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991.
Yulin Ren Sijin Wu Joanna E. Burdette Xiaolin Cheng A. Douglas Kinghorn 《Molecules (Basel, Switzerland)》2021,26(12)
Digoxin is a cardiac glycoside long used to treat congestive heart failure and found recently to show antitumor potential. The hydroxy groups connected at the C-12, C-14, and C-3′a positions; the C-17 unsaturated lactone unit; the conformation of the steroid core; and the C-3 saccharide moiety have been demonstrated as being important for digoxin’s cytotoxicity and interactions with Na+/K+-ATPase. The docking profiles for digoxin and several derivatives and Na+/K+-ATPase were investigated; an additional small Asn130 side pocket was revealed, which could be useful in the design of novel digoxin-like antitumor agents. In addition, the docking scores for digoxin and its derivatives were found to correlate with their cytotoxicity, indicating a potential use of these values in the prediction of the cancer cell cytotoxicity of other cardiac glycosides. Moreover, in these docking studies, digoxin was found to bind to FIH-1 and NF-κB but not HDAC, IAP, and PI3K, suggesting that this cardiac glycoside directly targets FIH-1, Na+/K+-ATPase, and NF-κB to mediate its antitumor potential. Differentially, digoxigenin, the aglycon of digoxin, binds to HDAC and PI3K, but not FIH-1, IAP, Na+/K+-ATPase, and NF-κB, indicating that this compound may target tumor autophagy and metabolism to mediate its antitumor propensity. 相似文献
992.
Zhang Wenyao Zhang Zhizhong Jin Wenqi Zhang Ruonan Cheng Meng Yang Zhihua Pan Shilie 《中国科学:化学(英文版)》2021,64(9):1498-1503
The introduction of oxofluoride anion into anionic group assists to tune optical properties owing to the change of coordination,electronegativity,and according anionic framework.Here,we proposed a rational design of new compounds by fluorine-driven structure and optical property evolution.A new borophosphate Ba_2BP_3O_(11)with the monoclinic space group P2_1/c has been synthesized in the sealed system.Ba_2BP_3O_(11)exhibits a rare P–O–P bridge formation,which is the first example in alkaline-earth metal borophosphates.By further substituting[BO_4]~(3-)with[BO_3F]~(4-),the first alkaline-earth metal/lead fluoroborophosphates M_2BP_2O_8F (M=Ba and Pb) with the same space group were designed.Since the scissors effect of fluorine,in M_2BP_2O_8F (M=Ba and Pb),a BO_3F tetrahedron corner-sharing with three PO_4tetrahedra forms 1D chains along the b-axial direction,which are filled by MO_n(M=Ba/Pb,n=5,6,8) distorted polyhedra.The first principles calculation shows that the borophosphate Ba_2BP_3O_(11)has a birefringence about 0.013@1,064 nm,while the fluoroborophosphates M_2BP_2O_8F (M=Ba and Pb) have the values of 0.035 and 0.043@1,064 nm,respectively.Such an apparent enhancement in birefringence is derived from synergies of the oxyfluoride and cation.The introduction of fluorine-containing heteroanionic groups provides a feasible strategy to design novel promising optical materials. 相似文献
993.
Cheng Fei Xu Yunfei Lv Zhenfei Huang Zhaohui Fang Minghao Liu Yan’gai Wu Xiaowen Min Xin 《Journal of Thermal Analysis and Calorimetry》2021,146(5):2089-2099
Journal of Thermal Analysis and Calorimetry - In this study, we focus on important global issue containing both environmental pollution control and energy saving. High density polyethylene (HDPE)... 相似文献
994.
Qi Cong Ding Zi Tu Jianglin Wang Yuxing Wang Yinjie 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2269-2284
Journal of Thermal Analysis and Calorimetry - As high heat dissipation has increasingly become the primary factor restricting the capability of electronic elements, and the high temperature of the... 相似文献
995.
Díaz-Díaz Ana María López-Beceiro Jorge Li Yanchun Cheng Yi Artiaga Ramón 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3125-3132
Journal of Thermal Analysis and Calorimetry - A model is proposed to fit differential scanning calorimetry (DSC) isothermal crystallization curves obtained from the molten state at different... 相似文献
996.
Yuan Liu Ting Lin Cui Cheng Qiaowen Wang Shujin Lin Chun Liu Xiao Han 《Molecules (Basel, Switzerland)》2021,26(4)
Cyclodextrins (CDs) are a series of cyclic oligosaccharides formed by amylose under the action of CD glucosyltransferase that is produced by Bacillus. After being modified by polymerization, substitution and grafting, high molecular weight cyclodextrin polymers (pCDs) containing multiple CD units can be obtained. pCDs retain the internal hydrophobic-external hydrophilic cavity structure characteristic of CDs, while also possessing the stability of polymer. They are a class of functional polymer materials with strong development potential and have been applied in many fields. This review introduces the research progress of pCDs, including the synthesis of pCDs and their applications in analytical separation science, materials science, and biomedicine. 相似文献
997.
998.
Janus 粒子,也称为阴阳结构粒子或两面性非对称粒子,是指表面上具有两种或两种以上不同化学组成或性质的不对称粒子。目前,Janus 粒子因其独特的结构和功能已经逐渐成为生物医药、催化、材料以及防污等领域中的新型功能材料。在环境检测领域,Janus材料亦因其特殊的光学、磁学及电学性能,为提高检测灵敏度、选择性和稳定性等提供了新的研究方向。基于此,本文主要讨论了Janus材料在环境检测方面的特点、优势和相关应用。最后,本文基于本课题组的研究经验以及工作中所面临的问题,对本领域的发展和未来的研究方向提出了展望,以期对本领域的未来发展提供指导。 相似文献
999.
Shufang Ren Runyan Feng Shounian Cheng Qingtao Wang Zhixiang Zheng 《Electroanalysis》2021,33(6):1471-1483
Ti3C2TX MXene was synthesized by exfoliating pristine Ti3AlC2 phase with hydrofluoric acid. The simple methods of mechanical mixing and drop-casting of Ti3C2TX and MWCNTs were carried out to prepare sensing electrode of Ti3C2TX/MWCNTs/GCE. The composite and topography, especially the surface functional groups of Ti3C2TX/MWCNTs were analyzed by XRD, SEM, FTIR, XPS, and Raman spectrum. The results turned out that Ti3C2TX was characteristic by accordion-like 2D nanostructure with the surfaces terminated with −OH, −F, and =O. When combining with acid pretreated, the interaction between the functional groups of Ti3C2TX and MWCNTs facilitated the convenience and reproducibility of the robust modified electrodes and could make Ti3C2TX/MWCNTs/GCE possess good synergistic catalytic acceleration by increasing the electron transfer efficiency as well as adsorption and aggregation of MOP analyte onto the electrode surface. Versatile electrochemical measurements of CV, DPV and EIS were used to investigate the electrochemical performance of Ti3C2TX/MWCNTs/GCE sensing platform. The linear detection range is 0.01–100 μM with the limit of detection of 0.0092 μM (S/N=3). The sensor has good stability, repeatability, reproducibility and anti-interference. In the detection of serum and urine samples, it has a good recovery rate. 相似文献
1000.