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Crystalline,Rheological and Mechanical Enhancement in PBAT/PPC/Silica Nanocomposites with Double Percolation Network

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Chinese Journal of Polymer Science 2022年第11期40卷 1482-1492页

作者： You-mei ma Feng-Xiang Gao Shu-Ling Zhang College of Chemistry Jilin UniversityChangchun130012China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

Nanocomposites of blends of biodegradable poly(butylene adipate-co-terephthalate)(PBAT)and sustainable poly(propylene carbonate)(PPC)with nanosilica were prepared by melt compounding ***/PPC blend was partially miscible system with sea-island structure,and nanosilica particles were selectively dispersed in the continuous phase PBAT matrix to form the double percolation *** introduction of nanosilica into PBAT/PPC blend reduced the size of dispersed PPC phase,promoted the crystallization of PBAT in the nanocomposites,and increased the storage modulus of the *** study of rheological behaviors indicated that the double percolation network was formed at the nanosilica loading of 5 wt%,as a result,the nanocomposites exhibited the solid-like viscoelastic behavior and their relaxation time was *** the increase of the nanosilica content,the PBAT/PPC/silica nanocomposites displayed increased Young's modulus and yield strength.

关键词： Nanocomposites Selective dispersion Double percolation Enhanced properties

Peroxisome proliferator-activated receptor-γ is essential in the pathogenesis of gastric carcinoma

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World Journal of Gastroenterology 2009年第31期15卷 3874-3883页

作者： Xiu-mei ma Hong Yu Na Huai Department of Pathology The First Affiliated Hospital of Inner Mongolia Medical College Huhhot 010059 Inner Mongolia Autonomous Region China Department of Pathology School of Basic Medical Sciences of Inner Mongolia Medical College Huhhot 010059 Inner Mongolia Autonomous Region China The Graduate Faculty of Inner Mongolia Medical College Huhhot 010059 Inner Mongolia Autonomous Region China

AIM： To investigate whether peroxisome proliferatoractivated receptor γ （PPAR-γ） is expressed in human gastric carcinoma and whether PPAR-γ, is a potential target for gastric carcinoma therapy. METHODS： PPAR-γ protein in gastric carcinoma was examined by immunohistochemistry. In the gastric carcinoma cell line MGCS03, PPAR-7, survivin, Skp2 and p27 protein and mRNA were examined by Western blotting and real-time reverse transcription-polymerase chain reaction, respectively; proliferation was examined by MTT; apoptosis was examined by chromatin staining with Hoechst 33342 and fluorescence activated cell sorting （FACS）. and cell cycle was examined by FACS; the knockdown of PPAR-γ was done by RNA interference. RESULTS： A high level of expression of PPAR-γ was observed in human gastric carcinoma and in a human gastric carcinoma cell line MGCS03. The PPAR-γ agonist 15-deoxy-△12,14-prostaglandin J2 （15d-PGJ2）inhibited growth, and induced apoptosis and G1/G0 cell cycle arrest in MGC803 cells in a concentration-dependent and time-dependent manner. The effect of 15d-PGJ2 on MGC803 cells was not reversed by the selective and irreversible antagonist GW9662 for PPAR-γ. Furthermore, survivin and Skp2 expression were decreased, whereas p27 expression was enhanced following 15d-PGJ2 treatment in a dose-dependent manner in MGC803 cells. Interestingly, we also found that small interfering RNA for PPAR-γ inhibited growth and induced apoptosis in MGC803 cells. The inhibition of PPAR-γ function may be a potentially important and novel modality for treatment and prevention of gastric carcinoma. CONCLUSION： A PPAR-γ agonist inhibited growth of human gastric carcinoma MGC803 cells by inducing apoptosis and G1/G0 cell cycle arrest with the involvement of survivin, Skp2 and p27 and not via PPAR-γ.

关键词： Peroxisome proliferator-activated receptor Gastric cancer Apoptosis Cell cycle

magnetic Long-Range Order and Colossal magnetoresistance Effect in Double Exchange Ladders

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Chinese Physics Letters 2001年第9期18卷 1264-1267页

作者： ma Dong-mei ZOU Liang-Jian Institute of Solid State Physics Chinese Academy of SciencesHefei 230031 National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

By applying Bogoliubov's ineguality to double-exchange(DE) ladders, we show that the ferromagnetic(FM) order is absent in the new DE systems at finite temperatures. The incorporation of Jahn-Teller electron-phonon coupling, orbital degeneracy and on-site Coulomb interaction with the DE interaction do not preserve these orders. The long-wavelength thermal fluctuations of the spins oversome the DEFM correlation and destroy the FM orders. The implication of the absence of FM order on the transport of the DE ladders is discussed.

关键词： orders interaction ladder

In vitro thyroid disrupting effects of organic extracts from WWTPs in Beijing

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Journal of Environmental Sciences 2011年第4期23卷 671-675页

作者： Na Li mei ma Kaifeng Rao Zijian Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

It is generally known that there are many endocrine disrupting compounds （EDCs） in the effluents from wastewater treatment plants （WWTPs）. Most research has focused on the occurrence of estrogenic or androgenic activities, while ignoring that there are environmental chemicals disrupting thyroid system, which is essential for growth and development in both humans and animals. In the present work, a two-hybrid yeast assay was conducted to evaluate the removal efficiencies of agonistic or antagonistic thyroid receptor （TR） mediated effects in different treatment processes of three WWTPs located in Beijing. We found no TR agonistic, but TR antagonistic activities in all processes from the WWTPs. The TR antagonistic activities in organic extracts of water samples were then calibrated regarding to a known TR-inhibitor, amiodarone hydrochloride （AH）. The observed concentration of TR disrupting substances ranged from 2.35 × 10 8 to 6.19 × 10 7 mol/L AH in Gaobeidian WWTP, 3.76 × 10 8 to 8.75 × 10 8 mol/L AH in Lugouqiao WWTP, and 4.80 × 10 9 to 2.55 × 10 8 mol/L AH in Beixiaohe WWTP. Of the three WWTPs, the removal rates were 92.7%, 42.2%, and 23.1% respectively. Industrial sewage may contain more TR disrupting substances compared with domestic sewage. The recipient waters were found to contain considerable concentrations of TR disrupting substances that may cause adverse effects on the exposed organisms.

关键词： recombinant yeast assay thyroid receptor wastewater

Simultaneous quantification of ten constituents of Xanthoceras sorbifolia Bunge using UHPLC-MS methods and evaluation of their radical scavenging, DNA scission protective, and α-glucosidase inhibitory activities

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Chinese Journal of Natural Medicines 2015年第11期13卷 873-880页

作者： ZHANG Yu ma Jian-Nan ma Chun-Li QI Zhi ma Chao-mei School of Life Sciences Inner Mongolia University

The present study was designed to investigate the bioactive constituents ofXanthoceras sorbifolia in terms of amounts and their antioxidant, DNA scissiou protection, and ct-glucosidase inhibitory activities. Simultaneous quantification of 10 X. sorbifolia constituents was carried out by a newly established ultra-high performance liquid chromatography-quadrupole mass spectrometry method （UHPLC-MS）, The antioxidant activities were evaluated by measuring DPPH radical scavenging and DNA scission protective activities. The a-glucosidase inhibitory activities were investigated by using an assay with a-glucosidase from Bacillus Stearothermophilus and disaccharidases from mouse intestine. We found that the wood ofX. sorbifolia was rich in phenolic compounds with the contents of catechin, epicatechin, myricetin, and dihydromyricetin being 0.12-0.19, 1.94-2.16, 0.77-0.91, and 6.76-7.89 mg.g-1, respectively. The four constituents strongly scavenged DPPH radicals （with ECs0 being 4.2, 3.8 and 5.7 μg-mL-1, respectively） and remarkably protected peroxyl radical-induced DNA strand scission （92.10%, 94.66%, 75.44% and 89.95% of protection, respectively, at a concentration of 10 μmol.L-1）. A dimeric flavan 3-ol, epigallocatechin-（4β→8, 2β→O-7）-epicatechin potently inhibited a-glucosidase with an IC50 value being as low as 1.2 μ***1. The established UHPLC-MS method could serve as a quality control tool for X. sorbifolia. In conclusion, the high contents of antioxidant and α-glucosidase inhibitory constituents in X. sorbifolia support its use as complementation of other therapeutic agents for metabolic disorders, such as diabetes and hypertension.

关键词： Xanthoceras sorbifolia Constituents Quantification Antioxidant DNA scission protective α-glucosidase inhibition

Molecular Generation and Optimization of Molecular Properties Using a Transformer Model

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Big Data Mining and Analytics 2024年第1期7卷 142-155页

作者： Zhongyin Xu Xiujuan Lei mei ma Yi Pan School of Computer Science Shaanxi Normal UniversityXi'an 710119China Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Generating novel molecules to satisfy specific properties is a challenging task in modern drug discovery,which requires the optimization of a specific objective based on satisfying chemical ***,we aim to optimize the properties of a specific molecule to satisfy the specific properties of the generated *** matched Molecular Pairs(MMPs),which contain the source and target molecules,are used herein,and logD and solubility are selected as the optimization *** main innovative work lies in the calculation related to a specific transformer from the perspective of a matrix *** intervals and state changes are then used to encode logD and solubility for subsequent *** the experiments,we screen the data based on the proportion of heavy atoms to all atoms in the groups and select 12365,1503,and 1570 MMPs as the training,validation,and test sets,*** models are compared with the baseline models with respect to their abilities to generate molecules with specific *** show that the transformer model can accurately optimize the source molecules to satisfy specific properties.

关键词： molecular optimization transformer matched Molecular Pairs(MMPs) logD solubility

In vitro agonistic and antagonistic endocrine disrupting effects of organic extracts from waste water of different treatment processes

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Frontiers of Environmental Science & Engineering 2014年第1期8卷 69-78页

作者： Kaifeng RAO Na LI mei ma Zijian WANG State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Effluents from wastewater treatment plant （WWTP） have been reported to have a broad spectrum of endocrine disrupting compounds （EDCs）. The majority of studies have focused on the occurrence of estrogenic activity, while ignoring nuclear hormone receptors （NRs） pathways. In the present study, a battery of in vitro yeast bioassays and a cell bioassay, including antagonistic and agonistic effects on estrogen receptor （ER）, androgen receptor （AR）, progesterone receptor （PR）, estrogen- related receptor （ERR） and aryl hydrocarbon receptor （AHR）, were conducted to evaluate the removal efficien- cies of EDCs by different treatment processes of a WWTP located in Beijing. Estrogenic, anti-estrogenic, anti- androgenic, anti-progesteronic, anti-ERR and the activa- tion of AHR activities were detected in samples from all treatment processes and the receiving water. The concen- tration of estrogenic contaminants with estradiol （E2） equivalent concentrations ranged from 0.82 x 10-9 to 3.54 x 10 9g Ee_EQ.L-1. The concentration of anti-estrogenic contaminants with 4-hydroxytamoxifen （4-OHT） equiva- lent concentrations ranged from 1.24 × 10-6 to 2.36 x 10-6 g 4-OHT-EQ.L-1. The concentration of anti-androgenic contaminants ranged from 2.21 x 10-s to 3.52 × 10-6g flutamide-EQ. L-1. The concentration of anti-progesteronic contaminants ranged from 3.15 x 10^-5 to 2.71 x 10^-4g RU486-EQ. L-1. The concentration of anti-ERR contami- nants ranged from 7.09 x 10-5 to 6.50 x 104 g 4-OHT-EQ × L^-10. The concentration of AHR activators ranged from 1.7 × 10-10 to 3.4 × 10^-10g TCDD-EQ-L-1. These processes including secondary clarifier, coagulation, as well as coal and sand filtration could eliminated 67.2% of estrogenic contaminants, 47.0% of anti-estrogenic contaminants, 98.3% of anti-androgenic contaminants, 88.4% of anti- progesteronic contaminants, 65.4% of anti-ERR contami- nants and 46.9% of AHR activators. WWTP effluents contain multiple receptor disruptors may have very complex adverse ef

关键词： waste water in vitro recombinant yeast assay,ethoxyresomfin-O-deethylase (EROD) receptor endocrine

Reaction Kinetics of Trans-Sobrerol and 8-p-Menthen-1,2-diol with Hydroxyl Radical in Aqueous Solution： A Combined Experimental and Theoretical Study

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Chinese Journal of Chemical Physics 2015年第3期28卷 308-314,I0001,I0002页

作者： Yan Long Xin Tong Tong-mei ma Li-ming Wang School of Chemistry & Chemical Engineering South China University of Technology Guangzhou 510640 China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control South China University of Technology Guangzhou 510006 China

Trans-sobrerol （Sob） and 8-p-menthen-1,2-diol （Limo-diol） are the primary products in the atmospheric oxidation of α-pinene and limonene, respectively. Because of their low volatility, they associate more likely to the liquid particles in the atmosphere, where they are subject to the aqueous phase oxidation by the atmospheric oxidants. In this work, through experimental and theoretical study, we first provide the rate constants of Sob and Limo-diol reacting with hydroxyl radical （.OH） in aqueous solution at room temperature of 3044-3 K and 1 atm pressure, which are （3.05±0.5）×10 9 and （4.57±0.2）×10 9 L/（mol.s）, respectively. Quantum chemistry calculations have also been employed to demonstrate the solvent effect on the rate constants in aqueous phase and the calculated results agree well with the measurements. Some reaction products have been identified based on liquid chromatography combined with mass spectroscopy and theoretical calculations.

关键词： Unsaturated alcohols Hydroxyl radical Aqueous-phase reaction Kinetic Theoretical calculations

Determination of estrogens and estrogenic activities in water from three rivers in Tianjin, China

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Journal of Environmental Sciences 2013年第6期25卷 1164-1171页

作者： Kaifeng Rao Bingli Lei Na Li mei ma Zijian Wang Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Environmental Pollution and Health College of Environmental and Chemical EngineeringShanghai University Key Laboratary for Biomedical Effects of Nanomaterials and Nanosafety Key Laboratory of Nuclear Analytical TechniquesInstitute of High Energy PhysicsChinese Academy of Sciences

Studies on estrogenic disrupting compounds （EDCs） occurrence and identification of main responsible compounds in river water discharged into the sea are of significance. In the present research, we screened estrogenic activities of 10 river water samples from 3 main rivers discharged into Bohai Sea in Tianjin using a recombinant two-hybrid yeast assay and chemical analysis by gas chromatography-mass spectrometry. All sample extracts induced significant estrogenic activity, with 17^-estradiol equivalents （EEQ） of raw water ranging from 5.72 to 59.06 ng/L. Six most concerned EDCs in the fiver water samples including estrone, 17（5-estradiol, 17ct-ethinylestradiol, estriol, diethylstilbestrol and estradiol valerate were determined, with their concentrations up to 50.70, 31.40, 24.40, 37.20, 2.56, and 8.47 ng/L, respectively. Through causality analysis by comparing the EEQ values of yeast assay and chemical analysis, 17ct-ethinylestradiol and 17[3-estradiol were identified as the main contributors to the estrogenic effects of the river samples, accounting for the whole estrogenic activities （62.99% to 185.66%）, and estrogen antagonistic compounds might presented in the heavy polluted water samples. The proposed approach using both chemical analysis and bioassay could be used for identification and evaluation of the estrogenic activity of EDCs in river water.

关键词： river water endocrine disrupting compounds (EDCs) yeast assay bioassay