Influência das práticas de manejo orgânico e convencional na qualidade do solo em produção familiar de hortaliças.

Este estudo teve objetivo de avaliar indicadores físicos e biológicos do solo que, inseridos no Módulo complementar “Capacidade produtiva do solo”, avaliem o impacto das práticas agrícolas sobre diferentes manejos do solo. Para efeito comparativo e complementar, serão avaliados os indicadores químicos. Análises de parâmetros químicos, físicos e biológicos foram realizadas em cinco propriedades de cada sistema, orgânico e convencional, selecionadas em Ibiúna e Socorro, SP. Em todas as propriedades, os indicadores físicos estabilidade de agregados, aeração e compactação contribuíram para os impactos ambientais (IA) negativos, conseqüência do baixo aporte de matéria orgânica diversificado, solos descobertos e com excessiva mecanização do solo. Este fato foi complementado pela presença de mofo branco (Sclerotinia sclerotiorum) e redução da atividade microbiana no solo

Leaf Spectra Changes of Plants Grown in Soils Pre- and Post-Contaminated with Petroleum Hydrocarbons

Leaks from accidents or damage to pipelines that transport liquid petroleum hydrocarbons (PHC) such as gasoline and diesel are harmful to the environment as well as to human health, and may be hard to detect by inspection mechanisms alone when they occur in small volumes or persistently. In the present study, we aim to identify spectral anomalies in two plant species (Brachiaria brizantha and Neonotonia wightii) linked to contamination effects at different developmental phases of these plants. To do so, we used spectroscopy and remote sensing approaches to detect small gasoline and diesel leaks by observing the damage caused to the vegetation that covers simulated pipelines. We performed a contamination test before and after planting using gasoline and diesel volumes that varied between 2 and 16 L/m3 soil, in two experimental designs: (i) single contamination before planting, and (ii) periodic contaminations after planting and during plant growth. We collected the reflectance spectra from 35 to approximately 100 days after planting. We then compared the absorption features positioned from the visible spectral range to the shortwave infrared and the spectral parameters in the red edge range of the contaminated plants to the healthy plants, thus confirming the visual and biochemical changes verified in the contaminated plants. Despite the complexity in the indirect identification of soil contamination by PHCs, since it involves different stages of plant development, the results were promising and can be used as a reference for methods of indirect detection from UAVs (Unmanned Aerial Vehicles), airplanes, and satellites equipped with hyperspectral sensors

Steroid Withdrawal in Simultaneous Pancreas-Kidney Transplantation:

ABSTRACT Simultaneous pancreas-kidney transplantation (SPK) is the treatment of choice for selected diabetic patients with end-stage renal disease. Maintenance steroid therapy is associated with significant morbidity and mortality among SPK transplant recipients. Steroid withdrawal regimens are becoming more common, albeit with reservations regarding its safety and efficacy. We performed retrospective review of 77 SPK transplant recipients from May 2000 to December 2007. The subjects received induction therapy with thymoglobulin followed by maintenance immunosuppression with tacrolimus and myco- phenolate mofetil. late steroid withdrawal protocol was adopted. The rates of acute rejection, graft and patient survival, and side effects were analyzed. One-year patient, kidney, and pancreas survivals were 93%91%and 86%respectively. Eleven patients experienced acute rejection. Mean follow-up time was 1155.5 776.1 days. Prednisolone withdrawal was carried out between and 12 months posttransplantation in 42 patients (77.8%with at least year follow-up; no case of acute rejection occurred. At present, 72 patients have functioning kidney graft, and 65 patients also have functioning pancreas graft. The mean serum creatinine is 1.12 0.49 mg/dL and the mean HbA1c concentration is 4.5% 0.4%The patients have low prevalence of hypertension, hyperlipidemia, and obesity. Steroid withdrawal was successful and safe in the majority of in-study patients and safe without an increase of immune events. Our patient and graft outcomes are within other international SPK transplant units standards

Mitochondria a key role in microcystin-LR kidney intoxication

Microcystins (MCs) are a group of closely related cyclic heptapeptides produced by a variety of common cyanobacteria. These toxins have been implicated in both human and livestock mortality. Microcystin-LR could affect renal physiology by altering vascular, glomerular and urinary parameters, indicating that MC-LR could act directly on the kidney. The aim of the current work was to examine the effect of MC-LR on mitochondrial oxidative phosphorylation of rat kidney isolated mitochondria.Furthermore, microcystin-LR decreased both state 3 and carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP)-uncoupled respiration. The transmembrane potential was strongly depressed by MC-LR in a concentration dependent manner, pointing to an uncoupling effect; however, microcystin-LR did not increase the permeability of the inner mitochondria membrane to protons. Therefore, the transmembrane decrease was a consequence of a strong inhibitory effect on redox complexes. The addition of uncoupling concentrations of MC-LR to Ca2+-loaded mitochondria treated with ruthenium red resulted in mitochondrial permeability transition pore (MPTP) opening, as evidenced by mitochondrial swelling in isosmotic sucrose medium. Mitochondrial swelling in the presence of Ca2+ was prevented by cyclosporin A and was drastically inhibited by catalase and dithiothreitol, indicating the participation of mitochondrial generated reactive oxygen species in this process. From this study it can be concluded that the bioenergetic lesion promoted by microcystin-LR seems to be sufficient to explain renal injury. Copyright © 2007 John Wiley & Sons, Ltd