Nanostructured silicon nitride thin films for label-free multicolor luminescent cell imaging.

The application of nanostructured luminescent silicon nitride (SiN(X)) thin films for label-free cell imaging is reported for the first time. Different strong local fields ensured by various molecules concentrated in various cell compartments can lead to the creation of preferential electronic conditions for radiative recombination of photogenerated charge carriers via a given electronic channel. Thus, highly contrasted multicolor luminescent cell imaging under one photon excitation becomes possible. The described label-free bio-imaging approach has good compatibility with fluorescence optical microscopy, and allows rapid and efficient cell imaging and cell line recognition.

Charge-driven selective localization of fluorescent nanoparticles in live cells.

Covalent grafting of amino groups onto the carboxylic acid functionalities, naturally covering the surface of fluorescent nanoparticles produced from silicon carbide (SiC NPs), allowed tuning of their surface charge from negative to highly positive. Incubating 3T3-L1 fibroblast cells with differently charged SiC NPs demonstrates the crucial role of the charge in cell fluorescent targeting. Negatively charged SiC NPs concentrate inside the cell nuclei. Close to neutrally charged SiC NPs are present in both cytoplasm and nuclei while positively charged SiC NPs are present only in the cytoplasm and are not able to move inside the nuclei. This effect opens the door for the use of SiC NPs for easy and fast visualization of long-lasting biological processes taking place in the cell cytosol or nucleus as well as providing a new long-term cell imaging tool. Moreover, here we have shown that the interaction between charged NPs and nuclear pore complex plays an essential role in their penetration into the nuclei.

Size tuning of luminescent silicon nanoparticles with meso-porous silicon membranes.

Size tuning of silicon (Si) nanoparticles (NPs) with the use of meso-porous silicon (meso-PS) free-standing layers is reported for the first time. Accumulation of Si NPs inside the membrane pores during the filtering process (NP transport through the meso-PS) leads to an auto-filtration effect (called Si-by-Si (SBS) filtration) allowing more efficient size selection of the NPs. General complex fractal shape and surface chemistry of the whole porous network, layer thickness as well as a given initial NP size dispersion determine final size of the NPs in the filtered solution. Moreover, quantum of step-like NP size increasing equal to 0.12 nm was found.

Strong photoluminescence enhancement of silicon quantum dots by their near-resonant coupling with multi-polar plasmonic hot spots.

Localization of quantum dots (QDs) in the vicinity of metal nanoparticles (NPs) is known as one of the most efficient ways to increase their photoluminescence (PL). Despite the important recent advances achieved in II-VI QDs, only a seven-fold plasmon-induced PL enhancement is reported for Si QDs. In our paper we show that the plasmon-induced strong local PL enhancement of Si QDs in an SiN matrix can reach a 60-fold gain level. This important result was achieved on original tunable "nano-Ag/SiN(X)" plasmonic structures. In particular, we show that (i) localization of Si QDs in hot spot regions created by several randomly arranged Ag NPs and (ii) careful tuning of the multi-polar plasmon bands of Ag NPs to match resonant absorption and emission wavelengths of Si QDs, lead to the important enhancement of their PL intensity.

[Research of imidazo[1,2-a]benzimidazole derivatives. XXX. Synthesis and properties of (imidazo[1,2-a]benzimidazolyl-2)acetic acid derivatives].

Ethyl esters of (9-subtituted-imidazo[1,2-a]benzimidazolyl-2)acetic acids were synthesized. The chemical properties of these esters (hydrolysis, decarboxylation, hydrazinolysis) and biological activity (fungicidal, antimicrobial, antiarrhythmic activity, and also affects on the brain rhythmogenesis) of the prepared compounds were studied.

Monitoring of melamine contamination in fat watery milk by the photoluminescence analysis.

A photoluminescence method to detect the toxic melamine contamination in fat watery milk has been proposed. Despite the quite different luminescence origins of milk and melamine patterns, their wide emission spectra under UV excitation are similar and in the range of 2.2-3.5 eV. The complex milk photoluminescence spectrum composed of riboflavin, furosine, lactulose, Vitamin E and tryptophan emitting species can be modified if milk pattern is undergone by acid treatment (for example, in vinegar). At the same time the melamine emission is not subjected to any modification in vinegar. It allows quantitatively discriminating the melamine contamination in milk in linear range, at least, 0.05-7 g/l from different photoluminescence spectra of milk (water) with and without melamine. Limit of melamine detection achieves 0.01 g/l.

[A promising method of hygienic evaluation of air pollution inside the modules of the international space station by hydrazine derivatives].

The increasing frequency of ISS egress operations resulted in ISS air pollution by an uncharacteristic group of toxic compounds, i. e. propellant residues and products of propellant incomplete burning. High reactivity and toxicity of these compounds necessitated the development of a method of sanitary-chemical evaluation of ISS air safety given penetration of the new pollutants. The method is fulfilled in two stages. First is air sampling and then--sample analysis in ground laboratory by chromatography-mass spectrometry. Air sampling, as well as sample handling and analysis procedures were refined with the use of artificial gas mixtures. The proposed method shows promise as an instrument for the hygienic evaluation of ISS air pollution by hydrazine derivatives.

[Use of inhibitors of the angiotensin-converting enzyme and the beta-adrenoblocker metoprolol combined in treatment of chronic cardiac insufficiency]. / Lechenie khronicheskoi serdechnoi nedostatochnosti ingibitorom angiotenzinprevrashchaiushchego fermenta v sochetanii s beta-blokatorom metoprololom.

Clinical-and-hemodynamic effects were studied of a supplementary use of a selective beta-adrenoblocker metoprolol in an ongoing therapy of chronic cardiac insufficiency (CCI) with inhibitors of the angiotensin-converting enzyme (ACEI) and diuretics. It has been found out that long (over 8 weeks) course of therapy supplemented with metoprolol results in improvement of the left ventricular systolic function and lowering of the functional class. Long-term administration of metoprolol enhances tolerance to a graded physical exercise in CCI patients, which observation is accompanied by a more economic character of its performance. The findings secured validate the expediency of a supplementary use of the beta-adrenoblocker metoprolol in the routine regimen of the supporting treatment of CCI patients involving the use of ACEI plus a diuretic.

[The clinico-hemodynamic effects of losartan in treating patients with chronic heart failure]. / Kliniko-gemodinamicheskie éffekty lozartana pri lechenii bol'nykh s khronicheskoi serdechnoi nedostatochnost'iu.

Clinical and hemodynamic effects were studied of the blockader of AII receptors lozartan in patients with chronic cardiac insufficiency (ChCI). Inclusion of losartan into the conventional therapy of ChCI is accompanied by a lowering of the functional class in patients and improvement of haemodynamic maintenance of the physical exercise performance as evidenced by veloergometry. An 8-week's course of lozartan therapy leads also to a decrease in the anterior-posterior dimensions of the left auricle and an increase in the left ventricular ejection fraction in ChCI patients.

[The antitryptic activity of the blood serum in patients with chronic bronchitis and lung cancer in relation to the phenotypic variant of the alpha-1 proteinase inhibitor]. / Antitripticheskaia aktivnost' syvorotki krovi u bol'nykh khronicheskim bronkhitom i rakom legkikh v zavisimosti ot fenotipicheskogo varianta al'fa-1-ingibitora proteinaz.

Blood serum was studied for its antitryptic activity in 161 patients with chronic bronchitis, 87 individuals with malignant tumors of the respiratory organs, 70 blood donors, with regard to phenotypic variant of alpha 1-inhibitor of proteinases. Difference was revealed in antitryptic activity, associated with the particular features of the pathologic process and phenotypic variant of the inhibitor. There exists in the carriers of homozygote latent insufficiency of the inhibitory defence of the organism against the proteolytic effects.

[The characteristics of the immune status of patients with chronic obstructive bronchitis in PiM phenotypic variants of the alpha 1-proteinase inhibitor]. / Osobennosti immunnogo statusa bol'nykh khronicheskim obstruktivnym bronkhitom pri PiM fenotipicheskikh variantakh al'fa 1-ingibitora proteinaz.

The connection between alpha 1-proteinase inhibitor variants and immunity disorders in patients with chronic obstructive bronchitis is considered in the article. As a result of investigation disorders of both T- and B-immunity systems were found. They consisted in decrease of the content and proliferative activity of T-lymphocytes, changes in their populational composition, dysfunction of B-lymphocytes, dysimmunoglobulinemia. These changes were more pronounced in allele M3+ carriers constituting the risk group on chronic lung diseases.

[Effects of low-energy laser irradiation on blood biochemical parameters in experimental chronic obstructive bronchitis]. / Vozdeistvie nizkoénergeticheskogo lazernogo izlucheniia na biokhimicheskie pokazateli krovi pri éksperimental'nom khronicheskom obstruktivnom bronkhite.

The study established that shifts in oxidant-antioxidant system induced by chronic obstructive bronchitis are correctable by He-Ne laser irradiation. This conclusion was based on biochemical indices of the blood measured in experimental animals: lipid peroxidation, general antitryptic activity of the serum, activity of the enzymes superoxide dismutase, gamma-glutamyl transferase, pseudocholine esterase, alpha-oxybutyrate dehydrogenase, glucose 6-phosphate dehydrogenase.

[Glucose-6-phosphate dehydrogenase activity in patients with chronic inflammatory lung diseases]. / Aktivnost' gliukozo-6-fosfatdegidrogenazy u bol'nykh khronicheskimi vospalitel'nymi zabolevaniiami legkikh.

The activity of the key enzyme of the pentoso-phosphate cycle--glucoso-6-phosphatedehydrogenase was examined in patients with chronic inflammatory pulmonary diseases. Results indicate that with exacerbation of the process in the bronchopulmonary system there occurs an increase of the activity of the mentioned enzyme. Examination of the activity of this enzyme may be of value for optimization of treatment measures in patients with inflammatory pulmonary diseases.

[Cellular and humoral immunity in patients with chronic bronchitis and hereditary variants of alpha 1-proteinase inhibitor]. / Sostoianie kletochnogo i gumoral'nogo immuniteta u bol'nykh khronicheskim bronkhitom s nasledstvennymi variantami al'fa 1-ingibitora proteinaz.

Cellular and humoral immunity was investigated in practically healthy subjects with PLM allele subtypes in the homozygotic form, PiM3M3 phenotypical variants and normal phenotypical variant PiM1M1 in the presence of which practically healthy subjects show a 100% antitryptic activity in the blood serum. A study of the immunological reactivity of 225 patients with chronic obstructive bronchitis revealed in these patients disorders of the cellular and humoral immunity and they were more pronounced in patients with PiM3M3 phenotypical variant.