Method for microplastics extraction from Lake sediments.

In recent years, microplastics (MPs) contamination has been emphasized as one of the most global ecological problems. Bottom sediments were identified as one of the major sinks of MPs, while river-lake systems - as the main transport routs of MPs into the coastal seas and the World Ocean. Thus, the MPs determination in freshwater sediments is an important task for identifying sedimentation processes and contamination sources. Density separation is commonly used to extract anthropogenic particles from bottom sediments. The proposed method is dedicated to determining the abundance of MPs in freshwater organic-rich sediments. Repeated wet peroxide oxidation was applied to digest organic matter that can hamper the microplastic determination in a sample. Potassium formate with a density 1.5 g/mL was used as a separation solution. This method is intended to identify various types of MPs (fibers, films, fragments and beads) ranging in size from 0.174 to 5 mm. The effectiveness of the MPs extraction with potassium formate was 98.0 ± 2 % (р = 0.05; n = 16), while the extraction of MPs when analyzed under a microscope was 92.0 ± 4% (р = 0.05; n = 20).

Synchronization of infra-slow oscillations of brain potentials with respiration.

We study the synchronization of infra-slow oscillations in human scalp electroencephalogram signal with the respiratory signal. For the cases of paced respiration with a fixed frequency and linearly increasing frequency, we reveal the phase and frequency locking of infra-slow oscillations of brain potentials by respiration. It is shown that for different brain areas, the infra-slow oscillations and respiration can exhibit synchronous regimes of different orders.

[Prevalence of VRN1 Locus Alleles among Spring Common Wheat Cultivars Cultivated in Western Siberia].

With the use of allele-specific primers developed for the VRN1 loci, the allelic diversity of the VRN-A1, VRN-B1, and VRN-D1 genes was studied in 148 spring common wheat cultivars cultivated under the conditions of Western Siberia. It was demonstrated that modern Western Siberian cultivars have the VRN-A1a allele, which is widely distributed in the world (alone or in combination with the VRN-B1a and VRN-B1c alleles). It was established that the main contribution in acceleration of the.seedling-heading time is determined by a dominant VRN-A1a allele, while the VRN-A1b allele, on the contrary, determines later plant heading. Cultivars that have the VRN-A1b allele in the genotype are found with a frequency of 8%. It was shown that cultivars with different allele combinations of two dominant genes (VRN-A1a + VRN-B1c and VRN-A1a + VRN-B1a) are characterized by earlier heading and maturing.

[ENTRY OF FACULTATIVE PATHOGEN SERRATIA GRIMESII INTO HELA CELLS. ELECTRON MICROSCOPIC ANALYSIS].

Facultative pathogens Serratia grimesii are able to invade eukaryotic cells where they have been found in vacuoles and free in the cytoplasm (Efremova et al., 2001; Bozhokina et al., 2011). However, efficiency of this invasion is low, and the mechanisms of the invasion related to the initial steps of the process are not known. In the present study, we have increased the invasion efficiency by incubation of HeLa cells with N-acetylcysteine (NAC) preceding the infection. In the NAC-pretreated cells, two modes of S. grimesii to enter HeLa cells were observed. In the most cases, the penetration of S. grimesii into the cell was consistent with the "zipper mechanism", involving specific interaction of bacterial invasin with a host cell surface receptor. However, in some cases, bacteria were trapped by membrane ruffling probably produced by injected bacterial proteins that trigger the bacterial uptake process, as described in the "trigger mechanism". Further elucidation of bacterial and cellular factors involved in the bacteria-host cell interaction should clarify whether two different mechanisms or a predominant one operate during S. grimesii invasion.

[Chromosome composition of wheat-rye lines and the influence of rye chromosomes on disease resistance and agronomic traits].

Identification of the chromosomal composition of common wheat lines with rye chromosomes was carried out using genomic in situ hybridization and 1RS- and 5P-specific PCR markers. It was demonstrated that wheat chromosomes 5A or 5D were substituted by rye chromosome 5R in the wheat-rye lines. It was established that one of the lines with complex disease resistance contained rye chromosome 5R and T1RS.1BL, while another line was found to contain, in addition to T1RS.1BL, a new Robertsonian translocation, T5AS.5RL. Substitution of the wheat chromosome 5A with the dominant Vrn-A1 gene for the Onokhoiskaya rye chromosome 5R led to lengthening of the germination-heading period or to a change in the type of development. A negative influence of T1RS.1BL on SDS sedimentation volume and grain hardness was demonstrated, along with a positive effect of the combination of T1RS. BL and 5R(5D) substitution on grain protein content. Quantitative traits of the 5R(5A) and 5R(5D) substitution lines were at the level of recipient cultivars. A line with two translocations, T1RS.1BL + T5AS.5R1, appeared to be more productive as compared to the line carrying T1RS.1BL in combination with the 5R(5D) substitution.

[Influence of Vrn-B1a and Vrn-B1c alleles on length of developmental phases of substitution and near-isogenic lines of common wheat].

The influence of Vrn-B1a and Vrn-B1c alleles on the length of developmental phases in lines of winter cv. Sava with intervarietal substitution of chromosomes 5B and near-isogenic lines (NILs) with these loci in the genetic background of winter cv. Bezostaya 1 is studied. We have confirmed that effects of Vrn genes appear on the tillering phase and that the response to vernalization and shortening of day length can change the duration of this phase. We have shown that, after vernalization and under short-day conditions, the Vrn-B1a allele has the strongest effect on the length of the tillering phase. After vernalization, in the late substitution line Sava (Diamant II 5B) with the Vrn-B1a allele, the length of the tillering decreased more strongly after 6 days than in the earlier Sava line (Saratovskaya 29 5B) with the Vrn-B1c allele. After the length of the day shortens, in late NIL i:Bez1 Vrn-B1a, the length of the tillering phase and period of stem elongation--heading increased more strongly for 13 and 5 days, respectively than in the early i:Bez1 Vrn-B1c line. The study of F1 hybrids between substitution and isogenic lines, the growth habits of which are determined by both Vrn-B1a and Vrn-B1c alleles, had shown the dominance of the trait lateness, which is determined by the line with the Vrn-B1a allele. In F1 hybrids, between substitution lines, the length of tillering was similar to that of the line with Vrn-B1a and, in F1 hybrids between NILs, the length of tillering was intermediate between the parental lines.

[Characterization of puroindolines in the control of endosperm texture in common wheat lines with substitutions of homeologous group-5 chromosomes].

The genetic control of grain hardness and its association with the specific friabilin content on starch granules of common wheat cultivars and lines with intervarietal substitutions of homeologous group-5 chromosomes were studied. A significant correlation was revealed between the technological parameters of grain hardness (mean size of flour particles) and the specific content of puroindolines on the starch surface estimated in terms of starch doses. The results obtained allowed the method of starch doses to be used to identify soft and hard wheat cultivars and lines based on an analysis of a single grain. The biochemical analysis confirmed the previously obtained estimates of flour-grinding properties of wheat cultivars and substitution lines, which allowed specific genotypes to be characterized according to the composition of puroindolines. The influence of chromosomes 5D and 5A of donor wheat cultivars on the activity of the Ha loci of recipient cultivars was revealed and found to be associated with the composition of PIN products and with the expression of the Pina-D1 and Pinb-D1 genes.

The effect of two differentially expressed wheat VRN-B1 alleles on the heading time is associated with structural variation in the first intron.

We measured the level of VRN-B1 transcripts within near-isogenic lines of Triticum aestivum cultivar 'Bezostaya 1' carrying two VRN-B1 alleles from cultivars 'Saratovskaya 29' and 'Diamant 2' (VRN-B1c and VRN-B1a, respectively). Both lines have similar kinetics of VRN-B1 transcript accumulation at the third to fifth leaf stages. However, quantitative PCR analysis at the third leaf stage showed that the VRN-B1c allele was transcribed 10 times faster than the VRN-B1a allele. The F1 hybrid between the lines is more similar to the line carrying the VRN-B1a allele with regard to the level of VRN-B1 transcription. The difference in the transcript levels of the VRN-B1 alleles appears to be due to the previously identified structural changes in the first intron of VRN-B1c (deletion of 0.8 kb and duplication of 0.4 kb) as compared with VRN-B1a, as no other differences were revealed in the present study. We suggested that the first intron structural changes in the VRN-B1c allele as compared with VRN-B1a result in a higher level of VRN-B1 transcripts and an earlier heading time. We confirmed that the expression of the dominant VRN-1 gene induces transcription of the recessive homoeoalleles, coupled with the reduction of the transcript level of a flowering repressor VRN-2.

[Spatial structure of acid properties of litter in the succession row of swamp birch woods ].

The general potential, exchange, and actual (pH) acidities were investigated in the litter of the succession row of swamp birch woods. Their variabilities constitute, respectively, 75.9-174.4, 3.7-25.8 mmol (+)/100 g of the sampling, 3.7-5.5. For the first time, using the methods ofgeostatistics, their spatial variability was analyzed and the contributions of the trend, autocorrelation component, and the radius of the spatial correlation were estimated. It was established that in combination with the tree waste, which is uniformly distributed along the ecological profile, the specific composition of the grass-moss tier, which corresponds to the humidity of edaphon, forms the picture of the spatial structure of acid properties of the litter. It was noted that the prime cause of variability consists in the particularities of the water regime of the habitats of swamp birch woods.

[A cytogenetic study of the blue-grain line of the common wheat cultivar Saratovskaya 29].

The chromosome composition of the blue-grain line i:S29Ba of the cultivar Saratovskaya 29 was identified by cytological, GISH, and microsatellite analyses and C-banding. It was found that common wheat chromosome 4B of the cultivar Saratovskaya 29 was substituted with the Agropyron elongatum Host. chromosome carrying the gene for blue grain (s:S294Ag(4B)) during the construction of this nearly isogenic line. The blue-grain line was tested for productivity. The substitution of total chromosome 4B of the cultivar Saratovskaya 29 by Ag. elongatum chromosome 4 did not significantly affect the spike productivity parameters and grain quality with the exception of spike length (plus effect), spike density, and vitreousness (minus effects). The blue-grain line with s:S294Ag(4B) can be used in further studies associated with chromosome engineering in cereals and wheat breeding.

[Assembly of actin filaments induced by sequestration of membrane cholesterol in transformed cells].

Cholesterol is one of the major lipid components of plasma membrane and it plays an important role in various signaling processes in mammalian cells. Our study focused on the role of membrane cholesterol in organization and dynamics of actin cytoskeleton. Experiments were performed on cultured transformed cells characterized by weakly developed actin network and reduced stress fibers--human embryonic kidney HEK293 cells, epidermoid larynx carcinoma HEp2 cells and mouse fibroblasts 3T3-SV40. Using F-actin labeling with rhodamine-phalloidin, actin cytoskeleton rearrangements were analyzed after sequestration of membrane cholesterol by cyclic oligosaccharide methyl-beta-cyclodextrin, and polyene macrolide antibiotic filipin. In cells treated with methyl-beta-cyclodextrin or filipin, similar processes of actin cytoskeleton reorganization involving filament assembly were revealed. In carcinoma HEp2 cells and fibroblasts 3T3-SV40, cholesterol-sequestering reagents induced intensive stress fiber formation and enhanced cell spreading which corresponded to reversion of transformed phenotype. The rearrangements of cytoskeleton are likely initiated by disruption of lipid raft integrity that is critically dependent on the level of the membrane cholesterol.

[The role of chromosomes from homeologous group 5 in regulation of grain hardness and protein content in substitution lines of common wheat cultivar Saratovskaya 29].

Genetic regulation of grain hardness and protein content in intervarietal substitution lines for chromosomes of homeologous group 5 was examined. Common wheat cultivar Saratovskaya 29 with high bread-backing properties served as the recipient. Donors of chromosomes 5A and 5D were 18 cultivars with variable traits examined, including high-protein cultivars (Atlas 66 and Diamant 2), and soft-grain cultivars (Ul'yanovka and Chinese Spring). Analysis of substitution lines pointed to a substantial effect of chromosome 5D on the regulation of both traits. It was demonstrated that as a result of intervarietal substitution for chromosome 5D from donor cultivars Ul'yanovka and Chinese Spring, the endosperm softness was increased compared to the recipient cultivar Saratovskaya 29. Substitution lines Saratovskaya 29/Atlas 66 5D and Saratovskaya 29/Diamant 2 5D were characterized by high grain protein content, as well as by high endosperm softness. In addition, the line Saratovskaya 29/Novosibirskaya 67 5D, characterized by grain hardness higher than in Saratovskaya 29, was isolated. In the lines with intervarietal substitution of chromosome 5A, grain protein content was found to be lower than in recipient cultivar Saratovskaya 29.

[Analysis of spike productivity traits in near-isogenic lines of the common wheat cultivar Saratovskaya 29 carrying alien marker genes].

Six near-isogenic lines of the wheat cultivar Saratovskaya 29 carrying five marker genes from different species (Triticum compactum L., T. polonicum L., T. petropavlovskyi Udacz. et Migusch., Aegilops elongatum Host. and Secale cereale L.) were studied. It was shown that the introduced marker genes of taxonomic significance, C and P, have strong pleiotropic effects on quantitative traits of the spike productivity.

[The influence of Mycoplasma salivarium in the absence and presence of L-arginine on karyotypic variability in cell line of the Indian muntjak skin fibroblasts under long-term cultivation].

The influence of Mycoplasma salivarium on the numerical and structural karyotypic variability has been investigated in the "markerless" cell line of the Indian muntjak skin fibroblasts (line M) during long-term cultivation in the absence and presence of L-arginine. Cultivation of the mycoplasmal contaminated cells for 15 and 30 days did not change the character of cell distribution for the chromosome number. In the contaminated cells cultivated for 60 and 75 days, the character of cell distribution for the chromosome number was changed. These changes involved bimodal distribution for the chromosome number due to a significant decrease in the frequency of the cells with the modal number of chromosomes with main structural variant of karyotype (SVK)--2 + 2 + 1 + 1 + 1 and an increase in the frequency of cells with submodal number of chromosomes with main SVK--2 + 2 + 1 + 1. Besides, a significant increase in the frequency of the cells with lower chromosome number was observed in 60 days compared to that in 75 days of cultivation. Cultivation of the contaminated and control cells in the medium with increased concentration of L-arginine during 60 days did not change the numerical parameters relative to the control. Cultivation of the contaminated cells for 60 days followed by addition of L-arginine for 15 days restored the numerical parameters the numerical parameters to the control level. In the contaminated cells the frequency of chromosomal aberrations significantly increased for 30, 60 and 75 days cultivation relative to the control variant. In 30 days, the small but significant increase took place due to increase in the frequency of chromosomal aberrations of all the types. In 60 and 75 days, a greater increase took place due to a significant increase in the frequency of chromosomal and chromatid breaks. Moreover, in 60 days, the level of dicentrics (telomeric associations) mainly produced by chromosomes 1 and 2 increased significantly. The role of dicentrics as one of the ways for adaptation of the "markerless" cell lines to condition of cultivation and the role of L-arginine in the restoration of normal karyotypic structure of cell population of line M under mycoplasmal contamination are discussed.

Probing for actinase activity of protealysin.

The ability of protealysin, a thermolysin-like metallopeptidase from Serratia proteamaculans 94, to cleave actin and matrix metalloprotease MMP2 is reported. In globular actin, protealysin and S. proteamaculans 94 cell extracts are shown to hydrolyze the Gly42-Val43 peptide bond within the DNase-binding loop and the Gly63-Ile64 and Thr66-Ile67 peptide bonds within the nucleotide cleft of the molecule. At enzyme/substrate mass ratio of 1 : 50 and below, a 36 kDa-fragment produced by the cleavage between Gly42 and Val43 was virtually resistant to further breakdown. Judging from the results of zymography, protealysin transforms proMMP2 into a 66 kDa polypeptide characteristic of mature MMP2, indicating that protealysin can activate MMP2. Upon incubation of S. proteamaculans 94 with human larynx carcinoma Hep-2 cells intracellular bacteria were detected in about 10% of Hep-2 cells, this being the first evidence for invasion of eukaryotic cells with bacteria of this species. Thus, S. proteamaculans 94 turned out to be one more bacterial strain in which synthesis of actin-specific metalloprotease is coupled with bacterial invasion. These results are consistent with the idea of the actinase activity of bacterial metalloproteases being a factor that may promote bacterial invasion of eukaryotic cells.

[Production of alloplasmic and euplasmic wheat-barley ditelosomic substitution lines 7H(1)Lmar(7D) and analysis of the 18S/5S mitochondrial repeat in these lines].

Alloplasmic lines of common wheat with disomic substitution of chromosome 7D for telocentric chromosome 7H(1)Lmar of barley H. marinum subsp. gussoneanum Hudson were isolated from the plants of generation BC3, produced as a result of backcrossing of barley-wheat hybrids H. marinum subsp. gussoneanum (2n = 28) x x T. aestivum (2n = 42), Pyrotrix, cultivar, with 28 common wheat cultivars Pyrotrix 28 and Novosibirskaya 67. Chromosome substitution pattern was determined using SSR analysis and C-banding. In preliminary genomic in situ hybridization experiments, telocentric chromosomes were assigned to wild barley was established. In the BC3F8-generations of three alloplasmic lines with the 7H(1)Lmar(7D) substitution type the differences in fertility manifestation were observed: most of the L-32(1) plants were sterile, in line L-32(2) only sporadic plants were sterile, and line L-32(3) was fertile. Simultaneously with these experiments, using self-pollinated progeny of the hybrids obtained in crosses of common wheat cultivar Saratovskaya 29 (2n = 41), monosomic for chromosome 7D, with common wheat cultivar Pyrotrix 28 with addition of pair of telocentric chromosomes 7H(1)Lmar(7D) of barley H. marinum subsp. gussoneanum, euplasmic wheat-barley ditelosomic substitution 7H(1)Lmar(7D) lines were isolated. The lines obtained had normal fertility. PCR analysis of the 18S/5S mitochondrial repeat (hereafter, mtDNA sequence) in alloplasmic and euplasmic ditelosomic substitution lines 7H(1)Lmar(7D) was performed. In the plants from alloplasmic sterile line L-32(1), the sequences only of the barley (maternal) type were revealed, while the plants from alloplasmic fertile lines L-32(2) and L-32(3) demonstrated heteroplasmy (the presence of barley- and wheat-like sequences within one individual). In euplasmic ditelosomic substitution lines the presence of only wheat-like 18S/5S mitochondrial repeat sequences was observed. The results indicate that the presence of barley-like mtDNA sequences in alloplasmic substitution lines was not associated with the presence of barley chromosomes in their nuclear genomes.

[Oxidoreductase activity of peat soils as an indicator of the degree of biochemical transformation of drained and forested bogs in west Siberia].

Multivariate analysis unambiguously demonstrated the differentiation of oxidoreductase activity (catalase, peroxidase, and dehydrogenase) in peat soils after a 20-25-year period of bog drainage and afforestation. The enzyme activity depended on the drainage depth. A statistical model has been developed to predict the degree of humification of peat organic matter from peroxidase activity and moisture of drained soils. Soil peroxidase activity can be an important indicator of the degree of biochemical transformation of drained and forested bogs.

Decreased sensitivity of transformed 3T3-SV40 cells treated with N-acetylcysteine to bacterial invasion.

Long-term treatment of transformed 3T3-SV40 mouse fibroblasts with antioxidant N-acetylcysteine decreased cell level of ROS and increased the concentration of reduced glutathione. Removal of N-acetylcysteine from the medium led to the appearance of well-expressed stress fibrils, virtually absent in control cells. In contrast to control cells, these cells were not invaded by apathogenic Escherichia coli A2 strain producing ECP32 protease specifically cleaving actin. Antioxidant N-acetylcysteine can cause partial reversion of transformed phenotype at the expense of a shift of cell redox balance in favor of reduced glutathione.

[Genetic analysis of anthocyanin of the anthers and culm pigmentation in common wheat].

Anthocyanin pigmentation of various organs develops during plant ontogeny in response to adverse and damaging abiotic and biotic stressors (environmental factors). Using the monosome method, the genes responsible for anther and culm anthocyanin pigmentation (Pan1 and Pc2, respectively) were localized to 7D chromosome in introgressive lines from crosses between common wheat Triticum aestivum L. and the species Triticum timopheevii Zhuk. Genetic analysis of ten common wheat genotypes using testers carrying genes Pan1, Pn1, and Pn2 showed that these genotypes contained Pan1 and Pn2 genes. Visual examination of plants from 70 and 76 varieties of respectively winter and spring common wheat revealed anthocyanin pigmentation of anthers and culms in 36 varieties. Pan1 and Pn2 genes were presumably introduced into common wheat from Aegilops tauschii (Fig.) Tzvel., a donor of the D genome.

[Resistance to fungal diseases in hybrid progeny from crosses between common wheat variety Saratovskaia 29 and the amphidiploid Triticum timopheevii/Triticum tauschii (AAGGDD)]. / Izuchenie ustoichivosti k gribnym bolezniam potomstv gibridov ot skreshchivaniia sorta miagkoi pshenitsy Saratovskaia 29 s amfidiploidom--Triticum timopheevii/Triticum tauschii (AAGGDD).

The progeny of BC6F2-BC9F(2)-4 has been analyzed for resistance to brown rust (Lr genes) and powdery mildew (Pm genes). This progeny was obtained due to introgression of the alien material from the synthetic hexaploid wheat Triticum timopheevii/Aegilops squarrosa (= Triticum tauschii AAGGDD, 2n = 42) into the common wheat variety Saratovskaya 29. Against the background of natural infection, the lines resistant to both diseases and to either of them were developed. The brown-rust and powdery-mildew resistance is controlled by one/two effective independent genes Lr and Pm.