CAGW and TAT‐NLS peptides functionalized multitargeting gene delivery system with high transfection efficiency

Gene therapy has attracted much attention in vascular tissue engineering. However, it is still challenging to develop a novel gene carrier with multifunction to overcome the barriers in gene delivery. Herein, the multitargeting gene complexes were developed based on methoxy‐poly(ethylene glycol)‐b‐poly‐(D,L‐lactide‐co‐glycolide) (mPEG‐b‐PLGA), poly(d ,l ‐lactide‐co‐glycolide)‐g‐polyethylenimine‐g‐CAGW (PLGA‐g‐PEI‐g‐CAGW), cell‐penetrating peptide YGRKKRRQRRR (TAT), nuclear localization signals (NLS), and pEGFP‐ZNF580 (pDNA) with the purpose of enhancing the transfection of endothelial cells (ECs). The low cytotoxic multitargeting gene complexes could be easily prepared by adjusting the weight ratio of mPEG‐b‐PLGA and PLGA‐g‐PEI‐g‐CAGW. Meanwhile, CAGW peptide with selectively ECs‐targeting ability and TAT‐NLS peptide sequence with both cell‐penetrating ability and nuclear targeting capacity were simultaneously introduced into gene complexes in order to enable them with the multitargeting function so as to improve their gene delivery capacity. The pDNA loading capacity of these gene complexes was confirmed by agarose gel electrophoresis assay. MTT results demonstrated that the relatively cell viability of the multitargeting gene complexes was higher than those of other groups. These multitargeting gene complexes showed higher internalization and transfection efficiencies than other groups. These results revealed that CAGW and TAT‐NLS peptide sequences benefited for efficient gene delivery. Furthermore, the wound healing assay demonstrated that the multitargeting gene complexes could promote the proliferation and migration of ECs. These results collectively demonstrated that CAGW and TAT‐NLS peptides functionalized gene delivery system could effectively enhance the transfection of ECs, which has great potential in vascular tissue engineering.     

π- d Interaction-Based Molecular Magnets: Role of Sulfur-to-Selenium Substitution

Abstract

The crystal structure and physical properties of the three conducting molecular magnets are discussed. (DMET)₂FeBr₄ is composed of alternating stacks of quasi-one-dimensional donor sheets and square lattice magnetic anion sheets. This salt undergoes an spin density wave (SDW) transition of the donor layer at 40 K and an antiferromagnetic transition of Fe³⁺ spins on the anion layer at 3.7 K. The one-to-one correspondence of the anomalies appearing on the magnetization curves with those on the magnetoresistance supports the presence of the π-d interaction. The all-sulfur analog (EDTDM)₂FeBr₄ shows, besides similar behaviors as the DMET salt, insulator-to-metal transition of the ground state by applying the pressure, accompanied with a large negative magnetoresistance. (EDS-TTF)₂FeBr₄ shows little π-d interaction despite the presence of close Se–Br contacts, showing the importance of the intermolecular orbital overlap between the π- and d-components.     

化学类本科综合化学实验教学的实践与思考

综合化学实验是联系基础化学实验和过渡到本科毕业论文专题研究的一个桥梁。本文根据笔者多年的设计型综合实验教学,概要阐述了综合化学实验教学中如何贯彻综合化学的基本特征,依照"教师引导,学生主体"的思想,帮助学生了解学科发展的前沿热点,锻炼查阅文献和阅读、提炼其实验精华、主动探究和学习的能力,以达到锻炼学生的实验操作能力和提高学生的整体素质。     

Non-isothermal crystallization kinetics of V2O5-MoO3-Bi2O3 glasses

Characteristic temperatures, such as T _g (glass transition), T _x (crystallization temperature) and T _l (liquidus temperature) of glasses from the V₂O₅-MoO₃-Bi₂O₃ system were determined by means of differential thermal analysis (DTA). The higher content of MoO₃ improved the thermal stability of the glasses as well as the glass forming ability. The non-isothermal crystallization was investigated and following energies of the crystal growth were obtained: glass #1 (80V₂O₅·20Bi₂O₃) E _G=280 kJ mol^-1, glass #2 (40V₂O₅·30MoO₃·30Bi₂O₃) E _G=422 kJ mol^-1 and glass #3 (80MoO₃·10V₂O₅·10Bi₂O₃) E _G=305 kJ mol^-1. The crystallization mechanism of glass #1 (n=3) is bulk, of glass #3 (n=1) is surface. Bulk and surface crystallization was supposed in glass #2. The presence of high content of a vanadium oxide acts as a nucleation agent and facilitates bulk crystallization. This revised version was published online in August 2006 with corrections to the Cover Date.     

A Multi-Strategy Adaptive Comprehensive Learning PSO Algorithm and Its Application

In this paper, a multi-strategy adaptive comprehensive learning particle swarm optimization algorithm is proposed by introducing the comprehensive learning, multi-population parallel, and parameter adaptation. In the proposed algorithm, a multi-population parallel strategy is designed to improve population diversity and accelerate convergence. The population particle exchange and mutation are realized to ensure information sharing among the particles. Then, the global optimal value is added to velocity update to design a new velocity update strategy for improving the local search ability. The comprehensive learning strategy is employed to construct learning samples, so as to effectively promote the information exchange and avoid falling into local extrema. By linearly changing the learning factors, a new factor adjustment strategy is developed to enhance the global search ability, and a new adaptive inertia weight-adjustment strategy based on an S-shaped decreasing function is developed to balance the search ability. Finally, some benchmark functions and the parameter optimization of photovoltaics are selected. The proposed algorithm obtains the best performance on 6 out of 10 functions. The results show that the proposed algorithm has greatly improved diversity, solution accuracy, and search ability compared with some variants of particle swarm optimization and other algorithms. It provides a more effective parameter combination for the complex engineering problem of photovoltaics, so as to improve the energy conversion efficiency.     

后疫情时代中学化学教师信息化教学能力评价

利用文献研究法从中学化学教学特点和教师有效教学等2个方面入手,构建了由信息化应用能力、信息化资源整合能力和信息化教学实施能力等3个一级指标和10个二级指标组成的中学化学教师信息化教学技能评价指标,采用结构方程模型路径系数确定了指标权重,构建出了中学化学教师信息化教学能力评价指标体系。通过实证研究表明,所构建的评价指标体系可操作性强,评价结果直观清晰,便于持续改进。     

新型可溶性酞菁铜（Ⅱ）衍生物的合成,结构及其成膜性

合成了两个新型取代酞菁铜(Ⅱ)衍生物:四-4-(2-甲氧基乙氧基-羰基)酞菁铜(Ⅱ)(A)和四-4-(2-正丁氧基乙氧基-羰基)酞菁铜(Ⅱ)(B),以元素分析、ESR、~1H NMR和FT-IR进行了表征。UV-vis光谱表明它们在氯仿溶液(10~(-5)～10(-6)mol/L)中主要以双分子缔合形式存在;X-射线粉末衍射表明配合物的分子以倾斜的方式相互平行排列;热重分析表明酞菁环引入有机基团后其热稳定性略有下降,且取代基越长,热稳定性越差。两个配合物的氯仿溶液在亚相(水)上的π-A曲线表明,它们均有明显的“气”液”“固”的变化过程,并能形成较好的单分子层膜。     

异质结光催化材料的新进展

伴随着人类文明的快速发展,一些危机慢慢显露出来,例如能源危机、环境污染和全球变暖.2019年5月11日,Mauna Loa天文台报告,大气中的二氧化碳水平超过415 ppm,达到人类历史上的最高记录,欧盟随后于2019年11月宣布了气候紧急状态.因此,绿色能源技术已成为迫切需求,以减少化石燃料的使用,并减少污染物的产生...     

分析化学自主设计实验的实践与探索:测定磁介质铁路客票中铁的含量*

介绍了一个自主设计实验“测定磁介质铁路客票铁的含量”,该实验设计选取生活中熟悉又“陌生”的铁路客票为研究对象,以经典验证型实验“无汞盐法测全铁”为理论和实验基础,学生自行查阅文献、设计实验方案、分析讨论方案,再进行具体实验探究,分析实验结果,并撰写小论文。该教学实验项目的实施能有效促进理论知识体系和实验操作技能的深度融合,提高学生的创新能力和综合素质。     

刚性4-取代双三唑配体构筑的三个锌配合物的合成和荧光

在室温下合成了3个新的配位聚合物{[Zn(4?Nbdc)(btx)]·2H₂O}_n(1·2H₂O)、[Zn(btx)_1.5(1,3?bdac)]n(2)和{[Zn(mbtx)(1,3?bdc)(H₂O)₂]·H₂O}_n(3)(btx=1,4?二(4H?1,2,4?三唑)苯,mbtx=1,3?二(4H?1,2,4?三唑)苯,4?Nbdc=4?硝基邻苯二甲酸根,1,3?bdac=间苯二乙酸根,1,3?bdc=间苯二甲酸根),测试了配合物的单晶结构,并从元素分析、红外和粉末衍射等方面进行表征。单晶X射线衍射表明,配合物1是二维(4,4)网格结构,配合物2和3都是一维链状结构。配合物2中的π?π作用将一维链连接成三维网格结构。在配合物3中,分子间氢键将一维链连接成二维网格,2套二维网格在分子间氢键的作用下相互穿插得到2D+2D→2D的网格结构。同时,还研究了3个配位聚合物的荧光和热稳定性。