Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| the antiviral activity of ribosomal polynucleotides against encephalomyocarditis virus infection of mice. | intraperitoneal administration of ribosomal rna (rrna) was found to protect mice against subsequent lethal infection by encephalomyocarditis (emc) virus without induction of detectable amounts of circulating interferon. the nature of this effect was examined in terms of the types of natural polyribonucleotides which could afford such protection. rrna prepared from e. coli was slightly more effective than chicken liver rrna which was, in turn, more effective than yeast rrna. 5s ribosomal rna was ... | 1980 | 6160832 |
| role of 2',5'-oligo(adenylic acid) polymerase in the degradation of ribonucleic acid linked to double-stranded ribonucleic acid by extracts of interferon-treated cells. | rna covalently linked to double-stranded rna (dsrna) is preferentially degraded in extracts of interferon-treated hela cells [nilsen, t. w., & baglioni, c. (1979) proc. natl. acad. sci. u.s.a. 76, 2600-2604]. the size of the dsrna required for this preferential degradation has been determined by annealing poly(i) of known length to the poly(c) tract of encephalomyocarditis virus (emcv) rna or by annealing poly(u) to poly(a) of known length of vesicular stomatitis virus mrna. the dsrna must be lo ... | 1980 | 6161640 |
| rapid, quantitative, semiautomated assay for virus-induced and immune human interferons. | an improved human interferon (if) assay is described. this procedure is based on the ability of encephalomyocarditis virus to replicate in wish cell microcultures with the production of discrete plaques in the presence of a liquid tissue culture medium. performance of 50% plaque reduction endpoint assays in micro-culture required only 0.1 ml of specimen for determinations using duplicate dilutions beginning at 1:3. semiautomated equipment facilitated simultaneous in situ dilution and distributio ... | 1980 | 6163794 |
| dissociation of interferon effects on murine leukemia virus and encephalomyocarditis virus replication in mouse cells. | two subclones of swiss mouse cells infected with moloney murine leukemia virus (m-mulv) were tested for their response to interferon (ifn). whereas m-mulv production in the two subclones was inhibited to the same extent, one of the subclones was significantly more sensitive to ifn when the antiviral effect was measured by replication of encephalomyocarditis (emc) virus. the same subclone was also more sensitive to the anticellular activities of ifn. additionally, nih 3t3 cells infected with m-mu ... | 1981 | 6163874 |
| ribosomal rna cleavage, nuclease activation and 2-5a(ppp(a2'p)na) in interferon-treated cells. | ribosomal rna (rrna) in intact ribosomes is cleaved into discrete products on incubation of reticulocyte lysates or l-cell extracts with ppp(a2'p)3a. cleavage of rrna may, therefore, provide a useful assay for 2-5a (ppp)a2'p)na; n = 2 to 4) or for the presence of a 2-5a-dependent nuclease. the results with reticulocyte lysates differed from those obtained in the l-cell-free system in that (a) a different rna cleavage pattern was produced (with added l-cell ribosomes) and (b) cleavage was fully a ... | 1981 | 6164990 |
| regulation of 2'5'-oligo(a) polymerase activity in quiescent human fibroblasts treated with interferon. | 1981 | 6166120 | |
| virus-specific interferon action. protection of newborn mx carriers against lethal infection with influenza virus. | the efficacy of interferon in antiviral protection of newborn mice differing at the mx locus was investigated. adult mice bearing the allele mx exhibit a high degree of specific resistance toward lethal challenge with influenza viruses. in contrast, newborn mx carriers are virtually as susceptible to influenza viruses as newborn mice devoid of mx. resistance can be abrogated by treating adult animals with anti-interferon serum. here, we provide direct evidence of a virus-specific effect of inter ... | 1981 | 6166723 |
| studies on the mode of action of single-stranded polynucleotides which are antiviral against encephalomyocarditis virus infection of mice. | poly(di) and poly(dc) administered separately or sequentially show no antiviral effects against emc virus infection of mice, whereas poly(ri) and poly(rc) are antiviral in such treatment regimens without evidence of interferon induction. the antiviral effects of poly(ri) and poly(rc) appear to depend on single-strandedness because their antiviral effects are decreased by annealing to poly(dc) and poly(di) respectively. this decrease in antiviral effect would not seem to be due to an adverse effe ... | 1981 | 6168248 |
| translational elongation rate changes in encephalomyocarditis virus-infected and interferon-treated cells. | infection of mouse l cells with encephalomyocarditis virus results in a rapid inhibition of host protein synthesis before the synthesis of viral proteins. although no alterations in initiation factor activities have been demonstrated in encephalomyocarditis virus-infected mouse cells, a defect in polypeptide chain elongation has been shown to occur in infected cell extracts. we investigated the significance of this elongation defect in the host shutoff phenomenon in vivo. average polypeptide cha ... | 1981 | 6168777 |
| the effect of experimental infection of mice with encephalomyocarditis (emc) virus on interferon production by alveolar and peritoneal cells in vitro. | after infection of mice with emc virus, dose-dependent increase or decrease of the synthesis of in vitro newcastle disease virus (ndv)-induced interferon was observed in alveolar and peritoneal cells. it was shown that peritoneal cells from mice with mild course of the infection (infecting dose 0.2-1.0 ld50 per mouse) produce interferon in vitro on the same level as the control cells. alveolar cells isolated from the same mice shortly after infection exhibited increased interferon production in ... | 1981 | 6169322 |
| a mouse cell line, which is unprotected by interferon against lytic virus infection, lacks ribonuclease f activity. | a mouse cell line, nih 3t3, does not respond to some of the activities of interferon. even after treatment with high concentrations of interferon the replication of lytic viruses, such as encephalomyocarditis virus (emcv) and vesicular stomatitis virus (vsv) is not inhibited in these cells. in contrast, interferon treatment of these same cells results in the inhibition of moloney murine leukemia virus (mmulv) production. we have analyzed enzymatic pathways which are induced by interferon in thes ... | 1981 | 6169526 |
| specific high-affinity binding of 125i-labeled mouse interferon to interfevon resistant embryonal carcinoma cells in vitro. | 1981 | 6170161 | |
| protein synthesis and membrane integrity in interferon-treated hela cells infected with encephalomyocarditis virus. | the survival of interferon (ifn)-treated cells after encephalomyocarditis (emc) virus infection depends on both the concentration of interferon and the multiplicity of infection (m.o.i.) used. the cell survived emc infection if a high ifn/m.o.i. ratio was used in the experiment, whereas cell death took place at low ifn/m.o.i. ratios, even if ifn is also present during infection. analysis by polyacrylamide gel electrophoresis of the proteins synthesized in ifn-treated cells subsequently infected ... | 1981 | 6170728 |
| growth inhibitory effect of mouse interferon in transformed cells. | 1981 | 6171141 | |
| antiviral activities of hybrids of two major human leukocyte interferons. | four hybrid human leukocyte interferon (leif or ifn-alpha) genes have been constructed by in vitro recombination of leif-a (ifn-alpha 2) and leif-d (ifn-alpha 1) genes at common restriction endonuclease sites located within their coding regions. these hybrid genes have been expressed in e. coli under trp promoter control. the interferons produced [leif-ad (bglii), -ad (pvuii), -da (bglii), -da (pvuii)] have antiviral properties distinct from the parental molecules leif-a and -d, varying consider ... | 1981 | 6171779 |
| antiviral activity of bacteria-derived human alpha interferons against encephalomyocarditis virus infection of mice. | bacteria-derived human leukocyte interferon (ifn) subtypes, ifn-alpha a, -alpha b, and -alpha d, and two hybrid ifns, ifn-alpha ad and -alpha da, were examined for both in vitro and in vivo antiviral activity. two of these materials in highly purified form (ifn-alpha d and -alpha d) protect mice against lethal doses of encephalomyocarditis virus infection. a single dose of 1 microgram of protein of ifn-alpha d 3 h before infection conferred protection in both bdf1 and cd-1 mice against encephalo ... | 1982 | 6173327 |
| reversal by hypotonic medium of the antiviral state induced by lymphoblastoid interferon in human hela cells. | the induction kinetics of the antiviral state in hela cells treated with human lymphoblastoid interferon (ifn) was studied. in cells treated with 4-200 u/ml ifn, the antiviral state was fully established in 7-9 h. inhibition of virus multiplication was more rapid if the concentration of ifn was increased to 1,000 u/ml. this antiviral state gradually disappeared during the 48 h after ifn removal. several compounds known to act on the cell membrane or on the cytoskeleton were tested for their infl ... | 1981 | 6173348 |
| assay of interferon by measurement of reduction of mm virus rna synthesis. | 1981 | 6173620 | |
| use of viral infections in animal models to assess changes in the immune system. | viral infections in animal models appear to be ideal systems for determining toxicity to the immune system by environmental substances. since many viral infections that are utilized in animals produce systemic disease, these models provide an opportunity to evaluate the interaction between virus and components of host resistance. in these infections it is possible to delineate the role of antibody, interferon, cell-mediated immunity, neutrophils and macrophages in response to infection. a change ... | 1982 | 6174323 |
| mechanism of antiviral action of quercetin against cardiovirus infection in mice. | oral treatment with quercetin protected abd2f1/jena mice significantly against intraperitoneal encephalomyocarditis, col, sk, mm, mengo m,l and mengom virus infections, but not against intracerebral challenge with mengom virus. enhanced resistance to mengom virus were induced in the genetically different dba 2/jena, c57bl/jena, c57bl/lati and abc2f1/jena mice, c57bl6/jena nu/nu mice were also protected, indicating that the thymus was non-essential to the protective effects of quercetin. in ab/je ... | 1981 | 6176184 |
| virus-mediated inhibition of the ppp(a2'p)na system and its prevention by interferon. | 1982 | 6176229 | |
| is a compromised interferon response an etiologic factor in reye's syndrome? | young mice injected with sublethal doses of toximul mp8, a typical commercial polyoxyethylene ether-based emulsifier, died more frequently when infected with encephalomyocarditis virus than did control mice. lymphocytes taken from emulsifier-injected mice responded poorly to interferon induction, unlike lymphocytes from control animals. interferon protected control mice against viral encephalomyocarditis, but such protection was not equally demonstrable in emulsifier-injected mice. these data su ... | 1982 | 6176306 |
| inhibition of viral replication in cell cultures treated with prostaglandin e1. | 1982 | 6177007 | |
| control of the ppp(a2'p)na system in hela cells. effects of interferon and virus infection. | hela cells have an unusually high level of ppp(a2'p)na synthetase (n = 2 to greater than or equal to 4) even in the absence of interferon treatment. in accord with this ppp(a2'p)na and ppp(a2'p)na-mediated ribosomal rna cleavage occur naturally in response to encephalomyocarditis virus infection in control as well as in interferon-treated cells. despite this, in the absence of interferon treatment, encephalomyocarditis virus grows well in these cells. a possible explanation for this paradox is t ... | 1982 | 6177533 |
| [sensitivity of a continuous cell culture of human ovarian carcinoma to interferon preparations of different origins]. | a comparative study of homologous (human) and heterologous (porcine and bovine) leukocyte interferon preparations showed them to have antiviral and antiproliferative effects on caov tumor cells culture derived from human ovary carcinoma. these effects were lower in heterologous than in homologous interferon preparations. | 1982 | 6178220 |
| human interferon suppression of retrovirus production and cell fusion, and failure to inhibit replication of encephalomyocarditis virus in rhabdomyosarcoma (rd114) cells. | 1982 | 6179291 | |
| interferon action against reovirus: activation of interferon-induced protein kinase in mouse l929 cells upon reovirus infection. | 1982 | 6179298 | |
| interferon action in human fibroblasts: induction of 2', 5'-oligoadenylate synthetase in the absence of detectable protein kinase activity. | in several strains of human fibroblasts, treatment with human alpha- or beta-interferon (ifn) resulted in an induction of 2', 5'-oligoadenylate synthetase but no protein kinase activity. the antiviral and anticellular effects of ifn are elicited in these cells in the absence of detectable ifn-induced protein kinase activity. | 1982 | 6179503 |
| platelet-derived growth factor (pdgf) inhibits antiviral and anticellular actin of interferon in synchronized mouse or human cells. | antiviral and anticellular action of purified mouse or human interferon was found to be inhibited in the quiescent, monolayer cultures of mouse or human fibroblasts (3t3 and fs-14) stimulated for growth by pdgf. in the asynchronous cell cultures the antagonistic effect of pdgf towards interferon, was much less evident. the optimal synchronization of cells for division was obtained by density inhibition and the incubation of the confluent cell monolayers in the low serum medium for 24 h and in 5% ... | 1980 | 6180044 |
| interferon-mediated antiviral state in human mrc5 cells in the absence of detectable levels of 2-5a synthetase and protein kinase. | treatment of human hela and mrc5 cells with human alpha (leukocyte) and beta (fibroblast) interferon results in the development of an antiviral state against two types of viruses: vesicular stomatitis virus (rhabdovirus) and encephalomyocarditis virus (picornavirus). these cells, however, differ in their ability to synthesize the two double-stranded (ds) rna-dependent enzymatic activities, pppa(2'p5'a)n synthetase (2-5a synthetase) and protein kinase which have been reported to be induced in sev ... | 1981 | 6180053 |
| a putative interferon induced in hamsters by poly(i) . poly(c). | encephalomyocarditis (emc) virus causes lethal infection of hamsters against which poly(i) . poly(c) causes dose-dependent protection. in contrast, no antiviral effects occur with poly(i) . poly(c) against influenza virus infection of hamsters. serum from poly(i) . poly(c) treated hamsters protects other hamsters against emc virus infection with maximum protection with serum removed 3h after poly(i) . poly(c) treatment of the donor hamsters. in such assays the factor was found to be inactivated ... | 1981 | 6180078 |
| enhancement of viral rna-induced interferon production of l cells treated with insulin and amphotericin b methyl ester. | a study was initiated to develop a more efficient method of producing high-titered l cell interferon. the induction of interferon by viral infectious rna could be augmented by pretreating the cell cultures with insulin and infecting in the presence of amphotericin b methyl ester (ambme). l cells were treated for 24 hr with different concentrations of insulin and then challenged with mm virus rna suspended in a balanced salt solution with and without ambme. the fluids were collected 48 hr after i ... | 1981 | 6180090 |
| automated, quantitative cytopathic effect reduction assay for interferon. | a rapid, cytopathic effect reduction assay for human interferon (ifn) is described. dilutions of ifn were made with an automated diluter in 96-well microtiter plates. total incubation time was 26 h. ifn titers were calculated from optical density readings of crystal violet-stained monolayers in an automated spectrophotometer, which required less than 1 min to read each plate. | 1982 | 6181091 |
| mouse genes influence antiviral action of interferon in vivo. | balb/c mice are more sensitive to the antiviral effect of interferon than c57bl/6 mice, as demonstrated by experiments involving protection against lethal infection with encephalomyocarditis virus. this greater sensitivity of the balb/c genotype to interferon action is in accord with previous observations that the bone marrow-derived erythroid precursors and macrophages of balb/c mice are more sensitive to the anti-proliferative action of interferon than those of c57bl/6 mice. an analysis of the ... | 1982 | 6183213 |
| analysis of antiviral state in rd114 and a204 cells after interferon treatment. | 1982 | 6183688 | |
| protective effect of different mouse interferons in mice infected with encephalomyocarditis (emc). | antiviral activity of various preparations of mouse interferons (mu-ifn) administered prophylactically by the intranasal route 4 h before intranasal infection of mice with emc virus was studied. in spite of the same activity of mu-ifn preparations in vitro, their antiviral effect in vivo displayed differences. the "alveolar" mu-ifn induced with ndv obtained in the upper respiratory tract, appeared to be the most effective interferon preparation in the prophylaxis of viral infection in mice. seve ... | 1982 | 6184029 |
| suppressor factors and their potential for immunotherapy, and chemical influences on interferons. | 1982 | 6184353 | |
| indomethacin and aspirin do not inhibit the antiviral or anti-proliferative actions of interferon. | neither indomethacin nor aspirin, at concentrations which inhibited the formation of prostaglandins and prevented the interferon-induced increase in the intracellular concentration of cyclic gmp, had any significant effect on the development of the interferon-induced antiviral state either in mouse l1210 cells challenged with vesicular stomatitis virus or in mice infected with encephalomyocarditis virus. furthermore, neither drug had any significant effect on the interferon-induced inhibition of ... | 1982 | 6185629 |
| [effect of a number of antitumor preparations on rna- and protein-synthesizing processes and viral interferon induction in krebs 2 ascites carcinoma cells]. | antitumor drugs: adenosine cyclophosphane, adenosine thiophosphamide, colchamine thiophosphamide, and tribetamide inhibited rna biosynthesis in krebs-ii ascitic carcinoma cells and in similar concentrations they were much less inhibiting for protein-synthesizing processes (in cells and cell-free protein-synthesizing system). the drugs could inhibit interferon synthesis, possibly after virus induction, in krebs-ii ascitic carcinoma cells only in concentrations significantly inhibiting the synthes ... | 1982 | 6186093 |
| effect of interferon on encephalomyocarditis virus infection of cultured mouse pancreatic b cells. | the m variant of encephalomyocarditis virus (emc) produces a disease similar to human insulin-dependent diabetes mellitus in some but not all strains of mice. this diabetogenic m variant was found to induce fivefold more interferon than non-diabetogenic strains of emc in cultures of mouse l 929 fibroblasts. when interferon induced by the m variant was added to monolayers of b cells from both diabetes-'susceptible' cd-1 mice and 'resistant' c57 bl/6 mice before emc infection, b cell damage and vi ... | 1983 | 6186560 |
| assessment of viral and immune factors in emc virus-induced diabetes: effects of cyclosporin a and interferon. | emc virus-induced diabetes in mice may be a model of human type i diabetes. it is postulated that auto-immune reaction plays a role in beta cell destruction after viral aggression. the use of anti-viral (interferon) or immunosuppressive drugs (cyclosporin a) could contribute to an understanding of the pathogenesis of diabetes in this model. early or late administration of cyclosporin a increased mortality and frequency of diabetes in female mice and did not influence these parameters in males de ... | 1983 | 6186814 |
| enhancement of delayed-type hypersensitivity and induction of interferon by the lipophilic agents dda and cp-20,961. | 1982 | 6187475 | |
| [properties of human alpha-interferon f and hybrid interferon f/d obtained from recombinant bacteria compared to the properties of an interferon preparation from human leukocytes]. | 1983 | 6187523 | |
| inhibition of mrna methylation: an approach to specific inhibition of viral replication. | eukaryotic mrnas and most viral mrnas contain very extensive modification on the 5' end consisting of the "cap," part of which is a guanine which is methylated in the 7-position. it is quite well established that the methylated cap is essential for the efficient translation of the mrna. in a search for an effective chemotherapeutic agent, dr. roland robins synthesized the compound ribavirin; this compound turned out to be an extraordinarily effective virostatic agent against both rna and dna vir ... | 1982 | 6187726 |
| persistence of interferon action in mouse cells permeabilized with lysolecithin. | dna synthesis, as measured by incorporation of [(3)h]ttp, was inhibited in swiss mouse 3t3 cells treated with interferon and subsequently permeabilized with lysolecithin. the degree of inhibition observed was similar in intact or permeabilized cells. the interferon-induced antiviral state was retained in permeabilized cells. | 1983 | 6187939 |
| differential antiviral effects of interferon in three murine cell lines. | infectious leukemia virus production by two chronically infected nih/mol lines was strongly inhibited by interferon treatment of the cells. the corresponding degree of inhibition in jlsv-11 cells was much lower. multiplication of encephalomyocarditis virus in all three cell lines was barely affected by interferon treatment. replication of vesicular stomatitis virus, on the other hand, was highly sensitive to interferon in the jlsv-11 line and in one nih/mol line but was practically insensitive i ... | 1983 | 6187940 |
| 2-5a(pppa2'p5'a2'p5'a) in interferon-treated encephalomyocarditis virus-infected mouse l-cells. | 1981 | 6189212 | |
| [comparative study of the biological properties of plasmid and natural human interferons]. | a comparative study of biological properties of natural and plasmid human interferons was carried out. natural and leukocyte interferons: alpha (induced by newcastle disease virus) and gamma (induced by staphylococcal enterotoxin a) as well as natural fibroblastic beta interferon induced by poly(i) x poly(c) were studied in comparison with plasmid interferons alpha-f and alpha-f/d obtained from recombinant bacteria. antigenic determinants of plasmid interferons alpha-f and alpha-f/d were found t ... | 1983 | 6189294 |
| rrna cleavage as an index of ppp(a2'p)na activity in interferon-treated encephalomyocarditis virus-infected cells. | in cell-free systems, 2-5a [ppp(a2'p)na, n = 2 to greater than or equal to 4] activates a latent endoribonuclease, the 2-5a-dependent rnase, which cleaves rrna in intact ribosomes into discrete and characteristic products (d. h. wreschner et al., nucleic acids res. 9:1571-1581, 1981). here we present northern blots which have identified the 18s or 28s origins of the cleaved products from rrna. in addition, identical 3' termini were observed for fragments of 18s rrna from a hela cell-free system ... | 1983 | 6190010 |
| tunicamycin treatment inhibits the antiviral activity of interferon in mice. | earlier we reported that tunicamycin (tm) treatment of l cells in vitro significantly enhances the antiviral activity of interferon (ifn) against viruses (such as vesicular stomatitis, sindbis, and herpes simplex) which bud from membranes. however, no such enhancement of the antiviral activity of ifn by tm was observed against encephalomyocarditis virus (emcv) (nonbudding). we were interested to know whether tm would similarly enhance the antiviral activity of ifn and ifn inducers in vivo agains ... | 1983 | 6190759 |
| regulation of the antiviral and anticellular activities of interferon by exogenous double-stranded rna. | the effects of double-stranded rna (dsrna) on interferon (ifn)-induced antiviral and anticellular activities was investigated by introducing poly(i)-poly(c) into mouse l-cells. coprecipitation of dsrna with calcium phosphate enabled its efficient penetration into cells in culture. rate of cellular protein synthesis was inhibited by dsrna only in cultures pretreated with ifn. moreover, the anticellular effect of ifn, as measured by the inhibition of cell dna synthesis, was also enhanced by dsrna. ... | 1983 | 6192322 |
| analysis of genetic variation in theiler's virus during persistent infection in the mouse central nervous system. | the genetic changes occurring in the bean strain of theiler's murine encephalomyelitis virus (tmev) during persistent infection in the mouse central nervous system (cns) were studied. rnase t1-oligonucleotide fingerprinting of the rnas of 28 bean viruses isolated at various times postinfection (p.i.) demonstrated that mutation occurred throughout the infection. although plaque-purified bean virus was used to inoculate mice intracerebrally, genetically different viruses were recovered from the cn ... | 1983 | 6192587 |
| antiviral, anticellular and enzyme-inducing activities of interferons in rd-114 cells. | rd-114 is a human sarcoma-derived cell line which is chronically infected with the rd-114 retrovirus. in a previous study, we found that treatment of these cells with human interferon-alpha or human interferon-gamma causes a marked inhibition of rd-114 virus production, but that the replication of exogenous vesicular stomatitis or encephalomyocarditis virus is not impaired. in the present study, we report that neither type of interferon has strong inhibitory effects on dna synthesis or on multip ... | 1983 | 6194249 |
| characterization of vilyuisk virus as a picornavirus. | the v-1 strain of vilyuisk virus, isolated from the cerebrospinal fluid of a chronic case of encephalomyelitis in siberia and subsequently passaged 41 times in mice, was examined to determine its serological relationship to theiler's murine encephalomyelitis virus (tmev) and encephalomyocarditis (emc) virus and some physicochemical characteristics of the virion. on the basis of virion size (28 nm), icosahedral symmetry, buoyant density (1.33 g/ml), sedimentation coefficient (150s), and capsid po ... | 1983 | 6195311 |
| [role of interferon in experimental viral diseases]. | 1983 | 6196097 | |
| modification of encephalomyocarditis virus-induced diabetes in mice by antiviral agents. | the current study used a murine model of diabetes induced by the d variant of encephalomyocarditis virus (demc) to determine the protective effect of exogenous antiviral agents. antivirals, which were found to inhibit the development of demc virus cytopathic effect in l-929 cell monolayers, were administered intraperitoneally beginning 12 h prior to demc virus challenge. arildone (500 mg/kg per day) or murine interferon (3.2 x 10(6) iu/kg per day) significantly reduced the incidence of hyperglyc ... | 1983 | 6197026 |
| antiviral and protein-inducing activities of recombinant human leukocyte interferons and their hybrids. | the antiviral activities of recombinant human leukocyte interferons ifn-alpha a and ifn-alpha d as well as five hybrids of these interferons against retroviruses, vesicular stomatitis virus, and encephalomyocarditis virus were studied in feline, human, and murine cells. although these interferon species had widely different potencies, their activities against these viruses were, in general, proportional. the ifn-alpha a/d (bgl) hybrid was the most potent species, and the ifn-alpha d/a (bgl) hybr ... | 1984 | 6200607 |
| effects of interferon and encephalomyocarditis virus on in vitro development of preimplantation mouse embryos with and without the zona pellucida. | development of preimplantation mouse embryos, with or without the zona pellucida, in the presence of interferon (ifn) and mouse encephalomyocarditis (emc) virus was studied using the in vitro culture method. the embryos (2- to 8-cell stages) were obtained from superovulated mice and cultured in modified witten's medium under paraffin oil in 5% co2 in air at 37 degrees c. removal of the zona pellucida does not affect the subsequent development of the embryos: 90% of embryos with and 87% of embryo ... | 1984 | 6205464 |
| primary structural comparison of rna-dependent polymerases from plant, animal and bacterial viruses. | possible alignments for portions of the genomic codons in eight different plant and animal viruses are presented: tobacco mosaic, brome mosaic, alfalfa mosaic, sindbis, foot-and-mouth disease, polio, encephalomyocarditis, and cowpea mosaic viruses. since in one of the viruses (polio) the aligned sequence has been identified as an rna-dependent polymerase, this would imply the identification of the polymerases in the other viruses. a conserved fourteen-residue segment consisting of an asp-asp seq ... | 1984 | 6207485 |
| an animal model of congestive (dilated) cardiomyopathy: dilatation and hypertrophy of the heart in the chronic stage in dba/2 mice with myocarditis caused by encephalomyocarditis virus. | to investigate whether lesions that develop in the chronic stage of viral myocarditis are similar to those seen in congestive (dilated) cardiomyopathy, we studied myocarditis in inbred strains of dba/2 mice infected with encephalomyocarditis (emc) virus. myocardial necrosis with calcification appeared on day 4. thereafter, myocardial necrosis became more extensive and mononuclear cell infiltration was evident and was most marked on day 14. on day 90, cellular infiltration had decreased and myoca ... | 1982 | 6212162 |
| role of interferon in the antiviral state elicited by selected interferon inducers. | 1980 | 6243412 | |
| human leukocyte interferon: separation of biologically different species by modification of carbohydrate moieties. | human leukocyte interferon was studied to determine if its antiviral (av) and growth inhibitory (gi) activities could be separated by enzymatic or chemical cleavage of carbohydrate moieties and electrophoretic procedures. the relative proportion of the two activities (av:gi ratio) was determined for each gel fraction. untreated interferon and interferon deglycosylated by glycosidases or metaperiodate were subjected to polyacrylamide gel electrophoresis in sodium dodecyl sulfate. the av:gi ratio ... | 1980 | 6243919 |
| inhibitory effects of 'cap' analogues on globin mrna and encephalomyocarditis rna translation in a reticulocyte cell-free system. | the cap analogues 7-methylguanosine 5'-phosphate [m7g(5')p], 7-methylguanosine 5'-triphosphate [m7g(5')ppp] and 2'-o-methylguanosine 5'-triphosphate [gm(5')ppp] inhibit the translation of capped globin mrna and encephalomyocarditis (emc) rna (a naturally uncapped mrna) in a reticulocyte cell-free system. this inhibition occurs at the level of protein synthesis initiation and is of a competitive type since it can be overcome by increasing the mrna concentration. however, the translation of globin ... | 1980 | 6244153 |
| nonspecific inhibition of encephalomyocarditis virus replication by a type ii interferon released from unstimulated cells of mycobacterium tuberculosis-sensitized mice. | unstimulated peritoneal cells (pc) from mice sensitized with nonviable mycobacterium tuberculosis in an oil-droplet emulsion inhibit encephalomyocarditis virus (emcv) replication in mouse embryo fibroblast monolayers. concentrations of mycobacteria ranging from 50 to 500 microgram elicit pc that inhibit emcv replication greater than 99%. pc collected 2 to 6 weeks post-inoculation of mycobacteria are most effective (greater than 99% inhibition), although cells harvested from mice 7 through 10 wee ... | 1980 | 6244349 |
| human leukocyte interferon induces 2', 5'-oligo (a) polymerase and protein kinase. | 1980 | 6244703 | |
| susceptibility to diabetogenic virus: host versus pancreatic factors. | 1980 | 6245309 | |
| palindrome-like dimers of double-stranded rna of encephalomyocarditis virus. | 1980 | 6245513 | |
| testosterone effect on experimental diabetes mellitus in encephalomyocarditis (emc) virus infected mice. | a diabetes mellitus-like disease occurs in male dba/2 mice infected with the m variant of the encephalomyocarditis virus. female mice of this strain sustain systemic infection, but rarely exhibit hyperglycaemia. the diabetogenic effects of the virus were studied in 3 groups of adult dba/2 males-castrates, castrates treated with testosterone, and sham-operated controls. after infection, pancreatic insulin concentrations decreased precipitously to approximately 10% of control values in intact male ... | 1980 | 6245984 |
| polyamines in encephalomyocarditis virus. | encephalomyocarditis virus contains approximately 200 molecules of putrescine, 100 molecules of spermidine, and 40 molecules of spermine which could neutralize 11% of the viral genome. the same polyamines are present in different proportions in the krebs ascites tumor cell in which the virus was grown. | 1980 | 6246257 |
| specificity of protein synthesis inhibitors in the inhibition of encephalomyocarditis virus replication. | effect of protein synthesis inhibitors on encephalomyocarditis virus production in l-cells was studied. inhibition of initiation by hypertonicity, harringtonine, or pactamycin decreased viral protein synthesis to a lesser extent than that of host. virus yield was unaffected or actually enhanced by low concentrations of these inhibitors. on the contrary, the elongation inhibitors cycloheximide, anisomycin, and emetine, shown previously to inhibit viral protein synthesis preferentially, had a grea ... | 1980 | 6246261 |
| encephalomyocarditis virus infection of cultured murine pancreatic beta-cells. | 1980 | 6246437 | |
| differential stimulation of capped mrna translation in vitro by cap binding protein. | 1980 | 6246452 | |
| anti-viral effects of single-stranded polynucleotides against avirulent semliki forest virus infection of mice and avirulent infection of rats with encephalomyocarditis virus. | single-stranded polynucleotide preparations, which neither induce detectable interferon nor affect immune responses, suppress development of antiviral antibodies in mice infected with an avirulent strain of sfv. on a weight basis the antiviral activity of a mixture of poly(i) and poly(ho5c)-copolymer is greater than that of trna and similar antiviral effects are observed against a related virulent strain of sfv. emc virus causes and avirulent infection of rats and development of emc virus antibo ... | 1980 | 6246856 |
| [role of insulitis and autoimmune component in the etiology of diabetes mellitus]. | 1980 | 6249250 | |
| antibiotics that specifically block translation in virus-infected cells. | several antibiotics including anthelmycin, blasticidin s, destomycin a, gougerotin, hygromycin b and edeine complex, known to powerfully block translation in cell-free systems, did neither inhibit protein synthesis in intact mouse l and 3t6 cells, nor in hamster bhk 21 cells, due to failure to cross the cell plasma membrane. however, after viral infection, these antibiotics exhibited a marked blockade of translation, that is related to the permeability changes induced by viral infection. the inh ... | 1980 | 6251018 |
| shutoff of hela cell protein synthesis by encephalomyocarditis virus and poliovirus: a comparative study. | previous experimental results have suggested that poliovirus and encephalomyocarditis (emc) virus employ very different mechanisms for shutting off host protein synthesis. however, this conclusion is suspect, inasmuch as different cell types were used for the two viruses; hence the apparent mechanistic differences might be specific for cell type and not virus type. to test this possibility we compared shutoff mechanisms in poliovirus- and emc virus-infected hela cells. striking differences were ... | 1980 | 6251263 |
| comparative effects of an inflammatory reaction on the resistance of mice to bacterial and viral infections. | the induction in mice of a sterile subcutaneous granuloma exerted no influence upon the mortality following their infection with herpes type 1, murine hepatitis or encephalomyocarditis viruses. attempts to reproduce the resistance -- which has been found to occur as a result of the granulomatous reaction, in the case of bacterial, fungal or protozoa infections and tumour invasions -- by varying the route and timing of the virus inoculation or the strain of mice have failed. we conclude that it i ... | 1980 | 6251747 |
| viral infection permeabilizes mammalian cells to protein toxins. | 1980 | 6251972 | |
| virus-induced diabetes mellitus. xviii. inhibition by a nondiabetogenic variant of encephalomyocarditis virus. | plaque purification of the m variant of encephalomyocarditis (emc) virus resulted in the isolation of two stable variants: one diabetogenic and designated d and the other nondiabetogenic and designated b. when the d variant was inoculated into sjl/j male mice, hypoinsulinemia and hyperglycemia developed in > 90% of the animals. in contrast, none of the mice inoculated with the b variant developed diabetes. histologic examination of pancreata from mice infected with the d variant revealed insulit ... | 1980 | 6252275 |
| [nature of a virus-specific protein detected in the composition of a ribonucleoprotein containing cellular messenger rna during viral infection]. | 1980 | 6252976 | |
| variations in the contribution of induced interferon and adjuvanticity to the antiviral effect of different polyinosinic acid . polycytidylic acid formulations in mice infected with encephalomyocarditis virus. | treatment of mice with polyinosinic acid . polycytidylic acid [poly(i) . poly(c)] 6 h before infection and once daily on days 1, 2, 3, 4, 7, and 10 after infection with encephalomyocarditis virus was found to confer no additional protection as compared with a single treatment 6 h before infection. when complexed with a colloid formed between carboxymethylcellulose and polylysine, poly(i) . poly(c) conferred significant additional protection with the multiple treatment regimen compared with a sin ... | 1980 | 6253403 |
| induction of diabetes by cumulative environmental insults from viruses and chemicals. | encephalomyocarditis virus (emc) induces diabetes in certain inbred strains of mice by infecting and destroying pancreatic beta cells, the severity of the diabetes depending on the number of beta cells destroyed. in strains of mice resistant to emc-induced diabetes, insufficient beta cells are damaged to alter glucose homeostasis. however, diabetes can be produced in many species by streptozotocin, a highly specific beta-cell toxin. here, we used concentrations of streptozotocin that did not pro ... | 1980 | 6253833 |
| the structure of the covalent linkage between proteins and rna in encephalomyocarditis virus. | two protein, vpga and vpgb, are covalently bound to the virion rna of encephalomyocarditis (emc) virus. their molecular weightrs, as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate are 10,000 and 8,000, respectively. a study of nucleotide-peptides isolated from vpg-rna compound has shown that vpga is bound to the 5'-terminal nucleotide of rna by a phosphodiester bond. the 5'-terminal nucleotide of rna is uridylic acid. it is the hydroxy group of the tyr ... | 1980 | 6253907 |
| receptors for encephalomyocarditis virus on murine and human cells. | 1980 | 6254250 | |
| a comparative study on the u.v. resistance of double-stranded and single-stranded encephalomyocarditis virus rnas: evaluation of the possible contribution of host-mediated repair. | to reveal previously suggested host-mediated repair of u.v.-induced lesions in dsrna of encephalomyocarditis (emc) virus, two sets of experiments have been carried out: (i) samples of dsrna of emc virus were irradiated with different doses of u.v. light and their infectivity was assayed in krebs ii cells, before and after conversion of dsrna into a ss form: (ii) samples of ssrna of ems virus were similarly irradiated and their infectivity was assayed before and after conversion of ssrna into a d ... | 1980 | 6255078 |
| picornaviral vpg sequences are contained in the replicase precursor. | it has previously been shown that the rna replicase of encephalomyocarditis virus contains two virus-coded proteins, d and e, which are produced in two successive proteolytic steps: (i) c leads to d + ?; and (ii) d leads to p22 + e. it is here shown (i) that virus protein h (molecular weight, 12,000) is the previously unidentified product of the first step and (ii) that vpg, a protein linked covalently to the virion rna, yields two tryptic peptides found in protein c but not in protein d. the re ... | 1980 | 6255181 |
| stimulation of encephalomyocarditis virus rna translation in wheat embryo extracts by rabbit reticulocyte ribosomal wash. | encephalomyocarditis virus rna induced a low level of amino acid incorporation in wheat embryo extracts, but the incorporation did not result in the formation of any viral proteins. however, if wheat embryo extracts were supplemented with a ribosomal wash fraction from rabbit reticulocytes, a large stimulation of amino acid incorporation and the formation of encephalomyocarditis virus-specific proteins were obtained. among the proteins synthesized were capsid precursor proteins which can be proc ... | 1980 | 6255195 |
| viral diabetes mellitus in man and experimental animals. | accumulating evidence strongly suggests that viruses may play an etiologic role in some cases of diabetes mellitus. the importance of environmental factors in the pathogenesis of the disease is suggested by genetic and epidemiological observations. group b coxsackie viruses and mumps virus have been implicated, and the evidence suggests that several other agents also could play a role in the disease. in experimental animals, a picornavirus similar to the coxsackie viruses exhibits specific tropi ... | 1981 | 6257111 |
| cross-linking of viral rna by 4'-aminomethyl-4,5',8-trimethylpsoralen in hela cells infected with encephalomyocarditis virus and the tsg114 mutant of vesicular stomatitis virus. | 1981 | 6258315 | |
| enhancement of encephalomyocarditis virus replication in l cells treated with insulin. | 1981 | 6259643 | |
| the growth of four human and animal enteroviruses in the central nervous systems of mice. | the pattern of cns infection of our enteroviruses, coxsackievirus a14, encephalomyocarditis (emc) virus, gdvii virus, and vilyuisk virus, was investigated. the regional sites of virus replication were correlated with pathological changes. these viruses were found to replicate and produce similar lesions in selected sites in the mouse cns during acute infection. virus antigen and histological lesions were essentially confined to the gray matter, with additional but less direct support for this be ... | 1981 | 6260909 |
| reversion by hypotonic medium of the shutoff of protein synthesis induced by encephalomyocarditis virus. | infection of human hela cells by picornaviruses produces a drastic inhibition of host protein synthesis. treatment of encephalomyocarditis virus-infected hela cells with hypotonic medium reversed this inhibition; no viral protein synthesis was detected. the blockade of viral translation by hypotonic conditions was observed for a wide range of multiplicities of infection. however, only with low virus-to-cell ratios did cellular protein synthesis resume. the ratio of cellular to viral mrna transla ... | 1981 | 6261005 |
| experimental models of juvenile onset (insulin-dependent) diabetes mellitus. | 1980 | 6261120 | |
| proteolytic activity of the nonstructural polypeptide p22 of encephalomyocarditis virus. | 1981 | 6261761 | |
| effect of genetic obesity in mice on the induction of diabetes by encephalomyocarditis virus. | the "m" variant of the encephalomyocarditis (emc) virus causes a diabetes-like disease in some, but not all, strains of mice. the genetic basis for either resistance or susceptibility to the diabetogenic effect of the virus is not known. after infection with emc, c57bl/6 mice seldom develop hyperglycemia and the insular lesions are subtle. to explore the possible effects of metabolic influences on the viral susceptibility of the islets, we studied c57bl/6 mice that were carriers of the ob gene. ... | 1981 | 6262170 |
| preparation of erythrocyte receptors for viruses by affinity chromatography. | a comparatively simple method for the purification of human erythrocyte receptors for encephalomyocarditis and influenza viruses is described. the procedure utilises the fact that these viruses share in common the erythrocyte receptor for wheat germ agglutinin (wga), which enables commercially available wga-sepharose to be used in the purification of receptors for these viruses by affinity chromatography. conditions are also described for introducing either 125i into the receptor in situ, or 3h- ... | 1980 | 6262336 |
| two-dimensional electrophoretic analysis of encephalomyocarditis viral proteins. | all four capsid proteins of encephalomyocarditis virus and the precursor to two of these were resolved from purified virions with two-dimensional gel electrophoresis. in addition, all of the known stable virus-specific proteins found in infected cells, but not the primary and intermediate precursor proteins, could be resolved with these techniques. | 1981 | 6262532 |
| encephalomyocarditis viral rna can be translated under conditions of poliovirus-induced translation shutoff in vivo. | superinfection with poliovirus of hela cells already infected with encephalomyocarditis (emc) virus does not inhibit translation of emc viral mrna, whereas residual host translation is completely inhibited. this result indicates that the cap recognition factors inactivated by poliovirus are not required for translation of emc viral mrna in vivo, in agreement with previous in vitro experiments. this raises the question of why emc virus has evolved a capindependent translation mechanism. | 1981 | 6264143 |
| [factor facilitating complete translation of the encephalomyocarditis virus genome]. | 1981 | 6265184 | |
| cell-produced viral inhibitor: possible mechanism of action and chemical composition. | a newly recognized cell-produced viral inhibitor appeared to be spontaneously released from most cells in tissue culture. it strongly inhibited the replication of a variety of viruses but did not exhibit species specificity as does interferon. these studies on the inhibitor's mechanism of action indicated that it inhibited attachment and penetration of virus by a readily reversible reaction requiring the presence of both virus and cells. studies of inactivation by specific enzymes or chemicals i ... | 1981 | 6265357 |