Electron paramagnetic resonance spectroscopy has been applied for the first time to study the bio-distribution of magnetoliposomes formed with magnetite nanoparticles (Fe3O4) in tumors and organs of Lewis carcinoma-bearing mice in the absence and presence of an external magnetic field. The animals of the experimental group were subjected to an external magnetic field (0.6 T) in the tumor area after

Abstract Penetration of a microelectrode into the cell soma is one of the most vulnerable stages of the method intracellular recording. Traumatic neuronal activity after piercing the membrane with a microelectrode can be an indicator of neuronal damage. In this paper we report the results from tests of our pulse electromagnetic micromanipulator. This device is designed to reduce the neuronal damage

Several models of long short-term memory (LSTM) neural networks were constructed. Each model was trained on the complete mouse genome to predict the exon–intron structure of a gene. The performance of the neural networks was compared using a test sample and experimental sequencing data obtained using rat brain cell cultures after treatment with spicing inhibitors.

Abstract Gold nanoparticles are promising radiosensitizers for proton radiotherapy. However, the physical mechanisms of gold nanoparticles radiosensitization remain unclear. In the present study, the Geant4 toolkit was used to estimate by the Monte-Carlo simulation the changes (1) in the contribution of primary and secondary particles to the absorbed dose, (2) in the dose-averaged linear energy transfer

The DBSCAN clustering algorithm, an in-house method of unsupervised machine learning, was used to explore specific histotopographical features of the megakaryocytic lineage in the bone marrow biopsies of patients with JAK2- or CALR-mutated essential thrombocythemia and prefibrotic primary myelofibrosis. Ninety-five bone marrow biopsies of patients with essential thrombocythemia and primary myelofibrosis

Studies on the effects of an electromagnetic field on the activity of recombinant luciferase in the luciferase–luciferin–ATP-Mg2+ system were conducted. The enzymatic activity was evaluated by the measurements of biochemiluminescence intensity with a standard chemiluminometer. Frequencies that effectively caused irreversible changes in the enzyme activity were identified. The intensity of chemiluminescence

High organoprotective properties of a carbon monoxide (CO)–oxygen (O2) gas mixture were confirmed after prolonged (24-h) preservation of the papillary muscle and an isolated rat heart at 4°C. Hypothermic preservation in the high-pressure gas mixture (6 atm) provided efficient restoration of the contractile activity of the isolated rat heart after 24-h storage at 4°C. The isolated retrograde-perfused

Ligand binding to DNA duplexes in a DNA biosensor was studied in conditions where the number of ligand molecules in the solution fluctuates under the influence of a fluctuating medium (external noise). A multiplicative stochastic differential equation was obtained for the case of low occupancy to describe the time-dependent change in the number of ligands absorbed on DNA duplexes. The average value

We have studied the contrast sensitivity of the visual system in various ranges of the spatial frequencies in “dry” immersion conditions that simulate the physiological effects of microgravity. The contrast sensitivity in the range of low and high spatial frequencies is indicative of the functional state of the magnocellular and parvocellular neuronal pathways that form the dorsal and ventral information

Abstract This study deals with participation of isoquinoline derivatives of coumarin in the peroxidase reaction catalyzed by the cytochrome c–cardiolipin complex. We have studied coumarin derivatives called coumarin-314 (C-314), coumarin-334 (C-334) and coumarin-525 (C-525). These substances are considered as specific physical activators of chemiluminescence, which accompanies the lipid peroxidation

Nanoparticles with a high atomic number are of interest as radiosensitizers for radiation therapy of cancer. A variety of nanoparticles and radiation sources makes the challenge of selecting their optimal combinations to achieve maximum irradiation efficacy relevant. In this work, we calculated the values of the dose enhancement factors of elemental compositions of metal oxide nanoparticles (Al2O3

The cellular mechanisms of pacemaker-cell activity and the contribution of various ion channels of the embryonic heart are not yet fully understood. This paper presents the results of an experiment to study the effects of specific ion-channel inhibitors on the generation of action potentials in pacemaker cells of the right atrium in chicken embryos. It has been found that the exclusion of calcium ions

The appropriateness of verification of the possible antiviral effect of dinitrosyl iron complexes with thiol-containing ligands as donors of nitrosonium cations (NO+) is argued. There is reason to hope that treatment of the human respiratory tract and lungs with sprayed solutions of dinitrosyl iron complexes with glutathione or N-acetylcysteine (NAC) ​​as NO+ donors during COVID-19 infection can initiate

This review is focused on literature data and our own research of the nontrivial quinoid pathway for the oxidation of adrenaline. All catecholamines can be oxidized similarly with formation of corresponding aminochromes. This process is simulated in vitro in an alkaline medium and is known as the adrenaline autoxidation chain reaction, whose products are adrenochrome and radical compounds, superoxide

Abstract The involvement of natural radicals in single-electron processes of cell activity is considered. It was shown that coenzymes that have intermediate free radical quinoid and semichinoid forms can interact with carotenoids to form complexes with a charge transfer with an absorption band of 1030 nm. Moreover, the complex can perform an active light-harvesting function during photosynthesis up

Much attention is given to research and development of efficient systems for the delivery of essential omega-3-polyunsaturated fatty acids and other nutraceuticals to the human body with food. Nanocomplexes, which are based on soybean phosphatidylcholine liposomes with nutraceuticals included, are among the efficient delivery systems. The prolonged use of these nanocomplexes may affect the antioxidant

We investigated the effects of the H2S and CO gasomediators on Ca2+-dependent potassium channels and an anion exchanger, which participate in the induction of the hyperpolarization response of the erythrocyte membrane and play an important role in regulation of the volume and deformability of erythrocytes. We showed that in the presence of H2S and CO donors, the amplitude of the redox-stimulated membrane

Abstract A hypothesis is proposed that the cytokine storm syndrome, which complicates COVID-19 in some patients, is a consequence of antibody-dependent enhancement of virus infection, which is in turn happens due to a change in dominant antigenic determinants of SARS-CoV-2 S-protein. The antibody-dependent enhancement of virus infection is a phenomenon in which virus-specific antibodies that are not

The effects of radiation from the young Sun and galactic cosmic rays on the physical conditions on the early Earth are significantly underestimated in studies of the problems related to the origin and evolution of the biosphere. This review considers the dynamics of solar and galactic processes over the 4.56 billion years of the existence of the Solar System. These factors substantially affected the

This study demonstrates the susceptibility of the Escherichia coli and Bacillus subtilis planktonic bacteria to inactivation by shock acoustic waves that arise from the rapid formation and collapse of vapor bubbles in a medium locally heated to its boiling point. Local heating of the medium occurred due to heat release through the relaxation of highly excited electronic states of exogenous molecules

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