| control and elimination of porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome virus (prrsv) can have a significant economic impact on swine herds due to reproductive failure, preweaning mortality and reduced performance in growing pigs. control at the farm level is pursued through different management procedures (e.g. pig flow, gilt acclimation, vaccination). prrsv is commonly eliminated from sow herds by a procedure called herd closure whereby the herd is closed to new introductions for a period of time during which resident ... | 2010 | 20837071 |
| molecular epidemiology of prrsv: a phylogenetic perspective. | since its first discovery two decades ago, porcine reproductive and respiratory syndrome virus (prrsv) has been the subject of intensive research due to its huge impact on the worldwide swine industry. thanks to the phylogenetic analyses, much has been learned concerning the genetic diversity and evolution history of the virus. in this review, we focused on the evolutionary and epidemiological aspects of prrsv from a phylogenetic perspective. we first described the diversity and transmission dyn ... | 2010 | 20837072 |
| profiling of cellular proteins in porcine reproductive and respiratory syndrome virus virions by proteomics analysis. | porcine reproductive and respiratory syndrome virus (prrsv) is an enveloped virus, bearing severe economic consequences to the swine industry worldwide. previous studies on enveloped viruses have shown that many incorporated cellular proteins associated with the virion's membranes that might play important roles in viral infectivity. in this study, we sought to proteomically profile the cellular proteins incorporated into or associated with the virions of a highly virulent prrsv strain gdby1, an ... | 2010 | 20849641 |
| nonstructural protein 1α subunit-based inhibition of nf-κb activation and suppression of interferon-β production by porcine reproductive and respiratory syndrome virus. | induction of type i interferon (ifn-α/β) is an early antiviral response of the host, and porcine reproductive and respiratory syndrome virus (prrsv) has been reported to downregulate the ifn response during infection in cells and pigs. we report that the prrsv nonstructural protein 1α (nsp1α) subunit of nsp1 is a nuclear-cytoplasmic protein distributed to the nucleus and contains a strong suppressive activity for ifn-β production that is mediated through the retinoic acid-inducible gene i (rig-i ... | 2010 | 20850164 |
| cd40 ligand expressed in adenovirus can improve the immunogenicity of the gp3 and gp5 of porcine reproductive and respiratory syndrome virus in swine. | porcine reproductive and respiratory syndrome virus (prrsv) has recently caused heavy economic losses in swine industry worldwide. current vaccination strategies only provide a limited protective efficacy, thus immune modulators are being considered to enhance the effectiveness of prrsv vaccines. in this study, the recombinant adenoviruses expressing porcine cd40 ligand (cd40l) and gp3/gp5 of prrsv were constructed and the immune responses were examined in pigs. the results showed that rad-cd40l ... | 2010 | 20851084 |
| taming prrsv: revisiting the control strategies and vaccine design. | porcine reproductive and respiratory syndrome virus (prrsv) continues to be a threat, causing economically significant impacts on the swine industry worldwide. in this article, we share the information related to the thai prrsv and review the available options for prrs control strategies. unfortunately, the traditional control strategies and conventional vaccines fail to provide sustainable disease control, as they suffer from both antigenic heterogeneity and various immune evasion strategies of ... | 2010 | 20851723 |
| characterization of the biochemical properties and identification of amino acids forming the catalytic center of 3c-like proteinase of porcine reproductive and respiratory syndrome virus. | purpose of work: the non-structural protein 4 (nsp4) of porcine reproductive and respiratory syndrome virus (prrsv) functions as a 3c-like proteinase (3clpro) and plays a pivotal role in gene expression and replication. we have examined the biochemical properties of prrsv 3clpro and identified those amino acid residues involved in its catalytic activity as a prelude to developing anti-prrsv strategies. the 3c-like proteinase (3clpro) of porcine reproductive and respiratory syndrome virus (prrsv) ... | 2010 | 20865444 |
| generation of antibody- and b cell-deficient pigs by targeted disruption of the j-region gene segment of the heavy chain locus. | a poly(a)-trap gene targeting strategy was used to disrupt the single functional heavy chain (hc) joining region (j(h)) of swine in primary fibroblasts. genetically modified piglets were then generated via somatic cell nuclear transfer (scnt) and bred to yield litters comprising j(h) wild-type littermate (+/+), j(h) heterozygous knockout (±) and j(h) homozygous knockout (-/-) piglets in the expected mendelian ratio of 1:2:1. there are only two other targeted loci previously published in swine, a ... | 2010 | 20872248 |
| development of a porcine epidemic diarrhea virus m protein-based elisa for virus detection. | a membrane (m), protein-based elisa was developed to detect porcine epidemic diarrhea virus (pedv). the m gene of pedv was expressed in escherichia coli. the purified recombinant m protein was used to immunize rabbits to generate a polyclonal antibody. immunofluorescence analysis indicated that the anti-pedv-m antibody reacted with pedv-infected cells. the antibody was utilized to develop an indirect elisa to detect pedv. other viruses, porcine transmissible gastroenteritis coronavirus, avian in ... | 2010 | 20882317 |
| progress towards a sars vaccine. | | 2010 | 20883159 |
| porcine reproductive and respiratory syndrome virus-induced immunosuppression exacerbates the inflammatory response to porcine respiratory coronavirus in pigs. | we performed a comprehensive analysis of innate and adaptive immune responses in dual-virus infected pigs to understand whether a pre-existing immunomodulatory respiratory viral infection affects the overall immunity to a subsequent porcine respiratory coronavirus (prcv) infection in pigs. pigs were either mock-infected or infected with porcine reproductive and respiratory syndrome virus (prrsv), a virus known to cause immunosuppressive respiratory disease, and then pigs were co-infected with pr ... | 2010 | 20883160 |
| clinical signs and their association with herd demographics and porcine reproductive and respiratory syndrome (prrs) control strategies in prrs pcr-positive swine herds in ontario. | the purposes of this study were to describe the clinical signs observed in prrs positive herds during a porcine reproductive and respiratory syndrome (prrs) outbreak in ontario and to determine associations between these clinical signs and herd demographics and prrs control strategies. all prrs polymerase chain reaction-(pcr)-positive submissions to a diagnostic laboratory between september 1, 2004 and august 31, 2007 were identified (n = 1864). after meeting eligibility requirements and agreein ... | 2010 | 20885840 |
| serodiagnosis of porcine reproductive and respiratory syndrome virus infection with the use of glycoprotein 5 antigens. | glycoprotein 5 (gp5) of porcine reproductive and respiratory syndrome virus (prrsv) has been studied extensively as a target for vaccine development. this study evaluated the serodiagnostic application of prrsv gp5 by enzyme-linked immunosorbent assay (elisa). two immunodominant peptides (vr #1 and vr #2) and two neutralizing ectodomain-containing peptides (ecto #1 and ecto #2), as well as recombinant gp5 (rgp5) as a control, were prepared. serum from unvaccinated pigs was screened for the antib ... | 2010 | 20885848 |
| optofluidic device monitoring and fluid dynamics simulation for the spread of viral pathogens in a livestock environment. | rapid monitoring of the spreads of porcine reproductive and respiratory syndrome virus (prrsv) was attempted using samples collected from nasal swabs of pigs and air samplers within an experimental swine building. an optofluidic device containing liquid-core waveguides was used to detect forward mie light scattering caused by the agglutination of anti-prrsv-conjugated submicron particles, with enhanced sensitivity, signal reproducibility, and reusability (reusable up to 75 assays). these results ... | 2010 | 20886169 |
| porcine reproductive and respiratory syndrome virus infection at the time of porcine circovirus type 2 vaccination has no impact on vaccine efficacy. | several porcine circovirus type 2 (pcv2) vaccines are now commercially available and have been shown to be effective at decreasing the occurrence of porcine circovirus-associated disease (pcvad). many herds are coinfected with pcv2 and porcine reproductive and respiratory syndrome virus (prrsv). some producers and veterinarians are concerned that if pigs are vaccinated for pcv2 at or near the time that they are typically infected with prrsv, the efficacy of the pcv2 vaccine will be compromised. ... | 2010 | 20926694 |
| molecular characterization and antiviral analyses of porcine type iii interferons. | type iii interferons (ifns) are a family of recently identified antiviral cytokines. one to 3 paralogs have been identified in several species; however, little information is available about type iii ifns in pigs. we have identified 2 porcine type iii ifns, sus scrofa ifn-λ1 (ssifn-λ1) and ssifn-λ3, and determined their tissue expression profile and antiviral activities. open reading frames of ssifn-λ1 and ssifn-λ3 are 576 and 588 bp, encoding 191 and 195 amino acid preproteins, respectively. in ... | 2010 | 20929278 |
| aberrant host immune response induced by highly virulent prrsv identified by digital gene expression tag profiling. | there was a large scale outbreak of the highly pathogenic porcine reproductive and respiratory syndrome (prrs) in china and vietnam during 2006 and 2007 that resulted in unusually high morbidity and mortality among pigs of all ages. the mechanisms underlying the molecular pathogenesis of the highly virulent prrs virus (h-prrsv) remains unknown. therefore, the relationship between pulmonary gene expression profiles after h-prrsv infection and infection pathology were analyzed in this study using ... | 2010 | 20929578 |
| porcine reproductive and respiratory syndrome virus: an update on an emerging and re-emerging viral disease of swine. | recognized in the late 1980s in north america and europe the syndrome that caused reproductive and respiratory problems in swine was initially called "mystery swine disease" and is now termed "porcine reproductive and respiratory syndrome (prrs)". in the early 1990 s an arterivirus, referred to as prrs virus (prrsv), was determined to be the etiologic agent of this disease. since then research has progressed substantially. most recently "porcine high fever disease" was reported in china starting ... | 2010 | 20951175 |
| prevalence of porcine reproductive and respiratory syndrome virus (prrsv) antigen-positive uterine tissues in gilts culled due to reproductive disturbance in thailand. | the objective of the present study was to determine the prevalence of porcine reproductive and respiratory syndrome virus (prrsv) antigen-positive uterine tissue in gilts culled due to reproductive disturbance in relation to age at culling, reasons for culling, herds, and prrsv vaccination. uterine tissues of 100 gilts from six swine herds in thailand were collected. the immunohistochemistry was performed to detect the prrsv antigen using a polymer-based non-avidin-biotin technique. prrsv was de ... | 2010 | 20953837 |
| a novel rt-lamp assay for rapid and simple detection of classical swine fever virus. | a simple and rapid assay for the detection of classical swine fever virus (csfv) was established using reverse transcription loop-mediated isothermal amplification (rt-lamp). this study describes the amplification of the genomic rna of csfv under isothermal conditions (63 °c) within one hour, using a set of six primers (two outer primers, two inner primers and two loop primers). this rt-lamp assay showed 100-fold higher sensitivity than the standard rt-pcr method and identified eighteen addition ... | 2010 | 20960285 |
| molecular characterization of porcine circovirus 2 isolated from diseased pigs co-infected with porcine reproductive and respiratory syndrome virus. | in this study, we isolated a porcine circovirus 2 (pcv2) strain from piglets co-infected with porcine reproductive and respiratory syndrome virus (prrsv). the complete genome of this strain was sequenced, phylogenetic and polymorphic analyses were carried out. blast searches revealed the highest sequence identity (99.5% nt and 99.3% aa) to guangxi strain ef675230. the phylogenetic tree showed that clustering of the isolates didn't strongly correlate to geographical distribution. polymorphic anal ... | 2010 | 20979625 |
| activation of nf-κb by nucleocapsid protein of the porcine reproductive and respiratory syndrome virus. | nuclear factor kappa b (nf-κb) is a critical transcription factor in innate and adaptive immune response as well as cell proliferation and survival. previous studies have demonstrated that porcine reproductive and respiratory syndrome virus (prrsv) infection activated nf-κb pathways through iκb degradation in marc-145 cells and alveolar macrophages. to evaluate the mechanisms behind this, we investigated the role of prrsv structural proteins in the regulation of nf-κb. in this study, we screened ... | 2010 | 21063763 |
| molecular cloning, expression and antiviral activity of porcine interleukin-29 (poil-29). | human interleukin-29 (il-29) is a recently discovered cytokine displaying antiviral activity against a broad spectrum of viruses, designated as interferon (ifn)-λ1. we here report the molecular cloning, expression and antiviral activity of porcine il-29 (poil-29). the full-length poil-29 cdna sequence encoded 191 amino acids with a 19 amino acid signal peptide. sequence alignments showed that poil-29 had amino acid sequence similarity to wolf (76%), bear (75%), horse (75%), orangutan (73%), huma ... | 2010 | 21078342 |
| nsp2 gene variation of the north american genotype of the thai prrsv in central thailand. | porcine reproductive and respiratory syndrome virus (prrsv) is a major swine pathogen causing economic losses in the swine industry almost worldwide. prrsv has been divided into 2 genotypes, the european (type 1) and north american (type 2) genotype, respectively and displays a large degree of genetic variability, particularly at the nonstructural protein (nsp) 2 gene. this is the first study determining genetic variation of the nsp2 of thai prrsv isolates. the results showed that 9 out of 10 th ... | 2010 | 21092327 |
| porcine reproductive and respiratory syndrome virus (prrsv) infection activates chemokine rantes in marc-145 cells. | rantes (regulated upon activation, normally t-cell expressed and presumably secreted), a cc chemokine, plays an important role in the inflammatory response associated with viral infections. previous studies have demonstrated that infection with porcine reproductive and respiratory syndrome virus (prrsv) induces rantes transcription in vitro and in vivo. however, the molecular mechanism remains unclear. in this study, real-time rt-pcr and promoter luciferase reporter assays showed that prrsv infe ... | 2010 | 21106247 |
| comparative genomic analysis of five pairs of virulent parental/attenuated vaccine strains of prrsv. | porcine reproductive and respiratory syndrome virus (prrsv), the causative agent of porcine reproductive and respiratory syndrome, is responsible for serious disease in pigs resulting in substantial economic losses in the porcine industry. an attenuated vaccine strain, hun4-f112, was obtained by passaging virulent prrsv strain hun4 on marc-145 cells (for 112 passages), and the full-genomic sequence was determined. to understand the molecular basis of attenuation of prrsv, we compared and analyze ... | 2010 | 21111544 |
| detection of porcine parvovirus using a taqman-based real-time pcr with primers and probe designed for the ns1 gene. | a taqman-based real-time polymerase chain reaction (pcr) assay was devised for the detection of porcine parvovirus (ppv). two primers and a taqman probe for the non-structural protein ns1 gene were designed. the detection limit was 1 x 10² dna copies/μl, and the assay was linear in the range of 1 x 10² to 1 x 10⁹ copies/μl. there was no cross-reaction with porcine circovirus 2 (pcv2), porcine reproductive and respiratory syndrome virus (prrsv), pseudorabies virus (prv), classical swine fever vir ... | 2010 | 21126330 |
| immunopathological characterization of porcine circovirus type 2 infection-associated follicular changes in inguinal lymph nodes using high-throughput tissue microarray. | the immunopathogenesis of porcine circovirus type 2 (pcv2) infection in conventional pigs is complicated by various environmental factors and individual variation and is difficult to be completely reproduced experimentally. in the present field-based study, a tissue microarray (tma) consisting of a series of lymphoid follicles having different pcv2-loads was constructed using formalin-fixed and paraffin-embedded superficial inguinal lymph nodes (lns) from 102 pigs. using the tma, a wide range of ... | 2010 | 21126833 |
| reverse transcription loop-mediated isothermal amplification for rapid detection of transmissible gastroenteritis virus. | transmissible gastroenteritis virus (tgev) is the causative agent of porcine transmissible gastroenteritis, and sensitive detection methods are required for preventing the disease. in this article, reverse transcription-loop-mediated isothermal amplification (rt-lamp) was developed to detect tgev. three pairs of primers targeting the nucleocapsid (n) gene of tgev were synthesized and used in the rt-lamp. the optimization, sensitivity, and specificity of the rt-lamp were evaluated. our results sh ... | 2010 | 21127872 |
| porcine reproductive and respiratory syndrome virus and bacterial endotoxin act in synergy to amplify the inflammatory response of infected macrophages. | in 2006 china experienced outbreaks of a severe form of porcine reproductive and respiratory syndrome (prrs) characterized by high fever, morbidity and mortality in swine irrespective of age. it is thought that secondary bacterial infections may contribute to the generation of this severe form of the disease. to determine the mechanisms by which a highly pathogenic prrsv strain causes high fever we used an in vitro model to investigate the production of the pro-inflammatory cytokines il-1β and t ... | 2010 | 21129861 |
| construction and immunogenicity of dna vaccines encoding fusion protein of murine complement c3d-p28 and gp5 gene of porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome virus (prrsv) has recently caused catastrophic losses in swine industry worldwide. the commercial vaccines only provide a limited protection against prrsv infection. at present, dna vaccine is the focus on the new vaccines. the gene fragment (p28) coding for the molecular adjuvants complement protein c3d (mc3d) from balb/c mouse was cloned and expressed as a fusion protein for its application in the vaccine study of mice. three potential vaccines con ... | 2010 | 21134449 |
| recombination analyses between two strains of porcine reproductive and respiratory syndrome virus in vivo. | porcine reproductive and respiratory syndrome virus (prrsv) is characteristic of genetically extensive variation. in this study, five spf pigs were co-infected with two strains of prrsv (jxwn06-81c and hb-1/3.9c), and 352 viruses were cloned by plaque assay from the sera of the infected pigs on days 3, 5, 7, 10, 14, 21 postinfection (pi), and the recombinant events between the two viruses were systematically investigated by sequencing the orf5, orf3 and nsp2 genes of each cloned virus and using ... | 2010 | 21167230 |
| a virulent strain of porcine reproductive and respiratory syndrome virus does not up-regulate interleukin-10 levels in vitro or in vivo. | porcine reproductive and respiratory syndrome virus (prrsv) causes reproductive failure and respiratory illness in infected pigs. it has been postulated that the ability of prrsv to induce the anti-inflammatory cytokine interleukin-10 (il-10) in macrophages of infected pigs would be important for prrsv immunopathogenesis, although this property would be variable and might be dependent on the strain. several strains were reported to induce il-10 in infected macrophages while others would not. in ... | 2010 | 21168453 |
| evidence for the adaptive evolution of orf5 gene of porcine reproductive and respiratory syndrome virus isolated in china. | porcine reproductive and respiratory syndrome virus (prrsv) orf5 gene encoding an envelope glycoprotein involved in humoral immunity is the most variable protein-coding gene of prrsv. the present study aimed to identify potential selective pressures acting on the orf5 gene of prrsv isolates of north american type prevalent in china. the non-synonymous to synonymous rate ratio ω (dn/ds) was employed as a measure of selective pressure at the codon level. an overall ω of 0.45 indicated negative (pu ... | 2010 | 21175251 |
| north american porcine reproductive and respiratory syndrome viruses inhibit type i interferon production by plasmacytoid dendritic cells. | although enveloped viruses typically trigger the prodigious secretion of alpha interferon (ifn-α) by plasmacytoid dendritic cells (pdc), porcine pdc remain quiescent when exposed to porcine reproductive and respiratory syndrome virus (prrsv). this inactivity is likely due to virus-mediated interference since the typical ifn-α response by either purified or nonsorted porcine pdc to transmissible gastroenteritis virus (tgev) or the toll-like receptor 9 agonist, oligodeoxynucleotide (odn) d19, was ... | 2010 | 21191013 |
| a multiplex rt-pcr for rapid and simultaneous detection of porcine teschovirus, classical swine fever virus, and porcine reproductive and respiratory syndrome virus in clinical specimens. | a multiplex rt-pcr (mrt-pcr) assay was developed and evaluated for its ability to detect multiple viral infections of swine simultaneously. one pair of primers was selected carefully for each of the following three rna viruses: porcine reproductive and respiratory syndrome virus (prrsv), classical swine fever virus (csfv), and porcine teschovirus (ptv). each target produced a specific amplicon with a size of 451bp (prrsv), 343bp (csfv), or 163bp (ptv). the sensitivity of the mrt-pcr using purifi ... | 2010 | 21192983 |
| glycosylation of minor envelope glycoproteins of porcine reproductive and respiratory syndrome virus in infectious virus recovery, receptor interaction, and immune response. | the role of n-glycosylation of the three minor envelope glycoproteins (gp2, gp3, and gp4) of porcine reproductive and respiratory syndrome virus (prrsv) on infectious virus production, interactions with the receptor cd163, and neutralizing antibody production in infected pigs was examined. by mutation of the glycosylation sites in these proteins, the studies show that glycan addition at n184 of gp2, n42, n50 and n131 of gp3 is necessary for infectious virus production. although single-site mutan ... | 2010 | 21195444 |
| mapping quantitative trait loci for innate immune response in the pig. | the aim of the present study was to detect quantitative trait loci (qtl) for the serum levels of cytokines and toll-like receptors as traits related to innate immunity in pig. for this purpose, serum concentration of interleukin 2 (il2), interleukin 10 (il10), interferon-gamma (ifng), toll-like receptor 2 (tlr2) and toll-like receptor 9 (tlr9) were measured in blood samples obtained from f(2) piglets (n = 334) of a duroc × piétrain resource population (dupi) after mycoplasma hypopneumoniae (mh), ... | 2011 | 21199392 |
| [severe clinical problems lasting several weeks on a multiplier pig farm: what if it had been classical swine fever?]. | in the spring of 2009, a veterinarian reported suspected classical swine fever (csf) on a multiplier pig farm in the southern part of the netherlands (close to the belgian border). over a 5-week period there had been a number of sick sows and an excessively high percentage of stillborn and preterm piglets. sick animals were treated with anti-inflammatory drugs and antibiotics, but did not respond as well as anticipated. a visiting specialist team from the food safety authority could not exclude ... | 2010 | 21213448 |
| one dose of a porcine circovirus 2 subunit vaccine induces humoral and cell-mediated immunity and protects against porcine circovirus-associated disease under field conditions. | this study investigated the efficacy of a one-dose porcine circovirus 2 (pcv2) subunit vaccine based on the pcv2 cap protein expressed in a baculovirus system on two different farms at which a history of porcine circovirus-associated disease (pcvd) was present. morbidity, mortality, average daily weight gain, carcass weight, pcv2 load in serum and vaccine immunogenicity were assessed. serology to porcine reproductive and respiratory syndrome virus (prrsv) and mycoplasma hyopneumoniae was perform ... | 2010 | 21216540 |
| emergence of novel european genotype porcine reproductive and respiratory syndrome virus in mainland china. | porcine reproductive and respiratory syndrome (prrs) has a major negative economic impact on the swine industry worldwide. during the investigation of prrs virus (prrsv) in mainland china, european genotype (eu, type 1) prrsv isolates were detected in swine herds both with and without clinical symptoms. two complete genome sequences for chinese type 1 prrsv isolates were identified from viruses isolated from lung tissue and sera. the two viruses, designated bjeu06-1 and nmeu09-1, produced cytopa ... | 2011 | 21216986 |
| chimeric porcine reproductive and respiratory syndrome viruses reveal full function of genotype 1 envelope proteins in the backbone of genotype 2. | porcine reproductive and respiratory syndrome virus (prrsv) is classified into two genotypes, type 1 and type 2, which share only about 60% genetic identity. here, we report viable chimeric viruses in which the envelope protein genes from orf2a to orf5 of vshe (type 1) were swapped into the genetic backbone of vaprrs (type 2). we found that the envelope proteins of genotype 1 were fully functional in genotype 2 prrsv, and the rescued chimeric progeny viruses showed robust genetic stability and s ... | 2011 | 21255814 |
| further assessment of air filtration for preventing prrsv infection in large breeding pig herds. | | 2010 | 21262714 |
| characterization of the porcine p65 subunit of nf-?b and its association with virus antibody levels. | nf-?b p65 subunit plays important roles in controlling both innate and adaptive immunity. here we report the characterization of porcine nf-?b p65 subunit (pp65). pp65 shows high similarity to other mammalian counterparts. pp65 mrna expression was mainly observed in lung, spleen, liver and small intestine. furthermore, overexpression of pp65 activates nf-?b in porcine endothelial cell line piec, porcine alveolar macrophages cell line 3d4/21 and porcine primary fetal fibroblasts. a cooh-terminal ... | 2011 | 21269694 |
| utility of a panviral microarray for detection of swine respiratory viruses in clinical samples. | several factors have recently converged, elevating the need for highly parallel diagnostic platforms that have the ability to detect many known, novel, and emerging pathogenic agents simultaneously. panviral dna microarrays represent the most robust approach for massively parallel viral surveillance and detection. the virochip is a panviral dna microarray that is capable of detecting all known viruses, as well as novel viruses related to known viral families, in a single assay and has been used ... | 2011 | 21270231 |
| a modified live prrsv vaccine and the pathogenic parent strain induce regulatory t cells in pigs naturally infected with mycoplasma hyopneumoniae. | the lack of heterologous protection by porcine reproductive and respiratory syndrome virus (prrsv) vaccines is currently a major problem in the field. heterologous protection by prrs vaccines depends on the ability of the vaccine to induce an interferon gamma (ifn-?) response. one mechanism by which the virus evades the immune system is by activating regulatory t cells (t(regs)), resulting in induction of interleukin 10 rather than ifn-?. our hypothesis that current prrs vaccines do not differ f ... | 2011 | 21272944 |
| detection of prrsv circulation in herds without clinical signs of prrs: comparison of five age groups to assess the preferred age group and sample size. | a cross-sectional study was conducted to find the most effective diagnostic approach to detect circulation of porcine reproductive and respiratory syndrome virus (prrsv). the study was performed in 10 dutch swine herds, with sows and fattening pigs or breeding stock. herds did not experience clinical signs of prrs during the last 6 months before sampling, but a prrsv infection was confirmed at most 2 years before sampling. blood samples were collected from 5 age groups: sows during early and lat ... | 2011 | 21273010 |
| evaluation of the immunogenicity of a transgenic tobacco plant expressing the recombinant fusion protein of gp5 of porcine reproductive and respiratory syndrome virus and b subunit of escherichia coli heat-labile enterotoxin in pigs. | escherichia coli heat-labile enterotoxin b subunit (ltb) can be used as an adjuvant for co-administered antigens. our previous study showed that the expression of neutralizing epitope gp5 of porcine reproductive and respiratory syndrome virus (prrsv) in transgenic tobacco plant (gp5-t) could induce prrsv-specific immune responses in pigs. a transgenic tobacco plant co-expressing ltb and prrsv gp5 as a fusion protein (ltb-gp5-t) was further constructed and its immunogenicity was evaluated. pigs w ... | 2011 | 21277027 |
| molecular characterization of caveolin-1 in pigs infected with haemophilus parasuis. | caveolin-1 (cav1) plays a critical role in the invasion of pathogenic microbes into host cells, yet little is known about porcine cav1. in this study, we provide the molecular characterization of cav1 in pigs following stimulation with lps/polyinosinic-polycytidylic acid as well as during infection with haemophilus parasuis. the porcine cav1 gene is 35 kb long and is located at ssc18q21; two isoforms (cav1-a and cav1-ß) are produced by alternative splicing. three point mutations were identified ... | 2011 | 21282513 |
| development of reverse transcription loop-mediated isothermal amplification for rapid detection of porcine epidemic diarrhea virus. | in this study, a reverse transcription loop-mediated isothermal amplification (rt-lamp) was developed for detection of porcine epidemic diarrhea virus (pedv). six primers were designed to amplify the nucleocapsid (n) gene of pedv. the optimization, sensitivity, and specificity of the rt-lamp were investigated. the results showed that the optimal reaction condition for rt-lamp amplifying pedv n gene was achieved at 63°c for 50 min. the rt-lamp assay was more sensitive than gel-based rt-pcr and en ... | 2011 | 21286798 |
| generation and immunogenicity of transgenic potato expressing the gp5 protein of porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome virus (prrsv) is an important pathogen that has caused huge economic losses in the global swine industry. the advent of molecular farming has provided a cost-effective strategy for the development of transgenic plants as bioreactors to produce recombinant proteins. in this study, transgenic potato expressing gp5 protein of prrsv was produced by agrobacterium-mediated transformation, and confirmed using southern blot and rt-pcr analyses. recombinant g ... | 2011 | 21300109 |
| novel structural protein in porcine reproductive and respiratory syndrome virus encoded by an alternative orf5 present in all arteriviruses. | porcine reproductive and respiratory syndrome virus (prrsv) is an arterivirus that emerged in the late 1980s in both europe and north america as the causative agent of porcine reproductive and respiratory syndrome (prrs), now the most important disease of swine worldwide. despite extensive characterization of prrsv proteins by direct analysis and comparison with other arteriviruses, determinants of virulence, pathogenesis and protective immune recognition remain poorly understood. thus, we hypot ... | 2011 | 21307222 |
| discovery of a small arterivirus gene that overlaps the gp5 coding sequence and is important for virus production. | the arterivirus family (order nidovirales) of single-stranded, positive-sense rna viruses includes porcine respiratory and reproductive syndrome virus and equine arteritis virus (eav). their replicative enzymes are translated from their genomic rna, while their seven structural proteins are encoded by a set of small, partially overlapping genes in the genomic 3'-proximal region. the latter are expressed via synthesis of a set of subgenomic mrnas that, in general, are functionally monocistronic ( ... | 2011 | 21307223 |
| genetic and immunobiological diversities of porcine reproductive and respiratory syndrome genotype i strains. | genetic diversity of porcine reproductive and respiratory syndrome virus (prrsv) has been based on orf5/gp5 and orf7/n protein variations. complete viral genome studies are limited and focused on a single or a few set of strains. moreover, there is a general tendency to extrapolate results obtained from a single isolate to the overall prrsv population. in the present study, six genotype-i isolates of prrsv were sequenced from orf1a to orf7. phylogenetic comparisons and the variability degree of ... | 2011 | 21310555 |
| cytokine profiles and phenotype regulation of antigen presenting cells by genotype-i porcine reproductive and respiratory syndrome virus isolates. | abstract: the present study examined the immunological response of antigen presenting cells (apc) to genotype-i isolates of porcine reproductive and respiratory syndrome virus (prrsv) infection by analysing the cytokine profile induced and evaluating the changes taking place upon infection on immunologically relevant cell markers (mhci, mhcii, cd80/86, cd14, cd16, cd163, cd172a, swc9). several types of apc were infected with 39 prrsv isolates. the results show that different isolates were able t ... | 2011 | 21314968 |
| an evaluation of ultraviolet light (uv254) as a means to inactivate porcine reproductive and respiratory syndrome virus on common farm surfaces and materials. | a study was conducted to assess the effect of uv(254) on the concentration and viability of prrsv on surfaces and materials commonly encountered on swine farms. a standard quantity (5 × 10(6)tcid(50), total dose) of a prrsv modified live vaccine virus was inoculated onto 2 matched sets of surfaces/materials including wood, plastic, latex, rubber, styrofoam, metal, leather, cloth, concrete, cardboard, glass and paper. one set was exposed to uv(254) radiation (treatments) and the other to incandes ... | 2011 | 21330067 |
| indirect elisa with recombinant gp5 for detecting antibodies to porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome is caused by the prrs virus (prrsv), which has six structural proteins (gp2, gp3, gp4, gp5, m and n). gp5 and n protein are important targets for serological detection by enzyme-linked immunosorbent assay (elisa) and other methods. toward this goal, we developed an indirect elisa with recombinant gp5 antigens and this method was validated by comparison to the lsi prrsv-ab elisa kit. the results indicated that the optimal concentration of coated recom ... | 2011 | 21331892 |
| polymorphic genetic characterization of the orf7 gene of porcine reproductive and respiratory syndrome virus (prrsv) in china. | porcine reproductive and respiratory syndrome virus (prrsv) exhibits extensive genetic variation. the outbreak of a highly pathogenic prrs in 2006 led us to investigate the extent of prrsv genetic diversity in china. to this end, we analyzed the nsp2 and orf7 gene sequences of 98 chinese prrsv isolates. | 2011 | 21333014 |
| porcine reproductive and respiratory syndrome virus in ontario, canada 1999 to 2010: genetic diversity and restriction fragment length polymorphisms. | classification of ontario porcine reproductive and respiratory syndrome virus (prrsv) field isolates (n?=?505) from 1999 to 2010, based on a global type 2 prrsv orf5 phylogenetic framework, revealed genetic diversity comparable to prrsv in the usa, with sequences assigned to five of nine lineages (1, 2, 5, 8 and 9). importantly, the tree topology indicated a canadian ancestry for the highly virulent mn184-related strains that first emerged in 2001 in the usa. mapping of the rflp patterns onto th ... | 2011 | 21346028 |
| genetic analysis of orf5 in porcine reproductive and respiratory syndrome virus in japan. | in recent years, no reports regarding genetic information on porcine reproductive and respiratory syndrome virus (prrsv) with a focus on japan have been published. to clarify the effect of time on prrsv genomic evolution, we sequenced the open reading frame 5 (600 or 603 bases) obtained from japanese prrsv isolates for three periods (1992-1993, 2000-2001, and 2007-2008) and compared their phylogenetic relationships. assessment of mean pairwise homology of nucleotide sequences of prrsv isolates i ... | 2011 | 21349102 |
| epidemiological characteristics of pulmonary pneumocystosis and concurrent infections in pigs in jeju island, korea. | epidemiological characteristics of swine pulmonary pneumocystis (p.) carinii and concurrent infections were surveyed on jeju island, korea, within a designated period in 172 pigs submitted from 54 farms to the department of veterinary medicine, jeju national university. the submitted cases were evaluated by histopathology, immunohistochemistry, pcr/rt-pcr, and bacteriology. p. carinii infection was confirmed in 39 (22.7%) of the 172 pigs. histopathologically, the lungs had moderate to severe lym ... | 2011 | 21368558 |
| host inhibits replication of european porcine reproductive and respiratory syndrome virus in macrophages by altering differential regulation of type-i interferon transcriptional response. | porcine reproductive and respiratory syndrome (prrs) is an infectious disease caused by a positive rna strand arterivirus. prrs virus (prrsv) interacts primarily with lung macrophages. little is known how the virus subverts the innate immune response to initiate its replication in alveolar macrophages. large-scale transcriptional responses of macrophages with different levels of susceptibility to prrsv infection were compared over 30 h of infection. this study demonstrates a rapid and intense ho ... | 2011 | 21380581 |
| identification of new defective interfering rna species associated with porcine reproductive and respiratory syndrome virus infection. | in the present study, seven new defective interfering (di) rna species of porcine reproductive and respiratory syndrome virus (prrsv) were identified. rt-pcr, northern blot and sequence analyses indicated that these di rna specie have deletions of 8513-9176 nucleotides located between nsp1/nsp2 and nsp10. compared with the previous di rnas of prrsv reported, they have three distinct characteristics: much smaller deletion sizes; different nucleotide repeats (2-12nt) used in the junction sites and ... | 2011 | 21385595 |
| detection of influenza a virus in porcine oral fluid samples. | porcine oral fluids have been used for the detection of porcine reproductive and respiratory syndrome virus and porcine circovirus-2. the objective of the present study was to determine whether influenza a virus (fluav) is present in porcine oral fluids at detectable levels and to validate a standard fluav molecular diagnostic test for porcine oral fluids. pen-based oral fluid samples were collected on 3, 4, 5, and 6 days postinfection (dpi) from 4 groups of 6 pigs each that were inoculated intr ... | 2011 | 21398442 |
| comparison of rna extraction and real-time reverse transcription polymerase chain reaction methods for the detection of porcine reproductive and respiratory syndrome virus in porcine oral fluid specimens. | the objective of the current study was to evaluate various rna extraction and polymerase chain reaction (pcr) protocols for the detection of porcine reproductive and respiratory syndrome virus (prrsv) in porcine oral fluids. extraction protocols were selected based on ease of use and compatibility with high-throughput, automated systems. the results showed marked differences among extraction protocols, pcr protocols, and combinations thereof in detecting prrsv in the oral fluid matrix. an import ... | 2011 | 21398443 |
| porcine teschovirus polioencephalomyelitis in western canada. | beginning in 2002, a small number of pig farms in western canada began reporting 4-7-week-old pigs with bilateral hind-end paresis or paralysis. low numbers of pigs were affected, some died, most had to be euthanized, and those that survived had reduced weight gains and neurological deficits. necropsies revealed no gross lesions, but microscopic lesions consisted of a nonsuppurative polioencephalomyelitis, most severe in the brain stem and spinal cord. the lesions were most consistent with a vir ... | 2011 | 21398466 |
| the epidemic status and genetic diversity of 14 highly pathogenic porcine reproductive and respiratory syndrome virus (hp-prrsv) isolates from china in 2009. | a high-mortality swine disease, the highly pathogenic porcine reproductive and respiratory syndrome (hp-prrs), reappeared in some regions of china in 2009. to explore the possible mechanisms underlying the emergence of hp-prrsv and more fully understand the extent of the genetic diversity of this virus in china, the complete genome of 14 isolates from 10 provinces in china from 2009 were analyzed. full-length genome sequencing analysis showed that the 14 isolates were closely related to hp-prrsv ... | 2011 | 21411250 |
| immune evasion of porcine reproductive and respiratory syndrome virus through glycan shielding involves both glycoprotein 5 as well as glycoprotein 3. | passive administration of porcine reproductive and respiratory syndrome virus (prrsv) neutralizing antibodies (nabs) can effectively protect pigs against prrsv infection. however, after prrsv infection, pigs typically develop a weak and deferred nab response. one major reason for such a meager nab response is the phenomenon of glycan shielding involving gp5, a major glycoprotein carrying one major neutralizing epitope. we describe here a type ii prrsv field isolate (prrsv-01) that is highly susc ... | 2011 | 21411530 |
| optimal combinations of acute phase proteins for detecting infectious disease in pigs. | abstract: the acute phase protein (app) response is an early systemic sign of disease, detected as substantial changes in app serum concentrations and most disease states involving inflammatory reactions give rise to app responses. to obtain a detailed picture of the general utility of porcine apps to detect any disease with an inflammatory component seven porcine apps were analysed in serum sampled at regular intervals in six different experimental challenge groups of pigs, including three bact ... | 2011 | 21414190 |
| specific, simple and rapid detection of porcine circovirus type 2 using the loop-mediated isothermal amplification method. | porcine circovirus type 2 (pcv2) is the causative agent of postweaning multisystemic wasting syndrome (pmws), and porcine dermatitis and nephropathy syndrome (pdns). it has caused heavy losses in global agriculture in recent decades. rapid detection of pcv2 is very important for the effective prophylaxis and treatment of pmws. | 2011 | 21414233 |
| porcine circovirus-associated disease in weaner pigs in western australia. | to report the occurrence and pathology of porcine circovirus type 2 (pcv2)-associated disease (pcvad) of postweaning pigs in two australian pig herds. | 2011 | 21418168 |
| cross-protective immunity to porcine reproductive and respiratory syndrome virus by intranasal delivery of a live virus vaccine with a potent adjuvant. | porcine reproductive and respiratory syndrome (prrs) is an immunosuppressive chronic respiratory viral disease of pigs that is responsible for major economic losses to the swine industry worldwide. the efficacy of parenteral administration of widely used modified live virus prrs vaccine (prrs-mlv) against genetically divergent prrsv strains remains questionable. therefore, we evaluated an alternate and proven mucosal immunization approach by intranasal delivery of prrs-mlv (strain vr2332) with a ... | 2011 | 21419162 |
| intranasal delivery of whole cell lysate of mycobacterium tuberculosis induces protective immune responses to a modified live porcine reproductive and respiratory syndrome virus vaccine in pigs. | porcine reproductive and respiratory syndrome (prrs) is an economically important disease to pork producers worldwide. commercially, both live and killed prrsv vaccines are available to control prrs, but they are not always successful. based on the results of mucosal immunization studies in other viral models, a good mucosal vaccine may be an effective way to elicit protective immunity to control prrs outbreaks. in the present study, mucosal adjuvanticity of mycobacterium tuberculosis whole cell ... | 2011 | 21419164 |
| the nonstructural protein 1 papain-like cysteine protease was necessary for porcine reproductive and respiratory syndrome virus nonstructural protein 1 to inhibit interferon-+¦ induction. | porcine reproductive and respiratory syndrome virus nonstructural protein 1 (nsp1) could be auto-cleaved into nsp1+¦ and nsp1+¦, both of which had the papain-like cysteine protease activities. previous studies have shown that porcine reproductive and respiratory syndrome virus nsp1 was an interferon (ifn) antagonist. however, the mechanism by which nsp1 inhibited ifn-+¦ production was unclear. here, we used site-directed mutagenesis that inactivated the papain-like cysteine protease activities o ... | 2011 | 21438756 |
| in vitro evaluation of antiviral and virucidal activity of a high molecular weight hyaluronic acid. | hyaluronic acid (ha), a non-sulphated glycosaminoglycan, is present in synovial fluid, vitreous humour serum and many connective tissues. pharmaceutical preparations of ha are used in clinical practice for wound healing, joint pain, kerato-conjunctivitis, asthma, mouth care, oesophageal-reflux, and gastritis. moreover, it is used as a filler to counteract ageing and facial lipoatrophy. our study aims at investigating the in vitro antiviral activity of a high molecular weight ha. | 2011 | 21439070 |
| identification of non-essential regions in nucleocapsid protein of porcine reproductive and respiratory syndrome virus for replication in cell culture. | nucleocapsid (n) protein of porcine reproductive and respiratory syndrome virus (prrsv) plays a central role in virus replication. in this study, serial n- and c-terminal truncations of n protein were performed in the context of type 2 prrsv infectious cdna clone, and our results revealed that a stretch of inter-genotypic variable n terminal residues aa 5-13 ((5)ngkqqkkk(13)k) and the last four inter-genotypic variable aa residues ((120)sps(123)a) at the c terminus of n protein were dispensable ... | 2011 | 21440019 |
| increase of cd163 but not sialoadhesin on cultured peripheral blood monocytes is coordinated with enhanced susceptibility to porcine reproductive and respiratory syndrome virus infection. | porcine reproductive and respiratory syndrome virus (prrsv) has a restricted tropism mainly for porcine alveolar macrophages (pams), but not for peripheral blood monocytes (bmo) in vivo. previous research showed that only a few bmo became susceptible to prrsv infection after 1 day culture. porcine sialoadhesin (posn) and cd163 are identified to be the two main prrsv receptors for binding and internalization. both receptors are not expressed on bmo, or only expressed at low levels, which may expl ... | 2011 | 21440313 |
| effect of compounds on the purification and antibody preparation of the extracellular domain fragment of the receptor cd163. | porcine reproductive and respiratory syndrome virus (prrsv) has been acknowledged as one of the most important agents affecting swine. the scavenger receptor cd163 is one of the important entry mediators for prrsv. | 2011 | 21447173 |
| mannan oligosaccharide improves immune responses and growth efficiency of nursery pigs experimentally infected with porcine reproductive and respiratory syndrome virus. | this study was conducted to determine whether the ingestion of mannan oligosaccharide (mos, bio-mos) alters the immune response of nursery pigs challenged with porcine reproductive and respiratory syndrome virus (prrsv). a total of 64 pigs (3 wk old), free of prrsv, were used in 2 separate but similar experiments conducted sequentially. pigs were blocked by initial bw. sex and ancestry were equalized across treatments. pigs were randomly assigned from within blocks to 1 of 4 treatments in a 2 × ... | 2011 | 21454863 |
| commercial spray-dried porcine plasma does not transmit porcine circovirus type 2 in weaned pigs challenged with porcine reproductive and respiratory syndrome virus. | the objective of this study was to evaluate if spray dried porcine plasma (sdpp) containing porcine circovirus type 2 (pcv2) genome supplemented in feed could transmit pcv2 to pigs challenged with porcine reproductive and respiratory syndrome virus (prrsv). twenty-three prrsv-free pigs, non-viraemic for pcv2, were housed in bio-safety level 3 facilities and assigned to four groups in a 2×2 factorial design consisting of prrsv challenge and a negative control. the diet contained 0 or 8kg sdpp per ... | 2011 | 21458335 |
| identification of immunodominant t-cell epitopes in membrane protein of highly pathogenic porcine reproductive and respiratory syndrome virus. | the development of cell-mediated immunity has been known extremely important in clearing porcine reproductive and respiratory syndrome virus (prrsv) in infected pigs. however, the prrs immunology regarding the interaction of t-cells and prrsv proteins is poorly understood. to identify the t-cell immunodominant epitopes on the membrane (m) protein of prrsv, a series of 31 overlapping pentadecapeptides covering the entire m protein were designed and synthesized. these peptides were screened by eli ... | 2011 | 21458510 |
| [screening of polypeptides binding to porcine reproductive and respiratory syndrome virus by phage display library]. | to find specific polypeptides that bind porcine reproductive and respiratory syndrome virus (prrsv) with high affinity and inhibit replication of prrsv, we screened ligands on intact prrsv virion by phage display library. | 2011 | 21465799 |
| porcine reproductive and respiratory syndrome virus (prrsv)-specific mabs: supporting diagnostics and providing new insights into the antigenic properties of the virus. | the porcine reproductive and respiratory syndrome virus (prrsv) is one of the most important viral pathogens in the swine industry. despite great efforts of pig holders, veterinarians, researchers and vaccine developers, the virus still causes major production losses. it is clear that efficient and correct monitoring and rational development of vaccines are crucial in the combat against this pathogen. prrsv-specific monoclonal antibodies (mabs) are essential tools for both diagnostic and researc ... | 2011 | 21470695 |
| median infectious dose (id(50)) of porcine reproductive and respiratory syndrome virus isolate mn-184 via aerosol exposure. | the median infectious dose (id(50)) of porcine reproductive and respiratory syndrome (prrs) virus isolate mn-184 was determined for aerosol exposure. in 7 replicates, 3-week-old pigs (n=58) respired 10l of airborne prrs virus from a dynamic aerosol toroid (dat) maintained at -4°c. thereafter, pigs were housed in isolation and monitored for evidence of infection. infection occurred at virus concentrations too low to quantify by microinfectivity assays. therefore, exposure dose was determined usin ... | 2011 | 21474258 |
| characterization of a circulating prrsv strain by means of random pcr cloning and full genome sequencing. | abstract: prrs is a pig disease of major economic importance that causes respiratory and reproductive problems in pigs. over the last years it has become clear that prrsv heterogeneity is increasing. consequently, this has a potential impact on diagnosis and strategies to counter this disease. the use of sequence-independent pcr techniques for the detection and characterization of prrsv could be useful to bypass problems associated with the heterogeneity of this virus.a random pcr cloning approa ... | 2011 | 21477345 |
| endoribonuclease activities of porcine reproductive and respiratory syndrome virus nsp11 was essential for nsp11 to inhibit ifn-β induction. | previous studies have shown that prrsv nsp11, which was an endoribonuclease, was an interferon antagonist, however, the mechanism that nsp11 inhibited ifn-β production was unclear. to explore whether the endoribonuclease was required for nsp11 to disrupt the ifn-β production, substitutions of the presumed catalytic histidine and lysine residues of nsp11 were introduced into plasmid pcdna 3.1-flag. the results showed that mutation that inactivated endoribonuclease made nsp11 lose its ability to i ... | 2011 | 21481939 |
| genetic diversity and multiple introductions of porcine reproductive and respiratory syndrome viruses in thailand. | abstract: porcine reproductive and respiratory syndrome virus (prrsv) is prevalent in thailand, causing a huge impact on the country's swine industry. yet the diversity and origin of these thai prrsvs remained vague. in this context, we collected all the thai prrsv sequences described earlier and incorporated them into the global diversity. the results indicated that prrsvs in thailand were originated from multiple introductions involving both type 1 and type 2 prrsvs. many of the introductions ... | 2011 | 21486451 |
| influence of a pig respiratory disease on the pharmacokinetic behaviour of amoxicillin after oral ad libitum administration in medicated feed. | the pharmacokinetic properties of amoxicillin in healthy and respiratory-diseased pigs were studied, after ad libitum administration of medicated feed. in addition, amoxicillin dose linearity and drug penetration into respiratory tract tissues were evaluated in diseased animals. the respiratory disease involves porcine reproductive and respiratory syndrome virus and bacterial agents such as pasteurella multocida, bordetella bronchiseptica and streptococcus suis. typical clinical signs and gross ... | 2011 | 21492192 |
| a 5'-proximal stem-loop structure of 5' untranslated region of porcine reproductive and respiratory syndrome virus genome is key for virus replication. | abstract: | 2011 | 21496223 |
| experimental infection of a newly emerging korean type i porcine reproductive and respiratory syndrome virus isolate in colostrum-deprived pigs. | abstract: | 2011 | 21496335 |
| porcine reproductive and respiratory syndrome virus (prrsv) causes apoptosis during its replication in fetal implantation sites. | reproductive failure due to porcine reproductive and respiratory syndrome virus (prrsv) is characterized by late-term abortions, early farrowing and an increase of dead and mummified fetuses and weak-born piglets. the mechanism of prrsv-induced reproductive failure is poorly understood. human pregnancies, complicated by some pathogens leading to reproductive disorders exhibit increased apoptosis in the fetal membranes. because prrsv-target cells are present in endometrium/fetal placentas from he ... | 2011 | 21511026 |
| vitamin e and selenium levels are within normal range in pigs diagnosed with mulberry heart disease and evidence for viral involvement in the syndrome is lacking. | mulberry heart disease (mhd) in pigs is characterized by lesions of acute haemorrhagic myocarditis and myocardial necrosis. the objectives of this study were to determine the levels of vitamin e and selenium and 13 other trace minerals in heart and liver tissues and to determine the prevalence of certain viral infections in heart tissues from mhd-affected and mhd-unaffected pigs and the vitamin e and selenium concentration in feed samples from selected farms with mhd. based on the pathological e ... | 2011 | 21518323 |
| differentiation of porcine reproductive and respiratory syndrome virus n protein using a virus-based elisa. | the bacterially expressed nucleocapsid (n) protein of porcine respiratory and reproductive syndrome virus (prrsv) was used as immunogen to generate a rabbit-derived polyclonal antibody. the immunoreactivity of the protein to the antibody was confirmed by western blot analysis. using prrsv, transmissible gastroenteritis virus, porcine epidemic diarrhea virus, pseudorabies virus, and avian infectious bronchitis virus as coating antigens, a virus-based elisa was established. the polyclonal antibody ... | 2011 | 21529294 |
| systemic and mucosal immunity induced by attenuated salmonella enterica serovar typhimurium expressing orf7 of porcine reproductive and respiratory syndrome virus. | oral administration of attenuated salmonella vaccine may provide valuable advantages such as low cost, easy preparation, and safety. attenuated salmonella vaccines also serve as carriers of foreign antigens and immunomodulatory cytokines. presently, an attenuated salmonella enterica serovar typhimurium strain was used as a carrier for open reading frame 7 (orf7) protein of porcine reproductive and respiratory syndrome virus (prrsv), a swine pathogen of significant global economic importance. ini ... | 2011 | 21543119 |
| complex assembly, crystallization and preliminary x-ray crystallographic studies of the swine major histocompatibility complex molecule sla-1*1502. | in order to illustrate the structure of the swine mhc class i (sla-i) molecule and to evaluate the cytotoxic t lymphocyte (ctl) response against porcine reproductive and respiratory syndrome virus (prrsv), the ternary complex of the sla-i molecule termed sla-1*1502 with β(2)-microglobulin and the ctl epitope tmppgfely (prrsv-nsp9(ty9)) derived from prrsv nonstructural protein 9 (residues 198-206) was assembled and crystallized. the crystal diffracted x-rays to 2.2 å resolution and belonged to sp ... | 2011 | 21543863 |
| risk assessment of porcine reproductive and respiratory syndrome virus (prrsv) transmission via somatic cell nuclear transfer (scnt) embryo production using oocytes from commercial abattoirs. | somatic cell nuclear transfer (scnt) technology has become a powerful tool for reproductive biology to preserve and propagate valuable genetics for livestock. embryo production through scnt involves enucleation of the oocyte and insertion of a somatic donor cell into the oocyte. these procedures lead to a few small openings on the zona pellucida that may elevate risk of viral infection for the produced scnt embryos. the oocytes used for scnt are mainly obtained from abattoirs where viral contami ... | 2011 | 21550737 |
| inhibition of porcine reproductive and respiratory syndrome virus infection in piglets by a peptide-conjugated morpholino oligomer. | porcine reproductive and respiratory syndrome (prrs) causes substantial economic losses to the swine industry in many countries, and current control strategies are inadequate. previously, we explored the strategy of using peptide-conjugated phosphorodiamidate morpholino oligomers (ppmos) to inhibit prrs virus (prrsv) replication. ppmos are nuclease-resistant and single-stranded dna analogs containing a modified backbone conjugated to a cell-penetrating peptide and can act as antisense agents thr ... | 2011 | 21554902 |
| characterization of antigenic regions in the porcine reproductive and respiratory syndrome virus by the use of peptide-specific serum antibodies. | the porcine reproductive and respiratory syndrome virus (prrsv) is an rna virus that causes reproductive failure in sows and boars, and respiratory disease in pigs of all ages. antibodies against several viral envelope proteins are produced upon infection, and the glycoproteins gp4 and gp5 are known targets for virus neutralization. still, substantial evidence points to the presence of more, yet unidentified neutralizing antibody targets in the prrsv envelope proteins. the current study aimed to ... | 2011 | 21554913 |
| inhibitory effects of indigowoad root polysaccharides on porcine reproductive and respiratory syndrome virus replication in vitro. | indigowoad root polysaccharide (irps) is a natural polysaccharide isolated from the traditional chinese medicinal herb radix isatidis, and has many kinds of biological activities. however, the irps antiviral activity, especially the anti-porcine reproductive and respiratory syndrome virus (prrsv) effect, has not been evaluated. | 2011 | 21555818 |
| antiviral activity of type i and type iii interferons against porcine reproductive and respiratory syndrome virus (prrsv). | the newly identified type iii interferons (ifns), also known as ifn-λ1/il-29, ifn-λ2/il-28a and ifn-λ3/il-28b, like type i ifns, have antiviral activity against a broad spectrum of viruses. we therefore examined whether type iii ifns, as well as type i ifns, has the ability to inhibit porcine reproductive and respiratory syndrome virus (prrsv) replication in marc-145 cells. we found that replication of prrsv in marc-145 cells was significantly reduced following treatment with ifn-λ1, ifn-λ2 and ... | 2011 | 21569798 |