| efficacy of some disinfectants against infectious bursal disease virus and avian reovirus. | | 1982 | 6293154 |
| development of an attenuated apathogenic reovirus vaccine against viral arthritis/tenosynovitis. | a fully attenuated apathogenic reovirus vaccine was developed by 235 serial passages of s1133 strain avian reovirus in embryonating chicken eggs and 100 additional passages in chicken embryo fibroblast (cef) cultures, 65 of which were cultured at 32 c. chickens with and without maternal antibodies to avian reovirus were vaccinated subcutaneously at 1 day of age and challenged via footpad at 14 days of age. it appeared that the 40th, 66th, and 100th cef passage levels were apathogenic at doses ra ... | 1983 | 6314976 |
| modification of three avian viruses passaged in chinese hamster lung cells (don) in pathogenicity to chicken embryo. | the beaudette 42 strain of avian infectious bronchitis virus, sato strain of newcastle disease virus, and uchida strain of avian reovirus were passaged in chinese hamster lung cells (don), and some properties were examined. the don-passaged strains showed a difference in replication in don and chicken embryo kidney cells in one-step growth curve examinations and a partial modification in pathogenicity to chicken embryos; nevertheless, neutralization tests revealed no serological alteration. | 1984 | 6331368 |
| isolation of avian reovirus as a possible etiologic agent of osteoporosis ("brittle bone disease"; "femoral head necrosis") in broiler chickens. | avian reovirus was isolated from intestines of 3-to-7-day-old broiler chickens with enteritis from broiler houses where osteoporosis was a problem. the virus was purified in a cesium chloride gradient (buoyant density 1.37 gm/ml) and identified as a reovirus by electron microscopy. specific-pathogen-free (spf) chickens and commercial broiler chickens with anti-reovirus maternal antibodies inoculated at 1 day of age with the reovirus isolate developed lesions of femoral head fractures and/or oste ... | 1981 | 6461325 |
| avian reovirus antibody assay by indirect immunofluorescence using plastic microculture plates. | an indirect fluorescent antibody test was developed to detect serum antibody to avian reovirus strain wvu2937. this test employed small multiple well plastic plates (8 x 5.5 cm) which readily fitted into the standard mechanical stage mechanism of an incident light fluorescence microscope. the small wells of the plates required minimal (10 mul) volumes of reagents. in tests on 18 sera in which the indirect fluorescent antibody, agar gel precipitin and plaque reduction methods were compared sera w ... | 1982 | 6462191 |
| effects of feed additives and feed contaminants on the susceptibility of chickens to viruses. | several feed additives and contaminants are recognized which may alter avian immune responsiveness or disease resistance. exposure of poultry to such chemical substances may in some instances explain the failure of vaccines to confer expected levels of disease resistance and may explain certain flock health problems associated with infectious agents generally presumed to be commensals. limited studies with bht and ethoxyquin did not associate decreased resistance to ndv infection with dietary in ... | 1984 | 6483886 |
| detection of genomic differences between the avian reovirus isolate s1133 and its high-passage derivative p100. | previous studies have shown that the s1133 and p100 strains of avian reovirus are identical by electropherotype analysis of their genomic rna despite demonstrating differences in their protein composition. by using the more sensitive technique of liquid nucleic acid hybridization for comparing the genomes of these two viruses, differences among several homologous rna genome segments have been detected. the implication of the use of these techniques for characterization and analysis of recently i ... | 1984 | 6487199 |
| forms of leg abnormality observed in male broilers fed on a diet containing 12.5 percent rapeseed meal. | the incidence of leg abnormalities was studied in 216 male ross i broilers, fed for 10 weeks on a diet containing 12.5 per cent extracted rapeseed. regular serological examination showed that the birds remained free from mycoplasma gallisepticum, mycoplasma synoviae and avian reovirus throughout the period of investigation. post mortem examination and radiographs were performed when birds were culled due to leg deformities or at the end of the experiment. leg abnormalities were seen in 19.4 per ... | 1983 | 6635344 |
| a comparison of avian and mammalian cell cultures for the propagation of avian reovirus wvu 2937. | two avian and seven mammalian cell lines were evaluated for their application in propagating avian reovirus wvu 2937. cultures were compared for monolayer-formation time, support of viral replication, passages and postinfection time required for expression of cytopathic effect (cpe), type of cpe, and virus yield. cpe was observed on the first passage with infected egg yolk in primary chicken embryo kidney cells, primary through tertiary chicken embryo liver (cel) cells, and african green monkey ... | 1984 | 6721794 |
| in vitro characterization of an avian reovirus vaccine strain. | in vitro studies were performed to characterize the vaccine strain, designated p100, derived from the arthrogenic reovirus isolate, s1133, by cold adaptation. p100 appeared to be temperature sensitive, shown by a marked drop in titer and efficiency of plaquing after incubation at 41 degrees. studies indicated that genomic double-stranded rna and protein synthesis were severely restricted at the elevated temperature. differences in the growth behavior of p100 and s1133 at 37 degrees were also not ... | 1983 | 6845656 |
| characteristics and pathogenicity of two avian reoviruses isolated from chickens with leg problems. | two reoviruses identified as 172 and 176 were isolated from the hock of 2-to-3-week-old broiler breeders exhibiting leg problems. oral-ocular or intraplantar inoculation of day-old specific-pathogen-free or broiler chickens produced severe mortality (60-100%) within 2 to 6 days. the main lesions observed were tenosynovitis as well as necrosis and congestion of the liver, spleen, kidneys, and bursa of fabricius. | 1983 | 6847543 |
| polymorphism of the genomic rnas among the avian reoviruses. | the genome of avian reoviruses is comprised of 10 segments of double-stranded (ds)rna. analysis by polyacrylamide gel electrophoresis of the genomic rna from a small number of avian reoviruses has demonstrated a significant polymorphism in the migration pattern of the dsrna segments among different isolates. comparison of these patterns with that of the mammalian reovirus of serotype 1 has permitted calculation of the molecular weights of the avian dsrna species. | 1982 | 7119751 |
| avian reovirus polypeptides: analysis of intracellular virus-specified products, virions, top component, and cores. | avian reovirus-specified polypeptides can be separated into three size classes: large (lambda), medium (mu), and small (sigma), similar to those of the mammalian reoviruses. a nomenclature has been proposed to indicate the individual polypeptides within each size class by progressive alphabetical subscripts. three lambda polypeptides (lambda(a), lambda(b), and lambda(c)) are found in infectious viral particles and have molecular weights of 145,000, 130,000, and 115,000, respectively. all are pre ... | 1982 | 7143561 |
| characterization of a novel syncytium-inducing baboon reovirus. | a syncytium-inducing reovirus was recently isolated from brain homogenates of a baboon suffering from acute, progressive meningoencephalo myelitis. this baboon reovirus (brv) was classified as a member of the genus orthoreovirus, family reoviridae, on the basis of the characteristic capsid morphology and genome and protein profiles. we have assessed the relationship between brv and the other syncytium-inducing reoviruses in order to determine whether the emergence of this virus represents a host ... | 1995 | 7571448 |
| reovirus infection in chickens primes splenic adherent macrophages to produce nitric oxide in response to t cell-produced factors. | in this study, we examined the mechanisms by which avian reovirus infection of chickens depresses in vitro proliferative responses of spleen cells to t cell mitogens. we showed an enhanced production of nitric oxide (no) by phytohemagglutinin (pha)-stimulated spleen cells from reovirus-infected birds but not from virus-free birds. since macrophages are a primary source of no, we compared splenic adherent macrophages from virus-free and virus-exposed chickens. there was a fourfold increase in the ... | 1995 | 7656329 |
| preliminary studies of primary ostrich fibroblasts for the isolation of ratite viruses. | an ostrich egg at 21 days of development was used to propagate primary embryo cell cultures. primary cultures of skeletal muscle cells (for fibroblasts) were prepared by routine typsinization techniques. the ostrich embryo fibroblasts were tested for their ability to propagate stock avian viruses of infectious bronchitis virus, paramyxiovirus-1 (pmv-1), pmv-2, pmv-3, infectious bursal disease virus, quail bronchitis virus, avian reovirus, turkey coronavirus, and two ostrich-originating specimens ... | 1994 | 7702522 |
| avian reovirus sigma c protein contains a putative fusion sequence and induces fusion when expressed in mammalian cells. | the biological functions of the structural protein sigma c, from avian reovirus strain ram-1, were investigated in this study. a putative fusion peptide in sigma c was recognized in the deduced amino acid sequence by homology with pneumovirus fusion sequences, and it was thus postulated that this protein may be involved in the formation of syncytia in cells infected with ram-1. the sigma c gene was cloned and expressed in mammalian (cos7) cells and the sigma c protein was found to induce syncyti ... | 1995 | 7747439 |
| cloning, sequencing and expression of the s1 gene of avian reovirus. | the s1 genome segment of avian reovirus strain s1133 was cloned and completely sequenced. the sequence comprised 1636 bp with three distinct open reading frames (orfs), suggesting the gene was polycistronic in nature. the three orfs from 5' to 3' were predicted to encode polypeptides of 9.8, 3.8 and 34.9 kda, respectively. of the three orfs, only the third possessed the aug initiation codon in an optimum context for translation. the third orf-encoded protein, 326 amino acids in length, was expre ... | 1995 | 7782781 |
| the effect of microaerosolized hydrogen peroxide on bacterial and viral poultry pathogens. | the effect of microaerosolized h2o2 on bacterial and viral poultry pathogens was investigated. bacterial cultures and viruses were dried on sterile glass petri dishes and subjected to direct and indirect 5% (h2o2) microaerosol mist. in the trials using escherichia coli and staphylococcus aureus, there was complete inactivation following exposure to h2o2. using salmonella typhimurium, indirect exposure resulted in only partial inactivation whereas direct exposure to h2o2 gave complete inactivatio ... | 1994 | 7816725 |
| a serosurvey using enzyme-linked immunosorbent assay for antibodies against poultry pathogens in ostriches (struthio camelus) from zimbabwe. | horseradish peroxidase-conjugated goat anti-ostrich igg was raised and used in commercial enzyme-linked immunosorbent assay kits to detect antibodies reactive with 11 poultry pathogens in sera from 149 ostriches from nine farms around zimbabwe. antibodies were detected to turkey rhinotracheitis virus (99%), newcastle disease virus (23%), avian reovirus (19%), infectious bursal disease virus (15%), avian encephalomyelitis virus (15%), mycoplasma gallisepticum and/or m. synoviae (11%), reticuloend ... | 1994 | 7832718 |
| diseases and management of backyard chicken flocks in chitungwiza, zimbabwe. | to gather information on backyard chicken flocks in chitungwiza, an urban center in zimbabwe, 85 flock owners were interviewed. the mean flock size was 53 birds (range 1-650), and most birds were kept for meat, for either domestic consumption or local sale. mean age at slaughter was 12.4 weeks (range 8-24). none of the owners vaccinated their birds, and reported mortality rates were high (mean 25%), most commonly being associated with diseases causing eye and respiratory problems. most owners co ... | 1994 | 7832719 |
| endogenous enzymatic activities of the avian reovirus s1133: identification of the viral capping enzyme. | avian reovirus s1133 was shown to contain all the enzymatic activities required for the synthesis of mature viral transcripts, including a dsrna-dependent rna polymerase, a nucleoside triphosphate phosphohydrolase, an mrna guanylyltransferase, and two mrna methyltransferases. the virus used these enzymes both in vitro and in vivo to catalyze the synthesis of viral mrnas containing a type-1 cap at their 5' ends. incubation of reovirions with gtp led to the formation of an intermediate structure c ... | 1995 | 7856076 |
| restriction of avian reovirus in primary chicken embryo tendon cells. | upon infection of the gastrointestinal tract, some avian reovirus strains spread to multiple organs of their natural hosts, chickens, and establish persistent infections. one manifestation of chronic infection is the development of arthritis in the tendons of the chickens. in order to study events associated with persistent infections in the tendon, primary cultures of chick embryo tendon (cet) cells were infected with avian reovirus. the cet cells supported a noncytopathic infection for at leas ... | 1995 | 7871719 |
| analysis of the double-stranded rna genome segments among avian reovirus field isolates. | nine isolates of avian reovirus (arv) from both healthy birds and birds with different clinical illness and one commercially available vaccine strain were selected and characterized by analysis of the migration pattern of their genomic double-stranded rna (dsrna) segments following separation by polyacrylamide gel electrophoresis. different electropherotypes were observed and analyzed. the results show that the dsrna segments of arv were markedly polymorphic among isolates within the same seroty ... | 1994 | 7962256 |
| a comparison of single and repeated oral infection of chicks with two avian reoviruses. | groups of specific pathogen-free light hybrid chicks were inoculated with one dose or repeated doses on alternate days of avian reovirus strain r2 isolated from tenosynovitis, or strain 49/82, isolated from infectious stunting. strain 49/82 induced significant reductions in weight gain after infection by either method, as did strain r2 after repeated doses. neither virus induced clinical signs or gross lesions of stunting or tenosynovitis in the five weeks of observation. both viruses and method ... | 1994 | 7973100 |
| comparative analysis of virus-induced polypeptides of an avirulent and a virulent strain of avian reovirus. | ten avian reovirus-specific polypeptides, ranging in molecular weight from 32,000 to 145,000, were identified in chicken embryo fibroblasts infected with virulent and attenuated strains. time-course studies on the viral polypeptides indicated that all of these proteins could be detected as early as 16 hr postinfection (pi) for both strains of avian reoviruses. with the virulent strain 1733, protein production reached a plateau 24 hr pi, whereas with an attenuated strain s1133, production plateau ... | 1994 | 7980271 |
| comparison of the labeled avidin-biotin and the conventional enzyme-linked immunosorbent assay for detecting antibody to reovirus in chickens. | a labeled avidin-biotin enzyme-linked immunosorbent assay (lab-elisa) for detecting antibodies to avian reovirus (arv) in chicken sera was developed and compared with conventional elisa. purified arv, biotin-labeled rabbit anti-chicken igg conjugate, and horseradish peroxidase-labeled avidin were used in the lab-elisa. the two types of elisa had the similar ability to clearly distinguish arv-positive and -negative sera. furthermore, non-specific reactions with the two elisas against sera from ar ... | 1994 | 7989449 |
| characterization of a reovirus isolate from a rattle snake, crotalus viridis, with neurological dysfunction. | a virus isolate from the brain of a rattle snake with central nervous system (cns) symptoms was identified as a reovirus. the isolate did not agglutinate pig erythrocytes and was not neutralized by antisera against avian reovirus s1133 and mammalian reovirus type 3. the cytopathic effect in vero cells was characterized by formation of syncytial giant cells. electrophoretic analysis of the genome revealed 10 segments of dsrna. the isolate displayed characteristics distinct from avian and mammalia ... | 1994 | 7998838 |
| subgenomic s1 segments are packaged by avian reovirus defective interfering particles having an s1 segment deletion. | two subgenomic segments derived from the s1 genome segment (sgs1-1 and sgs1-2) were identified in avian reovirus defective interfering (di) particle preparations having an s1 segment deletion. both sgs1-1 and sgs1-2 were composed of double-stranded rna (dsrna) with an estimated size of 400 and 380 bp, respectively. their segment of origin was identified as the s1 by hybridization analysis. the subgenomic segments were associated with the virus fraction following cscl density gradient centrifugat ... | 1994 | 8079514 |
| protein coding assignment of avian reovirus strain s1133. | avian reovirus s1133 encodes 10 primary translation products, 8 of which are structural components of the viral particle and 2 of which are nonstructural proteins. the identity of the gene that codes for each of these polypeptides was determined by in vitro translation of denatured individual genome segments. | 1994 | 8084013 |
| chymotrypsin and trypsin sensitivities of avian reoviruses. | experiments were undertaken to examine the chymotrypsin sensitivity and trypsin sensitivity of 13 avian reoviruses, and to determine if there was any correlation with pathogenicity of some chicken reoviruses. a wide variation in the degree of sensitivity of avian reoviruses to chymotrypsin and trypsin was observed. overall, the infectivity of the 13 avian reoviruses for vero cells was markedly reduced by treatment with 0.01% chymotrypsin (the lowest concentration tested) while 0.5% trypsin signi ... | 1994 | 8143259 |
| viral validation of the manufacturing process of high purity albumin from placentas. | we report on the viral validation of an industrial purification process which is used to manufacture high purity human albumin from frozen placentas. this process has been used without any modification since 1980 except for a progressive increase in production scale to reach a capacity of 19 tons of placentas per day. the extraction purification process includes five alcohol manufacturing steps, some with strict conditions of alcohol concentration, acid ph, temperature and one including chlorofo ... | 1993 | 8174808 |
| antibody detection in matched chicken sera and egg-yolk samples by commercial enzyme-linked immunosorbent assay kits for newcastle disease virus, infectious bronchitis virus, infectious bursal disease virus, and avian reovirus. | elisa kits have been used to detect antibody in egg yolk. the major advantage eggs offer over blood samples is the ability to collect samples without compromising flock biosecurity. a disadvantage to using egg yolk over sera concerns the method of preparing yolk for antibody testing. the technique used in this study involved a simple dilution method with no mixing or extraction. to determine the adequacy of yolk samples to replace serum samples, a serum sample and the first six eggs were obtaine ... | 1993 | 8257378 |
| radioimmunoprecipitation of avian reovirus polypeptides using virus-specific igm and igg murine monoclonal and chicken polyclonal antibodies. | a simple and improved procedure for radioimmunoprecipitation (ripa) for the identification of major immunogenic proteins of avian reovirus using murine monoclonal and chicken polyclonal antibodies is described. bacterial proteins (staphylococcus aureus-protein a or streptococcus species-protein g) commonly used in ripa procedures lack reactivities with low avidity monoclonals belonging to immunoglobulin (ig)g or igm subtypes, as well as avian ig. hence we used an indirect approach utilizing spec ... | 1993 | 8320307 |
| chemiluminescent detection of infectious bursal disease virus with a pcr-generated nonradiolabeled probe. | a polymerase chain reaction (pcr)-generated digoxigenin-labeled nonradioactive oligonucleotide probe was developed and utilized in slot-blot hybridization coupled with chemiluminescence for the detection of infectious bursal disease virus (ibdv). the probe was prepared from the rna of the standard challenge strain (stc) of ibdv serotype 1 by reverse transcription followed by 2 pcr amplifications with 2 separate sets of primers. rna of stc viruses prepared from bursae infected with stc viruses wa ... | 1993 | 8389597 |
| identification of proteins encoded by avian reoviruses and evidence for post-translational modification. | twelve avian reovirus strain 176 proteins, 10 structural (lambda 1, lambda 2, lambda 3, mu 1, mu 2/mu 2c, sigma 1, sigma 2, sigma 3, and sigma 4), and 2 nonstructural (mu ns and sigma ns) were identified and characterized by electrophoretic analysis of purified virions and infected cell lysates. three of the identified proteins (mu 1, mu ns, and sigma 4) have not been previously described. in pulse-chase experiments, 10 of the proteins (lambda 1, lambda 2, lambda 3, mu 1, mu 2, mu ns, sigma 1, s ... | 1993 | 8438580 |
| avian reovirus proteins associated with neutralization of virus infectivity. | monoclonal antibodies against two virion proteins of the ram-1 strain of avian reovirus neutralized virus infectivity; antibody against a 124-kda (lambda b) protein caused broadly specific neutralization and antibody against a 39-kda (sigma c) protein caused neutralization of greater type-specificity. the neutralizing activity of the monoclonals also exhibited host cell specificity: antibodies against the lambda b protein inhibited virus infectivity in vero cells and not chicken kidney cells; on ... | 1993 | 8503182 |
| characterization of avian reovirus-induced cell fusion: the role of viral structural proteins. | cell fusion induced by avian reovirus was analyzed using virus strain fc and vero cells. one-step growth curves showed that cell fusion was directly associated with viral replication. cell fusion occurred most efficiently at basic ph (8.0-8.5) and fusion from without could not be demonstrated. actinomycin d, at low concentrations, increased cell fusion, and cycloheximide prevented cell fusion, indicating that viral protein(s) were responsible for the induction of cell fusion. immunofluorescence ... | 1993 | 8503184 |
| synergism between chicken anemia virus (cav) and avian reovirus following dual infection of 1-day-old chicks by a natural route. | one-day-old specific-pathogen-free white leghorn chicks were dually infected with the cux-1 isolate of chicken anemia virus (cav) and separate avian reovirus strains (s1133 or uchida) by an oral route. fourteen days after inoculation, chicks were bled, and packed cell volumes (pcvs) were determined. chicks were also weighted and examined for macroscopic changes to the bone marrow, thymus, and bursa of fabricius. the results obtained following dual inoculation of chicks with cav and reovirus were ... | 1995 | 8561738 |
| a comparative study of avian reovirus pathogenicity: virus spread and replication and induction of lesions. | this study examined the relationship of avian reovirus spread and replication to induction of lesions and the relevant role of the s1 segment encoding a virus-neutralizing antigen. one-day-old broiler chickens were infected via footpad or orally with two virus strains (883 and 176) that differ greatly in virulence and a reassortant (r44) that has the s1 segment from 176 and the remaining genome segments from 883. virus replication and histological lesions in various tissues (heart, liver, spleen ... | 1995 | 8561741 |
| turkey rhinotracheitis virus isolated from broiler chicken with swollen head syndrome in japan. | turkey rhinotracheitis (trt) virus was first isolated from a commercial broiler chicken with swollen head syndrome (shs) in japan. at the same time, newcastle disease virus (ndv), infectious bronchitis virus (ibv), avian reovirus (arv), escherichia coli (e.coli), morganella morganii, and proteus mirabilis were also isolated from the same broiler chicken. the presence of antibodies to trt virus was confirmed in the sera of 34-day-old chickens of the flock with shs, however the antibodies to trt v ... | 1995 | 8593307 |
| stages of marek's disease virus latency defined by variable sensitivity to interferon modulation of viral antigen expression. | cytokines in conditioned medium can suppress expression of viral internal antigens (via) in lymphocytes latently infected with marek's disease virus. in the present study, conditioned media produced by spleen cells stimulated with concanavalin a or by mixed-lymphocyte reaction had significantly greater (p < 0.05) via-suppressive activity with lymphocytes harvested from birds at 14 days post infection than with those collected at 7 days. this finding defines two stages during the latent period in ... | 1995 | 8604560 |
| the low ph-dependent entry of avian reovirus is accompanied by two specific cleavages of the major outer capsid protein mu 2c. | avian reoviruses are capable of inducing rapid and extensive syncytium formation, a process that occurs preferentially under conditions of neutral or alkaline ph. in order to ascertain whether the membrane fusion-inducing capability of avian reovirus confers a ph-independent entry mechanism on the virus, virus entry was investigated using internalization assays and several lysomotropic agents that inhibit endosomal acidification. the ability of avian reovirus to infect cells was severely restric ... | 1996 | 8623527 |
| intracellular posttranslational modifications of s1133 avian reovirus proteins. | avian reovirus s1133 specifies at least 10 primary translation products, eight of which are present in the viral particle and two of which are nonstructural proteins. in the work presented here, we studied the covalent modifications undergone by these translation products in the infected cell. the structural polypeptide mu2 was shown to be intracellularly modified by both myristoylation and proteolysis. the site-specific cleavage of mu2 yielded a large carboxy-terminal fragment and a myristoylat ... | 1996 | 8627773 |
| the low ph-dependent entry of avian reovirus is accompanied by two specific cleavages of the major outer capsid protein μ2c | avian reoviruses are capable of inducing rapid and extensive syncytium formation, a process that occurs preferentially under conditions of neutral or alkaline ph. in order to ascertain whether the membrane fusion-inducing capability of avian reovirus confers a ph-independent entry mechanism on the virus, virus entry was investigated using internalization assays and several lysomotropic agents that inhibit endosomal acidification. the ability of avian reovirus to infect cells was severely restric ... | 1996 | 8661373 |
| evidence for the multimeric nature and cell binding ability of avian reovirus sigma 3 protein. | it has been suggested that avian reovirus sigma 3 protein is analogous to sigma 1 trimer, the mammalian reovirus attachment protein. we have investigated the multimeric nature and cell binding ability of sigma 3 protein. the data presented here demonstrate that sigma 3 protein is a multimer in its undisrupted form as determined by sds-page in non-dissociating conditions. however, virion-associated sigma 3 protein and cos-7 cell-expressed protein behaved differently in sds-page, suggesting a need ... | 1996 | 8683208 |
| immunohistochemical detection of lymphocyte subpopulations in the tarsal joints of chickens with experimental viral arthritis. | we characterized the lymphocytes in the tarsal joint synovium of chickens inoculated with an arthrotropic strain of avian reovirus. cryostat sections of whole joints taken from 2 days to 35 days postinoculation were analyzed using monoclonal antibodies directed against b lymphocytes, t lymphocytes, and chicken ia antigen. plasma cells were morphologically identified using stained sections of whole joints. time-dependent changes were found in the type and number of positively staining cells. syno ... | 1996 | 8740704 |
| an antiviral effect of nitric oxide: inhibition of reovirus replication. | we have previously shown that macrophages from chickens infected with avian reovirus are primed to produce nitric oxide (no) in response to t cell cytokines and bacterial lipopolysaccharide (lps). we now show that no exerts potent antireovirus effects. reovirus replication was substantially reduced in a chicken macrophage cell line, hd11, induced to make no by stimulation with lps or conditioned medium from concanavalin a-stimulated spleen cells. the use of a competitive inhibitor of nitric oxid ... | 1996 | 8790884 |
| production and characterization of monoclonal antibodies against avian reovirus strain s1133. | monoclonal antibodies (mabs) were produced against the avian reovirus strain s1133. mabs were isotyped and used to develop diagnostic tests. splenocytes from immunized mice were screened by enzyme-linked immunosorbent assay (elisa). two hybridomas secreted mabs against avian reovirus s1133. one mab secreted igg1 and the other secreted igg2a. all mab light chains were kappa specificity of mabs was tested against four avian reovirus strains: s1133, 1733, co8, and 2408. strains s1133, 1733, and 240 ... | 1996 | 8790885 |
| avian reovirus-induced syncytium formation is independent of infectious progeny virus production and enhances the rate, but is not essential, for virus-induced cytopathology and virus egress. | the nonenveloped avian reoviruses represent a distinct antigenic subgroup of orthoreoviruses. unlike their mammalian counterparts, the avian reoviruses exhibit the unusual property of inducing rapid and extensive syncytium formation in cell cultures, a cytopathic effect more commonly associated with enveloped virus replication. while the syncytium-inducing capability of avian reovirus has been known for quite some time, the relationship between cell fusion and the virus replication cycle has not ... | 1996 | 8874506 |
| suppressor macrophages mediate depressed lymphoproliferation in chickens infected with avian reovirus. | a previous study indicated that spleens from reovirus-infected chickens contained macrophages that were primed to produce nitric oxide (no). the presence of these primed macrophages correlated with depressed in vitro t cell mitogenesis. the current studies indicated that splenic adherent macrophages from virus-exposed chickens inhibited concanavalin a (cona) induced proliferation of normal spleen cells. cona-stimulated spleen cells from uninfected chickens, but not virus-exposed chickens, produc ... | 1996 | 8941975 |
| protein architecture of avian reovirus s1133 and identification of the cell attachment protein. | there are a number of discrepancies in the literature regarding the protein composition of the avian reoviruses. the present study demonstrates that avian reovirus s1133 contains at least 10 proteins (lambdaa, lambdab, lambdac, mua, mub, mubc, mubn, sigmaa, sigmab, and sigmac). polypeptides mub, mubc, mubn, sigmab, and sigmac are components of the outer capsid layer of the virus, while lambdaa, lambdab, mua, and sigmaa are core polypeptides. protein lambdac is a component of both layers, extendi ... | 1997 | 8985323 |
| amplification, cloning and sequencing of the sigmac-encoded gene of avian reovirus. | the sigmac-encoding cdna of avian reovirus (arv) 1733 strain was amplified, cloned and sequenced using double nested polymerase chain reaction (pcr). the arv sigmac protein is a minor component of the outer capsid that induces type-specific neutralization antibodies. four overlapping sigmac-encoding cdna fragments were obtained. together, the four fragments represented the whole coding sequence. the nucleotide and deduced amino acid sequences of sigmac-encoded gene of u.s. (s1133 and 1733) and a ... | 1997 | 9015291 |
| molecular characterization of avian reoviruses using nested pcr and nucleotide sequence analysis. | a nested polymerase chain reaction (pcr) with subsequent nucleotide sequence analysis identified and differentiated avian reoviruses (arvs). pcr products amplified from the s1 gene segment of arv of usa isolates were 738 and 342 bp, respectively. pcr products were conformed by southern and dot blot hybridizations. the amplified cdna fragments were cloned into the puc18 vector and subjected to dna sequencing. the nucleotide and deduced amino acid sequences of four usa (s1133, 1733, 2408, and co8) ... | 1997 | 9186939 |
| characterization of a nonradioactive cloned cdna probe for detecting avian reoviruses. | avian reoviruses (arvs) cause important losses in the poultry industry. improved tests are needed for diagnosis of arv infections. a cdna library was prepared from the s1133 isolate of arv. ecori-adaptored cdna molecules were ligated into the plasmid puc19 and used to transform escherichia coli strain dh5 alpha mcr. one cdna clone was selected and designated hjp1. the hjp1 was labeled by random priming with digoxigenin-dutp. this cdna probe hybridized with the s1 gene fragment of the arv s1133 s ... | 1997 | 9201402 |
| in situ detection of reovirus in formalin-fixed, paraffin-embedded chicken tissues using a digoxigenin-labeled cdna probe. | an in situ hybridization (ish) technique using a digoxigenin (dig)-labeled cdna probe detected avian reovirus (arv) rna in formalin-fixed, paraffin-embedded chicken tissues. tissues were collected 3 and 10 days following inoculation with the r-2 or the s1133 strain of arv. the cdna clone hjp1, located on the s1 gene segment of the arv s1133 strain, was used to prepare a nonradioactive probe. the ish assay localized arv rna in infected tissues including heart, liver, intestine, pancreas, and tend ... | 1997 | 9201413 |
| immune response to avian reovirus in chickens and protection against experimental infection. | to assess the efficacy of the vaccination procedure and the effect of the transfer of maternal antibodies to progeny chickens on reovirus pathogenicity. | 1997 | 9247694 |
| characterization of the double-stranded rna genome segment s3 of avian reovirus. | the double-stranded rna genome segment s3 of avian reovirus (arv) s1133 was cloned following polyadenylation of both strands and cdna synthesis of s3 rna. the complete segment s3 nucleotide sequence was determined. s3 is 1196 base pairs long with one long open reading frame (orf). the orf possesses the aug initiation codon in an optimum context for translation and starts at the first initiation codon (residue 24) and extends for 367 codons, sufficient to encode a protein of the same size as the ... | 1997 | 9274822 |
| amplification of avian reovirus rna using the reverse transcriptase-polymerase chain reaction. | a reverse transcriptase-polymerase chain reaction method was developed for the detection of avian reovirus. the origin of primers was from the s1 gene of the avian reovirus genome. a reovirus-specific 532-base pair cdna product was amplified by these primers from six reference strains and 23 field isolates of avian reoviruses, but not from seven different avian pathogenic viruses and bacteria. as little as 1 pg of avian reovirus rna was detected using gel electrophoresis and southern blot hybrid ... | 1997 | 9356712 |
| experimental inoculation of mice with trypsin-resistant and trypsin-sensitive avian reoviruses. | groups of sucking swiss albino mice were inoculated by the intracerebral (i.c.), intraperitoneal (i.p.) or oral route with a trypsin-sensitive avian reovirus (tr1) or a trypsin-resistant (r2) reovirus. the viruses caused a number of effects, the most severe occurring after i.c. inoculation and the least after oral inoculation. they included incoordination and tremors, oiliness of the hair, and retarded growth. patterns of viral persistence in tissues were similar for the two viruses, with high t ... | 1997 | 9447485 |
| [reovirus infection of pheasants (phasianus colchicus)]. | in this case report we discribe clinic, pathology and diagnostic of an avian reovirus-infection in pheasants. the disease was observed 1993 in a flock of game-pheasants in the western part of turkey. of a live-stock of 100 animals, 27 were affected most of them being three to five months old. beside a general disorder, sick pheasants showed signs of shortness of breath as well as greenish, watery diarrhoea and died within a week. the pathologic findings were dominated by an extreme hepatopathia. ... | 1998 | 9587976 |
| identification and characterization of rna-binding activities of avian reovirus non-structural protein sigmans. | cytoplasmic extracts prepared from avian reovirus (arv) strain s1133-infected chicken embryo fibroblasts were examined for the presence of rna-binding proteins in order to identify and characterize arv rna-binding proteins. analysis of binding activity to poly(a)-sepharose indicated that infected cells contained significant amounts of a protein that co-migrated with arv protein sigmans present in total virus-infected cell extracts. determination of the n-terminal amino acid sequence of several p ... | 1998 | 9634083 |
| cloning and nucleotide sequencing of the s4 genome segment of avian reovirus s1133. | the sequence of rna genome segment s4 of the avian reovirus (arv) strain s1133 was determined. s4 rna is 1185 base pairs long and contains one open reading frame encoding a protein of 367 amino acid residues (40.6 kda), the similar size as the known s4 gene product (sigma ns), with a net charge of -1 at neutral ph. the s4 rna sequence possesses a pentanucleotide sequence ucauc at the 3'-terminus of its plus strand like in arv s1 and s3 segments and ten segments of mammalian reovirus (mrv). the p ... | 1997 | 9672610 |
| serological survey of viral pathogens in bean and white-fronted geese from germany. | sera from wild geese were tested for antibodies to selected viral pathogens at a resting site for wild waterfowl in germany. serum samples from both bean geese (anser fabalis) and white-fronted geese (anser albifrons) collected in october 1991 were examined using serological methods licensed for routine diagnosis in domestic poultry. of 130 sera tested, antibodies to several infectious agents were found including newcastle disease virus (45%), goose parvovirus (48%), avian reovirus (29%), and av ... | 1998 | 9706557 |
| detection of avian reovirus rna and comparison of a portion of genome segment s3 by polymerase chain reaction and restriction enzyme fragment length polymorphism. | a reverse transcription-polymerase chain reaction (rt-pcr) was established to amplify a 672-base pairs fragment on the segment s3 of avian reovirus (arv). the amplified fragments were detected in nine strains of arv as well as three tendon tissue specimens, indicating that the primer regions were well conserved. the rt-pcr was able to detect as low as 0.2 pg using an ethidium bromide stained gel. the detection limit could be enhanced further to 0.04 pg by hybridisation after southern transfer. t ... | 1998 | 9769066 |
| characterization of two avian reoviruses that exhibit strain-specific quantitative differences in their syncytium-inducing and pathogenic capabilities. | we previously proposed that the conservation of the nonessential syncytium-inducing phenotype among all reported avian reovirus (arv) isolates may reflect a mechanism for enhanced virus dissemination in vivo, which in turn could contribute to the natural pathogenicity of arv. direct testing of this hypothesis has been hampered by the lack of available virus strains with defined differences in their fusion-inducing capability. we now report on the characterization of two arv strains, arv-176 and ... | 1998 | 9792837 |
| association between the sigma c protein of avian reovirus and virus-induced fusion of cells. | monoclonal antibodies (mabs) against a 39 kda (sigma c) protein of the avian reovirus ram-1 strain inhibited virus-induced fusion of cells and the protein was expressed on the surface of infected cells. the fusion-inhibiting activity of the three mabs reacting with the sigma c protein suggest two putative epitopes were involved: one epitope recognised by antibody 6h1 and involved in fusion of both vero and ck cells and a second epitope recognised by antibody 1g1 involved in fusion of vero cells ... | 1999 | 10076520 |
| health evaluation of free-ranging rockhopper penguins (eudyptes chrysocomes) in argentina. | as part of annual colony counts in santa cruz province, argentina, a health survey of rockhopper penguins (eudyptes chrysocomes) was conducted in 1994. forty-five birds were examined during handling procedures, and blood and fecal samples were collected for laboratory analysis. all birds appeared to be in good condition. no ecto- or endoparasites were found. hematology, plasma chemistry, and plasma mineral levels were measured and correlated with the results of bacterial and viral serology. anti ... | 1999 | 10367640 |
| extensive sequence divergence and phylogenetic relationships between the fusogenic and nonfusogenic orthoreoviruses: a species proposal. | the orthoreoviruses can be divided into subgroups based on either their restricted host range or the unusual ability of certain members of this group of nonenveloped viruses to induce cell-cell fusion from within. phylogenetic relationships cannot be inferred based on these biological properties because fusogenic reoviruses are present in both the avian and mammalian subgroups. to address this issue, the complete nucleotide sequences of the three s-class genome segments encoding the major sigma- ... | 1999 | 10417266 |
| comparison of two molecular techniques for the detection of avian reoviruses in formalin-fixed, paraffin-embedded chicken tissues. | reverse transcription (rt) in situ polymerase chain reaction (pcr) and in situ hybridization (ish) techniques were used to detect the sigma c-encoded gene of avian reovirus (arv) in chicken tissue sections. the advantage of using in situ methods is to make more rapid and accurate diagnosis of arv infections. the sensitivity of these two techniques were compared. of the two techniques, the rt in situ pcr test was found to be more sensitive than ish and provided the rapid, sensitive, and specific ... | 1999 | 10471029 |
| identification of the sigma c-encoded gene of avian reovirus by nested pcr and restriction endonuclease analysis. | a nested reverse transcription (rt)-polymerase chain reaction with subsequent restriction endonuclease analysis was developed for identification of the sigma c-encoded gene of avian reoviruses (arv). pcr products derived from the sigma c-encoded gene of all tested arvs resulted in a specific dna band of 1023 bp, indicating that there were no apparent insertions or deletions in this region. amplification with the nested primer pairs s1m-s1n and s1p-s1n generated 330 and 239 bp, respectively. pcr ... | 1999 | 10488765 |
| nuclear proliferation in syncytia during avian reovirus replication. | cultured chick embryonic fibroblasts formed syncytia after infection with avian reovirus (arv) strain 58-132. mitotic figures were occasionally observed within the syncytia. in addition, many nuclei in the syncytia incorporated 5-bromo-2'-deoxyuridine (brdu), a dna replication marker, indicating that they were in the s-phase of the cell cycle. these observations suggested that the nuclei within arv-induced syncytia originated from nuclear endomitosis without cell division, as well as from cell f ... | 1999 | 10534008 |
| tissue tropism of avian reoviruses is genetically determined. | two genome segments, m2 and s1, were preferentially selected in reassortants isolated in vero cells. analysis with monoclonal antibodies (mabs) against ram-1 strain showed that the 39-kda protein encoded by the genome segment s1 contained epitopes involved in neutralisation of virus infectivity for both vero and chicken kidney (ck) cells. the 39-kda protein appeared to have two major epitopes that are attachment sites for cell receptors, one interacting only with ck cell receptors and the other ... | 1999 | 10543386 |
| synthesis in escherichia coli of avian reovirus core protein varsigmaa and its dsrna-binding activity. | the genome segment s2 of p6ian reovirus (arv) s1133 was cloned and sequenced. the entire s2 nucleotide sequence is 1325 bp long with one long open reading frame that encodes a protein of 415 amino acids, corresponding to varsigmaa, a major core protein of arv. s2 possesses a pentanucleotide, tcatc, at the 3'-terminus of its plus strand, common to other known genome segments of arv and to 10 genome segments of mammalian reovirus. amino acid sequence analysis revealed that varsigmaa contains a car ... | 2000 | 10612658 |
| possible involvement of the double-stranded rna-binding core protein sigmaa in the resistance of avian reovirus to interferon. | treatment of primary cultures of chicken embryo fibroblasts with a recombinant chicken alpha/beta interferon (rcifn) induces an antiviral state that causes a strong inhibition of vaccinia virus and vesicular stomatitis virus replication but has no effect on avian reovirus s1133 replication. the fact that avian reovirus polypeptides are synthesized normally in rcifn-treated cells prompted us to investigate whether this virus expresses factors that interfere with the activation and/or the activity ... | 2000 | 10627522 |
| optimal conditions for the growth, purification and storage of the avian reovirus s1133. | in spite of their importance as avian pathogens causing important losses in poultry farming, the biochemistry of avian reoviruses has been little investigated. in order to facilitate the handling of these agents in the laboratory, a study was carried out to establish the best conditions both for growing the avian reovirus s1133 in primary cultures of chicken embryo fibroblasts and for purification and storage of viral suspensions. the results indicate that the conditions used currently for the m ... | 2000 | 10716337 |
| characterization of avian reovirus non structural protein sigmans synthesized in escherichia coli. | the coding region of avian reovirus s1133 genomic segment s4, encoding the non structural protein sigmans, was inserted into expression vector pet28a and the protein was expressed in escherichia coli bl21(de3) as a fusion protein containing a c-terminal peptide with six tandem histidines (his-tag). the expressed protein (esigmans) consistent with the expected molecular size of the avian reovirus protein sigmans synthesized in infected cells was readily purified by his-bind resin. the esigmans wa ... | 2000 | 10773313 |
| the use of monoclonal antibody probes for the detection of avian reovirus antigens. | two monoclonal antibodies (mab), e9 and h3, prepared against avian reovirus (arv) s1133, were used in an immuno-dot assay to detect arv antigens from cell culture and from tendon tissue samples of chickens. the limit of viral antigens detected was 8 ng using both mab probes. the probes detected 10 arv isolates representing at least two serotypes or pathotypes. the results indicated that these probes had broad specificity. the probes, however, did not cross-react with viral antigens prepared from ... | 2000 | 10785286 |
| avian reovirus infections. | avian reoviruses are ubiquitous among poultry flocks. although infection is usually present without disease, reoviruses may occasionally be involved in several disease syndromes of which viral arthritis/tenosynovitis in chickens is the most important, particularly in broiler breeds. while reoviruses have been isolated from turkeys and several other species of birds with various conditions, the presence of the virus has been conclusively linked with disease in relatively few instances. in chicken ... | 2000 | 10935283 |
| oligomerization and cell-binding properties of the avian reovirus cell-attachment protein sigmac. | avian reovirus protein sigmac, the viral cell-attachment protein, is a minor component of the outer-capsid shell of the viral particle that is synthesized in small amounts in infected cells. we cloned the sigmac-encoding orf in vector pil-2f, expressed it in escherichia coli, and partially purified the resulting recombinant protein from inclusion bodies. rabbit polyclonal antibodies raised against the recombinant protein specifically recognized the viral polypeptide in elisa, immunoprecipitation ... | 2000 | 10964779 |
| the history of avian reovirus. | | 2000 | 11007012 |
| an enzyme-linked immunosorbent assay for the detection of antibody to avian reovirus by using protein sigma b as the coating antigen. | an enzyme-linked immunosorbent assay using the expressed protein sigma b as the coating antigen (sigma b-elisa) for detecting antibody to avian reovirus (arv) in chickens was developed and compared with a conventional elisa. both elisa s and a serum neutralisation (sn) test were used to test the sera from experimentally vaccinated and farm chickens. the sigma b-elisa could clearly distinguish the sn-positive and -negative sera in 38-week-old chickens. the correlation rate between sn and a sigma ... | 2000 | 11020359 |
| monoclonal antibodies against different epitopes of nonstructural protein sigmans of avian reovirus s1133. | ten monoclonal antibodies (mabs) were prepared against the nonstructural protein sigmans of avian reovirus s1133. eight of them were selected for two-way competitive binding assay after coupling with horseradish peroxidase. the results allowed the definition of three epitopes, designated a, b, and c. blocking assay of poly(a)-sepharose binding activity of sigmans with mabs indicated that mab recognizing epitope b was able to block poly(a) oligomer binding, suggesting that epitope b is involved i ... | 2001 | 11259199 |
| baculovirus expression of turkey coronavirus nucleocapsid protein. | the nucleocapsid (n) gene of turkey coronavirus (tcv) was amplified by reverse transcriptase-polymerase chain reaction, cloned, and expressed in the baculovirus expression system. a recombinant baculovirus containing the tcv n gene (rbtcv/n) was identified by polymerase chain reaction and expression of tcv n protein as determined by western immunoblot analysis. two tcv-specific proteins, 52 and 43 kda, were expressed by rbtcv/n; one of these proteins, p52, was comparable in size to native tcv n ... | 2001 | 11332474 |
| avian reovirus major mu-class outer capsid protein influences efficiency of productive macrophage infection in a virus strain-specific manner. | we determined that the highly pathogenic avian reovirus strain 176 (arv-176) possesses an enhanced ability to establish productive infections in hd-11 avian macrophages compared to avian fibroblasts. conversely, the weakly pathogenic strain arv-138 shows no such macrophagotropic tendency. the macrophage infection capability of the two viruses did not reflect differences in the ability to either induce or inhibit nitric oxide production. moderate increases in the arv-138 multiplicity of infection ... | 2001 | 11333882 |
| generation and genetic characterization of avian reovirus temperature-sensitive mutants. | there currently is little known about the genetic and biological functions of avian reovirus (arv), an atypical member of the family reoviridae and the prototype of all nonenveloped viruses that induce syncytia formation. in this study, we created arv temperature-sensitive (ts) mutants by chemical mutagenesis of arv strain 138. we developed a novel efficiency of lysis (eol) screening technique and used it and the classical efficiency of plating (eop) assay to identify 17 arv ts mutants. pairwise ... | 2001 | 11352672 |
| combined sequential treatment with interferon and dsrna abrogates virus resistance to interferon action. | many viruses have evolved mechanisms to resist the action of interferon (ifn). these include production of viral gene products that sequester double-stranded rna (dsrna) and of small helical rna. these potentially prevent activation of dsrna-dependent pathways of ifn action or block expression of cellular genes activated exclusively by dsrna that may contribute to the antiviral state. thus, dsrna might be rate limiting in the development of an ifn-mediated antiviral state. in support of this hyp ... | 2001 | 11440640 |
| isolation of a new serotype of avian reovirus associated with malabsorption syndrome in chickens. | this paper describes the isolation and identification of a novel class of reoviruses, the so-called enteric reovirus strains (ers). the pathogenicity, dissemination, induction of malabsorption syndrome (mas), reaction pattern with different monoclonal antibodies, and serotype properties are reported. upon screening of reoviruses in the field, it was observed that these reovirus strains were also present in other countries and were usually isolated from birds with mas. based on the data presented ... | 2001 | 11513255 |
| cases of swollen head syndrome in broiler chickens in greece. | from 50 commercial broiler flocks included in a study concerning respiratory disease, signs of swollen head syndrome (shs) were shown in eight. postmortem examination was performed in eight birds showing signs of shs from each flock. the trachea and head from each bird were collected for laboratory investigation. an enzyme-linked immunosorbent assay (elisa) was used for the detection of viral and avian mycoplasma antigens in the trachea, and bacteriologic examinations were performed from the inf ... | 2001 | 11569754 |
| sequence and phylogenetic analysis of the sigmaa-encoding gene of avian reovirus. | the full-length sigmaa-encoding gene nucleotide sequences (1251 bp) of ten avian reovirus (arv) field-isolates and three vaccine strains were determined and analyzed to study the degree of genetic divergence and evolution. strains were isolated over a 23-year period from different hosts, pathotypes, and geographic locations. a phylogenetic tree constructed from variation in the sigmaa nucleotide sequences among arv isolates showed that taiwanese isolates from different dates of isolation were gr ... | 2001 | 11576636 |
| restricted growth of avirulent avian reovirus strain 2177 in macrophage derived hd11 cells. | the replication of two pathotypes of avian reovirus, 1733 and 2177 in transformed chicken lymphoid and myeloid cell lines was examined, showing that only the macrophage cell line, hd11, supports replication. the virulent strain 1733 causes a lytic infection producing 100-1000 fold more virus than the avirulent strain 2177. cells infected with strain 2177 display delayed viral rna and protein synthesis as well as a suppressed expression of the major capsid protein mub. these features may contribu ... | 2001 | 11682129 |
| sequential partially overlapping gene arrangement in the tricistronic s1 genome segments of avian reovirus and nelson bay reovirus: implications for translation initiation. | previous studies of the avian reovirus strain s1133 (arv-s1133) s1 genome segment revealed that the open reading frame (orf) encoding the final sigmac viral cell attachment protein initiates over 600 nucleotides distal from the 5' end of the s1 mrna and is preceded by two predicted small nonoverlapping orfs. to more clearly define the translational properties of this unusual polycistronic rna, we pursued a comparative analysis of the s1 genome segment of the related nelson bay reovirus (nbv). se ... | 2002 | 11752152 |
| subunit composition and conformational stability of the oligomeric form of the avian reovirus cell-attachment protein sigmac. | previous work has shown that the avian reovirus cell-attachment sigma c (sigmac) protein is a multimer. in the first part of this study the oligomerization state of intracellularly synthesized sigmac was analysed by different approaches, including sds-page, chemical cross-linking, sedimentation and gel filtration analysis. all these approaches indicated that protein sigmac in its native state is a homotrimer. in the second part of the present work we investigated the effect of different factors ... | 2002 | 11752709 |
| the s4 genome segment of baboon reovirus is bicistronic and encodes a novel fusion-associated small transmembrane protein. | we demonstrate that the s4 genome segment of baboon reovirus (brv) contains two sequential partially overlapping open reading frames (orfs), both of which are functional in vitro and in virus-infected cells. the 15-kda gene product (p15) of the 5"-proximal orf induces efficient cell-cell fusion when expressed by itself in transfected cells, suggesting that p15 is the only viral protein required for induction of syncytium formation by brv. the p15 protein is a small, hydrophobic, basic, integral ... | 2002 | 11836390 |
| development of an elisa for detection of antibodies to avian reovirus in chickens. | an enzyme-linked immunosorbent assay (elisa) using the expressed sigmac and sigmab proteins which induce neutralizing antibodies as the coating antigen (sigmac-sigmab-elisa) for the detection of antibodies to avian reovirus in chickens was developed and compared with serum neutralization and conventional elisa tests. these assays were used to examine the sera from chickens vaccinated experimentally and farm chickens. the correlation rate between serum neutralization and a sigmac-sigmab-elisa was ... | 2002 | 11879701 |
| the avian reovirus genome segment s1 is a functionally tricistronic gene that expresses one structural and two nonstructural proteins in infected cells. | the avian reovirus s1 gene contains three partially overlapping, out-of-phase open reading frames (orfs) that the highly conserved in all avian reovirus strains examined to date. the three s1 orfs of the avian reovirus strain s1133 were individually expressed in bacterial cells, and their purified translation products used as antigens to raise specific polyclonal antibodies. with these antibodies we were able to demonstrate that all three s1 orfs from different avian reovirus strains are transla ... | 2001 | 11883183 |
| evidence of nucleotidyl phosphatase activity associated with core protein sigma a of avian reovirus s1133. | both avian reovirus core protein sigma a purified from virus-infected cell extracts and the purified bacterially expressed protein sigma a (e sigma a) were characterized for their nucleoside triphosphate (ntp) hydrolysis activity by thin-layer chromotography. protein sigma a from both preparations has a nonspecific nucleotidyl phosphatase activity that hydrolyzes four types of ntp to their corresponding nucleoside di- and monophosphates and free phosphate. the divalent cation requirement for thi ... | 2002 | 11886258 |
| modification of late membrane permeability in avian reovirus-infected cells: viroporin activity of the s1-encoded nonstructural p10 protein. | infection of chicken embryo fibroblasts by avian reovirus induces an increase in the permeability of the host plasma membrane at late, but not early, infection times. the absence of permeability changes at early infection times, as well as the dependence of late membrane modification on both viral protein synthesis and an active exocytic route, suggest that a virus-encoded membrane protein is required for avian reovirus to permeabilize cells. further studies revealed that expression of nonstruct ... | 2002 | 11893756 |
| isolation of a reovirus from poult enteritis and mortality syndrome and its pathogenicity in turkey poults. | poult enteritis and mortality syndrome (pems) is an acute, infectious intestinal disease of turkey poults, characterized by high mortality and 100% morbidity, that decimated the turkey industry in the mid-1990s. the etiology of pems is not completely understood. this report describes the testing of various filtrates of fecal material from control and pems-affected poults by oral inoculation into poults under experimental conditions, the subsequent isolation of a reovirus, arv-cu98, from one of t ... | 2002 | 11922348 |
| experimental reproduction of malabsorption syndrome with different combinations of reovirus, escherichia coli, and treated homogenates obtained from broilers. | attempts to reproduce malabsorption syndrome (mas) by oral inoculation with several different combinations including intestinal homogenate, reovirus, and hemolytic escherichia coli obtained from mas-affected chickens and intestinal homogenate from healthy chickens (healthy homogenate) were performed in 1-day-old specific-pathogen-free (spf) broilers. the mas homogenate, serving as a positive control, induced weight gain depression and intestinal lesions such as cystic crypts of lieberkuhn, villu ... | 2002 | 11924604 |