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961.
Screening anaphylactic components of MaiLuoNing injection by using rat basophilic leukemia‐2H3 cell membrane chromatography coupled with HPLC–ESI‐TOF‐MS 下载免费PDF全文
Shengli Han Yanni Lv Wenjing Xue Jiao Cao Ronghua Cui Tao Zhang 《Journal of separation science》2016,39(3):466-472
MaiLuoNing injection is a traditional Chinese medicine that used clinically since the 1950s in China. However, anaphylactic reactions, through the potentiation of mast cell degranulation, have been reported. In the present study, a rat basophilic leukemia‐2H3 cell membrane chromatography coupled with high‐performance liquid chromatography and electrospray ionization‐ion trap‐time of flight‐mass spectrometry method was established for screening, analyzing, and identifying the potential anaphylactic components of MaiLuoNing injection. Harpagoside, a potential degranulator of rat basophilic leukemia‐2H3 cells, was retained in rat basophilic leukemia‐2H3 cell membrane chromatography. We aimed to evaluate the retained components to determine which of those were capable of inducing degranulation of basophilic leukemia cells. A β‐hexosaminidase assay revealed that harpagoside can induce rat basophilic leukemia‐2H3 cell degranulation in a dose‐dependent manner. BLBA/c mice also exhibit passive cutaneous anaphylaxis in response to harpagoside. These results indicate that rat basophilic leukemia‐2H3 cell membrane chromatography coupled with high‐performance liquid chromatography and electrospray ionization ion trap time‐of‐flight mass spectrometry is effective in screening for the anaphylactic components of MaiLuoNing injection. 相似文献
962.
Solution‐Liquid‐Solid Synthesis of Hexagonal Nickel Selenide Nanowire Arrays with a Nonmetal Catalyst 下载免费PDF全文
Dr. Kun Xu Hui Ding Kaicheng Jia Xiuli Lu Pengzuo Chen Tianpei Zhou Han Cheng Si Liu Prof. Changzheng Wu Prof. Yi Xie 《Angewandte Chemie (International ed. in English)》2016,55(5):1710-1713
Inorganic nanowire arrays hold great promise for next‐generation energy storage and conversion devices. Understanding the growth mechanism of nanowire arrays is of considerable interest for expanding the range of applications. Herein, we report the solution‐liquid‐solid (SLS) synthesis of hexagonal nickel selenide nanowires by using a nonmetal molecular crystal (selenium) as catalyst, which successfully brings SLS into the realm of conventional low‐temperature solution synthesis. As a proof‐of‐concept application, the NiSe nanowire array was used as a catalyst for electrochemical water oxidation. This approach offers a new possibility to design arrays of inorganic nanowires. 相似文献
963.
Prof. Songping Wu Dr. Cuiping Han James Iocozzia Mingjia Lu Rongyun Ge Rui Xu Prof. Zhiqun Lin 《Angewandte Chemie (International ed. in English)》2016,55(28):7898-7922
Germanium‐based nanomaterials have emerged as important candidates for next‐generation energy‐storage devices owing to their unique chemical and physical properties. In this Review, we provide a review of the current state‐of‐the‐art in germanium‐based materials design, synthesis, processing, and application in battery technology. The most recent advances in the area of Ge‐based nanocomposite electrode materials and electrolytes for solid‐state batteries are summarized. The limitations of Ge‐based materials for energy‐storage applications are discussed, and potential research directions are also presented with an emphasis on commercial products and theoretical investigations. 相似文献
964.
Dr. Jong Wook Hong Yena Kim Dae Han Wi Seunghoon Lee Su‐Un Lee Young Wook Lee Prof. Sang‐Il Choi Prof. Sang Woo Han 《Angewandte Chemie (International ed. in English)》2016,55(8):2753-2758
A synthesis strategy for the preparation of ultrathin free‐standing ternary‐alloy nanosheets is reported. Ultrathin Pd‐Pt‐Ag nanosheets with a thickness of approximately 3 nm were successfully prepared by co‐reduction of the metal precursors in an appropriate molar ratio in the presence of CO. Both the presence of CO and the interplay between the constituent metals provide fine control over the anisotropic two‐dimensional growth of the ternary‐alloy nanostructure. The prepared Pd‐Pt‐Ag nanosheets were superior catalysts of ethanol electrooxidation owing to their specific structural and compositional characteristics. This approach will pave the way for the design of multicomponent 2D nanomaterials with unprecedented functions. 相似文献
965.
An Alignment Medium for Measuring Residual Dipolar Couplings in Pure DMSO: Liquid Crystals from Graphene Oxide Grafted with Polymer Brushes 下载免费PDF全文
Wen Zong Gao‐Wei Li Jiang‐Ming Cao Prof. Xinxiang Lei Prof. Mao‐Lin Hu Dr. Han Sun Prof. Christian Griesinger Prof. Ren Xiang Tan 《Angewandte Chemie (International ed. in English)》2016,55(11):3690-3693
Residual dipolar couplings (RDCs) have attracted attention in light of their great impact on the structural elucidation of organic molecules. However, the effectiveness of RDC measurements is limited by the shortage of alignment media compatible with widely used organic solvents, such as DMSO. Herein, we present the first liquid crystal (LC) based alignment medium that is compatible with pure DMSO, thus enabling RDC measurements of polar and intermediate polarity molecules. The liquid crystals were obtained by grafting polymer brushes onto graphene oxide (GO) using free radical polymerization. The resulting new medium offers several advantages, such as absence of background signals, narrow line shapes, and tunable alignment. Importantly, this medium is compatible with π‐conjugated molecules. Moreover, sonication‐induced fragmentation can reduce the size of GO sheets. The resulting anisotropic medium has moderate alignment strength, which is a prerequisite for an accurate RDC measurement. 相似文献
966.
Structure–Activity Studies of Cysteine‐Rich α‐Conotoxins that Inhibit High‐Voltage‐Activated Calcium Channels via GABAB Receptor Activation Reveal a Minimal Functional Motif 下载免费PDF全文
Dr. Bodil B. Carstens Dr. Géza Berecki James T. Daniel Han Siean Lee Kathryn A. V. Jackson Dr. Han‐Shen Tae Dr. Mahsa Sadeghi Dr. Joel Castro Tracy O'Donnell Dr. Annemie Deiteren Prof. Stuart M. Brierley Prof. David J. Craik Prof. David J. Adams Dr. Richard J. Clark 《Angewandte Chemie (International ed. in English)》2016,55(15):4692-4696
α‐Conotoxins are disulfide‐rich peptides that target nicotinic acetylcholine receptors. Recently we identified several α‐conotoxins that also modulate voltage‐gated calcium channels by acting as G protein‐coupled GABAB receptor (GABABR) agonists. These α‐conotoxins are promising drug leads for the treatment of chronic pain. To elucidate the diversity of α‐conotoxins that act through this mechanism, we synthesized and characterized a set of peptides with homology to α‐conotoxins known to inhibit high voltage‐activated calcium channels via GABABR activation. Remarkably, all disulfide isomers of the active α‐conotoxins Pu1.2 and Pn1.2, and the previously studied Vc1.1 showed similar levels of biological activity. Structure determination by NMR spectroscopy helped us identify a simplified biologically active eight residue peptide motif containing a single disulfide bond that is an excellent lead molecule for developing a new generation of analgesic peptide drugs. 相似文献
967.
Dr. Xiaoyu Han Wai‐Lun Chan Dr. Weijun Yao Dr. Yongjiang Wang Prof. Dr. Yixin Lu 《Angewandte Chemie (International ed. in English)》2016,55(22):6492-6496
Phosphine‐catalyzed enantioselective annulation reactions involving ketimines are a daunting synthetic challenge owing to the intrinsic low reactivity of ketimine substrates. A highly enantioselective [3+2] cycloaddition reaction that makes use of isatin‐derived ketimines as reaction partners was developed. Notably, both simple and γ‐substituted allenoates could be utilized, and various 3,2′‐pyrrolidinyl spirooxindoles with a tetrasubstituted stereocenter were obtained in excellent yields and with nearly perfect enantioselectivity (>98 % ee in all cases). 相似文献
968.
Triptycene‐Based Chiral Macrocyclic Hosts for Highly Enantioselective Recognition of Chiral Guests Containing a Trimethylamino Group 下载免费PDF全文
Geng‐Wu Zhang Peng‐Fei Li Zheng Meng Han‐Xiao Wang Ying Han Prof. Chuan‐Feng Chen 《Angewandte Chemie (International ed. in English)》2016,55(17):5304-5308
A new class of chiral macrocyclic arene composed of three chiral 2,6‐dihydroxyltriptycene subunits bridged by methylene groups was designed and synthesized. Structural studies showed that the macrocyclic molecule adopts a hex‐nut‐like structure with a helical chiral cavity and highly fixed conformation. Efficient resolution was achieved through the introduction of chiral auxiliaries to give a couple of enantiopure macrocycles, which exhibited high enantioselectivity towards three pairs of chiral compounds containing a trimethylamino group. 相似文献
969.
Open‐Pore Two‐Dimensional MFI Zeolite Nanosheets for the Fabrication of Hydrocarbon‐Isomer‐Selective Membranes on Porous Polymer Supports 下载免费PDF全文
Han Zhang Prof. Qiang Xiao Prof. Xianghai Guo Prof. Najun Li Prashant Kumar Neel Rangnekar Mi Young Jeon Prof. Shaeel Al‐Thabaiti Prof. Katabathini Narasimharao Prof. Sulaiman Nasir Basahel Prof. Berna Topuz Frank J. Onorato Prof. Christopher W. Macosko Prof. K. Andre Mkhoyan Prof. Michael Tsapatsis 《Angewandte Chemie (International ed. in English)》2016,55(25):7184-7187
Two‐dimensional zeolite nanosheets that do not contain any organic structure‐directing agents were prepared from a multilamellar MFI (ML‐MFI) zeolite. ML‐MFI was first exfoliated by melt compounding and then detemplated by treatment with a mixture of H2SO4 and H2O2 (piranha solution). The obtained OSDA‐free MFI nanosheets disperse well in water and can be used for coating applications. Deposits made on porous polybenzimidazole (PBI) supports by simple filtration of these suspensions exhibit an n‐butane/isobutane selectivity of 5.4, with an n‐butane permeance of 3.5×10?7 mol m?2 s?1 Pa?1 (ca. 1000 GPU). 相似文献
970.
Joshua P. Green Dr. Yang Han Rebecca Kilmurray Prof. Martyn A. McLachlan Prof. Thomas D. Anthopoulos Prof. Martin Heeney 《Angewandte Chemie (International ed. in English)》2016,55(25):7148-7151
Arsole‐containing conjugated polymers are a practically unexplored class of materials despite the high interest in their phosphole analogues. Herein we report the synthesis of the first dithieno[3,2‐b;2′,3′‐d]arsole derivative, and demonstrate that it is stable to ambient oxidation in its +3 oxidation state. A soluble copolymer is obtained by a palladium‐catalyzed Stille polymerization and demonstrated to be a p‐type semiconductor with promising hole mobility, which was evaluated by field‐effect transistor measurements. 相似文献