Morphofunctional study of blood polymorphonuclear leucocytes in HIV-Seropositive individuals

The impairment of leukocytic functions in AIDS infected individuals, where opportunistic infections are manifested, has been under study since 1985. However, controversy remains concerning leukocyte function during initial stages of HIV infection. In the context of the precarious immunologic and phagocytic defense of persons with AIDS, and the resulting difficulty they have to control microorganism invasion and oportunistic infections, examination of the host defense functions played by leukocytes in seropositive HIV persons is particularly important. To that end, our study sought to assess, during the initial stage of HIV infection, the laboratory parameters associated myeloid cells which are known to be altered during disease stage. Seventy-five (75) persons seropositive to HIV-1 (by the ELISA test, confirmed by immunofluorescence), and twenty-six (26) controls were tested. These individuals were screened by infectologists and their disease severity classified according to the Walter Reed Army Institute System. We observed that myeloperoxidase enzyme activity, superoxide anion production, and fungicidal action in homologous serum were all diminished in patients classified as WR-1, and progressively decreased in Wr-2-4. The percent phagocytizing neutrophils and the number of C. albicans phagocytized were normal in WR-1 patients, but diminished in WR-2-4. We conclude that neutrophil function is diminished in HIV-infected persons at the beginning of infection, and that the defects increase as the HIV disease progresses.

Inibidores da agregacao plaquetaria induzida pelo PAF-acether / Inhibitor of the platelets aggregation induced by the PAF-acether

O efeito do PAF-acether foi avaliado em plaquetas humanas de individuos adultos clinicamente saudaveis atraves de estudos em plasma rico em plaquetas (PRP) com inibidores plaquetarios "in vitro"(AAS, NDHA e CP/CPK) e "ex-vivo" (AAS). O PAF-acether induziu agregacao dose dependente em concentracoes de 5x10-9M a 5x10-7M, com dose limite ou threshold em 9x10-8M. Os resultados obtidos demonstraram que a fase primaria de agregacao e independente da formacao de metabolicos de acido araquidonico e liberacao de ADP endogeno visto que, com excessao do BN 52021, os demais inibidores nao influenciaram nessa fase. Por outro lado, a fase secundaria de agregacao irreversivel envolve interrelacao entre os mediadores ADP e Acido Araquidonico dependentes preferencialmente da formacao de metabolicos do acido araquidonico via ciclo-oxigenase.