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1.
Russ J Bioorg Chem ; 49(1): 41-51, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37192981

RESUMO

Some new polycationic amphiphiles containing a disulfide group were synthesized. Cationic liposomes formed from the compounds synthesized and a helper lipid 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine were not toxic for HEK293 and HeLa cells and were highly effective when delivering a fluorescently labeled oligodeoxyribonucleotide. The efficacy of plasmid DNA delivery depended on the cell line and the amphiphile structure, liposomes based on tetracationic amphiphiles being the most effective transfectants. These liposomes can be used for in vitro transfection of eukaryotic cells as well as for further in vivo biological studies.

2.
Khirurgiia (Mosk) ; (10): 117-123, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37916565

RESUMO

The review is devoted to mostly international data on patient safety during surgical procedures. The author emphasizes surgical safety checklist for surgical interventions as a tool developed by the WHO team. The principal objective of this document is protection of patients from harm following unintended misses and casual circumstances. The author tried to explain the basic principles and ideas underlying the checklist procedure. An importance of understanding the process by administration and surgical team is emphasized because its absence deprives this non-complicated and helpful procedure of necessary sense. The problems of patient safety in hospitals of the Russian Federation are also discussed.


Assuntos
Lista de Checagem , Procedimentos Cirúrgicos Operatórios , Humanos , Lista de Checagem/métodos , Hospitais , Segurança do Paciente , Federação Russa , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Organização Mundial da Saúde
3.
Nanotechnology ; 29(36): 365304, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-29897890

RESUMO

Tuning the band structure and, in particular, gap opening in 1D and 2D materials through their deformation is a promising approach for their application in modern semiconductor devices. However, there is an essential breach between existing laboratory scale methods applied for deformation of low-dimensional materials and the needs of large-scale production. In this work, we propose a novel method which is potentially well compatible with high end technological applications: single-walled carbon nanotubes (SWCNTs) first deposited on the flat surface of a supporting wafer, which has been pre-implanted with H+ and He+ ions, are deformed in a controlled and repetitive manner over blisters formed after subsequent thermal annealing. By using resonant Raman spectroscopy, we demonstrate that the SWCNTs clamped by metallic stripes at their ends are deformed over blisters to an average tensile strain of 0.15 ± 0.03%, which is found to be in a good agreement with the value calculated taking into account blister's dimensions. The principle of the technique may be applied to other 1D and 2D materials in perspective.

4.
Mol Biol (Mosk) ; 51(1): 118-125, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28251974

RESUMO

The efficiency of the antitumor immune response triggered by dendritic cell (DC)-based vaccines depends predominantly on the efficiency of delivering tumor antigen-coding nucleic acids into DCs. Mannosylated liposomes were used to deliver tumor total RNA into DCs both ex vivo and in vivo, and the cytotoxic T-lymphocyte (CTL) antitumor response was assayed. The liposomes contained the mannosylated lipid conjugate 3-[6-(α-D-mannopyranosyloxy)hexyl]amino-4-{6-[rac-2,3-di(tetradecyloxy)prop-1-yl oxycarbonylamino]hexyl}aminocyclobut-3-en-1,2-dione), the polycationic lipid 2X3 (1,26-bis(cholest-5-en-3ß-yloxycarbonylamino)-7,11,16,20-tetraazahexacosane tetrahydrochloride), and the zwitterionic lipid DOPE (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine) at a molar ratio of 1: 3: 6 and were used as a transfection agent. Total RNA isolated from B16-F10 mouse melanoma cells served as a source of tumor antigens. Systemic administration of mannosylated liposomes-tumor RNA complexes into circulation of melanoma-bearing mice induced an efficient CTL response, which reduced the melanoma cell index in vitro with the same efficiency (by a factor of 2.8) as CTLs activated via an inoculation of DCs loaded with complexes of the same composition ex vivo. Complexes of tumor RNA with control liposomes, which lacked the mannosylated lipid conjugate, or DCs transfected with these complexes ex vivo were less efficient and reduced the melanoma cell count by a factor of only 1.6-1.8.


Assuntos
Antígenos de Neoplasias/administração & dosagem , Vacinas Anticâncer , Lipossomos , RNA Neoplásico/administração & dosagem , Linfócitos T Citotóxicos/imunologia , Animais , Células Dendríticas , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Transfecção
5.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39037299

RESUMO

This work presents a system upgrade of the High Resolution Thomson Scattering (HRTS) diagnostic [Pasqualotto et al., Rev. Sci. Instrum. 75, 3891-3893 (2004)] on JET that allows it to measure low temperature (1-500 eV) plasma pre- and post-Thermal quench (TQ), which would help us further understand the Shattered Pellet Injection (SPI) physics. The upgrade was done by connecting optic fibers from the original HRTS system to four spectrometers specialized in measuring low temperature plasmas. The upgraded system allows for the measurement of low temperature plasma at up to 12 spatial points, which can be flexibly distributed throughout the JET outer midplane profile during the dedicated SPI experiments. In other JET experiments, four previously unused groups of fibers were used to measure the central plasma to provide disruption data without changing the standard HRTS system. The low temperature Thomson scattering system was installed, commissioned, and cross-calibrated against the standard HRTS diagnostic in a calibration pulse. The system worked reliably during the JET experiments and provided electron density and temperature profiles for pre- and post-TQ low temperature plasmas in the SPI campaign.

6.
Rev Sci Instrum ; 94(1): 013506, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725564

RESUMO

Thomson scattered light is polarized in the same orientation as the incident laser beam at low electron temperatures (Te). At high Te, part of the spectrum begins to become randomly polarized due to relativistic reasons. First measurements of the depolarized Thomson scattering spectrum were obtained from Joint European Torus (JET) pulses in 2016. This paper builds upon these initial measurements with the data obtained during 2021. These new measurements improve upon first results, in particular, by obtaining spectral measurements of the depolarized spectrum. The recent JET campaign was well suited to these measurements with long and hot plasmas. The resulting data are averaged over many plasmas and laser pulses to obtain a measurement of the amount of "p" and "s" scattered light as a function of Te. This experimentally obtained d(p/s)/dTe is then fitted and found to show reasonable agreement with the theoretically predicted depolarized fraction. Error estimates on the measured "p/s" have been obtained and show that the measurements are meaningful. This is good news for ITER for which the intention is to use this measurement as a check on Te determined by the core plasma Thomson scattering diagnostic by using conventional spectral measurement techniques.

7.
J Phys Chem B ; 127(5): 1197-1208, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36696698

RESUMO

The paper presents the results, which are consistent within 2%, obtained both in the simulation of molecular dynamics and in the experiment on the study of the kinetic properties of molten FLiNaK with addition of lanthanide fluorides. The parameters of the Born-Huggins-Meier potential for the interaction of CeF3 or NdF3 with FLiNaK components are first calculated using the ab initio approach. The enthalpy of the system with dissolved CeF3 or NdF3 calculated in the model increases by ∼4.4% over the entire temperature range studied (800 ≤ T ≤ 1020 K). The self-diffusion coefficients of the molten salt components are calculated from the Einstein relation and also estimated from the shear viscosity data. The temperature dependences of the shear viscosity of molten FLiNaK as well as FLiNaK with additions of 15 mol % CeF3 or NdF3 are determined experimentally and by calculation. In addition, the dependence of shear viscosity on the concentration of CeF3 and NdF3 in FLiNaK is measured and calculated. The linear growth of the shear viscosity with the CeF3 and NdF3 concentrations is obtained. Experimental dependence is in good agreement with the simulated results in the case of NdF3, and there is the discrepancy while CeF3 addition. An analytical approximation of the temperature and concentration dependences for the viscosity of molten FliNaK and for the calculated self-diffusion coefficients of constituent elements is proposed. Linear approximation of temperature dependence of the self-diffusion coefficients of similar components in the corresponding extended systems is presented.

8.
Zh Evol Biokhim Fiziol ; 48(6): 548-56, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23401964

RESUMO

Comparative study has been carried of effect of the three-day long starvation, running, and their combination on morphological parameters of rat blood, lipid metabolism, and activity of blood Na,K-ATPase. Different effect has been shown of these stress factors on the blood erythrocyte composition. Starvation is accompanied by the most pronounced release of stored erythrocyte into blood, which results in a significant decrease both of the total amount of reticulocytes and the complete absence of reticulocytes of the I stage of maturity (the youngest). The running on treadmill led to a significant increase of the total amount of blood reticulocytes and to multiple increase of immature reticulocytes (RC-I and RC-II), which can indicate some stress of the bone marrow erythroid stem line. The curve of acid resistance of blood reticulocytes has shown the animal to experience the greatest stress at a combination of starvation and running. Starvation and running produced different effects on blood lipid characteristics. The content of triacylglycerides (TAG) in blood rose by 40% at starvation and decreased by 30% at running, a similar tendency being found for index of atherogeneity. The fatty acid composition of blood phospholipids at running and its combination with starvation practically did not differ from control. A change of Na,K-ATPase, which is so characteristic of reaction to various kinds of stress, sharply fell at starvation (by 22%), but increased at running (by 13%) and decreased markedly at combination of these actions. Absorption spectra of lipid extracts of the whole blood of the rats submitted to various stress actions showed that extracted from blood (at different amount depending on the kind of action) is an organic substance with coupled bonds, which absorbs light in the diapason of 360-620 nm. The absorption of light in the diapason of 400-410 nm has been found to belong to the Soret band of ferroheme and ferriheme. The shift of the Soret band indicates electron transitions in the iron cation. By the change and disappearance of the Soret band, it is possible to judge about the processes occurring in the lipid extract. The disappearance of the Soret band in the lipid extract indicates formation in it of steady radicals as a result of the ferriheme disintegration due to accumulation of energy in porphyrin, which does not seem to occur in the blood cell membranes. The iron atom in the ferriheme molecule is known to accept electron and yields a part of energy probably to porphyrin. Then ferriheme yields electron and becomes ferriheme with excess of energy in porphyrin. Hence, at admission of the next electron to the iron atom the porphyrin molecule is to get rid of the energy obtained earlier to prevent its disintegration. The heme is possible to be an accumulator and distributor of energy in tissue.


Assuntos
Heme , Ferro , Lipídeos/sangue , Reticulócitos , Animais , Ácidos Graxos/sangue , Heme/análise , Heme/metabolismo , Hemina/metabolismo , Ferro/análise , Ferro/metabolismo , Luz , Masculino , Fosfolipídeos/sangue , Condicionamento Físico Animal , Porfirinas/sangue , Ratos , Contagem de Reticulócitos , Reticulócitos/citologia , Reticulócitos/metabolismo , ATPase Trocadora de Sódio-Potássio/sangue , Inanição/sangue , Inanição/metabolismo
9.
Rev Sci Instrum ; 93(9): 093515, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182493

RESUMO

The Joint European Torus (JET) is the only tokamak in the world able to operate in Deuterium-Tritium (DT) plasmas. A successful DT experimental campaign, the DTE2, has recently been carried out, providing unique opportunities for studying both physics and technological aspects. In particular, it allowed us to investigate and benchmark the solutions adopted to attenuate the significant 14 MeV neutron flux, needed to enable high-resolution gamma-ray spectroscopy measurements on a tokamak. While in inertial confinement experiments, gamma-rays and neutrons are discriminated through time-of-flight techniques; in magnetic confinement experiments, the neutron attenuators are a key element to allow gamma-ray measurements in order to reestablish the 1 × 105 to 1 background to signal ratio. In this paper, the role of the reference neutron attenuators at JET, based on LiH, has been analyzed and described.

10.
Rev Sci Instrum ; 93(9): 093525, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182521

RESUMO

The most performant deuterium-tritium (DT) plasma discharges realized by the Joint European Torus (JET) tokamak in the recent DT campaign have produced neutron yields on the order of 1018 n/s. At such high neutron yields, gamma-ray spectroscopy measurements with scintillators are challenging as events from the neutron-induced background often dominate over the signal, leading to a significant fraction of pileup events and instability of the photodetector gain along with the consequent degradation of the reconstructed spectrum. Here, we describe the solutions adopted for the tangential lanthanum bromide spectrometer installed at JET. A data acquisition system with free streaming mode digitization capabilities for the entire duration of the discharge has been used to solve dead-time related issues and a data reconstruction code with pileup recovery and photodetector gain drift restoration has been implemented for off-line analysis of the data. This work focuses on the acquired data storage and parsing, with a detailed explanation of the pileup recovery and gain drift restoration algorithms.

11.
Rev Sci Instrum ; 93(9): 093520, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182523

RESUMO

A new deuterium-tritium experimental, DTE2, campaign has been conducted at the Joint European Torus (JET) between August 2021 and late December 2021. Motivated by significant enhancements in the past decade at JET, such as the ITER-like wall and enhanced auxiliary heating power, the campaign achieved a new fusion energy world record and performed a broad range of fundamental experiments to inform ITER physics scenarios and operations. New capabilities in the area of fusion product measurements by nuclear diagnostics were available as a result of a decade long enhancement program. These have been tested for the first time in DTE2 and a concise overview is provided here. Confined alpha particle measurements by gamma-ray spectroscopy were successfully demonstrated, albeit with limitations at neutron rates higher than some 1017 n/s. High resolution neutron spectroscopy measurements with the magnetic proton recoil instrument were complemented by novel data from a set of synthetic diamond detectors, which enabled studies of the supra-thermal contributions to the neutron emission. In the area of escaping fast ion diagnostics, a lost fast ion detector and a set of Faraday cups made it possible to determine information on the velocity space and poloidal distribution of the lost alpha particles for the first time. This extensive set of data provides unique information for fundamental physics studies and validation of the numerical models, which are key to inform the physics and scenarios of ITER.

12.
Rev Sci Instrum ; 93(11): 113512, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461481

RESUMO

Dedicated nuclear diagnostics have been designed, developed, and built within EUROFUSION enhancement programs in the last ten years for installation at the Joint European Torus and capable of operation in high power Deuterium-Tritium (DT) plasmas. The recent DT Experiment campaign, called DTE2, has been successfully carried out in the second half of 2021 and provides a unique opportunity to evaluate the performance of the new nuclear diagnostics and for an understanding of their behavior in the record high 14 MeV neutron yields (up to 4.7 × 1018 n/s) and total number of neutrons (up to 2 × 1019 n) achieved on a tokamak. In this work, we will focus on the 14 MeV high resolution neutron spectrometers based on artificial diamonds which, for the first time, have extensively been used to measure 14 MeV DT neutron spectra with unprecedented energy resolution (Full Width at Half Maximum of ≈1% at 14 MeV). The work will describe their long-term stability and operation over the DTE2 campaign as well as their performance as neutron spectrometers in terms of achieved energy resolution and high rate capability. This important experience will be used to outline the concept of a spectroscopic neutron camera for the SPARC tokamak. The proposed neutron camera will be the first one to feature the dual capability to measure (i) the 2.5 and 14 MeV neutron emissivity profile via the conventional neutron detectors based on liquid or plastics scintillators and (ii) the 14 MeV neutron spectral emission via the use of high-resolution diamond-based spectrometers. The new opportunities opened by the spectroscopic neutron camera to measure plasma parameters will be discussed.

13.
Bioorg Med Chem Lett ; 21(10): 2937-40, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21463941

RESUMO

In this study, we synthesized a new galactosylated cationic lipid and investigated its biological activity. The structure of lipid combines both spermine residue for DNA compaction and galactose moiety for the improvement of aggregation behavior of lipoplexes. Lipid was low toxic for different mammalian cells, and was able both to compact plasmid DNA and to mediate cellular accumulation of various nucleic acids (ODN, pDNA and siRNA) exhibiting biological activity (transgene expression, gene silencing).


Assuntos
Galactose/química , Lipídeos/síntese química , Poliaminas/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Citometria de Fluxo , Técnicas de Transferência de Genes , Humanos , Lipídeos/química , Lipídeos/toxicidade , Lipossomos/química , Microscopia de Força Atômica , Estrutura Molecular , Polieletrólitos , Transfecção
14.
Bioorg Khim ; 37(4): 567-76, 2011.
Artigo em Russo | MEDLINE | ID: mdl-22097000

RESUMO

Amino analogues of cholic acid were synthesized by reduction of oximes with combination of titanium(III) chloride and sodium cyanoborohydride.


Assuntos
Aminas/síntese química , Colatos/síntese química , Aminas/química , Boroidretos/química , Colatos/química , Hidróxidos/química , Oximas/química , Titânio/química
15.
Am J Physiol Heart Circ Physiol ; 299(2): H332-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20495142

RESUMO

Adriamycin (ADR) is an established, life-saving antineoplastic agent, the use of which is often limited by cardiotoxicity. ADR-induced cardiomyopathy is often accompanied by depressed myocardial high-energy phosphate (HEP) metabolism. Impaired HEP metabolism has been suggested as a potential mechanism of ADR cardiomyopathy, in which case the bioenergetic decline should precede left ventricular (LV) dysfunction. We tested the hypothesis that murine cardiac energetics decrease before LV dysfunction following ADR (5 mg/kg ip, weekly, 5 injections) in the mouse. As a result, the mean myocardial phosphocreatine-to-ATP ratio (PCr/ATP) by spatially localized (31)P magnetic resonance spectroscopy decreased at 6 wk after first ADR injection (1.79 + or - 0.18 vs. 1.39 + or - 0.30, means + or - SD, control vs. ADR, respectively, P < 0.05) when indices of systolic and diastolic function by magnetic resonance imaging were unchanged from control values. At 8 wk, lower PCr/ATP was accompanied by a reduction in ejection fraction (67.3 + or - 3.9 vs. 55.9 + or - 4.2%, control vs. ADR, respectively, P < 0.002) and peak filling rate (0.56 + or - 0.12 vs. 0.30 + or - 0.13 microl/ms, control vs. ADR, respectively, P < 0.01). PCr/ATP correlated with peak filling rate and ejection fraction, suggesting a relationship between cardiac energetics and both LV systolic and diastolic dysfunction. In conclusion, myocardial in vivo HEP metabolism is impaired following ADR administration, occurring before systolic or diastolic abnormalities and in proportion to the extent of eventual contractile abnormalities. These observations are consistent with the hypothesis that impaired HEP metabolism contributes to ADR-induced myocardial dysfunction.


Assuntos
Trifosfato de Adenosina/metabolismo , Antibióticos Antineoplásicos , Doxorrubicina , Metabolismo Energético , Miocárdio/metabolismo , Fosfocreatina/metabolismo , Disfunção Ventricular Esquerda/metabolismo , Função Ventricular Esquerda , Animais , Modelos Animais de Doenças , Regulação para Baixo , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Contração Miocárdica , Volume Sistólico , Fatores de Tempo , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/fisiopatologia
16.
Bioorg Khim ; 36(5): 714-20, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21063458

RESUMO

An approach to synthesis of cationic carbohydrate surfactants with potential antimicrobial or transfected activities is described.


Assuntos
Galactose/química , Tensoativos/síntese química , Cátions , Estrutura Molecular , Solventes , Tensoativos/química
17.
Angiol Sosud Khir ; 16(2): 120-5, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21032880

RESUMO

Based on studying venous trunks and their syntopia, previously performed on a total of 160 cadavers we elaborated" methods of "cross" shunting. Clinical application thereof in ten patients presenting with severe arterial hypertension accompanied by type 2 diabetes mellitus made it possible to decrease both mortality and complication rates.


Assuntos
Aterosclerose/cirurgia , Diabetes Mellitus Tipo 2/complicações , Hipertensão/cirurgia , Veia Porta/cirurgia , Veia Cava Inferior/cirurgia , Adulto , Idoso , Aldosterona/sangue , Aterosclerose/sangue , Aterosclerose/complicações , Cadáver , Diabetes Mellitus Tipo 2/sangue , Feminino , Seguimentos , Humanos , Hipertensão/sangue , Hipertensão/complicações , Hipertensão/mortalidade , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Seleção de Pacientes , Reologia , Fatores de Tempo
18.
J Phys Chem Lett ; 11(14): 5668-5673, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32586094

RESUMO

In this Letter, we study the structural, electronic, and elastic properties of single-layer striped borophene stacked on top of single-layer graphene. Through DFT calculation, we show that both the properties of striped borophene and graphene are not fully preserved in the novel heterostructure, which obviously depends on the nature of the chemical bond between the layers. The obtained phonon spectrum confirms the stability of this compound. The divergence of branches in the band structure appears below the Fermi level in the K point in the first Brillouin zone. Moreover, this heterostructure possesses excellent elastic properties and can be considered for use in the field of 2D acousto- and optoelectronics.

19.
J Chem Theory Comput ; 16(4): 2065-2070, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32150411

RESUMO

We present the molecular hyperdynamics algorithm and its implementation to the nonorthogonal tight-binding model NTBM and the corresponding software. Due to its multiscale structure, the proposed approach provides the long time scale simulations (more than 1 s), unavailable for conventional molecular dynamics. No preliminary information about the system's potential landscape is needed for the use of this technique. The optimal interatomic potential modification is automatically derived from the previous simulation steps. The average time between adjusted potential energy fluctuations provides an accurate evaluation of physical time during the hyperdynamics simulation. The main application of the presented hyperdynamics method is the study of thermal-induced defects arising in the middle-sized or relatively large atomic systems at low temperatures. To validate the presented method, we apply it to the C60 cage and its derivative C60NH2. Hyperdynamics leads to the same results as a conventional molecular dynamics, but the former possesses much higher performance and accuracy due to the wider temperature region. The coefficient of acceleration achieves 107 and more.

20.
Bioorg Khim ; 35(5): 696-700, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19915649

RESUMO

The synthesis of cationic lipids on the basis of 1,2-di-O-tetradecylglycerol is described. The cationic groups represented by the residues of nitrogen-containing heterocyclic bases are attached to the diglyceride backbone through O,O- and N,O-acetal bonds. The resulting lipids can be used as nonviral gene delivery systems to eukaryotic cells.


Assuntos
Diglicerídeos/química , Diglicerídeos/síntese química , Transfecção , Cátions
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