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51.
Nada Abdullah Yahya Tamimi Sergey Dobretsov Najwa Al Balushi Jalila Alshekaili Hamed Al Balushi Mahmood Al Kindi Syed Imran Hassan Shadia Al Bahlani Benjamin K. Tsang Ikram A. Burney 《Molecules (Basel, Switzerland)》2021,26(12)
High-grade epithelial ovarian cancer is a fatal disease in women frequently associated with drug resistance and poor outcomes. We previously demonstrated that a marine-derived compound MalforminA1 (MA1) was cytotoxic for the breast cancer cell line MCF-7. In this study, we aimed to examine the effect of MA1 on human ovarian cancer cells. The potential cytotoxicity of MA1was tested on cisplatin-sensitive (A2780S) and cisplatin-resistant (A2780CP) ovarian cancer cell lines using AlamarBlue assay, Hoechst dye, flow cytometry, Western blot, and RT-qPCR. MA1 had higher cytotoxic activity on A2780S (IC50 = 0.23 µM) and A2780CP (IC50 = 0.34 µM) cell lines when compared to cisplatin (IC50 = 31.4 µM and 76.9 µM, respectively). Flow cytometry analysis confirmed the cytotoxic effect of MA1. The synergistic effect of the two drugs was obvious, since only 13% of A2780S and 7% of A2780CP cells remained alive after 24 h of treatment with both MA1 and cisplatin. Moreover, we examined the expression of bcl2, p53, caspase3/9 genes at RNA and protein levels using RT-qPCR and Western blot, respectively, to figure out the cell death mechanism induced by MA1. A significant down-regulation in bcl2 and p53 genes was observed in treated cells compared to non-treated cells (p < 0.05), suggesting that MA1 may not follow the canonical pathway to induce apoptosis in ovarian cancer cell lines. MalforminA1 showed promising anticancer activity by inducing cytotoxicity in cisplatin-sensitive and cisplatin-resistant cancer cell lines. Interestingly, a synergistic effect was observed when MA1 was combined with cisplatin, leading to it overcoming its resistance to cisplatin. 相似文献
52.
In the last few decades, there has been an increasing trend for the usage of natural products and their derivatives as green and renewable oil-filed chemicals. Use of these compounds or their derivatives contributes to reducing the use of traditional chemicals, and enhances green chemistry principles. Curcumin (CRC) is one of the most popular natural products and is widely available. The green character, antioxidant action, and low cost of CRC prompt its use in several applications. In the present study, Curcumin was used to synthesize two new amphiphilic ionic liquids (AILs) by reacting with 1,3-propanesultone or bromoacetic acid to produce corresponding sulfonic and carboxylic acids, CRC-PS and CRC-BA, respectively. Following this, the formed CRC-PS and CRC-BA were allowed to react with 12-(2-hydroxyethyl)-15-(4-nonylphenoxy)-3,6,9-trioxa-12-azapentadecane-1,14-diol (HNTA) to form corresponding AILs, GCP-IL and GRB-IL, respectively. The chemical structures, surface tension, interfacial tension, and relative solubility number (RSN) of the synthesized AILs were investigated. The efficiency of GCP-IL and GRB-IL to demulsify water in heavy crude oil (W/O) emulsions was also investigated, where we observed that both GCP-IL and GRB-IL served as high-efficiency demulsifiers and the efficiency increased with a decreased ratio of water in W/O emulsion. Moreover, the data showed an increased efficiency of these AILs with an increased concentration. Among the two AILs, under testing conditions, GCP-IL exhibited a higher efficiency, shorter demulsification time, and cleaner demulsified water. 相似文献
53.
A one-pot multicomponent synthesis of a novel class of cyanophenylamino-acetamides through the conversion of primary amides to the corresponding nitriles, starting from simple and readily available inputs including 2-aminobenzamide, an aldehyde, and an isocyanide in the presence of p-toluenesulfonic acid as a catalyst, in excellent yields at room temperature in ethanol as a green reaction medium is described. 相似文献
54.
Ali Naghipour Zahra Haji Ghasemi David Morales-Morales Juan M. Serrano-Becerra Craig M. Jensen 《Polyhedron》2008
The asymmetric PCP pincer ligand [C6H4-1-(CH2PPh2)-3-(CH(CH3)PPh2)] (4) has been synthesized in a facile manner in three simple steps in high yield. Metallation of PCP pincer ligand (4) with [Pd(COD)Cl2] affords complex [PdCl{C6H3-2-(CH2PPh2)-6-(CH(CH3)PPh2)}] (7) in good yield. 相似文献
55.
Anham Zafar Dr. Imtiaz-ud-Din Dr. Robert G. Palgrave Dr. Haji Muhammad Dr. Sammer Yousuf Tim Evans 《ChemistryOpen》2023,12(1):e202200229
A series of imidazolium-based symmetrical and asymmetrical dicationic ionic liquids (DcILs) with alkyl spacers of different length and with [FeCl3Br]− as counter ion have been synthesized. The synthesized DcILs are characterized by using FTIR and Raman spectroscopy as well as mass spectrometry, along with single-crystal XRD analysis. Physicochemical properties such as solubility, thermal stability and magnetic susceptibility are also measured. These compounds show low melting points, good solubility in water and organic solvents, thermal stability, and paramagnetism. The products of molar susceptibility and temperature (χmol⋅T) for the synthesized DcILs have been found between 4.05 to 4.79 emu mol−1 K Oe−1 and effective magnetic moment values have also been determined to be compared to that expected from the spin-only approximation. 相似文献
56.
Shima Majidansari Negin Vahedi Mahmood Rekabgardan Camellia Ganjoury Najmeh Najmoddin Mohammad Tabatabaei Faraz Sigaroodi Paniz Naraghi-Bagherpour Seyed Amir Ali Taheri Mohammad-Mehdi Khani 《先进技术聚合物》2023,34(2):740-747
Cardiovascular diseases have always been one of the main causes of death worldwide and eventually one of the major medical concerns. Tissue engineering is promising strategies of treating cardiovascular, which can be an effective approach with the design of appropriate scaffold. In this study, to develop engineering basement membrane for endothelial differentiation with good cell attachment, we produced polycaprolactone (PCL)/poly (glycerol sebacate) (PGS)/gelatin nanofibrous scaffold via electrospinning. Attenuated total reflectance-Fourier transform infrared and the proton nuclear magnetic resonance results confirmed the chemical structure of synthesized PGS. Scanning electron microscope images of the electrospun scaffold revealed that the nanofibers are smooth, continues and uniform. Moreover, due to the presence of hydrophilic functional groups in the scaffold, the contact angle is in the appropriate range for cell adhesion especially endothelial cells. The elastic modulus and ultimate tensile stress of electrospun scaffold were calculated 1.32 ± 0.27 MPa and 1.23 ± 0.18 MPa respectively. Quantitative polymerase chain reaction was performed for evaluation of endothelial differentiation of mesenchymal stem cells cultured on standard plate and fibrous scaffold under chemical stimulation with growth factor. Specific endothelial gene expression results postulated that our modified scaffold could support and significantly promote endothelial differentiation of MSCs. 相似文献
57.
Solid Phase Extraction and Flame Atomic Absorption Spectrometric Determination of Trace Amounts of Zinc and Cobalt Ions in Water Samples 总被引:1,自引:0,他引:1
A simple and rapid method for the preconcentration of Co2+ and Zn2+ as their 2-guanidino-benzimidazole chelates is proposed using an octadecyl silica cartridge. The retained analytes were recovered with a mixture of 5mL of 0.01M HNO3 and 5mL of methanol. The metal ions in the effluent were determined by flame atomic absorption spectrometry. The effect of different parameters, such as sample matrix, amount of ligand, type of eluent for elution of ions from cartridge, flow rates of sample solution and eluent, breakthrough volume, and limit of detection, were evaluated. The effects of various cationic and anionic interferences on the percent recovery of Co2+ and Zn2+ were also studied. Quantitative extraction efficiencies were obtained by elution of the cartridge with a minimal amount of solvent. Hence, with a typical preconcentration factor of 50, the limits of detections of the proposed method are 0.26 and 1.62ngmL–1 for Zn2+ and Co2+, respectively. The method was applied to the determination of zinc and cobalt ions in different water samples. 相似文献
58.
Hua-Hua Wang Yi-Yu Jiang Mian HR Mahmood Hai-Yang Liu Herman H.Y. Sung Ian D. Williams Chi K. Chang 《中国化学快报》2015,26(5):529-533
Tetrakis(alloxycarbonyl)porphyrin and its β-octafluoro-substituted derivatives were synthesized via Lindsey method and transformed to their zinc complexes.Single crystal X-ray structures of corresponding Zn(Ⅱ) porphyrins revealed that β-octafluorination will give more compactness of porphyrin moieties in the crystal structure owing to the hydrogen bonding interactions involving β-fluorine atoms.An unusual six-coordinated Zn(Ⅱ) was found via intramolecular coordination of oxygen atom of meso-substituents with central Zn(Ⅱ). 相似文献
59.
Xin‐Yi Huang Xia Zhang Dong Pei Jian‐Fei Liu Yuan Gong Haji Akber Aisa Duo‐Long Di 《Journal of separation science》2019,42(11):2080-2088
In this work, a continuous high‐speed countercurrent chromatography method has been developed on the basis of elution‐extrusion mode and this method was successfully applied to the separation of maslinic and oleanolic acid from the extract of olive pulp. In the process of ‘elution’, the sample solution was continuously loaded into the column and the maslinic acid was steadily eluted out in this step while highly retained oleanlic acid always stayed in the column. In the process of ‘extrusion’, the oleanlic acid was pushed out of the column with the stationary phase. In this way, we achieved a large sample loading. A total of 120 mL sample solution (about 89.55% of the column volume) which contains 600 mg olive pulp extract was pumped in the apparatus by a constant‐flow pump and the maslinic and oleanolic acids were largely separated within 120 min. Both of these two compounds presented high yields and high purities (271.6 mg for maslinic acid with 86.7% and 83.9 mg oleanolic acids with 83.4%). 相似文献
60.
Hossein Tavallali Hossein Malekzadeh Mohammad Ali Karimi Mahmood Payehghadr Gohar Deilamy-Rad Mahboobeh Tabandeh 《Arabian Journal of Chemistry》2019,12(7):1487-1495
Multi-walled carbon nanotubes (MWCNTs) were chemically functionalized by glutaric dihydrazide (GDH) and characterized with FT-IR technique. This new sorbent was used for enrichment and preconcentration of Co(II), Cd(II), Pb(II), and Pd(II) ions. The adsorption was achieved quantitatively on MWCNTs at pH 4.0, and then the retained metal ions on the adsorbent were eluted with 1.5 mol L?1 HNO3. The effects of analytical parameters including pH of the solution, eluent type, sample volume, and matrix ions were investigated for optimization of the presented procedure. The adsorption capacity of the adsorbent at optimum conditions was found to be 33.6, 29.2, 22.1, and 36.0 mg g?1 for Co(II), Cd(II), Pb(II), and Pd(II), respectively. The LOD values of the method were 0.16, 0.19, 0.17, and 0.12 ng mL?1 (3Sb, n = 10) for Co(II), Cd(II), Pb(II), and Pd(II), respectively. The RSDs values of the method were 0.75, 0.85, 1.16, and 1.30 ng mL?1 for Co(II), Cd(II), Pb(II), and Pd(II), respectively. The method was applied for the determination of analytes in soil, well water, and wastewater samples with satisfactory results. 相似文献