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Upon contact with airway epithelial cells, mycobacteria activate several signal transduction events that are required for induction of NF-kappaB-dependent chemokine gene expression. However, downstream signaling pathways, especially that of Ca(2+)-dependent protein kinase C alpha (PKCalpha), and in particular, the identity of the IKKalphabeta signal pathway for CXCL8 secretion in Mycobacterium bovis BCG-induced epithelial cells are still unknown. In this study, we demonstrated that the phosphoinositide-phospholipase C (PI-PLC) downstream signaling pathway is involved in M. bovis BCG-induced CXCL8 release, since A549 cells pretreated with U73122, a PI-PLC inhibitor, inhibited CXCL8 release, whereas U73343 the inactive analog had no effect. In addition, our results demonstrated that M. bovis BCG-induced CXCL8 production by A549 cells was significantly blocked by using neomycin (another well-described inhibitor of PI-PLC with a different mechanism of action), Ro-32-0432 and Ro-31-8220 (two PKCalpha inhibitors), PP1 and PP2 (two potent and selective inhibitors of the Src-family tyrosine kinases), and Bay 11-7082 (an IkappaB phosphorylation inhibitor). We also demonstrated that M. bovis BCG can rapidly induce translocation of PKCalpha from the cytosol to the membrane, and that treatment of cells with M. bovis BCG caused time-dependent increases in phosphorylation of c-Src at tyrosine 416. Finally, our studies revealed that M. bovis BCG induced the association of c-Src and IKKalphabeta during the interaction of PKCalpha and IKKalphabeta. Altogether, these results represent the first evidence to date suggesting that M. bovis BCG activates the PI-PLC/PKCalpha/c-Src/IKKalphabeta signaling pathway to induce CXCL8 release in human epithelial cells.  相似文献   
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The O-chain polysaccharide of the lipopolysaccharide from the bacterium Naxibacter alkalitolerans strain YIM 31775(T) was characterized. The structure was studied by means of chemical analysis and 2D NMR spectroscopy and shown to be built up by the following tetrasaccharide repeating unit: -->3)-alpha-D-FucpNAc-(1-->2)-beta-D-Quip3NHBu-(1-->2)-alpha-D-Rhap-(1-->)-beta-D-Galp-(1--> where HBu is hydroxy-butanoyl.  相似文献   
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This study investigated whether long-term feeding a high-fat diet (HFC) has an effect on schistosomiasis mansoni outcome compared to standard chow diet (SC). Swiss Webster female mice (3 wk old) fed each diet over 5 months, and then were infected with 50 Schistosoma mansoni cercariae. Their nutritional status was assessed by monitoring growth rates twice a week and measuring serum levels of lipoproteins. Mice were euthanised 63 days after infection. Parasitological and liver histological analyses were performed. The levels of TC, HDL-C and LDL-C, fecal and tissue schistosome eggs were statistically different (p<0.05) between groups. Livers from HFC mice showed exudative, exudative/exudative-productive, exudative-productive and productive granulomas, some degree of hepatic steatosis and focal necrosis. Mice fed normal-chow did not present productive granulomas and hepatic steatosis. The morphometric evaluation of hepatic granulomas did not reach statistical significance (p>0.05) between diets assayed. The high-fat diet for long-term produces effects on schistosomiasis mansoni outcome.  相似文献   
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Biomechanics and Modeling in Mechanobiology - Scaffolds are microporous biocompatible structures that serve as material support for cells to proliferate, differentiate and form functional tissue....  相似文献   
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The use of radio frequency identification (RFID) technology is common in animal‐monitoring applications in the wild and in zoological and agricultural settings. RFID is used to track animals and to collect information about movements and other behaviors, as well as to automate or improve husbandry. Disney's Animal Kingdom® uses passive RFID technology to monitor nest usage by a breeding colony of northern carmine bee‐eaters. We implemented RFID technologies in various equipment configurations, initially deploying low‐frequency (LF) 125 kHz RFID and later changing to high‐frequency (HF) 13.56 MHz RFID technology, to monitor breeding behavior in the flock. We installed antennas connected to RFID readers at the entrances of nest tunnels to detect RFID transponders attached to leg bands as birds entered and exited tunnels. Both LF‐RFID and HF‐RFID systems allowed the characterization of nest visitation, including the timing of nest activity, breeding pair formation, identification of egg‐laying females, participation by nonresidents, and detection of nest disruptions. However, we collected a substantially larger volume of data using the increased bandwidth and polling speed inherent with HF‐RFID, which permitted tag capture of multiple birds simultaneously and resulted in fewer missed nest visits in comparison to LF‐RFID. Herein, we describe the evolution of the RFID setups used to monitor nest usage for more than 7 years, the types of data that can be gained using RFID at nests, and how we used these data to gain insights into carmine bee‐eater breeding behavior and improve husbandry.  相似文献   
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This study analysed the seasonal and intradiurnal behaviour of fungal spores from Alternaria and Cladosporium on air samples collected in the city of Almeria (SE Spain), as well as the influence that meteorological parameters have on the concentration of these type of spores. Aerobiological sampling was made during four years (1998-2001) using a Hirst-type volumetric spore trap. Spores of Alternaria and Cladosporium were detected throughout the year, reaching the highest concentrations from May to October. The diurnal patterns of these taxons reflected a presence similar of spores during a 24 h period, with values horary close to 4% of total sampling daily. The correlations show a positive association with temperature, hours of sunshine and accumulate rainfall, but negative with daily rainfall.  相似文献   
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