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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

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Single-cell omics: experimental workflow, data analyses and applications

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Science China Life Sciences 2025年第1期68卷 5-102页

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu Fu Lei Gu Xin Shao Qinqin Wang Xin Dong Bin Duan Feiyang Xing jun Wu Minmin Xiao Fangqing Zhao Jing-Dong J.Han Qi liu Xiaohui Fan Chen Li Chenfei Wang Tieliu Shi Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of EducationOrthopaedic DepartmentTongji HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public HealthShanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang University Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesCenter for Quantitative Biology (CQB)Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women's HospitalZhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of StatisticsEast China Normal University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial sc RNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词： single-cell sequencing genome epigenome proteomics metabolomics multimodal spatial transcriptomics CRISPR screening

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注射吸毒者HCV单一感染和HIV/HCV共感染早期促进T细胞免疫衰老的研究

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中国药物依赖性杂志 2017年第3期26卷 182-188,194页

作者：鲁春霞郑澜张军刘羿丁杨后文其湖南师范大学体育学院长沙410081 湖南省戒毒管理局长沙410001

目的:了解注射静脉吸毒者(IDU)丙型肝炎病毒(HCV)单一感染和人类免疫缺陷病毒(HIV)/HCV共感染的关系,探讨其早期促进T细胞免疫衰老的严重程度。方法:调查有静脉注射吸毒史的人群在HCV单一感染和HIV/HCV合并感染时免疫参数的变化。T细胞... 详细信息

目的:了解注射静脉吸毒者(IDU)丙型肝炎病毒(HCV)单一感染和人类免疫缺陷病毒(HIV)/HCV共感染的关系,探讨其早期促进T细胞免疫衰老的严重程度。方法:调查有静脉注射吸毒史的人群在HCV单一感染和HIV/HCV合并感染时免疫参数的变化。T细胞亚群中端粒长度使用Flow-FISH测量。分析指标包括IDU患者HCV单感染(n=21)、HIV/HCV合并感染(n=23)或多次暴露但未感染(MEU)(n=8)的T细胞上的分化、凋亡标志物和端粒长度在基线t=1和t=2随访中测得的数据时间中位数间隔16.9年的变化,所有数据使用SPSS(SPSS 20.0)统计软件。结果:t=1和t=2之间的中值时间间隔为16.9年。在所有IDU组中,CD4^+和CD8^+T细胞内的端粒长度随时间显著降低(P≤0.012)。在t=1时HCV单纯感染的IDU CD4^+T细胞端粒长度与健康供体的相比显著减少(P<0.008)。HIV/HCV合并的IDU在t=1时CD4^+和CD8^+T细胞端粒长度也比健康供体减少(P≤0.002)。在CD4^+和CD8^+T细胞中,未成熟细胞与成熟、成熟分化细胞相比具有更长的RTL(P<0.001),成熟和成熟分化的细胞具有相似的RTL,表明它们经历可比较的增殖循环,所有T细胞亚群中观察到端粒长度减少,但主要在未成熟T细胞(CD27^+CD57^+)中发现的(P≤0.015)。程序性死亡因子1(PD-1)的表达水平,是慢性病毒疾病的衰竭的标志物和急性感染后的激活标志物。结论:HCV单一感染和HIV/HCV合并感染会促进T细胞免疫系统衰老且数据表明这发生在感染早期,所以HCV和HIV的早期治疗就对减缓免疫系统衰老尤为重要。

关键词：注射吸毒者免疫衰老 HCV HIV

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Agglomerated Pd Catalysts and Their Applications in Hydrogen Production from Formic Acid Decomposition at Room Temperature

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Chemical Research in Chinese Universities 2016年第2期32卷 272-277页

作者： liu jun lan Lixin WU Chao LI Rong liu Xuanyan Department of Pharmaceutical and Biological Engineering Hunan Chemical Vocational Technology College Zhuzhou 412004 P. R. China

Agglomerated Pd catalysts with the nano-porous structure were simply prepared by one-step reduction reaction without using any stabilizer. The Pd catalysts show a high catalytic activity for the decomposition of formic acid at room temperature. Among all the Pd catalysts tested, the Pdug catalyst exhibits the highest catalytic activity. Moreover, the breakthrough of the advanced catalysts is that the above agglomerated Pd catalysts can be easily separated from the liquid system to control the catalytic reaction at any time, which may further promote the practical application of formic acid as a H2 storage material.

关键词： Hydrogen energy Heterogeneous catalyst Formic acid decomposition Pd catalyst Nano-porous structure

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基于超高效液相色谱-质谱法脂质组学分析油莎草3个生长时期及组织脂类物质组成

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食品科学 2025年第3期46卷 146-161页

作者：杨雅萱卞苗苗刘艳庆刘军邢军涂亦娴新疆大学生命科学与技术学院新疆乌鲁木齐830017 新疆大学生命科学与技术学院新疆生物资源基因工程重点实验室新疆乌鲁木齐830017

为了深入探究油莎草不同生长时间不同组织的脂质组成、脂质动态变化,本研究基于超高效液相色谱-质谱法非靶向脂质组学对油莎草3个不同生长时期(70、93、120 d)地上茎、块茎、根中的脂类代谢物进行相对定量分析。结果显示,从油莎草上述... 详细信息

为了深入探究油莎草不同生长时间不同组织的脂质组成、脂质动态变化,本研究基于超高效液相色谱-质谱法非靶向脂质组学对油莎草3个不同生长时期(70、93、120 d)地上茎、块茎、根中的脂类代谢物进行相对定量分析。结果显示,从油莎草上述组织中共鉴定出16 904种脂类代谢物,筛选出720个脂类差异代谢物,其中油莎草块茎差异脂类物质含量显著高于地上茎和根,油莎草在生长过程中积累的脂质主要为甘油脂且大部分以甘油三酯的形式存在,油莎草3种组织的脂肪酸(fatty acid,FA)中不饱和脂肪酸的相对含量较高,均超过57.3%,块茎中不饱和脂肪酸FA(18:1)和FA(18:2)的含量较高。本研究从脂质代谢层面分析了油莎草不同生长时期不同组织的脂质差异代谢物、脂质组成及变化,可为其在食品加工和产品开发等领域的应用提供基础数据和科学依据。

关键词：油莎草脂质组学块茎超高效液相色谱-质谱脂肪酸

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Solving the Multi-discrete Logarithm Problems over a Group of Elliptic Curves with Prime Order

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1443-1450页

作者： jun Quan LI Mu lan liu Liang Liang XIAO Academy of Mathematics and Systems Science Key Laboratory of Mathematics Mechanization Chinese Academy of Sciences Beijing 100080 P. R. China

In this paper, we discuss the expected number of steps in solving multi-discrete logarithm problems over a group of elliptic curves with prime order by using Pollard＇s rho method and parallel collision search algorithm. We prove that when using these algorithms to compute discrete logarithms, the knowledge gained through computing many logarithms does not make it easier for finding other logarithms. Hence in an elliptic cryptosystem, it is safe for many users to share the same curve, with different private keys.

关键词： Pollard's rho method Parallel collision search algorithm Elliptic curve Discrete logarithm Distinguished point

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi liu Yan-Bo Li Qi Zhang jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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A VO_(2) film-based multifunctional metasurface in the terahertz band

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Chinese Optics Letters 2022年第1期20卷 167-173页

作者： Ziyu liu Limei Qi Feng lan Chuwen lan jun Yang Xiang Tao School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Collaborative Innovation Center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China The Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Shenzhen Research Institute Beijing University of Posts and TelecommunicationsShenzhen 518000China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

We proposed a multifunctional terahertz metasurface based on a double L-shaped pattern and a vanadium dioxide(VO_(2)) film separated by *** the VO_(2)film is an insulator,a dual-band electromagnetically induced transparency effect is obtained,and the physical mechanism is investigated based on the current distribution and "two-particle" *** the VO_(2)film is a metal,a dual-band linear-to-circular polarization converter,in which the y-polarized linear wave can be effectively converted to left-handed circularly polarized(LCP) and right-handed circularly polarized simultaneously in different bands,can be *** arranging the metal pattern rotating 30°,a multifunctional antenna can be *** the VO_(2)is an insulator,the radiation of the LCP wave is divided into four beams,with two beams reflected and two beams *** the VO_(2)is in the metallic state,we can only get the co-polarized reflected wave with a 21° ***,in our design,the VO_(2)film does not need lithography to obtain certain patterns,which improves the convenience of fabrication and *** design opens a new way for the development of multifunctional terahertz devices and has potential applications in the terahertz communication field.

关键词： terahertz VO_(2) antenna metasurface

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Thermal transport in organic/inorganic composites

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Frontiers in Energy 2018年第1期12卷 72-86页

作者： Bin liu lan DONG Qing Xi Xiangfan XU jun ZHOU Baowen LI Center for Phononics and Thermal Energy Science China-EU JointCenter for Nanophononics Shanghai Key Laboratory of SpecialArtificial Microstructure Materials and Technology School of PhysicsScience and Engineering Tongji University Shanghai 200092 China Department of Mechanical Engineering University of ColoradoBoulder CO 80309 USA

Composite materials, which consist of organic and inorganic components, are widely used in various fields because of their excellent mechanical properties, resistance to corrosion, low-cost fabrication, etc. Thermal properties of organic/inorganic composites play a crucial role in some applications such as thermal interface materials for micro-electronic packaging, nano-porous materials for sensor development, thermal insulators for aerospace, and high-performance thermoelectric materials for power generation and refrigeration. In the past few years, many studies have been conducted to reveal the physical mechanism of thermal transport in organic/ inorganic composite materials in order to stimulate their practical applications. In this paper, the theoretical and experimental progresses in this field are reviewed. Besides, main factors affecting the thermal conductivity of organic/ inorganic compositcs are discussed, including the intrinsic properties of organic matrix and inorganic fillers, topolo- gical structure of composites, loading volume fraction, and the interfacial thermal resistance between fillers and organic matrix.

关键词： thermal conductivity organic/inorganic com-posites effective medium theory thermal percolationtheory interfacial thermal resistance

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In vitro evaluation of degradation,cytocompatibility and antibacterial property of polycaprolactone/hydroxyapatite composite coating on bioresorbable magnesium alloy

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Journal of Magnesium and Alloys 2022年第8期10卷 2252-2265页

作者： Zhang Chunyan Cheng lan Lin Jiajia Sun Dongwei Zhang jun liu Huinan School of Materials Science&Engineering Chongqing University of TechnologyNo.69 Hongguang AvenueChongqing 400054China Department of Bioengineering and the Materials Science and Engineering ProgramUniversity of CaliforniaRiverside900 University AvenueMSE 205RiversideCA 92521USA

Polycaprolactone/hydroxyapatite(PCL/HA)composite coating was fabricated by a combination of hydrothermal and dipping methods to delay the degradation of Mg alloy AZ31 as bioresorbable *** PCL/HA coating was composed of nano rod-shape HA crystals and PCL filled in the space of HA *** with the single HA coating,the binding strength between the PCL/HA composite coating and Mg alloy was obviously improved and the PCL/HA coating still adhered to the surface of AZ31 substrate even after 38 days of *** electrochemical corrosion rate of HA coated sample was reduced by ten times after being filled by *** electrochemical impedance spectroscopy(EIS)and immersion test results showed that the PCL/HA composite coating could provide a more effective barrier for Mg substrate than the HA coating *** cytocompatibility and the antibacterial property of HA coating and PCL/HA coating were evaluated by culturing with bone marrow-derived mesenchymal stem cells(BMSCs)and methicillin-resistant staphylococcus aureus(MRSA)for 24 h under direct culture conditions,*** PCL/HA composite coating showed better BMSC cell compatibility,more suitable for BMSC adhesion than HA coating alone and showed a potential application prospect as a biological ***,from the perspective of clinical applications,the antibacterial property of PCL/HA composite coating needs to be further improved.

关键词： Mg alloy PCL/HA coating Corrosion resistance Cytocompatibility Antibacterial property

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