| vp1, the rna-dependent rna polymerase and genome-linked protein of infectious bursal disease virus, interacts with the carboxy-terminal domain of translational eukaryotic initiation factor 4aii. | infectious bursal disease virus (ibdv), a member of the family birnaviridae, is a non-enveloped, double-stranded rna virus. viral protein 1 (vp1), the putative rna-dependent rna polymerase, occurs in virions both as a free polypeptide and as a genome-linked protein, called vpg. to gain more insight in its function, we initiated a yeast two-hybrid screen. with this approach we identified the carboxy-terminal domain of eukaryotic translation initiation factor 4aii (eif4aii) as an interactor for vp ... | 2004 | 15503210 |
| significance of the genetic relationships deduced from partial nucleotide sequencing of infectious bursal disease virus genome segments a or b. | the rapid genomic characterization of infectious bursal disease virus (ibdv) requires determining which partial nucleotide (nt) sequences derived from ibdv segments a or b would produce phylogenetic information as significant as sequencing the whole corresponding segments. long nt coding sequences of 27 ibdv segments a (aa 20-991) and 21 segments b (aa 7-stop codon) were retrieved from databanks and used to compute reference phylogenetic trees using neighbor joining (nj) and parsimony (p): clust ... | 2005 | 15503222 |
| examination of the value of treatment of decompensated viral hepatitis patients by intentionally coinfecting them with an apathogenic ibdv and using the lessons learnt to seriously consider treating patients infected with hiv using the apathogenic hepatitis g virus. | hepatitis virus infection persistent worldwide (approximately 600 m people) results in chronic hepatitis progressing to hepatocellular carcinoma (hcc) in many (approximately 1 m deaths/year). the review examines the usefulness of treating chronic viral hepatitis, including decompensated patients, by intentional coinfection with an attenuated infectious bursal disease virus (ibdv; apathogenic in man, stable at ph 2, orally administered). learning lessons from the ibdv studies, the case is made to ... | 2004 | 15519701 |
| vp1 protein of infectious bursal disease virus modulates the virulence in vivo. | infectious bursal disease viruses (ibdvs), belonging to the birnaviridae family, cause severe immunodeficiency in young chickens by destroying the precursors of antibody-producing b cells in the bursa of fabricius (bf). different pathotypes of ibdvs, including cell culture-adapted viruses, differ markedly in virulence, which is characterized by mortality and bursal damage. to study the molecular determinants of virulence in ibdv, the genomic segments a and b of gls bursa-derived (glsbd) and tiss ... | 2004 | 15527834 |
| genetic characterization of very virulent infectious bursal disease viruses from latin america. | very virulent infectious bursal disease viruses (vvibdvs) were detected in phenol inactivated bursal samples obtained from brazil, the dominican republic, and venezuela. after nucleotide sequence analysis of the hypervariable region of vp2 gene, the vvibdvs from brazil and venezuela exhibited all of the 14 nucleotide changes that are conserved in the european uk-661 and most other vvibdv strains. however, the vvibdv from the dominican republic presented 11 nucleotide changes that are conserved i ... | 2004 | 15529976 |
| immunization of chickens with vp2 protein of infectious bursal disease virus expressed in arabidopsis thaliana. | transgenic plants represent a safe, effective, and inexpensive way to produce vaccines. the immunogenicity of vp2 protein of an infectious bursal disease (ibd) virus variant e isolate expressed in transgenic arabidopsis thaliana was compared with a commercial vaccine in specific-pathogen-free broiler chickens. the vp2 coding sequence was isolated and integrated into a. thaliana genome by agrobacterium tumefaciens-mediated transformation. soluble vp2 expressed in transgenic plants was used to imm ... | 2004 | 15529992 |
| use of multiple antigenic peptides related to antigenic determinants of infectious bursal disease virus (ibdv) for detection of anti-ibdv-specific antibody in elisa--quantitative comparison with native antigen for their use in serodiagnosis. | multiple antigenic peptides (maps) prepared for the predicted antigenic determinants on the vp2 protein of infectious bursal disease virus (ibdv) were used as antigens in enzyme-linked immunosorbent assay (elisa)--an alternative to whole viral antigen to detect anti-ibdv antibodies in the chicken sera. two maps were synthesized, which could specifically detect the anti-ibdv antibodies in serum samples by elisa. the optimum quantity of map1 and map2 required to coat the wells of the elisa plate w ... | 2004 | 15541277 |
| assessment of genetic, antigenic and pathotypic criteria for the characterization of ibdv strains. | the aim of this work was the selection and comparison of representative infectious bursal disease virus (ibdv) strains. nine strains of ibdv, isolated at different times and from different geographic regions of europe and china, were characterized. batches of all strains were prepared following standardized protocols and checked for the absence of contaminating viruses. criteria used for their characterization were: (i) the nucleotide sequence of the vp2 variable region, (ii) binding to a panel ... | 2004 | 15545026 |
| spontaneous colibacillosis in infectious bursal disease-affected broiler flocks. | | 2004 | 15563022 |
| sequence analysis of an indian field isolate of infectious bursal disease virus shows six unique amino acid changes in the vp1 gene. | | 2004 | 15563111 |
| infiltration by cd4+ and cd8+ lymphocytes in bursa of chickens infected with infectious bursal disease virus (ibdv): strain-specific differences. | in order to investigate if there is any definite correlation between the degree of t-cell response in the bursa of fabricius (bf) and the virulence of infectious bursal disease (ibd) virus strains, chickens were infected with strains of different virulence i.e. mild (lukert strain), intermediate (georgia strain) or invasive intermediate (iv-95 strain). at various times post-inoculation, bursal samples were collected to study virus specific histopathological lesions, the distribution of viral ant ... | 2004 | 15573535 |
| evaluation of immunosuppressants and dietary mechanisms in an experimental disease model for necrotic enteritis. | clostridium perfringens (cp) is the etiologic agent of necrotic enteritis (ne). clinical signs of this disease include depression, decreased appetite, diarrhea, and severe necrosis of the intestinal tract. understanding the disease progression of ne has been difficult due to its complexity and the involvement of multiple factors (dietary components, immunosuppression, and mechanical irritation of the gut) that appear to contribute to this syndrome. in the present investigation, day-of-hatch broi ... | 2004 | 15615005 |
| prevention of infectious bursal disease (ibd) by feeding ibd virus-immune bovine colostrum. | addition of 5% freeze-dried ibd virus (ibdv)-immune bovine colostrum to the diet of chickens prevented infection when housed in an ibdv-contaminated environment. four of five chickens receiving 2.5%, and all chickens receiving 0.5% or no ibdv-immune colostrum were infected. no interference with development of an active immunity was found in chickens receiving 5% ibdv-immune colostrum in their diet and vaccinated intramuscularly with modified ibdv. | 1980 | 15615054 |
| secreted expression of the vp2 protein of very virulent infectious bursal disease virus in the methylotrophic yeast pichia pastoris. | the vp2-encoding gene of very virulent infectious bursal disease virus (vvibdv) was amplified using reverse transcription (rt)-polymerase chain reaction (pcr) and inserted into ppiczalphaa vector. recombinant plasmid dna was integrated into the chromosome of the transformed pichia pastoris by electroporation and expressed protein identified by sds-page and western blotting. high-level secreted expression was performed by determining the mut+ phenotype and secreting multi-copy integrants in the r ... | 2005 | 15620405 |
| virus strains from a flock exhibiting unusually high mortality due to infectious bursal disease. | to characterise infectious bursal disease viruses (ibdvs) isolated from commercial broiler flocks exhibiting unusually high mortality due to infectious bursal disease (ibd). | 2004 | 15648939 |
| the enhanced virulence of very virulent infectious bursal disease virus is partly determined by its b-segment. | there is a remarkable difference in virulence of infectious bursal disease virus (ibdv) strains ranging from sub-clinical infections for serotype 2 and cell culture adapted serotype 1 strains, to 100% mortality for very virulent serotype 1 strains in young spf chickens. it is known that cell culture adaptation related attenuation is determined by distinct mutations in the hypervariable region of the vp2 outer capsid protein, encoded on the a-segment. amino acid mutations in the hypervariable vp2 ... | 2004 | 15654506 |
| a very virulent genotype of infectious bursal disease virus predominantly associated with recurrent infectious bursal disease outbreaks in tunisian vaccinated flocks. | outbreaks of infectious bursal disease (ibd) still continue to afflict the tunisian poultry industry even in those flocks where the vaccination program is strictly applied. to characterize the viruses that circumvent protection provided by vaccination, field isolates of infectious bursal disease virus (ibdv) obtained from vaccinated flocks that have repeatedly experienced ibdv outbreak episodes were analyzed from bursal samples by reverse transcription coupled with polymerase chain reaction and ... | 2004 | 15666864 |
| heteroduplex mobility assay for genotyping infectious bursal disease virus. | a heteroduplex mobility assay (hma) was developed to genotype infectious bursal disease virus (ibdv). this method analyzed 390-base pair (bp) polymerase chain reaction (pcr) products, encompassing the hypervariable region of the vp2 gene. ibdv strains from the united states and other countries were analyzed. the hma was able to differentiate standard, antigenic variants and very virulent strains of ibdv. minor differences between different strains from the same subtype were also detected. close ... | 2004 | 15666866 |
| dna immunization against very virulent infectious bursal disease virus with vp2-4-3 gene and chicken il-6 gene. | the present study was to investigate the feasibility and efficiency of the dna vaccine to protect chickens against very virulent infectious bursal disease virus (vvibdv) infection. a plasmid dna carrying vp2-4-3 genes of vvibdv sh95 and a plasmid dna carrying chicken interleukin-6 (chil-6) genes were constructed and designated as palter-max-vp2-4-3 and palter-max-chil-6 respectively. several dna vaccination experiments were performed: 1-week-old chickens were intramuscularly injected with only p ... | 2005 | 15702994 |
| control of infectious bursal disease virus by vaccination. | in summary, the currently used conventional vaccines are used effectively to control the disease. the promise of the new generation of vaccines has not materialized yet. this is partly due to the incomplete understanding of the molecular basis of immunogenicity resulting in an inadequate immune response. it should be emphasized that rna viruses such as ibdv are prone to change through a variety of mechanisms. this requires vigilance in monitoring field viruses and the natural history of the dise ... | 2004 | 15742625 |
| synthesis of reassortant infectious bursal disease virus in chickens injected directly with infectious clones from different virus strains. | the infectious bursal disease virus (ibdv), a member of the birnaviridae family, containing a bisegmented double-stranded rna genome, encodes four structural viral proteins, vp1, vp2, vp3, and vp4, as well as a non-structural protein, vp5. in the present paper, the segment a from two ibdv strains, field isolate zj2000 and attenuated strain hz2, were inserted into one naei site by site-directed silent mutagenesis and subcloned into the eukaryotic expression plasmid pci under the control of the hu ... | 2005 | 15756422 |
| enhanced immunopathology induced by very virulent infectious bursal disease virus. | immunohistochemical and flow cytometric analyses of the bursa, spleen and thymus following infection with the very virulent infectious bursal disease virus (vvibdv) strain uk661 revealed discrete differences from classical virulent infectious bursal disease virus strains. bu-1+, immunoglobulin (ig)m+ and igg+ cells were all depleted from the bursa, spleen and thymus, suggesting loss of both immature and mature b lymphocytes. small numbers of bu-1+ cells repopulated the bursa 14 days post-infecti ... | 2005 | 15763733 |
| early and transient induction of nitric oxide (no) in infectious bursal disease virus infection is t-cell dependent: a study in cyclosporin-a treated chicken-model. | the level of nitric oxide (no) in the supernatants of mitogen (pha) stimulated lymphocyte cultures from infectious bursal disease (ibd) virus infected t-cell suppressed and immune competent chickens was monitored. the immune competent chickens when infected with ibd virus showed 4-6 folds increased levels of no as compared to uninfected chickens. the levels of no in t-cell suppressed chickens were comparable to uninfected control chickens, in spite of markedly increased hemorrhage suggesting tha ... | 2005 | 15782823 |
| infectious bursal disease virus-induced immunosuppression in the chick is associated with the presence of undifferentiated follicles in the recovering bursa. | infectious bursal disease virus (ibdv) causes an acute cytolytic infection in chicken b lymphocytes resulting in destruction of the b-cell population. most severe depletion occurs in the bursa of fabricius, where the immunoglobulin repertoire is developed by gene conversion. chicks surviving ibdv infection are immunosuppressed despite repopulation of the bursa with b cells. here we show that infection of neonatal chicks with a classical virulent ibdv strain (f52/70) causes severe bursal bcell de ... | 2005 | 15802957 |
| pigeon paramyxovirus: association with common avian pathogens in chickens and serologic survey in wild birds. | pigeon paramyxovirus-1 (ppmv-1) was isolated from pigeons from east-central alabama and used in association with chicken anemia virus (cav), infectious bursal disease virus (ibdv), or finch mycoplasma gallisepticum (mg) in specific-pathogen-free chickens to assess dinical disease and pathology. ppmv-1 infection in all groups was conducted at day 10 of age via the ocular route. the low passage ppmv-1 isolate was inoculated into chickens in different groups at 10 days post-cav infection, 6 days po ... | 2005 | 15839419 |
| interference between mild and pathogenic strains of infectious bursal disease virus in chickens. | infectious bursal disease virus is a contagious, immunosuppressive disease of young chickens that is controlled by vaccination. cross-protection occurs between different strains of the virus as a result of shared neutralizing epitopes. however, interactions between two antigenically similar strains (a mild and a pathogenic) coinfecting the same host have not been investigated. groups of specific-pathogen-free chickens were inoculated with a mild strain followed by a pathogenic strain at 0, 16, 2 ... | 2005 | 15839420 |
| infection and activation of bursal macrophages by virulent infectious bursal disease virus. | in this study the effect of infectious bursal disease virus (ibdv) on bursal macrophages during the acute phase of the infection was examined. specific-pathogen-free (spf) chickens were exposed to virulent ibdv and bursal adherent cells were examined by immunohistochemisrty and rt-pcr for virus infection and by real-time quantitative rt-pcr (qrt-pcr) for mrna transcripts of proinflammatory cytokines and inos. viral genome was detected in bursal macrophages at 3, 5 and 7 days post-infection (dpi) ... | 2005 | 15893401 |
| real-time rt-pcr differentiation and quantitation of infectious bursal disease virus strains using dual-labeled fluorescent probes. | a real-time rt-pcr assay was developed utilizing dual-labeled fluorescent probes binding to vp4 sequence that are specific to the classical (cl), variant (v) and very virulent (vv) strains of infectious bursal disease virus (ibdv). the assay was highly sensitive and could detect as little as 3 x 10(2) to 3 x 10(3) copies of viral template. viral genomic copy number could be accurately assayed over a broad range of 7-8 logs of viral genome. the variant sequence-specific probe was found to be high ... | 2005 | 15893570 |
| differences in the immunopathogenesis of infectious bursal disease virus (ibdv) following in ovo and post-hatch vaccination of chickens. | not much is known about ibdv-pathogenesis and immune mechanisms following in ovo vaccination. in this study, we compared the immunopathogenesis of an intermediate ibdv-vaccine in post-hatch- and in ovo-inoculated chickens. in ovo-vaccinated birds recovered significantly faster from lesions of the bursa of fabricius than post-hatch vaccinated (p<0.05). a significant accumulation of intrabursal cd8(+) t cells was observed in post-hatch but not in in ovo-vaccinated chickens (p<0.05). the innate imm ... | 2005 | 15911001 |
| molecular characterization of infectious bursal disease virus isolates from nepal based on hypervariable region of vp2 gene. | two infectious bursal disease virus (ibdv) isolates, np1ssh and np2k were obtained from a severe infectious bursal disease (ibd) outbreak in nepal in 2002. the hypervariable (hv) region of vp2 gene (1326 bp) of the isolates was generated by rt-pcr and sequenced. the obtained nucleotide sequences were compared with those of twenty other ibdv isolates/strains. phylogenetic analysis based on this comparison revealed that np1ssh and np2k clustered with very virulent (vv) ibdv strains of serotype 1. ... | 2005 | 15929400 |
| vaccine and adjuvant activity of recombinant subunit b of e. coli enterotoxin produced in yeast. | escherichia coli heat-labile enterotoxin (lt) and cholera toxin (ct) have been studied intensively as vaccines against diseases caused by those bacteria and as adjuvants for mucosal vaccination. two major problems interfere with the use of these promising adjuvants: their toxicity and the residual bacterial endotoxins mixed with the desired lt. in this study, subunit b of lt was expressed in pichia pastoris yeast cells (yrltb) and the recombinant protein was purified and concentrated by ion-exch ... | 2005 | 15951067 |
| oesophageal tonsil of the chicken. | the oesophageal tonsil of the chicken is a novel member of the mucosal-associated lymphoid tissue (malt), which is located around the entrance of the proventriculus. it consists of 6 to 8 single units, which are surrounded by a thin fibrous capsule. each one is organised around the bottom of the longitudinal folds of the oesophagus, and serves as a 'tonsillar crypt'. stratified squamous epithelium is infiltrated by lymphoid cells, i.e. t cells, plasma cells, macrophages, and dendritic cells, but ... | 2005 | 15959976 |
| [establishment and biological properties of hybridoma cell lines secreting anti-ibdv idiotypic antibodies]. | in recent years, the prevention and cure of infectious bursal disease (ibd) have become more and more difficult due to the emergence of very virulent strains of infectious bursal disease virus (vvibdv) and the variant strains of ibdv. in this research, the hybridoma cell lines which secretes anti-idiotypic antibodies against anti-ibdv igg were established. according to the jerne's theory of immune network, the use of the anti-idiotypic antibodies as a vaccine will be a new method for the prevent ... | 2003 | 15969065 |
| effects of dietary ratio of linoleic to linolenic acid on performance, antibody production, and in vitro lymphocyte proliferation in two strains of leghorn pullet chicks. | the effects of dietary ratio of linoleic acid to linolenic acid on performance, mitogenic lymphocyte proliferation, and antibody production were evaluated in leghorn pullets during a rigorous vaccination program. diets were supplemented with flaxseed and corn oil to achieve 4 dietary ratios of linoleic acid to linolenic acid [17:1 (control), 8:1, 4:1, or 2:1]. each diet was fed to hyline brown or w-36 pullets from 1 d to 16 wk of age. day-old pullets were randomly assigned to 8 replicate cages w ... | 2005 | 15971520 |
| [expression of the infectious bursal disease virus polyprotein in vero cells using attenuated salmonella typhimurium as transgenic carrier]. | to examine if polyprotein gene (vp2/vp4/vp3) of infectious bursal disease virus (ibdv) could be delivered into mammalian cells and expressed using attenuated salmonella typhimurium as vector. the ibdv polyprotein gene was amplified by rt-pcr and inserted in to pci, an eukaryotic expression plasmid. the resulting recombinant pci-vp2/vp4/vp3 was transformed by electroporation into attenuated salmonella typhimurium strain zj111 (dam- and phop-), which was then use to transfect the vero cells. gene ... | 2004 | 15971620 |
| delayed vaccine virus replication in chickens vaccinated subcutaneously with an immune complex infectious bursal disease vaccine: quantification of vaccine virus by real-time polymerase chain reaction. | the distribution of the immune complex vaccine virus for infectious bursal disease (ibd) in tissue was examined and the viral loads of the organs were quantitatively compared. one-day-old specific pathogen free (spf) and maternally immune broiler chickens were injected subcutaneously with the vaccine. lymphoid and non-lymphoid tissues were collected at various time intervals during the experiment to test for infectious bursal disease virus (ibdv)-rna by using reverse transcriptase-polymerase cha ... | 2005 | 15971678 |
| development of recombinant vp2 vaccine for the prevention of infectious bursal disease of chickens. | the objective of the present study was to investigate the feasibility of a subunit vaccine and a live bacteria vaccine to protect chickens against infectious bursal disease virus (ibdv) infection. the gene for vp2 of a new wild-type very virulent ibdv (vvibdv) strain was cloned into an escherichia coli expression system. following expression, the recombinant vp2 and the induced expression bacteria were used to vaccinate chickens against virulent ibdv (vibdv). three weeks after the vaccination, c ... | 2005 | 15979770 |
| recent trends in the molecular diagnosis of infectious bursal disease viruses. | infectious bursal disease virus (ibdv) causes an immunosuppressive disease in young chickens. two serotypes of this double-stranded rna virus exist but only serotype 1 viruses cause disease in chickens. detection and strain identification of ibdv is important because antigenic subtypes found within serotype 1 make it necessary to tailor vaccination programs to the antigenic type found in the bird's environment. because conventional virus isolation and characterization are not practical for routi ... | 2004 | 15984346 |
| differentiation of five strains of infectious bursal disease virus: development of a strain-specific multiplex pcr. | infectious bursal disease virus (ibdv) is a major cause of disease problems in the poultry industry and vaccination has therefore been applied intensively to control the infection. the classical methods of detection and characterization of ibdv are by the use of immunodiffusion test and histopathology. since these methods are laborious and have low specificity alternatives are needed. in the present study, we report the development of a strain-specific multiplex rt-pcr technique, which can detec ... | 2005 | 15994031 |
| structural polymorphism of the major capsid protein of a double-stranded rna virus: an amphipathic alpha helix as a molecular switch. | the infectious bursal disease virus t=13 viral particle is composed of two major proteins, vp2 and vp3. here, we show that the molecular basis of the conformational flexibility of the major capsid protein precursor, pvp2, is an amphipatic alpha helix formed by the sequence gfkdiirair. vp2 containing this alpha helix is able to assemble into the t=13 capsid only when expressed as a chimeric protein with an n-terminal his tag. an amphiphilic alpha helix, which acts as a conformational switch, is t ... | 2005 | 16004873 |
| real-time rt-pcr analysis of two epitope regions encoded by the vp2 gene of infectious bursal disease viruses. | infectious bursal disease virus (ibdv) causes an immunosuppressive disease in chickens and leads to severe economic losses in the poultry industry. vaccination may not be effective if there is exposure of the vaccinated flock to a different antigenic subtype, which reinforces the importance of identification of new ibdv variants. the virus outer capsid is constituted of vp2, in which the major neutralizing epitopes are located. forty-eight bursa samples collected from ibdv infected commercial br ... | 2005 | 16023522 |
| serological investigations of infectious bursal disease virus and reticuloendotheliosis virus infections in new zealand chickens. | | 1982 | 16030899 |
| persistence of infectious bursal disease virus in new zealand commercial egg layer flocks. | | 1995 | 16031803 |
| evaluation of serological, histological and immunocytochemical methods for the detection of infectious bursal disease virus infection in broiler flocks in new zealand. | to study and compare three diagnostic methods for the detection of infectious bursal disease virus (ibdv) infection. | 1999 | 16032098 |
| structure of birnavirus-like particles determined by combined electron cryomicroscopy and x-ray crystallography. | birnaviruses possess a capsid with a single protein layer in contrast to most double-stranded rna viruses infecting multicellular eukaryotes. using freeze-drying and heavy metal shadowing, the capsids of two birnaviruses, infectious bursal disease virus (ibdv) and infectious pancreatic necrosis virus, as well as of an ibdv virus-like particle (vlp) are shown to follow the same t=13 laevo icosahedral geometry. the structure of the vlp was determined at a resolution of approximately 15 a (1.5 nm) ... | 2005 | 16033982 |
| purification of capsid-like particles of infectious bursal disease virus (ibdv) vp2 expressed in e. coli with a metal-ion affinity membrane system. | protein vp2, matured from the polyprotein encoded by the genome of infectious bursal disease virus (ibdv) and the primary host-protective immunogen of this virus, together with its two n-terminal truncated mutants were cloned and expressed in escherichia coli. to obtain pure recombinant proteins for the development of an efficient subunit vaccine against ibdv infection, these three proteins were fused with six additional histidine residues at their c-termini as a his-purification-tag. following ... | 2005 | 16040134 |
| infectious bursal disease virus recovery from vero cells transfected with rna transcripts is enhanced by expression of the structural proteins in trans. | positive sense rna transcripts of infectious bursal disease (ibd) virus genome segments a and b have previously been shown to be infectious. in this study we demonstrate that recovery of ibd virus from the transfection of vero cells with positive sense rna transcripts of genome segments a and b was enhanced by expression of the viral structural proteins vp2 with vp3 or by expression of viral polyprotein vp243 from dna plasmids in trans. expression of individual viral proteins vp2, vp3, or vp4 al ... | 2005 | 16086099 |
| development of a one-step strip test for the diagnosis of chicken infectious bursal disease. | a rapid diagnostic strip for chicken infectious bursal disease (ibd) was developed based on membrane chromatography using high-affinity monoclonal antibodies directed to chicken infectious bursal disease virus (ibdv). the diagnostic strip has high specificity for detection of chicken ibdv antigen and recognizes a variety of the virus isolates, including virulent and attenuated strains, with no cross-reactivity to other viruses, such as newcastle disease virus, marek's disease virus, infectious b ... | 2005 | 16094819 |
| molecular epidemiology of infectious bursal disease viruses: distribution and genetic analysis of newly emerging viruses in the united states. | genetic mutations in the genome of infectious bursal disease virus (ibdv) have resulted in antigenic and pathogenic variants that continue to cause disease in commercially reared chickens. the extent of the genetic diversity among ibdv strains circulating in the united states is unknown. this study was designed to identify newly emerging viruses infecting chickens on poultry farms experiencing immune suppression-related problems. fifty ibdv-positive samples were identified from 273 bursa samples ... | 2005 | 16094826 |
| protective efficacy of intermediate and intermediate plus infectious bursal disease virus (ibdv) vaccines against very virulent ibdv in commercial broilers. | the evolution of very virulent (vv) infectious bursal disease virus (ibdv) has led to significant economic losses in many poultry-producing areas. despite vigorous vaccination strategies, ibdv has been difficult to control. the protective efficacy of ibdv vaccines is traditionally evaluated in specific pathogen-free (spf) chickens. but under field conditions, residual maternal antibody (mab) levels may interfere with vaccine efficacy. in this study, commercial broilers with various levels of mat ... | 2005 | 16094828 |
| molecular studies on suspect very virulent infectious bursal disease virus genomic rna samples. | infectious bursal disease (ibd) associated with high mortality was first observed in europe in the mid-1980s. the viruses identified in those outbreaks were described as being very virulent infectious bursal disease virus (vvibdv) strains. these viruses have spread to nearly every continent but have not yet been identified in north america, australia, and new zealand. there is a real and immediate concern that the very virulent form of ibdv will continue to spread until it is present on every co ... | 2005 | 16094830 |
| molecular epidemiology of chicken anemia virus in nigeria. | between february 2002 and may 2004, chicken anemia virus (cav) was detected by pcr in organ samples from 14 flocks of poultry farms in lagos, ogun and oyo states in southwestern nigeria. the farms reported low (<5%) to high mortalities (up to 100%) with various lesions at necropsy. the complete vp1 gene of 30 of these positive strains was sequenced. strains that diverged by up to 4.4% on a nucleotide level differed only by up to 2.5% at the amino acid level (7 aa) as a result of clustered silent ... | 2006 | 16096706 |
| differential detection of turkey coronavirus, infectious bronchitis virus, and bovine coronavirus by a multiplex polymerase chain reaction. | the objective of the present study was to develop a multiplex polymerase chain reaction (pcr) method for differential detection of turkey coronavirus (tcov), infectious bronchitis coronavirus (ibv), and bovine coronavirus (bcov). primers were designed from conserved or variable regions of nucleocapsid (n) or spike (s) protein gene among tcov, ibv, and bcov and used in the same pcr reaction. reverse transcription followed by the pcr reaction was used to amplify a portion of n or s gene of the cor ... | 2006 | 16137773 |
| development of an experimental model of bacterial chondronecrosis with osteomyelitis in broilers following exposure to staphylococcus aureus by aerosol, and inoculation with chicken anaemia and infectious bursal disease viruses. | a series of experiments was designed in an attempt to reproduce bacterial chondronecrosis with osteomyelitis in broiler chickens using a natural route of infection. birds in isolators were exposed to a suspension of staphylococcus aureus by aerosol or exposed to s. aureus and subsequently inoculated with chicken anaemia virus (cav) alone, or with cav and infectious bursal disease virus (ibdv). subsequently, s. aureus was recovered and bacterial chondronecrosis with osteomyelitis was diagnosed, b ... | 1999 | 16147547 |
| aflatoxicosis, infectious bursal disease and immune response to newcastle disease vaccination in rural chickens. | to investigate the immunosuppressive effects of infectious bursal disease virus (ibdv) and aflatoxin in indigenous chickens of uganda, newcastle disease (nd) seronegative chicks were randomly allocated to two treatment groups. group a chicks were injected intramuscularly at the age of 3 weeks every 2 days up to four times with 0.250 mg aflatoxin b1 per bird, group b was infected occulo-nasally with ibdv 3 days prior to vaccination, while group c was left as a control group. all the chicks from t ... | 2005 | 16147568 |
| evaluation of the suitability of six host genes as internal control in real-time rt-pcr assays in chicken embryo cell cultures infected with infectious bursal disease virus. | infectious bursal disease virus (ibdv) can cause disease in chickens characterized by immunosuppression and high mortality. currently, real-time rt-pcr has been used to quantitate virus-specific rna and to better understand host response to infection. however, normalization of quantitative real-time rt-pcr is needed to a suitable internal control. we thus investigated the expression pattern of six chicken genes, including beta-actin, 28s rrna, 18s rrna, glyceraldehyde-3-phosphate dehydrogenase ( ... | 2005 | 16159698 |
| structural peptides of a nonenveloped virus are involved in assembly and membrane translocation. | the capsid of infectious bursal disease virus (ibdv), a nonenveloped virus of the family birnaviridae, has a t=13l icosahedral shell constituted by a single protein, vp2, and several disordered peptides, all derived from the precursor pvp2. in this study, we show that two of the peptides, pep11 and pep46, control virus assembly and cell entry. deletion of pep11 or even simple substitution of most of its residues blocks the capsid morphogenesis. removal of pep46 also prevents capsid assembly but ... | 2005 | 16160151 |
| l-arginine stimulates immune response in chickens immunized with intermediate plus strain of infectious bursal disease vaccine. | infectious bursal disease continues to pose an important threat to the commercial poultry industry, especially after the emergence of virulent infectious bursal disease virus (ibdv). l-arginine, a ubiquitous, basic amino acid is used as an immunostimulant in variety of human and animal studies with great success in immunosuppressed hosts. in the present study, we evaluated the immunomodulatory effects of l-arginine on humoral and cellular immune response in chickens immunized with live intermedi ... | 2006 | 16168528 |
| infectious bursal disease virus (ibdv) induces apoptosis in chicken b cells. | the ability of infectious bursal disease virus (ibdv) serotypes 1 and 2, and the role of vp4 of both serotypes as well as the capacity of three ibdv intermediate serotype 1-specific vaccine strains to induce apoptosis in a chicken b-lymphocyte cell line, dt40, were investigated using the tunel technique. it was observed that ibdv serotype 1 infected the dt40 cell line and directly induced apoptosis. in contrast, the non-pathogenic serotype 2 neither infected nor induced apoptosis, but was able t ... | 2005 | 16188316 |
| identification of neutralizing epitopes on the vp2 protein of infectious bursal disease virus by phage-displayed heptapeptide library screening and synthetic peptide mapping. | infectious bursal disease virus (ibdv) is the causative agent of infectious bursal disease, which is one of the most important and widespread infectious diseases in commercial chickens. conformational epitopes have been reported in the highly variable region of the vp2 protein of ibdv. in the present study, a random heptapeptide library was screened by using monoclonal antibodies (mabs), ynw17 and ynw29, directed to the vp2 of ibdv and two peptide motifs, d-x-p-r and a-r-g, were identified. the ... | 2005 | 16212534 |
| preparation of chil-2 and ibdv vp2 fusion protein by baculovirus expression system. | this study aims to produce an effective subunit vaccine against infectious bursal disease virus (ibdv). the genes of chicken interleukin-2 (chil-2) and ibdv viral protein 2 (vp2) were amplified and fused by splice overlap extension-polymerase chain reaction (soe-pcr). the fusion gene was digested by ecor i/kpn i and inserted into pbacpak8 vector, resulting in recombinant transfer plasmid pbacpakvp2-il2. the recombinant plasmid was transfected into sf-9 cells accompanied with hybrid nuclear polyh ... | 2005 | 16212892 |
| vaccination against very virulent infectious bursal disease virus using recombinant t4 bacteriophage displaying viral protein vp2. | in order to develop a desirable inexpensive, effective and safe vaccine against the very virulent infectious bursal disease virus (vvibdv), we tried to take advantage of the emerging t4 bacteriophage surface protein display system. the major immunogen protein vp2 from the vvibdv strain hk46 was fused to the nonessential t4 phage surface capsid protein, a small outer capsid (soc) protein, resulting in the 49 kda soc-vp2 fusion protein, which was verified by sodium dodecylsulfate polyacrylamide ge ... | 2005 | 16215632 |
| temporal and spatial analysis of the 1999 outbreak of acute clinical infectious bursal disease in broiler flocks in denmark. | the objective of this study was to describe the spatial and temporal dynamics of the 1999 outbreak of acute clinical infectious bursal disease (ibd) in broiler chicken farms in denmark. the analysis was performed using data from all broiler farms located in the jutland peninsula and the island of funen (168 municipalities). the moran's index i, k-functions and scan statistics were used to describe the dynamics of the epidemic. in addition, spatially correlated survival analyses were performed an ... | 2005 | 16227094 |
| viral genotyping of infectious bursal disease viruses isolated from the 2002 acute outbreak in spain and comparison with previous isolates. | an infectious bursal disease (ibd) outbreak occurred in the east region of spain in the spring of 2002 and rapidly spread thorough the whole country, although proper vaccination programs were applied. in this report, 33 infectious bursal disease viruses (ibdvs) isolated from this outbreak were characterized by nucleotide sequencing of the vp2 gene hypervariable region and were compared with reference ibd strains and the 1990s spanish ibdvs in order to determine possible emergence of ibdv isolate ... | 2005 | 16252484 |
| reproduction of proventriculitis in commercial and specific-pathogen-free broiler chickens. | proventriculitis was studied by experimentally reproducing the disease in broiler chickens. one-day-old infectious bursal disease virus (ibdv) and infectious bronchitis virus (ibv) antibody positive commercial broilers and 1-day-old antibody negative specific-pathogen-free (spf) broilers were orally gavaged with proventricular homogenates produced from the proventriculi of broilers with proventriculitis. at 7 and 14 days, both commercial and spf broilers had enlargement of the proventriculus wit ... | 2005 | 16252487 |
| intracellular interference of infectious bursal disease virus. | a search for dominant-negative mutant polypeptides hampering infectious bursal disease virus (ibdv) replication has been undertaken. we have found that expression of a mutant version of the vp3 structural polypeptide known as vp3/m3, partially lacking the domain responsible for the interaction with the virus-encoded rna polymerase, efficiently interferes with the ibdv replication cycle. transformed cells stably expressing vp3/m3 show a significant reduction (up to 96%) in their ability to suppor ... | 2005 | 16254378 |
| infectious bursal disease in ghana. | | 1976 | 16300347 |
| 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 |
| genetic variations in maternal transfer and immune responsiveness to infectious bursal disease virus. | the immune responsiveness to infectious bursal disease virus (ibdv) in four native and crossbred chicken lines was compared. elisa ibdv antibody titers in hen serum samples, yolk from matched eggs and sera from matched 1-day-old chicks from each chicken line with an identical vaccination program were measured, and plotted. there was considerable variation between lines in the measured ibdv specific antibodies, in vaccinated parent hens and in the amounts of inherited maternally derived antibodie ... | 2006 | 16337348 |
| [cloning, expression and preparation of polyclonal antibody for ibdv non-structure protein gene]. | infectious bursal disease virus (ibdv) vp5 gene was amplified and cloned into an n-terminal gst-tag fusion expression vector, pgex-4t-2, which was controlled by t7 promoter. the sequencing result showed that the vp5 gene was composed of 438 base pairs, and coded 145 amino acids. high vp5 product was expressed in e. coli bl21 induced by iptg, and the gst-vp5 fusion protein existed in inclusion. high titer anti-vp5 serum was also prepared in new zealand rabbit immunized with purified fusion protei ... | 2005 | 16342772 |
| very virulent infectious bursal disease virus: reduced pathogenicity in a rare natural segment-b-reassorted isolate. | the purpose of this study was to compare the molecular epidemiology of infectious bursal disease virus (ibdv) segments a and b of 50 natural or vaccine ibdv strains that were isolated or produced between 1972 and 2002 in 17 countries from four continents, with phenotypes ranging from attenuated to very virulent (vv). these strains were subjected to sequence and phylogenetic analysis based on partial sequences of genome segments a and b. although there is co-evolution of the two genome segments ( ... | 2006 | 16361433 |
| two outbreaks of very virulent infectious bursal disease virus in pakistan. | | 2005 | 16361477 |
| haematological and histological findings in leghorn chickens infected with infectious bursal disease virus strain 73688. | in the present study, specific-pathogen-free, 2-week-old leghorn chickens were experimentally infected with strain 73688 of infectious bursal disease virus (ibdv) in order to evaluate haematological and histological changes that might suggest a pathomechanism for haemorrhages in this disease. at 96 hours post infection (hpi) a significant increase in prothrombin time was detected in the absence of visible lesions in myeloid bone marrow tissue and of significant thrombocytopenia. the aforemention ... | 2005 | 16363151 |
| infectious bursal disease virus infection induces macrophage activation via p38 mapk and nf-kappab pathways. | in the present study, we show that infection with infectious bursal disease virus (ibdv) causes activation of macrophages, the key cells involved in inflammatory and immune-regulatory functions. exposure of cultured spleen macrophages (sm) from spf chickens to ibdv resulted in the production of nitric oxide (no). in addition, there was upregulation of mrna expression of inducible nitric oxide synthase (inos), il-8 and cyclooxygenase-2 (cox-2). the signal transduction pathways involved in macroph ... | 2006 | 16388870 |
| detection of vvibdv in vaccinated spf chickens. | the purpose of our experiment was to investigate, if apparently healthy, vaccinated chickens may be involved in maintaining and spreading infectious bursal disease virus (ibdv) in poultry environments. we aimed at simultaneous detection and identification of very virulent field strain ibdv (vvibdv) as well as vaccine strain ibdv in experimentally infected chickens. two groups of specific pathogen free (spf) chickens were vaccinated using the intermediate infectious bursal disease (ibd) vaccine d ... | 2005 | 16398333 |
| genotyping of infectious bursal disease virus strains by restriction fragment length polymorphism analysis of the vp1, vp2, and vp3 genes. | summary. this study aimed to genotype infectious bursal disease virus (ibdv) isolates from the minas gerais state poultry industry. rna was extracted from bursae obtained from field cases without passage or commercial vaccines. genetic subtyping of ibdv isolates and vaccine strains was carried out by the reverse transcriptase-polymerase chain reaction (rt-pcr) and restriction fragment length polymorphism (rflp) analysis. a 588-bp fragment in the vp1 gene, an 847-bp fragment in the vp2 gene, and ... | 2005 | 16404990 |
| detection of infectious bursal disease virus in various lymphoid tissues of experimentally infected specific pathogen free chickens by different reverse transcription polymerase chain reaction assays. | infectious bursal disease (ibd) is a worldwide distributed immunosuppressive viral disease in young chickens, controlled by vaccination. emergence of several strains of ibd virus (ibdv) has created a demand for strain-specific diagnostic tools. in the present experiment, five different reverse transcription polymerase chain reaction (rt-pcr) assays, including two recently developed strain-specific assays, were employed for detection of ribonucleic acid (rna) from three different ibdv strains in ... | 2005 | 16404995 |
| passive immunization using purified igys against infectious bursal disease of chickens in pakistan. | infectious bursal disease (ibd) is an acute and highly contagious disease of young chickens caused by birnavirus. mortality of infected birds can be best prevented if injected with antibodies. the present study was an attempt to raise specific hyper-immune polyclonal antibodies against ibd virus in pakistan. commercial layers divided into four groups were injected with ibd vaccine subcutaneously according to four different treatment regimens. eggs were collected daily and antibodies were purifie ... | 2006 | 16434848 |
| preparation and evaluation of vero-cell infectious bursal disease vaccine in pakistan. | the present work was carried out to develop an effective vaccine to control infectious bursal disease (ibd). the very virulent infectious bursal disease virus (vvibdv) was adapted to grow in vero-cell line after three serial passages. the virus was then attenuated by further serial passages and pathogenicity of different passages was determined in broiler chicks free from antibodies against ibdv. the ninth passage virus was completely attenuated, as it was non-pathogenic to chicks. the birds ino ... | 2006 | 16490290 |
| chicken recombinant antibodies specific for very virulent infectious bursal disease virus. | a phage-displayed single chain variable fragment (scfv) antibody library was constructed from the immune spleen cells of chickens immunized with very virulent infectious bursal disease virus (vvibdv) strain cs89. a library consisting of around 9.2 x 10(7) clones was subjected to 3 rounds of panning against captured cs89 virus. analysis of individual clones by nucleotide sequencing revealed at least 22 unique scfv antibodies binding to vvibdv in elisa. testing of the scfv antibody panel in elisa ... | 2006 | 16514499 |
| inactivation of infectious bursal disease virus by binary ethylenimine and formalin. | in this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (ibdv) by binary ethylenimine (bei) in comparison with formalin, ibdv was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. viral suspensions were subjected to inactivation with bei and formalin for pre-set time intervals. bei was employed at concentrations of 0.001 and 0.002 mol/l while formalin was used at 0.1% and 0.2%. sampling was done a ... | 2006 | 16532536 |
| an elisa for detection of infectious bursal disease virus and differentiation of very virulent strains based on single chain recombinant chicken antibodies. | two chicken single-chain variable antibody fragments (scfv) designated scfv154 and scfv88, previously shown to react with either all or very virulent (vv) infectious bursal disease virus (ibdv) strains, respectively, were evaluated for use in an enzyme-linked immunosorbent assay (elisa) for differentiation of vvibdv. specificity and sensitivity of the vvibdv elisa was assessed when scfv154 and scfv88 were expressed as soluble antibodies (sab), phage antibodies (pab) or hyper-phage antibodies (hp ... | 2005 | 16537158 |
| evaluation of the enzyme-linked immunosorbent assay for the detection of antibodies against infectious bursal disease virus (ibdv) and the estimation of the optimal age for ibdv vaccination in broilers. | in order to evaluate the usefulness of the enzyme-linked immunosorbent assay (elisa) in determining the optimal age for infectious bursal disease virus (ibdv) vaccination in broilers under field circumstances, the percentage of birds susceptible to vaccine at vaccination age was estimated in 12 flocks on the basis of elisa titres in newborn chicks. the effective percentage of susceptible birds at the day of vaccination was checked by comparing virus neutralization (vn) titres measured in sera ta ... | 2005 | 16537166 |
| nonstructural protein of infectious bursal disease virus inhibits apoptosis at the early stage of virus infection. | infectious bursal disease virus (ibdv), the causative agent of a highly contagious disease in chickens, carries a small nonstructural protein (ns). this protein has been implicated to play a role in the induction of apoptosis. in this study, we investigate the kinetics of viral replication during a single round of viral replication and examine the mechanism of ibdv-induced apoptosis. our results show that it is caspase dependent and activates caspases 3 and 9. nuclear factor kappa b (nf-kappab) ... | 2006 | 16537604 |
| infectious bursal disease virus: strains that differ in virulence differentially modulate the innate immune response to infection in the chicken bursa. | little is understood about the immune responses involved in the pathogenesis of infectious bursal disease virus (ibdv). strains of ibdv differ in their virulence: f52/70 is a classical virulent strain (vibdv), whereas uk661 is a very virulent strain (vvibdv) that causes greater pathology and earlier mortality. the exact causes of clinical disease and death are still unclear. pro-inflammatory cytokines such as interleukin (il)-1beta and il-6, produced by activated macrophages, could play a role, ... | 2006 | 16553553 |
| diversified bursal medullary b cells survive and expand independently after depletion following neonatal infectious bursal disease virus infection. | the primary immunoglobulin repertoire of chickens is generated not by gene rearrangement but by a subsequent process of gene conversion in proliferating immature b cells within the follicles of a specialized gut-associated lymphoid organ, the bursa of fabricius. neonatal infection with infectious bursal disease virus can eliminate almost the entire bursal b-cell compartment. thereafter, two types of follicle reappear. larger follicles, with rapidly proliferating b cells and normal structure, are ... | 2006 | 16556270 |
| crystal structure of a novel viral protease with a serine/lysine catalytic dyad mechanism. | the blotched snakehead virus (bsnv), an aquatic birnavirus, encodes a polyprotein (nh2-pvp2-x-vp4-vp3-cooh) that is processed through the proteolytic activity of its own protease (vp4) to liberate itself and the viral proteins pvp2, x and vp3. the protein pvp2 is further processed by vp4 to give rise to the capsid protein vp2 and four structural peptides. we report here the crystal structure of a vp4 protease from bsnv, which displays a catalytic serine/lysine dyad in its active site. this is th ... | 2006 | 16584747 |
| molecular characterization of recent infectious bursal disease virus isolates from malaysia. | three isolates of infectious bursal disease virus (ibdv), designated upm04178, upm04190 and upm04238, were obtained from severe outbreaks of infectious bursal disease (ibd) in malaysia in 2004. the hypervariable region (hpvr) of vp2 gene of these isolates was sequenced. the obtained sequences were compared with those of other isolates. the highest similarity (98%) concerning both nucleotide and amino acid sequences was found to very virulent ibdv (vvibdv) strains. phylogenetic analysis revealed ... | 2006 | 16599185 |
| protection capability of recombinant plasmid dna vaccine containing vp2 gene of very virulent infectious bursal disease virus in chickens adjuvanted with cpg oligodeoxynucleotide. | in the present study the efficacy of recombinant plasmids dna vaccine encoding vp2 gene of very virulent strain of infectious bursal disease virus (vvibdv) isolated from pakistan was investigated with or without coadministration of cytocine-phosphate-guanine oligodeoxynucleotide (cpg odn) to protect the chickens against the disease. vp2 gene of vvibdv was successfully amplified by reverse transcription-polymerase chain reaction (rt-pcr) and was cloned into eukaryotic expression plasmid vector, w ... | 2006 | 16600440 |
| [inhibitory effect of new antimicrobial substance by bacillus subtilis fmbj on newcastle disease virus and infectious bursal disease virus in vitro]. | the resistance effect on newcastle disease virus (ndv) and infectious bursal disease virus(ibdv) in vitro of a new antimicrobial substance (as), which produced by a bacillus subtilis strain named b. subtilis fmbj. results showed that the td50 and td0 value of this as on chicken embryo fibroblasts cell (cef) were 128.95mg/l and 25.79mg/l, respectively. this as could strongly inhibit the cytopathic effects of cell induced by ndv as well as ibdv, and increase the survival rate of cell remarkably. t ... | 2006 | 16607965 |
| detection of antibodies against serotypes 1 and 2 infectious bursal disease virus by commercial elisa kits. | two distinct serotypes of infectious bursal disease virus (ibdv) are recognized in chicken and turkey flocks in the united states. serologic testing of chicken flocks for serotype 1 viruses is routinely performed to monitor disease status and vaccination. earlier studies indicated that enzyme-linked immunosorbent assay (elisa) test detects antibodies to both serotypes of the virus, while the virus neutralization (vn) test is serotype specific. it is useful to evaluate currently available commerc ... | 2006 | 16617991 |
| in ovo dna immunisation followed by a recombinant fowlpox boost is fully protective to challenge with virulent ibdv. | the aim of this study was to investigate the potential use of dna vaccination delivered in ovo for protecting against challenge with infectious bursal disease virus (ibdv). using a plasmid expressing the beta-galactosidase gene, dna was successfully delivered to the embryo after in ovo injection and localises to the proventriculus and thymus. the coding sequence for the immunogenic ibdv protein, vp2, was cloned into pci-neo, creating pci-vp2. complete protection against ibdv was obtained by prim ... | 2006 | 16621184 |
| application of on-line our measurements to detect actions points to improve baculovirus-insect cell cultures in bioreactors. | the continuous monitoring of a process based on the culture of sf9 insect cells and infection by a baculovirus as a vector to obtain recombinant vp2 protein is studied. on-line our determination is based on the direct oxygen measurement in the cell culture vessel and the application of the dynamic method. this approximation allows a proper description of cell growth, with precise identification of the balanced cell growth end and the most important action times in the process, as virus infection ... | 2006 | 16647779 |
| crystal structure of infectious bursal disease virus vp2 subviral particle at 2.6a resolution: implications in virion assembly and immunogenicity. | the structural protein vp2 of infectious bursal disease virus (ibdv) spontaneously forms a dodecahedral t=1 subviral particle (svp), and is a primary immunogen of the virus. in this study, the structure of ibdv svp was determined in a cubic crystal and refined to 2.6a resolution. it contains 20 independent vp2 subunits in a crystallographic asymmetric unit. each subunit is folded mainly into a shell domain and a protrusion domain, both with the swiss-roll topology, plus a small helical base doma ... | 2006 | 16677827 |
| relative quantification and detection of different types of infectious bursal disease virus in bursa of fabricius and cloacal swabs using real time rt-pcr sybr green technology. | in present study, different types of infectious bursal disease virus (ibdv), virulent strain dk01, classic strain f52/70 and vaccine strain d78 were quantified and detected in infected bursa of fabricius (bf) and cloacal swabs using quantitative real time rt-pcr with sybr green dye. for selection of a suitable internal control gene, real time pcr parameters were evaluated for three candidate genes, glyceraldehyde-3-phosphate dehydrogenase (gapdh), 28s rrna and beta-actin to ibdvs. based on this ... | 2007 | 16678230 |
| b subunit of e. coli enterotoxin as adjuvant and carrier in oral and skin vaccination. | mucosal sites are one of the main natural ports of entry into the body. stimulation of a local response by antibodies as the systemic protection may enhance the efficacy of non-living vaccines, and allow for vaccination by subunit vaccines without the need for injection. mucosal or skin vaccination necessitates a suitable adjuvant and carrier. escherichia coli heat-labile enterotoxin (lt) and its b subunit (ltb) have been found to be effective adjuvants. the aim of this study was to efficiently ... | 2006 | 16701905 |
| purification of vp3 protein of infectious bursal disease virus using nickel ion-immobilized regenerated cellulose-based membranes. | in this study, hexa-histidine tagged vp3 protein of infectious bursal disease virus (ibdv) was purified using immobilized metal ion affinity technique from the fermentation of escherichia coli bl21 (de3) containing a recombinant plasmid with a vp3 gene. the purification efficiencies of vp3 protein (tvp3 and deltatvp3) using ni(2+)-nta commercial agarose gels and ni(2+)-ida regenerated cellulose-based membranes at 4 degrees c were compared. a good washing condition for removing most impurity prot ... | 2006 | 16716768 |
| l-arginine stimulates intestinal intraepithelial lymphocyte functions and immune response in chickens orally immunized with live intermediate plus strain of infectious bursal disease vaccine. | infectious bursal disease (ibd) continues to pose potential threat to poultry industry all over the world. the disease can spell disaster not only through its infection but also by break of immunity in chickens vaccinated for other diseases. l-arginine, a ubiquitous, semi-essential amino acid has emerged as an imunostimulant from variety of human and animal studies. in the present study, we demonstrate the stimulatory effects of l-arginine on intestinal intraepithelial lymphocyte (iiels) functio ... | 2006 | 16723175 |
| processing of infectious bursal disease virus (ibdv) polyprotein and self-assembly of ibdv-like particles in hi-5 cells. | the capsid of infectious bursal disease virus (ibdv), with a size of 60-65 nm, is formed by an initial processing of polyprotein (pvp2-vp4-vp3) by vp4, subsequent assemblage of pvp2 and vp3, and the maturation of vp2. in sf9 cells, the processing of polyprotein expressed was restrained in the stage of vp2 maturation, leading to a limited production of capsid, i.e., ibdv-like particles (vlps). in the present study, another insect cell line, high-five (hi-5) cells, was demonstrated to efficiently ... | 2006 | 16739960 |
| phylogenetic diversity of avian nephritis virus in hungarian chicken flocks. | avian nephritis virus (anv) infection was detected in 4-day-old to 22-day-old chickens collected on hungarian farms between 2002 and 2005. the animals suffered from diarrhoea, growth retardation, runting-stunting syndrome, and 2 to 6% mortality was reported. tubulonephrosis, interstitial nephritis and uricosis (gout) was diagnosed. the presence of anv rna was detected in chicken carcasses using reverse transcriptase-polymerase chain reaction. the virus was demonstrated in 69% of the investigated ... | 2006 | 16753614 |