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swine diseases transmissible with artificial insemination.the transport of fresh and frozen semen to be used for artificial insemination creates a mode of disease transmission between farms. normally, semen contains a number of nonpathogenic bacterial contaminants; however, excessive bacterial contamination can result in infertile matings. contamination with a known pathogen, eg, brucella suis, could initiate a serious outbreak of disease in a recipient herd. methods to minimize bacterial contamination of semen include sanitary collecting and processin ...19846090372
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
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
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
[occurrence of porcine parvovirus infection in switzerland and a new method of virus demonstration using immune electron microscopy]. 19846098102
[parvovirus infection in pigs: incidence and prevention. the diessen group veterinarian practice].a trial is reported, which was carried out to find an answer to two questions: to which extent do parvovirus-infections occur and what is the effect of a single porcine parvovirus vaccination? parvovirus was found to be enzootic on the farms included in the trial, whereas a singled vaccination was shown to be effective with regard to the prevention of lesions due to porcine parvovirus infections.19846095485
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
immunogenicity of bivalent vaccine for reproductive failure of swine induced by pseudorabies virus and porcine parvovirus. 19816277213
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
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
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
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
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
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
assay for antibody in pig fetuses infected with porcine parvovirus. 19807004146
[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
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
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
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
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
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
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
print-capture pcr: a simple and highly sensitive method for the detection of plum pox virus (ppv) in plant tissues. 19968668554
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
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
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
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
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
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
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
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
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
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
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
[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
fetal infection with porcine parvovirus in herds with reproductive failure. 19817304357
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
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
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
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
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
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
porcine parvovirus infection: review and diagnosis in a sow herd with reproductive failure.in 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
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
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
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
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
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
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
nucleotide sequence of the putative replicase gene of the sour cherry strain of plum pox potyvirus.the complete nucleotide sequence of the nib coding region of the sour cherry strain of plum pox potyvirus (ppv-soc) has been determined. it consists of 1554 nucleotides and encodes a putative replicase protein of 518 amino acids. sequence identity scores between nib of ppv-soc and other isolates of ppv are significantly low (c. 78%). many of the nucleotide substitutions, however, are silent. ppv-soc differs from isolates of ppv-d, ppv-m and ppv-e1 amar at multiple amino acid positions that are c ...19989856106
susceptibility to recombination rearrangements of a chimeric plum pox potyvirus genome after insertion of a foreign gene.infectious rna transcripts were generated from a chimeric cdna clone of the plum pox potyvirus (ppv) genome containing the bacterial beta-glucuronidase (gus) gene inserted between the sequences coding for the p1 and hc proteins. an artificial cleavage site specific for the nia viral proteinase was engineered between the gus and hc sequences to produce free gus and hc proteins. the resulting virus ppvgus/ was stably maintained during the first round of infection, although plants remained symptoml ...19989870586
enumeration of marine viruses in culture and natural samples by flow cytometryflow cytometry (fcm) was successfully used to enumerate viruses in seawater after staining with the nucleic acid-specific dye sybr green-i. the technique was first optimized by using the phaeocystis lytic virus ppv-01. then it was used to analyze natural samples from different oceanic locations. virus samples were fixed with 0.5% glutaraldehyde and deep frozen for delayed analysis. the samples were then diluted in tris-edta buffer and analyzed in the presence of sybr green-i. a duplicate sample ...19999872758
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
reproduction of lesions of postweaning multisystemic wasting syndrome in gnotobiotic piglets.neonatal gnotobiotic piglets were inoculated with tissue homogenates and low- and high-passage cell culture material to determine if the lesions of the newly described porcine postweaning multisystemic wasting syndrome (pmws) could be reproduced. for this, 17 3-day-old gnotobiotic piglets were inoculated intranasally with pelleted chloroform-treated, filtered extracts from cell cultures, filter-sterilized homogenates of lymphoid tissue from pmws-affected piglets, or control materials. piglets we ...19999925205
mitotic stability of infection-induced resistance to plum pox potyvirus associated with transgene silencing and dna methylation.plum pox potyvirus (ppv) infection of transgenic nicotiana benthamiana plants that expressed the ppv nib rna replicase carrying a gly to val mutation at the gdd motif (nibv lines) induced a phenotype of virus resistance and transgene silencing, which was not transmissible to the progeny after self-fertilization (h. s. guo and j. a. garcía, mol. plant-microbe interact. 10:160-170, 1997). here, we demonstrate that the induced resistance of nibv plants is mitotically stable after plant propagation ...19999926412
reproductive tract infections in primary healthcare, family planning, and dermatovenereology clinics: evaluation of syndromic management in morocco.to determine where and with what symptoms women seek care for reproductive tract infections (rti) in morocco and to guide allocation of resources for training and treatment for rtis.199810023358
some results of 50 years of research on the resistance to plum pox virus.over 300 references on the resistance of stone fruit species to plum pox virus (ppv) have been utilized for the summarization of relevant information in this review. methods of testing ppv resistance, procedures of evaluation and characterization of ppv resistance as well as breeding of ppv-resistant cultivars are briefly discussed. altogether 370 cultivars, hybrids and clones of plum, peach, apricot, nectarine and wild prunus species are tabulated together with the authors who have reported on ...199810073219
relationship between concentration of plum pox virus and content of pigments in virus-infected symptomatic apricot leaves.besides other factors, occurrence of plum pox virus (ppv)-caused spots and mosaic symptoms on leaves of stone fruits are known to influence important physiological functions including production of assimilates. apricot (prunus armeniaca l.) seedlings were used as a test material for typical manifestation of symptoms of the disease on the foliage. the relations of the abovementioned visual symptoms to the virus and pigments concentrations in leaves have so far not been known sufficiently. we dete ...199810073220
comparison of different methods of rna isolation for plum pox virus detection by reverse transcription-polymerase chain reaction.the diagnosis of plum pox virus (ppv) is still considered one of the most important aspects of the "sharka" problem. in fact, different studies demonstrated an uneven distribution of the virus in infected trees due to a high variability in virus concentration. these aspects complicate the ppv diagnosis. to date, biological, serological and molecular assays have been successively developed in order to obtain sensitive and efficient ppv detection techniques. in particular, the polymerase chain rea ...199810073221
investigation on the plum pox virus resistance in different apricot genotypes.in our three-year investigation, 164 apricot trees of different old german varieties cultivated in the mansfelder land region were tested for the plum pox virus (ppv) resistance by double grafting in greenhouse conditions using an isolate of ppv d strain from our region. we selected 25 genotypes with quantitative resistance and two with immunity. the first results of field trials are comparable with those from greenhouse. with cvs. virosia and brevira, two local quantitatively resistant varietie ...199810073222
characterization of plum pox virus isolates from slovakia.plum pox virus (ppv) isolates from stone-fruit trees (plums, myrobalans, apricots and peaches) from orchards and gardens were characterized. to characterize their biological properties, several ppv isolates were transmitted by chip budding to gf 305 seedlings and mechanically to selected herbaceous test plants. the isolates differed in severity of infection, host range and symptomatology. a subgroup differentiation of 43 isolates from 22 localities of western and middle slovakia was accomplished ...199810073223
aphid species--vectors of plum pox virus.plum pox virus (ppv) is widely spread by natural vectors present in plum orchards. the efficiency of transmission is dependent on the frequency of the occurrence of vectors and the cultivar susceptibility to this pathogen. having in view that ppv has a wide range of annual and multiannual host plants and vectors, there is great concern for obtaining ppv-resistant cultivars. this report deals with the following vectors: hyalopterus pruni, brachycaudus cardui, brachycaudus helichrysi. myzus persic ...199810073225
high resistance and control of biological risks in transgenic plants expressing modified plum pox virus coat protein.transgenic plums transformed with the plum pox virus coat protein (ppv cp) gene displayed a resistance to the sharka disease (ravelonandro et al., 1997). however, the expression of ppv cp in transgenic plants may lead to complementation of deficient characteristic of an incoming potyvirus. indeed, an aphid-intransmissible strain of zucchini yellow mosaic virus (zymv-nat) could be transmitted when encapsidated by the engineered ppv cp (lecoq et al., 1993). to control such a risk, new ppv cp const ...199810073226
mineral nutrition of plum trees as an important factor of protection against plum pox virus disease.the experimental results obtained from a fruit garden at krajné pointed out a different content of macrobiogenic elements in the leaves of plum trees infected with plum pox virus (ppv) as compared to healthy ones. mineral nutrition of diseased trees was characteristic by lower relational values of topical levels of macrobiogenic elements especially those of n/p, n/k, (ca + mg)/k, and (n/p)/(n/k).199810073227
preliminary report on the apparent breaking of resistance of a transgenic plum by chip bud inoculation of plum pox virus ppv-s.five transgenic clones of prunus domestica l. containing plum pox virus (ppv) coat protein (cp) gene and one non-transformed control clone were challenged with ppv-s in the field. symptoms developed on c2, c3, c4, c6 and b70146 but not c5 trees inoculated by chip budding (cbi) (2/2, 2/2, 1/1, 2/2 and 2/2, positive/inoculated) in the first summer after inoculation. however, in the second year, symptoms appeared on cbi c5 trees. the presence of the virus in the plants was confirmed by enzyme-linke ...199810073228
new results concerning the plum pox virus epidemiology and resistance of plum cultivars, hybrids and rootstocks.our recent results on the plum pox virus (ppv) epidemiology show that ppv spreads very rapidly in plum tree plantations in the contaminated areas. a clearing of the ppv-infected trees reduces significantly the spread of the virus but does not eliminate the disease. some plum tree cultivars, hybrids and rootstocks (scoldus, alina, cristi, bn 1/8fl, bn 2gr. etc) showing field resistance could not be infected with ppv by natural way. however, they could be infected with ppv by artificial inoculatio ...199810073229
production of a monoclonal antibody specific to the el amar strain of plum pox virus.plum pox virus (ppv) isolates are grouped into three clusters differentiated by biological, serological, molecular and epidemiological characteristics: marcus (m), dideron (d) and cherry (c). the el amar (ea) isolate that does not fit any of the above groups is also known. monoclonal antibodies (mabs) that specifically recognize m, d, and c strains of ppv are already available. to complete the set of ppv strain-specific serological reagents, mabs against the ea isolate were raised by immunizing ...199810073230
detection and serotyping of mediterranean plum pox virus isolates by means of strain-specific monoclonal antibodies.plum pox virus (ppv) is a major threat to the expanding mediterranean stone fruit industry. in order to control the plum pox disease it is of utmost importance to detect early ppv foci and to identify the ppv isolates involved. a survey was therefore carried out in albania, cyprus, egypt, greece, italy and turkey by a double-antibody sandwich enzyme-linked immunosorbent assay (das-elisa) with the following monoclonal antibodies (mabs): 5b (universal), 4dg5 (ppv-d-specific), al (ppv-m-specific), ...199810073231
molecular variability of czech plum pox virus isolates.seventy-two czech plum pox virus (ppv) isolates from different hosts were tested by double-antibody sandwich enzyme-linked immunosorbent assay (das-elisa). in addition, the coat protein mobility and the rsai restriction fragment length polymorphism (rflp) pattern of reverse transcription-polymerase chain reaction-(rt-pcr) amplified coat protein (cp) gene fragment of the isolates were analysed. both ppv-d and ppv-m serotypes were found in the czech republic. the results obtained by these differen ...199810073232
testing of plum germplasm for sensitivity to plum pox.a long-term orchard experiment with a broad assortment of plum cultivars aimed to screen their sensitivity to plum pox virus (ppv) was established in 1991. for this purpose, 207 cultivars to be artificially infected with ppv at a permanent site were chosen. the serotype m of ppv from a tree of cv. domestic prune, which had not been contaminated by other viruses, was used as a source of the infection. three buds infected with ppv were budded on 1-year-old trees. in the course of experiment the fo ...199810073233
detection of plum pox virus in apricot seeds.twelve different apricot selection trees from a germplasm collection naturally infected with plum pox virus (ppv) were chosen to investigate the role of seeds in the epidemiology of this dangerous pathogen. all the considered plants showed typical symptoms on leaves and fruits and were positive in enzyme-linked immunosorbent assay (elisa). the virus was characterized by immunocapture reverse transcription-polymerase chain reaction (ic-rt-pcr) followed by restriction fragment length polymorphism ...199810073234
relative concentration of plum pox virus in leaves and flowers of some prunus species and cultivars.the relative concentration of plum pox virus (ppv) in leaves and flowers of plum, damson, myrobalan, blackthorn, apricot and peach trees was determined by enzyme-linked immunosorbent assay (elisa) and expressed as the lowest dilution with positive reaction. significant differences in relative ppv concentration were found in leaves among individual prunus species naturally or artificially infected with the virus. the highest relative ppv concentration was found in blackthorns (7.81 x 10(-4)), com ...199810073235
restriction fragment length polymorphism differentiation of plum pox virus isolates.reverse transcription-polymerase chain reaction (rt-pcr) technique and restriction fragment length polymorphism (rflp) analysis were used to analyse six isolates of plum pox virus (ppv). whole coat protein (cp) gene was amplified in four isolates using the unipoty-polyt primer pari. ppv-d was identified by rflp analysis using sfui and drai enzymes in two of the isolates. two isolates of ppv-m strain yielded rt-pcr products which could not be digested by the two enzymes. other isolates were subje ...199810073236
characterization of phenotype resistance to plum pox of transgenic plums expressing plum pox virus capsid gene.resistance to plum pox virus (ppv) infection can be obtained in transgenic plants that express the virus capsid gene. an agrobacterium-mediated transformation was used to introduce the ppv capsid gene into prunus domestica plants. over 11 regenerated plants (clones) were observed for the development of the disease symptoms and analysed for the presence of ppv by enzyme-linked immunosorbent assay (elisa), western blot analysis, and reverse transcription-polymerase chain reaction (rt-pcr) through ...199810073237
agroclimatical analysis of plum pox virus spread in slovakia.in this report, the plum pox virus (ppv) spread from the point of view of agroclimatical conditions on the territory of slovakia is analysed. the worst condition for the ppv spread was found in a warm macroregion. the air temperature sum in this macroregion during vegetative period ranged from 2400 to 3100 degrees c. the worst condition for the ppv spread was found in dry subregions of the macroregion. these were defined by differences between potential evapotranspiration and rainfall sums which ...199810073238
detection of plum pox virus by enzyme-linked immunosorbent assay in some apricot and peach varieties and hybrids in romania.plum pox virus (ppv) is a potyvirus widely spread in many species of the prunus genus such as plum, apricot, peach, sweet cherry and others. this potyvirus causes great damage to stone fruit trees in romania and other european countries as hungary, italy, czech republic, france, spain, greece, turkey, and slovak republic. the research station for fruit tree growing baneasa in bucharest has realized many studies on the epidemiology and spread of ppv and also on the disease symptomatology and dete ...199810073239
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
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
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
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