Multiple sclerosis (MS) is among the most common diseases of the central nervous system. The disease leads to pathological demyelination of axons in the white matter of the brain, followed by demyelination of gray matter, and is accompanied by progressive neurodegeneration in patients. The etiology of the disease is not fully understood. However, a number of external and internal factors that increase the likelihood of MS among the active capable part of the population have been established. The characteristics of age patients exacerbating the course of MS have been identified. The review discusses the mechanism of inflammation activation at MS involving NLRP3 inflammasome and neutrophils identified in recent years, the effect of inflammation on damage to the blood-brain barrier and MS progression, as well as reactive oxygen species-mediated participation of mitochondria in MS pathology development.

Pannexin 1 is a protein capable of forming channels for the release of ATP from animal cells. In small arteries, it regulates the contraction of smooth muscle cells, due to a functional connection with α_1D-adrenoceptors. Veins differ from arteries in structure and mechanisms of regulation of contraction, but the functions of pannexin in the venous bed have been poorly studied. The purpose of this study was to investigate the involvement of pannexin 1 in regulating the rhythmic contractile activity of the longitudinal smooth muscle layer in the mouse portal vein. The contractions of longitudinal vein preparations obtained from mice with global knockout of pannexin 1 gene and from С57Bl/6J mice (wild type) were studied in isometric mode. Venous preparations from both groups of mice demonstrated spontaneous rhythmic activity but the frequency of contractions in pannexin 1 knockout mice was higher than in wild-type mice. The α1-adrenoceptor agonists phenylephrine and methoxamine stimulated venous contractions. In the knockout group, the effect of phenylephrine, which has a higher affinity for α_1D-adrenoceptors, was lower, while the effect of methoxamine did not differ between groups. Evoking an increase in the frequency of vein contractions, exogenous ATP also demonstrated a less pronounced effect in pannexin 1 knockout mice compared to wild-type mice. While in wild-type mice, the change in the frequency of vein contractions induced by phenylephrine and ATP (but not methoxamine) inversely correlated with the baseline frequency of contractions, such dependence was not observed in knockout mice. In the presence of apyrase, which degrades extracellular ATP, the effect of phenylephrine on venous contraction frequency became less pronounced in wild-type mice but remained unchanged in knockout mice. Thus, in the mouse portal vein, pannexin does not directly participate in the generation of myogenic rhythmic activity but may regulate it. The obtained results suggest that in the longitudinal smooth muscle layer of the mouse portal vein, pannexin 1 channels serve as the main pathway for ATP secretion, and they are functionally associated with α1-adrenоceptors.

Structural aspects of host-parasite interactions between Triaenophorus nodulosus – European perch have been studied. A number of structural mechanisms involved in defense reaction against host immunity were revealed. Plerocercoids were located inside the perch liver. As a response to the invasion, a parasitic granuloma develops around the parasite. The capsule wall was shown to consist of several layers of different tissue types. The outer fibrous layer contained fibroblasts and connective tissue fibres. The inner layer was composed of several rows of flattened epithelioid cells connected with each other by desmosomes. On the inner surface of the capsule wall, individual macrophages were found showing phagocytic activity. The observed structural differences of the capsule wall cells depend on invasion time and physiologic condition of the interactions. Phagocytosis of apical parts of microtriches by macrophages was first documented. Additionally, radial fibrous non-cellular structures of unknown origin were observed. The plerocercoid lying free in the capsule cavity possessed developed hooks covered by the tegument, in contrast to adult worms with uncovered hooks. The tegument releases a thick layer of filamentous matrix, extracellular vesicles, and vacuolized microtriches. Free terminals of different specialized cell types were found to release secretory products via three pathways: frontal glands, tumuli, neurosecretory cup-shaped terminals. Universal adaptations intrinsic to all developmental stages, and those characteristic of plerocercoids (e.g. vacuolized microtriches) were revealed.

The number and functional structure of streptomycetes complexes isolated from the rhizosphere of three species of рlantae medicinales from the Vyatka-Kama Urals (Kirov region) – Melissa officinalis L., Urtica dioica L. and Capsella bursa-pastoris L. investigated. The total number of representatives of the genus Streptomyces varied in the rhizosphere from (3.0±1.6) × 10⁵ to (1.4±0.5) × 10⁶ CFU/g of substrate, depending on the type of plant, the proportion in the prokaryotic complex of different species varied from 4% (C. bursa-pastoris) to 31% (M. officinalis). Using selective treatment, 36 strains of bacteria were isolated, the cultural and morphological features of which are characteristic of representatives of the genus Streptomyces. It was found that the majority (82%) of isolates from the rhizosphere of M. officinalis are capable of synthesizing water-soluble metabolites of antifungal action with moderate and high activity. In the rhizosphere of C. bursa-pastoris, 42% of the isolates are able to effectively carry out enzymatic hydrolysis of cellulose. The strains isolated from the roots of U. dioica stood out among others with the most pronounced phytostimulating effect. Based on the results of the evaluation of the antagonistic, cellulolytic and phytoregulatory properties of streptomycetes, nine promising strains capable of synthesizing indole compounds (indolyl-3-acetic acid) in an amount of up to 24.0±0.9 µg/ml and a radial growth rate of up to 65.7±8.8 µm/h were selected, which can have a positive effect on the growth and development of agricultural plants. The results obtained will be useable for determining strategies for the search, identification and use of this group of bacteria as biological control agents and plant growth stimulators.

Natural or artificial separation of a water body from its parent water area leads to stratification of its water column and the development of a vertical sequence of planktonic communities. Data on succession of algal communities are sparse. Seasonal variability in the composition and abundance of microalgae in different water layers of the semi-enclosed lagoon “Lake Kislo-Sladkoe” in 2021 was studied during stable stratification and bottom anoxia. Species composition and carbon biomass at different depths, as well as the integrated phytoplankton biomass in the water column, were determined. An analysis of the similarity of the phytoplankton structure in different water layers was carried out. 53 species and/or genera with a predominance of marine forms and 11 higher rank taxa were identified. During the ice-covered period, most of the water column was anaerobic, and the freshwater cyanobacterium Microcystis ichthyoblabe dominated under the ice. After ice thaw, the biomass maximum shifted towards the boundary of sulfide zone (into the chemocline). In May–early June, the highest biomass was determined by green alga Chlamydomonas sp., in June-July by the diatom Cyclotella choctawhatcheeana. Type of nutrition changed from predominantly autotrophic at the beginning of the season (March–July) to predominantly heterotrophic (August–October). The highest biomass values were recorded in July– September (149.8 mg С/m²) due to the dominance of the predatory dinoflagellate Oxyrrhis marina. A comparison was made with water bodies of a similar type.

Warming trends in high latitudes will lead to changes in the thermo-hydrological regime of permafrost soils, affecting the structure and functioning of northern ecosystems. The study of radial tree growth response to current environmental conditions is commonly used to understand the future reaction of trees. This study evaluates the response of four Cajander larch (Larix cajanderi Mayr) sites in the continuous permafrost region to different environmental conditions in Northern and Central Yakutia (Republic of Sakha). Correlation coefficients between tree-ring width indexes and climate parameters were calculated over the 1966–2021 period. The results showed that air temperature is the main factor limiting the radial tree growth in all the sites (mainly June temperature; r = 0,38–0,41; p < 0,01). However, the timing and intensity of the temperature sensitivity increases with the latitude. The most sensitive to climate woody plants grow in the northern part of the study region where growing season is rather short. Running correlations showed a general decreasing trend in intensity of the temperature response in radial growth chronologies. Probably it is linked to the increase in summer temperatures in recent decades, thus highlighting the ecological plasticity of the larch trees. These results can help to assess changes in the productivity of the forest ecosystems in particular regions of boreal zone.

Dendrochronological assessments were conducted on larch samples across three sites within the Tabaga region (central part of Yakutia, Russia), resulting in the creation of a tree-ring width database. The plots are characterized as larch-birch lingonberry-forb forest type. More than 20 samples were collected from each plot – 73 cores. The methodology involved the selection of “reference years” – years in which the majority of trees demonstrated the narrowest or widest growth rings. A correlation between the width of larch tree rings and the Selyaninov hydrothermal coefficient was identified. Analysis of the comprehensive statistical data set from site T3 established a relationship between the hydrothermal conditions in Central Yakutia during August and the radial growth of larch trees over the period of 1920–2018. It is hypothesized that there is a latitudinal dependency of radial growth on hydrothermal conditions among larch trees in the Northern Hemisphere, in light of climate change and other geophysical factors.

Recently, there has been increasing evidence in favor of prenatal programming influence on the development of many diseases in adults, including cardiovascular pathologies. However, the mechanisms underlying the programming effect of developing cardiovascular dysfunction remain unclear, which prevents timely diagnosis and identification of potential clinical therapy. The aim of this study was to evaluate the effects of acute hypoxia during early organogenesis on heart rhythm formation and its regulation in early postnatal development in rats. It was shown that acute hypoxia suffered by rat pups on the 10^th day of intrauterine development did not change the overall dynamics of heart rhythm formation in the first month of postnatal period. However, the experimental animals showed lower heart rate compared to control in the first weeks of life in addition to higher values of rhythm variability and the RMSSD index (root mean square of successive differences in R-R intervals) indicating an expressed tone of parasympathetic division of the ANS. Moreover in the first week of life the basic heart rate following pharmacological blockade of sympathetic and parasympathetic cardiotropic nervous influences in rats suffered from prenatal hypoxia turned out to be 15% higher than in control animals, supposing prenatal hypoxia influence on heart rhythm formation due to intracardiac mechanisms.