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中华少年.DK百科.少年版 2011年第9期 38-41页

作者：昕玥

人类对两个问题一直很感兴趣：①是什么决定了生物的特性？②这种特性是如何代代相传的？dna的发现和遗传学是20世纪最伟大的成就之一。

关键词： dna 科学家信息载体染色体

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dna

小学生时代 2005年第2期 32-33页

作者：王晓明罗妍

FTA-环介导等温扩增技术直接提取变异链球菌dna的效果评价

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中国组织工程研究 2025年第5期29卷 1043-1049页

作者：王玥晖尚进杨晨符冬格曹灿张晓东王敬夫北部战区总医院口腔科辽宁省沈阳市110016 空军军医大学第三附属医院颌面外科陕西省西安市710004

背景:变异链球菌是龋病的重要病原菌,及时检测变异链球菌水平对龋病的早发现、早治疗有重要意义。目的:建立并评价FTA-环介导等温扩增(loop-mediated isothermal amplification,LAMP)技术直接提取变异链球菌dna的应用效果。方法:①制备... 详细信息

背景:变异链球菌是龋病的重要病原菌,及时检测变异链球菌水平对龋病的早发现、早治疗有重要意义。目的:建立并评价FTA-环介导等温扩增(loop-mediated isothermal amplification,LAMP)技术直接提取变异链球菌dna的应用效果。方法:①制备含有ATCC标准菌株变异链球菌的菌悬液,接种于脑心浸出液培养基,充分混匀后按10倍梯度稀释成7种浓度(4.2×10^(7),4.2×10^(6),4.2×10^(5),4.2×10^(4),4.2×10^(3),4.2×10^(2),4.2×10 CFU/mL),每个稀释级做2个平行对照,并增加无菌水作为空白对照;②分别采用FTA卡、常规煮沸法、试剂盒提取及裂解液提取4种方法直接提取菌株dna,通过LAMP技术进行扩增,并进行特异性试验,比较4种提取方法的差异。结果与结论:①4种方法提取的dna均满足LAMP扩增的要求;②特异性试验结果显示,只有变异链球菌才可特异扩增出靶基因;③裂解液提取法最低检测限为4.2×10^(3) CFU/mL,FTA卡提取法最低检测限为4.2×10^(4) CFU/mL,试剂盒提取法和常规煮沸法最低检测限分别为4.2×10^(6) CFU/mL和4.2×10^(7) CFU/mL;④4种提取方法其他方面的比较显示,试剂盒提取法的实验成本、步骤数和时间都是最高;其他3种方法步骤数一致,其中FTA卡所需仪器设备最少,常规煮沸法单次成本最低,裂解液提取法所需时间最少;FTA卡和裂解液提取法仅需少量菌即可提取成功,后者在时间方面优于FTA卡,但相较于FTA卡其单次成本高,所需设备多;⑤结果说明,该研究建立的FTA-LAMP技术具有操作简便、特异性强、灵敏度高、结果可视化等优势,有望为高效提取检测变异链球菌提供新途径。

关键词：变异链球菌环介导等温扩增 FTA卡 dna 可视化

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dna

商场现代化 1984年第10期 6-6页

作者：李树青

dna——脱氧核糖核酸,是英文名称deoxy—ribonucleic acid的缩写。它是生物体中的遗传物质,即dna分子就是基因。dna主要存在于细胞核中和染色体中,合成dna的主要场所是细胞核,次之是线粒体。无论那种生物体的dna都是由普通的四种碱基(... 详细信息

dna——脱氧核糖核酸,是英文名称deoxy—ribonucleic acid的缩写。它是生物体中的遗传物质,即dna分子就是基因。dna主要存在于细胞核中和染色体中,合成dna的主要场所是细胞核,次之是线粒体。无论那种生物体的dna都是由普通的四种碱基(有机碱)——腺嘌呤A、胸腺嘧啶T、鸟嘌吟G和胞嘧啶C、脱氧核糖和磷酸组成的。

关键词： dna 生物体遗传信息遗传工程

dna-encoded morphological evolution of bimetallic Pd@Au core-shell nanoparticles from a high-indexed core

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Nano Research 2018年第9期11卷 4549-4561页

作者： Nitya Sai Reddy Satyavolu Nikou Pishevaresfahani Li Huey Tan Department of Chemistry Beckman Institute for Advanced Science and Technology University of Illinois at Urbana-Champoign UrbanaIllinois 61801 USA

dna-mediated synthesis of nanopartides is a powerful method to access exclusive shapes and surface properties. Previous studies employed seeds containing low-energy facets, such as a simple cubic palladium seed, in the synthesis of Pd-Au bimetallic nanoparticles; however, few studies have investigated whether dna molecules are influential when a seed containing high-energy facets is used. Seeds enclosed by high-energy facets act as facile nucleation sites in nanopartide growth and could suppress the effect of dna. We report the dna-encoded control of the morphological evolution of bimetallic Pd@Au core-shell nanoparticles from a concave palladium nanocube seed containing high-indexed facets. Based on detailed spectroscopic and microscopic studies of time-dependent growth of bimetallic nanoparticles, we found that the dna molecules containing 10 repeating units of thymine, guanine, cytosine, or adenine （referred to as T10, G10, C10, and A10, respectively） show a unique interaction with the surface of the seed and the precursor. The most important factor is the binding affinity of the nucleobase to the Pd surface; A10 shows the highest binding affinity and can stabilize the high energy surfaces of the seed. Initially, the growth of bases with lower binding affiru＇ties （T10, G10, and C10） is completely dictated by the seed＇s surface energy, but later growth can be influenced by different dna sequences, providing four Pd@Au bimetallic nanopartides with unique morphologies. The effect of these dna molecules with medium or low binding affinities can only be observed when more Au is deposited. We propose a scheme for dna-controlled growth. These results provide insights into the factors governing the dna-mediated growth of core-shell structures using seeds with high-energy sites, and the insights can be readily applied to other bimetallic systems.

关键词： concave seed dna shape-control Pd@Au core-shell nanoparticles

Efficient renal clearance of dna tetrahedron nanopartides enables quantitative evaluation of kidney function

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Nano Research 2019年第3期12卷 637-642页

作者： Dawei Jiang Hyung-Jun lm Madeline E. Boleyn Christopher G. England Dalong Ni Lei Kang Jonathan W. Engle Peng Huang Xiaoli Lan Weibo Cai Departments of Radiology and Medical Physics University of Wisconsin-Madison Madison Wisconsin 53705 USA Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging Carson International Cancer Center Laboratory of Evolutionary Theranostics School of Biomedical Engineering Health Science Center Shenzhen University Shenzhen 518060 China Graduate School of Convergence Science and Technology Seoul National University Seoul 08826 Republic of Korea Departments of Mathematics and Biology University of Wisconsin-Madison Wisconsin 53705 USA Department of Nuclear Medicine Peking University First Hospital Beijing 100034 China Department of Nuclear Medicine Union Hospital Tortgji Medical College Huazhong University of Science and TechnologyHubei Key Laboratory of Molecular Imaging No. 1277 fiefangAve Wuhan 430022 China

dna tetrahedro n nano structure (DTN) is one of the simplest dna nano structures and has bee n successfully applied for biose nsin g, imagi ng, and treatment of can cer. To facilitate its biomedical applications and pote ntial clinical tran slation, fun dame ntal un derstandi ng of DTN's transportation among major organs in living organisms becomes increasingly important. Here, we describe the efficient renal clearanee of DTN in healthy mice by using positron emission tomography (PET) imaging. The kidney elimination of DTN was later applied for renal function evaluation in murine models of unilateral ureteral obstruction (UUO). We further established a mathematical program of DTN to validate its changes of transportation pattern in healthy and UUO mice. We believe the establishment of pharmacokinetic profiles and mathematical model of DTN may provide in sight for future optimization of dna nano structures for biomedical applications.

关键词： positron emission tomography (PET) imaging dna nanotechnology dna tetrahedron nanoparticle renal clearanee kidney dysfunction

dna damage in nucleosomes

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Science China Chemistry 2019年第5期62卷 561-570页

作者： Mengtian Ren Jing Bai Zhen Xi Chuanzheng Zhou State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology College of ChemistryNankai University

Eukaryotic genomic dna is packed into chromatin, whose fundamental structural unit is the nucleosome. As dna-histone protein complexes, nucleosomes show different properties toward exogenous and endogenous dna-damaging agents. This review summarizes nucleosome dna damage due to different sources, including alkylating agents, radicals, UV radiation and reactive dna damage intermediates. In most cases, the histone core protects the associated dna against damage via its structure and/or scavenging of damaging agents. In contrast, histones react with damaged dna and, in some instances, catalyze dna damage in the nucleosome. The biological consequence of nucleosome dna damage and future prospects in this field are briefly discussed.

关键词： dna damage dna alkylation dna-protein cross-link nucleosome radical reactive intermediate

Recent progress report on dna B-Z transition modulated by rare earth-amino acid complex and Alzheimer's disease amyloid beta

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Journal of Rare Earths 2010年第6期28卷 820-823页

作者：耿杰曲晓刚 State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Graduate School of the Chinese Academy of Sciences

Rare earth elements have unique physical, magnetic, luminescent and catalytic properties. They have been successfully used as medicine and probes in luminescent resonance energy transfer (LRET) for bioassays, as well as reagents for diagnosis in magnetic resonance imaging (MRI). In this progress report, we will focus on recent progress on how rare earth amino complexes bind to dna and change dna structure, especially on dna B-Z transition induced by rare earth amino acid complex and its potential impact on Alzheimer’s disease (AD).

关键词： dna Z-dna conformation amyloid beta Alzheimer's disease rare earths

Protein crystallization with dna templates

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Particuology 2024年第3期86卷 262-268页

作者： Bo Zhang Jia Yu Zhe Pu Wenhui Guo Ruoqi Yang Yu Wen Zhijiang Rong Hui Wang Xiaoli Wu Bo Wang Hongyan Sun School of Environment and Resources Taiyuan University of Science and TechnologyTaiyuan030024China School of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein *** is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization *** is biologically compatible and artificially designable polymer,which is easy to *** this study,single-and double-stranded dna of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and ***-fluence of dna,single-stranded dna with 10,20,40 bases and double-stranded dna with 10,20,40 base pairs,were *** success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of dna comparing without templates ***-stranded dna led to higher nucleation rate than that with single-stranded *** promotion of nucleation was more obvious at low concentration of protein solution and with longer chain dna *** number and crystallization rate was enhanced with addition of long double-stranded dna *** the results confirm that dna is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： dna Polymer Additive Protein Crystallization

Dual-enzyme-propelled unbounded dna walking nanomachine for intracellular imaging of lowly expressed microRNA

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Nano Research 2019年第5期12卷 1055-1060页

作者： Tianshu Chen Yaoyao Chen Huinan Chen Fan Zhang Qianqian Zhang Guifang Chen Xiaoli Zhu Center for Molecular Recognition and Biosensing School of Life SciencesShanghai UniversityShanghai 200444China Institute of Biomedical Engineering School of Communication and Information EngineeringShanghai UniversityShanghai 200444China Department of Bioengineering University of WashingtonSeattleWA 98195USA

Despite the progress on the analysis of miRNA either in vitro or in vivo,intracellular imaging of lowly expressed microRNA remains a *** we develop a novel dual-enzyme-propelled dna walking nanomachine,which is tailored to accomplish this *** nanomachine is constructed with nanoparticles-loaded dna tracks,on which the targeted miRNA working as a single-foot dna walker can move autonomously under the catalysis of two cooperative *** of the dna tracks like a "burnt-bridge" mechanism is thereafter triggered,resulting in an amplified fluorescent *** the comprehensive study and optimization of the dna nanomachine,miR-892b,a significantly down-regulated miRNA in breast cancer cells,is selected as a model *** detection in vitro is achieved with a superior detection limit of 4 *** being delivered into cells,the dna nanomachine is available for the imaging of the lowly expressed microRNA,which is totally missing using the conventional fluorescence in situ hybridization (FISH) ***-regulation or down-regulation of the miRNA by exogenous regulatory factors can be also well *** dna nanomachine provides a competitive approach for the analysis of miRNA,and has the potential to be extended to some other biomolecules.

关键词： dna walker nanomachine microRNA nanoparticles imaging analysis