Macrophage migration test of guinea pigs sensitized or tolerized to metals

A simplified macrophage migration test in agarose medium was performed to detect the immuneresponsiveness of peritoneal exudate cells (PEC) and lung lavage cells (LL) obtained from guinea pigs unsensitized, skin or lung sensitized, or those tolerized to metal-containing compounds or to PPD. The migration indexes were considered either to inhibition or to potentiation of the migration, as compared with those of normal naive cells. Inhibition of cell migration occurred in animals sensitized to potassium dicromate, metal-containing fume extract or to PPD, though the responses were strictly related to where the induction procedure had taken place (lung or skin). Conversely, both PEC and LL cells from nickel sensitized animals showed either potentiation (when lung-induced) or inhibition (when skin-induced) of the migration. Animals fully unresponsive to metals revealed no alteration in the macrophage migration. It appears that most of the results obtained from the lung or skin sensitized animals showed compartmentalization of the hypersensitivity while in tolerized animals both types of cells seemed not to be affected.

Dithiocarbamate residues found on vegetables and fruit marketed in the State of Rio de Janeiro, Brazil

Foram recolhidas 466 amostras de 30 diferentes espécies de hortaliças e frutas destinadas à comercializaçäo, a fim de se determinar o teor de resíduos de fungicidas ditiocarbamatos (Mancozeb, Maneb, Propineb, Tiram e Zineb). As amostras foram coletadas junto a fontes produtoras, em uma regiäo tipicamente agrícola do Estado do Rio de Janeiro. Para as determinaçöes analíticas foi utilizado um método baseado na reaçäo colorimétrica do dissulfeto de carbono liberado pela hidrólise ácida dos fungicidas. Do total de amostras analisadas, 63% apresentaram resíduos, sendo que 24% dessas continham níveis acima dos toleráveis pela legislaçäo vigente. Dentre as 30 culturas analisadas, as hortaliças folhosas apresentaram maior incidência de contaminaçäo (70-100%). A alface e a salsa apareceram como as culturas mais afetadas, com níveis de resíduos superiores a 50% dos limites de tolerância, seguidas pela cenoura (47,4%) e tomate (38,2%). A batata-doce e o nabo näo apresentaram resíduos. É importante o monitoramento de resíduos de ditiocarbamatos, pois apesar de apresentarem baixa toxicidade, podem ser precursores de etilenotiuréia, substância de açäo cancerígena mutagênica e teratogênica