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91.
Ghobad Mohammadi Mohammad Mahdi Zangeneh Akram Zangeneh Zahra Minoosh Siavosh Haghighi 《应用有机金属化学》2020,34(1):e5136
The aim of the recent research was to investigate the anti-breast cancer effects of silver nanoparticles using Phoenix dactylifera seed ethanolic extract (AgNPs). After preparation of Phoenix dactylifera seed extract, GC/MS was performed to detect the compounds. The findings indicated that 9-Octadecenoic acid (Z)- methyl ester (40.95%) and Dodecanoic acid methyl ester (20%) were the most frequent constituents found in P. dactylifera. These nanoparticles were spherical with a size range of 17-19 nm and characterized using various analytical techniques including UV–Vis absorption spectroscopy to determine the presence of AgNPs in the solution. We studied functional groups of P. dactylifera extract in the reduction and capping process of AgNPs by FT-IR, crystallinity and FCC planes by X-ray diffraction (XRD) pattern and surface morphology, shapes, and size of AgNPs by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). DPPH free radical scavenging test was used to test the antioxidant properties of P. dactylifera and AgNPs, which revealed high antioxidant potential similar to butylated hydroxy toluene (BHT) as the positive control. The results of cytotoxicity analysis indicated that P. dactylifera and AgNPs were toxic for MCF-7 cells. In vivo design, induction of breast cancer was done by 7,12-Dimethylbenz[a] anthracene (DMBA) in 50 animals. After 10 days, the animals were randomly divided into six subgroups, including healthy control, untreated control, two groups receiving the P. dactylifera at 2 and 6 mg/kg and two groups receiving the AgNPs at 2 and 6 mg/kg concentrations. Both doses of P. dactylifera and AgNPs (especially AgNPs6) significantly (p ≤ 0.05) reduced the weight and volume of liver, mammary gland, kidney, spleen, ALP, AST, ALT, GGT, cholesterol, LDL, triglyceride, total and conjugated bilirubin, urea, creatinine, glucose, ferrous, ferritin, erythropoietin, GR, IL1, IL6, IL12, IL18, IFNY, and TNFα and increased HDL, total protein, albumin, WBC, lymphocyte, neutrophils, platelet, RBC, Hb, PCV, MCV, MCH, MCHC, SOD, CAT, GPx, IL4, IL5, IL10, IL13, and IFNα compared to the untreated group. Moreover, P. dactylifera and AgNPs (especially AgNPs6) significantly (p ≤ 0.05) treated breast cancer with reduction of organs free of metastasis compared to the untreated group. Seemingly, the AgNPs can be used for the treatment of breast cancer. 相似文献
92.
Nanobiotechnology is a capable technology that deals with nanomaterials in several scientific domains such as medicine, chemistry, nanotechnology, and biotechnology. In this scale, remarkable differences are seen in many properties of materials that are not observed on a larger scale. In this regard, pharmacologists have tried to synthesize many supplements and drugs from the nanoparticles. The present study confirms the ability of aqueous extract of Hibiscus sabdariffa grown under in vitro condition for the biosynthesis of gold nanoparticles (AuNPs). Also, in this study, we revealed the anti-acute myeloid leukemia activity of AuNPs compared to daunorubicin in a leukemic rodent model. These nanoparticles were characterized by fourier-transform infrared spectroscopy (FT-IR) spectroscopy, ultraviolet–visible spectroscopy (UV–Vis.), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM) analysis. TEM and FE-SEM images exhibited a uniform spherical morphology and diameters of 15-45 nm for the biosynthesized nanoparticles. In vivo design, induction of acute myeloid leukemia was done by 7,12-Dimethylbenz[a]anthracene (DMBA) in 75 mice. Then, the animals were randomly divided into six subgroups, including HAuCl4, H. sabdariffa, AuNPs, daunorubicin, untreated, and control. AuNPs similar to daunorubicin, significantly (P ≤ .05) reduced the pro-inflammatory cytokines (IL1, IL6, IL12, IL18, IFNY, and TNFα), and the total white blood cell (WBC), blast, monocyte, neutrophil, eosinophil, and basophil counts and enhanced the anti-inflammatory cytokines (IL4, IL5, IL10, IL13, and IFNα) and the platelet, lymphocyte, and red blood cell (RBC) parameters as compared to the untreated mice. By quantitative real-time polymerase chain reaction, sphingosine-1-phosphate receptor-1 and sphingosine-1-phosphate receptor-5 mRNA expression in lymphocytes were significantly (P ≤ .05) raised by treating the leukemic mice with the AuNPs and daunorubicin. In vitro design, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test revealed similar antioxidant potentials for daunorubicin and AuNPs. Besides, AuNPs similar to daunorubicin had low cell viability dose-dependently against Murine C1498, Human HL-60/vcr, and 32D-FLT3-ITD cell lines without any cytotoxicity on HUVEC cell line. In conclusion, the results of chemical characterization confirm that the H. sabdariffa flower can be used to produce gold nanoparticles with a remarkable amount of anti-acute myeloid leukemia effect. 相似文献
93.
Rhodium/chiral diene-catalyzed asymmetric methylation of N-sulfonylarylimines with trimethylboroxine
Takahiro Nishimura Akram Ashouri Yusuke Ebe Yuko Maeda Tamio Hayashi 《Tetrahedron: Asymmetry》2012,23(9):655-658
A hydroxorhodium complex coordinated with a chiral diene ligand catalyzed the asymmetric addition of trimethylboroxine to N-sulfonylarylimines to give high yields of chiral 1-aryl-1-ethylamines with high enantioselectivity. 相似文献
94.
We present a quantum CNOT logic gate based on interaction of a three-level cesium atom with a two-mode electromagnetic field
in a high-Q superconducting cavity. The three-level atom acts as a control qubit and the two-mode electromagnetic field serves as a target
qubit. Presently available QED experiments make it feasible to realize the theoretical suggestion in the laboratory. We determine
the feasibility of our proposal by calculating the fidelity. 相似文献
95.
The effect of cationic micelles of cetyltrimethylammonium bromide (CTAB) on the kinetics of interaction of copper dipeptide complex [Cu(II)‐Gly‐Gly]+ with ninhydrin has been studied spectrophotometrically at 70°C and pH 5.0. The reaction follows first‐ and fractional‐order kinetics, respectively, in complex and ninhydrin. The reaction is catalyzed by CTAB micelles, and the maximum rate enhancement is about twofold. The results obtained in the micellar medium are treated quantitatively in terms of the kinetic pseudophase and Piszkiewicz models. The rate constants (kobs or kΨ), micellar‐binding constants (kS for [Cu(II)‐Gly‐Gly]+, kN for ninhydrin), and index of cooperativity (n) have been evaluated. A mechanism is proposed in accordance with the experimental results. The influence of different inorganic (NaCl, NaBr, Na2SO4) and organic (NaBenz, NaSal) salts on the reaction rate has also been seen, and it is found that tightly bound/incorporated counterions are the most effective. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 556–564, 2007 相似文献
96.
Javed Akram 《Annalen der Physik》2023,535(2):2200511
This study examines the possibility of finding perfect entanglers for a Hamiltonian which corresponds to several quantum information platforms of interest at the present time. However, in this study, a superconducting circuit is used that stands out from other quantum-computing devices, especially because transmon qubits can be coupled via capacitors or microwave cavities, which enables to combine high coherence, fast gates, and high flexibility in its design parameters. There are currently two factors limiting the performance of superconducting processors: timing mismatch and the limitation of entangling gates to two qubits. In this work, a two-qubit SWAP and a three-qubit Fredkin gate is presented, additionally, a perfect adiabatic entanglement generation between two and three programmable superconducting qubits is also demonstrated. Furthermore, the impact of random dephasing, emission, and absorption noises on the quantum gates and entanglement is also demonstrated in this study. It is demonstrated by numerical simulation that CSWAP gate and W-state generation can be achieved perfectly in one step with high reliability under weak coupling conditions. Hence, this scheme could contribute to quantum teleportation, quantum communication, and some other areas of quantum information processing. 相似文献
97.
Akram M. El-Didamony Eman A.H. Erfan 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):1138-1145
Three simple, accurate and sensitive methods (A–C) for the spectrophotometric assay of captopril (CPL) in bulk drug, in dosage forms and in the presence of its oxidative degradates have been described. The methods are based on the bromination of captopril with a solution of excess brominating mixture in hydrochloric acid medium. After bromination, the excess brominating mixture is followed by the estimation of surplus bromine by three different reaction schemes. In the first method (A), the determination of the residual bromine is based on its ability to bleach the indigo carmine dye and measuring the absorbance at 610 nm. Method B, involves treating the unreacted bromine with a measured excess of iron(II) and the remaining iron(II) is complexed with 1,10-phenanthroline and the increase in absorbance is measured at 510 nm. In method (C), the surplus bromine is treated with excess of iron(II) and the resulting iron(III) is complexed with thiocyanate and the absorbance is measured at 478 nm. In all the methods, the amount of bromine reacted corresponds to the drug content. The different experimental parameters affecting the development and stability of the color are carefully studied and optimized. Beer's law is valid within a concentration range of 0.4–6.0, 0.4–2.8 and 1.2–4.8 μg mL?1 for methods A, B and C, respectively. The calculated apparent molar absorptivity was found to be 5.16 × 104, 9.95 × 104 and 1.74 × 105 L mol?1 cm?1, for methods A, B and C, respectively. Sandell's sensitivity, correlation coefficients, detection and quantification limits are also reported. No interference was observed from common additives found in pharmaceutical preparations. The proposed methods are successfully applied to the determination of CPL in the tablet formulations with mean recoveries of 99.94–100.11% and the results were statistically compared with those of a reference method by applying Student's t- and F-test. 相似文献
98.
In this Letter, we create an optical nanoantenna array composed of parasitic plasmonic loops that can enhance radiation characteristics and direct the optical energy successfully. Three metallic loops inspired by the concept of the Yagi-Uda antenna are optimized around the region where they feature high scattering performance to control the radiation beam. The loop geometry, when compared to the dipole configuration, has the benefit of using the available aperture in an effective way to provide higher directivity. The angular emission of the nanoloop array antenna is highly directive, and a directivity of 8.2 dB for upward radiation is established. 相似文献
99.
Akram Lbekkouri 《Archiv der Mathematik》2009,93(4):331-344
Let p be an odd prime number, and let Q p be the field of rational p-adic numbers.The aim of this work is the determination of the standard form of an Eisenstein polynomial defining a normal wildly ramified extension of Q p . We prove first the equivalence between normality and cyclicity, give some essential normality conditions for the general case (degree p n ), then we solve the problem completely for the case (degree p 2) also, we obtain that the normality depends on seven congruences modulo p m between the coefficients of the considered polynomial with just m = 2 or 3. Note that the case (degree p) was solved by Öystein Ore (see Math. Annalen 102 (1930), 283–304). Also examples are given. 相似文献
100.
In this paper, the evolution equations with nonlinear term describing the resonance interaction between the long wave and
the short wave are studied. The semi-discrete and fully discrete Crank-Nicholson Fourier spectral schemes are given. An energy
estimation method is used to obtain error estimates for the approximate solutions. The numerical results obtained are compared
with exact solution and found to be in good agreement. 相似文献