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壳聚糖与茜素红相互作用的电化学研究 总被引:4,自引:0,他引:4
生物活性大分子蛋白质、DNA及多糖等与小分子探针间的相互作用及其机理是近年来化学、临床医学及生命科学中研究的热点之一,这些研究可用于生物大分子的检测和新药的研发,壳聚糖(CS)是目前自然界已被发现的唯一带正电荷的可食用的碱性多糖,分子中含有丰富的氨基和羟基,并具有双螺旋结构,近年来已在食品、医药保健、化妆、环保、农业及化学化工等领域得到广泛应用, 相似文献
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蛋白质相互作用在生命活动中起着重要作用. 研究蛋白质间相互作用的本质有助于了解生命活动中这些基本单元的作用. 本文主要综述了近期蛋白质相互作用研究的进展, 包括蛋白质相互作用界面的基本性质, 蛋白质结合自由能的计算方法, 不同相互作用在蛋白质结合/解离中的角色和差异, 以及上述知识在蛋白质相互作用设计中的应用. 蛋白质相互作用界面的特性, 例如界面大小、保守性以及结构的动态性质, 使得具有生物功能的蛋白质相互作用界面区别于非特异性的晶体堆积界面. 生物功能界面的一个重要结构特征是界面上存在着关键残基以及相对独立的相互作用模块. 利用多种方法, 如MM-PBSA、统计平均势以及不同的相互作用自由能模型, 可以在不同的精度上计算蛋白质相互作用自由能. 利用蛋白质相互作用界面的特点, 从不同的角度进行蛋白质相互作用对的设计与改造, 近年来已经有了不少成功的例子, 但还存在着很大的挑战. 我们认为在今后的蛋白质相互作用设计中, 考虑各种因素对蛋白质结合与解离的动力学过程的影响将有助于提高人类控制蛋白质相互作用的能力. 相似文献
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药物缓释载体用温敏性水凝胶 总被引:1,自引:0,他引:1
近年来温敏性水凝胶作为药物缓释载体的研究十分广泛。本文在简要介绍了温敏性水凝胶的结构与性质、蛋白质的包埋技术和释药机理后,较为详细地综述了温敏性水凝胶在药物控制释放领域中的应用情况。 相似文献
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分子间相互作用在生物和材料等科学中发挥着关键作用,研究分子间相互作用的本质意义重大。氢键是分子间相互作用的一种主要形式,在确定分子构象和晶体结构以及生物分子尤其是核酸和蛋白质的结构功能中起着重要作用[1-3]。苯甲酸衍生物广泛存在于生物大分子内,与生物活性离子通过氢键作用等改变生物活性分子的活性功能,研究苯甲酸衍生物分子间氢键相互作用对于了解生物体内的化学现象具有重要意义。研究表明菱角的抗肿瘤作用明显,实验上已经从菱角中成功提取了活性单体化合物:3,4,5-三羟基苯甲酸二聚体[4],理论研究标题化合物的氢键结构与氢… 相似文献
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骨形态发生蛋白-2(BMP-2)的缓释载体一直是骨组织工程中的研究热点.本研究通过化学改性制备了两种肝素化丝素支架,并浸渍吸附BMP-2,研究了BMP-2在不同丝素支架样品上的吸附能力、体外释放性能及其对人骨肉瘤细胞MG-63碱性磷酸酶活性(ALP)的影响.结果表明,肝素化丝素支架对BMP-2具有较强的吸附能力,并能保持其体外缓慢释放性能;MG-63细胞在肝素化支架上生长状态良好,并具有显著的增殖能力,负载BMP-2后的肝素化支架能显著促进MG-63细胞的分化.因此,肝素化丝素支架是一种较理想的BMP-2缓释载体. 相似文献
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Masters KS 《Macromolecular bioscience》2011,11(9):1149-1163
Growth factors play a critical role in regulating processes involved in cellular differentiation and tissue regeneration, and are therefore considered essential elements in many tissue engineering strategies. The covalent immobilization of growth factors to biomaterial matrices addresses many of the challenges associated with delivering freely-diffusible growth factors and has thus emerged as a promising method of achieving localized and sustained growth factor delivery. This Feature Article discusses methods that have been used to immobilize growth factors to substrates, followed by an overview of several tissue repair and regeneration applications in which immobilized growth factors have been used. 相似文献
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Daisy M. Ramos Sama Abdulmalik Michael R. Arul Swetha Rudraiah Cato T. Laurencin Augustus D. Mazzocca Sangamesh G. Kumbar 《先进技术聚合物》2019,30(5):1205-1215
Use of growth factors as biochemical molecules to elicit cellular differentiation is a common strategy in tissue engineering. However, limitations associated with growth factors, such as short half‐life, high effective physiological doses, and high costs, have prompted the search for growth factor alternatives, such as growth factor mimics and other proteins. This work explores the use of insulin protein as a biochemical factor to aid in tendon healing and differentiation of cells on a biomimetic electrospun micro‐nanostructured scaffold. Dose response studies were conducted using human mesenchymal stem cells (MSCs) in basal media supplemented with varied insulin concentrations. A dose of 100‐ng/mL insulin showed increased expression of tendon markers. Synthetic‐natural blends of various ratios of polycaprolactone (PCL) and cellulose acetate (CA) were used to fabricate micro‐nanofibers to balance physicochemical properties of the scaffolds in terms of mechanical strength, hydrophilicity, and insulin delivery. A 75:25 ratio of PCL:CA was found to be optimal in promoting cellular attachment and insulin immobilization. Insulin immobilized fiber matrices also showed increased expression of tendon phenotypic markers by MSCs similar to findings with insulin supplemented media, indicating preservation of insulin bioactivity. Insulin functionalized scaffolds may have potential applications in tendon healing and regeneration. 相似文献
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We investigated the use of heparinized cellulose matrices (H-CM) as affinity substrates for binding of basic fibroblast growth
factor (bFGF), a heparin-binding peptide, to facilitate cellular proliferation and substrate-mediated transgene delivery.
Using human HT-1080 fibroblasts and Saos-2 osteoblasts as cellular models, we showed that H-CM was a friendly substrate for
cellular adhesion. Once adhered, cells received stimulation from the bound bFGF, leading to enhanced proliferation. Furthermore,
taking advantage of the negative zeta potential of H-CM, we applied electrostatic adsorption to immobilize cationic poly-ethylenimine/DNA
polyplexes onto the surface for transgene delivery upon cellular adhesion. Because bFGF stimulated cellular proliferation,
we observed a significant increase in transfection efficiency in comparison to transfection on H-CM without the bFGF binding.
We showed that H-CM was capable of mediating both bFGF peptide and bFGF transgene delivery to induce a synergistic stimulation
of cellular proliferation, thus offering a useful device for fabrication of tissue scaffolds. 相似文献
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In this study, we fabricated non‐woven matrices using blends of polycaprolactone and gelatin with various spinning volumes to control the immobilized heparin content, which was ultimately intended to increase the immobilization efficiency of bFGF. The amount of bFGF on the heparin conjugated fibrous matrices depended on the thicknesses of the swollen matrices ranging from 35.4 ± 6.5 to 162.3 ± 14.0 ng and ≈90% of the bFGF was gradually released over a period of up to 56 d. The released bFGF enhanced the proliferation of human umbilical vein endothelial cells and human mesenchymal stem cells. In conclusion, our heparin‐conjugated fibrous matrices have the potential to be used as a growth factor delivery system in tissue engineering applications.
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A robust flow injection (FI) on-line dilution system based on micro-sample introduction was developed for flame atomic absorption spectrometry (FAAS). Two computer programmed and stepper-motor driven syringe pumps were used for the precise and reproducible sample metering in micro-liters and carrier delivery. Factors, which might influence the performance of the system, such as sample matrix and carryover, were investigated. No inferior effects were observed with various matrices including 10% glycerol. Sample carryover effects were less than 0.4%, tested by analyzing a blank and a sample alternately. Dilution factors were decided and keyed in manually. The system was calibrated using a set of concentrated standard solutions for a given dilution factor. At a sampling frequency of 60 h−1, precisions were better than 2% R.S.D. (n=40) for dilution factors of 10-2000. The long-term stability of the system was examined by continuously running the system for a whole working day, and a precision of 2.6% R.S.D. (n=345) was obtained at a dilution factor of 1000. The system was verified by analyzing a standard copper alloy with a certified concentration of 57.4% Cu, resulting in a measurement solution with 574 mg l−1 Cu. 相似文献
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Aline Staub Sylvain Giraud Martial Saugy Serge Rudaz Jean‐Luc Veuthey Julie Schappler 《Electrophoresis》2010,31(2):388-395
CE is a powerful analytical tool used to separate intact biomolecules such as proteins. The coupling of CE with TOF/MS produces a very promising method that can be used to detect and identify proteins in different matrices. This paper describes an efficient, rapid, and simple CE‐ESI‐TOF/MS procedure for the analysis of endogenous human growth hormone and recombinant human growth hormone without sample preparation. Operational factors were optimized using an experimental design, and the method was successfully applied to distinguish human growth hormone and recombinant human growth hormone in unknown samples. 相似文献
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Bhattacharyya S Gonzalez M Robertson JD Bhattacharya R Mukherjee P 《Chemical communications (Cambridge, England)》2011,47(30):8530-8532
A simple synthesis of a targeted drug delivery system with enhanced cytotoxicity to (epidermal growth factor receptor) EGFR(+) cancer cells. 相似文献
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《Analytical letters》2012,45(14):2066-2074
Exogenous gene delivery may activate the immune system to generate the corresponding antibody; however, it is unknown whether all of the exogenous genes can induce such immune responses at the same level, and the result of simultaneous delivery of two or more genes is also unknown. To address the question, ELISA was used to determine antibody titers in serum against the most frequent gene doping such as growth hormone (GH), insulin-like growth factor α (IGF-α), and mechano growth factor (MGF), which were delivered into mice by naked vectors. There was no antibody against GH when saline, pCI-neo, or the pCI-GH plasmid alone was injected, but significant antibody was induced when the pCI-GH plasmid was injected in combination with either pCI-MGF or pCI-IGF-I plasmid (p < 0.05). Therefore, not all of exogenous genes can induce such immune response or the induced intensity is different, and multi-gene delivery was more likely than single gene to stimulate the immune system, which may be a potential method to detect gene doping. 相似文献
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《Solid State Sciences》2007,9(9):768-776
The research on controlled drug delivery systems using bioceramics as host matrices presents two distinct sides; one route aims at embedding pharmaceuticals in biomaterials designed for the reconstruction or regeneration of living tissues, in order to counteract inflammatory responses, infections, bone carcinomas and so forth, while the other route deals with the more traditional drug introduction systems, i.e. oral administration.The incorporation of pharmaceuticals to bioceramic matrices could be very interesting in clinical practice. It is rather common in these days for an orthopedic surgeon working in bone reconstruction to use bioceramics. An added value to the production of these ceramics would be the optional addition of pharmaceuticals such as antibiotics, anti-inflammatories, anti-carcinogens, etc. In this sense, if we take into account the infections statistics at hip joint prostheses, the incidence varies between 2 and 4%, reaching up to a 45% in bolts used as external fixation. One of the main problems in these situations is the access to the infected area of the bone, in order to deliver the adequate antibiotic. If the pharmaceutical could be included within the implant itself, the added value would be straightforward.And if the bioceramic is bioactive, and therefore precursor of new bone tissue, the capability to introduce peptides, proteins or growth factors at its pores could accelerate the bone regeneration processes. We are facing a fine example of multidisciplinary research, where the so-called transversal supply of knowledge from and between the domains of materials science, biology and medicine will empower the know-how and applications that shall, undoubtedly, give rise to new advances in science and technology. 相似文献
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Karine Modolon Zepon Luiz Fernando Vieira Valdir Soldi Gean Vitor Salmoria Luiz Alberto Kanis 《Polymer Testing》2013
Starch-cellulose acetate matrices containing silver sulfadiazine were produced using melt extrusion for application in drug delivery devices (DDDs). The influence of the extrusion parameters (screw speed and temperature) on the morphological and mechanical properties of the matrices was evaluated at three different levels. The microstructural characterization of all matrices showed that an increase in the screw speed enhances the porosity and drug dispersion, while an increase in the extrusion temperature decreases the pore diameter of the matrices. Mechanical results did not show significant differences between the elastic modulus values for the matrices; however, a faster screw speed led to higher ultimate strength and strain at failure values. Results obtained in the dynamic mechanical analysis showed that the glass transition and loss tangent (tan δ) peak values became higher with increasing screw speed and temperature. 相似文献