Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| antibody response in baboons (papio cynocephalus anubis) to a commercially available encephalomyocarditis virus vaccine. | 1998 | 10090069 | |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| structural and functional differences between glycosylated and non-glycosylated forms of human interferon-beta (ifn-beta). | two recombinant ifn-beta products have been approved for the treatment of multiple sclerosis, a glycosylated form with the predicted natural amino acid sequence (ifn-beta-1a) and a non-glycosylated form that has a met-1 deletion and a cys-17 to ser mutation (ifn-beta-1b). the structural basis for activity differences between ifn-beta-1a and ifn-beta-1b, is determined. | 1998 | 9587963 |
| type i interferons are essential mediators of apoptotic death in virally infected cells. | the interferons (ifns) have been extensively studied in the context of host defence against viral infection. in the established model of ifn action, virally infected cells secrete type i ifns (ifn-alpha/beta) which induce an antiviral state in uninfected cells. however, it is not clear how ifns function on the infected cells. it has been reported that cells infected by some viruses die by apoptosis. | 1998 | 9581980 |
| determination of encephalomyocarditis viral diabetogenicity by a putative binding site of the viral capsid protein. | the molecular mechanism by which some, but not all, variants of encephalomyocarditis (emc) virus selectively infect pancreatic beta-cells in mice and induce iddm has been an enigma for more than a decade. we report here that the binding site of the emc viral capsid protein vp1 determines viral diabetogenicity. recombinant chimeric emc viruses containing threonine, serine, proline, aspartic acid, or valine at position 152 of the major capsid protein vp1 bind poorly to beta-cells. in contrast, rec ... | 1998 | 9568690 |
| evolution of a common structural core in the internal ribosome entry sites of picornavirus. | the translational control involving internal ribosome binding occurs in poliovirus (pv), human rhinoviruses (hrv), encephalomyocarditis virus (emcv), foot-and-mouth disease virus (fmdv), and hepatitis a virus (hav). internal ribosome binding utilizes cis-acting genetic elements of approximately 450 nucleotides (nt) termed the internal ribosome entry sites (ires) found in these picornaviral 5'-untranslated region (5'utr). although these ires elements are quite different in their primary sequence, ... | 1998 | 9562889 |
| combination of ok432 and human interferon-alpha for treating viral-induced diabetes mellitus in mice. | we investigated the therapeutic effects of ok432 (picibanil; cas39325-1-4), an immunomodulator that is derived from the su strain of streptococcus pyogenes. this agent was administered alone or combined with human interferon-alpha in a murine model of insulin-dependent diabetes mellitus. interferon-alpha inhibits viral replication, reducing the incidence of virus-induced iddm. groups of dba/2 mice (n = 25 per group) received an intraperitoneal injection of ok432 and interferon-alpha daily for 16 ... | 1998 | 9548400 |
| effects of intranasal administration of recombinant murine interferon-gamma on murine acute myocarditis caused by encephalomyocarditis virus. | viral myocarditis has been strongly implicated in the pathogenesis of dilated cardiomyopathy as well as acute myocarditis. among the antiviral therapies, interferons (ifns) have been widely studied and become very important in clinical practice. | 1998 | 9529271 |
| rnase l mediates the antiviral effect of interferon through a selective reduction in viral rna during encephalomyocarditis virus infection. | the 2',5'-oligoadenylate (2-5a) system is an rna degradation pathway which plays an important role in the antipicornavirus effects of interferon (ifn). rnase l, the terminal component of the 2-5a system, is thought to mediate this antiviral activity through the degradation of viral rna; however, the capacity of rnase l to selectively target viral rna has not been carefully examined in intact cells. therefore, the mechanism of rnase l-mediated antiviral activity was investigated following encepha ... | 1998 | 9525594 |
| protective effects of mu-fang-ji-tang against myocardial injury in a murine model of congestive heart failure induced by viral myocarditis. | the effects of mu-fang-ji-tang (tj-36), a traditional chinese herbal medicine, were studied in a murine model of congestive heart failure induced by viral myocarditis. in the group of animals treated with mu-fang-ji-tang in a dose of 1.5g/kg/day, the heart weight to body weight ratio was significantly lower than in the control group (p<0.01). histopathological grades were also significantly lower in the mu-fang-ji-tang treated group than in the placebo group (p<0.05). furthermore, survival was i ... | 1998 | 9519794 |
| co-expression of human adenosine deaminase and multidrug resistance using a bicistronic retroviral vector. | current gene therapy protocols designed to treat adenosine deaminase (ada) deficiency and other metabolic disorders suffer from low-efficiency delivery to target cells and a lack of long-term stability in expression of the therapeutic proteins. these problems may be resolved by use of an in vivo dominant selection. the multidrug transporter (mdr1) has been suggested as a useful selective marker for gene therapy. in this work, we co-expressed ada and mdr1 cdna in a retroviral vector using an inte ... | 1998 | 9508046 |
| interferon has no protective effect during acute or persistent reovirus infection of mouse sc1 fibroblasts. | mouse sc1 fibroblasts can support reovirus multiplication although they exhibit a partial resistance to viral-induced cytopathology; a significant percentage of infected sc1 cells can remain viable while becoming persistently infected by the virus. in the present study, the possible role of interferon on the fate of reovirus-infected cells was investigated. treatment of mouse l fibroblasts with beta-interferon resulted in a reduced viral efficiency of plating while essentially no effect was obse ... | 1997 | 9498612 |
| calcium channel blocker-induced protection against cardiovascular damage. | the therapeutic effects of calcium channel blockers on heart failure are controversial. however, a recent clinical trial demonstrated a favorable effect of amlodipine on survival rates in patients with heart failure resulting from nonischemic dilated cardiomyopathy. there are a number of studies showing that cytokines generated by activated immune cells cause an increase in nitric oxide (no) via induction of no synthase (nos), which results in a direct negative inotropic effect and a modulation ... | 1997 | 9488194 |
| antibodies against emc virus rna-vpg recognize tyr-(5'p-->o)-pu and immunostain infected cells. | covalent complexes of nucleic acids and proteins are widespread among viruses. covalent complexes of rna and proteins are proposed to exist in eukaryotic cells. the goal of this work was to obtain specific antibodies to the covalent linkage unit (clu) between virus rna and protein to search cellular rna-protein complexes. antibodies were generated by direct immunization of a rabbit with the bsa-coupled emc virus rna-vpg complex. by a dot-blot immunoassay and immunofluorescent microscopy it was f ... | 1998 | 9475169 |
| the use of cytokine inhibitors. a new therapeutic insight into heart failure. | cytokines are being increasingly recognized as important factors in the pathogenesis and pathophysiology of heart failure. elevated levels of circulating cytokines have been reported in patients with heart failure, and various cytokines have been shown to depress myocardial contractility in vitro and in vivo. we have recently compared the effects on cytokine production of drugs for therapy of heart failure that have different effects on survival. amrinone, pimobendan and vesnarinone, phosphodies ... | 1997 | 9464576 |
| the polyoma virus t antigen interferes with interferon-inducible gene expression. | murine polyoma virus (mpyv) is a small dna virus that induces tumors in multiple tissues of infected host. in this investigation, we show that cell lines derived from wild type virus-induced breast tumors are resistant to the growth inhibitory action of interferon beta (ifn-beta). furthermore, replication of heterologous viruses such as vesicular stomatitis virus and encephalomyocarditis virus was not inhibited by ifn-beta in these cells. this effect was due to inhibition of ifn-stimulated gene ... | 1998 | 9448289 |
| resistance to virus infection conferred by the interferon-induced promyelocytic leukemia protein. | the interferon (ifn)-induced promyelocytic leukemia (pml) protein is specifically associated with nuclear bodies (nbs) whose functions are yet unknown. two of the nb-associated proteins, pml and sp100, are induced by ifn. here we show that overexpression of pml and not sp100 induces resistance to infections by vesicular stomatitis virus (vsv) (a rhabdovirus) and influenza a virus (an orthomyxovirus) but not by encephalomyocarditis virus (a picornavirus). inhibition of viral multiplication was de ... | 1998 | 9444998 |
| high-level expression of exogenous genes by replication-competent retrovirus vectors with an internal ribosomal entry site. | we report the construction of two types of rous sarcoma virus (rsv)-based replication-competent avian retrovirus vectors, ir1 and ir2 to express an exogenous gene at a very high level. in these vectors, the internal ribosomal entry site (ires) derived from encephalomyocarditis virus (emcv) was inserted between the env gene and an exogenous gene. the ir1 vector retains the splicing acceptor site that is present in the downstream of the env gene while the ir2 vector lacks it. using a v-fos mutant ... | 1997 | 9427541 |
| total number and size distribution of motor neurons in the spinal cord of normal and emc-virus infected mice--a stereological study. | the encephalomyocarditis virus of the diabetogenic m-strain (emc-m) is known to cause diabetes in mice. the emc-m virus has also been shown to cause paresis in some of the infected animals. the clinical features include an acute ascending predominantly motor paralysis, developing within days. this resembles acute idiopathic polyneuritis. the alpha motor neurons would be a possible target for the virus, so two parameters, the total number and the size distribution of motor neurons, were therefore ... | 1997 | 9418991 |
| the internal ribosomal entry site of the encephalomyocarditis virus enables reliable coexpression of two transgenes in human primary t lymphocytes. | it is essential for the improvement of adoptive cell therapies to generate efficiently large populations of human primary t cells that reliably express a suicide gene conferring drug sensitivity, such as herpes simplex virus thymidine kinase (hsvtk). we show here that an optimized dicistronic vector containing the encephalomyocarditis virus (emcv) internal ribosomal entry site (ires) is functional in human primary. t lymphocytes that bear on average one integrated vector copy per cell. we demons ... | 1997 | 9415319 |
| isolation of a measles virus variant: protection of newborn mice from measles encephalitis by 24 h prior intracerebral inoculation with the variant. | a small plaque mutant with reduced neurovirulence in newborn mice was obtained from edmonston strain measles virus after propagation for 5 months in nih3t3 cells. it retained the antigenicity of the parental virus and tended to induce higher neutralizing antibody titers in the adult balb/c mice. the intracerebral (but not intraperitoneal) inoculation of the live mutant virus one day before prevented the newborn balb/c mice from encephalitis caused by the intracerebral challenge with the parental ... | 1997 | 9413503 |
| protective immunity against heterologous challenge with encephalomyocarditis virus by vp1 dna vaccination: effect of coinjection with a granulocyte-macrophage colony stimulating factor gene. | for dna vaccination studies, recombinant vp1 protein of encephalomyocarditis virus (emcv) was produced from escherichia coli, and eukaryotic vp1 expression vector, pct-gs-vp1, was generated and used as a dna vaccine. mice were immunized intramuscularly (i.m.) with pct-gs-vp1 in the presence or absence of plasmid dna expressing granulocyte-macrophage colony stimulating factor (gm-csf), and were subsequently analyzed for their anti-vp1 immune responses with recombinant vp1 in elisa. immunization o ... | 1997 | 9413089 |
| [serologic studies of domestic cats for potential human pathogenic virus infections from wild rodents]. | for several viral infections a reservoir in wild rodents has been demonstrated. some of the agents are known or suspected to be pathogenic for humans. because improvements in hygiene have reduced direct human contact with rodents, domestic cats could be acting as active transmitters of these viruses from rodents to man. we selected 4 such pathogens--ortho- and parapox-, hanta- and encephalomyocarditis viruses--which, in different ways, may lead to serious human illness: ortho- and parapoxvirus i ... | 1996 | 9409901 |
| effects of levamisole, an immunomodulator, upon murine encephalomyocarditis virus myocarditis. | to test the therapeutic efficacy of levamisole, 5-week-old dba/2 mice were inoculated intraperitoneally with 10 plaque-forming units of encephalo-myocarditis virus. levamisole (2.5 mg/kg/per day) was administered intraperitoneally daily, starting simultaneously with the virus inoculation, in experiment i for 14 days, and daily on days 14 to 28 in experiment ii in mice that survived to 14 days after virus inoculation. in experiment i, survival was higher, the severity of myocarditis was less, and ... | 1997 | 9403310 |
| retroviral transfer of herpes simplex virus-thymidine kinase and beta-galactosidase genes into u937 cells with bicistronic vector. | in this study we describe a new retroviral vector utilizing an internal ribosome entry site (ires) from encephalomyocarditis virus to co-express two genes. one is the herpes simplex virus type 1 thymidine kinase gene (hsv-tk) which induces sensitivity to ganciclovir, and the second is the bacterial beta-galactosidase gene (lacz) which was revealed by an histochemical staining with 5-bromo-4-chloro-3-indolyl-beta-d-galactopyranoside (x-gal). we engineered the u937 human cell line to co-express bo ... | 1997 | 9403006 |
| expression of a recombinant monoclonal antibody from a bicistronic mrna. | the variable regions of the murine monoclonal antibody a1, which effectively neutralizes the infection of susceptible cells by the murine hepatitis virus strain jhm, were cloned, sequenced, and expressed in mammalian cells as a functional recombinant antibody. to accomplish the concurrent synthesis of both antibody chains, the light- and heavy-chain-coding regions were inserted into a bicistronic expression cassette based on the encephalomyocarditis virus internal ribosomal entry site. the strat ... | 1997 | 9388025 |
| dicistronic lacz and alkaline phosphatase reporter constructs permit simultaneous histological analysis of expression from multiple transgenes. | we report here the development of convenient dicistronic transgenic markers for the rapid and efficient simultaneous analysis of transgene activity in transgenic mice. two sensitive histological markers, the beta-galactosidase (beta-gal)-encoding lacz gene and the human placental alkaline phosphatase (hpap) gene, have been fused to the internal ribosome entry sequence (ires) from the encephalomyocarditis virus, which directs efficient mrna cap-independent entry of the translation apparatus in ma ... | 1997 | 9383553 |
| a novel dicistronic aav vector using a short ires segment derived from hepatitis c virus genome. | adeno-associated virus (aav) vectors have a limited capacity for packaging dna. to insert both a therapeutic gene and a selectable marker gene in the same aav vector efficiently, we developed a novel dicistronic aav vector containing a 230 base pairs (bp) internal ribosome entry site (ires) element derived from hepatitis c virus (hcv) genome and a 420 bp blasticidin s-resistance gene (bsr) as a small selectable marker in the second cistron. the 650 bp hcv ires-bsr construct was placed downstream ... | 1997 | 9373150 |
| gain or loss of diabetogenicity resulting from a single point mutation in recombinant encephalomyocarditis virus. | molecular pathogenic mechanisms for virus-induced disease have received considerable attention. encephalomyocarditis (emc) virus-induced diabetes in mice has been extensively studied to elucidate the cellular and molecular mechanisms involved in the development of this disease. in this study, we report for the first time that a single point mutation at nucleotide position 3155 or 3156 of the recombinant emc viral genome, located on the major capsid protein vp1, which causes an amino acid change, ... | 1997 | 9371645 |
| pharmacological biocompatibility between intravesical preparations of bcg and interferon-alpha 2b. | to determine if bcg and interferon alpha-2b are mutually compatible as mixed intravesical agents for clinical bladder cancer therapy. | 1997 | 9366382 |
| efficient long-term coexpression of a hammerhead ribozyme targeted to the u5 region of hiv-1 ltr by linkage to the multidrug-resistance gene. | ribozymes as anti-hiv-1 agents hold promise for the treatment of aids. they can be delivered into cells either exogenously or through an expression system. for effective protection against hiv-1, sufficient and sustained amounts of the antiviral ribozymes must be delivered into target cells. the coexpression of a dominant selectable marker with ribozymes would serve to enrich for cells containing the molecular antiviral and facilitate prolonged expression of these ribozymes. the multidrug resist ... | 1997 | 9361910 |
| interferon action and apoptosis are defective in mice devoid of 2',5'-oligoadenylate-dependent rnase l. | 2',5'-oligoadenylate-dependent rnase l functions in the interferon-inducible, rna decay pathway known as the 2-5a system. to determine the physiological roles of the 2-5a system, mice were generated with a targeted disruption of the rnase l gene. the antiviral effect of interferon alpha was impaired in rnase l-/- mice providing the first evidence that the 2-5a system functions as an antiviral pathway in animals. in addition, remarkably enlarged thymuses in the rnase l-/- mice resulted from a sup ... | 1997 | 9351818 |
| adenovirus infection inactivates the translational inhibitors 4e-bp1 and 4e-bp2. | infection with many viruses results in the selective shutoff of host protein synthesis. a common target for virus interference with host protein synthesis is the cap-binding protein complex, eif4f. the large subunit of the complex, eif4g, is cleaved upon picornavirus (except cardiovirus) infection. infection with adenovirus and influenza virus causes dephosphorylation of the cap-binding subunit, eif4e. recently, it has been shown that infection with poliovirus or encephalomyocarditis virus activ ... | 1997 | 9344920 |
| tetracycline-mediated suppression of gene expression with a new dicistronic retroviral vector. | since the first description of the helper-free retrovirus vector by mann et al. (1983), many improvements have been introduced to the system to increase titer, or to achieve better expression of the transduced genes in cells of different lineage. the typical form of recombinant retrovirus vector utilizes its 5' long terminal repeat (ltr) as a promoter unit for the transcription of the inserted gene(s), which allows only the constitutive expression of the inserted gene(s) in target cells. althoug ... | 1997 | 9339896 |
| dicistronic tagging of genes active in embryonic stem cells of mice. | a gene-trap vector, pwh14, has been developed to tag genes expressed in embryonic stem (es) cells of the mouse. the approach relies on the ability of the endogenous promoter to drive promoterless neo-ires-lacz construct producing a dicistronic mrna consisting of the neomycin-resistance (neo) gene and the beta-galactosidase gene sequence. the neo gene produces a chimeric protein with the truncated product of the tagged gene and serves as a selectable marker for an insertion into an expressed gene ... | 1997 | 9339894 |
| comparison of various expression plasmids for the induction of immune response by dna immunization. | intramuscular injection of plasmid dna is an efficient method to introduce a foreign gene into a live animal. we investigated several factors affecting the gene transfer efficiency and the following immune response by intramuscular injection of plasmid dna. when the strength of several highly efficient viral promoters was compared in muscle by using the chloramphenicol acetyltransferase (cat) gene as an indicator, cytomegalovirus (cmv) immediate early promoter was found to be stronger than any o ... | 1997 | 9339893 |
| improved ebv-based shuttle vector system: dicistronic mrna couples the synthesis of the epstein-barr nuclear antigen-1 protein to neomycin resistance. | use of ebv-based vector systems has been limited by the requirement to generate ebna+ cells which are 'permissive' for replication of an orip-vector. in current constructs, selectable marker and ebna-1 are not always co-expressed. this is a significant problem since the ebna-1 gene product can be toxic in some cell types and may be selected against. in this paper, we describe a gene construct that overcomes this limitation. we have exploited the piconaviral internal ribosome entry site to allow ... | 1997 | 9332352 |