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Trichloroethylene改变融合期内皮细胞一氧化氮和氧自由基的平衡(英文)

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中山大学学报：医学科学版 2004年第6期25卷 496-503页

作者：区景松欧志君 kirkwood a.pritchard jr 广州医学院第一附属医院广州医学院第一附属医院心内科 Division of Pediatric Surgery Departments of Surgery Pharmacology and Toxicology Cardiovascular Center and Free Radical Research Center Medical College of Wisconsin MilwaukeeWisconsin 53226 USA

【目的】Trichloroethylene(TRI)是一种与先天性心脏病发生有关的环境污染物,我们最近报道在分裂期的内皮细胞(EC)中,TRI可以通过减少热休克蛋白90(hsp90)与内皮一氧化氮合酶(eNOS)结合,从而抑制刺激状态下一氧化氮(NO)产生和增加刺激... 详细信息

【目的】Trichloroethylene(TRI)是一种与先天性心脏病发生有关的环境污染物,我们最近报道在分裂期的内皮细胞(EC)中,TRI可以通过减少热休克蛋白90(hsp90)与内皮一氧化氮合酶(eNOS)结合,从而抑制刺激状态下一氧化氮(NO)产生和增加刺激状态下eNOS依赖的超氧阴离子自由基()产生和抑制血管内皮生长因子刺激的内皮细胞分裂。但TRI在融合期EC中的影响仍未清楚。本实验目的是探讨TRI对融合期EC的影响。【方法】TRI5μmol/L预处理融合期EC,用钙离子导体A231875μmol/L刺激,然后,检测NO与的产生以了解EC和eNOS的功能情况。用免疫印迹方法检查eNOS,位点于丝氨酸1179的磷酸化eNOS,与eNOS结合的hsp90水平来决定eNOS的激活状态。【结果】TRI减少A23187刺激状态下亚硝酸盐和硝酸盐的产生从(1.16±0.15)nmol·mg-1到(0.91±0.3)nmol·mg-1(P<0.05);在对照情况下,L-NAME增加A23187刺激状态下的产生从(0.015±0.007)nmol/(min·mg)到(0.044±0.008)nmol/(min·mg)(P<0.05);在TRI处理的培养中,L-NAME减少A23187刺激状态下的产生从(0.057±0.022)nmol/(min·mg)到(0.039±0.005)nmol/(min·mg)(P<0.05),并且oxypurinol减少A23187刺激状态下的产生从(0.057±0.022)nmol/(min·mg)到(0.034±0.012)nmol/(min·mg)(P<0.05);

关键词： NOS hsp90 EC L-NAME 热休克蛋白90 一氧化氮合酶一氧化氮氧自由基内皮细胞

L-4F明显改善脂蛋白氧化张力下的血管舒张功能

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中华心血管病杂志 2004年第10期32卷 911-914页

作者：区景松欧志君 Deron W.Jones kirkwood a.pritchard jr 广州医学院第一附属医院广州呼吸疾病研究所心胸外科广州医学院第一附属医院心内科 Pediatric Surgery Cardiovascular CenterMedical College of WisconsinMilwaukeeWI53226United States

目的　　探讨L 4F(一种载脂蛋白A 1类似物 )能否改善脂蛋白氧化张力下内皮依赖的血管舒张功能。方法　实验分三部分 ,均采用小鼠的颈内动脉作乙酰胆碱诱导下的内皮依赖血管舒张功能试验。第一部分采用C5 7BL6小鼠 ,分 2组 :对照组用PBS... 详细信息

目的　　探讨L 4F(一种载脂蛋白A 1类似物 )能否改善脂蛋白氧化张力下内皮依赖的血管舒张功能。方法　实验分三部分 ,均采用小鼠的颈内动脉作乙酰胆碱诱导下的内皮依赖血管舒张功能试验。第一部分采用C5 7BL6小鼠 ,分 2组 :对照组用PBS液 1L/L、L 4F组用L 4F 10mg/L预处理血管 30min。第二部分采用C5 7BL6小鼠 ,分 3组 ,对照组用RPMI 16 4 0培养液 10 0ml/L、低密度脂蛋白 (lowdensitylipoprotein ,LDL)组用LDL 10 0mg/L、LDL +L 4F组用LDL 10 0mg/L +L 4F 1mg/L预处理血管 30min。第三部分分 3组 ,对照组采用C5 7BL6小鼠 ,不作处理 ,高胆固醇血症组和L 4F组均采用低密度脂蛋白受体缺乏小鼠 ,用高脂、高胆固醇喂养 4周 ,其中高胆固醇血症组同时用生理盐水 10ml·kg-1·d-1腹膜腔内注射 (L 4F组用L 4F 1mg·kg-1·d-1)。结果　 (1)L 4F本身对内皮依赖的血管舒张功能没有影响 ;(2 )L 4F可以部分改善低密度脂蛋白对内皮依赖的血管舒张功能的抑制 ;(3)L 4F可以明显改善高胆固醇血症对内皮依赖的血管舒张功能的损害 ,达到与对照组的血管舒张功能无区别。结论　L 4F可明显改善脂蛋白氧化张力下内皮依赖的血管舒张功能。

关键词：血管舒张功能内皮依赖对照组小鼠高胆固醇血症载脂蛋白A LDL BL 腹膜腔类似物

Angiostatin损伤内皮细胞功能的机制

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中国心血管病研究 2005年第5期3卷 372-375页

作者：区景松 kirkwood a.pritchard jr 广州医学院第一附属医院广州呼吸疾病研究所心胸外科 Pediatric Surgery Cardiovascular CenterMedical College of W isconsinUSA

目的Angiostatin(AS)是一种具有抑制血管生成和抗肿瘤作用的物质。本实验探讨AS损伤内皮功能的机理。方法采用牛主动脉内皮细胞(***)做细胞培养,用AS120nmol/L孵育BAEC15min,然后①用氯化钒Ⅲ臭氧化学发光法测量一氧化氮(NitricOxide,NO... 详细信息

目的Angiostatin(AS)是一种具有抑制血管生成和抗肿瘤作用的物质。本实验探讨AS损伤内皮功能的机理。方法采用牛主动脉内皮细胞(***)做细胞培养,用AS120nmol/L孵育BAEC15min,然后①用氯化钒Ⅲ臭氧化学发光法测量一氧化氮(NitricOxide,NO)的产量;②用超氧化物歧化酶可抑制的铁化细胞色素C还原法测量氧自由基(SuperoxideAnion,O·2-)的产量;③用Western印迹和免疫沉淀法测量磷酸化内皮一氧化氮合酶(phosphorylationofendothelialnitricoxidesynthase.P-eNOS)、内皮一氧化氮合酶(***)、热休克蛋白90(heatshockprotein90,hsp90)的表达及eNOS与hsp90结合情况。结果AS可抑制BAECNO的产生,而增加eNOS来源的O2·-产生,对P-eNOS,eNOS和hsp90的表达无影响,但可减少hsp90与eNOS的结合。结论AS可以阻止hsp90与eNOS结合,使eNOS非偶联,破坏NO与O·2-的平衡,从而损伤内皮细胞功能,这可能是AS抗血管生成和抗肿瘤作用的机理,为将来AS应用于临床提供理论依据。

关键词：热休克蛋白90 内皮内皮一氧化氮合酶一氧化氮氧自由基

L-4F抑制低密度脂蛋白对热休克蛋白90的影响

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中国心血管病研究 2005年第2期3卷 142-145页

作者：欧志君区景松马虹苏诚坚 kirkwood a.pritchard jr 广州医学院第一附属医院心内科广东省广州市510120 广州医学院第一附属医院中山大学附属第一医院心内科 Pediatric Surgery Cardiovascular CenterMedical College of WisconsinUSA

目的探讨L-4F(一载脂蛋白A-I类似物)能否抑制低密度脂蛋白(lowdensitylipoprotein,LDL)对热休克蛋白90(heatshockprotein90,hsp90)与内皮一氧化氮合酶(endothelialnitricoxidesynthase,eNOS)结合的影响和LDL诱导的脂质氢过氧化物产生的增加。方法采用牛主动脉内皮细胞(bovineaorticendothelialcells,BAEC)进行细胞培养,用LDL6.2mmol/L和/或L-4F10μg/ml处理细胞24小时,然后,①分对照、L-4F、A23187(钙离子导体)、L-4F+A23187、LDL、LDL+L-4F、LDL+A23187、LDL+A23187+L-4F8组,用免疫沉淀法测定磷酸化内皮一氧化氮合酶(phosphorylationofeNOS,P-eNOS)、eNOS和hsp90的表达和结合情况;②用Auerbach法测定有BAEC和无BAEC情况下LDL诱导的脂质氢过氧化物的产生情况。结果①LDL减少A23187刺激状态下的BAEC的hsp90与eNOS的结合,而经L-4F预处理的LDL对hsp90与eNOS结合无抑制作用;②在无BAEC情况下,L-4F稍微抑制LDL诱导的脂质氢过氧化物的产生,然而在BAEC培养情况下,L-4F可以明显抑制LDL诱导的脂质氢过氧化物的产生。结论L-4F可以阻止LDL对hsp90与eNOS结合的抑制,并可能与L-4F抑制脂质氢过氧化物的产生有关,这可能是L-4F保护内皮细胞功能、抑制动脉粥样硬化形成的一个重要机制。

关键词：脂蛋白类热休克蛋白90 内皮一氧化氮合酶脂质氢过氧化物

From the dust:extracellular vesicles as regulators of development and neuroregeneration

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Neural Regeneration Research 2024年第5期19卷 933-934页

作者： Leon G.Coleman jr The University of North Carolina at Chapel Hill School of MedicineDepartment of PharmacologyBowles Center for Alcohol StudiesChapel HillNCUSA

First impressions can have a lasting *** science,this can be especially problematic,because our lack of understanding often causes us to mislabel and thus ignore important biological *** this vein,extracellular vesicles(EVs)were once considered to be“cellular dust”.Similar to the previous concept of“junk DNA”to describe protein non-coding regions,EVs are far more than just cellular *** fact,EVs are emerging as key mediators of intracellular communication across nearly all biological *** includes peripheral immune responses(e.g.,arthropathies and sepsis),intra-organ communication(Seim et al.,2023),and a host of other physiological and pathological states(Figure 1A and B).

关键词： Figure extracellular

Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang Yang Liang Julius Rebek jr. Yang Yu Center for Supramolecular Chemistry&Catalysis and Department of Chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction ***,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and *** containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the *** this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular *** container compounds include carcerands,deep cavitands and amide *** focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,O-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

Enhancement of mechanical properties of GTAW joints for ZC63 magnesium alloy by post-weld heat treatment

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Journal of Materials Science & Technology 2024年第2期169卷 251-263页

作者： Weiyang Zhou Qichi Le Ye Shi Qiyu Liao Tong Wang Qi Zou Clodualdo Aranas jr Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Department of Mechanical Engineering University of New BrunswickFrederictonE3B 5A3New BrunswickCanada

To further improve the microstructure and mechanical properties of gas tungsten arc welded(GTAW)welded joints for ZC63 magnesium alloy,post-weld heat treatment is carried *** is found that the majority of the MgZnCu phase in the fusion zone(FZ)is dissolved in theα-Mg matrix under suitable heat treatment *** remainder is diffusely distributed as rods or granules at the grain *** excessive heat treatment temperature(460℃)leads to abnormal grain growth(AGG)in the *** substructure gradient between the abnormally grown grains and the surrounding small grains pro-vides the driving force for ***,the dissolution of the MgZnCu phase weakens the hindering effect of the second phase on grain boundary migration,setting the stage for *** addition,the detri-mental impact of the continuous MgZnCu phase on the mechanical properties of the welded joint is also lessened by its *** ultimate tensile strength(UTS),yield strength(YS)and elongation(EL)of the welded joints are 255 MPa,119 MPa and 27.0%,respectively,under the post-weld heat treatment process of 440℃×12 *** welding coefficient of the welded joint reaches 97.0%,satisfying the service criteria set forth by the mechanical properties of the welded joints.

关键词： GTAW FZ Heat treatment AGG Mechanical properties

SnRK1a1, a new player in the sucrose-Opaque2 network during endosperm filling

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Molecular Plant 2024年第8期17卷 1172-1174页

作者： Kelly Mayrink Balmant Marcio F.R.Resende jr. Horticultural Sciences Department University of FloridaGainesvilleFLUSA

Maize(Zea mays)endosperm is an important food source for humans and *** addition,it is considered an excellent model for research on seed development because of its relatively large size for both embryo and endosperm compared to those of other crop species,such as rice(Oryza sativa)and wheat(Triticum aestivum).After double fertilization,early maize endosperm development includes three stages:(i)a multinucleate coenocyte stage;(i)a cellularization stage,in which the cellular endosperm is formed;and(ii)a stage of differentiation into distinct *** early differentiation,four major cell types with specific functions differentiate within the endosperm:starchy endosperm,aleurone layer,basal endosperm transfer layer(BETL),and embryo surrounding *** subaleurone,conducting zone,basal intermediate zone,and endosperm adjacent to scutellum arise in late differentiation(Sabelli and Larkins 2009).After the main cell types are established,maize endosperm undergoes intensive cell proliferation,which marks the transition to the endosperm-filling *** the endosperm-flling stage,the maternal sucrose products are transported to seeds through the BETL region,where they will act as the main carbon substrate for storage products such as starch and proteins(Chen et al.,2023).In fact,the endosperm of maize seeds accounts for approximately 90%of the total grain weight,serving as an important nutrient reservoir(Flint-Garcia et al.,2009).

关键词： endosperm reservoir Flint

Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1322-1332页

作者： Qinghe Cui Xuefeng Liu Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik jr. Dzmitry Bahrets Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Institute of Technical Acoustics National Academy of SciencesVitebsk 210009Belarus

Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the *** technology has a very broad application prospect in industrial *** have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this *** this review,metals were classified according to their crystal *** effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were *** main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed.

关键词： ultrasonic vibration plastic forming crystal structure microstructure forming mechanism