| 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 |
| 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 |
| muscovy duck reovirus sigmac protein is atypically encoded by the smallest genome segment. | although muscovy duck reovirus (drv) shares properties with the reovirus isolated from chicken, commonly named avian reovirus (arv), the two virus species are antigenically different. similar to the drv sigmab-encoded gene (1201 bp long) previously identified, the three other double-stranded rna small genome segments of drv have been cloned and sequenced. they were 1325, 1191 and 1124 bp long, respectively, and contained conserved terminal sequences common to arvs. they coded for single expressi ... | 2002 | 11961275 |
| diarrhea-inducing activity of avian rotavirus nsp4 glycoproteins, which differ greatly from mammalian rotavirus nsp4 glycoproteins in deduced amino acid sequence in suckling mice. | avian rotavirus nsp4 glycoproteins expressed in escherichia coli acted as enterotoxins in suckling mice, as did mammalian rotavirus nsp4 glycoproteins, despite great differences in the amino acid sequences. the enterotoxin domain of po-13 nsp4 exists in amino acid residues 109 to 135, a region similar to that reported in sa11 nsp4. | 2002 | 11992013 |
| isolation and characterization of a reovirus from common eiders (somateria mollissima) from finland. | samples of brain, intestine, liver, lung, spleen, and bursa of fabricius were collected from five common eider (somateria mollissima) duckling carcasses during a die-off in the western gulf of finland (59 degrees 50'n, 23 degrees 15'e) in june 1996. no viral activity was observed in specific-pathogen-free chicken embryos inoculated with tissue suspensions, but samples of bursa of fabricius from three birds were positive when inoculated into muscovy duck (cairina moschata) embryo fibroblasts. the ... | 2002 | 12061662 |
| reovirus infection in psittacine birds (psittacus erithacus): morphologic and immunohistochemical study. | in this paper we report on an outbreak of reovirus, herpesvirus (pacheco disease), and/or mycosis infection (aspergillus spp. and zygomyces spp.) affecting a batch of young african grey parrots (psittacus erithacus), with 80% morbidity and 30% mortality. study material was taken from five birds (four dead and one euthanatized) with a range of clinical symptoms (depression, diarrhea, respiratory symptoms). diagnosis was confirmed by immunohistochemical detection of avian reovirus, electron micros ... | 2002 | 12061663 |
| avian reoviruses cause apoptosis in cultured cells: viral uncoating, but not viral gene expression, is required for apoptosis induction. | the cytopathic effect evidenced by cells infected with avian reovirus s1133 suggests that this virus may induce apoptosis in primary cultures of chicken embryo fibroblasts. in this report we present evidence that avian reovirus infection of cultured cells causes activation of the intracellular apoptotic program and that this activation takes place during an early stage of the viral life cycle. the ability of avian reoviruses to induce apoptosis is not restricted to a particular virus strain or t ... | 2002 | 12133997 |
| baculovirus-expressed muscovy duck reovirus sigmac protein induces serum neutralizing antibodies and protection against challenge. | recombinant baculoviruses with sigmac- or sigmab-encoding gene from muscovy duck reovirus (drv) were constructed. western-blot analysis showed that sigmac was more immunoreactive than sigmab. vaccination of spf ducks with two injections, 3 weeks apart, of emulsions containing sigmac or sigmac + sigmab elicited drv-specific neutralizing antibodies. following challenge, vaccination partially--or even totally in some cases--prevented the appearance of clinical symptoms. moreover, immunization reduc ... | 2002 | 12163262 |
| mycophenolic acid inhibits avian reovirus replication. | avian reoviruses (arv) are economically important pathogens, especially in the poultry industry, where they cause viral arthritis and tenosynovitis. mycophenolic acid (mpa) is an inhibitor of inosine monophosphate dehydrogenase (mainly used clinically for immunosuppression) that inhibits the replication of several viruses. we demonstrate in this study that mpa also is capable of inhibiting arv replication in qm5 quail fibrosarcoma cells. the selectivity index of mpa in qm5 cells was determined a ... | 2004 | 15451179 |
| sequence analysis of the s3 gene from a turkey reovirus. | the deduced sigma-2 protein sequence from the s3 gene segment of a novel turkey reovirus, designated nc98, isolated from the bursa of birds exhibiting poult enteritis and mortality syndrome was determined. the isolate, serologically distinct from other avian reoviruses, was isolated in turkey embryo kidney cells and rna was purified for cdna synthesis. oligonucleotide primers were designed based on conserved avian s3 nucleotide sequence data. the nc98 s3 open reading frame comprised 1,101 base p ... | 2002 | 12206313 |
| a reovirus challenge model applicable in commercial broilers after live vaccination. | the efficacy of live reovirus vaccines may be determined by challenge via the foot pad route 3 to 4 weeks after vaccination. swelling and discoloration in the foot pad and shank are scored for a period of 14 days. the major disadvantages of this challenge model are the subjective judgement of gross foot pad and/or shank lesions, that it is very difficult to induce lesions in broilers, and that it causes animal suffering. other reovirus challenge models are based on reisolation of the virus from ... | 2002 | 12425788 |
| application of rt-pcr for the detection of avian reovirus contamination in avian viral vaccines. | an efficient procedure for the detection of avian reovirus (arv)-specific rna sequences in veterinary immunological medicinal products using reverse transcriptase polymerase chain reaction (rt-pcr) is described. four arv vaccine strains (1133, 1733, 2408 and olson wvu2937), two atcc strains (vr826 and vr856) as well as several arv field isolates obtained from domestic, wild and pet birds could be easily detected with s2- and s4-specific primers. the identity of the amplified fragments was confir ... | 2005 | 15620400 |
| interactions of poult enteritis and mortality syndrome-associated reovirus with various cell types in vitro. | an avian reovirus, arv-cu98, has recently been isolated from poults experiencing poult enteritis and mortality syndrome (pems). to further understand arv-cu98 and its role in pems, the current study investigates interactions of arv-cu98 with various cell types in vitro. when macrophages, b cells, t cells, and liver cells of chicken or turkey origin were co-incubated with arv-cu98, only cells of liver origin demonstrated cytopathic effects, the presence of viral antigen, and reduced metabolic act ... | 2002 | 12455593 |
| characterization of monoclonal antibodies against avian reovirus s1133 protein sigmaa synthesized in escherichia coli. | monoclonal antibodies (mabs) were prepared against avian reovirus s1133 protein sigmaa (esigmaa) synthesized in escherichia coli. mabs were characterized and used to develop a diagnostic test. ten mabs were selected for competitive binding assay following coupling with horseradish peroxidase. the results indicated that these mabs delineated two epitopes i and ii of esigmaa. an immuno-dot binding assay was used to detect the effect of denaturation on antibody recognition of the epitopes. all mabs ... | 2003 | 12477645 |
| 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 |
| evidence that avian reovirus sigmaa protein is an inhibitor of the double-stranded rna-dependent protein kinase. | the results of a previous study demonstrated that avian reovirus is highly resistant to the antiviral effects of interferon and suggested that the double-stranded rna (dsrna)-binding sigmaa protein might play an important role in that resistance. to gather more evidence on the interferon-inhibitory activity of sigmaa protein, its gene was cloned into the prokaryotic maltose-binding protein (mbp) gene fusion vector pmalc and into the recombinant vaccinia virus wrs2. the two recombinant sigmaa pro ... | 2003 | 12771434 |
| enteropathogenicity of dutch and german avian reoviruses in spf white leghorn chickens and broilers. | the enteropathogenicity of avian reoviruses (arvs), isolated from chickens affected with malabsorption syndrome (mas) from the netherlands and germany was studied. in the first trial seven different arvs isolated from mas cases were inoculated in 1-day-old specific pathogenic free (spf) white leghorns. the pathogenicity was compared with 2 arvs isolated from cases of tenosynovitis, namely reference strain s1133 and a dutch strain. although a difference in the severity of the clinical disease was ... | 2003 | 12791238 |
| antibody responses against avian reovirus nonstructural protein sigmans in experimentally virus-infected chickens monitored by a monoclonal antibody capture enzyme-linked immunosorbent assay. | crude antigen preparations from avian reovirus (arv)-infected chicken embryo fibroblasts (sigmans) or from bacterially expressed protein sigmans (esigmans) were captured by monoclonal antibody 1e1(mab 1e1) against arv nonstructural protein sigmans immobilized on the elisa plates and were used as the mab capture elisa for antibody detection. sixty one-week-old specific pathogenic free (spf) chickens were divided into six groups and were vaccinated with live or inactivated arv vaccine preparations ... | 2004 | 15046956 |
| effect of in ovo administered reovirus vaccines on immune responses of specific-pathogen-free chickens. | we investigated the effect of in ovo administered reovirus vaccines on the immune responses of specific-pathogen-free chickens. t-cell mitogenic responses to concanavalin a were numerically lower at 9 and 12 days of age and significantly lower at 6 days of age in birds vaccinated with a commercial reovirus vaccine compared with unvaccinated birds or birds vaccinated with an experimental reovirus-antibody complex vaccine. there were no significant differences in proportions of subpopulations of h ... | 2004 | 15077821 |
| hematology, plasma biochemistry, and serosurvey for selected infectious agents in southern giant petrels from patagonia, argentina. | in conjunction with reproductive and feeding ecology studies on southern giant petrels (sgp, macronectes giganteus) blood samples were collected for baseline health evaluations. twenty-five adult sgp from a breeding colony in chubut, argentina, were sampled during two consecutive breeding seasons, 1999-2000 (n = 15) and 2000-01 (n = 10). values for hematology, plasma biochemistry, and minerals are described for 20 birds in apparent good physical condition. a serologic survey of exposure to selec ... | 2003 | 12910764 |
| palmitoylation, membrane-proximal basic residues, and transmembrane glycine residues in the reovirus p10 protein are essential for syncytium formation. | avian reovirus and nelson bay reovirus are two unusual nonenveloped viruses that induce extensive cell-cell fusion via expression of a small nonstructural protein, termed p10. we investigated the importance of the transmembrane domain, a conserved membrane-proximal dicysteine motif, and an endodomain basic region in the membrane fusion activity of p10. we now show that the p10 dicysteine motif is palmitoylated and that loss of palmitoylation correlates with a loss of fusion activity. mutational ... | 2003 | 12941885 |
| safety and efficacy of an experimental reovirus vaccine for in ovo administration. | a commercial reovirus vaccine alone or experimental reovirus vaccine plus antibody complex were inoculated into 18-day-old specific pathogen free (spf) broiler embryos at 0.1 of the recommended chick dose. the following groups were used: group 1a was not vaccinated or challenged; group 1b was not vaccinated, but was challenged with virulent reovirus; group 2 received the vaccine complexed with 1/4 dilution of antiserum; group 3 received the vaccine with 1/8 dilution of antiserum; group 4 receive ... | 2003 | 14708991 |
| structural organization of avian retrovirus integrase in assembled intasomes mediating full-site integration. | retrovirus preintegration complexes (pic) purified from virus-infected cells are competent for efficient concerted integration of the linear viral dna ends by integrase (in) into target dna (full-site integration). in this report, we have shown that the assembled complexes (intasomes) formed in vitro with linear 3.6-kbp dna donors possessing 3'-oh-recessed attachment (att) site sequences and avian myeloblastosis virus in (4 nm) were as competent for full-site integration as isolated retrovirus p ... | 2004 | 14990573 |
| structural and functional properties of an unusual internal fusion peptide in a nonenveloped virus membrane fusion protein. | the avian and nelson bay reoviruses are two of only a limited number of nonenveloped viruses capable of inducing cell-cell membrane fusion. these viruses encode the smallest known membrane fusion proteins (p10). we now show that a region of moderate hydrophobicity we call the hydrophobic patch (hp), present in the small n-terminal ectodomain of p10, shares the following characteristics with the fusion peptides of enveloped virus fusion proteins: (i) an abundance of glycine and alanine residues, ... | 2004 | 14990700 |
| avian reovirus sigmac protein induces apoptosis in cultured cells. | the avian reovirus (arv) infection is associated with various disease conditions in poultry. however, the pathogenesis mechanisms are poorly characterized. in the present study, we clearly demonstrated that the sigmac of arv s1133 strain induced apoptosis in both bhk-21 and vero cells. five kinds of assays for apoptosis were used in analyzing arv-infected bhk-21 and vero cells: (1) assay for dna ladders, (2) elisa detection of cytoplasmic histone-associated dna fragments, (3) nuclear staining wi ... | 2004 | 15033566 |
| host-dependent type 1 cytokine responses driven by inactivated viruses may fail to default in the absence of il-12 or ifn-alpha/beta. | replicating viruses generally induce type 1 immune responses, with high interferon (ifn)-gamma levels and antibodies of the igg2a isotype. in the present study we demonstrate the intrinsic ability of non-replicating virions to induce comparable immune responses in the notable absence of any adjuvant. injection of inactivated pseudorabies virus, an alphaherpesvirus, by various routes into mice resulted in the generation of t helper (th) 1 type immune response. co-delivery of inactivated pseudorab ... | 2004 | 15039522 |
| cell-cell fusion induced by the avian reovirus membrane fusion protein is regulated by protein degradation. | the p10 fusion-associated small transmembrane protein of avian reovirus induces extensive syncytium formation in transfected cells. here we show that p10-induced cell-cell fusion is restricted by rapid degradation of the majority of newly synthesized p10. the small ectodomain of p10 targets the protein for degradation following p10 insertion into an early membrane compartment. paradoxically, conservative amino acid substitutions in the p10 ectodomain hydrophobic patch that eliminate fusion activ ... | 2004 | 15140997 |
| a molecular dynamics study of reovirus attachment protein sigma1 reveals conformational changes in sigma1 structure. | molecular dynamics simulations were performed using the recently determined crystal structure of the reovirus attachment protein, sigma1. these studies were conducted to improve an understanding of two unique features of sigma1 structure: the protonation state of asp(345), which is buried in the sigma1 trimer interface, and the flexibility of the protein at a defined region below the receptor-binding head domain. three copies of aspartic acids asp(345) and asp(346) cluster in a solvent-inaccessi ... | 2004 | 15189844 |
| development of a quantitative light cycler real-time rt-pcr for detection of avian reovirus. | a robust, ultrasensitive, and accurate quantitative assay was developed for avian reovirus (arv) with the light cycler sybr green-based real-time reverse transcription-pcr (real-time lc rt-pcr). the assay exhibited high specificity as all negative controls and other avian pathogens, such as newcastle disease virus (ndv), infectious bronchitis virus (ibv), infectious bursal disease virus (ibdv), avian influenza virus (aiv), and mycoplasma synovia (ms), failed to show any positive detection. a min ... | 2006 | 16300834 |
| avian reovirus morphogenesis occurs within viral factories and begins with the selective recruitment of sigmans and lambdaa to microns inclusions. | we have recently shown that the avian reovirus non-structural protein microns forms cytoplasmic inclusions in transfected cells and recruits sigmans to these structures. in the present study we further demonstrate that microns mediates the association of the major core protein lambdaa, but not of sigmaa or sigmac, with inclusions, indicating that the recruitment of viral proteins into avian reovirus factories has specificity. thus, some proteins appear to be initially recruited to factories by a ... | 2004 | 15276829 |
| expression of avian reovirus sigmac protein in transgenic plants. | avian reovirus (arv) structural protein, sigmac encoded by s1 genome segment, is the prime candidate to become a vaccine against arv infection. two plant nuclear expression vectors with expression of sigmac-encoding gene driven by camv 35s promoter and rice actin promoter were constructed, respectively. agrobacterium containing the s1 expression constructs were used to transform alfalfa, and transformants were selected using hygromysin. the integration of s1 transgene in alfalfa chromosome was c ... | 2006 | 16488486 |
| rapid characterization of avian reoviruses using phylogenetic analysis, reverse transcription-polymerase chain reaction and restriction enzyme fragment length polymorphism. | a reverse transcription-polymerase chain reaction is described, which amplified the full-length sigmac-encoding and sigmans-encoding genes of avian reovirus (arv). dna fragments of 1022 and 1152 base pairs were amplified among arv isolates, respectively, indicating that there were no apparent deletions or insertions in these regions. fragments amplified from vaccine strains and field isolates were digested with five different restriction enzymes bcn i, hae iii, taq i, dde i, and hinc ii, respect ... | 2004 | 15276984 |
| the influence of reovirus sigma c protein diversity on vaccination efficiency. | avian reovirus (arv) is a disease agent that causes economic losses in the poultry industry. the available vaccines do not confer full protection. one possible reason is the existence in the field of many virulent serotypes with no cross protection. several arv strains have been isolated in israel in the last few years. in this study, we investigated the diversity of the sigma c protein of arv because this is the most variable protein in the virus and it induces the production of neutralizing an ... | 2004 | 15283414 |
| cloning, expression, and characterization of avian reovirus guanylyltransferase. | we have cloned and sequenced the l3 genome segment of avian reovirus strain 1733, which specifies the viral guanylyltransferase protein, lambdac. the l3 gene is 3907 nucleotides long and encodes, in a single large open-reading frame, a polypeptide of 1285 amino acid residues, with a calculated m(r) of 142.2 kda. expression of this gene in a baculovirus/insect cell system produced a recombinant protein that comigrated with reovirion lambdac and reacted with anti-reovirus polyclonal serum in a wes ... | 2002 | 12069527 |
| development of a multiplex pcr for detection of avian adenovirus, avian reovirus, infectious bursal disease virus, and chicken anemia virus. | a multiplex polymerase chain reaction (mpcr) was developed and optimized for the simultaneous detection and differentiation of avian reovirus (arv), avian adenovirus group i (aav-i), infectious bursal disease virus (ibdv), and chicken anemia virus (cav). four sets of specific oligonucleotide primers were used in this test for arv, aav-i, ibdv, and cav. the mpcr dna products were visualized by gel electrophoresis and consisted of fragments of 365 bp for ibdv, 421 bp for aav-i, 532 bp for arv, and ... | 2004 | 15294316 |
| avian reovirus temperature-sensitive mutant tsa12 has a lesion in major core protein sigmaa and is defective in assembly. | members of our laboratory previously generated and described a set of avian reovirus (arv) temperature-sensitive (ts) mutants and assigned 11 of them to 7 of the 10 expected recombination groups, named a through g (m. patrick, r. duncan, and k. m. coombs, virology 284:113-122, 2001). this report presents a more detailed analysis of two of these mutants (tsa12 and tsa146), which were previously assigned to recombination group a. the capacities of tsa12 and tsa146 to replicate at a variety of temp ... | 2004 | 15452234 |
| phylogenetic analysis of the sigma 2 protein gene of turkey reoviruses. | the open reading frame of the s3 segment encoding the sigma2 protein of four turkey reovirus field isolates was analyzed for sequence heterogeneity. the turkey reoviruses we present here have a 97% amino acid identity to turkey nc 98. the s3 nucleotide and amino acid sequence similarity was < or =61% and 78%-80%, respectively, when compared to the chicken reovirus isolates. comparison of amino acid sequences from chickens and turkeys with that of a duck isolate revealed a 53% and 55% similarity, ... | 2004 | 15529990 |
| epitope mapping and functional analysis of sigma a and sigma ns proteins of avian reovirus. | we have previously shown that avian reovirus (arv) sigmaa and sigmans proteins possess dsrna and ssrna binding activity and suggested that there are two epitopes on sigmaa (i and ii) and three epitopes (a, b, and c) on sigmans. to further define the location of epitopes on sigmaa and sigmans proteins and to further elucidate the biological functions of these epitopes by using monoclonal antibodies (mabs) 62, 1f9, h1e1, and 4a123 against the arv s1133 strain, the full-length and deletion fragment ... | 2005 | 15680423 |
| the second open reading frame of the avian reovirus s1 gene encodes a transcription-dependent and crm1-independent nucleocytoplasmic shuttling protein. | it was previously shown that the second open reading frame of the avian reovirus s1 gene encodes a 146-amino-acid nonstructural protein, designated p17, which has no known function and no sequence similarity to other known proteins. the results presented in this report demonstrate that p17 accumulates in the nucleoplasm of infected and transfected cells. an examination of the deduced amino acid sequence of p17 revealed the presence of a putative monopartite nuclear localization signal (nls) betw ... | 2005 | 15681417 |
| characterization of the nucleic acid-binding activity of the avian reovirus non-structural protein sigma ns. | the avian reovirus non-structural protein sigma ns has previously been shown to bind single-stranded (ss) rna in vitro in a sequence-independent manner. the results of the present study further reveal that sigma ns binds poly(a), poly(u) and ssdna, but not poly(c), poly(g) or duplex nucleic acids, suggesting that sigma ns has some nucleotide-sequence specificity for ssrna binding. the current findings also show that sigma ns is present in large ribonucleoprotein complexes in the cytoplasm of avi ... | 2005 | 15784910 |
| classification of dutch and german avian reoviruses by sequencing the sigma c protein. | we have amplified, cloned and sequenced (part of) the open reading frame of the s1 segment encoding the sigma c protein of avian reoviruses isolated from chickens with different disease conditions in germany and the netherlands during 1980 up to 2000. these avian reoviruses were analysed phylogenetically and compared with sequences of avian reoviruses in the genbank database. the avian reoviruses could be grouped in 5 different genotyping clusters and this classification was identical when the s ... | 2003 | 12657212 |
| pcr for the identification and differentiation of histomonas meleagridis, tetratrichomonas gallinarum and blastocystis spp. | in the present investigation pcr assays were developed for the rapid detection and differentiation of two poultry flagellates: histomonas meleagridis and tetratrichomonas gallinarum as well as the protozoan microorganism: blastocystis spp. the nucleotide sequences of the small subunit ribosomal rnas were used for primer construction obtaining fragments which vary in size for each microorganism. the established pcrs were able to detect dna obtained from one microorganism of t. gallinarum and blas ... | 2006 | 16920265 |
| sequence and phylogenetic analysis of p10- and p17-encoding genes of avian reovirus. | avian reovirus (arv) causes viral arthritis, chronic respiratory diseases, and malabsorption syndrome. the p10 protein is a viroporin and induces cell fusion, whereas the biological function of p17 protein is completely unknown. in this study, the nucleotide sequences of the p10- and p17-encoding genes from 17 field isolates and vaccine strains of arv isolated over a 23-year period from distinct geographic locations were analyzed to define phylogenetic profiles and to study sequence variability ... | 2005 | 15839410 |
| multiplex real-time reverse transcription-polymerase chain reaction for the detection of three viruses associated with poult enteritis complex: turkey astrovirus, turkey coronavirus, and turkey reovirus. | poult enteritis complex (pec) is an economically important disease of young turkeys characterized by diarrhea, poor weight gain, and, in some cases, high mortality. although pec is considered to be a polymicrobial disease, numerous viruses, including turkey coronavirus (tcv), turkey astrovirus type 2 (tastv-2), and avian reoviruses (arvs), have been associated with pec-like disease. real-time reverse transcription-polymerase chain reaction (rrt-pcr), a highly sensitive and specific detection met ... | 2005 | 15839418 |
| assignment of avian reovirus temperature-sensitive mutant recombination groups b, c, and d to genome segments. | we recently generated a new set of avian orthoreovirus (arv) temperature-sensitive (ts) mutants after chemical mutagenesis of wild-type strain arv138 and described mutants in the a recombination group. here, each prototype ts mutant from arv recombination groups b, c, and d was crossed with wild-type arv strain 176 to generate reassortant clones that were used to map the ts lesions in the respective mutants. reassortant clones were identified by comparison of segment mobility to parental markers ... | 2005 | 15955543 |
| extensive syncytium formation mediated by the reovirus fast proteins triggers apoptosis-induced membrane instability. | the fusion-associated small transmembrane (fast) proteins of the fusogenic reoviruses are the only known examples of membrane fusion proteins encoded by non-enveloped viruses. while the involvement of the fast proteins in mediating extensive syncytium formation in virus-infected and -transfected cells is well established, the nature of the fusion reaction and the role of cell-cell fusion in the virus replication cycle remain unclear. to address these issues, we analyzed the syncytial phenotype i ... | 2005 | 15956554 |
| characterization of the sigmab-encoding genes of muscovy duck reovirus: sigmac-sigmab-elisa for antibodies against duck reovirus in ducks. | the sigmab/sigmac-encoding genes of muscovy duck reovirus (drv) s12 strain were cloned, sequenced, and expressed in escherichia coli. the sigmac-encoding gene of drv showed only 21-22% identity to that of avian reovirus (arv) at both nucleotide and amino acid level. the sigmab-encoding gene of drv comprised 1163bp with one open reading frame (orf). the orf comprised 1104bp and encoded 367 amino acids with a predicted molecular mass of 40.44 kda. a zinc-binding motif and a basic amino acid motif ... | 2007 | 17218069 |
| mutations of a residue within the polyproline-rich region of env alter the replication rate and level of cytopathic effects in chimeric avian retroviral vectors. | previous attempts to extend the host range of the avian sarcoma/leukosis virus (aslv)-based rcasbp vectors produced two viral vectors, rcasbp m2c (4070a) and rcasbp m2c (797-8), which replicate using the amphotropic murine leukemia virus 4070a env protein (2). both viruses were adapted to replicate efficiently in the avian cell line df-1, but rcasbp m2c (4070a) caused extensive cytopathic effects (cpe) in df-1 cells whereas rcasbp m2c (797-8) induced low levels of cpe. the two viruses differed o ... | 2005 | 16051819 |
| yeast-derived sigma c protein-induced immunity against avian reovirus. | avian reoviruses (arvs) can result in disease and economic losses in the poultry industry. vaccines against arv may not provide full protection and can cause adverse reactions. the coding sequence of the sigma c protein from strain s1133 of avian reovirus was expressed in schizasaccharomyces pombe. sigma c protein expression was demonstrated by western blotting, and the protein was evaluated for its ability to protect specific-pathogen-free (spf) chickens against challenge with the virulent s113 ... | 2005 | 16094835 |
| retardation of cell growth by avian reovirus p17 through the activation of p53 pathway. | the second open reading frame of avian reovirus s1 gene segment encodes a 17 kda non-structural protein, named p17. the biological role of p17 is fully unknown so far. using trypan blue dye exclusion and mtt assay, we demonstrated that the ectopic expression of p17 results in the reduction of viable cell number and cell proliferation rate of vero, bhk, 293, and hela cells. measurement of ldh activity and dna fragmentation analysis revealed that p17 expression did not cause cell death or apoptosi ... | 2005 | 16143310 |
| the pathogenesis of turkey origin reoviruses in turkeys and chickens. | avian reoviruses that have been shown to be genetically distinct from chicken origin reoviruses were isolated from commercial turkey flocks in the southeastern us and texas that were experiencing enteritis. the pathogenesis of these turkey origin reoviruses (trvs) was evaluated in commercial and specific pathogen free (spf) turkey poults and spf chickens. mortality, clinical disease, gross lesions, microscopic lesions and body weights were observed. trvs replicated poorly and did not cause disea ... | 2005 | 16147564 |
| structure of avian orthoreovirus virion by electron cryomicroscopy and image reconstruction. | among members of the genus orthoreovirus, family reoviridae, a group of non-enveloped viruses with genomes comprising ten segments of double-stranded rna, only the "non-fusogenic" mammalian orthoreoviruses (mrvs) have been studied to date by electron cryomicroscopy and three-dimensional image reconstruction. in addition to mrvs, this genus comprises other species that induce syncytium formation in cultured cells, a property shared with members of the related genus aquareovirus. to augment studie ... | 2005 | 16153672 |
| the goose reovirus genome segment encoding the minor outer capsid protein, sigma1/sigmac, is bicistronic and shares structural similarities with its counterpart in muscovy duck reovirus. | reoviruses have recently been shown to be associated with disease in young geese and to be involved in epizooties of severe outcome in hungary. to assess the genetic variability among these pathogenic goose reoviruses (grvs), we sequenced the s4 genome segment of five grv strains isolated from different diseased flocks. we found that the grv s4 genome segment, consisting of two partially overlapping open reading frames (orfs), shares substantial structural similarity with its counterpart in musc ... | 2005 | 16175334 |
| structure of the carboxy-terminal receptor-binding domain of avian reovirus fibre sigmac. | avian reovirus fibre, a homo-trimer of the sigmac protein, is responsible for primary host cell attachment. the protein expressed in bacteria forms elongated fibres comprised of a carboxy-terminal globular head domain and a slender shaft, and partial proteolysis yielded a carboxy-terminal protease-stable domain that was amenable to crystallisation. here, we show that this fragment retains receptor-binding capability and report its structure, solved using two-wavelength anomalous diffraction and ... | 2005 | 16236316 |
| the survival of avian reoviruses on materials associated with the poultry house environment. | two strains of avian reovirus were tested for their ability to survive on materials common to most poultry houses. the viruses survived longest and for at least 10 days on feathers, wood shavings and chicken feed, and for the shortest periods on wood (2 days), paper and cotton (4 days). there were some differences in survivability between the two strains. in most instances, the presence of faecal material increased the survival time, although in others it had the opposite effect. reovirus surviv ... | 2003 | 17585466 |
| sequences of avian reovirus m1, m2 and m3 genes and predicted structure/function of the encoded mu proteins. | we report the first sequence analysis of the entire complement of m-class genome segments of an avian reovirus (arv). we analyzed the m1, m2 and m3 genome segment sequences, and sequences of the corresponding mua, mub and muns proteins, of two virus strains, arv138 and arv176. the arv m1 genes were 2,283 nucleotides in length and predicted to encode mua proteins of 732 residues. alignment of the homologous mammalian reovirus (mrv) mu2 and arv mua proteins revealed a relatively low overall amino ... | 2006 | 16297481 |
| the sequence and phylogenetic analysis of avian reovirus genome segments m1, m2, and m3 encoding the minor core protein mua, the major outer capsid protein mub, and the nonstructural protein muns. | the sequences and phylogenetic analyses of the m-class genome segments of 12 avian reovirus strains are described. the s1133 m1 genome segment is 2283 base pairs long, encoding a protein mua consisted of 732 amino acids. each m2 or m3 genome segment of 12 avian reovirus strains is 2158 or 1996 base pairs long, respectively, encoding a protein mub or muns consisted of 676 and 635 amino acids, respectively. the s1133 genome segment has the 5' gcuuuu terminal motif, but each m2 and m3 genome segmen ... | 2006 | 16337282 |
| detection and identification of avian, duck, and goose reoviruses by rt-pcr: goose and duck reoviruses are part of the same genogroup in the genus orthoreovirus. | a reverse transcription-polymerase chain reaction (rt-pcr) procedure for the detection of avian, duck, and goose reovirus (arv, drv, and grv) rna from cell culture supernatant and clinical samples was established. based on multiple sequence alignment, a pair of degenerate primers was selected and synthesized. the amplified, cloned, and sequenced 598-base-pair products from the sigmaa-encoding gene fragment from 16 isolates (ranging over 30 years) indicated that the primer regions were well conse ... | 2006 | 16502280 |
| crystallization of the c-terminal globular domain of avian reovirus fibre. | avian reovirus fibre, a homotrimer of the sigmac protein, is responsible for primary host-cell attachment. using the protease trypsin, a c-terminal sigmac fragment containing amino acids 156-326 has been generated which was subsequently purified and crystallized. two different crystal forms were obtained, one grown in the absence of divalent cations and belonging to space group p6(3)22 (unit-cell parameters a = 75.6, c = 243.1 a) and one grown in the presence of either zinc or cadmium sulfate an ... | 2005 | 16511119 |
| novel orthoreovirus from diseased crow, finland. | | 2007 | 18258067 |
| evaluation of the health of free-ranging greater rheas (rhea americana) in argentina. | the health of 22 free-ranging adult rheas (rhea americana) examined and sampled during a translocation/reintroduction project and six juvenile rheas kept in semicaptivity was investigated, and details of their haematology and plasma biochemistry are presented. serological testing for antibodies to infectious agents was negative for infectious laryngotracheitis, avian adenovirus, avian influenza, avian reovirus, infectious bursal disease, infectious bronchitis virus, paramyxovirus types 1, 2, and ... | 2006 | 16517822 |
| characterization of the sigmac-encoding gene from musocvy duck reovirus. | the sigmac-encoding gene of two muscovy duck reovirus (drv) s14 and c4 strains were cloned and completely sequenced. the open reading frame (orf) comprised 810 bp and encoded 269 amino acids with a predicated molecular mass of 29.5 kda. expressed sigmac fusion protein in escherichia coli bl21 strain could be detected by western blotting under duck anti-reovirus polyclonal serum. there are two large gap insertions at the n-terminal part of the drv sigmac when necessary to optimize the alignment o ... | 2006 | 16604448 |
| a monoclonal antibody-based competitive enzyme-linked immunosorbent assay for detecting antibody production against avian reovirus protein sigmaa. | an assay protocol based on a monoclonal antibody-based competitive enzyme-linked immunosorbent assay (mab-based c-elisa) for detection of antibody against avian reovirus protein sigmaa in chicken is described. after the conditions for mab-based c-elisa had been optimized, sera collected from birds that received live and inactivated avian reovirus vaccines in different combinations were tested for antibody response against virus protein sigmaa. the results show a high level of antibody against si ... | 2006 | 16730382 |
| serological survey of racing pigeons for selected pathogens in taiwan. | to investigate the pathogens that racing pigeons in taiwan are exposed to, a total of 3764 pigeons from 90 lofts were analysed by collection of blood samples in the period between october 2000 and september 2001. the haemagglutination inhibition (hi) test was performed to detect antibodies against newcastle disease virus (ndv), type 2 avian paramyxovirus (apmv-2), and egg drop syndrome '76 virus (eds-76v). the agar-gel precipitin (agp) test was used to detect antibodies against fowl adenovirus ( ... | 2006 | 16841756 |
| development and characterization of monoclonal antibodies against avian reovirus sigma c protein and their application in detection of avian reovirus isolates. | avian reovirus (arv) is a non-enveloped virus with a segmented double-stranded rna genome surrounded by a double icosahedral capsid shell. arvs are associated with viral arthritis, immunosuppression, and enteric diseases in poultry. the sigma c protein was involved in induction of apoptosis and neutralization antibody. in the present study, sigma c-his protein was expressed in sf9 insect cells and purified by immobilized metal affinity chromatography. eight monoclonal antibodies (mabs) against s ... | 2006 | 16854646 |
| seroprevalence of avian influenza virus, infectious bronchitis virus, reovirus, avian pneumovirus, infectious laryngotracheitis virus, and avian leukosis virus in nigerian poultry. | eight poultry farms in nigeria, including chickens from nine breeder, 14 broiler, 28 pullet, 11 layer, and three cockerel flocks, were tested for antibody seroprevalence to the following poultry viruses of potential economic importance: infectious bronchitis virus (ibv), avian reovirus, avian pneumovirus (apv), infectious laryngotracheitis virus (iltv), avian influenza virus (aiv), and avian leukosis virus (alv). serum samples were collected between 1999 and 2004 and were tested for antibodies u ... | 2006 | 16863071 |
| health evaluation of free-ranging humboldt penguins (spheniscus humboldti) in peru. | as part of ongoing ecological studies of humboldt penguins (spheniscus humboldti) at punta san juan, ica department, peru, health surveys were conducted in november 1992, 1993, and 1994. in the three surveys, 98 birds in total were handled for examination, and blood was collected for laboratory analysis from 90 of these birds. all birds seemed to be in good condition. body weights of females were significantly lower in 1994 than in the other years. fleas (parapsyllus humboldti) and ticks (ornith ... | 2008 | 18459309 |
| early steps in avian reovirus morphogenesis. | avian reoviruses are important pathogens that may cause considerable economic losses in poultry farming. their genome expresses at least eight structural and four nonstructural proteins, three of them encoded by the s1 gene. these viruses enter cells by receptor-mediated endocytosis, and acidification of virus-containing endosomes is necessary for the virus to uncoat and release transcriptionally active cores into the cytosol. avian reoviruses replicate within cytoplasmic inclusions of globular ... | 2006 | 16909897 |
| development and characterization of a nucleic acid probe for avian reoviruses. | a radiolabelled probe (s4-18), corresponding to 542 base pairs of the s4 genome segment of avian reovirus (arv), was used in dot blot hybridization assays. the lowest limit of purified viral rna detected was similar among three arv strains and was 0.2 ng. the probe also detected nine heterologous strains of arv rna prepared directly from cell cultures, indicating that it had a broad specificity. in addition, the probe detected arv rna in tendon tissues of birds from commercial broiler raising fa ... | 1998 | 18484024 |
| activation of small gtpases rhoa and rac1 is required for avian reovirus p10-induced syncytium formation. | the first orf of the arv s1133 s1 segment encodes the nonstructural protein p10, which is responsible for the induction of cell syncytium formation. however, p10-dependent signaling during syncytium formation is fully unknown. here, we show that dominant negative rhoa, rho inhibitor c3 exoenzyme, rock/rho-kinase inhibitor y-27632 and rac1 inhibitor nsc23766 inhibit p10-mediated cell fusion. p10 over-expression is concomitant with activation and membrane translocation of rhoa and rac1, but not cd ... | 2008 | 18612239 |
| differential expression of u2af35 in the arthritic joint of avian reovirus-infected chicks. | to identify cell types and genes that are differentially expressed during immunopathogenesis of avian reovirus (arv)-induced viral arthritis (va), we inoculated arthrotropic strain s1133 of arv into 1-day-old broilers, and examined tissue histology as well as rna expression at different days post-inoculation (pi). using immunohistochemical staining, we detected many cd68 expressing macrophages in and around the blood vessels of the arthritic joints. by rt-pcr, we found that expression of matrix ... | 2006 | 16916547 |
| mechanisms of reovirus-induced cell death and tissue injury: role of apoptosis and virus-induced perturbation of host-cell signaling and transcription factor activation. | reoviruses have provided insight into the roles played by specific viral genes and the proteins they encode in virus-induced cell death and tissue injury. apoptosis is a major mechanism of cell death induced by reoviruses. reovirus-induced apoptosis involves both death-receptor and mitochondrial cell death pathways. reovirus infection is associated with selective activation of mitogen activated protein kinase (mapk) cascades including jnk/sapk. infection also perturbs transcription factor signal ... | 2005 | 15802955 |
| avian reovirus activates a novel proapoptotic signal by linking src to p53. | we have previously shown that avian reovirus (arv) s1133 and its structural protein sigmac cause apoptosis in cultured vero cells through an unknown intracellular signaling pathway. this work investigates how arv s1133 induces proapoptotic signals. upon arv s1133 infection and subsequent apoptosis, levels of p53 mrna and protein, and p53 serine-46 and serine-392 phosphorylation increased. in addition, p53-driven reporter activity and levels of the p53-induced apoptotic protein bax were increased ... | 2006 | 17051326 |
| central nervous system signs in chickens caused by a new avian reovirus strain: a pathogenesis study. | the present study describes the pathogenesis of infection of chicks with a new avian reovirus strain, belonging to the so-called enteric reovirus strains (ers) that is capable of causing central nervous system signs in spf white leghorns. after intramuscular (im) or oral inoculation birds were either observed for clinical signs or sacrificed for macroscopic, histological and virological examination for 21 days. virus isolation was performed on the brain, leg muscle, hock joint, liver and spleen. ... | 2007 | 17158000 |
| characterization of m-class genome segments of muscovy duck reovirus s14. | this report documents the first sequence analysis of the entire m1, m2, and m3 genome segments of the muscovy duck reovirus (drv) s14. the complete sequence of each of the three m gene segments was determined. the m1 genome segment was 2283 nucleotides in length and was predicted to encode mua protein of 732 residues. the escherichia coli expressed m1 transcripts generated a 108kda protein, as expected for mua. a cleavage product of mua, mua1, could be detected by western blotting with duck anti ... | 2007 | 17218035 |
| sequence and phylogenetic analysis of the s1 genome segment of turkey-origin reoviruses. | based on previous reports characterizing the turkey-origin avian reovirus (trv) sigmab (sigma2) major outer capsid protein gene, the trvs may represent a new group within the fusogenic orthoreoviruses. however, no sequence data from other trv genes or genome segments has been reported. the sigmac protein encoded by the avian reovirus s1 genome segment is the cell attachment protein and a major antigenic determinant for avian reovirus. the chicken reovirus s1 genome segment is well characterized ... | 2007 | 17265142 |
| pathology and virus tissue distribution of turkey origin reoviruses in experimentally infected turkey poults. | the pathogenesis of 4 isolates of turkey-origin reovirus (nc/sep-r44/03, nc/98, tx/98, and nc/85) and 1 chicken-origin reovirus (1733) was examined by infecting specific pathogen free (spf) poults. these turkey-origin reovirus (trv) isolates were collected from turkey flocks experiencing poult enteritis and are genetically distinct from previously reported avian reoviruses. microscopic examination of the tissues collected from the trv-infected poults revealed different degrees of bursal atrophy ... | 2007 | 17317795 |
| genetic variation of the lambdaa and lambdac protein encoding genes of avian reoviruses. | sequence and phylogenetic analysis of lambdaa and lambdac protein encoding genes of 12 avian reoviruses is described. the sequence of lambdaa possesses a variable region (residues 19-51) located within a conserved hydrophilic region (residues 1-110) and a c(2)h(2) zinc-binding motif (residues 182-202). lambdac shows the two conserved k residues at positions 169 and 188 indicative of guanylyltransferase activity, an atp/gtp-binding site motif a (residues 379-386), and a conserved s-adenosyl-l-met ... | 2007 | 17336355 |
| structural and biological characteristics of reoviruses isolated from muscovy ducks (cairina moschata). | two muscovy duck reoviruses, strains y1/79 and 1625/87, were investigated with regard to their genome organization, polypeptide pattern, serotype specificity, and pathogenicity. electrophoretic analysis of the genome revealed the migration pattern of avian reoviruses. in spite of general conformity, great polymorphism was detected in the electrophoretic mobility of individual genome segments of the two strains sharing only three segments of identical size (l1, m2, m3). only one segment (m3) migr ... | 1992 | 18670963 |
| apoptosis induction by avian reovirus through p53 and mitochondria-mediated pathway. | although induction of apoptosis by avian reovirus has been demonstrated in primary chicken embryonic fibroblast and several cell lines, to date, the potential significance of avian reovirus (arv)-induced apoptosis and its pathways in cultured cells are still largely unknown. we now provide the first evidence of upregulation of p53 and bax and specifically for bax translocation from cytosol to mitochondria following infection with a cytoplasmically replicating rna virus. bax translocation to the ... | 2007 | 17379188 |
| avian reovirus-induced apoptosis related to tissue injury. | apoptosis plays an important role in pathogenesis of many viral infections. infection of chicken with avian reovirus s1133 causes tissue injury related to virus-induced apoptosis. to determine whether avian reovirus (arv) induced apoptosis in chicken tissues, six 3-week-old specific pathogen free white leghorn chicks were inoculated with arv s1133. tissues were dual-labelled for the simultaneous detection of viral antigen containing and apoptotic cells. dna laddering was detected in arv-infected ... | 2007 | 17479377 |
| avian reovirus core protein mua expressed in escherichia coli possesses both ntpase and rtpase activities. | analysis of the amino acid sequence of core protein mua of avian reovirus has indicated that it may share similar functions to protein mu2 of mammalian reovirus. since mu2 displayed both nucleotide triphosphatase (ntpase) and rna triphosphatase (rtpase) activities, the purified recombinant mua ( mua) was designed and used to test these activities. mua was thus expressed in bacteria with a 4.5 kda fusion peptide and six his tags at its n terminus. results indicated that mua possessed ntpase activ ... | 2007 | 17485541 |
| crystallization of the avian reovirus double-stranded rna-binding and core protein sigmaa. | the avian reovirus protein sigmaa plays a dual role: it is a structural protein forming part of the transcriptionally active core, but it has also been implicated in the resistance of the virus to interferon by strongly binding double-stranded rna and thus inhibiting the double-stranded rna-dependent protein kinase. the sigmaa protein has been crystallized from solutions containing ammonium sulfate at ph values around 6. crystals belonging to space group p1, with unit-cell parameters a = 103.2, ... | 2007 | 17565188 |
| leaky scanning and scanning-independent ribosome migration on the tricistronic s1 mrna of avian reovirus. | the s1 genome segments of avian and nelson bay reovirus encode tricistronic mrnas containing three sequential partially overlapping open reading frames (orfs). the translation start site of the 3'-proximal orf encoding the sigmac protein lies downstream of two orfs encoding the unrelated p10 and p17 proteins and more than 600 nucleotides distal from the 5'-end of the mrna. it is unclear how translation of this remarkable tricistronic mrna is regulated. we now show that the p10 and p17 orfs are c ... | 2007 | 17604272 |
| [influence of avian reovirus infection on the bursa and immune-reactions in chickens]. | the influences of avian reovirus (arv) infection at 1 day of age on bursa development, antibody responses after vaccinations to avian influenza virus (aiv), newcastle disease virus (ndv) and infectious bursal disease virus (ibdv), and pathogenecity of virulent ibdv (v-ibdv) were studied in chickens of spf-origin. the results indicated that ly strain arv infection in 1-day-old chickens caused atrophy of the bursa and decreased lymphocyte numbers in the bursa, but it gave no significant negative e ... | 2007 | 17672312 |
| suppression of protein expression of three avian reovirus s-class genome segments by rna interference. | rna interference was used to suppress protein expression of three s-class genome segments of avian reovirus (arv). viral progeny titer was successfully down-regulated by rna interference. suppression of s1 genome segment, which has three open reading frames, not only decreased the expression level of the structural protein sigmac but also reduced cell fusion and the level of ser(15)-phosphorylated p53 protein caused by the nonstructural proteins p10 and p17, respectively. suppression of s2 or s4 ... | 2008 | 18191923 |
| sequence and phylogenetic analysis of the s-class genome segments of a duck orthoreovirus. | in spite of common properties duck orthoreoviruses (drvs) are antigenically different from other avian orthoreoviruses (arvs). we analyzed the s-class genome segments of the drv s12 and compared them with s-class genome segments of other orthoreoviruses compared to those of arv s1133. the full-length s-class sigmaa, sigmab, sigmans, and sigmac genes were determined and compared with other arvs to study the degree of genetic divergence and evolution of drvs. the alignment of the drv s12 sigmaa, s ... | 2007 | 18197731 |
| development of a reliable assay protocol for identification of diseases (rapid)-bioactive amplification with probing (bap) for detection of newcastle disease virus. | due to appearance of new genotypes of newcastle disease virus (ndv) with no cross-protection and with vaccine strains, some outbreaks have been reported in taiwan that caused significant damage to the poultry industry. a reliable assay protocol, (rapid)-bioactive amplification with probing (bap), for detection of ndv that uses a nested pcr and magnetic bead-based probe to increase sensitivity and specificity, was developed. primers and probes were designed based on the conserved region of the f ... | 2008 | 18261864 |
| maternal antibodies reduce costs of an immune response during development. | young vertebrates are dependent primarily on innate immunity and maternally derived antibodies for immune defense. this reliance on innate immunity and the associated inflammatory response often leads to reduced growth rates after antigenic challenge. however, if offspring have maternal antibodies that recognize an antigen, these antibodies should block stimulation of the inflammatory response and reduce growth suppression. to determine whether maternal and/or offspring antigen exposure affect a ... | 2008 | 18281327 |
| development of a reliable assay protocol for identification of diseases (rapid)-bioactive amplification with probing for detection of avian reovirus. | avian reovirus (arv) causes several disease syndromes in poultry including arthritis, malabsorption syndrome and chronic respiratory disease that result in major economic losses. early detection is very important for the control of the arv-induced infections. this study was therefore aimed at developing a reliable assay protocol for identification of diseases (rapid)-bioactive amplification with probing (bap) assay for detection of arv. this assay combines nested polymerase chain reaction (pcr) ... | 2008 | 18313146 |
| characterization of interleukin-1beta mrna expression in chicken macrophages in response to avian reovirus. | inhibitors of viral disassembly or rna and protein synthesis, viral disassembly intermediates (infectious subviral particles, isvp), binary ethylenimine-inactivated virions, and viral particles lacking genomic double-stranded (ds) rna (empty particles) were used to assess the expression of interleukin-1beta (il-1beta) mrna in chicken (chil-1beta) macrophages in response to avian reovirus. the results demonstrate that two distinct expression patterns of chil-1beta mrna mediated by different steps ... | 2008 | 18343850 |
| assignment of avian reovirus temperature-sensitive mutant recombination groups e, f, and g to genome segments. | avian reoviruses (arv) are less well understood than their mammalian counterparts. arv are ubiquitous in commercial poultry and frequently isolated from acutely infected chickens. we previously described isolation of arv temperature-sensitive (ts) mutants after nitrosoguanidine mutagenesis of wild-type arv138, their assignment to 7 recombination groups (a-g), and genetic mapping of mutants in groups a-d to specific gene segments. for this study, wild-type serotype arv176 was crossed with ts muta ... | 2008 | 18353422 |
| proteasome inhibition reduces avian reovirus replication and apoptosis induction in cultured cells. | the interplay between avian reovirus (arv) replication and apoptosis and proteasome pathway was studied in cultured cells. it is shown that inhibition of the proteasome did not affect viral entry and host cell translation but had influence on arv replication and arv-induced apoptosis. evidence is provided to demonstrate that ubiquitin-proteasome blocked arv replication at an early step in viral life cycle. however, viral transcription and protein translation were also reduced markedly after addi ... | 2008 | 18455810 |
| serological characteristics of avian reoviruses of australian origin. | the antigenic relationship of plaque purified avian reoviruses isolated from commercial chickens in australia was determined with a serum neutralisation procedure using antisera prepared in rabbits. ten selected isolates were assigned to three groups based upon relatedness values determined by cross-neutralisation studies. considerable cross-reactivity was demonstrated against heterologous types and the three groups were considered to be subtypes rather than distinct serotypes. | 1984 | 18766870 |
| experimental reovirus infection in chickens: observations on early viraemia and virus distribution in bone marrow, liver and enteric tissues. | the nature of viraemia and tissue distribution of reovirus were studied in the early phase after oral infection of 1-day-old specific-pathogen-free (spf) white leghorn chicks with the r2 strain of avian reovirus. a range of tissues collected up to 3 weeks after infection was titrated for their viral content. virus was present in the plasma, erythrocyte and mononuclear fractions of the blood within 30 hours post-inoculation (p.i.) and was widely distributed in tissues, including the bone marrow b ... | 1985 | 18766901 |
| immunogenicity of e. coli-expressed sigma3 protein of avian reovirus in chickens. | an e. coli-expressed fusion protein was used to study the immunogenicity of avian reovirus sigma3 protein in chickens. the protein induced the production of specific antibodies detectable by immunofluorescence, elisa and immunoblot. the antibody titre was low as determined by elisa and was negative by virus neutralization test. however, when tested in passive immunization studies, the chicken antiserum specific to this protein and control antiserum from chickens vaccinated with avian reovirus si ... | 1997 | 18483917 |
| avian reovirus: structure and biology. | avian reoviruses are important pathogens that cause considerable losses to the poultry industry, but they have been poorly characterized at the molecular level in the past, mostly because they have been considered to be very similar to the well-studied mammalian reoviruses. studies performed over the last 20 years have revealed that avian reoviruses have unique properties and activities, different to those displayed by their mammalian counterparts, and of considerable interest to molecular virol ... | 2007 | 17018239 |
| egg transmission of avian reoviruses in chickens: comparison of a trypsin-sensitive and a trypsin-resistant strain. | two groups of commercial light sussex hens with no cultural evidence of reovirus infection and very low titres of neutralising antibodies were mated with cockerels from 17 weeks of age. at 27 weeks of age the birds were separated into three groups, and were inoculated intranasally and intravenously with avian reovirus strain r2 which is resistant to trypsin, with strain tr1 which is sensitive to the enzyme or sham-inoculated. of the eggs laid by the hens infected with strain r2, 13/29 infertile ... | 1996 | 18645873 |
| correlation between neutralizing antibody titre and protection from tenosynovitis in avian reovirus infections. | the relationship between neutralizing antibody titre and protection from tenosynovitis caused by avian reovirus infection was examined using actively or passively immunized chickens. actively immunized groups which developed geometric mean neutralizing antibody titres (gmt) of 1:238 or higher exhibited good protection (more than 71%) against challenge with avian reovirus strain 58-132 via the footpad. on the other hand, 87% of passively immunized chicks, which received chicken serum hyperimmune ... | 1996 | 18645900 |