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生物医用材料旨在通过调控材料和细胞之间的相互作用来实现组织的再生和修复。黏附过程直接决定了细胞是否能够充分发挥生物学性能,因此通过对材料表面的物理和化学改性来调控细胞黏附,对于生物材料具有至关重要的意义,也是非常活跃的研究热点。材料表面物理改性通常通过对包括表面粗糙度、形貌、模量和多孔结构等物理性质的调控,为细胞构建适合黏附的材料表面。而化学改性则借助于表面电荷及亲疏水性调控、促黏分子修饰等化学手段来提高材料表面与细胞间的相互作用力,进而促进细胞黏附。近年来,材料表面调控细胞黏附的研究取得了许多新的突破性进展。例如在传统的促黏分子表面修饰之外,人们逐步发现对促黏分子序构的精准调控也可以有效地提高材料表面的促黏性能。而刺激响应性表面则可以根据外界信号的刺激,使得材料表面在促黏和抗黏之间实现智能的转换。本文从物理改性、化学修饰、刺激响应性表面构建等角度出发,全面总结和讨论了材料表面性质对细胞黏附的调控作用,梳理了材料表面的设计思路,多种材料表面的修饰改性方法等最新进展,并展望了未来材料表面对细胞黏附的调控思路。 相似文献
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The cell membrane is a biological interface consisting of phospholipid bilayer, saccharides and proteins that maintains a stable metabolic intracellular environment as well as regulating and controlling the exchange of substances inside and outside the cell. Cell membranes provide a highly complex biological surface carrying a variety of essential surfaces ligands and receptors for cells to receive various stimuli of external signals, thereby inducing corresponding cell responses regulating the life activities of the cell. These surface receptors can be manipulated via cell surface modification to regulate cellular functions and behaviors Thus, cell surface modification has attracted considerable attention due to its significance in cell fate control, cell engineering and cell therapy. In this minireview, we describe the recent developments and advances of cell surface modification, and summarize the main modification methods with corresponding functions and applications. Finally, the prospect for the future development of the modification of the living cell membrane is discussed. 相似文献
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熔融碳酸盐燃料电池阳极材料表面改性 总被引:1,自引:0,他引:1
选择铌作为合金化元素,通过氟化物熔盐电化学表面合金化的方法对熔融碳酸盐燃料电池阳极材料镍进行表面改性,改性后的阳极材料的耐蚀性能与电催化性能均得到明显的改善。 相似文献
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聚合物材料表面纳米条纹对生物细胞生长的影响 总被引:5,自引:1,他引:4
20世纪 80年代后期 ,工程学科与生命学科的交叉融合产生了组织工程学 [1,2 ] ,细胞与生物材料之间的相互作用是组织工程学的一个主要领域 .细胞必须与材料发生适当的粘附 ,才能进行迁移、分化和增殖 ,细胞与材料粘附及随后的扩散能力的大小主要由材料表面的物理和化学性质所决定 [3,4 ] .目前 ,材料表面改性以提高细胞粘附力是组织工程学的一大难题 .聚苯乙烯 (PS)以其无毒、高透明度、低成本以及易加工等性能 ,被广泛应用于基础医学研究及临床医学实验 [5,6 ] .未改性 PS的生物相容性较差 ,只有表面改性后才能用于细胞培养 .目前文献报道… 相似文献
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Cell migration plays a crucial role in various biological processes including embryogenests,wound healing,immune response,and tissue development~([1]).Exploring and understanding the mechanisms and related factors underlying cell migration arc also very important for emerging areas of biotedmology which focus on cellular transplantation and the manufacture of artificial tissues,as well as for the development of new therapeutic strategies for controlling invasive tumor cells~([2]). 相似文献
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ZHANG Wei-Jia① WANG Tian-Min CUI Min 《结构化学》2005,24(12):1369-1374
1 INTRODUCTION 2. 1 Madelung constant of crystal Surface energy of crystal grain has crucial influ- The Madelung constant, which is used to calculate ence on the electrical and mechanical performances lattice energy and so on[1], is of central importance in of material, especially for material making up of na- the theory of ionic crystal and property of crystal nosized crystal grains because all outstanding per- structure. There is no special difficulty in calculating formances of the mat… 相似文献
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Typical bacterial glycoconjugates are known to stimulate immunological systems of higher animals and thereby play important roles in the primary defense of animals against bacterial infection. Lipopolysaccharide (LPS) of gram‐negative bacteria is a representative of such glycoconjugates. LPS was first discovered as a potent bacterial toxin and named endotoxin but was soon found to exhibit immunostimulating activity. By the use of our synthetic pure preparations, the lipophilic partial structure of LPS, designated lipid A, proved to be the active entity responsible for both endotoxic and immunostimulating activities of LPS. This paper deals with our recent chemical synthesis and functional study of lipid A and related compounds. Synthesis is described of its various structural analogues, radio‐labeled compound and Re‐type LPS that contains two additional sugar moieties linked to lipid A. 相似文献
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《Angewandte Chemie (International ed. in English)》2017,56(8):2183-2186
We herein describe the engineering of E. coli strains that display orthogonal tags for immobilization on their surface and overexpress a functional heterologous “protein content” in their cytosol at the same time. Using the outer membrane protein Lpp‐ompA, cell‐surface display of the streptavidin‐binding peptide, the SpyTag/SpyCatcher system, or a HaloTag variant allowed us to generate bacterial strains that can selectively bind to solid substrates, as demonstrated with magnetic microbeads. The simultaneous cytosolic expression of functional content was demonstrated for fluorescent proteins or stereoselective ketoreductase enzymes. The latter strains gave high selectivities for specific immobilization onto complementary surfaces and also in the whole‐cell stereospecific transformation of a prochiral CS‐symmetric nitrodiketone. 相似文献
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Padma Ambalam Kanthi Kiran Kondepudi Ingrid Nilsson Torkel Wadström Åsa Ljungh 《Applied biochemistry and biotechnology》2014,172(4):1970-1981
Twenty-four human bifidobacterial strains were analysed for cell surface hydrophobicity (CSH) using a salt aggregation test (SAT) and a Congo red binding (CRB) assay. Three strains were selected for a systematic study on the CSH and biofilm formation: Bifidobacterium breve 46, Bifidobacterium animalis ssp. lactis 8:8 and a reference strain B. animalis ssp. lactis JCM 10602. CRB of the B. breve 46 and B. animalis ssp. lactis JCM 10602 was significantly enhanced (P?<?0.05) when grown in deMan–Rogosa–Sharpe cysteine (MRSC) broth supplemented with taurocholic acid (TA) or native porcine bile (PB). An enhanced CSH of the strains grown with PB and gastric mucin correlated with an increased mucin binding and an enhanced biofilm formation in prebiotic oligosaccharide-supplemented cultures. The three strains showed late bile-induced biofilm (72 h) under an anaerobic growth condition, and both B. animalis ssp. lactis strains showed a late bile-induced biofilm formation under aerobic conditions shown by crystal violet staining. These two strains were thus considered to be oxygen tolerant and more robust. Furthermore, enhanced biofilm formation of these robust bifidobacterial strains in the presence of prebiotics may allow for strong colonisation in the gastrointestinal tract when administered to in vivo models as a “synbiotic supplement”. 相似文献
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高密度噬菌体抗体芯片对细胞表面蛋白的识别 总被引:1,自引:0,他引:1
采用正常人和白血病患者的白细胞对人源噬菌体抗体库进行淘选, 以获得对两种细胞表面蛋白特异的抗体. 通过pVIII展示系统, 使抗体以多价展示于重组噬菌体颗粒表面, 从上述两组中各挑选出48个克隆分别固定于环氧基片上, 并以空白噬菌体和牛血清白蛋白作为对照, 制成高密度噬菌体抗体芯片. 取来自3名正常人和3名白血病患者的白细胞裂解物样品, 用荧光染料Cy3标记, 与噬菌体抗体芯片反应, 对微阵共聚焦扫描得到的荧光图谱进行分析. 在白血病白细胞表面蛋白的识别图谱中有8组斑点显著不同于正常图谱. 由此表明, 噬菌体抗体芯片可用于识别细胞表面蛋白. 相似文献
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Lexun Li Shuang Liu Chunjuan Zhang Zhenzhen Guo Shuxuan Shao Xiaodan Deng Prof. Qiaoling Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(69):e202202070
Due to its excellent programmability and biocompatibility, DNA molecule has unique advantages in cell surface engineering. Recent progresses provide a reliable and feasible way to engineer cell surfaces with diverse DNA molecules and DNA nanostructures. The abundant form of DNA nanostructures has greatly expanded the toolbox of DNA-based cell surface engineering and gave rise to a variety of novel and fascinating applications. In this review, we summarize recent advances in DNA-based cell surface engineering and its biological applications. We first introduce some widely used methods of immobilizing DNA molecules on cell surfaces and their application features. Then we discuss the approaches of employing DNA nanostructures and dynamic DNA nanotechnology as elements for creating functional cell surfaces. Finally, we review the extensive biological applications of DNA-based cell surface engineering and discuss the challenges and prospects of DNA-based cell surface engineering. 相似文献
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Effect of Surface Protonation on Device Performance and Dye Stability of Dye-sensitized TiO2 Solar Cell
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A flat thin TiO2 film was employed as the photo-electrode of a dye sensitized solar cell (DSSC), on which only a geometrical mono-layer of dye was attached. The effect of sur-face protonation by HCl chemical treatment on the performance of DSSCs was studied. The results showed that the short-circuit current Jsc increased significantly upon the HCl treatment, while the open-circuit voltage Voc decreased slightly. Compared to the untreated DSSC, the Jsc and energy conversion efficiency was increased by 31% and 25%, respectively, for the 1 mol/L HCl treated cell. TiO2 surface protonation improved electronic coupling between the chemisorbed dye and the TiO2 surface, resulting in an enhanced electron in-jection. The decreased open-circuit voltage after TiO2 surface protonation was mainly due to the TiO2 conduction band edge downshift and was partially caused by increased electron recombination with the electrolyte. In situ Raman degradation study showed that the dye stability was improved after the TiO2 surface protonation. The increased dye stability was contributed by the increased electron injection and electron back reaction with the electrolyte under the open-circuit condition. 相似文献
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Chihiro Tanaka Takuro Kobori Mayuka Tameishi Yoko Urashima Takuya Ito Tokio Obata 《Molecules (Basel, Switzerland)》2021,26(18)
Cancer cells employ programmed cell death ligand-1 (PD-L1), an immune checkpoint protein that binds to programmed cell death-1 (PD-1) and is highly expressed in various cancers, including cervical carcinoma, to abolish T-cell-mediated immunosurveillance. Despite a key role of PD-L1 in various cancer cell types, the regulatory mechanism for PD-L1 expression is largely unknown. Understanding this mechanism could provide a novel strategy for cervical cancer therapy. Here, we investigated the influence of ezrin/radixin/moesin (ERM) family scaffold proteins, crosslinking the actin cytoskeleton and certain plasma membrane proteins, on the expression of PD-L1 in HeLa cells. Our results showed that all proteins were expressed at mRNA and protein levels and that all ERM proteins were highly colocalized with PD-L1 in the plasma membrane. Interestingly, immunoprecipitation assay results demonstrated that PD-L1 interacted with ERM as well as actin cytoskeleton proteins. Furthermore, gene silencing of ezrin, but not radixin and moesin, remarkably decreased the protein expression of PD-L1 without affecting its mRNA expression. In conclusion, ezrin may function as a scaffold protein for PD-L1; regulate PD-L1 protein expression, possibly via post-translational modification in HeLa cells; and serve as a potential therapeutic target for cervical cancer, improving the current immune checkpoint blockade therapy. 相似文献
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Nan Yan Yan Gao Junjie Yang Zhimin Fang Jiangshan Feng Prof. Xiaojun Wu Prof. Tao Chen Prof. Shengzhong Liu 《Angewandte Chemie (International ed. in English)》2023,62(11):e202216668
Wide-band gap (1.68 eV) perovskite solar cells (PSCs) are important components of perovskite/Si tandem devices. However, the efficiency of wide band gap PSCs has been limited by their huge open-circuit voltage (Voc) deficit due to non-radiative recombination. Deep-level acceptor defects are identified as the major killers of Voc, and they can be effectively improved by passivation with ammonium salts. Theoretical calculation predicts that increasing the distance between F and −NH3+ of fluorinated ammonium can dramatically enhance the electropositivity of −NH3+ terminals, thus providing strong adsorption onto the negatively charged IA and IPb anti-site defects. Characterizations further confirm that surface gradient passivation employing p-FPEAI demonstrates the most efficient passivation effect. Consequently, a record-efficiency of 21.63 % with the smallest Voc deficit of 441 mV is achieved for 1.68 eV-band gap inverted PSCs. Additionally, a flexible PSC and 1 cm2 opaque device also deliver the highest PCEs of 21.02 % and 19.31 %, respectively. 相似文献
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硒是人体必需的一种微量元素, 本课题组近年的研究表明含硒化学键具有诸多独特的化学性质. 二硒键具有氧化还原双重响应性, 同时是一类光响应的动态共价键, 能够在可见光辐照下发生可逆的交换反应. 将含硒化学键这些独特的性质与表界面化学相结合可以赋予体系独特的响应行为. 本文综合评述了本课题组近年来在含硒表界面化学领域的研究进展: 采用单分子力谱揭示了含硒化学键相互作用的力学规律; 通过表界面化学实现了二硒键动态平衡的调控; 基于二硒键氧化还原及可见光响应性实现了表界面可逆修饰、 二维材料功能化及层层组装膜材料的制备, 在生物医用、 液体输运等领域具有潜在应用价值. 相似文献
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Visualization of tumor-specific protein biomarkers on cell membranes has the potential to contribute greatly to basic biological research and therapeutic applications. We recently reported a unique supramolecular strategy for specific protein detection using self-assembling fluorescent nanoprobes consisting of a hydrophilic protein ligand and a hydrophobic BODIPY fluorophore in test tube settings. This method is based on recognition-driven disassembly of the nanoprobes, which induces a clear turn-on fluorescent signal. In the present study, we have successfully extended the range of applicable fluorophores to the more hydrophilic ones such as fluorescein or rhodamine by introducing a hydrophobic module near the fluorophore. Increasing the range of available fluorophores allowed selective imaging of membrane-bound proteins under live cell conditions. That is, overexpressed folate receptor (FR) or hypoxia-inducible membrane-bound carbonic anhydrases (CA) on live cell surfaces as cancer-specific biomarkers were fluorescently visualized using the designed supramolecular nanoprobes in the turn-on manner. Moreover, a cell-based inhibitor-assay platform for CA on a live cell surface was constructed, highlighting the potential applicability of the self-assembling turn-on probes. 相似文献