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The graphene family of nanomaterials (GFN) have a common carbon lattice base structure but represent a diverse range of materials with distinct chemical and physical characteristics. These characteristics are determined by the fabrication method and impart each material with specific chemical properties which govern interaction with cells and biomolecules, and physical properties that give unique nanotopography, stiffness, and electrical properties. Remarkably, members of the GFN have been shown to promote tissue formation and influence cell differentiation in a variety of tissue types, including neural, bone, and cardiac muscle, making them of high interest to the biomedical field. The diverse range of materials and experimental setups in the literature make uncovering the mechanism of action challenging. Nevertheless, it is becoming clear that the ability of GFN to form non-covalent interactions (π-π, hydrogen bonding, electrostatic) with biomolecules may increase their bioavailability via sequestering/concentration/conformation protection to induce cell differentiation. In addition to the chemical properties, the stimulation of mechanosensing pathways, cytoskeletal rearrangement, and enhanced electrical activity of cells on GFN substrates demonstrates the importance of the physical properties in directing cell differentiation. The understanding of the mechanism behind the ability of GFN to enhance cell differentiation will allow the design and selection of materials with the desired properties for tissue repair and regeneration. 相似文献
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We put forward the idea of building a molecular simulation experiment course. After two-year teaching practice, we write the experiment textbook which not only covers the classic experimental projects, but also includes the frontier hot issues, and open exploration experiment. This article summarizes the teaching requirements, basic content, assessment methods, the initial achievements made so far and the prospects for the future. 相似文献
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介绍成立浙江省高校化学化工实验教学中心联席会(以下简称:联席会)、举办化学学科(实验)竞赛的背景及发展情况。以联席会和竞赛为载体,建立了全省实验教学研究与改革的交流平台,扩大了实验教学示范中心的影响力和辐射面,推动了实验室建设、课程建设以及人才培养等各项工作,取得了丰硕的教学成果。 相似文献
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Asialoglycoprotein receptor (ASGPR) is one of the recognition motifs on the surface of hepatocytes, which promote their adhesion to extracellular matrix in liver tissue and appropriate artificial surfaces. ASGPR-mediated adhesion is expected to minimize trans-differentiation of hepatocytes in vitro that is generally observed in integrin-mediated adhesion. The aim of the present study is to verify the role of ASGPR in hepatocyte adhesion and proliferation in scaffolds for hepatic tissue engineering. Scanning Electrochemical Microscopy (SECM) is emerging as a suitable non-invasive analytical tool due to its high sensitivity and capability to correlate the morphology and activity of live cells. HepG2 cells and rat primary hepatocytes cultured in Polyvinyl alcohol (PVA)/Gelatin hydrogel scaffolds with and without galactose (a ligand for ASGPR) modification are studied using SECM. Systematic investigation of live cells cultured for different durations in scaffolds of different compositions (9:1 and 8:2 PVA:Gelatin with and without galactose) reveals significant improvement in cell–cell communication and proliferation on galactose incorporated scaffolds, thereby demonstrating the positive influence of ASGPR-mediated adhesion. In this work, we have also developed a methodology to quantify the respiratory activity and intracellular redox activity of live cells cultured in porous tissue engineering scaffolds. Using this methodology, SECM results are compared with routine cell culture assays viz., MTS ((1-Oxyl-2,2,5,5,-tetramethyl-Δ3-pyrroline-3-methyl) Methanethiosulfonate) and Albumin assays to demonstrate the better sensitivity of SECM. In addition, the present study demonstrates SECM as a reliable and sensitive tool to monitor the activity of live cells cultured in scaffolds for tissue engineering, which could be used on a routine basis. 相似文献
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Cell cycle regulates proliferative cell capacity under normal or pathologic conditions, and in general it governs all in vivo/in vitro cell growth and proliferation processes. Mathematical simulation by means of reliable and predictive models represents an important tool to interpret experiment results, to facilitate the definition of the optimal operating conditions for in vitro cultivation, or to predict the effect of a specific drug in normal/pathologic mammalian cells. Along these lines, a novel model of cell cycle progression is proposed in this work. Specifically, it is based on a population balance (PB) approach that allows one to quantitatively describe cell cycle progression through the different phases experienced by each cell of the entire population during its own life. The transition between two consecutive cell cycle phases is simulated by taking advantage of the biochemical kinetic model developed by Gérard and Goldbeter (2009) which involves cyclin-dependent kinases (CDKs) whose regulation is achieved through a variety of mechanisms that include association with cyclins and protein inhibitors, phosphorylation–dephosphorylation, and cyclin synthesis or degradation. This biochemical model properly describes the entire cell cycle of mammalian cells by maintaining a sufficient level of detail useful to identify check point for transition and to estimate phase duration required by PB. Specific examples are discussed to illustrate the ability of the proposed model to simulate the effect of drugs for in vitro trials of interest in oncology, regenerative medicine and tissue engineering. 相似文献
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Development of a liquid chromatography with mass spectrometry method for the determination of gelsemine in rat plasma and tissue: Application to a pharmacokinetic and tissue distribution study 下载免费PDF全文
Shuangshuang Zhang Shuping Hu Xiangxiang Yang Jiaqi Shen Xiaoyong Zheng Kexin Huang Zheng Xiang 《Journal of separation science》2015,38(6):936-942
Gelsemine from Gelsemium elegans Benth is a potential anesthetic and analgesic agent with no physical dependence and opiate addiction. This study was aimed at developing an ultrafast liquid chromatography coupled to tandem mass spectrometry method to quantify gelsemine in rat plasma and tissues. Plasma and tissues were processed with acetonitrile precipitation, and dendrobine was chosen as the internal standard. Sample separation was performed on an ACQUITY HSS T3 column. The mobile phase consisted of acetonitrile and 0.1% formic acid aqueous solution. Multiple reactions monitoring mode was utilized to detect the compounds of interest. The mass spectrometer was operated in the positive ion mode for detection. The MS/MS ion transitions monitored were m/z 323.2→70.5 for gelsemine and 264.2→108.05 for dendrobine, respectively. The calibration curves were linear over the range of 1–500 ng/mL in all biological matrices. The lower limit of quantification for rats plasma and tissues was 1.0 ng/mL. The values for inter‐ and intraday precision and accuracy were well within the ranges acceptable (< 15%). It was successfully applied to the pharmacokinetic and tissue distribution studies of gelsemine after intravenous doses of 5, 2, and 0.5 mg/kg in rats. These data of gelsemine would be useful for clinical application and further development. 相似文献
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以高三复习课“平衡原理的应用”为例,通过真实情境的剖析让学生感知模型,引导学生分析归纳提炼模型,并进行针对练习运用模型,变式训练体会模型,让学生在实践中以模型思维为突破,深入领悟建构模型的实质,有序解决复杂化学问题,提升科学思维能力,发展化学学科核心素养。 相似文献