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Biomedical subjects

V A Tarasenko

Publications and source records attributed to V A Tarasenko.

4 recordsLinked to original sources
PubMed1984

The role of calcium ions in cytological effects of hypogravity.

Electron-cytochemical and biochemical methods made it possible to reveal certain differences in ATPase activity stimulation by calcium ions in root apex cells of pea seedlings and moss protonema Funaria hygrometrica grown under stationary and slow clinostatic (2 rev/min) conditions. It was showed that under clinostatic conditions in comparison with the control variant the ATPase activity decreases in plasmalemma. The protein content in the plasmalemma fraction was also twice as low under these conditions. The root apex cells of the pea seedlings grown under spaceflight conditions were found to contain high concentrations of membrane-bound calcium. The data obtained are discussed in relation to problems of possible mechanisms of disturbance in calcium balance and the system of active calcium ion transport through plasmalemma under hypogravity.

Bryopsida↗
PubMed1983

Biological effects of weightlessness and clinostatic conditions registered in cells of root meristem and cap of higher plants.

Research in cellular reproduction, differentiation and vital activity, i.e. processes underlying the development and functioning of organisms, plants included, is essential for solving fundamental and applied problems of space biology. Detailed anatomical analysis of roots of higher plants grown on board the Salyut 6 orbital research station show that under conditions of weightlessness for defined duration mitosis, cytokinesis and tissue differentiation in plant vegetative organs occur essentially normally. At the same time, certain rearrangements in the structural organization of cellular organelles--mainly the plastid apparatus, mitochondria, Golgi apparatus and nucleus--are established in the root meristem and cap of the experimental plants. This is evidence for considerable changes in cellular metabolism. The structural changes in the subcellular level arising under spaceflight conditions are partially absent in clinostat experiments designed to simulate weightlessness. Various clinostatic conditions have different influences on the cell structural and functional organization than does space flight. It is suggested that alterations of cellular metabolism under weightlessness and clinostatic conditions occur within existing genetic programs.

Arabidopsis↗
PubMedDate not supplied

[Electron microscopic study of protoplasts of mesophyll tobacco. I. Ultrastructural and cytochemical study of tobacco protoplasts at early stages of cultivation].

Ultrastructural changes in tobacco mesophyll protoplasts during the first three days of cultvation were studied. Localization of catalase and peroxidase activities in the freshly isolated protoplasts and 2 days after their cultivation was detected by the cytochemical 3,3'-diaminobenzidine method. A conclusion is drawn that the observed changes in the fine structure and localization of the enzymic activity are due to the following processes: reparation of disturbances caused by the isolation procedure, regeneration of the cell wall and rapid dedifferentiation of the initial parenchymatic leaf cells.

Catalase↗