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Calgranulin A (S100A8) and B (S100A9) are found at high levels in inflamed tissue and have been associated with acute and chronic inflammatory disorders. Calgranulins are discussed as damage-associated molecular patterns (DAMPs). To analyze the role of calgranulins for inflammatory responses, bovine S100A8 and S100A9 were cloned, successfully expressed and FPLC-purified. Both molecules did not induce NF-κB activation in boTLR4-transfected HEK293 cells and stimulation of bovine monocytes with both proteins did not result in interleukin 1β (IL-1β) secretion or an upregulated mRNA expression of selected genes (IL1B, TNF, CXCL8, IL10, IL12). However, Interferon γ (IFN-γ) primed bovine monocytes released significantly higher amounts of IL-1β after stimulation with S100A8, S100A9, and co-stimulation with adenosine triphosphate (ATP). In IL-4/IL-13-primed monocytes, the IL-1β release was completely abrogated. The results imply that TLR4/MyD88/NF-κB-independent S100A8/A9-mediated activation of the inflammasome in cattle is favored in a Th1 environment and that S100A8 and S100A9 act as a DAMP in cattle.  相似文献   
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Since the development of effective N2O mitigation options is a key challenge for future agricultural practice, we studied the interactive effect of tillage systems on fertilizer-derived N2O emissions and the abundance of microbial communities involved in N2O production and reduction. Soil samples from 0–10 cm and 10–20 cm depth of reduced tillage and ploughed plots were incubated with dairy slurry (SL) and manure compost (MC) in comparison with calcium ammonium nitrate (CAN) and an unfertilized control (ZERO) for 42 days. N2O and CO2 fluxes, ammonium, nitrate, dissolved organic C, and functional gene abundances (16S rRNA gene, nirK, nirS, nosZ, bacterial and archaeal amoA) were regularly monitored. Averaged across all soil samples, N2O emissions decreased in the order CAN and SL (CAN?=?748.8?±?206.3, SL?=?489.4?±?107.2 μg kg?1) followed by MC (284.2?±?67.3 μg kg?1) and ZERO (29.1?±?5.9 μg kg?1). Highest cumulative N2O emissions were found in 10–20 cm of the reduced tilled soil in CAN and SL. N2O fluxes were assigned to ammonium as source in CAN and SL and correlated positively to bacterial amoA abundances. Additionally, nosZ abundances correlated negatively to N2O fluxes in the organic fertilizer treatments. Soils showed a gradient in soil organic C, 16S rRNA, nirK, and nosZ with greater amounts in the 0–10 than 10–20 cm layer. Abundances of bacterial and archaeal amoA were higher in reduced tilled soil compared to ploughed soils. The study highlights that tillage system induced biophysicochemical stratification impacts net N2O emissions within the soil profile according to N and C species added during fertilization.  相似文献   
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Toll-like receptors (TLR) are relevant for piscine innate immunity. TLR activation recruits several downstream factors regulating the expression of immunorelevant genes. We have characterized two key factors of innate immunity from rainbow trout: MyD88 as an adaptor protein interacting directly with TLRs, and serum amyloid A as an effector molecule induced by the activated Toll-like receptor signaling cascade.Both factors share a remarkable high degree of structural conservation with their mammalian orthologs suggesting that innate immune defense mechanisms may also functionally be conserved between fish and mammals.  相似文献   
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Pathogen associated molecular patterns (PAMPs) and bacterial superantigens have many effects on mononuclear cells (MNC) and macrophages. Influences on neutrophilic granulocytes (PMN), especially by non methylated CpG motifs, gained less attention. Here we investigated whether PAMPs and the superantigen SEA have a direct or indirect influence on the survival rate of bovine PMN. Different CpG motifs, a reverse GpC motif, Lipopolysaccharide (LPS) and SEA did not result in a loss of viability of pure PMN. In the presence of MNC or in vitro generated macrophages (MdM), however, they induced an accelerated dying of PMN. The simultaneous stimulation of MNC/MdM with combinations of CpG motifs and LPS or SEA resulted in an additive or over additive effect: compared to control set ups, only 28-36% of the PMN remained viable in SEA/CpG stimulated MNC/PMN cocultures. Comparing autologous with allogeneic MNC/PMN or MdM/PMN cocultures, it showed up that not only the stimulated MNC or MdM population but also the individual reaction state of the PMN have an influence on the degree of PMN dying. Taken together, CpG motifs and other PAMPs as well as superantigens act in concert to reduce indirectly the viability of neutrophilic granulocytes and hence the functional capacity of an important effector cell population.  相似文献   
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This paper investigates how pricing efficiency of Norwegian salmon exports varies across destination market characteristics. Efficiency is defined as the rate at which individual transaction prices adjust to common market information, and is estimated by dynamic fixed effects panel models with parameters conditional on trade attributes using micro-level trade data. Our results show that contract type (Incoterms) used in transactions can be used to segment the Norwegian export markets into three types: (1) high-value trade to large distant markets, (2) medium-value trade to close high-income markets, and (3) lower-value large bulk trades to lower-income close markets. We find that pricing efficiency is lowest for committed trades over long distance using planes, and highest for less committed large bulk trades to close markets. Despite significant heterogeneity, the majority of salmon price variation (around ¾) is common, providing a clear justification for the representativeness of a salmon price index.  相似文献   
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The outcome of an udder infection is influenced by the pathogen species. We established a strictly defined infection model to better analyze the unknown molecular causes for these pathogen-specific effects, using Escherichia coli and Staphylococcus aureus strains previously asseverated from field cases of mastitis. Inoculation of quarters with 500 CFU of E. coli (n = 4) was performed 6 h, 12 h, and 24 h before culling. All animals showed signs of acute clinical mastitis 12 h after challenge: increased somatic cell count (SCC), decreased milk yield, leukopenia, fever, and udder swelling. Animals inoculated with 10 000 CFU of S. aureus for 24 h (n = 4) showed no or only modest clinical signs of mastitis. However, S. aureus caused clinical signs in animals, inoculated for 72 h-84 h. Real-time PCR proved that E. coli inoculation strongly and significantly upregulated the expression of beta-defensins, TLR2 and TLR4 in the pathogen inoculated udder quarters as well as in mammary lymph nodes. TLR3 and TLR6 were not significantly regulated by the infections. Immuno-histochemistry identified mammary epithelial cells as sites for the upregulated TLR2 and beta-defensin expression. S. aureus, in contrast, did not significantly regulate the expression of any of these genes during the first 24 h after pathogen inoculation. Only 84 h after inoculation, the expression of beta-defensins, but not of TLRs was significantly (> 20 fold) upregulated in five out of six pathogen inoculated quarters. Using the established mastitis model, the data clearly demonstrate a pathogen-dependent difference in the time kinetics of induced pathogen receptors and defense molecules.  相似文献   
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In an agricultural landscape in eastern Austria eight terrestrial organism groups were investigated as potential biodiversity indicators. We present a cross-taxon congruence assessment obtained at the landscape scale using two groups of plants (bryophytes and vascular plants), five groups of invertebrates (gastropods, spiders, orthopterans, carabid beetles and ants) and one vertebrate taxon (birds). We tested four different approaches: correlated species counts, surrogate measures of the overall species richness that was assessed, a multi-taxa (or shopping basket) approach and a simple complementarity algorithm. With few exceptions, pairwise correlations between taxa, correlations between one taxon and the species richness of the remaining groups, and correlations between a combination of the richness of two taxa and the remaining species richness were highly positive. Complementarity-derived priority sets of sampling sites using one taxon as a surrogate for the pooled species richness of all other taxa captured significantly more species than selecting areas randomly. As an essential first step in selecting useful biodiversity indicators, we demonstrate that species richness of vascular plants and birds showed the highest correlations with the overall species richness. In a multi-taxa approach and in complementarity site selection, each of the eight investigated taxa had the capability to capture a high percentage of the overall species richness.  相似文献   
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Plant Foods for Human Nutrition - Duckweeds (Lemnaceae) possess good qualitative and quantitative profiles of nutritional components for its use as human food. However, no studies have been...  相似文献   
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