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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.197829473
virus susceptibility of mouse hemopoietic cells in vitro: inhibition of granulocyte-macrophage precursor cells by newcastle disease virus.normal mouse bone marrow cells were exposed to encephalomyocarditis virus (emc), reovirus type 3 (reo3), influenza virus (flu), and newcastle disease virus (ndv) then assayed for granulocyte-macrophage precursor cells by the technique of colony formation in agar. exposure to emc, reo3, and flu caused a slight but variable loss of colony-forming potential, whereas exposure to ndv caused a very marked loss. ndv acted directly on the cells, not indirectly through release of colony-inhibiting factor ...1975163791
testicular atrophy in columbian black-tailed deer in california.during an 18-year period, 4.1% (34/831) of male deer (odocoileus hemionus columbianus) killed on a field station during the autumn hunting season had velvet-covered, often misshapen antlers, and at least two deer had testicular atrophy (gonads from most deer were not available for examination). testes from six similarly affected deer and several normal deer were compared histologically. lesions ranged from hypocellularity of the semeniferous tubules and relative hyperplasia or degeneration of in ...1975163381
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.197995208
characterization of the sequence next to the 3-terminal poly-(a) of encephalomyocarditis virus rna [proceedings]. 197768742
structural features of encephalomyocarditis virus rna from analysis of reverse transcription products.the presence in encephalomyocarditis (emc) virus rna of homonucleotide tracts 10 nucleotides or more in length has been investigated by testing the ability of homo-oligodeoxynucleotides to prime dna synthesis in the reverse transcriptase from avian myeloblastosis virus. neither (dc)10 nor (da)10 promoted incorporation of [3h]deoxynucleotides into acid-insoluble material but (dg)10 and (dt)12-18 were effective primers and produced dna products approximately 2000 nucleotides in length. we conclude ...197662663
use of polyethylene glycol-treated calf serum for cell cultures in virus and interferon studies.immunoglobulins and lipoproteins can be efficiently removed from calf serum by precipitation with polyethylene glycol (peg) 6000 under sterile conditions. the peg-treated serum is suitable for cell cultures used for virus growth and assays. moreover, peg was found to slow down the growth of l cells and to enhance the production and activity of mouse interferon.197550724
the neuraminidase yield-reduction bioassay of human other interferons.the production of neuraminidase by the recombinant influenza virus x7(f1) in human monkey, rabbit, hamster, mouse, and chicken cell cultures is inhibited by interferon. described is a new enzyme assay for neuraminidase that can be applied to the bioassay of interferons. the advantages of this interferon bioassay are its sensitivity, reproducibility, rapidity, and convenience.197550598
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 ...197829079
the direct anti-viral activity of single stranded polyribonucleotides. ii. the effect of molecular size and the involvement of cellular receptors. 197721398
the direct anti-viral activity of single stranded polyribonucleotides. i. potentiation of activity by mixtures of polymers which do not anneal. 197721397
some biological activities of rabbit anti-interferon serum.after prolonged immunization of rabbits with a semipurified mouse interferon preparation in freund's incomplete or al-span-oil adjuvant, a specific interferon-neutralizing immunoglobulin was obtained from antiserum with a capacity of neutralizing about 49000 mouse interferon units per ml. the specific activity of the antiserum and immunoglobulin was confirmed in tests in which the interaction of antibodies with the cell surface was ruled out. the antiserum (and the immunoglobulin) neutralized bo ...19765864
isolation and properties of the replicase of encephalomyocarditis virus.the rna-dependent rna polymerase (replicase) of encephalomyocarditis (emc) virus was found to be closely associated with the smooth membranes of infected bhk-21 cells. an rna-dependent emc replicase was extracted from the membranes with 0.15% sodium dodecyl sulfate (sds) and 1,1,2-trichlorotri-fluoroethane (genetron 113) and further purified by high-salt dextran-polyethylene glycol phase separation, sievorptive chromatography, and glycerol gradient sedimentation. the enzyme does not manifest str ...19765614
inactivation of viruses and bacteria by ozone, with and without sonication.selected organisms with public health significance were placed in a reaction chamber for treatment by ozonation, by ozonation and sonication, by sonication, or by sonication during oxygenation. vesicular stomatitis virus, encephalomyocarditis virus, gdvii virus, staphylococcus aureus, pseudomonas fluorescens, salmonella typhimurium, enteropathogenic escherichia coli, vibrio cholerae, and shigella flexneri were inactivated by treatment with ozone. when microorganisms were suspended in phosphate-b ...1975163616
the sick-sinus syndrome in africans.fifteen cases of the sick-sinus syndrome in young negroes are presented. the etiology was unknown in all cases; organic heart disease was absent. the very high default rate suggests that the prognosis may be grave. this disorder is by no means uncommon in young persons in tropical countries and the dangers of a mistaken diagnosis of epilepsy or a psychiatric illness have been emphasized. in the absence of an artificial pacemaker, it is suggested that sympathomimetic drugs, while not affecting th ...1975163570
the role of viruses in the pathogenesis of pancreatic disease and diabetes mellitus. 1975164049
inhibition of activity of encephalomyocarditis virus-induced rna polymerase by antibodies against cellular components. 197985364
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.197881487
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 ...197879485
animal model of human disease: diabetes mellitus (juvenile- and maturity- onset types). 1975164124
enhancement of antiviral protection against encephalomyocarditis virus by a combination of isoprinosine and interferon.the antiviral effect of interferon against encephalomyocarditis (emc) virus infection in mice was enhanced by isoprinosine. however, the enhancement was only obtained when both interferon and the virus were inoculated into the peritoneum; the inoculation route of isoprinosone did not modify significantly the final results. in addition, the time sequence of injections was of great importance; generally the injection of isoprinosine had to precede that of interferon by a few hours.197774245
[characteristics of encephalomyocarditis virus isolated from sick monkeys].a cytopathic filterable agent designated emc-70 was isolated in 1970 from macaca rhesus monkeys with encephalomyocarditis. its biologic and physico-chemical properties were studied. a number of primary and continuous cell cultures were found to be susceptible to the virus, and it was pathogenic for monkeys and small laboratory animals but did not multiply in chick embryos. the virus was stable to chlorofrom, thermolabile, stable to acids, and agglutinated group o erythrocytes of man, sheep, guin ...197664027
[persistence of latex agglutination inhibition antibodies in rabbits following application of poliomyelitis-, coxsackie-, echo- and encephalomyocarditis viruses. brief report]. 1975164163
a transfer rna-dependent protein synthesizing system from ehrlich ascites extracts.an homologous cell-free system from ehrlich ascites cells was made trna dependent by passing both the ribosomes and the ammonium sulfate fraction through deae-cellulose columns in 0.30 m kcl. protein synthesis was routinely stimulated 20-50 fold by the addition of 100 mug/ml of ascites cell trna in the presence of oviduct mrna, ascites mrna, or encephalomyocarditis rna.1975164951
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 ...197874334
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 ...197944666
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.197874564
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: ...197827964
virus-induced diabetes mellitus. iii. influence of the sex and strain of the host.nineteen inbred strains of male mice were infected with encephalomyocarditis virus. five strains became hyperglycemic and had abnormal values in glucose tolerance tests; three strains remained normoglycemic but had abnormal values in glucose tolerance tests; and the remaining strains showed no abnormalities in blood glucose levels or glucose tolerance tests. female mice from three of five strains tested also developed hyperglycemia, but in one strain (dba/2) the hyperglycemia was less severe in ...1975163872
the determination of secondary structure in the poly(c) tract of encephalomyocarditis virus rna with sodium bisulphite.the degree of secondary structure in the poly(c) tract of encephalomyocarditis virus (emcv) rna has been investigated using sodium bisulphite, which brings about the hydrolysis of non-base-paired cytidylic acid to uridylic acid in rna. the percentage conversion of c to u in the poly(c) region of native emcv rna was similar to that found in a synthetic polynucleotide lacking secondary structure [poly(c)]. when poly(i) was annealed to either native or denatured emcv rna, it protected the poly(c) t ...1975167355
[stimulation by isoprinosine of the antiviral effect of interferon].with a single dose of interferon, isoprinosine greatly enhances the antiviral protection of mice against the lethal effect of encephalomyocarditis virus (100 ld 50).197766996
factors in the inactivation of encephalomyocarditis virus in aerosols.encephalomyocarditis virus in aerosols is inactivated rapidly at relative humidities below 50%. in glycerol-water mixtures a similar decrease of infectivity occurs when the glycerol concentration exceeds 78% (wt/wt), corresponding to a relative humidity of 50%. the decay in aerosols does not involve oxygen or surface-dependent factors. variation of temperature shows the inactivation to be a low-energy process with an activation enthalpy of 15 kcal per mol. the damage could be ascribed to dehydra ...1975166928
evidence for the existence of protomers in the assembly of encephalomyocarditis virus.two capsid precursor subunits, which sediment on glycerol gradients at 13s and 14s, respectively, have been identified in cytoplasmic extracts of encephalomyocarditis virus-infected hela cells. the 13s subunit, which was detected after a 10-min pulse label with -3h-labeled amino acids, contained only capsid precursor chain a (mol wt 100,000). when the 10-min pulse label in such cells was chased for 20 min, the a-containing 13s subunit in the cytoplasmic extracts was replaced by a 14s subunit con ...1975167183
identification of a viral protein involved in post-translational maturation of the encephalomyocarditis virus capsid precursor.translation of encephalomyocarditis virus rna in a cell-free system from uninfected krebs ascites cells results in the synthesis of a major polypeptide product with a molecular weight of approximately 112,000. in contrast, when the viral rna is translated in a cell-free system from virus-infected cells, this polypeptide is absent and the largest polypeptide produced has a molecular weight of about 100,000. this latter polypeptide comigrates on sodium dodecyl sulfate-gels with in vivo virus capsi ...1975163926
glucose tolerance and pancreatic ultrastructure in mice with long-term diabetes induced by emc virus (m variant) (38518).of 27 young male cd-1 mice infected with the m variant of the encephalomycarditis (emc) virus and surviving for 11 or 12 mo, all but three had normal glucose tolerance curves, and all displayed normal islet cell morphology, at the time of sacrifice, in spite of an initital hyperglycemic response. three animals maintained diabetic glucose tolerance curves one year after infection but they, too, failed to show significant morphological alterations in their pancreatic beta cells.1975165527
antiviral-anticancer activity of tobacco leaf and the smoke condensate. 1975170632
in vitro translation of natural mrnas in a cell-free system containing components from interferon-treated chicken fibroblasts and factor preparations from mouse ascites cells or rabbit reticulocytes.the effect of interferon has been studied in a mixed cell-free protein synthesizing system. hemoglobin (hb) and encephalomyocarditis virus (emc)-rna can be efficiently translated in vitro in a system containing s-30 lysates or run-off ribosomes from primary chick embryo fibroblasts (cef) and a postmicrosomal supernatant from mouse ascites cells or a ribosomal-wash preparation from rabbit reticulocytes. ribosomes prepared from cef pretreated with high doses of homologous interferon (500 units/ml) ...1975170753
ultrastructural alterations of tissue cultures from human fetal brain infected with the e variant of emc virus.explant outgrowths from human fetal brain were infected with 104 plaque forming units of the e variant of the encephalomyocarditis virus. ultrastructurally, the majority of the cultured cells were astrocytes containing a moderate amount of glial fibrils. the earliest alterations at 44 hrs after infection of the culture consisted of dilatation of the rough endoplasmic reticulum (er) and moderate enlargement of the mitochondria with increased density of their matrix. twenty hours thereafter, incre ...1975170775
emc virus and cultured human fetal pancreatic cells. ultrastructural observations.tissue cultures of pancreatic acinar cells of seven human fetuses were infected with either the m or the e variant of the encephalomyocarditis (emc) virus. between the third and fifth days after infection, severe ultrastructural damage was noted. margination, condensation, and fragmentation of the nuclear chromatin and the appearance of numerous cytoplasmic vesicles filled with finely granular material were the major changes observed. viral particles were not identified. one hundred plaque-formi ...1975167704
demyelination and cytopathic effects in cultures of mammalian dorsal root ganglia infected with encephalomyocarditis virus.replication of encephalomyocarditis virus and its cytopathic effects were studied in myelinated cultures of dorsal root ganglia obtained from newborn mice. six hours after infection virus progeny was detected in the culture. at 24 h the virus titer reached 2 times 10(6) pfu per culture and remained at this level until 48 h. the first cytopathic alterations began at 24 h and consisted of rounding of schwann and satellites cells and their detachment from neurons. later, bead-like swellings of the ...1975168407
non-random frequencies of short oligonucleotide sequences within poliomyelitis and encephalomyocarditis virus rnas.in poliomyelitis and encephalomyocarditis virus rnas the relative frequencies of several short oligonucleotide sequences differ substantially from those expected on a random basis. the frequencies of cpgp-containing sequences are low, and the frequency of gpupapgp is considerably lower than that of gpapupgp. the relationship of these findings to those obtained from host cell rnas is descussed.1975168559
encephalomyocarditis (emc) virus infection of the femoral vein of newborn mice.the emc virus was found to infect and injure the femoral veins of newborn mice. emc viral crystals were found in the advential fibroblasts of these veins. in view of the extensive damage observed in the extremely small amount of tissue examined electron microscopically, the extent of the viral phlebitis must have been considerable. the relationship of these findings to the pathogenesis of thrombophlebitis in man provokes interesting speculations.1975169683
methylmercury: effect on oncogenic and nononcogenic viruses in mice.mice fed methylmercury chloride at dosages of 1 or 10 ppm for 84 days had significantly higher mortality rates when inoculated with encephalomyocarditis virus (nononcogenic) than did nonmethylmercury-treated mice. however, methylmercury fed to mice which were inoculated with rauscher leukemia virus (oncogenic) did not alter the course of neoplasia. these results demonstrate that prolonged exposure to subclinical concentrations of methylmercury increased susceptibility of a host to a nononcogenic ...1975171982
anti-viral activity of single-stranded homopolynucleotides against encephalomyocarditis virus and semliki forest virus in adult mice without interferon induction.single administrations of poly c or poly i are anti-viral against infections of encephalomyocarditis (emc) and semliki forest virus (sfv) in mice but poly u and poly a are not. the degree of protection is dose-dependent and mice which die do so at a later time when untreated controls even in a strain of mouse in which the time of death is not dependent on the dose of virus given. no circulating interferon is found after treating mice with poly c or poly i even at polynucleotide doses which give ...1976173799
early alteration of poliovirus in infected cells and its specific inhibition.hela cells infected with radioactive poliovirus type 2 were disrupted with ultrasonic treatment, followed by addition of a non-ionic detergent. two types of virus particles were found to sediment at 80 to 90% the rate of native virus. the first of these appeared to be a complex of native virus particles and membrane components, since treatment with 0-2% sds released infectious native particles. the second was non-infectious and its sedimentation rate was not greatly altered by sds. one hour afte ...1975167116
chromatographic studies on picornavirus capsid polypeptides.the polypeptides of encephalomyocarditis, mouse-elberfeld and type 5 rhinoviruses behave similarly when chromatographed on calcium phosphate (brushite), each being eluted by a linear phosphate buffer gradient containing sodium dodecyl sulphate in three major peaks, ci, c2 and c3. analysis of the peaks by polyacrylamide gel electrophoresis suggests that the major capsid polypeptides of these three picornaviruses elute in the order: delta (peak ci), gamma with (peak c2) and alpha (peak c3).1975167119
interferon treatment of ehrlich ascites tumor cells: effects on exogenous mrna translation and trna inactivation in the cell extract.we reported earlier that in cell extracts that were prepared from interferon-treated ehrlich ascites tumor cells and preincubated and passed through sephadex g-25 (s60int), the translation of exogenous mrna (viral and host) was impaired and the impairment could be overcome to a large extent by adding a crude trna preparation from ehrlich ascites tumor cells but not from escherichia coli. we find now that the rate of inactivation of some trna's (especially those specific for leucine, lysine, and ...1975173882
l-arginine elution of measles virus adsorbed on monkey erythrocytes.l-arginine (1 m) eluted measles virus adsorbed on monkey erythrocytes without affecting the infectious and hemagglutinating activities of the virus. this phenomenon was also observed for encephalomyocarditis virus and newcastle disease virus.1975166920
virus-induced diabetes mellitus. v. biological differences between the m variant and other strains of encephalomyocarditis virus.the m variant of encephalomyocarditis virus is very closely related serologically to five other strains of encephalomyocarditis virus. despite the serological relationship, these five viruses differ markedly from the m variant in their tissue tropisms and only the m variant infects beta cells of the pancreas, producing diabetes.1975172456
wildlife and environmental health: raccoons as indicators of zoonoses and pollutants in southeastern united states.inasmuch as terrestrial fauna are an integral part of our natural environment and are directly exposed to disease and pollutants, it follows that certain wild populations could serve to detect subtle alterations within ecosystems. a collection of studies on raccoons is presented to stimulate other researchers to develop the potential of our wildlife resources as monitors of environmental health. raccoons have been used as serologic sentinels for st louis encephalitis and venezuelan equine enceph ...1975170239
[functional activity of information rna isolated from krebs-ii cells infected with encephalomyocarditis viruses]. 1975172304
enhancement of immunity against murine syngeneic tumors by a fraction extracted from non-pathogenic mycobacteria.the data reported here demonstrate that a preparation extracted from nonpathogenic mycobacteria such as mycobacterium smegmatis and hereafter referred to as interphase material protected mice against ehrlich ascitic carcinoma, l-1210 leukemia, and another syngeneic lymphoid leukemia. furthermore, mice treated by this preparation were much less susceptible to endotoxins than when stimulated by bcg (bacillus calmette-guerin) or m. smegmatis cells. moreover, guinea pigs treated by interphase materi ...1975171670
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 ...197835946
failure of globin mrna to stimulate globin synthesis in cell-free extracts of interferon-treated globin-synthesizing mouse erythroleukemic cells. 1976174296
ultrastructural myocardial changes produced by viruses.some of the ultrastructural pathological alterations in the myocardium produced by viral infections with members of the picornavirus group are described. these alterations varied from mild to severe, with necrosis. in animals infected with coxsackie b1 virus and emc virus, readily identifiable viral crystals were frequently found in association with the myocardial lesions by means of electron microscopy. the electron microscope made it possible to study vary early myocardial changes which were n ...1975172990
in vitro translation of encephalomyocarditis viral rna: synthesis of capsid precursor-like polypeptides. 1976178097
virus-induced damage of the myocardial cell.a total of 330 male 3-week-old mice of the n.m.r.i./han. strain were infected with the m-variant of the emc (encephalomyocarditis) virus by subcutaneous inoculation of 0.25 ml of the virus suspension diluted 1:500. animals were killed at 4- or 6-hour intervals, respectively, and groups of 2 to 8 hearts were taken for virological, morphological, and biochemical studies. before the 8th hour after the inoculation, no virus and no pathological cell changes could be detected in the hearts; it is assu ...1975172991
preparation and characterization of eukaryotic initiation factor eif-3. formation of binary (eif-3-met-trnaf) and ternary (eif-3-met-trnaf-gtp) complexes.the 133,000 x g supernatant fraction prepared from ascites cells in 20 mm kcl (low ckl supernatant) contained the initiation factors eif-1 and eif-2 (and the elongation factore ef-1 and ef-2) but lacked eif-3; thus, low kcl supernatant could be used to assay for eif-3. eif-3 was prepared from a crude initiation factor perparation (a 250 mm kcl extract of ascites cell ribosomes precipitated with 70% saturated ammonium sulfate) by chromatography on deae-sephadex a-50 and hydroxylapatite. the eif-o ...1976178648
persistent reovirus infection of cho cells resulting in virus resistance.we obtained a persistently infected line of chinese hamster ovary cells by selection for resistance to reovirus infection. the cells were persistently infected by a population of viruses that were (i) cytopathic for parental chinese hamster ovary cells and (ii) similar to wild-type reovirus in molecular characteristics. the growth rate, plating efficiency, and morphology of the cells were altered. a large majority of the cells in the population were infected. there was no detectable interferon p ...1976176428
the selection of virus-resistant chinese hamster ovary cells.we have selected chinese hamster ovary (cho) cells resistant to infection by encephalomycarditis (emc) virus. thus far, we have obtained five lines resistant to emc, all of which manifest different phenotypes. three of the five are not persistently infected with virus, while two lines produce infectious virus and grow in its presence. the nonpersistently infected lines exhibit different resistance profiles to the other viruses we have tested, and they are stable in nonselective growth conditions ...1976182382
virus-induced diabetes mellitus. vi. genetically determined host differences in the replicating of encephalomyocarditis virus in pancreatic beta cells.beta cells were isolated from strains of mice that were susceptible and resistant to encephalomyocarditis (emc) viral-induced diabetes mellitus. beta cells from susceptible mice that were infected in vivo with emc virus showed higher viral titers, more severe degranulation, and lower concentrations of immunoreactive insulin than beta cells from resistant mice. immunofluorescence and infectious center assays revealed that pancreas from susceptible mice contained at least 10 times more infected ce ...1976177713
effect of ammonium 5-tungsto-2-antimoniate on encephalomyocarditis and vesicular stomatitis virus infections in mice.ammonium 5-tungsto-2-antimoniate (hpa 23) protected micr partially or completely against two strains of encephalomyocarditis (emc) virus and one strain of vesicular stomatitis (vsv) virus. the best protective effect was obtained with emc strain vr 129 and vsv when a single i.p. injection of hpa 23 was administered shortly before virus inoculation. mice protected by hpa 23 against emc strain vr129 had virus titres in the blood and brain similar to those in untreated mice. a synergism between inte ...1976177729
encephalomyocarditis virus infection of pigs. 1. an outbreak in new south wales.substantial pig mortalities due to heart disease caused by emc virus infection are described. the majority occurred in 1970 in conjunction with a rodent plague, but retrospective diagnosis of occasional similar mortalities in previous years was possible. mortality rates in pigs aged 3 to 16 weeks ranged from a few percent to over 50% and the rate was generally highest in younger animals. it is likely that a considerable proportion of cases was sub-clinical. focal or diffuse pale areas occurred i ...1975173273
encephalomyocarditis virus infection of pigs. 2. experimental disease.encephalomycarditis virus recovered from a pig mortality in new south wales was used to produce experimental infections. of 34 pigs exposed, 17 died and a further 7 were found to have severe heart lesions when killed. deaths occurred from 2 to 11 days after exposure with a mode of approximately 3 days. ten of 11 pigs exposed by intramuscular injection died and the remaining pig was killed after 28 days and found to have severe resolving heart lesions. of 15 pigs exposed per os to various doses o ...1975173274
[proceedings: immunologic demonstration of b and a cells in the pancreas of the dba-mouse during emc-virus infection]. 1975175611
[formation and persistence of latex-agglutination-inhibiting igg- and igm-antibodies in rabbits inoculated with poliomyelitis, coxsackie and encephalomyocarditis viruses (author's transl)].the formation and presistence of virus specific igg- and igm-antibodies produced in rabbits after a single dose of poliomyelitisvirus, coxsackievirus or encephalomyocarditisvirus were tested comparatively by latex-agglutination-inhibition test, hemagglutination-inhibition test and neutralization test. the animals were immunized either intravenously alone or with freund's complete adjuvant. the igm-antibodies were only detectable for a short time by the three tests. in the igg-fraction and in the ...1975175613
virus-induced diabetes mellitus. iv. genetic and environmental factors influencing the development of diabetes after infection with the m variant of encephalomyocarditis virus.the m variant of encephalomyocarditis virus (emc) infects pancreatic beta cells and causes the development of a diabetic syndrome in susceptible strains of mice. by examining four f1 crosses of susceptible and resistant strains of mice, we found that the development of diabetes after infection was inherited as a recessive trait. analysis of the data from the f2 generation indicated that more than one gene was involved in the development of emc-diabetes. the severity and frequency of abnormal glu ...1976176076
a study on the infectivity of encephalomyocarditis virus double-stranded rna with selectively inactivated strands. 1976183367
the inability of a diabetogenic virus to induce diabetes mellitus in athymic (nude) mice.the effect of a known diabetogenic m-strain encephalomyocarditis (emc)-virus in athymic nude mice (lacking the thymus-dependent lymphocyte system), and in heteroxygous littermates and homozygous normal mice of the background strain (c57/b16) was investigated. while by 3 weeks 4 out of 4 surviving virus-inoculated littermates and 9 out of 9 inoculated normal mice developed diabetes mellitus, none of the 7 surviving virus-inoculated nude mice became diabetic. virus was isolated from all inoculated ...1976183460
[localization of the polycytidylic sequence in the virion rna molecule of the encephalomyocarditis virus]. 1976181231
hydrosoluble immunostimulants of bacterial and synthetic origins.the role of whole mycobacteria, mycobacterial cell walls and waxes d as immunostimulants was well established many years ago. more recently three different research groups have shown that hydrosoluble components from mycobacterial and other bacterial origins were as active as waxes d or cell walls and were free of many side-effects. studies concerning the relationship between structure and activity were achieved which led to the description of a small biologically active fragment and to a first ...1976181265
poly(c) sequence is located near the 5'-end of encephalomyocarditis virus rna. 1976183773
limitation of reticulocyte transfer rna in the translation of heterologous messenger rnas.the effect of various trnas on protein synthesis was investigated using a trna-dependent cell-free system from ehrlich ascites cells. ascites cell trna and rabbit liver trna were found to promote efficient translation of globin mrna, oviduct mrna, and encephalomycarditis (emc) viral rna. in contrast, reticulocyte trna participated efficiently only in the translation of globin mrna; the translation of oviduct mrna and emc viral rna in the presence of reticulocyte trna resulted in the synthesis o ...1976183813
interactions between 125-i-labelled rna from rna tumor viruses and rna of other sources.fragmented 125i-labelled rna from rna tumor viruses was hybridized to unlabelled rna from cells, viruses, and homoribopolymers. the viral rna interacted with all rna tested, except for certain homoribopolymers. complex formation with unlabelled rna was verified by nuclease resistance, buoyant density measurements, and thermal stability in solutions of different ionic strength. the rnaase-resistant complex involved 20-30% of the sequences in the 125i-labelled viral rna and formed preferentially w ...1976183817
tunicamycin inhibits glycosylation and multiplication of sindbis and vesicular stomatitis viruses.tunicamycin (tm), an antibiotic that inhibits the formation of n-acetylglucosamine-lipid intermediates, thereby preventing the glycosylation of newly synthesized glycoproteins, inhibits the growth of sindbis virus and vesicular stomatitis virus in bhk cells. at 0.5 mug of tm per ml, the replication of both viruses is inhibited 99.9%. noninfectious particles were not detected. all the viral proteins were synthesized in the presence of tm, but the glycoproteins were selectively altered in that the ...1977189071
mechanism of premature polypetide termination in a mouse ascites cell-free system programmed by encephalomyocarditis viral rna.the premature termination and release of encephalomyocarditis viral rna-programmed polypeptides were analyzed in a cell-free system from mouse ascites tumor cells. the kcl concentration affects the size distribution of products but not the extent of polypeptide release. the same major products (60,000 to 140,000 molecular weight) are found in both the soluble and particulate fractions. the majority of released polypeptides are free protein, whereas the ribosome-bound product is mostly in the for ...1976178909
antiviral activity of an extract of brucella abortus: induction of interferon and immunopotentiation of host resistance. 1976181760
absence of 5' terminal capping in encephalomyocarditis virus rna.the nature of the 5' terminus of encephalomyocarditis (emc) virion rna has been investigated. we have failed to detect any capped products or nucleoside polyphosphates arising upon complete digestion of the rna with t1, t2, and pancreatic ribonucleases, and it would therefore appear that the 5' terminus of emc virus rna is not phosphorylated and not capped with m7g. emc virions do contain, however, large amounts of all four 5'-monosubstituted nucleoside triphosphates (4.2m pppg; 16.4m pppa; 3.om ...1976186763
size and location of poly (a) in encephalomyocarditis virus rna.encephalomyocarditis (emc) virus rna contains a covalently bound sequence of polyriboadenylic acid (poly(a). this was determined by two-dimensional gel electrophoresis of complete t1 and pancreatic rnase digests of formamidesucrose gradient-purified rna and subsequent analysis of the product by alkaline hydrolysis. the size of the emc virus genomic poly(a) sequence was estimated by formamide-polyacrylamide gel electrophoresis of the rnase-resistant product, or by [3h-]poly(u) hybridization to fr ...1976186764
possible in vitro repair of viral rna by ligase-like enzyme(s) in poliovirus-infected cells.a soluble polymerase-template complex prepared from poliovirus-infected cells was found to incorporate radioactive utp into trichloroacetic acid-insoluble rna linearly for 8 h in the presence of atp and mg2+. radioactive ctp or gtp was not incorporated under identical conditions. nearest-neighbor analysis of the in vitro product demonstrated that atp was added to the viral rna in the form of polyadenylic acid; utp was added internally to the 3'-oh group of all four nucelotides. the data can best ...1977189080
anti-viral activity against encephalomyocarditis virus and semliki forest virus and acute toxicity of poly i and poly c administered sequentially to mice.mice are protected against lethal intraperitoneal and intravenous infection by encephalomyocarditis virus and semliki forest virus by sequential treatment with poly i followed by either polyc or poly5-hydroxyc without production of interferon when the treatments are 4 or more hours apart and by the intraperitoneal or intravenous routes. maximum protection occurs around 4 hours before infection and is still significant 20 hours after infection. treatments with combinations of other homoribopolynu ...1976184760
genetic differences in susceptibility of pancreatic beta cells to virus-induced diabetes mellitus. 1976186716
stimulation of murine interferon by a substituted pyrimidine.2-amino-5-bromo-6-methyl-4-pyrimidinol (u-25,166) induced high levels of circulating interferon in mice when administered either parenterally or orally. peak titers of interferon were found in the serum between 6 and 12 h after inoculation of the drug. lower but significant levels of interferon were found in rat serum after administration of u-25,166 by either the intraperitoneal or oral route, and good levels of circulating interferon were observed in cats after oral treatment. repeated intrape ...1976176934
size of the poly(a) sequences in encephalomyocarditis virus rna.poly(a) sequences were demonstrated in the rna of encephalomyocarditis (emc) virus by affinity chromatography on poly(u)-sepharose, treatment with rnases, and determination of the ability of the rna to prime for reverse transcription. the size of the poly(a) sequences was estimated as 10-20 nucleotides in length by determination of the fraction resistant to pancreatic rnases plus t1 rnases, followed by analysis of electrophoretic mobility on polyacrylamide gels and of the amp-to-adenosine ratio ...1975187553
polyadenylation of ribonucleic acids in mouse l cells infected by encephalomyocarditis virus.polyadenylation of cytoplasmic rnas was investigated in l cells infected with encephalomyocarditis virus. during the early stage of infection, the mean size of newly made poly(a) chains attached to cell mrnas decreased gradually, in parallel with the shut-off of rna synthesis. later on, poly(a) segments, an average of 50 nucleotides long, were associated with viral rna isolated either from polysomes or whole cytoplasm. these segments seemed to be processed differently in the course of time, and ...1976187554
competition between cellular and viral mrnas in vitro is regulated by a messenger discriminatory initiation factor.encephalomyocarditis viral rna has previously been shown to outcompete host cellular mrna has for translation in vitro in crude and fractionated protein synthesizing systems. in the present communication it is shown that the competition is regulated by an initiation factor or complex of factors, and not the 40s initiation complex per se. the factor primarily involved is the murine equivalent of a component present in a partially purified preparation of rabbit initiation factor m3. both the murin ...1976184455
interferon-induced inhibition of protein synthesis in l-cell extracts: an atp-dependent step in the activation of an inhibitor by double-stranded rna.the translation of encephalomyocarditis virion rna in extracts from interferon-treated l-cells is inhibited by the addition of double-stranded rna (dsrna) at 400 ng/ml. a similar inhibition in response to dsrna is seen in control cell extracts supplemented with small amounts of a postribosomal supernatant fraction from interferon-treated cells (interferon cell sap): neither interferon cell sap nor dsrna alone is inhibitory in control systems. the inhibition is much reduced if translation is carr ...1976184463
viral spread in the presence of neutralizing antibody: mechanisms of persistence in foamy virus infection.several viruses were categorized on the basis of their ability to spread from cell to contiguous cell and form plaques in the presence of antiviral antibody. herpes simplex virus, cytomegalovirus, and vaccinia, measles, and foamy viruses were able to spread in the presence of neutralizing antibody, whereas coxsackievirus, encephalomyocarditis virus, vesicular stomatitis virus, mumps virus, and simian virus 5 failed to spread. a detailed study of one of these virus groups (simian foamy viruses) s ...1976185150
requirement of an adenylic acid-rich segment for the infectivity of encephalomyocarditis virus rna.about 80% of the rna molecules extracted from encephalomyocarditis (emc) virus were bound by oligo(dt)-cellulose under conditions which bind poly(a) but not poly(c) nor ribosomal rna. this shows that most emc virus rna molecules contain a poly(a) tract. both bound and unbound fractions contained rna molecules of apparently the same size when examined by sucrose gradient sedimentation, but the bound fraction contained an adenylic acid-rich segment of about 20 nucleotides long, whereas the unbound ...1976180245
photodynamic effect of toluidine blue on mm virus.the photodynamic effect of toluidine blue (tb) was studied on mm virus cultivated in l cells and on the rna extracted form mm virus inoculated to mice by intracerebral route. mm virus infectivity is completely inhibited by the photodynamic action of tb, due to lesions at the molecular level of the viral rna.1976188232
[virus-induced diabetes mellitus (author's transl)]. 1975188243
increase in lipid fluidity of cellular membranes induced by adsorption of rna and dna virions.changes in the dynamic behavior of membrane lipids of mammalian cells induced by adsorption of animal viruses were quantitatively monitored by fluorescence polarization analysis with the aid of the fluorescent probe 1,6-diphenyl 1,3,5-hexatriene embedded in the surface membrane lipid core of intact cells. adsorption of encephalomyocarditis, west nile, and polyoma viruses to hamster (baby hamster kidney) and mouse (3t3) cells is accompanied by a rapid and significant increase in the degree of flu ...1977194057
an integrated and comparative study of the antiviral effects and other biological properties of the polyinosinic-polycytidylic acid duplex and its mismatched analogues. iii. chronic effects and immunological features. 1976180397
aminoacylation of encephalomyocarditis virus rna.rna extracted from purified encephalomyocarditis (emc) virus (emc-rna) can be aminoacylated with synthetase praparations from escherichia coli, beef and rabbit liver. the extent of aminoacylation is between 0-024 and 0-080 moles per mole emc-rna and occurs only with serine. either removal of possible low mol. wt. contaminants with 3 m-sodium acetate nor periodate oxidation of the virus rna affects its aminoacylation capacity.1977188978
role of interferon in the pathogenesis of virus diseases in mice as demonstrated by the use of anti-interferon serum. i. rapid evolution of encephalomyocarditis virus infection.the role of interferon in the pathogenesis of encephalomyocarditis (emc) virus infection was determined by treating mice with potent, partially purified sheep anti-mouse interferon globulin. in control mice, emc virus was present in low titers in various visceral organs but attained high titers in the brain towards the 4th to 5th day, at which time mice died with signs of central nervous system disease. in mice treated with anti-mouse interferon globulin, virus was present in high titer in visce ...1976186554
the size and location of the poly(a) tract in emc virus rna.encephalomyocarditis (emc) virus rna, selected by its affinity for oligo(dt)-cellulose, contains poly(a) of size : (i) about 14 nucleotide residues long, based on the percentage of radioactivity in the rna resistant to digestion by a mixture of pancreatic and t1 rnases; (ii) about 15 residues long, as measured by the ratio of the amount of terminal adenosine to internal adenylic acid in isolated poly(a); and (iii) in the range 12 to 45 residues, the majority of tracts being about 16 to 18 residu ...1977190347
cellular protein synthesis shutoff by mengovirus: translation of nonviral and viral mrna's in extracts from uninfected and infected ehrlich ascites tumor cells.the mechanism whereby picornaviruses inhibit host protein synthesis while their own synthetic processes proceed unabated has remained elusive. one of our approaches to this problem was to study the ability of cell-free extracts derived from uninfected and mengovirus-infected ehrlich ascites tumor cells to translate viral and nonviral mrna's under various conditions of incubation. our results indicate that viral messengers (from mengovirus and encephalomyocarditis virus) and cellular messengers [ ...1976176460
protection of mice against encephalomyocarditis virus infection by preparations of transfer rna.preparations of bacterial transfer rna (trna), give dose-dependent protection of mice against encephalomyocarditis (emc) virus infection at up to i mg trna per mouse with maximum response when the trna is administered around 6 h before infection. protection occurs with intraperitoneally and intravenously administered trna against infections by both these routes. in some experiments significant protection occurs by single treatments of trna up to 24 h after infection with virus doses of i x ld100 ...1977188982
effect of virus infection and cycloheximide treatment on the labeling of cellular phospholipids with 32 p.the total amount and the relative proportions of labeled phospholipids were studied in chorioallantoic membrane cells (cam), chick embryo cells (cec) and l cells which were either infected with newcastle disease virus (ndv), fowl plague virus (fpv) and mouse encephalomyocarditis (emc) virus or treated with cycloheximide. in productively infected or nonproductively infected cells, the total amount of labeled phospholipids was not altered, but the relative proportions of individual phospholipids w ...1977192694
[immunologic demonstration of a cellular component in the composition of the rna polymerase of encephalomyocarditis virus]. 1977192524
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