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New remains of a Taymyr mammoth, including bones, bone collagen, hairs, skin, and soft (muscle and fat) tissues were studied comprehensively by mineralogical, spectroscopic, chromatographic, and isotope-geochemical methods. The results were used to infer the mammoth's biological age and diet, paleoclimatic conditions, and the mechanisms and degree of fossilization of the remains., (© 2024. Pleiades Publishing, Ltd.)

The significance of Yersinia pestis surface antigens in adhesiveness to specific bacteriophages has been studied with the use of two methodological approaches. It was shown that Ail protein immobilized on the surface of polystyrene microspheres (but not in the solution), can bind both the Pokrovskaya phage and pseudotuberculous diagnostic phage. YapF autotransporter interacted with both phages in a water-soluble form, but YapF bound to polystyrene microspheres interacted only with the Pokrovskaya phage. An assumption was made that Ail and YapF proteins can be the primary receptors providing non-specific reversible binding to the phages used in this work., (© 2023. Springer Science+Business Media, LLC, part of Springer Nature.)

We studied the dynamics of the red blood cell composition of Wistar male rats at rest and when swimming with a load (4% body weight) before and after administration of a succinatecontaining preparation (meso-2,3-dimercaptosuccinic acid). In rats receiving the succinatecontaining preparation, a decrease in the number of red blood cells and an increase in their volume and absolute and relative number of reticulocytes were observed at rest in comparison with vivarium control. In rats exposed to exhaustive swimming after preliminary administration of the test preparation (12 h before the test), we observed a decrease in hematocrit and erythrocyte diameter in comparison with the corresponding parameters in rats not treated with the preparation; the level of hemoglobin did not change. The pattern of changes in the cellular composition of red blood in rats at rest and during swimming against the background of treatment with the succinate-containing preparation in comparison with vivarium control is considered as a result of its effect on physical exercise under conditions of stabilization of hemoglobin and hematocrit levels, activation of proliferative activity of red bone marrow, and an increase in time of swimming to exhaustion by 2.8 times.

Despite the relatively low incidence of plague, its etiological agent, Yersinia pestis , is an exceptional epidemic danger due to the high infectivity and mortality of this infectious disease. Reports on the isolation of drug-resistant Y. pestis strains indicate the advisability of using asymmetric responses, such as phage therapy and vaccine prophylaxis in the fight against this problem. The current relatively effective live plague vaccine is not approved for use in most countries because of its ability to cause heavy local and system reactions and even a generalized infectious process in people with a repressed immune status or metabolic disorders, as well as lethal infection in some species of nonhuman primates. Therefore, developing alternative vaccines is of high priority and importance. However, until now, work on the development of plague vaccines has mainly focused on screening for the potential immunogens. Several investigators have identified the protective potency of bacterial outer membrane vesicles (OMVs) as a promising basis for bacterial vaccine candidates. This review is aimed at presenting these candidates of plague vaccine and the results of their analysis in animal models.

The mechanisms of aging are described at the molecular, cell, tissue, and systemic levels. Primary age-dependent molecular lesions activate the cell stress response to compensate for the resulting defects, but the mechanisms that recover and maintain homeostasis are gradually deteriorated. When the amount of errors reaches a critical threshold in regulatory networks, a phase transition from health to disease occurs at the systemic level. The review considers the approaches to quantitative assessment of the aging process (biomarkers of aging) and promising interventions to slow down the aging process and to reduce the risk of age-dependent diseases.

We studied the effect of hypokinesia alone and in combination with cold exposure on HR and total cholesterol content in the blood serum of Wistar, WKY, and SHR rats. Irrespectively of the season, hypokinesia was associated with a decrease in HR, which is probably a result of reduced body needs due to deceleration of metabolic processes. A significant increase in total cholesterol was found under conditions of cold exposure combined with hypokinesia, which indicates qualitative structural rearrangement of energy metabolism under the influence of environmental factors. In winter, the increase in total cholesterol concentration was more pronounced (by 51.5%) in the group of hypertensive animals. Presumably, the increase in the serum concentration of total cholesterol under conditions of hypokinesia and cold exposure is a predictor of structural changes in the heart.

The role of α-carbonic anhydrase 4 (α-CA4) in photosynthetic machinery functioning in thylakoid membranes was studied, using Arabidopsis thaliana wild type plants (WT) and the plants with knockout of At4g20990 gene encoding α-CA4 (αCA4-mut) grown both in low light (LL, 80 μmol quanta m -2 s -1 ) or in high light (HL, 400 μmol quanta m -2 s -1 ). It was found that a content of PsbS protein, one of determinants of non-photochemical quenching of chlorophyll fluorescence, increased in mutants by 30% and 100% compared with WT plants in LL and in HL, respectively. Violaxanthin cycle pigments content and violaxanthin deepoxidase activity in HL were also higher in αCA4-mut than in WT plants. The content of PSII core protein, D1, when adapting to HL, decreased in WT plants and remained unchanged in mutants. This indicates, that the decrease in the content of Lhcb1 and Lhcb2 proteins in HL (Rudenko et al. Protoplasma 55(1):69-78, 2018) in WT plants resulted from decrease of both Photosystem II (PSII) complex content and content of these proteins in this complex, whereas in αCA4-mut plants from the latter process only. The absence of α-CA4 did not affect the rate of electron transport through Photosystem I (PSI) in thylakoids of mutant vs. WT, but led to 50-80% increase in the rate of electron transport from H 2 O to Q A , evidencing the location of α-CA4 close to PSII. The latter difference may raise the question about its causal connection with the difference in the D1 protein content change during adapting to increased illumination in the presence and the absence of α-CA4.

We studied electrophysiological mechanisms of ventricular arrhythmias in dogs (n=7) under conditions of antiorthostatic hypokinesia (head-down tilt 45°). Abnormal transmural heterogeneity of repolarization in the base and apex of the left ventricle and increased dispersion of myocardial repolarization were revealed. By minute 30 of antiorthostatic hypokinesia, an increase in the duration of repolarization was revealed after a period of ventricular arrhythmia in all segments and regions of heart ventricles, which was accompanied by impairment of the pumping function of the heart. A hypothesis on the physiological role of ventricular tachycardia as a mechanism of electromechanical homeostatic stabilization in the heart was proposed. The obtained results suggest that under conditions of antiorthostatic hypokinesia, canine heart after a paroxysm of irregular ventricular tachycardia becomes more resistant to arrhythmia.

Neuroprotective activity of 2,6-diisobornyl-4-methylphenol (Dibornol) was studied under conditions of experimental focal cerebral ischemia/reperfusion modeled by intraluminal occlusion of the left middle cerebral artery for 1 h followed by recirculation. Dibornol administered in a dose of 10 mg/kg intragastrically 24 h and 30 min before and 24 h after focal ischemia/reperfusion modeling reduced the size of the brain infarction zone by 52% (48 h after recirculation) and neurological deficit by 1.7-2.4 times in comparison with that in control animals.

We studied the effect of O-((((4-hydroxy-3,5-di(1,7,7-trimethylbicyclo[2.2.1]hept-exo-2-yl) benzyl)oxy)ethyl)-O-(2-hydroxyethyl)-(1→4)-α-D-glucan (D-HES, 80 mg/kg, intravenously) and reference preparation ethylmethylhydroxypyridine succinate (EMHP-S, 50 mg/kg, intravenously) on rat survival and neurological deficit in 24 h after transient global cerebral ischemia in Wistar rats. Intravenous administration of D-HES and EMHP-S significantly increased the number of survivors by 68 and 78%, respectively, in comparison with the control group. In groups treated with D-HES and EMHP-S, the number of animals with severe neurological deficit was significantly lower and the number of animals moderate or mild neurological deficit was significantly higher than in the control group.

We studied the cardioprotective effect of 2,6-diisobornyl-4-methylphenol under conditions of myocardial ischemia/reperfusion in rats. Daily administration of 2,6-diisobornyl-4-methylphenol (100 mg/kg intragastrically) over 3 days before and 5 days after modeling of myocardial ischemia/reperfusion prevented the increase in the infarction area by almost 2 times in comparison with the control by day 5 after recirculation. The type and severity of pathological changes in ECG parameters reflecting necrotic changes in the myocardium under the action of the compound significantly decreased by day 35 of the experiment. Animal survival rate during the first 24 h after ischemia/reperfusion modeling in the experimental group was by 29% higher than in the control group.

Using a translation model of alcoholic cardiomyopathy in rats we showed the presence of an additional abnormal excitation focus in the area of the pulmonary vein lacunae in the left atrium and enhanced heterogeneity of the atrium depolarization pattern. These changes can determine electric instability of the myocardium and induce malignant heart rhythm disturbances including, sudden cardiac death.

The vertebrate fauna from the cave deposits in Imanai Cave in the Southern Urals (53°02' N, 56°26'E) has been studied. It contains 715 bones that belonged to at least 11 individuals of fossil lion (Panthera (Leo) ex gr. fossilis-spelaea). It has been established that this is one of the largest Eurasian burial sites of fossil lions. The bones were accumulated due to the natural death of animals inside the cave. The age and sex estimations have shown that at least six adult males and five adult females died there. According to the accompanying fauna, radiocarbon, geochemical, and mineralogical analyses and archaeological finds, the interval of the lion bone accumulation is determined as the first half to middle of Late Pleistocene (OIS 5-3).

The contractile function of the heart was studied in adult frogs Rana temporaria under the influence of a toxic dose of isoprenaline under conditions of natural sinoatrial rhythm and during heart pacing. The dynamics of ventricular pressure was recorded with a Prucka MacLab 2000 instrument via a catheter introduced into the ventricle through the ventricular wall. Reduced (p<0.05) parameters of the pump function (HR, maximum ventricular systolic pressure, isovolumic indices dP/dt max and dP/dt min ) and lengthening of QRS complex and QT interval on ECG attested to impairment of contractile function and electrical processes after exposure to isoprenaline. Electrical stimulation of the right atrium improved myocardial contractility and ECG parameters after the administration of isoprenaline.

Incubation of Yersinia pseudotuberculosis cells grown on a solid medium with pseudotuberculous diagnostic bacteriophage for 20 min at 37oC led to a significant decrease in the concentration of both components of the system. This effect was absent when the bacteria were grown in a fluid medium. At the same time, this incubation regimen promoted vesicle formation and typical morphological changes in bacteria grown in both surface and suspension cultures. Co-incubation of the bacteriophage with suspension of vesicles isolated from the suspension culture of Y. pseudotuberculosis grown at 10oC (but not 37oC) led to a decrease in plaque-forming activity of the bacteriophage.

The chlorophyll and carotenoid content, and the spectra of low-temperature fluorescence of the leaves, chloroplasts and isolated pigment-protein complexes in the perennial herbaceous wintergreen plant Ajuga reptans L. (bugle) in different seasons of the year were studied. During winter, these plants downregulate photosynthesis and the PSA is reorganised, including the loss of chlorophyll, possible reductions in the number of functional reaction centres of PSII, and changes in aggregation of the thylakoid protein complexes. We also observed a restructuring of the PSI-PSII megacomplex and the PSII-light-harvesting complex II supercomplex in leaves covered by snow. After snowmelt, the monomeric form of the chl a/b pigment-protein complex associated with PSII (LHCII) and the free pigments were also detected. We expect that snow cover provides favourable conditions for keeping photosynthetic machinery ready for photosynthesis in spring just after snowmelt. During winter, the role of the zeaxanthin-dependent protective mechanism, which is responsible for the dissipation of excess absorbed light energy, is likely to increase.

Nanocrystalline particles of chitin in the form of hydrosol in a concentration of 0.63 mg/ml have no effect on aggregation of human platelets and clotting time of platelet-poor plasma in coagulation tests. ADP-induced aggregation of human platelets was inhibited by these nanoparticles in concentrations of 0.63 and 1.00 mg/ml in comparison with the control. Intravenous administration of nanoparticles in a dose of 1 mg/kg to guinea pigs produced no anticoagulant effect. The nanocrystalline particles of chitin can be of interest as potential drug delivery systems.

Pumping function of the heart ventricles under conditions of electrical stimulation was examined in adult dogs and rabbits. Pacing induced different changes in intracardiac hemodynamics manifested in impairment of pumping function of the right ventricle, which is largely determined by the functional state of the left ventricle. Initially high HR in rabbits more deeply limited functional reserve of the myocardium in response to electrical stimulus and was accompanied by more pronounced disturbances of pumping function of both ventricles.

Chronotopography of atrial subepicardium depolarization has been studied in a rat model of alcoholic cardiomyopathy. Formation of independent sources of initial atrial activity has been detected in the right and left atria. These sources induced the formation of several depolarization fronts that propagated autonomously, and this can be regarded as the cause of atrial arrhythmia.

We studied the effect of pectin gel particles on endotoxemia in mice induced by restraint stress. It was shown that the concentration of LPS in mouse blood increased during restraint stress, which was associated with memory impairment. Pectin gel particles prevented the development of stress-induced endotoxemia and memory impairment in mice.

A deterministic variant of Bragg Coherent Diffraction Imaging is introduced in its kinematical approximation, for X-ray scattering from an imperfect crystal whose imperfections span no more than half of the volume of the crystal. This approach provides a unique analytical reconstruction of the object's structure factor and displacement fields from the 3D diffracted intensity distribution centred around any particular reciprocal lattice vector. The simple closed-form reconstruction algorithm, which requires only one multiplication and one Fourier transformation, is not restricted by assumptions of smallness of the displacement field. The algorithm performs well in simulations incorporating a variety of conditions, including both realistic levels of noise and departures from ideality in the reference (i.e. imperfection-free) part of the crystal.

Photosynthetic processes in the leaf lamina and midribs of Plantago media were investigated using plants grown in high light (HL) or low light (LL) conditions. The fluorescence parameters, which indicate photochemical/photosynthetic activity, were different in HL and LL grown plants, but no major differences between lamina and midribs were found. An OJIP test (chlorophyll a fluorescence transient induction) of LL grown plants, indicative of the chloroplast electron transport chain, also showed both tissues to be similar. In HL plants, a partial blockage of electron flow between Q A (the primary plastoquinone electron acceptor of PSII) and Q B (the secondary plastoquinone acceptor of PSII) was found, and this was less visible in midribs. The effective dissipation of quantum energy per reaction center (DI 0 /RC) was similar in both tissues of HL grown plants, while in the midribs of LL leaves, this process seemed to be less effective. Measurements of 13 C discrimination showed that the midrib tissues of LL and HL leaves effectively used β-carboxylation products to accumulate their biomass. Thus, the well protected activity of electron transport in midribs with their limited capacity to fix CO 2 from the air may indicate the involvement of this tissue in β-carboxylation, transport or signaling. Carbon accumulated in roots showed a lower 13 C discrimination value (more negative) than the values observed in lamina. This could indicate that roots are supplied with assimilates mostly during the light phase of the day cycle with intensive C 3 photosynthesis., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

We compared bioavailability of 4-methyl-2,6-diisobornylphenol after single intragastric administration to rats in a dose of 200 mg/kg in starch suspension and in almond oil. Absorption of 4-methyl-2,6-diisobornylphenol in the gastrointestinal tract after administration in almond oil was much more efficient than after administration in aqueous starch mucus.

Repolarization properties of ventricular myocardium were studied in anesthetized adult dogs of both sexes subjected to antiorthostatic hypokinesia (head-down tilt at 45° and 60° to the horizontal) and during recovery period (horizontal position for 15 min). The time of repolarization of ventricular myocardium during recovery surpassed the initial value, which represents an adaptive response of the heart to antiorthostasis.

The effect of treatment of Yersinia pseudotuberculosis cells with antibodies of various specificities on adhesiveness of pseudotuberculosis bacteriophage was analyzed by competitive inhibition technique. Bacteriophage adsorption to bacteria was sterically inhibited by monoclonal antibodies to protein epitopes of Y. pseudotuberculosis outer membrane. These results suggest that receptors of pseudotuberculosis diagnostic bacteriophage are localized on the LPS core of microbial cell.

Experiments on peripheral blood leukocytes from healthy donors using the biochemiluminescent method demonstrated the possibility of in vitro modulating phagocytic activity of neutrophils by cold exposure. Cold exposure at 2°C for 30 min increased phagocytic activity of cells, while slow cooling to -2°C reduced it.

We studied the possibility of cryopreservation of human blood nuclear cells under protection with inert gas xenon. A method for inducing clathrate anabiosis of leukocytes was developed that preserved the cells for practical use in biology and medicine.

Darwin's dynamical theory of X-ray diffraction is extended to the case of lateral (i.e., having a finite length in the lateral direction) crystalline structures. This approach allows one to calculate rocking curves as well as reciprocal-space maps for lateral crystalline structures having a rectangular cross section. Numerical modelling is performed for these structures with different lateral sizes. It is shown that the kinematical approximation is valid for thick crystalline structures having a small length in the lateral direction.

Activities of polygalacturonase and 1,3-β-glucanase increased in campion (Silene vulgaris) callus cells during co-cultivation with the fungus Trichoderma harzianum. This was associated with a decrease in galacturonic acid residues in the pectic polysaccharide of campion silenan and also in the production of pectin by the callus. Co-cultivation of the callus and the fungus resulted in an increase in contents of arabinose residues in the intracellular arabinogalactan and in contents of galactose residues in the extracellular arabinogalactan.

The effects of pectin polysaccharides on leukocyte migration into the oral cavity during exercise were studied. The migration and hence, counts of neutrophils in the oral cavity increased during exercise. Pectins reduced neutrophil migration into the oral cavity during exercise because of hyperstimulation of their functional activity.

The expression of D-GADD45 gene involved in DNA reparation in Drosophila melanogaster decreases with age. Overexpression of D-GADD45 in the drosophila nervous system prolongs the median and maximum life span without deterioration of the quality of life parameters (fertility and neuromuscular activity). The life span prolongation effect is due to more effective DNA reparation, as spontaneous level of DNA aberrations in the nerve tissue of larvae with D-GADD45 overexpression is reduced significantly.

Choline chloride in complex with the main cryophylactic (1,2-propanediol) preserves morphological integrity and functional activity of blood nuclears after freezing to -40 degrees C by the exponential program.

One-year monitoring of the blood metabolic parameters in residents of the North (students aged 18-20 years and scientists aged 30-59 years) showed that blood concentrations of glucose, lactate, and albumin varied in young people (18-20 years) within a greater range throughout the year than in older subjects (30-59 years), while the range of variations for triglycerides and cholesterol concentration was lesser in young subjects. Despite age-specific differences in metabolism, the seasonal dynamics of metabolite concentrations conforms to common regularities. The contribution of anaerobic glycolysis to the maintenance of energy homeostasis is greater during the fall-winter period, which leads to reduction of glycemic level to the lowest threshold normal level and to lactatacidosis. The concentrations of triglycerides increase significantly in winter, which indicates intensification of lipogenesis. Gluconeogenesis and aerobic oxidation of reserve lipids are intensified in the winter-spring period.

The duration of repolarization of subendocardial, intramural, and epicardial layers of dog ventricles was studied under conditions of volume overload of the heart in situ. Increased preload was modeled by rapid intravenous infusion of saline and rheopolygluquine. The activation-recovery interval was measured by flexible intramural electrodes inserted into the right and left ventricles. The level of preload was evaluated by the increase in left-ventricular end-diastolic pressure. The increase in preload from 11+/-6 to 26+/-10 mm Hg led to a significant (p<0.05) prolongation of the activation-recovery interval in the subepicardial layers of apex, all layers of the lateral wall, and subepicardial and intramural layers of the base of the left ventricle and in subendocardial layers of the apex and base of the right ventricle. Further elevation of the end-diastolic pressure to 34+/-11 mm Hg led to shortening of the activation-recovery interval (p<0.05) in the subepicardial layers of the apex and lateral wall of the left ventricle and in the subepicardial layers of right-ventricular base and left-ventricular lateral wall. Hence, different areas of the myocardium differently react to volume overload of the heart. Changes in repolarization length in response to preload increase are biphasic.

The DNA comet assay (neutral version) showed that irradiation of CHO cells in a dose of 1 Gy (gamma-radiation, (60)Co) is followed by an increase in the degree of DNA fragmentation. These changes were observed immediately after irradiation and on days 7-21. On days 2-4 and 23-28 after irradiation, the degree of DNA fragmentation in the descendants of irradiated cell did not differ from that in control samples. The increase in the degree of DNA fragmentation on days 7-21 probably results from induction of apoptosis. This assumption is confirmed by the study of cell death. The sensitivity of cells to repeated irradiation in a dose of 10 Gy significantly increased on days 9, 11, 16, and 18 after irradiation. However, these cells were resistant to repeated irradiation on days 21-28. Our results confirm the hypothesis that genomic instability is a selective mechanism, which mediates the formation of radioresistant cell clones.

This review concerns pectin substances, the most complex class of plant polysaccharides. For the most part, the data reported after 1998 are presented; the references to earlier works are made only in the historical aspect. New data on the structure of pectin substances, their physiological activity, their role in plants, and their valuable physical properties are surveyed.

Overload of the cardiac left ventricle causes opposite local changes in repolarization duration (activation-recovery intervals) on the right- and left-ventricular epicardium, which depend on the duration of overload. The activation-recovery intervals on the right-ventricular lateral surface decrease after 1-min overload, but increase after 10-min overload. The length of activation-recovery intervals on the lateral surface of the left-ventricular apex increases after 10-min aortic stenosis more markedly in comparison with that after 1-min overload. Decrease/increase of local lengths of activation-recovery intervals results in modification of the general sequence of cardiac ventricular surface repolarization.

The duration of ventricular myocardium excitation increases during atrioventricular stimulation of dog heart and the sequence of depolarization of the right and left ventricles is desynchronized. Significant shortening of the activation-recovery interval in the intramural and subendocardial layers of the left ventricular base leads to modification of the repolarization sequence in this area and to an increase of total dispersion of activation-recovery intervals in the cardiac ventricles, as a result of which repolarization sequence starts partially repeating the depolarization sequence.

The sequence of ventricular epicardium repolarization in rabbits with hypokalemia is directed from the apex of the heart to its base in accordance with distribution of local repolarization intervals. Under conditions of hyperkalemia, the propagation of excitation wave is inhibited without changes in its sequence; while the duration of repolarization decrease mainly in zones where it was initially long (the base of the right ventricle), as a result of which the distribution of local repolarization intervals becomes more uniform and a relationship between the repolarization and activation sequences is formed.

Sodium salicylate (NaSA) increased induction of both intracellular and extracellular beta-1,3-glucanases in calluses of campion and duckweed. NaSA concentrations from 30 to 100 mM were optimal for induction of intracellular glucanase in the campion callus, and for induction of extracellular glucanase the optimal concentration varied from 5 to 100 mM. The glucanase activity in the duckweed callus was lower than in the campion callus, and co-cultivation of the campion callus with Trichoderma harzianum mycelium increased the production of intracellular and extracellular beta-1,3-glucanases and polygalacturonase in the callus. Biosynthesis by T. harzianum of glucanases, extracellular polygalacturonase and xylanase, and of intracellular galactosidase was increased. The co-cultivation was accompanied by increased activity of intracellular acidic isoform of glucanase Glu-3 secreted by the callus cells into the medium, whereas NaSA activated in the callus culture the extracellular acidic isoform Glu-1 and extracellular basic isoform Glu-5. These data indicate the induction of these isoforms and the specificity of protective response of plant cells to different factors.

A new effective and available method is proposed for preservation of human blood leukocytes at supercooling temperature (-10 degrees C). The method consists in induction of cold hypobiosis under protection of an original antifreeze protecting solution containing glycerol (cryoprotector), mexidol (antioxidant and membrane stabilizer), and gelatin preparation (modegel or gelatinol) as the solvent. No washing of the solution from the biological object before its intravenous injection is needed; the solution preserves morphological integrity of cells and their functional activity at a high level for 12 days.

We propose a new effective, available, and economic method for preservation of leukocytes at near-zero temperatures for 6 days using an original protecting solution.

Silenan, a pectin polysaccharide from common catchfly (Silene vulgaris), corrects disorders in the conduction of action potentials between cells of the sinoatrial area of frog heart forming a functional syncytium. Recovery of action potential conduction in the sinoatrial cells was recorded in long-term experiments (>8 h). The effect of silenan manifested mainly against the background of arrhythmic generation and impaired propagation of action potentials.