detection of challenge virus in fetal tissues by nested pcr as a test of the potency of a porcine parvovirus 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
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
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
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
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
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 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
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
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
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
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 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
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
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
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
intranasal delivery of recombinant parvovirus-like particles elicits cytotoxic t-cell and neutralizing antibody responses.we previously demonstrated that chimeric porcine parvovirus-like particles (ppv:vlp) carrying heterologous epitopes, when injected intraperitoneally into mice without adjuvant, activate strong cd4(+) and cd8(+) t-cell responses specific for the foreign epitopes. in the present study, we investigated the immunogenicity of ppv:vlp carrying a cd8(+) t-cell epitope from the lymphocytic choriomeningitis virus (lcmv) administered by mucosal routes. mice immunized intranasally with recombinant ppv:vlp, ...199910074120
use of parvovirus-like particles for vaccination and induction of multiple immune responses.expression of the vp2 gene of autonomous parvoviruses in insect cells with the use of the baculovirus system has led to the production of virus-like particles (vlps) formed by the self-assembly of vp2. these vlps are expressed at high levels and can easily be purified by salt fractionation. they are highly immunogenic in the corresponding host, being fully protective at doses as low as 1-2 microg of purified material per animal. no special adjuvants are required. an interesting property of these ...199910075910
reproductive tract infections in primary healthcare, family planning, and dermatovenereology clinics: evaluation of syndromic management in 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
[comparative investigations of a combined vaccine against parvovirus and erysipelas and corresponding monovaccines in different vaccination schedules. 1: field trial].in a field trial, the development of antibodies of a combined vaccine against the porcine parvovirus (ppv) as well as against swine erysipelas was compared with corresponding mono vaccines. furthermore, these vaccines were used in different vaccination schedules. the tests were carried out on 109 gilts in three closed farms. in all gilts, a basic immunization repeated twice was carried out at the age of six months and at intervals of three weeks. the revaccination was carried out four months aft ...199910384706
new methods for inactivation of lipid-enveloped and non-enveloped viruses.two new methods are described for inactivating lipid-enveloped and non-enveloped viruses in plasma-derived products such as coagulation factors and intravenous immunoglobulin (igiv). iodine/sephadex delivers iodine to igiv solutions in a slow, controlled way and allows for inactivation of > or = 4 logs of porcine parvovirus (ppv), a hardy non-enveloped virus, under conditions which do not measurably damage the structural or functional properties of the igiv, and with essentially no iodination of ...19989873761
reproduction of lesions of postweaning multisystemic wasting syndrome by infection of conventional pigs with porcine circovirus type 2 alone or in combination with porcine multisystemic wasting syndrome (pmws) has recently emerged as an important disease of pigs in north america, europe and asia. porcine circovirus type 2 (pcv2) and porcine parvovirus (ppv) have been isolated from affected pigs. to investigate the pathogenicity of these isolates, groups of colostrum-deprived conventional pigs were inoculated with pcv2 alone (n=4), ppv alone (n=3) or dually with pcv2 and ppv (n=7) and examined post mortem between 21 and 26 days post-infection (dpi). tw ...200010627387
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
removal of viruses from human intravenous immune globulin by 35 nm nanofiltration.viral safety is an important prerequisite for clinical immunoglobulin preparations. a common manufacturing practice is to utilize several virus removal/inactivation process steps to ensure the safety of human intravenous immunoglobulin (ivig). in this regard, we examined the use of planova 35 nm filters to reduce potential loads of both non-enveloped and enveloped viruses prior to end-stage solvent detergent treatment. the nanofiltration process was validated for removal of a variety of envelope ...199810403036
monoclonal antibodies to the gp5 of porcine reproductive and respiratory syndrome virus are more effective in virus neutralization than monoclonal antibodies to the gp4.the arterivirus porcine reproductive and respiratory syndrome virus (prrsv) contains six structural proteins the roles of which are not completely understood. in a preceding study, immunization with the dutch isolate i10 of prrsv had led to the development of mabs against four structural proteins [wieczorek-krohmer, m., 1994. herstellung und charakterisierung von monoklonalen antikörpern gegen das virus des porzinen reproduktiven und respiratorischen syndroms (prrsv). inaugural-dissertation, lud ...199910227120
engineering parvovirus-like particles for the induction of b-cell, cd4(+) and ctl antigen delivery system based on hybrid recombinant parvovirus-like particles (vlps) formed by the self-assembly of the capsid vp2 protein of porcine (ppv) or canine parvovirus (cpv) expressed in insect cells with the baculovirus system has been developed. ppv:vlps containing a cd8(+) epitope from the lcmv nucleoprotein evoked a potent ctl response and were able to protect mice against a lethal infection with the virus. also, ppv:vlps containing the c3:t epitope from poliovirus elicited a cd4 ...199910506659
detection of porcine parvovirus dna by the polymerase chain reaction assay using primers to the highly conserved nonstructural protein gene, ns-1.porcine parvovirus (ppv) infection is associated with reproductive losses in swine and its causative agent, the ppv, has been isolated worldwide. serological surveys and virus isolation studies throughout brazil confirm the occurrence of ppv infection in this country. the most common methods to detect ppv infection are fluorescent antibody staining of fetal tissues, hemagglutination assay of tissue extracts and virus isolation from fetal tissues. non-specificity and low sensitivity are the major ...199910204709
molecular and structural basis of the evolution of parvovirus tropism.parvoviruses have small genomes and, consequently, are highly dependent on their host for various functions in their reproduction. since these viruses generally use ubiquitous receptors, restrictions are usually intracellularly regulated. a lack of mitosis, and hence absence of enzymes required for dna replication, is a powerful block of virus infection. allotropic determinants have been identified for several parvoviruses: porcine parvovirus, canine parvovirus (cpv), feline parvovirus (feline p ...199910497831
the effect of porcine parvovirus and porcine reproductive and respiratory syndrome virus on porcine reproductive performance.from a worldwide perspective, porcine parvovirus (ppv) and porcine reproductive and respiratory syndrome virus (prrsv) are the most common viral causes of porcine reproductive failure. a typical epidemic of ppv-induced reproductive failure is presented as an increased number of mummified fetuses and sometimes, entire litters are mummified. if infection with ppv is very early in gestation, the number of liveborn pigs may be further reduced as a result of embryonic death and resorption. during the ...200010844195
in vivo induction of a high-avidity, high-frequency cytotoxic t-lymphocyte response is associated with antiviral protective immunity.many approaches are currently being developed to deliver exogenous antigen into the major histocompatibility complex class i-restricted antigen pathway, leading to in vivo priming of cd8(+) cytotoxic t cells. one attractive possibility consists of targeting the antigen to phagocytic or macropinocytic antigen-presenting cells. in this study, we demonstrate that strong cd8(+) class i-restricted cytotoxic responses are induced upon intraperitoneal immunization of mice with different peptides, chara ...200010846055
comparative analysis of dna flow cytometry and cytology of bladder washings: review of discordant cases.dna analysis is becoming an important diagnostic and prognostic adjunct test in urinary cytology. the aim of this study was to compare the results of dna flow cytometry (fcm) with the cytologic diagnosis of bladder washings (bw). dna ploidy was evaluated in 251 bw. in 65 cases, follow-up surgical biopsies were available. cytology results were classified as positive and negative, and fcm results were categorized as diploid and aneuploid. both tests were evaluated independently. cases were defined ...200010649514
coinfection by porcine circoviruses and porcine parvovirus in pigs with naturally acquired postweaning multisystemic wasting syndrome.postweaning multisystemic wasting syndrome (pmws) is an emerging disease in swine. recently, the disease has been reproduced with inocula containing a newly described porcine circovirus (pcv), designated pcv 2, and porcine parvovirus (ppv). in order to determine if these viruses interact in naturally acquired pmws, affected tissues from field cases were examined by immunohistochemistry (ihc) and polymerase chain reaction (pcr) for pcv 2 and ppv, as well as by pcr for the other recognized porcine ...200010690771
experimental transmission of porcine circovirus type 2 (pcv2) in weaned pigs: a sequential study.weaned specific pathogen-free pigs were inoculated intranasally with porcine circovirus type 2 (pcv2) and killed in groups of two or three animals at 6, 13, 20, 27 and 34 days post-inoculation (dpi), together with appropriate uninfected controls, for examination by histopathological, immunohistochemical (immunogold silver staining; igss), polymerase chain reaction (pcr) and viral isolation techniques. serum samples were also collected for detection of antibodies. no major clinical signs were obs ...200011041995
virus safety of avital bone tissue transplants: evaluation of sterilization steps of spongiosa cuboids using a peracetic acid-methanol mixture.the aim of this study was to validate the virus-inactivating/eliminating capacity of the manufacturing process of spongiosa cuboids. both the sterilization step with peracetic acid (paa)/ethanol and the defatting step of bones with chloroform/methanol (2:1, v/v) were investigated. relevant enveloped, non-enveloped, and model viruses belonging to different virus families were included in the investigation: human immunodeficiency virus type 2 (hiv-2), hepatitis a virus (hav), poliovirus (pv-1), ps ...199910652175
parapoxviruses: potential alternative vectors for directing the immune response in permissive and non-permissive hosts.parapoxvirus (ppv) represents a genus of the poxviridae, and particularly ppv ovis (orf virus, ov) seems to offer several potential advantages for the use of vector vaccine. therefore, we started to investigate the genome of the highly attenuated ov strain d1701, which was only poorly characterised until now. due to recombination of non-homologous sequences, part of the right hand end of the d1701 genome was duplicated and translocated to the opposite end of the genome. as a consequence gene del ...199910486932
porcine circoviruses: a review.porcine circoviruses (pcv) are small nonenveloped dna viruses containing a unique single-stranded circular genome. previously, no recognized link was found between pcv infection of pigs and disease, and pcv was considered a nonpathogenic agent. over the last 5 years, a "novel" pcv, designated pcv2, has been associated with various disease syndromes in pigs, primarily postweaning multisystemic wasting syndrome (pmws). pigs with pmws have a variety of clinical signs, including debility, dyspnea, p ...200010690769
investigation of porcine parvovirus among persons with hemophilia receiving hyate:c porcine factor viii concentrate.porcine clotting factor has been used for more than 15 years to treat severe bleeding episodes in persons with hemophilia who have antibodies to human clotting factor. in 1996, qc procedures revealed for the first time the presence of porcine parvovirus (ppv) in the product. this report describes an investigation to determine the extent of product contamination and to evaluate past recipients of porcine clotting factor (hyate:c, speywood biopharm) for evidence of ppv infection.200010864993
generation of recombinant parapoxviruses: non-essential genes suitable for insertion and expression of foreign genes.orf virus (ov) is an epitheliotropic poxvirus and belongs to the genus parapoxvirus (ppv). ppv, especially ov, is regarded as a promising candidate for an expression vector. among available live vaccines only strain d1701 represents a highly attenuated ov strain with clearly reduced pathogenicity. therefore, we started to identify potentially non-essential genes or regions of d1701, which might be suitable for insertion and expression of foreign genes. the present contribution reviews some of th ...200011000469
biotechnological aspects of plum pox virus.plum pox potyvirus (ppv), the causal agent of a devastating disease that affects stone fruit trees, is becoming a target of intense studies intended both to fight against viral infection and to develop practical applications based on the current knowledge of potyvirus molecular biology. this review focuses on biotechnological aspects related to ppv, such as novel diagnostic techniques that facilitate detection and typing of virus isolates, strategies to implement pathogen-derived resistance thro ...200010656327
distribution of porcine parvovirus in porcine circovirus 2-infected pigs with postweaning multisystemic wasting syndrome as shown by in-situ hybridization with a nonradioactive digoxigenin-labelled probe was used to study the distribution of porcine parvovirus (ppv) in formalin-fixed paraffin wax-embedded tissues from 10 porcine circovirus 2 (pcv2)-infected weaned pigs with naturally occurring postweaning multisystemic wasting syndrome (pmws). a 226 base pair dna fragment from a vp2 structural gene was generated by polymerase chain reaction (pcr) and used as a probe. lymph node, spleen, thymus and tonsil were positive by pcr, ...200011042001
preservation of 5'-end integrity of a potyvirus genomic rna is not dependent on template specificity.full-length in vitro transcripts of plum pox potyvirus (ppv) genomic rna with mutations altering the number of 5'-terminal adenosine residues were able to infect nicotiana clevelandii plants, whereas a mutant with a substitution of adenosine in position 2 by guanosine failed to infect. the genomic 5' end was template-independently repaired during in vivo rna synthesis producing wild-type viral progeny. putative models of replication initiation are discussed.200010753716
sensitivity, specificity, and positive predictive value of oral opportunistic infections in adults with hiv/aids as markers of immune suppression and viral burden.the purpose of this study was to assess the use of human immunodeficiency virus (hiv)-related oral opportunistic infections as markers of immune suppression and viral burden in adults with hiv/acquired immunodeficiency syndrome (aids).200010936837
identification of a pathogenicity determinant of plum pox virus in the sequence encoding the c-terminal region of protein p3+6k(1).a full-length genomic cdna clone of a plum pox potyvirus (ppv) isolate belonging to the m strain (ppv-ps) has been cloned downstream from a bacteriophage t7 polymerase promoter and sequenced. transcripts from the resulting plasmid, pgppvps, were infectious and, in herbaceous hosts, produced symptoms that differed from those of virus progeny of pgppv, a full-length genomic cdna clone of the d strain ppv-r. viable ppv-r/-ps chimeric viruses were constructed by recombination of the cdna clones in v ...200010675393
native electrophoresis and western blot analysis (neweb): a method for characterization of different forms of potyvirus particles and similar nucleoprotein complexes in extracts of infected plant tissues.a combination of native electrophoresis and immunodetection (western blot) was used for the characterization of nucleoprotein particles of the potyvirus plum pox virus (ppv). virus particles were electrophoresed directly from plant extracts in agarose or mixed acrylamide-agarose gels under native conditions, blotted on nitrocellulose membranes, and characterized with the aid of a coat protein-specific antibody. using this combined methodology, called neweb (native electrophoresis and western blo ...200010950988
mutations in the coat protein gene of plum pox virus suppress particle assembly, heterologous encapsidation and complementation in transgenic plants of nicotiana benthamiana.two different motifs in the coat protein (cp) of plum pox virus (ppv) (r(3015)q(3016), d(3059)) were mutated by replacing the respective amino acids with others possessing different chemical properties. the mutated cp genes were introduced into an infectious full-length clone of ppv (p35ppv-nat) to investigate their influence on systemic infection of transgenic wild-type ppv cp-expressing and non-transgenic plants of nicotiana benthamiana. all mutants failed to establish systemic infections in n ...200010675394
the use of transgenic fruit trees as a resistance strategy for virus epidemics: the plum pox (sharka) model.sharka or plum pox, caused by plum pox virus (ppv: genus potyvirus; family potyviridae), is the most serious disease of prunus. most cultivated prunus species are highly susceptible and conventional breeding has not produced highly resistant and commercially acceptable varieties. success in developing virus-resistant herbaceous crops through genetic engineering led us to investigate this approach for resistance to ppv. our programme aims to develop a biotechnological approach to ppv control that ...200011137162
trial-of-antibiotic algorithm for the diagnosis of tuberculosis in a district hospital in a developing country with high hiv evaluate a diagnostic algorithm for pulmonary tuberculosis based on smear microscopy and objective response to trial of antibiotics.200010864181
simultaneous detection of porcine circovirus type 2 and porcine parvovirus in pigs with pmws by multiplex pcr. 200111570792
experimental reproduction of severe wasting disease by co-infection of pigs with porcine circovirus and porcine parvovirus.colostrum-deprived pigs were infected intranasally with a recent isolate of porcine circovirus (pcv2) and a porcine parvovirus (ppv), both from canadian pigs with post-weaning multisystemic wasting syndrome (pmws). four pigs were inoculated with pcv2 alone, three with ppv alone, five with a combined pcv2/ppv inoculum, and two with a chloroform-treated combined pcv2/ppv inoculum. pigs were killed 21-26 days after infection and tissue samples examined for gross and microscopical lesions and for th ...199910373289
protection of rabbits against rabbit hemorrhagic disease virus by immunization with the vp60 protein expressed in plants with a potyvirus-based vector.a new plum pox potyvirus (ppv)-based vector has been constructed for the expression of full-length individual foreign proteins. the foreign sequences are cloned between the nib replicase and capsid protein (cp) cistrons. the heterologous protein is split from the rest of the potyviral polyprotein by cleavage at the site that originally separated the nib and cp proteins and at an additional nia protease recognition site engineered at its amino-terminal end. this vector (ppv-nk) has been used to c ...200111162842
effect of different baculovirus inactivation procedures on the integrity and immunogenicity of porcine parvovirus-like particles.we have demonstrated earlier the usefulness of recombinant porcine parvovirus (ppv) virus-like particles (vlps) as an efficient recombinant vaccine for ppv. here, we have demonstrated that preparations of ppv vlps could be contaminated by recombinant baculoviruses. since these baculoviruses can be a problem for the registration and safety requirements of the recombinant vaccine, we have tested different baculovirus inactivation strategies, studying simultaneously the integrity and immunogenicity ...200011115693
transgenic or plant expression vector-mediated recombination of plum pox virus.different mutants of an infectious full-length clone (p35ppv-nat) of plum pox virus (ppv) were constructed: three mutants with mutations of the assembly motifs rq and df in the coat protein gene (cp) and two cp chimeras with exchanges in the cp core region of zucchini yellow mosaic virus and potato virus y. the assembly mutants were restricted to single infected cells, whereas the ppv chimeras were able to produce systemic infections in nicotiana benthamiana plants. after passages in different t ...200010906199
preparation of diagnostic monoclonal antibodies against two potyviruses.diagnostic monoclonal and polyclonal antibodies against bean yellow mosaic virus (bymv) and plum pox virus (ppv) were prepared, characterized and used for detection of these viruses in infected plants by enzyme-linked immunosorbent assay (elisa), immunoblot analysis and tissue print immunoblot assay (tpiba).199910749372
plum pox virus capsid protein mobility in sds-polyacrylamide gel electrophoresis.slovak plum pox virus (ppv) isolates bor-3 and kr-4 behaved atypically in polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (sds-page) of their capsid proteins (cps). whereas other tested ppv isolates could be sorted by sds-page into groups corresponding to the m or d strains, as controlled by restriction fragment length polymorphism (rflp) analysis, the two above mentioned isolates behaved as the m strain according to rflp analysis but not sds-page. slight mobility di ...199910749373
dynamics of porcine circovirus type 2 infection in a herd of pigs with postweaning multisystemic wasting determine the pattern of infection for porcine circovirus type 2 (pcv2) in a herd of pigs with postweaning multisystemic wasting syndrome (pmws).200211911570
parapoxviruses: from the lesion to the viral genome.viruses of the genus parapoxvirus from the family poxviridae cause widespread but localized diseases of small and large ruminants. the economically most important disease is contagious pustular dermatitis or contagious ecthyma among sheep and goats, often simply called orf. the parapoxviruses (ppv) can be transmitted to man leading to localized lesions that are named pseudocowpox or milkers' node as being mostly restricted to the hands and fingers. in cattle two forms of ppv manifestation are co ...200211911596
identification of an n-terminal domain of the plum pox potyvirus ci rna helicase involved in self-interaction in a yeast two-hybrid system.potyvirus ci rna helicase is a protein involved in rna genome replication and virus movement. the protein aggregates in the cytoplasm of infected cells to form typical cylindrical inclusions. a yeast two-hybrid system was used to analyse interactions of the ci rna helicase from plum pox potyvirus (ppv) with itself and with other viral proteins. no interactions could be detected of full-length ci protein with itself or with ppv p3/6k1, nia, nib or cp proteins. however, positive self-interactions ...200111172111
detection of human cytomegalovirus pp67 late gene transcripts in cerebrospinal fluid of human immunodeficiency virus type 1-infected patients by nucleic acid sequence-based amplification.this study examined the clinical correlation between the presence of human cytomegalovirus (hcmv) pp67 mrna in cerebrospinal fluid (csf) and active hcmv central nervous system (cns) disease in patients with human immunodeficiency virus type 1 (hiv-1). in total, 76 csf specimens collected from 65 hiv-1-positive patients diagnosed with hcmv cns disease, other non-hcmv-related cns diseases, or no cns disease were tested for the presence of hcmv pp67 mrna using the nuclisens cytomegalovirus (cmv) pp ...200010790122
evaluation and validation of virus removal by ultrafiltration during the production of diaspirin crosslinked haemoglobin (dclhb).virus retention during ultrafiltration through a/g technology filter cartridges was investigated to characterize the removal process and validate the degree of virus titre reduction during the filtration of red blood cell haemolysates performed as part of the production of diaspirin crosslinked haemoglobin (dclhb). when viruses were suspended in phosphate buffered saline solution, retention was greater with larger sized viruses and smaller filter pore size. virus titre was maintained at starting ...200010885615
a sequential study of experimental infection of pigs with porcine circovirus and porcine parvovirus: immunostaining of cryostat sections and virus isolation.the sequential tissue distribution of virus was investigated using virus isolation and immunofluorescence tests in 1-day-old piglets inoculated with porcine circovirus 2 (pcv2) and/or porcine parvovirus (ppv). enlarged mesenteric lymph nodes were seen in the pig inoculated with pcv2 alone and killed at 26 days post-inoculation (pi). one of the pigs inoculated with pcv2 and ppv and killed at 21 days pi had an enlarged liver. the pig killed at 26 days pi in this group had enlarged liver, kidneys a ...200010763376
simultaneous detection of porcine circovirus 2 and porcine parvovirus in naturally and experimentally coinfected pigs by double in situ hybridization.a technique for double in situ hybridization to simultaneously detect porcine circovirus 2 (pcv2) and porcine parvovirus (ppv) in the same tissue section was developed and applied to lymph node and spleen from 8 pigs experimentally coinfected with pcv2 and ppv and 20 pigs with naturally occurring postweaning multisystemic wasting syndrome. for double labeling studies, the tissue samples were processed sequentially, first for ppv in situ hybridization using a digoxigenin-labeled probe and then fo ...200212033680
infectious agents identified in pigs with multifocal interstitial nephritis at kidney was taken from each of 100 pigs at slaughter; 50 had gross lesions of multifocal interstitial nephritis and 50 had no gross lesions. forty-nine of the affected kidneys had lesions that were characterised by the presence of either a few randomly distributed or numerous widely disseminated pale foci, 1 to 3 mm in diameter, on the cortical surface (white-dotted kidneys). microscopically, these focal inflammatory lesions often had a distinct lymphofollicular pattern (follicular nephritis) ...200211871667
efficiency of inoculation of peach gf305 seedlings with plum pox virus by different methods.peach gf305 is frequently used as rootstock in experiments to evaluate the resistance of different species of prunus to plum pox virus (ppv) because of its extreme susceptibility. however, transmission of ppv in prunus species is sometimes problematic due to its low concentration or uneven distribution in these species. to determine the most effective way of transmitting the virus, different infection methods (by aphids, grafting, mechanical infection and injection) were tested using dideron ppv ...200011332275
detection of porcine enteroviruses by nrt-pcr: differentiation of cpe groups i-iii with specific primer sets.porcine enteroviruses (pev) comprising at least 13 serotypes grouped into three species are described as causative agents of neurological disorders, fertility disorders, and dermal lesions of swine. despite their well-documented acid stability, enteric infection route, and similarity of clinical symptoms, most of the porcine enterovirus (pev) serotypes are set apart from the genus enterovirus of the picornaviridae. hence, pcr procedures used commonly to detect enteroviruses are not applicable to ...200010960708
pilot study of expedited hiv-1 testing of women in labor at an inner-city hospital in new york evaluate the feasibility of offering voluntary counseling and expedited human immunodeficiency virus (hiv) testing to women in labor, and to assess the characteristics of two rapid hiv assays compared with results from an expedited standard enzyme immunoassay (eia), with western blot confirmation, as indicated, we undertook a pilot study immediately prior to enactment of new york state regulations (august 1999) requiring expedited testing of laboring women (or newborns) with undocumented hiv ...200111321245
localization of plum pox virus in stem and petiole tissues of apricot cultivars by immuno-tissue printing.localization of plum pox virus (ppv) in stem and petiole tissues of four susceptible and four resistant apricot cultivars has been studied. consecutive 1-mm spaced transverse sections were taken from the tissues and were printed onto nitrocellulose membrane in duplicate. for virus-specific detection, one series of prints was probed with an antibody to ppv coat and the density of stains was evaluated by light microscopy. another series of prints was treated with a substrate but not with the antib ...200011332274
clinical and pathological observations on pigs with postweaning multisystemic wasting syndrome.the aim of this work was to characterise the lesions and agents present in clinically normal and clinically affected pigs on a farm during an outbreak of postweaning multisystemic wasting syndrome (pmws), and to evaluate the diagnostic techniques for detecting porcine circovirus type 2 (pcv-2) and other microorganisms. four pigs in the early stage and 11 pigs in the late stage of the disease, and eight clinically normal pigs were necropsied. samples of lymphoid tissue and serum were also obtaine ...200111594382
combined pap smear, cervicography and hpv dna testing in the detection of cervical intraepithelial neoplasia and cancer.the sensitivity of the pap smear (pap) continues to be the subject of debate. during the past several years, cervicography (cer) and hpv dna testing have been suggested as optional tools in the screening of cervical cancer precursors.200010833984
viral wasting syndrome of swine: experimental reproduction of postweaning multisystemic wasting syndrome in gnotobiotic swine by coinfection with porcine circovirus 2 and porcine gnotobiotic piglets were inoculated intranasally with in vitro passaged porcine circovirus 1 (pcv-1), pcv-2, and porcine parvovirus (ppv) alone or in combination (pcv-1/pcv-2, pcv-1/ppv, and pcv-2/ppv). piglets were evaluated for 1) the development of porcine postweaning multisystemic wasting syndrome (pmws), 2) distribution of viral antigens by immunochemistry, and 3) viremia and the presence of viral dna in nasal and ocular secretions and feces. all single agent-infected piglets an ...200010810990
virological response to interferon therapy of chronic hepatitis b as measured by a highly sensitive the interferon (ifn) treatment of chronic hepatitis b, there is no accepted definition of virological response as measured by highly sensitive hbv dna assays. in the present study of 98 patients given ifn (10 mu/day for 1 week, then 10 mu tiw for 11 weeks) with or without prednisolone priming, a virological response was identified as log hbv dna/ml below 6.0 (by amplicor monitor, roche) 6 months post-treatment. at this time, 92% (33/36) of the sustained responders (sr) still had detectable vi ...200111555192
occupational risk of infection by varicella zoster virus in belgian healthcare workers: a seroprevalence assess the prevalence of varicella zoster virus (vzv) antibodies in flemish (belgian) healthcare workers, to investigate the association between seronegativity and selected variables, and to assess the reliability of recall about disease as a predictor of immunity.200010935943
post-transcriptional gene silencing in plum pox virus resistant transgenic european plum containing the plum pox potyvirus coat protein gene.transgenic plums containing the plum pox potyvirus coat protein (ppv-cp) gene were inoculated with ppv. infection was monitored by evaluating symptoms, elisa, and ic-rt-pcr. transgenic clone c5 was highly resistant to ppv during four years of testing and displayed characteristics typical of post-transcriptional gene silencing (ptgs), including a high level of transgene transcription in the nucleus, low levels of transgene mrna in the cytoplasm, a complex multicopy transgene insertion with aberra ...200111437277
clinical diagnosis of influenza virus infection: evaluation of diagnostic tools in general practice.with the development of new antiviral agents for influenza, the urge for rapid and reliable diagnosis of influenza becomes increasingly important. respiratory virus infections are difficult to distinguish on clinical grounds. general practitioners (gps) however, still depend on their clinical judgement.200111510391
pathogenicity determinants in the complex virus population of a plum pox virus isolate.several subisolates were separated from a single plum pox virus (ppv) isolate, ppv-ps. in spite of an extremely high sequence conservation (more than 99.9% similarity), different subisolates differed largely in pathogenicity in herbaceous hosts and infectivity in woody plants. the severity of symptomatology did not seem to correlate with virus accumulation. sequence analysis and site-directed mutagenesis demonstrated that single amino acid changes in the helper component (hc) protein caused a dr ...200111277425
integrated rt-pcr/nested pcr diagnosis for differentiating between subgroups of plum pox rt-pcr/nested pcr technique was developed for the simultaneous detection and typing of plum pox virus (ppv) and its major types--dideron (d), marcus (m), el-amar (ea) and cherry (c). degenerated oligonucleotides were synthesized for the general detection of ppv, flanking the coding sequence for the n-terminal portion of the coat protein (cp), within which strain-specific differences were identified. on the basis of these characteristic differences, degenerated primer pairs were designed to di ...200111226563
response of antioxidative enzymes to plum pox virus in two apricot cultivars.recent evidence has indicated that activated oxygen species (aos) may function as molecular signals in the induction of defence genes. in the present work, the response of antioxidative enzymes to the plum pox virus (ppv) was examined in two apricot (prunus armeniaca l.) cultivars, which behaved differently against ppv infection. in the inoculated resistant cultivar (goldrich), a decrease in catalase (cat) as well as an increase in total superoxide dismutase (sod) and dehydroascorbate reductase ...200111240915
budding of fowlpox and pigeonpox viruses at the surface of infected cells.chick embryo fibroblasts and chorioallantoic membranes infected with fowlpox virus (fwpv) or pigeonpox virus (ppv) were examined by transmission and scanning electron microscopy. immature virus particles were observed in finely granular areas, i.e. virus factories, of the cytoplasm. these particles had various forms depending on their stages of development. many tubular structures were also seen in these regions. mature virus particles with ellipsoidal or brick-shaped forms enclosing electron-de ...200111347712
episomal expression of a hammerhead ribozyme directed against plum pox virus.two related antisense rnas directed against plum pox virus (ppv) were expressed episomally in nicotiana clevelandii by infection with recombinant potato virus x (pvx). one recombinant pvx expressed an ordinary ppv antisense rna of about 400 nucleotides, while the other expressed a related antisense rna that carried the catalytic domain of a hammerhead ribozyme. inoculation with the latter recombinant pvx resulted in the accumulation of ribozyme rna that was catalytically active when tested in vi ...200010930659
experimental reproduction of severe disease in cd/cd pigs concurrently infected with type 2 porcine circovirus and porcine reproductive and respiratory syndrome virus.three-week-old cesarean-derived colostrum-deprived (cd/cd) pigs were inoculated with porcine circovirus type 2 (pcv2, n = 19), porcine reproductive and respiratory syndrome virus (prrsv, n = 13), concurrent pcv2 and prrsv (pcv2/prrsv, n = 17), or a sham inoculum (n = 12) to compare the independent and combined effects of these agents. necropsies were performed at 7, 10, 14, 21, 35, and 49 days postinoculation (dpi) or when pigs became moribund. by 10 dpi, pcv2/prrsv-inoculated pigs had severe dy ...200111572560
porcine factor viii: current status and future developments.high-purity porcine factor viii (pfviii) (hyate:c, ipsen, uk), with a specific activity of > 125 u mg(-1) protein, has been shown to be effective in up to 90% of bleeds in patients with fviii inhibitors. these inhibitors have been shown to have a median 15% cross-reactivity to pfviii, and even less cross-reactivity in patients with acquired haemophilia. its use is sometimes associated with a transient fall in platelet count and with transfusion reactions. furthermore, it is not virally attenuate ...200211882080
host-specific involvement of the hc protein in the long-distance movement of potyviruses.plum pox virus (ppv) is a member of the potyvirus genus that, in nature, infects trees of the prunus genus. although ppv infects systemically several species of the nicotiana genus, such as n. clevelandii and n. benthamiana, and replicates in the inoculated leaves of n. tabacum, it is unable to infect systemically the last host. the long-distance movement defect of ppv was corrected in transgenic tobacco plants expressing the 5"-terminal region of the genome of tobacco etch virus (tev), a potyvi ...200211799187
process for the preparation of pathogen-inactivated rbc concentrates by using pen110 chemistry: preclinical studies.a pathogen-inactivation process for rbc concentrates is being developed by using pen110 chemistry (inactine, v.i. technologies). the objective of this study was to characterize the quality of rbcs prepared by using the pen110 process and to measure the virucidal effect achieved against two viruses.200211896326
molecular variability of the p3-6k1 genomic region among geographically and biologically distinct isolates of plum pox evaluate molecular variability in the 5' region of the plum pox virus (ppv) genome, a fragment spanning the c-terminal part of p3, the complete 6k1 and start of the ci gene in 12 slovak and french ppv isolates was amplified in ic-rt-pcr and sequenced. computer analysis of obtained and previously published sequences showed rather substantial differences among isolates of ppv-m and d subgroups (percentage of nucleotide identity ranged from 85.65 to 87.68%). there was a relatively low percentage ...200211958455
modified indirect porcine circovirus (pcv) type 2-based and recombinant capsid protein (orf2)-based enzyme-linked immunosorbent assays for detection of antibodies to pcv.postweaning multisystemic wasting syndrome of swine associated with porcine circovirus (pcv) is a recently reported and economically important disease. simple and reliable diagnostic methods are needed for detecting antibodies to pcv type 2 (pcv2) for monitoring of pcv infection. here, we report the development of two modified indirect enzyme-linked immunosorbent assays (elisas): a pcv2 elisa based on cell-culture-propagated pcv2 and an orf2 elisa based on recombinant major capsid protein. pcv2 ...200211777826
a viral phospholipase a2 is required for parvovirus infectivity.sequence analysis revealed phospholipase a2 (pla2) motifs in capsid proteins of parvoviruses. although pla2 activity is not known to exist in viruses, putative pla2s from divergent parvoviruses, human b19, porcine parvovirus, and insect gmdnv (densovirus from galleria mellonella), can emulate catalytic properties of secreted pla2. mutations of critical amino acids strongly reduce both pla2 activity and, proportionally, viral infectivity, but cell surface attachment, entry, and endocytosis by pla ...200111702787
persistent parapoxvirus infection in cattle.the possibility of persistent parapoxvirus (ppv) infection was investigated by serologically and genetically using cattle infected with the virus experimentally and naturally. three cattle were inoculated with the virus subcutaneously at several spots in the lips and abdominal regions. small papules developed in the inoculated regions, and antibodies to the virus developed and continued persistently. one animal, from which one ppv had been previously isolated, was also subjected to serological a ...200212061631
the capsid protein of a plant single-stranded rna virus is modified by o-linked n-acetylglucosamine.plum pox virus (ppv) is a member of the potyvirus genus of plant viruses. labeling with udp-[3h]galactose and galactosyltransferase indicated that the capsid protein (cp) of ppv is a glycoprotein with n-acetylglucosamine terminal residues. mass spectrometry analysis of different ppv isolates and mutants revealed o-linked n-acetylglucosamination, a modification barely studied in plant proteins, of serine and/or threonine residues near the amino end of ppv cp. cp of ppv virions is also modified by ...200211606576
the structure of porcine parvovirus: comparison with related viruses.the structure of baculovirus-expressed porcine parvovirus (ppv) capsids was solved using x-ray crystallography and was found to be similar to the related canine parvovirus (cpv) and minute virus of mice (mvm). the ppv capsid protein has 57 % and 49 % amino acid sequence identity with cpv and mvm, respectively, but the degree of conservation of surface-exposed residues is lower than average. consequently, most of the structural differences are on the surface and are the probable cause of the know ...200211827486
experimental infection of colostrum deprived piglets with porcine circovirus 2 (pcv2) and porcine reproductive and respiratory syndrome virus (prrsv) potentiates pcv2 replication.experimental infection of colostrum-deprived (cd) pigs with a combined inoculum of porcine circovirus 2 (pcv2) and porcine reproductive and respiratory syndrome virus (prrsv) potentiated the replication and distribution of pcv2 virus, when compared with pigs inoculated with pcv2 alone. the replication and distribution of prrsv in dually infected pigs was not enhanced, when compared to pigs inoculated with prrsv alone. the mechanisms involved in the potentiation of pcv2 replication in pcv2/prrsv ...200011205128
virus safety of a porcine-derived medical device: evaluation of a viral inactivation method.the goal of this study was to evaluate the efficacy of a virus-inactivating process for use during the preparation of porcine-derived extracellular matrix biomaterials for human clinical implantation. porcine small intestine, the source material for the tissue-engineered, small intestinal submucosa (sis) biomaterial, was evaluated. relevant enveloped, non-enveloped, and model viruses representative of different virus families were included in the investigation: porcine parvovirus (ppv), porcine ...200212115437
how successfully do general practitioners diagnose herpetic gingivo-stomatitis clinically?herpetic gingivo-stomatitis is a common, often painful affliction of young children. recently, aciclovir treatment has been found to be effective in hospital-referred cases, an approach limited in general practice where laboratory diagnosis is invariably impractical. this study demonstrated that 49 out of 63 clinical diagnoses of herpetic gingivo-stomatitis [ppv = 78%] made by 27 gps were subsequently validated by laboratory virus culture. this suggests that herpetic gingivo-stomatitis might be ...200212051213
large scale production and downstream processing of a recombinant porcine parvovirus vaccine.porcine parvovirus (ppv) virus-like particles (vlps) constitute a potential vaccine for prevention of parvovirus-induced reproductive failure in gilts. here we report the development of a large scale (25 l) production process for ppv-vlps with baculovirus-infected insect cells. a low multiplicity of infection (moi) strategy was efficiently applied avoiding the use of an extra baculovirus expansion step. the optimal harvest time was defined at 120 h post-infection at the moi used, with the cell c ...200212073130
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