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Syntheses of amphiphilic biodegradable copolymers of poly(ethyl ethylene phosphate) and poly(3-hydroxybutyrate) for drug delivery

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science china Chemistry 2009年第7期52卷 961-968页

作者： CHENG Jing1 & WANG Jun2 1 Department of Polymer science and Engineering, university of science and technology of china, hefei 230026, china 2 hefei national laboratory for physical sciences at microscale, school of life sciences, university of science and technology of china, hefei 230027, china Department of Polymer science and Engineering University of Science and Technology of China Hefei China hefei national laboratory for physical sciences at microscale School of Life Sciences University of Science and Technology of China Hefei China

Biodegradable and amphiphilic triblock copolymers poly(ethyl ethylene phosphate)-poly(3-hydroxybutyrate)-poly(ethyl ethylene phosphate) (PEEP-b-PHB-b-PEEP) have been successfully synthesized through ring-opening polymerization. The structures are confirmed by gel permeation chromatography and NMR analyses. Crystallization investigated by X-ray diffraction reveals that the block copolymer with higher content of poly(ethyl ethylene phosphate) (PEEP) is more amorphous, showing decreased crystallizability. The obtained copolymers self-assemble into biodegradable nanoparticles with a coreshell micellar structure in aqueous solution, verified by the probe-based fluorescence measurements and transmission electronic microscopy (TEM) observation. The hydrophobic poly(3-hydroxybutyrate) (PHB) block serves as the core of the micelles and the micelles are stabilized by the hydrophilic PEEP block. The size and size distribution are related to the compositions of the copolymers. Paclitaxel (PTX) has been encapsulated into the micelles as a model drug and a sustained drug release from the micelles is observed. MTT assay also demonstrates that the block copolymers are biocompatible, rendering these copolymers attractive for drug delivery.

关键词： poly(3-hydroxybutyrate) polyphosphoester drug delivery polymeric nanoparticles

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Bcl-2 cleavages at two adjacent sites by different caspases promote cisplatin-induced apoptosis

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Cell Research 2007年第5期17卷 441-448页

作者： Jianbei Zhu1 Ying Yang1 Jiarui Wu1,2 1 Kev laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, 320 Yueyang Road, Shanghai 200031, china 2 hefei national laboratory for physical sciences at microscale and school of life sciences, university of science & technology of china, hefei 230027, china Key laboratory of Systems Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China hefei national laboratory for physical sciences at microscale and school of life sciences University of Science & Technology of China Hefei China

The protein encoded by bcl-2 proto-oncogene plays an important role in the mitochondria-mediated apoptotic *** the general role of Bcl-2 is anti-apoptotic, previous work showed that Bcl-2 fragments cleaved by caspasescould promote apoptotic process. We report herein that Bcl-2 protein was cleaved to produce two fragments of around23 kDa in human hepatocarcinoma BEL-7404 cells or in Bcl-2 overexpressing CHO cells induced by cisplatin. Treat-ing cells with the general caspase inhibitor z-VAD-fmk blocked the induced cleavage of Bcl-2. Mutagenesis analysesshowed that Bcl-2 was cleaved by caspases at two adjacent recognition sites in the loop domain (YEWD31↓AGD34↓V),which could be inhibited by caspase-8 and -3 inhibitors, respectively. Overexpression of the carboxyl terminal 23 kDafragments increased the sensitivity of CHO cells to cisplatin-induced apoptosis. These results indicate that Bcl-2 can becleaved into two close fragments by different caspases during cisplatin-induced apoptosis, both of which contribute tothe acceleration of apoptotic process.

关键词： Bcl-2 apoptosis cisplatin caspase-3 caspase-8

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Scheme for Entanglement Concentration of Unknown Multiparticle Greenberger-Horne-Zeilinger or W Class States

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Communications in Theoretical Physics 2007年第12期48卷 1025-1028页

作者： SONG Wei hefei national laboratory for physical sciences at microscale and Department of Modern Physics,university of science and technology of china,hefei 230026,china hefei national laboratory for physical sciences at microscale and Department of Modern Physics University of Science and Technology of China Hefei 230026 China

We present,two schemes for concentrating unknown nonmaximally entangled Greenberger Horme-Zeilinger(GHZ) or W class *** first scheme for concentrating the nonmaximally entangled GHZ state is based on linearoptical *** second scheme for concentrating the W class states can be applied to a wide variety of atomic *** of our schemes are not postselection ones and are within the current technologies.

关键词： entanglement concentration GHZ class states W class states

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p53 and Bad: remote strangers become close friends

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Cell Research 2007年第4期17卷 283-285页

作者： Peng Jiang~1 Wenjing Du~1 Mian Wu ~1hefei national laboratory for physical sciences at microscale and school of life sciences,university of science and technology of china,Anhui 230027,china hefei national laboratory for physical sciences at microscale and school of life sciences University of Science and Technology of China Anhui 230027 China

The transcription factor p53 is a key regulator of theDNA damage response to genotoxic stress in higher ***/inactivation of p53 has been implicatedin the pathogenesis of many tumor types[1].p53 respondsto cellular insults,such as DNA damage or hypoxia,eitherby arresting the cell cycle so that DNA damage could berepaired,or by triggering apoptosis if DNA repair is *** activation of apoptosis-related genes byp53 is critical for the induction of programmed cell *** search of target genes of p53 involved in cell-cyclearrest and/or apoptosis,numerous p53-inducible geneshave been identified over the past 15 *** themare genes such as Bax[2],Puma[3],Noxa[4],Bid [5],p21waf1[6],and many *** apoptosis-relatedfactors function in different cell organelles including thecytosolic membrane,the mitochondria and the ***,none of these candidate effectors alone can beaccountable for the complicated mechanisms underlyingthe p53 transcription-dependent apoptotic signaling *** work implicated that Bad may contributeto p53-induced mitochondria-mediated apoptosis,yet noknown molecular mechanism had been ascribed to this

关键词： p53 and Bad gene remote strangers become close friends

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Facile synthesis of dendrimer-like star-branched poly(isopropylacrylamide) via combination of click chemistry and atom transfer radical polymerization

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science china Chemistry 2010年第12期53卷 2520-2527页

作者： WAN XueJuan,XU Jian & LIU ShiYong CAS Key laboratory of Soft Matter Chemistry Department of Polymer science and Engineering,hefei national laboratory for physical sciences at the microscale,university of science and technology of china,hefei 230026,china CAS Key laboratory of Soft Matter Chemistry Department of Polymer science and Engineering Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei China

We report a facile synthesis method of dendrimer-like star-branched poly(N-isopropylacrylamide) (PNIPAM) via the combination of click chemistry and atom transfer radical polymerization (ATRP) by employing the arm-first ***,the α-azido-ω-chloro-heterodifunctionalized building block,N3-PNIPAM-Cl (G0-Cl),was synthesized via ATRP by 3-azidopropyl 2-chloropropionate as the *** advantage of click chemistry,the first generation (G1) of dendrimer-like star-branched PNIPAM,G1-(Cl)3,was facilely prepared via the click coupling reaction between G0-Cl and *** the construction of second generation (G2) dendrimer-like star-branched PNIPAM,G2-(Cl)6,terminal chloride moieties of G1-(Cl)3 were first converted to azide,and then reacted with excess tripropargylamine to give G1-(alkynyl)6 ;G2-(Cl)6 was subsequently prepared via click reaction between G1-(alkynyl) 6 and *** permeation chromatography (GPC) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were employed to confirm the successful construction of dendrimer-like star-branched *** unique thermal phase transition behavior of this dendrimer-like star-branched polymer in aqueous solutions was further investigated by turbidimetry and micro-differential scanning calorimetry (Micro-DSC).

关键词： dendrimer-like branched ATRP click chemistry

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Short exposure to paclitaxel induces multipolar spindle formation and aneuploidy through promotion of acentrosomal pole assembly

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science china(life sciences) 2010年第11期53卷 1322-1329页

作者： BIAN MingLei1, FU JingYan1, YAN Yan1, CHEN Qiang1, YANG Chao2, SHI QingHua2,JIANG Qing1 & ZHANG ChuanMao1 1MOE Key laboratory of Cell Proliferation and Differentiation and the State Key laboratory of Bio-membrane and Membrane Bio-engineering, College of life sciences, Peking university, Beijing 100871, china 2hefei national laboratory for physical sciences at microscale and school of life sciences, university of science and technology of china, hefei 230026, china MOE Key laboratory of Cell Proliferation and Differentiation and the State Key laboratory of Bio-membrane and Membrane Bio-engineering College of Life Sciences Peking University Beijing China hefei national laboratory for physical sciences at microscale and school of life sciences University of Science and Technology of China Hefei China

Paclitaxel is a widely used microtubule drug and cancer medicine. Here we report that by short exposure to paclitaxel at a low dose, multipolar spindles were induced in mitotic cells without centrosome amplification. Both TPX2 depletion and Aurora-A overexpression antagonized the multipolarity. Live cell imaging showed that some paclitaxel-treated cells accomplished multipolar cell division and a portion of the daughter cells went on to the next round of mitosis. The surviving cells grew into clones with varied genome content. The results indicated that an aneuploidy population could be induced by short exposure to paclitaxel at a low dose, implicating potential side effects of paclitaxel.

关键词： paclitaxel tpx2 Aurora-A multipolar cell division aneuploidy

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Chronic morphine exposure induces degradation of receptive field properties of LGN cells in cats

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Acta Pharmacologica Sinica 2005年第9期26卷 1034-1038页

作者： Li-hua HE~2 Guang-xing LI~2 Xiang-mi LI~2 Yi-feng ZHOU~(2,3,4)2 hefei national laboratory for physical sciences at microscale and school of life science,university of science and technology of china,hefei 230027,china 3 laboratory of Visual Information Processing,Institute of Biophysics,Chinese Academy of sciences,Beijing 100101,china hefei national laboratory for physical sciences at microscale and school of life science University of Science and Technology of China Hefei China laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Aim:To investigate the effect of chronic morphine exposure on the receptive fieldproperties of lateral geniculate nucleus(LGN)neurons in ***:Catswere injected with morphine(10 mg/kg)or saline twice daily,for 10 ***,extracellular single-unit recording techniques were used to examine the sensitivityof LGN neurons to visual stimuli in chronic morphine-treated and ***:Compared with saline-treated cats(as controls),LGN neurons inmorphine-treated cats had decreased signal-to-noise ratios(1.9 vs 3.1 ),and orien-tation and direction sensitivity(0.103 vs O.135 and 0.074 vs O.10,respectively),accompanied by significant increases in spontaneous(27.4 vs 17.5)and evokedactivity(preferred:42.2 vs 38.1;average:28.1 vs 22.3).Conclusion:Chronic mor-phine exposure can lead to the functional degradation of LGN neurons in cats,which might result from the effects of chronic morphine exposure on inhibitoryneurotransmission.

关键词： direction sensitivity orientation sensitivity signal-to-noise ratio spontaneous response evoked response

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Porous Y_2O_3 microcubes:synthesis and characterization

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Rare Metals 2011年第6期30卷 577-582页

作者： DENG Bin DING Liwen CHEN Jianjun ZHONG Shengliang Department of Chemistry and life sciences Xiangnan University Chenzhou 423000 China College of Chemistry and Chemical Engineering Jiangxi Normal University Nanchang 330022 China Division of Nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technology of China Hefei 230026 China

In this work, a facile route using a simple solvothermal reaction and sequential heat treatment process to prepare porous Y2O3 microcubes is presented. The as-synthesized products were characterized by X-ray powder diffraction （XRD）, scanning electronic microscope （SEM）, energy dispersive spectrometer （EDS）, thermogravimetric analysis （TG）, and differential thermal analysis （DTA）. The thermal decomposition process of the Y203 precursor was investigated. SEM results demonstrated that the as-prepared porous Y203 microcubes were with an average width of about 20 μm and thickness of about 8μm. It was found that the morphology of the Y2O3 precursor could be readily tuned by varying the molar ratio of S2O2- to y3＋. Y203：Eu3＋（6.6%） microcubes were also prepared and their photoluminescence properties were investigated.

关键词： yttrium oxide yttrium sulfate solvothermal synthesis porous material

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Alekseevskii-Tate revisited:An extension to the modified hydrodynamic theory of long rod penetration

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science china(Technological sciences) 2010年第5期53卷 1364-1373页

作者： LAN Bin & WEN HeMing CAS Key laboratory for Mechanical Behavior and Design of Materials,university of science and technology of china,hefei 230027,china CAS Key laboratory for Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei China

The modified hydrodynamic theory of long rod penetration into semi-infinite targets was established independently by Alek-seevskii and Tate over forty years ago and since then many investigators contributed much to the development of the high speed penetration ***,in all the models proposed so far,the target resistance Rt is not well defined and usually determined by adjusting it until the predicted depth of penetration comes to an agreement with experimental *** this paper,assumptions are first made about particle velocity and pressure profiles together with response regions in the target and then an extension is made to the modified hydrodynamic theory of long rod penetration into semi-infinite targets,in which Rt has explicit form and is dependent on penetration velocity as well as thermo-mechanical properties of target *** present model is compared with long rod penetration tests for different material *** transpires that the present model predictions are in good agreement with the experimental data and numerical simulations in terms of penetration depth although many assumptions and simplifications are introduced into the paper.

关键词： long rod semi-infinite target penetration Alekseevskii-Tate model

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Re-Os isotopic system and formation age of subcontinental lithosphere mantle

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Chinese science Bulletin 2000年第3期45卷 193-200页

作者： ZHI XiachenDepartment of Earth and Space sciences, university of science and technology of china, hefei 230026, china Advance Research Center for Earth science and Astronomy, USTC, Third World Academy of science, hefei 230026, china laboratory of Chemical Geodynamics, USTC, hefei 230026, china Department of Earth and Space sciences University of Science and Technology of China Hefei China Advance Research Center for Earth science and Astronomy USTC Third World Academy of Science Hefei China laboratory of Chemical Geodynamics USTC Hefei China

The determination of the formation age of subcontinental Lithosphere Mantle (SCLM) is a widely concerned issue in mantle geochemistry. it is difficult to obtain the formation age of SCLM using lithophile isotopic systems such as Rb-Sr, Sm-Nd, U-Th-Pb, ete., but as siderophile elements, the Re-Os isotopic system provides a powerful tool for that work. Here a comprehensive review on the recent development in Re-Os dating for SCLM has been given.

关键词： Re-Os isotopic dating subcontinental lithospheric mantle mantle derived peridotites Re depleted model age whole rock isochronological age.

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