Selenium Nanocomposites Having Polysaccharid Matrices Stimulate Growth of Potato Plants in Vitro Infected with Ring Rot Pathogen.

The influence of nanocomposites (NC) of selenium in matrices of arabinogalactan (Se/AG) and starch (Se/St) on in vitro vegetation of potato plants, peroxidase activity, and reactive oxygen species has been thoroughly studied. It has been shown that these nanocomposites of selenium have antimicrobial effect to the phytopathogenic bacterium Clavibacter michiganensis ssp. sepedonicus (Cms). In the present investigation, it has been shown that Se/AG NC (6.4% of Se) and Se/St NC (12.0% of Se) have no negative impact on the potato plants healthy and Cms infected, while stimulating their growth, number of leaves and weight of the vegetative part. Se/AG NC has shown a positive effect on potato plants by increasing its immune status by increasing the ROS content and increasing the peroxidase activity. With the use of the element analysis technique, it has been shown that scrutinized nanocomposites are not accumulated in potato plants after the bactericidal processing with the nanocomposites. Se/AG NC and Se/St NC as potential agents used for treatment of potato plants against pathogenic bacteria.

Complex Analysis of Diffusion Transport and Microstructure of an Intervertebral Disk.

We studied the relationship between diffusion transport and morphological and microstructural organization of extracellular matrix of human intervertebral disk. Specimens of the lumbar intervertebral disks without abnormalities were studied ex vivo by diffusion-weighed magnetic resonance imaging, histological and immunohistochemical methods, and electron microscopy. Distribution of the diffusion coefficient in various compartments of the intervertebral disk was studied. Significant correlations between diffusion coefficient and cell density in the nucleus pulposus, posterior aspects of annulus fibrosus, and endplate at the level of the posterior annulus fibrosus were detected for each disk. In disks with nucleus pulposus diffusion coefficient below 15×10-4 mm2/sec, collagens X and XI were detected apart from aggrecan and collagens I and II. The results supplement the concept on the relationship between the microstructure and cell composition of various compartments of the intervertebral disk and parameters of nutrient transport.

Extracellular Actin in Health and Disease.

This review considers the functions of extracellular actin - cell surface bound, associated with extracellular matrix, or freely circulating. The role of this protein in different pathological processes is analyzed: its toxic effects and involvement in autoimmune diseases as an autoantigen. The extracellular actin clearance system and its role in protection against the negative effects of actin are characterized. Levels of free-circulating actin, anti-actin immunoglobulins, and components of the actin clearance system as prognostic biomarkers for different diseases are reviewed. Experimental approaches to protection against excessive amounts of free-circulating F-actin are discussed.

Microbial Community Associated with Thioploca sp. Sheaths in the Area of the Posolski Bank Methane Seep, Southern Baikal.

Bacterial mats formed by a colorless sulfur bacterium Thioploca sp. in the area of the Posolski Bank cold methane seep (southern Baikal) were -studied using electron microscopy and phylogenetic analysis. Morphologically the bacteria were identified as Thioploca ingrica.- Confocal microscopy of DAPI-stained samples revealed numerous rod-shaped, filamentous, and spiral microorganisms in the sheaths, as well as in- side and between the trichomes. Transmission electron microscopy revealed nonvacuolated bacteria and small cells-without cell envelopes within the sheath. Bacteria with pronounced intracytoplasmic membranes characteristic; of type I methanotrophs were observed at the outer side of the sheath. Based on analysis of the 16S rRNA gene sequences, the following phyla were idenified in the sheath community: Bacteroidetes, Nitro- spira, Chloroflexi, Planctomycetes, Verrucomicrobia,'y-, and 6-Proteobacteria, Euryarchaeota, Crenarchaeota, and Thaumarchaeota, as well as anammox bacteria. A hypothetical scheme of matter flows in the Lake Baikal bacterial mats was proposed based on the data on metabolism of the cultured homologues.

Level of Blood Cell-Free Circulating Mitochondrial DNA as a Novel Biomarker of Acute Myocardial Ischemia.

Changes in the level of blood cell-free circulating mitochondrial DNA were examined during experimental adrenaline-induced myocardial injury in rats. The amount of mitochondrial DNA in the blood was significantly elevated at 48 and 72 h after subcutaneous injection of adrenaline solution, and it was accompanied by development of multiple small-focal myocardial ischemia. This suggests that the measured level of blood cell-free circulating mitochondrial DNA might be used as a biomarker of acute myocardial ischemia.

[Mechanisms of mitochondrial dysfunction development in vessels upon peroxidizes LDL influence].

The mechanisms of mitochondrial dysfunction development in vessels upon peroxodized LDL (pLDL) influence are discussed. Is is shown that the components of pLDL induce the formation of covalent complexes with cell proteins and destabilize cellular membrane microdomain structure that leads to membrane proteins dysfunction, Ca2+ liberation into cytosol from its stores, endoplasmic reticulum stress, increase in reactive oxygen species production by NADPH-oxidases. These effects cause disturbances in mitochondria of target cells, increases in reactive oxygen species production, mitochondrial pathway of cell death. The processes under discussion contribute to the atherosclerotic leisure development.

[Specific features of blood cell composition and structure in fishes from the pelagial and coastal zones of Lake Baikal].

Differences in the proportions and ultrastructure of peripheral blood cells between the Baikal cisco and roach have been revealed. Both species contain all main cell types involved in the immune response in higher vertebrates. However, cells mediating the innate immune response are represented in the Baikal cisco only by monocytes and pseudogranulocytes, whereas the blood of roach additionally contains true granulocytes. Significantly greater numbers of leukocytes and thrombocytes per unit volume in the roach are evidence for mobilization of the immune system in this species. The peripheral blood of both species contains lymphocytes, which are responsible for adaptive immunity. The content of hemoglobin in erythrocytes is lower in the roach than in the Baikal cisco. The state of blood in the two species may be considered adapted to typical conditions in their habitats.

[Identification of two cyanobacterial strains isolated from the Kotel'nikovskii hot spring of the Baikal rift].

Two cyanobacterial strains, Pseudanabaena sp. 0411 and Synechococcus sp. 0431, were isolated from a sample collected in the Kotel'nikovskii hot spring of the Baikal rift. According to the results of light and transmission electron microscopy, as well as of the phylogenetic analysis of the 16S rRNA gene, these cyanobacteria were classified as Pseudanabaena sp. nov. and Synechococcus bigranulatus Skuja. The constructed phylogenetic tree shows that the studied strains are positioned in the clades of cyanobacteria isolated from hydrothermal vents of Asia and New Zealand, separately from marine and freshwater members of these genera, including those isolated from Lake Baikal.

[Nitrogen-fixing cyanobacterium Trichormus variabilis of the lake Baikal phytoplankton].

A new filamentous cyanobacterial strain BAC 9610 was isolated from the lake Baikal pelagial. Data obtained by light, scanning, and transmission electron microscopy, along with 16S rRNA gene sequence analysis, allowed the bacterium identification as Trichormus variabilis, previously known as Anabaena variabilis. Trichormus is a cyanobacterial genus not presented in the list of Baikal plankton algae; A. variabilis also has not been previously detected in Baikal phytoplankton. T. variabilis nitrogen fixation ability was demonstrated. The gene responsible for nitrogen fixation, nifH, was identified by PCR and was partially sequenced. No hepatotoxin synthesis genes were revealed in the strain.

[Use of electron microscopy for study of animal brain synaptosomes]. / Ispol'zovvanie metodov élektronnoi mikroskopii dlia otsenki sostoianiia sinaptosom mozga zhivotnykh.

Studies were carried out on the fraction of animal brain synaptosomes obtained by the method of differential centrifugation. We studied the possibility of using electron microscopy of ultrathin section and freeze-etching for assessment of the state of synaptosomal membranes and functional state of synaptosomes. The method of freeze-etching proved to be the most informative. In order to assess the state of synaptosomes, the following characteristics were used: coefficient of lateral diffusion and asymmetric distribution of intramembrane particles. It was also possible to identify mitochondria in the synaptosomal fraction using freeze-etching, which is an important criterion of purity of the suspension of synaptosomes.

[The ultrastructural characteristics of olfactory receptor cells with different levels of sensitivity]. / Ul'trastrukturnye osobennosti oboniatel'nykh retseptornykh kletok raznykh urovnei chuvstvitel'nosti.

Structural and functional properties of the animals olfactory analyzer were studied on different stages of their life. Attention was drawn to defining the correlations between the ultrastructure of primary sensory cells, their sensitivity and realization of adaptive behavior in fish in diverse reproductive period stages. Structural organization in fish olfactory cells appearing during spawning aim both to activate these cells to provide specific receptor function during intercourse and to urgently abolish it when transitioning to paternal behaviour. Not only central mechanisms of nervous system but also reorganizations of peripheral chemoreceptive apparatus are of great importance, which is demonstrated for the first time.