Nitro-fatty acids: novel anti-inflammatory lipid mediators

Nitro-fatty acids are formed and detected in human plasma, cell membranes, and tissue, modulating metabolic as well as inflammatory signaling pathways. Here we discuss the mechanisms of nitro-fatty acid formation as well as their key chemical and biochemical properties. The electrophilic properties of nitro-fatty acids to activate anti-inflammatory signaling pathways are discussed in detail. A critical issue is the influence of nitroarachidonic acid on prostaglandin endoperoxide H synthases, redirecting arachidonic acid metabolism and signaling. We also analyze in vivo data supporting nitro-fatty acids as promising pharmacological tools to prevent inflammatory diseases.

Resíduos de tiametoxam, aldicarbe e de seus metabólitos em folhas de cafeeiro e efeito no controle de Leucoptera coffeella (Guérin-Mèneville) (Lepidoptera: Lyonetiidae) / Residues of thiamethoxam, aldicarb and its metabolites in coffee leaves and effect on the Control of Leucoptera coffeella (Guérin-Mèneville) (Lepidoptera: Lyonetiidae)

O bicho-mineiro Leucoptera coffeella (Guérin-Mèneville), uma das pragas mais importantes da cafeicultura brasileira, é controlado principalmente com inseticidas. O objetivo deste trabalho foi estudar os resíduos e a translocação do inseticida tiametoxam em folhas de cafeeiros, bem como avaliar seu efeito no controle do bicho-mineiro, comparando-o com o aldicarbe, utilizado como padrão. Para isto, foi instalado um experimento no município de Garça, SP, no período de dezembro/2001 a agosto/2002. Os tratamentos utilizados foram: aldicarbe 150 G, nas doses de 2,25 e 4,50 g i.a./cova, tiametoxam 10 GR, nas doses de 0,15 e 0,30 g i.a./cova e testemunha (sem aplicação). Amostras de ramos foram colhidas em pré-contagem e aos 30, 60, 90, 120, 150, 180, 210 e 240 dias após a aplicação, em três alturas dos cafeeiros (terços inferior, médio e superior), avaliando-se a porcentagem de folhas minadas. As determinações de aldicarbe e seus metabólitos ativos, aldicarbe sulfoxido e sulfona, e os de tiametoxam foram feitas por cromatografia em fase gasosa usando-se detector de nitrogênio-fósforo e de espectrometria de massas, respectivamente. Os resultados indicaram translocação uniforme de ambos inseticidas nos três terços das plantas de café, quando aplicados no solo. Foi constatada também, a maior persistência do tiametoxam, cujos resíduos foram encontrados até oito meses após a aplicação, enquanto os metabólitos sulfóxido e sulfona foram encontrados entre quatro e seis meses após a aplicação. Foi observado controle do bicho-mineiro pela aplicação de ambos inseticidas.

Metabolism of nitrobenzylthioinosine in leukemic cells

Nitrobenzylthioinosine [NBRT] an equilibrative nucleoside transporter inhibitor, was anabolized to its nucleotides following incubation with human erythrocytes, fresh and cultured leukemic cells. Concentration of NBMPR and its nucleotides in acute myelogenus leukemic [AML] cells were significantly higher than those in chronic lymphocytic [CLL] and chronic myelogenous [CML] leukemic cells. However, no significant correlation was found between concentration of cellular NBMPR and its nucleotides. In contrast to lymphocytes, human erythrocytes anabolized NBMPR only to NBMPR-monophosphate but no di- or triphosphate NBMPR was found following incubation of NBMPR with human erythrocytes. Phosphorylation of NBMPR in lymphocytes was almost completely inhibited in the presence of 10 micro M of adenosine kinase inhibitor, 5-iodotubercidin, indicating that anabolism of NBMPR was cayalyzed by adenosine kinase. NBMPR was stable up to 86% in plasma following in vitro incubation with whole blood obtained from leukemic patients. 6-thioinosine was the only significant metabolite of NBMPR in plasma [8% of total radioactive dose]. NBMPR was stable following overnight incubation with human purine nucleoside phosphorylase. No incorporation of NBMPR and/or its metabolites in nucleic acids was observed following overnight incubation of [3H]- NBMPR with fresh leukemic lymphocytes