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Biomedical subjects

A Eskenasy

Publications and source records attributed to A Eskenasy.

At least 127 records · Page 7Linked to original sources
PubMedDate not supplied

Qualitative and quantitative changes of bone marrow cells in sensitized rabbits.

Bone marrow of adult rabbits was dynamically investigated during the sensitization of animals with the complete Freund's adjuvant containing 10 per cent human gammaglobulins (five intramuscular injections of 1 ml adjuvant, one per week). Smears, imprints and paraffin sections from tibial and femoral bone marrow were examined in normal, unsensitized animals, and a week after the third, the fourth and the fifth antigenic stimulations. The differential count of about 10,000 elements of 20-25 smears and imprints allowed the establishment of normal and modified myelograms at each sacrificing term. A high increase in the number of monocytes, small lymphocytes and plasma cells was noticed after the third antigenic stimulation, with statistically significant values as compared to controls. The increase in the number of lymphocytes--including both T and B cells--was more marked after the 3rd antigenic stimulation, later on the proportional increase diminished, the proliferation maintaining itself "en plateau". The ratio between myeloblastic-myelocytic and erythroblastic-erythrocytic elements doubled after the third antigenic stimulation and increased up to six times after the fifth one, due to an absolute decrease of the erythroblastic-erythrocytic line.

Animals↗
PubMedDate not supplied

Ultrastructure of macrocellular (large cell) carcinomas of the lung.

The electronmicroscopic investigation of five lung tumors histodiagnosed as macrocellular carcinomas showed the ultrastructural monomorphism of large, variedly shaped neoplastic cells, lack of intercellular junctions, voluminous nuclei with many indentations of nuclear membrane, dispersed euchromatin, large and multiple nucleoli, and nuclear bodies. A reduced number of cytoplasmic organelles was characteristic for these cells, represented mainly by mitochondria, rare rough endoplasmic reticulum, free ribosomes rare Golgi vesicles and flattened tubules, and a various amount of tonofilaments. These features characterized the poorly differentiated proliferation forming these tumors. The elements of differential diagnosis from other poorly differentiated lung tumors (epidermoid and cylindrocubic) are discussed, allowing the consideration of this proliferation type with repressed differentiation and maturation as a real one in the framework of lung carcinomas.

Carcinoma, Small Cell↗
PubMedDate not supplied

Ultrastructural changes of the rabbit lung tissue during sensitization to antigens.

In order to specify the ultrastructure of changes induced in the rabbit lung tissue during sensitization to antigens - previously studied by conventional methods -, two groups of rabbits were weekly sensitized by intramuscular injections, the first group with complete Freund adjuvant (CFA) only, the second with CFA to which human gammaglobulin was added. Fragments from caudal lobes harvested six days after the 3rd, 4th and 5th injections were processed for electron microscopy. This investigation confirmed the general process of cell accumulation within alveolar walls, interlobular areas and bronchial subepithelial layers previously appreciated histochemically and morphometrically. The predominating cells in both rabbit groups were histiocytes (macrophages) of local and blood origin; a monocyte marginating an alveolar capillary was evidenced. In the rabbits sensitized with CFA only, histiocytes were largely accompanied by lymphocytes; between them some relationships may be ultrastructurally observed. An increased number of fibrils and fibroblasts was also seen in this group. The animals sensitized with CFA containing human gamma-globulin showed active plasmoblasts and plasma cells among histiocytes; this picture corresponded to the high increase of serum precipitins. These ultrastructural changes form the basis on which hypersensitivity reactions may be challenged experimentally and during human immune chronic lung diseases.

Animals↗
PubMedDate not supplied

Morphogenesis and pathogenesis of chronic lung diseases. XX. Effects of repeated hypersensitivity reactions upon experimental immuno-granulomas of the lung.

In order to analyse the effects of repeated hypersensitivity reactions upon chronic lung lesions, lung granulomas were experimentally induced in rabbits by an intravenous injection of 1 ml of the complete Freund's adjuvant added with 10 per cent human gammaglobulin. Groups of rabbits with 14- and 21-day-granulomas were intratracheally challenged with 1.000 I.U. human gammaglobulin injected two or three times at 7-9 days interval. The responses of the lung tissue were of the Arthus type with neutrophil granulocytic accumulations and proteasic action; the intensity of cell accumulations was decreasing after the 2nd and 3rd challenge. The lesional evolution after challenge showed intra- and perigranulomatous infiltrations with alkaline-phosphatase positive lymphocytes and plasma cells. The density of the intragranulomatous reticulin network developed after the hypersensitivity reactions increased progressively and was morphometrically assessed as statistically significant. Cellular and fibrillar lesions led to the restructuring of the lung tissue.

Animals↗
PubMedDate not supplied

The pulmonary lobule as a whole: a systemic approach to lobular pathology.

A systemic approach to the pulmonary lobule in health and disease is attempted. There are emphasized the lobule definition, structure and functions (respiratory, metabolic, defensive), the program of lobular structures, their relation ways, their capacity of growth and regeneration, all contributing to the relative independence and autonomy of pulmonary lobules and to their behaviour as wholes. Taking into account the characters of pulmonary lobules in health, their pathological involvement is analysed on human and experimental materials, pointing out the importance of the aerogenic component of pathogenesis in determining the first phases of lung diseases, and of the true pulmonary characters of lesions, in comparison with those induced by the parenteral penetration of agents.

Humans↗
PubMedDate not supplied

Recurring thoracal mesenchymoma.

A four-times-recurring thoracal mesenchymoma is presented. Each tumor evolved for 2-5 years before resection, the general evolution of the case being of about 30 years. Histologically, the tumors, which involved the thoracal wall presented at the same time the predominating fibroblasto-fibrocytic structure sometimes forming whirls, different mesenchymal derivatives as vessels and angiomatous formations, osseous trabeculae, chondroblastic areas, and more or less dense zones with leiomyocytes sometimes forming myomatous and myofibromatous aspects. Mitoses and nuclear atypias were very rare. The diagnosis of benign recurring mesenchymoma of the thoracal wall and pleura is discussed.

Humans↗
PubMedDate not supplied

Ultrastructural changes of alveolar cells due to intratracheally administered detergent solutions.

Ultrastructural changes following the intratracheal injection of detergent solutions are described at the lobular level in rabbits, in which the main affected components were the large granulous alveolocytes, the local source of synthesis of phospholipids participating in the formation of lung surfactant. Irrespective of their location on the internal face of interlobular septa or at the intersection of alveolar walls, these cells suffered the direct influence of the detergent solution and presented the reduction of the intracellular formation of osmiophilic lamellated bodies to its nuclear and ribosomal phases, and a rapid release of previously formed osmiophilic bodies from ergastoplasmic cisternae by means of an active membrane-vesicular flow up to exocytosis. This process achieved a more or less complete emptying of membrane-bounded vesicles which persisted after the phospholipid release. The released lamellated bodies were engulfed by macrophages. The flat membranous alveolocytes presented here and there only an increased amount of pinocytotic and transcytotic vesicles. The alveolar walls and mainly the interlobular septa were thickened, especially due to an increased amount of ground matrix, collagen proteins and sometimes collagen fibrils.

Animals↗
PubMedDate not supplied

Lung pathogenesis. I. Challenging actions and impairment of bronchopulmonary defence mechanisms (a systemic approach).

A systemic approach to challenging factors and impairment of bronchopulmonary defence mechanisms in lung pathogenesis is attempted. Challenging factors and their penetration ways in the lung tissue are emphasized and the importance of airborne agents, of structures carrying respiratory functions and their relationships are pointed out. The bronchopulmonary defence mechanisms (mucociliary apparatus, alveolar macrophages, own defence of alveolar walls, mesenchymovascular defence of the lung) and their physiological limits of reactivity are analysed. The impairment of these mechanisms due mainly to the overelicitation by challenging factors and the outpassing of superposed mechanisms are structurally analysed and the transformation of physiological means of defence into pathogenic mechanisms is pointed out. Their relationships with the dynamics of factor assemblies and the new substrates developed are emphasized in the multifactorial framework of lung pathogenesis.

Defense Mechanisms↗
PubMedDate not supplied

Isolation, culture, and some morphohistochemical features of endothelial cells of the pulmonary microvasculature.

Taking into account the quantitative and qualitative importance of endothelial cells of the pulmonary microvasculature (40 per cent of all lung mesenchymal cells, 26 per cent of all lung cells) the authors attempted their isolation, culture in vitro and specification of some morphohistochemical characters, using the method of Habliston et al. (1979). There were used guinea pigs and rabbits and a 0.5 and 1 per cent trypsin solution in a retrograde perfusion for the detachment of endothelial cells from their rbasement membranes. The obtained cells were maintained in culture for5 7--9 days and morphologically characterized; their caveolar enzymes were evidenced (Mg-dependent ATP-ase, acid and alkaline phosphatases, a.o.).

Animals↗
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Lung pathogenesis. IV. Persisting pathogens and accumulative-proliferative cellular reactions in chronic lung processes (a systemic approach).

Persistence of pathogens within lung structures is due to the co-operation of the impairment of local defence means, of the aerial concentration and of the immunopathogenic component of processes. The action of pathogens, analysed in the framework of factor assemblies determining the process sequences, induced, as the most frequent reaction, cell proliferation and accumulation with the insertion of chemotactically retained circulating cells and their homing within alveolar wall interstitia and peribronchovascular sheets. The relations between the different inserting cells and the local ones are analyzed, with emphasis upon the derepression of local mechanisms of the steady state, secondary proliferation of both local and newly inserted cells, and current evolution to fibrosis.

Allergens↗
PubMedDate not supplied

Lung pathogenesis. III. The immunopathogenic component of pulmonary processes (a systemic approach).

The pathogenetic role of hypersensitivity reactions was systemically approached in the framework of chronic lung processes. There were analysed the biphasic evolution at least of this activity (sensitization, hypersensitivity reactions, immunopathogenic mechanisms and the morphological events induced by them having or not an immune significance); these events occurring during the stereotyped dynamics of lung processes, are often repeated, and modify the pre-existing lesions, contributing to the complication and self-perpetuation of lung processes.

Antibody-Dependent Cell Cytotoxicity↗
PubMedDate not supplied

Effect of detergent solutions upon distal lung phospholipids.

Intratracheally injected acid detergent solutions induce in rabbits a predominantly bronchiolo-lobular process evolving in two steps, an epithelial and an epitheliomesenchymal one. When the acid detergent solution reached prominently the alveolar structures it determined a rapid release by exocytosis of phospholipid lamellated bodies from the large granular alveolocytes and the following engulfment by macrophages of released products (Eskenasy, 1982 b). Histochemically, the cells containing phospholipids increased in cellularized alveolar walls, the alveolar lining film appeared thickened and denser, and the accumulated free macrophages filled with phospholipid reactive granules (Landing et al. 's method). Glucose-6-phosphate-dehydrogenase activity is very intense in the cellularly thickened alveolar walls, in macrophages and in the newly formed (regenerated) bronchiolar cells. Lactate dehydrogenase activity becomes very intense in macrophages. These data complete the morphogenic events leading to the lobular pathology.

Animals↗