Alveolar fibrosis and capillary alteration in experimental pulmonary silicosis in rats.

To analyze the evolution of fibrotic and vascular changes in pulmonary silicosis, ultrastructural and immunohistochemical studies were made of the lungs of rats given a single intratracheal injection of silica particles. Early lesions were characterized by accumulations of macrophages and neutrophils in alveolar lumina and interstitium and by damage to alveolar capillaries and epithelial cells. The intraluminal masses of inflammatory cells developed into granulomas and became associated with myofibroblasts that migrated from the interstitium through the damaged epithelial lining.

[A correlative study of the aluminum content and aging changes of the brain in non-demented elderly subjects].

The interrelation of the aluminum content and aging change of the nerve cells was studied with special reference to the neurofibrillary tangle (NFT) and occurrence of senile plaque (SP), in 15 autopsied brains (cerebrum) of non-demented elderly subjects varying in age from 75 to 101 years old and 10 cases of non-demented non-elderly adult subjects. 1) In the brain of non-demented non-elderly adult subjects, the aluminum content of the hippocampus was 14.4 +/- 1.

[Adhesion ultrastructures of mononuclear cells in experimentally-induced silicotic granuloma].

Experimental silicosis was induced by intratracheal infusions of 1 ml saline containing 50 mg standard silica (less than 5 microns diameter) in Sprague-Dawley rats. The lung tissues were observed histologically and ultrastructurally from half an hour up to 4 months. Macrophages, neutrophils, desquamated cells and their debris piled up around the alveolar ducts where the central cores of silicotic granuloma appeared.

[Study of abscopal effect and cellular infiltration of tumor nests using less-fractionated, large-dose radiation].

As reported by several authors, abscopal effect and favorable cellular infiltrations into the tumor nest caused by irradiation suggest the existence of cell immunity in the host. In our present study, as first step to elucidate the mechanism of the fact mentioned above, effects of radiation with a single dose irradiation was estimated in terms of the increase of survival rate and the inhibition of pulmonary metastasis, i.e.