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The amount of antibiotics has increased over the past decade. This also resulted in increase of microorganisms’ resistance to this class of drugs. Therefore, the synthesis of new compounds that have exhibited antimicrobial and antifungal activity and low level of side effects is an important issue of modern pharmacy. The 1,2,4-triazole system is very promising in this aspect. The aim was to study the antimicrobial and antifungal activity of 4-R-5-(thiophen-2-ylmethyl)-4H-1,2,4-triazole-3-thiol and 3-(alkylthio)-4-R-5-(thiophen-2-ylmethyl)-4H-1,2,4-triazole. Methods and results. In the study "serial dilutions" method has been used. The criteria for the activity of given compound was the minimum inhibitory concentration (MIC) which is the lowest concentration of drug that inhibits the growth of the test culture and the minimum bactericidal concentration (MBC) which is the lowest concentration of drug that causes bactericidal effect. Test compounds are derivatives of 4-R-5-(thiophen-2-ylmethyl)-4H-1,2,4-triazole-3-thiol and 3-(alkyl-thio)-4-R-5-(thiophene-2-ylmethyl)-4H-1,2,4-triazole which exhibit antifungal and antimicrobial activity. Conclusion. The most active of the studied 1,2,4-triazole derivatives is 4 (4-methyl-3-(octylthio)-5-(thiophen-2-ylmethyl)-4H-1,2,4-triazole), which manifests as antifungal and antimicrobial activity. Some regularity between structure and action has been investigated.

The microbial reduction of sulfate to sulfide coupled to organic matter oxidation followed by the transformation of sulfide back to sulfate drives a dynamic sulfur cycle in a variety of environments. The oxidative part of the sulfur cycle in particular is difficult to constrain because the eight electron oxidation of sulfide to sulfate occurs stepwise via a suite of biological and chemical pathways and produces a wide variety of intermediates (Sx2-, S0, S2O32-, S4O62-, and SO32-), which may in turn be oxidized, reduced or disproportionated. Although the potential processes affecting these intermediates are well-known from microbial culture and geochemical studies, their significance and rates in the environment are not well constrained. In the study presented here, time-course concentration measurements of intermediate sulfur species were made in amended freshwater water column and sediment incubation experiments in order to constrain consumption rates and processes. In sediment incubations, consumption rates were Scolloidal0>Sx2->SO32-≈ S4O62-> S2O32-, which is consistent with previous measurements of SO32-, S4O62-, and S2O32- consumption rates in marine sediments. In water column incubations, however, the relative reactivity was Scolloidal0>SO32->Sx2-> S2O32-> S4O62-. Consumption of thiosulfate, tetrathionate and sulfite was primarily biological, whereas it was not possible to distinguish between abiotic and biological polysulfide consumption in either aqueous or sediment incubations. Scolloidal0 consumption in water column experiments was biologically mediated, however, rapid sedimentary consumption was likely due to reactions with iron minerals. These experiments provide important constraints on the biogeochemical reactivity of intermediate sulfur species and give further insight into the diversity of biological and geochemical processes that comprise (cryptic) environmental sulfur cycling.

За допомогою молекулярно-генетичних та імунофлюоресцентних методів досліджували вплив гестаційного діабету на рівень експресії мРНК автоімунного регулятора Аire та характер диференціювання Foxp3+-клітин в брижових лімфатичних вузлах у нащадків щурів лінії Wistar. У нащадків щурів з експериментальним гестаційним діабетом виявлено зниження вмісту в клітинах брижових лімфатичних вузлів мРНК автоімунного регулятора Aire в 2,3-8,1 рази (p

Background. Formation of immunological tolerance to self-antigens is an important mechanism that prevents development of the autoimmune diseases. Objective. With the help of molecular genetic and immunofluorescence techniques to investigate the effects of experimental gestational diabetes on the level of mRNA expression of autoimmune regulator Aire and differentiation features of Foxp3+ cells in mesenteric lymph nodes in the offspring of Wistar rats. Methods. To determine the level of Аire mRNA RT-PCR was performed in real-time by thermocycler CFX96™ Real-Time PCR Detection Systems («Bio-RadLaboratories, Inc», USA). The relative level of gene expression were studied with rat reference genes GAPDH by the method ΔΔCt. Statistical analysis were conducted using available software «Bio-Rad СFX Manager 3.1» (Bio-Rad, USA). The immunopositive Foxp3+-lymphocytes were determined using an indirect immunofluorescence technique with using a monoclonal rat antibody. Results. The offspring of experimental gestational diabetes rats showed the reduction of autoimmune regulator Aire mRNA in 2,3-8,1 times (p

Despite the wide application of brand-new instruments, continuous improvements in surgical treatment and application of up-to-date antiseptics and disinfectants within the last decade,a risk of infectious complications inhip and knee jointsendoprosthesis replacementstill remains.The most efficient results in post-surgery implant-related infection (IRI) treatment are attained when combining surgical interference with long-term etiotropic therapy, its efficiency being evaluated via balanced selection of antimicrobialagents. “Perfect” antibacterial drug for surgical infection treatment must reveal bactericidal effect against specific infectious agents, form high concentrations in bones, joints and soft tissues and have high safety profile. The challenge is that currently for most part of antibiotics there is no convincing evidence in regards to their application for implant-related infection (IRI). At present it is generally accepted that the leading role of S. Aureus and S. Epidermidis in IRI etiology is largely due to their ability to generate multi-level microbial biofilms quickly at the artificial implants surface. Pathogens’ presence in biofilms makes IRI diagnostics more complicated and significantly reduces the efficiency of antimicrobial therapy. Earlier it has been determined that 1.8-disubstituted of theobromine show rather high diuretic, anti-inflammatory, analgesic, antioxidant, hypolipidemic and antimicrobial activity. Thus, the problem of discovering new highly efficient antimicrobial agents which might be applied in IRI treatment remains relevant and long-termissue. Aim of the work is to develop simple laboratory methods to synthesize 8- benzylidenhydrazino-1-n-propyltheobromines and study biological activity of synthesized compounds. Materials and Methods of Research Themeltingpointhasbeendeterminedwiththehelpofanopencapillary methodwithTAPdevice(M).Elementalanalysishasbeenperformedwiththe help of the instrument ElementarVario L cube, NMR-spectra have been taken on a spectrometer Bruker SF-200 (operating frequency of 200 MHz, solvent DMSO, internal standard – TMS). These data correspond to thecalculated elemental analysis.For the initial screening study of the new synthesized substances there has been usedthebenchmarkscultureasgram-positiveandgram-negativebacteriawhich belongtodifferentmorphologicalpropertiesofclinicallyimportantgroupsof infectiousagents.AsasetofstandardteststrainswehavetakenEscherichiacoli ATSS 25922, Staphylococcus aureus ATSS 25923, Pseudomonas aeruginosa ATSS27853, Candida albicans ATSS 885-653. All test strains have been obtained from thelaboratorycalled"ZaporizhzhyaRegionalLaboratoryCenteroftheState epidemiological station of Ukraine." The sensitivity of microorganisms to promising antimicrobialnewsynthesizedsubstanceshasbeendeterminedaccordingtothe guidelines.Duringthestudiestherehavebeenpreparedtheserialtwo-fold dilutions of the drug in Mueller-Hinton broth in a volume of 1 ml, and then added to each tube 0.1 ml of microbial curtain (106 CFU / ml). We havedeterminedtheminimuminhibitoryconcentration(MIC).Asthe solvent compounds we have used dimethylsulfoxidein the studies, the initial solution hasbeenadjustedtoaconcentrationof1mg/ml.Additionallywehaveheldthe control of culture media and solvent by the conventional methods. Results Heating of 8-bromo-1-n-propyltheobromine with an excess of hydrazine hydrate in aqueous dioxane leads to the formation of 8-hydrazino-1-n-propyltheobromine. Interaction of 8-hydrazinoptheobromine with aldehydes has lead to formation of a range of respective 8-benzylidenhydrazinoderivatives. Structure of synthesized compounds has been definitely proved by NMR-spectroscopy.It has beenfound, that synthesized 8-benzylidenhydrazino-1-n-propyltheobrominesexhibit mild effect.Index of antibacterial activity of some compoundsagainstStaphylococcus aureus and Candida albicans is approaching toAmpicillin andNystatin. Conclusion Suggesting laboratory method to obtain 8-hydrazino-1-n-propyltheobromine, initial synthon for further xanthine molecule modification. Developing accessible laboratory methods to synthesize new 8-benzylidenhydrazino-1-n-propyltheobromines, which are potential bioactive compounds. Studying PMR-spectral characteristics of the obtained substances. Conducting primary screening research of antimicrobial activity of 8- benzylidenhydrazine derivatives, which revealed viability of further search for antistaphylococcal and antifungal drugs within this range.

The Gulf of Aqaba is an oligotrophic marine system with oxygen-rich water column and organic carbon-poor sediments (≤0.6% at sites that are not influenced by anthropogenic impact). Aeolian dust deposition from the Arabian, Sinai, and Sahara Deserts is an important source of sediment, especially at the deep-water sites of the Gulf, which are less affected by sediment transport from the Arava Desert during seasonal flash floods. Microbial sulfate reduction in sediments is inferred from the presence of pyrite (although at relatively low concentrations), the presence of sulfide oxidation intermediates, and by the sulfur isotopic composition of sulfate and solid-phase sulfides. Saharan dust is characterized by high amounts of iron minerals such as hematite and goethite. We demonstrated, that the resulting high sedimentary content of reactive iron(III) (hydr)oxides, originating from this aeolian dry deposition of desert dust, leads to fast re-oxidation of hydrogen sulfide produced during microbial sulfate reduction and limits preservation of reduced sulfur in the form of pyrite. We conclude that at these sites the sedimentary sulfur cycle may be defined as cryptic.

Introduction. This work is a follow-up to a series of research activities dedicated to the search of biologically active compounds among the xanthine derivatives. Aim of the Work.Development of simple laboratory-based methods for 8-amino-1-p-chlorobenzyltheobromines synthesis and the study of antioxidant, antimicrobial and antifungal effect of the synthesized compounds. Materials and Methods of Research.The melting point has been determined with the help of an open capillary method with TAP device (M). Elemental analysis has been performed with the helpof the instrument ElementarVario L cube, NMR-spectra have been taken on a spectrometer Bruker SF-400 (operating frequency of 400 MHz, solvent DMSO-d6 or DMSO-d6 + CDCl3, internal standard – TMS). These data correspond to thecalculated elemental analysis. The synthesis of 8-aminosubstituted 1-p-chlorobenzyltheobromine (2,3).Mixture 0.01 mole of8-bromo-1-p-chlorobenzyltheobromine (1), 0.03 mole of pyrrolidine (2) or piperidine (3), 40 ml of cellosolve is boiled during 4 hours, then it is allowed to steam out dry in a vacuum. Dry residue is processed with water, then residual matter which has been formed is filtered out, washed with water and recrystallized from the aqueous ethanol. The synthesis of 8-amino-1-p-chlorobenzyltheobromines (4-7). Mixture 0.01 mole of initial compound (1), 0.03 mole of the respective amine and 40 ml of cellosolve is boiled during 4 hours, thenit is allowed to cool down and is diluted with water. After this, residual matter which has been formed is filtered out, washed with water and aqueous propanol-2 and recrystallized from the water ethanol. Molecular descriptors have been calculated using the computer programs ALOGPS and DRAGON, whereas biological properties of the synthesized compounds have been calculated with the help of GUSAR and ACD / Percepta Platform. Antioxidant activity (AOA) has been studied in vitro applying the method of nonenzymic initiation of free-radicaloxidation. For the initial screening study of the newly-synthesized substances benchmark testing-cultures of both gram-positive and gram-negative bacteria have been used, which belong to clinically significant groups of infectious agents which are differing by their morpho-physiological properties,. Results and their discussion. Through the reaction of 8-bromo-1-p-chlorobenzyltheobromine with secondary heterocyclic amines (pyrrolidine, morpholine, hexamethylenimine, piperidine and its derivatives) in cellosolve environment a range of 8-heteryle-substituted (2-7) has been obtained which was not described earlier. All the obtained compounds satisfy to the Lipinski's ‘rule of five’, which proves the viability of further research activities. The application of ACD/Percepta Platform has allowed to calculate the absorption characteristics, permeability via blood-brain barrier, as well as establish probable transport forms of blood of the synthesized compounds. Assisted by computer programs GUSAR and ACD / Percepta Platform, further on there has been calculated the acute toxicity rate for rats and mice. Among the synthesized substances, 8-(hexahydroazepin-1-yl)-1-p-chlorobenzyltheobromine (6) has appeared to be the most active antioxidant, being more active than tiotriazolini while ranking below the ascorbic acid as per this indicator. It has beenfound, that among the synthesized 8-aminosubstituted 1-p-chlorobenzyltheobromine there is no evidence of prospective compounds with antibacterial activity in reference to E. coli, S. aureus and P. aeruginosa. Conclusion. There have been developed available laboratory-based methods for the synthesis of 8-aminosubstituted 1-p-chlorobenzyltheobromine, the structure of which has been proved by data obtained from elemental analysis and NMR- spectroscopy. Molecular (LogP, TPSA, A) and pharmaceutical (Pe, Ka, PPB, LogKaHSA, LogPS, LogPB, Log(PS*fu)) descriptors have been calculated for forecasting the properties of obtained substances. Acute toxicity indexhas been calculated too. Finally, antioxidant, antimicrobial and antifungal effect of the synthesized compounds has been studied and priorities for further search of biologically active compounds have been set out.

4D printing is based on 3D printing of objects that can change their shape upon a proper triggering. Here, a novel approach is reported for fabricating programmable 3D printed objects composed of shape‐memory polymers (SMPs) that are activated by light. The light activation of the movement and shape morphing are based on combining gold nanoparticles (AuNPs) as photothermal converters with acrylate‐based printing compositions that form an SMP with tunable transition temperatures. The shape change of the printed objects is triggered by remote irradiation with a low‐cost LED light at a wavelength specific to the surface plasmon resonance of the embedded AuNPs. The light is converted to heat which enables the shape transition when the temperature reaches the Tg of the polymer. Excellent SMP properties are achieved with shape fixity and recovery ratios over 95%. This material composition and triggering approach enable fabricating programmable light‐activated 3D printed structures with a dual transition while tuning the concentration. Furthermore, numerical simulations performed by finite‐element analysis result in the excellent prediction of the shape‐memory recovery. The presented approach can be applied in remotely controlling morphing, mainly for applications in the fields of actuators and soft robotics. [ABSTRACT FROM AUTHOR]

The examination of 107 children in the first year of life — residents of large industrial cities and 184 children from mid-sized cities has been carried out. It is proved that more significant dysbiotic disorders that are characterized by decrease in the amount of normal symbionts and increase the number of opportunistic pathogens in the gut are detected in children who live in ecologically unfavorable regions are. The necessity of prophylactic use of probiotics to mitigate the impact of living in an industrial city in impossibility of breastfeeding was substantiated.

In the past few years, the synthesis of Cu nanoparticles has attracted much attention because of its huge potential for replacing expensive nano silver inks utilized in conductive printing. A major problem in utilizing these copper nanoparticles is their inherent tendency to oxidize in ambient conditions. Recently, there have been several reports presenting various approaches which demonstrate that copper nanoparticles can resist oxidation under ambient conditions, if they are coated by a proper protective layer. This layer may consist of an organic polymer, alkene chains, amorphous carbon or graphenes, or inorganic materials such as silica, or an inert metal. Such coated copper nanoparticles enable achieving high conductivities by direct printing of conductive patterns. These approaches open new possibilities in printed electronics, for example by using copper based inkjet inks to form various devices such as solar cells, Radio Frequency Identification (RFID) tags, and electroluminescence devices. This paper provides a review on the synthesis of copper nanoparticles, mainly by wet chemistry routes, and their utilization in printed electronics.

The problem of investigation of molecular mechanisms of apoptosis and its role in autoimmune disease, includingdiabetes mellitus, became one of the most difficult and actual among the medical sciences last years. Under the experimentthe effect of experimental diabetes mellitus on the intensity of protein expression of apoptotic regulators Bcl-2 and p53 in thespleen of rats was investigated. To detect Bcl-2 and p53 positive-cells we used immunohistochemical technique of indirectimmunofluorescence with monoclonal antibodies to Bcl-2 and p53. It was found that the development of experimentaldiabetes mellitus is accompanied by unidirectional tendency to increase the number of p53- and Bcl-2-positive cells inlymphoid follicles of the spleen with a preferential decrease in the concentration of these protein in immune cells.

Peculiarities of protein р53 expression in rat thymus with experimental diabetes mellitus were investigated and discussed in experimental work. Investigations were carried out on 28 male rats Vistar line 5-6 months of age. Experimental diabetes mellitus was designed by intraperitoneal injection of streptozotocyn (SIGMA, USA) at dose 50 mg/kg one time. Method of double immunofluorescence with usage of rat monoclonal anti-p53 and anti-СD4 antibodies was used for revelation of p53. Structure of a thymus was analyzed with the help of software VIDAS. Control animals showed an increase of p53+-cells quantity in thymus cortical zone by 58% as compared with medullar zone. Even so immature forms of p53+-cells – big lym-phocytes and p53+-lymphoblasts prevailed in population of p53+-cells of both thymus cortical zone and medullar zone. It has been established that development of experimental diabetes mellitus was accompanied by increase in number of p53+-cells and concentration of protein р53 in thymus cortical zone in the absence of any changes in medullar zone.

Environmental context: The quality of drinking water can be greatly compromised by the presence of dimethyl polysulfides. We studied the rate and mechanism of decomposition of dimethyl polysulfides in aqueous solution under solar irradiation, and found that they decompose photochemically in seconds to minutes, i.e. much faster than under dark conditions. These results suggest that photochemical pathways of dimethyl polysulfide decomposition may prevail in euphotic zones of natural aquatic systems. The presence of malodorous dimethyl polysulfides (DMPSs) has been documented in marine and limnic systems as well as in tap water distribution systems. These compounds compromise the quality of drinking water. Under oxic conditions and in the absence of radiation, DMPSs with n ≥ 3 sulfur atoms disproportionate into DMPSs with n + 1 and n − 1 sulfur atoms, and, finally, to dimethyl disulfide (DMDS) and S8. DMDS, in turn, decomposes to methyl mercaptan (MT) and methanesulfinic acid. Under these conditions, the half-lives of DMPSs vary from months for dimethyl pentasulfide (DM5S) to hundreds of thousands of years for DMDS. In this work, we studied the kinetics and mechanisms of the decomposition reactions of DMPSs with 2–5 sulfur atoms in aqueous solutions in the presence of oxygen and under exposure to solar radiation. The quantum yields of decomposition of DMPSs with 2, 3, 4 and 5 sulfur atoms do not depend on either the concentration of DMPSs or pH, and are 40 ± 10, 2.0 ± 0.2, 35 ± 10 and 10 ± 4 respectively. The quantum yields, which are higher than unity, suggest that under exposure to solar radiation the photochemical decomposition of DMPSs proceeds by a radical chain reaction mechanism. Half-lives of DMPSs in oxic aquatic solutions exposed to solar radiation under a very clear atmosphere and a solar elevation angle of 90 ° were calculated from the quantum yields and were found to be as low as 43 ± 13 s for DMDS, 40 ± 4 s for dimethyl trisulfide (DMTS), 2.1 ± 0.6 s for dimethyl tetrasulfide (DM4S) and 4.2 ± 1.7 s for DM5S. Environmental context. The quality of drinking water can be greatly compromised by the presence of dimethyl polysulfides. We studied the rate and mechanism of decomposition of dimethyl polysulfides in aqueous solution under solar irradiation, and found that they decompose photochemically in seconds to minutes, i.e. much faster than under dark conditions. These results suggest that photochemical pathways of dimethyl polysulfide decomposition may prevail in euphotic zones of natural aquatic systems. [ABSTRACT FROM AUTHOR]