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Excessive neutrophil infiltration of the lungs is a common contributor to immune-related pathology in many pulmonary disease states. In response to pathogenic infection, airway epithelial cells produce hepoxilin A3 (HXA3), initiating neutrophil transepithelial migration. Migrated neutrophils amplify this recruitment by producing a secondary gradient of leukotriene B4 (LTB4). We sought to determine whether this two-step eicosanoid chemoattractant mechanism could be exploited by the pathogen Pseudomonas aeruginosa. ExoU, a P. aeruginosa cytotoxin, exhibits phospholipase A2 (PLA2) activity in eukaryotic hosts, an enzyme critical for generation of certain eicosanoids. Using in vitro and in vivo models of neutrophil transepithelial migration, we evaluated the impact of ExoU expression on eicosanoid generation and function. We conclude that ExoU, by virtue of its PLA2 activity, augments and compensates for endogenous host neutrophil cPLA2α function, leading to enhanced transepithelial migration. This suggests that ExoU expression in P. aeruginosa can circumvent immune regulation at key signaling checkpoints in the neutrophil, resulting in exacerbated neutrophil recruitment. [ABSTRACT FROM AUTHOR]

Anaerobic systems produce biofuels and liquid waste known as bioles. In Sistemas Biobolsa® we evaluated anaerobic fermentation of cattle and pig manure for two months. The difference between the types of cattle and porcine biol obtained was determined by the One Factor Analysis of Variance and the physical and chemical parameters were evaluated. In bioles we daily monitored pH, temperature, electrical conductivity (EC), dissolved oxygen (DO), oxide reduction potential (ORP), total dissolved solids (TDS), percentage of sodium chloride, volatile solids (VS), total solids (ST.), ash, moisture, P, PO4, P2O5, N, Na, K, Ca, Mg, Zn and Cu in its ionic form. With a pH meter (HANNA HI-255) we determined pH, EC, TDS, NaCl, and with a multiparameter analyzer (HACH, HQ40d) OD and redox potential we evaluated. With gravimetric methods, we determined humidity, ST, SV, and ash; we measured macronutrients (P, P2O5, PO4, ammonia nitrogen (NH3-H) and K+) with a nutrient analyzer (HANNA HI-83215 ) and micronutrients with an atomic absorption spectrophotometer (GBC AA 904). All analyses were performed in duplicate. The Sistemas Biobolsa® showed stability in its operation, in mesophilic conditions (variation of ±3σ in each parameter). There was a significant difference in Ca and Mg between types of excreta. Cattle biol showed 8.94 4mS cm-1, 658.9, 80.90 and 581 ppm in CE, NH4+, PO43- and K+ respectively while in porcine boil were 8.4 mS cm-1, 745.0, 39 and 521 ppm. The nutrients content of both bioles allows to be applied as fertilizers. [ABSTRACT FROM AUTHOR]