低强度脉冲超声的骨骼肌修复效应及生物学机制研究*

骨骼肌是保持人体姿态和运动机能的重要组织器官。大量研究采用低强度脉冲超声治疗骨折、骨不连、肌腱和韧带损伤等并取得了较好的效果。然而应用低强度脉冲超声进行肌肉相关疾病治疗的研究相对较少,详细的机制仍不确定。该文综合相关研究报道,介绍了应用低强度脉冲超声进行肌肉修复的生物效应和细胞、肌细胞因子和细胞内信号转导通路的超声作用机制的研究现状。对现有研究存在的问题做了分析,并对肌肉组织损伤的超声治疗和对抗的研究方向进行了展望。     

三维拉曼成像技术用于纳米金刚石与细胞相互作用过程的研究

纳米金刚石(NDs),作为一种具备良好生物兼容性、化学稳定性、药物负载能力和众多不可比拟优越性能的材料,其在生物医学领域的应用被广泛关注,尤其是在生物成像和抗癌药物传输领域。首先对不同尺寸纳米金刚石的拉曼性能进行评价,确定了100 nm高温高压合成的NDs更适宜作为拉曼生物探针。之后,为了生物领域的应用,这些NDs表面的杂质经过羧基化方式处理获得均一表面性能,并采用扫描电镜、红外、拉曼和粒径分析手段对该过程进行验证。然后,NDs作为拉曼探针被用于快速定位HeLa细胞内NDs的分布,验证了HepG2细胞对NDs内吞过程的时间依赖性。此外,借助非侵入性的三维(3D)共聚焦拉曼成像技术,可视化观察了四种不同细胞(HeLa, HepG2, C6和MDCK)对NDs内吞量和滞留量的差异。其中,MDCK这种正常细胞内部极少发现NDs,而其他三种癌细胞中有大量NDs信号,显示出不同种类细胞对于NDs的吞入和滞留量的明显差异。实验结果表明,纳米金刚石拉曼生物探针不仅可以用于生物成像,更为癌症的定位和诊断提供可能性。     

Functionalization of hydrogen-free diamond-like carbon films using open-air dielectric barrier discharge atmospheric plasma treatments

A dielectric barrier discharge (DBD) technique has been employed to produce uniform atmospheric plasmas of He and N₂ gas mixtures in open air in order to functionalize the surface of filtered-arc deposited hydrogen-free diamond-like carbon (DLC) films. XPS measurements were carried out on both untreated and He/N₂ DBD plasma-treated DLC surfaces. Chemical states of the C 1s and N 1s peaks were collected and used to characterize the surface bonds. Contact angle measurements were also used to record the short- and long-term variations in wettability of treated and untreated DLC. In addition, cell viability tests were performed to determine the influence of various He/N₂ atmospheric plasma treatments on the attachment of osteoblast MC3T3 cells. Current evidence shows the feasibility of atmospheric plasmas in producing long-lasting variations in the surface bonding and surface energy of hydrogen-free DLC and consequently the potential for this technique in the functionalization of DLC-coated devices.     

Modified total intensity ratio methods for measuring cell gap of twisted nematic liquid crystal cells

This paper modifies the total intensity ratio method (TIRM) used to measure the cell gap of twisted nematic liquid crystal (TNLC) cells. Compared to the conventional TIRM in which a mechanical mechanism is used to physically rotate the polarizer, the modified TIRM methods presented in this study measure the total intensity ratio using a polarization rotation modulator. Two modified measurement methods are introduced. In the first, the saw-tooth signal applied to the electro-optic (EO) modulator is used as a reference signal in order to determine the polarization state of the measured signal. In the second method, a beam splitter and an additional quarter wave plate are added to the optical configuration. The quarter wave plate is adjusted such that a phase-matching condition is obtained between the reference and measured signals. The experimental results confirm that the modified TIRM approaches yield comparable accuracy to the conventional TIRM. Furthermore, in the proposed approaches, sufficient intensity signals to determine the cell gap can be obtained in just 2 s.     

A dynamic cellular vertex model of growing epithelial tissues

Intercellular interactions play a significant role in a wide range of biological functions and processes at both the cellular and tissue scales, for example, embryogenesis, organogenesis, and cancer invasion. In this paper, a dynamic cellular vertex model is presented to study the morphome-chanics of a growing epithelial monolayer. The regulating role of stresses in soft tissue growth is revealed. It is found that the cells originating from the same parent cell in the monolayer can orchestrate into clustering patterns as the tis-sue grows. Collective cell migration exhibits a feature of spatial correlation across multiple cells. Dynamic intercel-lular interactions can engender a variety of distinct tissue behaviors in a social context. Uniform cell proliferation may render high and heterogeneous residual compressive stresses, while stress-regulated proliferation can effectively release the stresses, reducing the stress heterogeneity in the tissue. The results highlight the critical role of mechanical factors in the growth and morphogenesis of epithelial tissues and help understand the development and invasion of epithelial tumors.     

磁性微球的制备及在细胞分离中的应用

总结评述了近年来磁性微球制备的研究工作,阐述了磁性微球用于细胞分离的基本原理和方法,指出了当前需要解决的问题。     

一种基于查尔酮衍生物的荧光探针对巯基氨基酸的检测及细胞成像

生物硫醇(如半胱氨酸(Cys)、同型半胱氨酸(Hcy)及谷胱甘肽(GSH))与生物体和细胞中的许多生理和病理过程密切相关。荧光探针是对生物硫醇灵敏检测与成像的有力工具。本文合成了一种可检测生物硫醇的基于2′-羟基查尔酮荧光团开启型荧光探针1。探针中的2,4-二硝基苯磺酸酯基团既作为反应识别基团,又作为荧光猝灭基团。在DMSO/Tris(体积比8/2,pH=8.4)中,探针1与生物硫醇反应后释放出前体化合物3,3具有激发态分子内质子转移(ESIPT)和聚集诱导发光(AIE)特性,从而导致长波长荧光发射及较大的斯托克斯位移。探针1具有合成简单、灵敏度高、选择性高、细胞毒性低等优点,可以方便地检测溶液和活细胞中的生物硫醇。     

基于分布式布拉格反射镜微腔的红绿蓝聚合物发光电化学池高色纯度光源

基于高色纯度的光源的显示技术具备宽色域、高色彩饱和度和高对比度的特点,能够给人们带来更好的视觉体验。近年来窄带宽光源的研制受到越来越多学者的关注。本文选择了三种典型的发光聚合物构筑聚合物发光电化学池(PLEC),利用分布式布拉格反射镜(DBR)和铝薄膜为腔对出射光谱进行窄化。结果表明,红绿蓝三色聚合物发光电化学池出射光的带宽可缩短至10、11和8 nm,色纯度得到了极大的提升。这种高色纯度光源的获得有望显著推动下一代显示技术的发展。     

Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation

The title compound N-2-thiophenesulfonyl-α-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, 1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the inhibitory rate of the title compound on K562 cells (chronic myeloid 1eukemic cells) was measured and the result of preliminary bioassay showed that the title compound possesses antiproliferation effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data: C15H17NO4S2, Mr = 339.42, monoclinic, space group P21, flack = –0.15(12), a = 5.7916(10), b = 11.5078(19), c = 12.924(2) , β = 97.781(3)o, Z = 2, V = 853.4(2) 3, Dc = 1.321 g/cm3, F(000) = 356, –7≤h≤7, –10≤k≤14, –15≤l≤15, R = 0.0628, wR = 0.1540 and μ(MoKα) = 0.327 mm-1. The molecule comprises a benzene and a thiofuran rings, and the intramolecular N(1)–H(1A)…O(1) makes a five-membered ring of O(1)–C(6)–C(5)–N(1)–H(1A).     

磁性高分子微球

对磁性高分子微球的研究现状进行了综述,详细探讨了目前常用的各种合成制备方法,并对各种方法的优缺点进行了分析。在此基础上,对磁性高分子微球在细胞分离、有机合成、环境/食品微生物检测等领域的最新应用进展及存在的问题进行了分析,指出了该领域今后的研究方向。