Publications

[comparison of the immunogenic potencies of purified inactivated foot-and-mouth disease virus particles with variable amounts of vp1 protein (author's transl)].		1977	195512
determination of the time to harvest foot-and-mouth disease virus cultures by measurements of the supernatant concentration of lactic dehydrogenase.		1977	195645
evidence for a mouse pathogenicity locus in certain temperature-sensitive mutants of foot-and-mouth disease virus.	serial tissue culture passaging of three foot-and-mouth disease temperature-sensitive mutants demonstrated the stability of their temperature sensitivity and mouse avirulence characteristics. recovery of mouse-virulent temperature-sensitive viruses after passage of the mutants in mice suggested that these were not covariant expressions of the same locus, but were under the control of different genes.	1977	197007
protein covalently linked to foot-and-mouth disease virus rna.		1977	197422
modeling and computer stimulation approach to the mechanism of foot-and-mouth disease virus neutralization assays.	block neutralization data since 1949 for the foot-and-mouth disease virus system have been analyzed in terms of a unified mass-action theory for computing the amounts of infectious complexes. proof that infectious complexes contribute considerably to the assays was obtained by demonstrating a reduction in titer after an additional reaction with anti-ig antibody before the assay. in the suckling-mice assay with intraperitoneal inoculation, both the data of others and our own on several types indi ...	1977	197591
[basic moments in the interactions between the foot-and-mouth disease virus and cells in cell cultures].		1977	197687
subtyping of foot-and-mouth disease virus.		1976	198283
[serological study of several strains of foot-and-mouth disease virus type "o" isolated in europe between 1971 and 1975: application of the biomathematical system of classification].	nine strains of foot-and-mouth disease virus type "o" received in our laboratories since 1971 have been studied serologically by osler's quantitative method of complement fixation (50% hemolysis). the results, submitted to the biomathematical system of bidimensional classification, allow to conclude that at present in europe there are two groups of foot-and-mouth disease strains of type "o"; one has reference to our vaccinal strain "o lausanne 1965" and the other to "o romania 1972" strain, whic ...	1976	198285
examination of differences between foot-and-mouth disease virus strains using a radioimmunoassay techinque.	a radioimmunoassay (ria) technique was used to compare different samples of type sat 2 foot-and-mouth disease (fmd) viruses. the reaction involved the measurement of the competition of heterologous virus with homologous virus for previously titrated homologous antiserum. the results showed that differences occurred between the viruses examined. viruses could be grouped according to their ability to compete with the homologous virus, and statistically significant differences between virus 'groups ...	1976	198286
[classification of strains of foot-and-mouth disease virus according to the relationship-dominance model for a better understanding of the concept of serologic and immunologic subtype].	the homologous and heterologous serological titers of a specific serum can be integrated in a bidimensional system which characterizes the criteria of relationship and dominace. this bidimensional classification specifies more precisely the serological properties of each strain compared with the others (taxonomic purpose) and allows eventual guidance in the choice of vaccinal strains (epizootiologic and prophylactic purposes).	1976	198287
serological differentiation of foot-and-mouth disease virus strains in relation to selection of suitable vaccine viruses.		1976	198288
antibody response of tropical range cattle to foot-and-mouth disease virus. ii. evaluation of response to o-1, a-27, and a-18 subtypes.		1976	198289
new media and their advantages in the production of suspended cells and foot--and--mouth disease virus.	the problems related to the use of serum in cell culture are reviewed. the possibility of substituting the serum with peptones has already been shown. different peptones have been tested: one of the best is a peptone obtained from meat and casein pepsin pancreatically digested. bhk 21/13 cells were cultivated in serum-free media for 35 passages. the 0.81 cultures without automatic ph control had a cycle length of 3 days; starting with concentrations of 0.4 x 10(6) cells/ml, concentrations higher ...	1976	198293
[routine physico-chemical testing of concentrated virulent and inactivated foot-and-mouth disease virus antigens].	the ponderal quantity of 140 s antigens and their peptide distribution are controlled in concentrated virulent and inactivated preparations proir to their being transformed into vaccines. a certain variability in the amount of 140 s particles and in the titer of peptide sensitive to trypsin (vp1) has been demonstrated in the virulent preparations. after treatment by inactivating agents (glycidaldehyde, binary ethyleneimine and formaldehyde) two types of alteration of the viral capsid are shown : ...	1976	198300
[immunogenic quality of foot-and-mouth disease virus].	routine analysis of suspensions of foot-and-mouth disease virus and eluates of vaccine by the isopycnic method in analytical ultracentrifuge demonstrates the important heterogeneity of the viral population. this heterogeneity increases during inactivation of the virus by formol. in view of this dispersion of the physical characteristics of viral particles it may be asked (a) whether the immunogenic value is linked to the total quantity of particles which, we know, are very different from each ot ...	1976	198301
an evalutation of some methods of assay of foot-and-mouth disease antigen for vaccines.	the relative merits of various in vitro assay systems for the measurement of the quality and quantity of foot-and-mouth disease virus vaccine antigen will be discussed. the assay systems include : viral infectivity, complement fixing activity, particle counts, radial diffusion titre and single radial haemolysis titre. the predictive value of the tests for the immunogenicity of the final vaccine product will be evaluated against the results of 50% protective dose titres determined in guinea pigs ...	1976	198302
comparison of laboratory techniques for the evaluation of the antigenic potency of foot-and-mouth disease virus cultures and vaccines.		1976	198304
antibody response of tropical range cattle to foot-and-mouth disease virus. i. comparison of three tests.		1976	198305
fast modification of foot-and-mouth disease virus by selecting clones in bovines.		1976	198313
certain aspects of foot--and--mouth disease. virus production in growing bhk suspended cell cultures.	production of fmdv in growing bhk suspended cell cultures offers several technical advantages: no medium change and no sedimentation of cells prior to infection are needed, thus saving time and medium. however, the final product should be as free of serum proteins as possible. for this purpose polyethylene-glycol-(peg)-treated serum can be used for the stimulation of cell growth in combination with precipitation of the virus with peg. with this method virus preparations are obtained in which pra ...	1976	198314
studies on the susceptibility to foot--and--mouth disease virus of bhk cell cultures derived from various sources.	cultures of bhk monolayer and suspension cells obtained from a number of laboratories and a group of cloned sub-lines derived from suspension cells were examined for their susceptibility to three fmd virus strains. it was found that the various cultures were sensitive to the test virus strains to differing degrees. it was shown possible to obtain a clone with high susceptibility to asia 1 iran 1/73 virus from a parent culture which had a low susceptibility to that virus. the implication of these ...	1976	198315
reproducibility of yields of foot--and--mouth disease virus from bhk monolayer and suspension cells.	the production of fmd virus from bhk 21 c13 monolayer and suspension cells was examined under standardized conditions and in different systems. the yields of virus from suspension cells did not significantly exceed the yield from monolayer cells, whereas the monolayer cell was capable of producing virus from some strains of fmd virus which would not grow in suspension cells. when different production systems were examined, the scale of operation did not significantly influence the yield of virus ...	1976	198316
[study of foot-and-mouth disease virus inhibitors in cell cultures and experimental animals].	studied was the inhibiting action of some synthetic agents conditionally denoted no. 3 (benzamidazol), no. 76, and no. 78 (imidazolins) on the reproduction of the foot-and-mouth disease virus in cell cultures, newborn mice and guinea pigs. it was irrefutably demonstrated that all three agents produce an inhibiting effect on the virus. this effect was enhanced by the combined use of these inhibitors. it was found that best effect on the virus' replication produced the combination of agent no. 3 a ...	1976	193238
[study of the immunity in swine vaccinated with type c anti-foot-and-mouth disease vaccine].	experiments were carried out to adapt a cell culture strain of the foot-and-mouth disease virus, type c, to the organism of susceptible pigs. it was established that 4 to 5 passages are needed to adapt the virus, all treated animals showing the symptoms of the disease from the 24 hour following infection which assumed a generalized course. in determining the index of protection (p) of a given f.m.d. vaccine through challenging immunized pigs its value proves to be 4.5. it is stressed that this i ...	1976	193242
unified mass-action theory for virus neutralization and radioimmunology.	all ideas implicit in the papers since 1953 involved in applying mass-action thermodynamics to antibody-antigen reactions are unified by the use of: (a) the intermediary concept of extent of reaction; (b) the concept of intrinsic association constant; (c) a statistical analysis for probable complexes; and (d) identification of the complex or complexes that contribute to the bioassay. several general theoretical examples are given that show the limitations of linear interpretations of equilibrium ...	1976	185688
susceptibility of a new fetal pig kidney cell line (mvpk-1) to foot-and-mouth disease virus.	the mengeling-vaughn porcine kidney (mvpk-1) cell line, derived in october, 1970, from fetal pig kidneys, is susceptible to all 7 types of foot-and-mouth disease (fmd) virus. a plaque assay was developed for fmd virus that depended on washing mvpk-1 cells in serum-free medium before infection and excluding serum from 0.6% gum tragacanth overlay during plaque formation. the numbers of plaques that formed on mvpk-1 cells by a representative strain of each fmd type were comparable with the numbers ...	1976	185927
routine titration of foot and mouth disease virus suspensions by analytical ultracentrifugation. 1: sedimentation method.	infectivity and complement fixation (cf) tests are commonly used for the routine titration of foot and mouth disease (fmd) virus suspensions. only recently were techniques published for the routine determination of the virus concentration by the physical properties of the virions (fayet et al., 1971; barteling et al., 1974). these techniques are based on the separation of the virions from the culture fluid by sedimentation through a sucrose gradient, in a preparative ultracentrifuge. the ultrav ...	1976	185978
[role of antibodies in the antigenic variability of the foot-and-mouth disease virus].		1976	186935
inhibitors of foot-and-mouth disease virus. temperature-dependence of the effect of guanidine on virus growth.	in suspended secondary calf kidney cells infected with foot-and-mouth disease virus (fmdv) the temperature range for optimal virus growth is shifted down by 3 to 5 degrees c in the presence of 1--2 mm guanidine. for some virus strains this shift is so effective that at infraoptimal temperatures virus yield in guanidine-treated cells exceeds that of the corresponding control by more than one log10. on the contrary, at supraoptimal temperatures inhibition of virus growth by the drug is strongly en ...	1976	187151
a foot-and-mouth disease vaccine for swine.	an inactivated vaccine containing purified foot-and-mouth disease virus type o1, strain brugge, emulsified with incomplete freund's adjuvant was studied in swine. the antigen mass ranged from 0.02 to 416 mug in 0.25 ml of vaccine. at 90 days postinoculation (dpi) 33 to 100% of the swine which had been inoculated with 0.72% mug or larger amounts of antigen were protected against challenge. there was little protection at 182 dpi although the neutralizing titers obtained with 2.9, 34.6 and 416 mug ...	1976	187292
the location of the ploy(c) tract in the rna of foot-and-mouth disease virus.	fragments of foot-and-mouth disease virus rna of decreasing size, containing the 3' poly(a) sequence have been prepared by alkali treatment and sucrose gradient centrifugation followed by oligo(dt)-cellulose affinity chromatography. polyacrylamide gel electrophoresis of the ribonuclease t1 resistant oligonucleotides from these polyadenylated fragments has enabled us to locate the position of some of the longer oligonucleotides on the rna. in particular the poly c tract has been shown to be near ...	1976	187724
typing foot-and-mouth disease virus by fluorescent antibody technique.	typing of foot-and-mouth disease (fmd) virus was performed by the direct fluorescent antibody (fa) technique. type-specific fa was prepared from the following two sorts of procedures: (1) fa against live virus (fa-live) was prepared from hyperimmune serum taken from guinea pigs having received live fmd virus. then it was adsorbed with concentrated heterotype antigen. (2) fa against inactivated virus (fa-inact) was prepared from antiserum taken from guinea pigs immunized with purified fmd virus i ...	1976	189221
[foot-and-mouth disease in ethiopia. serologic and immunologic study of type a foot-and-mouth disease virus].		1976	189363
[cultivation of the foot-and-mouth disease virus in various vnk-21 cell sublines].		1976	189481
[use of indirect complement fixation test for studying foot and mouth disease virus].	the indirect complement-fixation test was used in experiments for the subtype differentiation, and with the agar gel diffusion and the serum neutralization test was studied the immunity in cattle that had already recovered from foot-and-mouth disease or were immunized against the disease. it was found that the indirect complement-fixation test is instrumental in the demonstration of the antigenic differences between the foot-and-mouth viruses. comparative experiments have shown that the indirect ...	1976	189484
[attempts to adapt bnk cells to cultivation in suspension and study of the antigenic properties of foot-and-mouth diseases viruses obtained from them].	experiments were carried out to cultivate the foot-and-mouth disease virus under laboratory conditions in a suspension of the bhk-21 cell line. results showed that the number of cells cultivated in a susfor 48 to 72 hours of incubation reaches up to 2.2 x 10(6). it was also found that certain conditions should be observed for the successful cultivation of the cells in suspension, such as aeration, ph, and respective temperature. it was demonstrated that foot-and-mouth diseases viruses obtained f ...	1976	189487
[various physical and chemical properties of the 73s unit of the foot-and-mouth disease virus].	at all 3 studied fmd-viruses typs o2, a5 and c we could show the 73s unit in the analytical ultracentrifuge and in the electron microscope. 73s unit is found in the normal cycle of purification of virus and by density gradient centrifugation separated and purified. in cscl ph 7.6 its density is 1.308 +/- 0,005 g/ml. its sedimentation coefficient has a value of 72.7 +/- 1,5s. in electron microscope it show itself as a empty virus capsid. its diameter is in partial purified preparations with 25 +/ ...	1976	190967
cell-free translation of foot-and-mouth disease virus rna into identifiable non-capsid and capsid proteins.	foot-and-mouth disease virus (a member of the picornavirus group) rna could be translated effectively in an s-30 extract from ehrlich ascites tumour cells. this translation was inhibited by aurintricarboxylic acid, cycloheximide, puromycin and rnase. cell-free products of translation were identified by disc gel electrophoresis and immunoprecipitation with specific antisera. gel electrophoresis of the products without prior immunoprecipitation suggested the synthesis of some of the non-capsid pro ...	1976	61250
further studies of the physical and metabolic properties of foot-and-mouth disease virus temperature-sensitive mutants.	three temperature-sensitive (ts) mutants of foot-and-mouth disease virus were classified as ribonucleic acid negative and as belonging to the same complementation group when measured by virus yields and 3h uridine incorporation in paired, mixed infections at the nonpermissive temperature (38.5c). mutant ts-22, the only mutant able to produce plaques at 38.5 c, was more sensitive to acid than were the parental wild-type or other mutant viruses. diethylaminoethyl-dextran did not enhance the plaque ...	1976	5377
cultivation of foot and mouth disease virus in bovine leukocyte cultures for use in the complement fixation test.	bovine leukocyte cultures achieved good growth after 72 hours of cultivation. foot-and mouth disease (fmd) virus type 0 multiplied in such cultures to a titre of 10(6) tcid50/0.1 ml. the cell culture-grown virus was found to be suitable for the complement fixation test (cft) after purification and concentration with calcium phosphate.	1976	9808
physico-chemical properties of swine vesicular disease virus.	titration of svdv on primary pig kidney cell cultures revealed a plating efficiency of less than or equal to 0,9 x 10(-3). concentration and purification of the svd-virus propagated on pig kidney cell cultures were done by chloroform treatment, adsorption, differential- and density gradient centrifugation. the following physical parameters were found: svdv is an isometrical rna-virus having a diameter of 25,1 +/- 1,0 nm. it is resistent to the action of chloroform, ether and ph. the virus has a ...	1976	10872
effect of methyl glyoxal on infectivity and antigenicity of foot-and-mouth disease virus.	the inactivating effect of methyl glyoxal on foot-and-mouth disease (fmd) virus was studied. the rate of inactivation depended upon the drug concentration, incubation temperature and ph of the medium. rna recovered from the inactivated virus was not infectious. the complement-fixing activity of the virus was not reduced by methyl glyoxal treatment. the antigenicity of inactivated virus preparations determined by levels of virus neutralizing antibody in the blood sera of immunized white rats and ...	1976	11665
[several criteria of evaluation of foot-and-mouth disease virus reproduced in cell cultures in suspension].	the study of the plaques produced by viruses asia and o1 reveals different properties which may depend on the virus or on the cell or its method of culture. antigenic differences and subsequent immunological differences correspond to differences in plaques. on the other hand, the cell line in suspension evolves both in its morphology and its receptivity during the passages. all these variations imply the observations of quantitative and qualitative criteria of evaluation in order to prepare vacc ...	1976	71255
[antigenic structures of the foot-and-mouth disease virus].		1976	67699
[resistance of vaccinated animals to heterologous subtypes of the foot-and-mouth disease virus].		1976	176768
foot-and-mouth disease virus rna. presence of 3'-terminal polyriboadenylic acid and absence of amino acid binding ability.		1976	176778
a comparison of molecular weights of foot-and-mouth disease virus rna fragments determined from lengths and s-rates.	a comparison was made of the calculated mol. wt. of rna fragments from foot-and-mouth disease virus (fmdv) types a12 strain 119, c3 resende and o1 brugge. the mol. wt. were calculated by two methods: from the measurements of strand lengths in the electron micrographs and from the observed sedimentation rates (s-rates). rna extracted from virus by dialysis against water usually had three to four prominent strands of different lengths. mol. wt. calculated from s-rates (and converted to strand leng ...	1976	177721
characterization of the minor polypeptides in the foot-and-mouth disease particle.	in addition to the four major polypeptides vp1 and vp4, foot-and-mouth disease virus particles contain two minor polypeptides, mol. wt. 40 x 10(3) (p40) and 52 x 10(3) (p52). extensive purification procedures failed to remove these minor polypeptides from the virus particles. polypeptide p40 co-electrophoresed in sds-polyacrylamide gels with vp0, the probable precursor of vp2 and vp4 and was inaccessible to iodination in situ. the second minor polypeptide, p52, co-electrophoresed with the virus ...	1976	177728
experimental placental transfer of foot-and-mouth disease virus in mice.	an attenuated type o foot-and-mouth disease (fmd) virus which was virulent for infant, but not for pregnant, mice proved to be superior to a virulent type c fmd virus in the development of a model system for the study of placental transfer of fmd in mice. when mice were inoculated at day 8 or 12 of gestation with type o fmd virus, the virus was detectable in the maternal pancreas for 3 days and in the placenta for 6 days. viral levels in the fetus and the amniotic fluid were inconsistent and wer ...	1976	179452
the production of foot-and-mouth disease virus from bhk 21 c 13 cells grown on the surface of glass spheres.	in view of the advantages which are associated with the use of the bhk monolayer cell for the production of foot-and-mouth disease (fmd) virus, a unit system using glass spheres was developed to grow bhk monolayer cells and to test the susceptibility of such cells to fmd virus. the yield of cells and their susceptibility compares favorably with green bhk monolayer cells which have been grown in roux bottles.	1976	179634
the production of foot-and-mouth disease virus from bhk 21 c 13 cells grown on the surface of deae sephadex a50 beads.	methods are described which make possible the production of foot-and-mouth disease (fmd) virus from bhk 21 c13 monolayer cells which have been grown on the surface of serum coated deae sephadex a50 beads. the yield of cells and their susceptibility to infection by fmd virus are equivalent to conventional roux monolayer systems. the potential for the commercial application of the deae sephadex a50 system is discussed in relation to other unit process monolayer systems and in particular to the sys ...	1976	179635
growth of foot-and-mouth disease virus in the upper respiratory tract of non-immunized, vaccinated, and recovered cattle after intranasal inoculation.	non-immunized, vaccinated, and recovered cattle were inoculated intranasally with various doses of foot-and-mouth disease virus. samples of oesophageal-pharyngeal (op) fluid were taken periodically for up to 7 days after inoculation and virus titres of these samples were plotted as pharyngeal virus growth curves. in non-immunized cattle, the length of the lag period and of the growth period were inversely proportional to the dose of virus given. maximum titres were observed when clinical signs w ...	1976	180177
use of cell cultures with persistent virus infections to test the efficacy of antiviral compounds.	bhk-21 cells persistently infected with either vaccinia or foot and mouth disease virus were used to study the efficacy of antiviral compounds. the results of the persistent infection cell culture (picc) test were compared with those obtained by the plaque reduction (pr) test. the comparison showed that: (1) the picc test is more informative than the pr test; (2) stimulative as well as inhibitory activities of compounds are detectable, and (3) since the picc test can be carried on for several we ...	1976	182439
susceptibility of the indian squirrel to foot-and-mouth disease virus.		1976	183340
[some modern data on the antigenic makeup of the foot-and-mouth disease virus and their practical significance].		1976	183347
[electrophoretic studies of foot-and-mouth disease virus subtypes a1-a5 from various sources using carrier-free zone electrophoresis in a glucose density gradient].		1976	183418
[local interferon production in cattle after intranasal infection with avirulent ibr/ipv virus and its effect on a subsequent infection with foot-and-mouth disease virus].		1976	183421
[structure of foot-and-mouth disease virus].		1976	183422
survival of foot-and-mouth disease virus in cheese.	persistence of foot-and-mouth disease virus during the manufacture of cheddar, mozzarella, camembert cheese prepared from milk of cows experimentally infected with the virus was studied. cheese samples were made on a laboratory scale with commercial lactic acid starter cultures and the microbial protease marzyme as a coagulant. milk was heated at different temperatures for different intervals before it was made into cheese. food-and-mouth disease virus survived the acidic conditions of cheddar a ...	1976	184130
localisation on foot-and-mouth disease virus (fmdv) of an antigenic deficiency induced by passage in bhk cells.	passage of fmdv in bhk suspended cells was confirmed to induce an antigenic deficiency on the virion. by immunodiffusion experiments with complete virus, with trypsin-treated virus and with 12s virus fraction it was shown that the induced antigenic deficiency is located on the trypsin-removable part of the virion. these results were confirmed by absorption experiments.	1976	184763
effect of heat on foot-and-mouth disease virus (fmdv) in the components of milk from fmdv-infected cows.	foot-and-mouth disease virus (fmdv) survived in skim milk, cream and the pelleted cellular debris components of milk obtained from fmdv-infected cows after pasteurization at 72 degrees c for 0-25 min. virus was recovered from whole milk of infected cows after that milk was heated at 72 degrees c. for 5 min. and from the skim milk component after it was heated at the same temperature for 2 min. evaporation of the whole milk samples after they were heated at 72 degrees c. for 3 min. did not inacti ...	1976	185284
pathogenesis of foot-and-mouth disease: clearance of the virus from the circulation of cattle and goats during experimental viraemia.	viraemia is an important aspect of the pathogenesis of infectious diseases, but the mechanisms of entry and removal of virus from the vascular system particularly in natural hosts are poorly understood. the results of this study showed that the clearance of foot and mouth disease virus (fmdv) from the circulation of cattle and goats followed the general rules for the clearance of inert particulate materials and other viruses from the circulation. high doses of infused fmdv were cleared less effi ...	1976	185289
[occurrence of an increased reaction to challenge infection after vaccination with aerosols of inactivated foot-and-mouth disease virus].		1976	961209
further observations of foot and mouth disease virus type s.a.t 1 infection of cattle in tanzania.		1976	16300346
a comparative chemical and serological study of the full and empty particles of foot-and mouth disease virus.	the chemical and serological properties of the full, naturally occurring empty and artificially produced empty particles of foot-and-mouth disease virus, serotype a(subtype 10, strain 16) have been studies. the full 146s particles comprised the virus rna, three polypeptides (vp1 to vp3) mol. wt. about 30 x 10-3, one polypeptide (vp4) mol. wt. about 13-5 x 10-3, and a small amount of a polypeptide (vpo) mol. wt. about 43 x 10-3. the naturally occurring 75s empty particles contained no rna and muc ...	1975	235596
temperature-sensitive mutants of foot-and-mouth disease virus: the isolation of mutants and observations on their properties and genetic recombination.	a number of temperature-sensitive mutants were isolated from two strains of foot-and-mouth disease virus (fmdv). various properties of the mutants were examined including comparative growth curves at permissive and restrictive temperatures, cut-off temperatures, thermal lability and ph sensitivity. recombination was observed between various pairs of mutants of fmdv strain pacheco. it occurred early in the growth cycle and the proportion of recombinants remained constant thereafter. maximum recom ...	1975	237977
[foot and mouth disease virus].		1975	185664
evidence for recombination between two different immunological types of foot-and-mouth disease virus.	recombination was observed between temperature-sensitive (ts) mutants of two immunological types of foot-and-mouth disease virus which were distinguishable by two marker characteristics in addition to their antigenic type. putative ts+ recombinants were isolated and the segregation patterns of their marker characteristics examined. the results are discussed in terms of the origin of new sub-type strains.	1975	180948
[comparative serological study of the principal strains of the foot and mouth disease virus isolated in ethiopia 1969-1974].		1975	181797
a major difference in the strategy of the calici- and picornaviruses and its significance in classification.	pig kidney (1brs-2) cells infected with vesicular exanthema virus (vev), a calicivirus, did not contain any large precursor polypeptides similar to those found when they were infected with foot-and-mouth disease virus (fmdv). the largest induced protein found in the vev-infected cells had a molecular weight identical with that of the virus structural polypeptide. this difference in strategy between vev and fmdv, taken in conjunction with the morphological and structural differences described pre ...	1975	178628
[study of the indirect complement fixation test for use in the differentiation of foot-and-mouth disease viruses and the determination of immunity].	studies were carried out to establish the optimal conditions for the indirect complement-fixation test (icft) and explore the possibility to use the test in differentiating the foot-and-mouth disease (fmd) viruses and checking the immunity obtained in survivals or in animals that had been vaccinated against fmd. it was demonstrated that the proper use of icft necessitates in turn the use of a minimal amount of antigen, which in the presence of 1-2 e homologous hyperimmune serum completely binds ...	1975	179191
the use of the haemagglutination-inhibition test for detecting antibodies to type sat 2 foot-and-mouth disease viruses in cattle sera.	two strains of type sat 2-foot-and-mouth disease virus which gave high titres of haemagglutinin activity reacted type-specifically in direct haemagglutination-inhibition tests with reference, bovine convalescent antisera. comparisons of the haemagglutination-inhibition and the serum neutralization tests using cattle sera showed that both were equally specific and sensitive for detecting virus antibody.	1975	163274
[cultivation of the foot-and-mouth disease virus in continuosly inoculated cells of piglet kidney].		1975	163519
[setting up a neutralization reaction for the foot-and-mouth disease virus].		1975	163521
[complement fixation micromethod for determining the type of foot-and-mouth disease virus].		1975	163522
some investigations on the adjuvant mechanism of deae dextran.	in vitro it was shown that adsorption of inactivated fmdv onto deae-d kieselgur columns did not occur in the presence of 0.1--0.15m nacl. these nacl concentrations are present in deae-d/fmdv vaccines and in the tissues of animals. therefore, adsorption of virus antigen does not appear to be responsible for the adjuvant effect of deae-d. in pigs it was demonstrated that deae-d exerts its optimal adjuvant effect, as measured by the formation of neutralizing antibodies and protection against challe ...	1975	164161
a comparison of some immunological methods for the differentiation of strains of foot-and-mouth disease virus.	two fmdv strains which had been previously differentiated by complement-fixation were compared by guinea-pig protection test, kinetic neutralization and micro-neutralization tests. it was found that these tests, which have not been previously applied by the methods described, were all capable of fmdv strain differentiation. similar differences were found by all methods, which suggests that comparisons made by cross-cf, cross-neutralization or cross-protection involve measurement of the same anti ...	1975	164500
the sub-type classification of strains of foot-and-mouth disease virus.	sixteen foot-and-mouth disease virus (fmdv) strains of type sat 1 were compared in complement-fixation tests. with the test used, the range of antigenic variation within a type appeared to be greater than previously described. the concept of a sub-type group within which all strains are more closely related to each other than to any strain outside the group was not supported. considering the group of strains studied, it is suggested that the classification of strains is best achieved by moninati ...	1975	164501
proteins induced in bhk cells by infection with foot-and-mouth desease virus.	although the infection of bhk cells with foot-and-mouth disease virus did not cause a marked inhibition of cellular protein synthesis, the proteins synthesized gradually changed from host-specific to virus-specific. the synthesis of at least thirteen virus-induced proteins was demonstrated by polyacrylamide electrophoretic analysis of the infected cells. only a small proportion of the virus-induced proteins was incorporated into the mature virus particles. the addition of amino acid analogues ca ...	1975	164515
removal of acetylethyleneimine from suspensions of inactivated foot-and-mouth disease virus.		1975	166252
[influence of varying storage temperatures on the infectivity and antigenicity of foot-and-mouth disease virus strains before and after inactivation].		1975	166530
the effect of acetylethyleneimine upon a strain of inactivated foot-and-mouth disease virus stored at 4 degrees c.	the presence of either thiosulphate-neutralized or free aei was shown to degrade inactivated foot-and-mouth disease virus type o (hong kong) antigen during storage at 4 degrees c. deterioration was evident after 20 weeks of storage and little antigen remained at 36 weeks. optimum stability was obtained by removing the residual inactivant immediately after inactivation.	1975	166627
effect of pasteurization and evaporation on foot-and-mouth disease virus in whole milk from infected cows.	the effects of pasteurization and evaporation on foot-and-mouth disease virus in whole milk from infected cows obtained one day postinoculation were studied. virus survived the heating of milk at high temperature-short time pasteurization at 75 degrees c for 15-17 seconds. in addition, virus from infected milk survived heating at 80 degrees c for the same time. infective virus also survived in the pasteurized milk after evaporation at 65 degrees c to 50% of the original volume. the bovine udder ...	1975	166740
production, isolation, and partial characterization of three foot-and-mouth disease virus temperature-sensitive mutants.	three high temperature-sensitive (ts) mutants of foot-and-mouth disease virus were characterized by their relative abilities to grow at 33 or 38.5 c, to kill infant mice, to infect guinea pigs, and to produce foot-and-mouth disease in steers. mutants ts-24 and ts-42 did not grow at 38.5 c; both may have produced considerable quantities of noninfectious virus particles at 33 c. a third mutant, ts-22, appeared "leaky" because it multiplied to a limited extent during prolonged incubation at the non ...	1975	166915
studies with foot-and-mouth disease virus in british deer (muntjac and sika). clinical disease, recovery of virus and serological response.		1975	167058
a genetic recombination map of foot-and-mouth disease virus.	sixty ts mutants were isolated from the pacheco strain of type o foot-and-mouth disease virus after treatment with either 5-fluorouracil or hydroxylamine. the conditions affecting recombination and assay of the ts+ recombinants were standardized. using two ts mutants resistant to guanidine, three-factor crosses, supported by two-factor crosses, located 34 of the mutations in a linear arrangement. the recombination frequencies between certain pairs of mutations were additive. the guanidine charac ...	1975	167118
the pathogenicity of bovine strains of foot and mouth disease virus for impala and wildebeest.	impala (aepyceros melampus) and wildebeest (connochaetes taurinus) were infected with bovine strains of foot and mouth disease virus by intradermolingual inoculation. no clinical signs developed in the impala but mild atypical lesions developed in the tongues of the wildebeest with generalized spread to one foot in two of the eight animals exposed. all the impala but only some of the wildebeest developed viraemia. no virus could be isolated from any tissues in either species after the 7th day fo ...	1975	167208
cross-reactions of normal bovine serums to foot-and-mouth disease virus in plaque-reduction neutralization and radial immunodiffusion.	serums from 150 cattle with no known exposure to foot-and-mouth disease (fmd) virus were tested by both the plaque-reduction neutralization (prn) technique and the radial immunodiffusion (rid) technique to evaluate the significance and the extent of cross-reactions in these tests. serums from 30 cattle from each of 5 locations were tested against representative viruses of each of the 7 types of fmd virus. high levels of cross-reactions with both the rid and prn techniques were found in serums of ...	1975	167625
binary ethylenimine as an inactivant for foot-and-mouth disease virus and its application for vaccine production.	foot-and-mouth disease virus was inactivated with binary ethylenimine formed apart from or directly in the virus suspension by the cyclization of 2-bromoethylamine hydrobromide or 2-chloroethylamine hydrochloride under alkaline conditions. the inactivation rates with binary ethylenimine prepared apart from the virus suspension in dilute sodium hydroxide with either 2-bromoethylamine hydrobromide or 2-chlorethylamine hydrochloride were higher than with pure ethylenimine. when binary ethylenime wa ...	1975	167679
virulence of temperature-sensitive mutants of foot-and-mouth disease virus.	a number of temperature-sensitive mutants isolated from two strains of foot-and-mouth disease virus were examined for their virulence in suckling mice. the majority of the mutants were found to be less virulent than the parent virus strains, ranging from slight to total attenuation, but two mutants retained parental levels of virulence. there was no correlation between mutant cut-off temperatures and virulence, or the revertant content of mutant preparations and virulence. it was not always poss ...	1975	167681
the survival of foot-and-mouth disease virus in open air conditions.	the influence of the open air factor (oaf) and daylight on the survival of foot-and-mouth disease (fmd) virus held as captured aerosols on spider microthreads has been investigated. virus inactivation due to oaf was slight. similarly, the effect of daylight on the survival of virus was not marked. the results are discussed in relation to the airborne spread of fmd virus in nature.	1975	168250
[studies on the influence of the host system on the result of the neutralization of monodispersed and untreated foot- and mouth disease virus (author's transl)].	monodispersed foot- and mouth disease virus was obtained by filtration through membranes having a porosity only twice the diameter of the virus. this monodispersed virus was neutralized by immune sera in the same manner as not treated virus. this was shown by the inactivation curve comparing the amount of virus used for the test (calculated as id50) with the neutralization titre (nd50) or comparing the reduction of infectivity (also calculated as id50) with the dilution factor of the antiserum. ...	1975	169651
influence of serum restriction on foot-and-mouth disease virus infections in cell cultures. i. enhanced viral susceptibility.		1975	169654
influence of serum restriction on foot-and-mouth disease virus infections in cell cultures. ii. altered viral replication.		1975	169655
[discovery of the foot-and-mouth disease virus].		1975	171130
immune and antibody responses to an isolated capsid protein of foot-and-mouth disease virus.	the purified capsid proteins vp1, vp2, and vp3 of foot-and-mouth disease virus type a12 strain 119 emulsified with incomplete freund's adjuvant were studied in swine and guinea pigs. swine inoculated on days 0, 28, and 60 with 100-mug doses of vp3 were protected by day 82 against exposure to infected swine. serums from animals inoculated with vp3 contained viral precipitating and neutralizing antibodies, but such serums recognized fewer viral antigenic determinants than did antiviral serums. cap ...	1975	171309
n-terminal amino acid sequences in the major capsid proteins of foot-and-mouth disease virus types a, o, and c.	sequences of amino acids at the n-termini of virus proteins vp1, vp2, and vp3 were determined for foot-and-mouth disease virus types a12 strain 119, o1brugge and c3resende. in the polyacrylamide gel electrophoresis system used to purify the proteins, vp3 migrated faster than vp1 or vp2; and in the virion, vp3 could be cleaved by trypsin into vp3a and vp3b. the n-terminal amino acids for each of the virus types were glycine in vp1, aspartic acid in vp2, and threonine in vp3. no divergences in seq ...	1975	171452
[electron microscopy studies on proliferation of foot-and-mouth disease virus in cell cultures. i. morphologic changes in cell nucleus].	the first morphological indication of fmd infection of a cell culture was in the nucleus. components of nucleoli became segregated and were finally present only as remnants. it was not possible to distinguish different stages of segregation, as in the case of entero-virus infections, because of the rapidity of fmd virus proliferation. following changes in nucleoli there was margination of chromatin. particularly striking was an increase in interchromatin granules. changes in the nuclear membrane ...	1975	172041
[electron microscopy studies on the proliferation of foot-and-mouth disease virus in cell cultures. ii. changes in nucleic acid metabolism of the cell nucleus].	bhk cells were infected with fmd virus and treated with tritium-labelled thymidine and uridine for examination by autoradiography under the electron microscope. labelling of the dna, examined by autoradiography under the optical microscope, showed inhibition of 3h-thymidine incorporation. for demonstrating rna labelling of nuclei, some cells were treated with actinomycin d and others were left untreated. under the lectron microscope there was no evidence of increased 3h-uridine incorporation in ...	1975	172042
[electron microscopy studies on the proliferation of foot-and-mouth disease virus in cell cultures. iii. morphogenesis in cytoplasm].	the previous parts have been concerned with the participation of the cell nucleus in the formation of the rna of fmd virus. however, the actual morphogenesis of the virus takes place in cytoplasm. in bhk cells, changes attributable to virus infection were visible by the second hour, with the formation of threads and large polysome complexes near the nucleus. viral particles soon appeared between these structures. there were no pronounced foci of viroplasma, and it seemed that they were not neces ...	1975	172043