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61.
Sahar Salari Ali Neamati Masoud Homayouni Tabrizi Seyed Mohammad Reza Seyedi 《应用有机金属化学》2020,34(3):e5417
There are many types of researches investigating anticancer therapeutics for breast cancer therapy. Zinc oxide nanoparticles (ZnONPs) as an efficient drug delivery system, has been widely being used in various biomedical applications. In the current study, we synthesized ZnONP applying Rheum rhaponticum Waste (RRW) as a novel bio-platform to investigate its anticancer impacts on MCF7 breast cancer cells compared with normal Human HFF and HDF cells. In this regard, RRW was triggered to synthesize the ZnONPs. Then, they were characterized by XRD, FTIR, TEM, and SEM analysis. Next, the MCF-7, HFF, and HDF cell lines were cultured and treated as the following plane: Incubation of all cell lines for 72, 48, and 24 hours at the presence of different ZnONPs doses. Finally, the cell morphology, BCL2- BAX genes expression profile and AO/PI-fluorescent cell staining on the 48-hour incubated cells were analyzed to check the ZnONP apoptotic activity. Moreover, the ZnONP antioxidant activity was analyzed by a DPPH antioxidant test. We produced the 30 nm ZnONPs which significantly increased the BAX and decreased the BCL-2 gene expression. According to the results including the Sub G1 enhancement peaks, apoptotic hallmarks, MTT assay, and the AO/PI-fluorescent stained cells, ZnONPs can specifically induce apoptotic death in MCF7 breast cancer cells compared with normal HFF and HDF cells. The IC50 values of MCF-7 in 72, 48, and 24 hr were measured at 8, 11, and 12 μg/ml in 72, 48, and 24 hr, respectively. This is while the mentioned values in the normal cells (HFF, HDF) were estimated at higher treatment doses. In conclusion, we suggest that the ZnONPs have the potential to be applied as a safe cell-specific apoptosis inducer in breast cancer treatment. However, there are many challenges that need to be clarified for applying them as an efficient anticancer agent. 相似文献
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A robust and highly water stable series of UiO-66-drived MOFs including UiO-66-NH2, glycidyl methacrylate functionalized UiO-66-NH2 (UiO-66-GMA) and ethylenediamine functionalized UiO-66-NH2 (UiO-66-EDA) were synthesized solvothermally and studied their adsorption performances toward two anti-cancer drugs, methotrexate (MTX) and curcumin (CUR) in the case of overdose. It was found that functionalizing the surface of UiO-66-NH2 nanoparticles with different functional groups remarkably changes the adsorption capacity and the ideal adsorption selectivity of MTX over CUR. Particularly, the UiO-66-EDA exhibited the highest adsorption capacities for both drugs, 540.78 and 423.85 mg/g for MTX and CUR, respectively, because of the strong interaction between drug molecules and adsorbent via hydrogen bonding due to the existence of different polar functional groups. The kinetics of drugs adsorption was investigated by three well-known kinetic models, which the output indicates that the adsorption of both drugs onto the synthesized MOFs follow the pseudo-second-order model. Moreover, it was found that the equilibrium adsorption results were well fitted with the Langmuir isotherm models, revealing that the adsorption of both drugs onto the synthesized MOFs is a monolayer adsorption process. Further investigation illustrated that the synthesized MOFs could be easily activated and reused after four successive adsorption–desorption cycles. The output of the present work is of main important for biomedical and environmental applications of MOFs as an outstanding adsorbent for adsorption removal of hazardous drugs from contaminated aqueous solutions. 相似文献
63.
A series of gold(I) complexes of ligand ibuprofen-alkynyl (but-3-yn-1-yl 2-(4-isobutylphenyl)propanoate, LE) with N-heterocyclic carbene (LC: 1,3-dimethylimidazol-2-ylidene) and triphenylphosphine (PPh3) ligands with formula (LE)Au (LC) (complex 1 ) and (LE)Au (PPh3) (complex 2 ) were synthesized and fully characterized by spectroscopic methods. In order to reveal the cytotoxicity mechanism, the interaction of complex 1 or 2 with cysteine (HCys) has been studied by experimental and density functional theory (DFT) methods. The compounds were investigated for their anticancer activity against MCF-7, MDAMB 231 breast cancer cells, HT-29 colon cancer cells and MCF-10A non-tumor breast cell line. The results were compared with cisplatin and auranofin as reference drugs. The complex 2 showed more cytotoxic activity than complex 1 . The complex 2 was 4.2, 3.7, and 1.7 fold more active than cisplatin against HT-29, MDA-MB-231, MCF-7 cancer cell lines, respectively. The inhibition of thioredoxin reductase of complexes 1 and 2 including cytosolic (TrxR1) and mitochondrial (TrxR2) thioredoxin reductase and also the inhibition of glutathione reductase (GR) were studied in detail. Moreover, the cellular uptake and reactive oxygen species (ROS) generation of compounds were investigated. Based on the DFT calculations a relationship between the σ-donor ability of the isolated ligands and cytotoxicity is suggested. 相似文献
64.
We report the wavelength conversion based on double-pass cascaded nonlinear interaction (χ(2):χ(2)) of sum and difference frequency generation in quasi-phase matched lithium niobate waveguides and compare it with double-pass cascaded second harmonic generation and difference frequency generation with and without waveguide loss. It is shown that the efficiency decreases considerably even for the low-loss waveguide compared to the lossless one especially for long waveguides and to achieve the higher efficiency for the same length, the amount of the extra power to compensate the loss increases. Also, an increased detuning of pump wavelength is proposed to flatten the response with a small efficiency penalty. The detuning- and loss-compensating pump powers can be found using the design diagrams in which the criteria for the design of waveguide length and the assignment of pumps power to obtain the desired efficiency, ripple and bandwidth are presented assuming a 75-nm pump wavelength difference. 相似文献
65.
Kinetics of heterogeneous photocatalytic degradation of reactive dyes in an immobilized TiO2 photocatalytic reactor 总被引:1,自引:0,他引:1
Mahmoodi NM Arami M Limaee NY Tabrizi NS 《Journal of colloid and interface science》2006,295(1):159-164
The photocatalytic degradation of two reactive dyes has been investigated by UV/TiO2/H2O2 using an immobilized TiO2 photocatalytic reactor. Reactive Blue 8 (RB 8) and Reactive Blue 220 (RB 220) textile dyes were used as model compounds. Photocatalytic degradation processes were performed using a 5-L solution containing dyes. The initial concentrations of dyes were 50 mg/L. The radiation source was two 15 W UV-C lamps. A batch mode immersion photocatalytic reactor was utilized. UV-vis and ion chromatography (IC) analyses were employed to obtain the details of the photodegradation of the selected dyes. Colored synthetic waters were completely decolorized in relatively short time after UV irradiation in the presence of various concentrations of hydrogen peroxide. Formate, acetate, oxalate, and glyoxylate anions were detected as dominant aliphatic intermediates where they were further oxidized slowly to CO2. The UV/TiO2/H2O2 process was able to oxidize the dyes with partial mineralization of carbon, nitrogen, and sulfur heteroatoms into CO2, NO3-, and SO4(2-), respectively. Kinetics analysis indicates that the photocatalytic decolorization rates of the dye can be approximated by a pseudo-first-order model. The UV/TiO2/H2O2 process proved to be capable of decolorization and mineralization of the reactive dyes (RB 8 and RB 220). 相似文献
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67.
Evaluation of UiO‐66 metal organic framework as an effective sorbent for Curcumin's overdose 下载免费PDF全文
Hossein Molavi Mostafa Zamani Mozhgan Aghajanzadeh Hamidreza Kheiri Manjili Hossein Danafar Akbar Shojaei 《应用有机金属化学》2018,32(4)
Metal organic frameworks (MOFs) UiO‐66 (UiO stands for University of Oslo) and NH2‐UiO‐66 were prepared and characterized as sorbent (antidotal agents) for curcumin (CUR) adsorption. The structure of products were characterized by X‐ray powder diffraction (XRD), Field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Attenuated Total Reflectance‐Fourier transform infrared spectroscopy (ATR‐FTIR), and N2 adsorption–desorption measurements. FESEM showed NH2‐UiO‐66 displayed symmetrical crystals with triangular base pyramid morphology, with the particle size around 100 nm and uniform size distribution. Adsorption capacities of CUR/MOFs with different mass ratios in the feed were investigated in the present study, and this investigation revealed that when the CUR/MOFs with mass ratio was around 0.4, the absorption capacity of NH2‐UiO‐66 had tended to maximum. Although, functionalization reduced the specific surface area and free volume, introducing polar amine groups could improve the affinity of NH2‐UiO‐66 respect to CUR. Kinetic studies showed that the kinetic data are well fitted with the pseudo‐ second‐order model. MTT assay revealed that MOFs at the concentration range of 0–560 μg/ml had no cytotoxic effect on the Human Foreskin Fibroblast normal cell line (HFF‐2). These results suggest that these MOFs could be safe as sorbent for adsorb CUR from the body. 相似文献
68.
Force field parametrization and molecular dynamics simulation of flexible POSS-linked (NHC; phosphine) Ru catalytic complexes 总被引:1,自引:0,他引:1
Ahmadi A McBride C Freire JJ Kajetanowicz A Czaban J Grela K 《The journal of physical chemistry. A》2011,115(43):12017-12024
In recent years, N-heterocyclic carbene (NHC) or phospine groups have been put forward as candidate catalysts ligands for olefin metathesis reactions to be performed using multistep methods. Some of these proposed ligands contain polyhedral oligomeric silsesquioxane (POSS) structures linked to NHC rings by means of alkyl chains. Some important properties for the prediction of catalytic activity, such as the theoretically defined buried volume, are related to the conformational characteristics of these complex ligands that can be studied through molecular dynamics simulations. However, the chemical structure of resulting catalytic complexes usually contains atoms or groups that are not included in the common forcefields used in simulations. In this work we focus on complexes formed by a catalytic metal center (Ru) with both phospine and POSS-linked NHC groups. The central part of the complexes contain atoms and groups that have bonds, bond angles, and torsional angles whose parameters have not been previously evaluated and included in existing force fields. We have performed basic ab initio quantum mechanical calculations based on the density functional theory to obtain energies for this central section. The force field parameters for bonds, bond angles, and torsional angles are then calculated from an analysis of energies calculated for the equilibrium and different locally deformed structures. Nonbonded interactions are also conveniently evaluated. From subsequent molecular dynamics simulations, we have obtained results that illustrate the conformational characteristics most closely connected with the catalytic activity. 相似文献
69.
Feasibility of an electron-based crystalline undulator 总被引:3,自引:0,他引:3
The feasibility to generate powerful monochromatic radiation of the undulator type in the gamma region of the spectrum by means of planar channeling of ultrarelativistic electrons in a periodically bent crystal is proven. It is shown that to overcome the restriction due to the smallness of the dechanneling length, an electron-based crystalline undulator must operate in the regime of higher beam energies than a positron-based one does. A numerical analysis is performed for a 50 GeV electron channeling in Si along the (111) crystallographic planes. 相似文献
70.
James E. Butler Anatoly Vikharev Alexei Gorbachev Mikhail Lobaev Anatoly Muchnikov Dmitry Radischev Vladimir Isaev Valerii Chernov Sergey Bogdanov Mikail Drozdov Evgeniy Demidov Ekaterina Surovegina Vladimir Shashkin Albert Davydov Haiyan Tan Louisa Meshi Alexander C. Pakpour‐Tabrizi Marie‐Laure Hicks Richard B. Jackman 《固体物理学:研究快报》2017,11(1)
Diamond is desired for active semiconducting device because of it high carrier mobility, high voltage breakdown resistance, and high thermal diffusivity. Exploiting diamond as a semiconductor is hampered by the lack of shallow dopants to create sufficient electronic carriers at room temperature. In this work, nanometer thick, heavily boron doped epitaxial diamond ‘delta doped’ layers have been grown on ultra smooth diamond surfaces which demonstrate p type conduction with enhanced Hall mobilities of up to 120 cm2/Vs and sheet carrier concentrations to 6 × 1013 cm–2, thus enabling a new class of active diamond electronic devices. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献