This review is dedicated to the memory of Dr. Sergei L’vovich Grokhovsky, who was a distinguished scientists and experimenter; it briefly describes one aspect of his multifaceted research activity. Gro-khovsky was the first to describe the specificity of ultrasound-induced cleavage of internucleotide bonds in double-stranded B-DNA. The discovery of this new physicochemical phenomenon made it possible

Astaxanthin and its esters, which are classified as secondary carotenoids, are synthesized under stress conditions in Haematococcus pluvialis cells that undergo transformation from vegetative cells to hematocysts. Stress factors can affect not only the rate and the direction of synthesis, but also the conformational changes in the pigment molecule, causing conversion of trans-isomers to cis-isomers

It was shown that 40-min exposure of peritoneal neutrophils to hypomagnetic conditions (with a residual field of 0.01 μT) caused a significant (25%) decrease in the intensity of intracellular dichlorofluorescein fluorescence. This effect of the weak magnetic field persisted if the constant magnetic field was increased to 1 μT. Upon further increase of the field to 2.5 μT, the effect of the field disappeared

An original method for visual-differential analysis of conformational features in (bio)macromolecular structures is applied to theoretical study of the differences between the structural organizations of the D and L chiral forms of diphenylalanine nanotubes. Common features in the spatial organization of the inner surfaces of nanotube channels are described: The mirror positions of hydrophilic atoms

Cryopreservation of fish and amphibian eggs is still an unsolved problem. The formation of ice crystals inside and outside cells acts as a main detrimental factor during a deep freezing of fish eggs, as well as crystal growth (recrystallization and repeated crystallization). Designing efficient cryoprotective media is necessary in order to avoid egg injury from freezing. Additional components that

AbstractThe effect of temperature on the kinetics of erythrocyte hemolysis induced by tert-butyl hydroperoxide and dinitrosyl iron complex with thiosulfate ligands was studied. The inverse of the time needed to achieve 50% hemolysis was used as an estimate of the rate of hemolysis. This has afforded us an opportunity to present the obtained experimental data in the form of linear graphs of Arrhenius

The specific characteristics of the distribution of secondary structures and coiled-coil superhelix structures were investigated for the first time, while taking the sign of chirality into account, in polypeptide chains of proteins belonging to eight functional classes: viral proteins, chaperones, oxidoreductases, hydrolases, structural proteins, proteins involved in exocytosis and endocytosis, and

Bees, wasps, and ants have no specialized receptors for the perception of an electric field. An appropriate response to naturally occurring electric fields in bees and ants is associated with atmospheric exposure, amplified by the approach of the front of a thunderstorm. The primary transducers of mechanoreceptors that respond to displacement are related to the perception of low-frequency electric

Abstract—The round-the-day effect of solar radiation on photoreceptors of the retina of the eye and its role in the control of the circadian rhythm of the human body within an arbitrary 11-year cycle of solar activity are considered. Processed data describing the variation of the spectral and energy characteristics of solar radiation that reach the Earth’s surface over a solar activity cycle are given

The effects of different magnesium and zinc isotopes on the enzyme activity of myosin subfragment-1 have been explored. The rate of the enzymatic ATP hydrolysis in reaction media enriched with the magnetic isotope, 25Mg, is twice as high as it is in reaction media enriched with the nonmagnetic isotopes, 24Mg or 26Mg. A similar effect of nuclear spin catalysis has been detected in the experiments with

In this paper, we discuss experimental data obtained during study of the effect of a low-frequency alternating magnetic field on the conformational transitions of human serum albumin in the presence of silver nanoparticles using fluorescence spectroscopy at different pH values. A sharp increase in the albumin fluorescence intensity was detected in the presence of silver nanoparticles; this effect changed

Sea urchins and their relatives are grouped together taxonomically in the class Echinoidea (phylum Echinodermata). Echinoids exhibit remarkable variation in their pentaradially symmetric body shape phenotypes, from spheroid tests (skeletons) in sea urchins to discoid tests in sand dollars. Researchers have speculated on the morphological evolutionary transitions among these phenotypes without reaching

The effect of terahertz radiation on the functional activity of bovine serum albumin was studied by electron paramagnetic resonance spectroscopy using spin trapping and spin probing techniques. The use of a pH sensitive imidazoline spin trap allowed us to record the change in the binding strength of albumin with nitric oxide. The change in the intensity and width of bands in the EPR spectrum of the

This review considers the basic models of mutation processes that occur during selection and drift. A basically new model was developed to describe the mutation flow through a percolation lattice of selection at the population level. Natural selection of optimal variants in the evolutionary flow of mutations was considered as a percolation filter, which acts as a physical tool that forms the mechanism

AbstractSystemic administration of N-methyl-N-nitrosourea in rats resulted in the death of retinal photoreceptors followed by differentiation of retinal Müller glial cells into photoreceptor-like cells [27]. However, mammalian Müller glial cells exhibit an extremely limited proliferative capacity, which correlates with the expression of histone γH2AX and p21 protein. These proteins are known to be

AbstractA surprisingly small number of human genes (19–20 thousand) is not consistent with a much larger number of proteins and the number of their functions. One of the factors of functional diversity is the multifunctionality of proteins. An important subclass of such proteins is moonlighting proteins, in which one polypeptide chain performs two or more functions under different conditions. Often

The effect of hypoxia on nucleated red blood cells of the black scorpionfish (Scorpaena porcus) was studied in vitro. Deep hypoxia (the oxygen concentration was less than 1 mg O2 L–1; the norm was 7–8 mg O2 L–1) led to the transition of a part of the hemoglobin molecules to the ferric state (methemoglobin). The maximum increase in the concentration of methemoglobin was 32%. The accumulation of methemoglobin

Here, we show the dependence of intracellular calcium kinetics and the duration of the action potential of cardiomyocytes on an animal’s age in multicellular preparations of the myocardium of the left and right ventricles of healthy control rats and rats with inherent arterial hypertension. In the myocardium samples from control or hypertensive rats the kinetics of the decline of free intracellular

Vascular networks possess properties of self-similarity, which allows one to consider them as stochastic fractals. The box-counting method based on calculations along the vessel centerlines is traditionally used to evaluate the parameters of the fractal structure. Such an algorithm does not allow one to consider structural differences between different bifurcation levels of the system, characterized

This paper presents new results that confirm our previous inference that the binuclear form of biologically active dinitrosyl iron complexes (B-DNICs) with thiol-containing ligands (glutathione or N-acetyl-L-cysteine) may act as a donor of nitrosonium cations, which are responsible for S-nitrosothiol formation during B-DNIC decomposition in acid solutions under both aerobic and anaerobic conditions

The methods of ultraviolet and infrared spectroscopy and quantum chemical modeling have been used to evaluate the parameters of the formation of a supramolecular inclusion complex between the flavonoid quercetin and the hydroxypropyl-β-cyclodextrin molecular container. The solubility of quercetin in water has been shown to increase by a factor of more than 50 when included in a supramolecular complex

Here, we studied changes in pain sensitivity in rats subjected to low-intensity millimeter-wavelength electromagnetic radiation (EMR MM) of 7.1 mm and 0.1 mW/cm2 in the occipital-collar region with daily exposure of 30 min over 21 days. As well, this radiation was combined with moderate electromagnetic shielding (EMS) which had the following parameters. The shielding coefficients of the constant component

Abstract—Electrically induced conformational changes of polyampholytic polypeptides associated with model metal atomic clusters on the surfaces of metal-like nanoparticle and substrate with uniform distribution of electric charge, as well as on the surface of a polarized nanoparticle, were studied using molecular dynamics simulations. The average distances between the atomic clusters bound to the polypeptide

Abstract—Using Raman spectroscopy (RS) approach in a spectral range of 1000–3000 cm–1 were used to study the conformational and structural changes that arise in the heme group and globin moiety of hemoglobin in human red blood cells at various temperatures and oxygen contents. In hypoxia, the hemoglobin conformation was shown to change as a result of the increasing contribution of hematoporphyrin pyrrole

Abstract—Biodiversity-based approaches are at the forefront of creating new varieties in soybean production. In this paper, we analyzed the natural variability in the population of cultivated soybean varieties used in breeding in the Russian Federation using genome-wide association studies. Genome regions that control the protein and oil contents in seeds, as well as productivity, have been identified

AbstractGiant-sized cells, such as the internodes of characean algae, demonstrate rapid (up to 100 μm/s) rotational cytoplasmic streaming that participates in long-distance intracellular interactions and coordinates the functional activity of organelles under a nonuniform light environment. The specific functions of intense cytoplasmic streaming remain poorly investigated. The lateral transport of

Abstract—The seasonal changes of the photosynthetic processes of phytoplankton in three reservoirs of the Zvenigorod Biological Station named after S.N. Skadovsky of Moscow State University (ZBS MSU) were studied by using chlorophyll fluorescence. It was shown that a high level of photosynthetic activity was observed in the Olgin and Pozharny reservoirs (where a high level of phytoplankton was found)

Abstract—The aim of this study was to investigate the protective effect of exogenous peroxiredoxins with ischemia–reperfusion of an isolated kidney. The study was carried out using a model of isolated rat kidney perfusion ex vivo. A recombinant peroxiredoxin 6 was injected directly in the perfusion buffer. The high-molecular-weight dye Blue Dextran 2000 and urea were added to the perfusion buffer to

Abstract—A brief review of the authors’ work on the use of low-temperature EPR spectroscopy in blood tests of patients with Parkinson’s disease and tissues of rat organs taken in experiments that simulate the early stages of parkinsonism is presented. An analysis of the obtained and published data suggests that the process of hemoglobin degradation can be included in the list of fundamental characteristics

Abstract—The receptor specificity for the A/rook/Chany/32/2015 (H5N1), A/common gull/Saratov/1676/2018 (H5N6), and A/chicken/PrimorskyKrai/03/2018 (Н9N2) strains of avian influenza virus has been studied. Using the method of surface plasmon resonance for the selected strains we obtained the values ​​of the equilibrium dissociation constants with analogues of receptors such as α2-3 and α2-6. It was

Abstract—The resistance of leukemic cells to the action of chemotherapeutic drugs is the main reason for insufficient efficacy in the treatment of acute myeloid leukemia. Microenvironmental factors play one of the key roles in the formation of the phenotype of drug resistance of leukemic cells. The elucidation of the nature of drug resistance mediated by the conditions of the microenvironment is important

Abstract—New experimental evidence is reported for the formation of supramolecular complexes of water (termed emulons), which range from 1 to 100 μm in linear dimensions, include five fractions, and have a relaxation time greater than 1 s. Optic sensors, acoustic emission, and thermal analysis were used to obtain the data. Emulon decomposition at a higher temperature generates solitons in an aqueous

Abstract—The seed bank of the Vavilov All-Russia Institute of Plant Genetic Resources (VIR) contains a wide range of landraces that were collected almost 100 years ago, in which natural selection might leave signatures through crop diversification. In this study, we analyzed 407 landraces sampled at centers of the origin of the chickpea and at sites of secondary diversity. We hypothesize that a fraction

Abstract—The activities of isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, malate dehydrogenase, and NADH:ubiquinone reductase in the mitochondrial fraction from the liver tissue of rats fed diets with different sucrose and protein contents have been measured. In animals that received a high-sucrose diet, isocitrate dehydrogenase and malate dehydrogenase activities tend to decline and α-ketoglutarate

Abstract—This paper reports an analysis of the energy profile of enzymatic catalysis. The conclusion is made that using the phenomenological Arrhenius equation and the equilibrium thermodynamic parameters of Eyring’s activated complex theory it appears impossible to adequately explain the mechanism of catalysis. In real enzyme–substrate complexes the Maxwell–Boltzmann energy distribution is dramatically

Abstract—This paper presents the results on the application of low-concentration aqueous solutions of strong electrolytes activated by glow discharge plasma for plant growth stimulation. We provide experimental evidence that these solutions can be used as an effective regulator of plant growth.

Abstract—A discrete threshold model was shown to be suitable for studying and describing unconscious reactions of the human body and, in particular, characteristics of the retinohypothalamic tract, which mediates the regulation of human circadian activity rhythms by solar radiation.

Abstract—A unified system of classification of levels of molecular structures of a living cell as the hierarchy of alternating-sign chiral structures that reflects the physical (thermodynamic/entropic) basis of intramolecular and supramolecular folding is proposed and substantiated. The tendencies for intermolecular chiral correspondences characteristic of the interactions between macromolecules of

Abstract—In the first part of this review (Biophysics, 63, 858 (2018)), the structure of H1 family linker histones, their posttranslational modifications, as well as the role of H1 histone in the formation of compact transcriptionally inactive chromatin, were considered. The second part is devoted to the role of H1 family linker histones in the structural organization of chromatin at different levels:

Abstract—Electric heating of hives can be employed to help bee colonies survive cold snaps and minimize honey consumption by bee clusters. However, since our understanding of behavioral patterns of winter bee clusters is limited, this sometimes leads to the death of a colony or induces elevated honey consumption. In this work, the physical processes within the hive environment were modeled using Comsol

Abstract—The efficiency of phosphorylation in samples of isolated rat liver mitochondria in incubation media with variable isotopic composition at deuterium contents of 6, 60, 90, 120, 150 ppm, as well as 0.1, 1 and 2%, was studied. In media with a low deuterium content (up to 60 ppm), a monotonic decrease in the ADP/O ratio was observed, while at 6 ppm its value was the same as at 60 ppm. The generation

Abstract—It is established that a medium with a reduced content of deuterium has no effect on the secondary structure of horseradish peroxidase and bovine serum albumin and caused no conformational changes in the structures of these proteins. The placement of these proteins in a buffer solution prepared based on deuterium-depleted water led to a decrease in the intensity of intrinsic tryptophan fluorescence

Abstract—MAPK and PI3K−Akt−mTOR signaling cascades regulate important cellular processes. There was developed the mathematical model that was used for the analysis of the interactions within these cascades. Stability analysis of the PI3K–Ak–mTOR signaling pathway model showed that the baseline state of the signaling pathway is metastable and signal transduction can be activated by overcritical exogenous

Abstract—We have compared the antitumor activity of aurumacryl, a new cancer drug, and several well-known cytostatics with different mechanisms of action, that is, cisplatin, cyclophosphan, 5-fluorouracil, and doxorubicin, on experimental murine solid tumor models: Lewis lung carcinoma and Acatol adenocarcinoma. Aurumacryl is more active than the listed cytostatics except for cyclophosphan. Aurumacryl

Abstract—In the late 1990s, a high probability of quasi-extinction of the pikeperch population in the Azov Sea within 35 years from 1982 to 2016 was calculated due to increases in salinity. This was based on stochastic simulations with a long-term prediction model of the dynamics of the Azov Sea pikeperch population identified from the 1950−1981 observation data, including stocks, catches, temperatures

Abstract—Ozone-photodynamic effects on tumor growth rate and oxidative modification of proteins in rat tissues were studied using a model of PA kidney carcinoma. It was shown that the developed experimental therapeutic method based on the joint parenteral intraperitoneal administration of an ozonated saline solution with a concentration of ozone in the ozone–oxygen mixture of 400 μg/L and a 0.3% solution

Abstract—A rapid increase in the concentration of free radicals and reactive oxygen species at the reperfusion stage is the most dangerous stage of ischemia–reperfusion injury. An avalanche-like increase in the level of reactive oxygen species and secondary products of free radical oxidation of biological macromolecules leads to the development of oxidative stress. The use of exogenous antioxidants

Abstract—We have analyzed the gene expression dynamics in floral transition in the CDC Frontier chickpea cultivar. We provide a model, in several versions, to predict the expression dynamics of five flowering genes, taking the expression of their regulators as an input. The models were trained using the random forest method on the previously published expression data for ten flowering genes under the

Abstract—Infrared spectroscopy is a powerful analytical method that is not completely developed in relation to biological systems as yet. Previously, this method has been successfully used to analyze secondary structures. This mini-review shows the latest advances in the study of proteins using the Fourier transform infrared technique. The application of Fourier transform infrared emission spectroscopy

Abstract—Advances in nanotechnologies and artificial methods for the synthesis of metal oxide nanoparticles with sizes of 1–100 nm raise the issue of their biological safety. Nanoparticles with a size of less than 10 nm are capable of penetrating into the bloodstream, followed by their entry into various organs, such as the brain, liver, kidneys, lungs, and spleen. Nanoparticles are a pathogenic exogenous

Abstract—Pathological changes in the cerebellum are often associated with dysfunction of Purkinje cells, which is manifested in excessive spike activity. In our experiments, the increase in the frequency of spike activity of Purkinje cells was caused by the suppression of inhibitory transmission by the GABA receptor antagonist gabazin (hydrobromide 6-imino-3-(4-methoxyphenyl)-1(6H)-pyrazinobutanic

Abstract—A new method has been proposed for processing the nonstationary rhythmogram signal recorded in the head-down tilt test (HDT). The method is based on the continuous wavelet transform of the heart rate signal with a frequency modulation component. The rhythmogram signal was shown to be a system of heart rhythm bursts of different frequency ranges. Quantitative indices were developed to analyze

Abstract—The question occurs of whether a cybernetic system that functions on the basis of algorithms can simulate, at least in principle, the behavior of natural intelligence systems. A valid answer to this question, from a mathematical viewpoint, cannot be given today. Nevertheless, here we will provide rather convincing reasoning to shows that currently existing cybernetic systems in principle cannot

Abstract—The phase relationships between heart rate variability, respiration, forearm skin blood flow oscillations (according to laser Doppler flowmetry), and finger-pad tissue blood volume oscillations (according to photoplethysmography) were analyzed in relatively healthy volunteers at rest. The degree of synchronization between phases of analyzed signals was estimated based on the value of the phase

Abstract—Here, we consider the problem of the activation of the complement system by amyloid aggregates, in particular, amyloid fibrils of the Aβ(1-40) and Aβ(1-42) peptides found in the brain of patients with Alzheimer’s disease . In 1992, based on the data on colocalization of amyloid inclusions with complement system proteins in the brains of patients with this disease, it was suggested that this

Abstract—Modeling of the human aging process was performed based on the relationship between overall viability and the processes of growth and self-renewal of tissues, which is presumably regulated by the centers of the vegetative brain. The presence of two regulatory centers, which stimulate and inhibit such growth, as well as the spontaneous degradation of the cells in those centers at different

Abstract—A spectroscopic study of the manner in which exposure to elevated temperature or intense UV radiation leads to the occurrence of lipofuscin debris in the bodies and heads of Drosophila melanogaster (vestigial) has been performed. A 1-h exposure to elevated temperature (48°C) or UV radiation led to the degradation of tryptophan residues in Drosophila bodies and heads, which is associated with

Abstract—A method for certification of soybean varieties was developed based on single-nucleotide polymorphisms. A genetic algorithm was used to select an optimal set consisting of 28 single-nucleotide polymorphisms, which was then applied to certify 243 varieties. For all varieties, unique signatures of single-nucleotide polymorphisms were obtained, which differed from the signatures of any other

Abstract—The choice of a blocking protein agent for a rapid and sensitive immunochemical assay with surface-enhanced Raman spectroscopy (SERS) was the aim of this study. An optimized metal-dielectric SERS-based nanostructure was used for enhancement of the Raman scattering by proteins; a Raman spectrometer with a wide output laser beam with a wavelength of 532 nm was used to measure the amplified optical

Abstract—Using data gathered from 40 countries throughout a historical period covering two and a half centuries, we studied the peculiarities of age-related changes in the aging rate for the countries in the world and elucidated the possibilities and limitations of the method for quantitatively measuring the aging effect according to parameters related to the analysis of population mortality. Mortality