TitleAbstractYear(sorted ascending)
nucleotide sequence heterogeneity of the rna from a natural population of foot-and-mouth-disease virus.the genomic rna from isolates of foot-and-mouth-disease virus (fmdv) of serological types o or c obtained during epizootic outbreaks have been analysed by two-dimensional gel electrophoresis of the t1 rnase-generated oligonucleotides (t1 fingerprinting). among virus isolates that are closely related serologically, 4-12 oligonucleotide changes were detected constitute the genome, the variations affect 0.7%-2.2% positions in fmdv rna. higher nucleotide-sequence divergence exists between the genomi ...19806260578
[immune response in guinea pigs to foot-and-mouth disease virus. study of the biological activities of igg subclasses in hyperimmunized animal sera]. 19806292997
symposium: international challenges and perspectives: internationalism and survival of foot-and-mouth disease virus in cattle and food products.foot-and-mouth disease is a serious world-wide economic disease of livestock and diverse animal species. the closing of borders to infected countries is a frequent aftermath of disease outbreaks. historically, animals and animal products have been implicated as vehicles for transmission of the disease. control programs encompass stringent importation policies, vaccination, quarantine, and slaughter. joint efforts have been instituted successfully in previous control campaigns and would be the lo ...19807400424
[use of the radial immunodiffusion test in the study of foot-and-mouth disease viruses].the radial immunodiffusion test (rit) was used in the study of the quantitative interrelations between three subtypes of type a of the foot-and-mouth disease virus--a5, a10, and a22. a reverse proportional correlation was demonstrated between the size of the precipitation circles and the antibody concentration in the homologous sera, and a direct proportional correlation between the diameter of the circles and the amount of the antigen used. it was shown that one and the same antigen produced pr ...19816283723
molecular cloning of foot and mouth disease virus genome and nucleotide sequences in the structural protein genes.foot and mouth disease virus (fmdv), of the family picornaviridae, consists of a single-stranded rna (approximately 8,000 nucleotides), the translation of which is initiated on the 3' side of a 150-nucleotide poly(c) tract and yields a single polyprotein which is processed by host cell proteases into four primary products (fig. 1). one or more virus-specified proteases further cleave these into the final products, the capsid proteins (vp1-4) being derived from the precursor p88 (for review see r ...19816261157
isolation of a soluble and template-dependent foot-and-mouth disease virus rna polymerase. 19816263001
visualization by chilling of protein bands in polyacrylamide gels containing 8 m urea: preparation and quantitation of foot-and-mouth disease virus capsid proteins. 19816263128
nucleotide sequence and corresponding amino acid sequence of the gene for the major antigen of foot and mouth disease virus.a segment of 1160 nucleotides of the fmdv genome has been sequenced using three overlapping fragments of cloned cdna from fmdv strain o1k. this sequence contains the coding sequence for the viral capsid protein vp1 as shown by its homology to known and newly determined amino acid sequences from this man antigenic polypeptide of the fmdv virion. the structural gene for vp1 comprises 639 nucleotides which specify a sequence of 213 amino acids for the vp1 protein. the coding sequence is not flanked ...19816264400
differential precipitation of foot and mouth disease virus proteins made in vivo and in vitro by hyperimmune and virus particle guinea pig antisera. 19816264693
serological differentiation of foot-and-mouth disease virus on electron microscope grids coated with protein a and antibody.a serological technique using electron microscope grids coated with protein a and antiserum was able to detect foot-and- mouth disease virus particles in oesophageal-pharyngeal fluids from infected cattle without the need for prior concentration of the sample. the technique was adapted to differentiate serologically among foot-and-mouth disease virus types a, o and c with antigen-adsorbed sera. when grids were coated with heterotypic antigenadsorbed antisera, the homotypic antigen could be obser ...19816280815
the use of highly concentrated purified (by a large scale method) and long term liquid nitrogen stored foot-and-mouth disease viruses for the preparation of vaccines: physico-chemical quality controls and potency tests after 1974 a new industrial technique for concentration and purification of fmd virus was presented at the oie conference. the bulk inactivated virus from this technique was stored in liquid nitrogen vapour until required for vaccine formulation. in 1981, having applied this technique regularly for seven years, we now describe the results obtained and the advantages gained in the field of trivalent o, a, c bovine vaccine production. vaccines prepared from such bulk virus stocks after several years ...19816281108
observations and implications of proteolysis in preparations of foot-and-mouth disease virus.the integrity of the vp1 protein of foot-and-mouth disease virus was assessed by polyacrylamide gel electrophoresis (following storage at 4 degrees c of conventional tissue culture preparations and concentrated preparations of the virus. there was little evidence of vp1 degradation in tissue culture filtrates whereas considerable degradation was observed throughout a range of different concentrates. the use of the proteolytic enzyme inhibitor 'trasylol' appeared to inhibit vp1 degradation in som ...19816281109
[molecular biology of the foot-and-mouth disease virus]. 19816285123
a micro-enzyme-lavelled immunosorbent assay (micorelisa) for the detection of foot-and-mouth disease virus antigen and antibody.the indirect technique of a micro-enzyme-labelled immunosorbent assay (microelisa) was standardized and found efficient in detecting the foot-and-mouth disease virus antigen in cell culture fluids, mice carcases and cattle tongue epithelium as well as the antibody titre of sera.19816112866
subtyping of foot-and-mouth disease virus by the micro-enzyme-labelled immunosorbent assay (microelisa).the micro-enzyme-labelled immunosorbent assay (microelisa) was used successfully for the subtyping of foot-and-mouth disease (fmd) virus strains recovered from field outbreaks. the rabbit anti-guinea pig globulin-peroxidase conjugate employed in the indirect microelisa has the advantage of being used with any of the seven types of fmd virus.19816112867
a sensitive method for the detection and isolation of recombinants of foot-and-mouth disease virus.recombination between temperature-sensitive (ts) mutants of foot-and-mouth disease (fmd) virus was examined, using an infectious centre technique that was more sensitive (approx. 30-fold) than the conventional virus yield test. the test involved a brief incubation of the mixedly infected cells at the permissive temperature to allow recombination to occur followed by assay at the restrictive temperature to select for those cells in which recombination had occurred. with crosses involving widely s ...19816267181
removal of the genome-linked protein of foot-and-mouth disease virus by rabbit reticulocyte lysate.rabbit reticulocyte lysate cleaves the genome-linked protein vpg from foot-and-mouth disease virus (fmdv) rna. this activity could be reliably monitored since removal of the protein resulted in a change in migration in polyacrylamide gels of the small specific 5' and fragment of the rna (s fragment). the unlinking activity cleaved the bond between the tyrosine residue of vpg and the rna to leave a 5' phosphate on the rna. the 5' sequence of the rna from which vpg had been removed by rabbit retic ...19816268821
identification of a protein kinase activity in purified foot- and-mouth disease virus.purified preparations of foot-and-mouth disease virus types a, o, and c contain a protein kinase activity which can transfer the gamma phosphate of [32p]atp to virion structural proteins vp2 and vp3 and exogenous acceptor proteins. utilizing protamine sulfate as an acceptor, the kinase activity can be demonstrated in disrupted virus but not in intact virus. the enzyme is heat labile with optimal activity at ph 7 or greater. serine residues of protamine sulfate were identified as the amino acid p ...19816268834
effect of mutation on the virulence in mice of a strain of foot-and-mouth disease virus.twenty-eight mutations, representing mutation in five different polypeptide-coding regions of the foot-and-mouth disease genome, were examined for their effect on the virulence of the virus for suckling mice. five types of mutation were examined: temperature-sensitive (ts), electrophoretic (e), co-variant temperature-sensitive and electrophoretic (ts/e), guanidine-resistant (gs+) and putative co-variant guanidine-resistant and electrophoretic (gs+/e). all the ts mutations and three out of the 11 ...19816270249
temperature-sensitive rna polymerase mutants of a picornavirus.temperature-sensitive (ts) rna polymerase mutants of a picornavirus are reported. two foot-and-mouth disease virus (fmdv) mutants designated ts 22 and ts 115 have been characterized. as judged by isoelectric focusing, both have charge alterations in p56a, the fmdv rna polymerase protein. virus rna synthesis in cells infected with the mutants is severely impaired at the nonpermissive temperature. rna polymerase purified from baby hamster kidney cells infected with these mutants exhibits a marked ...19816270678
heterogeneity of infection-associated particles in foot-and-mouth disease virus. 19816270879
vesicular exocytosis of foot- and -mouth disease virus from mammary gland secretory epithelium of infected cows.foot-and-mouth disease virus particles were observed by electron microscopy in the cytoplasma of alveolar secretory cells of the bovine mammary gland after contact exposure of uninfected cows to pits with foot-and-mouth disease. virus, contained in membrane-limited vesicles, was released from the basal and peranuclear portions of the cells into the intracellular and extracellular spaces by an exocytotic mechanism similar to that of the release of th milk-fat globule. virus was released into the ...19816271913
cloned viral protein vaccine for foot-and-mouth disease: responses in cattle and swine.a dna sequence coding for the immunogenic capsid protein vp3 of foot-and-mouth disease virus a12, prepared from the virion rna, was ligated to a plasmid designed to express a chimeric protein from the escherichia coli tryptophan promoter-operator system. when escherichia coli transformed with this plasmid was grown in tryptophan-depleted media, approximately 17 percent of the total cellular protein was found to be an insoluble and stable chimeric protein. the purified chimeric protein competed e ...19816272395
[comparative trial of the immunogenic properties of commercial foot-and-mouth virus strains].comparative investigations on the antigenic relation and the immunogenic properties of the foot-and-mouth disease virus types o, a, and c. were carried out with the aid of the quantitative cft and experiments with guinea pigs. it was established that the viruses of a given type were closely related antigenically and belonged to one and the same subtype group (r greater than of equal to 70 per cent). immunogenicity studies revealed that strains o1y a5f, c 564, and cf were best in terms of immunog ...19816272473
production in b. subtilis of hepatitis b core antigen and a major antigen of foot and mouth disease virus. 19816273732
characterization of a 70s polyuridylic acid polymerase isolated from foot-and-mouth disease virus-infected cells.a polyuridylic acid polymerase complex isolated from foot-and-mouth disease virus-infected cells sedimented at 70s in a sucrose gradient and appeared in the exclusion volume of an agarose column whose molecular weight cutoff was 5 x 10(6). phenol extraction of the complex yielded a heterogeneous band of virus-specific rna and an apparently host cell-derived 4.5 to 5s rna, both of which are essentially single stranded. neither rna served as a template in the cell-free enzyme reaction. polyacrylam ...19816275123
thermal stability of foot-and-mouth disease virus.the thermal stabilities of 146s component of seven strains of foot-and-mouth disease virus were found to differ considerably. inactivation of infectivity with acetylethyleneimine (aei) reduced the thermal stabilities of all but one of the viruses. treatment of aei inactivated and control virus preparations with glutaraldehyde stabilized 146s particles to a considerable extent, whereas treatment with dimethyl suberimidate was less effective. in similar experiments with 75s, natural empty particle ...19816277281
relationship between plaque size and the immunising ability of the foot-and-mouth disease virus sat 1 nig 10/75. 19816277283
cloning of cdna of major antigen of foot and mouth disease virus and expression in e. coli.double-stranded dna copies of the single-stranded genomic rna of foot and mouth disease virus have been cloned into the escherichia coli plasmid pbr322. a restriction map of the viral genome was established and aligned with the biochemical map of foot and mouth disease virus. the coding sequence for structural protein vp1, the major antigen of the virus, was identified and inserted into a plasmid vector where the expression of this sequence is under control of the phage lambda pl promoter. in an ...19816258084
neutralization of foot-and-mouth disease virus. i. sensitization of the 140s virion by antibody also reactive with the 12s protein subunit.the in vitro interaction of foot-and-mouth disease virus (fmdv) with an immune serum resulted in a fraction of virus which failed to be neutralized. this inability of antibody to neutralize the entire population of a virus preparation was studied with emphasis on the antigenic specificity of the antibody-virus reaction. antibody to fmdv recognized multiple antigenic determinants. immunoabsorbent fractionation of the serum into 12s subunit cross-reactive and 140s virion-specific antibody revealed ...19816169797
quantification, characterisation and safety testing of foot-and-mouth disease virus antigens eluted from alhydrogel vaccines.different methods for the elution and the concentration of fmdv-antigen from formaldehyde-inactivated alhydrogel vaccines were compared. with locally produced vaccines the best results were obtained if the antigen was eluted with potassium phosphate buffer and the concentration was performed by ultrafiltration. final recoveries of 50% of the 140-s antigen could be obtained. for innocuity control 1-3 mg of 140-s antigen was eluted from 21 vaccine. sds-polyacrylamide gel electrophoresis and iso-el ...19816176487
detection and quantification of igm, iga, igg1 and igg2 antibodies against foot-and-mouth disease virus from bovine sera using an enzyme-linked immunosorbent assay.a simple solid-phase enzyme immunoassay is described for the detection of antibody classes showing activity against foot-and-mouth disease (fmd) virus in bovine sera. the assay achieves a preliminary separation of the specific class of antibody from other serum proteins through immuno-adsorption to class-specific immunoglobulin-coated wells of micro-titre plates. the specific antibody is reacted with fmd virus, which is then detected by an enzyme-labelled anti virus igg.19816257779
location and characterization of the antigenic portion of the fmdv immunizing protein.purified foot-and-mouth disease virus (fmdv) to type o1k was treated with several endopeptidases of differing specificity. the immunizing protein vpthr was cleaved into two detectable fragments by all enzymes except for glutamic acid-specific staphylococcus aureus v8 protease. the longest fragments were generated by mouse submaxillary gland protease and the shortest by trypsin treatment of the intact virion. several fragments, including the peptides resulting from the cyanogen bromide (cnbr) cle ...19826176678
stimulation by heterotypic antigens of foot-and-mouth disease virus antibodies in vaccinated cattle.immunisation of cattle with foot-and-mouth disease virus failed to raise a level of antibody that provides protection against heterotypic challenge. further the 12s substructure, produced from the 146s particle, was ineffective in providing protection against challenge by homotypic virus. these findings suggest considerable antigenic differences in the virus serotypes and between the virus and its substructure. inoculation of homologous 12s and heterologous 1246s and 12s antigens into vaccinated ...19826179141
synthesis of long dna molecules complementary to foot-and-mouth disease virus rna. 19826181010
monoclonal antibodies against foot-and-mouth disease virus 146s and 12s particles.this paper is the first description of monoclonal antibodies specific for foot-and-mouth disease virus (fmdv). using these antibodies, it was possible to distinguish similar and unique antigenic sites on complete (146s) or subunit (12s) virus particles. some of these monoclonal antibodies could also distinguish between 12s subunits made by acid degradation of 146s virus (12sa) and those viral components found in infected cell lysates which sediment in sucrose density gradients as "12s subunits" ...19826186225
antibodies against a preselected peptide recognize and neutralize foot and mouth disease virus.a major antibody combining site on foot and mouth disease virus (fmdv) serotype o1k has been identified in a predicted surface helix of viral protein 1 (vp1) between amino acid residues 144 and 159. a hexadecapeptide covering this sequence elicits high titers of antibodies that specifically recognize and neutralize fmdv. the high quality of the immune response is attributed to a particularly stable conformation of the antigenic amino acid sequence, which is most likely an alpha-helix.19826203738
long distance transport of foot-and-mouth disease virus over the sea.the conditions required for the transport of foot-and-mouth disease (fmd) virus in the atmosphere over long distances and in sufficient concentrations to cause infection in exposed animals are described. using these factors a series of 23 outbreaks of fmd in europe, where the original outbreaks were separated from later outbreaks by sea passage, have been investigated. the findings obtained support the hypothesis that under certain conditions the airborne transmission of fmd over a long sea pass ...19826278697
cores in foot-and-mouth disease virus. 19826278713
the adsorption and degradation of foot-and-mouth disease virus by isolated bhk-21 cell plasma membranes. 19826278720
comparison of the amino acid sequence of the major immunogen from three serotypes of foot and mouth disease virus.cloned cdna molecules from three serotypes of fmdv have been sequenced around the vp1-coding region. the predicted amino acid sequences for vp1 were compared with the published sequences and variable regions identified. the amino acid sequences were also analysed for hydrophilic regions. two of the variable regions, numbered 129-160 and 193-204 overlapped hydrophilic regions, and were therefore identified as potentially immunogenic. these regions overlap regions shown by others to be immunogenic ...19826298715
ultrastructural changes and antigen localization in tissues from foot-and-mouth disease virus-infected guinea-pigs.foot-and-mouth disease virus (fmdv)-induced ultrastructural changes in guinea-pig tongue, heelpad, mammary and liver tissues were examined using scanning and transmission electron microscopy. fmdv infection caused cell rounding and the release of virus in membrane limited vesicles in the animal tissues similar to that seen in other work in cell cultures. microfilaments were present which may be responsible for cell rounding. immunoperoxidase labeling revealed the attachment of the virus-infectio ...19826298989
genetically engineered viral vaccines--prospects for the future.genetic engineering (recombinant dna technology)--the revolution in molecular biology--has enabled us to isolate any genes from any source in a pure form, and to move them from one cell to another. it has become possible to program bacterial or yeast cells with foreign genes and force the new host to produce commercially valuable proteins (e.g. hormones, enzymes, diagnostic reagents). it is now also possible to produce viral and bacterial antigens in various types of cells. we hope that this wil ...19826763495
immunosuppression in bovine trypanosomiasis: response of cattle infected with trypanosoma congolense to foot-and-mouth disease vaccination and subsequent live virus challenge.the primary and secondary antibody responses to foot-and-mouth disease virus vaccine were examined in cattle infected with trypanosoma congolense and the response of some of these animals to live foot-and-mouth disease virus challenge was assessed. infected groups of cattle had rather lower antibody responses than uninfected control cattle after primary vaccination but the antibody titres were not significantly depressed until after secondary vaccination. these levels remained depressed for the ...19826285433
foot-and-mouth disease virus: immunogenicity and structure of fragments derived from capsid protein vp and of virus containing cleaved vp.peptide fragments were obtained from the immunogenic capsid protein vp3, ca. 24 kilodaltons (kd), of foot-and-mouth disease virus type a12 119ab by three procedures: (1) spontaneous proteolysis of in virion vp3 in tissue cultures to produce a 15 kd peptide, designated s fragment; (2) trypsin treatment of purified virus to produce a 16 kg peptide, designated t fragment; and (3) cyanogen bromide cleavage of purified vp3 to produce a 13 kd fragment. following isolation and purification by gel elect ...19826287701
difference in protective immunity of the tongue and feet of guinea pigs vaccinated with foot-and-mouth disease virus type a12 following intradermolingual and footpad challenge. 19826287702
portraits of viruses: foot-and-mouth disease virus. 19826288615
the elution of foot-and-mouth disease virus from vaccines adjuvanted with aluminium hydroxide and with saponin. 19826290497
susceptibility of squirrel and cebus monkeys to foot-and-mouth disease virus. 19826290662
a novel structure seen when foot-and-mouth disease virus-induced poly (u) polymerase acts in a cell-free system. 19826290687
serological analysis of recent type o foot-and-mouth disease virus isolates from europe. 19826291221
partial characterization of temperature-sensitive mutants of foot-and-mouth disease virus, o1 caseros strain.the preliminary characterization of four temperature-sensitive (ts) mutants of the o1 caseros strain of foot-and-mouth disease virus is described. two mutants, ts 6 and ts 40, showed a very low rna synthesis rate at nonpermissive temperature and were classified phenotypically as rna(-). shift-up experiments demonstrated an incapacity to organize the rna replicative process at nonpermissive temperature. another mutant (ts 139) behaved phenotypically as rna(+) and its virions were more thermolabil ...19826292127
concentration of foot-and-mouth disease virus in milk of cows infected under simulated field conditions. 19826292275
neutralization of foot-and-mouth disease virus. ii. further parameters related to the sensitization of the 140s virion by antibody.the reaction of foot-and-mouth disease virus (fmdv) with 12s subunit/140s virion cross-reactive (sensitizing) antibody was studied in order to elucidate the requirements for neutralization versus sensitization. the presence of sensitizing antibody in immune serum caused an atypical in vitro neutralization response curve and a non-neutralized fraction. cell-associated (cytophilic) antibody was not present in the system. dissociation of the immune complex was not a factor and sensitized virus adso ...19826292352
the positively charged structural virus protein (vp1) of foot-and-mouth disease virus (type o1) contains a highly basic part which may be involved in early virus-cell interaction.polypeptides of 'trypsin-resistant' (tr) variants of foot-and-mouth disease virus type o1 (bfs 1860) were analysed by electrofocusing and two-dimensional gel electrophoresis. in contrast to parent o1 virus, trypsin treatment of these variants did not reduce their infectivity and their ability to attach to susceptible cells, although vp1 was cleaved as in the parent virus. in otr1, one of the cloned isolates, an additional polypeptide (vpa) with a mol. wt. approx. 31 x 10(3) (31k), was found whic ...19826292355
application of rnase t1 one- and two-dimensional analyses to the rapid identification of foot-and-mouth disease viruses.the analysis of several isolates of foot-and-mouth disease virus by rnase t1 fingerprinting of the 32p-labeled rna is described. it has been shown that use of the 35s induced rna instead of the virus particle rna has two advantages. (i) about 40 times more radioactivity is incorporated into the induced rna. (ii) the rna can be prepared much more rapidly, thus increasing the value of the technique in rapid diagnosis. one-dimensional maps, in which the rnase t1 oligonucleotides are separated accor ...19826281186
three strains of european foot-and-mouth disease virus are highly conserved in the 3'-termini and highly variable in the genes of two capsid proteins.restriction enzyme-generated subgenomic fragments of cloned cdna prepared from rna of the strain o1 kaufbeuren (o1k) of foot-and-mouth disease virus (fmdv) were compared qualitatively and quantitatively for sequence complementarity with radioactive rna from strains c oberbayern (cobb) and a2 spain (a2s) in hybridization experiments on nitrocellulose membranes. quantitative comparison of nucleic acid sequences neighbouring (c obb/o1k) or including (a2s/o1k) the 3' end of the virus genomes demonst ...19826281370
the nucleotide sequence of cdna coding for the structural proteins of foot-and-mouth disease virus.the complete nucleotide sequence of cdna coding for the structural capsid polypeptides of foot-and-mouth disease virus (fmdv) (strain a(10)61) has been determined. portions of the flanking sequence coding for the nonstructural proteins p20a and p52 are also provided. the three larger structural polypeptides vp1, vp2 and vp3 have unmodified mrs of 23248, 24649 and 24213, respectively. the size of the smaller polypeptide, vp4, can only be estimated at 7360 because the 5'-limit of its coding region ...19826282711
differentiation of foot-and-mouth disease virus strains using a competition enzyme-linked immunosorbent assay.foot-and-mouth disease virus isolates were compared using solid-phase competition and indirect microenzyme-linked immunosorbent assays. results were compared to those obtained from complement fixation tests. similar relationships between the isolates were obtained using the indirect enzyme immunoassay and complement fixation tests. the competition assay was more discriminatory and the results did not always correlate with the other two assays.19826282918
comparative immunogenicity of 146s, 75s and 12s particles of foot-and-mouth disease virus. 19826293410
further characterization of a protein kinase from foot-and-mouth disease virus.acid disruption of foot-and-mouth disease virus released a protein kinase activity that sedimented at less than 7s. this enzyme was separated into three peaks of activity by ion-exchange and hydroxylapatite chromatography. analysis of the various enzyme fractions by polyacrylamide gel electrophoresis and silver staining revealed that one of the fractions lacked the major virion structural proteins, but still contained two or three other polypeptides. this enzyme phosphorylated mainly one protein ...19826294327
a tandem repeat gene in a picornavirus.three closely related genes for the small genome-linked protein (vpg) of picornaviruses have been identified by sequence analysis as a tandem repeat in the genome of foot and mouth disease virus (fmdv), strain o1k. this unusual structure was also found in the genome of strain c1o, belonging to a different fmdv serotype. predicted biochemical properties of the three vpg gene products are in excellent agreement with the data from protein analysis of a heterogeneous vpg population from a third fmdv ...19826294604
nature of the antibody response to the foot-and-mouth disease virus particle, its 12s protein subunit and the isolated immunizing polypeptide vp1.inoculation of inactivated 146s foot-and-mouth disease virus particles into guinea-pigs elicited the formation of neutralizing antibody and the serum had a 10-fold higher titre in radioimmunoassay (ria) with 146s particles than with the 12s virus subunit. in contrast, a single inoculation of the 12s subunit or the isolated polypeptide vp1 elicited the formation of antibody having a much lower titre in ria with the 146s particle than with the 12s subunit and low or undetectable neutralizing activ ...19826296284
air sampling of pigs infected with foot-and-mouth disease virus: comparison of litton and cyclone samplers.the air in looseboxes containing groups of pigs in the acute stage of foot-and-mouth disease was sampled simultaneously with two air-sampling devices: a large volume sampler (litton) and a cyclone sampler. although the cyclone sampler was slightly less efficient at trapping airborne virus it was easier to operate. when pigs were sampled individually within a 610 litre cabinet using the cyclone sampler, the mean recovery of virus over a 24 hour period was log10 8 x 6 tcid50 per animal. this figur ...19826296955
competition for cellular receptor sites among selected aphthoviruses.the competition between different types of aphthoviruses (foot-and-mouth disease virus [fmdv]) for receptor site utilization was determined. the southern african territories (sat) types of fmdv absorbed poorly to bhk-21 cells as measured by a radioactivity binding assay but grew to relatively high titers on these cells. on bk cells, however, all three sat types bound well and competed with each other for receptor sites. in addition, unlabeled fmdv types a12 and o1b were able to completely inhibi ...19826297430
variations in the buoyant density of foot-and-mouth disease virus strains.some of the factors which effect the buoyant density in caesium chloride of foot-and-mouth disease virus were investigated. under standard conditions, the buoyant densities of a range of vaccine virus strains, representing all seven serotypes, were found to be unrelated to their potential of being formulated into effective vaccines. in some virus strains, a small amount of naturally occurring high and/or low density components were observed and these components were examined in more detail in on ...19826284093
antibody titres to african horse sickness, swine vesicular disease and foot-and-mouth disease viruses in samples from equidae in malta, 1975. 19826284298
sensitivity of seven different types of cell cultures to three serotypes of foot-and-mouth disease virus.the ability of bovine tongue origin foot-and-mouth disease virus serotypes a, o and c to replicate in seven different types of cell cultures was studied. primary and secondary calf thyroid cells were equivalent in susceptibility to bovine kidney cell cultures passaged up to five times. calf thyroid cells lost their susceptibility after two passages. cryopreserved bovine kidney cell cultures passaged three and four times were equivalent in susceptibility to sensitive calf thyroid and bovine kidne ...19826284329
interactions between saponin and 146s particles of foot-and-mouth disease virus. 19826284760
qualitative assessment of 146 s particles of foot-and-mouth disease virus in preparations destined for vaccines. 19826284761
guanidine and heat sensitivity of foot-and-mouth disease virus (fmdv) strains.a study of the ability of 49 strains of fmd virus to replicate in bhk-21 monolayer cells maintained under a standard agar overlay containing 5.2 mm guanidine hydrochloride and to withstand heat inactivation at 54 degrees c for 1 h showed that strains belonging to serotypes c, o and asia 1 were generally more resistant to guanidine and heat stable than the sat 1, 2 and 3 serotypes. the type a viruses as a whole occupied an intermediate position between these two groups. in vitro passage in bhk-21 ...19826284836
[early stages in the replication of aphthous fever virus. kinetics of partial degradation and sites for the establishment of penetrating residual virus].at input multiplicities between 5-10 ufp/cell fmdv o1 caseros adsorb in bhk21 clon 13 cells at a rate of 5-20% depending whether cells are in suspension or in monolayers. at least four washings with medium are required to eliminate non specifically adsorbed virions. the remaining attached virus appears to be in contact with "specific" receptors of the cytoplasmic membrane. after penetration, 80% of virus became degraded to slow molecular weight material which is detected at first in the subcellu ...19826101001
studies on the stability of foot-and-mouth disease virus using absorbance - temperature profiles.the main immunogenic component of fmd virus harvests is the intact 140s virus particle. for the production of stable vaccines it is important to ensure that virus strains having a stable capsid should be used. the method of measuring the heat stability of fmd virus by following the increase in optical density of purified virus during capsid breakdown as the temperature is increased was described in 1964 (p. bachrach, 1964, j. mol. biol 8. 348). we have investigated this technique in the hope tha ...19836329854
immunogenicity of foot-and-mouth disease virus type o1 replicated in either monolayer or suspended bhk cell system.the efficacy of vaccines formulated from the 10th passage of foot-and-mouth disease virus (fmdv) type o1 in monolayer baby hamster kidney (bhk) cells and the 8th passage in suspension bhk cells was compared in steers. the vaccines were inactivated with ethylenimine, contained an equal amount of antigen and were emulsified in oil-adjuvant. six animals were vaccinated with each vaccine. during the challenge of immunity (91 days post-vaccination, dpv), one out of the six steers from the monolayer v ...19836297845
using genetically engineered bacteria for vaccine production.we concluded from this and our earlier work that biosynthetically produced fmdv vp1-specific fusion proteins are effective vaccines. whether this method of vaccine production can be extended to many other immunogenic proteins from other organisms is not known. some problems that could be expected to occur with bacterially produced antigens are that the immunogenic site may not be properly exposed or the peptide sequence(s) within that site may not be able to form into the correct configuration. ...19836322643
protective role of foot-and-mouth disease virus antibody in vitro and in vivo in guinea-pigs. 19836834003
herpes type 2 infection with unusual generalised manifestations and delayed diagnosis in an adult male.a case of severe generalised herpes simplex type 2 infection is described in an adult male who had known exposure to herpes. the patient first complained of headache, fever and neurological symptoms, and three to six days later of conjunctivitis, severe pharyngitis, arthralgia and vesicular lesions about the body. during the first 14 days of illness, including three in hospital, the patient was diagnosed as having infection with varicella virus, vesicular stomatitis virus, or hand-foot-and-mouth ...19836875292
transformation and foot and mouth disease virus (fmdv) productivity of some bhk cell lines. 19836140842
the detection and inhibition of proteolytic enzyme activity in concentrated preparations of inactivated foot-and-mouth disease virus.proteolytic enzyme activity was detected in a large number of concentrated preparations of inactivated foot-and-mouth disease virus. several lines of evidence indicated that at least some of this activity could be attributed to bhk cells, although low levels of microbial contamination in many of our preparations could not be discounted and would certainly enhance the cellular proteolytic activity. from an experiment with different concentrations of trypsin, it was concluded that the proteolytic ...19836300129
physicochemical transformation of milk components and release of foot-and-mouth disease virus.possible mechanisms for protective roles of milk components on foot-and-mouth disease virus present in the milk of infected cows were examined. light scattering bands collected from ficoll-sucrose gradient fractions of skim-milk contained membrane-limited structures but these were non-infectious for bovine kidney cells. infectivity titres in buttermilk higher than those of the original cream or butter suggested association of virus with milk fat globules. increased infectivity titres in skim-mil ...19836302144
mode of penetration and intracellular localization of incoming parental foot and mouth disease virus (fmdv) in bhk cells.the process of penetration and subsequent early stages of replication of foot and mouth disease virus (fmdv) in bhk21 cell cultures have been studied in order to obtain further data about the infectious cycle of this virus. results suggest that fmdv penetrates bhk21 cells by way of pinocytic vesicles. studies of lysosomal (lf) and supernatant (sf) fractions of homogenized suspension of infected cells were carried out to learn the percentage of possible non-specific absorption of infectious virus ...19836302446
identification of amino acid and nucleotide sequence of the foot-and-mouth disease virus rna polymerase.foot-and-mouth disease virus (fmdv) rna polymerase was purified from the polyethylene glycol (peg)-treated supernatant of infected cell media by a combination of ion-exchange chromatography, membrane molecular filtration, and affinity chromatography. the purified rna polymerase which migrated as a single band of 56,000 molecular weight on a polyacrylamide gel was subjected to automated edman degradation and the sequence of the first 30 amino acid residues established. on the basis of previous ev ...19836305004
multiple homologies of oligonucleotide size exist between nucleic acids of picornaviruses.a semi-quantitative analysis of hybrid formation between restriction enzyme-generated subgenomic fragments of cloned cdna prepared from rna of foot-and-mouth disease virus (fmdv) strain o1k and radiolabelled rna from bovine enterovirus, bovine rhinovirus or mengo virus indicated that the hybrids were of oligonucleotide size. they were located in those parts of the fmdv o1k genome that code for the two capsid proteins vp3 and vp1 and the precursor protein p52 as well as at the 3' end. no hybridiz ...19836306155
an attempt at preparing anti-foot-and-mouth disease virus serum. 19836306318
point mutations in polypeptide vp1 of foot-and-mouth disease virus affect mouse virulence and bhk21 cell pathogenicity.virus produced in the first four days after infection of a bhk21 culture was shown to differ from that produced later in the infection. the early virus caused large plaques in ib-rs-2 cell sheets, had a slow cytopathic effect in bhk21 cultures and showed a high virulence for suckling mice. in contrast, the late virus caused small plaques, was rapid in its cytopathic effect and was of low virulence for mice. comparison between one clone each of the early and late virus showed that no change in im ...19836307221
[differentiation of foot-and-mouth disease viruses by an enzyme-bound immunosorbent micromethod (elisa)].fixed were the optimal conditions for the employment of the elisa method. the latter was successfully applied to differentiate and study the foot-and-mouth disease viruses. it was found that elisa was almost fifty times more sensitive as against the passive hemagglutination test, and almost one-hundred times more sensitive than the complement-fixation test. the results were found to correlate fully in the investigation of f. m. d. viruses of various origin with the use of the diagnostic methods ...19836308884
the improvement and standardization of the simplified process for the production of foot and mouth disease virus from bhk suspension cells.improvements have been made to the methodology for the production of foot and mouth disease (fmd) virus from bhk 21 clone 13 suspension cells by the simplified process. data derived from some 600 individual 8-1 cultures covering all seven types of fmd virus has been analysed. the production of virus was shown to (1) have no direct relationship to cell passage level and (2) to be inversely related to the cell multiplication factor observed during the cell growth cycle immediately prior to infecti ...19836309847
hybridoma cell lines secreting monoclonal antibodies against foot-and-mouth disease virus. 1. cell culturing requirements.the production of hybridoma cell lines secreting antibody against foot-and-mouth disease virus (fmdv) was more difficult than the production of similar cell lines secreting antibody against vesicular stomatitis virus or measles virus. a rapid and efficient protocol for the selection and culturing of 'anti-fmdv' hybridoma cultures was therefore developed and is described. this required the determination of the optimal culture medium (commercially available), source of serum supplement, line of my ...19836309848
hybridoma cell lines secreting monoclonal antibodies against foot-and-mouth disease virus (fmdv). ii. cloning conditions.three methods of cloning hybridoma cells--picking colonies from the masterplate, limit dilution cloning, and cloning in semi-solid medium over macrophage (m phi) feeder layers--were compared. cloning in semi-solid medium was found to be the most efficient and reliable, especially with our relatively slow growing anti-foot-and-mouth disease virus (fmdv) antibody secreting hybridoma cells. the optimum culture dish for this cloning was the 6-well (6w) dish (well diameter 1.5 cm), while the optimum ...19836309849
an investigation into causes of resistance of a cloned line of bhk cells to a strain of foot-and-mouth disease virus.the reduced ability of foot-and-mouth disease virus (fmdv) strain asia 1 iran 1/73 to replicate in the cloned bhk cell line aa7 was not due to lack of virus attachment at the cell surface. instead, the main restriction in the viral growth cycle occurred during synthesis and processing of viral macromolecules, and/or during the earliest stages of their assembly. reduced efficiency of penetration and uncoating of virus attached to the cells may also have contributed to inhibition of virus replicat ...19836310850
multiple genetic variants arise in the course of replication of foot-and-mouth disease virus in cell culture.the genetic heterogeneity generated upon passage of foot-and-mouth disease virus (fmdv) in cell culture has been evaluated by t1-oligonucleotide fingerprinting of genomic rna. plaque-purified fmdv o-s7 and c-s8 were propagated by serial low multiplicity infections of bhk-21 (c-13) or ibrs-2 (c-26) cells. in independent parallel passage of the same virus, different oligonucleotide variations were fixed in the rnas. t1-oligonucleotide fingerprinting of rna from 34 individual viral clones derived f ...19836310859
molecular cloning of cdna from foot-and-mouth disease virus c1-santa pau (c-s8). sequence of protein-vp1-coding segment.cdna segments copied from the rna of foot-and-mouth disease virus (fmdv) c1-santa pau (isolate c-s8) have been cloned in plasmid pbr322. a 998-bp dna fragment, that includes the region coding for capsid protein vp1, the carboxy terminus of vp3, and the amino terminus of precursor protein p52 has been sequenced. comparison of the nucleotide sequence with those from fmdv o1k, a(10)61, a12 and c3 indaial (kurz et al., nucl. acids res. 9 (1981) 1919-1931; kleid et al., science 214 (1981) 1125-1129; ...19836311686
histological and histochemical characterisation of mammary gland tissue of cows infected with foot-and-mouth disease by contact exposure.foot-and-mouth disease virus was observed to replicate in secretory epithelial cells of bovine mammary gland alveoli as a result of systemic infection initiated by exposure to infected animals. viral antigens were demonstrated using fluorescent antibody and immunoperoxidase labelling techniques before the development of signs of clinical disease. in addition, labelled antigens were observed associated with cytoplasmic-like fragments in luminal membrane limited structures. histologically, lesions ...19836312518
[passive hemagglutination reaction in differentiating foot-and-mouth disease viruses].experiments were carried out with the use of the passive hamagglutination reaction in the differentiation of foot-and-mouth disease viruses. the investigations made use of purified sera and specific igg antibodies obtained through column chromatography. conjugates were prepared with the use of bis-diazotized benzidine and glutaraldehyde. in experiments with conjugates prepared with igg and glutaraldehyde standard and reproducible results were obtained. the use of the passive hemagglutination tes ...19836312672
cross antigenicity among enteroviruses as revealed by immunoblot technique.antigenic relationships of various human and two animal picornaviruses were investigated by the immunoblotting ("western blot") technique. the viruses included all coxsackievirus b types (1-6), poliovirus types 1-3, several strains of echovirus 11, emc virus, and fmdv. antisera included human sera and sera from rabbits hyperimmunized with either purified picornaviruses, viral structural polypeptides (vp8), boiled or "sample-boiled" virions. group-specific reactions of various extent were observe ...19836312682
association of foot-and-mouth disease virus induced rna polymerase with host cell organelles.the localization of foot-and-mouth disease viral-induced rna polymerase has been determined in situ and in partially fractionated cell components by using polymerase antisera tagged with either peroxidase or ferritin. electron microscopic examination revealed the polymerase to be heavily concentrated on membranes of the smooth membranous vacuoles (smv) which are newly formed during infection and which were previously shown to be the site where newly synthesized viral rna appeared. polymerase ant ...19836313290
gene fusions using the ompa gene coding for a major outer-membrane protein of escherichia coli has been shown previously that fragments of the escherichia coli major outer membrane protein ompa lacking co2h-terminal parts can be incorporated into this membrane in vivo [bremer et al. (1982) eur. j. biochem. 122, 223-231]. the possibility that these fragments can be used, via gene fusions, as vehicles to transport other proteins to the outer membrane has been investigated. to test whether fragments of a certain size were optimal for this purpose a set of plasmids was prepared encoding 16 ...19836313361
the attachment of the foot-and-mouth disease virus asia i iran 1/73 to bhk suspension cells does not require virus specific cell receptors.experiments are described which show that a member of the picornaviridae (fmd virus asia i iran 1/73) attaches to bhk suspension cells in a manner which precludes a requirement for virus specific receptors on the cell plasma membrane. while it may be possible to demonstrate the apparent saturation of the cell surface with multiple doses of virus, an increase of the concentration of the dosing suspension results in more virus attachment. indeed, it was found that with the amounts of virus which w ...19836314941
innocuity testing of foot-and-mouth disease vaccines. ii. aziridine-inactivated antigen produced in baby hamster kidney cells.methods for the testing of preparations of aziridine-inactivated foot-and-mouth disease virus for the absence of infective particles were studied. the system used for virus production, suspension cultures of baby hamster kidney cells, proved to be the most sensitive detection system for traces of infective virus as long as the 146s antigen concentration was below 1 microgram per 10(6) cells. above this level interference may mask the presence of non-inactivated virus. thus in a 1-1 suspension cu ...19836315737
aerosol exposure of cattle to foot-and-mouth disease virus.slight modifications of a small, plastic covered greenhouse provided a chamber for the exposure of cattle of all ages to aerosols of foot-and-mouth disease virus. particle size distributions of aerosols were 76% less than 3 microns, 17% 3-6 microns, and 7% greater than 6 microns immediately after the devilbis no. 40 nebulizer used was turned off and 90% less than 3 microns, 8% 3-6 microns, and 2% greater than 6 microns 20-30 min later. pharyngeal virus growth curves and viremia patterns correlat ...19836315813
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