[The study of mineral composition and structure of uroliths in the residents of Tomsk district (Tomsk)]

AIM

To successfully treat and prevent urolithiasis, the composition and structure of uroliths should be examined using modern analytical techniques. For a long time, studies of the biomineral formation in the human body have been conducted exclusively in the field of medicine. The main attention has been paid to the diagnosis and treatment of diseases leading to the occurrence of pathogenic formations. At the same time, it is quite obvious that it is important to have a clear idea about the causes of pathogenic formations, the mechanisms for their further formation, composition and structure. Currently, these issues are widely studied all over the world by mineralogists, biochemists, geo-ecologists using methods of mineralogical analysis. The aim of this work was to determine the content of the elements that make up uroliths. This value should be normalized by the clarks of the noosphere. Studies on the mineral composition and structure of uroliths in the Tomsk region allowed to calculate the content of elements. It turned out that each medical district has its own specific geochemical series, which depends, probably, on natural and technogenic factors.

MATERIALS AND METHODS

The study included urolith samples obtained from residents of 4 medical sub-districts of Tomsk district. 100 samples of different mineral composition were studied. Analytical techniques including crystal-morphological, spectral, X-ray structural, instrumental neutron-activation, electron microscopic analyses were used to investigate the morphology, mineral composition and structure of uroliths.

RESULTS

The average content of elements in the uroliths, and the element concentrations normalized by the clark were established. After calculating the concentration, geochemical associative series of elements were formed. Depending on the morphology, drusiform, microspherolite, porous, coral formations, uroliths with a smoothed surface and stones with combined morphology were identified. Three groups of uroliths were defined according to their structural features: crystalline-granular, spherolithic and combined.

CONCLUSION

Studies to determine the mineral composition and structure of the uroliths of the inhabitants of the Tomsk region made it possible to calculate the content of the elements that make up uroliths, normalized by clarks of the noosphere. Each medical sub-district has its own specific geochemical series, which depends on natural and technogenic factors. The increased value of the indicator of the content of elements in uroliths should serve as a warning factor for developing measures to reduce the urolithiasis incidence in the population.

[Microbial metabolism of the carbon and sulfur cycles in Shira Lake (Khakasia)]

Microbiological and biogeochemical studies of the meromictic saline Lake Shira (Khakasia) were conducted. In the upper part of the hydrogen-sulfide zone, at a depth of 13.5-14 m, there was a pale pink layer of water due to the development of purple bacteria (6 x 10(5) cells/ml), which were assigned by their morphological and spectral characteristics to Lamprocystis purpureus (formerly Amoebobacter purpurea). In August, the production of organic matter (OM) in Lake Shira was estimated to be 943 mg C/(m2 day). The contribution of anoxygenic photosynthesis was insignificant (about 7% of the total OM production). The share of bacterial chemosynthesis was still less (no more than 2%). In the anaerobic zone, the community of sulfate-reducing bacteria played a decisive role in the terminal decomposition of OM. The maximal rates of sulfate reduction were observed in the near-bottom water (114 micrograms S/(1 day)) and in the surface layer of bottom sediments (901 micrograms S/(dm3 day)). The daily expenditure of Corg for sulfate reduction was 73% of Corg formed daily in the processes of oxygenic and anoxygenic photosynthesis and bacterial chemosynthesis. The profile of methane distribution in the water column and bottom sediments was typical of meromictic reservoirs. The methane content in the water column increased beginning with the thermocline (7-8 m), and reached maximum values in the near-bottom water (17 microliters/l). In bottom sediments, the greatest methane concentrations (57 microliters/l) were observed in the surface layer (0-3 cm). The integral rate of methane formation in the water column and bottom sediments was almost an order of magnitude higher than the rate of its oxidation by aerobic and anaerobic methanotrophic microorganisms.