The Lena River in the Laptev Sea forms a vast delta, one of the largest in the world. The Ust-Lensky State Nature Reserve saves biodiversity on the Lena Delta territory beyond the Arctic Circle, in the zone of continuous permafrost. In recent years, large-scale plans for the development of extractive industries are implemented in this Russian Arctic sector. In this regard, the study of biodiversity and bioindication properties of aquatic organisms in the Lena River estuary area is becoming more and more relevant. This study aims to identify the species composition of microalgae in lotic and lentic water bodies of the Lena River Delta and use their indicator property for water salinity. It was a trace indicator of species distribution over the delta and their dynamics along the delta main watercourses to assess the impact of river waters on the Laptev Sea coastal areas. For this, all previously published materials on algae and chemical composition of the region waters as well as data obtained in recent years for the waters of the lower Lena reach were involved. In total, 700 species considered to 10 phyla were analyzed: Cyanobacteria (83), Euglenozoa (13), Ochrophyta (Chrysophyta, Xanthophyta) (41), Eustigmatophyta (4), Bacillariophyta (297), Miozoa (20), Cryptophyta (3), Rhodophyta (1), Chlorophyta (125), and Charophyta (111). The available materials of the field and reference observations were analyzed using several statistical methods. The study results indicate that hydrological conditions are the main factor regulating the spatial structure of the species composition of the microalgae communities in the Lena River Delta. The distribution of groups of salinity indicators across flowing water bodies reflects the effect of water salinity, and this allows suggesting possible sources of this effect. The mechanism of tracking the distribution of environmental indicators itself is a sensitive method, that reveals even their subtle changes in them; therefore, as an integral method, it can be helpful for further monitoring.

A first generalization of all available data on algal flora of the Lena River estuary has been performed. As a result of the revision of the data obtained in accordance with modern taxonomic reports, a species list of algae has been identified (646 species). It is established that the taxonomic structure of algae characterizes the water bodies as arctic undisturbed. Our analysis shows that the Lena River, being a large transiting waterway, shifts boreal flora to the Arctic region. In the zone where seawater and freshwater mix, signs of an edge effect are revealed. The influence of marine flora on all studied water bodies of the lower Lena River (drift of marine and brackish-water algae species) is established.

Recently, we identified the yeast red pigment (RP), a polymer of 1-(5'-Phosphoribosyl)-5-aminoimidazole, as a novel potential anti-amyloid agent for the therapy of neurodegenerative diseases. The purpose of this study was to further validate RP for treatment of Parkinson's disease (PD) and to clarify molecular mechanisms involved in the reduction of amyloid cytotoxicity. We investigated RP effects in vivo using Saccharomyces cerevisiae and Drosophila melanogaster PD models. Western blot analysis revealed reduction in the levels of insoluble a-synuclein in both models, while soluble a-synuclein decreased only in Drosophila. In both models RP significantly reduced a-synuclein cytotoxicity, as was revealed by immunohistochemistry in Drosophila (p < 0.001, n = 27 flies per genotype/assay) and by flow cytometry in yeast (p < 0.05). Data obtained from the yeast PD model suggests that RP antitoxic effects are associated with a drop in ROS accumulation, and slower cellular transition from the early to late apoptotic stage. Using Drosophila brain tissue sections, we have demonstrated that RP helps to compensate for an a-synuclein-mediated reduction in the number of dopaminergic neurons and leads to better performance in animal climbing tests (p < 0.001, n = 120-150 flies per genotype/assay). Taken together, these results demonstrate the potential of RP for the treatment of PD, at least in model systems.

Two transgenic yeast strains expressing human α-synuclein were used to study the impact of yeast red pigment exhibiting antiamyloid properties. It has been demonstrated that the endogenous red pigment produced under special conditions in strains carrying an ade1 mutation inhibits the expression of the hybrid protein α-synuclein-GFP. This was evident from the reduced mean value of GFP fluorescence and diminished number of cells accumulating cytoplasmic inclusions of α-synuclein-GFP. Exogenous forms of the purified red pigment (natural, synthetic and hydrolyzed derivatives) differ from the endogenous red pigment by their effect on α-synuclein. Exogenous red pigments increased the number of both cells expressing GFP fluorescence and those containing cytoplasmic inclusions. However, both endogenous and exogenous red pigments reduced the cloned α-synuclein toxicity and resulted in redistribution of the α-synuclein in cells. α-Synuclein content decreased in cell lysate pellets and increased in supernatants.

Taxonomic and ecological-floristic analysis of the phytoplankton and periphyton of the Timpton River and a few floodplain lakes are given. Quantitative parameters of number and biomass of phytoplankton of studied water bodies are presented.

The acute toxicity and antiarrhythmic activity of amino-, alkylamino-, and dialkylaminoacetic acid orthotoluides have been basically determined by the lipophilic properties and spatial effects of substituents when an amino nitrogen atom is present.

The acute toxicity (LD50) and antiarrhythmic activity of orthotoluides of amino, alkylamino, and dialkylaminoacetic acids are basically determined by the lipophilic properties and spatial effects of substituents when an aminonitrogen atom is present.

The study has shown that the nature and position of a substituent in the aromatic ring substantially affect the antiarrhythmic activity of diethylaminoacetic acid arylamides. The orthosubstituted arylamides display the highest activity while the meta- and parasubstituted arylamides are virtually inactive. The antiarrhythmic activity of the compounds in question correlates with electron and surface effects of orthosubstituents in the aromatic ring and with the surface activity of the above compounds.