Marlene Fenyo Pereira

Phagocytic activity mediated via FcγR, FcμR, and CR3 and H2O2 release during ontogeny of mouse macrophages

Abstract Mouse macrophage phagocytic activity was studied during ontogenetic development by comparing the abilities of infant and adult mouse macrophages to ingest opsonized particles via FcγR, FcμR, or CR3. These studies were performed on resident, BCG-, and thioglycollate-stimulated peritoneal macrophages. The percent of ingestion and the index of maximal phagocytosis mediated via FcγR is lower in infant than in adult mouse macrophages. However, the adherence mediated by FcγR is similar to that seen with adult cells. Similar results were obtained when phagocytosis was mediated via FcμR or CR3, reaching adult levels during ontogenetic development. We also studied the age-dependent release of H 2 O 2 by peritoneal cells before and after incubation with phorbol myristate acetate. Interestingly, the capacity of peritoneal cells from infant animals to generate H 2 O 2 after BCG infection is similar to that observed in adult mice. Our results suggest that the adherence and phagocytosis mediated by FcγR, although at lower levels than in adults, and the production of microbicidal H 2 O 2 may be relevant for mouse survival during the first days of life.

Research on calcifications in the cervical region using panoramic and teleradiographic techniques

Objetivo: Avaliar a contribuicao das telerradiografias, nas normas lateral e frontal, na identificacao e localizacao de calcificacoes em tecidos moles, quando comparado com as observadas em radiografia panorâmica. Metodos: Referencias opacas em guta percha foram posicionadas unilateralmente, em tres cabecas de cadaveres, procurando manter sempre no mesmo nivel da bifurcacao da arteria carotida comum, em diferentes estruturas, sitios de possiveis calcificacoes e foram obtidas tres incidencias radiograficas para cada peca anatomica. Assim, a amostra deste estudo foi composta por 27 radiografias panorâmicas, 27 telerradiografias em norma lateral e 27 telerradiografias em norma frontal, totalizando 81 radiografias. Resultados: De acordo com os criterios de Cicchetti e Sparrow observou-se valores inferiores a 0,40 de coeficiente de correlacao intraclasse (CCI) entre os metodos. Conclusao: Foi possivel concluir que as telerradiografias em norma lateral e frontal nao contribuem eficazmente na identificacao e localizacao de radiopacidades na regiao cervical, e que a conformacao anatomica interfere na observacao da presenca de radiopacidade na regiao cervical.