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L N D'iachkova

Publications and source records attributed to L N D'iachkova.

At least 19 recordsLinked to original sources
PubMed2003

[Morphology of the rat's brain in and after a space flight: ultrastructure of the "blue spot"].

Electron microscopy was used to explore ultrastructure of the livor extracted from the brain of rats on day-13 aboard U.S. space shuttle Columbia (STS-58), and in 5-6 hrs. after landing following the 14-d mission. As compared with the ground controls, the rats flown in microgravity reduced the total number of axodendrite synapses (ADS) by 21% and functional ADS--by 39.7%. After touchdown the total ADS number remained lowered by 16.5%; however, the percentage of highly active ADS exceeded this parameter in the ground controls. Results of the analysis of the ADS number in conjunction with the ultrastructural changes in axonal terminals and dendrites suggest a sharp decrease of the afferent influx towards the livor neurons during microgravity, whereas modifications of the livor neuron ultrastructure point to a decline in their functional activity. These data serve as an experimental proof of the hypothesized development of the hyponoradrenergic syndrome by mammals in microgravity.

Animals↗
PubMed2002

[Morphometric study of yeast cells of Torulopsis sphaerica after He-Ne-laser irradiation].

A study was made of structural organization of Torulopsis sphaerica cells irradiated with He-Ne (lambda = 632.8 nm; dose--460 J/m2) and then cultured in the nutrient with 1% glucose and O2 for 6 h. The computer analysis of electron images of cell sections was carried out. Evidences of stimulation of cell proliferation were found, including decrease in the areas of cell and chondriome profiles, decrease in the number of mitochondria on sections, elongation of cells and mitochondria, and increased variability of cell parameters. In addition, cells of irradiated cultured were characterized by the increase in the number of mitochondria contacting the endoplasmic reticulum (in this case the outer mitochondrial membrane presumably associates with the ER membrane), which may suggest the activation of ATP synthesis. Thus, He-Ne laser irradiation activates cell metabolism even at the early stage of culture growth.

Candida↗
PubMed1979

[Laminar analysis of the synaptic organization of the frog optic tectum].

Distribution of axo-axonic and axo-dendritic synapses, nervous terminals and neuron somata in the depth of the optic tectum was studied in frog Rana temporaria L. in norm and 6-9, 60 and 134 days after contralateral eye enucleation. In outer plexiform layer 9 density of synapses was found to be maximal near the surface of the tectum; it decreased in deeper levels. In the outer zone of layer 9 (about 0.30 micrometer from the surface) many axo-axonic synapses were found. Terminals of myelinated optic fibres of large diameter ("dark" terminal degeneration) were widely distributed in layer 9. Density of axo-dendritic synapses in deep plexiform layer 5 was similar to that in layer 9. Numerous nervous terminals containing not only light synaptic vesicles, but also granular vesicles were seen in layer 5 and in adjacent zones.

Animals↗
PubMedDate not supplied

[Intermittent exposure to hypergravity of rats deprived of support to the hind limbs. analysis of the somatosensory cortex ultrastructure].

Intermittent hypergravity was evaluated as a method to prevent the unfavorable nervous effects of microgravity. It was shown that intermittent exposure to hypergravity (2 G, 1 h. a day) of rats during 24-d tail-suspension put a barrier to changes in the ultrastructure of the brain somatosensory cortex associated with a reduction in the afferent input to the somatosensory cortex from the hind limbs.

Animals↗