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Dilda F Gioia G Pisani L Restelli L Lecchi C Albonico F Bronzo V Mortarino M Ceciliani F 《Veterinary journal (London, England : 1997)》2012,192(3):514-516
MicroRNAs (miRNAs) are a family of regulatory molecules involved in many physiological processes, including activation of cells of the immune system. This study investigated the effect of Escherichia coli lipopolysaccharide (LPS) and Staphylococcus aureus enterotoxin B (SEB) on the expression of five miRNAs involved in the inflammatory response, including miR-9, miR-125 b, miR-155, miR-146 a and miR-223, in bovine CD14(+) cells (monocytes). Incubation of monocytes with SEB induced down-regulation of miR-155, miR-223 and miR-125 b, but not the anti-inflammatory miRNA miR-146 a. Conversely, incubation with LPS upregulated both miR-155 and miR-146 a. In vitro incubation of isolated CD14(+) bovine monocytes with LPS and SEB elicited different and opposite expression of miRNAs reportedly involved in inflammatory reactions. 相似文献
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Large areas assessments of forest biomass distribution are a challenge in heterogeneous landscapes, where variations in tree growth and species composition occur over short distances. In this study, we use statistical and geospatial modeling on densely sampled forest biomass data to analyze the relative importance of ecological and physiographic variables as determinants of spatial variation of forest biomass in the environmentally heterogeneous region of the Big Sur, California. We estimated biomass in 280 forest plots (one plot per 2.85 km2) and measured an array of ecological (vegetation community type, distance to edge, amount of surrounding non-forest vegetation, soil properties, fire history) and physiographic drivers (elevation, potential soil moisture and solar radiation, proximity to the coast) of tree growth at each plot location. Our geostatistical analyses revealed that biomass distribution is spatially structured and autocorrelated up to 3.1 km. Regression tree (RT) models showed that both physiographic and ecological factors influenced biomass distribution. Across randomly selected sample densities (sample size 112 to 280), ecological effects of vegetation community type and distance to forest edge, and physiographic effects of elevation, potential soil moisture and solar radiation were the most consistent predictors of biomass. Topographic moisture index and potential solar radiation had a positive effect on biomass, indicating the importance of topographically-mediated energy and moisture on plant growth and biomass accumulation. RT model explained 35% of the variation in biomass and spatially autocorrelated variation were retained in regession residuals. Regression kriging model, developed from RT combined with kriging of regression residuals, was used to map biomass across the Big Sur. This study demonstrates how statistical and geospatial modeling can be used to discriminate the relative importance of physiographic and ecologic effects on forest biomass and develop spatial models to predict and map biomass distribution across a heterogeneous landscape. 相似文献
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Germán Cantón Paul Bartley Kathryn Bartley Helen Todd Francesca Chianini Frank Katzer 《Veterinary immunology and immunopathology》2013,151(3-4):342-347
Pro-inflammatory cytokines (particularly IL-12) are important for initiating protective T helper 1 (Th1)-type immune responses and hence vital for combating intracellular infections and tumours. In situ hybridization (ISH) provides a powerful diagnostic tool allowing the identification and localization of cells producing these mediators in fixed tissues. The objective of this work was to produce a bovine IL-12p40 probe that allows detection of IL-12p40 mRNA in fixed tissues from different ruminant species. The RNA probe sequence is 447 bp in length and from a region with high cross-species-sequence homology (>97.3% homology) to the ovine, cervine, caprine and bubaline IL-12p40 genes. ISH was carried out on paraformaldehyde fixed tissues collected from cattle, sheep and goats. The probe was efficient in identifying IL-12p40 expressing cells in fixed tissues from all these species. In conclusion, the IL-12p40 probe was efficient in identifying and localizing cells that express IL-12p40, and provides a good immuno-diagnostic technique to characterize immune responses in fixed tissues. 相似文献
57.
Narayan Chandra Paul Francesca Latronico Arshnee Moodley S?ren Saxmose Nielsen Peter Damborg Luca Guardabassi 《Veterinary research》2013,44(1):52
The current knowledge of in vitro adherence of Staphylococcus pseudintermedius to canine corneocytes is limited to comparative analyses between strains, staphylococcal species or corneocytes collected from different breeds, body sites and hosts. However, the role played by colonization status of corneocyte donors remains unknown. The aim of this study was to evaluate the adherence properties of commensal S. pseudintermedius strains to corneocytes collected from dogs with different colonization status. For this purpose, corneocytes were collected from five dogs that were classified as persistently colonized (D1 and D2), intermittently colonized (D3 and D4) or non-colonized (D5) on the basis of the results of a previous longitudinal study. Adherence to corneocytes originating from each of the five dogs was assessed by an in vitro adhesion assay using four genetically unrelated strains isolated from the colonized dogs (S1 to S4). Irrespective of their host of origin, all strains adhered significantly better to corneocytes from D1 and D2 than to corneocytes from D3, D4 and D5 (P < 0.0001). The mean count of cells adhering to corneocytes from persistently colonized dogs was on average three times higher than the mean count using corneocytes from the other dogs. A significant difference between strains was only observed for one strain-corneocyte combination (S2-D4), indicating that S. pseudintermedius adherence to corneocytes is driven by host factors and only marginally influenced by strain factors. This finding has important implications for understanding and preventing S. pseudintermedius skin colonization and infection. 相似文献
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Masino F Montevecchi G Arfelli G Antonelli A 《Journal of agricultural and food chemistry》2008,56(20):9495-9501
In this study, two different doses of commercial beta-glucanase enzyme preparation were tested to verify their effect on wines aged on lees. These wines were compared with two samples with no enzymatic treatment. The former was aged on lees (control), and the latter was readily filtered off from the yeast cell biomass (standard). Analysis of variance (one-way ANOVA), the Tukey test, and principal component analysis (PCA) were applied to all of the samples, which were analyzed for aroma composition, along with galacturonic acid, total acidity, pH, and color. Results showed a large number of statistically significant differences among samples. In general, wines treated with beta-glucanase were characterized by higher concentration of many volatile compounds. The presence of lees and even more the exogenous enzymatic action enhanced almost all volatile compounds. Besides the high presence of ethyl esters, it is worth mentioning the behavior of hexanol and trans-3-hexenol, which are strongly enhanced by the presence of lees and by enzymatic treatments. 相似文献
60.
Vesper HW Slimani N Hallmans G Tjønneland A Agudo A Benetou V Bingham S Boeing H Boutron-Ruault MC Bueno-de-Mesquita HB Chirlaque D Clavel-Chapelon F Crowe F Drogan D Ferrari P Johansson I Kaaks R Linseisen J Lund E Manjer J Mattiello A Palli D Peeters PH Rinaldi S Skeie G Trichopoulou A Vineis P Wirfält E Overvad K Strömberg U 《Journal of agricultural and food chemistry》2008,56(15):6046-6053
Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered. 相似文献