the effect of loss of regulation of minus-strand rna synthesis on sindbis virus replication.during the replication cycle of sindbis virus minus-strand synthesis stops normally at the time that plus-strand synthesis reaches a maximum rate. we have isolated and characterized revertants of ts24, a member of the a complementation group of sindbis hr mutants, that we had demonstrated previously to have a temperature-sensitive defect in the regulation of minus-strand synthesis. these revertants of ts24 replicated efficiently at 40 degrees but nevertheless retained the temperature sensitive d ...19863705466
effect of interferon on vero cells persistently infected with sspe virus and lytically infected with measles virus.the effect of lymphoblastoid interferon (ifn) on viral polypeptides synthesized in a vero cell culture persistently infected with subacute sclerosing panencephalitis virus (sspe-vero) was compared to that of vero cells infected with exogenous measles virus. after ifn treatment there was no significant decrease in the synthesis of sspe viral proteins, but inhibition of synthesis of measles polypeptides was readily seen. in vero and sspe-vero cells ifn was able to inhibit replication of sindbis vi ...19863729726
identification of the inflammatory cells present in the central nervous system of normal and mast cell-deficient mice during sindbis virus encephalitis. 19863742614
effect of concanavalin a on early interactions of sindbis virus with goose erythrocytes and bhk 21 cells.the role of mannose containing molecules in sindbis virus envelope glycoproteins and cell membrane receptors was investigated by means of concanavalin a (con a). treatment of virus or bhk 21 cells with the lectin before infection reduced viral infectivity. hemagglutination and hemolysis showed a different sensitivity to con a. hemagglutination was not affected by the lectin and treatment of erythrocytes with con a produced an enhancement of agglutinability by the virus. hemolytic activity was, o ...19863747853
sequence analysis of the e2 gene of a hyperglycosylated, host restricted mutant of sindbis virus and estimation of mutation rate from frequency of revertants.svap15/21, a strain of sindbis virus (sv) derived from our standard laboratory strain of sv (svstd) after repeated passage on aedes albopictus cells, grows normally in mosquito cells but is host restricted (hr) in vertebrate cells. it is also temperature sensitive (ts) and produces pinpoint plaques on vertebrate cells (sp). e2 glycoprotein of svstd differs from that of the more widely used svhr (from which svstd was derived) by an additional (i.e., third) n-linked glycan. the e2 of svap15/21, in ...19863750843
deletion mapping of sindbis virus di rnas derived from cdnas defines the sequences essential for replication and packaging.defective-interfering (di) genomes of a virus contain sequence information essential for their replication and packaging. they need not contain any coding information and therefore are a valuable tool for identifying cis-acting, regulatory sequences in a viral genome. to identify these sequences in a di genome of sindbis virus, we cloned a cdna copy of a complete di genome directly downstream of the promoter for the sp6 bacteriophage dna dependent rna polymerase. the cdna was transcribed into rn ...19863753584
novel preparation of functional sindbis virosomes.lipid and protein factors important for the preparation and stability of reconstituted membranes prepared by the insertion of detergent-solubilized sindbis virus glycoproteins into preformed lipid vesicles have been defined. it was found that both the state of aggregation of the membrane protein and the phase of the lipid are critical for the insertion of proteins into preformed lipid vesicles. the membranes prepared with the insertion technique were characterized in terms of residual detergent, ...19863756136
circulation of mosquito-borne viruses in large-scale sheep farms in eastern slovakia.samples of blood sera collected from 608 sheep in large farms of the districts of trebisov, michalovce, vranov nad toplou and humenné were investigated in hemagglutination-inhibition test for the presence of mosquito-borne viruses sindbis, west nile, tahyna and calovo. antibodies to arboviruses tahyna (11.5%) and calovo (10.9%) were detected most frequently, while a lower sero-positivity was recorded to the sindbis (2.3%) and west-nile (1.0%) viruses. certain differences were found in the infect ...19863758873
dominance of the cpe(+) phenotype in hybrid aedes albopictus cells infected with sindbis virus.the effect of sindbis virus (sv) infection was analyzed in hybrid aedes albopictus cells formed by fusing ouabain-resistant cpe(+) cells to cpe(-) alpha-amanitin resistant cells. although the 24-h yields of virus from the parental cpe(+) and cpe(-) clones were similar, the rates of viral rna synthesis and virus release at early times post-infection were higher in the cpe(+) cells. in all eight hybrid clones studied, the cpe(+) phenotype was dominant. in addition, the kinetics of viral rna synthe ...19863765819
regional distribution of sindbis virus glycoproteins on the plasma membrane of infected baby hamster kidney cells.sindbis virus-infected baby hamster kidney (bhk) cells were analysed in surface replicas or conventional thin sections after specific immunolabelling with antiviral glycoprotein antibodies in conjunction with colloidal gold-conjugated protein a. newly synthesized viral glycoproteins were detected, beginning 1 1/2 h after infection, while the virus maturation started 3 h after infection. the glycoproteins appeared to be inserted on the plasma membrane in large spots located mainly in the central ...19873780874
[mechanism of action of remantadine hydrochloride on sindbis virus reproduction: inhibition of virus penetration into the cell].the effect of rimantadine and ammonium chloride on the rna synthesis of sindbis virus, added in different times of infection cycle, was studied. when compounds were presented in period of adsorption and first hour post-infection, the maximal inhibitory effect was found. the step blocked by rimantadine was identified as uncoating process (deprotainization). this connection was confirmed by the finding that rimantadine markedly reduced the change of the virus rna into the nuclease-sensitive form.19863811275
free diffusion to and from the inner nuclear membrane of newly synthesized plasma membrane glycoproteins.sindbis virus-infected baby hamster kidney (bhk) cells were analyzed by thin section fracture-label. specific immunolabel with antiviral glycoprotein antibodies was used in conjunction with colloidal gold-conjugated protein a. as we previously reported (torrisi, m. r., and s. bonatti, 1985, j. cell biol., 101:1300-1306), sindbis transmembrane glycoproteins are present in the inner nuclear membrane as well as in the outer nuclear membrane, endoplasmic reticulum, golgi stacks and vesicles, and pla ...19873818797
the t=4 envelope of sindbis virus is organized by interactions with a complementary t=3 capsid.the three-dimensional structure of sindbis virus, an enveloped animal virus, has been determined to a resolution of 35 a by using a common lines procedure to combine cryoelectron micrographs of vitrified particles. the spikes of the virus appear as columnar trimers arranged on a t=4 lattice. the lipid bilayer of the virus envelope is polyhedral and surrounds a smooth t=3 nucleocapsid. hence, a complete sindbis virion (molecular weight 46.4 x 10(6)) contains 240 copies of each of the spike protei ...19873829124
immunisation of cattle with a recombinant togavirus-vaccinia virus strain.genetic engineering techniques have been used to construct a vaccinia virus recombinant which contains and expresses togavirus (sindbis) genetic information. intradermal inoculation of this recombinant strain into calves caused a transient pock-type lesion at the site of inoculation and elicited the production of substantial levels of anti-sindbis virus neutralising antibodies. these results suggest that recombinant vaccinia virus vaccines may have potential for use in veterinary medicine.19853862196
cross-reactive target antigen in cell-mediated cytolysis of cells infected with a temperature-sensitive mutant of sindbis virus.cytotoxic t lymphocytes (ctl) against alphavirus-infected l929 cells were generated in mice by two in vivo immunizations of one virus or by in vivo immunization followed by in vitro stimulation of splenocytes with infected peritoneal exudate cells or splenocytes. these ctl caused specific h-2-restricted cytolysis equally well with homologous, heterologous or sindbis virus ts20 mutant-infected cells. thus, specific ctl appear to be cross-reactive components in normal immunity to alphaviruses and ...19853873514
sequence analysis of three sindbis virus mutants temperature-sensitive in the capsid protein autoprotease.we have cloned and sequenced the cdna made to the region of rna encoding the structural proteins of three complementation group c mutants of sindbis virus, ts2, ts5, and ts13, and of their revertants. these mutants possess defects in the posttranslational processing of their structural proteins at the nonpermissive temperature. comparison of the deduced amino acid sequences of the mutants with those of the revertants and with the parental hr strain of virus showed all three mutants to have singl ...19853895223
sensitive enzyme immunoassay for detecting immunoglobulin m antibodies to sindbis virus and further evidence that pogosta disease is caused by a western equine encephalitis complex antibody capture enzyme immunoassay (eia) was adapted for the detection of immunoglobulin m (igm) antibody to sindbis (sin) virus. sera from humans with a febrile illness characterized by rash and arthralgia in eastern finland (pogosta [pog] disease) and sweden (ockelbo disease) and from humans with western equine encephalitis (wee) virus infection in the united states were tested for igm antibodies by eia. seroconversions were documented in patients with pog disease and with wee virus infect ...19853908469
[single radial hemolysis of arboviruses]. 19853914374
characteristics of antiviral and anticellular activities of human recombinant interferon-gamma.the antiviral and anticellular activities of recombinant human interferon-gamma (re-ifn-gamma) were compared with those of natural human interferon-gamma (ifn-gamma), natural human interferon-alpha (ifn-alpha), and recombinant human interferon-beta (reifn-beta). reifn-gamma and ifn-gamma induced the antiviral state in fl cells against sindbis virus more rapidly than ifn-alpha or reifn-beta. the antiviral state induced by a short exposure time to ifn-gamma declined rapidly after the removal of if ...19853922841
inactivation of viruses in labile blood derivatives. ii. physical methods.the thermal inactivation of viruses in labile blood derivatives was evaluated by addition of marker viruses (vsv, sindbis, sendai, emc) to anti-hemophilic factor (ahf) concentrates. the rate of virus inactivation at 60 degrees c was decreased by at least 100- to 700-fold by inclusion of 2.75 m glycine and 50 percent sucrose, or 3.0 m potassium citrate, additives which contribute to retention of protein biologic activity. nonetheless, at least 10(4) infectious units of each virus was inactivated ...19853934802
sindbis virus-mediated cell fusion from without is a two-step event.the process by which sindbis virus induces the fusion of bhk-21 cells in monolayer cultures after exposure to low ph was examined. the fusion process was found to require an exposure to low ph followed by a return to conditions closer to neutral ph. the rate at which cells fused was affected by the ph to which the monolayers were exposed, subsequent to the initial exposure to acid conditions. virus-mediated cell fusion was not observed if the virus-cell complexes were maintained at the acid ph r ...19863944588
exclusion of superinfecting homologous virus by sindbis virus-infected aedes albopictus (mosquito) cells.the infection of tissue-cultured aedes albopictus (mosquito) cells by an alphavirus ultimately results in a persistently infected cell population which can be maintained in the laboratory for years. one characteristic of this culture is that it will not support the replication of superinfecting homologous virus. we have previously shown that mosquito cells persistently infected with sindbis virus produce an antiviral agent which when applied to uninfected mosquito cells suppresses sindbis virus ...19863951024
detection of immunologically cross-reacting capsid protein of alphaviruses on the surfaces of infected l929 cells.hyperimmune, but not normal immune, monospecific antiserum made to capsid protein of sindbis virus (sin) was found to cause cytolysis equally well of both sin- and semliki forest virus-infected l929 cells in antibody-dependent, complement-mediated cytotoxicity assays. the cell surface reactivity of the hyperimmune antiserum was also demonstrated by solid-phase radioimmune assays with unfixed infected cells or infected cells fixed with low concentrations of glutaraldehyde (0.025%) before reactivi ...19853965743
sindbis virus proteins nsp1 and nsp2 contain homology to nonstructural proteins from several rna plant viruses.although the genetic organization of tobacco mosaic virus (tmv) differs considerably from that of the tripartite viruses (alfalfa mosaic virus [almv] and brome mosaic virus [bmv]), all of these rna plant viruses share three domains of homology among their nonstructural proteins. one such domain, common to the almv and bmv 2a proteins and the readthrough portion of tmv p183, is also homologous to the readthrough protein nsp4 of sindbis virus (haseloff et al., proc. natl. acad. sci. u.s.a. 81:4358 ...19853968720
studies of defective interfering rnas of sindbis virus with and without trnaasp sequences at their 5' termini.three of six independently derived defective interfering (di) particles of sindbis virus generated by high-multiplicity passaging in cultured cells have trnaasp sequences at the 5' terminus of their rnas (monroe and schlesinger, j. virol. 49:865-872, 1984). in the present work, we found that the 5'-terminal sequences of the three trnaasp-negative di rnas were all derived from viral genomic rna. one di rna sample had the same 5'-terminal sequence as the standard genome. the di rnas from another d ...19853973983
genetic and antigenic variations among geographical isolates of sindbis virus.the genetic and antigenic variation in 12 sindbis (sin) virus isolates from four zoogeographic regions (paleoarctic, ethiopian, oriental and australian) has been examined at a molecular level. rnase t1 oligonucleotide fingerprinting of genomic rna from sin isolates revealed that the primary structure of the rna from viruses from each zoogeographic region was unique. the e1 and e2 glycoproteins and the capsid protein of two isolates from each zoogeographic region were compared by tryptic peptide ...19853981136
bhk cells expressing sindbis virus-induced homologous interference allow the translation of nonstructural genes of superinfecting virus.the process by which sindbis virus excludes superinfecting homologous virus was investigated with the use of temperature-sensitive mutants. mutants in two rna-negative complementation groups were found to be defective in their ability to establish interference at the nonpermissive temperature. these mutants were unable to establish interference in a mixed infection (complementation), suggesting that both were defective in a common gene product. homologous interference was found to block the repl ...19853989908
the ratio of plasma membrane cholesterol to phospholipid and the inhibition of sindbis virus maturation by low nacl medium.sindbis virus maturation is inhibited by low nacl medium in chick embryo cells and in one strain of bhk cells, but not in another strain of bhk cells which has a different passage history. the plasma membrane of the cells in which sindbis virus maturation is resistant to low nacl medium has a higher ratio of cholesterol to phospholipid than the other cells. cholesterol-containing liposomes, but not cholesterol-free liposomes, can release sindbis virus from low nacl-inhibited cells. these results ...19853998710
persistent infection of rabies virus (hep-flury strain) in human neuroblastoma cells capable of producing interferon.apparent interferon-mediated persistent infection of rabies virus (hep-flury strain) was established in a human neuroblastoma sym-i (clone k-104) cell line, which had the ability to produce interferon. this infection produced variable but small amounts of progeny virus and interferon (up to 100 iu/ml), and resisted superinfection with vesicular stomatitis virus (vsv) and sindbis virus as well as homologous rabies virus. the treatment of this infection with anti-interferon antibody stimulated vir ...19853998711
in vitro synthesis of the gene coding for the glycoprotein e1 of sindbis virus.ds cdna of the 42s virionic rna of sindbis virus has been synthesized and cloned in the plasmid pbr 322. restriction map analysis and hybridization studies show that two clones cover the 3' end non coding region of the rna, the whole membrane glycoprotein e1 and a peptide of mw 6,000 daltons. the use of these clones in experiments of gene expression in mammalian cell is discussed.19854010526
sindbis virus glycoproteins are abnormally glycosylated in chinese hamster ovary cells deprived of glucose.we have previously demonstrated that sindbis virus infection of chinese hamster ovary (cho) cells altered the protein glycosylation machinery of the cell, so that both normal, full-size (nine mannose-containing) oligosaccharides and abnormal, "truncated' (five mannose-containing) oligosaccharides are transferred from lipid-linked precursors to newly synthesized viral membrane glycoproteins. in the present studies, we have examined the precursor oligosaccharides on viral glycoproteins that were p ...19854020347
mrna activity of a sindbis virus defective-interfering rna.we obtained sindbis defective-interfering particles by nine and undiluted passages of standard virus on chicken embryo fibroblasts. these particles contain a deleted 20s rna molecule which has mrna activity, as shown by translation in cell-free systems in vitro. in infected cells, this mrna activity appeared to be totally inhibited except at very late times postinfection.19854020971
expression of sindbis virus structural proteins via recombinant vaccinia virus: synthesis, processing, and incorporation into mature sindbis virions.we have obtained a vaccinia virus recombinant which contains a complete cdna copy of the 26s rna of sindbis virus within the thymidine kinase gene of the vaccinia virus genome. this recombinant constitutively transcribed the sindbis sequences throughout the infectious cycle, reflecting the dual early-late vaccinia promoter used in this construction. the sindbis-derived transcripts were translationally active, giving rise to both precursor and mature structural proteins of sindbis virus, includin ...19854032536
rdb--a new product of plant origin for cell culture dispersion.rdb is a crude preparation extracted from a plant source. it is a very potent agent for dispersion of monolayer cell cultures as well as for the preparation of primary cell suspensions. it was found to be most effective in dispersing a wide range of animal and mosquito cells and dissociating neuronal and muscular tissue for primary cell cultures. rdb was also found to be useful for preparation of primary culture for chick embryo fibroblasts. after treatment with rdb cell viability was found to b ...19854043538
immunocytochemical study of the partition and distribution of sindbis virus glycoproteins in freeze-fractured membranes of infected baby hamster kidney cells.sindbis virus-infected baby hamster kidney cells were analyzed by thin section fracture-label. specific immunolabel with antiviral glycoprotein antibodies or with conventional lectin label (wheat germ agglutinin) were used in conjunction with colloidal gold-conjugated protein a or ovomucoid, respectively. in addition, intact infected cells were analyzed with both labeling procedures. experiments with sindbis infected-chick embryo fibroblast cells were carried out as controls. viral transmembrane ...19854044639
pattern of glycosylation of sindbis virus envelope proteins synthesized in hamster and chicken cells.the tryptic glycopeptides of the sindbis virus envelope glycoproteins e1 and e2 grown in bhk and chick cells were purified by gel filtration followed by high-pressure liquid chromatography. each of the purified glycopeptides was analyzed by n-terminal sequencing to identify from which of the potential glycosylation sites it was derived. the type of oligosaccharide chain attached to each glycopeptide was determined from gel filtration analysis of the pronase-digested glycopeptides, and the relati ...19854060569
functional analysis of the a complementation group mutants of sindbis hr virus.the 10 members of the a complementation group of temperature-sensitive (ts) mutants of sin hr, the heat-resistant strain of sindbis virus, were divided into two phenotypic subgroups. subgroup i mutants (ts15, ts17, ts21, ts24, and ts133) demonstrated temperature-sensitive 26 s mrna synthesis, whereas subgroup ii mutants (ts4, ts14, ts16, ts19, and ts138) did not; both ts4 and ts19 demonstrated defective 26 s mrna synthesis at 30 degrees. none of the a group mutants demonstrated temperature-sensi ...19854060589
sindbis virus mutants able to replicate in methionine-deprived aedes albopictus cells.previous work from this laboratory has shown that the replication of sindbis virus (sv) in aedes albopictus cells is sensitive to methionine withdrawal. this sensitivity is thought to reflect a diminished concentration of s-adenosylmethionine (ado met) resulting from methionine starvation. serial passage of sv on ae. albopictus cells maintained in low concentrations of methionine gave rise to a population of mutants whose replication in mosquito cells was resistant to methionine starvation. in v ...19854060595
expression of recombinant vaccinia virus-derived alphavirus proteins in mosquito cells.a recombinant vaccinia virus strain which contains and expresses a 26s cdna insert encoding sindbis virus structural proteins (vv:3s) was used to infect a continuous line of aedes albopictus mosquito cells. there were not visible cytopathic effects due to the virus infection and the cells continued to grow normally. however, examination of the proteins present in the cytoplasm of the infected cells with sindbis virus-specific antisera revealed that sindbis virus proteins were being synthesized a ...19854067584
use of chicken and rabbit antibodies in a solid phase protein a radioimmunossay for virus detection.a new rapid indirect solid phase radioimmunoassay was developed for the detection of sindbis virus. chicken antibodies were adsorbed onto wells in microplates to serve as 'capture antibodies' and rabbit antibodies were used as the second antibody. 125i-labelled protein a that does not bind to chicken antibodies, but binds firmly to rabbit antibodies was used as the tracer. all the steps necessary for the development of the assay are described. the minimal amount of sindbis virus detectable was a ...19854077951
the nonstructural proteins of sindbis virus as studied with an antibody specific for the c terminus of the nonstructural readthrough polyprotein.a dodecapeptide containing the sequence of the c terminus of the nonstructural polyprotein of sindbis virus has been synthesized and used to immunize rabbits. the antisera obtained precipitated polypeptides from cells infected with the hr strains of sindbis or with temperature-sensitive mutants ts11 or ts18. four different polypeptides, having apparent molecular weights of approximately 250,000, 220,000, 155,000, and 72,000, were immunoprecipitated by the antipeptide antiserum. the largest of th ...19854082500
[independence of interferon production from virus replication in the cell]. 19714101496
[biological study of the appearance of interferon action]. 19714101497
interferon and respiratory syncytial virus. 19714105357
biological, physical, and chemical properties of eastern equine encephalitis virus. i. purification and physical properties.a new purification procedure was adopted for eastern equine encephalitis virus which does not subject the virus to pelleting at any stage. three- to 4-liter volumes were passed through a diethylaminoethyl cellulose column. the virus-containing fractions were banded on a sucrose cushion and finally concentrated in an isopycnic band in a linear sucrose gradient. this method reduced the volume 1,000-fold with a concomitant increase in viral titer, i.e., better than 90% recovery. numerous criteria h ...19714106780
studies on the substructure of togaviruses. i. effect of urea, deoxycholate, and saponin on the sindbis virion. 19714107032
isolation of hemorrhagic nephroso-nephritis virus in cell cultures. 19714107353
phospholipid composition of rous sarcoma virus, host cell membranes and other enveloped rna viruses. 19714108030
studies on the nature of dengue viruses. v. structure and development of dengue virus in vero cells. 19714108617
use of chicken tracheal organ cultures for studying resistance of respiratory epithelium to viral infection. 19724110797
sindbis virus maturation. 19734121292
the production of antibody to hepatitis-associated antigen. 19724122067
glycoproteins as components of cellular membranes. 19734122628
inhibition of murine leukemia virus replication by poly(vinyluracil) and poly(vinyladenine).poly(1-vinyluracil) and poly(9-vinyladenine), as well as the corresponding polynucleotides poly(uridylate) and poly(adenylate), inhibit acute murine leukemia virus infection in mouse-embryo cells, but they do not significantly inhibit the replication of sindbis and vesicular stomatitis viruses. the polymers were most effective as inhibitors when added during an early stage of virus replication. effects of vinyl polymers on the rna-dependent dna polymerase from the virions of murine leukemia viru ...19734123932
effects of polyadenylic acids on functions of murine rna tumor viruses.single-stranded polyribonucleotides, which competitively inhibit murine rna tumor virus reverse transcriptase in vitro, were tested as inhibitors of various virus functions in cell culture. the compounds had two concentration-dependent effects. at high concentrations (100 mug/ml), both poly(adenylic acid) [poly(a)] and poly(2'-o-methyladenylic acid) [poly(am)] inhibited the uptake of radioactively labeled leukemia virus by swiss mouse embryo cells, but neither had a similar effect on sindbis vir ...19734128377
morphological variants of sindbis virus obtained from infected mosquito tissue culture cells.tissue-cultured aedes albopictus cells infected with morphologically homogeneous sindbis virus were found to produce progeny virions which could be divided into three classes based on size. the thickness of the envelope was constant on all three sizes of progeny virions suggesting that the variability in size rested with the viral nucleocapsid. it is suggested that the three classes of virions have icosahedral nucleocapsids composed of common subunits organized in decreasing triangulation number ...19734128381
antigenic components of group a arbovirus virions.three group a arboviruses, sindbis (sin), western (wee) and eastern equine encephalitis (eee), were selectively degraded with a nonionic detergent to yield a core particle and a soluble envelope component. antigenic analysis by using radioimmune precipitation techniques revealed marked antigenic similarity among the core particles of the three viruses. the soluble envelope component exhibited antigenic specificity similar to that of intact virions. a close relationship between sin and wee envelo ...19734128825
the effect of measles virus infection on t and b lymphocytes in the mouse. i. suppression of helper cell activity. 19744139203
[antibodies against arboviruses in starlings (sturnus vulgaris l.) in austria]. 19724145101
analysis of sindbis virus and its soluble antigens in preparations concentrated by precipitation with polyethylene glycol or ammonium sulfate. 19734148115
viral infection and resistance in immunosuppressed host. iv. abolition of potentiated togavirus a infection by a resistance inducer of the double-stranded rna type. failure of an exogenous interferon preparation. 19734148213
isolation of sindbis virus from the reed warbler (acrocephalus scirpaceus) in slovakia. 19734148218
influence of incubation temperaure on interferon mechanism in cells of testudo graeca kidney. 19734148898
comparative susceptibility of eight mosquito species to sindbis virus. 19744149270
interferon induction by, and antiviral effect of poly (ri)--poly (rc) in experimental viral infection. 19734150030
[survey with human sera from west cameroon (author's transl)]. 19734150072
field studies on the feeding habits of mosquitoes in the highveld region of south africa. 19734151015
evidence for circulation of sindbis virus and other arboviruses by using sentinel animals in western slovakia. 19734152182
haemagglutination-inhibiting antibodies to arboviruses in a human population in greece. 19744155197
studies on the nucleocapsid structure of a group a arbovirus.when sindbis virus (273s) was treated with sodium desoxycholate, a nonhemagglutinating 136s particle was liberated from the virion, representing the viral nucleocapsid (core). electron microscopically it appeared as a spherical particle 35 nm in diameter, showing ringlike morphological units 12 to 14 nm in diameter on its surface. when the one- and two-sided images of core particles were correlated, their structure could be demonstrated to have the t = 3 arrangement of 32 hexamer-pentamer morpho ...19694186278
immunochemical studies of sindbis virus variants. 19734197817
effects of actinomycin d and ultraviolet and ionizing radiation on pichinde virus.actinomycin d (0.05 mug/ml) suppresses the synthesis of ribosomal rna of baby hamster kidney (bhk21) cells. the production of infectious pichinde virus was enhanced in the presence of actinomycin d, although the production of virus particles was not substantially different from cultures inoculated in the absence of the drug. by prelabeling bhk21 cells with (3)h-uridine and then allowing the virus to replicate in the presence of actinomycin d, it was possible to show that ribosomal rna synthesize ...19734199107
[use of ultrasound for increasing the activity of arbovirus antigens in serological reactions in vitro]. 19734203622
[study of chronic forms of arbovirus infections in birds. 1. experiments with west nile, sindbis, bhandja and sicilian mosquito fever viruses]. 19734204261
biological and physical properties of the suckling mouse cataract agent grown in chicken embryos.experiments were carried out with the suckling mouse cataract agent (smca) in an attempt to better characterize the nature of this agent. despite the fact that high titers of smca were found in the chorioallantoic fluid of inoculated chicken embryos, the agent did not replicate in chicken embryo epithelial cell cultures. smca did not interfere with sindbis virus plaque formation and was not inhibited by chicken interferon or polyinosinic-polycytidylic acid. the agent was relatively resistant to ...19744205951
host dna synthesis-suppressing factor in culture fluid of tissue cultures infected with measles dna synthesis is suppressed by the culture fluid of cell cultures infected with measles virus. this activity in the culture fluid is initiated somewhat later than the growth of infectious virus. ninety percent of host dna synthesis in hela cells is inhibited by culture fluid of 3-day-old cell cultures of vero or hela cells infected with measles virus. this suppressing activity is not a property of the virion, but is due to nonvirion-associated component which shows none of the activities of ...19744207526
[animal experiments on the effect of viruses on wound healing (author's transl)]. 19744211298
biochemical studies on degenerative neurological disorders. i. acute experimental encephalitis. 19744211835
structural and immunologic characteristics of subviral components of sindbis, eastern equine and western equine encephalitis viruses. 19724212354
[changes in the properties of sindbis virus during passage experiments in "drosophila" (author's transl)]. 19734214134
arthropod-borne viruses in australia and their relation to infection and disease. 19744214338
[interaction of poly i-c with membranes of cells stimulated to produce interferon and of cells not so stimulated]. 19744219771
[effects of actinomycin d and of rubidomycin on the replication of sindbis virus]. 19684238181
[comparative study of the action of propylene glycol and dimethylsulfoxide on various "virus-host" systems]. 19714253513
[detection of antibodies to a series of arboviruses of groups a, b and bunyamwera on the territory of the georgian ssr]. 19724260426
a case of sindbis virus infection in kuala lumpur. 19724268041
inhibition of sindbis virus plaque formation by extracts of escherichia coli.vilcek, jan (new york university school of medicine, new york, n.y.), and john h. freer. inhibition of sindbis virus plaque formation by extracts of escherichia coli. j. bacteriol. 92:1716-1722. 1966.-extracts prepared from washed cells of escherichia coli b by sonic treatment and subsequent filtration through a 0.45-mu membrane filter significantly inhibited plaque formation with sindbis virus in cultures or primary chick embryo cells up to a dilution of 1:20,000. the inhibitor acted on the cel ...19664289359
inhibition of antibody production in rats and mice by intravenous injection of interferon-inducing amounts of sindbis virus or e. coli. 19674299725
differences between the structures of poliovirus and sindbis virus infectious ribonucleic acids. 19674299727
plaque variants by sindbis virus. 19674301200
inhibition of sindbis virus production by media of low ionic strength: intracellular events and requirements for reversal.incubation of sindbis virus-infected cultures in medium with an ionic strength of 0.105 reduced the virus yield more than 99%. this inhibition was rapidly reversed by exposing the cultures to normal medium: within 20 min the previously inhibited cultures had released as much infectious virus as normal controls had produced during hours of incubation. the following intracellular processes were essentially normal in inhibited, infected monolayers: protein and phospholipid synthesis, the synthesis ...19704315161
effect of persistent fibroma virus infection on susceptibility of cells to other viruses.shope fibroma virus establishes a persistent cytoplasmic infection in primary (rk) and serially cultivated (drk(3)) rabbit kidney cells which is accompanied by a morphological alteration of the cells. the response of such cells to superinfection by other viruses was compared with that of control cells by determining plaque production and virus yield of superinfecting viruses. it was found that the growth of other poxviruses, myxoma and vaccinia, was greatly inhibited in the fibroma virus-infecte ...19704317346
intrinsic interference: a new type of viral interference.the hemadsorption-negative plaque test has revealed a new type of viral interference, termed intrinsic interference. several unrelated types of noncytopathic viruses were shown to induce in infected host cells a state of interference unique in being directed solely against superinfection by newcastle disease virus (ndv). the ndv-refractory state arises only in those individual cells of a population actually infected by the inducing virus, and presumably results from the action of a protein(s) co ...19674318951
comparison of membrane protein glycopeptides of sindbis virus and vesicular stomatitis virus.a comparison has been made of the membrane glycoproteins and glycopeptides from two enveloped viruses, sindbis virus and vesicular stomatitis virus (vsv). glycopeptides isolated from sindbis virus and vsv grown in the same host appear to differ principally in the number of sialic acid residues per glycopeptide; when sialic acid is removed by mild acid treatment, the glycopeptides of the two viral proteins are indistinguishable by exclusion chromatography. preliminary evidence argues that the car ...19704322870
effect of antilymphocytic serum on circulating interferon in mice as a function of the inducer. 19714325471
the formation of interferon during acute respiratory virus infection of volunteers. 19714325979
[interferon production stimulation in the white mouse by dimethylsulfoxide (dmso)]. 19714326011
virus interference by cellular double-stranded ribonucleic acid.ribonuclease-resistant ribonucleic acid (rna) was isolated from uridine-labeled cultures of rabbit kidney, chicken embryo, and hela cells. this rna, regardless of its source, was found to induce interference with virus growth in either rabbit kidney or chicken embryo cultures. nuclease-treated cellular nucleic acids exhibited interference-inducing activity which eluted with a small fraction of rna in the exclusion volume of a 6% agarose gel column. besides resistance to ribonucleases, the interf ...19714327582
inhibition of interferon synthesis in phospholipase c treated primary chick embryo cells. 19714327713
homologous interference by incomplete sendai virus particles: changes in virus-specific ribonucleic acid synthesis.incomplete sendai virus particles (i particles) interfered with the replication of several strains of infectious sendai virions (standard virus) but not with the replication of newcastle disease virus, mumps virus, or sindbis virus. i particles did not induce interferon, and ultraviolet irradiation of i particles abolished their ability to interfere. protein synthesis was not necessary to establish interference. the degree of interference depended on the interval between exposure of cells to the ...19714331647
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