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Food and Nutrition Sciences 2018年第5期9卷 572-583页

作者： Magomed Dibirasulaev Georgy Belozerov leonid Arkhipov Lidia Stoyanova All-Russian Scientific Research Institute of Refrigeration Industry Branch of V.M. Gorbatov Federal Research Center for Food Systems of Russian Academy of Science Moscow Russia M. v. Lomonosov Moscow State University Moscow Russia

At present, there is no method for identifying meat frozen in a thermal state acceptable for production control. The role of free nucleotides in the processes of refrigeration and storage of meat, affecting the structural and mechanical properties of muscle tissue, the formation of taste and its biological value is known. In this article we compared methods for identifying the thermal state of meat based on the determination of the composition and content of free nucleotides by high-performance liquid chromatography (HPLC) and spectrophotometry [SF]. High-purity reference substances were used: free nucleotides—ATP, ADP, AMP, IMP and nucleosides-inosine and hypoxanthine. It has been experimentally established that the characteristic peaks of the absorption spectra for extracts of free nucleotides of meat frozen depended from thermal state of meat. The content of ATP is 21.8 times higher in meat frozen in a fresh state, and the amount of IMF is 12.3 times lower than in meat frozen after cooling. The results of studies of meat frozen using the HPLC method and the developed SF method show the adequacy of the data obtained by both methods. SF-method based on the determination of the optical density of the extracts of free nucleotides is recommended to justify the choice of technological process meat defrost modes.

关键词： Thermal State of Meat Free Nucleotides and Nucleosides HPLC and Spectrophotometric Methods Defrost Modes

Expression of casein kinase genes in glioma cell line U87: Effect of hypoxia and glucose or glutamine deprivation

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Natural Science 2012年第1期4卷 38-46页

作者： Dmytro O. Minchenko leonid L. Karbovskyi Serhii v. Danilovskyi Anastasia P. Kharkova Oleksandr H. Minchenko 不详

The endoplasmic reticulum-nuclei-1 (ERN1) sensing and signaling enzyme mediates a set of complex intracellular signaling events known as the unfolded protein response. We have studied the effect of hypoxia and ischemic conditions (glucose or glutamine deprivation) on the expression of several casein kinase-1 and -2 genes in glioma U87 cells and its subline with suppressed function of ERN1. It was shown that blockade of ERN1, the key endoplasmic reticulum stress sensor, leads to an increase in the expression levels of casein kinase-1G2, -1E, -2B and NUCKS1 mRNA, but suppresses casein kinase-1A1, -1D and -2A1. Moreover, the expression levels of casein kinase-1A1, -1D and 1G3 as well as casein kinase-2A1 and -2A2 mRNAs are significantly increased under glutamine dep- rivation conditions both in control and ERN1- deficient glioma cells. At the same time, casein kinase-1E, -2B and NUCKS1 mRNA expression levels are also increased under this condition, but only in cells with suppressed function of ERN1. The expression level of NUCKS1 mRNA, however, is decreased both in control glioma cells and in genetically modified cells, but casein kinase-1G2—only in control U87 cells. Cell exposure to glucose deprivation conditions enhances the expression levels of casein kinase- 1D, 1G3, -1E and -2A1 in both types of glioma cells used, but casein kinase-2B expression levels increase only in cells with suppressed function of ERN1. Hypoxia induces or suppresses the expression of most of the studied genes mainly in ERN1-knockdown cells only. Results of this study show that hypoxia as well as glutamine and glucose deprivation conditions change the expression level most of casein kinase genes and that these effects are dependent on ERN1 signaling enzyme function.

关键词： mRNA Expression Casein Kinase 1A 1D 1G2 1G3 1E 2A1 2A2 2B and NUCKS1 Glioma Cells Endoplasmic Reticulum-Nuclei-1 (ERN1 IRE-1α) Hypoxia Glucose and Glutamine Deprivation

The Jeans Equation Generalization for the Rotating Universe

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International Journal of Astronomy and Astrophysics 2014年第4期4卷 614-619页

作者： leonid M. Chechin Aigerim T. Ibraimova Astrophysical Institute Named After v.G. Fessenkov Almaty Kazakhstan

The generalization of Jeans equation in expanding and rotating Universe is given. We found the generalized frequency of baryonic substrate oscillations in the rotating Universe. In doing this, two cases were considered: the generalized wave vector coincides with the Jeans wave vector and second case, when the generalized wave vector tends to zero.

关键词： Jeans Equations Rotating Universe

Quantum Supercurrent Transistors in Silicon Quantum Wells Confined by Superconductor Barriers

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Journal of Modern Physics 2011年第4期2卷 256-273页

作者： Nikolay T. Bagraev Edward Yu. Danilovsky leonid E. Klyachkin Andrei A. Kudryavtsev Roman v. Kuzmin Anna M. Malyarenko Wolfgang Gehlhoff vladimir v. Romanov 不详

We present the findings of spin-dependent single-hole and pair-hole transport in plane and across the p-type high mobility silicon quantum wells (Si-QW), 2 nm, confined by the superconductor δ-barriers on the n-type Si (100) surface. The oscillations of the conductance in normal state and the zero-resistance supercurrent in superconductor state as a function of the top gate voltage are found to be correlated by on- and off-resonance tuning the two-dimensional levels of holes in Si-QW with the Fermi energy in the superconductor δ-barriers. The SIMS and STM studies have shown that the δ-barriers heavily doped with boron, 5 × 1021 cm–3, represent really alternating arrays of silicon empty and doped dots, with dimensions restricted to 2 nm. This concentration of boron seems to indicate that each doped dot located between empty dots contains two impurity atoms of boron. The EPR studies show that these boron pairs are the trigonal dipole centres, B+ - B–, that contain the pairs of holes, which result from the negative -U reconstruction of the shallow boron acceptors, 2B0 => B+ - B–. The electrical resistivity, magnetic susceptibility and specific heat measurements demonstrate that the high density of holes in the Si-QW (> 1011 cm–2) gives rise to the high temperature superconductor properties for the δ-barriers. The value of the superconductor energy gap obtained is in a good agreement with the data derived from the oscillations of the conductance in normal state and of the zero-resistance supercurrent in superconductor state as a function of the bias voltage. These oscillations appear to be correlated by on- and off-resonance tuning the two-dimensional subbands of holes with the Fermi energy in the superconductor δ-barriers. Finally, the proximity effect in the S-Si-QW-S structure is revealed by the findings of the quantization of the supercurrent and the multiple Andreev reflection (MAR) observed both across and along the Si-QW plane thereby identifying the spin transis

关键词： Silicon Quantum Well Superconductor δ-barrier ESR Dipole Boron Center Multiple Andreev Reflection Supercurrent Conductance EDESR Silicon Microcavity

Intervalley Scattering of Electrons in n-Si at T = 77 ÷450 K

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World Journal of Condensed Matter Physics 2013年第1期3卷 43-45页

作者： valerii Ermakov volodymyr Kolomoets leonid Panasyuk Baja Orasgulyev Caspian State University Aktau Kazakhtan v. Lashkaryov Institute for Semiconductor Physics NAS of Ukraine Kiev Ukraine

The change in electron mobility of n-Si with increasing the temperature which may be due to the inclusion of gLOphonon energy of 720 K, is presented. Under orientation of the uniaxial pressure X//[110]//J, g-transitions are attached in the directions [100] and [010]. The f-transitions are not completely removed from valleys located in the plane (100). In this case, there is no change in the slope of the dependence logρ vs. logT for the temperature range 77 to 450 K. So, no appreciable contribution of g-transitions to intervalley scattering occurs, while the observed is the decisive role of f-transitions to intervalley scattering. The results of measuring of the tensoresistivity effect for n-Si crystals under X//[001]//J are presented at these temperatures too.

关键词： Silicon f-Transitions g-Transitions Tensoresistivity Effect Uniaxial Strain

EDESR and ODMR of Impurity Centers in Nanostructures Inserted in Silicon Microcavities

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Journal of Modern Physics 2011年第6期2卷 544-558页

作者： Nikolay T Bagraev vladimir A. Mashkov Edward Yu Danilovsky Wolfgang Gehlhoff Dmitrii S. Gets leonid E Klyachkin Andrei A Kudryavtsev Roman v. Kuzmin Anna M Malyarenko vladimir v Romanov 不详

We present the first findings of the new electrically- and optically-detected magnetic resonance technique [ED electron spin resonance (EDESR) and (ODMR)] which reveal single point defects in the ultra-narrow silicon quantum wells (Si-QW) confined by the superconductor δ-barriers. This technique allows the ESR identification without the application of the external cavity as well as a high frequency source and recorder, with measuring the only magnetoresistance (EDESR) and transmission (ODMR) spectra within frameworks of the excitonic normal-mode coupling (NMC) caused by the microcavities embedded in the Si-QW plane. The new resonant positive magnetoresistance data are interpreted here in terms of the interference transition in the diffusive transport of free holes respectively between the weak antilocalization regime in the region far from the ESR of a paramagnetic point defect located inside or near the conductive channel and the weak localization regime in the nearest region of the ESR of that defect.

关键词： Silicon Microcavity Quantum Well ESR Bound Exciton Trigonal Centers Single Centers Carbon ODMR

Essential Oils from Different Parts of the Sea Buckthorn <i>Hippophae rhamnoides</i>L.

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Advances in Bioscience and Biotechnology 2019年第8期10卷 233-243页

作者： Nikolay M. Slynko leonid v. Kuibida Ludmila E. Tatarova George U. Galitsyn Tatiana N. Goryachkovskaya Sergey E. Peltek The Federal Research Center Institute of Cytology and Genetics SB RAS Novosibirsk Russia Institute of Chemical Kinetics and Combustion SB RAS Novosibirsk Russia

The study investigated essential oils of berries and green biomass of the sea buckthorn at various growth stages. Plant material of H. rhamnoídes ssp. mongolica was collected in the experimental fields of the Institute of Cytology and Genetics SB RAS (Siberia, Russia). volatile compounds and essential oils were detected. Green spring shoots without leaves, first-year seedlings without leaves and berries were analyzed. In all studied exemplars, 103 volatile compounds were defined among which considerable proportion wasn’t found in a sea-buckthorn earlier. Phenylpropanoids prevailed in essential oils composition from seedlings. Alkanes and phenylpropanoids prevailed in shoots. Berries contained mostly carboxylic acids and their esters. These data can be applied to a fingerprint of various cultivars of a sea-buckthorn with relevance to food science and technology.

关键词： Hippophae rhamnoídes Essential Oils volatile Compounds Gas Chromatography-Mass Spectrometry (GC-MS) Analysis Chemotaxonomy

C60 fullerene enhances cisplatin anticancer activity and overcomes tumor cell drug resistance

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Nano Research 2017年第2期10卷 652-671页

作者： Svitlana Prylutska Rostyslav Panchuk Grzegorz Golunski Larysa Skivka Yuriy Prylutskyy vasyl Hurmach Nadya Skorohyd Agnieszka Borowik Anna Woziwodzka Jacek Piosik Olena Kyzyma vasil Garamus leonid Bulavin Maxim Evstigneev Anatoly Buchelnikov Rostyslav Stoika Walter Berger Uwe Ritter Peter Scharff Taras Shevchenko National University of Kyiv 64 Volodymyrska Str. 01601 Kyiv Ukraine Institute of Cell Biology NAS of Ukraine 14-16 Drahomanov 5tr. 79005 Lviv Ukraine Laboratory of Biophysics Intercollegiate Faculty ofBiotechnology UG-MUG Abrahama 58 80-307 Gdansk Poland Joint Institute for Nuclear Research 6 Joliot-Curie Str. 141980 Dubna Moscow reg. Russia Helmholtz-Zentrum Geesthacht: Centre for Materials and Coastal Research 1 Max-Planck Str. 21502 Geesthacht Germany Belgorod State University 85 Pobedy Str. 308015 Belgorod Russia Institute of Cancer Research and Comprehensive Cancer Center Medical University Vienna 1090 8A Borschkegasse Vienna Austria Institute of Chemistry and Biotechnology Technical University ofllmenau 25 Weimarer Str. 98693 Ilmenau Germany

We formulated and analyzed a novel nanoformulation of the anticancer drug cisplatin （Cis） with C60 fullerene （C60＋Cis complex） and showed its higher toxicity toward tumor cell lines in vitro when compared to Cis alone. The highest toxicity of the complex was observed in HL-60/adr and HL-60/vinc chemotherapy- resistant human leukemia cell sublines （resistant to Adriamycin and vinculin, respectively）. We discovered that the action of the C60＋Cis complex is associated with overcoming the drug resistance of the tumor cell lines through observing an increased number of apoptotic cells in the Annexin v/PI assay. Moreover, in vivo assays with Lewis lung carcinoma （LLC） C57BL/6J male mice showed that the C60＋Cis complex increases tumor growth inhibition, when compared to Cis or C60 fullerenes alone. Simultaneously, we conducted a molecular docking study and performed an Ames test. Molecular docking specifies the capability of a C60 fullerene to form van der Waals interactions with potential binding sites on P-glycoprotein （P-gp）, multidrug resistance protein 1 （MRP-1）, and multidrug resistance protein 2 （MRP-2） molecules. The observed phenomenon revealed a possible mechanism to bypass tumor cell drug resistance by the C60＋Cis complex. Additionally, the results of the Ames test show that the formation of such a complex diminishes the Cis mutagenic activity and may reduce the probability of secondary neoplasm formation. In conclusion, the C60＋Cis complex effectively induced tumor cell death in vitro and inhibited tumor growth in vivo, overcoming drug resistance likely by the potential of the C60 fullerene to interact with P-gp, MRP-1, and MRP-2 molecules. Thus, the C60＋Cis complex might be a potential novel chemotherapy modification.

关键词： molecular docking,small-angle X-ray scattering,apoptosis,mutagenic activity lung carcinoma (LLC),cytotoxicity

One-Pot Process of Naphthoquinones Synthesis from Hydroquinone in the Presence of Solutions of Mo-v-P Heteropolyacids as Bifunctional Catalysts

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Modern Research in Catalysis 2019年第1期8卷 1-9页

作者： leonid L. Gogin Elena G. Zhizhina Zinaida P. Pai Federal Research Center Boreskov Institute of Catalysis Novosibirsk Russia

1,4-Naphthoquinones (NQ) is a class of organic compounds with a number of important properties. However, the existing methods of their synthesis either give a low NQ yield or multistage and require a lot of time. In the present work new one-pot process of NQ synthesis from hydroquinone (HQ) and substituted 1,3-dienes at room temperature is proposed. The solution of heteropolyacid H7PMo8v4O40 (HPA-4) is used as a bifunctional (acid and redox) catalyst for this process. The influence of a number of factors on key process parameters has been studied. It is demonstrated that unsubstituted and a number of alkyl substituted NQ with the yields of 50% - 80% and purity of 92% - 99% can be obtained by this method. The results obtained allow to significantly simplify the synthesis of NQ directly from HQ in comparison with the described similar methods.

关键词： Hydroquinone Naphthoquinones Heteropolyacid Diene Synthesis

Spherically Symmetric Problem of General Relativity for an Elastic Solid Sphere

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