4-Allyl-3-(2-methyl-4-quinol­yl)-1H-1,2,4-triazole-5(4H)-thione

In the title compound, C15H14N4S, the quinoline and triazole rings form a dihedral angle of 41.48 (7)°. In the crystal, adjacent mol­ecules are linked by N—H⋯N hydrogen bonds, forming chains along [100]

Identification and characterization of antibacterial compound(s) of cockroaches (Periplaneta americana)

Infectious diseases remain a significant threat to human health, contributing to more than 17 million deaths, annually. With the worsening trends of drug resistance, there is a need for newer and more powerful antimicrobial agents. We hypothesized that animals living in polluted environments are potential source of antimicrobials. Under polluted milieus, organisms such as cockroaches encounter different types of microbes, including superbugs. Such creatures survive the onslaught of superbugs and are able to ward off disease by producing antimicrobial substances. Here, we characterized antibacterial properties in extracts of various body organs of cockroaches (Periplaneta americana) and showed potent antibacterial activity in crude brain extract against methicillin-resistant Staphylococcus aureus and neuropathogenic E. coli K1. The size-exclusion spin columns revealed that the active compound(s) are less than 10 kDa in molecular mass. Using cytotoxicity assays, it was observed that pre-treatment of bacteria with lysates inhibited bacteria-mediated host cell cytotoxicity. Using spectra obtained with LC-MS on Agilent 1290 infinity liquid chromatograph, coupled with an Agilent 6460 triple quadruple mass spectrometer, tissues lysates were analyzed. Among hundreds of compounds, only a few homologous compounds were identified that contained isoquinoline group, chromene derivatives, thiazine groups, imidazoles, pyrrole containing analogs, sulfonamides, furanones, flavanones, and known to possess broad-spectrum antimicrobial properties, and possess anti-inflammatory, anti-tumour, and analgesic properties. Further identification, characterization and functional studies using individual compounds can act as a breakthrough in developing novel therapeutics against various pathogens including superbugs

Chemical and environmental assessment of the bottom sediments in the Irtysh River (Tyumen Region, Russian Federation)

The total concentration of Al, Co, Fe, Mn, Pb, Cu, Zn, Sr, As, Cr, Ni has been determined in the test portions of the bottom sediments (sand, loamy sand, sandy loam, silt and clay loam) in the lower reach of the Irtysh River. Atomic emission spectroscopy has been used. The established concentrations do not exceed background indicators, except for Pb and As. Their maximum values are 138 and 7.2 mg/kg, respectively. Gross concentrations of metals and metalloids are in close correlation with the content of various particle size fractions in the river sediments. Emission status of the bottom sediments has been analyzed with account of particle-size classification. As a result, multiple regression equations have been obtained. The equations reflect mathematical relationship between concentration of different elements and two regressors – the proportion of clay and silt particles in the bottom sediments of the Irtysh River. Based on these equations and determining the percentage of various particle-size fractions in soils, it is possible to predict the most probable amount of the metal concentration in the test portion. The content of oil products in bottom sediments of the river has been determined by IR spectrometry. The concentration of oil products in 24 % of test portions does not exceed the maximum permissible limit equal to 20 mg/kg. The concentration of oil products varies from 21 to 73 mg/kg in the remaining test portions of the bottom sediments. The statistically significant correlations of the gross concentrations of elements with iron, manganese, organic substance and oil products in the bottom sediments of the lower reach of the Irtysh River have been revealed. The weak statistically significant pH correlations with indicators of the particle-size classification of bottom sediments have been determine

Unveiling the Role of Iron in the Nickel-Catalyzed Urea Oxidation Reaction

The electrochemical urea oxidation reaction (UOR) on Ni has recently attracted much attention as part of the global effort to produce hydrogen from waste. Fe addition to Ni (hydro)oxides results in a significant enhancement of the rate of the oxygen evolution reaction (OER), and a similar role of Fe in the UOR has often been claimed. In this work, we explore the influence of Fe3+ ions in the electrolyte on the alkaline UOR on Ni. To this end, we systematically increase the concentration of the Fe3+ ions in NaOH and incorporate them in the Ni(OH)2 layer grown on the electrode by electrochemical potential cycling. We then determine the fraction of Fe on the Ni(OH)2 surface by X-ray photoelectron spectroscopy and investigate the UOR by cyclic voltammetry and Fourier transform infrared spectroscopy (FTIRS) depending on the Fe fraction. We conclude that contrary to the OER, the presence of Fe is detrimental for the UOR. We then discuss the influence of the potential and Fe on the product distribution revealed by FTIRS

Formation of Micro- and Nanostructures on the Nanotitanium Surface by Chemical Etching and Deposition of Titania Films by Atomic Layer Deposition (ALD)

In this study, an integrated approach was used for the preparation of a nanotitanium-based bioactive material. The integrated approach included three methods: severe plastic deformation (SPD), chemical etching and atomic layer deposition (ALD). For the first time, it was experimentally shown that the nature of the etching medium (acidic or basic Piranha solutions) and the etching time have a significant qualitative impact on the nanotitanium surface structure both at the nano- and microscale. The etched samples were coated with crystalline biocompatible TiO2 films with a thickness of 20 nm by Atomic Layer Deposition (ALD). Comparative study of the adhesive and spreading properties of human osteoblasts MG-63 has demonstrated that presence of nano- and microscale structures and crystalline titanium oxide on the surface of nanotitanium improve bioactive properties of the material

Modification of the Surface Topography and Composition of Ultrafine and Coarse Grained Titanium by Chemical Etching

In this study, we present the detailed investigation of the influence of the etching medium (acidic or basic Piranha solutions) and the etching time on the morphology and surface relief of ultrafine grained (UFG) and coarse grained (CG) titanium. The surface relief and morphology have been studied by means of scanning electron microscopy (SEM), atomic force microscopy (AFM), and the spectral ellipsometry. The composition of the samples has been determined by X-ray fluorescence analysis (XRF) and X-ray Photoelectron Spectroscopy (XPS). Significant difference in the etching behavior of UFG and CG titanium has been found. UFG titanium exhibits higher etching activity independently of the etching medium. Formed structures possess higher homogeneity. The variation of the etching medium and time leads to micro-, nano-, or hierarchical micro/nanostructures on the surface. Significant difference has been found between surface composition for UFG titanium etched in basic and acidic Piranha solution. Based on the experimental data, the possible reasons and mechanisms are considered for the formation of nano- and microstructures. The prospects of etched UFG titanium as the material for implants are discussed