The Bank of Biological Samples by Seversk Biophysical Research Center

Purpose: Description of the collection, structure and development dynamics during the period from 2015 to 2019 of the biological material bank of the Seversk Biophysical Research Center, as well as research works carried out using biological material from its collection. Material and methods: The collection of bank of biological material includes the following types of biological material: venous blood, genomic DNA of white blood cells, cytogenetic suspensions of blood lymphocytes, surgical, biopsy and autopsy material. Biological material was obtained from people exposed to chronic radiation exposure: employees of the nuclear industry and the population permanently residing in the territory located in the area of the nuclear industry. Results: At present, the collection of the biological material bank contains more than 21,000 samples of biological material obtained from more than 8,000 donors. The collection of bank of biological material is represented by 4 main blocks: biological material of conditionally healthy employees of company of the nuclear industry (Siberian Chemical Combine); biological material of conditionally healthy people permanently residing in the territory located in the area of the nuclear industry enterprise (Seversk); biological material of patients (workers of the Siberian Chemical Combine and residents of Seversk) with malignant neoplasms and biological material of patients (workers of the Siberian Chemical Combine and residents of Seversk) with acute myocardial infarction. In the collection of bank of biological material, the proportion of samples of biological material of relatively healthy workers of the Siberian Chemical Combine is 33 %, residents of Seversk — 40.8 %, patients with malignant neoplasms — 22.2 %, patients with acute myocardial infarction — 4 %. Conclusion: Biological material bank Seversk Biophysical Research Center is unique collection of biological material samples of healthy people and patients with socially significant diseases. A feature of the biological material of the biological material bank is that it is obtained from people who have been exposed to chronic low-intensity radiation exposure and can be used to evaluate its radiogenic effects.

GAS-GYPSUM MATERIALS PROPERTIES MODIFIED BY PLASTICIZING AGENTS

The paper deals with porous gypsum building materials having heat-insulating properties and applied in low-rise building construction, in the manufacture of flat and room dividers.Anhydrite of the Siberian Chemical Combine together with sodium carbonate is used as a gas-forming component. To regulate the plasticity of the mortar mixture, the Steinberg MP-4 and Steinberg PR-1S(A) superplasticizers are introduced into the composition, and their effect on the porous gypsum mixture properties is studied.The analysis of the superplasticizer influence on the properties shows that the use of the Steinberg MP-4 with the amount of 2 wt.% of gypsum is optimum to achieve high strength of up to 27 MPa, while providing high mobility of the porous mixture. The main role of superplasticizers in a gypsum water-soluble composition is to increase the ξ-potential of the material and to reduce the water-gypsum ratio of the mixture while maintaining its mobility. The effect of superplasticizers largely depends on the initial modification of the binder, its dispersibility and mobility.

EXPANSION OF CYTOGENETICALLY MODIFIED FORM OF OPISTHORCHIS FELINEUS IN THE TOM RIVER BASIN

In 1993, karyotyping of Opisthorchis felineus sporocysts, isolated from aquatic mollusks Bithynia inflat a in the industrial wastewater of the Siberian Chemical Combine discovered cytogenetically modified 12-chromosome specimens. In 2012-2013, a repeated study of the spread of these mutant trematodes in the lower course of the river Tom was carried out. It was established that specimens with sporocysts of O. felineus having 2n=12 were found in 8 of 10 places of catching. The caught goldfish were used to isolate metacercariae to infest golden hamsters in the experimental conditions. After 5 months, the hamster livers were processed to extract marita specimens and the number of chromosomes in their ovaries and testes was cytogenetically determined. The results of analysis of the spread of O. felineus carried out by this method showed the presence of 12-chromosome form of the Opisthorchis marita in all places of fishing out in the lower course of the river Tom. Analysis of the 12-chromosome karyotype allows to conclude that this mutation was a result of Robertsonian fusion of chromosomes 3 and 6 of 14-chromosome form of karyotype.