Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| synthesis and breakdown of pppa2'p5'a2'p5'a and transient inhibiton of protein synthesis in extracts from interferon-treated and control cells. | incubation of the mouse l-cell-free system with a concentration of pppa2'p5'a2'p5'a [(2'-5')an] just sufficient to inhibit protein synthesis results in formation of a high-molecular-weight, heatlabile inhibitor and enhanced ribonuclease activity and in the rapid breakdown of (2'-5')an to atp. the (2'-5')an-enhanced ribonuclease activity is also unstable and in the absence of a (2'-5')-an-regenerating system inhibiton of protein synthesis is transient. although interferon treatment enhances the s ... | 1978 | 216547 |
| virus-induced diabetes in mice: a quantitative evaluation of islet cell population by immunofluorescence technique. | the endocrine cell populations of pancreatic islets in encephalomyocarditis (emc)-virus infected mice were assessed quanititatively by immunofluorescence using specific antisera against 4 islet hormones. a marked reduction of the volume of insulin-containing (b-) cells (up to one tenth of control values) was observed at all stages studied in the hyperglycaemic mice. this was accompanied by the inversion of the normal ratio between b- and non b-cells. the volume of the latter cell types was also ... | 1978 | 216598 |
| effect of ammonium salts on the interferon-induced antiviral state in mouse l cells. | the addition of ammonium salts to cells treated with interferon prevents the development of the antiviral state and destroys it when already established. this treatment does not seem to act on the binding of interferon to the cells but blocks a further step of activation on the cell membrane. the anti-interferon effect of ammonium salts is reversible with a complete recovery of the antiviral state. it is postulated that these salts may stabilize the interferon-receptor complex and thus prevent t ... | 1978 | 217950 |
| heterospecific activity of rat interferon. | in the experiments performed in vitro and in vivo it has been found that the rat and rat embryo fibroblasts cultured in vitro after the induction with virus produce interferon which displays the antiviral activity not only in the homologous cells but also in the heterologous ones. when analysed by chromatography on sephadex g-100 it was shown that the rat serum contains two interferon populations differing in the molecular weight and both active in the homologous and heterologous cells. the inte ... | 1978 | 219806 |
| studies on the mode of action of ime--an inhibitor of interferon activity from mouse embryo tissues. | ime--inhibitor of interferon activity from mouse embryo tissues does not inactive interferon by direct contact; it does not inhibit the production of interferon and it does not affect the replication of challenge virus. ime shows no species-specific activity since it exhibits anti-interferon action not only in homologous interferon system but also in the heterologous rat, chick and human interferon systems. the interferon-induced antiviral state as well as the efficient cell's metabolism appear ... | 1978 | 219807 |
| the 3'-terminal nucleotide sequence of encephalomyocarditis virus rna. | poly(a)-containing encephalomyocarditis virus rna functions as an excellent template for cdna synthesis in vitro with an rna-dependent dna polymerase in the presence of an oligothymidylate primer. under appropriate conditions, discrete transcripts of increasing chain length were obtained, suitable for sequence analysis. a limited cdna fragment of 36 nucleotides, primer (dt)10 included, was synthesized when dgtp was omitted from the reaction mixture and its primary structure was elucidated using ... | 1978 | 74334 |
| rubella infection and diabetes mellitus. | the incidence of diabetes mellitus was increased in patients with congenital rubella. experimental congenital rubella infection in rabbits caused histological changes in the beta-cells of the pancreatic islets similar to those found in mice made diabetic by the m variant of the encephalomyocarditis virus. it is concluded that the diabetes seen in congenital rubella is due to viral infection of the pancreatic islet cells. | 1978 | 74564 |
| sequence of 129 nucleotides at the 3'-terminus of encephalomyocarditis virus rna. | the sequence of 129 nucleotides next to the poly(a) tail of encephalomyocarditis virus rna has been determined by rapid gel sequencing of cdna synthesized with dna polymerase i or reverse transcriptase and a phasing primer, [5'-32p]p(dt)8dc. the sequence is in accord with (a) the pyrimidine tracts which were mapped in blocks along the cdna, (b) the sequences of seven characteristic t1 rnase oligonucleotides in the rna transcribed from the cdna with rna polymerase, and (c) a limited amount of seq ... | 1978 | 79485 |
| 3'-terminal nucleotide sequence of encephalomyocarditis virus rna determined by reverse transcriptase and chain-terminating inhibitors. | we have adapted the chain-termination method for determining the nucleotide sequence of dna of sanger, nicklen, and coulson [(1977) proc. natl. acad. sci. usa 74, 5463--5467] for use with reverse transcriptase (rna-directed dna nucleotidyltransferase) on rna templates. with this method and using a primer (the octanucleotide pdt7rc) directed at the 3'-terminal poly(a), we have determined a sequence of 166 residues in the genomic rna of the picornavirus encephalomyocarditis virus. | 1978 | 81487 |
| the effect of inhibitors of cellular rna synthesis on stimulation of mouse encephalomyocarditis virus reproduction by poliovirus in hela and mio cells. | inoculation of hela and mio cells with a guanidine-dependent mutant of poliovirus (gd-polio) in the absence of guanidine resulted in stimulation of mouse encephalomyocarditis (emc) virus reproduction. no stimulation was found to occur in the presence of actinomycin d, on pre-treatment of the cells with cordycepin, or on their uv irradiation or enucleation. in contrast to hela cells, the enhancement of emc virus reproduction by gd-polio in mio cells required no current synthesis of cellular rnas: ... | 1978 | 27964 |
| poly (a) polymerase activity in l cells following encephalomyocarditis virus infection. | poly (a) polymerase activity has been measured in crude cytoplasmic extracts of mouse l cells infected with encephalomyocarditis (emc) virus. after infection there is first a decrease in enzyme activity followed by an increase which itself precedes detectable virus rna and protein synthesis. the activity of the enzyme then declines before the release of mature virions and cell death take place. the early inhibition of poly (a) polymerase activity is correlated with the virus-induced shut-off of ... | 1978 | 29079 |
| isolation of encephalomyocarditis virus from the pheasant (phasianus colchicus) in czechoslovakia. | the first isolation of encephalomyocarditis (emc) virus from the blood and brain of a pheasant (phasianus colchicus) captured in moravia is reported. complement-fixation (cf) tests with reference antisera revealed no relationship to any of a wide range of known arboviruses. | 1978 | 29473 |
| viral superinfection in cells carrying an arenavirus and/or a togavirus. | four lines of the same l-cell clone were transferred 60 times in parallel: uninfected cells, a line carrying lymphocytic choriomeningitis virus (lcmv), another one carrying tick-borne encephalitis virus (tev) and one carrying both viruses. in double persistency, lcm and tev were suppressed and stimulated, respectively. cell multiplication rates were comparable in all four lines. single lcmv persistence caused marked resistance of l cells to superinfecting viruses from various taxonomic groups, b ... | 1978 | 35946 |
| encephalomyocarditis virus rna. iii. presence of a genome-associated protein. | a low-molecular-weight protein was found to be associated with intact 35s rna isolated from purified encephalomyocarditis virus. this protein was positively charged at ph 3.5, sensitive to proteinase k treatment, and labeled with either 3h-amino acids or 32pi. | 1978 | 202751 |
| antiviral effect of 3-[bis-(2-hydroxyethyl)-amino]-acetophenone-[4,5-diphenyl-oxyazolyl-(2)]hydrazone (imet 98/69) in mice. | the potential in vivo antiviral activity of 3-[bis-(2-hydroxyethyl)-amino]-acetophenone-[4,5-diphenyl-oxazolyl-(2)]-hydrazone (imet 98/69) was evaluated on model infections in mice. animals treated subcutaneously (s.c.) with 1 mmole of the drug per kg body weight once daily for five days were significantly protected against a lethal infection with cardioviruses, semliki forest virus and vaccinia virus. in influenza a and b virus models no antiviral activity was observed either after s.c. or oral ... | 1979 | 44666 |
| inhibition of activity of encephalomyocarditis virus-induced rna polymerase by antibodies against cellular components. | 1979 | 85364 | |
| natural occurrence of 2-5a in interferon-treated emc virus-infected l cells. | until now the interferon-mediated 2'-5' adenine oligonucleotide inhibitors (2-5a) of cell-free protein synthesis have not been detected in intact cells. here we report their natural occurrence in interferon-treated, emc virus-infected mouse l cells in amounts consistent with the idea that they play a part in the inhibition of virus growth. | 1979 | 95208 |
| 2'5'oligo(a) polymerase activity and inhibition of viral rna synthesis in interferon-treated hela cells. | 1979 | 219884 | |
| [current knowledge in the field of insulin-dependent diabetes]. | 1979 | 220694 | |
| rat interferons. vi. heterologous interferon in the treatment of viral infections. | in previous studies in vitro we demonstrated the protection of mouse cells against viral infections by rat interferon. in continuation, the present paper reports results of a study designed to confirm this heterospecific activity of rat interferon in vivo. experiments were carried out with mice of the inbred 129/aoboy strain, inoculated intranasally or intraperitoneally with emc-strain col mm, vsv and influenza a 055/74 viruses, and treated with mouse or rat interferon administered by the same r ... | 1979 | 220932 |
| enhancement of infectivity of encephalomyocarditis virus rna by amphotericin b methyl ester. | the methyl ester of amphotericin b (ambme), a macrolide polyene antibiotic, enhanced the infectivity of encephalomyocarditis (emc) virus rna for l929 cells. ambme alone (100 microgram/ml) resulted in increases in emc virus rna infectivity of 10- to 100-fold. addition of deae dextran at concentrations (5 microgram/ml), which alone slightly suppressed emc virus rna infectivity, further augmented the effects of ambme (augmentation in infectivity up to 750-fold). ambme did not inhibit rnase, did not ... | 1979 | 217959 |
| comparative studies on the genomes of some picornaviruses: denaturation mapping of replicative form rna and electron microscopy of heteroduplex rna. | 1979 | 218342 | |
| selective inhibition of protein synthesis in virus-infected mammalian cells. | a number of translation inhibitors were tested for their effects on both control and encephalomyocarditis virus-infected mouse 3t6 cells. the virus-infected cells were specifically inhibited by gougerotin, edeine, and blasticidin s, whereas these drugs failed to penetrate into uninfected cells. inhibition of infected cells by gougerotin became apparent when the synthesis of viral proteins commenced, suggesting that the latter process is accompanied by a permeability change in the cells that allo ... | 1979 | 219211 |
| encephalomyocarditis virus-induced diabetes mellitus treated by islet transplantation. | there is considerable evidence that at least some cases of juvenile onset diabetes mellitus in humans are a result of viral infection. viral-induced diabetes in mice may provide an experimental counterpart more similar to the clinical situation than chemical-induced diabetes. our experiments in such mice indicate that islet transplantation is effective in ameliorating viral-induced diabetes and is encouraging for ultimate clinical application of islet transplantation to juvenile onset insulin-de ... | 1979 | 219567 |
| [melting and reassociation of double-stranded rna of the encephalomyocarditis virus]. | the processes of melting and reassociation of double-stranded rna in dimethylsulfoxide were studied. the addition of a small amount of licl results in great results in great reduction of tm (temperature of melting), whereas the nacl produces the opposite effect. it is suggested, that licl coordinates the molecules of h2o, reducing their activity, and consequently destabilises dsrna. mild conditions for melting and reassociation of rna can be created. it was found that under optimal conditions fo ... | 1979 | 217455 |
| [reproduction of murine encephalomyocarditis virus in enucleated krebs 2 ascitic carcinoma cells]. | enucleated cells of ascites carcinoma krebs 2 (cytoplasts) were prepared. the cells were centrifugated for this purpose in a discontinuous ficoll density gradient containing cytochalasine b. the cytoplasts formed turbid bands in phycol solution at the density of 1.037--1.053 g/ml. the cytoplasts failed to synthesize rna, but proteins were synthesized for several hours. encephalomyocarditis virus replicated in the ascites carcinoma cytoplasts, but its yield was 10 to 100-fold lower as compared to ... | 1979 | 217469 |
| sequence and location of the poly c tract in aphtho- and cardiovirus rna. | the poly c tract in the rna of the aphtho- and cardio viruses has been examined in several isolates of foot-and-mouth disease virus (fmdv) and encephalomyocarditis (emc) virus. the length of the tract is variable, containing 100 to 170 bases in the fmdv isolates and 80 to 250 bases in the emc virus isolates. each poly c tract contains c. 10% a and u residues, located at the 5' end, i.e. most of the tract is a continuous run of c residues. the position of the tract on the genome was the same in e ... | 1979 | 223128 |
| mechanism for discrimination between viral and host mrna in interferon-treated cells. | in extracts of interferon-treated hela cells, rna covalently linked to double-stranded rna (dsrna) is preferentially degraded compared with mrna not linked in dsrna. this was established by following the degradation of poly(a)-containing mrna annealed with poly(u), of poly(c)-containing encephalomyocarditis virus rna annealed with poly(i), and of the replicative intermediate of the virus isolated from infected cells. in extracts of interferon-treated cells, dsrna promotes the synthesis of a seri ... | 1979 | 223150 |
| successful islet transplantation in spontaneous diabetes. | optimism for islet transplantation is based on reversal of diabetes artificially induced in animals by pancreatectomy or beta cell toxins. in naturally occurring diabetes, implanted islets might be destroyed by the etiologic agent of the original disease; e.g., virus infection, genetic factors, or autoimmunity. genetically determined diabetes in obese mice, in fact, is resistant to islet transplantation. since these mice are hyperinsulinemic and not similar to human juvenile onset diabetes (jod) ... | 1979 | 223249 |
| biochemical and ultrastructural changes in a and b cells of the islets of langerhans of mice infected with emc virus. | 1979 | 223928 | |
| does insulin dependent diabetes mellitus have a viral etiology? | clinical, epidemiological, and experimental observations suggest that common viruses may play an etiologic role in at least some cases of insulin dependent diabetes mellitus. the evidence is summarized and critically assessed in this presentation. | 1979 | 223962 |
| effect of viruses on luminol-dependent chemiluminescence of human neutrophils. | the effects of newcastle disease, herpes simplex, vaccinia, encephalomyocarditis, vesicular stomatitis and reoviruses on in vitro function of neutrophils were studied in ficoll-hypaque-separated polymorphonuclear leukocytes (pmn) employing the technique of luminol-dependent chemiluminescence. newcastle disease, herpes simplex vaccinia, and reoviruses depressed chemiluminescence by 98, 65, 46, and 29%, respectively, while encephalomyocarditis and vesicular stomatitis viruses had no inhibitory eff ... | 1979 | 223982 |
| translation of encephalomyocarditis virus rna in reticulocyte lysates: kinetic analysis of the formation of virion proteins and a protein required for processing. | in cell-free extracts derived from rabbit reticulocytes, encephalomyocarditis rna can be translated completely, and the products can be processed extensively to give encephalomyocarditis virion proteins and several nonvirion proteins, including a genome-coded protein required for processing. the latter is probably a protease. translation is very efficient. under typical conditions, each emc rna is translated approximately eight times during a 3-h period. kinetic analyses (time-course experiments ... | 1979 | 224211 |
| [covalent bond between rna and protein in encephalomyocarditis virus]. | deproteinized encephalomyocarditis [32p]rna, after digestion with a mixture of rnases a, t1 and t2, yields mononucleotides and a labelled compound, which is positively charged at ph 3.5. this product can be digested with pronase and has a close electrophoretic mobility to a protein with a molecular weight of 7000-8000. covalently bound nucleotide-peptides were isolated from this compound after treatment with rnases and pronase. it was shown that the 5'-terminal uridylic acid is covalently linked ... | 1979 | 224308 |
| virus induced diabetes and the immune system. ii -- evidence for an immune pathogenesis of the acute phase of diabetes. | the infection of normal dba2 and balb/c nu/ + mice with 2 x 10(2,6) tcid50 of the m variant of the emc virus induced pathological mean glucose values of 426 +/- 99 mg/100 ml in dba2 mice and 292 +/- 130 mg/100 ml in balb/c nu/ + mice on day five following infection. as diabetic animals died afterwards, mean glucose values decreased in the surviving animals on day seven and fourteen. the infected immunodeficient balb/c nu/nu mice with thymus aplasia did not show abnormal mean glucose values or hi ... | 1979 | 224966 |
| [inhibition of formation of the preinitiator complex (ribosomal 40s subparticle met-trnametphi) in krebs ii cells infected with encephalomyocarditis virus]. | 1979 | 225152 | |
| the formation of complexes between polynucleotides, carboxymethylcellulose and polylysine which are anti-viral in mice without inducing interferon. | 1979 | 225654 | |
| effects of amphotericin b and its methyl ester on the antiviral activity of polyinosinic:polycytidylic acid. | since the macrolide polyene antibiotics, amphotericin b (amb) and its methyl ester (ambme), augment interferon production by polyriboinosinic:polyribocytidylic acid [poly(i):poly(c)] in vitro, experiments were undertaken to determine how amb and ambme affect the antiviral activity of poly(i):poly(c) and interferon. ambme increased the direct antiviral activity of poly(i):poly(c) 10(2)-to 10(4)-fold in l929, flow 6000, and t98g cells. viral replication, measured by either direct plaque formation ... | 1979 | 225986 |
| [low-molecular weight ribonucleic acid in the composition of virus-specific polysomes in cells infected with encephalomyocarditis virus]. | 1979 | 226184 | |
| activation of a nuclease by pppa2'p5'a2'p5'a in intact cells. | 1979 | 226408 | |
| altered immune reactivity in encephalomyocarditis-m variant (emc-m)-induced diabetes in mice. | approximately 50% of dba/2j male mice infected with emc-m develop glycosuria with suppressed immune responsiveness to the mitogens pha, con a and pwm. the greatest degree of suppression was noted with con a treated cultures. in vivo treatment with levamisole, a known t cell stimulant, especially increased the response to con a but exacerbated the diabetogenic state as reflected by increased occurrence of glycosuria. virus infected mice, given anti-lymphocyte serum (als), showed marked ameliorati ... | 1979 | 226473 |
| virus-induced diabetes mellitus: infection of mice with variants of encephalomyocarditis virus, coxsackievirus b4, and reovirus type 3. | 1979 | 227239 | |
| [initial stages of the interaction of murine interferon with l929 cells]. | after contact with mouse culture interferon in the cold, the resistance to viruses in l cells develops only after the cells are placed into a thermostate at 37 degrees c. the use of colcemide destroying microtubules prevents the development of this resistance at an early (actinomycin-sensitive) stage of interferon-cell interaction. in the actinomycin-resistant stage, however, colcemide practically exerts no influence on the interferon-induced resistance to viruses. | 1979 | 228496 |
| protease required for processing picornaviral coat protein resides in the viral replicase gene. | partial purification of the encephalomyocarditis protease synthesized in extracts from rabbit reticulocytes shows that the activity responsible for cleaving coat precursor protein cosediments with a previously unmapped virus-coded protein with an apparent molecular weight of 20,000. tryptic analysis shows that this protein is derived from protein d, a virus-coded component of the encephalomyocarditis rna polymerase. | 1979 | 229266 |
| determination of the length distribution of poly(a) at the 3' terminus of the virion rnas of emc virus, poliovirus, rhinovirus, rav-61 and cpmv and of mouse globin mrna. | rapid, detailed, and accurate analysis of the length spectrum of 3' terminal poly(a) in an rna population can be obtained by 3'-terminal 32p-labelling of rna with t4 rna ligase, digestion with ribonucleases t1 and a, and use of gel sequencing methods. length distributions of 3'-terminal poly(a) of emc virus, poliovirus, rhinovirus, rav-61, and cpmv virion rnas as well as mouse globin mrna are presented. | 1979 | 229465 |
| lead-cadmium interaction: effects on viral-induced mortality and tissue residues in mice. | simultaneous exposure to lead and cadmium is highly probable due to common environmental sources of exposure. mice were exposed simultaneously for 10 wek to lead and cadmium and effects were observed on accumulation of the metals in tissues and susceptibility to viral challenge. the incidence of viral-induced mortality was enhanced in all groups of mice exposed to lead and suppressed in groups of mice treated with cadmium. mice exposed to both lead and cadmium had mortality rates intermediate to ... | 1979 | 229776 |
| encephalomyocarditis virus-specific polypeptide p22 is involved in the processing of the viral precursor polypeptides. | 1979 | 230074 | |
| encephalomyocarditis virus-specific polypeptide p22 possessing a proteolytic activity: preliminary mapping on the viral genome. | 1979 | 230085 | |
| absence of significant antiviral effects of beta-gamma-methylene gtp on encephalomyocarditis virus infection of l cells and mice. | the protein synthesis inhibitor beta-gamma-methylene guanosine triphosphate (gpp-ch2p) is shown here to be ineffective as a 'leaky membrane' antiviral agent against encephalomyocarditis virus infection of l cells and mice. studies with gppch2p in encephalomyocarditis virus-infected l cells indicate that the cells only become permeable to the inhibitor late in infection because the compound significantly inhibits protein synthesis only when added at 4 h p.i. at this time 50 to 70% of the new infe ... | 1979 | 230305 |
| production of antiviral and migration inhibitory activities in the peritoneum of mice after inoculation with allogenic ehrlich ascites tumor cells. | peritoneal inoculation of ehrlich ascites cells into mice stimulates the appearance of migration inhibitory factor (mif) not only in the peritoneum but also in the circulation of mice. whereas the mif-activity in the peritoneum reached maximum at 6 days and disappeared within 17 days, the mif-activity of sera reached maximum levels at about 11 days after intraperitoneal inoculation of tumor cells (10(6) of eac per mouse). in addition, an antiviral activity of peritoneal exudates was observed in ... | 1979 | 230674 |
| experimental infection in pigs with encephalomyocarditis virus. | 1979 | 231750 | |
| effects of environmental contaminants on the immune system. | 1979 | 233061 | |
| the influence of the major histocompatibility complex (h-2) on experimental diabetes in mice. | mice with different histocompatibility loci on an identical background genome (congenic resistant lines of mice) were used to study the possible influence of the histocompatibility complex on experimental diabetes. the major histocompatibility complex (h-2) was not found to influence the diabetogenic effect of encephalomyocarditis (emc) virus. in contrast the glucose intolerance following heterologous and homologous immunization with pancreatic antigens appeared h-2 influenced. antibodies agains ... | 1979 | 215479 |
| reversal of encephalomyocarditis virus-induced diabetes mellitus by islet transplantation. | 1979 | 222018 | |
| interconversion of linear and circular forms of double-stranded rna of encephalomyocarditis virus. | 1979 | 222058 | |
| lesions induced by encephalomyocarditis virus and coxsackievirus b in newborn mice. | electron microscopic studies of various tissues from virus-infected newborn mice disclosed a consistent form of viral cytonecrotic ultrastructural lesion in divergent types of cells (myocardial, valvular fibroblastic, aortic, exocrine and endocrine pancreatic, and hepatic cells) due to three different picornaviruses (coxsackieviruses b4 and b1 and encephalomyocarditis virus). the lesion is characterized by numerous membrane-vesicle complexes, margination of nuclear chromatin or nuclear pyknosis, ... | 1979 | 222229 |
| [the 5'-terminal sequence of encephalomyocarditis virus rna: localization of the poly c tract and its role in translation]. | 1979 | 222563 | |
| eukaryotic mrna cap binding protein: purification by affinity chromatography on sepharose-coupled m7gdp. | a 24,000-dalton polypeptide that binds strongly and can be specifically crosslinked to the 5'-terminal cap structure m7gpppn in eukaryotic mrnas has been detected in protein synthesis initiation factor preparations [proc. natl. acad. sci. usa (1978) 75, 4843--4847]. this polypeptide has been purified to apparent homogeneity by one chromatographic passage through an affinity resin prepared by coupling the levulinic acid o2',3'-acetal of m7gdp to ah-sepharose 4b. translation, in hela cell extracts ... | 1979 | 291969 |
| [viral etiology of insulin-dependent diabetes (author's transl)]. | data are collected here that may support the hypothesis that there is an infectious component in the genesis of insulin-dependent diabetes mellitus. the clinical and experimental data on which that hypothesis is based referring to viruses such as: mumps virus, rubella virus, encephalomyocarditis virus, and coxsackie b viruses, are presented. the authors mention the pathogenic mechanism, which extends over the existence of diabetogenic genes linked to the major complex of the histocompatibility h ... | 1979 | 459606 |
| 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 |
| a highly efficient method of cell infection with encephalomyocarditis virus rna. | a method for infecting krebs-ii cells with encephalomyocarditis virus rna based on treatment of the cells with deae-dextran at high concentration was elaborated. the specific infectivity of virion rna was 3 x 10(8) plaque-forming units per microgram, i. e. comparable to the specific infectivity of the whole virus. a high proportion of the cell population could be infected by this method. | 1980 | 6106373 |
| type i and type ii interferons: differential antiviral actions in transformed cells. | in transformed mouse embryo cells, type ii interferon had much less antiviral activity than type i interferon. in non-transformed cells, the two interferons had similar high activity, reversal of the phenotype of moloney sarcoma virus (msv) transformed cells by sodium butyrate restored their sensitivity to the antiviral action of type ii interferon. additional evidence for a role of the cytoskeletal network in the action of type ii interferon is that its antiviral effect is reduced by cytochalas ... | 1980 | 6155431 |
| on the mechanism of single-stranded rna synthesis by encephalomyocarditis virus replication complexes: preferential inhibition by adenylyl (beta, gamma-methylene)-diphosphonate. | 1980 | 6156090 | |
| 2'5' oligo(a) polymerase activity in serum of mice infected with emc virus or treated with interferon. | interferon-treated cells show an increase in two double-stranded rna (dsrna)-dependent enzymatic activities involving an oligoadenylate polymerase and a protein kinase (ref. 1 and refs therein). the polymerase converts atp into a series of oligonucleotides characterized by 2'5'-phosphodiester bonds, designated 2'5'-oligo(a) or 2-5a (ref. 1). these oligonucleotides activate an endoribonuclease that degrades rna in extracts of control and interferon-treated cells. these observations have been made ... | 1980 | 6157092 |
| [antiviral activity of murine interferons produced by bacterial and animal cell translation of messenger rna]. | interferon was produced by e. coli bacteria and animal cell messenger-rna--interferon translation (mrna--if). the activity of the interferon produced by simultaneous mrna--if translation in these two cellular systems was, approximately, similar. the interferons translated by bacteria and animal cells inhibited the cytopathic effect, reproduction and plaque-formation of vesicular stomatitis virus, and, to a greater extent, of mouse encephalomyocarditis virus. the virus titration was carried out b ... | 1980 | 6158177 |
| emulsifiers that enhance susceptibility to virus infection: increased virus penetration and reduced interferon response. | an emulsifier which had an environmental relationship to reye's syndrome, when used to treated l-929 cultures, was shown to increase the rate of encephalomyocarditis virus penetration and uncoating while having no effect on the attachment of virus or on the replication of infectious ribonucleic acid. this treatment also rendered l-929 cells unable to respond normally to interferon inducers and reversed an already established interferon antiviral state. it is proposed that one or more of these ac ... | 1980 | 6158915 |
| human leukocyte interferon produced by e. coli is biologically active. | a human leukocyte interferon cdna was enzymatically synthesized, inserted into the vector pbr322, and cloned in escherichia coli. the dna sequence codes for a 23-amino acid signal peptide followed by an interferon polypeptide of 165 amino acids. an expression plasmid was constructed which permits the synthesis in e. coli of 2.5 x 10(8) units of interferon per litre of culture. this leif protected squirrel monkeys from lethal encephalomyocarditis virus infection. | 1980 | 6159538 |
| 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 |
| experimental models of juvenile onset (insulin-dependent) diabetes mellitus. | 1980 | 6261120 | |
| 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 |
| enzyme-linked immunosorbent assay for immunoglobulin g antibody to encephalomyocarditis virus. | an enzyme-linked immunosorbent assay for immunoglobulin g antibody to encephalomyocarditis virus was developed. this assay was comparable to antibody assay by neutralization. its adaptability should be useful for laboratory and epidemiological studies of infections due to encephalomyocarditis virus. | 1980 | 6268654 |
| 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 |