Publications

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.		1982	6287702
portraits of viruses: foot-and-mouth disease virus.		1982	6288615
the elution of foot-and-mouth disease virus from vaccines adjuvanted with aluminium hydroxide and with saponin.		1982	6290497
susceptibility of squirrel and cebus monkeys to foot-and-mouth disease virus.		1982	6290662
a novel structure seen when foot-and-mouth disease virus-induced poly (u) polymerase acts in a cell-free system.		1982	6290687
serological analysis of recent type o foot-and-mouth disease virus isolates from europe.		1982	6291221
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 ...	1982	6292127
concentration of foot-and-mouth disease virus in milk of cows infected under simulated field conditions.		1982	6292275
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 ...	1982	6292352
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 ...	1982	6292355
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 ...	1982	6284093
antibody titres to african horse sickness, swine vesicular disease and foot-and-mouth disease viruses in samples from equidae in malta, 1975.		1982	6284298
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 ...	1982	6284329
interactions between saponin and 146s particles of foot-and-mouth disease virus.		1982	6284760
qualitative assessment of 146 s particles of foot-and-mouth disease virus in preparations destined for vaccines.		1982	6284761
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 ...	1982	6284836
comparative immunogenicity of 146s, 75s and 12s particles of foot-and-mouth disease virus.		1982	6293410
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 ...	1982	6294327
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 ...	1982	6294604
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 ...	1982	6296284
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 ...	1982	6296955
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 ...	1982	6297430
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 ...	1982	6176678
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 ...	1982	6179141
synthesis of long dna molecules complementary to foot-and-mouth disease virus rna.		1982	6181010
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" ...	1982	6186225
[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 ...	1982	6101001
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.	1982	6203738
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 ...	1981	6169797
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 ...	1981	6176487
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.	1981	6257779
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 ...	1981	6261157
isolation of a soluble and template-dependent foot-and-mouth disease virus rna polymerase.		1981	6263001
visualization by chilling of protein bands in polyacrylamide gels containing 8 m urea: preparation and quantitation of foot-and-mouth disease virus capsid proteins.		1981	6263128
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 ...	1981	6264400
differential precipitation of foot and mouth disease virus proteins made in vivo and in vitro by hyperimmune and virus particle guinea pig antisera.		1981	6264693
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.	1981	6112866
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.	1981	6112867
[molecular biology of the foot-and-mouth disease virus].		1981	6285123
[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 ...	1981	6283723
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 ...	1981	6280815
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 storage.	in 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 ...	1981	6281108
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 ...	1981	6281109
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 ...	1981	6267181
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 ...	1981	6268821
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 ...	1981	6268834
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 ...	1981	6270249
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 ...	1981	6270678
heterogeneity of infection-associated particles in foot-and-mouth disease virus.		1981	6270879
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 ...	1981	6271913
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 ...	1981	6272395
[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 ...	1981	6272473
production in b. subtilis of hepatitis b core antigen and a major antigen of foot and mouth disease virus.		1981	6273732
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 ...	1981	6275123
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 ...	1981	6277281
relationship between plaque size and the immunising ability of the foot-and-mouth disease virus sat 1 nig 10/75.		1981	6277283
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 ...	1981	6258084
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 ...	1980	6260578
[immune response in guinea pigs to foot-and-mouth disease virus. study of the biological activities of igg subclasses in hyperimmunized animal sera].		1980	6292997
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 ...	1980	7400424
[enzymatic synthesis and properties of dna, complementary to foot and mouth disease virus rna].	the rnas of the aphthosa virus, serotypes a and o were isolated and characterized. the complementary dnas used in experiments on molecular hybridization with matrix rnas were synthesized on virion rnas by means of reverse transcriptase.	1980	6165404
sites of release of airborne foot-and-mouth disease virus from infected pigs.	pigs infected with foot-and-mouth disease virus by different routes of exposure were air-sampled individually, first as 'intact' (i-) pigs and then as 'intubated' (t-) pigs, using an endotracheal tube. irrespective of the route of infection it was found that during the early stages of disease more virus was recovered from i-pigs than from t-pigs. most of the virus from i-pigs during incubation and early disease was associated with large and medium sized particles. t-pigs infected by direct or in ...	1980	6265993
[laboratory trials of culturing bhk 21 c 13 cells in a roller using an enzymatic egg hydrolysate-based nutrient medium].	experiments were carried out to find the optimal conditions for the replication of bhk 21 c 13 cells in one 1 roller glassware with the use of a nutrient medium containing products of the enzymatic breakdown of white of egg. studied was the sensitivity of these cells to the type c strain 'hungary' of the foot-and-mouth disease virus. two series of f. m. d. vaccines were produced, which proved to be sterile and innocuous for guinea pigs. immunogenicity trials with regard to these animals revealed ...	1980	6266126
serological and immunological relations between the 146s and 12s particles of foot-and-mouth disease virus.	intact 146s particles of the seven serotypes of foot-and-mouth disease virus (fmdv) produce type-specific precipitating, complement-fixing and neutralizing antibodies in cattle and guinea-pigs. however, the 12s structural subunit, produced from the virus particle by mild acid treatment (ph 6) or by heating at 56 degrees c, although stimulating the production of precipitating and complement-fixing antibodies, produces only low levels of neutralizing antibody. nevertheless, 12s antibody in guinea- ...	1980	6257825
a study of the level of nucleotide sequence conservation between the rnas of two types serotypes of foot-and-mouth disease virus.	the level of nucleotide sequence conservation between the rnas of type a and type o foot-and-mouth disease virus (fmdv) has been compared by three methods. (i) rna hybridization of fragments containing either the poly(c) tract at the 5' end of the rna of the poly(a) tract at the 3' end of the rna indicates that there is a similar level of sequence conservation (65% homology) across the genome. rnase t1 fingerprinting of these fragments did not show the presence of any long regions of completely ...	1980	6257826
a study of the cross-reacting antigens on the intact foot-and-mouth disease virus and its 12s subunits with antisera against the structural proteins.	cross-reactions between two strains of foot-and-mouth disease virus (fmdv) belonging to different serotypes (a and o) were studied with intact virus and virus subunits and antisera produced against the isolated structural proteins. anti-vp1 type o serum showed cross-reactive neutralizing activity, in contrast to the sera raised against intact virus type o, whereas anti-vp1 type a serum only neutralized homologous virus. anti-vp2, vp3 and vp4 did not show neutralizing activity. in the enzyme-link ...	1980	6257830
comparison of the nucleotide sequence at the 5' end of rnas from nine aphthoviruses, including representatives of the seven serotypes.	the sequence of about 70 nucleotides at the 5' end of the rnas of nine different aphthoviruses (foot-and-mouth disease viruses), including representatives of the seven serotypes of the virus, has been determined by partial enzyme digestion of (32)p-end-labeled s fragment-that part of the rna lying to the 5' side of the poly(c) tract and including the 5' end of the molecule. the s fragments were prepared from polyadenylated virus-specific rna extracted from infected cells by digestion with rnase ...	1980	6257918
biochemical aspects of variation in foot-and-mouth disease virus.	the biochemical basis for variation in foot-and-mouth disease virus (fmdv) has been explored by analysis of the virus rna and the virus-induced and structural proteins of three isolates of the virus. two of the isolates were from serotype a and the third was from serotype o. hybridization studies of the rnas showed greater than 80% homology between the two type a viruses and about 65% homology between the two type a viruses and the virus of type o. the ribonuclease t1 maps of the three viruses g ...	1980	6243341
characterization of a foot-and-mouth disease mutant temperature-sensitive for viral rna synthesis.	a temperature-sensitive (ts) mutant of foot-and-mouth disease virus (fmdv) did not produce rna polymerase activity nor synthesize viral rna when incubated in cells solely at the nonpermissive temperature (38.5 degrees c). infected cells initially incubated at 38.5 degrees c and then shifted down to 33 degrees c synthesized increased amounts of viral rna at earlier times compared to infected cells kept at 33 degrees c throughout, indicating that rna polymerase precursors were synthesized at 38.5 ...	1980	6243922
aspects of heat inactivation of foot-and-mouth disease virus in milk from intramammarily infected susceptible cows.	in skim milk obtained from susceptible cows after intramammary and intravenous inoculation (primary infected milk), foot-and-mouth disease (fmd) virus type o1 was slower inactivated by heat treatment than virus that had been added to pre-exposure skim milk. residual virus infectivity in heated primary infected milk was more efficiently detected in bovine thyroid cell cultures than in secondary pig kidney (pk2) cell cultures. untreated primary infected milk was found to inhibit both fmd-virus and ...	1980	6244342
foot-and-mouth disease virus production in glass sphere based monolayer systems of 0.1 to 100 l medium volume.	the cell and virus productivity of a 3 mm glass sphere based unit process monolayer system was determined at scales of 0.1, 1, 10 and 100 litres medium capacity. enhanced yields were obtained up to the 10l size when compared with control roux bottle cultures. modifications of the operating conditions of the 100l system should bring this into line with the smaller-scale units.	1980	6244996
the potential of recombination for the production of foot-and-mouth disease virus vaccine strains.	biological proof of recombination in foot-and-mouth disease virus has been provided by studies on a large suite of conditional lethal mutants and a recombination map of approximately 70 mutations has been produced. however, recombination is a highly variable phenomenon and this has cast doubt on its validity and certainly on its applicability to such practical purposes as the production of good vaccine strains. evidence is presented to demonstrate (1) that the genetic map has a good correlation ...	1980	6244999
foot and mouth disease virus production on microcarrier-grown cells.	the industrial usefulness of the production of foot and mouth disease virus with microcarrier grown cells has been tested at a large scale. the vaccines, intended for pigs, prepared with such virus give a good level of immunity against virulent challenges. they are stable and free from side effects.	1980	6245001
location of the initiation site for protein synthesis on foot-and-mouth disease virus rna by in vitro translation of defined fragments of the rna.	an mrna-dependent reticulocyte lysate has been used to translate foot-and-mouth disease virus rna in vitro. polypeptides p16, p20a, and p88, which have been shown to be derived from the 5' end of the rna by pactamycin mapping experiments with infected cells, were preferentially synthesized in vitro. removal of vpg, the small protein covalently linked to the 5' end of the genome rna, had no effect on the translation of the rna. the two rna fragments (l and s) produced by specific digestion of the ...	1980	6245254
variation in the susceptibility of bhk populations and cloned cell lines to three strains of foot-and-mouth disease virus.	bhk monolayer and suspension cell populations maintained in different laboratories were found to vary in their susceptibility to infection with three strains of foot-and-mouth disease virus (fmdv). the susceptibility of parent cell populations was compared with that of individual clones of cells derived from them. the populations tested in this way consisted of a number of cell types, each expressing a different capacity to produce fmdv. the relative numbers of susceptible and insusceptible cell ...	1980	6245630
structural proteins of hand, foot and mouth disease viruses.	coxsackievirus a16 (ca16) and enterovirus 71 (e71), which cause hand, foot and mouth disease, were compared with respect to their polypeptide composition by page. only three proteins were resolved for ca16, whereas the four characteristic structural proteins of e71, (vp1, vp2, vp3 and vp4) were separated. the distribution of labeled proteins suggested that the molecular weights of vp2 and vp3 of ca16 were very similar. the smallest protein, vp4, of ca16 and e71 had the same molecular weight, but ...	1980	6246027
temperature-sensitive mutants of foot-and-mouth disease virus with altered structural polypeptides. i. identification by electrofocusing.	the structural polypeptides of foot-and-mouth disease virus were analyzed by electrofocusing in a polyacrylamide gel containing 9 m urea. three versions of the technique were used to accomodate the widely differing isoelectric points of the four polypeptides. vp2 was identified by comparing mature virus with procapsids. the selective actions of proteases on virions of two serotypes and on their 12s particles were examined. from this emerged a simple test for distinguishing the similarly sized po ...	1980	6246262
temperature-sensitive mutants of foot-and-mouth disease virus with altered structural polypeptides. ii. comparison of recombination and biochemical maps.	the structural polypeptides of foot-and-mouth disease virus were digested with staphylococcus aureus v8 protease in the presence of sodium dodecyl sulfate. the protease-resistant peptides derived from temperature-sensitive mutants were compared with those of the wild type by electrofocusing in a polyacrylamide gel. covariation between the charge shifts of different peptides indicated that they shared common sequences: only five independent peptides in all were derived from vp1, vp2, and vp3, acc ...	1980	6246263
the application of a single radial haemolysis technique to foot-and-mouth disease virus-antibody study.	experiments are described for the evaluation of the single radial haemolysis (srh) technique applied to fmd virus, using a method involving the coupling of either antigen or antibody to sheep erythrocytes. the antigen coupling method detected specific antibody but the technique was found to be impractical as it gave reproducible results only with purified virions. however, the antibody coupling technique gave clear zones of lysis using tissue culture harvest virus as well as purified virus, and ...	1980	6246855
heterogeneity of the genome-linked protein of foot-and-mouth disease virus.	the genome-linked protein of foot-and-mouth disease virus was examined by electrofocusing in polyacrylamide gels. two proteins of different charge and amino acid composition were found. the tryptic peptide maps of the proteins were dissimilar. the possible relationship between the two proteins is discussed.	1980	6247501
[the rotating aeration (system fuchs) for treatment of liquid animal and municipal wastes. 8. the effect of aerobic treatment of foot and mouth disease virus].		1980	6248023
early interactions of foot-and-mouth disease virus with cultured cells.		1980	6249029
detection of antibodies against foot-and-mouth disease virus using purified staphylococcus a protein conjugated with alkaline phosphatase.	purified protein a (pa) from staphylococcus aureus was conjugated with the enzyme alkaline phosphatase. this reagent reacted well with pig, rabbit and guinea pig igg and less well with mouse and bovine igg. radioactive 125i-labelled pa showed a similar affinity for the iggs examined. antibodies against foot-and-mouth disease virus contained in guinea pig, rabbit and pig serum were detected, using the enzyme-conjugated pa in indirect tests, which were of similar sensitivity to those using enzyme- ...	1980	6249867
isolation of a foot-and-mouth disease polyuridylic acid polymerase and its inhibition by antibody.	a template-dependent polyuridylic acid [poly(u)] polymerase has been isolated from bhk cells infected with foot-and-mouth disease virus (fmdv). enzyme activity in a 20,000 x g supernatant of a cytoplasmic extract was concentrated by precipitation with 30 to 50% saturated ammonium sulfate. the poly(u) polymerase was freed of membranes by sodium dodecyl sulfate and 1,1,2-trichlorotrifluoroethane extraction, and rna was removed by precipitation with 2 m licl. the solubilized poly(u) polymerase requ ...	1980	6251248
some virus diseases of domestic animals in the sultanate of oman.	little is known of the occurrence of animal virus diseases in the sultanate of oman. this paper reports the results of a countrywide survey carried out in 1978 to establish the prevalence of some important viral pathogens of domestic animals with the dual purpose of providing baselines for future investigations and guidelines for those entrusted with disease control. foot-and-mouth disease virus type o, previously identified in oman in 1976, was isolated from clinically affected animals. in addi ...	1980	6251586
foot and mouth disease virus. properties of a clone selected by terminal dilution technique from the original population.	using the terminal dilution technique, a cloned virus was selected in a tissue culture systems from a heterogenous population of the original virus. the different markers studied differentiated the cloned virus from the original virus on the basis of its following characters: 1. ability to grow more efficiently at 29 than at 37 degrees c. 2. unstability of its capsid as seen by: a. high degree of sensitivity to heating at 50 degrees c for 10 min of exposure to ph 6.4 for 10 min. b. more inactiva ...	1980	6254429
morphogenesis of vesiculation in foot-and-mouth disease.	the morphogenesis of vesiculation in cattle inoculated (aerosol expsoure) with foot-and-mouth disease virus was investigated by examining alternate, frozen sections of selected tissues stained by fluorescent antibody technique and with hematoxylin and eosin. viremia preceded the development of lesions, and virus appeared to be transported to the epithelium via papillae. lesions were initiated usually by the infection of single cells in the stratum spinosum adjacent to the papillae. three types o ...	1980	6255841
stability and immunogenicity of empty particles of foot-and-mouth disease virus.	three strains of foot-and-mouth disease virus were shown to contain significant amounts of naturally occurring 75s, empty particles as well as the infectious, 140s full particles. one of these strains--a pando (1970)--was studied in detail. the empty particles from this virus strain were shown to have an observed sedimentation coefficient of 67s in 0.04 m phosphate buffer; they were labile in sds, non-infectious and probably rna-free and, on heating, they broke down to 12s subunits as did the 14 ...	1979	218538
relationship between virus neutralization and serum protection bioassays for igg and igm antibodies to foot-and-mouth disease virus.	the time interval between administering the serum and the virus was found to influence the results of the in vivo mouse protection test for foot-and-mouth disease antibodies. in particular, for both igg and igm antibodies to strain a12 virus, the mouse protection index increased from zero to a maximum at about 6 h and remained high for at least five days. variations in the antiserum concentration, on a log scale, had a proportional effect on the mouse protection index, if between 1 and 3. the co ...	1979	219135
detection and quantification of foot and mouth disease virus by enzyme labelled immunosorbent assay techniques.	enzyme labelled immunosorbent assays (elisa) have been developed to detect and quantify foot and mouth disease (fmd) virus using flexible plastic microtitre plates. the methods were successful for the specific detection of fmd virus and were 50 to 100 times more sensitive than the complement fixation test. the application of the elisa techniques to fmd virus typing and subtyping, and to the assay of antigen concentration during manufacture of vaccines is discussed.	1979	219137
the specific detection of foot-and-mouth disease virus whole particle antigen (140s) by enzyme labelled immunosorbent assay.	a solid-phase micro-enzyme-labelled immunosorbent assay (elisa) using guinea pig antiserum against purified (140s) inactivated foot-and-mouth disease (fmd) virus has been used in a sandwich technique to specifically measure 140s virus in the presence of 12s material.	1979	222837
sequence and location of the poly c tract in aphtho- and cardiovirus rna.	the poly c tract in the rna of the aphtho- and cardio viruses has been examined in several isolates of foot-and-mouth disease virus (fmdv) and encephalomyocarditis (emc) virus. the length of the tract is variable, containing 100 to 170 bases in the fmdv isolates and 80 to 250 bases in the emc virus isolates. each poly c tract contains c. 10% a and u residues, located at the 5' end, i.e. most of the tract is a continuous run of c residues. the position of the tract on the genome was the same in e ...	1979	223128
development of a methodology for the production of foot- and- mouth disease virus from bhk21 c13 monolayer cells grown in a 100 l (20 m2) glass sphere propagator.		1979	223915
cell culture on beads used for the industrial production of foot-and-mouth disease virus.	the microcarrier culture technique has been applied to a pig kidney cell line. microcarriers consisted of deae sephadex a 50 beads washed and containing carboxymethyl cellulose. sifted beads gave better results than unclassified material. cells for inoculum were prepared in roux flasks. the two types of fermentors which were used (operating capacity 100 l and 150 l) gave similar results. the growth of the cells can easily be followed by microscopic observation and cell count. the yields of cells ...	1979	223917
the use of frozen bhk21 c13 cells to control the biological parameters for cell and foot-and-mouth disease virus growth.	in order to control the four primary variables (cells, serum, medium and physical conditions) in a cell or virus growth system it is important to have a reliable and constant positive control with which to compare any variable of the system components. the use of aliquots of a frozen cell population (stored at -136 degrees c) for this purpose is the subject of this paper. using such cells, tests have been established for the control of sera, media, cell susceptibility and the quality of serum tr ...	1979	223922
some aspects of fmdv-production in growing cells and a closed system for concentration of fmdv by polyethylene glycol.	different commercially available peptone preparations, all derived by enzymatic digestion of meat, were tested for their ability to replace the individual amino acids and polyethylene glycol (peg)-treated serum in bhk suspended cell culture growth medium. cell growth was not impaired if the individual amino acids were replaced by 3 g/l of peptone in combination with 3 g/l lah and 5% peg-treated bovine serum. the concentration of the latter could be reduced to 1% by gradually lowering the concent ...	1979	223924
immunity to foot-and-mouth disease virus in guinea pigs: clinical and immune responses.	clinical and immune responses were determined for guinea pigs infected with different doses of foot-and-mouth disease virus (fmdv) type a12, strain 119, administered by different routes. vesicles developed on the tongue or heel pad 1 day after these areas were intradermally inoculated with fmdv. however, vesicles did not develop on the feet and tongue until 3 to 4 days after the intradermal inoculation of fmdv in the flank skin or after intracardiac or subcutaneous inoculation. infected guinea p ...	1979	223986
isolation and characterization of trypsin-resistant o1 variants of foot-and-mouth disease virus.	strains of foot-and-mouth disease virus of types o1 and a10 were isolated which showed no significant loss of infectivity upon trypsinization. these 'trypsin-resistant' (tr) viruses were obtained by serial passage in bhk cells of virus that was trypsin-treated before inoculation of the cells. three o1 isolates were cloned and studied further. cell attachment of those tr o1 variants (otr1) was not reduced by trypsinization, unlike that of parent virus. the polypeptide compositions of tr viruses a ...	1979	225425
morphogenesis of foot-and-mouth disease virus. i. role of procapsids as virion precursors.	the role of procapsids during foot-and-mouth disease virus multiplication was studied on infected bhk-21 cells. purified virus and procapsids were obtained by treating the infected cytoplasmic extracts with rnase and edta. the synthesis of virus, procapsids, and total particles was determined in pulse-chase experiments. a precursor-product relationship between procapsids and virions was obtained. the results show that the rate of synthesis of total particles (virus + procapsids) was linear from ...	1979	225534
antibody response against foot and mouth disease virus (fmdv). part i: responses measured in sera of vaccinated steers with complete virus, trypsin treated virus, 12 s virus subunits and heterologous virus.		1979	225907