[Morphology of experimental pneumoconiosis developing after exposure to lunar soil].

Intratracheal administration to rats of a thin fraction of lunar material delivered by the Luna-16 automatic station from the Sea of Abundance gives rise to pneumoconiosis. The disease is characterized by the formation of granulation tissue consisting of lymphoid cells, macrophages, fibroblasts and cell cooperations (rosettes), by thickening of the basal layer of the aerohematic barrier, by the development of the immune process, blockade of the terminal parts of the lymphatic network, and by the development of the fibrous process. As regards the intensity of fibrous tissue formation, the lunar material might be attributed to the group of weak-fibrogenous dust as compared, for instance, with quartz.

[Electron microscopic study of the tissue reaction of lungs exposed to quartz dust of varying dispersity].

The tissue reaction of the lungs exposed to quartz dust of varying dispersity was studied by light, transmission and scanning electron microscopy. It is suggested that specific clinical manifestations of dust pathology are related to dispersity of silica. The largest quartz-containing dust particles give rise chiefly to the development of dust bronchitis.

[Ultrastructure of the neuroepithelial cells of the respiratory portion of the lungs in experimental inflammatory diseases of the lungs].

Neuroepithelial cells (NEC) and neuroepithelial bodies (NEB) were found in the lungs of rats among cells of the alveolar epithelium. The peculiar features of NEC structure included microvilli with microfibrils penetrating deep into the cytoplasm, and a complicated structure of the endoplasmic reticulum: reticulum membrane complex. NEC's are arrayed on the alveolar basal membrane singly, in pairs and in larger numbers forming NEB.

[Morphologic features of erythrocytes in normal subjects and in anemia caused by lead poisoning (electron microscopic study)].

The methods of scanning and transmission electron microscopy were used to study erythrocytes from normal subjects and those suffering from anemia of lead poisoning genesis. Erythrocytes from normal subjects were shown to have predominantly convex-concave and biconcave shapes. An insignificant portion of ageing erythrocytes of spherical shape and decreased volume had granular surface and consolidated hemoglobin.

[Cytopharmacologic effect of using polyvinylpyridine-N-oxide in experimental silicosis].

Methods of scanning, transmission electron microscopy and cytochemistry were applied to the study of the development of experimental silicosis against the background of polyvinylpyridine-N-oxide administration. The majority of the macrophages retained their functional activity and realized quartz phagocytosis, eliminating it through the airway. Bringing the proteins on the cell surface in the fibroblasts was delayed, and formation of collagen fibers decreased.

[Fibroblast differentiation during collagen formation].

The successive differentiation in the series lymphocyte--(lymphocyte-type cell--precursor)--weakly differentiated cell (polyblast)--profibroblast--fibroblast was shown by means of scanning and transmission electron microscopy. In the focus of aseptic inflammation and in the zones of pneumosclerosis (silicosis), the ultrastructural and cytochemical cell rearrangement took place which was accompanied by the development of protein synthesizing organelles and the formation of folded surface. The collagen fibers run from the surface of the differentiated fibroblasts in the ground substance and preserve the direction of their growth with respect to the spatial position of cells.

[Cellular contacts and "cytoplasmic bridges" in the inflammation focus (scanning and transmission electron microscopic study)].

Contacts between cells in an inflammation focus were studied by the methods of scanning (raster) and transmission electron microscopy on a model of aseptic inflammation in the subcutaneous connective tissue in rats. It is shown that contacts among the cells of the connective tissue and the blood in the form of "cytoplasmatic bridges", observed in the scanning electron microscope, were not confirmed by the studies in the transmission microscope. The investigation of the "cytoplasmatic bridges" in the transmission electron microscope revealed a close adjacence of the cytolemma of the contacting cells, or a harrow space between them as wide as 10-30 micron.

[Characteristics of the terminal segments of the lymphatic system of microcirculation according to the data of scanning electron microscopy].

Lymphatic capillaries and postcapillaries in the system of the connective tissue were studied by the method of scanning (raster) electron microscopy. It was shown that these capillaries consisted of chains of ballon-shaped structures-sinuses. Lymphatic capillaries represent an open system which is communicated with the intercellular matter of the connective tissue by means of openings ensuring filtration of the tissue liquid.

[Study of aseptic inflammation using the scanning electron microscope].

A focus of inflammation in the subcutaneous connective tissue in white rats was investigated in a scanning electron microscope. Lymphocytes, polyblasts, macrophages, fibroblasts, collagenous fibres, gigantic multinuclear cells, vessels are described. Similiarity in the form and structure of the surface in agranulocytes of the blood, polyblasts and macrophages was established.

[Stimulation of fibrillogenesis in granulation tissue].

RNA synthesis by fibroblasts in healing wounds of mice and passage of the newly-formed RNA from the nucleus into the cytoplasm were studied in control mice and those treated by potassium orotate. Potassium orotate accelerated the passage of the RNA from the nucleus into the cytoplasm of the fibroblasts. Formation and maturation of the collagen fibrils in the wounds were studied by scanning electron microscope.

[The structure of fibroblasts and the fibrous structures of connective tissue according to raster electron microscopic findings].

Raster electron-microscopy investigations of the structure of fibroblasts and fibrous structures of the connective tissue of the lung, lymph nodes capsules, epicardium of the heart of rats in the norm and in experimental silicosis were carried out. It is shown that collagenous fibrillas, aggregating into fibres and bundles, form multilooped supporting carcass for the man matter. In silicosis the supporting carcass is thicker, the volume of the main matter is smaller.

[The role of several occupational factors in the development of pulmonary alveolar proteinosis (an experimental study)].

The article deals with results of morphological and electron-microscopy studies of the lungs in experimental pulmonary alveolar proteinosis in rats. The disease was reproduced in experiments on 500 animals by means of chronic inhalation of electro-welding copper-containing aerosols, condensations (smokes) which may develop under similar concentrations during electric welding. The lungs were investigated at intervals ranging from several days to two years from the beginning of the experiment, the duration of which was 9 months, the dayly exposure of the animals in inhalation cameras being three hours.