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low temperature and pressure stability of picornaviruses: implications for virus uncoating.the family picornaviridae includes several viruses of great economic and medical importance. poliovirus replicates in the human digestive tract, causing disease that may range in severity from a mild infection to a fatal paralysis. the human rhinovirus is the most important etiologic agent of the common cold in adults and children. foot-and-mouth disease virus (fmdv) causes one of the most economically important diseases in cattle. these viruses have in common a capsid structure composed of 60 c ...199910049311
flexibility of the major antigenic loop of foot-and-mouth disease virus bound to a fab fragment of a neutralising antibody: structure and neutralisation.the interaction of foot-and-mouth disease virus (fmdv) serotype c (clone c-s8c1) with a strongly neutralising monoclonal antibody (mab) 4c4 has been studied by combining data from cryoelectron microscopy and x-ray crystallography. the mab 4c4 binds to the exposed flexible gh-loop of viral protein 1 (vp1), which appears to retain its flexibility, allowing movement of the bound fab. this is in striking contrast to mab sd6, which binds to the same gh-loop of vp1 but exhibits no movement of the boun ...199910069951
induction of a protective antibody response to foot and mouth disease virus in mice following oral or parenteral immunization with alfalfa transgenic plants expressing the viral structural protein vp1.the utilization of transgenic plants expressing recombinant antigens to be used in the formulation of experimental immunogens has been recently communicated. we report here the development of transgenic plants of alfalfa expressing the structural protein vp1 of foot and mouth disease virus (fmdv). the presence of the transgenes in the plants was confirmed by pcr and their specific transcription was demonstrated by rt-pcr. mice parenterally immunized using leaf extracts or receiving in their diet ...199910069960
noncytopathic flavivirus replicon rna-based system for expression and delivery of heterologous genes.noncytopathic replicons of the flavivirus kunjin (kun) were employed for expression and delivery of heterologous genes. replicon vector c20dx2arep, containing a unique cloning site followed by the sequence of 2a autoprotease of foot-and-mouth disease virus, was constructed and used for expression of a number of heterologous genes including chloramphenicol acetyltransferase (cat), green fluorescent protein (gfp), beta-galactosidase, glycoprotein g of vesicular stomatitis virus, and the core and n ...199910069962
[synthesis and immunogenic properties of peptides--fragments of the immunodominant regions of the vp1 protein of the asia-1 type of foot- and-mouth disease virus].potential immunodominant epitopes were predicted on the basis of a theoretical analysis of the antigenic structure of the vp1 protein of the type asia-1 foot-and-mouth disease virus. peptides corresponding to the 140-153, 136-153, 132-153, 143-157, 137-157, and 193-208 fragments of the vp1 protein sequence were synthesized by the solid phase method, and the immunogenic properties of the peptides were studied on guinea pigs. the shortest peptide exhibiting the protective effect was found to corre ...199810079947
differentiating infection from vaccination in foot-and-mouth disease using a panel of recombinant, non-structural proteins in elisa.a profiling elisa was developed to detect antibody to the non-structural (ns) proteins lb, 2c, 3a, 3d, and the polyprotein 3abc, of foot-and-mouth disease virus (fmdv). the assay was used to examine panels of sera from naive cattle, and from experimentally infected or vaccinated animals. all sera from cattle experimentally infected with any of the seven serotypes of fmdv were positive for antibody to 2c, 3a, 3d and 3abc, and the majority were positive for lb. the three categories of sera could b ...19989491499
the foot and mouth disease virus type o outbreak of 1992 is not related to vaccine strain (o/r2/75).vaccination is the only pragmatic approach to control foot and mouth disease in india. strict quality control measures are essential to supply potent vaccine to the field application, in addition to monitoring the performance of the vaccine in the field. during the process of monitoring, an outbreak of fmd in vaccinated animals caused by type "o" virus in tanjavur district of tamil nadu and a type "o" virus from unvaccinated herd of karnataka were studied. field isolates and vaccine virus were s ...19989608661
vp1-coding sequences of recent isolates of foot-and-mouth disease virus types a, o and asia1.a large part of the capsid protein vp1-coding sequence of foot-and-mouth disease virus, isolated between 1993 and 1996 in europe, was amplified by the reverse transcription-dependent polymerase chain reaction (rt-pcr). the same was done with some non-european virus isolates, especially those against which vaccines were currently produced. the products were sequenced, and the sequences aligned. the alignment comprises sequences of the types a, o and asia 1. although the provenance of virus introd ...19989608664
[molecular basis of changes in biological properties of foot and mouth disease virus of subtype a22].primary structure of capsid proteins and rna polymerase of three closely related strains of foot and mouth disease virus (fmdv), subtype a22, differing by biological properties (the initial epitheliotropic strain a22 550 and its derivatives: thermoresistant myotropic a22 550/4 and thermosensitive attenuated a22 645) are compared by nucleic acid sequencing and analysis of the amino acid sequencing. the study revealed 1 substitute in vpi and 8 in rna polymerase in the myotropic variant and 1 subst ...19989611758
mutational analysis of discontinuous epitopes of foot-and-mouth disease virus using an unprocessed capsid protomer precursor.an unprocessed capsid precursor (p1) of foot-and-mouth disease virus (fmdv) has been expressed in mammalian cells to study discontinuous epitopes involved in viral neutralization. amino acid replacements found in virus-escape mutants were engineered in the p1 precursor by site-directed mutagenesis of the plasmid. in all cases the replacements abolished recognition of unprocessed p1 by the relevant monoclonal antibodies (mabs), paralleling the effects of the corresponding substitutions in neutral ...19989617767
detection and characterization of foot-and-mouth disease virus in sub-saharan africa.genomic amplification of the vp1 gene of sat-type foot-and-mouth disease virus (fmdv) was performed with published and novel oligonucleotide primers. the primer pair with the highest sat-type recognition (67%) was identified and selected for optimization. modifications to primers significantly improved sat-type detection (100%), broadened the recognition range to european (a, o and c) and asian (asia-1) serotypes and improved test sensitivity. in addition to being able to confirm the presence of ...19989629589
infection with foot-and-mouth disease virus results in a rapid reduction of mhc class i surface expression.the modulation of mhc class i molecule expression on the surface of cells as a consequence of foot-and-mouth disease virus (fmdv) infection has been examined. on cells infected with fmdv, class i expression was reduced to approximately 70% of the initial value 3 h after the infection and to 53% after 6 h. on cells depleted of surface class i complexes by acid treatment, the appearance of newly assembled class i-peptide complexes on the cell surface of non-infected cells increased immediately upo ...19989519820
antigenic structure of foot and mouth disease virus type a22 (indian isolates).variations in foot and mouth disease virus are due to amino acid substitutions in the vp1, which is a major immunogen. analysis of this hypervariable region is essential to know the antigenic structure of the serotype and is necessary to select a suitable vaccine strain. fmdv type a22 is one of the four prevailing virus types for which the vaccine is used regularly. to understand the antigenic structure of this type, carboxy- terminal region of vp1 from two field isolates and vaccine virus were ...19989536655
characterizing sequence variation in the vp1 capsid proteins of foot and mouth disease virus (serotype 0) with respect to virion structure.the vp1 capsid protein of foot and mouth disease virus (fmdv) is highly polymorphic and contains several of the major immunogenic sites important to effective antibody neutralization and subsequent viral clearance by the immune system. whether this high level of polymorphism is of adaptive value to the virus remains unknown. in this study we examined sequence data from a set of 55 isolates in order to establish the nature of selective pressures acting on this gene. using the known molecular stru ...19989541542
analysis of the b and t cell response in guinea pigs induced with recombinant vaccinia expressing foot-and-mouth disease virus structural proteins.recombinant vaccinia viruses expressing foot-and-mouth disease virus (fmdv) p1 and vp1 genes have been used to study the immune response induced by these viral polypeptides in guinea pigs. anti-fmdv antibodies, but not neutralizing activity, were detected in the sera from immunized animals. the results indicate that both cd4+ and cd8+ fmdv-specific t cells were induced by the vaccinia recombinants. consistently with the activation of cd4+ t cells, lymphocytes from immunized animals specifically ...19989541622
the potential of retro-inverso peptides as synthetic vaccines.retro-inverso (ri) peptides, also called all-d-retro peptides, have been shown to mimic the antigenic and immunogenic properties of l-peptides successfully. ri peptides corresponding to the loop 141-159 of the vp1 protein of foot-and-mouth disease virus (fmdv) have been synthesized and used to immunize rabbits and guinea pigs. these peptides induced longer-lasting and higher antibody titres in immunized animals than did the corresponding l-peptides and the antibodies cross-reacted strongly with ...19989554267
foot-and-mouth disease virus virulent for cattle utilizes the integrin alpha(v)beta3 as its receptor.adsorption and plaque formation of foot-and-mouth disease virus (fmdv) serotype a12 are inhibited by antibodies to the integrin alpha(v)beta3 (a. berinstein et al., j. virol. 69:2664-2666, 1995). a human cell line, k562, which does not normally express alpha(v)beta3 cannot replicate this serotype unless cells are transfected with cdnas encoding this integrin (k562-alpha(v)beta3 cells). in contrast, we found that a tissue culture-propagated fmdv, type o1bfs, was able to replicate in nontransfecte ...19989557639
antibody response in mice inoculated with dna expressing foot-and-mouth disease virus capsid proteins.candidate foot-and-mouth disease (fmd) dna vaccines designed to produce viral capsids lacking infectious viral nucleic acid were evaluated. plasmid dnas containing a portion of the fmdv genome coding for the capsid precursor protein (p1-2a) and wild-type or mutant viral proteinase 3c (plasmids p12x3c or p12x3c-mut, respectively) were constructed. cell-free translation reactions programmed with pp12x3c (wild-type 3c) and pp12x3c-mut produced a capsid precursor, but only the reactions programmed w ...19989557740
study of the immunogenicity of different recombinant mengo viruses expressing hiv1 and siv epitopes.recombinant mengo viruses expressing heterologous genes have proven to be safe and immunogenic in both mice and primates, and to be able to induce both humoral and cellular immune responses (altmeyer et al., 1995, 1996). several recombinant mengo viruses expressing either a large region (aa 65-206) of the hiv1 nef gene product, or cytotoxic t lymphocyte (ctl) epitopic regions from the siv gag (aa 182-190), nef (aa 155-178) and pol (aa 587-601) gene products were engineered. the heterologous anti ...19989561560
emergency vaccination of pigs against foot-and-mouth disease: protection against disease and reduction in contact transmission.the protective ability of two novel oil-based fmd vaccines in pigs was examined. both vaccine formulations were shown to protect pigs against airborne challenge with homologous fmdv within four days of vaccination, but not at two and three days post-vaccination. protection was associated with the induction of variable and low titre serum antibody responses. a transmission study showed that protective immunisation resulted in reduced virus excretion. vaccination at seven days, but not at four day ...19989562696
evolution of a common structural core in the internal ribosome entry sites of picornavirus.the translational control involving internal ribosome binding occurs in poliovirus (pv), human rhinoviruses (hrv), encephalomyocarditis virus (emcv), foot-and-mouth disease virus (fmdv), and hepatitis a virus (hav). internal ribosome binding utilizes cis-acting genetic elements of approximately 450 nucleotides (nt) termed the internal ribosome entry sites (ires) found in these picornaviral 5'-untranslated region (5'utr). although these ires elements are quite different in their primary sequence, ...19989562889
homologous and heterologous antibody response of cattle and sheep after vaccination with foot and mouth disease and influenza viruses.homologous and heterologous antibody response to fmd and influenza vaccines was studied in 37 calves and 45 lambs at the age of 2 months. the fmd and influenza monovalent killed vaccines were administered simultaneously twice. another group of 18 calves was vaccinated twice, first at the age of 2 months and second at the age of 6 months, with trivalent fmd vaccine. the antibody titers were measured by elisa and hi after second vaccination, for fmdv and influenza, respectively. the conclusions of ...19989569464
induction of anti foot and mouth disease virus t and b cell responses in cattle immunized with a peptide representing ten amino acids of vp1.we previously demonstrated that the immunization of cattle with a synthetic peptide representing the amino acid sequence of foot and mouth disease virus (fmdv) type o1 campos vp1 residues 135-160 (p135-160), containing immunodominant t and b epitopes, was able to induce a strong neutralizing antibody (na) response. the epitope mapping of p135-160 identified t and b epitopes in the area restricted to amino acid residues 135-144 (zamorano et al. 1994, virology 201; 1995, virology 212). we are now ...19989569465
inhibition of foot and mouth disease virus (fmdv) uncoating by a plant-derived peptide isolated from melia azedarach l leaves.meliacine (ma), a peptide isolated from leaves of the high plant melia azedarach l inhibited the multiplication of foot and mouth disease virus (fmdv) in bhk-21 cells. in this report, we establish that the ma-inhibitable process takes place within the first hour of the viral reproductive cycle. ma had no virucidal effect and did not affect adsorption and penetration of the virus in cells. in experiments with neutral red-labeled virus, it was found that ma significantly suppressed the development ...19989572558
recognition of picornavirus internal ribosome entry sites within cells; influence of cellular and viral proteins.the ability of different picornavirus internal ribosome entry site (ires) elements to direct initiation of protein synthesis has been assayed in different cell lines in the presence and absence of viral proteases that inhibit cap-dependent protein synthesis. reporter plasmids that express dicistronic mrnas, containing different ires elements, with the general structure cat/ires/luc, have been assayed. in each plasmid, the cat sequence encodes chloramphenicol acetyl transferase and the luc sequen ...19989582094
[physico-chemical bases of the mechanism of thermal inactivation of the foot-and-mouth disease virus].experiments demonstrated that the effect of water activity on the solvate complex of virions underlies the mechanism of thermal inactivation of the foot and mouth disease virus in suspension; changes in the structure of the complex impair the electrophysical balance of the rna-protein relations and hence, destroy the virus. heating of virus-containing suspensions at moderate positive temperatures leads to destruction of the noninfectious part of virus population of 146s particles, thus decreasin ...19989606878
host factors affecting the homologous and heterologous immune response of cattle to fmdv: genetic background, age, virus strains and route of administration.sixty bulls were tested for antibodies to the heterologous serotype c1 of fmdv following repeatable vaccinations with a commercial trivalent vaccine (o1, a22, asia1). six (10%) bulls were found to possess rather high levels of heterologous neutralizing antibodies which showed accumulative trend with age. two high positive and two negative bulls for the heterologous serotype c1 were selected for progeny test involving ten daughters of each bull. the four bulls, either positive or negative for the ...19989607052
a universal virus inactivant for decontaminating blood and biopharmaceutical products.removal of virus infectivity from blood and biopharmaceutical products prepared from blood is an issue of considerable importance. for biopharmaceutical products, removal can usually be achieved by a series of fractionation steps or by inactivation with a suitable reagent. irrespective of the methods that are chosen it is vital that the biological activity of the product is not impaired. for blood and unfractionated plasma or serum, the problem is even more challenging. selective inactivation of ...19989637748
antibody to the nonstructural proteins of foot-and-mouth disease virus in vaccinated animals exposed to infection.cattle which have been infected with foot-and-mouth disease (fmd) virus can be differentiated from those that have been vaccinated on the basis of the detection of antibody to one or more of the non-structural (ns) proteins of the virus. cattle which have been protected by vaccination can become persistently infected with fmd virus (fmdv) without ever showing clinical signs. vaccinated, protected cattle which are persistently infected cannot be distinguished from animals that merely have been va ...19989652054
differentiating foot-and-mouth disease virus-infected from vaccinated animals with baculovirus-expressed specific proteins.we had shown in preliminary studies with a small number of animals that antibodies against 2c could be detected in cattle and pigs which had been infected with fmdv but not in animals which had been vaccinated against the disease. to determine whether this test was generally applicable, sera from several hundred animals which had been vaccinated with different products in many countries have been tested in an elisa using baculovirus expressed 2c. our results show that only 1-2% of the sera gave ...19989652055
cattle response to foot-and-mouth disease virus nonstructural proteins as antigens within vaccines produced using different concentrations.four groups of ten nine-month-old nelore heifers were used for this study. each group received one of four foot-and-mouth disease (fmd) trivalent vaccines for the duration of the experiment. the four vaccine formulations (normal, 2x, 4x and 8x) differed in 140s content to determine the serological reactivities to fmd virus (fmdv) nonstructural proteins 2c, 3abc and 3d. vaccination was by the intramuscular administration of vaccine on day 0, 180 and 360. bleedings were done at 30 days post vaccin ...19989652056
diagnostic potential of mab-based elisas for antibodies to non-structural proteins of foot-and-mouth disease virus to differentiate infection from vaccination.this paper summarises the development of monoclonal antibody (mab)-based immunoassays measuring antibodies to non-structural proteins of fmdv to differentiate infection from vaccination. of the three non-structural proteins 2c, 3c and 3abc evaluated in this study, the polypeptide 3abc was the most immunogenic. three elisas for the detection of antibodies to 3abc were developed. two assays rely on the competition of test sera against either a anti-3a mab or against antisera to 3abc raised in rabb ...19989652058
detection of cattle exposed to foot-and-mouth disease virus by means of an indirect elisa test using bioengineered nonstructural polyprotein 3abc. 19989652059
rt-pcr in foot-and-mouth disease diagnosis.a rt-pcr assay for the specific detection of rna sequences from foot-and-mouth disease virus (fmdv) has been developed. the procedure permits also the detection of sequences that correlate with established fmdv serotypes. a computer program that allows selection of genotype-specific primers for rt-pcr amplification was used for the identification of fmdv specific sequences for pcr amplification on rna replicase (3d) gene regions. specific, rapid and highly sensitive detection was achieved for a ...19989652064
detection of foot-and-mouth disease by reverse transcription polymerase chain reaction and virus isolation in contact sheep without clinical signs of foot-and-mouth disease.two non-vaccinated sheep were experimentally infected with fmdv and one day later 4 other sheep were brought in contact. although the contact sheep showed no clinical signs, serology indicated that all sheep became infected. various secretion samples, taken over a period of at least one month, and various tissue samples were examined for the presence of fmdv by rt-pcr and by virus isolation. fmdv was most often found in saliva (mouth swabs), followed by nasal secretion and sera. faecal material, ...19989652065
influence of il-12 on interferon-gamma production by bovine leucocyte subsets in response to bovine respiratory syncytial virus.the cytokine il-12 is a key molecule in the regulation of cd4+ t cell development and specifically potentiates the development of t helper 1 responses in mouse and man. however the biological effects mediated by bovine il-12 have not been defined in cattle. to produce the expression of the two mature proteins a polyprotein approach was used. this system is employed by positive strand viruses and encodes both products from a single open reading frame (orf). the 2a region of foot-and-mouth disease ...19989656442
multiple virulence determinants of foot-and-mouth disease virus in cell culture.hypervirulent variants of foot-and-mouth disease virus (fmdv) of serotype c arise upon serial cytolytic or persistent infections in cell culture. a specific mutation in the internal ribosome entry site of persistent fmdv was previously associated with enhanced translation initiation activity that could contribute to the hypervirulent phenotype for bhk-21 cells. here we report that several hypervirulent fmdv variants arising upon serial cytolytic passage show an invariant internal ribosome entry ...19989658076
monoclonal antibodies, against o1 serotype foot-and-mouth disease virus, from a natural bovine host, recognize similar antigenic features to those defined by the mouse.eight neutralizing and two non-neutralizing anti-foot-and-mouth disease virus (fmdv) bovine igg1 and igg2 monoclonal antibodies (bmabs) recognize conformationally dependent epitopes. the majority of those shown to neutralize virus passively protected mice from virus challenge, regardless of isotype. well-characterized anti-fmdv mouse mabs, representing five independent neutralizing epitopes on o1 serotype virus, were examined with each of the ten bmabs in a competition-based elisa. five of the n ...19989680132
in vivo analysis of the stability and fitness of variants recovered from foot-and-mouth disease virus quasispecies.we have analysed the ability to infect pigs of two foot-and-mouth disease virus (fmdv) variants isolated at low frequencies from virus populations (quasispecies) generated in pigs on infection with a parental virus, c-s8c1. a monoclonal antibody-resistant mutant (marm21), and a variant isolated at early times post-infection (s-3t1), each exhibiting a unique amino acid substitution in vp1, were able to cause disease in pigs, both by direct inoculation or by contact transmission. the symptoms deve ...19989680133
the biological relevance of virus neutralisation sites for virulence and vaccine protection in the guinea pig model of foot-and-mouth disease.five neutralisation epitopes have been defined for the o1 kaufbeuren strain of foot-and-mouth disease virus (fmdv) by neutralising murine monoclonal antibodies (mabs). a mutant virus which is resistant to all these mabs also resists neutralisation by bovine polyclonal sera, and this characteristic was exploited in the current study to investigate the biological relevance of neutralisation sites in fmdv virulence and vaccine protection. the five site neutralisation-resistant mutant was shown to b ...19989683571
biosensor characterization of antigenic site a of foot-and-mouth disease virus presented in different vector systems.the region 141-160 of the vp1 protein of foot-and-mouth disease virus known as site a is an immunodominant region that has been extensively studied for the purpose of developing a synthetic vaccine. in the present study, site a of foot-and-mouth disease virus was inserted in three different loops of the maltose-binding protein and its antigenicity was compared with site a presented as a conjugated synthetic peptide or inserted in beta-galactosidase. the affinity of antibodies elicited against th ...19989684999
a rt-pcr assay for the differential diagnosis of vesicular viral diseases of swine.a rt-pcr assay based on specific amplification of rna sequences from each of the etiological agents of three important vesicular diseases that affect swine, foot-and-mouth disease virus (fmdv), swine vesicular disease virus (svdv), and vesicular stomatitis virus (vsv), was developed. genotype-specific primers that amplified dna fragments of differential size from svdv 3d gene or vsv l gene were selected with the aid of a computer program. experimental testing of the primers predicted as svdv-spe ...19989694330
quantitation of foot-and-mouth disease virus genomes in bovine tissue by competitive rt-pcr.the sensitivity of a reverse transcription-dependent polymerase chain reaction (rt-pcr) for detecting foot-and-mouth disease virus (fmdv) genomes was quantified by use of rna transcribed in vitro from fmdv-specific cdna. previously, the cdna had been elongated by 228 base pairs. the minimum number of template molecules required to obtain the specific rt-pcr product was determined to be 10(4). this was achieved by use of 1 microg of primer for cdna synthesis and by undertaking of at least 30 cycl ...19989694331
protection of swine by live and inactivated vaccines prepared from a leader proteinase-deficient serotype a12 foot-and-mouth disease virus.previously, we demonstrated that a genetically engineered variant of foot-and-mouth disease virus (fmdv) serotype a12 lacking the leader proteinase-coding region (a12-llv2) was attenuated and induced an immune response that partially protected cattle from fmd. in this study, a12-llv2 was tested in swine as a live or chemically inactivated vaccine. animals vaccinated with chemically inactivated a12-llv2 or wild-type (wt) virus in oil adjuvant developed high levels of neutralizing antibodies and w ...19989711798
construction and evaluation of an attenuated vaccine for foot-and-mouth disease: difficulty adapting the leader proteinase-deleted strategy to the serotype o1 virus.over the last few years we have utilized a system to genetically engineer foot-and-mouth disease virus (fmdv) to produce live-attenuated vaccine candidates. these candidates have been generated in the genetic background of a tissue culture-adapted strain of serotype a12 virus. based on this a12 system, we created a virus lacking the sequence encoding the leader (l) proteinase (piccone et al., 1995), and demonstrated that this leaderless virus, a12-llv2 was avirulent in bovine and swine, and coul ...19989712511
modulation of the antigen presentation activity in foot and mouth disease virus (fmdv) vaccines by two adjuvants: avridine and a water soluble fraction of mycobacterium sp.we have previously demonstrated that the presence of the antigen presenting cells (apc) is critical in the induction and maintenance of the immune response in animals infected or immunized with inactivated fmdv. the use of immunological adjuvants has been repeatedly shown to be essential for the improvement of the immunogenicity in fmdv vaccines. specifically, we have previously shown that the addition of the synthetic lipoamide avridine (avr) or a water soluble fraction of mycobacterium sp. (ws ...19989713938
d-peptides as immunogens and diagnostic reagents.there has been a regain of interest in the immunological applications of peptides assembled partly or totally from d-amino acids. such peptides are much more stable to proteolysis than natural l-peptides and they have considerable potential as synthetic vaccines and as immunomodulators in t-cell responses. retro-inverso, also called retro-all-d or retroenantio, peptide analogues that closely mimic the structure of protein antigens are obtained by assembling amino acid residues in the reverse ord ...19989720264
genetic heterogeneity of indian field isolates of foot-and-mouth disease virus serotype o as revealed by partial sequencing of 1d gene.the sequence of 165 nucleotides at the 3' end of the 1d gene, determined from rt pcr amplified cdna fragments, of 25 type o strains isolated from different parts/regions of india during 1987 1995 and the vaccine strain (r2/75) currently in use in india were subjected to phylogenetic analysis. one isolate from the neighbouring country nepal was also included in the study. the virus/ field strains showed high degree of genetic heterogeneity among themselves with % divergence in nucleotide sequence ...19989725665
problems with bhk 21 cells.the properties of baby hamster kidney (bhk 21) cells are modified by passage in suspension culture. the suspended cells differ from monolayer cells in the surface expression of some integrin chains involved in attachment of foot-and-mouth disease virus (fmdv), in particular the progressive down-regulation of both alpha5 and alphav integrin chains. this down-regulation is correlated with the loss of actin stress fibres. fmdv particles from these cells are unstable towards the aziridine used in in ...19989737382
differentiation of infection from vaccination in foot-and-mouth disease by the detection of antibodies to the non-structural proteins 3d, 3ab and 3abc in elisa using antigens expressed in baculovirus.the baculovirus expression system was found to be efficient at expressing the 3d, the 3ab and the 3abc non-structural proteins (nsp) of foot-and-mouth disease virus (fmdv) as antigens recognised by immune sera in elisa. elisa's using 3d, 3ab and 3abc detected antibodies from day 8 and 10 after experimental infection of susceptible cattle and sheep and cattle remained seropositive for more than 395 days. the elisa's detected antibodies against any of the seven serotypes of fmdv. the 3d elisa was ...19989739326
inactivation of foot-and-mouth disease virus by heat, formaldehyde, ethylene oxide and gamma radiation. 19989746947
vaccinia virus protein synthesis has a low requirement for the intact translation initiation factor eif4f, the cap-binding complex, within infected cells.the role of the cap-binding complex, eif4f, in the translation of vaccinia virus mrnas has been analyzed within infected cells. plasmid dnas, which express dicistronic mrnas containing a picornavirus internal ribosome entry site, produced within vaccinia virus-infected cells both beta-glucuronidase and a cell surface-targeted single-chain antibody (sfv). cells expressing sfv were selected from nonexpressing cells, enabling analysis of protein synthesis specifically within the transfected cells. ...19989765426
conformational flexibility in a highly mobile protein loop of foot-and-mouth disease virus: distinct structural requirements for integrin and antibody binding.the g-h loop of foot-and-mouth disease virus vp1 protein is a highly mobile peptide, that extends from the capsid surface and that in native virions is invisible by x-ray crystallography. in serotype c, this segment contains a hypervariable region with several continuous, overlapping, b-cell epitopes that embrace the conserved arg-gly-asp (rgd) cell attachment motif. the solvent-exposed positioning of this peptide by selective insertion into different structural frameworks of e. coli beta-galact ...19989769208
a procedure for detecting selection in highly variable viral genomes: evidence of positive selection in antigenic regions of capsid protein vp1 of foot-and-mouth disease virus.a new procedure is described for the detection of positive selection among sequences of viral proteins from highly variable viruses. the approach is based on the estimation of the rates of nonsynonymous to synonymous (ns/s) mutations to the overall genetic distances amongst the sequences compared. rates of ns/s substitutions were calculated, and the individual profiles were arranged as a function of the genetic distance observed between the complete sequences. the resulting surfaces allowed iden ...19989779622
heterotypic recognition of recombinant fmdv proteins by bovine t-cells: the polymerase (p3dpol) as an immunodominant t-cell immunogen.in this study we have examined the recognition of vp0, vp1, vp2, vp3 and p3dpol by pbmc and cd4+ t-cells from infected, vaccinated-challenged, and multiply-vaccinated (o1, a24, c1 or asia1) cattle using recombinant proteins of an o1 serotype virus. the structural protein vp1 was recognised in an homotypic context whereas vp2, vp3, vp4 and p3dpol were also recognised by t-cells from animals exposed to heterotypic viruses. only the non-structural protein p3dpol was consistently recognised by t-cel ...19989783461
new generation of african horse sickness virus vaccines based on structural and molecular studies of the virus particles.african horse sickness virus (ahsv) is a member of the genus orbivirus, which also includes bluetongue virus (btv) and epizootic haemorrhagic disease (ehdv) virus. these orbiviruses have similar morphological and biochemical properties, with distinctive pathobiological properties and host ranges. sequencing studies of the capsid proteins have revealed evolutionary relationships between these viruses. biochemical studies of the viruses together with the expression of individual proteins and prote ...19989785506
rapid selection in modified bhk-21 cells of a foot-and-mouth disease virus variant showing alterations in cell tropism.with persistent foot-and-mouth disease virus (fmdv) in bhk-21 cells, there is coevolution of the cells and the resident virus; the virulence of the virus for the parental bhk-21 cells is gradually increased, and the cells become partially resistant to fmdv. here we report that variants of fmdv c3arg/85 were selected in a single infection of partially resistant bhk-21 cells (termed bhk-rb cells). indirect immunofluorescence showed that the bhk-rb cell population was heterogeneous with regard to s ...19989811758
distinct mechanisms of antibody-mediated enzymatic reactivation in beta-galactosidase molecular sensors.the antibody-mediated reactivation of engineered escherichia coli beta-galactosidases [benito et al. (1996) j. biol. chem. 271, 21251-21256] has been thoughtfully investigated in three recombinant molecular sensors. proteins m278vp1, jx772a and jx795a display the highly antigenic g-h loop peptide segment of foot-and-mouth disease virus vp1 protein, accommodated in different solvent-exposed loops of the assembled tetramer. these chimaeric enzymes exhibit a significant increase in enzymatic activi ...19989827559
structure of the foot-and-mouth disease virus leader protease: a papain-like fold adapted for self-processing and eif4g recognition.the leader protease of foot-and-mouth disease virus, as well as cleaving itself from the nascent viral polyprotein, disables host cell protein synthesis by specific proteolysis of a cellular protein: the eukaryotic initiation factor 4g (eif4g). the crystal structure of the leader protease presented here comprises a globular catalytic domain reminiscent of that of cysteine proteases of the papain superfamily, and a flexible c-terminal extension found intruding into the substrate-binding site of a ...19989857201
molecular cloning, expression and immunological analysis of the capsid precursor polypeptide (p1) from swine vesicular disease virus.swine vesicular disease virus (svdv) is the aetiological agent of a highly contagious viral disease of pigs, whose symptoms are indistinguishable from those caused by foot-and-mouth disease virus (fmdv). the gene coding for the capsid protein precursor of svdv (p1) from a recent spanish isolate (spa/1/'93) was cloned and expressed in bacteria, and the antigenicity and immunogenicity of the recombinant product were evaluated. the recombinant p1 was recognised by antibodies against svdv induced in ...19989870584
a similar pattern of interaction for different antibodies with a major antigenic site of foot-and-mouth disease virus: implications for intratypic antigenic variation.the three-dimensional structures of the fab fragment of a neutralizing antibody raised against a foot-and-mouth disease virus (fmdv) of serotype c1, alone and complexed to an antigenic peptide representing the major antigenic site a (g-h loop of vp1), have been determined. as previously seen in a complex of the same antigen with another antibody which recognizes a different epitope within antigenic site a, the receptor recognition motif arg-gly-asp and some residues from an adjacent helix partic ...19989420281
protective immune response to foot-and-mouth disease virus with vp1 expressed in transgenic plants.it has been reported recently that genes encoding antigens of bacterial and viral pathogens can be expressed in plants in a form in which they retain native immunogenic properties. the structural protein vp1 of foot-and-mouth disease virus (fmdv), which has frequently been shown to contain critical epitopes, has been expressed in different vectors and shown to induce virus-neutralizing antibodies and protection in experimental and natural hosts. here we report the production of transformed plant ...19989445079
titration calculations of foot-and-mouth disease virus capsids and their stabilities as a function of ph.foot-and-mouth disease virus (fmdv), a non-enveloped picornavirus, is sensitive to acidic conditions. at ph values below 7 the icosahedral virus capsid, formed from 60 copies of a protomer containing four polypeptides (vp1 to 4), dissociates into 12 pentamers, releasing the viral rna. evidence suggests that this acid lability may assist fmdv cell entry via an endosomal pathway. calculations of titration curves and ph-stability profiles are presented for three different strains of fmdv, o1bfs, a1 ...19989466910
a structural model of picornavirus leader proteinases based on papain and bleomycin hydrolase.the leader (l) proteinases of aphthoviruses (foot-and-mouth disease viruses) and equine rhinovirus serotypes 1 and 2 cleave themselves from the growing polyprotein. this cleavage occurs intramolecularly between the c terminus of the l proteinases and the n terminus of the subsequent protein vp4. the foot-and-mouth disease virus enzyme has been shown, in addition, to cleave at least one cellular protein, the eukaryotic initiation factor 4g. mechanistically, inhibitor studies and sequence analysis ...19989472614
exposure of in vitro-produced bovine embryos to foot-and-mouth disease virus.the aim of this study was to investigate whether foot and mouth disease virus (fmdv) interacts with in vitro produced (ivp) bovine embryos. one milliliter of a suspension of fmdv (2 x 10(7) tcid50/ml) was added to several batches of these embryos 7 d after in vitro fertilization, by which time they had either developed to the morula/blastocyst stage (n = 256) or degenerated (n = 260). six experiments were performed in which developed or degenerated batches of embryos were incubated with fmdv for ...199810734479
development and characterization of monoclonal antibodies to foot and mouth disease virus type 'c'.five fusion experiments were conducted with spleen cells from balb/c mice immunized with purified 146s antigen of foot and mouth disease virus type 'c' (vaccine strain). monoclones (31) thus developed were isotyped as igm (3), igg1 (6), igg2a (5), igg2b (3) and igg3 (14). eleven clones isotyped as igm, igg2a and igg2b showed neutralizing activity in virus neutralization and plaque reduction tests. six of the neutralizing clones precipitated 146s virus in ouchterlony reaction. on the basis of loc ...199810093509
a cell adhesion peptide from foot-and-mouth disease virus can direct cell targeted delivery of a functional enzyme.the g-h loop of foot-and-mouth disease virus is a disordered protrusion of the vp1 protein exposed on the virion surface. this short stretch includes an arginine-glycine-aspartic acid tripeptide, a recognized integrin-binding motif, which is responsible for cell attachment and infection. eight copies of a peptide reproducing the amino acid sequence of this fmdv ligand have been displayed in solvent-exposed regions on an enzymatically active recombinant beta-galactosidase. this viral peptide segm ...199810099340
an rna virus can adapt to the multiplicity of infection.rna viruses evolve as complex distributions of mutants termed viral quasispecies. for this reason it is relevant to explore those environmental parameters that favour the selective advantage of some viral subpopulations over others. in the present study we provide direct evidence that the relative fitness of two competing viral subpopulations may depend on the multiplicity of infection (m.o.i.). two closely related subpopulations of foot-and-mouth disease virus (fmdv) of serotype c, which differ ...19989880011
assessment using elisa of the herd immunity levels induced in cattle by foot-and-mouth disease oil vaccines.the development of a liquid-phase blocking sandwich elisa (lpbe) to measure antibodies (ab) produced in cattle with the o, a and c foot-and-mouth disease virus (fmdv) types of commercial vaccines used in argentina is described. the test was specific: 99% of naïve cattle sera (n = 130) gave titres below log10 = 1.2, and none had a titre above log10 = 1.5. comparative studies with serum neutralization test (snt) using sera from cattle which received one or more vaccine doses is reported. the overa ...19989500182
the foot-and-mouth disease rna virus as a model in experimental phylogenetics.phylogenetic reconstruction methods are subject to two types of limitations: our knowledge about the true history of organisms and the gross simplification implied in the numerical simulation models of the relationships between them. in such a situation, experimental phylogenetics provides a way to assess the accuracy of the phylogenetic reconstruction methods. nonetheless, this capacity is only feasible for organisms in which replication and mutation rates are high enough to provide valuable da ...199810943380
the potential of retro-inverso peptides as synthetic vaccines.retro-inverso peptides, also known as all-d-retro or retro-enantio peptides, are composed of d-amino acids assembled in the reverse order from that of the parent l-sequence. since the orientation of the side-chains in a retro-inverso analogue is very similar to that in the parent l-peptide, this leads to a high level of antigenic cross-reactivity between the two peptides. the potential of retro-inverso peptides as synthetic vaccines has been investigated in the case of foot-and-mouth disease. a ...199815992041
detection of foot-and-mouth disease by reverse transcription polymerase chain reaction and virus isolation in contact sheep without clinical signs of foot-and-mouth disease.summary two non-vaccinated sheep were experimentally, infected with fmdv and one day later 4 other sheep were brought in contact. although the contact sheep showed no clinical signs, serology indicated that all sheep became infected. various secretion samples, taken over a period of at least one month, and various tissue samples were examined for the presence of fmdv by rt-pcr and by virus isolation. fmdv was most often found in saliva (mouth swabs), followed by nasal secretion and sera. faecal ...199822077296
rt-pcr in foot-and-mouth.summary a rt-pcr assay for the specific detection of rna sequences from foot-and-mouth disease virus (fmdv) has been developed. the procedure permits also the detection of sequences that correlate with established fmdv serotypes. a computer program that allows selection of genotype-specific primers for rt-pcr amplification was used for the identification of fmdv specific sequences for pcr amplification on rna replicase (3d) gene regions. specific, rapid and highly sensitive detection was achieve ...199822077295
diagnostic potential of mab-based elisas for antibodies to non-structural proteins of foot-and-mouth disease virus to differentiate infection from vaccination.abstract this paper summarises the development of monoclonal antibody (mab)-based immunoassays measuring antibodies to non-structural proteins of fmdv to differentiate infection from vaccination. of the three non-structural proteins 2c, 3c and 3abc evaluated in this study, the polypeptide 3abc was the most immunogenic. three elisas for the detection of antibodies to 3abc were developed. two assays rely on the competition of test sera against either a anti-3a mab or against antisera to 3abc raise ...199822077292
cattle response to foot-and-mouth disease virus nonstructural proteins as antigens within vaccines produced using different concentrations.abstract four groups of ten nine-month-old nelore heifers were used for this study. each group received one of four foot-and-mouth disease (fmd) trivalent vaccines for the duration of the experiment. the four vaccine formulations (normal, 2x, 4x and 8x) differed in 140s content to determine the serological reactivities to fmd virus (fmdv) nonstructural proteins 2c, 3abc and 3d. vaccination was by the intramuscular administration of vaccine on day 0, 180 and 360. bleedings were done at 30 days po ...199822077290
differentiating foot-and-mouth disease virus-infected from vaccinated animals with baculovirus-expressed specific proteins.abstract we had shown in preliminary studies with a small number of animals that antibodies against 2c could be detected in cattle and pigs which had been infected with fmdv but not in animals which had been vaccinated against the disease. to determine whether this test was generally applicable, seta from several hundred animals which had been vaccinated with different products in many countries have been tested in an elisa using baculovirus expressed 2c. our results show that only 1-2% of the s ...199822077289
the detection of antibodies against foot-and-mouth disease virus in sheep milk.the liquid-phase blocking elisa (lpbe) and a specific isotype assay (sia) modified for caprine/ovine igg1 and igg2 were used to detect antibodies against foot-and-mouth disease virus isolate o(1) manisa in sheep milk samples. the majority of samples from animals vaccinated 14-23 weeks previously were indistinguishable from naive sheep when tested in the lpbe but 97% were positive using the sia. all milk samples taken at 7 days after parturition from immunised animals were positive by lpbe. there ...19979504750
antigenic variation in foot and mouth disease virus type asia 1 isolates circulated during 1993-95 in india.the antigenic variation in foot and mouth disease virus (fmdv) is very high. the effective strategy to control the foot and mouth disease (fmd) in india which is a habitat of four serotypes o, a, c and asia 1, is by regular vaccination, using the vaccine strain most suitable for the local situation. india is an endemic country with the disease being widely distributed. selection of vaccine strain should therefore need the information on the circulating viruses. asia 1 causes the second largest n ...19979482590
specific interactions between human integrin alpha v beta 3 and chimeric hepatitis b virus core particles bearing the receptor-binding epitope of foot-and-mouth disease virus.purified integrin alpha v beta 3 was used in solid-phase binding studies with chimeric hepatitis b cores which carry the rgd-containing loop of vp1 protein of the foot-and-mouth disease virus (fmdv). high levels of specific binding between the integrin and the particles were detected by enzyme-linked immunosorbent assays. the binding was mn2+ cation dependent and could be competed with fibronectin, vitronectin, and the peptide grgdspk. particles in which the rgd motif had been mutated to rge fai ...19979426454
molecular analysis of foot-and-mouth disease type o viruses isolated in saudi arabia between 1983 and 1995.partial nucleotide sequence of the capsid polypeptide coding gene 1d (vp1) was determined for 68 serotype o foot-and-mouth disease viruses isolated between 1983 and 1995 from outbreaks occurring in saudi arabia. the sequences were compared with previously published sequences: 14 viruses of middle eastern origin (isolated between 1987 and 1991); and with four vaccine virus strain sequences, three originating from the middle east (o1/turkey/manisa/69, o1/sharquia/egypt/72 and o1/israel/2/85) and o ...19979440443
[a simple method for rna isolation and purification].rnas from escherichia coli cells, syrian hamster kidney cells, foot-and-mouth disease virus, and newcastle disease virus were isolated using glass fiber filters gf/f or gf/c. the rna was reversibly adsorbed on the filters in the presence of 2 m guanidine thiocyanate and 50% ethanol (or isopropanol) and eluted with water. the fraction composition of the isolated rna depended on the guanidine thiocyanate and alcohol concentrations in the adsorption and washing procedures. the rna preparations obta ...19979441599
a ribozyme targeted to cleave the polymerase gene sequences of different foot-and-mouth disease virus (fmdv) serotypes.vaccinations against foot-and-mouth disease virus (fmdv) has dramatically reduced the number of disease outbreaks. nevertheless, there are still many outbreaks in different regions around the world. in an effort to find new ways to control the disease, ribozymes able to cleave fmdv were designed and tested. in this work we tested the ability of frz4, a ribozyme targeted to the viral polymerase gene, to cleave polymerase sequences of several fmdv. homology analysis was used to choose target seque ...19979354267
a retro-inverso peptide corresponding to the gh loop of foot-and-mouth disease virus elicits high levels of long-lasting protective neutralizing antibodies.peptides corresponding to the immunodominant loop located at residues 135-158 on capsid protein vp1 of foot-and-mouth disease virus (fmdv) generally elicit high levels of anti-peptide and virus-neutralizing antibodies. in some instances, however, the level of neutralizing antibodies is low or even negligible, even though the level of anti-peptide antibodies is high. we have shown previously that the antigenic activity of peptide 141-159 of vp1 of a variant of serotype a can be mimicked by a retr ...19979356486
dissecting the roles of vp0 cleavage and rna packaging in picornavirus capsid stabilization: the structure of empty capsids of foot-and-mouth disease virus.empty capsids of foot-and-mouth disease virus (fmdv) type a22 iraq 24/64, whose structure has been solved by x-ray crystallography, are unusual for picornaviruses since they contain vp2 and vp4, the cleavage products of the protein precursor vp0. both the n terminus of vp1 and the c terminus of vp4, which pack together close to the icosahedral threefold symmetry axis where three pentamers associate, are more disordered in the empty capsid than they are in the rna-containing virus. the ordering o ...19979371640
efficient neutralization of foot-and-mouth disease virus by monovalent antibody binding.neutralization of an aphthovirus by monovalent binding of an antibody is reported. foot-and-mouth disease virus (fmdv) clone c-s8c1 was neutralized by monoclonal antibody (mab) sd6, which was directed to a continuous epitope within a major antigenic site of the g-h loop of capsid protein vp1. on a molar basis, the fab fragment was at most fivefold less active in neutralization than the intact antibody, and both blocked virus attachment to cells. neither the antibody nor the fab fragment caused a ...19979371652
characterization of an internal ribosomal entry segment within the 5' leader of avian reticuloendotheliosis virus type a rna and development of novel mlv-rev-based retroviral vectors.the murine leukemia virus (mlv)-related type c viruses constitute a major class of retroviruses that includes numerous endogenous and exogenous mammalian viruses and the related avian spleen necrosis virus (snv). the mlv-related viruses possess a long and multifunctional 5' untranslated leader involved in key steps of the viral life cycle--splicing, translation, rna dimerization, encapsidation, and reverse transcription. recent studies have shown that the 5' leader of friend murine leukemia viru ...19979382952
escape mutants of foot-and-mouth disease virus selected by monoclonal antibodies directed to a trypsin-sensitive neutralization epitope.five monoclonal antibodies (moabs) against indian reference/vaccine strain of foot-and-mouth disease (fmd) virus subtype a22 (ind17/77) and a guinea pig antibody against a synthetic peptide representing amino acids (aa) 136-151 of vp1 polypeptide of a22 virus were used in the study. all the antibodies either failed to react or showed a reduced reactivity with trypsin-treated (tt)-146 s virus particles in enzyme-linked immunosorbent assay (elisa), and could neutralize the infectivity of the refer ...19979385400
one-tube and one-buffer system of rt-pcr amplification of 1d gene of foot-and-mouth disease virus field isolates.a method of reverse transcription (rt) and polymerase chain reaction (pcr) amplification of 1d (vp1) gene of foot-and-mouth disease (fmd) virus using one reaction mixture containing both avian myeloblastosis virus (amv) reverse transcriptase (rtase) and tfl dna polymerase is described. the procedure was time saving, made use of a single buffer for both rt and subsequent amplification and performed better than the two-step procedure usually conducted with moloney murine leukemia virus (mmlv) rtas ...19979385403
the non-structural polyprotein 3abc of foot-and-mouth disease virus as a diagnostic antigen in elisa to differentiate infected from vaccinated cattle.a diagnostic assay to differentiate antibodies induced by foot-and-mouth disease virus (fmdv) infection from those induced by vaccination was developed. the test is an indirect-trapping elisa which uses a monoclonal antibody to trap the non-structural 3abc-fmdv polypeptide expressed in e. coli. experimental and field sera from naive, vaccinated and infected cattle were examined. using the established threshold of 0.20 optical density units, the sensitivity of the assay was 100%, as all the exper ...19979413510
[seroprevalence of viral infections in llamas (lama glama) in the republic of argentina].this study reports the seroprevalence of bovine viral infections in llamas (lama glama) in argentina. this is the first study made in the country including 390 llamas and testing antibodies against eight viruses. samples were collected from nine farms distributed in three different provinces: buenos aires, córdoba and jujuy. the samples were tested for antibodies against eight viruses known to infect cattle: bovine herpesvirus type 1 (bhv-1), bovine viral diarrhea virus (bvdv), bovine adenovirus ...19979229724
computer simulations to identify in polyproteins of fmdv ok1 and a12 strains putative nonapeptides with amino acid motifs for binding to bola class i a11 and a20 haplotype molecules.the computer program "findpatterns" was used to search fmdv- (ok1 and a12 strains) coded structural and nonstructural proteins for the availability of putative proteasome-generated nonapeptides with motifs reported for bola class i a11 and a20 haplotypes. these bola class i a11 and a20 nonapeptide motifs are identical to motifs of nonapeptides that interact with the peptide binding grooves of hla class i b35 and b27 haplotypes, respectively. the computer findpattern program was used to analyze t ...19979237351
differentiation of the seven serotypes of foot-and-mouth disease virus by reverse transcriptase polymerase chain reaction.a strategy for reverse transcriptase polymerase chain reaction (rt-pcr) using multiple primers was developed to detect and to differentiate the seven serotypes of foot-and-mouth disease virus (fmdv) simultaneously, quickly and accurately. the development of the test was carried out on virus isolates grown in tissue culture prior to cdna synthesis and pcr using various sets of primers. primers p33 and p32 were used for the consensus pcr to detect fmdv regardless of the serotype. positive cdna was ...19979274816
preparation and characterization of monoclonal antibodies to foot-and-mouth disease virus type asia-1.eight clones of hybrid cells secreting monoclonal antibodies to foot-and-mouth disease virus type asia-1 were prepared; three of them neutralized viral infection. the specificity of the monoclonal antibodies was analyzed by various immunoenzyme assays using 146s viral particles, trypsin-treated 146s particles, 12s particles, and certain viral polypeptides. the epitopes unique for virus type asia-1 and conservative among several types were detected on the surface of viral particles. epitopes on t ...19979275286
antigenic features of foot-and-mouth disease virus serotype asia1 as revealed by monoclonal antibodies and neutralization-escape mutants.neutralizable antigenic sites/epitopes of serotype asial foot-and-mouth disease virus (strain ind63/72) were identified using monoclonal antibodies (mabs) and their neutralization-escape mutants. relative affinity/reactivity of the mabs for viral (both native and trypsin-cleaved) and subviral antigens in enzyme-linked immunosorbent assay (elisa) showed dominance of trypsin-sensitive and conformation-dependent neutralizable antigenic sites. characterization of neutralization escape mutants identi ...19979282776
natural adaption to pigs of a taiwanese isolate of foot-and-mouth disease virus. 19979290197
[use of protease 3c and foot-and-mouth disease virus rna polymerase hybrid proteins, synthesized in escherichia coli, for diagnosis]. 19979297102
nucleotide sequence of the p1 region of foot-and-mouth disease virus strain o1 caseros.it has been shown that variation of antigenic site i in vp1 of foot-and-mouth disease virus (fmdv) plays an important role in the antigenic diversification of this virus. however, the o1 campos strain is able to efficiently cross-protect cattle against the o1 caseros strain, despite having a different sequence in the site i. in this paper we report and compare the p1 coding region for the capsid proteins of fmdv o1 caseros and o1 campos. the deduced amino acid sequence showed a total of 31 amino ...19979311571
plasmid dna encoding replicating foot-and-mouth disease virus genomes induces antiviral immune responses in swine.dna vaccine candidates for foot-and-mouth disease (fmd) were engineered to produce fmd virus (fmdv) particles that were noninfectious in cell culture or animals. the prototype plasmid, pwrm, contains a cytomegalovirus immediate-early promoter-driven genome-length type a12 cdna followed by the bovine growth hormone polyadenylation site. bhk cells transfected with this plasmid produced virus, but the specific infectivity of pwrm was much lower than that achieved with in vitro-generated rna genomes ...19979311823
foot-and-mouth disease virus and poliovirus particles contain proteins of the replication complex.nonstructural proteins 2c, 3cd, 3c, and 3d, and the cellular protein actin, are present in highly purified preparations of foot-and-mouth disease virus (fmdv) and poliovirus. they remain bound in variable amounts to the rnas when the rnas are extracted from the viruses with phenol or phenol-sodium dodecyl sulfate (sds) and, for fmdv, when the rna is released from the particles by a lowering of the ph below 7. rna prepared by these methods is rapidly degraded at 37 degrees c, particularly in the ...19979311848
contamination of animal products: the minimum pathogen dose required to initiate infection.when an animal product contains a low level of contamination (perhaps less than the minimum infective dose of a pathogen as determined experimentally), the theoretical probability remains that if a large number of animals are exposed to that product, at least one animal in the group will become infected. such an infected animal could start an outbreak of the disease. these aspects, therefore, should be considered when risk assessments are performed. foot and mouth disease virus in milk is used a ...19979329105
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