From preschool to school education: the structure of the emotive environment

AbstractSituations of an emotional pressure on children are investigated in the conditions of transition from preschool to school education. The article defines the structure of the emotive environment of the first grader and shows the differences from the standard model of child's transition from preschool to school education. During this transition the contribution of some components from the group of other emotive situations proves to be equal or even bigger than that of the traditionally important educational and game motivations

Deoxygenation affects composition of membrane-bound proteins in human erythrocytes

Background/Aims: ATP release from erythrocyte plays a key role in hypoxia-induced elevation of blood flow in systematic circulation. We have previously shown that hemolysis contributes to erythrocyte ATP release triggered by several stimuli, including hypoxia, but the molecular mechanisms of hypoxia-increased membrane fragility remain unknown. Methods: In this study, we compared the action of hypoxia on hemolysis, ATP release and the composition of membrane-bound proteins in human erythrocytes. Results: Twenty minutes incubation of human erythrocytes in the oxygen-free environment increased the content of extracellular hemoglobin by ∼1.5 fold. Paired measurements of hemoglobin and ATP content in the same samples, showed a positive correlation between hemolysis and ATP release. Comparative analysis of SDS-PAGE electrophoresis of erythrocyte ghosts obtained under control and deoxygenated conditions revealed a ∼2-fold elevation of the content of membrane-bound protein with Mr of ∼60 kDa. Conclusion: Deoxygenation of human erythrocytes affects composition of membrane-bound proteins. Additional experiments should be performed to identify the molecular origin of 60 kDa protein and its role in the attenuation of erythrocyte integrity and ATP release in hypoxic conditions

Evaluation of fetal absorbed doses from computed tomography examinations of pregnant patients: A systematic review

BACKGROUND: Currently, no systematic data are available on fetal radiation exposure as a result of radiographic studies during pregnancy. Consequently, there are no approved methods of its calculation that can be used in clinical practice. It is especially relevant for computed tomography scans as it is a widely used and highly informative method of diagnostic imaging associated with high exposure levels. AIM: to systematize currently available data on radiation dose absorbed by the fetus from computed tomography scans in pregnant women. MATERIALS AND METHODS: The search for publications in Russian and English was conducted in PubMed/Medline, Google Scholar and еLibrary. The final analysis included 12 papers including 8 studies using human body phantoms, 3 retrospective studies and one prospective clinical study. RESULTS: Abdominal and pelvic computed tomography scans as well as whole-body scans were found to be associated with the highest fetal radiation exposure. However, in none of the publications the fetal exposure limit was exceeded. CONCLUSION: Clinically indicated non-contrast-enhanced computed tomography scans in pregnant women are not likely to be associated with the fetal absorbed doses that exceed the limit of 100 mGy regardless of the scanned area. However, this limit might be exceeded in case of performing multiple studies or if multiphase abdominal or pelvic computed tomography scans, or whole-body computed tomography scans are performed in patients with multiple trauma. In these cases, a decision regarding the need for these investigations should be made by a multi-disciplinary team (including radiation safety specialists, diagnostic radiologists and clinicians) based on the results of additional risk assessment

Effect of C60 filling on structure and properties of composite films based on polystyrene

Both polystyrene films and polystyrene films filled with fullerenes (C60) were fabricated by the solution cast method. Mechanism of fullerene-polystyrene interaction, the structural characteristics of films, and their antimicrobial activity were researched. We found that the polystyrene/fullerene composite films manifest bacteriostatic and fungistatic effect. Keywords: Polystyrene/fullerene composites, X-ray diffraction, IR spectroscopy, Antimicrobial activit

A Single-Turnover Kinetic Study of DNA Demethylation Catalyzed by Fe(II)/α-Ketoglutarate-Dependent Dioxygenase AlkB

AlkB is a Fe(II)/α-ketoglutarate-dependent dioxygenase that repairs some alkylated bases of DNA and RNA in Escherichia coli. In the course of catalysis, oxidation of a co-substrate (α-ketoglutarate, αKG) leads to the formation of a highly reactive ‘oxyferryl’ enzyme-bound intermediate, Fe(IV) = O, ensuring hydroxylation of the alkyl nucleobase adducts. Previous studies have revealed that AlkB is a flexible protein and can adopt different conformations during interactions with cofactors and DNA. To assess the conformational dynamics of the enzyme in complex with single- or double-stranded DNA in real-time mode, we employed the stopped-flow fluorescence method. N1-Methyladenine (m1A) introduced into a sequence of 15-mer oligonucleotides was chosen as the specific damage. Single-turnover kinetics were monitored by means of intrinsic fluorescence of the protein’s Trp residues, fluorescent base analogue 2-aminopurine (2aPu), and a dye–quencher pair (FAM/BHQ1). For all the fluorescent labels, the fluorescent traces showed several phases of consistent conformational changes, which were assigned to specific steps of the enzymatic process. These data offer an overall picture of the structural dynamics of AlkB and DNA during their interaction

Depression in myasthenia gravis: a heterogeneous and intriguing entity

BACKGROUND Depressive symptoms in myasthenia gravis (MG) are common, may mimic other disease features, and contribute to misdiagnosis and diagnostic delay. Nevertheless, the clinical determinants of depressive symptoms in MG remain poorly studied, in particular their overlap with fatigue. Moreover, studies in MG have rarely looked at distinct depression phenotypes. METHODS In 68 consecutive MG patients, we ascertained cognitive-affective and somatic depression with the Beck Depression Inventory (BDI), and also assessed age at disease onset, education, marital state, work ability, sleepiness, fatigue, and treatment modalities. Disease severity was graded according to the Myasthenia Gravis Foundation of America (MGFA) classification. RESULTS The prevalence of moderate-severe depression was 20.5%. While depression and fatigue showed large overlap (n = 37, 54.4%), only fatigue increased with disease severity, while BDI scores did not. Thymectomy was independently associated with lower BDI scores, but had no impact on fatigue. Total BDI scores were similar in patients with predominantly cognitive-affective and with predominantly somatic depression. However, ESS correlated only with cognitive-affective BDI, and younger age was independently associated with cognitive-affective BDI. Conversely, female sex and thymectomy were independently associated with somatic BDI. CONCLUSIONS Depression and fatigue are highly prevalent and largely overlapping comorbidities in MG, but only fatigue increased with disease severity, and only depression was milder in thymectomized patients. Comparative use of BDI subscales in MG reveals distinct depression phenotypes with distinct correlations to other disease features

Effect of the bentonite filler on structure and properties of composites based on hydroxyethyl cellulose

Granulometric test and morphological analysis of the bentonite particles were performed using laser diffraction and low-temperature nitrogen adsorption–desorption techniques. Bentonite particles were immobilized into the hydroxyethyl cellulose matrix by mechanical dispersion, and composite films were obtained. The effect of concentration of the filling agent on structure and tensile properties of composites was revealed. Data on the nature of interaction between hydroxyethyl cellulose and bentonite after the modification of polymer were obtained by IR spectroscopy. It was found that the hydroxyethyl cellulose/bentonite composite films showed an antimicrobial effect against Escherichia coli and Staphylococcus aureus bacteria, as well against fungi association. Keywords: Hydroxyethyl cellulose/bentonite composites, X-ray diffraction, IR spectroscopy, Tensile properties, Antimicrobial activit