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This review analyzes the general patterns of synergism, whose manifestation under the simultaneous actions of various agents does not depend on the biological objects and the effect being analyzed. The existence of an optimum temperature that provides the maximum synergy for simultaneous application of hyperthermia with various physical or chemical agents is demonstrated. Examples of the dependence of synergism on the intensity of electromagnetic radiation applied simultaneously with a fixed elevated temperature are given. It is shown that the synergistic effect of interaction of these factors with hyperthermia increases as the intensity of applied agents increases, reaches a maximum, and then decreases. A biophysical interpretation of this original dependence of synergism on the intensity of the used agents is suggested. This interpretation is based on the idea that the formation of additional lethal changes as a result of the interaction of sub-lesions underlies the mechanism of synergistic interaction.

The search for efficient radioprotective substances that alleviate various effects of ionizing radiation has been going on for more than 6 decades. The chronology of the major discoveries in this field and the changes in opinions, trends, and paradigms are considered in the present review. Various classes of chemical compounds that can be administered either before or after irradiation to protect biological objects from short- and long-term effects of ionizing radiation are considered. Dose-modifying factors, recommended time of administration, tissue specificity, and the toxicity of different classes of radioprotective substances are considered and the mechanisms that underlie the actions, as well as the practical applications, of these substances, are described. A section of this review is dedicated to future prospects and the directions of research on radioprotective substances.

Isotopic effects of deuterium in water are studied in a broad range of concentrations on a number of biological objects of different organization levels. The results obtained show that biological objects are sensitive to variations of isotope composition in water. A decrease or increase in deuterium concentrations in water may cause activation or inhibition of biological functions. The values of biological isotopic effects of low deuterium concentration may even be higher than those of high deuterium concentration. No regularity in response for all the objects studied failed to find out in a range of deuterium concentration in water from 4 ppm to 1%.

A method for quantitative assessment of the metabolite concentrations in digital phantoms of the biological objects has been proposed. The objects under consideration are expected to have a complex geometry of diffusive sources. We present an algorithm for calculation of non-steady state gradients of the diffusing compounds under their constant border concentration. The algorithm is based on the analytical solutions for a centrally symmetric spherical source. Spatial-time distribution of metabolites is considered by the example of glucose diffusion around blood vessels in the rat brain pial. It was shown that glucose level in the tissue was increased after glycine treatment and under condition of other biological system parameters to be unchanged.

It was found that water preliminary activated with vector potential changes mobility of infusoria brought into it, the rate of sugar fermentation in yeast cells and the drinking attractivity of water for mice. It was also shown that water physical parameters changed after water activation: UV absorption spectrum and state of a silica admixture. It was supposed that water is the initial target when weak electromagnetic fields have an influence on biological objects.

The effect of properties of liver lipids on the interrelation between the contents of different lipid fractions has been studied on nine groups of intact SHK female mice. To reveal interrelations, lipids were divided into four groups depending on their antioxidative activity, prooxidant properties, antiperoxide activity, and the content of peroxide in lipids. The data obtained indicate that the physicochemical properties of lipids affect the biosynthesis and degradation of phospholipids, which plays a significant role in the origination of consequences under the action of unfavorable factors on biological objects having the different intensity of oxidative processes.

Chronic effects of low doses of low-intensity ionizing radiation (IR) on biological objects have gained great social significance. This has given a considerable impetus to research into the biological effects and mechanisms of such exposures, both in Russia and abroad. In this paper, an overview of the physicochemical and molecular basis of IR influence at low doses is provided. Means of cell protection from radiation damage are studied and an analysis of the typical features and differences in the radiation effects at low and high doses is carried out. We considered DNA radiation damage, both in cell cultures and in vivo, as well as the processes and results of their repair. Particular attention is paid to changes in the basic paradigms of biological radiation effects at low doses.

Possible mechanisms of action of weak combined magnetic fields on biological systems have been discussed in terms of quantum mechanics. The approaches proposed make it possible to solve the problem of the failure to compare the energy of active factors with the energy of thermal motion (kT problem). A mechanism of action of combined magnetic fields on biosystems has been proposed.

The potential of atomic force microscopy for estimating geometric characteristics of blood cells is demonstrated. Comparison of hemocyte morphometric characteristics recorded using different scanning modes has demonstrated that noncontact and semicontact imaging are adequate for studying the size and geometry of biological objects. A contact scanning of cells leads to their irreversible deformation.

We generalize the results of multiyear studies of the level of antioxidative activity of lipids isolated from tissues of laboratory rodents of different species and lines. A classification of lipids according to their ability to inhibit thermal autooxidation of methyl oleate is proposed. The involvement of lipids in low-temperature autooxidation reactions at the radical initiation and chain propagation stages was proved using the model developed. In addition to antioxidative activity, the initial content of peroxides in lipids, determined by their degree of unsaturation, and the antiperoxide activity of lipids are proposed for quantitative estimation of the kinetic characteristics of lipids of mammalian tissues. The dependence of effects on the rate of radical initiation in the system is shown, which is determined by the influence of the physicochemical properties of lipids on the coordination of relationships and balance of biochemical functions in biological objects differing in the intensity of oxidation processes.