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The self-assembly of peptides is a key direction for fabrication of advanced materials. Novel approaches for fine tuning of macroscopic and microscopic properties of peptide self-assemblies are of a high demand for constructing biomaterials with desired properties. In this work, while studying the kinetics of the Fmoc-Diphenylalanine (Fmoc-FF) dipeptide self-assembly using the Thioflavin T (ThT) dye, we observed that the presence of ThT strongly modifies structural and mechanical properties of the Fmoc-FF hydrogel. Notably, the presence of ThT resulted in a tenfold increase of the gelation time and in the formation of short and dense fibers in the hydrogel. As a result of these morphological alteration higher thermal stability, and, most important, tenfold increase of the hydrogel rigidity was achieved. Hence, ThT not only slowed the kinetics of the Fmoc-FF hydrogel formation, but also strongly enhanced its mechanical properties. In this study, we provide a detailed description of the ThT effect on the hydrogel properties and suggest the mechanisms for this phenomenon, paving the way for the novel approach to the control of the peptide hydrogels' micro- and macroscale properties.

Biochemical adaptations of energy metabolism and some pathways of glucose oxidation during a change in salinity of the environment in larvae and smolts of the pink salmonOncorhynchus gorbuscha(Walb.) inhabiting the White Sea were studied. We assayed the activity of energy and carbohydrate metabolism enzymes (cytochromecoxidase (COХ), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PDH), 1-glycerophosphate dehydrogenase (1-GPDH), and aldolase) in pink salmon larvae in a short-term aquarium experiment and in pink salmon smolts in a long-term cage experiment simulating the transition of juveniles from freshwater to a marine environment. A decrease in the activity of COX, LDH, 1‑GPDH, and aldolase already in the first hour after the transfer of larvae to seawater was shown. Smolts kept in the estuary and in the sea had low levels of activity of 1-GPDH and aldolase in comparison with individuals from the river. Most likely, in the salmon juveniles studied, there was a redistribution of carbohydrates between the reactions of aerobic and anaerobic metabolism in favor of anaerobic ATP synthesis. No changes in the enzyme activity of the pentose phosphate pathway, G-6-PDH, were found in either larvae or smolts compared with the individuals kept in freshwater. Maintenance of the required levels of anaerobic metabolism and of the pentose phosphate pathway is probably one of the mechanisms of biochemical adaptation of pink salmon to changes in salinity.

In the crystal of [(2-MeO)(5-Cl)C6H3]3Bi (I), obtained from bismuth trichloride and 2-methoxy-5-chlorophenyllithium in ether, bismuth atoms have a trigonal ligand environment. The coordination number of the central atom is 6 (3 + 3), with allowance made for the coordination of the MeO oxygen atom to the metal (the Bi···OMe intramolecular distances are 3.014(6), 3.088(6), and 3.168(6) A). Treatment of a mixture of I and bromodifluoroacetic acid, or [(2-MeO)(5-Br)C6H3]3Bi and 2,3,4,5-tetrafluorobenzoic acid in ether with tert-butyl hydroperoxide results in the formation of trigonal bipyramidal triarylbismuth dicarboxylates [(2-MeO)(5-Cl)C6H3]3Bi[OC(O)CF2Br]2 (II) and [(2-MeO)(5-Br)C6H3]3Bi[OC(O)C6HF4-2,3,4,5]2 (III), respectively, with carboxyl ligands in the apical positions. In the crystals of II and III, the metal atom is additionally coordinated to the oxygen atoms of the O=C and MeO groups (3.05(16), 3.30(16), and 3.153(5)−3.117(5) A for II and 3.004(7), 3.230(7), and 3.159(7)−3.199(7) A for III). The structures of I–III were studied by X-ray diffraction (CIF file CCDC nos. 2044006 (I), 2044005 (II), and 2048153 (III)).

Modeling the flow and level of prostaglandins in open systems under the action of prostaglandin H synthase (PGHS) inhibitors (nonsteroidal anti-inflammatory drugs, NSAIDs) was carried out. These open systems included a steady PGHS input, fast inactivation of PGHS during the reaction, degradation of all PGHS forms, conversion of prostaglandin (PG) to biologically inactive substances, and various types of delivery of inhibitors and substrate (arachidonic acid, AA). A slow reversible inhibitor of PGHS (indomethacin) and a slow irreversible inhibitor of PGHS (aspirin) were considered as inhibitors. The explicit analytical expressions for flows and concentrations in steady state and transient mode were obtained. In steady state the dependences of flow and level of PG on the concentration of AA were described by the Michaelis–Menten-type equation. The values of the maximum flows, maximum levels, and Michaelis constant in these equations are inversely proportional to the constant of inactivation of the enzyme during the reaction. In the closed systems, slow PGHS inhibitors are manifested as non-competitive with respect to AA, but in open systems, their behavior is fully competitive with respect to AA, so the presence of inhibitor increases the range of changes of PG level under the change of AA concentration. The reversible inhibitor (indomethacin), in contrast to the irreversible inhibitor (aspirin), in transient mode has been shown to manifest itself as the repository for the active enzyme because of the formation of enzyme-inhibitory complexes. The system disturbance under the rapid increase of indomethacin concentration leads to the biphasic change of the PG level: after the initial rapid decrease it increases gradually to the new steady state. In the presence of indomethacin, the system disturbance under the rapid increase of AA concentration leads to the release of the enzyme from enzyme-inhibitory complexes, and the PG level for a certain period significantly increases compared with the absence of inhibitor. The results of modeling of the regulation of the level of prostaglandins in different states of the open systems undoubtedly need to be used in the study of NSAIDs in vivo.

This paper reports a process for the growth of zinc–erbium codoped lithium niobate single crystals using a growth charge synthesized from a Nb2O5:Zn:Er precursor and Li2CO3. Characterization of the LiNbO3:Zn:Er crystals by high-speed evaluation of the number of scattering centers, piezoacoustic measurements, photoinduced light scattering, and laser conoscopy has demonstrated that they have high optical quality. The proposed technological approaches are aimed at designing functional materials with fundamentally new characteristics for electronics, acoustoelectronics, and integrated, quantum, and laser optics.

The main problems associated with the operation of reverse osmosis facilities in the treatment of groundwater for drinking water are considered and the possibilities of reducing the concentrate consumption are studied. The existing solutions for reducing the consumption of concentrate using reagent and evaporation techniques are described. The presented article is devoted to the investigation of possibilities to remove calcium carbonate from concentrate due to calcium deposition on “seed” crystals. A new technique for reducing concentrate flow is presented that consists of the operation of a membrane unit in circulation mode whereby concentrate is circulated through a “seed” reactor. Calcium and carbonate ions deposit on the seed crystals thus reducing the scaling hazard and total dissolved solid (TDS) value. A water treatment flow diagram is presented and technical parameters of membrane facilities are determined at each stage that allow one to calculate the entire technological scheme. The product flow on each membrane stage is calculated, scaling rates and calcium carbonate deposition rates are evaluated; caustic consumption and number of membrane facilities at each stage are determined. An experimental technique to determine the amount of hardness removed from the concentrate and the minimal volume of concentrate that could be reached per day is described. The main dependences are obtained and presented, which make it possible to determine the costs of electricity and reagents, types of membranes and volumes of concentrate, the rates of accumulation of sediment on the membranes, and the efficiency of removing hardness ions from water during the operation of the third-stage setup in the circulation mode.

The reactions of tris(para-tolyl)antimony (4-МеС6H4)3Sb with chloroacetic acid and of triphenylantimony Ph3Sb with 3,4,5-trifluorobenzoic and 2,3-difluorobenzoic acids in the presence of tert-butyl hydroperoxide afford triarylantimony dicarboxylates Ar3Sb[OC(O)R]2, where Ar = p-Tol, R = CH2Cl (I), Ar = Ph, C6H2F3-3,4,5 (II), and C6H3F2-2,3 (III). According to the X-ray diffraction data (CIF files CCDC nos. 1883320 (I), 1979844 (II), and 1980334 (III)), the Sb atoms in compounds I−III have the coordination of a trigonal bipyramid. The OSbO axial angles are 174.47(6)° (I), 173.98(7)° (II), and 175.98(6)° (III). The Sb−O and Sb−С bond lengths are 2.145(2), 2.143(2), and 2.104(2)–2.109(2) A in compound I; 2.121(2), 2.121(2) and 2.098(2)–2.112(3) A in compound II; and 2.1302(18), 2.1132(18), and 2.109(3)–2.117(3) A in compound III. The intramolecular Sb⋅⋅⋅O distances with the carbonyl oxygen atom (3.054(3) and 3.080(3) A (I), 3.033 A (II), and 2.959(3) and 3.054(2) A (III)) are less than the sum of the van der Waals radii of Sb and O. The structural organization of the compounds is due to hydrogen bonds of the О⋅⋅⋅H and F⋅⋅⋅H types, СН⋅⋅⋅π and F⋅⋅⋅π interactions, and stacking effect.

Polymer composites are one of the types of modern functional materials. This class includes many different in structure and field of application materials, including dispersed-filled polymer composites [1]. Such materials are made by mixing a polymer matrix in a fluid state with a powder filler and then curing. The properties of the resulting materials are influenced by a variety of factors, including the nature of the preliminary (prior to addition to the mixture with the polymer) mechanical-chemical processing of the filler.

The antiradical properties of essential oil and water-alcohol extracts of oregano (Origanum vulgare L.), which grows in the Krasnoyarsk territory, were studied in model reactions with a free stable 2,2-diphenyl-1-picrylhydrazyl radical. Essential oil is obtained by exhaustive hydro-distillation. Separate fractions of oil: first 10 minutes from the start of the distillation, the second – after 20 min, the third after 40 min, and the fourth in 80 minutes, a fifth fraction was collected after the end of hydroponically. The results of the DPPH test showed that all the studied samples of essential oil exhibit anti-radical activity (ARA), the values of which increase from 30.4% (the first fraction) to 51.0% (the fifth). The ARA of O. vulgare whole oil was 36.1%. The ARA values of O. vulgare water-alcohol extracts vary from 56.6 to 100% depending on the alcohol concentration and the volume of the added extract. The highest anti-radical activity is 70% extract, and the lowest – 96%. According to the ARA value, the studied extracts and essential oil are O. vulgare, which grows in the Siberian region, can be arranged in the following order: 70% water-alcohol extract > 40% extract > 20% extract > water extract > 96% alcohol extract > essential oil.

Genes homologous to PSY1 and PSY2 that encode phytoene synthase isoforms in Capsicum species C. baccatum, C. chinense, C. frutescens, C. tovarii, C. eximium, and C. chacoense were identified. High conservatism of functionally significant sites of phytoene synthases of the analyzed accessions was revealed. It was found that only PSY1-based clustering of pepper species corresponds to the traditional Capsicum phylogeny; C. eximium was a part of the Purple corolla complex, and C. chacoense was equidistant from Annuum and Baccatum clades. The absence of significant differences between PSY1 and PSY2 of yellow-fruited C. chinense and red-fruited pepper accessions was shown. The yellow color of C. chinense fruit may be the result of both decreased PSY1 expression and increased PSY2 transcription. Thus, it was demonstrated that the acquired fruit pigmentation retains strict phylogenetic limitations, which, however, can be overcome using artificial selection for the activity of phytoene synthase PSY1.

This paper reports a process for the growth of optically homogeneous lithium niobate single crystals containing boron as a dopant. A LiNbO3:B crystal has been grown by the Czochralski technique using a single-phase growth charge synthesized from a Nb2O5:B precursor and lithium carbonate. We have assessed the optical quality of the crystal by a high-speed method from the number of scattering centers, evaluated its single-domain state by piezoacoustic measurements, and calculated its d333 piezoelectric modulus component. The results demonstrate that the crystal has a high degree of optical uniformity and is single-domain. The proposed method for LiNbO3:B crystal growth can serve as a basis of a commercial-scale process for the preparation of doped lithium niobate single crystals for various engineering applications.

Gold complexes [Ph3PR]+[Au(CN)2I2-trans]−, where R = Et (1), CH2Ph (2), Ph (3), were synthesized by the reaction of potassium dicyanodiiodoaurate with tetraorganylphosphonium chlorides in acetonitrile and were structurally characterized. The phosphorus atoms in the cations are in a tetrahedral environment. In the centrosymmetric square [Au(CN)2I2]− anions of complexes 1–3, the Au—I distances have similar values (2.617(2), 2.623(2), and 2.611(2) A, respectively); the largest bond length is observed in complex 2. The Au-C and C≡N bond lengths in complexes 1–3 are 1.993(5), 2.002(4), 2.003(19) A and 1.130(6), 1.074(7), 1.12(2) A, respectively. In the tetrahedral [Ph3PR]+ cations (C-P-C angles, 105.5(10)–111.2(7)°), the P-C distances vary in the range of 1.797(4)–1.816(4) A. The structural organization of the crystals of compounds 1–3 is due mainly to weak N⋯H-C hydrogen bonds (2.44–2.74 A) between hydrogen atoms of the cations and nitrogen atoms of the anions.

Tetra(p-tolyl)antimony 2,4,6-trichlorophenoxide p-Tol4SbOC6H2Cl3-2,4,6 (1) and tetra(p-tolyl)antimony 3,4,5-trifluorobenzoate p-Tol4SbOС(O)C6H2F3-3,4,5 (2) are synthesized by the interaction of penta(p-tolyl)antimony with equimolar amounts of 2,4,6-trichlorophenol and 3,4,5-trifluorobenzoic acid in a benzene solution. Compounds 1 and 2 are also obtained by ligand redistribution reactions between penta(p-tolyl)antimony and symmetric antimony derivatives p-Tol3SbХ2. The crystal structures and structural features of compounds 1 and 2, in which antimony atoms have a trigonal bipyramidal coordination of substituents with axially located oxygen-containing ligands, are determined by single crystal X-ray diffraction.

In a recent computational study, we revealed some mechanistic aspects of TRPV1 (transient receptor potential channel 1) thermal activation and gating and proposed a set of probable functionally important residues — “hot spots” that have not been characterized experimentally yet. In this work, we analyzed TRPV1 point mutants G643A, I679A + A680G, and K688G/P combining molecular modeling, biochemistry, and electrophysiology. The substitution G643A reduced maximal conductivity that resulted in a normal response to moderate stimuli, but a relatively weak response to more intensive activation. I679A + A680G channel was severely toxic for oocytes most probably due to abnormally increased basal activity of the channel (“always open” gates). The replacement K688G presumably facilitated movements of TRP domain and disturbed its coupling to the pore, thus leading to spontaneous activation and enhanced desensitization of the channel. Finally, mutation K688P was suggested to impair TRP domain directed movement, and the mutated channel showed ~100-fold less sensitivity to the capsaicin, enhanced desensitization and weaker activation by the heat. Our results provide a better understanding of TRPV1 thermal and capsaicin-induced activation and gating. These observations provide a structural basis for understanding some aspects of TRPV1 channel functioning and depict potentially pathogenic mutations.

Tris(4-fluorophenyl)antimony dicarboxylates (4-FC6H4)3Sb[OC(O)R]2, where R = CH2Cl (I), C6F5 (II), C6F4H-2 (III), CF2CF3 (IV), CF2CF2CF3 (V), and (3-FC6H4)3Sb[OC(O)C6F4H-2]2 (VI) have been synthesized by the reaction of tris(fluorophenyl)antimony with chloroacetic, pentafluorobenzoic, tetrafluorobenzoic, pentafluoropropionic, and heptafluorobutyric acids in the presence of tert-butyl hydroperoxide. According to X-ray diffraction data, the Sb atoms in complexes I–VI have trigonal bipyramidal coordination. The axial OSbO angles are 177.68(9)°, 177.44(12)°, 176.59(7)°, 179.59(6)°, 179.63(9)°, and 175.72(12)°. The Sb–O and Sb–С bond lengths are 2.125(2), 2.136(2) and 2.101(3)–2.112(3) A in I, 2.118(3), 2.119(3) and 2.094(5)–2.109(5) A in II, 2.120(2), 2.137(2) and 2.114(2)–2.122(3) A in III, 2.133(2), 2.153(2) and 2.086(2)–2.098(2) A in IV, 2.146(3), 2.164(3) and 2.090(4)–2.093(4) A in V, 2.123(3), 2.140(3) and 2.109(5)–2.122(5) A in VI.

Essential oil from the roots of calamus marsh (Acorus calamus L) was isolated by the method of exhaustive hydroparodistillation, growing on the Krasnoyarsk territory. Separate fractions of essential oil were obtained depending on the duration of isolation. The component composition of the essential oil, the main components of which are acorenone, butyrate α-terpineol, germacrene B, camphor. The antiradical properties of the essential oil of A. сalamus roots growing in the Siberian region, as well as the antiradical properties of its individual fractions were studied for the first time in order to determine the most promising samples as sources of biologically active complexes. To determine the antiradical activity, the reaction of the essential oil components with a stable free 2,2-diphenyl-1-picrylhydrazyl radical was used. The antiradical activity of all studied samples of essential oils was established. There was an increase in antiradical activity with a decrease in the content of monoterpenes in the composition of the essential oil. The lowest antiradical activity (17.5%) was shown by the fraction of essential oil with a high content of monoterpenes, the highest (~100%) – fractions with a high content of oxygen-containing compounds. It was revealed that the ability of components of individual fractions of A. сalamus essential oil to inhibit DPPH radicals is comparable with the antiradical activity of ascorbic acid solutions of equivalent concentration.

By the method of exhaustive hydroponically obtained essential oil from beans of Heracleum dissectum Ledeb., growing in the Krasnoyarsk region. Separate fractions of oil were obtained: the first after 45 minutes from the beginning of distillation, the second – after 2 hours, the third-after 5 hours, the fourth fraction was collected after the end of hydro-distillation. The component composition of both whole essential oil and its separate fractions was studied. The main components are octyl acetate (60.0%), octyl-2-methylpropanoate (10.2%), n-hexyl-2-methylbutanoate (9.0%). The main amount of octyl acetate (64.7%) is concentrated in the first fraction of the oil. The antimicrobial activity of various fractions of essential oil of borscht dissected against strains of opportunistic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus 209p, MRSA, Proteus vulgaris. It was found that, depending on the duration of isolation, the antimicrobial activity of essential oil fractions in relation to Staphylococcus aureus 209p, MRSA and Pseudomonas aeruginosa decreases, and in relation to Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris increases. The most pronounced inhibitory effect of the third and fourth fractions of essential oil against Klebsiella pneumonia. The antiradical activity of all studied samples of borscht essential oil dissected in reaction with stable free 2,2-diphenyl-1-picrylhydrazyl radical was established. The first fraction showed minimal antiradical activity (15.1%), the fourth – maximum (49.2%).

Objectives. This study is devoted to developing new-generation nickel (Ni) catalysts for the purification of a nitrogen–hydrogen mixture from carbon oxides, which should encompass the best qualities of the NIAP-07-series solid catalysts. Methods. This study used derivatographic and radiographic methods; temperature-programmed recovery, decomposition, and joint temperature-programmed decomposition and recovery; and low-temperature nitrogen adsorption (specific surface determination). The mechanical strength of catalysts was determined using an MP-2C device by crushing granules with an applied load on the end face. The chemical composition and catalytic activity were determined by the methods of TU 2178-003-00209510 Technical Conditions. Results. Many studies regarding Ni–aluminum (Al)–calcium (Ca) methanation catalyst at all stages of its preparation have been conducted. It is demonstrated that Ni hydrocarboxyaluminate, a precursor of the active component of the catalyst, is formed when Ni hydroxocarbonate is mixed with active alumina in the presence of an aqueous solution of ammonia, and its chemical formula is established. Moreover, it was found that the mechanical strength of the catalyst is determined by the amount of industrial Ca aluminate added to the Ni–Al composition. The compositions of catalysts with different contents of the active component have been optimized. Conclusions. The developed catalyst has a low activation temperature and high catalytic activity, thermal stability, and mechanical strength and is resistant to organic and alkaline carbon dioxide absorbers. The catalyst can be produced in the form of a ring, cylindrical tablets, and extrudates of various geometric sizes. The methanation unit at Stavrolen (Budennovsk, Stavropol krai, Russia) has begun commercially operating the catalyst.

LiTaO3 ceramics has been produced from a fine powder synthesized by a sol-gel method from a Li,Ta-containing citrate precursor, and its microstructure and mechanical and electrical properties have been studied. Young’s modulus and microhardness of the ceramic lithium tantalite have been determined. The critical stress intensity factor of mode I KIC, which is a criterion for the crack resistance of a material, has been evaluated, and the effective fracture energy of the LiTaO3 ceramics has been determined. The complex impedance dispersion Z*(ω) has been studied, and temperature dependences of dielectric constant and conductivity have been measured in the temperature range ~300–705 K, which is crucial for the acoustoelectronic applications of ceramic lithium tantalate. In the temperature range studied, the static conductivity and relaxation time of LiTaO3 ceramics have been determined. The charge transport activation enthalpies for various temperature ranges have been estimated.

Nowadays, considerable efforts are focused on advancing DNA detection methods, which are extremely important in clinical diagnostics, pathogen determination, gene therapy, and forensic analysis. A one-pot sensitive microplate-based chemiluminescent assay coupled with catalytic hairpin assembly (CHA) amplification for detection of a 35-mer DNA oligonucleotide was developed. To improve the assay sensitivity, a triple amplification strategy based on the application of CHA (1), streptavidin-polyperoxidase conjugate (Stp-polyHRP) (2), and an enhanced chemiluminescent reaction (3) was used. The one-pot format of the assay, where all steps of the DNA determination are performed in the same well without transfer of samples from one test tube to another, increased its precision. The proposed assay detected the target DNA in the fM range and distinguished the target DNA from related DNAs, demonstrating its high sensitivity and high selectivity. Moreover, the assay was applied successfully for the quantitative determination of the target in spiked samples of human plasma. A microplate format of the assay was convenient for the analysis of a large number of samples. This study provides a prospective tool for DNA detection. Graphical abstract.

Despite the growing demand for hydrogen peroxide it is almost exclusively manufactured by the energy-intensive anthraquinone process. Alternatively, H2O2 can be produced electrochemically via the two-electron oxygen reduction reaction, although the performance of the state-of-the-art electrocatalysts is insufficient to meet the demands for industrialization. Interestingly, guided by first-principles calculations, we found that the catalytic properties of the Co–N4 moiety can be tailored by fine-tuning its surrounding atomic configuration to resemble the structure-dependent catalytic properties of metalloenzymes. Using this principle, we designed and synthesized a single-atom electrocatalyst that comprises an optimized Co–N4 moiety incorporated in nitrogen-doped graphene for H2O2 production and exhibits a kinetic current density of 2.8 mA cm−2 (at 0.65 V versus the reversible hydrogen electrode) and a mass activity of 155 A g−1 (at 0.65 V versus the reversible hydrogen electrode) with negligible activity loss over 110 hours. Producing H2O2 electrochemically currently use electrocatalysts that are insufficient to meet the demands for industrialization. A single-atom electrocatalyst with an optimized Co–N4 moiety incorporated in nitrogen-doped graphene is shown to exhibit enhanced performance for H2O2 production.

New ionic antimony complexes with a three-coordinated carbon atom in their cations, namely, [(Ph4SbO)3C]+[OSO2C6H3(NO2)2-2,4]– ⋅ 3PhH (32%) and [(p-Tol4SbO)3C]+Br– (traces), have been isolated when the products of reactions between pentaphenylantimony and 2,4-dinitrobenzenesulfonic acid and between penta(p-tolyl)antimony and hydrobromic acid were crystallized from a benzene–octane mixture in air along with the target products, such as tetraphenylantimony 2,4-dinitrobenzenesulfonate and tetra(p-tolyl)antimony bromide. The cations have nearly planar СO3Sb3 cores. The ОСО and COSb angles are close to 120°, whereas the C–O bonds vary within 1.277(4)–1.290(3) A, and the Sb–O distances (2.266(2)–2.299(2) A) exceed the sum of the covalent radii of antimony and oxygen atoms. It has been experimentally established that these complexes are formed as a result of interactions between the target products of the above-mentioned reactions with bis(tetraarylantimony) carbonates, which are also formed under the conditions of these reactions from pentaarylantimony and atmospheric carbon dioxide.

Importance: Sodium glucose cotransporter 2 inhibitors reduce morbidity and mortality in patients with heart failure and reduced ejection fraction (HFrEF). Clinicians may find estimates of the projected long-term benefits of sodium glucose cotransporter 2 inhibitors a helpful addition to clinical trial results when communicating the benefits of this class of drug to patients. Objective: To estimate the projected long-term treatment effects of dapagliflozin in patients with HFrEF over the duration of a patient’s lifetime. Design, Setting, and Participants: Exploratory analysis was performed of Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF), a phase 3 randomized, placebo-controlled clinical trial conducted at 410 sites in 20 countries. Patients with an ejection fraction less than or equal to 40% in New York Heart Association functional classification II to IV and elevated plasma levels of N-terminal pro B-type natriuretic peptide were enrolled between February 15, 2017, and August 17, 2018, with final follow-up on June 6, 2019. Mean (SD) duration of follow-up was 17.6 (5.2) months. Interventions: Dapagliflozin, 10 mg, once daily vs placebo in addition to standard therapy. Main Outcomes and Measures: The primary composite outcome was time to first hospitalization for heart failure, urgent heart failure visit requiring intravenous therapy, or cardiovascular death. The trial results were extrapolated to estimate the projected long-term treatment effects of dapagliflozin over the duration of a patient’s lifetime for the primary outcome and the secondary outcome of death from any cause. Results: A total of 4744 patients (1109 women [23.4%]; 3635 men [76.6%]) were randomized in DAPA-HF, with a mean (SD) age of 66.3 (10.9) years. The extrapolated mean event-free survival for an individual aged 65 years from a primary composite end point event was 6.2 years for placebo and 8.3 years for dapagliflozin, representing an event-free survival time gain of 2.1 years (95% CI, 0.8-3.3 years; P = .002). When considering death from any cause, mean extrapolated life expectancy for an individual aged 65 years was 9.1 years for placebo and 10.8 years for dapagliflozin, with a gain in survival of 1.7 years (95% CI, 0.1-3.3; P = .03) with dapagliflozin. Similar results were seen when extrapolated across the age range studied. In analyses of subgroups of patients in DAPA-HF, consistent benefits were seen with dapagliflozin on both event-free and overall survival. Conclusions and Relevance: These findings indicate that dapagliflozin provides clinically meaningful gains in extrapolated event-free and overall survival. These findings may be helpful in communicating the benefits of this treatment to patients with HFrEF. Trial registration: ClinicalTrials.gov Identifier: NCT03036124.

DNA-architectural proteins play a major role in organization of chromosomal DNA in living cells by packaging it into chromatin, whose spatial conformation is determined by an intricate interplay between the DNA-binding properties of architectural proteins and physical constraints applied to the DNA by a tight nuclear space. Yet, the exact effects of the cell nucleus size on DNA-protein interactions and chromatin structure currently remain obscure. Furthermore, there is even no clear understanding of molecular mechanisms responsible for the nucleus size regulation in living cells. To find answers to these questions, we developed a general theoretical framework based on a combination of polymer field theory and transfer-matrix calculations, which showed that the nucleus size is mainly determined by the difference between the surface tensions of the nuclear envelope and the endoplasmic reticulum membrane as well as the osmotic pressure exerted by cytosolic macromolecules on the nucleus. In addition, the model demonstrated that the cell nucleus functions as a piezoelectric element, changing its electrostatic potential in a size-dependent manner. This effect has been found to have a profound impact on stability of nucleosomes, revealing a previously unknown link between the nucleus size and chromatin structure. Overall, our study provides new insights into the molecular mechanisms responsible for regulation of the cell nucleus size, as well as the potential role of nuclear organization in shaping the cell response to environmental cues.SIGNIFICANCE STATEMENTThe cell nucleus plays a central role in the life of eukaryotic cells, providing the highest level of control of intracellular processes. Depending on the stage of the cell cycle and / or surrounding environment, the size of the cell nucleus may undergo changes that are believed to cause chromatin reorganization, affecting gene transcription. At present, however, there is no clear understanding of the molecular mechanisms that may be responsible for such regulation, whose exact effect on chromatin structure remains unclear. In this study, by developing an advanced computational approach, we explore these issues from a physical perspective, revealing previously unknown mechanisms contributing to organization of the cell nucleus and chromatin.

The microstructure of ceramic lithium tantalite LiTaO3, obtained on the basis of finely dispersed microcrystalline monophasic powder, was studied by the probe microscopy. A comparative study of the dispersion of the complex impedance Z*(ω) of LiTaO3 and a crystalline sample of a non-polar X-orientation slice, grown by the Czochralski method, was carried out. Using measured Z and φ values, the real and imaginary components of the complex dielectric constant and impedance (admittance) are determined.

Solutions of poly(acrylic acid) mixtures with poly(sodium styrenesulfonate) in water and in decimolar hydrochloric acid are studied by potentiometry, viscometry, and rotational rheometry. It is shown that, in a wide range of mixture compositions, thermosensitive polyelectrolyte complexes are formed via ion–dipole interactions of functional groups of polymers. The formation of complexes in the semidilute solution regime is accompanied by a significant increase in viscosity as compared with solutions of the initial polymers, which makes it possible to obtain systems with high viscosity without using large concentrations of polyelectrolytes. The dependence of viscosity on the composition of the mixture passes through a maximum corresponding to the most complete binding of the components of the complex, and the position of the maximum does not depend on the molecular weight of poly(sodium styrenesulfonate) and is determined by the ratio of the concentrations of the functional groups of the polymers. The frequency dependences of the storage modulus and the loss modulus demonstrate that the system experiences strong structuring in the process of complex formation.

β thalassaemia intermedia (βTI) are a heterogeneous group of disorders known to be extremely phenotypically diverse. This group is more complex to manage as no definitive treatment guidelines exist unlike for β thalassaemia major (βTM). There are only a few studies looking at genotype phenotype associations of βTI outside the Mediterranean region. The reasons for the diverse clinical phenotype in βTI are unknown. We categorized fifty Sri Lankan patients diagnosed with βTI as mild, moderate or severe according to published criteria. DNA samples were genotyped for β thalassaemia mutations, α globin genotype and copy number and known genetic modifiers of haemoglobin F production. There were 26/50 (52.0%) in mild group and 12/50 (24.0%) each in moderate and sever categories. 18/26 (69.2%) classified as mild were β heterozygotes and 17/18 (94.4%) had excess α globin genes. 11/12 (91.6%) classified as moderate were β heterozygotes and 8/11 (72.2%) had excess α globin genes. In contrast, 8/12 (66.7%) classified as severe were β homozygotes and 7/8(87.5%) had α globin gene deletions. In Sri Lanka, co-inheritance of either excess α globin genes in β thalassaemia heterozygotes or α globin gene deletions in β thalassaemia homozygotes is a significant factor in modulating disease severity.

A comparative study of lipid and fatty acid status at the early stages of pink salmon’s ontogenesis has been carried out in prespawn eggs, at the stage of eye pigmentation, and in the hatched prelarvae under ecological conditions of a natural environment (Indera River, Kola Peninsula). It is shown that the high plasticity of pink salmon is due to the activation and combination of complex biochemical mechanisms at the early stages of development, providing both the sensitivity and the sustainability of the species, which contributes to the formation of the species’ high potential at high latitudes. Metabolically mature pink salmon eggs are characterized by a high level of total lipids with a high amount of the structural and energetic components that provide optimal development of the embryos. Metabolic processes are activated at the stage of eye pigmentation in autumn, which affects the changes in the spectrum of individual classes of lipids and fatty acids and their ratio indicators. The prelarvae that hatched in winter at temperatures below zero have a low content of phospholipids, triacylglycerols, and 16:1ω-7, 18:3ω-3, and 20:5ω-3 fatty acids as well as high level of cholesterol, cholesterol esters, and a ratio index of 20:4ω-6/18:2ω-6 fatty acids, while the high content of dominant 18:1ω-9 and 22:6ω-3 fatty acids remains the same. Multidirectional changes of lipid and fatty acid levels at the stage of eye pigmentation (the most sensitive stage of embryogenesis) and in pink salmon prelarvae after hatching are caused by specific processes of metabolism intensification of the developing organism.

A kinetic model was developed for the reaction of ethylene oxidation to acetaldehyde by p-benzoquinone (Q) at 30 ℃ catalyzed by the cationic palladium(II) complexes in a binary acetonitrile—water solvent at a molar fraction of water of 0.67. The three-route mechanism was proposed that adequately describes all experimental dependences of the concentrations of consumed ethylene on time at various partial ethylene pressures and concentrations of palladium, perchloric acid, and Q. The time-dependent (a) palladium distribution between the intermediates and (b) ratio of the rates of steps of acetaldehyde oxidation via different routes were analyzed. The role of the PdII, PdI, and Pd0 complexes in the catalytic formation of olefins was discussed. The quantum chemical estimates of the composition of the coordination sphere for several intermediates and probabilities of some elementary steps in the reaction mechanism were obtained.

The reactions of tris(p-tolyl)antimony, tris(3-fluorophenyl)antimony, and tris(4-fluorophenyl)antimony with 2-hydroxybenzaldoxime at equimolar amounts in diethyl ether in the presence of hydrogen peroxide have been studied. It has been established that 2-hydroxybenzaldoxime reacts as a bifunctional compound, and the simultaneous oxidation and dearylation of triarylantimony is observed. The products of these reactions are bis(μ3-2-oxybenzaldoximato-O, O′, N)-(μ2-oxo)-tetrakis(p-tolyl)-diantimony (I), -tetrakis(3-fluorophenyl)diantimony (II), and -tetrakis(4-fluorophenyl)diantimony (III), in which two structurally equivalent antimony atoms linked via two tridentate bridging ligands and an oxygen atom have a distorted octahedral coordination with the C2O3N surrounding according to X-ray diffraction study data. Their molecules have three types of Sb–O distances with the bridging oxygen atom (1.942(5), 1.946(5) A in IA and IB, respectively, 1.948(3), 1.953(2) A in II, and 1.954(3), 1.958(3) A in III), the oxygen atoms of oxime groups (2.087(7) A in IA and IB, 2.076(2), 2.097(2) A in II, and 2.094(3), 2.081(3) A in III), and the oxygen atoms of hydroxy groups (2.022(7), 2.024(7) A in IA and IB, respectively, 2.002(3), 2.010(3) A in II, and 2.015(4), 2.019(3) A in III) and Sb⋯N coordination bonds (2.236(8), 2.238(9) A in IA and IB, respectively, 2.256(3), 2.230(3) A in II, and 2.266(4), 2.251(4) A in III).

Ordered defective structures in lithium niobate crystals have been established. The phenomenon is a result of non-equilibrium processes of a different nature: photo-induced light scattering, laser ablation, and creation of cracks during relieving mechanical stresses. The shape of such structures depends on the nature and energy that affect a crystal. A number of concentric areas with a different density of laser-induced defects with a changed refractive index appear during photoinduced light scattering. Concentric clusters of microdomains appear in a macrodomain of another sign at laser ablation as a result of local switching under impulse laser radiation. A number of microcracks with a fractal structure appear near main macro-crack during cracking under mechanical stress. Thus, appearance of ordered defective structure occurs not only in the local spot of direct exposure to laser radiation, mechanical stress, etc., but also in some volume of a crystal around it.

Triarylbismuth dicarboxylates Ar3Bi[OC(O)R]2, Ar = p-Tol, R = CH2Cl (I); Ar = Ph, R = C6H4OMe-2 (II), CH=CHPh (III) have been synthesized by the reactions of tri(para-tolyl)bismuth with monochloroacetic acid and triphenylbismuth with 2-methoxybenzoic and cinnamic acids in methyl-tert-butyl ether in the presence of tert-butyl hydroperoxide with a high yield. The Bi atoms in complexes I–III have a distorted trigonal bipyramidal coordination with carboxylate ligands in axial positions (OBiO angles, 171.06(6)° (I), 170.46(12)° (II), 175.39(8)° (III)). The Sb-O and Sb-C bond lengths are 2.283(2), 2.288(2) A and 2.185(2)–2.199(2) A (I), 2.265(7), 2.268(7) A and 2.194(7)–2.218(8) A (II), and 2.310(2), 2.310(2) A and 2.200(2)–2.210(3) A (III). Molecules of complexes I–III have intramolecular contacts between the Bi atom and the O atoms of carbonyl groups: the Bi⋯O(=C) distances are 2.990(2), 2.985(3) A (I), 2.753(8), 2.739(8) A (II), and 2.688(2) A (III). The structural organization in crystals of complexes I–III is caused by weak inter-molecular hydrogen bonds H⋯O of 2.61–2.65 A (I), 2.47–2.50 A (II), and 2.56 A (III).

The Shc family adaptor p66Shc acts as a negative regulator of proliferative and survival signals triggered by the B-cell receptor and, by enhancing the production of reactive oxygen species, promotes oxidative stress-dependent apoptosis. Additionally, p66Shc controls the expression and function of chemokine receptors that regulate lymphocyte traffic. Chronic lymphocytic leukemia cells have a p66Shc expression defect which contributes to their extended survival and correlates with poor prognosis. We analyzed the impact of p66Shc ablation on disease severity and progression in the Eμ-TCL1 mouse model of chronic lymphocytic leukemia. We showed that Eμ-TCL1/p66Shc-/- mice developed an aggressive disease that had an earlier onset, occurred at a higher incidence and led to earlier death compared to that in Eμ-TCL1 mice. Eμ-TCL1/p66Shc-/- mice displayed substantial leukemic cell accumulation in both nodal and extranodal sites. The target organ selectivity correlated with upregulation of chemokine receptors whose ligands are expressed therein. This also applied to chronic lymphocytic leukemia cells, where chemokine receptor expression and extent of organ infiltration were found to correlate inversely with these cells' level of p66Shc expression. p66Shc expression declined with disease progression in Eμ-TCL1 mice and could be restored by treatment with the Bruton tyrosine kinase inhibitor ibrutinib. Our results highlight p66Shc deficiency as an important factor in the progression and severity of chronic lymphocytic leukemia and underscore p66Shc expression as a relevant therapeutic target.

Optimal conditions are selected for ethylene and cyclohexene oxidation reactions in the acetonitrile (AN)–water system in the presence of $${\text{Pd}}{{({\text{AN}})}_{x}}({{{\text{H}}}_{2}}{\text{O}})_{{4 - x}}^{{2 + }}$$ complexes. It is shown that hydrogen peroxide oxidizes hydroquinone (QН2) in acetonitrile solutions and in ionic liquids ( $${\text{BMI}}{{{\text{M}}}^{ + }}{\text{BF}}_{4}^{ - },$$ $${\text{BMI}}{{{\text{M}}}^{ + }}{\text{PF}}_{6}^{ - }$$ ), and the rates of ethylene oxidation in the $${\text{BMI}}{{{\text{M}}}^{ + }}{\text{PF}}_{6}^{ - }$$ ionic liquid in the presence of p-benzoquinone (Q) and hydroquinone are the same. It is shown that solid and soluble phthalocyanine iron complexes catalyze oxidation of olefins by oxygen in acidic acetonitrile media by converting p-benzoquinone to the third catalyst of the process. The apparent first-order rate constants of hydroquinone oxidation by oxygen are determined. The use of the IL–Н2О–Н2SO4 system is found to be inappropriate for cyclohexanone synthesis because of the formation of byproducts of cyclohexene conversion.

This article is dedicated to the isolation of lignin-containing fractions from the flaxseeds Linum usitatissimum L. The main component of these fractions is lignan-secoisolariciresinol diglucoside (SDG). The authors have developed an effective extraction method for obtaining lignan-containing fractions from flaxseed with a satisfactory yield of SDG-containing fraction and its isomers. This method was implemented by microwave irradiation pretreatment of the seeds and by using environmentally friendly extraction solvents. A 50/50 mixture of water and ethanol was chosen as extraction agents. Microwave irradiation pretreatment of ground flaxseeds was carried out at 450W and 800W for 5 seconds, 4 times with an interval of 5 seconds. SDG-identification was performed on an Agilent 1200 series high performance liquid chromatograph and a Shimadzu UV-1900 automatic dual-beam UV spectrophotometer. The results of the conducted studies showed that the microwave irradiation pretreatment of flaxseeds at 800W increases the yield of SDG relative to the dry residue by 34.76% in comparison with the classical alkaline method, and the content of the amount of lignans in recalculation on chicory acid was 43.53%. Thus, the extraction method of lignans-containing extract including the stage of pretreatment by microwave irradiation with power of 800W is the most effective method.

Accurate positioning of proteins on chromosomal DNA is crucial for its proper organization as well as gene transcription regulation. Recent experiments revealed existence of periodic patterns of nucleoprotein complexes on DNA, which frequently cannot be explained by sequence-dependent binding of proteins. Previous theoretical studies suggest that such patterns typically emerge as a result of the proteins’ volume-exclusion effect. However, the role of other physical factors in patterns’ formation, such as the length of DNA, its sequence heterogeneity, and protein binding cooperativity/binding competition to DNA, remains unclear. To address these less understood yet important aspects, we investigated potential effects of these factors on protein positioning on finite-size DNA by using transfer-matrix calculations. It has been found that upon binding to DNA, proteins form oscillatory patterns that span over the length of up to ∼10 times the size of the protein binding site, with the shape of the patterns being strongly dependent on the length of DNA and the proteins’ binding cooperativity to DNA. Furthermore, calculations showed that small variations in the proteins’ affinity to DNA due to its sequence heterogeneity do not much change the main geometric characteristics of the observed protein patterns. Finally, competition between two different types of proteins for binding to DNA has been found to lead to formation of highly diverse and complex alternating positioning of the two proteins. Altogether, these results provide new insights into the roles of physicochemical properties of proteins, the DNA length, and DNA-binding competition between proteins in formation of protein positioning patterns on DNA.

Context: Ibrutinib inhibits BTK with the most typical response in CLL being partial remission (PR) with measurable minimal residual disease (MRD) in blood. Remission is usually maintained until development of genetically-driven resistance. Objective: Mechanism of adaptation and survival in MRD. Patients and Methods: Pre-treatment CLL cells and under-treatment MRD were systematically collected from 33 high-risk CLL patients. Samples were characterized by high-dimensional, single-cell flow cytometry; bulk genomic, transcriptomic, and chromatin accessibility profiling; and single-cell RNA-seq profiling. Results: The genetic composition of MRD remained constant across timepoints, indicating that ibrutinib did not have any impact in shaping its genomic diversity. Ibrutinib induced chromatin dynamics in MRD resulting in a predominantly closed state. Chromatin regions that became more accessible under ibrutinib were enriched of binding sites for transcription factor that lay downstream ERK signaling. Regions that turned into a less accessible state were enriched for the binding sites of TF emanating from the BCR. At the transcriptomic level, most of the differentially expressed genes between pre- and post-treatment samples were downregulated in MRD, while only a fraction was upregulated. IL4, NF-kB, and metabolism and proliferation signatures were downregulated in MRD, while MAPK and RAS signatures were upregulated. CLL spleen samples from TCL1 mice under ibrutinib treatment showed an upregulation of MAPK pathway genes compared to untreated mice. Single-cell transcriptomes revealed a distinct post-treatment cell population driven by MAPK activity that functionally pre-existed in a fraction of CLL cells of baseline samples before ibrutinib start. At the signaling level, ibrutinib had no effect on the integrity of RAS-BRAF-MAPK-ERK pathway protein expression upon crosslinking of the BCR with anti-IgM but not after stimulation of TLR9 or CD40. Functional validation on primary samples by western blotting shows that RAS/ERK can be activated by BCR stimulation, irrespective of ibrutinib treatment in ex vivo experiments. Pharmacological inhibition of MEK (trametinib) and ERK (ulixertinib) synergized with ibrutinib, leading to decreased cell viability. Conclusions: MRD under ibrutinib adapts its phenotype in an epigenetic way to maintain functional competence of BCR signaling via the MAPK pathway, which turned to be a vulnerability of MRD persisting under ibrutinib.

The mimicking of the architectonics of native tissue, biodegradable non-woven fibrous mats is one of the most promising forms of scaffolding for tissue engineering. The key properties needed for their successful application in vivo, such as biodegradability, biocompatibility, morphology, mechanical properties, etc., rely on their composition and appropriate 3D structure. A multicomponent system based on biodegradable synthetic (polycaprolactone, oligo-/polylactide) and natural (chitosan, gelatin) polymers, providing the desired processing characteristics and functionality to non-woven mats fabricated via the electrospinning technique, was developed. The solid-state reactive blending of these components provided a one-step synthesis of amphiphilic graft copolymer with an ability to form stable ultra-fine dispersions in chlorinated solvents, which could be successfully used as casting solvents for the electrospinning technique. The synthesized graft copolymer was analyzed with the aim of fractional analysis, dynamic laser scattering, FTIR-spectroscopy and DSC. Casting solution characteristics, namely viscosity, surface tension, and electroconductivity, as well as electrospinning parameters, were studied and optimized. The morphology, chemical structure of the surface layer, mechanical properties and cytocompatibility were analyzed to confirm the appropriate functionality of the formed fibrous materials as scaffolds for tissue engineering.

ChemistryOpen 9(6), 641 - 648 (2020). doi:10.1002/open.201900276, The synthetic function‐spacer‐lipid (FSL) amphiphile biotin‐CMG‐DOPE is widely used for delicate ligation of living cells with biotin residues under physiological conditions. Since this molecule has an “apolar‐polar‐hydrophobic” gemini structure, the supramolecular organization is expected to differ significantly from the classical micelle. Its organization is investigated with experimental methods and molecular dynamics simulations (MDS). Although the linear length of a single biotin‐CMG‐DOPE molecule is 9.5 nm, the size of the dominant supramer globule is only 14.6 nm. Investigations found that while the DOPE tails form a hydrophobic core, the polar CMG spacer folds back upon itself and predominantly places the biotin reside inside the globule or planar layer. MDS demonstrates that, Published by Wiley-VCH-Verl., Weinheim

Antibiotics (AB) resistance is a major threat to global health, thus the development of novel AB classes is urgently needed. Lantibiotics (i.e. nisin) are natural compounds that effectively control bacterial populations, yet their clinical potential is very limited. Nisin targets membrane-embedded cell wall precursor — lipid II — via capturing its pyrophosphate group (PPi), which is unlikely to evolve, and thus represents a promising pharmaceutical target. Understanding of exact molecular mechanism of initial stages of membrane-bound lipid II recognition by water-soluble nisin is indispensable. Here, using molecular simulations, we demonstrate that the structure of lipid II is determined to a large extent by the surrounding water-lipid milieu. In contrast to the bulk solvent, in the bilayer only two conformational states remain capable of nisin binding. In these states PPi manifests a unique arrangement of hydrogen bond acceptors on the bilayer surface. Such a “pyrophosphate pharmacophore” cannot be formed by phospholipids, which explains high selectivity of nisin/lipid II recognition. Similarly, the “recognition module” of nisin, being rather flexible in water, adopts the only stable conformation in the presence of PPi analogue (which mimics the lipid II molecule). We establish the “energy of the pyrophosphate pharmacophore” approach, which effectively distinguishes nisin conformations that can form a complex with PPi. Finally, we propose a molecular model of nisin recognition module/lipid II complex in the bacterial membrane. These results will be employed for further study of lipid II targeting by antimicrobial (poly)cyclic peptides and for design of novel AB prototypes.

Previously, we have described the preparation of a novel fibroin methacrylamide (FbMA), a polymer network with improved functionality, capable of photocrosslinking into Fb hydrogels with elevated stiffness. However, it was unclear how this new functionality affects the structure of the material and its beta-sheet-associated crystallinity. Here, we show that the proposed method of Fb methacrylation does not disturb the protein&rsquo, s ability to self-aggregate into the stable beta-sheet-based crystalline domains. Fourier transform infrared spectroscopy (FTIR) shows that, although the precursor ethanol-untreated Fb films exhibited a slightly higher degree of beta-sheet content than the FbMA films (46.9% for Fb-F-aq and 41.5% for FbMA-F-aq), both materials could equally achieve the highest possible beta-sheet content after ethanol treatment (49.8% for Fb-F-et and 49.0% for FbMA-F-et). The elasticity modulus for the FbMA-F-et films was twofold higher than that of the Fb-F-et as measured by the uniaxial tension (130 &plusmn, 1 MPa vs. 64 &plusmn, 6 MPa), and 1.4 times higher (51 &plusmn, 11 MPa vs. 36 &plusmn, 4 MPa) as measured by atomic force microscopy. The culturing of human MG63 osteoblast-like cells on Fb-F-et, FbMA-F-et-w/oUV, and FbMA-F-et substrates revealed that the photocrosslinking-induced increment of stiffness increases the area covered by the cells, rearrangement of actin cytoskeleton, and vinculin distribution in focal contacts, altogether enhancing the osteoinductive activity of the substrate.

Residual solvent in polymer coatings caused by solvent vapor annealing (SVA) may be used as an indicator of the SVA effectivity for block-copolymer self-assembly and other applications. To analyze the residual changes, temperature-programmed desorption (TPD) technique has been applied to 6–200 nm thick glassy polymer coatings processed by SVA. This method is based on the film thickness contraction and expansion measurements by ellipsometry in vacuum as the temperature of the sample ramps up. The measurements are corrected for the polymer thermal expansion. The polymers used are polystyrene, poly (methyl methacrylate), and poly (2-vinyl pyridine). The TPD curves exhibit up to 2 distinct desorption peaks. One peak appears in the vicinity of the film's glass transition temperature Tg. This feature shows up only if the coating has reached a solvent-induced glass transition during the preceding vapor annealing. The other desorption event is a broad feature appearing at the temperatures below Tg. This peak is observed even for the coatings without previous solvent vapor exposure, although the SVA enhances the effect. The magnitude of the desorption effect corresponds to 1% of the residual solvent content or less for about 30 nm thick films. The desorption demonstrates a clear thickness effect and becomes more pronounced for thinner films, but not exceeding a few % of the residual solvent in 5–8 nm thick coatings. It is supposed that the desorption event in the Tg vicinity is mainly caused by the loss of the solvent or voids from the polymer due to the increased molecular mobility, while the low temperature feature is mostly a desorption of residual gases from the sample surface. Application of the TPD data and sorption-desorption isotherms to the optimization of the SVA procedure and creating a process window plot is demonstrated.

Two new natural compounds, astolides A,B, were isolated from Streptomyces hygroscopicus collected from the alkaline soil obtained from Saratov region, Russia. The structures were elucidated by interpretation of UV spectroscopic, MS, 1D and 2D NMR data. The relative configurations were determined by analysis of NOESY/ROESY spectra and coupling constants. The isolated compounds were evaluated for their inhibitory activity against bacteria, fungi and yeasts and showed pronounced antifungal activity. Both compounds are noticeably cytotoxic, being active against doxorubicin-resistant human leukemia cell line.

Overlap and entanglement formation in aqueous solutions of mixtures of poly(acrylic acid) (PAA) and sodium poly(styrene sulfonate) (PSS) have been studied by means of light scattering and viscometry in comparison with concentration transitions in solutions of the individual polyelectrolytes. In the presence of 0.1 M HCl, PAA forms a complex with PSS due to ion-dipole interactions of carboxylic groups with polyanion sulfonic groups. In the overlap region, a single diffusion mode is split into “fast” and “slow” modes, with the average scattering intensity passing through a maximum. In the region of entanglement network formation, the third mode appears, which we interpret as an interaction mode. The concentration dependences of diffusion coefficients and viscosity of the considered systems coincide with the theoretical predictions of the scaling model of polyelectrolyte solutions. In semidilute regime, the viscosity of the complex significantly exceeds that of initial components, indicating strong structuring of the solution.