Histology and histopathology Vol. 2, nº 3 (1987)
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- PublicationOpen AccessCytostatic action of methylmercuric chloride on mammalian duodenal cells(Murcia : F. Hernández, 1987) Curle, D.C.; Ray, M.; Persaud, T.V.N.; Bertalanffy, F.D.Adult male mice of the ICRISwiss Webster strain received a single intragastric administration of methylmercuric chloride 1,000 ppm, at dose levels of 5,10,15,20,25 and 30 mglkg of body weight. The animals were killed six hours later. Tissue samples from the duodenum were fixed in 10% neutral buffered formalin for light microscopy. Chromosome clumping was observed in dividing cells at all dose levels, resembling a C-mitotic effect. It would lead to reduced mitotic cell formation on account of the subsequent lysis of the arrested metaphases. The cytostatic effect was brought about by the inactivation of the microtubule spindle fiber polymerization mechanism induced by methylmercuric chloride. There was a direct positive correlation between the varying dose levels of methylmercury and the proportion of cells arrested in metaphase in the crypts of the duodenum.
- PublicationOpen AccessUltrastructural study of granulomatous tissue in tonsillar malakoplakia(Murcia : F. Hernández, 1987) Vitellaro-Zuccarello, L.; Felletti, V.; Paizis, G.; Spinelli, M.
- PublicationOpen AccessScanning electron microscopy of human and murine melanoma cells exposed to medium chain-length, C6mC,2d i carboxylic acids in tissue culture(Murcia : F. Hernández, 1987) Breathnach, A. S.; Robins, E. J.; Bhasin, Y. P.; Ethridge, L. B.; Nazzaro-Porro, M.; Passi, S.; Picardo, M.Human and murine (Harding-Passey and Cloudman) melanoma cells were exposed to various concentrations (1 X 10-3M-l X 10-lM) of adipic (C,), azelaic (C,), and dodecanedioic (C,,) acids for 1-6 hours in tissue culture, and the effects on shape and surface topography were examined by scanning electron microscopy. Effects, i.e., rounding up, concentration of microvilli, blebbing, and prominence of retraction fibrils were time and dose dependent, and for the same concentrations and exposure times, C,, had a greater effect than C,, and both a significantly greater effect than C,. These differential reactions to the three diacids parallel previously reported effects on cell kinetics and viability. The changes could be due to a prime effect on the cell membrane, or they might reflect phases of the cell cycle directed by action of the diacids on the nucleus; this latter seems unlikely. An effect on the cytoskeleton is possibly involved.
- PublicationOpen AccessAn ultrastructural examination of murine alveolar macrophages following intranasal administration of Propionibacterium acnes(Murcia : F. Hernández, 1987) Hightower, James A.; Welsh, Marcia G.; Jackson, R.A.; Gangemi, J. DavidLight and electron microscopic analysis of murine lungs or isolated pulmonary cells was performed three days after intranasal administration of the bacterial immunostimulant, Propionibacterium acnes (P. acnes). Our observations indicated that pulmonary alveolar and airway macrophages (PAMs) were the only cells with P. acnes bacilli in their cytoplasm. Bacilli were not observed in pulmonary interstitial macrophages, granulocytes, lymphocytes or pulmonary parenchyma1 cells such as type I and type I1 pneumocytes. Because of the morphological heterogeneity of PAMs observed in control and experimental animals, it was not possible from these studies to be certain about the relative abundance or complexity of lysosomes, endoplasmic reticulum, Golgi and other organelles in the two groups. However, we noted that it was not uncommon to observe in the same PAM, profiles of P. acnes and a well developed Golgi complex and endoplasmic reticulum. These P. acnes - associated morphological alterations occurred at a time when functional activities (e.g., phagocytosis, cytostasis) of PAMs were enhanced.
- PublicationOpen AccessMononuclear cell subpopulations and infiltrating lymphocytes in erythema dyschromicumperstans and vitiligo(Murcia : F. Hernández, 1987) Gross, Ana; Tapla, F.J; Mosca, Walter; Perez, Ricardo M.; Briceño, Luis; Henriquez, Juan J.; Convit, J.