Vesicles obtained from pericardial fluid, cerebrospinal fluid, urine, and saliva by differential centrifugation were examined using low-voltage scanning electron microscopy. Numerous particles and their aggregates were found in the obtained micrographs. The size of most individual particles ranged from 25 to 150 nm, which approximately corresponds to the size of extracellular vesicles. Thus, low-voltage scanning electron microscopy enables the acquisition of high-quality images of both single extracellular vesicles and their aggregates.

Within the WHO framework of genomic epidemiological surveillance of tuberculosis, we have developed a panel of primers and TaqMan probes for PCR-based identification of SNPs in major epidemiological genotypes of Mycobacterium tuberculosis responsible for the spread of MDR/XDR strains in North Eurasia. Validation was performed on a dataset of 590 randomly selected strains circulating in the Krasnoyarsk Krai and Irkutsk region in 2021-2025. We identified 308 and 164 Beijing (L2) strains in the Krasnoyarsk and Irkutsk regions, respectively. The identified Beijing (L2) genotypes included B0/W148 (19 and 76); Central Asian (85 and 47) and its Central Asian Outbreak subtype (12 and 25); and orphan L2 genotypes (14 and 16). We also revealed 88 and 30 Euro-American (L4) strains in the Krasnoyarsk Krai and Irkutsk region, respectively. The identified L4 genotypes included Haarlem (9 and 6); LAM (35 and 7); Ural (19 and 5); S (2 and 0); and orphan L4 genotypes (15 and 12). We developed an approach employing two PCR to discriminate the principal M. tuberculosis genotype set into L2 and L4 lineages covering over 99% of all tuberculosis strains circulating in Russian Federation and other North Eurasian countries. Within the proposed framework, the required and sufficient number of PCR for genotyping and in-depth subtyping does not exceed eight. The feasibility of developing tests for further subtyping of epidemiological M. tuberculosis genotypes is discussed.

The aim of the study was to evaluate the biological activity of a new type of cardioprotectors, activators of Nrf2, based on pyridoxine and fumaric acid derivatives in vitro and in vivo. It was found that di(3-hydroxy-4,5-bis(hydroxymethyl)-2-methylpyridinium) fumarate is an effective activator of Nrf2 transcription factor and exhibits cytoprotective and antioxidant activity in vitro on a cardiomyocyte model. In addition, this compound reduces the cardiotoxic effect of doxorubicin in vivo by suppressing the development of oxidative processes and activating the Nrf2-dependent antioxidant response in the heart. The studied pyridoxine and fumaric acid derivative has high potential as a candidate medication for reducing the side effects of anthracycline antibiotics, as well as for protecting heart cells in various cardiovascular diseases and age-related changes. The revealed effects are of great importance for the development of approaches to designing a new type of cardioprotective compounds, activators of the transcription factor Nrf2.

We evaluated the association of alleles of human leukocyte antigen (HLA) class II genes and the levels of secretion of IL-4 and IFNγ in the blood of individuals vaccinated/revaccinated with a live plague vaccine and living in the Gorno-Altai high-mountain and Tuvinian mountain natural plague foci. Significant differences were identified in the blood content of IL-4 and IFNγ in volunteers with different variants of alleles in the HLA-DRB1, HLA-DQA1, and HLA-DQB1 loci, which indicates a substantial influence of their polymorphism on the immunological reactivity during specific plague prevention. Further research within the framework of immunological monitoring of the population living in plague-endemic territories will allow identifying the features of the influence of polymorphism of HLA class II genes on the formation of post-vaccination anti-plague immunity in humans.

This study explores a possible therapy for managing atherosclerosis through macrophage modulation induced by CXCL4 receptor activity. Three herbal compounds potentially blocking the CXCL4 receptor, i.e., amygdalin, 6-shogaol, and resveratrol, were tested in silico and in vitro. In silico analysis revealed the highest binding affinity of amygdalin to the CXCL4 receptor. Flow cytometry of peripheral blood mononuclear cells from 11 healthy subjects showed CD36 expression in groups treated with amygdalin, which attested to macrophage differentiation and maturation. ELISA showed increasing TNF-α production associated with enhanced cell phagocytosis, while MMP7 expression decreased, indicating lower molecular adhesion capability. Thus, amygdalin can potentially prevent M4 macrophage development, which plays a role in atherosclerotic plaque instability, though further validation is needed.

The removal of the cuticular membrane (chorion) in developing Danio rerio embryos was used as a model of mild and long-acting influences to study their consequences for adult D. rerio. We studied the effect of dechorionation 12 h after fertilization on survival, body weight, sex ratio, behavior in the home tank and in the novel tank test, the level of serotonin (5-HT), dopamine (DA), norepinephrine (NE), and their metabolites 5-hydroxyindoleacetic (5-HIAA) and 3,4-dihydroxyphenylalanine acetic (DOPAC) acids in the brain of 6-month-old fish. Dechorionation did not affect survival, body weight, sex ratio, and locomotor activity of adult fish. At the same time, it significantly affected vertical activity of adult fish: the time spent in the upper third of the tank increased in a familiar environment (in a school and in a home tank), but decreased under stressful conditions (novel tank test). Dechorionation did not affect the levels of DA, DOPAC, 5-HT, 5-HIAA, the DOPAC/DA ratio and 5-HIAA/5-HT, but significantly decreased the level of NE in the brain of adult fish. Thus, we have demonstrated the critical role of the chorion for tuning of the brain NE system and the formation of defensive behavior in adult D. rerio: dechorionation causes long-term changes in the brain NE system and in the defensive behavior in the novel tank test in adult fish.

Hydrogel cell therapy is a promising area of treatment for spinal cord cysts. The results of the development of a product based on fibrin gel with olfactory ensheathing cells are presented. It has been shown that transplantation of cells in the gel to rats with experimental contusion injury of the spinal cord has a positive effect on the locomotor activity of animals and morphometric parameters of the cyst. Fibrin gel can act as a carrier of olfactory ensheathing cells during transplantation into a spinal cord cyst.

We studied the effect of peat smoke intoxication in pregnant rats on the early postnatal development of the second-generation offspring. The smoke was inhaled on days 14-18 of pregnancy. The first-generation offspring at puberty (3 months) was mated to produce the second-generation offspring in the following 3 variants: females exposed to prenatal smoke and intact males (experiment 1), males exposed to prenatal smoke and intact females (experiment 2), and males and females exposed to prenatal smoke (experiment 3); intact females and males comprised the control group. In the second-generation offspring, physical development, body weight gain dynamics, rate of maturation of sensorimotor reflexes, and parameters of open-field behavior were assessed. The results showed that exposure to peat smoke in pregnant rats reduced survival rates and impaired physical development in the second-generation offspring.

The effectiveness of ELISA in combination with multivariate discriminant analysis (MDA) for differentiating late latent syphilis (LLS) and false positive reactions (FPR) for syphilis was assessed. ELISA was used to determine IgG levels in the sera of patients with confirmed LLS and FPR to five recombinant Treponema pallidum antigens: Tp319, Tp453, Tp684, Tp965, and Tp1038. The three most informative antigens Tp0453, Tp0684, and Tp1038 were identified by using stepwise discriminant analysis, and a discriminant function was constructed to distinguish the patient groups with LLS and FPR. The accuracy of differentiating the two nosologies was 90.3%. The Tp0684 antigen was the most substantial differentiating factor. The results demonstrate the promise of using a combination of ELISA and MDA to improve the diagnosis of latent forms of syphilis and reduce the frequency of erroneous interpretations of the serological tests.