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Biomedical subjects

L B Margolis

Publications and source records attributed to L B Margolis.

80 records · Page 5Linked to original sources

[Possibility to study cell membrane topography using tritium planigraphy].

The method of tritium planigraphy was adopted for the investigation of intact cells. Conditions for the incorporation of thermally activated tritium atoms in the erythrocytes are described. The accessibility of erythrocytes hemoglobin for tritium was compared to that of free hemoglobin. By comparing specific radioactivities of amino acids it was shown that the incorporation of the label into free hemoglobin was over 100 times higher than into that in erythrocytes. The cell membrane was highly tritiated. Thus the plasma membrane protects the cell inner regions from penetration of the hot tritium atoms. Tritium planigraphy can be used for studying the cell surface topography.

Amino Acids↗

[Cell sorting using magnetoliposomes].

Liposome-entrapped ferromagnetic particles are bound to the surface of L cells. A system of circular magnets is capable of concentrating magnetoliposome-bound cells, separating them from free cells. Antibodies associated with magnetoliposomes enable to concentrate selectively the target cells. Magnetoliposomes could be used for developing a new cell-sorting system.

Animals↗

[Cell growth and motility in culture (in vitro) under microgravity conditions. The Fibroblast Experiment].

The experiment "Fibroblast" was performed in 1992 on biosatellite "Cosmos-2229" in onboard device "Biobox" designed by the order of European Space Agency. The main objective was elucidation of the mechanisms responsible for the effect of space flight factors, mostly microgravity, on cell culture. We studied time-related changes in growth, motility and some morphological characteristics of the cells in monolayer cultures on a solid substrate and in three-dimensional cultures supported by sponge gels. Studies were carried out on connective tissue cells isolated from the mouse embryos. Comparative after-flight analysis of the cell cultures exposed to space flight and of those under the normal gravity conditions (1 g) on the Earth has revealed some differences. The space flight conditions, mainly microgravity, induced marked changes in morphological characteristics and functional activity of the cultured fibroblasts: changes in the nucleus size and shape, retardation of cell growth and division rate. We believe that these changes may be due to weakening of intercellular contacts and cell adhesion to the substrate. These findings are important both for general biology and space medicine, specifically for the problems of tissue regeneration and wound healing under the conditions of long-term space flight.

Animals↗