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Cleavage of the Carboxyl-Terminus of LEACS2, a Tomato 1-Aminocyclopropane-l-Carboxylic Acid Synthase Isomer, by a 64-kDa Tomato Metalloprotease Produces a Truncated but Active Enzyme

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Journal of Integrative Plant Biology 2005年第11期47卷 1352-1363页

作者： Jian-Feng LI robert qi Liang-Hu QU Autar K Mattoo Ning LI Department of Biology The Hong Kong University of Science and Technology Hong Kong SAR China Key Laboratory of Gene Engineering of the Ministry of Education Zhongshan University Guangzhou 510275 China Department of Biochemistry The Hong Kong University of Science and Technology Hong Kong SAR China Sustainable Agricultural Systems Laboratory United States Department of Agriculture-Agriculture Research Service Beltsville Maryland 20705-2350 USA

1-Aminocyclopropane-1-carboxylic acid （ACC） synthase （ACS） is the principal enzyme in phytohormone ethylene biosynthesis. Previous studies have shown that the hypervariable C-terminus of ACS is proteolytically processed in vivo. However, the protease responsible for this has not yet been identified. In the present study, we investigated the processing of the 55-kDa full-length tomato ACS （LeACS2） into 52-, 50- and 49-kDa truncated isoforms in ripening tomato （Lycopersicon esculentum Mill. cv. Cooperation 903） fruit using the sodium dodecyl sulfate-boiling method. Meanwhile, an LeACS2-processing protease was purified via multi-step column chromatography from tomato fruit. Subsequent biochemical analysis of the 64-kDa purified protease revealed that it is a metalloprotease active at multiple cleavage sites within the hypervariable C-terminus of LeACS2. N-terminal sequencing and matrix-assisted laser desorption/ionization time-of-flight analysis indicated that the LeACS2-processing metalloprotease cleaves at the C-terminal sites Lys^438, Glu^447, Lys^448, Asn^456, Ser^460, Ser^462, Lys^463, and Leu^474, but does not cleave the N- terminus of LeACS2. Four C-terminus-deleted （26-50 amino acids） LeACS2 fusion proteins were overproduced and subjected to proteolysis by this metalloprotease to identify the multiple cleavage sites located on the N-terminal side of the phosphorylation site Ser^460. The results indisputably confirmed the presence of cleavage sites within the region between the α-helix domain （H14） and Ser^460 for this metalloprotease. Furthermore, the resulting C-terminally truncated LeACS2 isoforms were active enzymatically. Because this protease could produce LeACS2 isoforms in vitro similar to those detected in vivo, it is proposed that this metalloprotease may be involved in the proteolysis of LeACS2 in vivo.

关键词： 1-aminocyclopropane-1-carboxylic acid synthase cleavage sites metalloprotease proteolytic processing.

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Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

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Neural Regeneration Research 2025年第3期20卷 740-750页

作者： Yuchen Zhang Yiqing Chen Cheng Zhuang Jingxuan qi robert Chunhua Zhao Jiao Wang School of Life Sciences Shanghai UniversityShanghaiChina School of Medicine Shanghai UniversityShanghaiChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic MedicinePeking Union Medical CollegeBeijingChina Center of Excellence in Tissue Engineering Chinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory of New Drug Development and Clinical Trial of Stem Cell Therapy BeijingChina

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous *** droplet formation begins with the synthesis of neutral lipids in the endoplasmic ***,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous *** addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress ***,lipid droplets exhibit specific functions in neurons and glial *** of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system *** review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and ***,it will explore the association between lipid droplets and neurodegenerative *** the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

关键词： Alzheimer's disease lipid droplet biogenesis lipid droplets lipid metabolism nervous system neurodegenerative disorders oxidative stress Parkinson's disease

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Leaching of the residue from the dry off-gas de-dusting and desulfurization process of an iron ore sinter plant

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 116-121页

作者： Christof Lanzerstorfer qi Xu robert Neuhold School of Engineering/Environmental Sciences University of Applied Sciences Upper Austria Siemens VAI Metals Technologies GmbH

The residue from a second-stage dry sinter plant off-gas cleaning process contains both the fine dust from the sinter plant and the sorbent used. Recycling of the material that is usually handled by landfills to the sinter plant feed is not possible because of its chloride con- tent. Leaching of the chlorides allow the recycling of remaining solids. The saline leachate produced contains some heavy metals and must be treated before it is discharged into the sea. In laboratory experiments, leaching tests with the subsequent treatment of the leachate were con- ducted. After the process was optimized, all heavy-metal concentrations were below the permissible values. The optimum treatment condi- tions for heavy-metal precipitation were observed to be the filtration of the suspended solids followed by the dosing of liquid with lime milk （pH 10） and the subsequent precipitation using sodium sulfide.

关键词： heavy metals off-gas cleaning recycling residues leaching sinter plants

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不同转移能力乳腺癌细胞株的差异表达蛋白研究

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癌症 2006年第7期25卷 823-827页

作者：叶丽虹尤嘉琮郭威徐少峰吴莲英齐众张晓东南开大学生命科学学院教育部生物活性材料重点实验室天津300071 香港科技大学生化系

背景与目的:肿瘤转移相关蛋白在肿瘤细胞转移过程中具有重要作用,本研究在建立高转移潜能乳腺癌细胞株LM-MCF-7的基础上,筛选乳腺癌细胞转移相关蛋白并探讨其功能。方法:应用蛋白质组学和免疫印迹等方法比较和筛选来源相同但具有不同转... 详细信息

背景与目的:肿瘤转移相关蛋白在肿瘤细胞转移过程中具有重要作用,本研究在建立高转移潜能乳腺癌细胞株LM-MCF-7的基础上,筛选乳腺癌细胞转移相关蛋白并探讨其功能。方法:应用蛋白质组学和免疫印迹等方法比较和筛选来源相同但具有不同转移能力的乳腺癌细胞株(MCF-7/LM-MCF-7)的蛋白质表达差异。将克隆有存活蛋白(survivin)的真核表达载体pcDNA3-Sur转染至MCF-7细胞,通过“伤口愈合”实验检测存活蛋白对乳腺癌细胞迁移的影响。结果:应用蛋白质组学技术获得8个有意义的蛋白质,分别有参与细胞骨架构成、物质代谢、细胞凋亡、蛋白折叠和蛋白质相互作用等功能。应用免疫印迹方法发现,在MCF-7细胞中nm23、p27表达水平较高,在LM-MCF-7中存活蛋白、肌球蛋白轻链激酶(myosinlightchainkinase,MLCK)和Bcl-2表达水平较高。“伤口愈合”实验显示,存活蛋白过表达可明显增强MCF-7细胞的迁移能力。结论:不同转移能力的乳腺癌细胞株中存在与乳腺癌转移相关的蛋白质,存活蛋白与乳腺癌转移有密切的关系。

关键词：乳腺肿瘤肿瘤转移蛋白质组学肿瘤转移相关蛋白存活蛋白

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Applications of the Hilbert-Huang Transform for Microtremor Data Analysis Enhancement

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Journal of Earth Science 2015年第6期26卷 799-806页

作者： Lanbo Liu robert Mehl Weijun Wang qi-Fu Chen Department of Civil & Environmental Engineering University University of Connecticut Center for Integrative Geosciences University of Connecticut Institute of Earthquake Science China Earthquake Administration

In this paper we discuss the use of the Hilbert-Huang transform（HHT） to enhance the time-frequency analysis of microtremor measurements. HHT is a powerful algorithm that combines the process of empirical mode decomposition（EMD） and the Hilbert transform to compose the HilbertHuang spectrum that contains the time-frequency-energy information of the recorded signals. HHT is an adaptive algorithm and does not require the signals to be linear or stationary. HHT is advantageous for analyzing microtremor data, since observed microtremors are commonly contaminated by nonstationary transient noises close to the recording instruments. This is especially true when microtremors are measured in an urban environment. In our data processing HHT was used to（1） eliminate the unwanted short-duration transient constituents from microtremor data and use only the coherent portion of the data to carry out the widely used horizontal to vertical spectral ratio（H/V） method;（2） identify and eliminate the continuous industrial noise in certain frequency band; and（3） enhance the H/V analysis by using the Hilbert-Huang spectrum（HHS）. The efficacy of this proposed approach is demonstrated by the examples of applying it to microtremor data acquired in the metropolitan Beijing area.

关键词： Hilbert-Huang transform microtremor time-frequency HN engineering earthquake.

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Detection and Classification of Transmission Line Transient Faults Based on Graph Convolutional Neural Network

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 456-471页

作者： Houjie Tong robert C.qiu Dongxia Zhang Haosen Yang qi Ding Xin Shi Department of Electrical Engineering Center for Big Data and Artificial IntelligenceShanghai Jiao Tong UniversityShanghai 200240China School of Electronic Information and Communication Huazhong University of Science and TechnologyWuhan 430000China Electric Power Research Institute Haidian DistrictBeijing 100192China School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China

We present a novel transient fault detection and classification approach in power transmission lines based on graph convolutional neural *** with the existing techniques,the proposed approach considers explicit spatial information in sampling sequences as prior knowledge and it has stronger feature extraction *** this basis,a framework for transient fault detection and classification is *** structure is generated to provide topology information to the *** approach takes the adjacency matrix of topology graph and the bus voltage signals during a sampling period after transient faults as inputs,and outputs the predicted classification results ***,the proposed approach is tested in various situations and its generalization ability is verified by experimental *** results show that the proposed approach can detect and classify transient faults more effectively than the existing techniques,and it is practical for online transmission line protection for its rapidness,high robustness and generalization ability.

关键词： Graph convolutional network(GCN) power transmission line fault detection and classification spatio-temporal data topology information

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Hypocrellin A-based photodynamic action induces apoptosis in A549 cells through ROS-mediated mitochondrial signaling pathway

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Acta Pharmaceutica Sinica B 2019年第2期9卷 279-293页

作者： Shanshan qi Lingyuan Guo Shuzhen Yan robert J.Lee Shuqin Yu Shuanglin Chen Jiangsu Province Key Laboratory for Microbes and Functional Genomics College of Life SciencesNanjing Normal University College of Pharmacy the Ohio State University Cancer Pharmacology Crown Bioscience Inc. Jiangsu Province Key Laboratory for Molecular and Medical Biotechnology College of Life SciencesNanjing Normal University

Over recent decades, many studies have reported that hypocrellin A(HA) can eliminate cancer cells with proper irradiation in several cancer cell lines. However, the precise molecular mechanism underlying its anticancer effect has not been fully defined. HA-mediated cytotoxicity and apoptosis in human lung adenocarcinoma A549 cells were evaluated after photodynamic therapy(PDT). A temporal quantitative proteomics approach by isobaric tag for relative and absolute quantitation(iTRAQ) 2 D liquid chromatography with tandem mass spectrometric(LC–MS/MS) was introduced to help clarify molecular cytotoxic mechanisms and identify candidate targets of HA-induced apoptotic cell death. Specific caspaseinhibitors were used to further elucidate the molecular pathway underlying apoptosis in PDT-treated A549 cells. Finally, down-stream apoptosis-related protein was evaluated. Apoptosis induced by HA was associated with cell shrinkage, externalization of cell membrane phosphatidylserine, DNA fragmentation,and mitochondrial disruption, which were preceded by increased intracellular reactive oxygen species(ROS) generations. Further studies showed that PDT treatment with 0.08 mmol/L HA resulted in mitochondrial disruption, pronounced release of cytochrome c, and activation of caspase-3,-9, ***, HA may be a possible therapeutic agent directed toward mitochondria and a promising photodynamic anticancer candidate for further evaluation.

关键词： Hypocrellin A Photodynamic therapy Reactive oxygen species Proteomic LC–MS/MS iTRAQ

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Genome-wide association analysis reveals regulation of at-risk loci by DNA methylation in prostate cancer

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Asian Journal of Andrology 2021年第5期23卷 472-478页

作者： qiang Liu Gang Liu Darryl T Martin Yu-Tong Xing robert M Weiss Jun qi Jian Kang Department of Urology Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Urology Yale University School of MedicineNew HavenCT 06510USA Key Lab of Systems Biology Shanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China Institute of Estuarine and Coastal Research East China Normal UniversityShanghai 20CXD62China

Epigenetic changes are potentially important for the ontogeny and progression of tumors but are not usually studied because of the complexity of analyzing transcript regulation resulting from epigenetic *** cancer(PCa)is characterized by variable clinical manifestations and frequently unpredictable *** performed an expression quantitative trait loci(eQTL)analysis to identify the genomic regions that regulate gene expression in PCa and identified a relationship between DNA methylation and clinical *** multi-level information published in The Cancer Genome Atlas,we performed eQTL-based analyses on DNA methylation and gene *** better interpret these data,we correlated loci and clinical indexes to identify the important loci for both PCa development and *** data demonstrated that although only a small proportion of genes are regulated via DNA methylation in PCa,these genes are enriched in important cancer-related *** addition,single nucleotide polymorphism analysis identified the locations of CpG sites and genes within at-risk loci,including the 19q13.2-q13.43 and 16q22.2-q23.1 ***,an epigenetic association study of clinical indexes detected risk loci and pyrosequencing for site *** DNA methylation-regulated genes across PCa samples are a small proportion,the associated genes play important roles in PCa carcinogenesis.

关键词： CpG sites DNA methylation expression quantitative trait loci genome-wide association study prostate cancer

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The First Global Map of Atmospheric Ammonia(NH_(3)) as Observed by the HIRAS/FY-3D Satellite

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Advances in Atmospheric Sciences 2024年第3期41卷 379-390页

作者： Minqiang ZHOU Zhili DENG Charles robert Xingying ZHANG Lu ZHANG Yapeng WANG Chengli qi Pucai WANG Martine De MAZIÈRE Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Royal Belgian Institute for Space Aeronomy(BIRA-IASB) Brussels 1180Belgium National Satellite Meteorology Center China Meteorological AdministrationBeijing 100081China Department of Science&Technology and Climate Change China Meteorological AdministrationBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China

Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentration based on the absorption lines of NH_(3) in the thermal infrared region. In this study, we establish a retrieval algorithm to derive the NH_(3)column from the Hyperspectral Infrared Atmospheric Sounder(HIRAS) onboard the Chinese Feng Yun(FY)-3D satellite and present the first atmospheric NH_(3) column global map observed by the HIRAS instrument. The HIRAS observations can well capture NH_(3) hotspots around the world, e.g., India, West Africa, and East China, where large NH_(3) emissions exist. The HIRAS NH_(3) columns are also compared to the space-based Infrared Atmospheric Sounding Interferometer(IASI)measurements, and we find that the two instruments observe a consistent NH_(3) global distribution, with correlation coefficient(R) values of 0.28–0.73. Finally, some remaining issues about the HIRAS NH_(3) retrieval are discussed.

关键词： ammonia HIRAS/FY-3D satellite thermal-infrared observation remote sensing optimal estimation method

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LIQUID CRYSTAL POLYMERS WITH TWO-DIMENSIONAL MESOGENIC UNITS

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Chinese Chemical Letters 1991年第8期2卷 659-660页

作者： qi Feng ZHOU Zhi Cai robert W.LENZ Chemistry Department Peking UniversityBeijing 100871 Polymer Science&Engineering University of MassschusettsAmherstMA 01003USA

A series of 'liquid crystal polymers with two-dimensional mesogeuic units' were synthesized by the polycondensations of the monomer 2, 5-dihydroxybenzylidene-4-phenetidine with a diacid chloride selected from a series of α, ω-bis(4-chloroformylphenyloxy)carbonylalkues. This is the first series of polymers reported under the newly proposed concept 'liquid crystal polymers with two dimensional mesogenic units'.

关键词： LIQUID CRYSTAL POLYMERS WITH TWO-DIMENSIONAL MESOGENIC UNITS

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