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931.
The Daubenton’s bat is widespread and common in the UK and countries bordering the English Channel and North Sea. European bat lyssavirus 2 (EBLV-2), a rabies virus, has been detected in Daubenton’s bats in the UK and continental Europe. Investigating the relatedness of colonies and gene flow between these regions would allow regional estimates of the movement of Daubenton’s bats and thus the potential for disease transmission. The genetic structure of the Daubenton’s bat in western Europe was investigated by analysing variability at eight microsatellite loci. Genetic diversity was found to be high at all sites (H E = 0.73–0.84), with little differentiation between bats sampled in the UK and continental Europe. Mantel tests indicated a significant correlation between geographic distance and pair-wise F ST (P = 0.000), between colonies sampled in Scotland and northern England. However, this was not continuous throughout the sampled range, with evidence of panmixia within the area sampled in continental Europe. Assignment tests show no evidence that the (potential) EBLV-2 sero-positive and virus positive bats were more likely to have originated from the continental rather than UK populations. There is no sufficient significant genetic differentiation amongst most UK and continental colonies to conclude that EBLV-2 is maintained in the UK by immigration. Results show that it is likely to be maintained at a low endemic level within the UK. The relative genetic uniformity of UK and continental populations implies that there is no migration barrier to EBLV-2, between these regions.  相似文献   
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A proteomic analysis was conducted to map the events during the initial stages of the interaction between the fungal pathogen Fusarium graminearum and the susceptible barley cultivar Scarlett. Quantification of fungal DNA demonstrated a sharp increase in fungal biomass in barley spikelets at 3 days after inoculation. This coincided with the appearance of discrete F. graminearum-induced proteolytic fragments of β-amylase. Based on these results, analysis of grain proteome changes prior to extensive proteolysis enabled identification of barley proteins responding early to infection by the fungus. In total, the intensity of 51 protein spots was significantly changed in F. graminearum-infected spikelets and all but one were identified. These included pathogenesis-related proteins, proteins involved in energy metabolism, secondary metabolism and protein synthesis. A single fungal protein of unknown function was identified. Quantitative real-time RT-PCR analysis of selected genes showed a correlation between high gene expression and detection of the corresponding proteins. Fungal genes encoding alkaline protease and endothiapepsin were expressed during 1-3 days after inoculation, making them candidates for generation of the observed β-amylase fragments. These fragments have potential to be developed as proteome-level markers for fungal infection that are also informative about grain protein quality.  相似文献   
934.
Intramammary infusion of lipopolysaccharide (LPS) in cows induces udder inflammation that partly simulates mastitis caused by infection with Gram‐negative bacteria. We have used this animal model to characterize the quantitiative response in the milk proteome during the time course before and immediately after the LPS challenge. Milk samples from three healthy cows collected 3 h before the LPS challenge were compared with milk samples collected 4 and 7 h after the LPS challenge, making it possible to describe the inflammatory response of individual cows. Quantitative protein profiles were obtained for 80 milk proteins, of which 49 profiles changed significantly for the three cows during LPS challenge. New information obtained in this study includes the quantified increase of apolipoproteins and other anti‐inflammatory proteins in milk, which are important for the cow's ability to balance the immune response, and the upregulation of both complement C3 and C4 indicates that more than one complement pathway could be activated during LPS‐induced mastitis. In the future, this analytical approach may provide valuable information about the differences in the ability of individual cows to resist and recover from mastitis.  相似文献   
935.
3,6-Anhydro-1-(aryl or alkylamino)-1-deoxy-d-sorbitol derivatives have been prepared in four steps from isosorbide, a by-product from the starch industry. The inhibitory activities of these new compounds have been evaluated towards 13 glycosidases. A first lead-compound was identified, which inhibited β-N-acetylglucosaminidase from bovine kidney (82% inhibition at 1 mM).  相似文献   
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Background  

Studies on innate immunity have benefited from the introduction of zebrafish as a model system. Transgenic fish expressing fluorescent proteins in leukocyte populations allow direct, quantitative visualization of an inflammatory response in vivo. It has been proposed that this animal model can be used for high-throughput screens aimed at the identification of novel immunomodulatory lead compounds. However, current assays require invasive manipulation of fish individually, thus preventing high-content screening.  相似文献   
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