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This study aims to determine the effect of nanoparticles (NPs), namely graphene oxide (GO), multilayer carbon tubes (MWCNTs + Fe), magnetite (Fe3O4) and in situ forming brushite (DCPD) in chitosan (CS) based matrices on the cytotoxicity, Pregabalin (PG) release, and in vivo behavior of mechanically stabilized conductive nerve conduits (NCs). NPs change the composites’ hydrophilicity in the order: DCPD (46.8) < MWCNT (54.21) ∼ Fe3O4 (54.44) < GO (65.99) and the water contact angle (47–66°) corresponds to the conditions of cell adhesion. NPs of ≤ 150 μg/ml reduce cell adhesion but don't trigger oxidative stress and toxic effects. Magnetite NPs of 300 µg/ml promote apoptosis in nerve cells. The introduction of PG at stage b during the DCPD formation provides the drug release kinetics closest to the zero-order kinetic model. The most electrically conductive GO- and MWCNTs + Fe - containing NCs have a prolonged biodegradation period of about 6 months, which makes them promising for the regeneration of damaged peripheral nerves in humans.

Abstract A hallmark of microbial biofilms is the self-production of an extracellular molecular matrix that encases the resident cells. The matrix provides protection from the environment, while spatial heterogeneity of gene expression influences the structural morphology and colony spreading dynamics. Bacillus subtilis is a model bacterial system used to uncover the regulatory pathways and key building blocks required for biofilm growth and development. In this work, we report on the emergence of a highly active population of bacteria during the early stages of biofilm formation, facilitated by the extraction of fluid from the underlying agar substrate. We trace the origin of this fluid extraction to the production of poly-γ-glutamic acid (PGA). The flagella-dependent activity develops behind a moving front of fluid that propagates from the boundary of the biofilm towards the interior. The extent of fluid proliferation is controlled by the presence of extracellular polysaccharides (EPS). We also find that PGA production is positively correlated with higher temperatures, resulting in high-temperature mature biofilm morphologies that are distinct from the rugose colony biofilm architecture typically associated with B. subtilis. Although previous reports have suggested that PGA production does not play a major role in biofilm morphology in the undomesticated isolate NCIB 3610, our results suggest that this strain produces distinct biofilm matrices in response to environmental conditions.

ZnO, ZnO/Alginate coatings were obtained on the pre-anodized Ti6Al4V substrates by the thermal substrate deposition method (TSD). In the frame of this work, the TSD method was at first applied for obtaining ZnO coating from aqueous alginate-containing and alginate-free solutions on a metal surface. XRD, SEM analyses show that the biopolymer has a significant influence on the formation of the coating, their morphology, texture, structure of ZnO nanoparticles. The average rate of ZnO deposition from alginate containing solution is 30 μm/min, while from alginate-free solutions – 6 μm/min. In the presence of alginate, spherical particles with flower-shaped inclusions are formed, while from the polymer-free solution, single crystals in the form of tetrahedral were obtained. Zone of inhibition test against Gram-positive S. aureus ATCC 25923 and Gram-negative E. coli ATCC 25922 proves the antibacterial activity of the ZnO/Alg coatings.

Objective. To investigate the impact of the sorbtion-aspiration drainage system on background of hydroxyapatite and zinc oxide on experimental peritonitis. Materials and methods. The experiment was performed on 55 white laboratory rat males, ageing 2 - 3 mo, with the body mass 225 - 250 g, which were kept in the typical vivarium conditions. Suspension of E. coli in physiological solution, 1.0 - 1.5 ml in concentration 1010 , was used for the peritoneum contamination. The suspension was introduced into abdominal cavity in the dose, dependent on the animal body mass, using the syringe for insulin injection. Peritonitis in the rats was developed in 48 h and characterized by intoxication, which exaggerated rapidly, as well as by intestinal motor disorders and pronounced microcirculatory disturbances. The experimental animals were distributed into 5 Groups. In patients of Group I the interventions were not performed (control); in laboratory animals of Group II peritonitis was not simulated, but the abdominal cavity was drained, using the sorption-aspiration drainage system; in laboratory animals of Group III peritonitis was simulated; in the Group IV of laboratory animals on background of peritonitis the abdominal cavity was drained, using the sorption-aspiration drainage system; in the Group V animals the abdominal cavity was drained by a standard silicon drain on background of peritonitis. Results. Reduction of abdominal contamination by 43.12% and of histological features were produced in abdominal organs under the influence of the composite system, witnessing its bactericidal and sorption-antiinflammatory action. Conclusion. Experimentally there was confirmed the possibility of application of sorption-aspiration drainage system on background of hydroxyapatite and zinc oxide in treatment of an acute peritonitis.

In Eastern Europe countries, including Ukraine, a significant part of the buildings belongs to the mass development of the 80s, which are characterized by a low level of energy efficiency. For such countries with sharply continental climates, heating costs prevail to a large extent. Improved thermal protection forces more attention to be paid to heat losses with ventilation. The distribution of air exchange between individual rooms is difficult to determine, especially due to natural ventilation. The work is devoted to considering the conditions of natural convection and determining the effect on the energy consumption of a building. The article considers the advanced ASHRAE technique for calculating natural air exchange. The influence of the temperature and wind characteristics of the outdoor air on the natural component of the air exchange rate at the different locations of the representative rooms of an 8-story building is analyzed. The value of the air exchange rate for typical conditions of Kiev does not exceed 0.25 h-1, 0.65 h-1 and 0.4 h-1 for two-chamber and single-chamber double-glazed windows, triple glazing in wooden double binders, respectively. On the first floors, air exchange is associated with air infiltration, and on the last floors there is exfiltration, which must be taken into account when dynamically modeling the energy characteristics of a building. The example is with additional mechanical ventilation to maintain a comfortable environment. 5R1C dynamic grid models were created to study the energy performance of the building. The estimate of additional heating costs due to infiltration is 23 % for the North and 43 % for the South orientation of rooms with two-chamber energy-saving windows. It has been established that in dynamics, the energy consumption of a building with normative air exchange and the calculated value of the natural component differs by 50–75 %, which is a possible level of savings under actual air exchange conditions in comparison with standard ones. This savings can be reduced by increasing air exchange during busy hours, for example, due to additional aeration.

Some recent studies associated insulin therapy with negative cardiovascular events and shorter lifespan. SUR2A, a KATP channel subunit, regulate cardioprotection and cardiac ageing. Here, we have tested whether glucose and insulin regulate expression of SUR2A/KATP channel subunits and resistance to metabolic stress in heart H9c2 cells. Absence of glucose in culture media decreased SUR2A mRNA, while mRNAs of Kir6.2, Kir6.1, SUR1 and IES SUR2B were increased. 2-deoxyglucose (50 mM) decreased mRNAs of SUR2A, SUR2B and SUR1, did not affect IES SUR2A and IES SUR2B mRNAs and increased Kir6.2 mRNA. No glucose and 2-deoxyglucose (50 mM) decreased resistance to an inhibitor of oxidative phosphorylation, DNP (10 mM). 50 mM glucose did not alter KATP channel subunits nor cellular resistance to DNP (10 mM). Insulin (20 ng/ml) in both physiological and high glucose (50 mM) down-regulated SUR2A while upregulating Kir6.1 and Kir6.2 (in high glucose only). Insulin (20 ng/ml) in physiological and high glucose decreased cell survival in DNP (10 mM). As opposed to Kir6.2, infection with SUR2A resulted in titre-dependent cytoprotection. We conclude that insulin decreases resistance to metabolic stress in H9c2 cells by decreasing SUR2A expression. Lower cardiac SUR2A levels underlie increased myocardial susceptibility to metabolic stress and shorter lifespan. Keywords: Insulin, Glucose, SUR2A, Heart

Abstract Background C60 fullerene-based nanoformulations are proposed to have a direct toxic effect on tumor cells. Previous investigations demonstrated that C60 fullerene used alone or being conjugated with chemotherapeutic agents possesses a potent anticancer activity. The main aim of this study was to investigate the effect of C60 fullerene and its nanocomplexes with anticancer drugs on human phagocyte metabolic profile in vitro. Methods Analysis of the metabolic profile of phagocytes exposed to C60 fullerene in vitro revealed augmented phagocytic activity and down-regulated reactive nitrogen species generation in these cells. Additionally, cytofluorimetric analysis showed that C60 fullerene can exert direct cytotoxic effect on normal and transformed phagocytes through the vigorous induction of intracellular reactive oxygen species generation. Results Cytotoxic action as well as the pro-oxidant effect of C60 fullerene was more pronounced toward malignant phagocytes. At the same time, C60 fullerenes have the ability to down-regulate the pro-oxidant effect of cisplatin on normal cells. These results indicate that C60 fullerenes may influence phagocyte metabolism and have both pro-oxidant and antioxidant properties. Conclusions The antineoplastic effect of C60 fullerene has been observed by direct toxic effect on tumor cells, as well as through the modulation of the functions of effector cells of antitumor immunity.

Abstract BslA is a protein secreted by Bacillus subtilis which forms a hydrophobic film that coats the biofilm surface and renders it water-repellent. We have characterised three orthologues of BslA from Bacillus amyloliquefaciens, Bacillus licheniformis and Bacillus pumilus as well as a paralogue from B. subtilis called YweA. We find that the three orthologous proteins can substitute for BslA in B. subtilis and confer a degree of protection, whereas YweA cannot. The degree to which the proteins functionally substitute for native BslA correlates with their in vitro biophysical properties. Our results demonstrate the use of naturally-evolved variants to provide a framework for teasing out the molecular basis of interfacial self-assembly.