TitleAbstractYear(sorted ascending)
[occurrence of porcine parvovirus infection in switzerland and a new method of virus demonstration using immune electron microscopy]. 19846098102
biological assay of attenuated strain nadl-2 and virulent strain nadl-8 of porcine parvovirus.attenuated strain nadl-2 and virulent strain nadl-8 of porcine parvovirus (ppv) were titrated in vivo and in vitro under similar conditions to provide a better understanding of some of the factors involved in virulence of ppv in causing maternal reproductive failure of swine. both strains cause fetal death when they are injected directly into fetal fluids, but only strain nadl-8 does so when administered to pregnant swine. the strains were tested for their hemagglutinating activity (ha), median ...19846098200
oronasal and intramuscular vaccination of swine with a modified live porcine parvovirus vaccine: multiplication and transmission of the vaccine attenuated strain nadl-2 of porcine parvovirus (ppv) has been used at the 54th cell culture passage as a modified live-virus (mlv) vaccine. the present study was conducted to determine the minimum immunizing dose of mlv, the extent of mlv multiplication in swine tissues, and its transmission from swine administered mlv oronasally or intramuscularly. immune response to mlv was dose dependent and swine responded to as little as 10(2) median cell-culture infective doses (ccid50). a 10(5) ccid50 ...19846098202
antibody responses of guinea-pigs, rabbits and pigs to inactivated porcine parvovirus vaccines.antibody responses were compared in guinea-pigs, rabbits and pigs following vaccination with inactivated porcine parvovirus (ppv) vaccines. mean ppv hemagglutination inhibition (hi) antibody titers of 52, 56 and 36 at 1 week after first vaccination and 896, 640 and 512 at 2 weeks after second vaccination were detected in guinea-pigs, rabbits and pigs, respectively. ppv vaccines prepared with greater concentrations of virus, as determined by hemagglutination (ha) units, and of aluminum hydroxide ...19846719818
pasteurization of antihemophilic factor and model virus inactivation studies.heating sterilized albumin preparations at 600 degrees c for 10 hours has historically been shown to yield a hepatitis-free, efficacious product. we have evaluated such a pasteurization procedure with ahf preparations. procoagulant activity and fibrinogen stability were dependent on the amount of sucrose used as a stabilizer. flash pasteurization at 72 degrees c was evaluated and was found to be detrimental to ahf. effect of sucrose concentration was shown on the inactivation kinetics of porcine ...19853931293
potentiating effect of adjuvants on humoral immunity to porcine parvovirus vaccines in guinea pigs.fourteen different adjuvants, given either in single or combined form with another compound were compared in guinea pigs for their ability to potentiate humoral immunity to porcine parvovirus (ppv) antigen after 2 vaccinations. two injections were given, the second 3 weeks following the initial vaccination. antibody concentrations to ppv in sera from injected animals were measured over a 5-week period by the hemagglutination inhibition test. at the conclusion of the experiment, guinea pigs injec ...19854002607
identification and characterization of a porcine parvovirus nonstructural polypeptide.sera from porcine parvovirus (ppv)-infected swine fetuses immunoprecipitated and 84- to 86-kilodalton polypeptide in addition to the a and b virion structural proteins. this polypeptide, designated ns-1, was present in ppv-infected cell lysates but not in purified virions. partial proteolysis mapping revealed that ns-1 was not related to the a and b viral structural proteins. all three proteins in infected cells were phosphorylated at serine residues, and ns-1 also contained phosphothreonine. fr ...19854020958
[study of porcine parvovirus antibodies on a breeding farm].serological examination of porcine parvovirus (ppv) haemagglutinating antibodies is reported in replacement gilts after a ppv infection on a large farm. it seems that ppv is no longer active on the farm after ppv infection.19854082161
precipitating antibodies in experimental visna and natural progressive pneumonia of sheep.serological responses of icelandic sheep experimentally infected with visna virus (vv) were contrasted with responses in american targhee sheep naturally infected with progressive pneumonia virus (ppv). precipitating antibodies assayed by immunodiffusion were compared with the neutralising and complementing fixing antibody response. in experimental infections with vv, complement fixing and neutralising antibodies appeared early after infection and rose to high levels in all sheep, while precipit ...19852988088
kbsh parvovirus: comparison with porcine parvovirus.we compared the molecular, antigenic, and pathogenic properties of kbsh parvovirus to those of porcine parvovirus (ppv) isolate nadl-8. kbsh, propagated in swine testes cells in culture, possessed two major capsid polypeptides of 83 and 64 kilodaltons that were similar in size to those of ppv. kbsh-infected cells also contained an 86-kilodalton nonstructural polypeptide that was identical in size to the ppv nonstructural polypeptide (ns-1). the kbsh polypeptides were structurally similar but not ...19852991553
prenatal and preweaning deaths caused by pseudorabies virus and porcine parvovirus in a swine herd.sequential outbreaks of pseudorabies virus and porcine parvovirus infections were documented at a swine farm in southern minnesota. data for the prevalence of mummified fetuses born and the preweaning mortality were recorded over a 3-year-period. the farm was a farrow-to-finish facility, with breeding females housed in 4 groups according to their stage of pregnancy. the herd consisted of approximately 130 breeding females in december 1981, and expanded to 220 females during the 12 months of 1982 ...19852997093
persistence of passive immunity to porcine parvovirus. 19852998320
absence of porcine parvovirus transmission to man. 19853001979
porcine parvovirus: a serological survey in the united kingdom january 1984 to january 1985. 19853001999
parvovirus infection in pigs with necrotic and vesicle-like lesions.porcine parvovirus was isolated from many visceral organs and also from the brain, serum and skin specimens of swine with vesicular-like conditions. severe lesions were reported to have occurred in the mouth, on the tongue and snout, on the coronary band and in the interdigital spaces. also, parvoviral antigens were demonstrated, by immunofluorescence, in the outer layers of hair follicles in skin adjacent to coronary band lesions.19853006323
radioimmunoassay of adjuvant-associated porcine parvovirus using a monoclonal antibody in a nitrocellulose membrane system.a quantitative and simple indirect radioimmunoassay (iria) was developed for porcine parvovirus (ppv), employing a monoclonal antibody directed against ppv adsorbed to nitrocellulose membrane. the iria was equally sensitive to live or inactivated ppv. there was a linear relationship between membrane-bound radioactivity and ppv quantity within a range of 10-80 hemagglutinating (ha) units of virus. two commercially used adjuvants, aluminum hydroxide (ah) and carboxyvinyl polymer (cp), reduced boun ...19853009510
parvovirus-like particles associated with diarrhea in unweaned piglets.numerous parvovirus-like particles, 18 to 26 nm in diameter, were detected by electron microscopy in the intestinal contents of two to three week old piglets with mild to severe diarrhea, in six quebec pig herds. hemagglutination of guinea pig and african green monkey red blood cells was obtained with clarified intestinal contents. two isolates were found to be antigenically related to porcine and canine parvoviruses, while another differed from the porcine parvovirus using the hemagglutination- ...19852412678
antigenic relationships among autonomous parvoviruses.the antigenic relatedness of minute virus of mice (mvm), kilham rat virus (kr), h-1 virus (h-1), haemorrhagic encephalopathy of rats virus (her), porcine parvovirus (ppv), canine parvovirus (cpv), feline panleukopenia virus (fpv), goose parvovirus (gpv) and bovine parvovirus (bpv) was studied by immunofluorescence microscopy (fa) and by serum neutralization (sn). an antigenically related group comprising mvm, kr, her, ppv, cpv and fpv was recognized by fa and most reactions within the group were ...19862432167
establishment of the attenuated strain of porcine parvovirus for the live vaccine and its biological-immunological characteristics. 19863012173
interepizootic survival of porcine parvovirus.porcine parvovirus (ppv) was transmitted by direct contact between experimentally infected and susceptible pigs at 1 and 2 weeks, but not at 4, 8, 16, or 25 weeks, after experimental infection. in contrast, ppv was found to remain infectious for at least 14 weeks in uncleaned rooms previously vacated by experimentally infected pigs. these findings suggest that facilities contaminated by secretions and excretions of infected pigs may provide the major means by which ppv survives between episodes ...19863013820
efficacy of porcine parvovirus vaccines.three inactivated porcine parvovirus vaccines were tested for efficacy in 66 susceptible gilts. the gilts were challenged with virulent virus on the 40th day of gestation. all the vaccines provided excellent protection against fetal mortality despite insignificant serological responses to one of them. good protection was obtained with two of the vaccines even when the dose was substantially reduced. unvaccinated controls had very few viable fetuses.19863020765
[effect of maternal antibodies on the vaccination of young swine against porcine parvovirus (ppv)]. 19863021118
a solid phase fluorescent immunoassay for the rapid detection of virus antigen or antibodies in fetuses infected with porcine parvovirus.a solid phase fluorescent immunoassay using polyacrylamide beads coated with rabbit anti-porcine parvovirus antibodies has been developed and utilized in the diagnosis of porcine parvovirus infection. the antibody-coated beads (immunobeads) were used both to detect virus in mummified fetal tissues and to demonstrate specific antibodies in serum and ovarian follicular fluid. the immunobeads assay (iba) was as sensitive as elisa but more sensitive than virus isolation using tissue culture and haem ...19863006641
some epidemiological features and effects on reproductive performance of endemic porcine parvovirus infection.the time of development of demonstrable antibody to porcine parvovirus (ppv) was determined for 661 gilts entering the breeding herd in a 2800 sow intensive piggery; 13.2% of these gilts did not have detectable antibody to ppv when first introduced into the breeding herd at 25 to 26 weeks of age. exposure to ppv was found to vary in different sheds and even in different areas within a shed. gilts that developed antibody to ppv during the first third of pregnancy were not adversely affected. thos ...19863008694
porcine parvovirus: propagation in microcarrier cell culture and immunogenic evaluation in pregnant gilts.porcine parvovirus was propagated in pk-15 cells cultured in roller bottles or on microcarrier beads. after inactivation, the virus was used as antigen in the preparation of vaccines. the immunogenic potency and safety of the vaccines were evaluated in specific pathogen free pregnant gilts and guinea pigs. experimental challenge tests determined the efficacy of the vaccine in preventing porcine parvovirus transplacental infection. neither viral antigens nor specific antibodies were detected in f ...19863809732
study of the efficacy of an inactivated virus vaccine against porcine parvovirus.the efficacy of an inactivated virus vaccine against porcine parvovirus has been studied by immunizing 4 sows during pregnancy. a parvovirus virulent strain has been inoculated to these sows and to two other unvaccinated sows used as controls. the infection was performed between the 52nd and the 57th day of gestation. in the litters born from the vaccinated sows, 82% of the piglets were alive and normal. neither ppv antibodies nor antigen could be revealed in the stillborn fetuses born from the ...19863030182
vaccination of swine with an inactivated porcine parvovirus vaccine in the presence of passive immunity.a study was conducted to determine whether low hemagglutination inhibiting (hi) titers (1:5) for porcine parvovirus (ppv) block the development of immune response to a ppv vaccine. pigs with low (1:5), medium (1:10 or 1:20), or high (1:40 or 1:80) titers were obtained by iv injections with various amounts of ppv immune serum. pigs were inoculated with 1 or 2 doses of vaccine and were monitored for serum hi antibodies to ppv. pigs with low titers responded to vaccine just as well as did the seron ...19863949618
porcine parvovirus infection in a commercial piggery. 198616031279
desorption of porcine parvovirus from aluminum hydroxide adjuvant with subsequent viral immunoassay or hemagglutination assay.cell culture fluids containing porcine parvovirus were adjuvanted with varying concentrations of aluminum hydroxide gel. adsorption of virus and total protein to adjuvant was proportional to adjuvant concentration. desorption of virus and protein from the adjuvant in substantial, reproducible quantities was achieved by washing adjuvanted preparations with 1.2 m potassium phosphate, followed by dialysis and concentration of wash fluids. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of ...19873033874
hormonal changes in sows after induced porcine parvovirus infection in early pregnancy.hormonal changes, lesions, and virus isolation studies were determined in sows after uterine artery inoculation with porcine parvovirus [( ppv], strain nadl-8) in early pregnancy. two sows were given ppv on days 14 or 16 and were euthanatized and necropsied on day 35 after twice daily plasma collection for hormone measurement. parvovirus was given to 4 sows on day 14 and to 4 sows on day 21 with 5 times daily plasma samples collected for 1 week. sows were examined on days 21 and 28, respectively ...19873035969
clinical, virologic, and histopathologic observations of induced porcine parvovirus infection in boars.twelve 8- to 12-month-old crossbred boars were inoculated with a virulent strain (nadl-8) of porcine parvovirus (ppv). hemicastrations were performed on 6 boars 3, 7, 10, 14, 21, and 28 days after an im injection of 10(8) median cell culture infectious dose (ccid50) of ppv (n = 3) or injection of 10(7.4) ccid50 given intratesticularly (it, n = 3). noninfected cell culture medium (0.25 ml) was injected into each testicle of a 7th boar (it inoculated control). virus or viral antigen was detected i ...19873035971
[restriction analysis of the genome of swine abortion parvovirus and cloning of its psti-ecori fragment].the cultured pig kidney cells infected by the porcine parvovirus (ppv) produced the virions and viral dna. the latter was used as a matrix to synthesize the double stranded dna. the obtained preparation is more homogenic than the natural replicative form and was used for restriction analysis of porcine parvovirus genome and for molecular cloning of its fragment. the isolated recombinant plasmids contained the psti-ecori fragment of ppv dna, containing 70% of the viral genome. the restriction ana ...19873037360
inhibition of porcine parvovirus replication by empty virus particles.the influence of empty porcine parvovirus (ppv) particles on viral replication was examined in cell cultures and in swine. following extensive purification, homogeneous preparations of full and empty ppv preparations were obtained and used for in vitro and in vivo analyses. in the first in vitro experiment, swine testes cells were infected with mixtures of various ratios of empty and full (e/f) particles. the production of both intracellular and extracellular virus was markedly inhibited in the ...19873039947
maternally-derived antibodies to porcine parvovirus and their effect on active antibody production after vaccination with an inactivated oil-emulsion vaccine.two sows which had been vaccinated with an oil-emulsion porcine parvovirus vaccine, and had developed high haemagglutination-inhibiting antibody levels to the virus, farrowed three successive litters each, a total of 74 piglets. serum samples from these piglets were tested for haemagglutination-inhibiting antibody at birth, three and 17 days after birth, and at monthly intervals thereafter to study the decline of maternally-derived antibody. regression curves were constructed from the data to sh ...19873603999
[2 strains of swine parvoviruses isolated from aborted fetuses].two hemagglutinating virus strains were isolated (in primary cell cultures of pig kidneys) from viscera of aborted swine fetuses. a number of serologic, cytologic, physico-chemical, and laboratory investigations with the strains revealed that they belonged to the group of porcine parvovirus (ppv). the isolation of spv from aborted fetuses pointed to the fact that the disease had been widespread among the swine population and plays a part in reproduction disturbances that have come to be known re ...19873617471
cultivation of a pig parvovirus in various cell cultures.the susceptibility of several established cell lines of pig (llc-pk1 = pig kidney; mpk = minipig kidney; pk15 = pig kidney; esk = embryonic swine kidney), bovine (ebtr = embryonic bovine trachea), monkey (ma-104 = fetal rhesus monkey kidney) and human (hel-299 = embryonic human lung) origin to porcine parvovirus was studied. the primary pig kidney cell cultures (ppk) were included in the study as the reference cell system. from the results it appeared that the virus only replicated in cell lines ...19873626887
pathogenicity of a skin isolate of porcine parvovirus in swine fetuses.the pathogenic properties of a skin isolate of porcine parvovirus (ppv), designated kresse isolate, were compared with nadl-8 isolate, a prototype isolate of ppv, by in utero inoculation of mid-term and late-term gestation swine fetuses. fetuses from pregnant sows of mid-gestation were inoculated with either nadl-8 or kresse virus. both isolates were highly pathogenic to mid-gestation fetuses. in contrast, dramatic differences in pathogenicity between these 2 isolates were observed in fetuses in ...19872830705
[isolation of conjugated sera for the immunofluorescence demonstration of swine parvovirus].high-titer, specific serum against porcine parvovirus was obtained via hyperimmunization of rabbits, with the use of a bulgarian isolate that had been partially purified after a known, modified technique. a specific, high-titer conjugate was produced for the immunofluorescence diagnosis of porcine parvoviruses. the microscopic observation of the lamellae of cell cultures, treated with the conjugate, revealed the presence of a specific, typically granulated perinuclear (mostly unilaterally) and, ...19873314114
use of an inactivated vaccine for prevention of parvovirus-induced reproductive failure in gilts.gilts from dams that had been inoculated with inactivated porcine parvovirus (ppv) vaccine before breeding became seronegative to ppv by 26 weeks of age. vaccination of these gilts with inactivated ppv vaccine at 32 weeks of age resulted in an antibody response that peaked at about 2 weeks after vaccination, with -log10 mean hemagglutination inhibiting (hi) antibody titers of less than 2. in the first-year group (82 gilts), hi titers gradually decreased, 20% of the gilts being seronegative by 6 ...19873028999
comparison of porcine parvovirus to other parvoviruses by restriction site mapping and hybridization analysis of southern blots.the genomic relationship between porcine parvovirus (ppv) and several other autonomous parvoviruses was examined by restriction site and hybridization analysis. restriction site maps of the ppv genome were prepared by digesting the double-stranded replicative form of the viral dna with each of eight restriction enzymes. subsequent comparison of such maps with those previously reported for ppv, canine parvovirus (cpv), feline panleukopenia virus (fpv), minute virus of mice (mvm), h-1 virus (h-1) ...19873029312
experience of vaccination against porcine parvovirus in pig-breeding herds: serological status and reproductive performance. 19872841834
antigenic and structural variation of the p28 core polypeptide of goat and sheep retroviruses.the p28 core polypeptides of four isolates of caprine arthritis-encephalitis virus (caev) from goats was compared with those of visna virus (vv) and progressive pneumonia virus (ppv) from sheep. monoclonal antibodies recognized p28 epitopes common to all six retrovirus isolates, a p28 epitope on four caev isolates, but not vv and ppv isolates, a p28 epitope on four caev isolates and vv, but not ppv and a p28 epitope unique to the caev isolate used for immunizing the mouse spleen donor. compariso ...19872440985
porcine parvovirus vaccination. 19882842932
porcine parvovirus vaccination. 19882844016
porcine parvovirus vaccination. 19882845629
detection of antibodies against porcine parvovirus in swine sera by enzyme-linked immunosorbent enzyme-linked immunosorbent assay (elisa) was developed for detection of antibody against porcine parvovirus in swine sera. the antigen used for the assay was partially-purified virus treated with fluorocarbon and shown to contain 7 proteins by sodium dodecylsulfate-polyacrylamide gel electrophoresis. of these proteins 83-, 64- and 60-k proteins reacted in western immunoblotting with swine serum after infection with porcine parvovirus. antibody responses were demonstrated by elisa in pigs sub ...19882845632
mapping of porcine parvovirus dna and development of a diagnostic dna probe.dimeric and monomeric replicative forms of dna of porcine parvovirus (ppv) strain nadl-2 were isolated and examined by restriction enzyme analysis and reciprocal southern blot hybridization during development of a dna probe for ppv. genomic single stranded ppv dna was 5.0 kb long, and results substantiated the rolling-hairpin model of parvovirus dna replication with the primer sequence located in the 3' terminal hairpin loop. an additional finding was the generation of a 4.7 kb species of viral ...19882845634
size and antigenic comparisons among the structural proteins of selected autonomous parvoviruses.the size and antigenic relationships among structural proteins (vps) of canine parvovirus (cpv), feline parvovirus (fpv), porcine parvovirus (ppv), minute virus of mice (mvm) and bovine parvovirus (bpv) were determined by sds-page of radiolabelled, purified virus and immunoprecipitated viral proteins. mature virions of cpv, fpv, ppv and mvm were composed of three vps designated vp1, vp2 and vp3. the corresponding proteins of each virus were similar in molecular weight [79,000 to 82,500 (vp1), 65 ...19883356979
uptake of porcine parvovirus into host and nonhost cells suggests host specificity is determined by intracellular factors.the uptake of porcine parvovirus (ppv) into host cells, permissive or nonpermissive for ppv replication, was monitored by autoradiography, immunofluorescent microscopy, and dual parameter flow cytometry. while both permissive and nonpermissive cells selectively took up the light (activated) form of the virus from a mixed population of heavy and light infectious virions, the virus was only replicated in the permissive cell cultures. transfection of permissive and nonpermissive cells with purified ...19883376550
[experimental studies on maedi-visna].in order to study pathogenicity of sheep lentiviruses, to obtain monospecific sera and to perfect elisa, 3 experiments with different strains were carried out for 4 yr. in expt 1, one clone only of a french maedi-visna strain (564-79) elicits a clear seroconversion in inoculated sheep. in expt 2, k1514 is more immunogenic than k796 and ppv: intratracheal route seems more efficient than intracerebral route. sheep infected by ts mutants (expt 3) are early positive as wild strain k796. nevertheless ...19882838220
field trials of an inactivated, oil-emulsion porcine parvovirus vaccine in british pig herds.inactivated porcine parvovirus vaccines have been available commercially in britain since 1984 and are now widely used in breeding herds. to investigate their value in cost benefit terms an oil-emulsion vaccine developed at weybridge was used in trials on 1243 gilts in 12 herds during the period 1984 to 1986. in each herd approximately half the gilts were given the vaccine before breeding and the remainder were left unvaccinated. blood samples were taken at vaccination and two to four weeks late ...19882839927
porcine parvovirus: replication in and inhibition of selected cellular functions of swine alveolar macrophages and peripheral blood lymphocytes.the ability of four isolates of porcine parvovirus (nadl-8, nadl-2, kbsh, and kresse) to replicate in and affect the functions of swine peripheral blood lymphocytes and alveolar macrophages was studied in vitro. v-strand and c-strand viral dna was present in both concanavalin a- and non-treated lymphocytes as well as alveolar macrophages following infection with all four isolates. indirect fluorescent antibody assays on swine testis cells, inoculated with cell lysates of nadl-8-infected peripher ...19883046562
plaque formation and replication of porcine parvovirus in embryonic swine kidney cell line, esk cells. 19883210492
the ability by different preparations of porcine parvovirus to enhance humoral immunity in swine and guinea pigs.the capacity of different preparations of inactivated porcine parvovirus to stimulate antibody response was studied. the adjuvants chosen were aluminium hydroxide gel [al(oh)3, 30-50%], water-in-mineral-oil emulsion (w/mo, 50%) alone or combined with al(oh)3, and two synthetic products known as dimethyldioctadecylammoniumbromide (dda, 0.16%) and an acrylic acid polymer resin (carbopol 934p, 0.02%) respectively. for each preparation, swine and guinea pigs devoid of antibody to porcine parvovirus ...19883216795
efficacy of an inactivated porcine parvovirus (ppv) vaccine under field conditions. 19883256229
the interferon sensitivity of selected porcine viruses.the objective of this study was to compare the sensitivity of 11 porcine viruses to the antiviral effects of porcine interferon-alpha in serum from piglets which had been infected 19 h previously with transmissible gastroenteritis virus, and of porcine interferon-beta prepared in pk-15 cells by induction with polyinosinic:polycytidylic acid, in yield reduction assays in pig kidney cells which were treated with interferon before virus challenge, and both before and after virus challenge. the most ...19892492445
evaluation and simplification of the world health organization clinical case definition for paediatric aids.the world health organization (who) clinical case definition for paediatric aids was tested during a 1-month period on 221 consecutive hospitalized children in kigali, rwanda. relevant clinical features not included in the who case definition were also evaluated. thirty-four out of the 221 children (15.4%) were hiv seropositive. although the specificity of the who case definition was high (92%), the sensitivity and the positive predictive value (ppv) were low (41 and 48%, respectively). the foll ...19892500955
an enzyme-linked immunosorbent assay for detection of antibodies to porcine enzyme-linked immunosorbent assay (elisa) was developed for detection of antibodies to porcine parvovirus (ppv). antisera to ppv were raised in pigs, for which ppv grown on pk15 cells was used for primary intranasal inoculations, and ppv cultured on autologous kidney cells for booster immunisations. a competition elisa was developed, based on the principle of a double antibody sandwich assay, using immunoglobulin fractions prepared from these sera. the elisa was compared with a haemagglutinat ...19892542351
characterization of a parvovirus isolated from the diarrheic feces of a pig.a small dna virus was isolated from the feces of a sow with diarrhea and identified as a parvovirus on the basis of its properties. the virus replicated preferentially in cell cultures of swine origin, including primary porcine thyroid gland and kidney cell cultures in which the cytopathic effect developed. the virus agglutinated erythrocytes of guinea pig, mouse and human group o but not these of chicken. the growth of the virus was inhibited by 5-iodo-2'-deoxyuridine. the virus was resistant t ...19892544760
in vitro assessment of viral antigen content in inactivated aluminum hydroxide adjuvanted vaccines.antigen capture enzyme immunoassays (elisa) were developed to assess the antigenic content of inactivated aluminum hydroxide (ah) adjuvanted porcine parvovirus, pseudorabies, and infectious bovine rhinotracheitis vaccines. reference preparations of these viruses were constructed as a basis for comparison. because ah-associated elisa interference was largely circumvented, the need for isotopic or complex antigen-adjuvant desorption methods was eliminated. a 4-parameter logistic model related opti ...19892550498
a serological survey of swine parvovirus infection in italy.a serological survey to detect the presence of porcine parvovirus (ppv) infection in italy and its geographic distribution was conducted. 1,332 samples of serum collected in 1983/1984/1985 were taken from pig breeding herds and, to a lesser extent, from fattening piggeries of representative regions of italy. they were tested using the hemagglutination inhibition test (hit). the results of the serological study indicate that parvovirus infection is widespread in italian herds having 70.3% of sera ...19892550741
nucleotide sequence analysis of the capsid genes and the right-hand terminal palindrome of porcine parvovirus, strain nadl-2.the genome of the porcine parvovirus, strain nadl-2, has been cloned and the sequence of map units 28 to 100, which is 3670 bp in length and contains the capsid coding regions and the right-hand terminal palindrome, has been determined. the sequence shows extensive homology with other parvoviruses such as mvm, h-1, cpv, and fpv in the capsid coding region. given the information available from these sequences, the regulatory and capsid coding regions for ppv have been proposed and the amino acid ...19892596019
temperature dependent replication of porcine parvovirus isolates.the replication of four porcine parvovirus isolates, nadl-8, nadl-2, kbsh, and kresse, in swine testes cells were compared at temperatures of 32, 37, and 39 degrees c. replication of the kresse isolate was restricted at 32 and 37 degrees c as evidenced by progeny virus, virus polypeptide and viral dna synthesis, but not at 39 degrees c. in contrast, replication of kbsh was restricted at 39 degrees c, but not at 37 or 32 degrees c. findings from this study support the contention that replication ...19892596974
expression of the plum pox virus coat protein region in escherichia coli.a cdna complementary to the 3' end of plum pox virus (ppv) rna was sequenced. the sequence was investigated for the presumable coat protein cistron by computer-aided translation. a fragment containing the stop codon of the polyprotein gene and a putative virus-specific protease cleavage site was subcloned into an e. coli expression vector. it is shown by immunological analysis that the coat protein cistron is located within the subcloned region.19892655276
artificial cleavage site recognized by plum pox potyvirus protease in escherichia coli.a synthetic plum pox virus (ppv) nib-cp cleavage site was recognized by a ppv protease in an in vivo escherichia coli expression system. the presence of the natural nib-cp cleavage site did not affect processing at the artificial one. however, although both the proteases and the cleavage sites of ppv and tobacco etch virus show high sequence homology, a similar cassette from the tobacco etch virus nib-cp junction was not efficiently recognized by the ppv protease.19892657098
polarized entry of canine parvovirus in an epithelial cell line.the binding and uptake of canine parvovirus (cpv) in polarized epithelial cells were investigated by growing the cells on a permeable support and inoculating with the virus either from the apical or basolateral surface. binding of radiolabeled cpv occurred preferentially on the basolateral surface. in contrast, when a similar experiment was carried out on nonpolarized a72 cells, virus binding occurred regardless of the direction of virus input. binding appeared to be specific for cpv and could n ...19892657102
the complete nucleotide sequence of plum pox virus rna.the complete nucleotide sequence of the rna of an aphid non-transmissible plum pox virus (ppv-nat) isolate has been determined from five overlapping cdna clones. cdna prepared by primer extension was used to determine the 5' terminus. the assembled rna is 9741 nucleotides in length, excluding a 3' terminal poly(a) sequence. one large open reading frame starts at nucleotide positions 36 to 38 and is terminated with an uag codon at positions 9522 to 9524. the putative start codon is located at pos ...19892732699
nucleotide sequence of capsid protein gene of porcine parvovirus.approximately 90% of the genome of porcine parvovirus was cloned into bacterial cells. the nucleotide sequence of the genome from 33 map units (mu) to 95 mu was determined and shown to include the entire gene encoding the capsid proteins. the predicted amino acid sequences of the capsid proteins showed extensive homology to those of other autonomous parvoviruses.19892750278
the complete nucleotide sequence of plum pox potyvirus rna.the complete nucleotide sequence of the plum pox virus (ppv) rna genome has been determined. the rna sequence is 9786 nucleotides in length, excluding the 3'-terminal poly(a) tail. an aug triplet at position 147-149 was assigned as the initiation codon for the translation of the genome size viral polyprotein which would consist of 3140 amino acid residues. the nucleotide sequence of the non-coding regions and the predicted amino acid sequence of the polyprotein of ppv were compared with those pr ...19892773595
porcine parvovirus: dna sequence and genome organization.we have determined the nucleotide sequence of an almost full-length clone of porcine parvovirus (ppv). the sequence is 4973 nucleotides (nt) long. the 3' end of virion dna shows a y-shaped configuration homologous to rodent parvoviruses. the 5' end of virion dna shows a repetition of 127 nt at the carboxy terminus of the capsid proteins. the overall organization of the ppv genome is similar to those of other autonomous parvoviruses. there are two large open reading frames (orfs) that almost enti ...19892794971
the genome-linked protein and 5' end rna sequence of plum pox potyvirus.the infectivity of plum pox potyvirus (ppv) rna was decreased by treatment with proteases. ribonuclease digestion of iodinated ppv rna yielded material which had an electrophoretic mobility corresponding to mr 22,000. this protein presumably corresponds to the protease-sensitive structure needed for infectivity. a protein-linked rnase t1-resistant oligonucleotide, 38 nucleotides long, was sequenced and shown to correspond to the 5' terminus of the rna by sequence comparison to the rnas of two ot ...19892794981
molecular cloning of porcine parvovirus dna for the purpose of obtaining viral antigen synthesis in expression of porcine parvovirus 1.05 kb dna fragment was obtained in escherichia coli under the control both of pr-lambda and lac-promoters. the product of expression under pr-control was demonstrated to show ppv-specific antigenic properties. its electrophoretic mobility corresponded to a molecular weight of approximately 45 kd.19902102651
dot hybridization detection of plum pox virus using 32p-labeled rna probes representing non-structural viral protein genes.a cdna library covering the complete genome of plum pox virus strain d (ppv d) has been obtained, and an endonuclease restriction map derived from it. this map was superposed on the ppv genomic organisation map, established for a nonaphid transmissible strain of ppv (maiss et al., 1989). this allowed us to select seven probes, corresponding to different regions on the ppv genome. these probes were tested in a dot-blot hybridization assay for the detection of ppv. probes of various lengths (0.25 ...19902148174
[the effect of parvovirus vaccination in sows through their 4th parity and the role of influenza h1n1 virus].the effects of vaccination of a porcine parvovirus (ppv) in gilts and the first four litters were studied in a pig-breeding herd. in addition to determination of the technical results, ppv and influenza (h1n1) titres were measured. from the serological findings it was apparent that ppv and influenza (h1n1) virus circulated during the trial. the number of total-born and live-born piglets was significantly higher in the first litter when ppv-vaccinated and non-vaccinated gilts were compared. on th ...19902156355
development of a vaccine preventing parvovirus-induced reproductive failure in inactivated porcine parvovirus (ppv) vaccine for the prevention of ppv-induced reproductive failure in pigs was developed, using virus grown in cell culture, inactivated with beta-propiolactone and adjuvanted with aluminum hydroxide. the vaccine was tested for safety by subcutaneous injection into pregnant gilts. there were no signs of abnormal reactions nor evidence of ppv infection in the gilts or their foetuses when they were sacrificed 6 weeks after vaccination. to demonstrate that the va ...19902165775
persistence of porcine parvovirus in swine infected in utero and followed through maturity.the potential of porcine parvovirus (ppv) to persistently infect swine exposed in utero was studied. forty eight 80- to 95-day-old fetuses from 5 ppv seropositive sows were inoculated intramusculary with a virulent strain of ppv or with cell culture medium (controls). blood samples were collected at birth prior to nursing and at monthly intervals thereafter and tested for antibodies to ppv. virus-inoculated and control pigs were euthanized at either 1 week before birth (-1), at birth (0) and at ...19902166412
establishment of transformed swine fibroblast cell lines using sv40 large t antigen.swine testicle cell lines were established by transformation of primary swine testicle (pst) cells with an sv40 plasmid (psv3-neo), which contains genes conferring resistance to neomycin and expressing sv40 large t antigen. plasmid dna was transfected into pst cells using a lipofection system. two related plasmids, psv2-neo and psv5-neo, failed to induce transformed cells. cells transformed with psv3-neo formed single colonies that were resistant to the antibiotic, g418, and expressed large t an ...19902175590
comparison of commercial kits for the detection of antibody to human immunodeficiency virus type 1 (hiv-1) in nigeria.four commercial kits for the detection of antibodies to hiv-1 were compared with regard to their sensitivity, specificity and positive predictive value. the wellcozyme competitive enzyme immunoassay was the least sensitive (62.5%), while roche eia, was the most sensitive (100%). all the commercial kits gave false negative results except the roche eia system. the serodia particle agglutination test had the least positive predictive value of 26.9% while roche eia had the highest (88.9%). our resul ...19902191859
sensitive enzyme immunoassay for the rapid diagnosis of influenza a virus infections in clinical specimens.samples of nasopharyngeal secretion (nps) from 100 infants and small children admitted for acute respiratory disease during the period from january to march 1989 were examined for the presence of influenza a virus. all samples were tested by enzyme immunoassay (eia), fluorescent antibody (fa) technique and by isolation in cell culture 3-6 h after they were obtained from the patients. of 24 influenza strains found by isolation, 21 were detected by eia and 19 were fa+. in comparison with virus iso ...19902203125
the complete nucleotide sequence of an infectious clone of porcine parvovirus, strain nadl-2.the complete nucleotide sequence of an infectious clone of porcine parvovirus, strain nadl-2, was determined. the nucleotide sequence organization of the viral genome was found to be similar to that of the other autonomous parvoviruses, such as canine parvovirus and minute virus of mice.19902219713
replication of two porcine parvovirus isolates at non-permissive temperatures.previous studies have shown that replication in vitro of the porcine parvovirus (ppv) isolate, kbsh, was restricted at 39 degrees c but not at 37 degrees c. in contrast, replication of the kresse isolate was restricted at 37 degrees c but not at 39 degrees c. in this study, kresse and kbsh isolates were passaged up to ten times in swine testicle (st) cells at non-permissive temperatures, and at subsequent passage viral protein synthesis, viral dna synthesis, and progeny virus were evaluated. kbs ...19902222184
rna helicase: a novel activity associated with a protein encoded by a positive strand rna virus.most positive strand rna viruses infecting plants and animals encode proteins containing the so-called nucleotide binding motif (ntbm) (1) in their amino acid sequences (2). as suggested from the high level of sequence similarity of these viral proteins with the recently described superfamilies of helicase-like proteins (3-5), the ntbm-containing cylindrical inclusion (ci) protein from plum pox virus (ppv), which belongs to the potyvirus group of positive strand rna viruses, is shown to be able ...19902263459
mutational analysis of plum pox potyvirus polyprotein processing by the nia protease in escherichia coli.a binary escherichia coli expression system has been used to study the pathway for proteolytic processing of the plum pox potyvirus (ppv) polyprotein. trans cleavage at the carboxyl end of the cylindrical inclusion protein occurred, although with lower efficiency than that at the large nuclear inclusion protein-capsid protein junction. no trans cleavage at the carboxyl end of the small nuclear inclusion protein (nia) was detected. the proteolytic activities at different cleavage sites of several ...19902273380
porcine parvovirus survey. 19902309430
excretion of porcine parvovirus through the genital tract of boars.the putative binding of porcine parvovirus (ppv) to semen components in vitro was examined along with the shedding pattern of ppv in oronasally infected boars. porcine parvovirus dna was determined to be bound to spermatozoa that had been incubated in vitro with ppv and washed to remove loosely adherent virus. to determine whether ppv was shed in the semen, four 8-month-old boars, seronegative for ppv, were inoculated oronasally with a virulent strain of ppv. prior to virus inoculation, a cathet ...19902316910
infectious in vitro transcripts from a plum pox potyvirus cdna clone.a full-length cdna clone of the 9786 nt plum pox virus (ppv) rna genome has been cloned downstream from a phage t7 rna polymerase promoter. the rnas synthesized by in vitro run-off transcription in the presence of the 5' cap analog m7gpppg were infectious in nicotiana clevelandii plants. no infectivity was detected when the transcriptions were carried out in the absence of the cap analog. inoculations of the local lesion host chenopodium foetidum indicated that the infectivity of the synthetic t ...19902371774
construction of an infectious genomic clone of porcine parvovirus: effect of the 5'-end on dna replication.the linear single-stranded dna genome of the porcine parvovirus, an autonomous parvovirus, was cloned in duplex form into the bacterial plasmid puc18 using a simple and reliable method. these clones were stable during propagation in escherichia coli jm109. the recombinant clones of porcine parvovirus were infectious when transfected into monolayers of swine testes cells as identified by the development of cytopathic effect, indirect immunofluorescence with specific antiserum, and hemagglutinatio ...19902371779
multiplication of attenuated and virulent porcine parvoviruses in colostrum-deprived, neonatal pigs.colostrum-deprived, neonatal, 2 days old pigs were inoculated with the attenuated ht-/sk or the virulent 90hs strain of porcine parvovirus (ppv) by the oral or subcutaneous route and sacrificed 2, 4 or 6 days after inoculation. then, comparison was made on viral multiplication in pigs between the two strains. pigs inoculated with the ht-/sk strain showed no detectable viremia or hi antibody responses against ppv within 6 days after inoculation. only in pigs inoculated by the subcutaneous route, ...19901962832
detection of porcine parvovirus using nonradioactive nucleic acid hybridization.nonradioactive slot blot hybridization assays were established for the detection of porcine parvovirus (ppv), using either a digoxigenin-labeled dna probe or a biotinylated rna probe. all probes were prepared from a 3.3-kb pst1-ecor1 dna fragment of the nadl8 isolate of ppv. the sensitivity and specificity of the probes in a slot blot system were evaluated in comparison with a 32p-radiolabeled rna probe. using an anti-digoxigenin alkaline phosphatase detection system, at least 1 ng of viral repl ...19901965580
development of hybridization probes on the basis of recombinant dna to identify porcine parvoviruses and rotaviruses.porcine parvovirus (ppv) and porcine rotavirus (prv) infections can be diagnosed, and the diagnosis greatly contributes to their control. for the diagnosis of ppv and prv of pigs recombinant dna were obtained which could be used as hybridization probes. homology between ppv-rna and cloned cdna was confirmed, and the ability of plasmid probes to detect prv was demonstrated. hybridization with preparations of both ppv-infected cells and purified ppv gave positive reproducible results. the results ...19901966361
in vitro exposure of preimplantation porcine embryos to porcine parvovirus.early porcine embryos at the four- to eight-cell stage can be infected with either the virulent (nadl-8) or avirulent kbsh strain of porcine parvovirus (ppv) by microinjection or by incubation of embryos with virus. treatment of embryos by microinjection of virus or incubation in media with virus did not significantly inhibit in vitro development of the embryos when compared with untreated controls. rna-dna hybridization was used to identify the presence of virus associated with embryos. it was ...199016726750
proteolytic activity of plum pox virus-tobacco etch virus chimeric nia proteases.plasmids encoding chimeric nia-type proteases made of sequences from the potyviruses plum pox virus (ppv) and tobacco etch virus (tev) have been constructed. their proteolytic activity on the large nuclear inclusion protein (nib)-capsid protein (cp) junction of each virus was assayed in escherichia coli cells. the amino half of the protease seemed to be involved neither in the enzymatic catalysis nor in substrate recognition. in spite of the large homology among the ppv and tev nia-type protease ...19912015911
plum pox potyvirus rna replication in a crude membrane fraction from infected nicotiana clevelandii vitro synthesis of plum pox potyvirus (ppv)-specific nucleic acid has been measured in a crude fraction prepared from leaves of ppv-infected nicotiana clevelandii plants. using alkali and dnase treatments, the synthesized nucleic acid was shown to be rna. the electrophoretic mobility and the differing sensitivity to rnase at high and low salt concentrations allowed the identification of in vitro products probably corresponding to replicative form and replicative intermediate rna, as well as t ...19912016593
comparison of two rapid methods for detection of respiratory syncytial virus (rsv) (testpack rsv and ortho rsv elisa) with direct immunofluorescence and virus isolation for the diagnosis of pediatric rsv infection.the ability of two commercial immunoassays to detect respiratory syncytial virus (rsv) in respiratory specimens was evaluated as follows: 152 specimens were tested by testpack rsv (abbott), and 72 were tested by ortho rsv elisa (ortho). test outcomes were compared with those of virus isolation alone, direct immunofluorescence assay (dfa) alone, or virus isolation and/or dfa. testpack rsv versus virus isolation showed 91% sensitivity, 96% specificity, 93% positive predictive value (ppv), and 95% ...19912037684
a current assessment of the role of porcine parvovirus as a cause of fetal porcine hundred one litters containing 1 or more dead porcine fetuses were collected at an iowa abattoir during a 2-month interval and examined for evidence of viral infection. each of 1,137 fetuses (302 dead, 835 alive) of these litters was tested for porcine parvovirus (ppv) antigens by direct immunofluorescence microscopy (fa) of fetal lung. antigens of ppv were detected in the lungs of most of the fetuses of 11 of the litters. the 11 fa-positive litters contained 105 dead (100 fa-positive) and 1 ...19911645596
experimental in utero infection of pig foetuses with porcine parvovirus (ppv).pig foetuses of various gestational ages were exposed to experimental infection with porcine parvovirus (ppv) in utero. inoculation of 40-, 50- and 60-day-old foetuses with ppv caused foetal death and mummification and spread of the infection to non-inoculated foetuses. inoculation at 80 and 100 days gestation caused pathological lesions of various degrees whereas spread of infection occurred only sporadically. serological examinations of foetuses of different ages suggest that immunocompetence ...19911653481
catalytic antisense rnas produced by incorporating ribozyme cassettes into cdna.a simple strategy is described for the generation of catalytic hammerhead-type ribozymes (rz) that can be used as highly specific endoribonucleases to cleave a particular target rna. the technique requires that a cloned cdna fragment is available which encodes at least a part of the target rna. about 25 different restriction recognition sequences can be utilized to incorporate specifically designed dna cassettes into the cdna. besides some nucleotides which are specific for a certain restriction ...19911660835
outbreaks in quebec pig farms of respiratory and reproductive problems associated with encephalomyocarditis virus.encephalomyocarditis virus (emcv) was isolated from tissues of aborted fetuses and weaned and suckling piglets from 4 different pig farms in quebec. the farms were experiencing reproductive failure in sows of different parities concomitant to respiratory problems in suckling and postweaning piglets. at necropsy, gross lesions were confined to the lung and consisted of pulmonary congestion and edema of various degrees. lesions of multifocal interstitial to proliferative pneumonia were found in th ...19911662074
outbreaks of porcine parvovirus disease in panama.the first recorded isolation of porcine parvovirus (ppv) in panama is described. the outbreaks of ppv disease were characterised by a high prevalence of mummified foetuses, stillborn and weak pigs and a common source of exposure. diagnosis was based on virus isolation and by demonstrating viral antigen in lungs of affected foetuses. six farms in four different provinces were involved. rapid control of the epizootic was achieved through the use of an inactivated ppv vaccine in the affected farms.19911662424
molecular biology of the viral haemorrhagic disease virus of rabbits.viral haemorrhagic disease virus (vhdv) of rabbits is a small, nonenveloped dna virus which contains a linear, single-stranded genome approximately 7,000 bases in length. the virions are icosahedral in symmetry, consisting of 180 subunits with pentamer-hexamer clustering. the capsid is composed of four structural polypeptides: vp1:60-61 kda, vp2:54.7 kda, vp3:52 kda, and vp4:26-28 kda. vp1 is a major structural polypeptide which constitutes approximately 54.7% of the total viral proteins. there ...19911760580
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