The pathogenesis of experimental pulmonary aspergillosis. An ultrastructural study of alveolar macrophages after phagocytosis of a flavus spores in vivo

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Growth in vitro of cells from hyperplastic nodules of liver induced by 2-fluorenylacetamide or aflatoxin B1

Cell suspensions obtained from hyperplastic nodules induced in rat liver by either of the two hepatic carcinogens, 2-fluorenylacetamide or aflatoxin B(1), show growth when cultured in vitro. No growth of cells from liver adjacent to the hyperplastic nodules or from liver of control rats has been obtained so far under comparable conditions. Hepatocarcinoma cells induced by 2-fluorenylacetamide grow readily in vitro but behave differently. These findings suggest that some nonmalignant cells capable of growth in vitro arise during liver carcinogenesis prior to the appearance of unequivocal cancer. Cultures of such cells may offer new avenues for the study of liver carcinogenesis.

Studies on the interstitial cells of the testis. 3. The ultrastructure in the immature mongolian gerbil and the effect of stimulation with human chorionic gonadotropin

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Studies on the interstitial cells of the testis. II. The ultrastructure in the adult guinea pig and the effect of stimulation with human chorionic gonadotropin

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Lysosomal stability during phagocytosis of Aspergillus flavus spores by alveolar macrophages of cortisone-treated mice

Control mice and those treated with cortisone were exposed to aerosols of viable spores of Aspergillus flavus. Fifteen to 20 minutes later, animals were killed, and alveolar macrophages were obtained by tracheobronchial lavage. Electron-microscopic examination of these cells revealed that, whereas the lysosomes of control macrophages showed extensive attraction and fusion with the phagocytic membranes surrounding spores, the lysosomes of macrophages from animals treated with cortisone revealed little, if any, interaction. This diminished lysosomal response in forming phagocytic vacuoles may be important in the subsequent development of hyphal bronchopneumonia which frequently, occurs in cortisonetreated mice exposed to spores of A. flavus.