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establishment of an attenuated strain of porcine parvovirus by serial passage at low temperature.to 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
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
effect of porcine parvovirus serostatus on the reproductive performance of mated gilts in an infected herd.gifts 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
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
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
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
comparison of antibody titers to porcine parvovirus in serum and ovarian follicular fluid. 19817196717
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
lesions resulting from inoculation of porcine foetuses with porcine parvovirus.in 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
accidental introduction of porcine parvovirus and talfan virus into a group of minimal disease gilts and their effects on reproduction. 19817248733
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
fetal infection with porcine parvovirus in herds with reproductive failure. 19817304357
vaccination against porcine parvovirus infection. 19817304358
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
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
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
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
effect of vaccinal and passive immunity on experimental infection of pigs with porcine parvovirus.one 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
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
properties of the active plum pox potyvirus rna polymerase complex in defined glycerol gradient fractions.as 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
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
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
[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
[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
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
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
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
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
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
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
adventitious pestivirus rna in live virus vaccines against bovine and swine diseases.live 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
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
porcine parvovirus associated with cutaneous lesions in piglets. 19947948207
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
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
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
[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
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
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
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
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
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
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
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
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
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
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
[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
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
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
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
financial evaluation of vaccination and testing alternatives for control of parvovirus-induced reproductive failure in swine.to identify the preferable testing and vaccination strategy for control of porcine parvovirus (ppv) during a 6-month period.19968617643
the use of respiratory-tract cultures in the diagnosis of invasive pulmonary aspergillosis.to define the role of lower-respiratory-tract cultures in the diagnosis of invasive pulmonary aspergillosis (ipa) in immunocompromised hosts.19968629651
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
print-capture pcr: a simple and highly sensitive method for the detection of plum pox virus (ppv) in plant tissues. 19968668554
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
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
diagnosis of fetal infection with porcine parvovirus by in situ hybridization.in 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
age-specific prevalence of porcine parvovirus antibody in feral pigs from a site in the northern territory. 19958787527
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 children.to 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
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
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
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
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
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
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
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
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
recombinant parvovirus-like particles as an antigen carrier: a novel nonreplicative exogenous antigen to elicit protective antiviral cytotoxic t cells.to 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
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
comparison of two different methods for inactivation of viruses in serum.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
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
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
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
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
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
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
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
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
specific oligonucleotide primers for the direct detection of plum pox potyvirus-cherry subgroup.a specific polymerase chain reaction assay was developed for direct identification of the distinct subgroup of plum pox potyvirus (ppv) isolates from cherry trees (ppv-cherry, ppv-c) and its differentiation from other known subgroups of ppv. the specificity of the assay is based on using a pair of primers whose nucleotide sequences are located on the coat protein gene of ppv-sour cherry (soc) at regions of high nucleotide divergence between ppv-soc and other isolates of ppv. the technique will b ...19989562418
routine diagnosis of herpes simplex virus (hsv) encephalitis by an internal dna controlled hsv pcr and an igg-capture assay for intrathecal synthesis of hsv antibodies.the development of antiviral therapy increases the need for rapid, sensitive and reliable methods or combination of methods for diagnosis and monitoring herpes simplex encephalitis, hse.19989562858
detection of challenge virus in fetal tissues by nested pcr as a test of the potency of a porcine parvovirus vaccine.to estimate the potency of a porcine parvovirus (ppv) vaccine, three vaccinated and three non-vaccinated pregnant gilts were infected with ppv and the distribution of the virus was studied in the tissues of their 51 fetuses. virus detection was attempted using haemagglutination (ha) and immunofluorescence (if) assays, as well as by standard (single) and nested polymerase chain reactions (pcr). none of the detection methods yielded positive results when used to test for the presence of virus in s ...19989563172
a recombinant virus-like particle system derived from parvovirus as an efficient antigen carrier to elicit a polarized th1 immune response without adjuvant.hybrid virus-like particles (vlp) were prepared by self-assembly of the modified porcine parvovirus (ppv) vp2 capsid protein carrying a cd8+ or cd4+ t cell epitope. immunization of mice with a single dose of these hybrid pseudo-particles, without adjuvant, induced strong cytotoxic t lymphocyte and t helper (th) responses against the reporter epitope. the th response was characterized by a th1 phenotype. we also analyzed in vitro the uptake mechanism of these parvovirus-like particles and the pro ...19989565380
susceptibility of peach gf 305 seedlings and selected herbaceous plants to plum pox virus isolates from western slovakia.the susceptibility of peach gf 305 seedlings and herbaceous plants to five plum pox virus (ppv) isolates from orchards of western slovakia was investigated. ppv was isolated from diseased plum, apricot and peach trees, and transmitted by chip-budding to peach gf 305. the herbaceous plants were infected by mechanical inoculation. the transmission was analysed by symptomatology and double sandwich enzyme-linked immunosorbent assay (das-elisa). infected peaches developed leaf distortion, tissue cle ...19979607094
development of an antigen presentation system based on plum pox potyvirus.the development of an antigen presentation system based on the plum pox potyvirus (ppv) is here described. the amino-terminal part of ppv capsid protein was chosen as the site for expression of foreign antigenic peptides. modifications in this site were engineered to avoid the capability of natural transmission by aphids of this ppv vector. as a first practical attempt, different forms of an antigenic peptide (single and tandem repetition) from the vp2 capsid protein of canine parvovirus (cpv) w ...19989607317
nicotiana benthamiana plants transformed with the plum pox virus helicase gene are resistant to virus infection.nicotiana benthamiana domin. plants were transformed with the cytoplasmic inclusion protein (ci) gene of plum pox potyvirus (ppv) to investigate, whether this non-structural protein would be able to confer resistance. the ci protein is an rna helicase, which contains a conserved nucleotide binding motif (ntbm) and plays an important role in viral replication. two gene constructions were developed for plant transformation. the first contains the original coding sequence of the ci gene under the c ...19989617773
mapping the antigenic structure of porcine parvovirus at the level of peptides.the antigenic structure of the capsid proteins of porcine parvovirus (ppv) was investigated. a total of nine linear epitopes were identified by pepscan using porcine or rabbit anti-ppv antisera. no sites were identified with a panel of neutralising monoclonal antibodies (mabs). all epitopes were located in the region corresponding to the major capsid protein vp2. based on this information, and on analogy to other autonomous parvoviruses, 24 different peptides were synthesised, coupled to keyhole ...19989620208
use of modified plum pox virus coat protein genes developed to limit heteroencapsidation-associated risks in transgenic plants.aphid transmission of a non-aphid-transmissible strain of zucchini yellow mosaic virus (zymv-nat) occurs in transgenic plants expressing the plum pox potyvirus (ppv) coat protein (cp) gene. heteroencapsidation has been shown to be responsible for this modification in the epidemiological characteristics of the infecting virus. in order to prevent this biological risk, several modified ppv cp constructs were produced that were designed to interfere with heteroencapsidation itself or to block aphid ...19989634095
evidence for incomplete replication of a penguin poxvirus in cells of mammalian origin.the recent discovery of a novel poxvirus [penguin-pox virus (ppv)] from jackass penguins offers the potential of a unique candidate vaccine vector for use in mammals. infectivity studies were therefore undertaken using a number of mammalian cell lines and chick embryo fibroblasts (cef). it was shown that the simian cv-1 cell line was able to support replication of the ppv dna, but no infectious progeny virus could be recovered from the infected cells. electron microscopy was used to establish th ...19989680125
changing disease patterns in focal brain lesion-causing disorders in aids.to assess temporal trends of the different disorders causing focal brain lesions (fbl) in hiv-infected patients and to examine the reliability of the u.s. centers for disease control and prevention (cdc) criteria for presumptive diagnosis of toxoplasmic encephalitis (te) for the years 1991 to 1996.19989704942
strain variability of plum pox virus isolates from western slovakia.leaf tissues of stone fruit trees (plum, apricot, peach and myrobalan) carrying symptoms of plum pox virus (ppv) infection and of peach gf 305 seedlings and nicotiana benthamiana infected experimentally with ppv were assayed for ppv by polymerase chain reaction (pcr). the expected 243 bp pcr products were subjected to restriction fragment length polymorphism (rflp) analysis with restriction endonucleases alui and rsai. all of the pcr products contained the alui site. the rsai restriction profile ...19989770072
analysis of genomic rearrangement and subsequent gene deletion of the attenuated orf virus strain d1701.the orf virus (ov) strain d1701 belongs to the genetically heterogenous parapoxvirus (ppv) genus of the family poxviridae. the attenuated ov d1701 has been licensed as a live vaccine against contagious ecthyma in sheep. detailed knowledge on the genetic structure and organization of this ppv vaccine strain is an important prerequisite to reveal possible genetic mechanisms of ppv attenuation. the present study demonstrates a genomic map of the approximately 158 kbp dna of ov d1701 established by ...19989784065
determination of adequate moisture content for efficient dry-heat viral inactivation in lyophilized factor viii by loss on drying and by near infrared spectroscopy.a requirement for a minimal threshold level of moisture in order for efficient virus inactivation to occur during dry heat treatment of freeze-dried coagulation factor concentrates is described. techniques used to determine moisture content during heating were loss on drying and karl fischer. the loss on drying was suspected to have occasional errors as a result of sample preparation being influenced by interference from atmospheric moisture. therefore, a non-invasive, non-destructive method for ...19989811517
inactivation of viruses by beta-propiolactone in human cryo poor plasma and igg concentrates.virus inactivation by cold treatment with beta-propiolactone (bpl) was investigated in human cryo poor plasma and purified igg concentrates spiked with relevant human viruses or appropriate animal model viruses. the samples were treated with 0.1 or 0.25% bpl for 300 or 480 min, respectively. residual infectivity was determined by standard microtitration assays on tissue culture cells. the inactivation of all viruses tested was more effective in igg than in plasma. igg: r1=4-5.5 log10 for vesicul ...19989811521
serosurvey of selected viral and bacterial diseases in wild swine from oklahoma.blood samples collected from 120 wild swine (sus scrofa) in thirteen oklahoma (usa) counties during 1996 were tested for antibodies against six viral and two bacterial diseases. no antibodies to swine brucellosis, pseudorabies, transmissible gastroenteritis, and vesicular stomatitis were detected. antibody titers to one or more leptospiral serovars were found in 44% of the samples, the two most frequent serovars being leptospira interrogans serovars bratislava (29%) and pomona (27%). antibody ag ...19989813859
prenatal diagnosis of congenital cytomegalovirus infection.we report here the results of a study on the prenatal diagnosis of congenital cytomegalovirus (cmv) infection. the study was carried out by both pcr and virus isolation from amniotic fluid (af) for 82 pregnant women at risk of transmitting cmv for the detection of (i) seroconversion to cmv immunoglobulin g (igg) positivity during the first trimester of pregnancy, (ii) symptomatic cmv infection in the mother during the first trimester of pregnancy or intrauterine growth retardation detected by ul ...19989817869
properties of a virus causing mosaic and leaf curl disease of celosia argentea l. in nigeria.a sap transmissible virus, causing mosaic and leaf curl disease of celosia argentea, was isolated at vegetable farms in amuwo odofin, tejuoso, and abule ado, lagos, nigeria. the virus had a restricted host range confined to a few species of the amaranthaceae, chenopodiaceae and solanaceae families. it failed to infect several other species of the aizoaceae, brassicaceae, cucurbitaceae, fabaceae, lamiaceae, malvaceae, poaceae and tiliaceae families. the virus was transmitted in a non-persistent m ...19989842442
development of a pcr-based method coupled with a microplate colorimetric assay for the detection of porcine parvovirus and application to diagnosis in piglet tissues and human plasma.a new method for porcine parvovirus (ppv) diagnosis was developed. the method is based on polymerase chain reaction (pcr) amplification followed by hybridization and colorimetric detection of pcr products in microwell plates. a highly specific and sensitive amplification step was ensured by primers carefully selected in the vp2 structural gene and optimized pcr conditions. uracyl-dna-glycosylase (udg) in combination with dutp was used to avoid false-positive results, and 100 copies of internal c ...19989843658
validation of the heat treatment step used in the production of diaspirin crosslinked hemoglobin (dclhb) for viral inactivation.a series of experiments was performed to assess the ability of the heat treatment step used in the manufacture of diaspirin crosslinked hemoglobin (dclhb) to inactivate viruses. in-process solutions (reaction mixtures after the crosslinking process) from six different manufacturing lots were used as test media in a 1:680 scaled down system in which the key process parameters used in the large scale production were duplicated. the inactivation of five different viruses (bovine viral diarrhea viru ...19989844723
ultrastructural localization of nonstructural and coat proteins of 19 potyviruses using antisera to bacterially expressed proteins of plum pox potyvirus.antisera to the bacterially expressed nonstructural proteins (nsp) hc-pro, ci, nia, and nib and the coat protein (cp) of plum pox potyvirus (ppv) were used for analysing the composition of virus-induced cytoplasmic and nuclear inclusions by electron microscopy. the antisera reacted with nsp and cp of ppv on immunogold-labelled ultrathin sections. antiserum to cp reacted with virions of seven out of 18 other potyviruses. cp was distributed throughout the cytoplasm of infected cells. antisera to p ...19989856098
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