Kirill Avdeev

To perform the first concurrent characterization of gut and respiratory microbiome profiles in colorectal cancer patients from Western Siberia, Russia. We analyzed synchronous fecal and sputum samples from 40 treatment-naive colorectal cancer patients and 45 healthy controls using 16S rRNA gene (V3-V4) sequencing and QIIME 2-based bioinformatic workflows. While alpha-diversity indices did not differ significantly between groups, beta-diversity analysis revealed substantial compositional differences for both ecosystems. Colorectal cancer patients exhibited gut enrichment of Proteobacteria, Fusobacteria, Fusobacterium, Odoribacter, Lachnospiraceae_UCG-010, Erysipelatoclostridium, Parvimonas, Finegoldia, Clostridium and Bacteroides (Bacteroides fragilis), alongside sputum enrichment of phyla Bacteroidetes and Actinobacteria, as well as genera Neisseria, Prevotella, Lactobacillus, Rothia, Nocardia, Leptotrichia, Campylobacter, and Helicobacter. Stage-associated shifts included elevated Akkermansia in gut microbiomes of patients with advanced-stage disease and higher Campylobacter in early-stage sputum. These findings identify distinct gut–respiratory dysbiotic signatures in a previously understudied population. Our results underscore the potential of dual-compartment microbiome profiling for developing non-invasive biomarkers and require validation in larger, multicenter cohorts to elucidate mechanistic links between respiratory dysbiosis and colorectal carcinogenesis.

The study specifies the changes in radon activity concentration (RAC) in soil gas with depth and emphasizes the significance of the meteorological factor for deeper boreholes. Radon activity concentration was measured in 0.6 m, 1 m and 1.5 m boreholes, and the depth gradient was also calculated. Spatial patterns were estimated using an autocorrelation index. RAC ranged from 9454 ± 439 Bq/m³ for 0.6 m, 16,031 ± 602 Bq/m³ for 1 m and 22,049 ± 937 Bq/m³ for 1.5 m. RAC increased with depth at most of the study sites and behaved quite uniformly in spatial terms. At the same time, no significant differences in the activity of uranium (²³⁸U) series isotopes at different soil depths were detected. Significant spatial variability in radioactivity and the physical properties of soils is noted. The highest gradient was between 0.6 and 1 m. It was found that with increasing depth the connection between the RAC and the meteorological conditions (temperature and humidity) of the surface layer of the atmosphere is lost. It follows that for shallow boreholes it is necessary to consider the influence of meteorological conditions. RAC in 1 m boreholes correlates with 1.5 m and 0.6 m boreholes, but no correlation was found for the 1.5 m and 0.6 m boreholes themselves. Thus, 1 m boreholes are optimal for radon monitoring. A high level of RAC indicates a high potential for indoor radon exposure in this territory, with corresponding epidemiological consequences in the long term.

Geographic patterns determine geogenic radon factors that, changing over the territory, form spatial structures of different scales associated with regional and local variations. The study of these structures is important for assessing the possibility of using limited data to predict geogenic radon potential. Our research focuses on the study of the physical properties of soils (moisture, soil density, porosity and void ratio) in the Kuznetsk coal basin. Their variations are studied using statistical methods, a variogram cloud and spatial autocorrelation of data. Soil moisture and porosity have the greatest variability in space and with depth. We conclude that the assessment of geogenic radon predictors requires consideration of the variation coefficient and autocorrelation indices at different scales. Based on the variability of humidity and the fairly homogeneous nature of the studied soils (loams), to assess the radon hazard, it is necessary to study the influence of climatic conditions, since the permeability of the environment for radon will be determined by soil moisture. With the predominance of substantially clayey soils, it is necessary to study the content of ²²⁶Ra in the upper horizons, since it is assumed that radon is predominantly diffusely transferred, in which its role is dominant.

This study is aimed at elucidating the fractional composition, volume and toxicity of dust that is deposited in the snow cover for the period of snow accumulation at different distances from coal mines and a coal-fired power station in the Kemerovo region (Russia). During the filtration process, fractions of 10–0.1 µm and less than 0.1 µm were isolated and weighed. Light microscopy was used to estimate the size of dust particles in the 10–0.1 µm fraction. We found that the total volume and fractional composition of dust has no significant trend to change in the research space. The dust contamination is associated mainly with PM₂ particles. Genotoxic tests on cell lines A549 and MRC-5 with different concentrations of dust showed high toxicity (including control points). Taking into account the fact that an increase in the concentration of PM leads to intensification in the toxicity of dust, we can determine that the territory within the studied boundaries is dangerous for the population. Our study is important for understanding the processes of formation, toxicity, transport and sedimentation in the snow cover from dust generated in the process of coal mining and the operation of a coal-fired power station.