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新型超声快速处理活检标本保存不同年限对DNA质量的影响
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作者 石晨曦 朱卫东 +3 位作者 李三恩 李秀明 师逢 丁亚云 《中国组织工程研究》 CAS 北大核心 2025年第13期2655-2660,共6页
背景:新型超声组织处理技术越来越多地被用来进行分子生物学分析,研究新型超声处理不同存储年限组织DNA的质量,对进一步分子检测的标本质控具有重要意义。目的:探讨新型超声处理活检标本存储不同年限对DNA质量的影响,以期为分子检测探... 背景:新型超声组织处理技术越来越多地被用来进行分子生物学分析,研究新型超声处理不同存储年限组织DNA的质量,对进一步分子检测的标本质控具有重要意义。目的:探讨新型超声处理活检标本存储不同年限对DNA质量的影响,以期为分子检测探索最佳的标本存储时间。方法:收集40例乳腺穿刺小活检组织,采用超声技术制作石蜡标本,按照存储年限分为4组:<1年组、1-3年组、>3-5年组及>5年组,每组10例,对石蜡标本进行切片,每张切片厚3μm,切片10-15张,提取DNA后通过Nanophotometer N60超微量分光光度计和Qubit 4.0荧光计检测DNA的质量浓度,记录A_(260)/A_(280)比值判定DNA的纯度,利用全自动毛细管电泳核酸分析仪(Qsep 100)检测DNA片段完整性,以评估DNA片段的质量。结果与结论:4组样本A_(260)/A_(280)均值在1.8-2.0之间,达到纯度要求,无明显差异。4组样本的DNA质量浓度(Qubit浓度)均值分别为30.39,14.33,2.52,1.95 ng/μL;DNA的平均N/Q比值分别为6.48,14.18,24.56,29.86;DNA质量数均值分别为5.64,1.76,1.24,0.80;大片段占比均值分别为56.08%,17.72%,12.68%,7.90%。PCR检测内控基因Ct均值分别为15.32,17.09,18.39,21.24。与<1年组相比,其余3组DNA浓度显著降低,N/Q比值显著增加,DNA质量数和大片段占比均值显著降低,Ct值升高,差异有显著性意义(P<0.05)。实验结果表明,对于新型超声处理活检标本,应优先选择存储<1年的样本进行日常分子检测,储存3年内的样本可满足二代测序等检测要求,5年内样本仅可尝试进行PCR等检测,存储超过5年的样本不建议进行后续分子检测。 展开更多
关键词 超声处理 存储年限 dna质量 片段完整性 降解程度 二代测序
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Potential control of DNA self-assembly on gold electrode 被引量:2
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作者 Cunwang Ge Yibin Tan +3 位作者 Jianhui Liao Yu Zhang Haiqian Zhang Ning Gu 《Chinese Science Bulletin》 SCIE EI CAS 2002年第5期370-375,共6页
The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. A new approach based on potential was first used to control DNA self-assembly covalently onto the SAM with the activa... The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. A new approach based on potential was first used to control DNA self-assembly covalently onto the SAM with the activation of l-ethyl-3(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysulfosuccinimide (NHS). The influence of potential on DNA self-assembly was investigated by means of cyclic voltammetry (CV), AC impedance, Auger electron spectrometry (AES) and atomic force microscopy (AFM). The result proves that controlled potential can affect the course of DNA self-assembly. More negative potential can restrain the DNA self-assembly, while more positive potential can accelerate the DNA self-assembly, which is of great significance for the control of DNA self-assembly and will find wide application in the field of DNA-based devices. 展开更多
关键词 dna self-assembly CONTROLLED POTENTIAL dna-based device GOLD electrode.
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基于中医证候与精液质量相关参数构建精子DNA碎片预测模型与验证
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作者 周超 庾广聿 +4 位作者 阳绍华 高磊磊 金珍 蒋月园 李欢 《中国组织工程研究》 CAS 北大核心 2025年第13期2661-2668,共8页
背景:中医证候与精液质量相关参数相结合,共同预测精子DNA碎片指数(DNA fragmentation index,DFI)异常增高的发生并绘制列线图,能显著提高临床的实操性与应用效能,为临床全面评估精液质量,采取积极干预措施以改善临床结局及制定个体化... 背景:中医证候与精液质量相关参数相结合,共同预测精子DNA碎片指数(DNA fragmentation index,DFI)异常增高的发生并绘制列线图,能显著提高临床的实操性与应用效能,为临床全面评估精液质量,采取积极干预措施以改善临床结局及制定个体化医疗方案提供依据。目的:探讨基于中医证候与精液质量相关参数构建精子DNA碎片的预测模型与验证。方法:回顾性分析2019年7月至2021年7月在广西壮族自治区南溪山医院中医男科接受中医证候诊断及精子DNA碎片率检查的不育患者共420例,据《人类精液检查与处理实验室手册》(第6版),将其中137例精子DFI>30%患者纳入精子DFI异常增高组,将283例精子DFI≤30%作为对照组;首先采用单因素分析筛选精子DFI异常增高的影响因素,然后采用套索算法(LASSO)校正因子共线性问题并筛选出最佳匹配因子后,将其纳入多因素向前逐步Logistic回归找出其独立影响因素并绘制列线图,最后采用受试者工作曲线、校准曲线、临床决策曲线、临床影响曲线对该预测模型进行区分度与准确度及临床应用效能验证。结果与结论:①单因素分析结果显示,年龄、体质量指数、前向运动率、精子总活率、精子浓度、精子形态学、肾阳虚衰证、湿热下注证、肾精不足证为引发精子DFI异常增高的影响因子(P<0.05);②通过LASSO回归进一步筛选出的最佳匹配因素为年龄、体质量指数、精子总活率、精子浓度、精子形态学、肾阳虚衰证、湿热下注证、肾精不足证(P<0.05);③多因素向前逐步Logistic回归结果显示年龄、体质量指数、精子浓度、精子总活率、湿热下注证、肾阳虚衰证共6项为引发精子DFI异常增高的独立影响因素;④受试者工作曲线显示,模型组曲线下面积为0.760(0.713,0.806),验证组曲线下面积为0.745(0.714,0.776),说明该预测模型具有较好的区分度;⑤校准曲线平均绝对误差0.040,Hosmer-Lemeshow检验P>0.05,表明该模型预测发生精子DFI异常增高的概率与实际发生精子DFI异常增高的概率无显著统计学差异,证实该模型具有较好的准确度;⑥临床决策曲线与临床影响曲线显示,模型组与验证组分别在阈概率值为0.08-0.84与0.09-0.78时具有临床最大净获益,且在该阈概率范围内具有较好的临床应用效能;⑦结果表明,年龄、体质量指数、精子浓度、精子总活率、湿热下注证、肾阳虚衰证为引发精子DFI异常增高的独立影响因素,通过其构建的临床预测模型列线图具有较好的临床预测价值与临床应用效能,可为临床全面评估精液质量、预后与干预及个体化医疗服务提供依据。 展开更多
关键词 精子dna碎片 精子dna完整性 中医证候 精子dna碎片指数 预测模型
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A molecular cryptography model based on structures of DNA self-assembly 被引量:5
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作者 Jing Yang Jingjing Ma +1 位作者 Shi Liu Cheng Zhang 《Chinese Science Bulletin》 SCIE EI CAS 2014年第11期1192-1198,共7页
With the progress of DNA computing, DNAbased cryptography becomes an emerging interdisciplinary research field. In this paper, we present a novel DNA cryptography that takes advantage of DNA self-assembled structure. ... With the progress of DNA computing, DNAbased cryptography becomes an emerging interdisciplinary research field. In this paper, we present a novel DNA cryptography that takes advantage of DNA self-assembled structure. Making use of the toehold strands recognition and strand displacement, the bit-wise exclusive-or(XOR)operation is carried out to fulfill the information encryption and decryption in the form of a one-time-pad. The security of this system mainly comes from the physical isolation and specificity of DNA molecules. The system is constructed by using complex DNA self-assembly, in which technique of fluorescent detection is utilized to implement the signal processing. In the proposed DNA cryptography,the XOR operation at each bit is carried out individually,thus the encryption and decryption process could be conducted in a massive, parallel way. This work may demonstrate that DNA cryptography has the great potential applications in the field of information security. 展开更多
关键词 dna计算 自组装结构 信息加密 分子模型 dna密码 异或运算 dna分子 物理隔离
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Molecular logic computing model based on DNA self-assembly strand branch migration 被引量:2
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作者 ZHANG Cheng MA LiNa +2 位作者 DONG YaFei YANG Jing XU Jin 《Chinese Science Bulletin》 SCIE EI CAS 2013年第1期32-38,共7页
In this study,the DNA logic computing model is established based on the methods of DNA self-assembly and strand branch migration.By adding the signal strands,the preprogrammed signals are released with the disintegrat... In this study,the DNA logic computing model is established based on the methods of DNA self-assembly and strand branch migration.By adding the signal strands,the preprogrammed signals are released with the disintegrating of initial assembly structures.Then,the computing results are able to be detected by gel electrophoresis.The whole process is controlled automatically and parallely,even triggered by the mixture of input signals.In addition,the conception of single polar and bipolar is introduced into system designing,which leads to synchronization and modularization.Recognizing the specific signal DNA strands,the computing model gives all correct results by gel experiment. 展开更多
关键词 dna 运算模型 自组装 逻辑 迁移 输入信号 分子 凝胶电泳
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Self-assembly of perovskite nanocrystals:From driving forces to applications
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作者 Yi Li Fei Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期561-578,I0013,共19页
Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review ... Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are detailed.Subsequently,we summarize the collective optoelectronic properties and application areas of perovskite superlattice structures.Finally,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs. 展开更多
关键词 self-assembly Metal halide perovskite NANOCRYSTALS Driving forces
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Alcohol solvent effect on the self-assembly behaviors of lignin oligomers
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作者 Ya Ma Zhicheng Jiang +4 位作者 Yafei Luo Xingjie Guo Xudong Liu Yiping Luo Bi Shi 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期597-603,共7页
The interactions between lignin oligomers and solvents determine the behaviors of lignin oligomers self-assembling into uniform lignin nanoparticles(LNPs).Herein,several alcohol solvents,which readily interact with th... The interactions between lignin oligomers and solvents determine the behaviors of lignin oligomers self-assembling into uniform lignin nanoparticles(LNPs).Herein,several alcohol solvents,which readily interact with the lignin oligomers,were adopted to study their effects during solvent shifting process for LNPs’production.The lignin oligomers with widely distributed molecular weight and abundant guaiacyl units were extracted from wood waste(mainly consists of pine wood),exerting outstanding self-assembly capability.Uniform and spherical LNPs were generated in H_(2)O-n-propanol cosolvent,whereas irregular LNPs were obtained in H_(2)O-methanol cosolvent.The unsatisfactory self-assembly performance of the lignin oligomers in H_(2)O-methanol cosolvent could be attributed to two aspects.On one hand,for the initial dissolution state,the distinguishing Hansen solubility parameter and polarity between methanol solvent and lignin oligomers resulted in the poor dispersion of the lignin oligomers.On the other hand,strong hydrogen bonds between methanol solvent and lignin oligomers during solvent shifting process,hindered the interactions among the lignin oligomers for self-assembly. 展开更多
关键词 Lignin oligomers Alcohol solvent self-assembly LNPs Solvent effects
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Chitosan/Sodium Alginate Multilayer pH-Sensitive Films Based on Layer-by-Layer Self-Assembly for Intelligent Packaging
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作者 Mingxuan He Yahui Zheng +4 位作者 Jiaming Shen Jiawei Shi Yongzheng Zhang Yinghong Xiao Jianfei Che 《Journal of Renewable Materials》 EI CAS 2024年第2期215-233,共19页
The abuse of plastic food packaging has brought about severe white pollution issues around the world.Developing green and sustainable biomass packaging is an effective way to solve this problem.Hence,a chitosan/sodium... The abuse of plastic food packaging has brought about severe white pollution issues around the world.Developing green and sustainable biomass packaging is an effective way to solve this problem.Hence,a chitosan/sodium alginate-based multilayer film is fabricated via a layer-by-layer(LBL)self-assembly method.With the help of superior interaction between the layers,the multilayer film possesses excellent mechanical properties(with a tensile strength of 50 MPa).Besides,the film displays outstanding water retention property(blocking moisture of 97.56%)and ultraviolet blocking property.Anthocyanin is introduced into the film to detect the food quality since it is one natural plant polyphenol that is sensitive to the pH changes ranging from 1 to 13 in food when spoilage occurs.It is noted that the film is also bacteriostatic which is desired for food packaging.This study describes a simple technique for the development of advanced multifunctional and fully biodegradable food packaging film and it is a sustainable alternative to plastic packaging. 展开更多
关键词 CHITOSAN ALGINATE layer-by-layer self-assembly PH-SENSITIVE multilayer films
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Hollow tubes constructed by carbon nanotubes self-assembly for CO_(2) capture
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作者 CHEN Xu-rui WU Jun +1 位作者 GU Li CAO Xue-bo 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2256-2267,共12页
Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their mac... Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their macroscopic assembly.The present study employed a gentle and direct self-assembly technique,wherein controlled growth of CNT sheaths occurred on the metal wire’s surface,followed by etching of the remaining metal to obtain the hollow tubes composed of CNTs.By controlling the growth time and temperature,it is possible to alter the thickness of the CNTs sheath.After immersing in a solution containing 1 g/L of CNTs at 60℃ for 24 h,the resulting CNTs layer achieved a thickness of up to 60μm.These hollow CNTs tubes with varying inner diameters were prepared through surface reinforcement using polymers and sacrificing metal wires,thereby exhibiting exceptional attributes such as robustness,flexibility,air tightness,and high adsorption capacity that effectively capture CO_(2) from the gas mixture. 展开更多
关键词 carbon nanotubes self-assembly hollow tubes CO_(2) capture
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基于活产建立体外受精-胚胎移植精子DNA碎片指数的参考阈值及子代短期安全性
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作者 周超 王淑娴 +2 位作者 于春梅 庾广聿 蒋月园 《中国组织工程研究》 CAS 北大核心 2025年第1期111-119,共9页
背景:精子DNA碎片指数与受精、胚胎发育潜能、胚胎植入、流产及子代安全性等存在显著的相关性。然而,其临床参考值受多种因素的影响,导致临床意义极其有限,该研究以活产为结局,通过倾向评分匹配校正其他混杂因素后,构建精子DNA碎片指数... 背景:精子DNA碎片指数与受精、胚胎发育潜能、胚胎植入、流产及子代安全性等存在显著的相关性。然而,其临床参考值受多种因素的影响,导致临床意义极其有限,该研究以活产为结局,通过倾向评分匹配校正其他混杂因素后,构建精子DNA碎片指数与活产的最佳临床截断值,并对其进行内外部验证,具有较好的预测价值及临床应用效能。目的:探讨基于活产建立体外受精-胚胎移植精子DNA碎片指数的参考阈值及子代短期安全性。方法:选取2019年5月至2021年5月于常州市妇幼保健院接受体外受精-胚胎移植患者1921例,以倾向匹配容差0.02为标准,1∶1进行倾向评分匹配,结果活产组与非活产组各成功匹配540例,以此建立模型组;通过选取同时期广西壮族自治区南溪山医院接受体外受精-胚胎移植患者135例作为外部验证组;采用受试者工作曲线探求精子DNA碎片指数对活产的临床最佳截断值,分别采用限制性立方样条曲线、标准曲线、临床决策曲线、临床影响曲线及内外部验证等方法,对该截断值的准确性及临床应用效能进行评估。结果与结论:(1)非活产组精子DNA碎片指数显著高于活产组且与活产存在显著的负相关性(r=-0.444,P<0.001);(2)受试者工作曲线结果显示,DNA碎片指数对活产的最佳截断值为24.33%,曲线下面积为0.775(0.746,0.804),特异度为72.60%,敏感度为78.90%,准确度为75.70%;(3)限制性立方样条曲线拟合Logistic回归结果显示,当精子DNA碎片指数大于24.57%时,临床非活产的风险呈趋势性增涨;(4)Logistic回归概率分析结果显示,精子DNA碎片指数为活产的危险因素[OR(95%CI)=0.916(0.904,0.928),P<0.001],且当精子DNA碎片指数大于27.78%时,临床活产发生的概率将小于50%,随着精子DNA碎片指数每增高1个单位,活产的概率下降8.4%;(5)内外部对该临床截断值的验证均显示,该截点具有一定的临床预测价值及准确性;(6)临床决策曲线与临床影响曲线显示,以该临床截断值建立的预测模型在阈概率为0.22-0.73时具有临床最大净获益值,且在该阈概率范围内损失与获益的比值始终小于1,证实该预测模型具有较好的临床应用效能;(7)精子DNA碎片指数与子代短期安全性分析结果显示,精子DNA碎片指数与出生儿早产、体质量、畸形、性别差异无显著性;(8)结果表明,精子DNA碎片指数对体外受精-胚胎移植活产的最佳临床截断值为24.33%,以此建立的临床预测模型具有较好的区分度、准确度与临床应用效能,精子DNA碎片指数对子代短期安全性影响并不显著,但仍需大样本及长期的追踪评估。 展开更多
关键词 精子dna碎片指数 活产 体外受精-胚胎移植 子代安全性 最佳截断值
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A Non-parametric Gradient-Based Shape Optimization Approach for Solving Inverse Problems in Directed Self-Assemblyof Block Copolymers
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作者 Daniil Bochkov Frederic Gibou 《Communications on Applied Mathematics and Computation》 EI 2024年第2期1472-1489,共18页
We consider the inverse problem of finding guiding pattern shapes that result in desired self-assembly morphologies of block copolymer melts.Specifically,we model polymer selfassembly using the self-consistent field t... We consider the inverse problem of finding guiding pattern shapes that result in desired self-assembly morphologies of block copolymer melts.Specifically,we model polymer selfassembly using the self-consistent field theory and derive,in a non-parametric setting,the sensitivity of the dissimilarity between the desired and the actual morphologies to arbitrary perturbations in the guiding pattern shape.The sensitivity is then used for the optimization of the confining pattern shapes such that the dissimilarity between the desired and the actual morphologies is minimized.The efficiency and robustness of the proposed gradient-based algorithm are demonstrated in a number of examples related to templating vertical interconnect accesses(VIA). 展开更多
关键词 Block copolymers Directed self-assembly Inverse design Shape optimization Vertical interconnect accesses(VIA)
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Confined cobalt single-atom catalysts with strong electronic metal-support interactions based on a biomimetic self-assembly strategy
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作者 Bowen Guo Zekun Wang +3 位作者 Lei Zheng Guang Mo Hongjun Zhou Dan Luo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期156-171,共16页
Designing high-performance and low-cost electrocatalysts for oxygen evolu-tion reaction(OER)is critical for the conversion and storage of sustainable energy technologies.Inspired by the biomineralization process,we ut... Designing high-performance and low-cost electrocatalysts for oxygen evolu-tion reaction(OER)is critical for the conversion and storage of sustainable energy technologies.Inspired by the biomineralization process,we utilized the phosphorylation sites of collagen molecules to combine with cobalt-based mononuclear precursors at the molecular level and built a three-dimensional(3D)porous hierarchical material through a bottom-up biomimetic self-assembly strategy to obtain single-atom catalysts confined on carbonized biomimetic self-assembled carriers(Co SACs/cBSC)after subsequent high-temperature annealing.In this strategy,the biomolecule improved the anchoring efficiency of the metal precursor through precise functional groups;meanwhile,the binding-then-assembling strategy also effectively suppressed the nonspecific adsorption of metal ions,ultimately preventing atomic agglomeration and achieving strong electronic metal-support interactions(EMSIs).Experimental characterizations confirm that binding forms between cobalt metal and carbonized self-assembled substrate(Co–O_(4)–P).Theoretical calculations disclose that the local environment changes significantly tailored the Co d-band center,and optimized the binding energy of oxygenated intermediates and the energy barrier of oxygen release.As a result,the obtained Co SACs/cBSC catalyst can achieve remarkable OER activity and 24 h durability in 1 M KOH(η10 at 288 mV;Tafel slope of 44 mV dec-1),better than other transition metal-based catalysts and commercial IrO_(2).Overall,we presented a self-assembly strategy to prepare transition metal SACs with strong EMSIs,providing a new avenue for the preparation of efficient catalysts with fine atomic structures. 展开更多
关键词 biomimetic self-assembly support electronic metal-support interactions oxygen evolution reaction single atoms catalysts
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Layer by Layer Self-assembly Fiber-based Flexible Electrochemical Transistor
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作者 谭艳 HAO Panpan +2 位作者 HE Yang ZHU Rufeng 王跃丹 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期937-944,共8页
Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface mo... Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface morphology and electric property was investigated.The results confirmed the dense membrane of PEDOT:PSS and the lamellar structure of PDDA-rGO on the fibers.It has excellent electrical conductivity and mechanical properties.The fiber based electrochemical transistor(FECTs)prepared by the composite conductive fiber has a maximum output current of 8.7 mA,a transconductance peak of 10 mS,an on time of 1.37 s,an off time of 1.6 s and excellent switching stability.Most importantly,the devices by layer by layer self-assembly technology opens a path for the true integration of organic electronics with traditional textile technologies and materials,laying the foundation for their later widespread application. 展开更多
关键词 layer by layer self-assembly fiber based organic electrochemical transistor reduced graphene oxide PEDOT:PSS
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FABRICATION OF SELF-ASSEMBLY DNA-C_(60) MULTILAYER FILMS
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作者 Shu-guang Yang Yong-jun Zhang +5 位作者 Xin-hua Dai Wen-hong Tang Chun-yan Liu Wei-xiao Cao Yu-liang Li Jian Xu State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences,Beijing 100080, China Technology Institute of Physics and Chemistry Chinese Academy of Sciences, Beijing 100101, China College of Chemistry and Molecular Engineering Peking University Beijing 100871, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第6期591-593,共3页
Electrostatic layer-by-layer self-assembly multilayer films were successfully fabricated from C-60-ethylenediamine adduct (C-60-EDA) and DNA. Under visible light irradiation, DNA is ready to be cleaved and the films a... Electrostatic layer-by-layer self-assembly multilayer films were successfully fabricated from C-60-ethylenediamine adduct (C-60-EDA) and DNA. Under visible light irradiation, DNA is ready to be cleaved and the films are destroyed. 展开更多
关键词 self-assembly photo-induced cleavage dna C-60
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pH-Responsive Reversible DNA Self-assembly Mediated by Zwitterion 被引量:1
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作者 DONG Yuhang PAN Xiaorui +1 位作者 LI Feng YANG Dayong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2020年第2期285-290,共6页
pH-Responsive DNA assembles have drawn growing attentions owing to their great potential in diverse areas.However,pH-responsive motifs are limited to specific DNA sequences and annealing is usually needed for DNA asse... pH-Responsive DNA assembles have drawn growing attentions owing to their great potential in diverse areas.However,pH-responsive motifs are limited to specific DNA sequences and annealing is usually needed for DNA assemblies;therefore,sequence-independent pH-responsive DNA assembly at room temperature is highly desired as a more general way.Here,we propose a reversible pH-responsive DNA assembly strategy at room-temperature using zwitterion,glycine betaine(GB),as charge-regulation molecules.The reversible assembly and disassembly of DNA nanostructures could be achieved by alternatively regulating the acidic and basic environments in the presence of GB,respectively.In an acidic environment,carboxylate group in GB was protonated and GB was positively charged,which facilitated to shield the inherent electrostatic repulsion of DNA strands.Molecular simulation showed that the newly formed carboxyl group in protonated GB could form hydrogen bonds with bases in DNA to promote the assembly of DNA strands.In a basic solution,carboxylate group in GB was deprotonated and GB was neutral,thus inducing the dissociation of DNA assembly. 展开更多
关键词 dna NANOTECHNOLOGY Dynamic assembly pH RESPONSIVENESS ZWITTERION
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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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作者 王玥晖 尚进 +4 位作者 杨晨 符冬格 曹灿 张晓东 王敬夫 《中国组织工程研究》 CAS 北大核心 2025年第5期1043-1049,共7页
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... 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。 展开更多
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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Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder
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作者 Jinmei Ye Cong Duan +5 位作者 Jiaxin Han Jinrong Chen Ning Sun Yuan Li Tifei Yuan Daihui Peng 《Neural Regeneration Research》 SCIE CAS 2025年第6期1541-1554,共14页
In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release f... In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder. 展开更多
关键词 BIOMARKER cytokine EXOSOMES INFLAMMASOME major depressive disorder MICROGLIA mitochondrial dna mitochondrial dysfunction NEUROINFLAMMATION Toll-like receptor
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基于环境DNA技术的珠江中下游鱼类多样性初步研究 被引量:1
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作者 朱书礼 陈蔚涛 +4 位作者 武智 夏雨果 杨计平 李跃飞 李捷 《南方水产科学》 CAS CSCD 北大核心 2024年第1期120-129,共10页
通过环境DNA技术(Environmental DNA,eDNA)检测珠江中下游鱼类生物多样性,探索珠江中下鱼类多样性监测和保护的新途径。2023年2月在珠江中下游设置了桂平、藤县、封开、德庆、肇庆和九江共6个采样点,通过水样采集及过滤、eDNA提取、遗... 通过环境DNA技术(Environmental DNA,eDNA)检测珠江中下游鱼类生物多样性,探索珠江中下鱼类多样性监测和保护的新途径。2023年2月在珠江中下游设置了桂平、藤县、封开、德庆、肇庆和九江共6个采样点,通过水样采集及过滤、eDNA提取、遗传标记扩增及测序和数据库比对分析等流程检测鱼类多样性。结果表明,6个采样点共检测出30种鱼类,隶属于4目10科27属,其中土著鱼类26种,外来种4种。较已有传统调查数据新检出2种鱼类:美丽沙鳅(Botia pulchra)和齐氏罗非鱼(Oceochromis zillii)。鱼类优势种为子陵吻鰕虎鱼(Rhinogobius giurinus)、瓦氏黄颡鱼(Pelteobagrus vachellii)、鲢(Hypophthalmichthys molitrix)、尼罗罗非鱼(O.nilotica)、齐氏罗非鱼、南方波鱼(Rasbora steineri)和鲤(Cyprinus carpio)。根据Shannon指数和Simpson指数显示,eDNA检测九江和桂平站点的鱼类多样性最高,藤县的最低。作为一种新的检测方法,eDNA技术可用于快速检测珠江中下游鱼类的多样性及分布,在实际应用中可将eDNA技术与传统的监测方法相结合,以提供更全面的鱼类生物多样性数据信息。 展开更多
关键词 环境dna(edna) 鱼类多样性 珠江中下游
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温和灸足三里穴对自然衰老大鼠肾组织p16 DNA甲基化的影响 被引量:1
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作者 刘文博 赵舒羽 +6 位作者 殷之光 杨秋红 崔云华 黄艳 焦丹丽 吴焕淦 赵琛 《上海针灸杂志》 CSCD 2024年第2期210-218,共9页
目的 观察温和灸足三里穴对自然衰老大鼠肾组织p16 DNA甲基化的调控作用及潜在机制。方法 将Sprague-Dawley(SD)大鼠随机分为12月龄组、24月龄组和艾灸组。24月龄组和艾灸组制备自然衰老模型。12月龄组和24月龄组大鼠不予治疗,待相应时... 目的 观察温和灸足三里穴对自然衰老大鼠肾组织p16 DNA甲基化的调控作用及潜在机制。方法 将Sprague-Dawley(SD)大鼠随机分为12月龄组、24月龄组和艾灸组。24月龄组和艾灸组制备自然衰老模型。12月龄组和24月龄组大鼠不予治疗,待相应时间取材;艾灸组采用温和灸足三里穴至24月龄取材。采用免疫荧光法观察3组大鼠肾组织衰老相关标志物β-半乳糖苷酶的表达。采用酶联免疫吸附法和免疫组织化学法检测3组大鼠肾组织衰老相关p16蛋白及甲基转移酶[甲基转移酶3a(DNA methyltransferase 3a,Dnmt3a)和甲基转移酶3b(DNA methyltransferase 3b,Dnmt3b)]蛋白的表达。采用定量反转录聚合酶连锁反应(quantitative real time-polymerase chain reaction,qRT-PCR)法检测3组大鼠肾组织端粒长度、肾组织衰老相关p16 mRNA及甲基转移酶(Dnmt3a和Dnmt3b) mRNA表达。采用重亚硫酸盐测序技术检测3组大鼠肾组织p16 DNA CpG岛甲基化程度。结果 与12月龄组比较,24月龄组大鼠肾组织β-半乳糖苷酶表达、端粒长度的损耗及衰老相关p16蛋白和mRNA表达水平升高(P<0.05),24月龄组大鼠肾组织Dnmt3a和Dnmt3b蛋白及mRNA表达水平降低(P<0.05)。与24月龄组比较,艾灸组大鼠肾组织β-半乳糖苷酶表达、端粒长度的损耗及肾组织衰老相关p16蛋白和mRNA表达显著降低(P<0.05),艾灸组大鼠肾组织Dnmt3a和Dnmt3b蛋白及mRNA表达显著升高(P<0.05)。结论温和灸可通过影响自然衰老大鼠肾组织衰老相关甲基转移酶的表达调控p16 DNA CpG岛整体甲基化水平,降低肾组织p16蛋白及mRNA在衰老机体肾组织的表达,延缓肾组织衰老进程。 展开更多
关键词 灸法 温和灸 艾条灸 衰老 dna甲基化 大鼠
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HBsAg ELISA+/HBV DNA NAT-献血者血清学与分子生物学特征分析 被引量:1
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作者 景媛媛 范云 +3 位作者 郭燕 张文娟 段勇 冯娜 《中国输血杂志》 CAS 2024年第4期412-416,共5页
目的 了解西安地区无偿献血人群HBsAg ELISA检测结果与HBV DNA检测结果不一致的标本相关血清学标志物的分布情况。方法 收集2022年11月1日—2023年4月30日陕西省血液中心HBsAg ELISA+/HBV DNA NAT-(ELISA+/NAT-)标本共计71份,对其采用... 目的 了解西安地区无偿献血人群HBsAg ELISA检测结果与HBV DNA检测结果不一致的标本相关血清学标志物的分布情况。方法 收集2022年11月1日—2023年4月30日陕西省血液中心HBsAg ELISA+/HBV DNA NAT-(ELISA+/NAT-)标本共计71份,对其采用电化学发光法检测乙肝血清学标志物,同时复检巢式PCR扩增HBV S区和C区基因片段。结果 双ELISA+/NAT-标本(n=30)巢式PCR检测阳性率远高于单ELISA+/NAT-标本(n=41)(60%vs 24.40%,P<0.05)。前者献血者100%为初次献血者,血清抗-HBc阳性率100%,血清学模式以1、4、5此3项阳性(80%)为主;后者献血者中31.7%为重复献血者,血清抗-HBc阳性率仅为19.51%,血清学模式以单2项阳性(43.90%)和全阴(36.58%)为主。结论 单ELISA+结果存在较多假阳性,导致不必要的血液报废;而NAT-标本可能存在低水平的HBV DNA,产生漏检风险。建议针对单HBsAg ELISA+/NAT-献血者,采用多套系统多种方法追溯检测,提高献血者HBV筛查的准确度,减少不必要的血液浪费。 展开更多
关键词 乙型肝炎表面抗原 无偿献血者 巢式PCR HBV dna
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