| the leader sequence of the subgenomic mrna's of rous sarcoma virus is approximately 390 nucleotides. | the subgenomic mrna's of rous sarcoma virus share a common 5' leader sequence spliced from genomic rna. we have examined the 5' terminal sequences of four rous sarcoma virus rnas: virion rna and three species of intracellular mrna which direct the synthesis of the rsv gene products. the lengths of the leaders on the rnas were determined by the extent that they could protect cloned rous sarcoma virus dna fragments from s1 nuclease digestion after rna-dna hybridization. we found that the subgenomi ... | 1982 | 6281464 |
| rous sarcoma virus transformed cells are resistant to cyclic amp. | a nontransformed line of chinese hamster ovary (cho) cells (pollard and stanners, 1979) has been transformed by the schmidt-ruppin subgroup d strain of rous sarcoma virus (sr-rsv). sr-rsv transformed cho cells are shown to differ from spontaneously transformed cells in that the virally transformed cells are more resistant to growth inhibition or changes in cell shape by 8-br-cyclic amp or cholera toxin. sr-rsv transformed rat (nrk) cells also have a reduced sensitivity to growth inhibition by 8- ... | 1982 | 6282904 |
| the role of respiratory syncytial virus and other viral pathogens in acute otitis media. | we utilized recently developed enzyme immunoassay techniques to examine the role of selected viruses in the etiology of acute otitis media. viral pathogens were found in middle ear fluids obtained from 13 (24%) of 53 children with acute otitis media; respiratory syncytial virus accounted for ten of the 13 viral agents identified. in addition, respiratory syncytial viral antigen was found in nasopharyngeal washings obtained from 15 of the 53 children. seven of these children had rsv identified as ... | 1982 | 6283052 |
| complementation of major histocompatibility haplotypes in regression of rous sarcoma virus-induced tumors in noninbred chickens. | relative responses to rous sarcoma virus (rsv)-induced tumors were studied in unh 105 chickens, a noninbred line of new hampshires. a total of 799 chickens blood typed for b alloantigens were classified into six genotypes: b23/b23, b24/b24, b26/b26, b23/b24, b23/b26, and b24/b26. chickens were inoculated with subgroup a rous sarcoma virus in the left wingweb at 6 weeks of age. the in vivo response was evaluated and given a tumor profile index (tpi) based on the change in tumor size over a 10-wee ... | 1982 | 6283511 |
| the increase in hormone-stimulated adenylate cyclase activity following rous sarcoma virus transformation. | rous sarcoma virus (rsv)-infected chicken embryo cells were used to study the effect of viral transformation on the hormone-stimulated synthesis of cyclic amp. transformation by rsv greatly increased the cells' ability to synthesize and accumulate cyclic amp in response to the beta-adrenergic agonist isoproterenol as compared to untransformed cells. this enhancement was observed in both intact cells and in membranes prepared from these cells. the inclusion of guanosine 5'-0-(3-thiotriphosphate), ... | 1982 | 6284770 |
| adsorption of rous sarcoma virus to genetically susceptible and resistant chicken cells studied by laser flow cytometry. | quantitative binding of rous sarcoma virus (rsv) of different antigenic subgroups to chicken cells was examined by using a laser flow cytometer/cell sorter. rsv of subgroups a, c, and e, labeled with the fluorescent membrane probe rhodamine-18, bound 2 to 10 times more to genetically susceptible chicken embryo fibroblasts than to resistant cells, as measured by flow cytometry on a single-cell basis. this suggested that susceptible cells possess both specific and nonspecific receptors for virus a ... | 1982 | 6284984 |
| role of p60src kinase activity in the induction of neuroretinal cell proliferation by rous sarcoma virus. | expression of the src gene of rous sarcoma virus (rsv) in chicken embryo neuroretinal (nr) cells results in morphological transformation and sustained proliferation of a normally resting cell population. we have previously reported the isolation of mutants of rsv which retain full growth-promoting activity while displaying reduced transforming properties. two such mutants, pa101 and pa104, were used to investigate whether the p60src-associated kinase activity is required for the mitogenic functi ... | 1982 | 6284995 |
| major histocompatibility complex (b): effect on the response of chickens to a second challenge with rous sarcoma virus. | the influence of b genotype on the formation of a second rsv-induced tumor was studied. line 6(3) (b2/b2) and (6(1) x 15(1))f3 and f4 b2/b2 and b5/b5 chickens were challenged with rsv in the left wingweb at 6 weeks of age. tumor-bearing animals then were rechallenged with rsv in the right wingweb at either 10, 11, or 12 days post primary inoculation. most b2/b2 hosts resisted development of a second tumor compared to none of the b5/b5 hosts. failure of a second tumor to develop in b2/b2 hosts wa ... | 1982 | 6285325 |
| construction of plasmids for expression of rous sarcoma virus transforming protein, p60src, in escherichia coli. | we have constructed plasmids that direct the synthesis of the rous sarcoma virus transforming gene (src) product (p60src) in escherichia coli. a 203-base-pair lac promoter-operator dna encoding the first eight amino acids of beta-galactosidase was ligated to the 5' end of the src gene from the prague a strain of rous sarcoma virus (pra-rsv) which had been cloned in pbr325. antiserum, from a tumor-bearing rabbit, directed against pp60src was used to screen bacteria containing the recombinant plas ... | 1982 | 6285367 |
| transformation of chick embryo fibroblasts by rous sarcoma virus does not inhibit the assembly of fibronectin into reduction-sensitive dimer and high molecular weight complex. | chick embryo fibroblasts (cefs) transformed by rous sarcoma virus synthesize reduced amounts of fibronectin and also shed this protein into the medium more rapidly than do uninfected cells. we wanted to know whether or not the increased fibronectin shedding rate observed in rsv-transformed cefs could be explained by an inability of fibronectin to form dimers and/or hmw complex. our studies on normal and rsv-transformed fibroblasts labelled either metabolically or by lactoperoxidase-catalysed iod ... | 1982 | 6286256 |
| characterization of a mutant of the prague strain of rous sarcoma virus inducing fusiform transformation of avian fibroblasts in vitro. | the dna as isolated from duck fibroblasts transformed by a duck-adapted prague strain of rous sarcoma virus and used for transfection. transformed recipient blef and def cultures exhibited considerable morphological variability. the virus designated dapr-rsv-c morphf was obtained from the culture with fusiform transformation and cloned. the virus retained the ability to induce fusiform transformation, even after 20 passages on chicken fibroblasts. there was a good correlation between focus formi ... | 1982 | 6286373 |
| individually distinct tumor-specific cell surface antigen identified by monoclonal antibody on a rous sarcoma virus-induced mouse tumor. | hybrid cell lines were prepared by the fusion of balb/c myeloma p3u-1 cells with the lymphocytes of balb/c mice that were immunized with syngeneic rous sarcoma virus (rsv)-induced tumor csa1m cells. three clones of the hybrid progeny (3.4b2, 3.4c6, and 3.5c11) produced cytotoxic igm antibodies against csa1m cells. one of the clones, 3.5c11, was chosen for analysis of the detailed specificity. both direct cytotoxicity assays and absorption tests revealed that monoclonal antibody from 3.5c11 was p ... | 1982 | 6287079 |
| tyrosine phosphorylation of a 50k cellular polypeptide associated with the rous sarcoma virus transforming protein pp60src. | we have examined the phosphorylation of a 50,000-dalton cellular polypeptide associated with the rous sarcoma virus (fsv) transforming protein pp60-src. it has been shown that pp60src forms a complex with two cellular polypeptides, an 89,000-dalton heat-shock protein (89k) and a 50,000-dalton phosphoprotein (50k). the pp60src-associated protein kinase activity phosphorylates at tyrosine residues, and the 50k polypeptide present in the complex contains phosphotyrosine and phosphoserine. these obs ... | 1982 | 6287229 |
| phosphorylations of the subcellular matrix in cells transformed by rous' sarcoma virus. | the transforming protein of rous' sarcoma virus (rsv) is a phosphoprotein of mr 60 000 (pp60src) which displays protein kinase activity specific for tyrosine residues; pp60src is associated with the plasma membrane and is recovered in the detergent-insoluble material which represents the subcellular matrix of the cell. after phosphorylation of this material of rsv-transformed cells with [gamma-32p]atp, five phosphoproteins have been detected which are not seen in normal cells. these proteins (mr ... | 1982 | 6288376 |
| effect of reduction of culture medium sodium, using different sodium chloride substitutes, on the proliferation of normal and rous sarcoma virus-infected chicken fibroblasts. | we have substituted choline chloride, tetramethylammonium chloride, sucrose, or glucose for culture medium sodium chloride. when culture medium sodium is reduced below physiological levels (143 mm) by replacement of graded concentrations of sodium chloride with equivalent concentrations of choline chloride, normal fibroblasts approach proliferative inactivity in the presence of 90 mm na, while their rous sarcoma virus (rsv)-infected counterparts proliferate actively; both normal and neoplastic c ... | 1982 | 6288744 |
| immunologic response in chickens from different genetic lines to rous sarcoma virus. | twelve young chickens of the tumor progressor and tumor regressor lines were studied in respect to their humoral immunologic response to challenge with rous sarcoma virus via inoculation into the wing web. on day 1, prior to virus inoculation and on days 10, 15, and 20 after injection of virus, the birds were bled and their serums tested for the presence of anti-rsv factors by standard procedures of serum-neutralization tests. from the conducting of statistical analyses of the data, it was deter ... | 1982 | 6290063 |
| isolation of high and low molecular weight components from chicken sera that have rous sarcoma virus neutralizing activity. | blood sera components from arkansas regressor line (r-line) and progressor line (pr-line) chickens are compared for the first time for rous sarcoma virus neutralizing activity. sera was fractionated by sephadex g-100 filtration into a high molecular weight fraction i (hmw-i) and a low molecular weight fraction ii (lmw-ii) component (hmw-i greater than 14,000 daltons, lmw-ii less than 5,000 daltons). both fractions from each line of chickens exhibit activity against rous sarcoma virus (rsv) judge ... | 1982 | 6291019 |
| immunofluorescent localization of the transforming protein of rous sarcoma virus with antibodies against a synthetic src peptide. | antisera were raised against a synthetic peptide (src-c) containing the six cooh-terminal amino acids of p60src, the transforming protein of rous sarcoma virus (rsv). antibodies specific for the src-c peptide were purified by affinity chromatography and then used to study the location of p60src in transformed cells. the distribution of p60src was compared to that of vinculin, a candidate cytoskeletal substrate of p60src, by indirect double immunofluorescence microscopy. in rsv-transformed rat, m ... | 1982 | 6291037 |
| failure to confirm the role of immunological tolerance to b (mhc) alloantigens in the growth of rsv-induced tumours in chickens. | chickens of the inbred "regressor" line cb (b12/b12) were made tolerant to the b13 (mhc) alloantigen of the congenic "progressor" line cc and then challenged with prague strain of rous sarcoma virus of subgroup c. no changes in tumour growth between tolerant and control groups were observed. these results suggest that there is no cross-reactivity between b13 alloantigen and rsv-induced tumour antigens. | 1982 | 6292007 |
| isolation of the homogeneous constituents from non-diffusible sugar-peptide (nsp) fraction originating from bovine plasma--ii. the influence on cell growth of bhk-21, bhk/rsv and pr-rsh cells in vitro. | 1. the sugar-peptide aggregate isolated from the nsp fraction of bovine blood, added in concentration 20 microgram/ml, decrease of [3h]thymidine incorporation and cell proliferation of bhk-21 and bhk/rsv cells in vitro to approx. 25% of untreated control. 2. two of four peptide constituents of the aggregate show distinct and extremely different effects on cell growth in vitro. the effects of peptide d mol. wt 5000-6000 is characteristic for peptide growth factors, while the peptide g mol. wt 120 ... | 1982 | 6292017 |
| microfilaments associated with paget's disease of bone: comparison with nucleocapsids of measles virus and respiratory syncytial virus. | the structural characteristics and intracellular disposition of microtubules present in osteoclasts in paget's disease of bone were compared with those of nucleocapsids in cells infected with measles virus and respiratory syncytial virus (rsv). the distribution of microtubules in pagetic osteoclasts closely paralleled that of measles nucleocapsids in monkey kidney cells, but the dimensions of the pagetic microtubules were significantly different from those of measles virus. in contrast, pagetic ... | 1982 | 6292129 |
| determination of infectivity of transforming avian sarcoma virus and parotitis virus in fibrin-embedded monolayer cultures. | a sensitive and reproducible technique for titration of transforming avian sarcoma virus, rous sarcoma virus (rsv), in chick embryo cell monolayers embedded between two layers of a solid fibrin coagulum was developed. the foci of rsv-transformed fibrinolysis-exhibiting cells locally attacked the surrounding fibrin and were identifiable as plaque-like cell-free areas of retraction easily scored against the background of cells stained with neutral red. in comparison to the conventional assay in ag ... | 1982 | 6292249 |
| monoclonal antibody specific for avian sarcoma virus structural protein p27. | a hybridoma cell line which secretes antibody to the rous sarcoma virus (rsv) structural protein p27 has been established. the hybrid resulted from the fusion of ns-1 myeloma cells with spleen cells from a balb/c mouse which was immunized with rsv-transformed mouse cells. antibodies produced by the hybrid clone immunoprecipitated p27 and gag precursor proteins (pr180gag,pol, pr76gag and pr66gag) from [35s]methionine-labelled chicken embryo fibroblasts transformed by the schmidt-ruppin strain of ... | 1982 | 6292357 |
| structure-function relationship of rous sarcoma virus leader rna. | cells infected by rsv synthesize viral 35s rna as well as subgenomic 28s and 22s rnas coding for the env and src genes respectively. in addition, at least the 5' 101 nucleotides of the leader are also conserved and we have shown previously that this sequence contains a strong ribosome binding site (j.-l. darlix et al., j. virol. 29, 597). we now report the rna sequence of rous sarcoma virus (rsv) leader rna and propose a folding of this 5' untranslated region which brings the cap, the initiation ... | 1982 | 6292833 |
| effect of intron size on splicing efficiency in retroviral transcripts. | to study the effect of intron size on splicing efficiency we have varied the size of the avian leukosis virus (alv) env mrna intron in a cloned alv genome. this was accomplished by deletion of alv sequences or insertion of phage lambda dna. the effect of these modifications on splicing was analyzed by microinjection of the modified clones into rsv(-) chicken cells. viral env mrna when transcribed and properly spliced within these cells complemented the rsv(-) env deficiency leading to the produc ... | 1982 | 6292870 |
| cells transformed by rous sarcoma virus release transforming growth factors. | chicken embryo fibroblasts and hamster bhk cells transformed by rous sarcoma virus (rsv) release in their culture media growth factors which enhance markedly anchorage-independent colony formation in gelified medium, at the restrictive temperature (41 degrees 5 c), of chicken embryo fibroblasts (cef) infected by rsv mutants with a ts mutation of the src gene. this action is not observed with uninfected cef, and, therefore, appears to require some expression of the viral src gene in the target ce ... | 1982 | 6294124 |
| production of plasminogen activator by synchronized normal and rous sarcoma virus-transformed chicken fibroblasts in culture. | we studied intracellular activity of the plasminogen activator within the cell cycle of chemically synchronized normal and rsv-transformed chick fibroblasts in culture. consideration has also been given to the relationship between the plasminogen activator activity and cycles of dna synthesis or mitosis in cycling fibroblasts after viral infection. the plasminogen activator activity of the cell lysates was assayed on [125i]fibrin-coated petri dishes and was expressed as the radioactivity release ... | 1982 | 6295505 |
| enhancement of plasminogen activator activity by the culture medium of rous sarcoma virus-transformed cells. | we have tested the effect of the culture medium of chicken embryo fibroblasts (cef) transformed by rous sarcoma virus (rsv) on plasminogen activator (pa) activity of normal and rsv-infected cells. the results obtained showed that fibrin digestion by cultures of normal uninfected and rsv-infected cells directly attached to a fibrin substrate was increased when the cells were exposed to the supernatant of an 18 h-culture of cef transformed by rsv. addition of cycloheximide to the supernatant compl ... | 1982 | 6296283 |
| characterization of stable spontaneous metastatic variant lines of rsv-transformed mouse fibroblasts. | the correlation between metastatic potential and a series of biological properties was investigated in two mouse fibrosarcoma lines (sr-balb and b77-3t3), transformed by different strains of rous sarcoma virus (rsv). in the absence of selective pressure the metastatic potential was different in the two lines. the sr-balb sarcoma did produce both spontaneous metastases from s.c. site and i.v. lung colonization with a high incidence (respectively in 60% and 80% of treated animals). conversely, the ... | 1982 | 6298121 |
| sequence comparison in the crossover region of an oncogenic avian retrovirus recombinant and its nononcogenic parent: genetic regions that control growth rate and oncogenic potential. | ntre 7 is an avian retrovirus recombinant of the endogenous nononcogenic rous-associated virus-0 (rav-0) and the oncogenic, exogenous, transformation-defective (td) prague strain of rous sarcoma virus b (td-prrsv-b). oligonucleotide mapping had shown that the recombinant virus is indistinguishable from its rav-0 parent except for the 3'-end sequences, which were derived from td-prrsv-b. however, the virus exhibits properties which are typical of an exogenous virus: it grows to high titers in tis ... | 1982 | 6298596 |
| interaction between the rous sarcoma virus transforming protein and two cellular phosphoproteins: analysis of the turnover and distribution of this complex. | the transforming protein of rous sarcoma virus (rsv), pp60src, was previously shown to associate with two cellular proteins of mr 90,000 and 50,000 in rsv-transformed chicken cells. in this report, we demonstrate that this interaction is specific for a discrete population of pp60src molecules. newly synthesized pp60src was found to preferentially associate with pp90 and pp50 to form a short-lived complex. the half-life of this complex varied from 9 to 15 min in cells transformed by nondefective ... | 1983 | 6298609 |
| two cellular proteins that are precipitated by an antitumor-rsv rat serum. | here we report studies on non-viral proteins specific for transformation precipitated by immune sera. these sera were from rats injected by pr-rsv transformed rat xc cells and from rabbits immunized by subcutaneous injections of cytoplasmic membranes from rat cells transformed by fujinami avian sarcoma virus. immune complexes were analyzed in one- or two-dimensional gel electrophoresis and by autoradiography. only by using antisera obtained from rats bearing xc-cells induced tumors, two proteins ... | 1982 | 6298644 |
| nucleotide sequence of rous sarcoma virus. | we present the 9312 nucleotide sequence of the prague c (pr-c) strain of rous sarcoma virus (rsv). a comparison of known protein sequences with the nucleotide sequence allows assignment of the coding regions for the gag, pol, env and src genes. the gag gene is terminated by an amber stop codon and is contained within a different reading frame than is the pol gene. the pol and env genes overlap. the sequences surrounding the src gene in the pr-c and schmidt-ruppin (sr-a) strains of rsv have been ... | 1983 | 6299578 |
| structure and sequence of the cellular gene homologous to the rsv src gene and the mechanism for generating the transforming virus. | we determined the nucleotide sequences of all coding regions and a significant part of the flanking regions of the chicken c-src gene, which is a cellular homolog of the v-src gene of rous sarcoma virus. the c-src gene consists of 12 exons; the boundaries of the exons were determined by assuming that the amino acid sequence of its product, pp60c-src, is basically the same as that of pp60v-src. the deduced amino acid sequence of pp60c-src was very similar to that of pp60v-src, but the last 19 car ... | 1983 | 6299580 |
| inhibition of rous sarcoma virus-induced transformation by preinfection with rhabdoviruses. | in vivo preinfection of chicks with rabies virus (rv) or vesicular stomatitis virus (vsv) ts 1026 inhibits tumour formation after superinfection with rous sarcoma virus (rsv). the degree of inhibition depends on the titre of the infecting viruses and the interval between rhabdovirus and rsv infection. in vitro, cells preinfected with vsv ts 1026 under non-permissive conditions and superinfected with rsv, are not transformed as judged by cell morphology, serum requirement for growth or the capaci ... | 1983 | 6300284 |
| a neuronal clone derived from a rous sarcoma virus-transformed quail embryo neuroretina established culture. | neuroretina (nr) is an evagination of the central nervous system (cns) which is composed of photoreceptors, glial (müller) cells and horizontal, bipolar, amacrine and ganglion neuronal cells. we describe here the usefulness of rous sarcoma virus (rsv) in the establishment of a neuronal clone from quail embryo neuroretina. when primary cultures of chick and quail embryo neuroretina cells are transformed by rsv, neuronal markers such as ribbon synapses, choline acetyltransferase (cat) and glutamic ... | 1983 | 6300691 |
| the comparative effects of tumor-related agents on developmental marker expression in presumptive myoblasts and myotubes. | the effect of a tumor promoter, 12-o-tetradecanoylphorbol-13-acetate (tpa), on differentiation marker expression in skeletal myotubes and their immediate progenitors, presumptive myoblasts (pmbs), was investigated. the markers employed included the k-isozyme of pyruvate kinase (pk-k) and a newly characterized phosphoprotein (pp(65;4.5)), which are both normally concentrated in pmbs, and the m-isozyme of pyruvate kinase (pk-m) and phosphorylated derivatives of alpha- and beta-tropomyosin (pt), wh ... | 1983 | 6301863 |
| inhibition of precartilaginous chick somites by oncogenic virus. | infection of embryonic chicken notochord-somite explants with rous sarcoma virus inhibited the in vitro differentiation of somites into cartilage. visual inspection of the explants revealed that viral infection reduced the size of cartilage nodule formation. formation of the complex of sulfated proteoglycans with hyaluronic acid was inhibited by rsv infection, and sedimentation analysis of the sulfated proteoglycans showed that very little fast sedimenting proteoglycans were synthesized by rsv-i ... | 1983 | 6301911 |
| improved method for detection of cellular transcripts by in situ hybridization. detection of virus-specific rna in rous sarcoma virus-infected cells by in situ hybridization to cdna. | optimal conditions for the detection of complex rna sequences in individual cells by in situ hybridization have been determined by using in vitro cultured quail embryonic cells infected with rous sarcoma virus and a single-stranded 3h-cdna probe of high specific activity complementary to the rsv genome. it is shown that fixation of target tissue can be suitably achieved by using glutaraldehyde at low concentration, and subjecting cytological preparations to heat post-fixation treatment. conditio ... | 1983 | 6302035 |
| association of pp36, a phosphorylated form of the presumed target protein for the src protein of rous sarcoma virus, with the membrane of chicken cells transformed by rous sarcoma virus. | a cellular protein with a molecular mass of approximately 36 kilodaltons is the presumed target protein of the src protein [the transforming protein encoded by rous sarcoma virus (rsv)]. the cellular location of the phosphorylated 36-kilo-dalton protein (pp36) in chicken embryo fibroblasts transformed by the schmidt-ruppin strain of rsv has been investigated. in these studies, two-dimensional electrophoresis was used for detection of the phosphoproteins in total cell extracts and also in fractio ... | 1983 | 6302677 |
| transduction of a cellular oncogene: the genesis of rous sarcoma virus. | the oncogene of rous sarcoma virus (v-src) arose by transduction of a cellular gene (c-src). in an effort to explore the mechanism of transduction, we have identified the splice acceptor site used in the genesis of mrna for v-src, shown that an equivalent site is used in the splicing of mrna for c-src, and determined the nucleotide sequence from the boundaries of homology between v-src and c-src. our data indicate that (i) only a portion of c-src is represented within v-src, (ii) the leftward re ... | 1983 | 6302692 |
| the effect of microtubule disruption on the distribution of the cytoskeletal proteins, vinculin, alpha-actinin, and actin in normal and rsv-transformed fibroblasts. | by double indirect immunofluorescence and interference electron microscopy, we have observed the effect of microtubule disruption by antimitotic drugs and coldness treatment on the distribution of adhesion sites and of the three cytoskeletal proteins, vinculin, alpha-actinin, and actin in normal rat cells and in rat cells transformed by rous sarcoma virus. this study shows that the state of organization of the microtubule--intermediate filament complex modulates the location and the arrangement ... | 1983 | 6303790 |
| transformation-sensitive isoactin in passaged chick embryo fibroblasts transformed by rous sarcoma virus. | transformation by rous sarcoma virus (rsv) has been reported to block the expression of differentiated cell products in chicken cells. the expression of these proteins may or may not be suppressed when temperature-sensitive mutants are shifted from the nonpermissive to the permissive temperature. a general characteristic of cellular transformation is the disruption of the microfilament system. in passaged chick embryo fibroblast cultures (cef), this system is principally composed of isomeric for ... | 1983 | 6304115 |
| complete sequence of the rous sarcoma virus env gene: identification of structural and functional regions of its product. | the amino-terminal amino acid sequences of gp85 and gp37, the envelope glycoproteins of rous sarcoma virus (rsv), were determined. alignment of these sequences with the amino acid sequence predicted from the complete nucleotide sequence of the prague strain of rsv, subgroup c (pr-c), has allowed us to delineate the env gene-coding region of this virus. the coding sequences for gp85 and gp37 have been placed in an open reading frame that extends from nucleotide 5045 to nucleotide 6862 and predict ... | 1983 | 6304351 |
| transformation-defective rous sarcoma virus mutants with altered p19 of the gag gene and their inhibitory effect on host cell growth. | mutants (ph2010, ph2011, ph2012) of rous sarcoma virus which have a growth-inhibitory effect on chicken embryo fibroblasts were isolated from a temperature-sensitive mutant of the schmidt-ruppin strain of rous sarcoma virus (tsny68). the growth rate of fibroblasts infected with these viruses was about 50 to 60% of that of uninfected fibroblasts. a morphological difference between mutant-infected and uninfected fibroblasts was observed at logarithmic phase but not at stationary phase. neither the ... | 1983 | 6304352 |
| correlation between tumor-specific surface antigens and src gene expression in rous sarcoma virus-induced rat tumors. | immunization with rous sarcoma virus (rsv)-induced mouse tumors or with sr-3y1 or ny8-3y1 rat fibroblasts transformed by a wild type rsv or an env gene deletion mutant of rsv induced complete transplantation resistance against an rsv-induced mouse tumor (csa1m) in syngeneic hosts. on the other hand, 10 of 19 mice immunized with ts68-3y1 rat fibroblasts transformed by an src gene temperature-sensitive mutant of rsv (permissive temperature: 33-35 degrees c) could not reject the csa1m. sr-3y1, ny8- ... | 1983 | 6305667 |
| characterization of t lymphocytes mediating in vivo protection against rsv-induced murine sarcomas. | tumors induced by rous sarcoma virus (rsv) in different mouse strains share a common tumor-associated transplantation antigen, whose expression is controlled both by the viral transforming src gene and by cellular gene(s) (prat et al., 1981). the mechanism(s) responsible for the in vivo protective immune response against two rsv-induced sarcomas has now been investigated. in the "winn assay" the growth of both tumors was specifically prevented or significantly reduced by the simultaneous adminis ... | 1983 | 6305851 |
| analysis of the pathogenicity of transformation defective partial deletion mutants of avian sarcoma virus: characterization of recovered viruses which encode novel src specific proteins. | several transformation defective (td) mutants of the prague strain of rous sarcoma virus, which had been previously shown to have deletions of varying sizes and positions within the src gene, were tested for their ability to induce disease in chickens. several of the mutants induced sarcomas after long latency, in particular two mutants which had deletions spanning the presumed active site (i.e., the phosphotyrosine residue) of the rsv transforming protein, pp60src. viruses recovered from these ... | 1983 | 6306917 |
| location and function of retroviral and sv40 sequences that enhance biochemical transformation after microinjection of dna. | biochemical transformation of thymidine-kinase-deficient (tk-) mouse l cells is enhanced 20 to 40 fold when microinjected plasmid dna contains regions of the genomes of rous sarcoma virus or simian virus 40 in addition to the complete herpes simplex virus tk gene, irrespective of the orientation and location of the enhancer. the enhancing sequence of rsv dna has been localized to 143 bp that include 88 bp at the 5' end of the long terminal repeat; the enhancing segment of sv40 dna lies 42-276 bp ... | 1983 | 6307525 |
| localization of provirus dna of rous sarcoma virus in the dna of infected, transformed and tumour cells of chickens. | the integration of the rsv provirus genome into chicken cell dna was studied by restriction analysis at various times after infection with rsv. one to two copies of provirus dna per cell genome are integrated and integration occurs at different sites of dna without apparent specificity, independently of the stage of infection and transformation of cells. the exogenous virus dna is integrated into cell genome independently of the endogenous proviruses. the number of integrated proviruses does not ... | 1983 | 6307764 |
| genetic linkage of subgroup c rous sarcoma virus-induced tumour expression in chickens to the ir-gat locus of the b complex. | two b complex genotypes, b1b1 and b19b19, of outbred line s1, were tested for low and high immune response to gat, from which four recombinants were recovered: b1b1 gat-hi and -lo, and b19b19 gat-hi and -lo. also included in the study were birds of b2b2 genotype with an intermediate level of immune response to gat. a total of 225 birds of these groups were challenged with the bryan strain of rous sarcoma virus subgroup c, rsv (rav-7), by inoculation into the wing web at five weeks of age. the b1 ... | 1983 | 6308101 |
| amplification of the provirus region in rous sarcoma virus-transformed chinese hamster cells and segregation of the amplified copies in somatic cell hybrids. | four independent clones of rsv-transformed chinese hamster fibroblasts were isolated. southern blots and dot hybridization studies showed that in three out of four clones there were four to eight times as many integrated proviruses as in the fourth clone which contained at least one complete provirus. restriction mapping studies showed that although the integration site varied from clone to clone, all the proviral copies in the same clone shared the same flanking cellular sequences. in one clone ... | 1983 | 6308888 |
| characterization of exogenous proviral sequences in hamster tumor cell lines transformed by rous sarcoma virus rescued from xc cells. | alterations in viral structural genes have been studied in five cell lines derived from syrian hamster tumors which had been induced by the virus rescued from xc cells by transfection. two cell lines, h-18 and h-20, have all the viral structural genes expressed, but a new ecori recognition site appeared in the region of the pol gene sequence. provirus present in h-12 lacks the 3' part of the gag gene sequences as well as the pol gene, therefore, it gives rise to an anomalous 1.8 md ecori fragmen ... | 1983 | 6308892 |
| a new avian erythroblastosis virus, aev-h, carries erbb gene responsible for the induction of both erythroblastosis and sarcomas. | the genome structure of a newly isolated avian erythroblastosis virus, aev-h, was analyzed. using dna probes specific for the ltr sequence of sr-rsv-a, and for the erba gene and the erbb gene of the es4 strain of aev, we have shown that the genome of aev-h is 35s in size and carries the erbb gene but not the erba gene. comparison of the restriction sites of molecularly cloned aev-h dna with that of cloned dna of the associated virus revealed that the env gene of the associated virus was replaced ... | 1983 | 6309409 |
| activation of oxidative and arachidonic acid metabolism in neutrophils by respiratory syncytial virus antibody complexes: possible role in disease. | the effect of respiratory syncytial virus (rsv) antibody complexes on the metabolism of human neutrophils was determined by examining the generation of luminol-dependent chemiluminescence, superoxide, and thromboxane b2. incubation of neutrophils with rsv antibody complexes resulted in a significant increase in the production of chemiluminescence. the increase in chemiluminescence appeared to be due to (1) active phagocytosis of rsv antibody complexes as evidenced by 70% inhibition with cytochal ... | 1983 | 6309990 |
| high spontaneous mutation rate of rous sarcoma virus demonstrated by direct sequencing of the rna genome. | direct and extensive sequencing of rsv rna genome is reported. more than 10,000 nt of the t1 rnase resistant rsv rna fragments (1) have been sequenced and shown to cover 3900 nt of rsv genome. the frequent sequence variations found indicate that rsv supports a very high incidence of spontaneous mutations in the course of replication, one very probable cause of the genetic diversity among the avian retroviruses. sequences of the structured rsv rnas allowed us also to precisely characterize the st ... | 1983 | 6310522 |
| selective ligation of dna molecules following microinjection. | avian retroviral dna is rapidly ligated and transcribed following microinjection into chick cells. to analyze the fidelity of intranuclear ligations, dna molecules with a variety of protruding ends or flush ends were co-injected into env-deficient rous sarcoma virus-infected (rsv(-] cells. two fragments were chosen which could complement the rsv(-) env deficiency upon ligation. this sensitive biological assay indicated that intracellular ligation between molecules with complementary protruding e ... | 1983 | 6311814 |
| isolation of monoclonal antibodies that recognize the transforming proteins of avian sarcoma viruses. | thirteen clones of hybrid cells which synthesize antibodies directed against the rous sarcoma virus (rsv) transforming protein, pp60src, were isolated. mouse myeloma cells were fused with spleen cells from mice that had been immunized with purified pp60src from bacterial recombinants which direct the synthesis of the rsv src gene. the hybridomas which survived the selection medium were screened by immunoprecipitation of pp60src from 32p-labeled lysates of rsv-transformed cells. monoclonal antibo ... | 1983 | 6312092 |
| susceptibility of rous sarcoma virus-specific sequences integrated into sr-c3h/he mouse ascites sarcoma cell chromatin to dnase i and dnase ii. | the susceptibility of rous sarcoma virus (rsv) genomes integrated in mouse ascites sarcoma cells (sr-c3h/he cells) to dnase i and dnase ii was investigated. approximately half of the viral sequences were sensitive to dnase i and dnase ii when 17% and 7.4% of the chromatin dna was rendered acid soluble, respectively. the results suggest that newly acquired exogenous proviral sequences are integrated into both transcriptionally active and inactive regions of chromatin in cells lacking related endo ... | 1983 | 6312767 |
| regulation and drug insensitivity of f-actin association with adhesion areas of transformed cells. | f-actin aggregates have been found near the substrate attachments in a variety of transformed cells (carley et al., 1981). interference reflection microscopy shows that these aggregates are present in central close adhesion areas in rous sarcoma virus (rsv)-transformed rat kidney cells. if these transformed cells are incubated with n6, o2-dibutyryl 3':5'-cyclic monophosphoric acid (db-camp), adenosine 5'-monophosphoric acid (5'-amp) or adenosine, the f-actin aggregates and their associated close ... | 1983 | 6313706 |
| antibodies against a synthetic peptide of the avian retrovirus pp32 protein and the beta dna polymerase subunit. | antibodies directed against a synthetic peptide (14 amino acids in length), whose amino acid sequence was predicted from the nucleotide sequence of the polymerase gene of rous sarcoma virus (rsv), specifically immunoprecipitated the rsv beta polymerase subunit and the pp32 protein but not the alpha polymerase subunit. the first amino acid of the synthetic peptide is located approximately 30,800 da from the predicted carboxyl terminus of the polymerase gene. these studies confirm the correct read ... | 1983 | 6314648 |
| [transformation of diploid human fibroblasts and viral production after infection by avian retroviruses]. | among the cultures established from skin biopsies of 128 donors, two were transformed by rsv and produced virus. one out of 6 cellular lines developed from six human sarcomas was likewise transformed and also produced virus. | 1983 | 6315192 |
| evidence that avian tumour virus-immune chicken sera recognize only viral structural antigens on the surface of avian tumour virus-infected cells. | the specificity of the humoral response of chickens to avian tumour viruses (atv) was investigated by reacting atv-immune sera with triton x-100 extracts of uninfected, infected and transformed chicken embryo fibroblasts. analysis of these immune reactions by polyacrylamide gel electrophoresis revealed that avian leukosis virus-challenged and rous sarcoma virus-challenged chickens recognized only two major cell surface antigens of 100000 and 29000 mol. wt. which were present on transformed and n ... | 1983 | 6315863 |
| [contribution of direct immunofluorescence diagnosis to the epidemiology of acute viral respiratory infections in young children]. | rapid diagnosis by immunofluorescence (if) has enabled us to study the epidemiology of acute viral respiratory diseases in infants admitted to the chru at caen between january 1980 and december 1982. 809 nasal aspiration samples were examined. respiratory syncytial virus (rsv) was recovered in 36% of cases. these were observed during the four winter outbreaks which occurred during the study period and were extensive in 1980-1981 and 1982-1983. a virus was demonstrated in 13.5% of the 515 rsv neg ... | 1983 | 6316549 |
| [a thermosensitive characteristic of the schmidt rupin strain of rous sarcoma virus affecting the longevity of infected lines]. | quail embryo skin fibroblasts infected with wild type rous sarcoma virus sr-rsv grow, at 36 or 41 degrees c, twice as fast (30 hours. mean division time) as the uninfected controls or the cells infected with rav-1 virus. at 36 degrees c the sr-rsv infected cells stop growing after the same delay as the controls, thus having undergone twice as many doublings, (38 to 40 instead 18 to 20). however, at 41 degrees c, sr-rsv infected cells stop 5 to 6 divisions earlier. this cannot be reversed by shif ... | 1983 | 6318934 |
| study of pp60v-src protein kinase activity in synchronized chicken embryo fibroblasts infected with rous sarcoma virus. | chicken embryo fibroblast (cef) cultures, synchronized by the addition of serum to stationary cells, were exposed to schmidt-ruppin strain of rous sarcoma virus (sr-rsv) and the appearance of pp60v-src protein kinase activity was examined through the cell cycle. in cells infected either at the beginning or at the end of g1, the onset of pp60v-src protein kinase activity was coincidental, closely following mitosis, with a delay between the infection of cells with sr-rsv and the appearance of prot ... | 1984 | 6319162 |
| unphosphorylated gelsolin is localized in regions of cell-substratum contact or attachment in rous sarcoma virus-transformed rat cells. | regions associated with cell-substratum contact or attachment in rous sarcoma virus (rsv)-transformed rat fibroblasts (rr1022 cells) were identified by reflection-interference microscopy. electron microscopy of such regions revealed the presence of discrete membrane-associated structures composed of a paracrystalline lattice of hexagons and pentagons to which actin filaments appear to be attached. staining of actin by biotin-labeled heavy meromyosin showed that transformed cells, unlike normal f ... | 1984 | 6319434 |
| dna sequence of the bryan high-titer strain of rous sarcoma virus: extent of env deletion and possible genealogical relationship with other viral strains. | the genetic structure of the bryan high-titer strain of rous sarcoma virus (bh-rsv) was analyzed by using a molecular clone obtained from proviral dna. dna sequencing of the pol-src junction of bh-rsv revealed that the env sequence was almost entirely absent; only six base pairs following the pol termination codon remained. beginning at nucleotide 7 (relative to the end of pol), a 91-base pair sequence identical to the 91 base pairs immediately upstream from src in other strains of rsv was found ... | 1984 | 6319754 |
| independent expression of common and private tumor-specific cell surface antigens in somatic cell hybrids between rous sarcoma virus-transformed and normal cells. | somatic cell hybrids were prepared by fusion of a rous sarcoma virus (rsv)-induced mouse tumor (csa1m cl-11) with a chinese hamster embryo lung fibroblast line (wg3h x agr x ouar). some hybrid clones showed rapid anchorage-independent growth and intracellular production of rsv-pp60src. other hybrid clones showed slow anchorage-dependent growth and no production of such a protein. the former expressed both a common tumor-specific cell surface antigen(s) (tssa) shared with other rsv-induced tumors ... | 1984 | 6319792 |
| globin expression in rous sarcoma virus-transformed quail myoblasts. | viral transformation affects certain developmental processes by blocking the differentiation of cells such as primitive muscle cells (myoblasts) or primitive red blood cells (erythroblasts). embryonic quail myoblasts, transformed with a temperature-sensitive (ts) mutant of rous sarcoma virus (rsv) are blocked in differentiation at the viral permissive temperature of 35 degrees c, but fuse to form myotubes at the nonpermissive temperature of 41 degrees c. we have shown that viral transformation o ... | 1983 | 6320215 |
| [viruses and asthma]. | more than one-third of infants with respiratory syncytial virus (rsv) bronchiolitis subsequently experience recurrent episodes of wheezing. in asthmatic children, viral infections frequently trigger asthmatic attacks. indeed, viruses induce immunological and respiratory functional disorders. as compared with non-wheezing rsv infected infants, wheezing infants with bronchiolitis or asthma due to rsv have: a) increased t-lymphocyte responsiveness to rsv antigen; b) more persistent ige bound to nas ... | 1983 | 6320377 |
| processing of gpr92env, the precursor to the glycoproteins of rous sarcoma virus: use of inhibitors of oligosaccharide trimming and glycoprotein transport. | a number of aspects of the processing of gpr92env, the precursor to the viral glycoproteins gp85 and gp35 of rous sarcoma virus (rsv), have been studied. first, the kinetics of gpr92env processing have been examined, revealing that the precursor is overproduced in the infected cell and only a small percentage (less than 5%) is converted into mature glycoprotein in virus particles. second, the effects of inhibitors of intracellular transport (monensin) and oligosaccharide trimming (n-methyl-1-deo ... | 1984 | 6320537 |
| loss of proviral sequences in rsv-transformed mouse tumour cells accompanied by the formation of double-minute chromatin bodies. | the rva2 cell line, derived originally from a tumour induced by the schmidt-ruppin strain of rsv and passaged repeatedly in vivo and in vitro, was studied. this cell line was originally virogenic and the virus was rescuable with high efficiency from it. when rechecked after prolonged passage history, the efficiency of virus rescue was found to drop to very low levels and from one monocellular clone derived from such cell population no virus was rescued at all. after further 14 in vivo passages o ... | 1983 | 6321249 |
| butyrate reversibly arrests the proliferation of normal and rous sarcoma virus-infected chicken heart mesenchymal cells. | sodium butyrate at 5 x 10(-3) m reversibly arrests the proliferation of both normal and rsv-infected chicken heart mesenchymal cells. this finding suggests that butyrate acts by causing non-specific inhibition of cell proliferation, rather then by specifically suppressing the neoplastic phenotype or by inducing recovery of cells from the neoplastic state. | 1984 | 6321872 |
| monoclonal antibodies specific for the avian sarcoma virus transforming protein pp60src. | monoclonal antibodies to avian sarcoma/leukosis virus-coded transforming, structural, and polymerase proteins have been developed. in this first communication, a monoclonal antibody to pp60src will be characterized. the antibody can bind to pp60src in radioimmunoassays, precipitates this antigen in protein kinase tests, and demonstrates in immunofluorescence investigations that pp60src has different intracellular localizations depending on whether rsv-transformed avian or mammalian cells are stu ... | 1984 | 6322430 |
| treatment of respiratory viral infection in an immunodeficient infant with ribavirin aerosol. | an infant with severe combined immunodeficiency syndrome (scids) secondary to adenosine deaminase deficiency had pneumonitis and combined infection with respiratory syncytial virus (rsv) and parainfluenza virus type 3 (piv3). four separate courses of ribavirin were delivered by small-particle aerosol. the piv3 disappeared during the first course, and rsv disappeared after the fourth course on the 58th hospital day. neither virus returned during profound immunosuppression for bone marrow transpla ... | 1984 | 6322573 |
| cytoskeleton and adhesion patterns of cultured chick embryo chondrocytes during cell spreading and rous sarcoma virus transformation. | the cytoskeleton and the adhesion complex of chick embryo chondrocytes maintained in vitro have been studied by fluorescence and interference reflection microscopy during the process of cell spreading. the pattern of actin-containing microfilaments and the distribution of vinculin speckles on adhesion plaques have been found to change as a function of the culture time. newly plated chondrocytes adhere to the substratum mostly around a peripheral ring-like region and show a complex tridimensional ... | 1984 | 6323198 |
| density-dependent inhibition of growth: inhibitory diffusible factors from 3t3- and rous sarcoma virus (rsv)-transformed 3t3 cells. | we recently fractionated, from the culture medium of 3t3 cells, a thermolabile inhibitory diffusible factor (idfn) with a molecular weight of about 40,000 daltons, which decreased nucleic acids synthesis of stimulated target 3t3 cells. in the present publication the inhibitory activities of idfn (produced by 3t3 cells) and idft (produced by rsv-transformed 3t3 [3t3 sra/h] cells) on 3t3 and 3t3 sra/h cells have been compared. the inhibitory activity of idfn decreased (by a mean of 57%) when it wa ... | 1984 | 6323487 |
| it is rous sarcoma virus protein p12 and not p19 that binds tightly to rous sarcoma virus rna. | the interactions between rous sarcoma virus (rsv) rna and the viral proteins in the virus have been analysed by sen & todaro (1977) using ultraviolet light irradiation; they showed that the major protein ultraviolet light cross-linked to the viral rna was p19 as identified by polyacrylamide gel electrophoresis. we report here that it is not viral protein p19 but p12 that binds tightly to rsv rna upon ultraviolet light irradiation of the virus. therefore, the binding sites of the viral protein al ... | 1984 | 6323722 |
| hematopoietic cell transformation by a murine recombinant retrovirus containing the src gene of rous sarcoma virus. | a recombinant murine retrovirus (mrsv) containing the src gene of avian rous sarcoma virus (rsv) was shown to induce hematopoietic colonies in infected mouse bone marrow. mrsv-induced colony formation followed single-hit kinetics and required mercaptoethanol in the agar medium. cells from the colonies induced by mrsv could be established as continuous cell lines that demonstrated unrestricted self-renewal in vitro and tumorigenicity in vivo. the transformants, all of which expressed high levels ... | 1984 | 6326123 |
| an in vitro screening method for antitumor and/or antitumorigenic substances involving the transformation of chick embryo fibroblasts infected with rous sarcoma virus. | an efficient in vitro screening method for antitumor and/or antitumorigenic substances was established. the method is based on determining inhibitory effect of a compound on an rsv-induced tumorigenic process and the growth of the established tumor cells in a single assay system in the presence of normal cells. these effects were determined by inhibition of focus formation in a culture of chick embryo fibroblasts, while the nonspecific cytotoxic effect was determined by inhibition of the protein ... | 1984 | 6327589 |
| dnase i sensitivity of the alpha 2(i) collagen gene: correlation with its expression but not with its methylation pattern. | the chromatin structure of the chick alpha 2(i) collagen gene was probed with dnase i. because our previous work strongly suggested that the 5' end of this gene is not methylated whereas the rest of the gene is methylated whether or not the gene is expressed, we compared the relative dnase i sensitivity of the methylated and unmethylated segments. both regions demonstrate similar relative dnase i sensitivities within a given tissue. in chromatin of chick embryo fibroblasts, we find a dnase i hyp ... | 1984 | 6328424 |
| cytoskeletal changes induced by two avian sarcoma viruses: ur2 and rous sarcoma virus. | ur2-transformed cells were examined by immunofluorescence and compared to control cells and cells transformed by rous sarcoma virus (rsv). actin and tubulin which are normally depolymerized in rsv-transformed cells appeared to be unaffected by ur2 transformation. cell surface fibronectin which is normally lost from rsv-infected cells, appears more abundantly on ur2-transformed cells than on normal cells. vinculin was shown to be in adhesion plaques in ur2-transformed cells as well as in control ... | 1984 | 6330996 |
| cell-mediated cytotoxic responses in lungs of cotton rats infected with respiratory syncytial virus. | pneumonia induced in cotton rats (sigmodon hispidus) after inoculation of respiratory syncytial virus (rsv) was accompanied by the appearance of leukocytes in infected lungs. the number of these leukocytes increased until day 5 after inoculation when sixfold more leukocytes were recovered from infected lungs using transpleural lavage than were recovered from lungs of uninfected control animals. although macrophages and lymphocytes constituted approximately 65 and 25%, respectively, of the cells ... | 1983 | 6340570 |
| ribavirin treatment of experimental respiratory syncytial viral infection. a controlled double-blind study in young adults. | the effect of ribavirin aerosol on experimental respiratory syncytial virus (rsv) infection was evaluated in a double-blind controlled study of 16 young adult volunteers. two days after intranasal inoculation with rsv, half of the subjects were treated with a small-particle aerosol of ribavirin and half with placebo for a total of 12 hours each day for three days. seven of eight placebo-treated and six of eight ribavirin-treated subjects became infected. viral shedding was diminished in the riba ... | 1983 | 6341640 |
| rapid detection of respiratory syncytial virus with a monoclonal antibody. | we developed an indirect fluorescent-antibody test employing a mouse monoclonal antibody directed against the nucleoprotein of rsv for rapid detection of respiratory syncytial virus (rsv). this test demonstrated distinctive fluorescent inclusions in hep-2 cells infected with 24 rsv isolates collected during 6 previous years but not in cells infected with 13 other respiratory viruses. examination of nasal cells of 100 infants with acute respiratory illness showed that the indirect fluorescent-ant ... | 1983 | 6348077 |
| mechanisms of immunity to respiratory syncytial virus in cotton rats. | active immunity and maternally transmitted passive immunity to respiratory syncytial virus (rsv) were studied in cotton rats. animals infected with respiratory syncytial virus developed complete resistance to pulmonary reinfection, which lasted at least 18 months. nasal resistance was of shorter duration and began to diminish in 8 months. pulmonary resistance was transferred by parabiosis, but nasal resistance was not. adoptive transfer studies with fractionated convalescent blood showed that se ... | 1983 | 6352505 |
| experimental respiratory syncytial virus pneumonia in young calves: microbiologic and immunofluorescent findings. | young calves were inoculated with respiratory syncytial virus (rsv) intranasally or by a combined intranasal and intratracheal route and were killed between postinoculation (initial) days (pid) 1 and 14. viral antigens were detected by immunofluorescence in nasopharyngeal cells from calves killed between pid 2 and 10. evidence of infection of the trachea and lungs with rsv was obtained by immunofluorescence and virus isolation in calves inoculated by the combined route, but not in calves inocula ... | 1983 | 6354017 |
| correlation of cytotoxic activity in lungs to recovery of normal and gamma-irradiated cotton rats from respiratory syncytial virus infection. | cotton rats (sigmodon hispidus) that were exposed to 300, 600, or 900 rads of gamma irradiation and inoculated intranasally 2 days later with respiratory syncytial virus (rsv) exhibited prolonged virus shedding and delayed humoral and cytotoxic immune responses compared with comparably inoculated nonirradiated control rats. in nonirradiated animals and in animals exposed to 300 and 600 rads, levels of virus declined and then disappeared from the lungs during the period in which cytotoxic activit ... | 1983 | 6354026 |
| respiratory syncytial virus detection by immunofluorescence in nasal secretions with monoclonal antibodies against selected surface and internal proteins. | specimens containing respiratory tract epithelial cells from infants and children with acute respiratory disease were evaluated by using an indirect immunofluorescence technique with two specific respiratory syncytial virus monoclonal antibodies. one (rs/hn 13-1) was directed against a cell surface viral antigen, and the other (rs/hn 25-2) was directed against viral antigen present in large cytoplasmic inclusions. the same results on presence or absence of respiratory syncytial virus were obtain ... | 1983 | 6361054 |
| infection of gnotobiotic calves with a bovine and human isolate of respiratory syncytial virus. modification of the response by dexamethasone. | a bovine and a human strain of rsv both adapted to bovine cell culture, have been inoculated separately into 13 and 7 gnotobiotic calves respectively by 3 different methods. both strains infected calves and showed similar growth patterns. virus was recovered from the nasopharynx between one and 11 days with peak titres between 3 and 8 days following inoculation. with the exception of 4 calves treated with dexamethasone no clinical signs and only minimal macroscopic lesions of the lung were induc ... | 1984 | 6365036 |
| experimental pneumonia in gnotobiotic calves produced by respiratory syncytial virus. | a bovine isolate of respiratory syncytial virus (rsv), when inoculated intranasally into eight gnotobiotic calves produced significant macroscopic lesions of the lung (2-25% consolidation) but failed to produce any clinical signs of disease. the microscopic lesions comprised proliferative and exudative bronchiolitis with accompanying alveolar collapse and infiltration by mononuclear cells of the peribronchiolar tissue and alveolar walls. virus was recovered from the nasopharynx between days 2 an ... | 1984 | 6365144 |
| evidence for both respiratory syncytial virus and measles virus antigens in the osteoclasts of patients with paget's disease of bone. | recent ultrastructural and immunohistochemical evidence supports the hypothesis that paget's disease of bone is a slow viral infection of the paramyxoviridae family. conflicting evidence for the presence of respiratory syncytial virus (rsv), a pneumovirus, or measles, a morbillivirus, has been reported. by the indirect fluorescent antibody assay, four rsv antisera were compared with four measles antisera on serial sections of pagetic bone or replicate coverslips of cells from pagetic bone grown ... | 1984 | 6365389 |
| viral diagnoses using the rapid immunofluorescence technique and epidemiological implications of acute respiratory infections among children in different european countries. | from november 1978 to october 1981, a total of 7716 specimens of nasopharyngeal secretions were examined by the rapid immunofluorescence technique to determine the frequency of infections caused by the respiratory syncytial virus (rsv), influenza virus a, and parainfluenza viruses 1 and 3. the tests were carried out in six different virus laboratories located in newcastle upon tyne (england), copenhagen, oslo, stockholm, turku (finland), and vienna; laboratories in lisbon and paris participated ... | 1984 | 6375886 |
| isolation of pathogenic bacteria from the nasopharynx of children with respiratory syncytial virus infection. predictive value of chest roentgen examination and laboratory tests. | potentially pathogenic bacteria were isolated from the nasopharynx in 33/66 hospitalized infants and children with verified respiratory syncytial virus (rsv) infection. the value of chest roentgenograms and blood counts for the prediction of concomitant bacterial infection was evaluated. abnormal chest roentgenograms were found in 89% whether pathogenic bacteria were present or not. the most common finding was general hyperinflation of the lungs, with or without infiltrates. this occurred more f ... | 1984 | 6377479 |
| respiratory virus infection in hospitalized children in austria 1979-1982. diagnosis by immunofluorescence. | nasal secretions from 349 austrian children under six years of age who were hospitalized for respiratory illnesses were screened for the presence of respiratory syncytial virus (rsv), parainfluenza virus 1 and 3, adenovirus and influenza a virus over a period of four years by the immunofluorescence technique. 35% of the specimens were found to be positive for one of the five viruses investigated. rsv was detected in 31% of the nasal secretions and was thus the most frequently encountered causati ... | 1984 | 6381315 |
| pathogenesis of experimental bovine respiratory syncytial virus infection in sheep. | conventionally reared lambs, seronegative to bovine respiratory syncytial virus (rsv), were inoculated with bovine rsv by an aerosol route. a mild clinical response, characterized by transient fever at postinoculation day (pid) 4, occurred and was accompanied by serous oculonasal secretions in less than 50% of the infected lambs. a decrease in total wbc was observed on pid 6 and 11, with a reduction in the total numbers of lymphocytes. bovine rsv was recovered from nasal secretions of inoculated ... | 1984 | 6383151 |
| interaction of bovine respiratory syncytial virus and pasteurella haemolytica in the ovine lung. | the potential synergistic effect of bovine respiratory syncytial virus (rsv) and pasteurella haemolytica in the production of pneumonia after aerosol/intranasal infection of conventionally reared lambs was evaluated. a mild clinical response was observed in lambs given virus and/or bacteria. gross pulmonary lesions were seen in 3 of 6 lambs given rsv and then p haemolytica 3 or 6 days later, respectively (groups d and e), and in 1 lamb of 5 given virus and bacteria simultaneously (group g). gros ... | 1984 | 6383152 |
| immune response to respiratory syncytial virus: prevention of syncytia formation by human serum during in vitro infection. | human serum specimens containing respiratory syncytial virus (rsv)-specific neutralizing antibody were found to prevent the formation of syncytia when applied to hep-2 tissue culture monolayers which had been infected with rsv 12 h previously. this was evidenced by the demonstration of rsv-infected cells without any syncytia formation in the monolayers treated with rsv antibody-positive serum. on the other hand, widespread syncytia formation was observed with antibody-negative control serum. the ... | 1984 | 6387611 |
| three loci related to the src oncogene and tyrosine-specific protein kinase activity in drosophila. | rous sarcoma virus (rsv) is an acutely oncogenic avian retrovirus which induces sarcomas in animals and transforms fibroblasts in cell culture. genetic analysis indicates that the viral src gene (v-src) mediates neoplastic transformation. the product of v-src is a 60,000 molecular weight (mw) phosphoprotein (pp60v-src) possessing the enzymatic activity of a tyrosine-specific protein kinase. the viral src gene is derived from a cellular gene (c-src) which also encodes a 60,000 mw phosphoprotein ( ... | 1983 | 6405280 |