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951.
Qiang Fu Xianjie Wang Jiecai Han Jun Zhong Tongrui Zhang Tai Yao Chengyan Xu Tangling Gao Shibo Xi Ce Liang Lingling Xu Ping Xu Bo Song 《Angewandte Chemie (International ed. in English)》2021,60(1):259-267
To ensure sustainable hydrogen production by water electrolysis, robust, earth‐abundant, and high‐efficient electrocatalysts are required. Constructing a hybrid system could lead to further improvement in electrocatalytic activity. Interface engineering in composite catalysts is thus critical to determine the performance, and the phase‐junction interface should improve the catalytic activity. Here, we show that nickel diphosphide phase junction (c‐NiP2/m‐NiP2) is an effective electrocatalyst for hydrogen production in alkaline media. The overpotential (at 10 mA cm?2) for NiP2‐650 (c/m) in alkaline media could be significantly reduced by 26 % and 96 % compared with c‐NiP2 and m‐NiP2, respectively. The enhancement of catalytic activity should be attributed to the strong water dissociation ability and the rearrangement of electrons around the phase junction, which markedly improved the Volmer step and benefited the reduction process of adsorbed protons. 相似文献
952.
Shicheng Hou Shishao Liang Chao Zhang Yingmei Han Jianhui Liang Hongyu Hu Xingeng Zhang Chun Hu Xiaoping Liu Hong Zhang 《Molecules (Basel, Switzerland)》2021,26(12)
The development of cancer treatments requires continuous exploration and improvement, in which the discovery of new drugs for the treatment of cancer is still an important pathway. In this study, based on the molecular hybridization strategy, a new structural framework with an N-aryl-N’-arylmethylurea scaffold was designed, and 16 new target compounds were synthesized and evaluated for their antiproliferative activities against four different cancer cell lines A549, MCF7, HCT116, PC3, and human liver normal cell line HL7702. The results have shown seven compounds with 1-methylpiperidin-4-yl groups having excellent activities against all four cancer cell lines, and they exhibited scarcely any activities against HL7702. Among them, compound 9b and 9d showed greatly excellent activity against the four kinds of cells, and the IC50 for MCF7 and PC3 cell lines were even less than 3 μM. 相似文献
953.
Joshua Silva Eileen Carry Chen Xue Jifeng Zhang Jing Liang Jacques Y. Roberge Daryl L. Davies 《Molecules (Basel, Switzerland)》2021,26(6)
Alcohol use disorder (AUD) affects over 18 million people in the US. Unfortunately, pharmacotherapies available for AUD have limited clinical success and are under prescribed. Previously, we established that avermectin compounds (ivermectin [IVM] and moxidectin) reduce alcohol (ethanol/EtOH) consumption in mice, but these effects are limited by P-glycoprotein (Pgp/ABCB1) efflux. The current study tested the hypothesis that dihydromyricetin (DHM), a natural product suggested to inhibit Pgp, will enhance IVM potency as measured by changes in EtOH consumption. Using a within-subjects study design and two-bottle choice study, we tested the combination of DHM (10 mg/kg; i.p.) and IVM (0.5–2.5 mg/kg; i.p.) on EtOH intake and preference in male and female C57BL/6J mice. We also conducted molecular modeling studies of DHM with the nucleotide-binding domain of human Pgp that identified key binding residues associated with Pgp inhibition. We found that DHM increased the potency of IVM in reducing EtOH consumption, resulting in significant effects at the 1.0 mg/kg dose. This combination supports our hypothesis that inhibiting Pgp improves the potency of IVM in reducing EtOH consumption. Collectively, we demonstrate the feasibility of this novel combinatorial approach in reducing EtOH consumption and illustrate the utility of DHM in a novel combinatorial approach. 相似文献
954.
Shin-Hun Juang Min-Tsang Hsieh Pei-Ling Hsu Ju-Ling Chen Hui-Kang Liu Fong-Pin Liang Sheng-Chu Kuo Chen-Yuan Chiu Shing-Hwa Liu Chen-Hsi Chou Tian-Shung Wu Hsin-Yi Hung 《Molecules (Basel, Switzerland)》2021,26(1)
Constitutive androstane receptor (CAR) activation has found to ameliorate diabetes in animal models. However, no CAR agonists are available clinically. Therefore, a safe and effective CAR activator would be an alternative option. In this study, sixty courmarin derivatives either synthesized or purified from Artemisia capillaris were screened for CAR activation activity. Chemical modifications were on position 5,6,7,8 with mono-, di-, tri-, or tetra-substitutions. Among all the compounds subjected for in vitro CAR activation screening, 6,7-diprenoxycoumarin was the most effective and was selected for further preclinical studies. Chemical modification on the 6 position and unsaturated chains were generally beneficial. Electron-withdrawn groups as well as long unsaturated chains were hazardous to the activity. Mechanism of action studies showed that CAR activation of 6,7-diprenoxycoumarin might be through the inhibition of EGFR signaling and upregulating PP2Ac methylation. To sum up, modification mimicking natural occurring coumarins shed light on CAR studies and the established screening system provides a rapid method for the discovery and development of CAR activators. In addition, one CAR activator, scoparone, did showed anti-diabetes effect in db/db mice without elevation of insulin levels. 相似文献
955.
Nasopharyngeal carcinoma (NPC) frequently occurs in Southern China. The main treatments of NPC are chemotherapy and radiotherapy. However, chemo-resistance arises as a big obstacle in treating NPC. Therefore, there is a great need to develop new compounds that could reverse tumor drug resistance. In this study, eight matrine derivatives containing thiophene group were designed and synthesized. Structures of these 8 compounds were characterized by 1H-NMR, 13C-NMR, and high-resolution mass spectrometer (HRMS). The cytotoxicity and preliminary synergistic effects of these 8 compounds were detected against nasopharyngeal carcinoma (NPC) cells and cisplatin-resistant NPC cells (CNE2/CDDP), respectively. Furthermore, the in vivo and in vitro tumor resistance reversal effects of compound 3f were evaluated. Moreover, docking studies were performed in Bclw (2Y6W). The results displayed that compound 3f showed synergistic inhibitory effects with cisplatin against CNE2/CDDP cells proliferation via apoptosis induction. Docking results revealed that compound 3f may exert its effects via inhibiting anti-apoptosis protein Bcl-w. 相似文献
956.
Pairing-deformation-frequency self-consistent crankingWoods-Saxon model is employed to investigate the triaxiality in the ground states of the neutron-rich even-even Mo, Ru isotopes. Deformation evolutions and transition probabilities have been studied, giving the triaxial shapes in their ground states. The kinematic moments of inertia have been calculated to illustrate the gradually rigid deformation. To understand the origin of the asymmetry shape in this region, we analyze the evolution of single-particle orbits with changing γ deformation. The present calculations reveal the importance of the triaxial deformation in describing not only static property, but also rotational behaviors in this mass region, providing significant probes into the shell structure around. 相似文献
957.
Tvaskis V Christy ME Arrington J Asaturyan R Baker OK Blok HP Bosted P Boswell M Bruell A Cochran A Cole L Crowder J Dunne J Ent R Fenker HC Filippone BW Garrow K Gasparian A Gomez J Jackson HE Keppel CE Kinney E Lapikás L Liang Y Lorenzon W Lung A Mack DJ Martin JW McIlhany K Meekins D Milner RG Mitchell JH Mkrtchyan H Moreland B Nazaryan V Niculescu I Opper A Piercey RB Potterveld DH Rose B Sato Y Seo W Smith G Spurlock K van der Steenhoven G Stepanyan S Tadevosian V Uzzle A Vulcan WF Wood SA 《Physical review letters》2007,98(14):142301
We report on a study of the longitudinal to transverse cross section ratio, R=sigmaL/sigmaT, at low values of x and Q2, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Laboratory Hall C spanning the four-momentum transfer range 0.06相似文献
958.
We have performed first-principles calculations using full-potential augmented-plane-wave method to investigate the fundamental properties of the Cd1–xZnxTe alloys. The composition dependence of the lattice constant and the bulk modulus have been estimated from total energy calculations. By means of the analytical fitting the band structures in the vicinity of the Brillouin center a complete set of effective electron- and hole-masses have also been derived. In order to further understand the effects of the chemical bonding on the above macroscopic properties we then studied the relaxation behaviors and the changes of the electronic states upon alloying for x=0.25 system. The results presented here yield a general understanding of the fundamental properties for the Cd1–xZnxTe crystals studies. 相似文献
959.
"使用Brenner-LJ拟合势描述了金刚石与C36团簇原子间的相互作用,并用分子动力学模拟的方法研究单个C36(D6h)在金刚石(100)晶面的沉积机制.通过仿真实验分析了C36团簇的入射能量、入射点位置、入射姿势、入射角度等因素对其成核初期化学吸附过程以及沉积后其稳定性的影响.研究发现:由于C36入射点位置及入射姿势的不同,其在金刚石(100)晶面沉积时的沉积阈值最小值为20 eV,最大值为60 eV;在入射角不超过60o斜射时,由于水平运动分量的存在,C36可能翻滚及平滑至成键能量较小的区域后再成键 相似文献
960.
Haigang Li JingJing Huo Dan Sun Yong Guo Liang Jiang Haijuan Zhang Xiaowei Shi Zhilong Zhao Jinchuan Zhou Chunlan Hu Chun Zhang 《Electrophoresis》2021,42(6):693-699
Polyethylene glycol-modified canine uricase (PEG-UHC) was prepared by modifying the ε-amino group of lysine residues on the canine uricase (UHC) protein to near-saturation with 5 kDa monomethoxyl-polyethylene glycol succinimide (mPEG-SPA-5k). In order to accurately determine the PEGylation uniformity of PEG-UHC, CZE, 3–8% gradient gel SDS-PAGE, and imaging CIEF (iCIEF) analyses were compared. CZE could not effectively separate PEG-UHC proteins with different degrees of modification, 3–8% gradient gel SDS-PAGE could separate PEG-UHC into seven gel bands; however, most of the gel bands were smeared or blurred, and the separation of PEG-UHC samples by iCIEF was significantly better than that by 3–8% gradient gel SDS-PAGE. Under denatured conditions, iCIEF separated 12 pI peaks, and could also accurately quantify the relative monomer PEG-UHC content. More than 85% of the total monomeric PEG-UHC was conjugated with 7–12 PEG molecules; of this 85%, approximately 40% was conjugated with 9–10 PEG molecules. These results demonstrated that iCIEF exhibits good potential for determining the PEGylation homogeneity of PEGylated protein drugs. 相似文献