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51.
Yulia Frank David Banks Marat Avakian Dmitry Antsiferov Petr Kadychagov Olga Karnachuk 《Geomicrobiology journal》2016,33(5):387-400
The dominant microbial components of fluids from wells in pristine and water-injected, high-temperature, Western Siberian oil fields, were analyzed by PCR-DGGE. Particular emphasis was placed on sulphate-reducing organisms, due to their ecological and industrial importance. Bacterial phylotypes obtained from the non-water-injected Stolbovoye oil field were more diverse than those from the Samotlor field, which is subject to secondary oil recovery by reinjection of recycled production water. The majority of phylotypes from both sites were related to Firmicutes. The low similarity to their closest relatives indicates unique bacterial communities in deep underground production waters and crude oil. Archaeal phylotypes detected only in the Samotlor samples were represented by Methanosarcinales and Methanobacteriales. 相似文献
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Julia I. Deitz Pran K. Paul Rouin Farshchi Dmitry Poplavskyy Jeff Bailey Aaron R. Arehart David W. McComb Tyler J. Grassman 《Liver Transplantation》2019,9(35)
A new experimental framework for the characterization of defects in semiconductors is demonstrated. Through the direct, energy‐resolved correlation of three analytical techniques spanning six orders of magnitude in spatial resolution, a critical mid‐bandgap electronic trap level (EV + 0.56 eV) within Ag0.2Cu0.8In1?xGaxSe2 is traced to its nanoscale physical location and chemical source. This is achieved through a stepwise, site‐specific correlated characterization workflow consisting of device‐scale (≈1 mm2) deep level transient spectroscopy (DLTS) to survey the traps present, scanning probe–based DLTS (scanning‐DLTS) for mesoscale‐resolved (hundreds of nanometers) mapping of the target trap state's spatial distribution, and scanning transmission electron microscope based electron energy‐loss spectroscopy (STEM‐EELS) and X‐ray energy‐dispersive spectroscopy for nanoscale energy‐, structure, and chemical‐resolved investigation of the defect source. This first demonstration of the direct observation of sub‐bandgap defect levels via STEM‐EELS, combined with the DLTS methods, provides strong evidence that the long‐suspected CuIn/Ga substitutional defects are indeed the most likely source of the EV + 0.56 eV trap state and serves as a key example of this approach for the fundamental identification of defects within semiconductors, in general. 相似文献
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Alexey E. Machulkin Dmitry A. Skvortsov Yan A. Ivanenkov Anton P. Ber Mikhail V. Kavalchuk Anastasia V. Aladinskaya Anastasia A. Uspenskaya Radik R. Shafikov Ekaterina A. Plotnikova Raisa I. Yakubovskaya Ekaterina A. Nimenko Nikolay U. Zyk Elena K. Beloglazkina Nikolay V. Zyk Victor E Koteliansky Alexander G. Majouga 《Bioorganic & medicinal chemistry letters》2019,29(16):2229-2235
Prostate cancer (PC) is the second most commonly occurring cancer in men. Conventional chemotherapy has wide variety of disadvantages such as high systemic toxicity and low selectivity. Targeted drug delivery is a promising approach to decrease side effects of therapy. Prostate specific membrane antigen (PSMA) is overexpressed in prostate cancer cells while low level of expression is observed in normal cells. In this study we describe the development of Glu-urea-Lys based PSMA-targeting conjugates with paclitaxel. A series of new PSMA targeting conjugates with paclitaxel was designed and synthesized. The cytotoxicity of conjugates was evaluated against prostate (LNCaP, 22Rv1 and PC-3) and non-prostate (Hek293T, VA13, A549 and MCF-7) cell lines. The most promising conjugate 21 was examined in vivo using 22Rv1 xenograft mice model. It demonstrated good efficiency comparable with paclitaxel, while reduced toxicity. 3D molecular docking study was also performed to understand underlying mechanism of binding and further optimization of the linker substructure and conjugates structure for improving the target affinity. These conjugates may be useful for further design of novel PSMA targeting delivery systems for PC. 相似文献
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Evseeva Nina V. Tkachenko Oksana V. Denisova Alena Yu. Burygin Gennady L. Veselov Dmitry S. Matora Larisa Yu. Shchyogolev Sergei Yu. 《World journal of microbiology & biotechnology》2019,35(12):1-10
World Journal of Microbiology and Biotechnology - Derived from RNA, 5?-ribonucleotides, especially Inosine-5?-monophosphate (IMP) and guanosine-5?-monophosphate (GMP), can enhance... 相似文献
58.
Stepan A. Kremis Dmitry S. Baev Alla V. Lipeeva Elvira E. Shults Tatiana G. Tolstikova Olga I. Sinitsyna Alexey V. Kochetov Tatiana S. Frolova 《Journal of biochemical and molecular toxicology》2019,33(11)
The furocoumarin backbone is a promising platform for chemical modifications aimed at creating new pharmaceutical agents. However, the high level of biological activity of furocoumarins is associated with a number of negative effects. For example, some of the naturally occurring ones and their derivatives can show genotoxic and mutagenic properties as a result of their forming crosslinks with DNA molecules. Therefore, a particularly important area for the chemical modification of natural furocoumarins is to reduce the negative aspects of their bioactivity. By studying a group of 21 compounds—1,2,3‐triazolyl modified derivatives of furocoumarin and peucedanin—using the SOS chromotest, the Ames test, and DNA‐comet assays, we revealed modifications that can neutralize the structure's genotoxic properties. Theoretical aspects of the interaction of the compound library were studied using molecular modeling and this identified the leading role of the polyaromatic molecular core that takes part in stacking‐interactions with the pi‐systems of the nitrogenous bases of DNA. 相似文献
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Andrey Sagaidachnyi Andrey Fomin Dmitry Usanov Anatoly Skripal 《Computer methods in biomechanics and biomedical engineering》2019,22(12):1009-1019
Monitoring of skin blood flow oscillations related with mechanical activity of vessels is a very useful modality during diagnosis of peripheral hemodynamic disorders. In this study, we developed a new model and technique for real-time conversion of skin temperature into skin blood flow oscillations, and vice versa. The technique is based on the analogy between the thermal properties of the human skin and electrical properties of the special low-pass filter. Analytical and approximated impulse response functions for the low- and high-pass filters are presented. The general algorithm for the reversible conversion of temperature into blood flow is described. The proposed technique was verified using simulated or experimental data of cold stress, deep inspiratory gasp, and post-occlusive reactive hyperaemia tests. The implementation of the described technique will enable to turn a temperature sensor into a blood flow sensor. 相似文献