RESUMO
The aim of the present theoretical study is to examine the dioxygen activation process occurring at the metalloporphyrin complexes as the first step of the selective oxidation of hydrocarbons, with the stress put on how this may be affected by the type of the central metal. In order to do so, the properties of the porphyrin complexes of Mn, Mo, and Co are discussed by means of quantum chemical calculations within Density Functional Theory (DFT). As a first step, the dioxygen binding by the above-mentioned systems is considered, followed by the study of the interactions of one and two hydrogen atoms with different types of the adsorbed O2 molecule onto the porphyrin complex. Finally, the stability of the formed oxo species is discussed.
RESUMO
Pesticides and their metabolites are excreted mainly by the kidneys. The effect of these compounds on the kidney parenchyma was evaluated on the basis of determinations of the activity of the following enzymes: alkaline phosphate, N-acetylglucosaminidase, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase and arginase in urine of workers employed at the department producing organophosphorous pesticides (32 males and 53 females) as well as those employed at the production of chlorfenvinphos (35 males). The activity of most of the estimated enzymes was significantly higher as compared to control groups. The dynamic of changes of enzyme activity was traced in the workers employed at the department producing chlorfenvinphos over their first 18 months of employment.