Induction of Crystallization of Calcium Oxalate Dihydrate in Micellar Solutions of Anionic Surfactants

Calcium oxalate dihydrate (CaC2O4.(2+x)H2O; COD; x ≤ 0.5) does not readily crystallize from electrolytic solutions but appears as a component in crystalluria. In this paper, we review in vitro studies on the factors responsible for its nucleation and growth with special attention given to the role of surfactants. The following surfactants were tested: dodecyl ammonium chloride (cationic), octaethylene monohexadecylether (non-ionic), sodium dodecyl sulfate (SOS, anionic), dioctyl sulphosuccinate (AOT, anionic), and sodium cholate (NaC, anionic). The cationic and some of the anionic surfactants (SOS, AOT) induced different habit modifications of growing calcium oxalate crystals by preferential adsorption at different crystal faces. In addition, the anionic surfactants effectively induced crystallization of COD at the expense of COM, the proportion of COD in the precipitates abruptly increasing above a critical surfactant concentration, close to, but not necessarily identical with the respective CMC. A mechanism is proposed, whereby crystallization of COD in the presence of surfactants is a consequence of the inhibition of COM by preferential adsorption of surfactant hemimicelles (two-dimensional surface aggregates) at the surfaces of growing crystals

HYPOPARATHYROIDISM: MODERN CONCEPTS AND ANALYSIS OF A CLINICAL CASE

The article deals with modern concepts of etiopathogenesis, clinic, diagnosis and treatment of hypoparathyroidism. Pathophysiological mechanisms of clinical symptoms are described. The paper contains the analyzis of autoimmune hypoparathyroidism clinical case

Automatic correction of hand pointing in stereoscopic depth

In order to examine whether stereoscopic depth information could drive fast automatic correction of hand pointing, an experiment was designed in a 3D visual environment in which participants were asked to point to a target at different stereoscopic depths as quickly and accurately as possible within a limited time window (≤300 ms). The experiment consisted of two tasks: "depthGO" in which participants were asked to point to the new target position if the target jumped, and "depthSTOP" in which participants were instructed to abort their ongoing movements after the target jumped. The depth jump was designed to occur in 20% of the trials in both tasks. Results showed that fast automatic correction of hand movements could be driven by stereoscopic depth to occur in as early as 190 ms.This work was supported by the Grants from the National Natural Science Foundation of China (60970062 and 61173116) and the Doctoral Fund of Ministry of Education of China (20110072110014)

TO HANTAVIRUS INFECTION IN PEOPLE AND SMALL MAMMALS IN BAIKAL AREA

The article describes the results of recognaissance surveys of blood serums of humans in Baikal area for hantavirus antibodies and of tissue specimens (lungs) of small mammal for hantavirus antigens. This investigation demonstrated that Baikal area inhabitants contact such dangerous pathogens as hantaviruses. It's proved by the presence of hantavirus antibodies in human serum samples. IgG or IgM antibodies to hantaviruses were found in 3,7 % of 379 tested serum samples. IgM were found in 1,6 % of cases, IgG - in 2,1 % of cases. 2 patients with IgG and IgM with suspected traces of hantavirus infection had complaints to hyperthermia (up to 40,5 °C) and wasting. Blood serums with positive results of hantavirus antibodies were found in residents of Irkutsk region. Hantavirus antigens weren't found in researched lung samples of mouse-like rodent and insectivores from Angarsk, Irkutsk, Zalari and Ust-Kut districts of Irkutsk region and Tunkinsky district of Republic of Buryatia

Response sensitivity to bacteriophages of Staphylococcus aureus strains isolated from the microbiota of the oropharynx in children of Irkutsk

Dysbiotic disorders of the oropharynx takes one of the first places in the structure of morbidity worldwide. The aim of the study was to determine the peculiarities of microbiocenosis of the oropharynx in children at different ages and to assess the level of sensitivity of S. aureus strains to specific bacteriophages. Material for the study consisted of 84 smears from the oropharynx of children with inflammatory diseases of the upper respiratory tract (nasopharyngitis, pharyngitis, tonsillitis, laryngitis (J00, J02, J03, J04 according to 1CD-10). The biological material was distributed depending on the age of the surveyed: the first group - children 3-6 years (n = 61) and the second age group - children 7-12 years (n = 23). Studies of the microflora of the oropharynx were performed according to standard methods. Isolated microorganisms were identified by morphological, tinctorial, cultural and biochemical properties. The results were evaluated in accordance with the Order of USSR Ministry of Health N 535 as of April 22,1985. Specific lytic activity of bacteriophages against S. aureus was determined using preparations of staphylococcal bacteriophage and polyvalent pyobacteriophage Sexta. The sensitivity of strains of S. aureus to specific bacteriophages was assessed by the method of «crosses», according to the guidelines. Statistical analysis was performed with the use of licensed applications Offiœ Ms Excel 2007for Windows 7 BioStat v. 5.0.1.2008. Correlation analysis (Pearson method) was used. 1t has been shown that with increasing age children in the oropharynx microbial density is increasing for indicators of both normoflora (S. oralis), and of opportunistic microflora (S. β-hemolytic, S. pyogenes, S. pneumoniae, bacteria Enterobacteriaceae), especially of S. aureus (up to 74 %). Registration of sensitive strains of S. aureus in more than 70 % of cases in preschool and school-aged children is evidence of the correctness of correction of the dysbiotic disorders of the oropharynx with the use of bacteriophages of staphylococcus and Sexta

Predicting the solvation of organic compounds in aqueous environments: from alkanes and alcohols to pharmaceuticals

The development of accurate models to predict the solvation, solubility, and partitioning of nonpolar and amphiphilic compounds in aqueous environments remains an important challenge. We develop state-of-the-art group-interaction models that deliver an accurate description of the thermodynamic properties of alkanes and alcohols in aqueous solution. The group-contribution formulation of the statistical associating fluid theory based on potentials with a variable Mie form (SAFT-γ Mie) is shown to provide accurate predictions of the phase equilibria, including liquid–liquid equilibria, solubility, free energies of solvation, and other infinite-dilution properties. The transferability of the model is further exemplified with predictions of octanol–water partitioning and solubility for a range of organic and pharmaceutically relevant compounds. Our SAFT-γ Mie platform is reliable for the prediction of challenging properties such as mutual solubilities of water and organic compounds which can span over 10 orders of magnitude, while remaining generic in its applicability to a wide range of compounds and thermodynamic conditions. Our work sheds light on contradictory findings related to alkane–water solubility data and the suitability of models that do not account explicitly for polarity

The Effect of Keyboard-Based Word Processing on Students With Different Working Memory Capacity During the Process of Academic Writing

This study addresses the current debate about the beneficial effects of text processing software on students with different working memory (WM) during the process of academic writing, especially with regard to the ability to display higher-level conceptual thinking. A total of 54 graduate students (15 male, 39 female) wrote one essay by hand and one by keyboard. Our results show a beneficial effect of text processing software, in terms of both the qualitative and quantitative writing output. A hierarchical cluster analysis was used to detect distinct performance groups in the sample. These performance groups mapped onto three differing working memory profiles. The groups with higher mean WM scores manifested superior writing complexity using a keyboard, in contrast to the cluster with the lowest mean WM. The results also point out that more revision during the writing process itself does not inevitably reduce the quality of the final output

Luminescence Solvato- and Vapochromism of Alkynyl-Phosphine Copper Clusters

The reaction of [Cu(NCMe)4][PF6] with aromatic acetylenes HC2R and triphosphine 1,1,1-tris(diphenylphosphino)methane in the presence of NEt3 results in the formation of hexanuclear Cu(I) clusters with the general formula [Cu6(C2R)4{(PPh2)3CH}2][PF6]2 (R = 4-X-C6H4 (1-5) and C5H4N (6); X = NMe2 (1), OMe (2), H (3), Ph (4), CF3 (5)). The structural motif of the complexes studied consists of a Cu6 metal core supported by two phosphine ligands and stabilized by σ- and π-coordination of the alkynyl fragments (together with coordination of pyridine nitrogen atoms in cluster 6). The solid state structures of complexes 2-6 were determined by single crystal XRD analysis. The structures of the complexes in solution were elucidated by (1)H, (31)P, (1)H-(1)H COSY NMR spectroscopy, and ESI mass spectrometry. Clusters 1-6 exhibit moderately strong phosphorescence in the solid state with quantum yields up to 17%. Complexes 1-5 were found to form solvates (acetone, acetonitrile) in the solid state. The coordination of loosely bound solvent molecules strongly affects emission characteristics and leads to solvato- and vapochromic behavior of the clusters. Thus, solvent-free and acetonitrile solvated forms of 3 demonstrate contrasting emission in orange (615 nm) and blue (475 nm) regions, respectively. The computational studies show that alkynyl-centered IL transitions mixed with those of MLCT between the Cu6 metal core and the ligand environment play a dominant role in the formation of excited states and can be considerably modulated by weakly coordinating solvent molecules leading to luminescence vapochromism.This research has been supported by St. Petersburg State University Research Grant 0.37.169.2014, and Russian Foundation for Basic Research Grants 13-03-00970, 14-03-32077, and 13-03-12411. Academy of Finland (Grant 268993/2013, I.O.K), University of Eastern Finland (strategic funding—Russian–Finnish collaborative project), is also gratefully acknowledged. The work was carried out using equipment of the Analytical Center of Nano- and Biotechnologies of SPbSPU with financial support of the Ministry of Education and Science of Russian Federation; Centers for Magnetic Resonance, X-ray Diffraction Studies, Chemical Analysis and Materials Research, Optical and Laser Materials Research; and Computer Center of St. Petersburg State University

THE PREVALENCE OF TICK-BORNE ENCEPHALITIS VIRUS ANTIGEN IN SERUM SAMPLES FROM PEOPLE SUFFERED FROM TICK BITES

The information about more than 17 thousand cases of public inquiries to the Center of Diagnostics and prevention of tick-borne infections of Scientific Center of Problems Family and Human Reproduction Problems because of bites of ticks at the territory of Irkutsk Region during the last six years (2007-2012) is analyzed in the article. All age groups undergo to the bites of ticks. Over the half of the people asking for help have the policy of voluntary health insurance of "Anti tick" kind. The percentage of people vaccinated against the tick borne encephalitis is a little bit over than 8 % what proves the low level of the sanitary education and neglect to the human health in the region. Every year the cases of tick's bites and findings of tick-borne encephalitis virus antigen in blood serum of bitten people in the northern areas of Irkutsk region are revealed. Every year in average 90 examples of blood serum had tick-borne encephalitis virus antigen that means 3 % of bitten people have pre-clinical infection of tick-borne encephalitis. Patients with positive result of tick-borne encephalitis virus antigen (543 patients) had the necessary consultation and preventive treatment with specific immunoglobulin according to the instruction of application. Diseases of tick-borne encephalitis among the patients had the preventive treatment in time were not marked