RESUMEN
Laws mandating phosphorus (P)-based nutrient management plans have been passed in several U.S. Mid-Atlantic states. Biosolids (sewage sludge) are frequently applied to agricultural land and in this study we evaluated how biosolids treatment processes and biosolids P tests were related to P behavior in biosolids-amended soils. Eight biosolids generated by different treatment processes, with respect to digestion and iron (Fe), aluminum (Al), and lime addition, and a poultry litter (PL), were incubated with an Elkton silt loam (fine-silty, mixed, active, mesic Typic Endoaquult) and a Suffolk sandy loam (fine-loamy, siliceous, semiactive, thermic Typic Hapludult) for 51 d. The amended soils were analyzed at 1 and 51 d for water-soluble phosphorus (WSP), iron-oxide strip--extractable phosphorus (FeO-P), Mehlich-1 P and pH. The biosolids and PL were analyzed for P, Fe, and Al by USEPA 3050 acid-peroxide digestion and acid ammonium oxalate, Mehlich-1, and Mehlich-3 extractions. Biosolids and PL amendments increased extractable P in the Suffolk sandy loam to a greater extent than in the Elkton silt loam throughout the 51 d of the incubation. The trend of extractable WSP, FeO-P, and Mehlich-1 P generally followed the pattern: [soils amended with biosolids produced without the use of Fe or Al] > [PL and biosolids produced using Fe or Al and lime] > [biosolids produced using only Fe and Al salts]. Mehlich-3 P and the molar ratio of P to [Al + Fe] by either the USEPA 3050 digestion or oxalate extraction of the biosolids were good predictors of changes in soil-extractable P following biosolids but not PL amendment. Therefore, the testing of biosolids for P availability, rather than total P, is a more appropriate tool for predicting extractable P from the biosolids-amended soils used in this study.
Asunto(s)
Fósforo/farmacocinética , Eliminación de Residuos , Contaminantes del Suelo/farmacocinética , Agricultura , Animales , Disponibilidad Biológica , Predicción , Aves de Corral , Aguas del AlcantarilladoRESUMEN
With the advent of new molecular biology and scientific techniques, there is better understanding of genetic polymorphisms in oxidative drug metabolism systems today. These systems are important in pharmacogenetic studies which genotype polymorphic alleles encoding drug metabolising enzymes to enable the individual's drug metabolising phenotype to be found. Once found, the knowledge can be used to tailor drug dosage regimens to an individual to maximise therapeutic efficacy and minimise adverse drug reactions (ADRs). The knowledge could also be used to optimise drug development programmes so that all the subgroups within a target population are adequately represented in clinical trails.
Asunto(s)
Hidrocarburo de Aril Hidroxilasas , Quimioterapia , Farmacoepidemiología , Farmacogenética , Polimorfismo Genético , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP2D6/genética , Sistema Enzimático del Citocromo P-450/genética , Etnicidad , Genotipo , Humanos , Oxigenasas de Función Mixta/genética , FenotipoRESUMEN
OBJECTIVES: To characterise the cellular interactions and the mechanisms involved in the recruitment of inflammatory macrophages and T cells to the bone implant interface in 30 patients with aseptically loosened orthopaedic prostheses. METHODS: Cell adhesion molecules E-selectin, VCAM-1, ICAM-1 and the receptors LFA-1 and CR3 were immunolocalised on cryostat sections of the bone-implant interface obtained during revision arthroplasty. The percentage of expression on vascular endothelium was determined on serial sections. RESULTS: E-selectin was upregulated on different vessels in 21 patients. Its expression correlated strongly with the presence of metal wear debris. VCAM-1 was detected on vessels in six patients only, and was coexpressed with E-selectin in three patients with metal debris. VCAM-1 was more frequently observed in the lining cells on the implant side. ICAM-1 was upregulated on vessels on the bone side only in 13 patients, and was more strongly expressed on aggregates of macrophages and multinucleated giant cells on the implant side. These macrophage aggregates coexpressed both ICAM-1 and CR3. CONCLUSION: Our findings implicate the contribution of three different pathways in the recruitment of inflammatory cells to the joint in response to orthopaedic implant wear particles. The association of E-selectin expression and metal debris may suggest hypersensitivity reactions. Finally, the simultaneous expression of ICAM-1 and CR3 on the same macrophages on the implant side may predict an additional function of these molecules in homotypic adhesion/cell aggregation that precede differentiation of phagocytes to multinucleated giant cells.