Publications by authors named "I B Afanas'ev"

The purpose of the work is to study the possibility of using carbon nanotubes (CNT) as taggants in gun powder to provide expert differentiation of used small firearms cartridges; and to identify the main characteristics of the changes to carbon nanotubes under firing conditions, i.e. short-term exposure to high temperatures and pressures.

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Superoxide is a precursor of many free radicals and reactive oxygen species (ROS) in biological systems. It has been shown that superoxide regulates major epigenetic processes of DNA methylation, histone methylation, and histone acetylation. We suggested that superoxide, being a radical anion and a strong nucleophile, could participate in DNA methylation and histone methylation and acetylation through mechanism of nucleophilic substitution and free radical abstraction.

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It has been shown that ROS (reactive oxygen species, superoxide and hydrogen peroxide) regulate major epigenetic processes, DNA methylation and histone acetylation, although the mechanism of ROS action (ROS signaling) is still unknown. Both DNA methylation and histone acetylation are nucleophilic processes and therefore ROS signaling through typical free radical processes, for example hydrogen atom abstraction is impossible. However, being "super-nucleophile" superoxide can participate in these reactions.

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The use of up-to-date diagnostic methods for the examination of 72 patients presenting with grade II-III arterial hypertension and high risk of cardiovascular complications made it possible to estimate the state of brachiocephalic arteries before and after combined antihypertensive therapy that continued during 14 days. The following variables were measured: blood flow rate, peripheral vascular resistance indices at the extra- and intracranial levels, metabolic indices of cerebrovascular responsiveness, and coefficient of variability as an indicator of the cerebrovascular reserve capacity under conditions of antihypertensive treatment. Three antihypertensive therapeutic regimens were employed, viz.

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This work considers reactive oxygen species (ROS) signaling in solid tumors. Most (probably all) cancer cells are characterized by ROS overproduction that is they exist under conditions of incessant oxidative stress. For example ROS overproduction has been shown in prostate, pancreatic, melanoma, and glioma cells.

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