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
the production of chinese hamster interferon. 197611678
reversible inhibition of interferon-induced antiviral state by deoxyadenosine.deoxyadenosine reversibly inhibited the development of antiviral state (avs) in chick embryo fibroblasts stimulated by interferon. studies on cellular macromolecular syntheses in deoxyadenosine-treated cells suggested that the inhibition was related to nucleolar rna synthesis. reference experiments with actinomycin d and cordycepin (3'deoxyadenosine) also implied causal- or interrelation between avs development and nucleolar rna synthesis.197613641
growth medium utilization and its re-use for animal cell cultures. 197714164
stability in drinking and surface water of nine virus species from different genera (author's transl).the stability of nine viruses, aujeszky, sindbis, vesicular stomatitis, newcastle disease, vaccinia, fmd, hcc, reo and teschen virus in drinking and surface water was investigated comparatively at temperatures of 9 and 15 degrees c as well as the influence of water factors like seasonal difference in temperature, ph value, hardness and sort of water. the results can be summarized as follows: 1. at temperatures of 9 to 15 degrees c the majority of the viruses remained stabil in natural water for ...197714460
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
effect of sindbis virus infection on hydrocortisone-induced hepatic enzymes in mice. 197823548
isolation of sindbis (alphavirus) and leanyer viruses from mosquitoes collected in the northern territory of australia, 1974.mosquitoes collected near darwin, northern territory, in 1974 yielded two virus strains. one was identified as sindbis virus, not previously isolated from the northern territory. the other is antigenically distinct from viruses previously isolated from arthropods in australia, and the name "leanyer" is proposed for it. its properties suggest that it may be a togavirus serologically unrelated to available alphaviruses and flaviviruses.197723749
isolation of sindbis virus from the frog rana ridibunda. 197825014
comparative studies on sindbis virus strains isolated in slovakia.two variants of sindbis virus strains were distinguished according to the dextran sulphate (ds) marker. large-plague strains freshly isolated from cricetus cricetus and rana ridibunda produced exclusively small plaques after ds treatment. the prototype sindbis virus strain produced both large and small plaques after ds treatment. kinetic haemagglutination-inhibition tests revealed a higher reactivity of freshly isolated strains than of the prototype strain. for differentiation of newly isolated ...197826202
identification of a sindbis virus strain isolated from hyaloma marginatum ticks in sicily. 197827971
interspecies interactions of arboviruses. iii. competition for virus envelope antigens in mixed getah and sindbis virus populations.interactions of getah and sindbis virus populations in mixed infections of 5 tissue systems were competitive or neutral. the type of interaction is regulated by the host cell and virus population density. on reproduction in mouse brains and spev cell cultures the mixed population exhibited antigenic markers of getah virus; in syrian hamster kidney and chick embryo cell cultures those of sindbis virus; and in chinese hamster kidney cell cultures the antigenic markers of both viruses. mixed popula ...197829465
detection of sindbis and west nile viruses in the blood of living birds by indirect haemagglutination. 197830270
novel antiviral activity found in the media of sindbis virus-persistently infected mosquito (aedes albopictus) cell cultures.aedes albopictus (mosquito) cells persistently infected with sindbis virus for a period of 6 months release into the medium a low-molecular-weight material capable of specifically reducing the yields of sindbis virus during the "acute phase" of infection in mosquito cells. the antiviral activity was produced in detectable levels at 3 days after infection, and its concentration in the extracellular medium increased thereafter. the antiviral activity was inactivated by treatment with the enzyme pr ...197934732
alphaviruses in peninusular malaysia: i. virus isolations and animal serology.a survey of the activity of three alphaviruses (sindbis, getah and chikungunya) in peninsular malaysia was conducted between 1962 and 1970. serum samples were examined from 3,917 vertebrates representing a wide variety of wild and domestic animals throughout the peninsula for hemagglutination-inhibiting and neutralizing antibodies. a total of 548,939 mosquitoes were collected from different habitats, including jungle, rural, suburban and urban areas, and the majority of the females taken were ex ...197834888
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
the effect of ribonuclease on the replicative forms of sindbis virus rna.three species of double-stranded rna, designated rf i, rf ii, and rf iii in order of decreasing size (25), are produced by ribonuclease treatment of extracts of chicken embryo cells infected for 6 hours with sindbis virus. only one class of replicative form rna is present in extracts not treated with ribonuclease; this class contains some molecules which can be enzymatically cleaved to produce the other two replicative forms. at a low level of enzyme (0.001 microgram/ml) the major species obtain ...197939537
quantitative and rapid assays of togaviruses by immunofluorescence.for the quantitative assay of selected togaviruses, suspensions of bhk cells were inoculated with virus and grown in spinner cultures. at intervals, dependent on the growth characteristics of the viruses, about 10(3) cells were centrifuged on to microscope slides and then stained with fluorescent antibody. for rapid demonstration (2--3 hr) of specific viral antigens, virus was bound in successive dilutions onto microscope slides and stained. binding of specific anti-virus antibodies in both meth ...197940420
biological properties of three spontaneous mutants of sindbis virus. 197546745
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
sindbis virus glycoproteins form a regular icosahedral surface lattice.electron micrographs of negatively stained sindbis virus particles show that the glycoproteins are organized with trimer clustering in a t = 4 icosahedral surface lattice.197548559
the specificity and applications of antibodies to helical nucleic acids. 197550162
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
antigenic characterization of two sindbis envelope glycoproteins separated by isoelectric focusing. 197654983
mutants of sindbis virus. i. isolation and partial characterization of 89 new temperature-sensitive mutants. 197662444
[persistence of the sindbis virus in cultures producing oncornavirus].continuous lines were obtained from primary cultures of balb/c mouse embryo cells which were found by electron microscope and reverse transcriptase reaction to produce permanently oncoronavirus type c after exogenous infection with rauscher leukemia virus (rlv). sindbis virus (sv) was inoculated into virogenic cultures 398 days after infection with rlv. the system in characterized by rapid (3-21 days) disappearance of the infectious arbovirus from the medium and the cells, long-term (over 5 mont ...197878589
[immune ascitic fluids in rats to the sindbis virus].data are presented concerning preparation of universal immune ascitic fluid (iaf) to sindbis virus possessing a high activity and specificity in different serological tests: cft, hi, nt, agdpt, and direct immunofluorescence test. the advantages of rat iaf over the serum of these animals consists in a higher specific activity, lower amount of nonspecific hemagglutination inhibitors and waste protein substances. rat iaf may be used for production of highly specific diagnostic preparations.197878592
[comparison of double triple integration systems]. 197880887
solid phase indirect radioimmunoassays for the rapid diagnosis of sindbis virus antigen.indirect radioimmunoassays have been developed for the rapid detection of sindbis virus. dilutions of sindbis virus from tissue culture fluids have been immobilized and allowed to react with rabbit anti-sindbis virus antibodies. the bound antibodies were assayed either by 125i-labelled anti-rabbit igg-antibodies or alternatively by addition of human complement and 125i-labelled anti-human c1q antibodies or 125i-labelled protein a.197884855
isolation of sindbis virus 26 s rna by cdna-cellulose chromatography. 197986459
interactions of retroviruses with chemical carcinogen. i. noncovalent binding of unactivated polycyclic aromatic hydrocarbons. 197989755
priming increases the amount of interferon mrna in poly(ri).poly(rc)-treated l cells.priming by mouse interferon pre-treatment resulted in an accumulation of interferon mrna in poly(ri).poly(rc)-treated l cells, starting early in the period of interferon synthesis. on electrophoresis, the priming activity of an interferon preparation co-migrated with the antiviral activity, which suggests identity of the functional principle(s) for these activities.197994345
h-2-linked control of cytotoxic t-cell responsiveness to alphavirus infection. presence of h-2dk during differentiation and stimulation converts stem cells of low responder genotype to t cells of responder phenotype.secondary tc cells generated against sindbis virus (sin) are restricted to dk. all other h-2k or d regions tested show low specific responsiveness. f1 hybrids between low and high responders show dominance of responsiveness but lack complementation. when balb/c (kdiddd) low responder fetal liver stem cells were allowed to mature in irradiated high responder recipients c3h.oh (kdiddk) a response to dk plus sin could be generated with tc cells of balb/c origin. this result, together with the failu ...1979107264
[comparative antiviral and interferonogenic activity of natural and synthetic interferon inducers in vitro and in vivo].biological activities of the rna replicative form of phage f2, a natural interferon inductor and poly-i -- poly-c, a synthetic polyribonucleotide complex were studied comparatively. differences in the comparative interferonogenic and antiviral activity of the inductors were as dependent on the type of the cell system. it was shown that deae-dextran increased the interferon-inducing activity of rff2 in the cell culture by 4 to 8 times. the dynamics of the interferonogenic and antiviral activity o ...1979110250
regulation of the interferon system: evidence that vero cells have a genetic defect in interferon production.a clone of vero cells was isolated and shown to be totally unable to synthesize interferon and insensitive to the toxic effect of poly(ri).poly(rc) treatment. cells of this clone and mouse l cells were fused by treatment with polyethylene glycol or sendai virus. hybrid cell clones were isolated following selection in medium containing hypoxanthine, thymidine and ouabain. the hybrids were sensitive to the antiviral effect of poly(ri).poly(rc) and synthesized mouse, but not primate, interferon. i ...1979113494
comparison of the structural properties of sindbis and semliki forest virus nucleocapsids.the envelope spikes of sindbis and semliki forest virus are arranged in a t = 4 icosahedral surface lattice and, by deduction, it has been suggested that the nucleocapsid proteins are similarly arranged. after treatment of the virions with a non-ionic detergent the released nucleocapsids sediment in sucrose gradients at about 160s and 150s and have densities in cscl of 1.42 g/ml and 1.425 g/ml, respectively, for sindbis and semliki forest virus. at ph 6.0 sindbis nucleocapsids do not contract li ...1979118237
adoptive transfer of cross-protection among alphaviruses in mice requires allogeneic stimulation.cell-mediated (t-effector cell) immunity is proposed as playing the major role in cross-protection between sindbis and semliki forest viruses, which are alphaviruses that do not elicit cross-neutralizing antibodies. in adoptive transfer experiments, t-cells from spleens of sindbis virus-immunized mice were found to confer specific cross-protection to semliki forest virus upon recipient mice. this cross-protection was observed in the outbred icr strain of mice and when transfers were made between ...1979157981
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
[kyzylagach virus (family togaviridae, genus alphaviruses), a new arbovirus isolated from culex modestus mosquitoes trapped in the azerbaijani ssr].a strain of leiv 65a virus was isolated in 1969 from culex modestus mosquitoes collected in the kyzylagach preserve, the azerbaijan ssr, in a colony of ciconiiformes birds. investigations of the antigenic properties of this virus by the complement fixation and neutralization tests as well as by electron microscopy showed it to belong to alphaviruses of the togaviridae family. kyzylagach virus had one-way relations with sindbis virus. some biological and biophysical-biochemical properties of the ...1979159565
effect of sindbis birus infection on survival of mice in the cold.mice infected with 10(9) plaque-forming units (pfu) of sindbis virus 9 h prior to exposure to cold (5 degrees c) died more rapidly after entering the new environment than saline-injected control mice. the early deaths occurred in animals singly housed without bedding and only when food was withheld. because deaths could be prevented by providing the infected animals with food, it was concluded that metabolic alteractions resulting from the virus infection were responsible for the deaths. as evid ...1979159887
studies of herpes simplex virus and interferon in human gingival cell cultures.cultures of human gingival fibroblast cells from patients with a positive or negative history of recurrent herpes simplex virus (hsv) infection were compared with respect to susceptibility to hsv infection and interferon activity. there was a possible inverse relationship between interferon sensitivity of gingival fibroblast cells and a clinical history of recurrent disease. no correlation was found between prior infection and other parameters of interferon activity or susceptibility of the cell ...1975163902
assembly of viruses. 1975164048
comparative study of the protein kinase associated with animal viruses. 1975166492
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
role for cell-mediated immunity in the resistance of mice to subcutaneous herpes simplex virus infection.the role of cell-mediated immunity in the resistance of young adult mice to subcutaneous herpes simplex virus (hsv) type i infection was studied in mice receiving immunosuppressive doses of antilymphocyte sera (als) or antithymocyte sera (ats). the effectiveness of these treatments to reduce cell-mediated responses was measured by their ability to prolong the life of allografts transplanted to als- or ats-treated mice. it was found that subcutaneous infection of these mice with hsv resulted in s ...1975166926
failure of attenuated temperature-sensitive influenza a (h3n2) virus to induce heterologous interference in humans to parainfluenza type 1 virus.the present investigation was undertaken to determine if a candidate live vaccine virus, influenza a/hong kong/68-ts-1 [e] (h3n2), induced heterologous interference against an interferon-sensitive, wild-type, parainfluenza type 1 challenge virus. the parainfluenza virus was administered 7 days after hong kong/68-ts-1 [e] virus infection. the clinical response, daily quantitative virus shedding, interferon production, and serum and nasal wash antibody responses were determined in an experimental ...1975166929
buoyant density sedimentation of macromolecules in sodium iothalamate density gradients. 1975167175
streptovirudins, new antibiotics with antibacterial and antiviral activity. i. culture taxonomy, fermentation and production of streptovirudin complex.a new antibiotic complex has been isolated from cultures of streptomyces strain no. ja 10124. on the basis of taxonomic studies, the producing microorganism is described as streptomyces griseoflavus (krainsky, 1914) waksman et henrici, 1948, subsp. thuringiensis subsp. nov., type strain ja 10124. the antibiotic complex, designated as streptovirudin, was isolated from extracts of both mycelium and culture filtrate. it is a white amorphous material which consists of ten closely related components ...1975168173
fluoroimidazoles as antiviral agents and inhibitors of polynucleotide biosynthesis. 1975169446
sindbis virus inhibits phosphatidylcholine biosynthesis in bhk-21 cells.sindbis virus inhibits the incorporation of [methyl-3h]choline into the phospholipids of bhk-21 cells and also inhibits the activity of the enzyme that catalyzes the final reaction involved in phosphatidylcholine biosynthesis (cytidine diphosphate-choline:1,2-diacylglycerol cholinephosphotranferase; ec
sulfated components of enveloped viruses.the glycoproteins of several enveloped viruses, grown in a variety of cell types, are labeled with 35so4(-2), whereas the nonglycosylated proteins are not. this was shown for the hn and f glycoproteins of sv5 and sendai virus, the e1 and e2 glycoproteins of sindbis virus, and for the major glycoprotein, gp69, as well as for a minor glycoprotein, gp52, of rauscher leukemia virus. the minor glycoprotein of rauscher leukemia virus is more highly sulfated, with a ratio of 35so4- [3h]glucosamine abou ...1975170420
[in vitro evaluation of antiviral inhibitors by means of a turbidity method (author's transl)].the paper presents a photometric method for the determination of virus-induced alterations (cytopathogenic effects) of cells based on nephelometric analysis. these were taken at varying time intervals after infection and with different multiplicity of infection. it was demonstrated that suppression of virus-induced cpe by the known inhibitors could also be followed by turbidity measurements. the in vitro experiments were carried out in the 2 following virus-cell-systems: pseudorabies virus in ch ...1975171906
murine cytomegalovirus: induction of and sensitivity to interferon in vitro.moderate amounts of viral inhibitor were produced by mouse embryo (me) cultures infected with two strains of plaque-purified murine cytomegalovirus (mcv). this inhibitor was shown to be interferon, based on the possession of similar properties. the growth studies of mcv in me cells showed that interferon was produced as early as 4 h after infection, infectious virus was produced between 12 to 16 h, and cytopathic effect was produced between 16 to 18 h. since mcv-induced interferon production and ...1975172448
prevalence of antibodies to arboviruses in egypt. results of a serologic survey among 1,113 university students. 1975173201
inhibition of cellular protein synthesis by simultaneous pretreatment of host cells with fowl plague virus and actinomycin d: a method for studying early protein synthesis of several rna viruses.a method is described for analysis of viral protein synthesis early after infection when minute amounts of viral proteins are effectively concealed by large amounts of produced host-specific proteins. the method is superior to a radioimmune assay, since all virus-induced proteins can be measured independent of their immunological reactivity. host-specific protein synthesis can be suppressed by infection with fowl plague virus. addition of actinomycin c 1.25 h postinfection does not prevent this ...1975173875
growth of enveloped rna viruses in a line of chinese hamster ovary cells with deficient n-acetylglucosaminyltransferase activity.sindbis and vesicular stomatitis viruses were grown in a line (termed 15b) of chinese hamster ovary (cho) cells that is deficient in a specific udp-n-acetyl-glucosamine:glycoprotein n-acetylglucosaminyltransferase. both viruses replicated normally in the cell line, but the glycoproteins of the released virus migrated faster on sodium didecyl sulfate-polyacrylamide gels than did glycoproteins of virus grown in parent cho cells. digestion of the viral glycoproteins with pronase followed by gel fil ...1975173886
virus-dependent glycosylation.the oligosaccharides of the membrane glycoproteins of sindbis virus, vesicular stomatitis virus, and rous sarcoma virus were compared on the basis of apparent size and sugar composition. it appears that each virus acquires a different set of oligosaccharides during growth in a single type of cell.1975173894
the spectrum of virus resistance of a kb cell strain resistant to diphtheria toxin. 1976176795
[identification of a hemadsorbing agent discovered in uninfected mouse l cell cultures and also the same cultures chronically infected with sindbis virus].electron microscope examinations of continuous lines of mouse l cells, both uninfected (l-init) and chronically infected with sindbis virus (l-sv) revealed accumulations of ribonucleoprotein strands and virions corresponding by their parameters to paramyxoviruses in the cytoplasms of the cells. further studies showed l-init and l-sv cell lines to have a manifest hemadsorption effect which could be completely inhibited by antiserum to parainfluenza sv5 virus. immunofluorescence procedures detecte ...1976176821
the effect of tilorone hydrochloride on the growth of several animal viruses in tissue cultures.tilorone hydrochloride, at a concentration of 10 mug/ml inhibits the growth of herpes simplex virus type 1 in bs-c-1 cells. the growth of vaccinia virus in bs-c-1 cells is partially inhibited; however, six viruses containing rna, including four members of the togavirus group grown in chick fibroblasts, are not affected by the drug. the inhibition of the growth of herpes virus by tilorone hydrochloride is greater when the multiplicity of infection is lower than 1 p.f.u/cell and when the drug is a ...1976177724
the susceptibility of isolated guts from various species of mosquito to some arboviruses.isolated guts cultured in vitro from aedes aeaegypti and ae. togoi were more susceptible to infection by sin, sf, chik and wn viruses than tissue similarly cultured from anopheles gambiae and an. stephensi. langat tp 64, a tick-borne virus, failed to infect any of the cultured mosquito tissues.1976178280
mapping of poly(a) sequences in the electron microscope reveals unusual structure of type c oncornavirus rna molecules.we have synthesized a convenient electron microscope label for mapping poly(a) sequences. short lengths of poly(dt) are polymerized onto nicked circular sv40 dna with the enzyme terminal deoxynucleotidyl transferase. an rna or dna molecule of interest is treated with glyoxal, hybridized briefly with the poly(dt) circles, and spread for microscopy; poly(a) stretches are clearly marked because they are attached to the poly(dt) on the easily recognized sv40 duplex circles. the rnas of several type ...1976182376
[stick-plaque test--an economic method of quantitative determination of viruses].an economic method for quantitative assay of viruses is presented. in this "canule stick-plaque test" (german abbreviation spt) samples of viruses, geometrically diluted and taken up by a canule, are inoculated by sticking into monolayer cell cultures overlayed with agar medium. a plaquelike cpe detectable by neutral red staining develops in the area of the inoculation. the frequency of this cpe formation depends on the concentration of viruses in the inoculated dilution. this dose-response allo ...1976186533
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
production of interferon in human diploid cell cultures.eleven human diploid cell lines were compared for their ability to produce interferon in response to newcastle disease virus. sensitivity of the cultures of mm, sindbis vsv and vr viruses was also studied. human cells derived from various tissue of a single embryo responded variably to interferon inducer. using selected viruses interferon production was studied in two systems, in cultures of leukocytes and in human embryonic cells.1976187142
enhanced resistance of mice to infection with langat (tp21) virus following pre-treatment with sindbis or semliki forest virus.significant protection to heterologous i.c. challenge with the flavovirus langat occurred after a single i.c. injection of avirulent strains of the alpha viruses semliki forest or sindbis given 1 day to 5 weeks before challenge. some protection also occurred after an i.p. infection with these viruses. we consider that the protection afforded by the alpha viruses is due to interference with the multiplication of langat virus and is related to the maximum level of brain infectivity reached in the ...1976187719
[stich-plaque test--an economic method for quantitative determination of viruses].an economic method for quantitative assay of viruses is presented. in this "canule stick-plaque test" (german abbreviation spt) samples of viruses, geometrically diluted and taken up by a canule, are inoculated by sticking into monolayer cell cultures overlayed with agar medium. a plaquelike cpe detectable by neutral red staining develops in the area of the inoculation. the frequency of this cpe formation depends on the concentration of viruses in the inoculated dilution. this dose-response allo ...1976188946
tunicamycin inhibits glycosylation and multiplication of sindbis and vesicular stomatitis viruses.tunicamycin (tm), an antibiotic that inhibits the formation of n-acetylglucosamine-lipid intermediates, thereby preventing the glycosylation of newly synthesized glycoproteins, inhibits the growth of sindbis virus and vesicular stomatitis virus in bhk cells. at 0.5 mug of tm per ml, the replication of both viruses is inhibited 99.9%. noninfectious particles were not detected. all the viral proteins were synthesized in the presence of tm, but the glycoproteins were selectively altered in that the ...1977189071
the protease inhibitor p-nitrophenyl-p' -guanidinobenzoate inactivates sindbis and other enveloped viruses. 1977190790
sindbis virus messenger rna: the 5'-termini and methylated residues of 26 and 42 s rna. 1977193248
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
variables affecting viral plaque formation in microculture plaque assays using homologous antibody in a liquid overlay.a liquid antibody microculture plaque assay and the variables that govern its effectiveness are described. the assay is based on the principle that low concentrations of homologous antibody can inhibit secondary plaque formation without inhibiting formation of primary plaques. thus, clear plaques that followed a linear dose response were produced. the assay was found to be more rapid, less cumbersome, and less expensive than assays using agar overlays and larger tissue culture plates. it was rep ...1977194918
sindbis virus-induced cytopathic effect in clones of aedes albopictus (singh) cells. 1977196393
viral receptors and their role in host and tissue specificity. 1975197866
[interaction of sindbis virus with a culture of cells producing oncornavirus].electron microscopy and biophysical methods were used for examinations of primarily trypsinized chick fibroblast cell culture spontaneously producing c-type oncornavirus at 1, 6, and 24 hours after inoculation with sindbis virus. during the first 6 hours rapid maturation and release of oncornavirus from cells were observed. at later intervals oncornavirus production was inhibited. it is assumed that in the system under study, biosynthesis of oncornavirus and sindbis virus occur separately.1977198967
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
impaired intracellular migration and altered solubility of nonglycosylated glycoproteins of vesicular stomatitis virus and sindbis virus.tunicamycin, an antibiotic which prevents the glycosylation of newly synthesized proteins, inhibits the replication of both vesicular stomatitis virus and sindbis virus. in tunicamycin-treated infected cells, all of the viral proteins are synthesized but the glycoproteins are devoid of carbohydrate. the nonglycosylated glycoproteins could not be detected on the outside of the plasma membrane by lactoperoxidase labeling, indirect immunofluorescence staining, or chymotrypsin treatment of intact ce ...1977200626
[serum-treatment in the rubella hi-test by menas of silicic acid (author's transl)].the serum treatment for the removal of nonspecific inhibitors in the rubella hi-test with silicic acid was investigated by means of isolated lipoproteins and after a micromethod by means of sindbis-virus. reduction of the three classes of lipoproteins after treatment with silicic acid was good. in the sindbis hi-test only 2% of the sera showed low titers after treatment. the method proved to be a reliable tool as removal of unspecific inhibitory activity is concerned.1977201128
studies on the occurrence and distribution of hi antibodies against some arboviruses in the serum of domestic mammals in puglia.the virological and serological studies previously carried out on arboviruses in italy are reviewed. the presence of antibodies to 11 arboviruses was investigated in the serum of various domestic animals (100 horses, 107 pigs, 102 sheep, 205 goats, 100 cattle and 200 dogs) from some areas of puglia. the techniques are described. the results, given in tables and discussed in detail, support the hypothesis that in this region also there are arboviruses circulating, particularly those of group b.1977201546
virus production with a newly developed microcarrier system.primary cell cultures as well as established lines have been grown on a recently developed microcarrier configuration that overcomes the problem of toxicity attendant on earlier developments in this technology. virus yields from these cells propagated on the new microcarriers have been measured. microcarrier-grown cells, when compared to roller-bottle-grown cells, gave virus yields on a per-cell basis that varied from slightly greater with the sindbis virus-chinese hamster ovary cells and polio- ...1977202193
the influence of immunization on the production of interferon in vivo and in vitro.the present study was undertaken to compare the production of interferon by immunized mice in response to different viral inducers. porton mice were immunized with ndv or a/wr11/57 virus by injecting 6-week-old animals with virus on days 1, 7, and 14. the interferon response was investigated 3 weeks later. compared with controls, the a-immunized mice after stimulation in vivo, produced more interferon when ndv was used as inducer. it was shown in sera as well as in washings of peritoneal cells. ...1977202218
proposal for a common oligosaccharide intermediate in the synthesis of membrane glycoproteins. 1977202393
virus infection of murine teratocarcinoma stem cell lines. 1977202395
endoribonuclease activity associated with animal rna viruses.a specific endoribonucleolytic activity was detected when detergent-lysed vesicular stomatitis of sendai virus was incubated with the precursor to escherichia coli trna tyr. the cleavage products produced and the characteristics of the reaction were similar to those previously reported for human kb cell rnase nu. like rnase nu, the virus-associated reaction generates 5'-hydroxyl and 3'-phosphate groups at the cleavage sites. at protein concentrations similar to those used to test vesicular stoma ...1978202740
[antiviral effects of alpha-trihalogenomethylamines and their derivatives]. 1977202821
arboviruses in birds captured in slovakia.virus neutralizing (vn) antibodies against sindbis, tick-borne encephalitis (tbe), west nile (wn), tahyna and calovo viruses were found in birds captured in slovakia. in parallel, sindbis, tbe and wn viruses were isolated from the blood, brain and liver of migrating birds.1977203628
[potential virostatics. 1. quinoxalines]. 1977203954
5' nucleotide sequence of sindbis viral rna.the 5' sequence of sindbis viral rna is m (7)g(5') pppapupgp...1975173879
synthesis of sindbis virus complementary dna by avian myeloblastosis virus rna-directed dna polymerase.sindbis virus 42 s rna was efficiently transcribed into complementary dna (cdna) by avian myeloblastosis virus alphabeta dna polymerase using oligo- (dt) or single-stranded calf thymus dna as primers. both of the sindbis virus cdna products were able to protect 60% of 125i-labeled sindbis virus rna, at near equal weight ratios, from rnaase a and t1 digestion. using hybridization kinetics, the crt 1/2 value for hybridization of the calf thymus-primed cdna product with excess sindbis rna was deter ...197878725
morphogenesis of sindbis virus in cultured aedes albopictus cells.cultured mosquito cells were found to produce sindbis virus nearly as efficiently as bhk-21 cells at 28 c. in virtually all of the cells observed in the electron microscope, virus morphogenesis was found to occur within complex vesicular structures which developed after viral infection. viral nucleocapsids were first seen in these vesicles and appeared to be enveloped within these structures. the process of envelopment within these inclusions differed in some respects from the process previously ...1975170422
a comparison of brain lysosomal enzyme activities in four experimental togavirus encephalitides. 1978204753
[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
antiviral effects of amphotericin b methyl ester.the methyl ester of amphotericin b (ame) is water soluble, retains antifungal activity, and is significantly less toxic in mammals than amphotericin b. in contrast to amphotericin b, which is not water soluble, ame exhibits antiviral effects against vesicular stomatitis virus, herpes simplex virus types 1 and 2, sindbis virus, and vaccinia virus in a plaque reduction assay. no antiviral effects could be demonstrated against the unenveloped adenovirus type 4 or echovirus type 11. the extent of vi ...1978206201
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
[viral co-carcinogenesis and other aspects of viral interaction]. 1978209638
length of glycoprotein spikes of vesicular stomatitis virus and sindbis virus, measured in situ using quasi elastic light scattering and a resistive-pulse technique. 1978213892
efficient transfer of interferon-induced virus resistance between human cells.the rate of development of interferon-induced virus resistance in a mixture of two human cell types (u and wish) is determined by the cell type (wish) in the mixture which responds first. this phenomenon has been shown with two types of interferon assay procedure, and with both vesicular stomatitis virus and sindbis virus. the transfer of virus resistance from one human cell (wish) to another (u) (homospecific transfer) is much more efficient than the transfer from mouse l cells to wish cells (h ...1978214520
the entry into host cells of sindbis virus, vesicular stomatitis virus and sendai virus.we have compared the mechanisms of entry into host cells of three enveloped viruses: sendai virus, vesicular stomatitis virus (vsv) and sindbis virus. virus entry by membrane fusion should antigenically modify the surface of a newly infected cell in such a way that it will be killed by anti-viral antibody and complement. on the other hand, virus entry by a mechanism involving uptake by the cell of the whole virion should not make cells sensitive to antibody and complement. as expected, cells new ...1978215317
[characteristics of the response of mice with temporary immunodepression to the administration of live or inactivated vaccine against tick-borne encephalitis].mice with immunity defects caused by administration of cyclophosphane were inoculated with an inactivated vaccine or langat virus (tp-21 strain) considered to be an approximate model of the vaccine against tick-borne encephalitis. in mice with depressed immune response, the asymptomatic infection caused by langat virus turns into acute form and encephalitis with a fatal outcome develops in 86--100%. pre-treatment with inactivated tick-borne encephalitis vaccine did not protect the animals with t ...1979217179
complete exchange of viral cholesterol.the exchange of the cholesterol in the membranes of two enveloped viruses, sindbis virus and vesicular stomatitis virus, with cholesterol present in lipid vesicles and in serum was measured. biosynthetically labeled viral cholesterol underwent spontaneous and complete transfer to both lipid vesicles and to serum. the rate with which and the extent to which this process occurred were very similar for these two viruses. during incubation with lipid vesicles in excess, half of the viral cholesterol ...1979217416
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