Explore the vast range of titles available.

The response to stress involves the activation of pathways leading either to protection from the stress origin, eventually resulting in development of stress resistance, or activation of the rapid death of the organism. Here we hypothesize that mitochondrial reactive oxygen species (mtROS) play a key role in stress-induced programmed death of the organism, which we called “phenoptosis” in 1997. We demonstrate that the synthetic mitochondria-targeted antioxidant SkQ1 (which specifically abolishes mtROS) prevents rapid death of mice caused by four mechanistically very different shocks: (a) bacterial lipopolysaccharide (LPS) shock, (b) shock in response to intravenous mitochondrial injection, (c) cold shock, and (d) toxic shock caused by the penetrating cation C 12 TPP. Importantly, under all these stresses mortality was associated with a strong elevation of the levels of pro-inflammatory cytokines and administration of SkQ1 was able to switch off the cytokine storms. Since the main effect of SkQ1 is the neutralization of mtROS, this study provides evidence for the role of mtROS in the activation of innate immune responses mediating stress-induced death of the organism. We propose that SkQ1 may be used clinically to support patients in critical conditions, such as septic shock, extensive trauma, cooling, and severe infection by bacteria or viruses.

The methodics background for the nondestructive element concentration diagnostics of cylindric shape material objects surface layer is developed. The diagnostics is produced without objects form-factor distortion on base of ion beams and X-ray analytical methods. The depth element concentration distribution determination found on the ion beams Rutherford backscattering data and results of X-ray fluorescence testing in conditions of TXRF modified measurements. Possibilities of the elaborated analytical conception are illustrated by experimental data obtained at study of element content in surface layer of the nuclear heat release cell shell.

The article is concerned with peculiarities study of the quasimonochromatic optical fluxes propagation through thin planar transparent layer of multilayer coating. There is shown that these fluxes can be transported by the layer in process of its multiple consequtive total internal reflection or by the waveguide-resonance propagation manner depending on correlation between the layer width and the radiation coherence length half of transported fluxes. Efficiency comparison of these radiation transportation mechanisms showed that the waveguide-resonance propagation approach is more adequate for results description of the optical waveguides functioning. It allowed to conclude that optical waveguides (fibers) function in frame of the waveguide-resonance paradigm and the waveguide-resonance mechanism is responsible for the light fluxes transportation on great distances.

Wildfires considerably affect forest ecosystems. However, there is a lack of data on the post-fire status of insect communities in these ecosystems. This paper presents results of a study conducted in 2019 which considered the post-fire status of the insect fauna in a Protected Area, Mordovia State Nature Reserve (Republic of Mordovia, centre of European Russia), considered as regional hotspot of insect diversity in Mordovia. We sampled insects on intact (unburned, control) and fire-damaged (burnt in 2010) sites and compared the alpha-diversity between sites. In total, we sampled and analysed 16,861 specimens belonging to 11 insect orders, 51 families and 190 species. The largest orders represented in the samples were Coleoptera (95 species), Diptera (54 species), Hymenoptera (21 species), and Neuroptera (11 species). Other insect orders were represented by between one and four species. The largest four orders (Coleoptera, Lepidoptera, Diptera and Hymenoptera) represented 96.7% of all studied specimens. We found that in the ninth year after low intensity surface fire damage, the insect diversity had returned to a similar level to that of the control (unburned) sites. Sites damaged by crown wildfire differed considerably from other sites in terms of a negative impact on both species diversity and the number of specimens. This indicates the serious effect of the crown fires on the biodiversity and consequent long-term recovery of the damaged ecosystem.

We studied the effect of Refralon on the electrophysiological properties of the supraventricular myocardium against the background of adrenergic (epinephrine) influence in the zone of the pulmonary veins, the area where 50-90% of atrial arrhythmias is triggered. The experiments were carried out on isolated tissue preparations of Wistar rats. The multichannel microelectrode array technique was used to record action potentials simultaneously in the atrium and in the ostium and distal parts of the pulmonary veins. Epinephrine application (12-50 nM) led to depolarization of the resting potential and the conduction block in the distal part of the pulmonary veins. Refralon (30 μg/kg) restored the resting potential in the distal part of the pulmonary veins. Against the background of epinephrine, Refralon did not significantly change the duration of the action potential at 90% repolarization in comparison with control. At the same time, the comparison drug E-4031 against the background of epinephrine significantly increased the duration of action potential in the atrium and in the ostium of the pulmonary veins, and sotalol increased it only in the ostium. Neither E-4031, nor sotalol restored conduction in their distal part. Refralon has a biphasic effect under conditions of adrenergic stimulation: the fast component is responsible for stabilizing the resting potential in the pulmonary vein and reduces the dispersion of action potential duration in the atrium and pulmonary vein and is also quickly washed away, and the slow component is responsible for the increase of the action potential duration and is slowly washed away.

Studies on the vertical distribution of arthropods in temperate forests have revealed the uneven vertical distribution of communities. Many factors influence these patterns simultaneously. However, there are still many questions related to the vertical distribution of Coleoptera in deciduous forests of the temperate zone. The research was carried out within the territory of the Republic of Mordovia (the center of the European part of Russia). Fermental traps with a bait made of fermenting beer with sugar were used to collect Coleoptera. The collections were carried out from May to September 2020 at five sites in a deciduous forest. We set traps at a height of 1.5, 3.5, 7.5 and 12 m above the ground) on the branches of trees. Ninety-two species were identified at the end of studies at different heights. The families Nitidulidae (15 species), Cerambycidae (14 species), Elateridae (7 species), Curculionidae (7 species) and Scarabaeidae (7 species) had the greatest species diversity. The greatest species diversity was recorded at a height of 1.5 m, while the smallest one was recorded at a height of 7.5 m. The minimum number of specimens was recorded at a height of 12 m. The largest differences in the Jaccard similarity index were obtained between samples from a height of 1.5 and 12 m. The Shannon’s diversity index was higher near the ground than in the tree crowns (at heights of 7.5 and 12 m), and the Simpson index had the opposite tendency. Glischrochilus hortensis and to a lesser extent Cychramus luteus preferred to live in the lowest layers of deciduous forest (1.5 m). Cryptarcha strigata was mainly found with relatively high numbers at heights of 3.5 m and 7.5 m. The abundance and occurrence of Protaetia marmorata and Quedius dilatatus were higher in the uppermost layers of the crowns. The number of saproxylic beetle species at heights of 3.5–12 m was almost the same, while in the surface layer it decreased. The number of anthophilic beetle species was also lower at a low altitude. Our data confirm the relevance of sampling in forest ecosystems at different altitudes while studying arthropod biodiversity.

— The work presents short characteristics of the X-ray fluxes waveguide-resonance propagation phenomenon. There is described peculiarities of the X-ray nanophotonics base device functioned in frame of the phenomenon – the planar X-ray waveguide-resonator and denoted directions of its development. X-ray waveguide-resonance devices elaboration in the process of base construction modification are discussed.

— The work presents short descriptions of ion beam methods and X-ray diagnostics in conditions of the total external reflection geometry with accent on the planar nanostructures peculiarities study. These objects specificity is described, and these are formulated tasks, which are more suitable for these method applications. Experimental results, which confirm the high efficiency of real objects investigation by these methods are discussed. Possible directions of ion beam analysis and X-ray methodical background on base of the planar X-ray waveguide-resonators application are pointed. The profit from its devises use is re-ndered.

Background Domestication and centuries of selective breeding have changed genomes of sheep breeds to respond to environmental challenges and human needs. The genomes of local breeds, therefore, are valuable sources of genomic variants to be used to understand mechanisms of response to adaptation and artificial selection. As a step toward this we performed a high-density genotyping and comprehensive scans for signatures of selection in the genomes from 15 local sheep breeds reared across Russia. Results Results demonstrated that the genomes of Russian sheep breeds contain multiple regions under putative selection. More than 50% of these regions matched with intervals identified in previous scans for selective sweeps in sheep genomes. These regions contain well-known candidate genes related to morphology, adaptation, and domestication (e.g., KITLG, KIT, MITF, and MC1R ), wool quality and quantity (e.g., DSG@ , DSC@ , and KRT@ ), growth and feed intake (e.g., HOXA@, HOXC@, LCORL, NCAPG, LAP3, and CCSER1 ), reproduction (e.g., CMTM6, HTRA1, GNAQ, UBQLN1, and IFT88 ), and milk-related traits (e.g., ABCG2, SPP1, ACSS1, and ACSS2 ). In addition, multiple genes that are putatively related to environmental adaptations were top-ranked in selected intervals (e.g., EGFR, HSPH1, NMUR1 , EDNRB , PRL, TSHR, and ADAMTS5 ). Moreover, we observed that multiple key genes involved in human hereditary sensory and autonomic neuropathies, and genetic disorders accompanied with an inability to feel pain and environmental temperatures, were top-ranked in multiple or individual sheep breeds from Russia pointing to a possible mechanism of adaptation to harsh climatic conditions. Conclusions Our work represents the first comprehensive scan for signatures of selection in genomes of local sheep breeds from the Russian Federation of both European and Asian origins. We confirmed that the genomes of Russian sheep contain previously identified signatures of selection, demonstrating the robustness of our integrative approach. Multiple novel signatures of selection were found near genes which could be related to adaptation to the harsh environments of Russia. Our study forms a basis for future work on using Russian sheep genomes to spot specific genetic variants or haplotypes to be used in efforts on developing next-generation highly productive breeds, better suited to diverse Eurasian environments.

Working memory represents the ability of the brain to hold externally or internally driven information for relatively short periods of time 1 , 2 . Persistent neuronal activity is the elementary process underlying working memory but its cellular basis remains unknown. The most widely accepted hypothesis is that persistent activity is based on synaptic reverberations in recurrent circuits. The entorhinal cortex in the parahippocampal region is crucially involved in the acquisition, consolidation and retrieval of long-term memory traces for which working memory operations are essential 2 . Here we show that individual neurons from layer V of the entorhinal cortex—which link the hippocampus to extensive cortical regions 3 —respond to consecutive stimuli with graded changes in firing frequency that remain stable after each stimulus presentation. In addition, the sustained levels of firing frequency can be either increased or decreased in an input-specific manner. This firing behaviour displays robustness to distractors; it is linked to cholinergic muscarinic receptor activation, and relies on activity-dependent changes of a Ca 2+ -sensitive cationic current. Such an intrinsic neuronal ability to generate graded persistent activity constitutes an elementary mechanism for working memory.