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PubMedDate not supplied

Scanning electron microscopy of normal cells, dyskaryotic cells and malignant cells exfoliated from the uterine cervix.

The same exfoliated benign, dyskaryotic and malignant cervical cells were observed by light microscopy and scanning electron microscopy in order to investigate the reflection of the course of malignancy in the surface ultrastructure. The surface ultrastructural features (microridges and microvilli) of normal squamous cells and metaplastic cells showed regularities, with an approximately even thickness, length and distribution of microvilli. In dyskaryotic cells of the superficial type, the microridgelike structure was retained, and some regularity of the microvilli remained. However, in dyskaryotic cells of the deep-layer type, the microvillous surface ultrastructure had a pronounced irregularity and diversity. In malignant cells, there was unevenness in the projections and in the thickness of the cytoplasm, and these cells presented, as a whole, a bizarre appearance. The surface ultrastructure of malignant cells thus reflected a strong atypia of the cytoplasm.

Carcinoma in Situ↗

PubMedDate not supplied

Histopathological and electron microscopical studies on experimental Penicillium marneffei infection in mice.

Experimental Penicillium marneffei infection in mice was investigated histopathologically and by electron microscopy. Viable conidia (5 x 10(6) cells) of P. marneffei were inoculated into each mouse of group A (BALB/c mice) and group B (BALB/c-nu/nu-SIc mice) through the tail vein. All the mice were sacrificed at intervals and the livers were examined. In group A, the conidia were phagocytosed by Kupffer cells soon after inoculation, and proliferated by fission in the cytoplasm. Marked proliferation of yeast cells was observed 7 and 14 days after inoculation. With proliferation of the fungus, the number of lysosomes in Kupffer cells increased, and numerous granulomas were formed in the liver. These granulomas consisted mainly of macrophages with yeast cells, together with a few polymorphonuclear leukocytes, lymphocytes and giant cells. From 28 days on yeast cells were gradually cleared from the granulomas, and 56 days after inoculation almost all the granulomas disappeared. In group B, at an early stage of infection, similar pathological changes to those seen in mice of group A were observed. However, as the infection progressed, the number of granulomas continued to increase and yeast cells continued to proliferate although lymphocytes did not infiltrate these granulomas. With proliferation of yeast cells the liver tissue was replaced with both yeast cells engulfed by macrophages and extracellular yeasts, and dissemination occurred.

Animals↗