PMID(sorted ascending)
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 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
the influence of arboviral infection on the susceptibility of cultured cells to immune injury in vitro.the susceptibility of llc-mk2 monkey kidney cells to antivirus (antibodies versus viral antigens in the plasma membrane) and anticell (antibodies versus plasma membrane antigens) immune cytolysis in vitro was observed during the course of 100 continuous subcultures of these cells. in that period, llc-mk2 cells infected with the group b arboviruses, japanese encephalitis virus and dengue 2 virus, became progressively refractory to the complement-dependent antivirus immune cytolysis as measured ...1975808137
[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
enveloped virus acquires membrane defect when passaged in fibroblasts from i-cell disease patients.sindbis virus obtained after passage on human fibroblasts from patients with i-cell disease (mucolipidosis ii) and called i-cell virus differed from sindbis virus obtained from chick fibroblasts or from normal human fibroblasts in two ways: (1) the i-cell virus was extremely unstable to freezing and thawing, (2) the i-cell virus showed greatly exaggerated sensitivity to inactivation by triton x-100. sindbis virus from fibroblasts from two patients with mucolipidosis iii, a milder form of i-cell ...1976821054
[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
[adaptation of a sindbis virus population to "drosophila melanogaster" (author's transl)].the evolution of a sindbis virus population during serial passages in drosophila has been studied. the adaptation of sindbis virus to this unusual host was achieved within about twenty passages. of course, the viral population went on evolving: a thermosensitive mutant appeared which excluded the original virus; later, a new type, different in plaques morphology, was observed: it did not exclude the former type but remained balanced with it. the adaptation of sindbis virus to drosophila was reve ...1976828837
free and membrane-bound polyribosomes in bhk cells infected with sindbis virus.the data presented in the paper demonstrate that in bhk cells infected with sindbis virus virtually all the 42s mrna not in nucleocapsid is associated with free polyribosomes, whereas the 26s mrna is distributed between free and membrane-bound polyribosomes. we suggest that the 26s rna polyribosomes are bound to the membranes through the nascent chains of the b1 protein and that a large percentage of 26s rna polyribosomes free in the cytoplasm may be due to the small amount of rough endoplasmic ...1977833938
interaction of sindbis virus glycoproteins during cells infected with the sindbis temperature-sensitive mutants ts-23 and ts-10 (complementation group d), which contain a defect in the envelope glycoprotein e1, the precursor polypeptide pe2 is not cleaved to the envelope glycoprotein e2 at the nonpermissive temperature. this defect is phenotypically identical to the defect observed in the complementation group e mutant, ts-20. the lesion in ts-23 is reversible upon shift to permissive temperature, whereas that of ts-10 is not. antiserum agai ...1977833949
how a single sindbis virus mrna directs the synthesis of one soluble protein and two integral membrane glycoproteins.previous work has shown that the 26s rna found in sindbis-infected chicken embryo fibroblasts encodes the three viral structural proteins, one internal protein, core, and two membrane glycoproteins, e1 and e2. this mrna has one initiation site; core, e1, and e2 are derived by proteolytic cleavage. here we show that during infection, the 26s rna is found mainly in membrane-bound polysomes which synthesize all three virion structural proteins. these polysomes are released from the membrane upon tr ...1977837448
effects of udp-glucose addition on the synthesis of mannosyl lipid-linked oligosaccharides by cell-free fibroblast preparations.the pattern of mannosyl lipid-linked oligosaccharides synthesized by cell-free enzyme preparations from cultured fibroblasts is altered substantially when 0.2 mum udp-glucose is added to the incubation medium. inclusion of udp-glucose results in the appearance of a new labeled oligosaccharide, which is 1 or 2 glycose units larger than the lipid-linked oligosaccharide synthesized in the presence of only gdp-mannose (2 mum) and udp-n-acetylglucosamine (20 mum). label from udp-[3h]glucose is incorp ...1977838742
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
role of the immune response in recovery from sindbis virus encephalitis in mice.the role of the immune response in recovery from acute encephalitis was studied by using a neuroadapted strain of sindbis virus. intracerebral inoculation of this virus caused fatal disease in weanling mice. passive transfer of homologous immune serum protected mice, but transfer of immune spleen cells and lymph node cells failed to alter mortality. transfers were made 24 hr after intracerebral infection of the recipient, when central nervous system infection was established. the protective fact ...1977845432
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
envelopments of sindbis virus: synthesis and organization of proteins in cells infected with wild type and maturation-defective mutants.the synthesis and organization of sindbis virus structural proteins was investigated in bhk cells infected with wild-type virus (svhr) or temperature-sensitive (ts) mutants defective in maturation. cells infected with ts-23 or ts-20 (complementation groups d and e) were similar in the polypeptides synthesized at the nonpermissive temperature and differed from svhr-infected cells in that the envelope protein e2 was not cleaved from the pe2 precursor. data from experiments utilizing pulse-chase pr ...1977875134
rat interferons. iv. sialoproteins in rat serum.introduction of virus as inductor of interferon into rats caused a decline in serum levels of sialic acid in blood taken at the time of maximum interferon activity. differences in the acute phase proteins were dependent on the type of virus used for induction. ndv injected intravenously did not lower serum levels of seromucoid, but given together with dmso markedly depressed the content of this protein in the serum. stimulation of interferon production by sindbis virus was accompanied by a signi ...1977879992
strategy of the flavivirus genome: evidence for multiple internal initiation of translation of proteins specified by kunjin virus in mammalian cells. 1977888349
[cellular immune lysis patterns in viral infection]. 1977888574
a comparison of saint louis encephalitis and sindbis virus rna.rna isolated from purified st. louis encephalitis and sindbis virus particles was compared by cellulose cf-11 chromatography, and rnase t1 and pancreatic rnase a digestion. sle rna eluted from the cellulose cf-11 column as a molecule with very little secondary structure, while sindbis appears to have some internal bonding. ribonuclease digestion indicates that sle rna contains 2.4 per cent polyadenylic acid.1977889439
pathogenesis of temperature-sensitive mutants of sindbis virus in the embryonated egg. iii. autologous, homologous, and heterologous interference.two temperature-sensitive (ts) mutants of sindbis virus able to synthetize rna, but not two ts mutants defective in viral rna synthesis, reduced to lethality of the superinfecting heat-resistant parent strain of sindbis virus in embryonated chicken eggs as compared with results in controls. autologous interference (of mutant with parent) was observed under a variety of conditions. time-course studies in one selected system showed that lower titers of superinfecting parent virus were detected in ...1977889615
antibody-dependent, complement-mediated homologous and cross-cytolysis of togavirus-infected cells.the appearance of viral induced antigen(s) on sindbis and semliki forest (sf) virus-infected chick embryo cells is detected with homologous mouse anti-viral antibody-dependent, complement-mediated cytolysis in a 51cr release assay. such antigen(s) is detected within 3 to 4 hr after infection whereas viral cytopathologic effects do not occur until 10 to 12 hr. in addition, significant heterologous cytolysis (anti-sindbis on sf virus-infected cells, or, anti-sfv on sindbis-infected cells) could be ...1977894036
the mechanism of the inactivation of human fibroblast interferon by mechanical stress.interferon derived from human fibroblasts is readily inactivated during agitation and filtration. this inactivation has been shown to be largely a product of mechanical stress, and has been studied in detail by subjecting interferon to controlled shear stress using a rotational viscometer. the possible mechanism of this phenomenon is discussed.1977894266
the continued presence of interferon is not required for activation of cells by interferon. 1977896806
mutants of sindbis virus. ii. characterization of a maturation-defective mutant, ts103. 1977898673
evolution and properties of aedes albopictus cell cultures persistently infected with sindbis virus. 1977898680
nucleolar fragmentation in cells infected with alphaviruses (39886). 1977909877
the significance and nature of defective interfering viruses.deletions in viral genomes appear to be a common occurrence in the replication of all dna and rna viruses which have been adequately studied. such defective genomes can replicate in the presence in the same cell of a helper virus as long as the deletion does not involve the initiation site for genome replication. coinfection of a cell with defective and "normal" infectious virus leads to reduction in the yield of the latter. the nature of di viruses and genomes found in sindbis virus-infected ve ...1977912148
reaction of the protease inhibitor p-nitrophenyl-p'-guanidinobenzoate with sindbis virus. 1977929977
karyotype alterations of bhk-21 cell lines by persistent virus infections i. development of the cell lines and conventional chromosome analysis.from bhk-21 cell cultures inoculated with different viruses cell lines with persistent infection were developed and examined for alterations in their karyotypes. in all cell lines studied, even in those no longer producing infective virus chromosomal breaks and interchanges were observed. besides these effects probably induced directly by the virus infection, a shift in the number of chromosomes was found. based on certain properties of the bhk-21 cell lines carrying a virus infection a hypothes ...1977930469
rat interferons. homologous and heterologus rat serum activity.serum proteins from normal rat serum and induced with sindbis virus were separated on sephadex g-100. interferon activity was studied in a system of homologous rec and heterologous lg cells. proteins of normal serum as well as induced serum emerged in two peaks separated by a deep saddle. four hours after induction, the serum gave two peaks with similar interferon activity in both cell systems. after 8-hour induction, two interferons were also obtained, but activity in the heterologous system wa ...1977931553
variants of the hr strain of sindbis virus lethal for mice.we have selected two similar variants of sindbis hr virus which are lethal for mice. consecutive brain to brain passage series were conducted in suckling and weanling mice. specific anti-sindbis hr neutralization tests and protection tests demonstrate that these viruses are derived from the parent sindbis hr.1976932692
the effect of infection with sindbis virus and its temperature-sensitive mutants on cellular protein and dna synthesis. 1976936476
polyadenylic acid size and position found in sindbis virus genome and mrna species. 1976936483
sialic acid contents of sindbis virus from vertebrate and mosquito cells. equivalence of biological and immunological viral properties. 1976942807
[infection of mice with sindbis virus during pregnancy]. 1976944402
inhibition of sindbis virus replication by zinc ions. 1976945640
the induction of interferon by temperature-sensitive mutants of sindbis virus: its relationship to double-stranded rna synthesis and cytopathic effect.sindbis virus strain ar339 induces interferon by 3 h after infection at 39 degrees c and by 8 h after infection at 30 degrees c. the time course of interferon induction between 4 and 9 h after infection at the restrictive temperature (39 degrees c) was measured for 24 temperature-sensitive (ts) mutants, all of which induced interferon by 16 h after infection. mutants showing total rna synthesis at 39 degrees c greater than 10% of the wild-type level induced interferon with kinetics similar to th ...1976950559
proposed nomenclature for alphavirus polypeptides. 1976950561
kinetics of the rapid action of interferon.the present study was undertaken to examine some factors which lead to early-appearing resistance in human cells treated with interferon. it was previously shown that two conditions required for rapid development of resistance were continuous maintenance of cultures at 37 degrees and use of more than 10 units/ml of interferon. the decay kinetics of the established resistance appear to be approximately the same whether the resistance was induced under conditions favoring rapid or slow development ...1976967891
defective interfering passages of sindbis virus: nature of the defective virion rna.defective interfering particles of sindbis virus contain 20s rna identical to that found in bhk cells co-infected with standard and defective virions. we have characterized these rnas by their oligonucleotide fingerprints. most of the oligonucleotides were identical to those found in the mrna (26s rna) that codes for the virion structural proteins. three oligonucleotides found in 20s rna were absent from the 26s rna pattern and may represent sequences from the 5' end of the virion rna. previous ...1976972428
defects in rna+ temperature-sensitive mutants of sindbis virus and evidence for a complex of pe2-e1 viral glycoproteins. 1976982835
microviscosity of togavirus membranes studied by fluorescence depolarization: influence of envelope proteins and the host cell.the microviscosities of the hydrophobic regions of the membranes of intact semliki forest and sindbis viruses grown on bhk-21 cells, of liposomes derived from the extracted viral lipids, and of protease-treated virions were measured by fluorescence depolorization using the fluorescence probe 1, 6-diphenyl-1,3,5-hexatriene. the intact virus membranes were found to have a higher microviscosity than did virus-derived liposomes, indicating the viral envelope proteins contribute to microviscosity. ho ...1976985887
failure of defective interfering particles of sindbis virus produced in bhk or chicken cells to affect viral replication in aedes albopictus cells.whereas defective interfering particles of sindbis virus are readily produced in bhk-21 cells or chicken embryo fibroblasts by the techniques of serial undiluted passage, similar methods failed to generate such particles in aedes albopictus cell cultures. in addition, sindbis virus stocks produced in bhk-21 cells or chicken embryo fibroblasts and which contained defective interfering particles, when tested in a. albopictus cells, failed (i) to interfere with the replication of standard sindbis v ...1976986481
characteristics of sindbis virus temperature-sensitive mutants in cultured bhk-21 and aedes albopictus (mosquito) cells.a number of the temperature-sensitive mutants of sindbis virus originally isolated and characterized by burge and pfefferkorn (1966, 1968) were reexamined for their abilities to grow and complement one another in cultured bhk-21 and aedes albopictus (mosquito) cells. the response of the mutants to conditions of high and low temperature was similar in cultured cells of both the vertebrate and invertebrate hosts. complementation experiments in bhk-21 cells produced growth patterns similar to those ...1976987251
asymmetry of the lipid-bilayer of sindbis virus.the organization of the lipid bilayer of the enveloped sindbis virus has been studied. in the model membrane which consists only of two virus specific glycoproteins and host derived lipids the latter were radioactively labelled with 14c-palmitic acid by prelabelling their bhk 21 host cell lipids. the purified virus particles were submitted to neuramidase, bromelain and combromelain-neuraminidase treatment. it could be demonstrated that n-acetyl neuraminic acid residue of the total hematoside pre ...1976991384
formation of a sindbis virus nonstructural protein and its relation of 42s mrna function.chicken embryo fibroblasts infected with an rna- temperature-sensitive mutant (ts24) of sindbis virus accumulated a large-molecular-weight protein (p200) when cells were shifted from the permissive to nonpermissive temperature. appearance of p200 was accompanied by a decrease in the synthesis of viral structural proteins, but [35s]methionine tryptic peptides from p200 were different from those derived from a 140,000-molecular-weight polypeptide that contains the amino acid sequences of viral str ...1976994299
purification and composition of the proteins from sindbis virus grown in chick and bhk cells.procedures are described for the purification of the sindbis virus structural proteins. the amino acid and carbohydrate compositions of the purified proteins are presented for virus grown in bhk-21/13 and chicken embryo cells. glycoprotein e1 from virus grown in bhk cells is deficient in a mannose-rich glycopeptide found on that glycoprotein when virus is grown in chicken embryo cells. the complex glactose-containing glycopeptides appear similar for virus grown in both hosts. however, when virus ...1976994303
di-and trimethylated congeners of 7-methylguanine in sindbis virus mrna. 1976995206
maintenance and recovery of the interferon-induced antiviral state. 1976995931
[polyuridylic sequences and negative strands of sindbis virus-specific rnas: study by affinity chromatography on poly (a)-sepharose columns (author's transl)].the experimental conditions of affinity chromatography on poly (a)-sepharose columns have been determined. this method makes obvious the existence of polyuridylic acid sequences on the negative strands of sinbis virus-spedific rnas. the isolated rnas are negative and positive strands hybrids. by polyacrylamide gel electrophoresis, it has been shown that the negative strands have the same length as the 26 s interjacent rna at the 6th hour, and as the 42 s virion rna at the 9th hour postinfection. ...1976999128
antibodies against arboviruses in sierra leone.sera from 180 blood donors in sierra leone were examined by combined hemagglutination - inhibition, complement fixation, and neutralization tests for antibodies against 10 arbovirus. the donors were 20 to 40 years old and resident at panguma, tongo, serabu and segbwema. thirty sera (16.6%) had antibodies to group b viruses, the majority of which were to yellow fever virus as confirmed by n tests. nineteen sera had antibodies to arumowot virus and 4 to sindbis virus. n antibodies against ugmp 359 ...19761006793
laboratory studies on the vector capability of aedes (neomelaniconion) unidentatus mcintosh and aedes (aedimorphus/ dentatus (theobald) with west nile and sindbis viruses.laboratory tests were made with aedes (neomelaniconion) unidentatus mcintosh and aedes (aedimorphus) dentatus (theobald) collected from the highveld region of the transvaal, south africa, to determine their ability of transmit west nile and sindbis viruses. viraemic hamsters or a viraemic chick were exposed to the mosquitoes as infective meals. infection of mosquitoes was determined by testing mosquitoes individually for the presence of virus 10-26 days later. transmission of virus, attempted be ...19761019752
ord river arboviruses--serological epidemiology.this paper presents the results of haemagglutination-inhibition tests carried out on sera from 441 persons, 1,080 cattle and 335 birds in the kimberley area. two alphaviruses (group a) (ross river and sindbis) and one flavivirus (murray valley encephalitis) were used for the preparation of haemagglutinins in the haemagglutination-inhibition tests. the tests showed a high percentage of antibody of murray valley encephalitis in humans, birds and cattle, with an obvious focus of infection in the st ...19761021093
[identification of rnaase-sensitive 20s rna in a cell culture infected with sindbis virus].rnase-sensitive 20s rna component with molecular weight of 0.7-10(6) is found when analysing virus-specific rnas isolated from cultured chicken embryo fibroblasts infected with sindbis virus by means of gradient centrifugation and polyacrylamide gel electrophoresis.19761022269
[synthesis and the action of adamantane derivatives on the sindbis virus]. 19761026489
[effect of rimantadine on the synthesis of virus-specific rna in the culture of cells infected with sindbis virus].effect of rimanthadine (alpha-methyl-i-adamantane methylamine) on the synthesis of virus specific rna was studied in culture of cells, infected with syndbis virus. rimanthadine inhibits the synthesis of virus specific rna beginning from the 3-rd hr of infection. a magnitude of inhibition from the 3-rd to the 7-th hrs of infection was practically the same and exceeded 50%. in the presence of rimanthadine "early" rna was formed (with sedimentation constant of 20-14 s), where radioactivity was lowe ...19761027258
the production and action of interferon in chinese hamster cells.the interferon system has been investigated in primary cell cultures established from chinese hamster embryos and new born pups. interferon synthesis was induced with sindbis virus, ultraviolet inrradiated newcastle disease virus (u.v.-ndv) and with polyriboinosine acid-polyribocytidylic acid complex [poly (ri). poly (rc)]. only u.v.-ndv induced significant production of interferon, maximum amounts being produced in 'aged' cells. its apparent mol. wt. was 25000. cho-ki cells, an established line ...19761033270
uv irradiation of interferon-treated chick embryo cells enhances sindbis virus growth. 19761035095
[integration and transfection of an arbovirus by mammalian cells].a system: l cells chronically infected with sindbis virus was studied. unlike acute infection wherein the mature virions are produced, the chronically infected tissue culture produces subviral structures-infectious ribonucleoproteins. molecular hybridization experiments revealed the integration of the viral genome (dna-transcript) into the cellular genome. transfection experiments showed the possibility to induce the synthesis of the virus in sensitive cells treated with dna from the chronically ...19761053085
production of interferon in the white mouse by dimethyl sulfoxide. 19751055550
in vivo behavior of a sindbis virus mutant isolated from persistently infected aedes aegypti cell cultures.a mutant of the sindbis virus sv-s was found to interfere with the regular course of infection by the wild strain of the virus sv-w in a. aegypti mosquitoes and in suckling mice. in mosquitoes, this result was manifested by a reduced titer of sv-w in the presence of sv-s and by a failure of the mosquitoes to transmit sv-w. in the brains of suckling mice, in the presence of sv-s, the growth of sc inoculated sv-w was suppressed, and as a result, the usually lethal course of infection by this virus ...19751072594
observations of aedes albopictus cell cultures persistently infected with sindbis virus. 19751072595
neutralization of a togavirus by antivector a. aegypti-propagated togavirus (sindbis) is neutralized by antisera to both whole-body extracts and to salivary fluid of the vector mosquito. virus propagated in vero cells is not neutralized by such antisera. neutralizing activity resides in the immune globulin fraction of sera. sera from animals injected with adjuvant neutralized neither virus propagated in mosquitoes nor virus obtained from vero cells. although neutralizing titers were low, such activity may protect, to some degree, verte ...19751072597
preliminary evidence for cell-mediated immunity in cross-protection among group a arboviruses.unfractionated and t cell-enriched populations from spleens of mice immunized with sinbdis virus confer cross-protection against semliki forest virus challenge in recipient mice. both group a viruses are serologically related, but not by tests for cross-neutralizing antibody. the protection in mice persisted for three consecutive cell passages in uninfected mice. the results suggest that cell-mediated immunity accounts for cross-protection.19751079033
inhibition of group b arbovirus antigen production and replication in cells enucleated with cytochalasin b.a comparative study of the growth of sindbis (sin) virus, a group a arbovirus (togavirus), and japanese encephalitis (je) virus, a representative group b arbovirus (togavirus), was conducted in enucleate and nucleate cells. immunofluorescent tests and yield measurements demonstrated that chicken embryo cells which had been enucleated and subsequently infected with sin virus produced virus-specific antigens and infectious virus. by contrast, je failed to replicate or produce virus-specific antige ...19751090752
sindbis virus replication in vertebrate and mosquito cells: an interpretation.this paper summarizes recent comparative studies of sindbis virus (sv) replication in cultured aedes albopictus (a. albo) or (a. aegypti (a. aeg) and bhk21 or chick embryo (cef) cells. 1. viral growth kinetics and yields are similar in a. albo cells at 28 degress c and in vertebrate cells at 37 degrees c. a. albo exhibit no cpe and yield persistenetly infected cultures. 2. sv grown in a. albo cells lacks sialic acid but is antigenically and in terms of particle/pfu or particle/hau ratios equival ...19751107684
processing of alphavirus-specific proteins in infected cells.the rna of the alphaviruses contains the genetic information for both the non-structural and the structural polypeptides. the former are contained in the initial two-thirds of the sequence (from the 5'-terminus) and are read directly from the virus particle rna, but whether post-translational cleavage is involved or not is not known. the genes for the structural polypeptides are in the final one-third of the genome, and are probably not read directly but are transcribed selectively to produce a ...19751107686
[possible mechanisms of chronic viral infections (author's transl)]. 19751108450
[multiplication of sindbis virus in drosophila cells cultivated in vitro (author's transl)].sindbis virus replicates in drosophila cell cultures without any cytopathic effect. in continuous cell lines the virus is able to establish a persistent infection similar to other arboviruses in insect cell lines. the growth curve of sindbis virus in drosophila cells shows a maximum virus yield at around 24 hours postinfection, thereafter the virus production decreases and then remains fairly constant during a number of cell divisions. the average virus yield per cell has been estimated to be sm ...19751147779
changes of the cell type of bhk-21 lines by persistent sindbis virus.persistent infection by sindbis virus (sv) can be induced in cultures of bhk-21 cells. in a persistently infected cell line only 5% of the cells produced virus. virus titers in the medium reached 10(5) pfu per ml. a persistent infection could be eliminated from cultures by seeding at most 100 cells per bottle. compared with the original line decontaminated lines differed in several properties. after infection with sv ten times less virus was released into the medium, and an infection persisted w ...19751154915
neutralization of sindbis virus by antisera to antigens of vector mosquitoes.sindbis virus harvested from infected cultures of vero cells and from aedes aegypti mosquitoes was used in neutralization tests with sera obtained from guinea pigs immunized with ground a. aegypti and from guinea pigs repetitively bitten by mosquitoes. employing these antisera, more mosquito-propagated virus was neutralized than was virus grown in cultures of vero cells. the neutralizing activity resided in the immune globulin fraction and may reflect the production of antibody to vector antigen ...19751155692
the distribution and prevalence of group a arbovirus neutralizing antibodies among human populations in southeast asia and the pacific islands.plaque reduction neutralization tests, using five group a arboviruses (chikungunya, ross river, getah, bebaru and sindbis), were done on sera from human populations in 44 southeast asia and pacific island localities. specificity of the plaque neutralization test was determined by examining convalescent sera from patients with known alphavirus infections. chikungunya-specific neutralizing antibodies were demonstrated in sera of persons living in south vietnam, northern malaysia, indonesia (kalima ...19751155702
isolation of murray valley encephalitis virus from sentinel chickens.sentinel chickens were established in 3 centres along the murray valley on 20 december 1973. the demonstration of antibody in the serum of chickens in the mildura and kerang areas indicated sindbis virus activity late in december 1973 and early in january 1974. tests for antibody to mve virus were negative until blood collected from one chicken at echuca on 27 february 1974 and several chickens at mildura and kerang on 14 march 1974, showed positive hi reactions. murray valley encephalitis virus ...19751164265
interfering passages of sindbis virus: concomitant appearance of interference, morphological variants, and trucated viral rna.serial passage of sindbis at high multiplicities of infection resulted in cyclical variations in virus titer. decreases in virus titer were correlated with the appearance of smaller-sized virions, interference and truncated viral rna. the smaller particles were 37 nm in diameter, exclusive of the hemagglutinin spikes as compared with a diameter of 50 nm for standard virions. passages which contained 37-nm partilces also interfered with infectious center formation by standard, plaque-purified vir ...19751165599
alterations in sindbis viral enbelope proteins by treating bhk cells with glucosamine.addition of d-glucosamine to bhk cells infected with sindbis virus inhibited the formation of the e-2 viral envelope from its precursor pe-2. release of virus was blocked, and two new viral protein bands replaced the normal envelope protein bands detected in sds-gel electropherograms of infected cell extracts.19751167605
isolation of a sindbis virus variant by passage on mouse plasmacytoma cells.a variant of sindbis virus has been isolated by growing a stock of virus, previously passaged on chicken embryo cells, in mouse plasmacytoma (mopc 315) cells in suspension culture. an indirect immunofluorescence test and infective center assay showed that only a small fraction of cells could be infected by the stock wild-type virus, but that the population of virus accumulating after a few passages on the mouse cells had host-range properties distinct from the stock virus. the mouse-passaged vir ...19751167912
the role of interferon in interference and auto-interference elicited by newcastle disease virus.newcastle disease virus (ndv) strains interfere in different degree with the growth of the velogenic ndv strain texas gb (homologous interference) and sindbis virus (heterologous interference) in chick embryo fibroblast cells. homologous interference was elicited by interferon-producing live or uv-inactivated strains and non-interferon-producing live or beta-propiolactone-inactivated strains and it was not influenced by actinomycin d. thus, interferon had apparently no role in homologous interfe ...19751168397
replication of lactic dehydrogenase virus and sindbis virus in mouse peritoneal macrophages. induction of interferon and phenotypic mixing. 19751170684
structure and chemical-physical characteristics of lactate dehydrogenase-elevating virus and its rna.lactate dehydrogenase-elevating virus (ldv) was purified from culture fluid of infected primary cultures of various mouse tissues (peritoneal macrophage, bone marrow, spleen, and embryo) and from plasma of infected mice. electron microscopy of negatively stained virus and positively stained sections of ldv revealed spherical particles of uniform size with a diameter of about 55 nm, containing an electron-dense core with a diameter of about 30 nm. during sample preparation the envelope had a tend ...19751171266
sindbis virus glycoproteins: effect of the host cell on the oligosaccharides.sindbis virus was grown in four different host cells and the carbohydrate portions of the glycoproteins were analyzed. sindbis virus grown in bhk-21 cells has more sialic acid and galactose than sindbis virus grown in chicken embryo cells. in other respects the carbohydrates from virus grown in these two hosts are very similar. sindbis virus grown either in chick cells transformed by rous sarcoma virus or in bhk cells transformed by polyoma virus was also examined. in comparisons of virus from n ...19751171992
defective interfering particles of sindbis virus. iii. intracellular viral rna species in chick embryo cell cultures. 19751172323
initiation sites for translation of sindbis virus 42s and 26s messenger rnas.sindbis virus 26s rna is the principal species of virus-specific rna found in the infected cell; it is derived from a one third segment of virion 42s rna. when translated in cell-free extracts from mouse ascites cells or rabbit reticulocytes, 26s rna directed the synthesis primarily of the 33,000 dalton virus capsid protein, and the protein products were in the form of free peptides rather than peptidyl-trna. in contrast, the polypeptides synthesized in either extract in response to sindbis viru ...19751182802
crystalline arrays of nucleocapsids in sindbis virus-infected l cells. 19751184346
unexpectedly rapid action of human interferon in physiological conditions. 19751186843
methylation of sindbis virus "26s" messenger rna. 19751191298
defective particles in alphavirus infections.this article summarizes our studies with defective-interfering particles of sindbis virus obtained by high multiplicity passaging of the virus in bhk cells. cells infected with these defective passages accumulate a species of rna (20s) at the expense of 26s rna--the mrna coding for the viral structural proteins. although the structure of the rna in defective particles remains undefined, our studies of replicative forms and replicative intermediates suggest that it is larger than the intracellula ...19751207189
function of sindbis virus 49s and 26s rnas in in vitro protein synthesizing systems. a summary. 19751207190
sindbis virus infected l cells studied by ferritin-labelled antibodies.sindbis virus infected l cells were examined by immunoferritin technique at different times after infection. initially virus-specific antigens appeared diffusely distributed in the cytoplasm and at the surface of vacuoles. later on, both labelled nucleocapsids surrounding vacuoles and mature virus within their lumen were demonstrated. maturation of virus occurred predominantly at the periphery of cells, and that mainly by budding from cell processes. the appearance of big crystals consisting of ...19751221673
[study of the antiviral action of gentamicin].experimental data on the effect of various concentrations of gentamycin on reproduction of vee and sindbis viruses in tissue culture are presented. it was found that gentamycin had no cytotoxic effect on the primary tripsinized chick embryon fibroblasts (cef) when used in doses of 10, 20 or 30 mg/ml and only when used in a dose of 50 mg/ml it induced 50 percent destruction of the cell layer. multiplication of the vee and sindbis viruses in the culture of cef was inhibited in the presence of gent ...19751225192
requirement of cell nucleus for the replication of an hamster kidney (bhk21) cells enucleated with cytochalasin b were infected with pichinde virus or sindbis virus. viral replication was measured by plaque assay, and the synthesis of viral antigens was determined by immunofluorescence. pichinde virus replication was completely inhibited in cells enucleated prior to infection as measured by both techniques while the replication of sindbis virus was unaffected. enucleation of cells at different times after infection with pichinde virus indicate ...19751235853
interferon induction by viruses and polynucleotides: a differential effect of comptothecin.the plant alkaloid comptothecin inhibits interferon production induced by newcastle disease virus (ndv) or ultraviolet-irradiated ndv in chick and human cells, and by sindbis virus in chick cells. it has no effect on interferon production induced by poly (ri).poly(rc) in chick and human cells. no effect of comptothecin could be detected on the multiplication of ndv, and it is concluded that the inhibition reflects a difference between interferon induction by viruses and by polynucleotides.19751239490
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