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141.
142.
Kseniya A. Mariewskaya Anton P. Tyurin Alexey A. Chistov Vladimir A. Korshun Vera A. Alferova Alexey V. Ustinov 《Molecules (Basel, Switzerland)》2021,26(13)
Antiviral action of various photosensitizers is already summarized in several comprehensive reviews, and various mechanisms have been proposed for it. However, a critical consideration of the matter of the area is complicated, since the exact mechanisms are very difficult to explore and clarify, and most publications are of an empirical and “phenomenological” nature, reporting a dependence of the antiviral action on illumination, or a correlation of activity with the photophysical properties of the substances. Of particular interest is substance-assisted photogeneration of highly reactive singlet oxygen (1O2). The damaging action of 1O2 on the lipids of the viral envelope can probably lead to a loss of the ability of the lipid bilayer of enveloped viruses to fuse with the lipid membrane of the host cell. Thus, lipid bilayer-affine 1O2 photosensitizers have prospects as broad-spectrum antivirals against enveloped viruses. In this short review, we want to point out the main types of antiviral photosensitizers with potential affinity to the lipid bilayer and summarize the data on new compounds over the past three years. Further understanding of the data in the field will spur a targeted search for substances with antiviral activity against enveloped viruses among photosensitizers able to bind to the lipid membranes. 相似文献
143.
采用磁控溅射和金属剥离工艺制备了结构为p-Si/HfO2/Ti和p-Si/HfO2/Al2O3/Ti的阻变存储器。两器件均表现出双极性电阻转变特性。插入的Al2O3层使得高阻态导电机制从空间电荷限制电流导电向肖特基发射控制导电转变,器件高低阻态阻值比从~61倍提高到了惊人的2.15×10^8倍。通过限制set电流的方式实现了多值存储,器件的四个阻态都能够非常稳定地在85 ℃高温下保持10^4 s,有利于多值存储的实际应用。 相似文献
144.
Maki Komiya Miki Kato Daisuke Tadaki Teng Ma Hideaki Yamamoto Ryugo Tero Yuzuru Tozawa Michio Niwano Ayumi Hirano‐Iwata 《Chemical record (New York, N.Y.)》2020,20(7):730-742
An artificial cell membrane that is composed of bilayer lipid membranes (BLMs) with transmembrane proteins incorporated within them represents a well‐defined system for the analysis of membrane proteins, especially ion channel proteins that are major targets for drug design. Because the BLM system has a high compatibility with recently developed cell‐free expression systems, it has attracted attention as a next‐generation drug screening system. However, three issues associated with BLM systems, i. e., their instability, the need for non‐volatile organic solvents and a low efficiency of ion channel incorporation, have limited their use as a drug screening platform. In this personal account, we discuss our recent approaches to address these issues based on microfabrication. We also discuss the potential for using the BLM system combined with cell‐free expression systems as a drug screening system for future personalized medicine. 相似文献
145.
Seid M. Adem Elisabeth Mansfield John P. Keogh Henry K. Hall Jr. Craig A. Aspinwall 《Analytica chimica acta》2013
Phosphorylcholine (PC) based phospholipid bilayers have proven useful as capillary coating materials due to their inherent resistance to non-specific protein adsorption. The primary limitation of this important class of capillary coatings remains the limited long-term chemical and physical stability of the coatings. Recently, a method for increasing phospholipid coating stability in fused silica capillaries via utilization of polymerized, synthetic phospholipids was reported. Here, we expand upon these studies by investigating polymerized lipid bilayer capillary coatings with respect to separation performance including run-to-run, day-to-day and column-to-column reproducibility and long-term stability. In addition, the effects of pH and capillary inner diameter on polymerized phospholipid coated capillaries were investigated to identify optimized coating conditions. The coatings are stabilized for protein separations across a wide range of pH values (4.0–9.3), a unique property for capillary coating materials. Additionally, smaller inner diameter capillaries (≤50 μm) were found to yield marked enhancements in coating stability and reproducibility compared to wider bore capillaries, demonstrating the importance of capillary size for separations employing polymerized phospholipid coatings. 相似文献
146.
P. G. Kosymbetov R. Kh. Ziyatdinova S. V. Bessonova B. A. Salakhutdinov Dzh. Ziyamov U. N. Zainutdinov T. F. Aripov 《Chemistry of Natural Compounds》2004,40(3):235-240
The ionophoric and complexant properties of synthetic derivatives of lagochilin, 3,18-O-isopropylidenelagochilin and 3,18-O-ethylidenelagochilin, were studied by BLM methods, conductometry, and IR spectroscopy. The ionophoric activity was found to be highly selective for divalent cations. Studies of the electrical conductivity of alkaline-earth metal salts in the presence of the lagochilin derivatives and analysis of their IR spectra have shown that they can form complexes with various ratios of metal ions. 相似文献
147.
In the present work, we report the interplay of single particle and Cooper pair tunnelings on the superconducting state of
layered high-T
c cuprate superconductors. For this we have considered a model Hamiltonian incorporating the intra-planar interactions and
the contributions arising due to the coupling between the planes. The interplanar interactions include the single particle
tunneling as well as the Josephson tunneling of Cooper pairs between the two layers. The expression of the out-of-plane correlation
parameter which describes the hopping of a particle from one layer to another layer in the superconducting state is obtained
within a Bardeen-Cooper-Schriefer (BCS) formalism using the Green’s function technique. This correlation is found to be sensitive
to the various parameter of the model Hamiltonian. We have calculated the out-of-plane contribution to the superconducting
condensation energy. The calculated values of condensation energy are in agreement with those obtained from the specific heat
and the c-axis penetration depth measurements on bilayer cuprates. 相似文献
148.
Yubin Ge Hui Zhou Wei Kong Yi Tong Shuyan Wang Wei Li 《Applied biochemistry and biotechnology》1998,69(1):17-29
Bilayer glucose isomerase was immobilized in porousp-trimethylaminepolystyrene (TMPS) beads through a molecular deposition technique. Some of the factors that influence the activity
of immobilized glucose isomerase were optimized, with the enzyme concentration of 308 IU/mL, enzyme-to-matrix ratio of 924
IU/g wet carrier, and hexamethylene bis(trimethylammonium iodine) concentration of 15 mg/mL giving the maximum catalytic activity
(2238 IU/g dry gel) of the immobilized bilayer glucose isomerase, retaining 68.5% of the initially added activity. The half-life
of the immobilized bilayer glucose isomerase was approx 45 d at pH 8.5, 60°C, with 50% (w/v) glucose as substrate. The specific
productivity of the immobilized bilayer glucose isomerase was 223 g dry D-glucose/g dry immobilized enzyme per d. 相似文献
149.
Jun-Zhong Wang Ke-Hui Wu Wei-Sheng Yang Xing-Jun Wang J.T. Sadowski Y. Fujikawa T. Sakurai 《Surface science》2005,579(1):80-88
Utilizing the substrate of Ga bilayer grown on Si(1 1 1)-√3 × √3-Ga, we have investigated the structural transition of pentacene monolayer induced by moderate annealing. Short-range ordering has been observed in the monolayer pentacene deposited at room temperature. Annealing the sample at ∼350 K produced ordered pentacene monolayer with the “brick-wall” adsorption pattern. The STM images with sub-molecular resolution revealed that the orbital symmetry of the HOMO is reduced from D2h to C2v, due to the substrate-molecule interaction, while the deeper HOMO-1 orbital remains intact. Further annealing at ∼400 K led to the formation of molecular dimers as well as the structural transition from “brick-wall” packing to “herringbone” pattern. 相似文献
150.
Dr. Kouta Sugikawa Tatsuya Kadota Dr. Kazuma Yasuhara Prof. Atsushi Ikeda 《Angewandte Chemie (International ed. in English)》2016,55(12):4059-4063
The behavior of self‐assembly processes of nanoscale particles on plasma membranes can reveal mechanisms of important biofunctions and/or intractable diseases. Self‐assembly of citrate‐coated gold nanoparticles (cAuNPs) on liposomes was investigated. The adsorbed cAuNPs were initially fixed on the liposome surfaces and did not self‐assemble below the phospholipid phase transition temperature (Tm). In contrast, anisotropic cAuNP self‐assembly was observed upon heating of the composite above the Tm, where the phospholipids became fluid. The number of self‐assembled NPs is conveniently controlled by the initial mixing ratio of cAuNPs and liposomes. Gold nanoparticle protecting agents strongly affected the self‐assembly process on the fluidic membrane. 相似文献