mitochondrial and herpesvirus-specific deoxypyrimidine characterize and compare the thymidine (tdr) and deoxycytidine (cdr) kinase isozymes of uninfected and herpesvirus-infected cells: (i) the subcellular distribution of the isozymes has been studied; (ii) a specific assay for cdr kinase has been devised; (iii) the tdr kinase isozymes have been partially purified; and (iv) the purified enzymes have been analyzed by disc polyacrylamide gel electrophoresis, isoelectric focusing, and glycerol gradient centrifugation and by substrate competition and ...1975169387
fluorosugars inhibit biological properties of different enveloped viruses.both 2-deoxy-2-fluoro-d-glucose and 2-deoxy-2-fluoro-d-mannose were found to be potent inhibitors of the synthesis of infectious semliki forest and fowl plague virus in chicken embryo cells and also of pseudorabies virus grown in rabbit kidney cells. it was found that the pseudorabies virus-mediated cell fusion and the synthesis of functional hemagglutinin of fowl plague virus were blocked. in all cases the 2-deoxy-2-fluoro-d-mannose-caused inhibition was stronger than the 2-deoxy-2-fluoro-d-glu ...1976178923
cleavage of concatemeric dna at the internal junction of "translocation" mutants of pseudorabies virus and inversion of their l component appear to be linked.when pseudorabies virus (prv) strains are grown in chicken embryo fibroblasts (cef), variants ("translocation" mutants) arise in which there is a duplication of the leftmost sequences of the genome and their translocation in inverted orientation next to the internal inverted repeat bracketing the s component. in these variants, the ul becomes bracketed by inverted repeats and is found in two orientations relative to the us. to study the cis-functions involved in cleavage of concatemeric dna as w ...19921310557
glycoprotein gi of pseudorabies virus promotes cell fusion and virus spread via direct cell-to-cell transmission.mutants of pseudorabies virus defective in either glycoprotein gi or giii are only slightly less virulent for mice and chickens than is wild-type virus, while mutants defective in both gi and giii are avirulent. to clarify the reason for the lack of virulence of the gi- giii- mutants, we have analyzed in some detail the interactions of these mutants with their hosts. the results obtained showed that the gi glycoprotein is an accessory protein that promotes cell fusion. this conclusion is based o ...19921312633
expression of the marek's disease virus (mdv) homolog of glycoprotein b of herpes simplex virus by a recombinant baculovirus and its identification as the b antigen (gp100, gp60, gp49) of mdv.a gene encoding a homolog of glycoprotein b of herpes simplex virus (gb homolog) has been identified on the marek's disease virus (mdv) genome (l. j. n. ross, m. sanderson, s. d. scott, m. m. binns, t. doel, and b. milne, j. gen. virol. 70:1789-1804, 1989); however, the molecular and immunological characteristics of the gene product(s) are still not clear. in the present study, the gb homolog of mdv was expressed in insect cells by a recombinant baculovirus, and it was characterized to determine ...19921313890
effects of pseudorabies virus infection upon cytotoxicity and antiviral activities of porcine alveolar macrophages.alveolar macrophages (am) infected with pseudorabies virus (prv) were compared to noninfected am for cytotoxicity against foreign or transformed cells and production of interferon (ifn). five prv strains were used to infect am including strains that are known to be highly virulent for pigs, i.e. strain 4892 and strain s-62 as well as strains that are regarded as mild or nonvirulent, i.e. buk and bartha. the multiplicity of infection ranged from 0.005 to 0.05 tcid50/cell. the target cells in the ...19921330423
the ability of pseudorabies virus to grow in different hosts is affected by the duplication and translocation of sequences from the left end of the genome to the ul-us junction.pseudorabies virus is a herpesvirus which has a class 2 genome. however, under certain growth conditions it acquires a genome with class 3-like characteristics. in these variants, the leftmost sequences of the long (l) component of the viral genome have been duplicated and translocated to the right of the l component next to the short (s) component, resulting in an l component that is bracketed by inverted repeats. consequently, the l component can invert and is found in two orientations relativ ...19911656073
avirulent ts and thymidine kinase-deficient mutant of aujeszky's disease virus.the temperature-sensitive (ts), thymidine kinase-deficient (tk-) mutant designated zhtstk- strain, of aujeszky's disease virus (adv) was isolated from a virulent strain with the treatments using 5-bromodeoxyuridine and arabinosylthymine. the zhtstk- strain was easily distinguished from the other virulent adv strains by plaque size on hmlu-1 and chicken embryo fibroblast cells and by restriction endonuclease analyses using bam hi, sal i and kpn i. the zhtstk- strain was avirulent for mice, guinea ...19911657212
acquisition of an additional internal cleavage site differentially affects the ability of pseudorabies virus to multiply in different host cells.the translocation of the 325 leftmost bp of the genome of pseudorabies virus (prv) to the internal junction between the l and s components confers upon the virus a growth advantage relative to wild-type prv in chicken embryo fibroblasts (cefs) and chickens and a growth disadvantage in rabbit kidney (rk) cells and mice. to clarify the molecular basis for the species-specific growth characteristics of the translocation mutants, we have compared several parameters of the virus growth cycle in cefs ...19911658364
[the synergistic antiviral effect of acyclovir and ribavirin against the herpes simplex type-1 virus and the pseudorabies virus in vitro].the antiviral effect of the combination acyclovir (acv) and ribavirin (r) on herpes simplex virus type 1 (hsv-1) in diploid cell culture of human embryonal skin and muscle fibroblasts and the virus of pseudorabies in secondary culture of chicken embryonal fibroblasts is studied. the antiviral activity is studied under the checker-board combinations of twofold dilutions of the two substances on the basis of inhibition of the virus cytopathic effect in microplates. the viruses are applied at 100 c ...19902166426
complex between glycoproteins gi and gp63 of pseudorabies virus: its effect on virus ascertain the biological functions of different glycoproteins that are nonessential for pseudorabies virus growth in vitro, we have constructed mutants defective in one (or a combination) of these glycoproteins and have examined various aspects of their role in the infective process. we made the following two observations. (i) glycoproteins gi and gp63 are noncovalently complexed to each other. they are coprecipitated by antisera against either one of these glycoproteins but do not share anti ...19882460638
hemagglutination with pseudorabies virus. brief report.pseudorabies virus grown in cpk cell cultures was tested for hemagglutination (ha) with erythrocytes of a variety of species at 4 degrees c, 25 degrees c and 37 degrees c. ha was observed at all temperatures with mouse erythrocytes but not with cattle, sheep, goat, swine, cat, rabbit, guinea pig, rat, mongolian gerbil, chicken, and goose erythrocytes. mice showed a strain variation in agglutinability of their erythrocytes, requiring selection of mice to obtain erythrocytes for ha. the ha reactio ...19892549922
release of pseudorabies virus from infected cells is controlled by several viral functions and is modulated by cellular components.the role of the nonessential glycoproteins gi, gp63, and giii in the release of pseudorabies virus from different cell lines was investigated. we show that these glycoproteins may have a beneficial or deleterious effect on virus release depending on the type of cell in which the virus is grown. inactivation of the genes encoding either gi, gp63, or giii has no detectable effect on virus release from rabbit kidney cells. inactivation of gi or gp63 strongly promotes virus release from chicken embr ...19892555567
multiple defects in the genome of pseudorabies virus can affect virulence without detectably affecting replication in cell culture.several independently isolated vaccine strains of pseudorabies virus were studied to identify the functions that play a role in the expression of virulence of this virus. all the strains that were studied grew well in three different cell types. no differences that could be correlated with avirulence could be detected either in the virus yield produced by the cells or in the length of the eclipse phases. all the attenuated strains, however, had lost their ability to replicate efficiently in the ...19872823461
role of a structural glycoprotein of pseudorabies in virus virulence.the virulence of deletion mutants of pseudorabies virus defective in the expression of glycoprotein gi, gp63, or both was tested in 1-day-old chickens and young pigs. in the absence of expression of gi, the virulence of a fully virulent laboratory strain, prv(ka), for 1-day-old chickens was reduced approximately fourfold. inactivation of glycoprotein gp63 appeared also to affect the virulence of prv(ka) only slightly, as did inactivation of both gi and gp63. the level of reduction in virulence, ...19872824832
host cell-specific growth advantage of pseudorabies virus with a deletion in the genome sequences encoding a structural glycoprotein.several attenuated strains of pseudorabies virus contain genomes that carry a deletion in their short unique (us) component. the sizes of the deletions are different in the various attenuated strains; the deletions may include part of one of the inverted repeats as well as part of the us region of the genome. in most cases, the deletion includes the gene encoding the glycoprotein gi. the attenuated strains with a deletion in their s component have a common history of having been cultivated in ch ...19882824839
relative rates of aujeszky's disease virus attenuation, as assessed in mice.field strains of aujeszky's disease virus (adv) were attenuated by heat treatment and serial passage at sub-optimal growth temperatures in chicken embryo fibroblasts (cef). at chosen passage levels, virus was titrated in cell culture and in mice. for each strain, the pathogenicity was expressed as a mouse lethal index (mli), defined as the inverse of the log10 (ccid50:ld50). mlis determined for field strains displayed a wide range of comparatively high values. the attenuation of field strains wa ...19872829412
role of glycoprotein giii of pseudorabies virus in virulence.deletion mutants of pseudorabies virus unable to express glycoprotein giii, gi, or gp63 or double and triple mutants defective in these glycoproteins were constructed, and their virulence for day-old chickens inoculated intracerebrally was determined. mutants of wild-type pseudorabies virus defective in glycoprotein giii, gi, or gp63 were only slightly less virulent (at most, fivefold) for chickens than was the wild-type virus. however, mutants defective in both giii and gi or giii and gp63 were ...19882839697
proteins specified by the short unique region of the genome of pseudorabies virus play a role in the release of virions from certain cells.two pseudorabies virus vaccine strains (bartha and norden) that have a similar deletion in the short unique (us) region of the genome have been identified previously (b. lomniczi, m. l. blankenship, and t. ben-porat, j. virol. 49:970-979, 1984). these strains do not code for the glycoprotein gi, a glycoprotein that has been mapped on the wild type virus genome by t. c. mettenleiter, n. lukacs, and h. j. rziha (j. virol. 53:52-57, 1985) to the sequences deleted from the vaccine strain. restoratio ...19863001344
herpesviruses provide helper functions for avian adeno-associated parvovirus.the avian herpesviruses infectious laryngotracheitis virus (iltv) and herpesvirus of turkeys (hvt), as well as the mammalian herpesvirus pseudorabies virus (prv) were able to provide complete helper activity for the production of infectious avian adeno-associated virus (aaav) in chicken cells. the presence of aaav in the infected chicken cell reduced the multiplication of hvt. iltv or prv, however, were not affected if used as helper viruses. infectious aaav was determined by an indirect immunof ...19863003233
genome location and identification of functions defective in the bartha vaccine strain of pseudorabies virus.we have shown previously (lomniczi et al., j. virol. 52:198-205, 1984) that the bartha vaccine strain of pseudorabies virus has a deletion in the short unique (us) region of its genome--a deletion that is related to the absence of virus virulence. this strain is, however, also defective in other genes involved in virulence. we show here that virulence can be restored by marker rescue of the bartha strain to which an intact us has been restored (but not to the parental bartha strain) by sequences ...19873027406
evolution of pseudorabies virions containing genomes with an invertible long component after repeated passage in chicken embryo fibroblasts.the genome of pseudorabies virus consists of two components, short (s) and long (l). only the s component is bracketed by inverted repeats, and only the s component inverts itself relative to the l component, giving rise to two isomeric forms of the genome. an attenuated vaccine strain of pseudorabies virus (norden), however, has a genome which is found in four isomeric forms (b. lomniczi, m. l. blankenship, and t. ben-porat, j. virol. 49:970-979, 1984). to determine the basis for the atypical s ...19873033309
[on the biological action of transition metal complexes. 1. the antiviral activity of palladium aminopyridin-complexes (author's transl)].some aminopyridine complexes of palladium and pdcl2 showed an antiviral in vitro activity against enveloped dna and rna viruses such as vaccinia virus, pseudorabies virus, ndv and fpv. in contrast, naked rna virus as mengovirus was not affected. the compounds were compatible for chicken embryo as well as fl cells in concentrations of 100-250 microm. the therapeutical index calculated from the maximally tolerated dose and the concentration causing a 50 per cent plaque reduction was determined wit ...19816267845
[electron microscopic study of the in vitro effect of dipyridamol on the pseudorabies virus].dipyridamole at a concentration of 50 microm/ml displays no activity on adsorption and penetration of pseudorabies virus in chicken embryonal cells. furthermore, first stages of virus replication take place within the nucleus, whereas incomplete virus cores defective in dna content are found within the nucleoplasm at times when the regular viral replication has been finished in controls. defective pseudorabies virus particles lacking in dna-content of the core, can be observed at the end of norm ...19826299017
susceptibility of marek's disease lymphoblastoid cell lines to infection with influenza and pseudorabies viruses and the protective effect of immunization with influenza virus-infected lymphoblastoid cells.the susceptibility of 3 lymphoblastoid cell lines (mdcc-msb1, mdcc-hp1 and mdcc-rp1) derived from marek's disease tumours to infection with influenza (aopr8) and pseudorabies viruses was studied. msb1 and hp1 were more susceptible to infection with influenza virus than was rp1. it was shown in the case of hp1, which was studied in greater detail, that although the majority of the cells synthesized influenza virus haemagglutinin when infected at high multiplicity, only a small proportion produced ...19826299231
a case of aujeszky's disease virus infection in young chicks.on a rearing farm with 96,000 birds, 10,000 three and four days old chicks died with nervous symptoms. a virus was isolated from the brains and identified as an aujeszky's disease virus. the isolate was very pathogenic for chickens up to about 7 days of age, causing mortality after parenteral injection (intracerebral, intraperitoneal, intramuscular) but not after oral, eye drop or spray application. an aujeszky vaccine virus, made apathogenic by passages in chicken cells for use in swine, had th ...19826301138
a study of two mutant strains of pseudorabies virus (prv) unable to express thymidine kinase (tk) function.two mutant strains of pseudorabies virus (prv) were selected from the virulent 86/27v virus treated with chemical drugs. the viruses, named 6a1 and 6c2, respectively, appeared to be unable to express thymidine kinase function, as demonstrated by the autoradiography test. they showed a reduced virulence for some susceptible animal species (chickens, mice, rabbits, calves, lambs and piglets) and virus was isolated sporadically. the mutant viruses appeared to be able to protect animals against infe ...19957483895
mutations affecting the ul21 gene contribute to avirulence of pseudorabies virus vaccine strain bartha.analysis of the live attenuated pseudorabies virus (prv) vaccine strain bartha indicated location of a major determinant for prv neurovirulence within the genomic bamhi fragment 4 (b. lomniczi et al., 1984, j. virol. 52, 198-205). to more precisely localize the defect, marker rescue experiments were performed using cloned subfragments of bamhi-4. rescuants were analyzed after intracerebral infection for their virulence in chicken, as well as after intranasal infection for virulence in pigs. we s ...19957571416
generation of thymidine kinase-deficient mutants of infectious laryngotracheitis virus.current vaccines for the avian respiratory disease infectious laryngotrachetitis consist of naturally attenuated strains of the causative agent--the herpesvirus infectious laryngotracheitis virus (iltv). due to the dissemination of these viruses from vaccinated chickens as well as their possible reversion to more pathogenic forms, the use of genetically engineered viral vaccines lacking virulence factors while retaining antigenicity is being considered. since the thymidine kinase (tk) activity o ...19957778265
molecular evolution of herpesviruses: genomic and protein sequence comparisons.phylogenetic reconstruction of herpesvirus evolution is generally founded on amino acid sequence comparisons of specific proteins. these are relevant to the evolution of the specific gene (or set of genes), but the resulting phylogeny may vary depending on the particular sequence chosen for analysis (or comparison). in the first part of this report, we compare 13 herpesvirus genomes by using a new multidimensional methodology based on distance measures and partial orderings of dinucleotide relat ...19948107249
identification of an infectious laryngotracheitis virus gene encoding an immunogenic protein with a predicted m(r) of 32 kilodaltons.the nucleotide sequence of an infectious laryngotracheitis virus (iltv) gene which maps immediately upstream from the glycoprotein 60 (gp60) gene was determined. the gene, designated p32, encodes a predicted polypeptide of 298 amino acids with an estimated m(r) of 32,000 daltons. the predicted protein sequence has four potential n-glycosylation sites and a signal sequence at the n-terminal region. amino acid residues in the nh2-terminal region of the p32 protein exhibit similarity to glycoprotei ...19938212855
deleting valine-125 and cysteine-126 in glycoprotein gi of pseudorabies virus strain nia-3 decreases plaque size and reduces virulence in mice.we investigated the function of antigenic domains on gi in virulence and immunogenicity. three prv gi mutants were constructed by deleting nucleotides coding for the following amino acids: valine-125 and cysteine-126, located in a discontinuous antigenic domain (m 303); glycine-59 and aspartic acid-60 located in a continuous antigenic domain (m304); and arginine-67 and alanine-68, located in a discontinuous antigenic domain (m305). mismatch primers in the polymerase chain reaction were used to i ...19938394068
replication-defective adenovirus type 5 as an in vitro and in vivo gene transfer vector in chickens.the capacity of e1a gene-deleted and thus replication-defective adenovirus type 5 (ad5) to transduce foreign genes in chicken embryo fibroblasts (cef) as well as in chickens was investigated. the lacz and luciferase genes were successfully transduced in cef by replication-defective ad5, demonstrating that these cells possess receptor(s) for binding and penetration of ad5. a single intramuscular inoculation of ad-gd, a replication-defective ad5 harbouring the gd gene of pseudorabies virus, in adu ...19958847523
biological properties of three mexican isolates of aujeszky's disease virus.four strains of aujeszky's disease virus (adv) were included in this study; three mexican field isolates (215,145 and c-8) in conjunction with the shope reference strain of adv, which has known pathogenic characteristics. all four strains were included in each treatment, which consisted of heat treatment, trypsin treatment and passed ten times on chicken embryo fibroblasts. both virus titer and plaque size were determined on the first and tenth passage and on treated and untreated strains. on ea ...19979291629
a chicken embryo eye model for the analysis of alphaherpesvirus neuronal spread and virulence.we describe use of developing chicken embryos as a model to study neuronal spread and virulence of pseudorabies virus (prv). at embryonic day 12, beta-galactosidase-expressing prv strains were injected into the vitreous humor of one eye, and virus replication and spread from the eye to the brain were measured by beta-galactosidase activity and the recovery of infectious virus from tissues. the wild-type prv strain, becker, replicated in the eye and then spread to the brain, causing extensive pat ...19989573221
genomic variations among wildtype and mutant strains of pseudorabies virus.both wild-type virulent and mutant strains of pseudorabies virus (prv) were used in this study. mutants used were derived from the plaque purified strain prvmaip. a total of six drug resistant mutants, three bromodeoxyuridine (budr) resistant and three iododeoxyuridine (iudr) resistant, respectively, were isolated and passaged in chicken embryo fibroblast (cef) cells. the dna of these prvs were compared with the wild-type isolates by means of the restriction fragment pattern (rfp) findings produ ...200211942085
corticosteroids are unable to protect against pseudorabies virus-induced tissue damage in the developing brain.after intraocular injection of the virulent pseudorabies virus (prv) strain becker into late-stage chicken embryos, the virus spreads and replicates in the brain, where severe edema and hemorrhaging follow. by contrast, the attenuated bartha strain does not cause severe brain pathology despite viral replication and spread throughout the brain (b. w. banfield, g. s. yap, a. c. knapp, and l. w. enquist, j. virol. 72:4580-4588, 1998). these observations prompted us to explore the mechanism by which ...200312663804
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