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Biomedical subjects

V A Vasil'eva

Publications and source records attributed to V A Vasil'eva.

At least 19 recordsLinked to original sources

Quantitative changes in the fibroarchitectonics of the human cortex from birth to the age of 12 years.

Brains from 74 children aged from birth to 12 years were used to study fibroarchitectonic characteristics in topographically and functional diverse cortical zones (the temporal-parietal-occipital subregion, occipital, precentral, postcentral, and frontal areas) of the cerebral cortex; children aged up to 12 months were studied on the basis of one-month age intervals. Studies were performed by computer analysis of optical images on frontal sections stained with Nissl cresyl violet and silver nitrate impregnation by the modified Peters method. Data on the rate of increase in the thickness of radial bundles of fibers, the distances between bundles, and the age dynamics of the ratios of the specific volumes of neurons and fibers in fields 3, 4p, 6op, 17, 19, 37ac, 44, and 32/10 were obtained. These measurements showed that age-related transformation of fibroarchitectonics in fields of the sensorimotor, somatosensory, occipital, temporal-parietal-occipital, and frontal areas occurred at different times and with different intensities; the most significant changes were seen in the first 2-3 years of life, with changes continuing at a less intense level to age 9-12 years.

Age Factors↗

[Quantitative changes in fibro-architectonics of the human cerebral cortex from birth to 12 years of age].

The peculiarities of fibroarchitectonics in topographically and functionally distinct cortical zones (including temporo-parieto-occipital subarea, occipital, pre-, postcentral, and frontal areas) were studied in the brain specimens of 74 children of different ages (from birth to 12 years) taken with yearly intervals, while those in the first year of life--with monthly intervals. Frontal sections stained with Nissl, Peters and Golgi methods were studied using computer analysis of optical images. The data were obtained on the increment rates of radial fiber fascicles' thickness, distances between fascicles and age dynamics of ratios of volume densities of neurons and fibers in areas 3, 4p, 6op, 17, 19, 37ac, 44 and 32/10. It was shown that age-related transformations of fibroarchitectonics in the areas of sensomotor, somatosensory, occipital, temporo-parieto-occipital and frontal cortex were heterochronic and took place with different intensity; most pronounced changes were found to occur during the first 2-3 years, while less intensive ones were observed up to the age of 9-12 years.

Aging↗

[Characteristics of the functional organization of neuronal groups in functionally diverse zones of the human cerebral cortex from birth to 20 years of age].

Using computer analysis of histological specimens of motor and posterior associative cortex of the man aged from birth up to 20 yrs age and individual peculiarities of focal groups sublayer III3 of areas 4p, 6op and 37ac, periods of intensive and slow growth of the area of profile fields (PF) of cell groups and total area (TA) of neurons in the group were established. It was shown that greater changes of cell groups PF area and neuron TA occurred in the area 4p during first 3 yrs, while in areas 6op and 37ac from birth up to 7 yrs and 8-9 yrs appropriately. Specific features of the group development in functionally different areas of human brain cortex was demonstrated.

Adolescent↗

[Characteristics of the ensemble organization of the human cerebral cortex from birth to 20 years of age].

When studying frontal, somatosensory and visual areas of the human cerebral cortex from birth up to 20 years of age in year-to-year intervals, it has been stated that by birth in neocortex all components of the neuron-glio-vascular ensembles are presented. They are not connected in their composition. During the first year of life the size of all types of neurons increases, long-axonal basket neurons differentiate, fasciculi of radial fibers become thick. By 3 years of life in the ensembles the neurons are definitely grouped as clusters. Sizes of spindle-like and satellite neurons increase; they distribute their axonal collaterals vertically, horizontally and in frontal-posterior direction. By 5-6 years of age the horizontal connection system becomes more complex at the expense of longitudinal growth and ramification of lateral and basal dendrites of the pyramidal neurons. In the section transversal areas occupied with cell groups increase. By 9-10 years of age the pyramidal neurons reach their greatest size. By 12-14 years of age the fibrillar component of the cortex increases considerably, inter- and intraensemble horizontal connections become more complex, the system of local connections becomes more plastic owing to development of short-axonal basket-like neurons. By 16-18 years of age the ensemble cortical organization in its main parameters of architectonics reaches the level specific for mature persons.

Adolescent↗

[Amino acid sequence of Ondatra myoglobin (Ondatra zibethica). Characteristic features of myoglobins from semiaquatic animals].

Based on the amino acid composition of globin, amino acid analysis and N-terminal sequencing of peptides as well as a comparative analysis of the primary structure of beaver, coypu rat and otter myoglobins with the use of the fingerprinting technique, the amino acid sequence of the major component of ondatra myoglobin including 153 amino acid residues was reconstructed. The results of a comparative analysis of the primary structure of myoglobin and the peculiarities of the functional morphology of myoglobins from semi-aquatic animals and sperm whale and the role of amino acid substitutions in the spatial structure of ondatra myoglobin are discussed.

Amino Acid Sequence↗

[Chromosomes of 7 transplantable lines of macaque and pavian hematopoietic cells producing herpesvirus type EBV and oncornavirus type C].

Karyotypes of Su-1, Su-2, KMMA-1, and KMMA-2 (producing oncornavirus C-type), and KMPG-1, SPF-2, and SPG-3 (producing HSV, a virus of EBV type) cell lines were studied in the time course. The lines were derived from hemopoietic cells of brown macaques and baboons bearing lymphomas. Some of the lines had a paradiploid-pseudodiploid karyotype, another part aneuploid type. The selectivity of structural and numerical abnormalities of chromosomes 1, 9, 10, 11, 12, 13, 15, 18, and 20 was detected indicating a certain specificity of karyotype changes upon malignization and transformation. The number of poorly and moderately differentiating chromosomes in aneuploidy was confirmed by greater variability as compared with well-differentiating chromosomes. No parallelism between the karyotype change pattern and the type of virus produced (C or EBV) could be found thus far.

Animals↗