Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| characterization and viral safety validation study of a pasteurized therapeutic concentrate of antithrombin iii obtained through affinity chromatography. | antithrombin iii (atiii) concentrates are employed as therapy for congenital or acquired deficiencies. these concentrates are obtained from cohn's fraction iv1. to improve yields, purity and safety, our group developed a procedure to obtain a pasteurized atiii concentrate from the supernatant of cohn's fraction ii + iii including a highly efficient heparin affinity chromatography purification and pasteurization as a viral inactivation step. | 1998 | 9592979 |
| a novel and efficient method for the stable expression of heteromeric ion channels in mammalian cells. | the 5' untranslated leader sequence from the encephalomyocarditis virus was used to engineer bicistronic or tricistronic expression vectors encoding two subunits (p2x2 and p2x3) of an atp-gated cation channel. human embryonic kidney (293) and chinese hamster ovary (cho-k1) cells were transfected with the vector, and stable cell lines were generated by single cell subcloning. selection was made in a 96-well format on the basis of a sustained increase in intracellular calcium (fluorescence of fluo ... | 1998 | 9606710 |
| the efficacy of an experimental oil-adjuvanted encephalomyocarditis vaccine in elephants, mice and pigs. | an oil-adjuvanted inactivated encephalomyocarditis (emc) vaccine was developed to protect a wild population of elephants against a natural outbreak of disease. the experimental vaccine was initially tested for efficacy by challenging mice and pigs. mice showed protection against challenge and pigs developed high antibody levels. since both vaccinated and control pigs failed to develop clinical disease, apparently due to the low virulence of the strain in this species, protection in pigs could no ... | 1998 | 9607009 |
| expression of human alpha 1 antitrypsin in murine hematopoietic cells in vivo after retrovirus-mediated gene transfer. | for patients with alpha1 antitrypsin (alpha 1at) deficiency, the expression of alpha 1at in hematopoietic cells may results in a number of benefits not provided by gene transfer strategies involving local modification of the respiratory epithelium or liver-directed gene transfer. we investigated the expression of alpha 1at in murine hematopoietic cells after retrovirus-mediated gene transfer. for this purpose we constructed an lnl-6-derived recombinant retrovirus vector (l alpha 1ed) that expres ... | 1998 | 9608542 |
| a small yeast rna blocks hepatitis c virus internal ribosome entry site (hcv ires)-mediated translation and inhibits replication of a chimeric poliovirus under translational control of the hcv ires element. | hepatitis c virus (hcv) infection frequently leads to chronic hepatitis and cirrhosis of the liver and has been linked to development of hepatocellular carcinoma. we previously identified a small yeast rna (irna) capable of specifically inhibiting poliovirus (pv) internal ribosome entry site (ires)-mediated translation. here we report that irna specifically inhibits hcv ires-mediated translation both in vivo and in vitro. a number of human hepatoma (huh-7) cell lines expressing irna were prepare ... | 1998 | 9621022 |
| nf-kappab-mediated inhibition of apoptosis is required for encephalomyocarditis virus virulence: a mechanism of resistance in p50 knockout mice. | apoptosis is a central host defense mechanism to eliminate virus-infected cells. activation of nf-kappab suppresses apoptosis following some types of stimulation in vitro. to test the physiological importance of this pathway in vivo, we studied murine encephalomyocarditis virus (emcv) infection in mice and cell lines defective in nf-kappab1 (p50) signaling. as previously reported, we find that all p50 knockout (p50 -/-) mice survive an emcv infection that readily kills normal mice. by introducin ... | 1998 | 9621024 |
| rapamycin and wortmannin enhance replication of a defective encephalomyocarditis virus. | inhibitors of the phosphatidylinositol 3-kinase (pi3 kinase)-fkbp-rapamycin-associated protein (frap) pathway, such as rapamycin and wortmannin, induce dephosphorylation and activation of the suppressor of cap-dependent translation, 4e-bp1. encephalomyocarditis virus (emcv) infection leads to activation of 4e-bp1 at the time of host translation shutoff. consistent with these data, rapamycin mildly enhances the synthesis of viral proteins and the shutoff of host cell protein synthesis after emcv ... | 1998 | 9621041 |
| the polypyrimidine tract binding protein (ptb) requirement for internal initiation of translation of cardiovirus rnas is conditional rather than absolute. | picornavirus rnas are translated by an unusual mechanism of internal ribosome entry that requires a substantial segment of the viral 5'-untranslated region, generally known as the internal ribosome entry segment (ires), and in some circumstances may require cellular trans-acting proteins, particularly polypyrimidine tract binding protein (ptb). it is shown here that for encephalomyocarditis virus (emcv), the ptb dependence of ires function in vitro is determined partly by the nature of the repor ... | 1998 | 9622122 |
| the 2-5a system: modulation of viral and cellular processes through acceleration of rna degradation. | the 2-5a system is an rna degradation pathway that can be induced by the interferons (ifns). treatment of cells with ifn activates genes encoding several double-stranded rna (dsrna)-dependent synthetases. these enzymes generate 5'-triphosphorylated, 2',5'-phosphodiester-linked oligoadenylates (2-5a) from atp. the effects of 2-5a in cells are transient since 2-5a is unstable in cells due to the activities of phosphodiesterase and phosphatase. 2-5a activates the endoribonuclease 2-5a-dependent rna ... | 1998 | 9623881 |
| internal ribosomal entry site-containing retroviral vectors with green fluorescent protein and drug resistance markers. | to facilitate gene delivery into animal cells we developed and characterized a family of single-transcript vectors (stvs) with different selection markers expressed from the internal ribosomal entry site (ires) of encephalomyocarditis virus (emcv). retroviral ires-stvs (r-ires-stvs) were assembled using an lncx backbone (miller and rosman, 1989). in all of these constructs, a multiple cloning site (mcs) is located immediately downstream of the single promoter and is followed by the ires sequence ... | 1998 | 9625263 |
| rnase l inhibitor (rli) antisense constructions block partially the down regulation of the 2-5a/rnase l pathway in encephalomyocarditis-virus-(emcv)-infected cells. | the interferon-(ifn)-inducible 2',5'-oligoadenylate (2-5a)/endoribonuclease l (rnase l) pathway plays a major role in the antiviral and antiproliferative effects of ifn. the 2-5a/rnase l pathway appears to be regulated by the cell-growth status or viral infection. viruses, and picornaviruses in particular, have evolved strategies to escape the 2-5a/rnase l-pathway-associated antiviral activity. we have recently cloned a cdna coding for rli, a rnase-l-specific protein inhibitor. its regulated exp ... | 1998 | 9660177 |
| translation eukaryotic initiation factor 4g recognizes a specific structural element within the internal ribosome entry site of encephalomyocarditis virus rna. | a complex of eukaryotic initiation factors (eifs) 4a, 4e, and 4g (collectively termed eif4f) plays a key role in recruiting mrnas to ribosomes during translation initiation. the site of ribosomal entry onto most mrnas is determined by interaction of the 5'-terminal cap with eif4e; eifs 4a and 4g may facilitate ribosomal entry by modifying mrna structure near the cap and by interacting with ribosome-associated factors. eif4g recruits uncapped encephalomyocarditis virus (emcv) mrna to ribosomes wi ... | 1998 | 9660832 |
| potential involvement of il-8 in the pathogenesis of human cytomegalovirus infection. | the observations that several types of viruses induced interleukin (il)-8 production prompted us to investigate the interrelationship between il-8 and cytomegalovirus (cmv) infection. cmv infection caused il-8 production in a human monocytic cell line, thp-1, in dose- and time-dependent manners. moreover, cmv induced il-8 gene expression by concurrently activating transcription factors, nf-kappab and ap-1. furthermore, cmv infection of human fibroblast cell lines increased gene expression of a s ... | 1998 | 9665276 |
| induction of virus-induced iddm in virus resistant mice without lymphocyte maturation. | the role of lymphocytes in the pathogenesis of viral-induced insulin dependent diabetes mellitus (iddm) is controversial. to better understand how a virus-induced iddm depends on the infiltrating lymphocytes, encephalomyocarditis virus (emcv) was inoculated intraperitoneally into three kinds of mice; virus-susceptible c57bl/6, virus-resistant 129/sv and recombination activity gene-2 (rag2) knockout 129/sv mice. pancreatic inflammation and beta cell necrosis were evaluated after emcv, d variant ( ... | 1998 | 9667762 |
| contrasting expression of kal in cell-free systems: 5' utr and coding region structural effects on translation. | we investigated the expression of two different x-linked kallmann (kal) gene cdnas in two different cell-free systems using rabbit reticulocyte lysate: (system a) transcription/translation coupled and (system b) noncoupled. system a yielded a single band of 76 kda corresponding to anosmin-1, the expected full-length gene product, and upon addition of canine microsomal membranes produced a 85-kda glycosylated form. system b did not produce any detectable protein band despite the expression of a b ... | 1998 | 9675068 |
| preservation of red cell properties after virucidal phototreatment with dimethylmethylene blue. | all published reports have described methods for virus photoinactivation which significantly alter red cell (rbc) properties during storage. in order to improve virucidal activity and reduce damage to rbcs, a series of phenothiazine derivatives were either synthesized or purified and screened for bacteriophage inactivation and red cell potassium efflux. one compound, 1,9-dimethylmethylene blue (dimethyl-methylene blue), had superior screening results and was chosen for further characterization. | 1998 | 9709780 |
| cytokines produced early in picornavirus infection reflect resistance or susceptibility to disease. | gender bias favoring female resistance to picornavirus disease is not seen in icr swiss mice following infection with the mm strain of encephalomyocarditis virus (emcv) (causing encephalitis and death) as it is with d variant of emcv (causing diabetes in males). to define this difference, an in vitro virus-infected splenocyte culture system was used to explore virus effects on lymphoid cells. infected and sham-infected splenocyte cultures, prepared from both genders of mice and infected with eit ... | 1998 | 9726440 |
| protection against lethal encephalomyocarditis virus infection in the absence of serum-neutralizing antibodies. | although the ability of serum-neutralizing antibodies to protect against picornavirus infection is well established, the contribution of cell-mediated immunity to protection is uncertain. using major histocompatibility complex class ii-deficient (rhabeta-/-) mice, which are unable to mediate cd4(+) t-lymphocyte-dependent humoral responses, we demonstrated antibody-independent protection against lethal encephalomyocarditis virus (emcv) infection in the natural host. the majority of rhabeta-/- mic ... | 1998 | 9733845 |
| denopamine, a beta1-adrenergic agonist, prolongs survival in a murine model of congestive heart failure induced by viral myocarditis: suppression of tumor necrosis factor-alpha production in the heart. | this study was designed to examine the effects of denopamine, a selective beta1-adrenergic agonist, in a murine model of congestive heart failure (chf) due to viral myocarditis. | 1998 | 9741531 |
| a dicistronic retroviral vector and culture model for analysis of neuron-schwann cell interactions. | a dicistronic retroviral gene delivery system and tissue culture model has been developed for studies of neuron-schwann cell interactions at the single cell level. the dicistronic retroviral vector contains a multiple cloning site followed by the encephalomyocarditis virus internal ribosomal entry site (emcv-ires) and a green fluorescent protein gene. this design allows for 5'-cap dependent translation of any gene of interest and 5'-cap independent translation of green fluorescent protein (gfp) ... | 1998 | 9765126 |
| the 3'-untranslated region of hepatitis c virus rna enhances translation from an internal ribosomal entry site. | translation of most eukaryotic mrnas and many viral rnas is enhanced by their poly(a) tails. hepatitis c virus (hcv) contains a positive-stranded rna genome which does not have a poly(a) tail but has a stretch of 98 nucleotides (x region) at the 3'-untranslated region (utr), which assumes a highly conserved stem-loop structure. this x region binds a polypyrimidine tract-binding protein (ptb), which also binds to the internal ribosome entry site (ires) in hcv 5'-utr. these rna-protein interaction ... | 1998 | 9765423 |
| a human liver cell line exhibits efficient translation of hcv rnas produced by a recombinant adenovirus expressing t7 rna polymerase. | an in vitro system that supports the efficient growth of hepatitis c virus (hcv) and reflects its complete in vitro replication cycle has not yet been established. the establishment of a minigene rna of hcv in mammalian cells could facilitate the study of virus-cell interactions and the molecular pathogenesis of this virus. we constructed a replication-deficient recombinant adenovirus expressing bacteriophage t7 rna polymerase under the control of cag promoter (adexcat7). a high level of t7 rna ... | 1998 | 9770428 |
| internal ribosomal entry site scanning of the poliovirus polyprotein: implications for proteolytic processing. | based on previous studies of dicistronic polioviruses carrying two internal ribosomal entry sites (ireses), we performed a novel experiment of ires scanning through a polypeptide by inserting sequentially the ires of encephalomyocarditis virus into the open reading frame (orf) of the poliovirus polyprotein at selected 3cpro-specific q*g cleavage sites. no cytopathic effects were observed after transfection of hela cells with any of the dicistronic constructs, and no virus was recovered. in vitro ... | 1998 | 9770438 |
| construction and characterization of single-transcript tricistronic retroviral vectors using two internal ribosome entry sites. | we describe a series of retroviral vectors containing two internal ribosome entry sites (ires) for the co-transcription of three genes. transcription of the single-transcript tricistronic mrna is under the control of a harvey murine sarcoma virus long terminal repeat. the 5'-most open reading frame is under either cap-dependent or cap-independent translational control, while the two downstream open reading frames are translated in a cap-independent fashion using the initiation codons of their re ... | 1998 | 9776981 |
| rapid establishment of high-producing cell lines using dicistronic vectors with glutamine synthetase as the selection marker. | recombinant proteins are useful tools in biological research, drug development, and drug screening. specially designed expression vectors have been developed to introduce cdna for recombinant protein expression in mammalian cells. we have combined a dicistronic mrna design for expression of the recombinant protein, using glutamine synthetase (gs) for selection. a soluble form of human interleukin-4 receptor alpha chain was used as the model protein. the dicistronic vectors were compared to a sta ... | 1998 | 9779420 |
| role of the vaccinia virus e3l and k3l gene products in rescue of vsv and emcv from the effects of ifn-alpha. | vaccinia virus (vv) has been shown to be relatively resistant to the antiviral effects of interferon-alpha (ifn-alpha) and to rescue replication of ifn-sensitive viruses, such as encephalomyocarditis virus (emcv) and vesicular stomatitis virus (vsv), from the antiviral effects of ifn. the e3l and k3l gene products have been implicated in the ifn resistance of vv. we have investigated the role that these vv-encoded functions play in the rescue of vsv and emcv from the effects of ifn. transient ex ... | 1998 | 9781811 |
| poor expression of mdr1 transgene in hela cells by bicistronic moloney murine leukemia virus-based vector. | cotransfer of a therapeutic gene together with the human mdr1 gene provides an opportunity to increase the number of transduced marrow cells, expressing the therapeutic gene, by in vivo selection for mdr1. we have used an lg-mdr1-ires-neo (lgmin) retroviral vector, containing mdr1 and neo genes, separated by the emcv ires. human hela or canine ctac cells, transduced with galv env pseudotyped lgmin at an moi of less than 0.01 to ensure 1 proviral copy/genome, were selected with either g418 for ne ... | 1998 | 9794210 |
| cis-acting rna elements required for replication of bovine viral diarrhea virus-hepatitis c virus 5' nontranslated region chimeras. | pestiviruses, such as bovine viral diarrhea virus (bvdv), share many similarities with hepatitis c virus (hcv) yet are more amenable to virologic and genetic analysis. for both bvdv and hcv, translation is initiated via an internal ribosome entry site (ires). besides ires function, the viral 5' nontranslated regions (ntrs) may also contain cis-acting rna elements important for viral replication. a series of chimeric rnas were used to examine the function of the bvdv 5' ntr. our results show that ... | 1998 | 9814762 |
| coexpression of a multidrug-resistance gene (mdr1) and herpes simplex virus thymidine kinase gene as part of a bicistronic messenger rna in a retrovirus vector allows selective killing of mdr1-transduced cells | a new retroviral vector, psxlc/pha, was constructed to coexpress drug-selectable markers with a second gene of interest as a part of a bicistronic mrna in a retroviral vector using an internal ribosome entry site (ires) from encephalomyocarditis virus. this system was used to develop a new retroviral vector pha-mdr-ires-tk which expresses a single mrna from which translation of the mdr1 gene is cap dependent and translation of the herpes simplex virus thymidine kinase gene is ires dependent. the ... | 1995 | 9816003 |
| identification of encephalomyocarditis virus in clinical samples by reverse transcription-pcr followed by genetic typing using sequence analysis. | the objective of the present study was to gain a better understanding of the epidemiology of encephalomyocarditis virus (emcv) infections in pigs by applying molecular techniques. the diagnostic potential of a reverse transcription-pcr (rt-pcr) targeting 286 nucleotides at the 3' end of the gene which encodes the viral polymerase was assessed with experimental and field samples. in addition, the use of the amplified sequences for an epidemiological study was evaluated. the heart was clearly show ... | 1998 | 9817855 |
| molecular analysis of encephalomyocarditis viruses isolated from pigs and rodents in italy. | partial nucleotide sequences of encephalomyocarditis (emc) viruses isolated from five, apparently independent, outbreaks of fatal myocarditis in pigs in italy were compared with three emc viruses isolated from wild rodents from a different geographic region in the same country. these viruses were also compared with emc viruses isolated from pigs in other european countries and three historical strains. all the italian emc viruses were closely related (> 94.6% nucleotide identity), but were disti ... | 1998 | 9833886 |
| inhibition of internal entry site (ires)-mediated translation by a small yeast rna: a novel strategy to block hepatitis c virus protein synthesis. | the observation that poliovirus mrna is not translated in the yeast saccharomyces cerevisiae has led to the discovery of a small rna (60 nt, called irna, inhibitor rna) which was later shown to specifically inhibit internal ribosome entry site (ires)-mediated translation of naturally uncapped mrnas. translation of cellular capped mrnas was not significantly inhibited by irna. irna also specifically inhibited hepatitis c virus (hcv) ires-mediated translation in vitro and in vivo. a hepatoma cell ... | 1998 | 9835647 |
| a serine elastase inhibitor reduces inflammation and fibrosis and preserves cardiac function after experimentally-induced murine myocarditis. | in viral myocarditis, inflammation and destruction of cardiac myocytes leads to fibrosis, causing progressive impairment in cardiac function. here we show the etiologic importance of serine elastase activity in the pathophysiology of acute viral myocarditis and the therapeutic efficacy of an elastase inhibitor. in dba/2 mice inoculated with the encephalomyocarditis virus, a more than 150% increase in myocardial serine elastase activity is observed. this is suppressed by a selective serine elasta ... | 1998 | 9846575 |
| down regulation of gene expression by the vaccinia virus d10 protein. | vaccinia virus genes are expressed in a sequential fashion, suggesting a role for negative as well as positive regulatory mechanisms. a potential down regulator of gene expression was mapped by transfection assays to vaccinia virus open reading frame d10, which encodes a protein with no previously known function. inhibition was independent of the promoter type used for the reporter gene, indicating that the mechanism did not involve promoter sequence recognition. the inhibition was overcome, how ... | 1999 | 9847390 |
| drug-selected complete restoration of superoxide generation in epstein-barr virus-transformed b cells from p47phox-deficient chronic granulomatous disease patients by using a bicistronic retrovirus vector encoding a human multi-drug resistance gene (mdr1) and the p47phox gene. | chronic granulomatous disease (cgd) is a group of disorders characterized by the failure of phagocytes to produce superoxide. one-third of the cases of cgd in the usa and europe results from defects in the gene encoding p47phox, a cytoplasmic component of nadph oxidase for superoxide generation. in this study, we constructed the bicistronic retrovirus vector ha-mdr-ires-p47, which carries cdnas for a human multi-drug-resistance gene (mdr1) and p47phox. the amphotropic retroviral producer cells w ... | 1998 | 9856484 |
| impact of rnase l overexpression on viral and cellular growth and death. | the biologic actions of interferons (ifns) are complex and involve multiple biochemical mechanisms, including the 2-5a system, a regulated rna decay pathway. the 2-5a system is implicated in the antipicornavirus activity of ifn and in the control of apoptosis. to further investigate involvement of the 2-5a system in the control of viral and cellular growth and death, human rnase l cdna was stably expressed in murine 3t3 cells from a constitutive cytomegalovirus (cmv) promoter. a clonal cell line ... | 1998 | 9858317 |
| the rnase l inhibitor (rli) is induced by double-stranded rna. | the (2-5a)-rnase l pathway is an important component of interferon (ifn) action. its central role in the antiviral effect of ifn against picornaviridae has been clearly demonstrated. we have characterized and cloned a new component of this pathway, the rnase l inhibitor (rli). rli is a cellular protein whose mrna is not regulated by ifn but is induced by viruses, such as encephalomyocarditis virus (emcv). rli inhibits rnase l during the time course of emcv infection, and overexpression of rli in ... | 1998 | 9877446 |
| defective induction of the transcription factor interferon-stimulated gene factor-3 and interferon alpha insensitivity in human trophoblast cells. | during pregnancy, trophoblast cells of the placenta contact maternal immune cells and yet are protected from attack. one mechanism that may account for this is that trophoblasts show altered expression of major histocompatibility complex (mhc) antigens. the gene for human leukocyte antigen g (hla-g), a nonclassical gene, is expressed at high levels in trophoblast. unlike other mhc class i genes, the hla-g gene lacks an interferon (ifn) response element. moreover, we demonstrate here that ifn, wh ... | 1999 | 9915996 |
| inducible expression of herpes simplex virus thymidine kinase from a bicistronic hiv1 vector. | the possibility of protecting human cd4+ lymphocytes from human immunodeficiency virus type 1 (hiv1) infection, through a suicide mechanism elicited by the hiv1 transcription apparatus itself, offers a potentially useful approach for gene therapy of the acquired immunodeficiency syndrome. a replication-defective lentiviral hiv1 vector (hyires-tk) was designed to carry both the hygromycin (hy) phosphotransferase gene for positive selection and the thymidine kinase (tk) gene of herpes simplex viru ... | 1998 | 9923018 |
| gene transfer using a disabled herpes virus vector containing the emcv ires allows multiple gene expression in vitro and in vivo. | the design of recombinant hsv-1 vectors for delivery of transgenes to the central nervous system is undergoing constant development. problems associated with the construction and use of such vectors include the requirement for detection of recombinant versus nonrecombinant virus in vitro and also the identification of transduced cells in vivo. this could be overcome by the insertion of reporter genes such as lacz or green fluorescent protein (gfp) under a separate promoter to the transgene to be ... | 1998 | 9930311 |
| highly sensitive detection of swine vesicular disease virus based on a single tube rt-pcr system and dig-elisa detection. | a highly sensitive detection of swine vesicular disease virus (svdv) based on a single tube rt-pcr system and digoxigenin (dig)-pcr-elisa detection was developed. using a one tube rt-pcr system, optimisation of the pcr conditions and optimisation of the microwell hybridisation and colourimetric detection of the amplicons resulted in a method that could detect viral rna in infected tissue culture fluid with a titre as low as 0.1 tcid50/100 microl. the same sensitivity was obtained with svdv-spike ... | 1999 | 10029329 |
| use of an internal ribosome entry site for bicistronic expression of cre recombinase or rtta transactivator. | conditional gene targeting depends on tissue and time specificity of recombination events. endogenous promoters are often used to drive various transgenic constructs. to avoid the problems associated with reconstituting a specific expression pattern in transgenic animals by this method, we tested the internal ribosome entry site of the encephalomyocarditis virus, to enable linkage of the cre recombinase or rtta trans-activator to 3' untranslated ends of endogenous genes. here we report that thes ... | 1999 | 10037820 |
| affinity purification of recombinant interferon-alpha on a mimetic ligand adsorbent. | a method for improved refolding and purification of recombinant human interferon-alpha (rh-ifn-alpha) from inclusion bodies is described. the optimal conditions of refolding were obtained by the addition of 0.5 m l-arginine to the refolding buffer. the rh-ifn-alpha was purified to near homogeneity utilizing a single-step chromatography on a mimetic dye-ligand matrix. improved refolding, coupled to a single-column affinity purification strategy, resulted in a 10-fold increase in the yield of rh-i ... | 1999 | 10049681 |
| heat stress aggravates viral myocarditis in mice. | while a beneficial effect of hyperthermia on viral infection has been hypothesized, there are no data on viral myocarditis in vivo. to investigate whether hyperthermia might attenuate the course or severity of viral myocarditis, we studied the pathological changes in a murine model of viral myocarditis. c3h mice were inoculated i.p. with the encephalomyocarditis virus (500 pfu). they were anesthetized and heated to a body temperature of 42.5+/-0.2 degrees c for 30 min. the latter was performed 4 ... | 1999 | 10069487 |
| increased severity of viral myocarditis in mice lacking lymphocyte maturation. | the role of lymphocytes in the pathogenesis of viral myocarditis is controversial. to better understand how lymphocyte maturation controls a virus-induced myocarditic process, a murine model of viral myocarditis was utilized. encephalomyocarditis virus (emcv) was inoculated intraperitoneally into three kinds of mice; virus-susceptible c57bl/6, virus-resistant 129/sv and recombination activity gene (rag)-2 knockout 129/sv mice. the rag2 participate in the maturity of t and b lymphocytes. survival ... | 1999 | 10077396 |
| interferon-induced guanylate binding protein-1 (gbp-1) mediates an antiviral effect against vesicular stomatitis virus and encephalomyocarditis virus. | a cdna encoding the human guanylate binding protein-1 (hgbp-1) was expressed in hela cells using a constitutive expression vector. stably transfected clones expressing hgbp-1 exhibited resistance to the cytopathic effect mediated by both vesicular stomatitis virus (vsv) and encephalomyocarditis virus (emcv) and produced less viral progeny than control cells following infection with these viruses. to study the role hgbp-1 plays in the ifn-mediated antiviral effect, cells were stably transfected w ... | 1999 | 10087221 |
| antibody response in baboons (papio cynocephalus anubis) to a commercially available encephalomyocarditis virus vaccine. | 1998 | 10090069 | |
| oromucosal interferon therapy: marked antiviral and antitumor activity. | oromucosal administration of murine interferon-alpha/beta (ifn-alpha/beta) or individual recombinant species of murine ifn-alpha, ifn-beta, or ifn-gamma or recombinant human ifn-alpha1-8, which is active in the mouse, exerted a marked antiviral activity in mice challenged systemically with a lethal dose of encephalomyocarditis virus (emcv), vesicular stomatitis virus (vsv), or varicella zoster virus (vzv). the effects observed were dose dependent and similar in magnitude to those observed follow ... | 1999 | 10090400 |
| identification and characterization of a protein destruction signal in the encephalomyocarditis virus 3c protease. | the amino acid sequence llvrgrtlvv, which is probably located in a strand-turn-strand structure, has been identified as a protein destruction signal in the rapidly degraded encephalomyocarditis virus 3c protease. mutations within this sequence reduced the susceptibility of the 3c protease toward ubiquitination and degradation in rabbit reticulocyte lysate. this signal is transferable, since poliovirus 3c protease, which is a poor ubiquitin-mediated proteolytic system substrate, was found to be u ... | 1999 | 10092679 |
| identification and characterization of a protein destruction signal in the encephalomyocarditis virus 3c protease | the amino acid sequence llvrgrtlvv, which is probably located in a strand-turn-strand structure, has been identified as a protein destruction signal in the rapidly degraded encephalomyocarditis virus 3c protease. mutations within this sequence reduced the susceptibility of the 3c protease toward ubiquitination and degradation in rabbit reticulocyte lysate. this signal is transferable, since poliovirus 3c protease, which is a poor ubiquitin-mediated proteolytic system substrate, was found to be u ... | 1999 | 10092683 |
| characterization of the effects of hepatitis c virus nonstructural 5a protein expression in human cell lines and on interferon-sensitive virus replication. | the hepatitis c virus (hcv) nonstructural 5a (ns5a) protein has been implicated in the inherent resistance of hcv to interferon (ifn) antiviral therapy in clinical studies. biochemical studies have demonstrated that ns5a interacts in vitro with and inhibits the ifn-induced, rna-dependent protein kinase, pkr, and that ns5a interacts with at least one other cellular kinase. the present study describes the establishment and characterization of various stable ns5a-expressing human cell lines, and th ... | 1999 | 10094974 |
| ptrident, a novel vector family for tricistronic gene expression in mammalian cells. | we constructed tricistronic expression vectors for the simultaneous and coordinated expression of three independent genes in mammalian cells. one single promoter allows high level and, in some vectors, adjustable transcription of all three cistrons. whereas the first cistron is translated in a cap-dependent manner, the subsequent ones utilize intercistronic regions of viral origin such as the internal ribosomal entry site of poliovirus or the cap-independent translation enhancer of encephalomyoc ... | 1998 | 10099172 |
| pimobendan inhibits the production of proinflammatory cytokines and gene expression of inducible nitric oxide synthase in a murine model of viral myocarditis. | this study was designed to examine the effects of pimobendan in a murine model of viral myocarditis in relation to proinflammatory cytokine production and nitric oxide (no) synthesis by inducible no synthase (inos) in the heart. | 1999 | 10193745 |
| efficient bicistronic expression of cre in mammalian cells. | cre recombinase-mediated dna recombination is proving to be a powerful technique for the generation of mosaic mutant mice. to develop this technology further, we have altered the cre gene to enhance its expression in mammalian cells and have tested its efficiency of expression in a bicistronic message. using a transient transfection assay, we found that the extension of a eukaryotic translation initiation consensus sequence, the insertion of two n-terminal amino acids, and the mutation of a cryp ... | 1999 | 10198442 |
| virus reduction in the preparation of intravenous immune globulin: in vitro experiments. | while immune globulins for intravenous administration (igiv) have an excellent record with respect to virus safety, concern regarding these preparations has been raised by reports of transmission of hepatitis c virus (hcv) to patients treated with igiv and the presence of genetic material for hcv in igiv preparations. | 1999 | 10204586 |
| targeted overexpression of elafin protects mice against cardiac dysfunction and mortality following viral myocarditis. | serine elastases degrade elastin, stimulate vascular smooth muscle cell migration and proliferation, and are associated with myocardial damage. to evaluate the impact of elastase inhibition on cardiovascular development and disease, transgenic mice were created in which the mouse preproendothelin-1 promoter was used to target elafin overexpression to the cardiovascular system. to distinguish the transgene from endogenous elafin, constructs were made incorporating a flag sequence; the cooh-termin ... | 1999 | 10207173 |
| the ns5a protein of hepatitis c virus partially inhibits the antiviral activity of interferon. | the non-structural protein 5a (ns5a) of some hepatitis c virus (hcv) isolates has been implicated in the inhibition of the antiviral activity of interferon (ifn). in the present study, the possible inhibitory effects of ns5a from two isolates of hcv subtype 1b, hcv-1bjk and m094ajk, and their chimeric form on the antiviral activity of ifn were examined. hcv-1bjk and m094ajk are categorized as ifn resistant and ifn sensitive, respectively, based on the sequences of the ifn-sensitivity determining ... | 1999 | 10211956 |
| the expression of both domains of the 69/71 kda 2',5' oligoadenylate synthetase generates a catalytically active enzyme and mediates an anti-viral response. | the 2',5' oligoadenylate synthetase (oas) represents a family of interferon-induced proteins which, when activated by double-stranded (ds) rna, polymerizes atp into 2',5'-linked oligomers with the general formula pppa(2'p5'a)n, where n >/= 1. the 69-kda form of human oas has two isoforms (p69 and p71) that are identical for their first 683 amino acids and consist of two homologous and adjacent domains, each homologous to the small 40-kda oas. here, we demonstrate that mrna species specific for t ... | 1999 | 10231377 |
| murine viruses in an island population of introduced house mice and endemic short-tailed mice in western australia. | house mice (mus domesticus) were recently introduced to thevenard island, off the northwest coast of western australia. this island is also habitat for an endangered native rodent, the short-tailed mouse (leggadina lakedownensis). concerns have been raised that house mice may pose a threat to l. lakedownensis both through competition and as a source of infection. to assess the threat to l. lakedownensis posed by viral pathogens from m. domesticus, a serological survey was conducted from 1994 to ... | 1999 | 10231757 |
| genetically engineered mengo virus vaccination of multiple captive wildlife species. | encephalomyocarditis virus (emcv), has caused the deaths of many species of animals in zoological parks and research institutions. the audubon park zoo, (new orleans, louisiana, usa) attempted vaccination of several species with a killed emcv vaccine with mixed results. this paper reports an attempt at vaccination against emcv using a genetically engineered, live attenuated mengo virus (vmc0) at the audubon park zoo and miami metro zoo, (miami, florida, usa) from december 1996 to june 1997. seve ... | 1999 | 10231768 |
| encephalomyocarditis (emc) virus infection in pc12 and c6 cells. | pc12 cells derived rom rat pheochromocytoma and c6 cells derived from rat glioma were infected with 0.3 plaque forming units (pfu)/cell of the d variant of encephalomyocarditis virus (emc-d), after pretreatment with or without nerve growth factor (ngf). the virus titres in medium and cells were investigated at 6, 12, 24, 48 and 72 h post infection (hpi), and histopathology and viral antigens in cells were examined at 24 and 48 hpi, respectively. as a result, neither viral replication nor light a ... | 1998 | 10319021 |
| interstitial fibrin-fibronectin deposition with t cell infiltrates precedes fibrosis in murine viral myocarditis. | this study was carried out to investigate interstitial fibrin and fibronectin deposition and subsequent myocardial connective tissue abnormalities in balb/c-nu/+ (euthymic and normal t cell function) and balb/c-nu/nu (athymic and t cell-deficient) mice. both types of mice were inoculated with encephalomyocarditis virus and sacrificed periodically. sections of the hearts were stained with haematoxylin-eosin, trichrome, lymphocyte subsets, silver impregnation, and fibrin or fibronectin. in additio ... | 1998 | 10319022 |
| a mechanism for selective induction of 2'-5' oligoadenylate synthetase, anti-viral state, but not mhc class i genes by interferon-beta in neurons. | interferon-inducible expression of major histocompatibility class i genes has previously been found to be quantitatively and functionally deficient in neurons compared to other somatic cells or other neural cell types including astrocytes. this deficiency is a key component of neuronal immunoprivilege during viral infections of the cns. to the contrary, in the present study, induction of functional antiviral state by ifn-beta in neurons compared to astrocytes was found to be highly efficient wit ... | 1999 | 10321980 |
| pires-cd4t, a dicistronic expression vector for macs- or facs-based selection of transfected cells. | to facilitate the selection of cell lines expressing transfected genes of interest, a plasmid vector has been constructed that directs the co-expression of heterologous cdnas and a 3'-positioned cassette encoding a truncated cd4 marker. an encephalomyocarditis virus internal ribosomal entry site (ires) mediates translational initiation from this 3' cassette, and a cytomegalovirus promoter drives dicistronic transcript expression. to test the utility of this vector, a luciferase reporter gene was ... | 1999 | 10343906 |
| interferon action in triply deficient mice reveals the existence of alternative antiviral pathways. | antiviral proteins encoded by the interferon (ifn)-stimulated genes provide a front-line defense against viral infections. in particular, pkr, rnase l, and mx are considered to be the principal proteins through which ifns mount an antiviral state. to determine whether alternative antiviral pathways exist, rnase l-/- mice and pkr-/- mice were crossed onto an mx1(-/-) background to generate a strain of triply deficient (td) mice. after infections with encephalomyocarditis virus, the td mice died 3 ... | 1999 | 10366581 |
| the properties of chimeric picornavirus ireses show that discrimination between internal translation initiation sites is influenced by the identity of the ires and not just the context of the aug codon. | the internal ribosome entry segment (ires) of picornaviruses consists of approximately 450 nt of 5'-untranslated region, terminating at the 3' end with an approximately 25 nt element consisting of an absolutely conserved uuuc motif followed by a more variable pyrimidine-rich tract and g-poor spacer, and finally an aug triplet, which is considered to be the actual ribosome entry site. events following entry at this site differ among picornaviruses: in encephalomyocarditis virus (emcv) virtually a ... | 1999 | 10376876 |
| epidemiologic, pathogenic and molecular analysis of recent encephalomyocarditis outbreaks in belgium. | in 1991 emcv was isolated for the first time in belgium from the offspring of a sow with reproductive failure. from august 1995 until december 1996, emcv was diagnosed in 154 belgian pig holdings in association with myocardial failure and sudden death in fatteners and suckling piglets or with reproductive failure in sows. to clarify some epidemiological aspects 3 emcv isolates characteristic for the different clinical pictures and outbreaks were studied. field observations and animal experiments ... | 1999 | 10379232 |
| failure to detect antiviral activity in serum and plasma of healthy individuals displaying high activity in elisa for ifn-alpha and ifn-beta. | the presence of constitutively produced interferon (ifn)-alpha in the blood of healthy individuals has been the subject of contradictory discussions for years. immunologic as well as biologic test procedures have demonstrated striking differences regarding serum ifn-alpha under physiologic conditions. we investigated the presence of immunoreactive ifn-alpha in serum samples of 923 healthy blood donors by means of a widely used commercially available elisa. of these, 254 (27.5%) exhibited detecta ... | 1999 | 10386858 |
| virus validation of ph 4-treated human immunoglobulin products produced by the cohn fractionation process. | to assess the virus reducing capacity of cohn's cold ethanol fractionation process for the production of intravenous (ivig) and intramuscular (imig) immunoglobulin products, and treatment of these products at ph 4, a validation study of virus removal and/or inactivation was performed using both lipid-enveloped viruses [human immunodeficiency virus (hiv), bovine viral diarrhoea virus (bvdv) and pseudorabies virus (psr)], and non-lipid-enveloped viruses [(simian virus 40 (sv40) and encephalomyocar ... | 1998 | 10403030 |
| removal of viruses from human intravenous immune globulin by 35 nm nanofiltration. | viral safety is an important prerequisite for clinical immunoglobulin preparations. a common manufacturing practice is to utilize several virus removal/inactivation process steps to ensure the safety of human intravenous immunoglobulin (ivig). in this regard, we examined the use of planova 35 nm filters to reduce potential loads of both non-enveloped and enveloped viruses prior to end-stage solvent detergent treatment. the nanofiltration process was validated for removal of a variety of envelope ... | 1998 | 10403036 |
| quantification of endogenous viral polymerase, 3d(pol), in preparations of mengo and encephalomyocarditis viruses. | measurement of an antigenic response to the aphthovirus infection-associated antigen (via), the viral rna polymerase 3d(pol), is frequently used as a discriminating assay for the extent of viral replication in animals. in practice, animals seropositive for via are assumed to have been exposed to live virus, although in fact it is suspected that endogenous 3d(pol) in commercial inactivated vaccines may occasionally stimulate analogous responses and result in false-positive tests for virus exposur ... | 1999 | 10405366 |
| phylogenetic analysis of european encephalomyocarditis viruses: comparison of two genomic regions. | the phylogenetic relationships of encephalomyocarditis (emc) viruses isolated from pigs and rodents in europe were determined by comparison of nucleotide sequences from two different regions of the virus genome, the vp3/vp1 gene junction (part of the capsid-coding region) and part of the 3d polymerase-coding region. thirty-five european emc viruses could be divided into two genetic groups, one which contained viruses from greece isolated between 1986 and 1997 and from belgium in 1991 and the oth ... | 1999 | 10416373 |
| construction and characterization of a recombinant adenoviral vector expressing human interleukin-12. | interleukin-12 (il-12) is a 70-kda heterodimeric cytokine composed of a 35-kda subunit (p35) and a 40-kda subunit (p40). we have demonstrated previously that intratumoral delivery of a recombinant adenoviral vector expressing the mouse il-12 gene significantly prolongs the survival time of mice with metastatic colon carcinoma in the liver. we now report the molecular cloning of cdna for both subunits of human il-12 (hil-12) in a recombinant adenoviral vector in which the p40 and p35 subunits are ... | 1999 | 10419056 |
| evolution of a cytokine using dna family shuffling. | dna shuffling of a family of over 20 human interferon-alpha (hu-ifn-alpha) genes was used to derive variants with increased antiviral and antiproliferation activities in murine cells. a clone with 135,000-fold improved specific activity over hu-ifn-alpha2a was obtained in the first cycle of shuffling. after a second cycle of selective shuffling, the most active clone was improved 285,000-fold relative to hu-ifn-alpha2a and 185-fold relative to hu-ifn-alpha1. remarkably, the three most active clo ... | 1999 | 10429246 |
| inhibitory activity of constitutive nitric oxide on the expression of alpha/beta interferon genes in murine peritoneal macrophages. | we investigated the role of the constitutive nitric oxide (no) in the expression of interferon (ifn) genes in mouse peritoneal macrophages (pm). the treatment of pm with l-arginine-n(g)-amine (aa), a potent inhibitor of no-producing enzymes, resulted in a marked accumulation of ifn-alpha4 mrna and, to a minor extent, of ifn-beta mrna. in contrast, the expression of ifn-gamma mrna, as well as tumor necrosis factor alpha and interleukin-6 mrna, was not affected. furthermore, a remarkable increase ... | 1999 | 10438821 |
| evidence for irf-1-dependent gene expression deficiency in interferon unresponsive hepg2 cells. | induction of the antiproliferative and antiviral state by ifns (type i and ii) is dramatically impaired in hepg2 cells. we show here that rnase l, ido, gbp-2 and inos genes normally expressed as a secondary response to ifn are no longer inducible in hepg2 cells, while induction of primary response genes (irf-1, pkr, p48-isgf3gamma, 2-5as, 6-16 and p56-(trp)trna) are unaffected. on the basis of previous data implicating transcription factor irf-1 in the induction of some ifn-induced genes, we tes ... | 1999 | 10446388 |
| three-color flow cytometry analysis of tricistronic expression of ebfp, egfp, and eyfp using emcv-ires linkages. | the ability to quickly analyze and sort double or triple fluorescent reporter constructs using simultaneous analysis provides significant flexibility in the solution of analytical and process-related questions in biotechnology. | 1999 | 10451506 |
| bicistronic retroviral vectors for combining myeloprotection with cell-surface marking. | we have developed a retroviral vector coexpressing the multidrug-resistance 1 (mdr1) cdna for inducing cancer drug resistance and the truncated version of the low-affinity nerve growth factor receptor (deltalngfr) for cell-surface marking of transduced cells. the vector is based on the fmev backbone which mediates high levels of gene expression in hematopoietic cells. to achieve optimal expression levels of both cdnas, untranslated regions from mdr1 and deltalngfr were removed and three differen ... | 1999 | 10455430 |
| acceleration of viral replication and up-regulation of cytokine levels by antimalarials: implications in malaria-endemic areas. | antimalarial drugs are widely used in malaria endemic areas, both for chemoprophylaxis and also empirically to treat patients presenting with fever. previously, we have reported that chloroquine enhances the severity of semliki forest virus (sfv) and encephalomyocarditis virus infection. the studies presented herein show that a broad spectrum of antimalarial drugs augmented the replication of sfv in mice, concomitant with greater tissue damage and up-regulation of mrna levels of various inflamma ... | 1999 | 10463664 |
| mucosal cytokine therapy: marked antiviral and antitumor activity. | mucosal administration of the th1 stimulatory cytokines interleukin-2 (il-2), il-12, il-15, il-18, or granulocyte-macrophage colony-stimulating factor (gm-csf) induced antiviral activity in mice challenged systemically with a lethal dose of encephalomyocarditis virus (emcv) similar to that observed following parenteral administration. in contrast, mucosal administration of the th2 stimulatory cytokines il-4, il-5, il-10, or il-13 did not affect significantly the survival of emcv-infected animals ... | 1999 | 10476938 |
| treatment of experimental viral myocarditis with interleukin-10. | the t helper cell type 2-associated cytokine interleukin (il)-10 has a variety of immunomodulatory properties. however, the effects of the cytokine on viral myocarditis remain unclear. | 1999 | 10477536 |
| prevention of encephalomyocarditis virus-induced diabetes in mice by inhibition of the tyrosine kinase signalling pathway and subsequent suppression of nitric oxide production in macrophages. | macrophages comprise the major population of cells infiltrating pancreatic islets during the early stages of infection in dba/2 mice by the d variant of encephalomyocarditis virus (emc-d virus). inactivation of macrophages prior to viral infection almost completely prevents emc-d virus-induced diabetes. this investigation was initiated to determine whether a tyrosine kinase signalling pathway might be involved in the activation of macrophages by emc-d virus infection and whether tyrosine kinase ... | 1999 | 10482607 |
| [para-aminobenzoic acid--an interferon inducer]. | para-aminobenzoic acid (paba) was shown to be an early type interferon inductor. paba (10 micrograms/ml) induced interferon production in vitro in the cells of human peripheral blood and in vivo in albino mice (10 mg/kg). the results of the study suggested that paba was able to induce production of interferon-alpha/beta in various immunocyte populations. by its interferonogenic activity paba was comparable with the known interferon inductors. one of the mechanisms of the previously described in ... | 1999 | 10483491 |
| the interferon-inducible 204 gene, a member of the ifi 200 family, is not involved in the antiviral state induction by ifn-alpha, but is required by the mouse cytomegalovirus for its replication. | to examine whether ifi 200 genes are involved in antiviral state induction by ifns we expressed mutant forms capable of inactivating the endogenous p204 and analyzed replication of both rna and dna viruses following ifn-alpha treatment. inactivation of p204 does not impair replication of vesicular stomatitis virus, encephalomyocarditis virus, ectromelia virus, and herpes simplex virus 1 and does not alter an ifn-alpha induced antiviral state. by contrast, in cells lacking functional p204, mouse ... | 1999 | 10489335 |
| a selection system for functional internal ribosome entry site (ires) elements: analysis of the requirement for a conserved gnra tetraloop in the encephalomyocarditis virus ires. | picornavirus internal ribosome entry site (ires) elements direct cap-independent internal initiation of protein synthesis within mammalian cells. these rna elements (about 450 nt) contain extensive secondary structure including a hairpin loop with a conserved gnra motif. such loops are important in rna-rna and rna-protein interactions. plasmids that express dicistronic mrnas of the structure gus/ires/hook have been constructed. the hook sequence encodes a cell-surface-targeted protein (sfv); the ... | 1999 | 10496218 |
| the structures of picornaviral proteinases. | picornaviruses are a family of positive-strand rna viruses the members of which include poliovirus, hepatitis a virus, rhinovirus, foot-and-mouth disease virus and encephalomyocarditis virus. the genetic information contained in the single-stranded, positive sense rna genome is expressed as a single protein of around 2000 amino acids. this primary product of protein synthesis, designated the polyprotein, is subsequently cleaved into the mature viral proteins by proteinases present within it. the ... | 1999 | 10507325 |
| the use of bi-cistronic transfer vectors for the baculovirus expression system. | in this communication, we describe the construction of bi-cistronic transfer vectors for the baculovirus expression system (bves), which are advantageous over the existing vectors. the new vectors provide a simple way to isolate recombinant viruses. more specifically, the gene of interest and the reporter gene luciferase (luc), constitute the first and second cistrons, respectively, of the same transcript. therefore, the luc activity measured during infection of such a bi-cistronic virus, permit ... | 1999 | 10510857 |
| picornavirus internal ribosome entry site elements target rna cleavage events induced by the herpes simplex virus virion host shutoff protein. | the herpes simplex virus (hsv) virion host shutoff (vhs) protein (ul41 gene product) is a component of the hsv virion tegument that triggers shutoff of host protein synthesis and accelerated mrna degradation during the early stages of hsv infection. vhs displays weak amino acid sequence similarity to the fen-1 family of nucleases and suffices to induce accelerated rna turnover through endoribonucleolytic cleavage events when it is expressed as the only hsv protein in a rabbit reticulocyte in vit ... | 1999 | 10516030 |
| double-stranded rna-activated protein kinase mediates virus-induced apoptosis: a new role for an old actor. | 1999 | 10518510 | |
| inhibitory role of the host apoptogenic gene pkr in the establishment of persistent infection by encephalomyocarditis virus in u937 cells. | persistent infections by viruses such as hiv-1 and hepatitis b virus can pose long-term health hazards. because establishment of persistent infections involves close interactions and adjustments in both host and virus, it would be informative to establish a paradigm with which a normally cytolytic viral infection can be easily converted to persistent infection, so that the different stages in developing persistent infection can be examined. such a model system is described in this paper. highly ... | 1999 | 10518541 |
| contribution of endothelin-1 to myocardial injury in a murine model of myocarditis: acute effects of bosentan, an endothelin receptor antagonist. | endothelin (et) is one of the most important contributing factors in the pathophysiology of cardiovascular diseases. however, little is known about its role in myocarditis. | 1999 | 10534471 |
| hepatitis c virus ns5a protein inhibits interferon antiviral activity, but the effects do not correlate with clinical response. | patients with chronic hepatitis c virus infection are commonly treated with interferon alfa (ifn-alpha), but the long-term response rate is poor. a region of ns5a of hepatitis c virus genotype 1 (the isdr) has been associated with treatment outcome in some patients. ns5a binds to and inhibits pkr in vitro and inhibits ifn-alpha in human cells. we examined the effects of the ns5a protein from patients who did or did not respond to ifn-alpha to determine whether ns5a from ifn-alpha nonresponders i ... | 1999 | 10535883 |
| specific interaction of a 25-kilodalton cellular protein, a 40s ribosomal subunit protein, with the internal ribosome entry site of hepatitis c virus genome. | translation initiation of hepatitis c virus (hcv) rna is controlled by an internal ribosome entry site (ires) contained in 5' noncoding region (ncr) and in several nucleotides of the coding region. the ability of a 25-kilodalton cellular protein (p25) to bind the hcv 5' ncr is correlated with the efficiency of translation initiation of hcv rna, indicating that this protein plays a critical role in hcv translation (s. fukushi, c. kurihara, n. ishiyama, f. b. hoshino, a. oya, and k. katayama, j vi ... | 1999 | 10541019 |
| apoptosis in congestive heart failure induced by viral myocarditis in mice. | it has recently been speculated that progressive deterioration of left ventricular function in chronic heart failure is due to the ongoing loss of viable cardiac myocytes. however, as there is little direct evidence of significant apoptosis contributing to the pathogenesis in cardiac myocytes in vivo, the significance of apoptosis in heart failure remains to be clarified. we investigated the role of apoptosis in heart failure induced by encephalomyocarditis virus myocarditis. dba/2 mice were ino ... | 1999 | 10543311 |
| expression of heterologous genes from an ires translational cassette in replication competent murine leukemia virus vectors. | we describe replication competent retroviruses capable of expressing heterologous genes during multiple rounds of infection. an internal ribosome entry site (ires) from encephalomyocarditis virus was inserted in the u3 region of akv- and sl3-3-murine leukemia viruses (mlv) to direct translation of neo or the enhanced green fluorescence protein gene (egfp). akv-mlv's with ires-neo and ires-egfp cassettes replicated with titers of about 10(6) infectious units/ml while sl3-3-mlv with ires-neo gave ... | 1999 | 10548723 |
| interaction of hepatitis c virus core protein with viral sense rna and suppression of its translation. | to clarify the binding properties of hepatitis c virus (hcv) core protein and its viral rna for the encapsidation, morphogenesis, and replication of hcv, the specific interaction of hcv core protein with its genomic rna synthesized in vitro was examined in an in vivo system. the positive-sense rna from the 5' end to nucleotide (nt) 2327, which covers the 5' untranslated region (5'utr) and a part of the coding region of hcv structural proteins, interacted with hcv core protein, while no interacti ... | 1999 | 10559281 |
| baculovirus stimulates antiviral effects in mammalian cells. | herein, we report that autographa californica nucleopolyhedrovirus, a member of the baculoviridae family, is capable of stimulating antiviral activity in mammalian cells. baculoviruses are not pathogenic to mammalian cells. nevertheless, live baculovirus is shown here to induce interferons (ifn) from murine and human cell lines and induces in vivo protection of mice from encephalomyocarditis virus infection. monoclonal antibodies specific for the baculovirus envelope gp67 neutralize baculovirus- ... | 1999 | 10559307 |
| la protein is required for efficient translation driven by encephalomyocarditis virus internal ribosomal entry site. | translation of internal ribosomal entry site (ires)-dependent mrnas is mediated by rna-binding proteins as well as canonical translation factors. in order to elucidate the roles of rna-binding proteins in ires-dependent translation, the role of polypyrimidine tract-binding protein (ptb) and la protein in encephalomyocarditis virus (emcv) ires-dependent translation was investigated. ptb was required for efficient emcv ires-driven translation but, intriguingly, an excess of ptb suppressed it. such ... | 1999 | 10567647 |
| dimerization of the interferon type i receptor ifnar2-2 is sufficient for induction of interferon effector genes but not for full antiviral activity. | we constructed chimeric receptors wherein the extracellular domain of the erythropoietin receptor (epor) was fused to the transmembrane and intracellular domains of the interferon (ifn) type i receptor subunits, ifnar1 or ifnar2-2. transfection into 2ftgh and tyk2-deficient 11,1 cells showed that epor/ifnar2-2 alone was able to transduce a signal upon stimulation with erythropoietin (epo), as judged by induction of the interferon type i-inducible 6-16 promoter. in contrast, protection against in ... | 1999 | 10574956 |
| the optimal use of ires (internal ribosome entry site) in expression vectors. | in higher eucaryotes, natural bicistronic mrna have been rarely found so far. the second cistron of constructed bicistronic mrnas is generally considered as not translated unless special sequences named internal ribosome entry site (ires) are added between the two cistrons. these sequences are believed to recruit ribosomes independently of a cap structure. in the present report, a new ires found in the htlv-1 genome is described. a systematic study revealed that this ires, but also the polioviru ... | 1999 | 10596757 |