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排序方式: 共有1302条查询结果,搜索用时 31 毫秒
51.
Dr. Sumith A. Kularatne Vishal Deshmukh Dr. Marco Gymnopoulos Dr. Sandra L. Biroc Dr. Jinming Xia Shailaja Srinagesh Dr. Ying Sun Dr. Ning Zou Dr. Mark Shimazu Dr. Jason Pinkstaff Dr. Semsi Ensari Nick Knudsen Anthony Manibusan Dr. Jun Y. Axup Dr. Chan Hyuk Kim Prof. Vaughn V. Smider Dr. Tsotne Javahishvili Prof.Dr. Peter G. Schultz 《Angewandte Chemie (International ed. in English)》2013,52(46):12101-12104
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Compound 1 bearing urea and viologen groups has been designed and synthesized.It could be used as a colorimetric receptor for dicarboxylate anions due to the significant color changes of the solution upon the addition of dicarboxylates.More importantly,the color changes were related to the chain lengths of the dicarboxylates tested.UV-vis,’H NMR and HRMS studies demonstrated that receptor 1 utilized hydrogen bonds and electrostatic interactions to form 1:1 stoichiometry complexes with these anions.In addition,the generation of cation radical 1’ during the complexation process was also detected by EPR. 相似文献
54.
Screening and identification of Caulis Sinomenii bioactive ingredients with dual‐target NF‐κB inhibition and β2‐AR agonizing activities
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Dan Sun Yanqi Han Weiya Wang Zengyong Wang Xiaoyao Ma Yuanyuan Hou Gang Bai 《Biomedical chromatography : BMC》2016,30(11):1843-1853
Caulis Sinomenii (CS) is a valuable traditional medicine in China. Its extract can act as an anti‐inflammatory agent and a vascular smooth muscle relaxant. However, the underlying mechanisms remain unknown. In this study, we developed a simple dual‐target method based on ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry combined with a dual‐target bioactive screening assay for anti‐inflammatory and antispasmodic activities to characterize the chemical structure of various bioactive compounds of CS rapidly. Seven potential NF‐κB inhibitors were identified, including laudanosoline‐1‐O‐xylopyranose, 6‐O‐methyl‐laudanosoline‐1‐O‐glucopyranoside, menisperine, sinomenine, laurifoline, magnoflorine and norsinoacutin. Furthermore, IL‐6 and IL‐8 assays confirmed the anti‐inflammatory effects of these potential NF‐κB inhibitors, in which laudanosoline‐1‐O‐d ‐xylopyranose and menisperine were revealed as novel NF‐κB inhibitors. Among the seven identified alkaloids, three potential β2‐adrenergic receptor agonists, including sinomenine, magnoflorine and laurifoline, were characterized using a luciferase reporter system to measure for the activity of β2‐adrenergic receptor agonists. Finally, sinomenine, magnoflorine and laurifoline were identified not only as potential NF‐κB inhibitors but also as potential β2‐adrenegic receptor agonists, which is the first time this has been reported. Molecular dynamic simulation and docking results suggest that the three dual‐bioactive constituents could not only inhibit Pseudomonas aeruginosa PAK strain‐induced inflammatory responses via a negative regulation of the Braf protein that participates in MAPK signaling pathway but also activate the β2‐adrenegic receptor. These results suggest that CS extract has dual signaling activities with potential clinical application as a novel drug for asthma. 相似文献
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Yanni Lv Xianpeng Shi Jia Fu Qianqian Jia Yuanyuan Lin Hongying Wang Xin Yang Shengli Han 《Biomedical chromatography : BMC》2019,33(9)
Marsdenia tenacissima, or Tongguanteng in Chinese, is a traditional Chinese herb and has a broad application in clinical practice for its pharmacological effects of treating asthma, pneumonia, tonsillitis, pharyngitis tumors, etc. However, few studies have reported the screening of the active components of this medicine for tumor therapy. In this work, a two‐dimensional analytical system was developed to screen antagonists of epidermal growth factor receptor (EGFR) from M. tenacissima. A fraction was retained on the EGFR cell membrane chromatography (CMC) column, separated and identified as tenacissoside G (TG), tenacissoside H (TH) and tenacissoside I (TI) by two‐dimensional HPLC–IT–TOF–MS. Molecular docking and 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2‐H‐tetrazolium bromide (MTT) assay were carried out to assess the activity of TS (including TG, TH and TI). Molecular docking results showed that the binding mode of TS on EGFR is similar to that of gefitinib. The MTT assay demonstrated that gefitinib and TS (especially TI) could inhibit the growth of EGFR highly expressed cell lines in a dose‐dependent manner in the range of 5–50 μmol/L. In conclusion, the two‐dimensional EGFR/CMC–HPLC–IT–TOF–MS system could be a useful approach in drug discovery from traditional Chinese medicines for searching for potential antitumor candidates. 相似文献
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Nadezhda S. Temnyakova Dmitry A. Vasilenko Mstislav I. Lavrov Dmitry S. Karlov Yuri K. Grishin Vladimir L. Zamoyski Vladimir V. Grigoriev Elena B. Averina Vladimir A. Palyulin 《Mendeleev Communications》2021,31(2):219-220
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Milan Jakubek Zdeněk Kejík Robert Kaplánek Hana Veselá David Sýkora Pavel Martásek 《Supramolecular chemistry》2018,30(3):218-226
Perimidine-based chelators 1 and 2 were prepared, and their structures were confirmed by 1H and 13C NMR, MS spectroscopy and elemental analysis. These compounds were studied as specific synthetic receptors for the recognition of transition metal ions. They exhibited high affinity and selectivity towards Cu(II) ions. The conditional binding constants, linear dynamic range and detection limit were determined by UV–vis spectroscopy. These parameters demonstrated high potential of the prepared synthetic receptors for the recognition and determination of Cu(II) ions. The minimum detectable concentrations of Cu(II) ions for the synthetic receptors 1 and 2 were 270 and 75 nM (R 2 = 0.9915 and 0.9964) in aqueous medium (water/DMSO; 99:1 (v/v)), respectively. 相似文献
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Shin-ichi Kondo Kimihiro Endo Jun Iioka Keisuke Sato Yuka Matsuta 《Tetrahedron letters》2017,58(43):4115-4118
We have successfully prepared 5-(2-phenylethynyl)isophathalilc acid as a signaling unit and the corresponding derivatives for an anion receptor 2 and a barbiturate receptor 4. Receptor 2 showed characteristic UV–vis changes and dramatic fluorescence quenching upon the addition of anions and receptor 4 showed UV–vis and an OFF-ON fluorescence changes upon the addition of dibutylbarbituric acid based on the diphenylethyne moiety. 相似文献
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目的 观察淋巴管透明质酸受体1(LYVE-1)的表达和癌周组织中淋巴管的生成情况在甲状腺恶性肿瘤的变化及转
移中的作用。方法 应用免疫组织化学和real-time PCR方法检测45 例甲状腺乳头状癌中央区、癌周边区和正常甲状腺组织中的LYVE-1及其mRNA 表达情况,并计算淋巴管密度(LVD)。结果 甲状腺乳头状癌周边区LVD 高于甲状腺乳头状癌中央区,而正常组织中很少见LYVE-1 阳性的微淋巴管;甲状腺乳头状癌周边区LVD 与淋巴结转移有密切关系(P<0.05)。结论 LYVE-1是一种特异性较高的淋巴管内皮特异性标志物,对淋巴管生成促进甲状腺乳头状癌的淋巴结转移。 相似文献