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CagA^+ *** Induces Akt1 Phosphorylation and Inhibits Transcription of p21^(WAF1/CIP1) and p27^(KIP1) via PI3K/Akt1 Pathway

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Biomedical and Environmental Sciences 2010年第4期23卷 273-278页

作者： SHU-PING LI xue-JUN CHEN AI-HUA SUN JIN-fang zhao JIE YAN State Key Laboratory for Diagnosis and Treatment of Infectious Diseases the First Affiliated Hospital of Zhejiang University Hangzhou 310003 Zhejiang China Department of Clinical Laboratory The Children's Hospital of Zhejiang University Hangzhou 310003 Zhejiang China Faculty of Basic Medicine Zhejiang Medical College Hangzhou 310053 Zhejiang China Department of Medical Microbiology and Parasitology Medical College of Zhejiang University Hangzhou 310058 Zhejiang China

Objective Cytotoxin-associated protein （CagA） of H. pylori has been confirmed to be closely associated with gastric inflammation and tumorigenesis, but the mechanism behind it is little understood. In this study, we try to determine roles of CagA＋ strain in activating PI3K/Akt1 signaling pathway, and affecting expression of p21WAF1/CIP1 and p27KIP1, and also in releasing IL-8 in host cells. Methods Akt1 phosphorylation and IL-8 levels of CagA＋ and CagAˉ strain infected AGS cells were detected by ELISAs. Two quantitative RT-PCRs were established to measure p21WAF1/CIP1 and p27KIP1 mRNA levels in the CagA＋ and CagAˉ strain infected cells. LY294002, an inhibitor of PI3K/Akt pathway, was used to define effect of the pathway in IL-8 release. Results CagA＋ strain could induce an obvious elevation of Akt1 phosphorylation in the infected AGS cells while CagAˉ strain failed to do so. The CagA＋ H. pylori strain infected AGS cells showed significant drops both in p21WAF1/CIP1 and p27KIP1 mRNA levels, whereas the CagAˉ H. pylori strain caused a remarkable increase in p21WAF1/CIP1 mRNA without affecting p27KIP1 gene transcription in the AGS cells. Both the CagA＋ and CagAˉ H. pylori strains enabled AGS cells to produce close elevated levels of IL-8, and the LY294002 block resulted in unexpected elevations of IL-8 levels. Conclusion CagA can activate PI3K/Akt1 pathway that plays an inhibitory role in IL-8 release in H. pylori infected AGS cells. Activation of PI3K/Akt1 pathway and subsequent negative regulation of p21^WAF1/CIP1 and p27^KIP1 expression might be involved in CagA-associated carcinogenesis.

关键词： Helicobater pylori CagA PI3K Akt1 p21^WAF1/CIP1 p27^KIP1 IL-8

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BF_3·Et_2O promoted conjugate addition of ethanethiol to electron-deficient alkynes

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Chinese Chemical Letters 2012年第6期23卷 639-642页

作者： Qing Fa Zhou xue Ping Chu Shen zhao Tao Lu Wei fang Tang Department of Organic Chemistry China Pharmaceutical University Nanjing 210009 China

An effective method for the synthesis of vinyl thioethers through the conjugate addition of ethanethiol to electron-deficient alkynes promoted by ***20 has been developed. Electron-deficient internal alkynes react with ethanethiol in this system to yield mainly Z-isomer of vinyl thioether adducts, while electron-deficient terminal alkynes afford mainly E-isomer of vinyl thioether adducts.

关键词： Vinyl thioether Electron-deficient alkyne Conjugate addition Synthesis

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Udwadia–Kalaba Equation for Constrained Mechanical Systems:Formulation and Applications

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 11-24页

作者： Xiao-Min zhao Ye-Hwa Chen Han zhao fang-fang Dong School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009China The George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA School of Mechanical Engineering Hefei University of TechnologyHefei 230009China

There are many achievements in the field of analytical mechanics, such as Lagrange Equation, Hamilton’s Principle, Kane’s Equation. Compared to Newton–Euler mechanics, analytical mechanics have a wider range of applications and the formulation procedures are more mathematical. However, all existing methods of analytical mechanics were proposed based on some auxiliary variables. In this review, a novel analytical mechanics approach without the aid of Lagrange’s multiplier, projection, or any quasi or auxiliary variables is introduced for the central problem of mechanical systems. Since this approach was firstly proposed by Udwadia and Kalaba, it was called Udwadia–Kalaba Equation. It is a representation for the explicit expression of the equations of motion for constrained mechanical systems. It can be derived via the Gauss’ s principle, d’Alembert’s principle or extended d’Alembert’s principle. It is applicable to both holonomic and nonholonomic equality constraints, as long as they are linear with respect to the accelerations or reducible to be that form. As a result, the Udwadia–Kalaba Equation can be applied to a very broad class of mechani?cal systems. This review starts with introducing the background by a brief review of the history of mechanics. After that, the formulation procedure of Udwadia–Kalaba Equation is given. Furthermore, the comparisons of Udwadia–Kalaba Equation with Newton–Euler Equation, Lagrange Equation and Kane’s Equation are made, respectively. At last, three di erent types of examples are given for demonstrations.

关键词： Udwadia–Kalaba Equation Mechanical system Constraint Moore–Penrose inverse

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Synthesis and in vitro-Anti-hepatitis B Virus Activities of Several Ethyl 5-Hydroxy-1H-indole-3-carboxylates

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Chemical Research in Chinese Universities 2006年第5期22卷 577-583页

作者： zhao Chun-shen zhao Yan-fang CHAI Hui-fang GONG Ping Liaoning Province Key Laboratory of Innovative Medicine Research and Design Shenyang Pharmaceutical University Shenyang 110016 P. R. China

A series of ethyl 5-hydroxyindole-3-earboxylates 6a-10r was designed and synthesized. The structures of all the compounds were confirmed by IR, ^1H NMR, and MS and their anti-hepatitis B virus （HBV） activities were evaluated in 2.2.15 cells. Among them, compound 7g { ethyl 5-hydroxy-2- [ （ 3-methoxyphenylsulfinyl ） methyl ] -1-methyl-4- [ （4-methylpiperazin-1-yl） methyl ]-1H-indole-3-carboxylate} displays a significant anti-HBV activity, which is more potent than the positive control lamivudine.

关键词： Ethyl 5-hydroxy-1H-indole-3-carboxylates Synthesis Anti-hepatitis B virus activity

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Determination of Scaling Parameter and Dynamical Resonances in Complex-Rotated Hamiltonian Ⅰ:Theory

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Communications in Theoretical Physics 2008年第3期49卷 599-606页

作者： zhao fang zhao Mei-Shan Department of Mathematics and Department of Chemistry The University of Chicago Chicago Illinois 60637 USA The James Pranck Institute and Department of Chemistry The University of Chicago Chicago Illinois 60637 USA

In this paper we present a theoretical analysis on the determination of the scaling parameter in the complex-rotated Hamiltonian, which has served as a basis for successful applications of the rigged Hilbert space theory for resonances. Based on the complex energy eigenvalue, E（θ） = ER（θ） - iГ（θ）/2, as a function of the scaling parameter θ, we find that for potential barrier scattering, the condition dГ（θI）/dθ = 0 uniquely determines the scaling parameter 8. The condition d ER （θR）/ dθ = 0 is merely a consequence of the Virial theorem and θI =θR is not a necessary condition for a resonance state. We also provide a harmonic approximation formMism for resonances in scattering over a potential barrier.

关键词： complex-rotated Hamiltonian potential scattering resonances rigged Hilbert space

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Measurement of the peripheral aberrations of human eyes:A comprehensive review

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Nanotechnology and Precision Engineering 2020年第2期3卷 53-68页

作者： Yanbo zhao Fengzhou fang Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland State Key Laboratory of Precision Measuring Technology and Instruments Centre of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072China

It has been nearly 50 years since the first glimpse of the relationship between myopia and peripheral refractive errors. According to experiments on both animals and humans, the eyes with hyperopic peripheral vision appear to be at higher risk of developing myopia than those with myopic peripheral refractive errors. Despite the first measurement of peripheral refraction being achieved by a modified manual optometer, the concept of emmetropization triggered a rapidly increasing number of studies on peripheral aberrations. Not only the horizontal off-axis aberrations but also the meridional aberrations at different angles are measured by researchers during the development of peripheral aberrations measuring techniques. According to the differences among the working principles, a variety of techniques have been adopted for performing such measurements. The methods developed to realize the high-performance measurement involve the subject cooperating actively by rotating the head or eyes, the rotation of the whole optical path, and the combination of measurements of many light paths. This paper provides a review of the peripheral aberrations measuring techniques and their current status. This article also highlights the development trend of the measuring techniques of peripheral aberrations and practical applications of peripheral aberration measurements, such as the control of the accommodation, the measuring time, and the dynamic range problem of the wavefront sensor. Although wavefront sensing peripheral measurement is widely recognized for its capability to reveal both lower-order aberrations and higher-order aberrations, the efficiency of an autorefractometer is incomparable. The current study reveals that the most widely used peripheral aberration measurement methods are the use of an open field autorefractometer and Hartman-shack wavefront sensor-based techniques.

关键词： Peripheral aberrations Myopia control Open field autorefractometer Hartman-shack wavefront sensor-based techniques

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Halogen Storage Electrode Materials for Rechargeable Batteries

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Energy & Environmental Materials 2022年第4期5卷 1155-1179页

作者： Zhiyang xue Zhengyuan Gao Xiangyu zhao State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu Collaborative Innovation Center for Advanced Inorganic Functional CompositesCollege of Materials Science and EngineeringNanjing Tech UniversityNanjing 211816China

The ever-increasing demand for rechargeable batteries with high energy density,abundant resources,and high safety has pushed the development of various battery technologies based on cation,anion,or dual-ion *** use of halogen storage electrode materials has led to new concept battery systems such as halide-ion batteries(HIB)and dual-ion batteries(DIB).This review highlights the recent progress on these electrode materials,including metal(oxy)halides,layered double hydroxides,MXenes,graphite-based materials,and organic materials with carbon or nitrogen redox *** reversible electrochemical halogen storage of halide ions(e.g.,F^(−),Cl^(−),and Br^(−)),dual halogen(e.g.,Br_(m)Cl_(n) and [ICl_(2)]^(−)),or binary halide anions(e.g.,PF_(6)^(−),AlCl_(4)^(−),[ZnCl_(x)]^(2−x),and [MgCl_(x)]^(2−x)) in the electrodes is *** challenges and mechanisms of halogen storage in various electrode materials in HIBs and DIBs are summarized and analyzed,providing insights into the development of high-performance halogen storage electrode materials for rechargeable batteries.

关键词： dual-ion batteries electrode materials halide-ion batteries halogen storage rechargeable batteries

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Determination of ammonium on an integrated microchip with LED-induced fluorescence detection

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Journal of Environmental Sciences 2012年第3期24卷 564-570页

作者： Shuhua xue Katsumi Uchiyama Hai-fang Li Department of Chemistry Tsinghua UniversityBeijing 100084China College of Chemistry and Chemical Engineering Fuzhou UniversityFuzhou 350108China Department of Applied Chemistry Graduate School of Urban Environmental SciencesTokyo Metropolitan UniversityMinamiohsawaHachiojiTokyo 192-0364Japan

A simply fabricated microfluidic device integrated with a fluorescence detection system has been developed for on-line determination of ammonium in aqueous samples. A 365-nm light-emitting diode （LED） as an excitation source and a minor band pass filter were mounted into a polydimethylsiloxane （PDMS）-based microchip for the purpose of miniaturization of the entire analytical system. The ammonium sample reacted with o-phthaldialdehyde （OPA） on-chip with sodium sulfite as reducing reagent to produce a fluorescent isoindole derivative, which can emit fluorescence signal at about 425 nm when excited at 365 nm. Effects of pH, flow rate of solutions, concentrations of OPA-reagent, phosphate and sulfite salt were investigated. The calibration curve of ammonium in the range of 0.018- 1.8 μg/mL showed a good linear relationship with R2 = 0.9985, and the detection limit was （S /N = 3） 3.6 × 10 4 μg/mL. The relative standard deviation was 2.8% （n = 11） by calculating at 0.18 μg/mL ammonium for repeated detection. The system was applied to determine the ammonium concentration in rain and river waters, even extent to other analytes fluorescence detection by the presented device.

关键词： microfluidic chip light emitting diode o-phthaldialdehyde fluorescence ammonium

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In Situ Variation of Interpenetrating Polymer Network Topology using a Photolabile Connector

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Chinese Journal of Polymer Science 2022年第11期40卷 1317-1322页

作者： Xin-Hong Xiong Lu-Lu xue Sheng Wang Shi-fang zhao Xiang Guo Mei Li Jia-Xi Cui Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China Department of Bioengineering University of PennsylvaniaPhiladelphiaPennsylvania19104USA College of Chemistry and Molecular Engineering Peking UniversityBeijing100871China School of medicine Shaoxing UniversityShaoxing312000China School of Materials Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu610054China

A photo-controlled approach is developed to regulate the interpenetrating polymer network(IPN)topology by varying the connecting structure between the first and second *** approach is based on multifunctional inimer(Vinyl-o NB-Br)possessing three moieties,i.e.,an acrylate-based double bond for incorporation within a polymer network,a Br group for grafting polymerization to get connectIPN(c-IPN),and an o-nitrobenzyl spacer for photocleaving to convert the c-IPN to disconnected-IPN(d-IPN)with UV light *** design allows for finely controlling the connection degree between two networks.A systematic study on the mechanical property of a series of samples with different connection degrees thus can be *** results reveal that decreasing the connecting degree between two networks of IPN made a negligible contribution to materials'mechanical properties.

关键词： Interpenetrating polymer network Network topology o-Nitrobenzyl Inimer Mechanical property

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Highly Efficient and Thermal Robust Cobalt Complexes for 1,3-Butadiene Polymerization

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Chinese Journal of Polymer Science 2022年第11期40卷 1369-1379页

作者： Liang fang Wen-Peng zhao Chun-Yu Zhang xue-Quan Zhang Xian-De Shen Heng Liu Toyoji Kakuchi Research Center for Polymer Materials School of Materials Science and EngineeringChangchun University of Science and TechnologyJilin130022China Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science&TechnologyQingdao266061China Division of Applied Chemistry Faculty of EngineeringHokkaido UniversitySapporoHokkaido060-8628Japan

A family of highly bulky bis(salicylaldiminate)Co(Ⅱ)complexes bearing cavity-like conformations are disclosed *** to their unique bulky nature around the cobalt atoms that are reflected from space-filling models and the buried volume percentages,obviously longer bond distances of Co―N and Co―O are revealed from those ***,because of these well-protected active species,the cobalt complexes are able to catalyze 1,3-butadiene polymerization in high yields at extreme low catalyst concentrations,revealing a ultra high catalytic *** a ratio of 50000,all the complexes can afford polybutadiene with yields higher than 90%.Furthermore,the highly steric bulkiness of the ligand can also significantly enhance the thermostability of the active *** temperature of 80-120°C,the complexes are able to successfully maintain high activities,giving polymer yields up to 90%.

关键词： Butadiene polymerization Bis(salicylaldiminate)Co(Ⅱ)complexes Ultra high catalytic efficiency

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