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Purification, Biological Activities, and Molecular Cloning of a Novel Mannose-Binding Lectin from Bulbs of Zephyranthes candida Herb （Amaryllidaceae）

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Journal of Integrative Plant Biology 2006年第2期48卷 223-231页

作者： Chuan-Fang Wu Jian Li Jie An Li-Qing Chang Fang Chen jin-ku bao College of Life Sciences Sichuan University Chengdu 610064 China

A novel mannose-bindlng aggiutinln was purified from bulbs of Zephyranthes candida Herb by extraction, precipitation with 80% （NH4）2SO4, and ion-exchange chromatography on DEAE-Sepharose followed by gel flitration on Sephscryl S-100. The purified Z. candida agglutlnln （ZCA） migrated as a single band of 12 kDa on sodium dodecyi suifate-poiyecryiamide gel electrophoresis under reducing and non-reducing conditions. The apparent molecular mass of the iectln, as datermlned by gel filtration chromatography, was 48 kDa. The results Indicated that ZCA was composed of four Identical subunlts of 12 kDa each （homotetramerlc nature）. The ZCA agglutlhated rabbit erythrocytes, Escherichla coil and Saccharomyces cerevislae ceils at concentrations of 0.95, 1.90, and 31.30 μg/mL, respectively. Bloassays Indicated that ZCA has a significant effect on wheat aphid survival. Mortality after 7 d was 〉 90% at 0.26%. A degenerate primer was designed In accordance with the N-terminal partial sequence of purified ZCA. The full-length cDNA was cloned by 3＇- and 5＇-rapid amplification of cDNA ends. The full-length cDNA had 661 bp and the sequence encoded an open reading frame of 168 amino acids. The mature protein of ZCA Includes 109 amino acid residues and the molecular weight of the protein was 12.1 kDa. The result show that the zca gene encodes a protein precursor with a signal peptlde, a mature protein, and a C-terminal cleavage amino acids sequence. Molecular modeling of ZCA Indicated that Its three-dimensional atructure strongly resembies that of the snowdrop aggiutinin. Blocks＇ analysis revealed that the deduced amino acid sequence of ZCA has three functional domains specific for agglutination and three carbohydrate binding boxes （QDNY）.

关键词： agglutinating activity insecticidal activity molecular clone sequence analysis Zephyranthes candida agglutinin.

In silico identification of potential inhibitors targeting Streptococcus mutans sortase A

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International Journal of Oral Science 2017年第1期9卷 53-62页

作者： Hao Luo Dan-Feng Liang Min-Yue bao Rong Sun Yuan-Yuan Li Jian-Zong Li Xin Wang Kai-Min Lu jin-ku bao School of Life Sciences and Key Laboratory of Ministry of Education for Bio-Resources and Bio-Environment Sichuan University State Key Laboratory of Biotherapy/Collaborative Innovation Centre for Biotherapy West China HospitalSichuan University State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan University

Dental caries is one of the most common chronic diseases and is caused by acid fermentation of bacteria adhered to the teeth. Streptococcus mutans （S. mutans） utilizes sortase A （SrtA） to anchor surface proteins to the cell wall and forms a biofilm to facilitate its adhesion to the tooth surface. Some plant natural products, especially several flavonoids, are effective inhibitors of SrtA. However, given the limited number of inhibitors and the development of drug resistance, the discovery of new inhibitors is urgent. Here, the high-throughput virtual screening approach was performed to identify new potential inhibitors of S. mutans SrtA. Two libraries were used for screening, and nine compounds that had the lowest scores were chosen for further molecular dynamics simulation, binding free energy analysis and absorption, distribution, metabolism, excretion and toxicity （ADMET） properties analysis. The results revealed that several similar compounds composed of benzofuran, thiadiazole and pyrrole, which exhibited good affinities and appropriate pharmacokinetic In addition, the carbonyl of these compounds can have a strategy for microbial infection disease therapy. parameters, were potential inhibitors to impede the catalysis of SrtA. key role in the inhibition mechanism. These findings can provide a new

关键词： dental caries molecular dynamics simulation molecular docking potential inhibitors sortase A Streptococcus mutans

Effects of Denaturation and Amino Acid Modification on Fluorescence Spectrum and Hemagglutinating Activity of Hericium erinaceum Lectin

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 343-350页

作者： Meng GONG, Jie AN, Hong-Zhou Lü, Chuan-Fang WU, Yi-jin LI, jing-Qiu CHENG, and jin-ku bao*College of Life Sciences, Sichuan University, Chengdu 610064, China College of Life Sciences Sichuan University Chengdu 610064 China

A sialic acid-binding lectin (Hericium erinaceum lectin, HEL), isolated from fresh fruiting bodies of Hericium erinaceum, was treated with various temperature and pH to investigate its fluorescence spectra and hemagglutinating activity. It was found that the hemagglutinating activity of HEL was relatively steady below 60 °C and at pH from 6 to 11, and the change of hemagglutinating activity was relative to the change of hydrophobic areas where tryptophan residues located. In fluorescence quenching study of HEL by acrylamide and KI, it was indicated that nearly all the tryptophan residues of HEL located on the surface of the molecule, and most of them were in hydrophobic areas or negatively charged areas. Chemical modifica- tion of HEL proved that there were about twelve tryptophan residues in a HEL molecule and all of them were located on the surface or in the shallow groove of the molecule, and eight of them were essential for hemag- glutinating activity; aspartic acid or glutamic acid residues were involved in maintaining the crucial confor- mation of activity center and made great contribution to the hemagglutinating activity of HEL, but they could not touch the sialic acid molecule directly; tyrosine residues also played a role in the hemagglutinating activ- ity of HEL; while arginine, serine, threonine, histidine residues had no effect on the hemagglutinating activity of HEL.

关键词： sialic acid-binding lectin Hericium erinaceum lectin fluorescence spectrum and fluores- cence quenching hemagglutinating activity chemical modification

Effect of Amino Acid Residue and Oligosaccharide Chain Chemical Modifications on Spectral and Hemagglutinating Activity of Millettia dielsiana *** ***

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 47-54页

作者： Shun GAO Jie AN Chuan-Fang WU Ying GU Fang CHEN Yuan YU~1 Qia-Qing WU~* jin-ku bao~* College of Life Sciences.Sichuan Uiversity,Chengdu 610064.China ~1Chengdu Institute of Biology.Chinese Academy of Sciences.Chengdu 610041.China College of Life Sciences Sichuan UniversityChengdu 610064 China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041 China

The effects of modifying the carbohydrate chain and amino acids on the conformation andactivity of Millettia dielsiana *** ***（MDL）were studied by hemagglutination,fluorescenceand circular dichroism *** modification of tryptophan residues led to a compete loss of hemagglu-tinating activity;however,the addition of mannose was able to prevent this loss of *** resultsindicate that two tryptophan residues are involved in the carbohydrate-binding *** of thecarboxyl group residues produced an 80% loss of activity,but the presence of mannose protected against *** results suggest that the carboxyl groups of aspartic and glutamic acids are involved in thecarbohydrate-binding site of the ***,oxidation of the carbohydrate chain and modification of thehistidine and arginine residues did not affect the hemagglutinating activity of *** studies ofMDL indicate that tryptophan residues are present in a relatively hydrophobic region,and the binding ofmannose to MDL could quench tryptophan fluorescence without any change in λ*** circular dicbroismspectrum showed that all of these modifications affected the conformation of the MDL molecule to differentextents,except the modification of arginine *** quenching showed that acrylamide andiodoacetic acids are able to quench 77% and 98% of the fluorescence of tryptophan in MDL,***,K1 produced a barely perceptible effect on the fluorescence of MDL,even when the concentrationof I-was 0.15 *** demonstrates that most of tryptophan residues are located in relatively hydrophobicor negatively charged areas near the surface of the MDL molecule.

关键词： Millettia dielsiana Harms. ex Diels. lectin(MDL) chemical modification hemagglutinating activity circular dichroism fluorescence quenching

Intelligent casting:Empowering the future foundry industry

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China Foundry 2024年第5期21卷 409-426页

作者： jin-wu Kang bao-lin Liu Tao jing Hou-fa Shen School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts more and more attention from the academic and industry *** this paper,the main features of casting technology were briefly summarized and forecasted,and the recent developments of key technologies and the innovative efforts made in promoting intelligent casting process were ***,the technical visions of intelligent casting process were also put *** key technologies for intelligent casting process comprise 3D printing technologies,intelligent mold technologies and intelligent process control *** future,the intelligent mold that derived from mold with sensors,control devices and actuators will probably incorporate the Internet of Things,online inspection,embedded simulation,decision-making and control system,and other technologies to form intelligent cyber-physical casting system,which may pave the way to realize intelligent *** is promising that the intelligent casting process will eventually achieve the goal of real-time process optimization and full-scale control,with the defects,microstructure,performance,and service life of the fabricated castings can be accurately predicted and tailored.

关键词： intelligent casting 3D printing intelligent mold process control cyber-physical casting system embedded simulation

Stereoselective Self-Assembly of Chiral Metalla[2]Catenanes and Lemniscular Macrocycles

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CCS Chemistry 2024年第8期6卷 2000-2010页

作者： Shu-jin bao Hai-Ning Zhang Guo-Xin jin Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of PolymersDepartment of ChemistryFudan UniversityShanghai 200433

Designing and stereoselectively constructing chiral mechanically interlocked molecules(MIMs)is a goal that many chemists are pursuing due to their potential in the development of functional molecular machines involved in catalysis,sensing,and chiroptical ***,the synthesis of enantiopure supramolecular entities with crystallographic structures remains ***,the stereoselective self-assembly of chiral metalla[2]catenanes interlocked by two D-shaped macrocycles was realized by combining long binuclear half-sandwich organometallic Cp*Rh^(III)(Cp*=η^(5)-pentamethylcyclopentadienyl)clip and ditopic monodentate ligand incorporating L-leucine *** resulting metalla[2]catenane displayed unique co-conformational mechanical helical chirality characteristics arising from the chirality transfer of the chiral ***,decreasing the length of the binuclear Cp*Rh^(III)clip and adjusting the steric hindrance of the amino-acid side chains(L-alanine and L-phenylalanine)in the ligands resulted in two lemniscular macrocycles with left-handed(M)-twisted conformational *** the best of our knowledge,the synthesized macrocycles are the first family of homochiral abnormal lemniscate-shaped organometallic macrocycles featuring figure-eight ***[2]catenanes and macrocycles with opposite chirality were also generated by employing corresponding D-amino acid ligands,as evidenced by single-crystal X-ray diffraction,nuclear magnetic resonance,mass,and circular dichroism *** present study demonstrates that homochiral MIMs can be accessed readily using amino acid–containing ligands through rational molecular design.

关键词： stereoselective synthesis chirality metallacatenanes twisted macrocycles aminoacid residues

Insights into postural orthostatic tachycardia syndrome after COVID-19 in pediatric patients

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World Journal of Pediatrics 2024年第3期20卷 201-207页

作者： Ya-Xi Cui Jun-bao Du Hong-Fang jin Department of Pediatrics Peking University First HospitalNo.1 Xi-an Men StreetWest DistrictBeijing 100034China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijing 100191China

The pandemic caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)profoundly threatened human health globally and greatly impacted the world economy[1].While most patients recovered,some suff... 详细信息

关键词： acute patients tachycardia

Testing the first law of black hole mechanics with gravitational waves

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 76-82页

作者： Chao-Wan-Zhen Wang jin-bao Zhu Guo-Qing Huang Fu-Wen Shu Department of Physics Nanchang UniversityNanchang 330031China Center for Relativistic Astrophysics and High Energy Physics Nanchang UniversityNanchang 330031China GCAP-CASPER Physics DepartmentBaylor UniversityWaco 76798-7316USA

The successful observation of gravitational waves has provided humanity with an additional method to explore the universe,particularly black *** this study,we utilize data from LIGO and Virgo gravitational wave observations to test the first law of black hole mechanics,employing two different *** consider the secondary compact object as a perturbation to the primary black hole before the merger,and the remnant black hole as a stationary black hole after the *** the pre-merger and post-merger analysis,our results demonstrate consistency with the first law,with an error level of approximate 25%at a68%credibility level for *** the full inspiral-merger-ringdown analysis,our results show consistency with the first law of black hole mechanics,with an error level of about 6%at a 68%credibility level and 10%at a 95%credibility level for ***,we observe that the higher the mass ratio of the gravitational wave source,the more consistent our results are with the first law of black hole ***,our study sheds light on the nature of compact binary coalescence and their implications for black hole mechanics.

关键词： gravitational waves black hole mechanics data analysis ringdown

Incombustible solid polymer electrolytes:A critical review and perspective

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Journal of Energy Chemistry 2024年第6期93卷 264-281,I0007页

作者： Kai Wu jin Tan Zhenfang Liu Chenguang bao Ao Li Qi Liu baohua Li College of Materials Science and Engineering Hunan UniversityChangsha 413000HunanChina Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 055GuangdongChina

Since the advent of the solid-state batteries,employing solid polymer electrolytes(SPEs)to replace routine flammable liquid electrolytes is regarded to be one of the most promising solutions in pursing highenergy-density battery *** with superior thermal stability,good processability,and high mechanical modulus obtain increasing ***,SPE-based batteries are not impenetrable due to their decomposition and combustibility under extreme *** believe incorporating appropriate flame-retardant additives/solvents/fragments into SPEs can intrinsically reduce their flammability to solve the battery safety *** this review,the recent research progress of incombustible SPEs,with special emphasis on flame-retardant structural design,is ***,a brief introduction of flame-retardant mechanism,evaluation index for safety of SPEs,and a detailed overview of the latest advances on diverse-types SPEs in various battery systems are *** deep insight into thermal ru naway process,the free-standing incombustible GPEs,and the ratio nal design of pouch cell structures may be the main directions to motivate revolutionary next-generation for safety batteries.

关键词： Non-flammable electrolyte Solid polymer electrolyte High safety electrolyte Solid state electrolyte Solid state battery