Биология

Characterization of the species composition of the dominant representatives of Protozoa in natural plague foci is important for the study of certain aspects of ecology and persistence mechanisms of Yersinia pestis. Determination of systematic belonging of amoebas isolated from the soils of the Gorno-Altai high-mountain plague focus in 2016 year was carried out by analyzing nucleotide sequences of ribosomal genes of these protozoans. The analyzed sequences of ribosomal genes were obtained by PCR with specific primers followed by sequencing of PCR products.

Many bacteria, in response to unfavourable environmental conditions, can synthesise polyesters of the polyhydroxyalkanoate (PHA) class. These biopolymers, accumulating intracellularly in the form of granules, help the bacteria to cope with negative environments and are utilised as reserve sources of carbon and energy. Rhizobacteria of the species Azospirillum brasilense synthesise a single type of PHA, poly-3-hydroxybutyrate (PHB), in response to stress factors.

Until this article in the Saratov Province special studies of fungivorous beetles fauna of Coleoptera was carried out. The collection material was conducted by the authors in the spring and summer of 2017 with fruiting bodies of different species of xylotrophic Basidiomycetes of the families Polyporaceae and Fomitopsidaceae on the territory of 4 districts of the Saratov Province (Voskresenskiy, Khvalynskiy, Saratovskiy, Engelskiy). As a result, on 4 species of xylotrophic fungi were found 13 species of Coleoptera from 6 families.

Oculomotor activity is a necessary component of the human mental processes, thanks to which the acquisition, transformation and use of visual information takes place. Therefore, by registering and analyzing eye movements, we are able to access the hidden (internal) forms of activity that occur extremely quickly and unconsciously. Thanks to the appearance in Russia of modern trainees, interest in the oculomotor theme has now increased significantly.

Microorganisms inhabiting saline environments can produce compounds unique in structure and properties. This ability recently prompted researchers to study the biotechnological potential of halophiles. This work aimed at screening the exopolysaccharideproducing halophilic and halotolerant microorganisms of two saline lakes, one in in Egypt and the other in Russia. For strain isolation and characterization, we used microbiological and physico-chemical methods, as well as light and transmission electron microscopy.

Traumatic brain injury (TBI) is a major health problem that causes long term neurological deficit in the majority of patients and does not have any clinically proved effective treatment. Transcranial direct current stimulation (tDCS) is an emerging electroceutical therapy suggested for TBI rehabilitation. However, optimal parameters of stimulation and mechanisms of action are not determined due to lack of preclinical studies, impeding its clinical implementation.

This work is devoted to the comparative analysis of the functional state of systemic hemodynamics in Russian and foreign students depending on the localization of the transition zone in the chest leads of ECG during the active orthostatic test. Having assessed physical development, we measured the parameters of arterial pressure and ECG using the module «Electrocardiogram» APK «Valenta». The prevalence of asthenic type of physique in foreign students against the deficiency of physical development determines the vertical position of the heart.

The object of the study was sprouts of durum wheat Triticum durum L. Cultivation was carried out at a temperature of 15 ± 1°C and 20 ± 2°C. To study the influence of the temperature factor on the development of the photosynthetic apparatus, the quantitative content of chlorophyll a, chlorophyll b, and carotenoids was determined. Some varieties, when subjected to a change in the temperature of cultivation, respond with a change in the indices determining their stress tolerance, namely the ratio of chlorophyll a and chlorophyll b, carotenoids and chlorophylls.

The article provides information about the epiphytic lichen flora of the Natural Park “Kumysnaya Polyana” (NP), which is located in Saratov. It is a regional SPNA (Special Protected Natural Area). The researches were conducted in forest communities of NP in 2011–2016. Standard techniques were used in the collection and identification of lichens. An index of species specificity of lichens for forophytes was calculated. An annotated list consists of 37 species and includes the information about their preferential forophytes.

Photodynamic treatment (PDT) causes a significant increase in the permeability of the blood-brain barrier (BBB) in healthy mice. Using different doses of laser radiation (635 nm, 10–40 J/cm2 ) and photosensitizer (5-aminolevulinic acid – 5-ALA, i.v.), we found the optimal PDT for the reversible opening of the BBB, exhibiting brain tissue recovery 3 days after PDT. Further increases in the laser radiation or 5-ALA doses have no amplifying effect on the BBB permeability, but are associated with severe damage of brain tissues.