3 containing strains a/swine, mrc-11 and x-79), inactivated pseudorabies virus (iprv), live pseudorabies virus (prv) or inactivated porcine parvovirus (ippv) as antigen and slp/s ...19948085386
return to oestrus after first insemination in sow herds (incidence, seasonality, and association with reproductivity and some blood parameters).as no systematic study has been done to get an accurate estimate of the incidence of return to oestrus after first insemination in sows in the netherlands, the objectives of this investigation were: 1) to obtain an estimate of the incidence of return to oestrus after insemination at the herd level; 2) to investigate the association between incidence of return to oestrus after first insemination and reproduction characteristics in order to get an impression of the economic importance of reproduct ...19947985351
porcine parvovirus associated with cutaneous lesions in piglets. 19947948207
nucleotide sequence of the coat protein gene of the skierniewice isolate of plum pox virus (ppv).the coat protein (cp) gene of the skierniewice isolate of plum pox virus (ppv-s) has been amplified using the reverse transcription--polymerase chain reaction (rt-pcr), cloned and sequenced. the nucleotide sequence of the gene and the deduced amino-acid sequence of ppv-s cp were compared with those of other ppv strains. the nucleotide sequence showed very high homology to most of the published sequences. the motif: asp-ala-gly (dag), important for the aphid transmissibility, was present in the a ...19947913278
adventitious pestivirus rna in live virus vaccines against bovine and swine virus vaccines against bovine and porcine diseases were examined for the presence of adventitious pestivirus rna or pestiviruses by reverse transcription-polymerase chain reaction (pcr). pestivirus rna was detected in the live virus vaccines against akabane disease, ibaraki disease, infectious bovine rhinotracheitis, porcine parvovirus infection, transmissible gastroenteritis and japanese encephalitis. pestivirus rna or pestivirus in the fetal bovine serum used to grow the host cells used t ...19957762264
sensitive non-radioactive nucleic acid hybridization assay for plum pox virus detection.a new non-radioactive sandwich hybridization assay was designed to simplify the analysis of a large number of plant samples. plant material was homogenized in 0.5% sds and added directly to the hybridization reaction, in which a pair of identifying probes were used. one of the probes was biotinylated capture rna specific for plum pox virus (ppv) strain sk-68; the other rna probe was synthesized from a plasmid bearing the adjacent sequence of this strain and was labelled with digoxigenin (dig). b ...19947709075
expression of the plum pox coat protein gene in transgenic nicotiana tabacum plants.plant expression vector pbi 121 containing the gene encoding coat protein of plum pox virus of the skierniewice isolate (cp ppv-s) was prepared (clone pcm1). the construct was used for transformation of nicotiana tabacum plants using an agrobacterium tumefaciens based system. about 82% of kanamycin resistant plant lines contained a transgene (the sequence of cp ppv-s) but only 81% of them actively expressed the ppv-s coat protein gene as measured by rt-pcr.19957653168
immunogenicity of poliovirus b and t cell epitopes presented by hybrid porcine parvovirus particles.we have analysed the potential capacity of hybrid porcine parvovirus (ppv) capsids to present foreign epitopes to the immune system. foreign sequences were introduced into the n and c termini of ppv vp2, which was previously shown to assemble spontaneously into parvovirus-like particles. the integrity of the c terminus was shown to be essential for preserving the structure of the capsid and therefore could not be used for epitope fusion. in contrast, insertion of sequences corresponding to t and ...19957561778
transmission by aphids of a naturally non-transmissible plum pox virus isolate with the aid of potato virus y helper component.two spanish plum pox virus (ppv) isolates, 5.15 and 3.3, were used in transmission experiments involving the aphid vector myzus persicae, with woody and herbaceous host plants. these isolates differ in the size of their coat protein (cp) and sequence analysis revealed that isolate 3.3 has a 15 amino acid deletion near the n terminus of the cp, affecting the same positions as in a previously reported non-aphid-transmissible ppv isolate from germany. aphid transmission experiments showed that isol ...19957561767
rna helicase activity of the plum pox potyvirus ci protein expressed in escherichia coli. mapping of an rna binding domain.the plum pox potyvirus (ppv) cylindrical inclusion (ci) protein fused to the maltose binding protein (mbp) has been synthesized in escherichia coli and purified by affinity chromatography in amylose resin. in the absence of any other viral factors, the fusion product had ntpase, rna binding and rna helicase activities. these in vitro activities were not affected by removal of the last 103 amino acids of the ci protein. however, other deletions in the c-terminal part of the protein, although leav ...19957538661
production and characterization of monoclonal antibodies to plum pox virus and their use in differentiation of mediterranean isolates.monoclonal antibodies (mabs) specific to plum pox virus (ppv) were prepared by fusing myeloma cell lines to spleen cells of mice immunized with purified virus, including virus prepared with protease inhibitors to preserve the integrity of the coat protein (cp). the characterized mabs could be used in elisa to differentiate several mediterranean ppv isolates differing in their geographical origin and cp size. at least seven antigenic sites could be established based on the recognition pattern and ...19947526822
[recent developments in the diagnosis of parapoxviruses].neutralizing and non-neutralizing monoclonal antibodies against parapoxviruses (ppv) were generated by immunizing balb/c-mice with gradient-purified ppv orf d-1701 or purified envelopes. epitope specificity studies identified three distinct epitopes localized in the virus envelope. these antigenic sites allowed a differentiation between orf and stomatitis papulosa viruses. for a rapid diagnosis of parapoxviruses transmission-electron microscopy, immunofluorescence- or immunoperoxidase-staining, ...19947519370
[return to estrus following first insemination in sow herds (incidence and association with reproductivity and various blood parameters)].as no systematic study has been done to get an accurate estimate of the incidence of return to oestrus after first insemination in sows in the netherlands, the objectives of this investigation were: 1) to obtain an estimate of the incidence of return to oestrus after insemination at the herd level; 2) to investigate the association between incidence of return to oestrus after first insemination and reproduction characteristics to get an impression of the economic importance. these objectives wer ...19937505958
interferon induction in peripheral blood mononuclear leukocytes of man and farm animals by poxvirus vector candidates and some poxvirus constructs.prototypes of three poxvirus genera--orthopoxvirus (opv), parapoxvirus (ppv), avipoxvirus (apv)--and newcastle disease virus (ndv) as a control, as well as three recombinant opv strains and one recombinant apv strain, were incubated in vitro with peripheral blood mononuclear leukocytes (pbml) of man, sheep and swine. antiviral activity was determined in pbml culture supernatants at different time intervals after virus cell interaction using a cytopathic effect inhibition bioassay. additionally, ...19957502485
virucidal short wavelength ultraviolet light treatment of plasma and factor viii concentrate: protection of proteins by antioxidants.the use of solvent/detergent mixtures and various forms of heat treatment to inactivate viruses has become widespread in the preparation of blood derivatives. because viruses that lack lipid envelopes and/or are heat resistant, eg, hepatitis a virus (hav) or parvovirus b19 may be present, the use of two methods of virus elimination that operate by different mechanisms has been advocated. we now report on short wavelength ultraviolet light (uvc) irradiation for virus inactivation and enhancement ...19957492794
properties of the active plum pox potyvirus rna polymerase complex in defined glycerol gradient a first step in the study of the replication of plum pox virus (ppv) rna, an in vitro virus-specific rna polymerase activity was characterized in a crude membrane extract (martin and garcia, 1991). in this study, we report the fractionation of the crude membrane extract by centrifugation in glycerol gradients. the sedimentation properties after different treatments of the crude extract and its insensitivity to micrococcal nuclease treatment suggest that the rna polymerase activity was localiz ...19957483826
antibody to porcine parvovirus in warthog (phacochoerus aethiopicus).haemagglutination inhibiting antibody to porcine parvovirus was shown to be widespread in all but one of the warthog populations sampled from south africa and zimbabwe rhodesia. in some instances titres as high as greater than or equal to 1/20 000 were detected.19807454234
effect of vaccinal and passive immunity on experimental infection of pigs with porcine group of 5 pigs was vaccinated twice at 6 and 8 weeks of age with an inactivated porcine parvovirus (ppv) vaccine. a 2nd group of 5 pigs was passively immunized at 9 weeks of age, and a 3rd group of 5 pigs served as nonimmunized controls. the immunity of all pigs was challenged with live ppv at 10 weeks of age. four vaccinated pigs with hemagglutinating-inhibiting (hi) antibody titer of 160 to 640 and 3 passively immunized pigs with hi titer of 80 to 160 were resistant to ppv infection. neit ...19807447129
response of conventionally raised weanling pigs to experimental infection with a virulent strain of porcine parvovirus.conventionally raised 6-week-old pigs were inoculated intranaslly and orally with porcine parvovirus. the pigs remained clinically normal for up to 17 days. they were viremic between 2 and 6 days after inoculation and had detectable hemagglutination-inhibiting titers to porcine parvovirus at 5 or 6 days after inoculation. virus was isolated from multiple tissues of pigs killed between 3 and 17 days after inoculation. viral antigen was demonstrated mainly in lymphoid tissues of these pigs. gross ...19807447115
transplacental infection and embryonic death following maternal exposure to porcine parvovirus near the time of conception.each of 20 gilts (principals) from a commercial swine herd free of antibody for porcine parvovirus (ppv) was exposed intranasally and orally to ppv at the onset of gestation. the gilts were killed and necropsied 22 +/- 1 days later to determine the effect of the virus on their embryos. an equal number of gilts (controls of the same status, from the same herd, and bred to the same boars, were treated similarly except for exposure to ppv. the following data were obtained at necropsy and from subse ...19807425850
reproductive performance of gilts exposed to porcine parvovirus at 56 or 70 days of gestation.a total of 18 pregnant gilts, which were free of antibody for porcine parvovirus (ppv), were exposed oronasally to ppv on either the 56th day (9 gilts) or 70th day (9 gilts) of the gestation to determine whether infection at these times would affect their reproductive performance. the gilts were either necropsied late in gestation or allowed to farrow, and their fetuses and pigs were tested for evidence of infection. gilts remained clinically healthy throughout the experiment, and none farrowed ...19817340578
ovine progressive pneumonia: experimental intrathoracic, intracerebral, and intra-articular infections.three groups of 4 lambs each were experimentally infected with an isolate of progressive pneumonia virus (ppv) by intracerebral, intra-articular, or intrathoracic routes of inoculation. an additional control group was sham-inoculated by all 3 routes with identically prepared, noninfected inoculum. sheep were killed 12 to 42 days after inoculation. a mild generalized leptomeningitis was found in 2 of the 4 lambs inoculated intracerebrally. a severe, proliferative synovitis with massive infiltrati ...19817325465
vaccination against porcine parvovirus infection. 19817304358
fetal infection with porcine parvovirus in herds with reproductive failure. 19817304357
survey of porcine parvovirus infection in swine fetuses and their dams at a minnesota abattoir.reproductive tracts were recovered from 209 sow and 32 gilt carcasses at slaughter; animals had been pregnant not less than 27 days. of 241 litters examined, 28 (11.6%) contained one or more porcine parvovirus (ppv)-infected fetuses, as determined by immunofluorescent microscopy. the frequencies in sow and gilt litters were 12.0% and 9.4%, respectively. the ppv antigen was detected in 219 of 334 (65.6%) dead or mummified fetuses and in 12 of 2,172 (0.5%) live fetuses examined. the 18 litters whi ...19817258807
accidental introduction of porcine parvovirus and talfan virus into a group of minimal disease gilts and their effects on reproduction. 19817248733
lesions resulting from inoculation of porcine foetuses with porcine utero inoculation of 15 sows at various stages of gestation with a local strain of porcine parvovirus (ppv) resulted in resorption, abortion or the birth of weak, dead, or mummified foetuses. histopathological lesions observed in foetuses of sows slaughtered at various post-inoculation intervals consisted of a perivascular inflammatory reaction primarily observed in the brain and kidneys. the presence and extent of the inflammatory reaction were dependent upon the age of the foetus at the tim ...19807231923
evaluation of a modified live-virus vaccine for the prevention of porcine parvovirus-induced reproductive disease in swine.each of 5 gilts was vaccinated im with modified live-virus (mlv) vaccine for porcine parvovirus (ppv), and 5 gilts were used as nonvaccinated controls. vaccinated gilts developed hemagglutination-inhibiting (hi) antibodies to ppv (titer of 320 to 1,280) by 2 weeks after vaccination. all gilts wee bred, and at about 40 days of gestation their immunity was challenged by intranasal and oral administration of a virulent strain of ppv. gilts were killed at about 84 days of gestation and their litters ...19807212434
comparison of antibody titers to porcine parvovirus in serum and ovarian follicular fluid. 19817196717
porcine parvovirus: serological examinations in pig breeding herds and ai boar centres.from several reports ppv is known to be world wide disseminated in pig herds. only few reports, however, are concerned about the prevalence of ppv infection among breeding animals within individual pig breeding herds. in the present work 1858 sows and boars from 53 conventional pig breeding herds and 731 sows from 73 spf pig breeding herds were examined for antibody to ppv, and the herds were grouped according to the prevalence of ppv antibody positive animals. more than 90% of the animals exami ...19827177795
studies on the multiplication of a porcine parvovirus.a porcine parvovirus has been characterized with regard to its replication in foetal porcine kidney cells and certain biophysical properties. electron microscopy of infected cells at selected times postinfection revealed that porcine parvovirus replication took place within or near a series of granular intranuclear inclusions which may be contiguous with cellular heterochromatin. developing virions were observed to aggregate into a nucleolar-like amorphous mass which gradually disrupted as cellu ...19827112892
duration and biological half-life of passively acquired colostral antibodies to porcine parvovirus.the duration of passive immunity and biological half-lives of passively acquired antibodies to porcine parvovirus (ppv) were determined in 4 pigs from each of 10 litters. all sows were randomly selected from a herd naturally infected with ppv. at parturition, blood and colostral samples from the 10 sows contained hemagglutination-inhibiting (hi) antibodies to ppv; the hi titers of colostrum were about 5 times higher than that of serum. the hi antibodies in serum and colostrum of sows were resist ...19827103222
effect of porcine parvovirus serostatus on the reproductive performance of mated gilts in an infected from 2 commercial swine operations (farm a and farm b) that were bred each week were tested for porcine parvovirus antibody. on farm a, 21.9% (weekly, 2% to 35%) of the 657 gilts tested over a 16-week period were seronegative within 1 week of mating. on farm b, 17.7% (weekly, o to 40%) of the 164 gilts tested over a 10 week period were seronegative within 1 week of mating. eighty-one gilts from farm a which were seronegative at time of mating were retested at the end of the gestation. of t ...19827103183
immunity to infection with porcine parvovirus in pigs inoculated with the attenuated ht- strain.swine were inoculated once with the attenuated ht- strain of porcine parvovirus. several months later they were challenged by oral inoculation with a field strain of the virus to examine an ability to prevent infection. after challenge inoculation unimmunized control swine exhibited an increase in antibody titer, viremia, and virus discharge. the virus was recovered from many organs. the swine preinoculated with the attenuated ht- strain, however, manifested none of these symptoms and were negat ...19827078661
establishment of an attenuated strain of porcine parvovirus by serial passage at low prepare a live virus vaccine strain for the prevention of porcine parvovirus infection, the 90hs strain, isolated from the brain of a stillborn porcine fetus, was subjected to the first 45 serial passages in swine kidney established (esk) cells of porcine kidney origin at 30-35 degrees c and to the 46th and later serial passages in the same cells as these at 32 degrees c. when swine were inoculated with the strain at the 38th passage level possessing such properties as expressed with rct/37+ ...19827078658
role of the rat in the transmission of porcine parvovirus.rats experimentally inoculated with porcine parvovirus (ppv) shed virus in excreta from 3 to 21 days. rats inoculated subcutaneously with ppv responded serologically with hemagglutination-inhibition titers (512-1,024). the ppv antigen was readily detected in lung and spleen 2 and 3 days after rats were inoculated and in liver and intestine, 4 days. the rats remained clinically healthy. rats given ppv orally or in drinking water either with ppv-infected cell culture fluid or swine fetal homogenat ...19827073064
assay for antibody in pig fetuses infected with porcine parvovirus. 19807004146
porcine parvovirus: virus purification and structural and antigenic properties of virion polypeptides.porcine parvovirus (ppv) was extensively purified from infected swine fetal homogenates by cacl2 precipitation followed by cscl density centrifugation. two species of particles possessing ppv-specific hemagglutinating activity were observed banding at densities of 1.39 and 1.30 g/ml, representing full and empty 20-nm virion particles, respectively. both classes of particles contained three major polypeptides. a, b, and c, with respective molecular weights of 83,000, 64,000, and 60,000. the amoun ...19836834473
farm studies of porcine parvovirus infection.epizootics of reproductive failure associated with porcine parvovirus infection were investigated on 38 farms. mummification was common to all epizootics. the mean number of mummified fetuses per affected litter was 3.1. mean number of pigs born alive for gilts and sows farrowing litters with mummified fetuses was 5.0, but for sows without mummified litters on the same farms it was 9.0. mummified fetuses were observed in aborted litters on 8 (21.1%) farms. gilts and sows that appeared pregnant b ...19836833101
a comparative survey using the gel diffusion precipitin and haemagglutination-inhibition tests for porcine parvovirus antibody. 19826805458
antibody responses of guinea-pigs, rabbits and pigs to inactivated porcine parvovirus vaccines.antibody responses were compared in guinea-pigs, rabbits and pigs following vaccination with inactivated porcine parvovirus (ppv) vaccines. mean ppv hemagglutination inhibition (hi) antibody titers of 52, 56 and 36 at 1 week after first vaccination and 896, 640 and 512 at 2 weeks after second vaccination were detected in guinea-pigs, rabbits and pigs, respectively. ppv vaccines prepared with greater concentrations of virus, as determined by hemagglutination (ha) units, and of aluminum hydroxide ...19846719818
increased litter size in gilts by intrauterine infusion of seminal and sperm antigens before breeding.three experiments were conducted to evaluate the effect of exposure of the uterus to semen at least 3 wk before breeding on subsequent reproductive performance. in exp. 1, uterine exposure to semen was performed three times. at least 3 wk elapsed between each treatment. control gilts received saline infusion. all gilts were bred by artificial insemination using semen from the same boars used for semen treatment. at farrowing, significantly more (10.35 vs 8.39) pigs/litter were produced by semen- ...19836682857
the pattern of endemic parvovirus infection in four pig herds.serological surveys were conducted on the gilts and adult sows in 4 herds endemically infected with porcine parvovirus. the study assessed the influence of the type of management of breeders on the spread of virus infection and the influence of endemic parvovirus infection on reproductive parameters of the herd. the practice of holding gilts and sows in groups did not reliably promote infection or maintain a 100% level of active immunity amongst adult sows in 2 of 3 group husbandry herds. in the ...19836626062
tissue culture infectivity assay for porcine parvovirus. 19846474785
evaluation of a gel diffusion precipitin test for porcine parvovirus.the use of a gel diffusion precipitin (gdp) test for the detection of porcine parvovirus (ppv) infection in pigs is described. the close correlation between gel diffusion precipitin and haemagglutination inhibiting (hi) antibody titres indicates that, with careful standardisation, a high level of sensitivity can be achieved with the gdp test and that it is a simple and relatively inexpensive alternative to the more commonly used hi test. experimental infection of 2 groups of pigs showed that gdp ...19836414450
isolation of porcine parvovirus (ppv) from swine herds affected by reproductive failure, and serologic evidence of infection in hungarian large swine herds. 19836331141
an inactivated, oil-emulsion vaccine for the prevention of porcine parvovirus-induced reproductive failure.pig fetuses inoculated at 45 days gestation with virulent porcine parvovirus (ppv) were harvested 10 days later. virus was extracted, inactivated with binary ethylenimine and the antigen suspension emulsified with mineral oil adjuvant. one dose of this vaccine, or two doses with a 14 day interval, stimulated high and long lasting serum antibody titres in gilts. vaccination caused no clinical reactions and lesions at injection sites were minor. vaccination of seronegative gilts at 40 days gestati ...19846326214
experimental infection of sheep by caprine arthritis-encephalitis virus and goats by progressive pneumonia virus.the lentiviruses, caprine arthritis-encephalitis virus (caev) and progressive pneumonia virus (ppv) of sheep, cause major diseases in their respective hosts; however, the infectivity of these viruses for closely related species has not been determined. experiments were conducted to determine whether caev would infect sheep and whether ppv would infect goats. upon inoculation with caev, lambs developed a nonsuppurative arthritis and antibody to caev, and the virus was isolated up to 4 months late ...19836318613
porcine parvovirus (p.p.v.): infection in boars. i. possibility of a genital localization in the boar after oronasal infection. 19836316695
porcine parvovirus infection: review and diagnosis in a sow herd with reproductive a commercial swine herd a rise was noted during the summer of 1981 in the number of repeat breeders, mostly four to eight weeks after serving. during the autumn there was a decrease in the litter size at birth and an increase in the number of stillborn and mummified piglets. several gilts and sows showed a seroconversion against porcine parvovirus (ppv), determined by the haemagglutination inhibition test (hi-test). characteristic pathological findings were seen in some maturely stillborn and ...19836314634
pseudorabies virus, porcine parvovirus, and porcine enterovirus interactions with the zona pellucida of the porcine embryo.porcine embryos (n = 93) were incubated on cell monolayers that had been previously inoculated with pseudorabies virus, porcine parvovirus (ppv), or each of 2 porcine enteroviruses. after 2, 24, or 48 hours of incubation, the embryos were fixed in glutaraldehyde and examined by electron microscopic procedures. it was found that pseudorabies virus adsorbed to the zona pellucida (zp) and entered sperm tracks in the zp. the ppv and both enteroviruses entered pores in the zp and were associated with ...19836307093
immunogenicity of bivalent vaccine for reproductive failure of swine induced by pseudorabies virus and porcine parvovirus. 19816277213
ovine progressive pneumonia: pathologic and virologic studies on the naturally occurring disease.pathologic and virologic studies were conducted on 13 mature ewes with serum precipitin antibodies to progressive pneumonia virus (ppv). pulmonary lesions of ovine progressive pneumonia were found in 4 sheep, a meningoencephalitis resembling visna in 1 sheep, chronic proliferative carpal arthritis in 2, and massive lymphoid proliferation in the mammary gland in 3. virus producing cytopathic effect typical of ppv was isolated from the lungs, mediastinal lymph node, spleen, and choroid plexus of 4 ...19816275756
laboratory evaluation of selected disinfectants as virucidal agents against porcine parvovirus, pseudorabies virus, and transmissible gastroenteritis virus.of a variety of disinfectants evaluated, only sodium hypochlorite and sodium hydroxide inactivated porcine parvovirus (ppv) after a 5-minute incubation period. after the same incubation time, pseudorabies and transmissible gastroenteritis viruses were inactivated by all of the disinfectants tested. when the incubation time was increased to 20 minutes, 2% glutaraldehyde and a double-strength concentration of a commercial formaldehyde preparation also inactivated ppv. formaldehyde vapor and ultrav ...19816269467
antibody response of pigs to inactivated monovalent and bivalent vaccines for porcine parvovirus and pseudorabies virus.groups of pigs vaccinated with an inactivated bivalent vaccine containing porcine parvovirus (ppv) and pseudorabies virus (prv) developed geometric mean titers (gmt) of humoral antibody for each of the viruses as high or slightly higher than those of other groups of pigs that were vaccinated with inactivated monovalent vaccines containing one or the other of the same viruses. an increase in gmt after challenge exposure of vaccinated pigs to live virus indicated that vaccination did not prevent v ...19806261613
morphological and immunological comparison of caprine arthritis encephalitis and ovine progressive pneumonia viruses.caprine arthritis encephalitis virus (caev) causes a variety of pathological conditions ranging from mild to very severe and from acute to chronic, depending upon the age of initial infection and other variables. although the virus has been reported to have properties of characteristic of retroviruses and to be related to maedi-visna virus (also called progressive pneumonia virus [ppv]), relatively little information about its morphological and immunological characteristics has been reported. we ...19816169845
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