PMID(sorted descending)
[clinical and epidemiologic significance of arboviruses in central europe]. 1976794666
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
[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
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
inhibition of sindbis virus replication in aedes albopictus cells deprived of methionine. 1978741661
virazole prevents production of sindbis virus and virus-induced cytopathic effect in aedes albopictus cells. 1978741653
evidence for an autoprotease activity of sindbis virus capsid protein. 1978726255
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
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
the effect of complement depletion on the course of sindbis virus infection in mice.the course of sindbis virus infection in 12-day-old balb/c mice was altered significantly in animals depleted of the third component of complement (c3) by treatment with purified cobra venom factor (covf). although the same percentage of c3-depleted and normal animals died (30%) after the subcutaneous inoculation of 1000 pfu sindbis virus, the mean day of death was later in c3-depleted mice (8.4 days) than in controls (6.5 days). in addition, morbidity was prolonged in c3-depleted mice. growth o ...1978701795
local resistance of chicken respiratory tract to viral infections. 1978696080
[arbovirus multiplication is mosquito cells treated with an interferon inducer]. 1978695524
effect of ouabain on sindbis virus replication in ouabain-sensitive and ouabain-resistant aedes albopictus cells (singh). 1978664253
replication of sindbis virus. vi. poly(a) and poly(u) in virus-specific rna species. 1978664244
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
altered e2 glycoprotein of sindbis virus and its use in complementation studies.we have detected a sindbis virus variant that contains a smaller-molecular-weight form of the viral glycoprotein e2. the molecular weight of the pe2 precursor and the glycosylation pattern of the smaller e2 are normal, thus indicating that this e2 is formed by an aberrant proteolytic cleavage. the altered e2 was detected in an rna+ temperature-sensitive mutant that was defective in proteolytic cleavage, but the abnormal pe2-to-e2 reaction could be separated from the ts mutation and is not itself ...1978650737
[persistence of sindbis virus in cultures either non-producing or irregularly producing oncornavirus].persistence of sindbis virus (sv) was studied for 9 months in two lines of mouse cell cultures (balb/c) in one of which the genome of endogenous ecotropic oncornaviruses was repressed. the other lines was exogenously infected at the level of plimary culture with rauscher leukemia virus (rlv) and sv and showed gradual inhibition of oncornavirus functions. the presence of oncornavirus type c was not the necessary condition for the development of persistent sv infection, however it influenced the c ...1978645057
effect of low-nacl medium on the envelope glycoproteins of sindbis virus.lowering the nacl concentration of the medium inhibits the release of sindbis virus from infected chicks cells at a stage after the nucleocapsids have bound to the membranes of the infected cells. the failure of trypsin treatment to release the inhibited virus and the ratio of the proteins in the inhibited cells make it seem likely that the inhibited virus is all intracellular. experiments using antisera specific for e1 and e2, the envelope glycoproteins of sindbis, suggest that the inhibitory e ...1978642072
regulation of the synthesis of sindbis virus-specified rna: role of the virion core protein.cells infected with seven different rna+ mutants of sindbis virus were found to accumulate a virus-specified polypeptide of mol. wt. 144000 (p144) during incubation at the non-permissive temperature, while at the same time synthesis of the virus structural proteins was drastically reduced. mapping of the tryptic peptides of p144 showed that it contained the amino acid sequences of all the virus structural proteins. at the non-permissive temperature cells infected with the same seven mutants (out ...1978632811
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
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
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
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
comparison of the carbohydrate of sinbis virus glycoproteins with the carbohydrate of host glycoproteins.the carbohydrate portions of the sindbis virus glycoproteins were compared with the carbohydrate portions of cell surface glycoproteins from uninfected host cells. comparisons of the size of glycopeptides were made using gel filtrations. comparisons of sugar linkages were made by methylation analysis. the conclusion was that the sindbis carbohydrate is similar to a portion of the host carbohydrate. thus, the sindbis carbohydrate structures appear to be structures normally made in the uninfected ...1977616485
arboviruses: persistence and defectiveness in sindbis virus infections. 1977600205
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
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
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
biological activity of hepatitis b antigens in cell interference by purified hepatitis b surface antigen or virus particles was not demonstrated in tissue culture. significant levels of interferon were not induced. the surface antigen did not block the adsorption of other viruses.1978569686
mutants of sindbis virus. iii. host polypeptides present in purified hr and ts103 virus particles.the amounts of host-encoded protein present in purified sindbis virions of both the hr strain and of a mutant (ts103) which makes multicored particles were examined. cells were labeled with [35s]methionine before infection and with [3h]methionine postinfection. virions were purified by velocity sedimentation and isopycnic banding, and their polypeptides were examined by polyacrylamide gels in a sodium dodecyl sulfate-containing discontinuous buffer system. host prelabeled material was found prin ...1978569218
replication of sindbis virus. vii. location of 5-methyl cytidine residues in virus-specific rna. 1978568849
effects of neuraminidase of the phenotype of sindbis virus grown in fibroblasts obtained from patients with i-cell disease. 1978568847
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
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
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
immediate glycosylation of 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 two viral glycoproteins are glycosylated before release from the polysome, and that this glycosylation involves transfer of a large 1800 dalton oligosaccharide to the polypeptide chains. the donor of the oligosaccharide is most probably a lipid.1977558830
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
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
[origin and formation of different types of vacuoles induced by the multiplication of the alphavirus sindbis virus in various cell systems].spherule-containing vacuoles and nucleocapsid-bearing vacuoles (cytopathic vacuoles types 1 and 2 respectively of grimley et al. 1968) induced by alphavirus sindbis were studied in brains from newborn mice, chicken embryo fibroblasts, and two lines of tumoral glial cells from muridae. endoplasmic reticulum (er) elements and finely granular electron-dense material also seen in contact with nucleocapsids seemed to be involved in the formation of the classical single-membrane spherule-containing va ...1979534962
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
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
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
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
biophysical studies on circle formation by sindbis virus 49 s rna. 1979513134
[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
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
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
the effect of membrane-active agents on sindbis virus 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
differential effects of ouabain on host- and sindbis virus-specified protein synthesis. 1979494493
the extreme 5'-terminal sequences of sindbis virus 26 and 42 s rna. 1979483569
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
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
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
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
purification and amino acid compositions of the structural proteins of sindbis virus. 1979473598
the pathogenesis of sindbis virus infection in athymic nude mice. 1979469246
[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
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
na+ and k+ concentrations and the regulation of protein synthesis in sindbis virus-infected chick cells. 1979462804
studies on the morphology of alphaviruses. 1979462801
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
comparison of sindbis virus and immunoglobulin glycopeptides in mouse myeloma cells. 1979447657
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
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
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
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
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
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
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
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
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
[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
[antiviral immunity in insects]. 1977332038
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
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
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
in vitro heterologous cytotoxicity by t effector cells from mice immunized with sindbis 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
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
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
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
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
purification of togavirus haemagglutinins by chromatography on controlled pore glass.purified preparations of haemagglutinins from sindbis, west nile and tick-borne encephalitis (tbe) viruses could be obtained from infected mouse brains by alkaline extraction, precipitation with protamine and chromatography on polyethylene glycol-coated controlled pore glass with 242 a pore diameter.1975241241
virus neutralizing antibodies to arboviruses in birds of the order anseriformes in czechoslovakia.sera from birds of the order anseriformes in czechoslovakia were examined for virus neutralizing (vn) antibodies to arboviruses. vn antibodies to sindbis, calovo and tahyna viruses were found in 15, 5 and 6 out of 106 greylag goose (anser anser) sera. out of 38 ducks, 6 mallards (anas platyrhynchos) and 1 garganey (anas querquedula) contained vn antibodies to sindbis virus, 6 mallards to calovo virus, 4 mallards and 1 garganey to tahyna virus, 2 mallards and 1 garganey to tick-borne encephalitis ...1975241234
streptovirudins -- new antibiotics with antiviral activity. the antiviral spectrum and inhibition of newcastle disease virus in cell cultures.streptovirudins are new antibiotics isolated as a mixture of several structurally related compounds from fermentations of streptomyces griseoflavus (krainsky) waksman et henrici var. thuringensis ja 10124. they possess antiviral activity against rna and dna viruses cultivated in chick embryo cells, namely sindbis, fowl plague, newcastle disease (ndv), pseudorabies, vaccinia and sheep abortion viruses. the naturally formed streptovirudin complex, in concentrations of 20-2.5 mug/ml inhibited the v ...1975241229
isolation and identification of group b arboviruses from the blood of birds captured in czechoslovakia.three west nile (wn) virus strains were isolated from the blood of birds (tringa ochropus, vanellus vanellus and streptopenia turtur) captured in south slovakia. one strain of tick-borne encephalitis (te) virus was isolated from the blood of tringa ochropus captured in south moravia.1975239564
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
arbovirus infections in sarawak, october 1968--february 1970 tembusu and sindbis virus isolations from mosquitoes.thirty isolations of tembusu virus and four of sindbis virus were obtained from approximately 280 000 mosquitoes collected between october 1968 and february 1970 in sarawak, particularly from k. tijirak, a land dyak village 19 miles south of kuching. twenty-two isolations of tembusu virus and two of sindbis virus were from culex tritaeniorhynchus; two of tembusu virus and two of sindbis virus came from culex gelidus. tembusu virus was active throughout the year at k. tijirak, the highest infecti ...1975235907
comparison of the sensitivity to ultraviolet irradiation of reovirus 3 and some viruses of the kemerovo group.the kinetics of uv inactivation of the tick-borne kemerovo (strain r-10) and lipovnik (strain lip-91) viruses which have been preliminarily classified as possible members of the reovirus group was examined. reovirus 3 and sindbis virus served as reference double-stranded rna and single-stranded rna viruses, respectively. the parameters of uv inresembled those of reovirus 3. this is consistent with their tentative classification as reovirus-like viruses.1975235204
ribonuclease-resistant rna of kemerovo virus.rna of partially purified kemerovo virus sedimented in a relatively broad region in sucrose density gradient with a peak at 14 s. approximately 65% of this rna was resistant to the action of ribonuclease which indicates the double-stranded nature of kemerovo virus rna.1975235200
interaction of sindbis virus with liposomal model membranes.radiolabeled sindbis virus was found to bind to protein-free lipid model membranes (liposomes) derived from extracts of sheep erythrocytes. the virus interaction was dependent on initial ph, and the range of ph dependence (ph 6.0 to 6.8) was the same as the observed with virus-dependent hemagglutination. after the initial interaction, ph changes no longer influenced the virus binding to liposomes. virus bound to liposomes prepared from a mixture of erythrocyte phospholipids, but the binding was ...1975234538
[inhibition of vaccinia, sindbis and para-influenza virus replication by isatin beta-thiosemicarbazone derivative and methisazone in vitro and in vivo]. 1979232050
the effect of interferon induction on complement level in rat.relatively high levels of interferon were achieved in rat sera by intracardial inoculation with sindbis virus followed 15 min later by intraperitoneal application of dimethylsulfoxide. at intervals when interferon titres reached the maximum, the levels of complement were decreased as compared with the control group of rats. single administration of dimethylsulfoxide did neither induce interferon nor influence the complement levels in sera of rats of the dobrá voda breed tested. similar results w ...1979230679
[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
glycopeptides of murine leukemia viruses. i. comparison of two ecotropic viruses.the glycopeptides obtained by pronase digestion of two ecotropic strains of murine leukemia virus (mulv) were compared by gel filtration. four different glycopeptide size classes, designated g(1), g(2), g(3), and g(4), with molecular weights of approximately 5,100, 2,900, 2,200, and 1,500, respectively, were shown to be associated with rauscher mulv virions grown in jls-v9 cells. various sugar precursors, including glucosamine, galactose, fucose, and mannose were incorporated into g(1) and g(2), ...1979228050
dimethyl sulfoxide enhancement of phlebotomus fever virus plaque formation.dimethyl sulfoxide (dmso)incorporated into an agar overlay containing deae-dextran enhanced plaque formation in vero cells by naples sandfly fever virus passaged in mouse brain or vero cell cultures. no plaques were visible when dmso was used without the deae-dextran, some plaques were rarely visible (less than 0.5mm) when deae-dextran was used without the dmso, and up to 10-fold more plaques were clearly visible (0.5-1.5 mm) when both chemicals were used. the combined enhancing effect of dmso a ...1979223461
assay of human interferon in vero cells by several methods.four methods for the assay of human interferon in vero cells were compared based on the inhibition of viral cytopathic effect (cpe) in tubes, the inhibition of cpe in microplates, the reduction of plaques, and the inhibition of quantitative hemadsorption. for inhibition of cpe, sindbis virus, vesicular stomatitis virus, poliovirus type 2, and vaccinia virus were used for challenge. in the plaque reduction method, sindbis virus, vesicular stomatitis virus, and poliovirus were employed, and newcas ...1979222803
antiviral action of benzo[de]isoquinoline-1,3-diones: 5-nitro-2-(2-dimethylaminoethyl) and 5-nitro-2-[2-(1-pyrrolidine)-ethyl] derivatives.two benzo[de]isoquinoline-diones, namely 5-nitro-2-(2-dimethylaminoethyl)-benzo[de]isoquinoline-1,3-dione and 5-nitro-2-[2-(1-pyrrolidine)-ethyl]-benzo[de]isoquinoline-1,3-dione, caused inhibition of the viral replication, when assayed against herpes simplex and vaccinia viruses in chick embryo cell cultures. influenza and sindbis virus replication were unaffected by these chemicals. virucidal effects were unobserved. the inhibitory activity is time-related. ocular and dermal infections with vac ...1979221156
[antiviral activity of interferon and its inducers in human lymphoblastoid and somatic cells].the antiviral effect of interferon inductors, such as poly-i--poly-c, phage f2 rna replicative form and low molecular inductor gsn and their influence on cellular dna synthesis were studied in the cultures of lymphoblastoid (inplanting lines raji namalva) and somatic human cells. the semliki forest virus used as the test organism multiplicated well in cells raji accumulating up to 9 lg bou/ml. the two-strand rna was less active in the lymphoid cells than in the somatic ones. gsn was 10 times mor ...1979220908
synthesis and processing of protein-linked oligosaccharides in vivo. 1979220252
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
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