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41.
Viktoria M. Zemtsova Alexey Yu. Fedorov Elizaveta A. Fedorova Callum Boa Sergey G. Arkhipov Denis A. Rychkov Vasily S. Minkov Colin R. Pulham Elena V. Boldyreva 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(11):1465-1470
We report the crystal structure and crystallization conditions of a first hydrated form of metacetamol (a hemihydrate), C8H9NO2·0.5H2O. It crystallizes from metacetamol‐saturated 1:1 (v/v) water–ethanol solutions in a monoclinic structure (space group P21/n) and contains eight metacetamol and four water molecules per unit cell. The conformations of the molecules are the same as in polymorph II of metacetamol, which ensures the formation of hydrogen‐bonded dimers and R22(16) ring motifs in its crystal structure similar to those in polymorph II. Unlike in form II, however, these dimers in the hemihydrate are connected through water molecules into infinite hydrogen‐bonded molecular chains. Different chains are linked to each other by metacetamol–water and metacetamol–metacetamol hydrogen bonds, the latter type being also present in polymorph I. The overall noncovalent network of the hemihydrate is well developed and several types of hydrogen bonds are responsible for its formation. 相似文献
42.
Ekaterina S. Babich Elizaveta S. Gangrskaia Igor V. Reduto Jérémie Béal Alexey V. Redkov Thomas Maurer Andrey A. Lipovskii 《Current Applied Physics》2019,19(10):1088-1095
A simple technique to fabricate microchannels in glasses with self-assembled silver nanoparticles (NPs) in the channels is presented. It combines thermal-electric poling of silver-to-sodium ion-exchanged glass slides with a patterned anodic electrode, formation of the microchannels via selective etching off the unpoled slide regions, and hydrogen annealing. The annealing results in the growth of NPs only on the bottom of the channels. The studies performed allowed optimizing the channels’ depth and NPs surface density for Surface Enhanced Raman Scattering (SERS) based sensing and microfluidic applications. We have demonstrated that the formed NPs allow detection of 1/20 of BPE (1,2-Di(4-pyridyl)ethylene 97%) monolayer, the evaluated Raman enhancement factor being ~4·107. The proposed approach based on the glass poling allowed us the fabrication of ~1 μm deep channels and easy multiplication of the structures because the anodic electrodes used for the poling are capable of multiple usage. 相似文献
43.
Petr Jaro Elizaveta Timkina Jana Michailidu Dominik Marík Markta Kuliov Irena Kolouchov Kateina Demnerov 《Molecules (Basel, Switzerland)》2022,27(12)
Boswellic acids are biologically active pentacyclic terpenoid compounds derived from Boswellia sp. plants. Extracts containing these acids have a number of positive effects on human health, especially in the treatment of inflammation, arthritis, or asthma. With increasing resistance to common antibiotics, boswellic acid-containing extracts could serve as an alternative or work in synergy with commonly available preparations. This study aims to determine the effect of boswellic acids on suspension cells and biofilms of Staphylococcus epidermidis, Enterococcus faecalis, and Escherichia coli. The antimicrobial and antibiofilm effect found was compared with commonly available antibiotics to control these undesirable microorganisms. The synergistic effect of boswellic acids and common antibiotics on the growth of these microorganisms was also determined. All tested microorganisms showed a positive additive effect of antibiotics and boswellic acid extract. The most significant effect was found in Enterococcus faecalis ATCC 29212 in a combination of 0.2 × MIC80 erythromycin (0.2 mg/L) and 0.8 × MIC80 boswellic acid extract (16 mg/L). 相似文献
44.
Anton M. Manakhov Elizaveta S. Permyakova Natalya A. Sitnikova Alphiya R. Tsygankova Alexander Y. Alekseev Maria V. Solomatina Victor S. Baidyshev Zakhar I. Popov Lucie Blahov Marek Eli Lenka Zají
kov Andrey M. Kovalskii Alexander N. Sheveyko Philipp V. Kiryukhantsev-Korneev Dmitry V. Shtansky David Ne
as Anastasiya O. Solovieva 《Molecules (Basel, Switzerland)》2022,27(4)
The COVID-19 pandemic has raised the problem of efficient, low-cost materials enabling the effective protection of people from viruses transmitted through the air or via surfaces. Nanofibers can be a great candidate for efficient air filtration due to their structure, although they cannot protect from viruses. In this work, we prepared a wide range of nanofibrous biodegradable samples containing Ag (up to 0.6 at.%) and Cu (up to 20.4 at.%) exhibiting various wettability. By adjusting the magnetron current (0.3 A) and implanter voltage (5 kV), the deposition of TiO2 and Ag+ implantation into PCL/PEO nanofibers was optimized in order to achieve implantation of Ag+ without damaging the nanofibrous structure of the PCL/PEO. The optimal conditions to implant silver were achieved for the PCL-Ti0.3-Ag-5kV sample. The coating of PCL nanofibers by a Cu layer was successfully realized by magnetron sputtering. The antiviral activity evaluated by widely used methodology involving the cultivation of VeroE6 cells was the highest for PCL-Cu and PCL-COOH, where the VeroE6 viability was 73.1 and 68.1%, respectively, which is significantly higher compared to SARS-CoV-2 samples without self-sanitizing (42.8%). Interestingly, the samples with implanted silver and TiO2 exhibited no antiviral effect. This difference between Cu and Ag containing nanofibers might be related to the different concentrations of ions released from the samples: 80 μg/L/day for Cu2+ versus 15 µg/L/day for Ag+. The high antiviral activity of PCL-Cu opens up an exciting opportunity to prepare low-cost self-sanitizing surfaces for anti-SARS-CoV-2 protection and can be essential for air filtration application and facemasks. The rough cost estimation for the production of a biodegradable nanohybrid PCL-Cu facemask revealed ~$0.28/piece, and the business case for the production of these facemasks would be highly positive, with an Internal Rate of Return of 34%. 相似文献
45.
Rebecca Vande Voorde Elizaveta Dzalamidze Dylan Nelson Lia Danelishvili 《Molecules (Basel, Switzerland)》2022,27(18)
Mycobacterial pathogens are intrinsically resistant to many available antibiotics, making treatment extremely challenging, especially in immunocompromised individuals and patients with underlying and chronic lung conditions. Even with lengthy therapy and the use of a combination of antibiotics, clinical success for non-tuberculous mycobacteria (NTM) is achieved in fewer than half of the cases. The need for novel antibiotics that are effective against NTM is urgent. To identify such new compounds, a whole cell high-throughput screen (HTS) was performed in this study. Compounds from the Chembridge DIVERSet library were tested for their ability to inhibit intracellular survival of M. avium subsp. hominissuis (MAH) expressing dtTomato protein, using fluorescence as a readout. Fifty-eight compounds were identified to significantly inhibit fluorescent readings of MAH. In subsequent assays, it was found that treatment of MAH-infected THP-1 macrophages with 27 of 58 hit compounds led to a significant reduction in intracellular viable bacteria, while 19 compounds decreased M. abscessus subsp. abscessus (Mab) survival rates within phagocytic cells. In addition, the hit compounds were tested in M. tuberculosis H37Ra (Mtb) and 14 compounds were found to exhibit activity in activated THP-1 cells. While the majority of compounds displayed inhibitory activity against both replicating (extracellular) and non-replicating (intracellular) forms of bacteria, a set of compounds appeared to be effective exclusively against intracellular bacteria. The efficacy of these compounds was examined in combination with current antibiotics and survival of both NTM and Mtb were evaluated within phagocytic cells. In time-kill dynamic studies, it was found that co-treatment promoted increased bacterial clearance when compared with the antibiotic or compound group alone. This study describes promising anti-NTM and anti-Mtb compounds with potential novel mechanisms of action that target intracellular bacteria in activated macrophages. 相似文献
46.
Elizaveta N. Fisher Evgeny S. Melnikov Vladimir Gegeckori Natalya V. Potoldykova Dmitry V. Enikeev Kirill A. Pavlenko Snezana Agatonovic-Kustrin David W. Morton Galina V. Ramenskaya 《Molecules (Basel, Switzerland)》2022,27(22)
A novel HPLC-ESI-MS/MS method for simultaneous gonadotropin-releasing hormone (GnRH) analogs and somatostatin analog quantitation was developed and validated. The developed method was successfully applied to pharmacokinetic studies. The sample preparation process included solid-phase extraction (SPE). Effective chromatographic separation of the analytes and internal standard (dalargin) was achieved with a C18 column, using a gradient elution with two mobile phases: 0.1% v/v formic acid (aqueous solution) and 0.1% v/v formic acid (acetonitrile solution). The linearity of the method was demonstrated within a concentration range of 0.5–20 ng/mL, with correlation coefficients between 0.998–0.999 for goserelin, buserelin, triptorelin, and octreotide, respectively. The relative standard deviation (RSD, %) values for method accuracy and precision did not exceed 20% at the lower level of quantitation (LLOQ) or 15% at other concentration levels. 相似文献
47.
Cover Picture: High‐Resolution 3D Proton MRI of Hyperpolarized Gas Enabled by Parahydrogen and Rh/TiO2 Heterogeneous Catalyst (Chem. Eur. J. 37/2014) 下载免费PDF全文
Dr. Kirill V. Kovtunov Danila A. Barskiy Aaron M. Coffey Dr. Milton L. Truong Oleg G. Salnikov Alexander K. Khudorozhkov Elizaveta A. Inozemtseva Dr. Igor P. Prosvirin Prof. Valery I. Bukhtiyarov Dr. Kevin W. Waddell Dr. Eduard Y. Chekmenev Prof. Igor V. Koptyug 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(37):11593-11593
48.
Two different methods for enumerating k-isohedral tilings are discussed. One is geometric: by splitting and gluing tiles. The other is combinatorial: by enumerating the appropriate Delaney—Dress symbols. Both methods yield 1270 types of proper 2-isohedral tilings of the plane. 相似文献
49.
Kossoy E Iron MA Rybtchinski B Ben-David Y Shimon LJ Konstantinovski L Martin JM Milstein D 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(8):2319-2326
The novel pi-accepting, pincer-type ligand, dipyrrolylphoshinoxylene (DPyPX), is introduced. This ligand has the strongest pi-accepting phosphines used so far in the PCP family of ligands and this results in some unusual coordination chemistry. The rhodium(I) complex, [(DPyPX)Rh(CO)(PR3)] (4, R=Ph, Et, pyrrolyl) is prepared by treating the relevant [(DPyPX)Rh(PR3)] (3) complex with CO and is remarkably resistant to loss of either ligand. X-ray crystallographic analysis of complex 4 b (R=Et) reveals an unusual cisoid coordination of the PCP phosphine ligands. These observations are supported by density functional theory (DFT) calculations. 相似文献
50.
Olga V. Lukashevich Natalia A. Cherepanova Renata Z. Jurkovska Albert Jeltsch Elizaveta S. Gromova 《BMC biochemistry》2016,17(1):7