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Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/β-catenin axis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第11期13卷 867-874页

作者： xiao-hua xu Yi-chao GAN Gen-bo xu Ting CHEN Hong ZHOU Jin-fen TANG Ying GU Fei xu Ying-ying XIE xiao-ying ZHAO Rong-zhen xu Department of Hematology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Department of Cancer Institute the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

Objective:To evaluate the effects of tetrandrine citrate, a novel tetrandrine salt with high water solubility, on the growth of imatinib (IM)-resistant chronic myeloid leukemia (CML) in vitro and in vivo, and reveal action molecular mechanisms. Methods:Cell viability in vitro was measured using methyl thiazolyl tetrazolium (MTT) assay. CML cell growth in vivo was assessed using a xenograft model in nude mice. Bcr-Abl and β-catenin protein levels were determined using Western blotting. Bcr-Abl messenger RNA (mRNA) was measured by reverse transcription polymerase chain reaction (RT-PCR). Flow cytometry (FCM) was used to determine cell cycle status. Results:Tetrandrine citrate inhibited the growth of IM-resistant K562 cells, primary leukemia cells, and primitive CD34 + leukemia cells, and their inhibition concentration that inhibited 50% of target cells (IC 50 ) ranged from 1.20 to 2.97 μg/ml. In contrast, tetrandrine citrate did not affect normal blood cells under the same conditions, and IC 50 values were about 10.12-13.11 μg/ml. Oral administration of tetrandrine citrate caused complete regression of IM-resistant K562 xeno-grafts in nude mice without overt toxicity. Western blot results revealed that treatment of IM-resistant K562 cells with tetrandrine citrate resulted in a significant decrease of both p210 Bcr-Abl and β-catenin proteins, but IM did not affect the Bcr-Abl protein levels. Proteasome inhibitor, MG132, did not prevent tetrandrine-mediated decrease of the p210 Bcr-Abl protein. RT-PCR results showed that tetrandrine treatment caused a decrease of Bcr-Abl mRNA. FCM analysis indicated that tetrandrine induced gap 1 (G 1 ) arrest in CML cells. Conclusions:Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and CML cells. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210 Bcr-Abl mRNA and β-catenin protein.

关键词： Chronic myeloid leukemia Imatinib-resistance Tetrandrine citrate Bcr-Abl protein β-catenin protein

Oxidation behavior of in-situ Al_2O_3/TiAl composites at 900°C in static air

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 339-344页

作者： Tao-tao Ai fen Wang xiao-ming feng Department of Materials Science and Engineering Shaanxi University of Technology Hanzhong 723003 China School of Materials Science and Engineering Shaanxi University of Science and Technology Xi＇an 710021 China

In-situ Al2O3/TiAl composites were successfully synthesized from the starting powders of Ti, Al, TiO2 and Nb2O5. The oxidation behavior of the composites at 900℃ in static air was investigated. The results indicate that the composite samples present a much lower oxidation mass gain. Under long-time intensive oxidation exposure, the formed oxide scale is multi-layer. The formation of the outer TiO2 layer is fine and dense, the internal Al2O3 scale has good adhesiveness with the outer TiO2 scale, and the TiO2＋Al2O3 mixed layer forming the protective oxide scale is favorable for the improvement of oxidation resistance. It is believed that the incorporation of Al2O3 particulates into the metal matrix decreases the coefficient of thermal expansion of the substrate, and forms a local three-dimensional network structure that can hold the oxide scale. The formation of the oxide scale with finer particle size, stronger adherence, less micro-defects and slower growth rate can contribute to the improvement of oxidation resistance. Nb element plays an important role in reducing the internal oxidation action of the materials, restraining the growth of TiO2 crystals and promoting the stable formation of the Al2O3-riched layer, which is beneficial to improve the oxidation properties.

关键词： intermetallic matrix composites alumina oxidation resistance scale spallation high temperature

Molecular Mechanisms and Genetic Basis of Heavy Metal Tolerance/ Hyperaccumulation in Plants

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Journal of Integrative Plant Biology 2005年第9期47卷 1025-1035页

作者： xiao-EYANG xiao-fen JIN Ying fenG Ejazul ISLAM Key Laboratory of Environmental Remediation and Ecosystem Health of Ministry of Education College of Natural Resources and Environmental Sciences Zhejiang University Hangzhou 310029 China

Phytoremediation has gained increased attention as a cost-effective method for the remediation of heavy metal-contaminated sites. Because some plants possess a range of potential mechanisms that may be involved in the detoxification of heavy metals, they manage to survive under metal stresses. High tolerance to heavy metal toxicity could rely either on reduced uptake or increased plant internal sequestration, which is manifested by an interaction between a genotype and its environment. The growing application of molecular genetic technologies has led to increased understanding of mechanisms of heavy metal tolerance/accumulation in plants and, subsequently, many transgenic plants with increased heavy metal resistance, as well as increased uptake of heavy metals, have been developed for the purpose of phytoremediation. In the present review, our major objective is to concisely evaluate the progress made so far in understanding the molecular/cellular mechanisms and genetic basis that control the uptake and detoxification of metals by plants.

关键词： amino acids heat shock proteins metal-binding proteins metal transporters metallothioneins organic acids phytochelatins phytoremediation.

Surface Polarization Effects on Collapse Transition of Polyelectrolyte Brushes

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Chinese Journal of Polymer Science 2024年第9期42卷 1313-1320,I0006页

作者： xiao-Fei xu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai200237China

Polyelectrolyte brushes(PEBs)are commonly used to modify surface that have attracted great research *** dielectric permittivity of the grafted surface is typically significantly different from that of solution,which results in surface polarization(SP)effect with a jump of electric *** is thus important to study how SP alters the PEB’s structure and *** this work,the SP effects on PEB structure was studied using a statistical thermodynamic *** free energy functional to describe SP effect was constructed by using the image-charge ***,the electrostatic potential was solved from a modified Poisson-Boltzmann equation taking the ion solvation effect into *** the absence of SP,the thickness of PEB exhibited a continuous collapse transition when decreasing the solvent *** the presence of SP,the collapse became a jump-like *** energy analysis showed that the long-range Coulombic interaction dominated the transition because of the enhanced counterion condensation in the presence of *** theory provides an effective tool to study SP effect on PEBs,and the results explain the underlying physics in PEB collapse transition.

关键词： Surface polarization Polyelectrolyte brush Image charge Ion solvation Polyelectrolyte collapse transition

Synergistic effects of dodecane-castor oil acid mixture on the flotation responses of low-rank coal:A combined simulation and experimental study

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International Journal of Mining Science and Technology 2023年第5期33卷 649-658页

作者： fen xu Shiwei Wang Rongjie Kong Chengyong Wang College of Environmental and Chemical Engineering Dalian UniversityDalian 116622China School of Mines and Mechanical Engineering Liupanshui Normal UniversityLiupanshui 553004China

The utilization of an appropriate collector or surfactant is crucial for the beneficiation of low-rank ***,in previous studies,the selection of surfactants was primarily based on flotation procedures,which hinders the understanding of the interaction mechanism between surfactant groups and oxygen-containing functional groups at the surface of low-rank *** this study,we investigate the flotation of low-rank coal in the presence of a composite collector by using a combined theoretical and experimental *** maximum flotation mass recovery achieved was 82.89%using a 3:1 mixture of dodecane and castor oil ***-transform infrared and X-ray photoelectron spectroscopic analyses showed that castor oil acid was effectively adsorbed onto the surface of low-rank coal,enhancing the hydrophobicity of the *** addition,the diffusion coefficient of water molecules in the water-composite collector-coal system was greater than that in the dodecane ***,due to the presence of castor oil acid in the flotation process,the adsorption distance of dodecane and low-rank coal became *** dynamics simulations revealed that the diffusion and interaction of surfactant molecules at the interface of low-rank coal particles and water was enhanced because the adsorption of the dodecane-castor oil acid mixture is primarily controlled by hydrogen bonds and electrostatic *** on these results,a better surfactant for flotation of low-rank coal is also proposed.

关键词： Low-rank coal Flotation Castor oil acid Surface hydrophobicity Molecular dynamics simulation

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第1期 257-263页

作者： Jiapian Huang Chenxin Wang xu Wang xiaoyu Zhou Wei xiao Jie Wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

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Design and Properties of Fluoroelastomer Composites via Incorporation of MWCNTs with Varied Modification

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Chinese Journal of Polymer Science 2020年第9期38卷 983-992,I0007页

作者： Guang-Yao Yang Li-fen Tong xiao-Bo Liu Research Branch of Advanced Functional Materials School of Materials and EnergyUniversity of Electronic Science and Technology of ChinaChengdu 610054China

Multi-walled carbon nanotubes(MWCNTs)modified with silane coupling agent A-1120(MWCNTs-A1120)were *** with the raw MWCNTs,acidified MWCNTs(MWCNTs-COOH),and MWCNTs grafted with EDA(MWCNTs-NH2),MWCNTs-A1120 have the best dispersion in fluoroelastomer at the same doping ***,fluoroelastomer/MWCNTs-A1120 composite has the best mechanical properties with tensile strength of 13.92 MPa and elongation at break of 111.78%.Then,the effects of doping amount of MWCNTs-A1120 on the electrical properties of the composites were *** dielectric constant of the composite increases with the increase of MWCNTs-A1120,and the dielectric loss does not change much at the low doping amount such as 0.5 wt%.When the doping amount of MWCNTs-A1120 is 5 wt%,the dielectric constant and the dielectric loss value are greatly increased,and the volume resistivity is greatly decreased,which proves that the conductive network is formed in the composite,so the filling amount of 5 wt%is the percolation *** tensile deformation of the sample also affects the electrical properties of the *** the tensile deformation increases,the dielectric constant and dielectric loss of the composite *** the composite with 5 wt%MWCNTs-A1120,excessive tensile deformation will destroy the conductive network structure of the composite,so the composite will change from conductive material to dielectric ***,such composite is a good candidate for flexible conductive material or flexible dielectric material used in harsh environments such as high temperatures and various aggressive solvents.

关键词： Modified-MWCNTs Fluoroelastomer nanocomposite Interface compatibility Dielectric properties Volume resistivity

Graphene-based materials for polymer solar cells

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Chinese Chemical Letters 2016年第8期27卷 1259-1270,1468页

作者： xiao-feng Lin Zi-Yan Zhang Zhong-Ke Yuan Jing Li xiao-fen xiao Wei Hong xu-Dong Chen Ding-Shan Yu Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education of China School of Chemistry and Chemical EngineeringSun Yat-sen University Key Laboratory of High Performance Polymer-based Composites of Guangdong Province School of Chemistry and Chemical Engineering Sun Yat-sen University

Due to the remarkable electronic,optical,thermal,and mechanical properties,graphene-based materials have shown great potential in a wide range of technique ***,the high transparency,conductivity,flexibility,and abundance make graphene materials highly attractive for polymer solar cells（PSCs）.Graphene-based materials have been regarded as one promising candidate used in various parts in PSCs not only as electrodes,but also as interfacial layers and active layers with an aim to boost the power conversion efficiency of the *** this review,we summarize the recent progress about the design and synthesis of graphene-based materials for efficient PSCs along with the related challenges and future perspectives.

关键词： Graphene Polymer solar cells Electrodes Interfacial layers Active layers

Application of Chinese milk vetch affects rice yield and soil productivity in a subtropical double-rice cropping system

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Journal of Integrative Agriculture 2020年第8期19卷 2116-2126页

作者： CHEN Jing-rui QIN Wen-jing CHEN xiao-fen CAO Wei-dong QIAN Guo-min LIU Jia xu Chang-xu Institute of Soil&Fertilizer and Resources&Environment Jiangxi Academy of Agricultural SciencesNanchang 330200P.R.China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Dengjiabu Original Rice Breeding Farm Yingtan 335000P.R.China

Green manure can be used as a substitute for chemical fertilizer without reducing rice *** studied the responses of soil fertility and rice yield to different combinations of Chinese milk vetch(CMV;Astragalus sinicus L.)and chemical fertilizer in a subtropical double-rice cropping *** goal is to reduce chemical fertilizer use and decrease environmental *** with the recommended rate of chemical fertilizer(CF),both early-and late-rice yields in the two treatments supplied with 15 and 22.5 Mg CMV ha^-1 plus 60%CF(represented as 60 A and 60 B,respectively)showed no significant differences while the two treatments supplied with 30 and 37.5 Mg CMV ha^-1 plus 60%CF(represented as 60 C and 60 D,respectively)showed significantly higher *** sustainable yield index(SYI)values in the 60 C and 60 D treatments with double-rice croppong system were significantly higher than those in other treatments(P0.05).Therefore,a relatively high Chinese milk vetch incorporation rate(≥30 Mg ha^-1)was more effective in improving the productivity and sustainability of paddy *** decreased coefficients of early-rice yield and the Chinese milk vetch incorporation rate in 2014 implied that the benefits of soil fertility and rice yield created by Chinese milk vetch input

关键词： Chinese milk vetch double-rice cropping system reduced chemical fertilizer sustainability