Valence tautomeric transition of bis(o-dioxolene) cobalt complex in solid state and solution.

Valence tautomer transition occurs mainly in 3d metalorganic complexes with redox-active ligands and makes them potential candidates for single-molecular switches. The transition occurs under temperature, pressure, or light-induced stimuli and is strongly affected by the intermolecular interactions. However single-crystal x-ray diffraction is not always applicable to such systems when crystal structure is destroyed upon transition or system is studied in the solution. Such an example is bis(o-semiquinonato) cobalt complex with TEMPO-functionalized iminopyridine ancillary ligand. In this work we apply two complementary techniques-ligand-sensitive Fourier transform infrared spectroscopy (FTIR) and metal sensitive Co K-edge x-ray absorption spectroscopy (XAS). In a solid state, a temperature hysteresis of magnetization larger than 40 K was observed upon cyclic cooling-heating. So, the temperature of phase transition upon cooling is about 40 K lower than that upon heating. In solution, the x-ray absorption spectra for high-temperature and low-temperature states were similar to that in the solid form, but the hysteresis was absent. Two methods are can probe valence tautomer transition, but XAS has an advantage for the liquid phase analysis and FTIR has larger sensitivity to the ligand related interactions in solid.

Photocyclization of diarylethenes: the effect of imidazole on the oxidative photodegradation process.

We have studied the photoreaction of 1,2-diarylethenes under aerobic conditions in the presence of various amines to prevent side processes promoted by singlet oxygen. It has been found that the most amines quite effectively deactivate processes associated with singlet oxygen, but primary and secondary amines unlike tertiary ones, react with substrates resulting in various side products. Among the studied amines, the most effective additive for preventing side processes, including those associated with singlet oxygen is imidazole, which is practically not consumed in photoreaction. It was shown that imidazole can also prevents the photodegradation of organic photochromes in solutions. The results obtained can be used in various branches of science, technology and medicine to improve the photostability of photosensitive organics (dyes).

Operando XAS and UV-Vis Characterization of the Photodynamic Spiropyran-Zinc Complexes.

Thermal and photoinduced processes accompanying complexation of photochromic spiropyrans (SPP) with Zn ions in acetone solution were characterized by means of UV-vis and X-ray absorption spectroscopies in operando regime. SPP ligands are usually transparent at λ > 350 nm, but after mixing with Zn ions, they produce a stable colored (ε = 32 000-38 000 M-1 cm-1) complex with maximum absorption at 525 nm, which makes them a powerful tool for monitoring metal-ion concentration in solution. The complex revealed fluorescence and photochromic behavior under static irradiation with visible light with constant photoreaction quantum yield across its characteristic absorption band. Zn K-edge X-ray absorption spectra show prominent changes in Zn local atomic structure between free Zn ions and Zn complex. The pump-flow-probe scheme was adapted to measure operando changes in Zn coordination upon light irradiation. Within experimental time resolution, we have determined that 20 µs after light irradiation, Zn ion is released out of the complex. This is the first example of the direct spectroscopic probe of the Zn photorelease from the spiropyran complex.

Tetrodotoxin and its analogues profile in nemertean species from the sea of Japan.

For the first time search for tetrodotoxin (TTX) and its analogues in the extracts of nemerteans using HPLC-MS/MS was performed. TTX analogues were detected in two nemertean species in addition to TTX: 7 analogues were detected in the extract of Cephalothrix simula, 3 analogues - in the extract 11-norTTX of Kulikovia manchenkoi. Presence of 5-deoxyTTX, 11-deoxyTTX, 5,6,11-trideoxyTTX and -6(R)-ol in nemerteans was shown for the first time.

[Optimization of the algorithm for the detection and the differential non-pharmacological correction of the risk factors and the preclinical stages of atherosclerosis at the level of the health resort-based primary care]. / Optimizatsiia algoritma vyiavleniia i differentsirovannoi nemedikamentoznoi korrektsii faktorov riska i doklinicheskikh stadii ateroskleroza v pervichnom zvene zdravookhraneniia na kurorte.

This article presents the results of a comparative prospective study of 276 subjects at the age between 40 and 65 years presenting with risk factors (RF) of atherosclerosis and its preclinical stages (APC). All of them were reckoned to be at a moderate risk of developing APC based on the results of evaluation with the use of the SCORE scale which implied the necessity of their differential non-pharmacological treatment during a two-year period with the application of a variety of preventive therapeutic strategies. The patients were allocated to three different (initially comparable) groups. The main group (group 1) was comprised of 98 subjects who received the optimized combined treatment including climatotherapy, dietary therapy, psychotherapy, hydrotherapy, physiotherapy, and hypoxytherapy; in addition, they were involved in the program of therapeutic physical exercises and in the educational program. The group of comparison (group 2) consisted of 88 subjects who were advised to withstand pernicious habits, to keep to the prescribed diet, and intensify the physical activity. The subjects included in the control group 3 were given no preventive treatment whatsoever. The optimized system for the early diagnostics and identification of the risk factors and/or ACD was employed for examining the members of group 1. By the end of the study, risk factors of atherosclerosis and APC were documented in 86.2% and 76.6% of the patients of group 1, respectively. The number of disability days averaged 7.2 per person versus 16.3 and 22.6 in comparison and control groups, respectively. There were no newly diagnosed cases of cardiovascular diseases (CVD) over the study period among the patients of group 1, in contrast to 11.4% and 25.6% such cases in groups 2 and 3, respectively. The results of this study give evidence that the optimized strategy of non-pharmacological correction of the risk factors and the preclinical stages of atherosclerosis at the level of the health resort-based primary care has advantages over the standard therapy because it makes it possible to reduce the frequency of development of new cases of cardiovascular diseases and to decrease the disability rate. It is concluded that the proposed approach enhances the effectiveness of primary prophylaxis of cardiovascular diseases associated with atherosclerosis and relieves the burden of this pathology. It can therefore be recommended for the more extensive application at the level of the health resort-based primary care settings.

Advanced consumable-free morphological analysis of intact red blood cells by a compact scanning flow cytometer.

Whereas modern automated blood cell analyzers measure the volume of individual red blood cells (RBCs), leading to four RBC indices (mean corpuscular volume, MCV; mean corpuscular hemoglobin, MCH; mean corpuscular hemoglobin concentration, MCHC; red cell distribution width, and RDW), the RBC shape has not been assessed by clinical screening tools. We applied the scanning flow cytometer (SFC) for complete characterization of intact RBC morphology in terms of diameter, maximal and minimal thicknesses, volume, surface area, sphericity index, spontaneous curvature, hemoglobin concentration, and content. The above-mentioned individual RBC characteristics were measured without fluorescent markers and other chemicals by a SFC equipped only with 660 nm laser for RBC illumination and single detector for measurement of angle-resolved light scattering. The distributions over all RBC characteristics were constructed and processed statistically to form the novel 31 RBC indices for 22 donor samples. Our results confirm the possibility of precise, label-free, enhanced morphological analysis of individual intact RBCs with compact single-detector flow cytometer. Detailed characterization of RBCs with high statistics and precision can be used to increase the value of screening examinations and to reveal pathologies accompanied by abnormality of RBC shape. © 2017 International Society for Advancement of Cytometry.

Fluorescence-free flow cytometry for measurement of shape index distribution of resting, partially activated, and fully activated platelets.

Whereas commercially available hematological analyzers measure volume of individual platelets, angle-resolved light-scattering provides unique ability to additionally measure their shape index. We utilized the scanning flow cytometer to measure light-scattering profiles (LSPs) of individual platelets taken from 16 healthy donors and the solution of the inverse light-scattering problem to retrieve the volume and shape index of each platelet. In normal conditions, the platelet shape index distribution (PSID) demonstrates three peaks, which relate to resting, partially activated, and fully activated platelets. We developed an algorithm, based on fitting PSID by a sum of three peak functions, to determine the percentage, mean platelet shape index, and distribution width of each platelet fraction. In total, this method gives eight additional parameters of platelet morphology and function to be used in clinical hematological analysis. We also stimulated the platelets with adenosine diphosphate (ADP) and measured the dependence of equilibrium PSID, including the total percentage of activated platelets, on ADP concentration. © 2016 International Society for Advancement of Cytometry.

Dynamic quantification of antigen molecules with flow cytometry.

Traditional methods for estimating the number of expressed molecules, based on the detection of target antigens bound with fluorescently labeled antibodies, assume that the antigen-antibody reaction reaches equilibrium. A calibration procedure is used to convert the intensity of the fluorescence signal to the number of target molecules. Along with the different limitations of every calibration system, this substantially limits the applicability of the traditional approaches especially in the case of low affinity antibodies. We address this problem here with studies in which we demonstrate a new approach to the antigen molecule quantification problem. Instead of using a static calibration system, we analyzed mean fluorescence values over time by flow cytometry during antibody-antigen binding. Experimental data obtained with an LSRII cytometer were fitted by a diffusion-reaction mathematical model using the Levenberg-Marquardt nonlinear least squares curve-fitting algorithm in order to obtain the number of target antigen molecules per cell. Results were compared with the Quanti-BRITE calibration system. We conclude that, instead of using experiment-specific calibration, the value of the binding rate constant for each particular antibody-antigen reaction can be used to quantify antigen molecules with flow cytometry. The radius of CD8 antibody molecule binding site was found, that allows recalculating the binding rate constant for other conditions (different sizes of reagent molecules, fluorescent label, medium viscosity and temperature). This approach is independent of specially prepared calibration beads, antibody reagents and the specific dye and can be applied to both low and high affinity antibodies, under both saturating and non-saturating binding conditions. The method was demonstrated on a human blood sample dataset investigating CD8α antigen on T cells in stable binding conditions.

Dynamic quantification of antigen molecules with flow cytometry.

Traditional methods for estimating the number of expressed molecules, based on the detection of target antigens bound with fluorescently labeled antibodies, assume that the antigen-antibody reaction reaches equilibrium. A calibration procedure is used to convert the intensity of the fluorescence signal to the number of target molecules. Along with the different limitations of every calibration system, this substantially limits the applicability of the traditional approaches especially in the case of low affinity antibodies. We address this problem here with studies in which we demonstrate a new approach to the antigen molecule quantification problem. Instead of using a static calibration system, we analyzed mean fluorescence values over time by flow cytometry during antibody-antigen binding. Experimental data obtained with an LSRII cytometer were fitted by a diffusion-reaction mathematical model using the Levenberg-Marquardt nonlinear least squares curve-fitting algorithm in order to obtain the number of target antigen molecules per cell. Results were compared with the Quanti-BRITE calibration system. We conclude that, instead of using experiment-specific calibration, the value of the binding rate constant for each particular antibody-antigen reaction can be used to quantify antigen molecules with flow cytometry. The radius of CD8 antibody molecule binding site was found, that allows recalculating the binding rate constant for other conditions (different sizes of reagent molecules, fluorescent label, medium viscosity and temperature). This approach is independent of specially prepared calibration beads, antibody reagents and the specific dye and can be applied to both low and high affinity antibodies, under both saturating and non-saturating binding conditions. The method was demonstrated on a human blood sample dataset investigating CD8α antigen on T cells in stable binding conditions.

[Early diagnostics, prophylaxis, and non-pharmacological treatment of the preclinical stages of atherosclerosis and arterial hypertension].

Cardiovascular diseases remain the leading cause of death in most countries, including Russia. Non-pharmacological-modalities intended for the primary prevention of cardiovascular disease including hypertension and atherosclerosis currently acquire special significance. The objective of the present*study was to develop a system of methods for early diagnostics, prevention and treatment of the preclinical stages of atherosclerosis and hypertension Another objective was to estimate the effectiveness of these methods. A total of 310 patients at risk-of arterial hypertension and atherosclerosis or with pre-clinical stages of these conditions were examined during a two year observation period. The system of early diagnosis and non-pharmacological primary prevention of cardiovascular disease was developed and evaluated using climatotherapeutic and physiotherapeutic methods in combination with and personalized dietary therapy, hypoxic-hypercapnic factors and educational programs. The study has demonstrated that the proposed system allowed to significantly (p < 0.05) reduce cardiovascular morbidity. The patients of the main group experienced the reduction of abdominal obesity and blood pressure along with the improvement of the blood lipid profile and other indicators. These parameters remained unaltered in the patients comprising the control group. In the main group, the incidence of coronary heart disease and hypertension was 62.5% and 81.25% lower respectively than in the control group.

[Nucleus DNA content measurement methods features].

We suggest a new theoretical method of the flow cytometry DNA histograms and apply it for Drosophila melanogaster imaginal discs cells. The model gives a possibility to determine the proportions of cells in G1, G2 (M) and S cell cycle phases. We show that the precision of G1 and G2 (M) DNA content measurements is limited by the precision of device zero signal arrangement. The usage of calculated device zero and dividing cells as the DNA content standards may improve the precision of DNA content measurements. We also compared the precisions of different DNA content methods and draw the conclusion that the current precisions of different methods are similar and lie within 2-6% interval.

[Optimization of the-spa-and-resort treatment of the patients with metabolic syndrome].

The present study included 271 patients presenting with metabolic syndrome. It was designed to compare the efficacy of traditional and optimized therapeutic modalities for the management of this condition. The modified treatment program included climatotherapy, dietary therapy, physical exercises, hydro-balneotherapy, hypoxic hyperkapnotherapy, and education. The study demonstrated that the proposed therapeutic program increased the efficiency of the spa-and-resort treatment.

[Sanatorium and spa treatment of patients with isolated and combined pathology of the cardiovascular system and metabolism].

The present study involved 720 patients with metabolic syndrome, diabetes mellitus, coronary heart disease, hypertensive disease, and various combinations of these conditions examined in the course of sanatorium and spa treatment. The patients received either traditional or modified therapy. The latter modality included climato-balneotherapy, hypoxytherapy, bioresonance therapy, and hypercapnotherapy supplemented by the intake of Arfazetin herbal tea, Magnerot tablets, and Chvizhepse mineral water. Results of the study indicate that the proposed combined treatment had more pronounced curative effect compared with traditional therapy in patients of all groups included in this study.

Genetic determinants of the efficiency of climatotherapy in patients with chronic heart failure.

We studied the dependence of climatotherapy effectiveness in patients with chronic heart failure (functional classes 0-II) on Ca(2+)-ATPase, phospholamban, beta1-adrenoceptor, and insulin-like growth factor 1 gene polymorphisms and possible interaction of these genes during the realization of the effect of climatotherapy. The effectiveness of climatotherapy depended on polymorphism of the studied genes; the maximum effect was attained in patients with the GG polymorphism of the Ca(2+)-ATPase gene, GT polymorphism of the phospholamban gene, ArgGly polymorphism of the beta1-adrenoceptor gene, and 19/19 polymorphism of the insulin-like growth factor 1 gene. We demonstrated additive interaction of Ca(2+)-ATPase and beta1-adrenoceptor genes during the realization of the cardiotonic effect of climatotherapy.

Experimental study of the heat transport processes in dusty plasma fluid.

The results are given of an experimental investigation of heat transport processes in fluid dusty structures in rf-discharge plasmas under different conditions: for discharge in argon, and for discharge in air under an action of electron beam. The analysis of steady-state and unsteady-state heat transfer is used to obtain the coefficients of thermal conductivity and thermal diffusivity under the assumption that the observed heat transport is associated with a thermal conduction in the dusty component of plasmas. The temperature dependence of these coefficients is obtained, which agrees qualitatively with the results of numerical simulation for simple monatomic liquids.