Screening anti‐tumor compounds from Ligusticum wallichii using cell membrane chromatography combined with high‐performance liquid chromatography and mass spectrometry

Tyrosine 367 Cysteine‐fibroblast growth factor receptor 4 cell membrane chromatography combined with high‐performance liquid chromatography and mass spectrometry was developed. Tyrosine 367 Cysteine‐HEK293 cells were used as the cell membrane stationary phase. The specificity and reproducibility of the cell membrane chromatography was evaluated using 1‐tert‐butyl‐3‐{2‐[4‐(diethylamino)butylamino]‐6‐(3,5‐dimethoxyphenyl)pyrido[2,3‐d]pyrimidin‐7‐yl}urea, nimodipine and dexamethasone acetate. Then, anti‐tumor components acting on Tyrosine 367 Cysteine‐fibroblast growth factor receptor 4 were screened and identified from extracts of Ligusticum wallichii. Components from the extract were retained on the cell membrane chromatographic column. The retained fraction was directly eluted into high‐performance liquid chromatography with mass spectrometry system for separation and identification. Finally, Levistolide A was identified as an active component from Ligusticum wallichii extracts. The 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐tetrazolium bromide‐formazan colorimetric assay revealed that Levistolide A inhibits proliferation of overexpressing the mutated receptor cells with dose‐dependent manner. Phosphorylation of fibroblast growth factor receptor 4 was also decrease under Levistolide A treatment. Flex dock simulation verified that Levistolide A could bind with the tyrosine kinase domain of fibroblast growth factor receptor 4. Therefore, Levistolide A screened by the cell membrane chromatography combined with high‐performance liquid chromatography and mass spectrometry can arrest cell growth. In conclusion, the two‐dimensional high‐performance liquid chromatography method can screen and identify potential anti‐tumor ingredients that specifically act on the tyrosine kinase domain of the mutated fibroblast growth factor receptor 4.     

Decoquinate derivatives: A new class of potent antischistosomal agents against Schistosoma japonicum

Decoquinate (1), an old and inexpensive coccidiostat, exhibited potent antimalarial activity, however, its antischistosomal activity against Schistosoma japonicum has not yet been evaluated. Based on decoquinate, a series of decoquinate derivatives was designed, synthesized, evaluated as a new class of antischistosomal agents against S. japonicum adult worms in vitro. Among them, compound 15 killed 100% of adult S. japonicum in 72 h at the concentration of 10 μmol/L in vitro, exhibited stronger wormkilling activity than PZQ in vitro and could serve as a promising lead compound to develop new antischistosomal agents.     

原子荧光光谱法测定粗锌中的砷

建立了测定粗锌中砷含量的原子荧光光谱法。粗锌样品经硝酸溶液(1+1)低温溶解完全以后,在盐酸介质中,用抗坏血酸预还原,以硫脲掩蔽铜、铁、银等杂质元素,砷被硼氢化钾还原为氢化物,用氩气导入原子化器测量。砷测定结果的相对标准偏差为1.5%~3.0%(n=11),加标回收率为98.4%~103.6%。与国家标准测定方法分光光度法测定结果对比,相对偏差为0.1%~2.4%。该法准确、可靠,适用于砷含量在0.005 0%~0.50%之间的粗锌中砷的测定。     

Ionic liquid functionalized graphene oxide for enhancement of styrene‐butadiene rubber nanocomposites

Ionic liquid 1‐allyl‐3‐methyl‐imidazolium chloride (AMICl) is used to fine‐tune the surface properties of graphene oxide (GO) sheets for fabricating ionic liquid functionalized GO (GO‐IL)/styrene‐butadiene rubber (SBR) nanocomposites. The morphology and structure of GO‐IL are characterized using atomic force microscope, X‐ray diffraction, differential scanning calorimetry, X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, UV‐vis spectra and Raman spectra. The interaction between GO and AMICl molecules as well as the effects of GO‐IL on the mechanical properties, thermal conductivity and solvent resistance of SBR are thoroughly studied. It is found that AMICl molecules can interact with GO via the combination of hydrogen bond and cation–π interaction. GO‐IL can be well‐dispersed in the SBR matrix, as confirmed by X‐ray diffraction and scanning electron microscope. Therefore, the SBR nanocomposites incorporating GO‐IL exhibit greatly enhanced performance. The tensile strength, tear strength, thermal conductivity and solvent resistance of GO‐IL/SBR nanocomposite with 5 parts per hundred rubber GO‐IL are increased by 505, 362, 34 and 31%, respectively, compared with neat SBR. This method provides a new insight into the fabrication of multifunctional GO‐based rubber composites. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis and properties of novel stilbene-twelve alkyl quaternary ammonium salts as antibacterial optical whitening agents

Four novel stilbene-twelve alkyl quaternary ammonium salts 5a–d were synthesized. All synthesized compounds were characterized by FT-IR, ¹H-NMR and elemental analysis. Compounds 5a–d showed efficient whitening effect on cotton fiber and high fastness. Furthermore, compound 5c showed better stability to light than C186 in aqueous solution. The preliminary biological experiment demonstrated compounds 5a–d possessed significant antibacterial activities. Among them, compound 5d turned out to be the most active compound against Candida albicans with MIC₅₀ 4 μg/mL as well as E. coli with MIC₅₀ 16 μg/mL.     

卟啉共价有机框架化合物的研究进展

共价有机框架化合物(COFs)是一类新兴的具有多孔结构的晶态有机聚合物,在储存与分离、催化、能量转化等领域具有广泛应用。本文介绍了一类基于卟啉单元的COFs,从框架构筑及应用开发两方面综述了这类材料的研究进展。     

Synthesis and immunological study of a wall teichoic acid-based vaccine against E. faecium U0317

ABSTRACT

A repeat unit of cell wall teichoic acids (WTA) isolated from E. faecium U0317 was chemically synthesized efficiently by a stepwise strategy. It was derivatized with a 5-aminopentanyl linker to facilitate conjugation with carrier proteins KLH and HSA. Immunological studies of the KLH conjugate 1 demonstrated that it could provoke robust immune responses and high titers of IgG antibodies, which could successfully recognize the synthesized WTA repeat unit 3. This result suggested that synthetic glycoconjugate 1 could be a promising vaccine candidate against E. faecium for further studies.     

a-二芳甲基-b-羰基硫代羧酸酯与肼的环合反应：官能化含5-羟基吡唑基的三芳基甲烷类化合物的合成

本文研究了合成官能化含5-羟基吡唑基的三芳基甲烷类化合物的a-二芳甲基-b-羰基硫代羧酸酯与肼的环合反应。研究表明,在乙醇介质中,回流条件下, a-二芳甲基-b-羰基硫代羧酸酯与肼能有效进行环合反应,高产率制得5-羟基吡唑基三芳甲烷类化合物。该反应条件温和,产率高,操作简单。     

Enhancement of SrTiO<Subscript>3</Subscript>/BiPO<Subscript>4</Subscript> heterostructure for simulated organic wastewater degradation under UV light irradiation

A novel SrTiO₃/BiPO₄ heterostructure with different amounts of SrTiO₃ have been successfully prepared through the hydrothermal process. The photocatalysts were characterized by X-ray powder diffraction, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The photocatalytic performance was evaluated by degrading the methylene blue dye solution under UV light. Results showed that the samples displayed excellent photocatalytic degradation efficiency due to the highly efficient suppression of the recombination of electron–hole pairs. A possible mechanism of SrTiO₃/BiPO₄ heterojunctions was discussed. The research indicated that the as-prepared SrTiO₃/BiPO₄ heterogeneous photocatalyst can be used as an effective material for degrading industrial organic wastewater.