Passive Aseptic Calcification of Fixed Pericardial Biomaterials Is Mediated by Damage to the Structure and Microarchitectonics of Their Extracellular Matrix

Biophysics - Abstract—The mechanism of passive (independent of recipient cells) aseptic calcification of pericardial materials fixed with gluteraldehyde, which are used for the manufacture of...     

Characteristics of visual perception in seven-year-old children differing in functional maturity of brain structures

Individual and age-related characteristics of visual perception as a whole and its individual components were studied in seven-year-old children as related to their brain functional development. A dependence was found between the success of visual perception and the characteristics determining the functional maturity of both the cerebral cortex and the brain regulatory structures. Difficulties in noise resistance, visuospatial perception, and visual analysis/synthesis were greater in first-year school students with signs of immaturity of the bioelectrical activity of the cerebral cortex. Poor development of the visual perception system in schoolchildren was also determined by an underdeveloped frontothalamic regulatory system and deviations in the functional state of the nonspecific activation system.     

Genetic differentiation of Altai-Sayan endemic Hedysarum theinum Krasnob. (Fabaceae) evaluated by inter-simple sequence repeat analysis

The objective of the research described in this paper was to evaluate the level of genetic variability and differentiation between the populations of Hedysarum theinum Krasnob., endemic species of Altai-Sayan Mountains. In this study, six inter-simple sequence repeat (ISSR) primers were used and generated a total of 132 molecular markers, 126 of which were polymorphic (95.5%). The large amount of DNA polymorphism at the intrapopulation level (H _pop/H _sp = 70.5) was evidenced by the analysis of a molecular variance (AMOVA) of 88.2%. The high genetic similarity (I = 0.875) detected between the populations of H. theinum reflects the strongly restricted endemic range of H. theinum, which facilitates the gene flow among populations and outcrossing. Due to the significant genetic diversity revealed among individuals against a background of moderate population differentiation collecting samples for ex situ H. theinum conservation from a small number of populations is acceptable. Finally, selected highly polymorphic ISSR markers produced consistently repeatable patterns are discussed as a powerful tool for genotype identification and the qualification of root feedstock.     

Comparative Assessment of the Functional Activity of Rat Epididymal Mitochondria in Oxidative Stress Induced by Hyperhomocysteinemia and L-NAME Administration

Journal of Evolutionary Biochemistry and Physiology - The state of protein carbonylation with the determination of the adaptive reserve potential and analysis of the proportion of primary and...     

Aggregation of Nanosized Hydroxyapatite Particles and Inhibition of Cell Adhesion on this Bio-Active Material as Key Factors that Limit its Biointegration

Biophysics - Abstract—Different synthetic calcium phosphate compounds are used as osteoplastic materials for filling of bone defects during surgical reconstruction of bone. Synthetic...     

Bioelectric brain activity during visual perception of verbalized and nonverbalized stimuli in seven-to eight-year-old schoolchildren

Neurophysiological mechanisms of visual perception of verbalized and nonverbalized stimuli have been studied in girls (n = 89) and boys (n = 109) aged seven to eight years. It has been shown that, in children of this age, neurophysiological mechanisms of the visual perception system during the selection of verbalized and nonverbalized stimuli have similar organizations of functional rearrangements and are characterized by the general involvement of cortical areas and by the lack of clear specialization of the cerebral hemispheres. However, the choice of nonverbalized visual stimuli is characterized by a more pronounced generalization of the functional interaction between cortical areas and by the increased spectral power of the EEG’s high-frequency components in anterior associative areas. The increased spatial synchronization in the EEG θ- and β bands in the frontal areas emphasizes the contribution of these structures to the analysis and processing of visual stimuli at this stage of development. Differences in the neurophysiological mechanisms of visual perception in boys and girls have been detected. Spatial and temporal organizations of bioelectric activity (BEA) of the brain in girls performing visual tasks is characterized by a stronger and more varied ipsi- and contralateral statistical relationships in the fronto-occipital direction and displacement of interaction centers to the left hemisphere. In boys perceiving verbalized and nonverbalized visual stimuli, a greater contribution of posterocentral cortical areas has been observed. The detected differences are considered to reflect a greater maturity of identification mechanisms in girls aged seven to eight years as compared to boys.