| mutations that alter the activity of the rous sarcoma virus protease. | mutations designed by analysis of the rous sarcoma virus (rsv) and human immunodeficiency virus (hiv)-1 protease (pr) crystal structures were introduced into 1) the substrate binding pocket, 2) the substrate enclosing "flaps," and 3) surface loops of rsv pr. each mutant pr was expressed in escherichia coli. changes in activity were detected by following cleavage of a truncated (nc-pr) precursor polypeptide in e. coli and cleavage of synthetic peptide substrates representing rsv and hiv-1 pr clea ... | 1992 | 1315755 |
| analysis of substrate interactions of the rous sarcoma virus wild type and mutant proteases and human immunodeficiency virus-1 protease using a set of systematically altered peptide substrates. | in the preceding study, mutant rous sarcoma virus (rsv) proteases are described in which three amino acids found in the human immunodeficiency virus-1 (hiv-1) protease (pr) were substituted into structurally comparable positions (grinde, b., cameron, c.e., leis, j., weber, i., wlodawer, a., burstein, h., bizub, d., and skalka, a. m. (1992) j. biol. chem. 267, 9481-9490). in this report, the activity of the wild type and these mutant prs are compared using a set of rsv nc-pr peptide substrates wi ... | 1992 | 1315756 |
| the effect of tyrosine-specific protein phosphorylation on the assembly of adherens-type junctions. | adherens-type junctions (ajs) are major subcellular targets for tyrosine specific protein phosphorylation [volberg et al. (1991) cell regul., 2, 105-120]. here we report on the apparent effect of such phosphorylation events on the assembly and integrity of ajs. we show that incubation of mdck cells with potent inhibitors of tyrosine-specific phosphatases (ptp), namely h2o2 and vanadate, leads to a dramatic increase in aj-associated phosphotyrosine which was apparent already within 2-5 min of tre ... | 1992 | 1316270 |
| biology of rous sarcoma virus adapted for replication and transformation of duck cells. | a duck-adapted variant of the prague strain of rous sarcoma virus and its molecularly cloned derivatives were characterized biologically. the virus replicated and transformed with the same efficiency both duck and chicken embryo fibroblasts. the dapr-rsv-c was also used for induction of tumours in newborn hamsters. the virus from virogenic hamster tumours could be rescued using the duck cells as indicator cells. the virus rescue was influenced by restricted replication of the virus in the indica ... | 1992 | 1317804 |
| gene transfer in primary cultures of human hepatocytes. | using liposomes as the mediator of dna transfer, we were successful in the transfection of human hepatocytes isolated from surgical samples with an e. coli beta-galactosidase gene (beta-gal). a comparison of transfection efficiency showed that of the four promoters used, cytomegalovirus (cmv) promoter yielded higher transfection efficiencies than rous sarcoma virus (rsv), simian virus-40 (sv-40) and human alpha-1 antitrypsin (aat) promoters. these studies represent the first report on the succes ... | 1992 | 1317838 |
| resistance of in vivo-selected spontaneously transformed cells and rous sarcoma virus-transformed cells to macrophage-mediated cytotoxicity. | the cytotoxic activity (cta) of activated peritoneal macrophages (mp) on variant lines of syrian hamster embryo (he) cells of differing malignant characteristics was studied. the target cells were a line of low-malignant cells resulting from spontaneous transformation of he cells in vitro (sthe strain), and malignant variants selected from them in vivo (sthe-lm-4, sthe-lm-8, and sthe-75/18 strains). in addition, we used cells of the het-sr-1 strain; these are he cells transformed in vitro by a t ... | 1992 | 1318222 |
| bovine respiratory syncytial virus fusion protein gene: sequence analysis of cdna and expression using a baculovirus vector. | the nucleotide sequence of bovine respiratory syncytial virus (rsv), atcc strain a51908 fusion (f) glycoprotein gene cdna was determined. the amino acid sequence deduced was then compared to those of two different isolates of bovine rsv, strains rb 94 and 391-2, and the a and b subtypes of human rsv, strains 18537 and a2. the bovine rsv f protein is highly conserved between the three isolates, a51908 has 97% amino acid identity to rb 94, and 99% identity to 391-2. the f proteins of both the a an ... | 1992 | 1318950 |
| protein and lipid lateral diffusion in normal and rous sarcoma virus transformed chick embryo fibroblasts. | we measured the lateral diffusion of the fluorescent lipid analogue dioctadecylindocarbocyanine iodide (dii) and of membrane glycoproteins labeled with tetramethylrhodamine (tritc) succinyl concanavalin a (scona) via fluorescence photobleaching recovery (fpr) at selected times during a temperature downshift experiment on transformation-defective temperature-sensitive (td-ts) rous sarcoma virus (rsv) ny68-transformed chicken embryo fibroblasts (cef) and on identically treated cef and rsv-transfor ... | 1992 | 1319742 |
| infection of terminally differentiated myotubes with rous sarcoma virus (rsv): lack of dna integration but presence of rsv mrna. | we re-examined the generally accepted concept that replication of rous sarcoma virus (rsv) requires host dna synthesis. we used terminally differentiated chicken myotubes as the host because chromosomal dna replication is completely abolished by the natural differentiation process. southern blot analysis detected unintegrated viral dna in both the nucleus and cytoplasm of infected myotubes. this indicated that reverse transcription of the infecting viral rna and transport of the newly synthesize ... | 1992 | 1321212 |
| infection of terminally differentiated myotubes with rous sarcoma virus: reduced synthesis of env and v-src proteins. | we studied rous sarcoma virus (rsv) protein synthesis in rsv-infected, terminally differentiated chicken myotubes ('late-infected' myotubes), in which no viral dna integration takes place but all three viral mrnas (38s, 28s and 21s) are transcribed normally. with the use of specific anti-rsv protein antisera, we found that only the viral gag and pol proteins were synthesized at levels similar to those synthesized in rsv-transformed fibroblasts; the synthesis of env and v-src proteins was signifi ... | 1992 | 1321213 |
| transforming properties and substrate specificities of the protein tyrosine kinase oncogenes ros and src and their recombinants. | to determine the sequences of the oncogenes src (encoded by rous sarcoma virus [rsv]) and ros (encoded by ur2) that are responsible for causing different transformation phenotypes and to correlate those sequences with differences in substrate recognition, we constructed recombinants of the two transforming protein tyrosine kinases (ptks) and studied their biological and biochemical properties. a recombinant with a 5' end from src and a 3' end from ros, called src x ros, transformed chicken embry ... | 1992 | 1321277 |
| unmutated proto-src coding region is tumorigenic if expressed from the promoter of rous sarcoma virus: implications for the gene-mutation hypothesis of cancer. | the transforming (onc) genes of oncogenic retroviruses share most or all of their coding sequences with normal cellular genes termed proto-onc genes. the viral genes differ from proto-onc genes in virus-specific promoters and in various point mutations and substitutions of cell-derived coding regions. in view of the structural similarities between viral oncogenes and cellular proto-onc genes, the hypothesis has been advanced that proto-onc genes become cellular cancer genes if they have suffered ... | 1992 | 1321438 |
| methylations of 70,000-da heat shock proteins in 3t3 cells: alterations by arsenite treatment, by different stages of growth and by virus transformation. | we have characterized the basic amino acid methylation of three members of the 70,000-da heat shock protein superfamily, hsp68, hsc70, and bip, in balb/c 3t3 cells. it appears that a lysyl residue is the only methylation site in bip and that both lysyl and arginyl residues are methylated in hsp68 and hsc70. in all cases, epsilon-n-trimethyllysine is the predominant methyllysine species. both ng-monomethylarginine and ng,ng-dimethylarginine are identified as the methylarginine species. the stoich ... | 1992 | 1322111 |
| small deletion in v-src sh3 domain of a transformation defective mutant of rous sarcoma virus restores wild type transforming properties. | rsv mutant virus pa101t was obtained while assaying the tumorigenicity of parental pa101 virus in chickens. pa101 is a transformation defective mutant of rsv which has a low src kinase activity. however, pa101 retained a temperature-sensitive ability to induce sustained proliferation of neuroretina cells. pa101t appeared as a wild-type phenotype revertant of pa101. molecular cloning and sequencing of pa101t showed that this reversion is due to additional mutations in pa101 src gene. these mutati ... | 1992 | 1322589 |
| transformation of chicken myelomonocytic cells by a retrovirus expressing the v-myb oncogene from the long terminal repeats of avian myeloblastosis virus but not rous sarcoma virus. | to test the effect of long terminal repeat (ltr) regulatory sequences on the transforming capability of the v-myb oncogene from avian myeloblastosis virus (amv), we have constructed replication-competent avian retroviral vectors with nearly identical structural genes that express v-myb from either amv or rous sarcoma virus (rsv) ltrs. after transfection into chicken embryo fibroblasts, virus-containing cell supernatants were used to infect chicken myelomonocytic target cells from preparations of ... | 1992 | 1323701 |
| activation of human eosinophils in vitro by respiratory syncytial virus. | to determine the nature of the interaction between viruses and eosinophils, normodense eosinophils were separated from the blood of healthy volunteers and incubated in vitro with respiratory syncytial virus (rsv). after incubation for 2 h with the virus, 29.5 +/- 15.8% of the eosinophils demonstrated specific binding of the virus to the cell membrane, as detected by fluorescent staining with an anti-rsv mab. superoxide production and leukotriene c4 release were measured as determinants of cell a ... | 1992 | 1324464 |
| microinjection of cloned proviral rous sarcoma virus dnas into xenopus laevis one cell embryos. | plasmid patv8 carrying rous sarcoma virus (rsv) dna with one long terminal repeat (ltr) or plasmid paprc carrying complete rsv proviral dna was injected into fertilized eggs of xenopus laevis. the fate of the exogenous dnas was followed during embryogenesis. in both cases a new form of dna, comigrating with endogenous dna, began to appear shortly after the injection. this new form represented a linear dimer of the injected plasmid that had formed by ligation of linear monomers of the plasmid dna ... | 1992 | 1326446 |
| partial characterization of rat cell lines infected by a rous sarcoma virus-33. | rous sarcoma virus-33 (rsv-33) was obtained from a sample of chicken rous sarcoma which had been dried and stored in 1933. rsv-33, like the rsv-29, has the minimal number of passages beyond its isolation from chicken tumour no. 1. our experiments demonstrated that the rous sarcoma virus-33 was replication non-defective and was pathogenic for rats. established rat tumorigenic cell lines express the viral genome. all three species of viral rna were detected and v-src proteins and gag polyproteins ... | 1992 | 1326448 |
| differentiation of quail myoblasts transformed with a temperature sensitive mutant of rous sarcoma virus. ii. relationship of myoblast fusion with calcium and temperature. | the effects of calcium and temperature on fusion of quail embryonic myoblasts were examined using cells transformed with a temperature-sensitive mutant of rous sarcoma virus (ts-rsv). the transformed quail myoblasts (qm-rsv) fused to form myotubes at 41 degrees c, the non-permissive temperature, but not at 35.5 degrees c, the permissive temperature. on incubation at 41 degrees c, a period of more than 10 hr was needed for the myoblasts to become fusion-competent, but calcium was not needed for d ... | 1992 | 1327546 |
| role of the open reading frames of rous sarcoma virus leader rna in translation and genome packaging. | the rous sarcoma virus (rsv) rna leader sequence carries three open reading frames (uorfs) upstream of the aug initiator of the gag gene. we studied, in vivo, the role of these uorfs by changing two or three nucleotides of the three augs or by deleting the first uorf. our results show that (i) unlike most previously characterized uorfs, which decrease translation, the first uorf (aug1) of rsv acts as an enhancer of translation, since absence of the first aug decreased translation; aug3 also modu ... | 1992 | 1327749 |
| treatment of acute pulmonary failure with extracorporeal support: 100% survival in a pediatric population. | since february 1990, five children, aged 10 days to 6.5 years, were treated with extracorporeal lung support at our hospital for acute, unrelenting pulmonary failure. two had viral pneumonia: one with respiratory syncytial virus (rsv) bronchiolitis, and one with herpes simplex virus pneumonia, encephalitis, and disseminated intravascular coagulation. one presented with a febrile illness followed by a pulmonary hemorrhage. two patients had adult respiratory distress syndrome (ards) complicating s ... | 1992 | 1328587 |
| transformation of nih3t3 cells by rous sarcoma virus occurs with high efficiency in the absence of proviral rearrangements or amplification. | nih3t3 cells could be transformed by a mammaltropic strain of rous sarcoma virus (rsv) with an efficiency 10(3) times greater than that observed in balb/c 3t3 cells or other mammalian cell lines and almost identical to that of chick embryo fibroblasts. in infected nih3t3 cells a single, properly integrated, provirus was sufficient to induce focus formation; moreover, kinase activity of pp60v-src and tyrosine phosphorylation of cellular proteins could be detected very soon after infection in the ... | 1992 | 1328985 |
| major histocompatibility (b) complex control of the growth pattern of v-src dna-induced primary tumors. | observations that the major histocompatibility (b) complex is a determinant of the growth pattern of rous sarcoma virus (rsv)-induced tumors raised the question as to whether control is exerted at the level of a v-src-determined, i.e., transformation-specific, function. to investigate this point, the tumor size scores and tumor profile indices of v-src-induced tumors were compared in two lines of chickens congenic for b complex genotypes. the finding that the growth patterns of tumors, induced b ... | 1992 | 1329333 |
| the mannose-specific plant lectins from cymbidium hybrid and epipactis helleborine and the (n-acetylglucosamine)n-specific plant lectin from urtica dioica are potent and selective inhibitors of human immunodeficiency virus and cytomegalovirus replication in vitro. | a series of four mannose(man)-, three n-acetylglucosamine (glcnac)n-, ten n-acetylgalactosamine/galactose(galnac/gal)-, one 5-acetylneuraminic acid (alpha-2,3-gal/galnac)- and one 5-acetylneuroaminic acid(alpha-2,6-gal/gal-nac)-specific plant agglutinins were evaluated for their antiviral activity in vitro. the mannose-specific lectins from the orchid species cymbidium hybrid (ca), epipactis helleborine (eha) and listera ovata (loa) were highly inhibitory to human immunodeficiency virus type 1 ( ... | 1992 | 1329650 |
| mechanism of inhibition of the retroviral protease by a rous sarcoma virus peptide substrate representing the cleavage site between the gag p2 and p10 proteins. | the activity of the avian myeloblastosis virus (amv) or the human immunodeficiency virus type 1 (hiv-1) protease on peptide substrates which represent cleavage sites found in the gag and gag-pol polyproteins of rous sarcoma virus (rsv) and hiv-1 has been analyzed. each protease efficiently processed cleavage site substrates found in their cognate polyprotein precursors. additionally, in some instances heterologous activity was detected. the catalytic efficiency of the rsv protease on cognate sub ... | 1992 | 1331099 |
| enhanced detection of respiratory viruses using the shell vial technique and monoclonal antibodies. | the shell vial technique using a549 and mdck cells, coupled with the use of bartels respiratory viral monoclonal antibodies, was evaluated initially for the detection of 28 previously isolated respiratory viruses. all viruses were recovered and correctly identified. the shell vial-monoclonal antibody technique was then evaluated for virus isolation from 338 respiratory specimens and compared with the conventional tube method. both methods gave rise to a total of 83 virus isolates. of these isola ... | 1992 | 1331151 |
| host range of rous sarcoma virus pseudotype rsv(hprs-103) in 12 avian species: support for a new avian retrovirus envelope subgroup, designated j. | the host ranges of the rous sarcoma virus (rsv) pseudotype rsv(hprs-103) of a novel avian leukosis virus (alv), strain hprs-103, and representative rsv pseudotypes of subgroups a to f, have been determined in embryo fibroblasts from 12 avian species. domestic fowl, red jungle fowl, sonnerat's jungle fowl and turkey were susceptible to infection by rsv(hprs-103); ring-necked pheasant, japanese green pheasant, golden pheasant, japanese quail, guinea-fowl, peking duck, muscovy duck and goose were r ... | 1992 | 1331300 |
| a chimeric avian retrovirus containing the influenza virus hemagglutinin gene has an expanded host range. | we have investigated what protein sequences are necessary for glycoprotein incorporation into rous sarcoma virus (rsv) virions by utilizing the hemagglutinin (ha) protein of influenza virus. two chimeric ha genes were constructed. in the first the coding sequence for the signal peptide of the rsv env gene product was fused in frame to the entire ha structural gene, and in the second the hydrophobic anchor and cytoplasmic domain sequences of the ha gene were also replaced with those from the rsv ... | 1992 | 1331528 |
| structural studies of the retroviral proteinase from avian myeloblastosis associated virus. | the structure of the retroviral proteinase from avian myeloblastosis associated virus (mav) has been determined and refined at 2.2 a resolution. this structure is compared with those of homologous proteinases from rous sarcoma virus (rsv) and human immunodeficiency type 1 virus (hiv). through comparison with the structure of a proteinase-inhibitor complex from hiv, a model of a complex between mav proteinase and a peptide substrate has been generated. examination of this model suggests structura ... | 1992 | 1332025 |
| rapid detection of respiratory viruses using mixtures of monoclonal antibodies on shell vial cultures. | eleven hundred and thirty-three clinical specimens submitted to the laboratory for diagnosis of respiratory virus infections were tested by direct immunofluorescence (dif) for respiratory syncytial virus (rsv), by shell vial culture, and by conventional cell culture. the shell vial cultures were stained with 8 different monoclonal antibodies both 1 day and 3-7 days after inoculation. in order to limit the cost and the workload, mixtures of monoclonal antibodies were used. coverslips with hep-2 c ... | 1992 | 1334129 |
| rous sarcoma virus does not induce sarcoma in early chick embryos by lack of the v-src gene expression. | the schmidt-ruppin or the b77 strain of rous sarcoma virus (rsv) was inoculated into limb buds of 4.5-days-old avian embryos. no sarcoma but blister formation was observed in those rsv-inoculated embryos. protein kinase activity of pp60v-src in rsv-inoculated embryos, even in the site of virus inoculation, was the same as that in mock-infected embryos. this indicated that the expression of the v-src gene did not attain superiority over that of the c-src gene in rsv-inoculated embryos. the v-src ... | 1992 | 1336425 |
| [intravenous gamma globulins (i.v.ig) in the treatment and prevention of virus infections]. | active research is currently underway to determine the role of intravenous administration of igg (i.v.ig) in preventing and treating viral infections (cmv, hiv, rsv, eb, echo, adeno). these studies strongly suggest that immunoglobulin therapy may be beneficial in renal and bone marrow transplant patients to prevent or treat in cmv infections. intravenous gamma globulins appears to be effective not only reducing the overall prevalence of coronary artery abnormalities in kawasaki disease but, more ... | 1992 | 1338350 |
| tumor induction by the ltr, v-src, ltr dna in four b (mhc) congenic lines of chickens. | we report that the cloned dna harboring the long terminal repeat (ltr), v-src, ltr proviral structure is tumorigenic in chickens of the prague congenic lines. the growth rate of these tumors is by far the highest in the recombinant cc.r1 line, the b haplotype of which is composed of the b-f/l4 and b-g12 subregions originating from different naturally occurring haplotypes. some of the tumors induced by the ltr, v-src, ltr dna are repeatedly transplantable in syngeneic chickens, maintain unaltered ... | 1992 | 1348493 |
| prospective controlled study of four infection-control procedures to prevent nosocomial infection with respiratory syncytial virus. | to determine the most effective infection control procedure in preventing nosocomial infection with respiratory syncytial virus (rsv), we did a prospective controlled study of four infection-control strategies in four wards in a large paediatric hospital in the west of scotland. all children under two years old admitted to four general wards during three winter rsv epidemics (1989-92) were screened for rsv infection (by nasopharyngeal aspirate and direct immunofluorescence) within 18 hours of ad ... | 1992 | 1357462 |
| reshaping a human monoclonal antibody to inhibit human respiratory syncytial virus infection in vivo. | we transferred the complementarity determining regions from a murine monoclonal antibody that neutralizes infection by respiratory syncytial virus (rsv) to a human igg1 monoclonal antibody. the resulting reshaped human antibody lost affinity for rsv, but an additional alteration to one of the framework regions restored binding affinity and specificity. this second generation reshaped human monoclonal antibody cross-reacted with all clinical isolates of rsv tested and both prevented disease and c ... | 1991 | 1367535 |
| rapid detection of respiratory viruses by shell vial culture and direct staining by using pooled and individual monoclonal antibodies. | the bartels respiratory virus panel detection kit is an indirect fluorescent-antibody (ifa) method that uses pooled and individual antisera for tissue culture confirmation of seven respiratory viruses. we evaluated these reagents for detecting viral antigen in shell vial cultures and by direct staining of cells from respiratory specimens. the isolation from 254 specimens of respiratory viruses in shell vial cultures compared with standard tube cultures was highly sensitive (94%) and specific (97 ... | 1992 | 1372616 |
| infectious respiratory syncytial virus (rsv) effectively inhibits the proliferative t cell response to inactivated rsv in vitro. | the effect of respiratory syncytial virus (rsv) on the cellular immune response of human mononuclear cells in vitro was examined. inhibition by rsv of the lymphocyte response to phytohemagglutinin in vitro was confirmed using cells from human umbilical cord blood. in addition, rsv significantly inhibited both the proliferative and t cell colony responses of human mononuclear cells to epstein-barr virus. an rsv-specific cellular immune response was induced in vitro by stimulation of mononuclear c ... | 1992 | 1373752 |
| rapid detection of respiratory syncytial virus in nasopharyngeal aspirates by reverse transcription and polymerase chain reaction amplification. | a rapid method for detection of respiratory syncytial virus (rsv) in nasopharyngeal aspirates, involving a combination of reverse transcription and polymerase chain reaction amplification (rt-pcr), has been developed. the rt-pcr assay employs oligonucleotide primers specific for the region of the rsv genome which encodes the f1 subunit of the fusion (f) glycoprotein. other respiratory viruses do not give a positive reaction. the rt-pcr assay was tested on 202 nasopharyngeal aspirates collected f ... | 1992 | 1374080 |
| intracellular processing of the human respiratory syncytial virus fusion glycoprotein: amino acid substitutions affecting folding, transport and cleavage. | the intracellular processing and transport of the respiratory syncytial virus (rsv) fusion (f) glycoprotein was examined by comparing the maturation and stability of wild-type f, uncleaved mutant f and chimeric f glycoproteins expressed by recombinant vaccinia viruses to that of f protein expressed by rsv. one of the recombinant viruses, vf317, expressed f protein (f317) that was processed like the rsv f glycoprotein. f317 was synthesized initially as f0, the uncleaved glycosylated precursor of ... | 1992 | 1375280 |
| cloning and characterization of a thermolabile v-src gene for use in reversible transformation of mammalian cells. | the use of temperature-sensitive (ts) src mutants for studies of cell transformation and differentiation has been limited by the availability of cloned ts-src genes that are inactivated at temperatures compatible with growth of mammalian cells. in this report, we describe the cloning and characterization of the tsla90src gene, which displays tight thermal sensitivity at 39.5 degrees c. nucleotide sequence comparison of tsla90 and wild-type src genes from the schmidt-ruppin subgroup a and d strai ... | 1992 | 1375718 |
| expression of the human cystic fibrosis transmembrane conductance regulator gene in the mouse lung after in vivo intratracheal plasmid-mediated gene transfer. | as an approach to gene therapy for the respiratory manifestations of cystic fibrosis (cf), in vivo plasmid-mediated direct transfer of the normal cf transmembrane conductance regulator (cftr) gene to the airway epithelium was investigated in mice. to evaluate the feasibility of this strategy, prsvl, a plasmid composed of a firefly luciferase gene driven by the rous sarcoma virus long terminal repeat (rsv-ltr), along with cationic liposomes was instilled into the trachea of c57bi/6ncr mice. with ... | 1992 | 1377820 |
| specificity of rous sarcoma virus nucleocapsid protein in genomic rna packaging. | site-directed mutagenesis has shown that the nucleocapsid (nc) protein of rous sarcoma virus (rsv) is required for packaging and dimerization of viral rna. however, it has not been possible to demonstrate, in vivo or in vitro, specific binding of viral rna sequences by nc. to determine whether specific packaging of viral rna is mediated by nc in vivo, we have constructed rsv mutants carrying sequences of moloney murine leukemia virus (momulv). either the nc coding region alone, the psi rna packa ... | 1992 | 1378506 |
| nosocomial respiratory syncytial virus infection in a newborn nursery. | the nosocomial spread of respiratory syncytial virus (rsv) was studied in a newborn nursery in benin city, nigeria at a time the virus was known to be highly prevalent in the community. nasopharyngeal washings were obtained from babies on admission and, thereafter, every 4 days until discharged. questionnaires were administered to medical personnel with upper respiratory tract infection (urti). rsv was detected by an elisa technique. a total of 56 babies were studied, made up of 33 preterm and 2 ... | 1992 | 1381895 |
| differentiation of quail myoblasts transformed with a temperature sensitive mutant of rous sarcoma virus. i. relationship between differentiation and tyrosine kinase of src gene product. | quail embryonic pectoral myoblasts fuse with each other at 35.5 degrees c and 41 degrees c to essentially equal extents. when the myoblasts were transformed with a temperature-sensitive mutant of rous sarcoma virus (ts-rsv), their fusion and biochemical processes of differentiation became temperature-sensitive: their fusion occurred at 41 degrees c, the non-permissive temperature, but not at 35.5 degrees c, the permissive temperature, suggesting that the fusion was regulated by the viral transfo ... | 1992 | 1382873 |
| protective epitopes on the fusion protein of respiratory syncytial virus recognized by murine and bovine monoclonal antibodies. | the regions of the fusion protein of respiratory syncytial virus (rsv) that react with neutralizing, fusion-inhibiting and highly protective bovine and murine monoclonal antibodies (mabs) were mapped by two methods: (i) competitive binding assays and (ii) production and analysis of antibody-escape mutants. competitive binding assays with 16 murine and 10 bovine mabs identified 11 antigenic sites on the fusion (f) protein, many of which overlapped extensively, and indicated that cattle, a natural ... | 1992 | 1383403 |
| the p60c-src family of protein-tyrosine kinases: structure, regulation, and function. | in 1911, peyton rous reported that a fibrosarcoma could be transmitted between chickens in a cell-free extract of the tumor. the transmissible agent, rous sarcoma virus (rsv), transforms cells by virtue of the presence within its genome of a viral oncogene, v-src, which is derived from a normal cellular gene that has been picked up, or transduced, by the virus. this cellular proto-oncogene, c-src, encodes a protein, p60c-src, which has the ability to phosphorylate proteins on tyrosine residues. ... | 1992 | 1384720 |
| osteoclasts express high levels of p60c-src, preferentially on ruffled border membranes. | expression of p60c-src, the normal cellular counterpart of the transforming protein of rous sarcoma virus (rsv), p60v-src, was examined in mouse and rat authentic osteoclasts and mouse osteoclast-like multinucleated cells (mncs) formed in vitro. in co-cultures of mouse osteoblastic cells and spleen cells, the expression of p60c-src strikingly increased on day 5 in parallel with the appearance of mncs in the presence of 1 alpha,25-dihydroxyvitamin d3 (1 alpha,25(oh)2d3). immunohistochemical exami ... | 1992 | 1385221 |
| epitopes at the proteolytic cleavage sites of hiv-1-gp120 and rsv-f protein share a sequence homology: comparative studies with virus-induced and antipeptide antibodies. | the proteolytic cleavage sites of the human immunodeficiency virus type 1 (hiv-1) envelope glycoprotein precursor gp160 and the fusion protein of respiratory syncytial virus (rsv) show a sequence homology. to study this homology two synthetic peptides corresponding to hiv-1-env-gp160-aa 507-518 (kakrrvvqrekr) and rsv-f2-aa 130-136 (skkrkrr) were synthesized. human serum samples from hiv-positive or rsv-positive collections recognized the appropriate peptide in 90.6 or 37.2% respectively. no cros ... | 1992 | 1385356 |
| comparison of a new commercial enzyme immunoassay for rapid detection of respiratory syncytial virus. | two rapid methods for detection of respiratory syncytial virus in respiratory specimens were compared: direct immunofluorescence assay (dfa) with monoclonal antibody and an enzyme immunoassay (eia) (test-pack rsv). ninety-five nasopharyngeal washings and aspirates from 51 children were examined; the patients were hospitalized during a winter outbreak of rsv infection in the first trimester of 1990. a total of 41.0% and 56.8% of these samples were positive by eia and dfa respectively. considering ... | 1992 | 1396733 |
| transcription of human respiratory syncytial virus genome rna in vitro: requirement of cellular factor(s). | extracts made from human respiratory syncytial virus (rsv)-infected hep-2 cells synthesized mrnas encoded by all known viral genes. in contrast, rsv ribonucleoproteins purified from infected cells failed to transcribe in vitro; transcription was restored by addition of a cytoplasmic extract of uninfected hep-2 cells, demonstrating that a cellular factor(s) has a role in rsv gene expression. quantitation of the individual gene mrnas transcribed in vitro revealed polarity of transcription of the g ... | 1992 | 1404620 |
| genetically engineered rice resistant to rice stripe virus, an insect-transmitted virus. | the coat protein (cp) gene of rice stripe virus was introduced into two japonica varieties of rice by electroporation of protoplasts. the resultant transgenic plants expressed the cp at high levels (up to 0.5% of total soluble protein) and exhibited a significant level of resistance to virus infection. plants derived from selfed progeny of the primary transformants also expressed the cp and showed viral resistance, indicating stable transmission of the cp gene and the trait of resistance to the ... | 1992 | 1409714 |
| sero-epidemiological studies of respiratory syncytial and adenoviruses in children in ibadan, nigeria, 1985-1988. | retrospective and prospective serological surveys to determine the prevalence of respiratory syncytial virus (rsv) and adenovirus (adv) infections in children with respiratory diseases were carried out from 1985 to 1988 at the university college hospital, ibadan, nigeria. 306 sera from subjects between 3 months and 12 years old were assayed by complement fixation test for antibodies to both viruses. second samples were available from 42 of the subjects for antibody conversion testing. the rate v ... | 1992 | 1412660 |
| risks connected with the use of conventional and genetically engineered vaccines. | a review is given of real and potential risks connected with the use of conventional and genetically engineered live and dead vaccines. special attention is given to live carrier vaccines expressing one or more heterologous genes of other microorganisms. because most carrier vaccines are still in an experimental phase, there is only limited experience with the risks of carrier vaccines. there are three potential risks of live carrier vaccines which will be discussed: 1. changes in cell, tissue, ... | 1992 | 1413441 |
| immunologic response of adenoidal lymphocytes to respiratory syncytial virus. | adenoidal lymphocytes obtained from 43 subjects with serum antibodies to respiratory syncytial virus (rsv) were established in culture in vitro and analyzed for immunoglobulin (ig) and rsv-specific antibody synthesis. spontaneous synthesis of ig was consistently observed in culture supernatants. the ratios of iga to igg and igm to igg in adenoidal lymphocyte culture supernatant were higher than in serum. in cell cultures stimulated with rsv or pokeweed mitogen, rsv antibody activity was detected ... | 1992 | 1416640 |
| detection of genomic sequences of respiratory syncytial virus in otitis media with effusion in children. | the reverse transcriptase-polymerase chain reaction and the nested polymerase chain reaction were used for detection of respiratory syncytial virus (rsv) sequences in middle ear effusions collected from children with otitis media. sequences of rsv were detected in 21 of 34 samples tested. these samples were collected during and/or after natural outbreaks of rsv infection in the community. in those patients from whose nasopharynges rsv was isolated, the viral sequences were highly detectable (75% ... | 1992 | 1416657 |
| evaluation of three rapid enzyme immunoassays and cell culture for detection of respiratory syncytial virus. | three rapid enzyme immunoassay techniques for the detection of respiratory syncytial virus antigen (becton dickinson directigen rsv, abbott rsv testpack and abbott rsv eia) and cell culture were evaluated in a total of 250 nasal washings. the sensitivity and specificity were 62% and 76% respectively for directigen, 64% and 86% for rsv testpack, and 76% and 81% for rsv eia, taking cell culture as the reference method. agreement between cell culture and eia techniques was 79% (70 positive and 128 ... | 1992 | 1425717 |
| a novel, spectrophotometric microneutralization assay for respiratory syncytial virus. | we describe a simple and rapid microneutralization assay for respiratory syncytial virus (rsv) based on the colorimetric quantitation of the conversion of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (mtt) to a formazan product by the mitochondria of viable cells. conditions for rsv infectivity were first optimized for sensitivity and reproducibility based on cell density and on rsv concentration as a function of multiplicity of infection (moi) and time post-infection and the re ... | 1992 | 1430065 |
| immunotherapy of respiratory syncytial virus infection in cotton rats (sigmodon fulviventer) using igg in a small-particle aerosol. | to determine whether aerosolized igg can be used effectively in the treatment of respiratory syncytial virus (rsv) infections, cotton rats were infected intranasally with rsv and treated 3 days later with human igg containing anti-rsv antibodies delivered in a small-particle aerosol. pulmonary histology and virus titers were determined 24 h after igg treatment. a single 15-min exposure to aerosolized igg did not exacerbate pulmonary pathology and effected a 50-fold reduction in pulmonary virus t ... | 1992 | 1431258 |
| respiratory syncytial virus detection by dot blot hybridization with a nonradioactive synthetic oligo deoxynucleotide probe. | a synthetic oligodeoxynucleotide corresponding to a region of the nucleocapside gene (n) of respiratory syncytial virus (rsv), was used as a dna probe to develop a nonradioactive hybridization assay for the detection of rsv. the probe was labeled by incorporation of biotin-7-datp to the 3' end by a reaction catalyzed by terminal deoxynucleotydil transferase. the dot blot hybridization assay was found to be specific for rsv when tested against rsv isolates (subgroups a and b) obtained from cell c ... | 1992 | 1431818 |
| pulmonary histopathology induced by respiratory syncytial virus (rsv) challenge of formalin-inactivated rsv-immunized balb/c mice is abrogated by depletion of cd4+ t cells. | in previous studies, it was observed that children immunized with a formalin-inactivated respiratory syncytial virus vaccine (fi-rsv) developed severe pulmonary disease with greater frequency during subsequent natural rsv infection than did controls. during earlier efforts to develop an animal model of this phenomenon, enhanced pulmonary histopathology was observed after intranasal rsv challenge of fi-rsv-immunized cotton rats. progress in understanding the immunologic basis for these observatio ... | 1992 | 1433525 |
| intensive care course and outcome of patients infected with respiratory syncytial virus. | picu admissions of 97 children positive for respiratory syncytial virus on fluorescent antibody screening were reviewed; 68% of 44 patients without history of preceding disease (group i) and 79% of 53 patients with preceding pulmonary, cardiac, or other disease (group ii) required ventilation. in group i ventilated children weighted significantly less (p = 0.001) and were of lower chronological (p = 0.02) and post-conceptional ages (p = 0.02) than those not ventilated. eighteen infants ventilate ... | 1992 | 1437327 |
| the role of viruses and mycoplasma pneumoniae in lower respiratory tract infections in childhood. | acute lower respiratory tract infections are one of the major causes of childhood morbidity and mortality in developing countries. this study was undertaken at hacettepe university children's hospital to determine the role of viruses and mycoplasma pneumoniae in respiratory tract infections in children. eighty-three patients with lower respiratory tract infections were selected at random from among the children admitted to the hospital for evaluation of respiratory symptoms. acute and convalesce ... | 1992 | 1440953 |
| production and secretion of high levels of recombinant human acetylcholinesterase in cultured cell lines: microheterogeneity of the catalytic subunit. | to allow for structural analysis of the human acetylcholinesterase (hache) subunit, a series of eukaryotic vectors was designed for efficient expression. several eukaryotic multicistronic expression vectors were tested in various mammalian cell lines. all expression vectors contained the selectable neo gene under control of a weak promoter, while the hache cdna was under control of the cytomegalovirus (cmv) immediate-early or rous sarcoma virus long terminal repeat (rsv ltr) or simian virus 40 ( ... | 1992 | 1446827 |
| shedding of infectious virus and virus antigen during acute infection with respiratory syncytial virus. | shedding of respiratory syncytial virus (rsv) in nasopharyngeal aspirates (npa) of hospitalized children with acute respiratory infection was studied using direct antigen detection by time-resolved fluoroimmunoassay, rapid identification of infectious virus in centrifugally inoculated cell cultures by immunoperoxidase staining and conventional virus culture. sequential npas, in which also local rsv-specific iga response was measured, were collected from children with proven rsv infection. the sh ... | 1992 | 1460457 |
| a rearranged jund transforms chicken embryo fibroblasts. | a complementary dna clone synthesized from the chicken jund mrna, containing 5'- and 3'-untranslated sequences, was inserted in the retroviral expression vector rcas to yield the construct jd. a second rcas construct (dddd) contained only the coding domains of jund. dddd did not transform upon primary transfection, but jd produced small numbers of transformed cell foci in chicken embryo fibroblast cultures. the virus recovered from these foci, jdv, was moderately transforming for chicken fibrobl ... | 1992 | 1472471 |
| susceptibility to infection in relation to sids. | because there is little evidence that invasive bacterial diseases contribute to cot deaths, most studies on infectious causes of sids have focused on viruses or toxin producing bacteria. although epidemiological studies found marginally significant associations between influenza virus and sids, respiratory syncytial virus (rsv) was isolated from 90% of older infants with sids. there are conflicting reports that some toxigenic bacteria (clostridium botulinum, clostridium difficle, enterotoxigenic ... | 1992 | 1474153 |
| comparison of three immunoassays for the rapid detection of bovine respiratory syncytial virus. | three enzyme-linked immunosorbent assays (eia) designed for the detection of human respiratory syncytial virus (rsv) were evaluated for the detection of bovine respiratory syncytial virus (brsv) in bovine lungs and the results were compared with those obtained by a direct fluorescent antibody assay (dfa). the eia tests used were directigen eia, kallestad pathfinder eia, and abbott rsv eia. homogenates of lung tissues obtained from 64 cattle that had died of respiratory disease were used; 32 were ... | 1992 | 1501586 |
| synthesis and antiviral evaluation of n-carboxamidine-substituted analogues of 1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamidine hydrochloride. | ten, hitherto unreported, analogues of 1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamidine hydrochloride (2a, ribamidine) and methyl carboximidate 5 have been synthesized. these include the n-cyano (2b), n-alkyl (2c-e), n-amino acid (2f-h), n,n'-disubstituted (6, 7a,b), and the n-methylated carboxamide (1f) analogues of ribavirin. in addition, a new facile synthesis of carboxamidine 2a was also developed. all compounds were evaluated for biological activity against the following rna viruses: p ... | 1992 | 1507208 |
| evidence of immunosuppression by bovine respiratory syncytial virus. | respiratory syncytial virus (rsv) is a major respiratory pathogen in human infants and calves. calves and lambs infected with bovine rsv show mild clinical signs but they are more susceptible to secondary infection with pasteurella haemolytica. lambs infected with p. haemolytica 6 days after experimental infection with bovine rsv had significantly greater magnitudes of fever, higher disease and lesion scores and higher mortality rates than those infected with p. haemolytica or bovine rsv alone ( ... | 1992 | 1514055 |
| active respiratory syncytial virus purified by ion-exchange chromatography: characterization of binding and elution requirements. | two viruses, respiratory syncytial virus (rsv) and vesicular stomatitis virus (vsv) were used to evaluate viral purification by an affinity resin column (matrex cellufine sulfate (mcs); amicon division, wr grace & co.). viable rsv was purified significantly from crude cell lysate by a single pass through a column containing the anionic mcs resin. most cell protein and albumin eluted from the mcs resin with phosphate buffered saline (pbs) but rsv eluted at high ionic strength, i.e., greater than ... | 1992 | 1517352 |
| improved outcome of respiratory syncytial virus infection in a high-risk hospitalized population of canadian children. pediatric investigators collaborative network on infections in canada. | to determine the outcomes in children at high risk for death or complications from respiratory disease who are hospitalized with respiratory syncytial virus (rsv) infection. | 1992 | 1517907 |
| lack of effect of respiratory syncytial virus infection on theophylline disposition in children. | conflicting reports raise a question about decreased plasma clearance (clp) of theophylline in man during viral infections. thus a dilemma exists concerning requisite dose adjustments. we examined this issue by retrospectively evaluating theophylline clp in children infected with respiratory syncytial virus (rsv). two pharmacokinetic approaches were applied to a one-compartment open model to fit theophylline concentrations during 83 hospitalizations of 76 children, 6 to 48 months of age, who rec ... | 1992 | 1517927 |
| the limited role of the human interferon system response to respiratory syncytial virus challenge: analysis and comparison to influenza virus challenge. | the respiratory syncytial virus (rsv)-induced production of interferon (ifn) by human macrophages and mononuclear leukocytes (mnl) and the sensitivities of rsv to subtypes of ifn-alpha were examined and compared to ifn production induced by influenza virus. influenza virus induced high titers of total ifn bioactivity, transcription of the ifn-alpha 1 and ifn-beta gene products and production of ifn-gamma. in contrast, rsv induced minimal or no detectable total ifn activity, and the absence of if ... | 1992 | 1522795 |
| respiratory syncytial virus: a comparison of diagnostic modalities. | this study compared prospectively viral culture for respiratory syncytial virus (rsv) with three rapid rsv antigen detection tests: rsv eia and testpack rsv (tp), and directigen rsv (dir). additionally two methods of specimen collection were compared: nasopharyngeal rub (rub) and nasopharyngeal wash (wash). true positives were defined as positive rsv viral culture or at least two positive antigen tests. one hundred ninety-eight wash specimens obtained from children 3 years of age or younger duri ... | 1992 | 1523070 |
| immunogenicity of recombinant adenovirus-respiratory syncytial virus vaccines with adenovirus types 4, 5, and 7 vectors in dogs and a chimpanzee. | recombinant adenovirus type 4, 5, and 7 expressing the fusion glycoprotein (f) gene, the attachment glycoprotein (g) gene, or both f and g genes of respiratory syncytial virus (rsv) was constructed. intratracheal immunization of dogs with ad7f induced moderate titers of rsv-neutralizing antibodies. after booster immunization with ad4f, the dogs developed high titers of rsv-specific antibody. subsequently, three two-dose vaccination regimens, ad4f/ad5f, ad7g/ad4g, and ad7fg/ad4fg, were compared w ... | 1992 | 1527411 |
| solubilization and promoter analysis of rna polymerase from rice stripe virus. | the rna-dependent rna polymerase associated with rice stripe virus was dissociated from viral rna (vrna) by cscl centrifugation. the solubilized rna-free rna polymerase transcribed a model rna template 50 nucleotides in length carrying the 5'- and 3'-terminal conserved sequences of all four genome rna segments. a 3'-terminal half molecule of the model template was also active as a template. hence, we propose that the 3'-terminal conserved sequence serves as a promoter for the rice stripe virus-a ... | 1992 | 1527854 |
| protective activity of a human respiratory syncytial virus immune globulin prepared from donors screened by microneutralization assay. | to explore the feasibility of preparing a human immune globulin specific for respiratory syncytial virus (rsv) by screening plasma donors, the ability of seven rsv antibody assays to identify plasma-yielding igg with high virus-neutralizing and animal-protective activities was compared. igg prepared from plasma units selected by microneutralization assay had significantly higher activity in protecting mice from respiratory rsv challenge than did iggs prepared from plasmas selected by three direc ... | 1992 | 1538152 |
| comparison of the ability of formalin-inactivated respiratory syncytial virus, immunopurified f, g and n proteins and cell lysate to enhance pulmonary changes in balb/c mice. | formalin-inactivated respiratory syncytial virus (fi-rsv), a lysate of hep-2 cells and proteins f, g and n, immunopurified from infected cell cultures, were compared for their ability to prevent infection and to enhance changes in lung cytology associated with rsv challenge. mice were immunized at three weekly intervals with serial dilutions of the preparations and challenged by the nasal route 1 week after the last injection; their lungs were analysed 4 days later. the concentration of the immu ... | 1992 | 1539464 |
| class-specific antibodies to bovine respiratory syncytial virus in experimentally infected lambs. | enzyme-linked immunoabsorbent assay (elisa) was used to titrate virus-specific igg, igm and iga levels in nasal secretions, lung lavage fluids and serum samples sequentially obtained from lambs experimentally infected with bovine respiratory syncytial virus (rsv). virus-specific igg and igm responses were measured by the indirect double antibody sandwich elisa using anti-bovine rsv monoclonal antibody, as capture antibody, and peroxidase-conjugated anti-sheep igg and anti-sheep igm. virus-specif ... | 1992 | 1547834 |
| transcriptional activation of the cef-4/9e3 cytokine gene by pp60v-src. | the cef-4/9e3 gene is expressed constitutively in rous sarcoma virus (rsv)-transformed cells. this expression is largely determined by an increase in transcription of the gene. in this report, we characterize the regulatory elements responsible for the transformation-dependent activation of cef-4/9e3. three sequences corresponding to ap-1, prd ii/kappa b, and taacgcaatt are involved in the process and therefore define the src-responsive unit (sru) of the cef-4 promoter. in constructs containing ... | 1992 | 1549106 |
| respiratory syncytial virus infection of human primary nasal and bronchial epithelial cell cultures and bronchoalveolar macrophages. | in adults, clinical symptoms caused by respiratory syncytial virus (rsv) are usually confined to the upper respiratory tract, whereas rsv infection in infants frequently causes bronchiolitis and pneumonia. the preferential localization of rsv infection to the upper airways may partially be due to protective immunity, but may also depend on a difference in susceptibility of epithelial cells from upper and lower airways, or on antiviral activities of bronchoalveolar macrophages (am). in this study ... | 1992 | 1550681 |
| reinfection of lambs with bovine respiratory syncytial virus. | eight lambs which were experimentally infected with bovine respiratory syncytial virus (rsv) when they were six to eight weeks old were challenged with the same virus seven months later. after reinfection, lambs developed mild clinical disease and the virus was isolated from nasal swabs from three lambs and peripheral blood from two lambs. reinfection resulted in changes in peripheral blood cell populations. there was an early increase in the number of cd8+ t lymphocytes and b (lca p220+) lympho ... | 1992 | 1553439 |
| respiratory syncytial virus infection of alveolar macrophages in adult transplant patients. | pulmonary epithelial cells are thought to be the primary cellular targets for infection by respiratory syncytial virus (rsv) in vivo. to determine whether other pulmonary cells are infected by rsv, bronchoalveolar lavage cells from six adult transplant patients, four of whom had acute rsv infection, were examined by in situ immunohistochemistry to identify infected lung cells. both alveolar macrophages and epithelial cells were infected with rsv in vivo. at the single-cell level, three-color imm ... | 1992 | 1554223 |
| mucosal t cell distribution during infection with respiratory syncytial virus. | groups of 12-week-old balb/c mice were inoculated intranasally with respiratory syncytial virus (rsv) and sacrificed at regular intervals after infection. t lymphocyte subset distribution was determined in lung tissue, bronchoalveolar lavage (bal), peripheral blood, and spleen by means of flow cytometry employing monoclonal antibodies against the t cell membrane antigens thy1.2 (pan-t), ly2 (cd8), and l3t4 (cd4). thy1.2+ cells increased in the lung from 35.4% of total lymphocytes before infectio ... | 1992 | 1564449 |
| respiratory syncytial virus: a pediatric nursing plan of care. | thirty-three pediatric cases of respiratory syncytial viral (rsv) infections were treated at providence hospital's pediatric intensive care unit (picu), anchorage, ak, between september 1987 and march 1988. our 8-bed picu nursing and respiratory therapy staff learned effective techniques in caring for patients with rsv. our aim in this article is to share our approach in providing comprehensive care for patients with rsv infections. | 1992 | 1569520 |
| respiratory syncytial virus infection reinforces reflex apnea in young lambs. | to evaluate the effect of respiratory syncytial virus (rsv) infection on reflex apnea elicited by application of water on the laryngeal mucosa, 11 healthy, term lambs were chronically instrumented at 2 wk of age. six lambs were inoculated with bovine rsv, and five lambs were mock-infected. the lambs were studied awake and unsedated before and 4, 8, 14, and 21 d after infection. rsv infection was associated with slight rhinorrhea and with moderately increased tracheal mucous discharge. there was ... | 1992 | 1570205 |
| severe respiratory syncytial virus pneumonia after autologous bone marrow transplantation: a report of three cases and review. | three patients with acute leukemia who underwent autologous bone marrow transplantation (bmt) in complete remission, developed a severe respiratory syncytial virus (rsv) pneumonia, which was fatal in two. identification of rsv was made on the products of bronchoalveolar lavage by direct immunofluorescence. as already described by others, the initial course of rsv infection varies, depending on whether it occurs sooner or later after bmt with a better prognosis in the latter situation. treatment ... | 1992 | 1571714 |
| gene transfer into specific vascular cells. | gene transfer therapy in vascular surgery is on the horizon and will include the insertion of genes for anti-clotting proteins into the endothelial lining of vascular grafts and for genes controlling the proliferation of smooth muscle cells after endovascular intervention. here we address the possibility of targeting genes to specific vascular cells using non-infectious methods, deae-dextran or lipofectin complexes of reporter genes, to aid transfection of endothelial cells, smooth muscle cells ... | 1992 | 1572452 |
| humoral immunity to respiratory syncytial virus infection in the elderly. | the relationship between serum immunoglobulins and the severity and risk of respiratory syncytial virus (rsv) infection in the institutionalized elderly was prospectively assessed during the winter of 1989-1990 at a 591 bed nursing home. forty rsv infections were identified out of 149 respiratory illnesses by isolation of the virus or by a greater than or equal to 4-fold rise in rsv-specific igg by eia. acute serum rsv igg levels were similar in those with rsv infection and those with non-rsv il ... | 1992 | 1573388 |
| an outbreak of respiratory syncytial virus in a bone marrow transplant center. | an outbreak of respiratory syncytial virus (rsv) infection occurred among 31 patients in a marrow transplant center over a 13-week period beginning in january 1990. rsv infection was also documented in 35 family members and employees. of 18 patients with pneumonia, 14 (78%) died. none of 13 with upper respiratory infection died. preengraftment patients tended to develop pneumonia more frequently than did engrafted patients. early administration of ribavirin may have had a beneficial effect in pa ... | 1992 | 1583345 |
| viruses as precipitants of asthma symptoms. i. epidemiology. | the epidemiological studies cited have indicated that viruses are commonly associated with wheezing illnesses in populations, in individuals, and in time, but, unlike bacteria, are rarely found during asymptomatic periods. viruses have been identified in up to 50% of wheezing illnesses and asthma exacerbations occurring in childhood, and in up to 20% of those in adults. in childhood the predominant organisms identified have been rhinoviruses. rsv and parainfluenza viruses, but coronaviruses have ... | 1992 | 1586873 |
| complete nucleotide sequence of rna 4 of rice stripe virus isolate t, and comparison with another isolate and with maize stripe virus. | the complete nucleotide sequence of rna 4 of rice stripe virus isolate t (rsv-t) was determined and found to consist of 2157 nucleotides, containing two open reading frames (orfs). one, deduced to be present in the 5'-proximal region of the viral-sense rna, encodes the stripe disease-specific protein with mr 20541, and the other orf, in the 5'-proximal region of the viral complementary sense rna, encodes an unknown protein with mr 32474. between these two orfs there is an intergenic non-coding r ... | 1992 | 1588328 |
| effect of respiratory syncytial virus on adherence, colonization and immunity of non-typable haemophilus influenzae: implications for otitis media. | adherence of non-typable haemophilus influenzae to respiratory epithelium was evaluated in a cotton rat model of respiratory syncytial virus (rsv) infection. colonization with non-typable h. influenzae increased to a maximum within 4 days of rsv infection compared to rsv negative controls (4.58 +/- 0.17 vs 3.82 +/- 0.23 log colony forming units (cfu) per ml, p less than 0.05) and then declined over the subsequent 10 days (2.0 +/- 0 vs 3.78 +/- 0.39 cfu per ml, p less than 0.0001). in a second se ... | 1992 | 1592548 |
| successful therapy with ribavirin of late onset respiratory syncytial virus pneumonitis complicating allogeneic bone transplantation. | a 21-year-old patient developed interstitial pneumonitis nine months post bone marrow transplant for acute myeloblastic leukaemia. immunofluorescence of broncheoalveolar lavage fluid revealed the presence of respiratory syncytial virus (rsv). aerosolized ribavarin therapy resulted in rapid resolution of the pneumonitis with full recovery without any side effects. ribavarin therapy should be considered early in the management of bmt patients who develop rsv pneumonitis. | 1992 | 1600691 |
| respiratory syncytial virus infection in an adult with wegener's granulomatosis. | respiratory syncytial virus (rsv) has been documented as a pathogen in adults who are immunocompromised because of various underlying conditions. to our knowledge, this is the first report of a patient with wegener's granulomatosis (wg) and rsv infection resulting in a fatal outcome. | 1992 | 1600799 |
| summertime respiratory syncytial virus infection: epidemiology and clinical manifestations. | respiratory syncytial virus (rsv) is a common serious pathogen known to produce annual winter epidemics in young children. a 2-year study of children with significant respiratory disease during the summer revealed a 21% incidence of rsv infection. respiratory secretions collected from ill children in the lsumc outpatient clinics, from children seen by private physicians, and from children hospitalized with respiratory tract disease were assayed for rsv antigens. approximately 39% of those survey ... | 1992 | 1604385 |
| [epidemiology of respiratory syncytial virus infections in the canary islands]. | respiratory syncytial virus (rsv) is the major cause of lower respiratory tract infection in young children. outbreaks of rsv infection occur yearly during the winter or spring in temperate climates. our study of 634 hospitalized children under 3 years of age with bronchiolitis and pneumonia (november 1988 to january 1990) revealed that 227 (35.8%) had vrs infections. these cases showed a yearly epidemic pattern with 86.8% of the cases occurring during the winter. furthermore, 67.4% of the cases ... | 1992 | 1605415 |
| cotton rats previously immunized with a chimeric rsv fg glycoprotein develop enhanced pulmonary pathology when infected with rsv, a phenomenon not encountered following immunization with vaccinia--rsv recombinants or rsv. | in studies conducted in the 1960s, children previously immunized with a formalin-inactivated respiratory syncytial virus (rsv) vaccine (fi-rsv) developed a greater incidence and severity of pulmonary disease during subsequent natural rsv infection than did controls. it was previously shown that cotton rats immunized with fi-rsv or immunoaffinity-purified fusion (f) glycoprotein developed enhanced pulmonary histopathology following intranasal challenge with rsv. in the present studies, various fo ... | 1992 | 1609551 |
| the ras and protein kinase a pathways are mutually antagonistic in regulating rat prolactin promoter activity. | in an attempt to characterize the ras signaling pathway, we studied the effects of expression vectors encoding the valine 12 mutant ras oncogene on rat prolactin (rprl) promoter activity. using this approach we have been able to dissect the interplay between the ras and the protein kinase a (pka) pathways as they relate to neuroendocrine gene activation. here we show that the ras oncogene product induces rprl promoter activity selectively from 5- to 14-fold in gh4 rat pituitary tumor cells, wher ... | 1992 | 1620544 |
| recent observations regarding the pathogenesis of recurrent respiratory syncytial virus infections: implications for vaccine development. | respiratory syncytial virus (rsv) and influenza virus are common pathogens for all age groups. currently licensed influenza virus vaccines generally provide protection from clinically detectable disease caused by antigenically matched challenging viruses. in contrast, vaccine development for rsv has been hampered by the inability of candidate vaccines to induce protective immunity to naturally occurring infection. the precise mechanism(s) responsible for the rsv vaccine failures have not been de ... | 1992 | 1621415 |