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paramagnetic spin label interactions with the envelope of a group a arbovirus. lipid organization.electron paramagnetic resonance observations were made on nitroxide spin- labeled molecules which were bound to the tc-83 vaccine strain of venezuelan equine-encephalomyelitis virus. paramagnetic resonance parameters derived from the observations and their dependence on sample temperature were similar but not identical to those which have been reported for these labels dissolved in lipid bilayer membranes of mammalian and bacterial origin. the data has a mechanical rigidity substantially greater ...1975166687
inhibition of interferon action by chinoform.chinoform, iodochlorhydrozyquin, was found to suppress the antiviral action of interferon. chick embryo fibroblast cells treated with the mixture of interferon and chinoform were more sensitive to sindbis virus infection than cells treated with interferon alone. no evidence for a direct inactivation of interferon molecule by chinoform was obtained. treatment with chinoform of cells previously exposed to interferon also removed a cellular antiviral state induced by interferon. chinoform suppresse ...1979158703
eukaryotic mrna cap binding protein: purification by affinity chromatography on sepharose-coupled m7gdp.a 24,000-dalton polypeptide that binds strongly and can be specifically crosslinked to the 5'-terminal cap structure m7gpppn in eukaryotic mrnas has been detected in protein synthesis initiation factor preparations [proc. natl. acad. sci. usa (1978) 75, 4843--4847]. this polypeptide has been purified to apparent homogeneity by one chromatographic passage through an affinity resin prepared by coupling the levulinic acid o2',3'-acetal of m7gdp to ah-sepharose 4b. translation, in hela cell extracts ...1979291969
use of polyethylene glycol-treated calf serum for cell cultures in virus and interferon studies.immunoglobulins and lipoproteins can be efficiently removed from calf serum by precipitation with polyethylene glycol (peg) 6000 under sterile conditions. the peg-treated serum is suitable for cell cultures used for virus growth and assays. moreover, peg was found to slow down the growth of l cells and to enhance the production and activity of mouse interferon.197550724
in vitro heterologous cytotoxicity by t effector cells from mice immunized with sindbis virus.an in vitro correlate of cell-mediated cross-protection among alpha-viruses was demonstrated by cytotoxicity of sindbis-immune spleen cells from mice to both sindbis and semliki forest virus (sfv)-infected target cells. this cytotoxicity was shown to be mediated by the t cell population of the spleen and was independent of the presence of macrophages or b cells. the time when the level of the lymphocyte-mediated cytotoxicity (lmc) to sfv-infected cells was maximal coincides with the time when im ...1979314471
the specificity and applications of antibodies to helical nucleic acids. 197550162
envelope antigens of sindbis virus in cells infected with temperature-sensitive mutants.indirect fluorescent-antibody studies of living and fixed chick cells infected with temperature-sensitive mutants of sindbis virus suggest that functional envelope glycoprotein e1 must be inserted through the plasma membrane before e2. pe2 and e2 do not affect the insertion of e1. the experiments also suggest that normal pe2, a glycosylated precursor to e2, reacts with anti-e2 serum; the abnormal pe2 made by a temperature-sensitive pe2 cleavage-defective mutant did not. abnormal e1 proteins made ...1977319257
immunoferritin studies on the multiplication of sindbis virus in chick embryo fibroblasts.replication of sindbis virus chick embryo fibroblasts was studied by means of the immunoferritin technique. virus specific antigens, diffusely distributed in the cytoplasm, were observed at first 3 hours p.i. at the same time in ohter cells ferritin particles in linear arrangement occured at the surface of vesicles. at these places heavily labelled nucleocapsids were observed later on. this means, that the surface of vesicles is a site of assembly of nucleocapsids. maturation of virus takes plac ...1977325950
[antiviral immunity in insects]. 1977332038
[interaction of the sindbis virus and rauscher and friend leukoviruses in primary cultures and subcultures of mouse fibroblasts in the early stages of persistence].the interaction between friend and raucher leukoviruses and sindbis togavirus was studied in primary cultures of mouse fibroblasts and subcultures passaged for 77 days. in primary cultures, two types of virus interactions were observed: neutralism and interference. in interference, the release of the infectious sindbis virus from the cells is blocked. according to electron microscopic observations, its reproduction terminates by formation of virus nucleocapsid. the blocking of the togavirus matu ...1977333760
detection of antibodies to alphaviruses by enzyme-linked immunosorbent assay.cell culture-derived antigens detected antibodies to alphaviruses in human sera with the enzyme-linked immunosorbent assay technique. results correlated with those from hemagglutination inhibition and neutralization tests.1979393723
purification and electron microscopy of lactic dehydrogenase virus of mice.lactic dehydrogenase virus (ldv) was purified from infectious ascites fluid of mice bearing ehrlich tumours using sepharose gel filtration and rate zonal and isopycnic sedimentation. in glycerol gradients, a sedimentation coefficient of about 200s and a buoyant density of 1-14 g/ml was determined for the virus particle. spherical particles with diam. between 62 and 80 nm, depending on the method of fixation and staining, have been identified electron microscopically. the virus particle consists ...197547383
haemolysis by two alphaviruses: semliki forest and sindbis virus.purified preparations of semliki forest (sfv) and sindbis virus haemolyse red blood cells from several species of animals and birds. the optimal haemolysis by sfv was obtained at ph 5.8 with 1-day-old chick erythrocytes incubated at room temperature. considerable variation in haemolytic activity was observed between different virus preparations purified by different methods. the haemolytic activity of sfv was inhibited by antisera against whole virus or isolated envelope proteins but not with an ...197939116
glycosidase susceptibility: a probe for the distribution of glycoprotein oligosaccharides in sindbis virus.intact sindbis virus and triton-solubilized viral glycoprotein were treated with alpha-mannosidase and with a preparation of mixed glycosidases from diplococcus pneumoniae to probe the accesibility of carbohydrate units on the viral surface. the products of glycosidase attack on triton-solubilized virus showed that mose carbohydrate units of the glycoproteins are good substrates for these enzymes. the relative resistance of most of the viral oligosaccharides in intact virus particles showed that ...197718614
growth medium utilization and its re-use for animal cell cultures. 197714164
oligonucleotide mapping studies of standard and defective sindbis virus rna.oligonucleotide mapping studies of the rna from standard and defective interfering particles of sindbis virus demonstrate that 3'- and 5'-terminal regions of the genome are conserved in the defective rnas. these studies also suggest that defective rnas contain multiple deletions.1979430611
the dynamics of development of cell resistance to viruses induced by synthetic polynucleotides.the dynamics of interaction of complexes of synthetic polynucleotides (polyinosinic and polycitidylic acid--poly (ri)-poly (rc), and polyguanylic and polycytidylic acid--poly (rg)-poly (rc)) with cells as well as the dynamics of interferon accumulation and development of antiviral effect against some rna viruses were studied in primary chick embryo cell (cec) cultures. four phases were observed in the development of the antiviral effect of synthetic polynucleotides: adsorption, increase, marked ...19767937
biological activity of sera obtained by hyperimmunizing rabbits with interferon from mouse l cells.rabbits immunized with interferon from mouse l cells for long periods of time produced interferon-neutralizing antibodies with titers from 1:80 to 1,2000. the anti-interferon sera also contained antibodies against antigens contaminating the interferon preparations such as albumin, bovine gamma-globulin, chicken albumin, extract from l cells, and sindbis virus antigens. some sera also displayed cytotoxic activity against cells of transplantable murine leukemia. these antibodies could be removed b ...1979444043
serologic examination of human population in south moravia (czechoslovakia) on the presence of antibodies to arboviruses of the alfavirus, flavivirus, turlock groups and bunyamwera supergroup.a statistically representative group of human population from the south moravian region (cssr) was examined on the presence of antibodies against the following arboviruses: lednice, sindbis, tick-borne encephalitis, west nile, tahyna and calovo. the ascertained absence of antibodies to the lednice virus is an evidence that at present this virus is of no epidemiological importance in the region studied. no antibodies to sindbis, west nile and calovo viruses were demonstrated. 17.8 to 42.0% of ant ...1979447128
host defenses in herpes simplex infections of the nervous system: effect of antibody on disease and viral spread.balb/c mice passively immunized with antibody to herpes simplex virus type 1 and challenged in the footpad with 10(5.7) plaque-forming units of herpes simplex virus type 1 were shown to be protected from neurological disease and death compared with control mice treated with normal serum or antibody to sindbis virus. one hundred percent of untreated mice had virus recoverable from dorsal root ganglia by 48 h after infection. whereas amputation of the infected limb at 48 h had no effect, antibody ...1979217828
two small virus-specific polypeptides are produced during infection with sindbis virus.we have identified and characterized two small virus-specific polypeptides which are produced during infection of cells with sindbis virus, but which are not incorporated into the mature virion. the larger of these is a glycoprotein with an approximate molecular weight of 9,800 and is found predominantly in the medium of infected cells. three independent lines of evidence demonstrate conclusively that this 9,800-dalton glycoprotein is produced during the proteolytic conversion of the precursor p ...1979448798
studies on the morphology of alphaviruses. 1979462801
na+ and k+ concentrations and the regulation of protein synthesis in sindbis virus-infected chick cells. 1979462804
effect of incubation time on the generation of defective-interfering particles during undiluted serial passage of sindbis virus in aedes albopictus and chick cells. 1979462807
[accelerated method of determining the antiviral activity of interferon inducers in experimental infection].by the example of trials of two typical interferon inducers: a double-stranded complex of synthetic polyribonucleotides poly (i).poly (c) and polyacrylic acid the use of the proposed rapid method for the determination of the antiviral activity of interferon inducers in an experimental infection of mice with an alphavirus is described. the method permits to perform a statistically treated evaluation of the antiviral effect of a group of preparations within 96 hours. the mean standard error of the ...1979462928
the pathogenesis of sindbis virus infection in athymic nude mice. 1979469246
murine interferon system regulation: isolation and characterization of a mutant 3t6 cell engaged in the semiconstitutive synthesis of interferon.we describe the isolation and characterization of a virus-resistant mutant of murine 3t6 cells. the mutant, designated 3t6-vrb2, displays a high degree of resistance to infection by members of the toga-, rhabdo- and picornavirus classes. the level of this resistance to infection is similar to the parent 3t6 pretreated with approximately 100 lu/ml of interferon. upon co-cultivation of 3t6-vrb2 cells with interferon-sensitive mouse cells, an antiviral state is induced in the latter cells as measur ...1978208779
[interferonogenic activity of gossypol, a low-molecular substance].the interferonogenic activity of gossipol, a low molecular substance of polyphenolic nature was shown in the cell cultures of chick embryos and organisms of mice. pronounced prophylactic efficiency of the drug in mice with experimental infection caused by the west nile virus was found. definite parallelism between the intensity of interferonogenesis and the protection level from the virus affection due to the use of gossipol in mice was noted. difference between gossipol and other known low mole ...1978206198
[potential virostatics. 1. quinoxalines]. 1977203954
[antiviral effects of alpha-trihalogenomethylamines and their derivatives]. 1977202821
heterologous interference in aedes albopictus cells infected with alphaviruses.maximum amounts of 42s and 26s single-stranded viral rna and viral structural proteins were synthesized in aedes albopictus cells at 24 h after sindbis virus infection. thereafter, viral rna and protein syntheses were inhibited. by 3 days postinfection, only small quantities of 42s rna and no detectable 26s rna or structural proteins were synthesized in infected cells. superinfection of a. albopictus cells 3 days after sindbis virus infection with sindbis, semliki forest, una, or chikungunya alp ...1979480461
the extreme 5'-terminal sequences of sindbis virus 26 and 42 s rna. 1979483569
differential effects of ouabain on host- and sindbis virus-specified protein synthesis. 1979494493
the effect of membrane-active agents on sindbis virus morphogenesis.in chicken cells infected by sindbis virus and exposed to a variety of membrane-active compounds, virus release was inhibited. in infected cells exposed to antiserum directed against the virion glycoproteins e1 or e2, retinol, cortisone, pb++ or insulin, the processing of two sindbis virus precursor polypeptides which lead to the formation of virion polypeptides was inhibited. the b-protein, which is the precursor to both envelope proteins, accumulated in cells treated by these compounds. this p ...1979500330
absence of a cleavable signal sequence in sindbis virus glycoprotein pe2.partial nh2-terminal sequence analysis has been performed on some products that result from the translation of 26 s mrna of sindbis virus either in vivo or in vitro. in vivo products were obtained after pulse-labeling of virus-infected cells. in vitro products were obtained after cell-free translation either in the absence or presence of microsomal membrane vesicles from dog pancreas. the sequence data indicate that the selective translocation across the microsomal membrane required for a distin ...1979500711
interferon induction by viruses. ii. sindbis virus: interferon induction requires one-quarter of the genome--genes g and a.we have measured the amounts of interferon formed by chick cells 'aged' in vitro in response to different amounts of infectious wild-type sindbis virus. our results suggest that one plaque-forming unit is enough to induce maximum interferon formation. with higher m.o.i. the yield of interferon is less. to inactivate the interferon-inducing activity of sindbis virus, four times more u.v.-radiation was needed than to inactivate the infectivity of the virus. this suggests that only 25% of the virus ...1979501335
[change in the nature of the persistence of alpha- and flaviviruses in the body of balb/c strain mice with a mixed infection with leukovirus].the features of pathogenesis of infection caused in adult balb/c mice intraperitoneally infected with sindbis virus, virulent or attenuated strains of west nile (wn) virus, individually or in combination with rauscher leukemia virus (rlv) were studied. the influence of the latter on the course of togavirus infections was characterized by 3 features: (a) different effects on the visceral and neural phases of the pathogenesis (increased period of viremia and virus reproduction in the viscera did n ...1979506204
adjuvant polyarthritis. iii. evidence in support of viral etiology.intraperitoneal administration of a relatively small volume (0.2 ml) of plasma obtained from sindbis virus--infected animals containing approximately 480 units of interferon/ml effectively suppressed the development of adjuvant arthritis. similarly, administration of interferon (624 units/rat/day, ip) prepared in vitro by exposing rat embryo fibroblast culture to poly i:c in the presence of cycloheximide also suppressed the development of adjuvant arthritis without affecting the humoral or the c ...1977200247
viral receptors and their role in host and tissue specificity. 1975197866
establishment of persistent infection in bhk-21 cells by temperature-sensitive mutants of sindbis virus.twelve temperature-sensitive (ts) mutants of sindbis were examined for their ability to establish persistent infection in bhk-21 cells at 39 degrees c. five of these mutants were able to initiate colony formation in infected cultures, which followed an extensive c.p.e. two of the mutants were able to establish persistent infections which survived beyond the fifth cell passage p.i. the ability to initiate colony formation was correlated with low reversion of the ts mutation, or with ability to in ...1979521804
virulence of temperature-sensitive mutants of sindbis virus in neonatal mice.the virulence in neonatal mice of temperature-sensitive (ts) mutants of sindbis virus was determined by measurements of mean survival time and 50% lethal dose after intracerebral injection. for 11 ts mutants, mean survival time was determined by the ribonucleic acid (rna) phenotype, rna+ mutants killing the mice sooner than rna- mutants for the same titer of virus injected. mortality caused by seven ts mutants was, with one exception, correlated with the proportion of revertants recovered after ...1979528057
integration of genomes on infectious viruses.the article contains a review relating to the integration of genomes of infectious viruses in eukaryotic cells. data are presented that were obtained in the study of tissue cultures chronically infected with viruses, in the study of pathologic and ecologic processes. based on the evidence accumulated, some theoretical and applied aspects of the problem are discussed.1977194142
homologous interference induced by a temperature-sensitive mutant derived from an hvj (sendai virus) carrier culture.homologous interference between a temperature-sensitive small plaque mutant (hvj-pb) derived from an hvj (haemagglutinating virus of japan - the sendai strain of parainfluenza i virus) carrier culture of bhk cells and the original wild-type virus (hvj-w) has been investigated. prior infection of llcmk2, hela, bhk or mouse l cells with hvj-pb, both at permissive and non-permissive temperatures, for 24 h resulted in a reduced yield of superinfecting hvj-w, reflecting a smaller number of cells capa ...1976186564
infections in sentinel pigeons by sindbis and west nile viruses in south africa, with observations on culex (culex) univittatus (diptera: culicidae) attracted to these birds. 1979537007
functional defects of rna-negative temperature-sensitive mutants of sindbis and semliki forest viruses.defects in rna and protein synthesis of seven sindbis virus and seven semliki forest virus rna-negative, temperature-sensitive mutants were studied after shift to the restrictive temperature (39 degrees c) in the middle of the growth cycle. only one of the mutants, ts-6 of sindbis virus, a representative of complementation group f, was clearly unable to continue rna synthesis at 39 degrees c, apparently due to temperature-sensitive polymerase. the defect was reversible and affected the synthesis ...1979541824
restricted replication of two alphaviruses in ricin-resistant mouse l cells with altered glycosyltransferase activities.two mouse l cell variant lines (cl 3 and cl 6) selected for resistance to the toxic plant lectin ricin were restricted in their ability to replicate the two alphaviruses sindbis virus and semliki forest virus. cl 3 cells have been shown to exhibit increased cmp-sialic acid:glycoprotein sialyltransferase and gm3 synthetase activities, whereas cl 6 cells have been shown to contain decreased udpgalactose:glycoprotein galactosyltransferase and udp-n-acetylglucosamine:glycoprotein n-acetylglucosaminy ...1979219229
synthesis of sindbis virus nonstructural polypeptides in chicken embryo fibroblasts.the identification of eight previously undescribed polypeptides in chicken embryo cells infected with sindbis virus is reported. seven of these polypeptides were distinguishable from the virus structural polypeptides and their precursors by their molecular weights and tryptic peptide maps. the eighth was closely related to pe2 (schlesinger and schlesinger, 1973), a precursor to one of the virus particle glycoproteins. pulse-chase experiments and the use of an inhibitor of proteolytic cleavage al ...1977559103
virus-directed post-translational cleavage in sindbus virus-infected cells.the viral polypeptides synthesized in cells coinfected with group c and group d or e sindbis virus mutants were studied. cleavage of the ts2 protein occurs in cells coinfected with ts2 and ts20. since the ts2 protein fails to chase in cells infected with ts2 alone, the activity effecting this cleavage must be, at least in part, virus specified.1977559105
role of extracellular virus on the maintenance of the persistent infection induced in aedes albopictus (mosquito) cells by sindbis virus.sindbis virus infection of cultured mosquito cells was found to have no effect on the growth of these cells; instead, a persistent infection of the culture followed an initial acute phase of rapid virus synthesis. nearly all of the cells in the acute stage of infection were found to actively release virus in an infectious-center assay and to contain significant amounts of virus antigen as determined by immunofluorescence. cells in the persistent phase of infection released few virions into the m ...1977561193
arrangement of glucose residues in the lipid-linked oligosaccharide precursor of asparaginyl oligosaccharides.the lipid-linked oligosaccharide synthesized in vitro, in the presence of 1.0 microm udp-[3h]glc, gdp-[14c]man, and udp-glcnac has been isolated and the structure of the oligosaccharide has been analyzed. the oligosaccharide contains 2 n-acetylglucosamine, 9 mannose, and 3 glucose residues. the n-acetylglucosamine residues are located at the reducing terminus. the 3 glucose residues are arranged in a linear order at one of the nonreducing termini in the sequence glc 1,2--glc 1,3--glc--(man)9 (gl ...1979220251
synthesis and processing of protein-linked oligosaccharides in vivo. 1979220252
[viral interaction with stimulated and nonstimulated human tonsil cells].interferon induction and the course of infection with paramyxovirus (newcastle disease virus) and alphaviruses (venezuelan equine encephalomyelitis, sindbis, semliki forest viruses) in human tonsillar cell cultures were studied in comparison with continuous burkitt lymphoma, raji, and nawalva cells. the virus inducers stimulated production of dozens and hundreds iu50/ml of interferon in tonsillar cell cultures. no virus replication could be detected either in intact or phytohemagglutinin-stimula ...1979230646
[inhibition of vaccinia, sindbis and para-influenza virus replication by isatin beta-thiosemicarbazone derivative and methisazone in vitro and in vivo]. 1979232050
human arthropod-borne virus infections in nigeria. serological and virological investigations and shaki, oyo state.during the early dry season of 1972, an arbovirus surveillance was carried out is shaki. on hundred and twenty human blood samples and 304 sera were processed for virus isolation and serology respectively. a high prevalence of antibodies to 8 arbovirus antigens was found in the community. percentage of positive sera was as follows: chikungunya (24%) sindbis (19%), yellow fever (55%), dengue (54%), west nile (58%) and wesselsbron (67%). human infections by ilesha virus (35%) and ingwavuma (15%) ...1978570581
the outer boundary of the cytoskeleton: a lamina derived from plasma membrane proteins.we prepared the cytoskeletal framework by gently extracting cells with triton x-100. lipids and soluble proteins were removed, leaving a complex meshlike structure which contains the cell nucleus and is composed of the major cell filament networks as well as the microtrabeculae with attached polyribosomes. the surface sheet or lamina covering this structure contains most of the cell surface proteins by the following criteria. intact cells are labeled externally with radioiodine and then extracte ...1979573666
togavirus rna: reversible effect of urea on genomes and absence of subgenomic viral rna in kunjin virus-infected cells.electrophoretic analyses showed that no rnase-sensitive rna smaller than the genome was specified by the flavivirus kunjin in infected vero cells during the period of maximum rna and protein synthesis. in contrast, rna extracted from sindbis virus-infected cells under similar conditions included the expected 42s rna (equivalent to the genome) and the smaller 26s (interjacent) rna. treatment of the genome of both togaviruses with 12 m urea produced a reversible (possibly conformational) change; m ...1977597036
double-stranded complex of polyguanylic and polycytidylic acids and its antiviral activity in tissue culture.the antiviral activity and conditions of formation of the most active double-stranded complexes of synthetic homopolynucleotides, polyriboguanylic and polyribocytidylic acids, were studied on the model of primary trypsinized chick embryo cells and rna-containing viruses. the (poly g).(poly c) complex was very active against the viruses tested; their replication in cell cultures was inhibited completely. the antiviral activity of the (poly g).(poly c) complex increased markedly in the presence of ...1975239557
amino-terminal sequence analysis of the structural proteins of sindbis virus.the structural proteins of sindbis virus, an enveloped virus which belongs to the togavirus family, have been subjected to automated edman degradation using improved techniques. extensive nh2-terminal sequences of about 50 residues were determined for each of the two membrane glycoproteins. in both cases the nh2 terminus of the molecule was found to be similar in composition to typical water-soluble proteins. the viral capsid protein was found to have a blocked alpha-amino group. this is consist ...1978275841
susceptibility of chick neural retina to viral multiplication in vitro during embryonic development.decrease in the susceptibility of embryonic chick neural retina cultures to the multiplication of various viruses was observed with increasing age of the embryo. in contrast the retinal cells supported the multiplication of sindbis virus irrespective of the age when they were infected with the viral rna. these results suggest that the restricted multiplication of the viruses observed is due to the modulated inability of the cell to process the adsorbed viruses for subsequent replication.1978620735
reversible inhibition of sindbis virus penetration in hypertonic medium.under hypertonic conditions, the penetration of baby hamster kidney cells by sindbis virus was inhibited. virus became cell associated, but remained susceptible to neutralization by specific antiserum and to removal by elution. when cells were returned to isotonicity, inhibition was reversed.1978621783
synthesis of alphavirus-specified rna.uv irradiation of chicken fibroblasts infected with semliki forest or sindbis virus has been used to investigate the mechanism of synthesis of 42s and 26s rna, the major plus-strand virus-specified rnas formed during the multiplication of standard virus particles. from an analysis of the kinetics of uv inactivation of the synthesis of these two rnas, we conclude (i) that 26s rna is formed by internal transcriptive initiation from a point about two-thirds of the way from the 3' end of the 42s neg ...1978625087
adaptation of an aedes aegypti mosquito cell line to growth at 15 degrees c and its response to infection by sindbis virus.aedes aegypti mosquito cells, usually cultured at 28 to 30 degrees c, were adapted to grow at 15 degrees c. they were designated a. aegypti (c) cells, and had an estimated doubling time of 10 days. sindbis virus (sv) replicated in these cells to peak titres of over 1.0 x 10(9) p.f.u./ml 8 to 10 days after inoculation. these, or about 10-fold lower titres, continued to be produced over a 130 day test period without causing visible cell damage. continuous virus proliferation and the yield of unifo ...1978627872
evidence for covalent attachment of fatty acids to sindbis virus glycoproteins.selective binding of lipid to glycoprotein was detected when [3h]palmitate-labeled sindbis virus particles or viral-infected cells were disrupted by heating with sodium dodecyl sulfate, and glycoproteins were isolated by electrophoresis in sodium dodecyl sulfate/10% polyacrylamide gels. the smaller glycoprotein (e2) retained 2 to 3 times more labeled lipid than did the larger ei glycoprotein, and the cell-associated glycoprotein precursor (pe2) bound even less lipid. no lipid was associated with ...1979287008
interactions between immune cells and antibody in protection from fatal sindbis virus encephalitis.transfer of anti-sindbis virus serum, obtained from peripherally inoculated donors, protected mice from an otherwise fatal intracerebral infection with neuroadapted sindbis virus (nsv). f(ab)'2 preparations of serum were not protective, indicating that the fc piece of immunoglobulin g was important. complement-depleted animals were protected with anti-nsv serum, ruling out as essential the complement-fixing function of the fc piece. the presence of protective antibody correlated with the ability ...1979311344
cross protection among togaviruses in nude mice and littermates.after immunization with sindbis virus, t-cell deficient nude mice, compared to normal littermates, were equally protected against challenge with sindbis virus. however, the nude mice showed about one-tenth the protection observed with normal littermates after challenge with semliki forest virus at a dose of 100 ld50. this consistent with our previous interpretation that sensitized t-cell populations play a major role in cross protection between the two togaviruses. the remaining low level of spe ...1979316446
requirement of cell nucleus for african swine fever virus replication in vero cells.the role of the cell nucleus in the development of african swine fever virus in vero cells has been studied. no viral growth could be detected in enucleated cells under conditions that allow normal development of sindbis virus. furthermore, african swine fever virus dna synthesis was inhibited more than 95% after infection of enucleated vero cells as compared with normal cells.1977403300
the initial glycosylation of the sindbis virus membrane proteins.the mechanism by which the membrane proteins of sindbis virus are initially glycosylated during growth of the virus in chick cells was studied. the experiments suggest strongly that the 2 viral glycoproteins are glycosylated before release from the polysome and that this glycosylation involves transfer of a large, 1,800 dalton oligosaccharide to the polypeptide chains. the donor of the oligosaccharide is most probably a lipid.1978662921
replication of sindbis virus. vi. poly(a) and poly(u) in virus-specific rna species. 1978664244
sindbis envelope proteins as endogenous acceptors in reactions of guanosine diphosphate-[14c]mannose with preparations of infected chicken embryo fibroblasts.preparations of sindbis-infected chicken embryo fibroblasts incubated with gdp-[14c]mannose and udp-n-acetylglucosamine catalyze the glycosylation of endogenous phospholipids and membrane-associated proteins. the proteins are identified as the viral envelope proteins by precipitation with anti-sindbis antiserum, by comparison with authentic virion glycoproteins on sodium dodecyl sulfate-poly-acrylamide gel electrophoresis, and by comparison of the glycopeptides of the membrane-associated glycopr ...1977404295
[arbovirus multiplication is mosquito cells treated with an interferon inducer]. 1978695524
local resistance of chicken respiratory tract to viral infections. 1978696080
membrane biogenesis. in vitro cleavage, core glycosylation, and integration into microsomal membranes of sindbis virus glycoproteins.sindbis virus 26s rna has been translated in a cell-free protein-synthesizing system from rabbit reticulocytes. when the system was supplemented with edta-stripped dog pancreas microsomal membranes, the following results were obtained: (a) complete translation of 26s rna, resulting in the production, by endoproteolytic cleavage, of three polypeptides that are apparently identical to those forms of c, pe2, and e1 that are synthesized in vivo by infected host cells during a 3-min pulse with [35s]m ...1979422651
characterization of a sinbis virus variant with altered host range.a variant of sindbis virus which is much more infectious for mouse cells than the standard virus has been examined for biochemical properties which might be responsible for this biological difference. the variant has a much enhanced ability to adsorb to mouse plasmacytoma (mopc 315) cells, but when these cells were pretreated with heparin, they were able to adsorb the standard virus almost as well as the variant. this suggested that there was a surface charge difference between variant and stand ...1978708264
hexagonal glycoprotein arrays from sindbis virus membranes.freeze-etch electron microscopy of sindbis virus and of glycoprotein arrays derived from sindbis membranes by nonionic detergent treatment shows that the local geometry of glycoprotein-glycoprotein interaction does not depend on the presence of the nucleocapsid.1978722862
evidence for an autoprotease activity of sindbis virus capsid protein. 1978726255
virazole prevents production of sindbis virus and virus-induced cytopathic effect in aedes albopictus cells. 1978741653
inhibition of sindbis virus replication in aedes albopictus cells deprived of methionine. 1978741661
arthropod-borne virus infections in western new guinea (irian jaya): a serological retrospection.a serological investigation, covering many localities throughout western new guinea (irian jaya) in 1958-1961 showed that: a general endemicity of arbovirus infections rather than sporadic epidemics, exists in the southern lowlands--large differences exist in geographical distribution of these viruses especially when comparing coastal areas of the southern, with those of the northern and north western parts of the island--in both arbovirus groups noticeable differences in altitude were observed ...1978749276
[various properties of continuous culture of mosquito cells].the possibility of cultivating a continuous line of aedes aegypti mosquito cells in mitsuhashi and maramorosh medium and medium c-45 was studied. the results of morphological, karyological, and electron microscopic studies of these cells as well as the results of the study of isoenzymes of a. aegypti mosquito cells are presented. replication of sindbis, okhotsky, and baku viruses in these cells was demonstrated.1978749343
study on the mechanism of interference between friend leukemia and sindbis viruses in tissue culture.some mechanisms of interference developing in balb/c mouse embryo fibroblast culture (mec) infected with friend leukemia virus (flv) and 48 hours later superinfected with sindbis virus (sv) was studied. in flv-infected cells the amount of sv antigen formed was 2-3 times lower than in sv monoinfection, as indicated by immunofluorescence and cytofluorimetry. electron microscopic examination showed that in mixed infection the number of newly formed sv particles decreased markedly (by 90%) despite t ...1976775350
[clinical and epidemiologic significance of arboviruses in central europe]. 1976794666
[a rapid assay of sindbis virus infectivity by counting immunofluorescence foci in "aedes albopictus" cell culture (author's transl)].the aedes albopictus cell line is susceptible to numerous arboviruses but the appearance of cytopathic effect is observed mostly with flavivirus. a method of rapid titration of sindbis virus by counting immunofluorescent foci is described, using this cell line.1976799476
isolation of chikungunya virus contaminating an aedes albopictus cell line.an aedes albopictus cell line was found contaminated with structures morphologically compatible with an alphavirus. rapid isolation of a cytopathic virus was effected by combining sonication, concentration with aquacide ii-r, rate zonal sedimentation and subsequent plating of fractions on vero cells under agar overlay. the virus caused neithedeath nor disease on inoculation into infant and adult mice. it produced a c.p.e. in vero and bhk 21 cells, and multiplied in singh's aedes aegypti cells. t ...1975806659
immune lysis of sindbis virus. 1975808033
carbohydrate structure of sindbis virus glycoprotein e2 from virus grown in hamster and chicken cells.sindbis virus was used as a probe to examine glycosylation processes in two different species of cultured cells. parallel studies were carried out analyzing the carbohydrate added to sindbis glycoprotein e2 when the virus was grown in chicken embryo cells and bhk cells. the pronase glycopeptides of sindbis glycoprotein e2 were purified by a combination of ion-exchange and gel filtration chromatography. four glycopeptides were resolved, ranging in molecular weight from 1,800 to 2,700. structures ...1979430605
[the length of polyadenylic acid tracts of sindbis virus rna: the possible existence of two synthetic mechanisms].the poly (a) tracts of rna's from viral particles and from replicative complex belong to two classes of 180 and of 60 nucleotides in length. those of the mrna are homogenous and around 280 nucleotides in length. the results presented here strongly suggest the possibility of a copying mechanism in the first case and of a posttranscriptional addition in the latter.1975809185
ribosome-protected fragments from sindbis 42-s and 26-s rnas.sindbis virus 42-s and 26-s rnas labeled with 32p were purified from infected chick embryo fibroblasts. the rna's were incubated in the presence of a wheat germ cell-free translating system under conditions that yielded 40-s and 80-s initiation complexes. after digestion with rnase a, ribosome-protected fragments were isolated by polyacrylamide gel electrophoresis and compared with respect to number, size, cap content and oligonucleotide composition. the two rna species yielded several fragments ...1979436845
[comparative studies of two alphavirus by macroplaque assays and by a fluorescent focus method in vero cell lines (author's transl)].immune anti-sindbis and anti-chikungunya ascitic fluids have been titrated by the classic way of plaque reduction and by a quick fluorescent focus method using an indirect staining. the results are comparable, allowing to consider the use of this quick and inexpensive technic for counting-assays by neutralization.1976828464
purification and amino acid compositions of the structural proteins of sindbis virus. 1979473598
requirements for the insertion of the sindbis envelope glycoproteins into the endoplasmic reticulum membrane.previous work has shown that the sindbis structural proteins, core, the internal protein, and pe2 and e1, the integral membrane glycoproteins are synthesized as a polyprotein from a 26s mrna; core pe2 and e1 are derived by proteolytic cleavage of a nascent chain. newly synthesized core protein remains on the cytoplasmic side of the endoplasmic reticulum while newly synthesized pe2 and e1 are inserted into the lipid bilayer, presumably via their amino-termini. pe2 and e1 are glycosylated as nasce ...1979479287
a radioisotopic technique for measuring the mononuclear inflammatory response in sindbis virus-induced encephalitis of mice.the mononuclear inflammation occurring in sindbis virus-induced encephalitis of mice has been measured by means of pulse labelling with [125i]udr at a defined time after infection. the method should be applicable to other studies of encephalitis and of mononuclear cellular infiltration occurring in other organs as a result of disease or infection.1979479615
proteins specified by togaviruses in infected aedes albopictus (singh) mosquito cells.yields of greater than 10(7) p.f.u./ml at 28 or 37 degrees c of the alphavirus sindbis and the flavivirus kunjin were obtained in the aedes albopictus (singh) cell line, the latent periods being 4 to 6 and 10 to 12 h, respectively. despite a high background of host protein synthesis, virtually all the virus-specified proteins of the flaviviruses kunjin, dengue-2 and japanese encephalitis were labelled and resolved by slab gel electrophoresis of infected and uninfected cell proteins. in contrast, ...1979479844
biophysical studies on circle formation by sindbis virus 49 s rna. 1979513134
defective interfering particles of sindbis virus. iv. virion rna species and molecular weight determination of defective double-stranded rna. 1977841856
defective interfering particles of sindbis virus. v. sequence relationships between svstd 42 s rna and intracellular defective viral rnas. 1977841857
replication of standard and defective ross river virus in bhk cells: patterns of viral rna and polypeptide synthesis.virus-specific macromolecule synthesis has been examined in bhk cells infected with ross river virus. unpassaged virus (r-0) and tenth-passage virus (r-10) have been compared. in infected cells r-0 generates i) 45s, 28s, 33s and 26s viral rnas, ii) virus-specific precursor polypeptides of mol. wt. 127,000, 95,000 and 61,000 and iii) viral envelope proteins (mol. wts. 52,000 and 49,000) and nucleocapsid protein (mol. wt. 32,000). thus in terms of virus-specific rna and polypeptide synthesis, the ...1979518301
evidence for the synthesis of defection interfering particles by aedes albopictus cells persistently infected with sindbis virus. 1977855191
a study of neucleotide sequence homology between the nucleic acids of different alphaviruses. 1977860395
infectious virus-antibody complexes of sindbis virus.infectious virus-antibody complexes were formed when sindbis virus was reacted with antibodies raised against purified viral envelope glycoproteins e1 and e2 as well as against preparations of intact virus. results from rate zonal centrifugation in sucrose gradients of the complex formed with anti-e1 sera showed this complex to be about the same size as virions. a test of virus neutralization, based on direct plaque assay, by antibodies raised in rabbits and mice given virus in complete freund a ...1977870428
sindbis virus rna replication. i. properties of the 38s rna species.four species of single-stranded virus rna (49s, 38s, 33s and 26s) were detected in chick embryo fibroblasts infected with sindbis virus. the relative amounts of these rnas were unaffected by the m.o.i. there was also no significant difference in the molar proportions of the four rna species when purified virion rna was used as the inoculum. these findings suggest that the 38s and 33s species represent products of the transcription of non-defective virion rnas. kinetic analyses of rna synthesis i ...1979528982
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