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the role of atp in the biogenesis of vaccinia virus mrna in vitro. 1978664258
relation of poly(adenosine diphosphoribose) synthesis to dna synthesis and cell growth.a permeable cell technique has been used to measure the synthesis of dna and poly(adenosine diphosphoribose) (poly(adpr)) in mouse l cells subjected to different perturbations of cell growth. cells leaving log phase growth and entering plateau phase, showed a decrease in dna synthesis and an associated increase in intrinsic poly(adpr) synthesis. in contrast to the variations in intrinsic poly(adpr) synthesis, the total poly(adpr) synthesis activity, measured in the presence of added dnaase, rema ...1978667059
effect of methylation of the n6 position of the penultimate adenosine of capped mrna on ribosome binding.an rna(2'-o-methyladenosine-n6)-methyltransferase isolated from hela cells was used to convert the ends of vaccinia virus mrnas containing m7g(5')pppam-to m7g(5')pppm6am-. under competitive conditions, there was no preferential binding of mrnas containing m6am residues within the capped ends relative to those containing am either to wheat germ ribosomes at 70 mm potassium acetate or to reticulocyte ribosomes at 120 mm potassium acetate. only at high concentrations of potassium acetate (200 mm) a ...1978670177
sequence complexity and relative abundance of vaccinia virus mrna's synthesized in vivo and in vitro.the sequence complexity and relative abundance of vaccinia virus mrna's, synthesized in vivo and in vitro, have been measured by dna-rna hybridization. up to 42% of [3h]thymidine-labeled virus dna can be protected from digestion with nuclease s1, a single-strand specific nuclease, after annealing to excess polyadenylylated mrna obtained at 7 h after infection. in contrast, only 26% of vaccinia virus dna is protected when hybridized to polyadenylylated rna obtained at 2 h after infection in the p ...1978671583
heat inactivation of vaccinia virus particle-associated functions: properties of heated particles in vivo and in vitro.the heat inactivation characteristics of several vaccinia virus particle-associated functions known to be involved in the transcription of the genome were examined. all functions were more resistant to heat than infectivity. noninfectious particles were generated which exhibited significant levels of activity of all enzymes examined, and their properties were investigaed both in vitro and in vivo. rna was synthesized in vitro by such particles, although transport of the rna into the surrounding ...1978671584
5'-terminal 7-methylguanosine and mrna function. the effect of enzymatic decapping and of cap analogs on translation of tobacco-mosaic-virus rna and globin mrna in vitro.1. decapped tobacco mosaic virus (tmv) rna and rabbit globin mrna were prepared by enzymic treatment of rnas with nucleotide pyrophosphatase purified from potato. the extent of removal of 5'-terminal 7-methylguanosine 5'-monophosphate (m7gmp) from tmv rna was at least 97% as estimated by labeling of the 5' termini in vitro with s-adenosyl[methyl-3h]methionine catalysed by vaccinia virus methyltransferases. 2. the effect of enzymic decapping was compared with the effect of cap analogs on mrnas tr ...1978729595
antiviral activity of extracts from marine algae.extracts of two species of marine algae, constantinea simplex and farlowia mollis, were tested for antiviral activity in tissue culture and in experimental infections of mice. treatment of confluent mouse embryo fibroblast cell monolayers with either compound before viral inoculation was effective in inhibiting the replication of herpes simplex virus type 1 and type 2, vaccinia virus, and vesicular stomatitis virus, but not encephalomyocarditis virus, semliki forest virus, or murine cytomegalovi ...1978686707
purification of mrna guanylyltransferase from vaccinia virions.gtp:rna guanylyltransferase, the enzyme which catalyzes the guanylylation of the 5' termini of viral mrnas, has been isolated and purified approximately 10,000-fold from cores of vaccinia virus. s-adenosyl-methionine:mrna (guanine-7)-methyltransferase copurified with guanylyltransferase activity through chromatography on dna agarose, phosphocellulose, and centrifugation in glycerol gradients, suggesting that the two activities are closely associated. the molecular weight of native guanylyltransf ...1978659428
characteristics of reactions catalyzed by purified guanylyltransferase from vaccinia virus. 1978659429
an analysis of the mpb-arrested stage during replication of vaccinia virus in hela cells. 1978743288
synthesis of some newer formazans and tetrazolium salts as antiviral agents.thirteen new formazans were prepared by the condensation of the phenylhydrazone of 3.4-dimethoxy-6-nitro-veratraldehyde with the appropriate phenyl diazonium salts. attempts were made to oxidize these highly coloured formazans with various oxidizing agents to their corresponding tetrazolium salts. the most suitable oxidizing agent was found to be h2o2/fe2+. both the formazans and tetrazolium salts were screened for their antiviral activity against the ranikhet disease virus and vaccinia virus in ...1978746062
effect of uv irradiation on the expression of vaccinia virus gene products synthesized in a cell-free system coupling transcription and translation.the effect of uv irradiation on the expression of the vaccinia virus genome was investigated in a cell-free system coupling transcription with translation. exposure of vaccinia virus to an increasing dose of irradiation resulted in differential reduction in the syntheses of virus-specified polypeptides in the coupled system, with sensitivity being proportional to the size of the gene pro duct. this suggests that each translationally functional mrna species produced in vitro by vaccinia virus cor ...1978671585
soluble endoribonuclease activity from vaccinia virus: specific cleavage of virion-associated high-molecular-weight rna.a soluble endoribonuclease activity was extracted from purified vaccinia virus cores by treatment with sodium-deoxycholate and dithiothreitol. the soluble enzyme readily cleaved purified virion-associated high-molecular-weight rna to limit-sized fragments sedimenting at 8 to 12s. purified virion-released 8 to 12s polyadenylated mrna was not degraded by the enzyme extract. the soluble endoribonuclease did not require the presence of ribonucleoside triphosphates for activity.1978671588
measles and vaccinia antibodies in multiple sclerosis. 1978671683
[the virostatic effect of adenine-arabinoside monophosphate. experimental findings and preliminary clinical experiences].adenine arabinoside (ara-a), a synthetic nucleoside, is an antiviral agent, which is effective against poxviruses and viruses of the herpes group. the monophosphate (ara-amp) has the great advantage of better solubility, compared to the parent compound. experimental studies show the outstanding effect of ara-amp on the encephalitis by vaccinia-virus in white mice. even after immunesuppression by total body irradiation, the survival rate of the ara-amp treated animals was significantly higher com ...1978680620
analysis of the methylated 'cap' structures of vaccinia mrna by two-dimensional thin-layer chromatography.two different twodimensional cellulose thinlayer separations for blocked, methylated mrna 5'-termini are described. they allow rapid analysis even of complex mixtures of mrna "cap" structures on the basis of their methyl group content and base composition. these simple procedures are especially useful for the analysis of [3h-methyl]-labeled mrna in combination with tritium fluorography. a qualitative and quantitative analysis of the methylated "cap" structures of in vitro labeled vaccinia "core" ...1978683182
effect of double-stranded rna associated with viral messenger rna on in vitro protein synthesis. 1978687583
biogenesis of poxviruses: glycolipid metabolism in vaccinia-infected cells. 1978619485
biogenesis of vaccinia: isolation of conditional lethal mutants and electron microscopic characterization of their phenotypically expressed defects. 1978622807
procedure for purification of intact dna from vaccinia virus.a procedure for the isolation of intact vaccinia dna molecules by chromatography on hydroxyapatite in the presence of 6 m urea is described. when lysates of virions containing 0.5 to 10 microgram of dna were employed, over 95% of the viral dna could be recovered free of poteins. vaccinia dna molecules isolated in this manner sedimented at 68s in neutral sucrose gradients and had an average contour length of 62.3 micrometer when examined in an electron microscope, and the dna could be cleaved wit ...1978621785
clinical and immunological study of percutaneous revaccination in children who originally received smallpox vaccine subcutaneously.in a large multicenter smallpox vaccination study carried out from 1970 to 1973, it was found that 39% of children who were initially immunized by the subcutaneous route and then challenged percutaneously with a standard vaccination did not have measurable neutralizing antibody upon follow-up. because of this finding, a percutaneous revaccination study was conducted at the st. louis study center in 1975 and 1976. there were four study groups, which were composed on the basis of route of primary ...1978632346
observations on the effects of formaldehyde on cockroaches and their flora: i. survival of vaccinia virus-infected cockroaches during fumigation with formaldehyde.in these studies it is shown that the common "british" and "american" adult cockroaches can survive exposure to formaldehyde fumigation carried out at double the strength and for four times as long as is recommended for disinfection of rooms. it is further reported that vaccinia virus ingested prior to the fumigation survives in the cockroach gut and may be excreted up to 5 days later. since cockroaches are ubiquitous and are to be found in most hospitals, laboratories and animal houses, these f ...1978563890
serologic and cross-immunity studies with contagious ecthyma and goat pox virus isolates from the western united states.contagious ecthyma and goat pox viruses were isolated from goats affected with papulopustular epidermal lesions. results of in vitro serum neutralization and in vivo cross-immunity studies indicate that these contagious ecthyma and goat pox isolates from the western united states are antigenically dissimilar and that exposure or vaccination with one isolate could not be used as a method of inducing immunity to the other. exposure to each isolate conferred immunity to re-exposure with the same ag ...1978565197
decreased lymphocyte transformation to vaccinia virus in multiple sclerosis.lymphocyte transformation to vaccinia virus was measured in multiple sclerosis (ms) patients and normal controls. there was a significant reduction of lymphocyte transformation to vaccinia virus in multiple sclerosis patients compared with the control group. in addition, a positive correlation existed between the degree of disability of the multiple sclerosis patients and the extent of lymphocyte transformation in the presence of vaccinia virus. there was no correlation between cell-mediated imm ...1978565482
particle heterogeneity in vaccinia virus populations during passage. 1978644883
[production of temperature-sensitive mutants of vaccinia virus with the aid of nitrosomethylurea, and their preliminary characteristics].the possibility of using nitrosomethylurea for production of one-hit temperature-sensitive (ts) mutants of vaccinia virus suitable for genetic and biochemical studies was explored. the effect of nitrosomethylurea on replicating dna of the virus produced 26 ts mutants, the effectiveness of mutagenesis being 10%. in recombination experiments with 12 of them it was shown that all the mutants under study had single ts defects of the genome. all ts mutants were capable of synthesizing dna under nonpe ...1978565563
[rna transcripts of both strands of viral dna in cells infected with vaccinia virus].denaturated 3h-thymidine-labeled vaccinia virus dna was hybridized with an excess of "late" virus-specific rna isolated from virus-infected chick embryo cell cultures 8 hours postinfection. the percentage of dna converted into dna-rna hybrid under these conditions never exceeded 50%. if the rna preparation had been self-annealed prior to hybridization, the percentage was decreased slightly. on the other hand, if the self-annealed rna had been treated with rn-ase and the double-stranded dna-rna h ...1978569925
[specific cytolytic activity of human lymphocytes following vaccination with vaccinia virus and measles virus].human peripheral lymphocytes harvested 7 days after vaccination with vaccinia virus or measles virus lyse specifically target cells infected with the corresponding virus. this cytotoxic activity is found in a subpopulation of lymphocytes depleted of t-cells and containing lymphocytes bearing fc receptor. the activity can also be transferred by supernatant of immune lymphocytes on addition of normal lymphocyte. these results suggest that two types of cell are involved: an antibody-secreting cell ...1978571140
[attempts to activate virus replication in cell cultures]. 1978571668
in situ assay of poxvirus-induced and virion-contained deoxyribonucleases in dna polyacrylamide gels.cowpox virus and vaccinia virus wr specific dnases were identified by an in situ assay using dna-containing acrylamide gels. a dnase present in the isolated virions of strain cowpox and vaccinia wr was identified. its properties as determined by the in situ assay resembled those of the well-characterized dnase v1. the assay was also used to follow the time course of 'acid' dnase induction by cowpox virus in primary chick embryo fibroblasts.1978621135
impaired defense against vaccinia in a child with t-lymphocyte deficiency associated with inosine phosphorylase defect.a case of progressive vaccinia associated with a profound deficiency of cellular immunity and a defect in inosine phosphorylase is described. a striking contrast was observed between humoral immunity, which showed little if any impairment, and a severe cellular defect affecting both markers and functions of t lymphocytes. the child died despite treatment with methosazone, levamisole, transfer factor, irradiated blood transfusions, and a thymus graft. an adequate serum level of antibody to vaccin ...1978416187
interferon enhances the fragility of lysosomes in l-929 mouse fibroblasts.infection of interferon-treated l-929 mouse fibroblasts with vaccinia wr virus is followed by severe cytolysis within 3 to 4 h. it is shown that this cytolysis cannot be caused by enzymes released from lysosomes into the cytosol. however, there is evidence that homologous interferon has a noxious effect on lysosomes. this phenomenon appears to be another aspect of the anticellular functions of interferon.1978418151
host range restriction of vaccinia virus in chinese hamster ovary cells: relationship to shutoff of protein synthesis.chinese hamster ovary cells were found to be nonpermissive for vaccinia virus. although early virus-induced events occurred in these cells (rna and polypeptide synthesis), subsequent events appeared to be prevented by a very rapid and nonselective shutoff of protein synthesis. within less than 2 h after infection, both host and viral protein syntheses were arrested. at low multiplicities of infection, inhibition of rna synthesis with cordycepin resulted in failure of the virus to block protein s ...1978310474
the lymphoreticular system in triggering virus plus self-specific cytotoxic t cells: evidence for t help.the thymus determines the spectrum of the receptor specificities of differentiating t cells for self-h-2; however, the phenotypic expression of t cell's specificity for self plus virus is determined predominantly by the h-2 type of the antigen presenting cells of the peripheral lymphoreticular system. furthermore, virus specific helper t cells are essential for the generation of virus-specific cytotoxic t cells. for cooperation between mature t cells and other lymphocytes to be functional in chi ...1978305460
[resistance of serratia marcescens to an etbylene oxide-methyl bromide mixture and the possibility of using it to control the effectiveness of disinfectant measures].the authors studied the serratia marcescens (strain no. 851) resistance to the okćbm mixture by the method of test objects in comparison with the vaccine virus (strain b-51) at a temperature of 20, 30, and 40 degrees c. resistance of the mentioned bacteria to the okćbm mixture proved to be somewhat greater than that of the vaccine virus at 20 and 30 degrees c, whereas at 40 degrees c their resistance was found to be practically identical. this permits to use serratia marcescens to control the ef ...1978352054
studies on the mechanisms of vaccina virus cytopathic effects. i. inhibition of protein synthesis in infected cells is associated with virus-induced rna synthesis.the mechanism of vaccinia virus-induced inhibition of protein synthesis was studied in llc-mk2, hela and l cells. removal of cycloheximide (300 microgram/ml) from cells infected at a multiplicity of infection (m.o.i.) of 300 particles/cell at 4 h after infection resulted in the resumption of both host and virus protein synthesis in llc-mk2 cells, but not in hela and l cells. in order to determine whether virus-induced rna synthesis, which occurs in infected cells in the presence of cycloheximide ...1978307049
activation of reticuloendothelial system macrophages and enhancement of host resistance to a transplantable osteogenic sarcoma in mice by an extract of brucella abortus.an aqueous-ether extract of brucella abortus, bru-pel, enhanced resistance of mice to a transplantable osteogenic sarcoma (ogs). the results presented in this report suggest that bru-pel is an effective immunomodulator and that one mechanism through which it enhances host resistance is activation of phagocytic cells of the reticuloendothelial system. peritoneal macrophages from mice inoculated with bru-pel 14 days previously were cytotoxic for ogs cells in vitro, limited the multiplication of va ...1978282007
visualization of an inverted terminal repetition in vaccinia virus dna.an inverted terminal repetition was observed in dna molecules extracted from vaccinia virus. the repeated sequence was visualized by (i) nicking the hairpin loops present of the ends of vaccinia virus dna, (ii) separating the strands of dna by alkali denaturation, (iii) allowing the single strands to self-anneal, and (iv) examining the dna with an electron microscope. single-stranded circular molecules, each of which contained a duplex projection (3.54 +/- 0.12 micron) representing the terminal ...1978283397
immune effector cell activity in canines: failure to demonstrate genetic restriction in direct antiviral cytotoxicity.experiments were undertaken to establish whether the cytotoxic activity of canine immune effector cells against viral antigens was affected by the genotype of the target cell (genetic restriction). puppies from three different breeds were infected with vaccinia virus, and the peripheral blood leukocytes were collected at various times for measurement of their cytotoxicity against autologous and heterologous vaccinia virus-infected and uninfected skin fibroblasts. in all cases cytotoxicity only o ...1978304843
[local reaction and neutralization test in smallpox vaccination after previous inoculation with mva. stickl's graduated vaccination (author's transl)].of 200 first inoculations and 8 revaccinations, the sera were examined for content of neutralizing vaccine antibodies 3 weeks after the mva graduated inoculation. in spite of imponderables which affect the failure rate in the "clinical trial", a positive result was obtained on first vaccination in 85%. in vaccinated children with a negative neutralization test a distinct booster effect was obtained with a "main vaccination" after about six months. the same effect was seen with revaccinations. fo ...1978307672
inhibition of host protein synthesis in vaccinia virus-infected cells in the presence of cordycepin (3'-deoxyadenosine).cordycepin inhibited efficiently viral mrna and polyadenylic acid syntheses in vaccinia virus-infected cells, but allowed the shutoff of host protein synthesis to occur. therefore, cordycepin was used to study this shutoff in the absence of gene expression. ribosome transit time was increased in infected cells, revealing an inhibition at the level of elongation and/or release of polypeptide chains. however, the disappearance of heavy polysomes in vaccinia virus-infected cells showed that the inh ...1978304489
[production of antiserum for preparation of fitc-conjugated immunoglobulins intended for poxvirus detection].the experience of using sheep as donors of hyperimmune smallpox antiserum produced by immunization with vaccinia virus grown in the homologous tissue is described. in the preparatory stage of immunization four intravenous or intramuscular injections of a low dose of the antigen were used. subsequently, as the need in the serum arose (10--14 days before) the animals were given a "hit" dose of the antigen (20 ml) intravenously. with this immunization schedule it was possible to obtain smallpox ant ...1978358600
effect of human fibroblast interferon on vaccination in volunteers. 1978342530
on the thymus in the differentiation of "h-2 self-recognition" by t cells: evidence for dual recognition?in the thymus, precursor t cells differentiate recognition structures for self that are specific for the h-2k, d, and i markers expressed by the thymic epithelium. thus recognition of self-h-2 differentiates independently of the t cells h-2 type and independently of recognition of nonself antigen x. this is readily compatible with dual recognition by t cells but does not formally exclude a single recognition model. these conclusions derive from experiments with bone marrow and thymic chimeras. i ...1978305459
meningeal exudate cells in vaccinia meningitis of mice: role of local t cells.intracerebral inoculation of vaccinia virus into adult ddd mice produced intensive meningitis several days after infection. the inflammatory reaction could be quantitated by counting cells obtained from this inflammatory lesion. the local virus titer increased until day 5 and subsequently decreased rapidly with time. concomitant with this titer decrease, numerous meningeal exudate cells appeared in the lesion. the cytotoxic activity of these cells against vaccinia virus infected cells was studie ...1978352957
[why does tetanus not occur among brazilian amerindians of the amazon region? a critical analysis of the problem and the elements involved]. 1978368946
[differences in the repair activity of cells from inbred strains of mice following exposure to the chemical carcinogen--4-nitroquinoline-1-oxide]. 1978415853
the influence of some thiosemicarbazone derivatives with antiviral activity on immune response in mice.the aim of the present study was to examine the influence of the thiosemicarbazone-group of compounds with antiviral activity on the humoral and cellular immune response in r iii, cba and balb/c mice, immunized with sheep erythrocytes or sensitized with oxazolon. the plaque forming cells test, according to jerne's method and the oxazolon hypersensitivity test were performed. all of the examined compounds, inhibited the humoral immune response, and three of them decreased also the cellular respon ...1978749807
use of vaccinia virus as an adjuvant in inducing specific anti-tumour immunity to transplantable mouse fibrosarcoma. i. adaptation of the virus to mouse tumour cells as a pre-requisit for adjuvanticity. 1978757683
use of vaccinia virus as an adjuvant in inducing specific anti-tumour immunity to transplantable mouse fibrosarcoma. ii. rejection of tumour graft 'in vivo' humoral and lymphocytotoxicity 'in vitro'. 1978757692
concanavalin a-mediated cell agglutinability induced by vaccinia virions. 1978741652
mrna(nucleoside-2'-)-methyltransferase from vaccinia virus. purification and physical properties.an s-adenosyl-l-methionine:mrna(nucleoside-2'-)-methyltransferase, one of at least three activities required for the 5'-terminal modification of mrna, has been purified from vaccinia virus particles. employing brome mosaic virus rna ending in m7g(5')pppg- as substrate, a simple deae-cellulose filter assay measuring the incorporation of methyl groups from s-adenosyl[methyl-3h]methionine to position 2' of the penultimate nucleoside was devised. starting from disrupted vaccinia virus cores, a 350-f ...1978701281
simple sensitive microbioassay for adenine arabinoside and hypoxanthine arabinoside in human plasma.previous methods using low- or high-pressure liquid chromatography and uv absorbance for quantitation of arabinosides in plasma can practically detect only >/=200 ng of adenine arabinoside and >/=100 ng of hypoxanthine arabinoside per ml, and they require expensive equipment and expert technical assistance. we describe in this report a simple quantitative microbioassay for arabinosides in human plasma based on their ability to inhibit the cytopathic effect of vaccinia virus in an adenosine deami ...1978742879
specific secretion of polypeptides from cells infected with vaccinia virus.the pattern of polypeptides specifically secreted by cells after infection with vaccinia virus has been analyzed. a complex pattern of apparently virus-specified polypeptides exhibiting temporal control of the type seen with intracellular polypeptides after virus infection was observed. some of the specifically secreted polypeptides were shown to be modified by glycosylation and sulfation. the possible significance of these results is discussed.1978731794
the effect of mixed infections induced by adenovirus type 5 and vaccinia virus, on the ultrastructure of kb cells. i. ultrastructure of kb cells infected with adenovirus type 5 and vaccinia virus (within a period of 24--72 hours). 1978708935
identification and characterization of ribosomal proteins phosphorylated in vaccinia-virus-infected hela cells.two-dimensional analysis of 32p-labelled ribosomal proteins revealed three proteins which are phosphorylated in vaccinia-virus-infected hela cells. all three proteins belong to the 40-s ribosomal subunits and were identified as s2, s6 and s16. the ribosomal protein s6 is phosphorylated also in uninfected hela cells. phosphoserine was detected in all three proteins, phosphothreonine only in the protein s2. phosphorylation of these ribosomal proteins in infected cells is dependent on the multiplic ...1978710442
atp-independent dna synthesis in vaccinia-infected l cells.mouse l cells can be made permeable to exogenous nucleotides by a cold shock in 0.01 m tris . hcl ph 7.8, 0.25 m sucrose, 1 mm edta, 30 mm 2-mercaptoethanol and 4 mm mgcl2. dna synthesis in permeabilized l cells requires atp whereas dna synthesis in permeabilized l cells that are infected with vaccinia virus is atp-independent. permeabilized l cells that are infected with ultraviolet-irradiated virus show a marked suppression of dna synthesis which is not corrected by an excess of deoxynucleosid ...1978718913
histological and ultrastructural changes in experimentally produced post-vaccinial lymphadenitis in rabbits.light and electron microscopic alterations in lymph nodes after intradermal vaccinia virus inoculation are described. in the early stages the lymph nodes show a diffuse lymphoreticular proliferation associated with the appearance of peculiar large cells called reticulolymphoblasts. this appearance can be mistaken for malignant lymphoma. later on, these changes are replaced by markedly hypertrophied lymphoid follicles which persist for long periods. these alterations can be mistaken for follicula ...1978722407
generation of virus-specific cytolytic activity in human peripheral lymphocytes after vaccination with vaccinia virus and measles virus.human peripheral blood lymphocytes (pbl) harvested after vaccination with vaccinia or measles virus showed a specific activity against virus-infected target cells. this activity peaked on day 7 and was specific for the target cells infected with the virus used for the vaccination. the cytotoxic activity was not related to hla markers. the cells involved in the cytolytic process were lymphocytes bearing fc receptors. in addition, the cytotoxic activity was abrogated by more than 90% by rabbit fab ...1978723792
expression of vaccinia virion surface tubule protein as a virus specific cell surface antigen.the sequential expression of a vaccinia virus specific antigen on the surface of infected cells has been followed by 125i-labelled anti-vaccinia igg. after an initial drop (during the first 30 minutes of infection) the amount of viral antigen at the cell surface increased steadily for the 12 hours tested. the expression of the antigen was found to depend on protein and rna synthesis from the start, but dependent on dna synthesis only after 4 hours. the senitivity of the phenomenon to ultraviolet ...1978727948
absence of detectable capping and methylating enzymes in influenza virions.in the presence of mg(2+) and a specific dinucleotide primer (apg or gpg), the influenza virion transcriptase synthesizes the eight discrete segments of complementary rna (crna) containing polyadenylic acid (plotch and krug, j. virol. 21:24-34, 1977). virions were examined for their ability to cap and methylate crna containing di- or triphosphorylated 5' termini. by using the primers ppapg, pppapg, or ppgpg, viral crna was synthesized in vitro with [alpha-(32)p]-gtp and s-[methyl-(3)h]adenosylme ...1978702657
vaccinia virus transcription: hybridization of mrna to restriction fragments of vaccinia dna. 1978664221
structure of vaccinia dna: analysis of the viral genome by restriction endonucleases. 1978664234
replication of vaccinia dna in mouse l cells. iv. protein synthesis and viral dna replication. 1978664237
formation of vaccinia virus dna-protein complex in the presence of isatin beta thiosemicarbazone (ibt).the association of newly synthesized vaccinia virus dna with proteins in infected hela cells was followed. a shift from a high density to a low density complex occurred between 3 and 6 h after infection. this process was not affected by isatin beta thiosemicarbazone (ibt), an inhibitor of pox virus growth. at 22 h after infection in the absence of ibt, mature virions of high density were observed; however, in the presence of the drug, high density dna-protein complexes, which lack the two main v ...1978690618
[cytogenetic study of the effect of vaccinia virus on cells from embryo and adult mice].after immunization with vaccinia virus an increase in frequency of aneuploids and secondary chromosomal constrictions is observed in adult mice. moreover, an increased frequency of chromosomal aberrations was demonstrated. the increase in the number of secondary chromosomal constrictions indicates an activation of nucleolar-organizing regions.1978684811
adsorption and penetration of enveloped and naked vaccinia virus particles.the adsorption and penetration of intracellular naked vaccinia virus (inv) and extracellular enveloped vaccinia virus (eev) were examined. the adsorption kinetics of inv and eev were similar, but inv adsorption was found to be more sensitive to the adsorption environment than eev. the pfu-to-particle ratio for the two virus particles indicated that eev was approximately two times as infectious as inv. kinetic studies at 37 degree c showed that eev penetrated cells more rapidly than inv. penetrat ...1978691111
polypeptide composition of extracellular enveloped vaccinia virus.extracellular enveloped vaccinia (eev) virus grown in sirc and in hela cells was purified by consecutive equilibrium centrifugations in sucrose and cesium chloride gradients. a higher degree of purity was obtained with virus material prepared in sirc cells. the polypeptides of purified eev and inv (intracellular naked vaccinia) virus were compared in polyacrylamide slab gel electrophoresis. three proteins (200,000 molecular weight [200k], 95k, and 13k) detected in hela-derived inv were absent in ...1978691112
multiple roles for atp in the synthesis and processing of mrna by vaccinia virus: specific inhibitory effects of adenosine (beta,gamma-imido) triphosphate.adenosine (beta,gamma-imido)triphosphate (amp-pnp) and guanosine (beta,gamma-imido)triphosphate (gmp-pnp) are analogs of atp and gtp with non-hydrolyzable gamma-phosphates. although both amp-pnp and gmp-pnp were used in place of atp and gtp by escherichia coli rna polymerase to transcribe vaccinia virus dna, only gmp-pnp was used by the transcriptase present within vaccinia virus cores. amp-pnp specifically prevented initiation of transcription, since rna initiated in the presence of atp, gtp, a ...1978691115
simultaneous assay for mrna (guanine-7-)-methyltransferase and mrna(2'-o-nucleoside)methyltransferase of purified vaccinia (wr) virions. 1978697020
mrna(nucleoside-2'-)-methyltransferase from vaccinia virus. characteristics and substrate specificity.an mrna(nucleoside-2'-)-methyltransferase purified from vaccinia virus was shown to methylate the penultimate nucleoside of rna ending in m7g(5')pppn-. by contrast, rnas ending in pn-, ppn-, or even g(5')pppn- are not methyl acceptors. this specificity indicates that 2'-o-methylation is the final step in the formation of the m7g(5')pppnm- cap structure. both adenosine and guanosine are methylated, in accordance with the presence of these nucleosides in the penultimate position of vaccinia virus ...1978701282
inactivation of cytomegalovirus and semliki forest virus by butylated hydroxytoluene.butylated hydroxytoluene (bht) is an antioxidant that is widely used in foods because it prevents spoilage by delaying degradation of lipid components. this hydrophobic compound inactivated human and murine cytomegalovirus (cmv) and semliki forest virus (sfv). both human and murine cmv were inactivated more than 90% by 40 microgram of bht/ml after incubation for 1 hr at 37 c. under the same conditions, svf was inactivated about 75%, whereas poliovirus, which does not contain lipid membrane as a ...1978210237
synthesis and antiviral acticity of some phosphates of the broad-spectrum antiviral nucleoside, 1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamide (ribavirin).1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamide 5'-phosphate (2) was prepared and converted into the following derivatives: the 5'-phosphoramidate 3, the 5'-diphosphate 4, the 5'-triphosphate 5, and the cyclic 3',5'-phosphate 6. the cyclic 2',3'-phosphate 7 was prepared from the parent nucleoside, 1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamide (1), and was opened to the 2'(3')-phosphate 8. these compounds were found to exhibit significant antiviral activity against several viruses in ce ...1978211234
inverted terminal repeats in rabbit poxvirus and vaccinia virus dna.in both rabbit poxvirus and vaccinia virus dna have demonstrated an identical distribution of eight hinfi. the length of the terminal repeats was found to be 3.4 to 3.6 megadaltons (mdaltons) for rabbit poxvirus dna and 7.4 to 8.0 mdaltons for vaccinia virus dna. maps of the hinfi restriction sites within isolated ecori end fragments of rabbit poxvirus and vaccinia virus dna phave demonstrated an identical distribution of eight hinfi sites in an internal part (approximately 2 mdaltons) of the ec ...1978212601
activation of endogenous type c virus in balb/c mouse cells by herpesvirus dna.several virion and nonvirion dnas were tested for the ability to activate endogenous type c virus in balb/c-derived mouse cells using the calcium precipitation technique. the dnas from all herpesviruses tested activated xenotropic type c virus synthesis. these included dnas from herpes simplex virus types 1 and 2, epstein-barr virus, human cytomegalovirus, sa8 virus, infectious bovine rhinotracheitis virus, pseudorabies virus, and herpes saimiri virus (m-dna). in contrast, dnas from vaccinia vir ...1978212761
the use of cytochalasins in studies on the molecular biology of virus--host cell interactions.in conclusion, one can say that the cytochalasins--in their brief history of application in virology--have proven to be valuable tools in studies on the molecular biology of virus--host cell interactions. on the other hand, viral systems can be useful in defining the primary sites of action of cytochalasins in certain cells. in interpreting the effects of cytochalasins on virus replication, however, one must take into consideration that the cytochalasins exert a wide variety of alterations in ce ...1978208877
attachment of herpes simplex virus to neurons and glial cells.cells of brain tissue of rabbits, rats and mice were dissociated and glial cells, neuronal perikarya and synaptosomes were separated by centrifugation on discontinuous ficol gradients. hsv was shown to attach well to rat and rabbit glial cells and synaptosomes but not to neuronal perikarya. of intracerebrally infected mice the fractions with glial cells contained the infective virus. the interactions between hsv and neuronal cells and the implication of the observations on the hsv infection of t ...1978211185
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
enhanced virus replication in mammalian cells exposed to commercial emulsifiers.mammalian cell cultures were used to show that a variety of commercial emulsifiers are capable of enhancing the sensitivity of these cells to infection with several viruses. some emulsifiers were not active as enhancers, and those viruses that responded to the enhancing emulsifiers were single-stranded ribonucldic acid viruses. the double-stranded viruses that were tested were nonresponders.1978205172
multiple sclerosis: cellular and humoral immune responses to several viruses.one hundred and eight multiple sclerosis (ms) patients and 108 matched controls were studied for antibody levels and cellular immune responses to several viruses. there were significant increases in the mean titers of complement fixation (cf) or hemagglutination inhibition (hi), and complement-mediated cytotoxicity (cmc) tests for measles antibodies in ms patients; there was no increase in antibody titers to herpesviruses 1 and 2, or cytomegalovirus (cmv). the direct migration inhibition (dmi) t ...1978206860
immunological studies of heat-labile virus inhibitors. i. specificity of absorption onto sensitive viruses and specific response after virus infections.heat-labile virus inhibitor (hli) in normal sera of various mammalian species capable of neutralizing variola (vrv) and newcastle disease viruses (ndv) was studied immunologically. after sucrose density gradient centrifugation of guinea pig serum, the hli activity against vrv and that against ndv were both demonstrated in the same region sedimenting fastor than igm. absorption with partially purified vrv or ndv removed the hli activity on the homologous virus but not that on the other. prior sat ...1978207952
[antiviral effect of aqueous plant extracts in tissue culture].the aqueous extracts from 178 kinds of medicinal plants belonging to 69 families were examined from the point of their virustatic activity against herpes-, influenza-, vaccine- and poliovirus. 75 kinds proved to be virustatic against one or more kinds of virus. nearly one-third of the active plants belong to families that are known as especially rich in tannin. besides the virustatic activity a great number of extracts showed also a cytostatic activity.1978204315
characterization of a dna-binding phosphoprotein from vaccinia virus replication complex. 1978208247
increased resistance of trisomic-21 cells to virus replication: role of interferon. 1978208250
(s)-9-(2,3-dihydroxypropyl)adenine: an aliphatic nucleoside analog with broad-spectrum antiviral activity.(s)-9-(2,3-dihydroxypropyl)adenine, a novel nucleoside analog, the sugar moiety of which is replaced by an aliphatic chain, inhibits the replication in vitro of several dna and rna viruses, including vaccinia, herpes simplex (types 1 and 2), measles, and vesicular stomatitis. it is also effective in vivo in reducing the mortality rate of mice inoculated intranasally with vesicular stomatitis virus.1978205946
resistance of visna virus to interferon.visna is a slow infection of sheep caused by a retrovirus. the persistence of virus despite the immune response of the host is best explained by restricted genetic expression of the virus and consequently prolonged periods of residence inside cells. the purpose of this investigation was to determine whether the restriction in genetic expression of visna virus is mediated by interferon. sheep interferon induced by polyriboinosinic-polyribocytidylic acid in fetal lambs inhibited the growth of herp ...1978213502
[suppression of viral reproduction by means of specific action on the cell]. 1978212895
[inactivation of viruses in water by anodic oxidation (author's transl)].the inactivating effect of anodic oxidation on viruses performed in an experimental electrolytic polarization unit was investigated with 11 different viruses suspended in tap and superficial water. furthermore attempts were made to define the influence of factors important in experimental and water respect. using concentrations up to 10(4) infectious units per ml representing a multiple quantity of the virus demonstrable in contaminated environmental waters all the viruses investigated could be ...1978211753
ir-genes in h-2 regulate generation of anti-viral cytotoxic t cells. mapping to k or d and dominance of unresponsiveness.h-2 dependent and virus-specific ir genes regulate the generation of primary virus-specific k or d restricted cytotoxic t-cell responses in vivo. the following examples have been analyzed in some detail: first, dk restricted responses to vaccinia in sendai viruses are at least 30 times lower than the corresponding k-restricted responses irrespective of the h-2 haplotypes (k, b, d, dxs, dxq) of k and i regions; in contrast, lcmv infection generates high responses to dk. these findings are consist ...1978212503
permeability changes of plasma and lysosomal membranes in hela cells infected with rabbit poxvirus.infection of hela-cell monolayer cultures with rabbit poxvirus induces a marked decrease in cell-associated protein and in the activities of lactate dehydrogenase, acid phosphatase, and beta-glucuronidase. this effect begins to occur around 10 hours post-infection (p.i.) and is accompanied by a concomitant rise of these enzyme activities in the culture medium. only few cells detach from infected monolayers and these cannot account for protein release. virion release can be inhibited at 4 degrees ...1978215105
peritoneal macrophage activation indicated by enhanced chemiluminescence.a number of studies have demonstrated the ability of various bacterial preparations, protozoa, and chemicals to activate macrophages and concomitantly to enhance host resistance to both tumors and infections. recently, viral infections have been shown to have a similar effect upon macrophage function. to better define the metabolic state of activated macrophages, we have evaluated the ability of peritoneal cells (pc) from vaccinia virus- or murine cytomegalovirus-infected or corynebacterium parv ...1978213391
enzymatic conversion of 5'-phosphate-terminated rna to 5'-di- and triphosphate-terminated rna.we have isolated from vaccinia virus cores an enzyme, 5'-phosphate-polyribonucleotide kinase, that in the presence of atp and mg2+ catalyzes the conversion of 5'-phosphate and 5'-diphosphate termini of rna to the 5'-triphosphate species. with the exception of datp, other nucleoside triphosphates were inactive as phosphate donors; activity with datp was 10% of that observed with atp. the purified enzyme did not phosphorylate 5'-hydroxyl- or 5'-monophosphate-terminated polydeoxyribonucleotides, al ...1978217000
lymphocyte-mediated cytotoxicity in humans during revaccination with vaccinia virus.fifteen healthy human volunteers were revaccinated with vaccinia virus. blood samples (4 to 7) were obtained during the 3 weeks after revaccination. peripheral blood lymphocytes were washed extensively and tested for cytotoxicity against vaccinia-infected autologous and/or homologous skin fibroblasts. without addition of antibodies, peak levels of killing were observed on days 7 to 9. the killing did not depend on common hla markers. on days with peak activity, extensively washed lymphocytes sho ...1978213386
differential inhibitory effects of 5-bromodeoxyuridine on vaccinia and monkeypox viruses.replication of vaccinia and monkeypox viruses was impeded in the presence of 5-bromodeoxyuridine (budr) in rl-33 cells derived from rabbit lung tissue. the different degree of inhibition was found among strains of those viruses, in which it was evident that five strains (cv-1, lister, ihd, dairen-i and ikeda) of vaccinia viruses resulted in more reduced yields of infectious virus than four strains (sen-19, orang utan, copenhagen and sierra leone) of monkeypox viruses. there was also strain varia ...1978212474
vaccination against pox diseases under immunosuppressive conditions.pox diseases, caused either by smallpox virus or zoonotic pox viruses or animals, continue to be of potential danger to a non-vaccinated population. mass vaccinations will become necessary and will then also be administered to persons with immunological aberrations. the vaccines which are presently used against smallpox cause severe complications in such hosts. in contrast, the attenuated vaccinia virus strain mva is safe even under the conditions of immunosuppression and is recommended for the ...1978223909
5-propyl-2'-deoxyuridine: a specific anti-herpes agent.in both primary rabbit kidney cells and human skin fibroblasts, 5-propyl-2'-deoxyuridine proved inhibitory to herpes simplex virus at a concentration as low as 1 micrograms/ml, whereas concentrations higher than 200 micrograms/ml were required to inhibit vaccinia virus replication or normal cell metabolism.1978233730
studies on the polypeptides of poxvirus. i. comparison of structural polypeptides in vaccina, cowpox and shope fibroma viruses.radioactively labeled vaccinia, cowpox and shope fibroma virions free from any detectable contamination with host cell protein, were dissociated into their constituent polypeptides, and these were then analyzed by sds-polyacrylamide gel electrophoresis and autoradiography. the profiles of constituent polypeptide bands of four strains of vaccinia virus (ihd-w, ihd-j, lister and dis) were almost the same, except that a polypeptide of about 41,000 daltons was not detectable in the autoradiogram of ...1978219840
in vitro inhibition of protein synthesis by purified cores from vaccinia virus.the mechanism of the shutoff of cellular protein synthesis in vaccinia virus-infected cells has been investigated by using in vitro systems. purified vaccinia cores cause inhibition of endogenous mrna translation in nonpreincubated reticulocyte lysates and ehrlich ascites tumor cell-free systems. translation of viral mrna from turnip yellow mosaic virus is also impaired in wheat germ cell-free extracts. the block induced by vaccinia cores in protein synthesis is not due to a decrease in the avai ...1978272632
studies of rna isolated from piptoporus betulinus as interferon inducer.crude rna isolated from piptoporus betulinus and two fractions of it obtained after the chromatography contain single-stranded rna. the crude rna, but not its chromatographic fractions, are resistant to the pancreatic rna-ase. the crude preparation of rna from p. betulinus contains beside ribose, considerable amounts of glucose, galactose and mannose. the crude rna from p. betulinus induces in the human fibroblasts interferon with specific activity of 400 units per mg of protein.1978219808
studies on the polypeptides of poxvirus. ii. comparison of virus-induced polypeptides in cells infected with vaccinia, cowpox and shope fibroma viruses.virus-induced polypeptides in cells infected with vaccinia, cowpox and shope fibroma viruses were examined by sds-polyacrylamide gel electrophoresis followed by autoradiography. at least 42 vaccinia virus-induced polypeptides were identified among the polypeptides of cells pulse-labeled with [35s]-methionine and/or of fractionated cells labeled with [14c]-leucine for 24 hr. they consisted of 15 polypeptides (early polypeptides) which were synthesized even in the presence of cytosine-1-beta-d-ara ...1978219843
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