Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022104 (irritable bowel syndrome)
 8,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inclusion of biological outlier values was found to bias the results of rat uterotrophic assays towards false negatives, i.e., not identify uterotrophic effects in treated populations. The present investigation was conducted to identify the background variability in the rat uterotrophic assay and to evaluate the need to exclude biological outlier values in untreated control groups. The Styrene Steering Committee (SSC) of the European Chemical Industry Council (CEFIC) co-sponsored this work with Argus Research Laboratories (Argus). The rat uterotrophic response assay originally was used as a pharmacology screen to identify estrogenic agents. Classically, 5 to 10 immature female rats (18 to 22 days of age) are administered an agent for three or four days. At sacrifice on the following day (21 to 26 days of age), the uterus is removed, weighed and a uterine weight/terminal body weight ratio calculated. This in vivo assay has been adapted for use in identifying the potential estrogenicity of chemicals, generally using 10 immature female rats per group, more closely controlling the ages, and adding one or more positive control groups to demonstrate sensitivity and response of the test system. Statistically significant increases in the positive control group means for absolute and relative uterine weights, as compared with the untreated (or vehicle-treated) means, is generally interpreted as identifying a sensitive test system. The untreated (and/or vehicle-treated) control group is then compared with the various test groups, and statistically significant increases in the mean absolute and relative uterine weights are identified as evidence of estrogenicity of the agent. Although not fully described previously, the inherent biological variability existing in both untreated and treated animals, can confound interpretation of the data, especially when numbers are relatively small. Our laboratories have identified that under controlled GLP-compliant conditions, some Wistar rats [randomly assigned (weight-ordered) to groups of ten at 22 +/- 1 days of age, and sacrificed when 26 +/- 1 days of age] in untreated control groups have high relative uterine weights that skew data distributions such that statistically significant differences are not present between untreated control and positive control groups. Based on these observations, further evaluations of untreated control and positive control (DES-DP, 2.5 micrograms/kg, b.i.d.) populations of three rat strains [Wistar--Chbb:THOM-SPF, Wistar--Crl:(WI)BR and Sprague-Dawley--Crl:CD(SD)IBS BR VAF/Plus "International Genetic Standard"] were made to define when such normal findings should be considered biological outliers, and whether outlier values should be excluded from analyses. Our data indicate that body weight is not always predictive of uterine weight, that relative uterine weight outlier values occur in each of these rat strains, and that statistically significant differences exist between groups of untreated control animals when outlier values are included in analyses. Of 98, 60 and 60 untreated control rats in the three respective strains, 11 (11.2%), 16 (26.7%) and 15 (25.0%) had relative uterine weights > or = 0.150%, and 5 (5.1%), 4 (6.7%) and 9 (15.0%) of these rats had relative uterine weights > or = 0.200%, values within the positive control range. All positive control rats attained relative uterine weights > or = 0.100%. Of 50, 60 and 60 positive control rats in the three respective rat strains, 27 (54%), 47 (78.3%) and 36 (60%) had relative uterine weights > or = 0.200%, 9 (18%), 2 (3.3%) and 7 (11.7%) had relative uterine weights > or = 0.300% and 5 (10%), 1 (1.7%) and 3 (5%) had relative uterine weights > or = 0.400%. The incidences of relative uterine weights > or = 0.300% in the positive control group may indicate the presence of high responders. Histological evaluations of uteri of positive control rats and untreated control rats with relative uterine weights > or = 0.
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PMID:Variability in the uterotrophic response assay (an in vivo estrogenic response assay) in untreated control and positive control (DES-DP, 2.5 microG/kg, bid) Wistar and Sprague-Dawley rats. 1002 4

A highly virulent strain of infectious bursal disease virus (IBDV) was isolated from the field and propagated in SPF chickens, causing up to 100% mortality. Although it still belongs to the standard serotype 1 IBD viruses, serological typing with monoclonal antibodies showed an antigenic drift in this pathogenic strain. Conventional 'intermediate' IBD vaccines are probably more antigenically related to the pathogenic strain than the mild ones and were effective in protecting SPF chickens against challenge.
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PMID:Acute infectious bursal disease in poultry: Isolation and characterisation of a highly virulent strain. 1868 6

Protective immune response of the available IBD vaccine is insufficient to fully protect against the prevailing strain of the infectious bursal disease virus (IBDV). Such a vaccination escape IBDV field isolate idenfied from Anhui province of China in December 2007, where IBD broke out at 2 weeks post vaccination. The IBDV vp2 gene was cloned into pFastBacHTA donor plasmid, followed by generation of the recombinant bacmid DNA pBac-VP2. The latter was used to transfect insect cell Sf9 with Lipofectamine to produce recombinant baculovirus vBac-VP2. The Sf9 cells infected with vBac-VP2 were stained positive against IBDV antibody using the indirect immunofluorescence assay (IFA), which was also confirmed by the detection of IBDV Vp2 protein in the infected Sf9 cells by IBDV sandwich ELISA. Western blotting revealed that the calculated protein of approximately 53 kDa was in the expressed in the insect cells. Moreover, virus-like particles (VLPs) and "inclusion body-like"structure in the infected Sf9 cells were observed under electron microscopy. We further developed an indirect ELISA for the detection of the IBDV antibodies, which was specific and sensitive. In addition, the lysates of vBac-VP2 infected cells was used to immunize 2-week-old SPF chickens, followed by challenging with the virulent IBDV, the survival rate was 30% at 14 days post primary immunization, however, the survival rate was 100% at 14 d after the booster vaccination. The ELISA antibody titers was up to 3.2 x 10(3) and neutralization antibody titer was 2536, significantly higher than those of one-shot vaccination, 8 x 10(2) and 1106, respectively. The immunized chickens did not show any clinical signs and histopathological changes of infection in 7-days trial time. The bursa/body-weight ratios were higher than those of the unimmunized control (P < 0.05). The virus-like-particle recombinant Vp2 protein expressed in insect cells promises to be a novel subunit vaccine and diagnostic reagent candidate for IBDV.
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PMID:[Recombinant Vp2 protein of infectious bursal disease virus AH1 strain expressed in insect cells: a vaccine candidate]. 2068 2

The immunopathogenesis of infectious bursal disease virus (IBDV) was investigated in different layer and broiler type chickens in comparison to highly susceptible specific-pathogen-free layers (SPF-Wh-LT) often used for experimental studies. Layer-type chickens (LT) of all genetic backgrounds showed significantly higher IBDV antigen loads in the bursa of Fabricius (BF) compared to broiler type birds (BT) (P<0.05). The variation between IBDV-infected and virus-free birds in the percentage of splenic and intrabursal B cells, T cells and macrophages differed between genetic backgrounds as well as the expression levels of cytokines. The most susceptible SPF-Wh-LT showed high levels of circulating type I IFN starting at 2 days post infection (dpi) up to 7 dpi coinciding with clinical IBD, while less susceptible birds showed a delayed response. Circulating cytokine levels were poorly associated neither with intrabursal nor with splenic mRNA expression of these cytokines. Detected cytokines varied in expression levels and timing between infected groups of different genetic background. These data suggest that variations in the activity of immune cell populations contribute to differences in infectious bursal disease between birds of various genetic backgrounds.
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PMID:The host genotype influences infectious bursal disease virus pathogenesis in chickens by modulation of T cells responses and cytokine gene expression. 2319 26

The aim of this study is to investigate the role of the purinergic receptor P2X3 in the peripheral and central nervous systems during acupuncture treatment for the visceral pain of irritable bowel syndrome (IBS). A total of 24 8-day-old Sprague-Dawley (SD) neonatal male rats (SPF grade) were stimulated using colorectal distention (CRD) when the rats were awake. The modeling lasted for 2 weeks with one stimulation per day. After 6 weeks, the rats were randomly divided into three groups of eight each: (1) the normal group (NG, n = 8); (2) the model group (MG, n = 8); and (3) the model + electroacupuncture group (EA, n = 8) that received electroacupuncture at a needling depth of 5 mm at the Shangjuxu (ST37, bilateral) and Tianshu (ST25, bilateral) acupoints. The parameters of the Han's acupoint nerve stimulator (HANS) were as follows: sparse-dense wave with a frequency of 2/100 Hz, current of 2 mA, 20 min/stimulation, and one stimulation per day; the treatment was provided for seven consecutive days. At the sixth week after the treatment, the abdominal withdrawal reflex (AWR) score was determined; immunofluorescence and immunohistochemistry were used to measure the expression of the P2X3 receptor in myenteric plexus neurons, prefrontal cortex, and anterior cingulate cortex; and, a real-time PCR assay was performed to measure the expression of P2X3 messenger RNA (mRNA) in the dorsal root ganglion (DRG) and spinal cord. After stimulation with CRD, the expression levels of the P2X3 receptor in the inter-colonic myenteric plexus, DRG, spinal cord, prefrontal cortex, and anterior cingulate cortex were upregulated, and the sensitivity of the rats to IBS visceral pain was increased. Electroacupuncture (EA) could downregulate the expression of the P2X3 receptor and ease the sensitivity to visceral pain. The P2X3 receptor plays an important role in IBS visceral pain. The different levels of P2X3 in the peripheral enteric nervous system and central nervous system mediate the effects of the EA treatment of the visceral hyperalgesia of IBS.
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PMID:Effect of electroacupuncture on P2X3 receptor regulation in the peripheral and central nervous systems of rats with visceral pain caused by irritable bowel syndrome. 2580 68

Different immunogens such as subunit, DNA or live viral-vectored vaccines against Infectious Bursal Disease virus (IBDV) have been evaluated in the last years. However, the heterologous prime-boost approach using recombinant modified vaccinia Ankara virus (rMVA), which has shown promising results in both mammals and chickens, has not been tried against this pathogen yet. IBD is a highly contagious and immunosuppressive disease of poultry that affects mainly young chicks. It is caused by IBDV, a double-stranded RNA virus carrying its main antigenic epitopes on the capsid protein VP2. Our objective was to evaluate the immune response elicited by two heterologous prime-boost schemes combining an rMVA carrying the VP2 mature gene (rVP2) and a recombinant VP2 protein produced in Nicotiana benthamiana (pVP2), and to compare them with the performance of the homologous pVP2-pVP2 scheme usually used in our laboratory. The SPF chickens immunized with the three evaluated schemes elicited significantly higher anti-VP2 antibody titers (p<0.001) and seroneutralizing titers (p<0.05) and had less T-cell infiltration (p<0.001), histological damage (p<0.001) and IBDV particles (p<0.001) in their bursae of Fabricius when compared with control groups. No significant differences were found between both heterologous schemes and the homologous one. However, the rVP2-pVP2 scheme showed significantly higher anti-VP2 antibody titers than pVP2-rVP2 and a similar tendency was found in the seroneutralization assay. Conversely, pVP2-rVP2 had the best performance when evaluated through bursal parameters despite having a less potent humoral immune response. These findings suggest that the order in which rVP2 and pVP2 are combined can influence the immune response obtained. Besides, the lack of a strong humoral immune response did not lessen the ability to protect from IBDV challenge. Therefore, further research is needed to evaluate the mechanisms by which these immunogens are working in order to define the combination that performs better against IBDV.
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PMID:Comparison of homologous and heterologous prime-boost immunizations combining MVA-vectored and plant-derived VP2 as a strategy against IBDV. 2787 99

Infectious bursal disease virus (IBDV) is one of the most important immunosuppressive viral agents in poultry production. Prophylactic vaccinations of chicken flocks are the primary tool for disease control. Widely used immunoprophylaxis can, however, provide high pressure which contributes to the genetic diversification of circulating viruses, e.g. through reassortment of genome segments. We report the genetic and phenotypic characterization of a field reassortant IBDV (designated as Bpop/03) that acquired segment A from very virulent IBDV and segment B from classical attenuated D78-like IBDV. Despite the mosaic genetic make-up, the virus caused high mortality (80%) in experimentally infected SPF chickens and induced lesions typical of the acute form of IBD. The in vivo study results are in contrast with the foregoing experimental investigations in which the natural reassortants exhibited an intermediate pathotype, and underline the complex nature of IBDV virulence.
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PMID:Identification and assessment of virulence of a natural reassortant of infectious bursal disease virus. 3020 51