Structural Insight into Complexation Ability and Coordination of Uranyl Nitrate by 1,10-Phenanthroline-2,9-diamides.

Reprocessing of spent nuclear fuel (SNF) is an important task in a frame of ecology and rational use of natural resources. Uranium, as the main component of SNF (>95%), can be recovered for further use as fresh nuclear fuel. To minimize an amount of solid radioactive waste generated during SNF reprocessing, new extractants are under investigation. Diamides of 1,10-phenanthroline-2,9-dicarboxylic acid are perspective tetradentate N-donor ligands that form strong complexes with f-elements, which are soluble in polar organic solvents. As an example of three ligands of this class, we conducted a comparative study and showed how the substituent in the amide functional group affects the extraction ability toward uranyl nitrate from nitric acid media. We have performed a careful study (NMR, FT-IR, XRD, RMC-EXAFS) of the structures of synthesized complexes of new ligands with uranyl nitrate and used quantum mechanical calculations to explain the discovered regularities through.

[The associations of indices of echocardiography with polymorphism of genes of angiotensinogen and angiotensin receptor type I in examined patients with chronic rheumatic heart disease].

The purpose of study is to evaluate associations of polymorphism of genes encoding components of renin-angiotensin system and indices of echocardiography in examined patients with rheumatic heart disease (RHD). The sampling consisted of 128 patients with RHD and average age 58,96±0,34 years. The echocardiography was implemented using Philips Affinity 50 machine. The genetic typing was carried out according polymorphic markers Thr174Met, Met235Thr and А1166С by polymerase chain reaction in real-time with electrophoretic scheme of detecting the result of "SNP-EXPRESS". The heterozygosis of Thr174Met results in larger dilatation of left sections of heart. The Thr174Thr homozygotes characterized by large linear dimensions of right heart. The Thr235Thr homozygotes characterized by minimal parameters reflecting hypertrophy of left ventricle of heart. There was no significant difference in echocardiography indices in patients with A1166A polymorphism. The mutations in codon 235 and 174 did not affect distance of 6-minute walk test. The statistically significant difference in the distance of 6-minute walk test was obtained only for А1166С: the minimum distance indicators is in the group of A1166C heterozygotes - 291,46 (273,83-309,09) meters and the maximum distance in С1166С homozygotes - 357,20 (309,21-405,19) meters. In patients with RHD, Thr174Met heterozygosis can lead to dilatation of left heart camera, while homozygosis for Thr174Mr leads to dilatation of right heart camera and left ventricular hypertrophy. The Met235Thr heterozygosis, on the contrary, are characterized by minimal sizes of left atrium and right ventricle. Polymorphism of the A1166C gene encoding angiotensin type I receptor had practically no effect on echocardiography indices in patients with RHD.

[The role of ADRB1 genes polymorphism in examined patients with chronic rheumatic heart disease].

The study purpose is to evaluate effect of ADRB1 gene polymorphism on echocardiography indices and endothelial function in patients with chronic rheumatic heart disease. The sampling consisted of 128 patients with chronic rheumatic heart disease. The echocardiography was performed on Philips Affinity 50 device and evaluation of endothelial function was implemented on "AngioScan01" device. The genetic typing was carried out according polymorphic markers Gly49Ser and Gly389Arg. The nucleotide replacement of glycine with serine resulted in increasing of left sections of heart both at Ser49Ser (left atrium 5.65±0.09 cm; LVED 5.61±0.27 cm; LVES 3.76±0.16 cm), and Gly49Ser (left atrium 5.65±0.09 cm; LVED 5.61±0.27 cm; LVES 3.76±0.16 cm), The similar situation occurred when glycine was replaced with arginine: for Arg389Arg homozygotes (left atrium 5.63±0.12 cm; LVED 5.97±0.20 cm; LVES 3.97±0.16 cm); and heterozygotes Gly389Arg (LVED 5.60±0.08 cm; LVES 3.78±0.07 cm). Homozygosity of Ser49Ser in endothelial function led to low values of index augmentation (5.83±0.80%) and indicators reflecting function of small resistive arteries were the worst (1.30±0.07). Arg389Arg homozygotes had the worst endothelial function in system of large arteries (-20.40±0.68 ms). highest severity of arterial stiffness (23.00±0.68%) as compared with Gly389Gly homozygotes (8.92±0.99% and 62.67±1.41 years). ADRB1 gene polymorphism in subjects with HRBS leads to dilatation of left heart. The effect on endothelial dysfunction is multidirectional: Ser49Ser homozygosity leads to minimal arterial stiffness and changes in small resistive arteries; homozygosity of Arg389Arg leads to maximum changes in large conducting arteries and the highest rates of vascular stiffness.

Multistability of synchronous regimes in rotator ensembles.

We study collective dynamics in rotator ensembles and focus on the multistability of synchronous regimes in a chain of coupled rotators. We provide a detailed analysis of the number of coexisting regimes and estimate in particular, the synchronization boundary for different types of individual frequency distribution. The number of wave-based regimes coexisting for the same parameters and its dependence on the chain length are estimated. We give an analytical estimation for the synchronization frequency of the in-phase regime for a uniform individual frequency distribution.

Interaction-based transition from passivity to excitability.

In this paper we study the process of transition from passive to excitable behavior due to interaction between nonlinear dynamical systems. We show that under certain conditions a passive unit may demonstrate qualitatively new excitable dynamics. We study the properties of an excitable medium constructed on the basis of the proposed transition. The effects are demonstrated with the realistic Luo-Rudy model. Application to the cardiac dynamics and functioning is discussed. The qualitative analytic and numerical description is also given for the phenomenological FitzHugh-Nagumo system.

[Methods for the Crimean-Congo hemorrhage fever diagnosis].

Several distinct methods currently used for the Crimean-Congo Hemorrhage Fever diagnosis (CCHF) were suggested in this work. We demonstrated that the ELISA-based diagnostic kits, which are based on CCHFV recombinant antigens produced in E. coli cells, still possessed a few substantial shortcomings, which are yet to be addressed. In this work we presented the development of the unique CCHFV detection system fully based on reverse transcription--nested two-step polymerase chain reaction (RT-PCR). Our RT-PCR-based diagnostic kit for the CCHFV detection is now commercially available. We also developed a simple screening method for the samples, potentially containing CCHFV, which is based on restriction fragment length polymorphism (RFLP) amplicons analysis and allows for preliminary genotyping of the CCHFV isolates.

[The production of high-yielding strain of rubella virus from wild type virus extracted from a patient in the Western Siberia in 2006].

The study was targeted to investigate the propagation of rubella virus in the cell cultures of various origins and with different cultivation methods. The high-yielding strain of rubella virus was produced. The "spinner-culture" cultivation method was applied and the strain's RNA was detected in 10-8 dilution in real time mode. This strain is supposed to be used in preparation of the standard antigen to implement in the development of immune enzyme test system targeted to the rubella virus specific antibodies.

[Differentiation of genetic variants of Crimean-Congo hemorrhagic fever virus].

The paper describes a simple, rapid screening of samples potentially containing Crimean-Congo hemorrhagic fever (CCHF) virus strains, by applying the restriction analysis of amplicones, for the differentiation of CCHF virus genotypes that are characteristic of Europe from virus biovariants uncharacteristic of this area, this technique requiring no sequence at the first stage. For this screening, the authors propose to use the PCR fragment of CCHF L segment that comprises a variable region, as well as Alul and Haelll restriction endonucleases. The screening scheme proposed for samples potentially containing CCHF virus may aid investigators to monitor in order to detect uncharacteristic genotypic virus variants in the Russian Federation and other European countries.

[Entification of the Rubella virus genotype 1H in Western Siberia].

Molecular epidemiological study of novel strain of Rubella virus isolated during the outbreak in Western Siberia in 2004 was described. Detailed phylogenetic analysis performed based upon entire SP-region, which encodes all three Rubella structural proteins (C, E2, and E1), was implemented. This analysis provides characterization of this strain and classifies it as 1H genotype, thereby correcting previous classification of this strain based upon shorter nucleotide sequence, only encoding E1 protein. Therefore, this study identified the genotype of the Rubella virus not previously detected in Western Siberia (and even entire Russian Federation), which highlights the importance of more extensive characterization of genetic variability of the Rubella virus, especially with regard to potential influence of vaccination on the Rubella virus mutagenesis.

[Selenium provision in heart failure of different aetiology].

Determination of selenium status of patients with chronic heart failure of various etiologies showed reduced provision of selenium compared with the control group. Statistically significant increased serum levels of selenium have occurred on average 35,9% after the correction. Intake of sea cabbage jam led to a significant increase in the level of selenium in serum only at patients with deficiency of this trace constituent.

Distant synchronization through a passive medium.

This paper deals with the phenomenon of synchronization of oscillatory ensembles interacting distantly through the passive medium. Main characteristics of such a kind of synchronization are studied. The results of this work can be applied to describe the synchronization of cardiac oscillatory cells separated by the passive fibroblasts. In this work the phenomenological models (Bonhoeffer-Van der Pol) of cardiac cells as well as biologically relevant (Luo-Rudy, Sachse) models are used. We also propose equivalent model of distant synchronization and derive on its basis an analytical scaling of the frequency of synchronous oscillations.

Influence of passive elements on the dynamics of oscillatory ensembles of cardiac cells.

In this paper we focus on the influence of passive elements on the collective dynamics of oscillatory ensembles. Two major effects considered are (i) the influence of passive elements on the synchronization properties of ensembles of coupled nonidentical oscillators and (ii) the influence of passive elements on the wave dynamics of such systems. For the first effect, it is demonstrated that the introduction of passive elements may lead to both an increase or decrease in the global synchronization threshold. For the second effect, it is also demonstrated that the steady state of the passive element is a key parameter which defines how this passive element affects the wave dynamics of the oscillatory ensemble. It was shown that for different values of this parameter, one can observe increase or decrease in wave propagation velocity and increase or decrease in synchronization frequency in oscillatory ensembles with the growth of influence of passive elements. The results are obtained for the models of cardiac cells dynamics as well as for the Bonhoeffer-Van der Pol model and are compared with data of real biological experiments.

Synchronization phenomena in mixed media of passive, excitable, and oscillatory cells.

We study collective phenomena in highly heterogeneous cardiac cell culture and its models. A cardiac culture is a mixture of passive (fibroblasts), oscillatory (pacemakers), and excitable (myocytes) cells. There is also heterogeneity within each type of cell as well. Results of in vitro experiments are modelled by Luo-Rudy and FitzHugh-Nagumo systems. For oscillatory and excitable media, we focus on the transitions from fully incoherent behavior to partially coherent behavior and then to global synchronization as the coupling strength is increased. These regimes are characterized qualitatively by spatiotemporal diagrams and quantitatively by profiles of dependence of individual frequencies on coupling. We find that synchronization clusters are determined by concentric and spiral waves. These waves arising due to the heterogeneity of medium push covered cells to oscillate in synchrony. We are also interested in the influence of passive and excitable elements on the oscillatory characteristics of low- and high-dimensional ensembles of cardiac cells. The mixture of initially silent excitable and passive cells shows the transitions to oscillatory behavior. In the media of oscillatory and passive or excitable cells, the effect of oscillation death is observed.

[Analysis of genomes of two rubella virus strains from the 2004-2005 outbreaks in West Siberia].

Two outbreaks of rubella infections notified in the Tomsk and Kemerovo Regions were investigated. Two rubella virus strains from one patient in each outbreak were isolated and genetically characterized. Reverse transcription polymerase chain reaction was used to reveal partial E1 gene sequence at a length of 915 nucleotides. Analysis indicated that the rubella virus strains circulating in the West-Siberian region belonged to international genetic 1g group, which had been first detected in Russia.

[Clinical and immunological characteristics of rubella in western Siberia].

Evaluations of immune system of 155 patients with rubella and 90 contacts with patients were examined. Detection of viral genetic material in blood, urine, and nasopharyngeal swabs has been performed using RT-PCR method. Clinical diagnosis has been confirmed by RT-PCR in 114 (73.5%) patients. Changes of laboratory tests for rubella without clinical signs of the infection were observed in 20% of contacts. Complex ELISA- and PCR-assisted examination of patients can help to determine the stage of disease and characteristics of immune response. For differential diagnostic of rubella and other infectious diseases with exanthema it is rational to perform complex examination of patients using immunologic and molecular biologic methods.

[Genotyping of rubella virus circulating in Western Siberia of Russia during 2004-2006 epidemic period].

Twenty one strains of rubella virus were isolated in the Western Siberia during 2004-2006 epidemic period. Genotyping of isolated strains was performed by partial sequencing of glycoprotein E1 gene. Phylogenetic analysis showed that 20 out of 21 isolated in the Western Siberia strains of rubella virus belonged to genotype 1g, and 1 strain (isolated in Altai region in 2006)--to genotype 1E.

[Genomic S segment of Crimean-Congo hemorrhagic fever virus circulating in Russia and Bulgaria].

S-segment nucleotide sequences for two Crimean-Congo hemorrhagic fever (CCHF) virus strains isolated in the Rostov Region of Russia and in Bulgaria have been determined. Analysis of complete S-segment nucleotide sequences in the viral strains from different regions of the world has established that the CCHF virus strains isolated from ticks and human beings in different southern Russian regions in 1967 and 2000 are very closely genetically and they form an individual subgroup in the basic European genetic group. By the S-segment structure, the CCHF virus strain isolated in Bulgaria in 1978 belongs to the same genetic group as a representative of its second subgroup. Analysis of the S-segment 3'-noncoding region suggests that the CCHF virus circulating in Europe, Central Asia, and China may have originated from one global focus of infection, including several CCHF virus genovariants. During evolution, fragmental exchange apparently occurred in the S-segment 3'-noncoding region as a result of homological recombination.

[Genetic monitoring of the Crimean-Congo Hemorrhagic Fever virus in Kazakhstan and Tajikistan in 2001-2003].

Blood specimens obtained from 32 CCHF patients were tested for the presence of CCHF virus markers. In addition, 3210 ticks of the genera Hyalomma asiaticum, Hyalomma anatolicum, and Dermacentor niveus were examined to identify the CCHF virus antigen and RNA. This material was obtained during the 2001-2003 local outbreaks of CCHF in Kazakhstan and Tajikistan. The nucleotide sequence in the region 983-1282 of S segment of the CCHF virus for 12 wild type strains was determined. The phylogenetic relationships among the established biovariants of CCHF virus, and also between these biovariants and those from other regions of the world were identified. We were the first to demonstrate the presence of an African-like genotype of CCHF virus in the territory of Kazakhstan. The conclusion was made that two genotypes of CCHF virus were in circulation in Kazakhstan. It was also demonstrated that CCHF virus, circulating in the territories of Kazakhstan and Tajikistan, was genetically heterogeneous.

Complete L segment coding-region sequences of Crimean Congo hemorrhagic fever virus strains from the Russian Federation and Tajikistan.

The large (L) RNA segment of Crimean Congo hemorrhagic fever (CCHF) virus strain AST/TI30908, isolated from pooled Hyalomma marginatum ticks collected in 2002 from the Astrakhan region of European Russia, was amplified piecemeal using reverse-transcription/polymerase chain reaction, followed by direct sequencing of gel-purified amplicons. After removal of 5' and 3' primer-generated termini, the assembled AST/TI30908 L segment sequence is 12112 nucleotides long, with 41.3% G + C content, and is greater than 87% and 96% identical at the nucleotide and translated amino acid levels, respectively, to partial or full-length CCHF virus L segment sequences deposited in GenBank. A complete L segment coding-region sequence for CCHF virus strain TAJ/HU8966, isolated from a patient in Tajikistan in 1990, was determined in a similar fashion. This L segment (12133 nucleotides long, 41.1% G + C content) shares 88% nucleotide identity with the full-length strain Matin from Pakistan, and 97% nucleotide identity with a partial L segment sequence of strain Khodzha from Uzbekistan. Strain TAJ/HU8966 shares at least 96% identity at the translated amino acid level with all other CCHF virus L segment sequences. Although, for the most part, CCHF virus L polyprotein primary sequences are uniformly well conserved, a region of marked variability was identified in the N-terminal half of the RNA-dependent RNA polymerase. This region, approximately 50 amino acids in length, is flanked by previously-reported arenavirus and bunyavirus-conserved regions, and may prove useful in CCHF diagnosis and viral taxonomy.