Comparison of nucleotide sequences of ribosomal DNA of the mosquito genera Aedes and Ochlerotatus (Diptera: Culicidae: Aedini)

Morphological study allowed identifying 9 species of mosquitoes of the genus Ochlerotatus and 2 species of the genus Aedes. Sequencing of the rDNA region was performed for all these speciemens. The sequences of rDNA were the following: A. cinereus -868 bp, A. vexans--889 bp, Och. cantans--803 bp, O. excrucians--801 bp, O. euedes--794 bp, Och. cyprius--777 bp, O. diantaeus--758 bp, O. intrudens--817 bp, Och. punctor--783 bp, O. dorsalis--748 bp, O. species--767 bp. On average, the size of Aedes rDNA fragments exceeds rDNA of Ochlerotatus by 90-100 bp. The sequences are characterized by a high number of insertions and deletions, and also by point substitutions of nucleotides. It is important to notice that interspecific differences include not only different regions of the internal transcribed spacers, but also the conservative site which is represented by the 5.8S gene. Among four substitutions in this gene, one (C/A) represents the difference between Aedes and Ochlerotatus, the next (T/A) distinguishes A. cinereus from Ochlerotatus speciment and A. vexans, and two substitutions (A/C, T/G) testify the similarity between O. dorsalis and O. species and specimens of Aedes. Besides, two more deletions are typical for O. dorsalis and O. species. One deletion is com- mon, it distinguishes them from the other examined species, and another one is typical only for O. dorsalis. When analyzing morphological characteristics and comparing nucleotide rDNA sequences of O. species with the database, the similarity to O. caspius has been revealed. On the whole, phylogenetic relationships among Ochlerotatus species correspond to subdivision into groups based on morphological characters. Probably, examination of the larger number of specimens will change the morphological division into groups.     

Association study of renin-angiotensin system genes and hemostasis system genes with ischemic stroke among Russians of Central Russia

The analysis of alleles and genotypes frequencies of 14 SNP in genes of rennin-angiotensin system (REN, AGT, AGTR1, AGTR2, BKR2, ADRB2) and hemostasis system (FGB, F2, F5, F7, ITGB3, SERPINE1, MTHFR), as well as ACE insertion-deletion polymorphism in patients with stroke comparing to healthy controls matched by age, sex and ethnicity has been carried out. The genotyping procedure included the amplification of selected gene sequences following by hybridization of fluorescently labeled fragments with SNP-specific DNA probes. The analysis of allele frequencies of each gene separately revealed no statistically significant differences between groups of patients with stroke and healthy donors. Also the complex study has been performed to estimate the contribution of rennin-angiotensin system and hemostasis system genes to the genetic susceptibility to ischemic stroke among Russians from Central Russia using method MDR (Multifactor Dimensionality Reduction). The combination with increased risk for development of ischemic stroke was presented by complex genotype FGB G/- x ACE I/- x MTHFR C/- x SERPINE1 5G/5G (p = 0.03, OR = 2.4, 95% CI 1.1-5.3), which frequency was statistically significant higher in patients with stroke compared to healthy control.     

Karyotypes divergence in superspecies complex Cricetulus barabensis sensu lato and their interrelationships in natural contact zones

Interrelationships between three chromosomal forms of striped hamsters belonging to the superspecies complex Cricetulus barabensis sensu lato (Cricetidae, Rodentia), namely 'barabensis', 'pseudogriseus', and 'griseus', are examined from the standpoint of different biological/genetic species concepts. Craniometric data suggest that differences between the karyotypes are rather of subspecies level. Cytogenetic differences between the karyotypes are also not great and correspond to the level of chromosomal races within a single species. The analysis of mitochondrial gene for cytochrome b (cytb) indicates the level of differences between forms of about 2.3-4.1%. Such a level may correspond to intraspecific differences as well as to differences between allied species. Experiments on hybridization resulted in hybrid litters obtained in different mating combinations of karyotypes. Both hybrid males and females fertility was confirmed, too. In nature, there exist several zones where contact between karyotypes 'barabensis' and 'pseudogriseus' is possible. Within one of such zones, in Central Mongolia, two males with atypical karyotype were detected by use of chromosome analysis. With chromosomes number and form, this karyotype may correspond to the hybrid between second and subsequent generations. However, typing of gene cytb and the intron localized in Y-chromosome (DBY1) did not reveal any traces of recent or ancient hybridization. In the other zone where contact between the karyotypes is possible, in South Buryatia, 'barabensis' and 'pseudogriseus' populations are separated by the River Chika and the distance between them does not exceed 5 km. Nevertheless, no hamsters with non-standard karyotypes and no traces of gene flow are detected by karyological and molecular analyses of these populations. The results of Tajima's test, analysis of pairwise differences distribution and indices of nucleotide diversity obtained in the course of examining gene cytb full nucleotide sequence all suggest that both contact zones studied have formed long ago and the absence of gene flow cannot be explained by their forming in the recent past. Thus, the karyotypes studied appear to be evolutionary lines developing independently from each other.     

Antineoplastic effect of hydrogel prospidin on seidel ascites hepatoma used as a model

Antineoplastic effect of hydrogel dextran phosphate, hydrogel prospidin, and prospidin in an injectable preparation has been assessed using Seidel ascites hepatoma as a model. Injectable and hydrogel prospidin in doses from 250, 500 to 1000 mg/kg and hydrogel phosphate dextran in doses of 500 and 1000 mg/kg were administered to rats intraperitoneally in a single dose in a volume of 1 or 2 ml per each 100 g of animal body weight. The study has shown that irrespective of rats with Seidel ascites hepatoma and significantly increase in the dosage of prospidin preparations and hydrogel dextran phosphate results in a longer average life expectancy of rats Compared with its injectable variant, hydrogel prospidin appears to produce more than twice as high antineoplastic effect, and is found to provide prolonged therapeutic effects, as well as cure of animals in more than 60 % of cases.     

Conductive hearing loss caused by eustachian tube dysfunction according to the data of functional computed tomography

The paper deals with computed tomography (CT) diagnosis of Eustachian tube dysfunction. A functional multislice spiral (MS) CT protocol has been first elaborated for the Eustachian tube. Twenty-three patients with unilateral conductive hearing loss and Eustachian tube dysfunction were examined. The normal functional anatomy of the Eustachian tube was evaluated on the side without evidence of pathology in 23 patients. Functional MSCT showed that the cartilaginous portion of the Eustachian tube opened partially and closed completely in 9 patients. Ten patients were found to have steady changes in the cartilaginous portion of the Eustachian tube. The developed method could confirm the cause of conductive hearing loss and optimally define a treatment policy.     

Isolation of tropomyosin particles from the cytosol of cultured cells and their protein composition analysis

The presence of actin-binding protein, tropomyosin, shaped as particles or protein complexes that have no bonds with actin structures were found while the analisys of structural rearrangements of actin cytoskeleton. However, their functioning is still unknown. To study the composition and properties of these protein complexes a novel method of their separation from the cells without destroying the structures of the cytoskeleton have been developed. The protein composition of isolated tropomyosin particles has been analised by gel filtration, electrophoresis and Western blotting. They appeared to be a multimolecular complexes of about 700 kDa. Beside the tropomyosin and actin these complexes also contain the Hsp70, Hsp90 and myosin-9 identified by mass spectrometry analisys. Also, under inhibition of deacetylases by trichostatin A, changes in the number of particles and redistribution of tropomyosin between cytosol and cytoskeleton take place along with actin cytoskeleton rearrangements. The results obtained give a reason to assume that these multimolecular complexes may participate in the process of reorganization of the actin microfilaments.     

Temporal characteristics of the initial stage of the verbal information processing in healthy subjects and in schizophrenia

The study aimed to investigate the early coding of visually presented words and pseudowords using event-related potentials (ERP). We conducted comparative analysis of the characteristics of P100 and N170 in healthy controls and in patients with the first episode of schizophrenia during passive perception of verbal stimuli as well as under conditions of relevant words and pseudowords. The latency of early ERP components P100 and N170 appeared to be shorter in comparison with healthy subjects in the temporal, parietal and occipital areas. The latency of P100 in patients was significantly shorter in the temporal, parietal and occipital areas, whereas the latency of N170 was shorter in the parietal and occipital areas than in controls. The latency of N170 in healthy subjects was significantly longer to words than to pseudowords and in patients - vice versa. The latencies of N170 in all TPO areas were equal in healthy subjects during word processing, and this equality was upset during non-word processing. In patients with schizophrenia the equality was upset, but, opposite to healthy patients, the upset of equality was more expressed during words processing. Thus, the early stage of verbal information processing in schizophrenic patients is insufficient in time. The time deficit of the automatic processes may lead to defective processing of overall information.     

Fast and aimed delivery of voltage-sensitive dyes to mammalian brain slices by biolistic techniques

Fast voltage-sensitive dyes (VSD) are widely used in modern neuroscience for optical recording of electrical potentials at many levels, from single cell compartment to brain areas, containing populations of many neural cells. The more lipophilic a VSD, the better signal-to-noise ratio of the optical signal, but there are no effective ways to deliver a water-insoluble dye into the membrane of live cell. Here we report a new protocol based on rapid biolistic delivery of VSDs, which is optimal for further recordings of optical signals from live neurons of rat brain slices. This protocol allows us to stain locally (150 mkm) neural somata of brain structures with a Golgi-like pattern, and a VSD propagates even to distant neurites of stained cells very quickly. This technique also can be used for rapid local delivery of any lipophilic and water-insoluble substances into live cells, further optical recording of neural activity, and analysis of potential propagation in a nerve cell.