复频聚焦超声激活血卟啉杀伤肿瘤细胞K562的实验研究

为了研究单复频超声激活血卟啉对人体肿瘤细胞的杀伤效应，利用自制的复频聚焦换能器激活血卟啉，以肿瘤细胞K562：为研究对象，采用MTF法(四唑盐比色法)检测在不同超声处理时间、不同频率、不同溶液环境下、不同孵育时间条件下，声动力学激活血卟啉法对肿瘤细胞的杀伤效应。结果表明，复频聚焦超声激活血卟啉对肿瘤细胞具有较强的杀伤效应，是一种有应用前景的治疗肿瘤的新技术。  

声化学激活血卟啉对瘤细胞K562作用的研究

文章研究了超声激活血卟啉对人体肿瘤细胞K562的作用以及声辐照剂量和血卟啉浓度对瘤细胞杀伤率的影响。结果表明，声辐射剂量和血卟啉浓度和瘤细胞杀伤率呈正相关系。当频率为1．8MHz、声强度为1．5W／cm^2、作用时间为60s、血卟啉浓度为200μg／mL时，超声激活血卟啉对K562肿瘤作用效果较佳，杀伤率达98％，超声单独作用仅为42％，单纯血卟啉无抗肿瘤效应。  

Aptamer-conjugated upconversion nanoprobes assisted by magnetic separation for effective isolation and sensitive detection of circulating tumor cells

Detection of circulating tumor cells （CTCs） plays an important role in cancer diagnosis and prognosis. In this study, aptamer-conjugated upconversion nano- particles （UCNPs） are used for the first time as nanoprobes to recognize tumor cells, which are then enriched by attaching with magnetic nanoparticles （MNPs） and placing in the presence of a magnetic field. Owing to the autofluorescence- free nature of upconversion luminescence imaging, as well as the use of magnetic separation to further reduce background signals, our technique allows for highly sensitive detection and collection of small numbers of tumor cells spiked into healthy blood samples, and shows promise for CTC detection in medical diagnostics.  

Glucose-conjugated chitosan nanoparticles for targeted drug delivery and their specific interaction with tumor cells

A novel targeted drug delivery system, glucose-conjugated chitosan nanoparticles （GCNPs）, was developed for specific recognition and interaction with glucose transporters （Gluts） over-expressed by tumor cells. GC was synthesized by using succinic acid as a linker between glucosamine and chitosan （CS）, and successful synthesis was confirmed by NMR and elemental analysis. GCNPs were prepared by ionic crosslinking method, and characterized in terms of morphology, size, and zeta potential. The optimally prepared nanoparticles showed spherical shapes with an average particle size of （187.9 ± 3.8） nm and a zeta potential of （-15.43 ± 0.31） mV. The GCNPs showed negligible cytotoxicity to mouse embryo fibroblast and 4T1 cells. Doxorubicin （DOX） could be efficiently entrapped into GCNPs, with a loading capacity and encapsulation efficiency of 20.11% and 64.81%, respectively. DOX-Ioaded nanoparticles exhibited sustained-release behavior in phosphate buffered saline （pH 7.4）. In vitro cellular uptake studies showed that the GCNPs had better endocytosis ability than CSNPs, and the antitumor activity of DOX/GCNPs was 4-5 times effectiveness in 4T1 cell killing than that of DOX/CSNPs. All the results demonstrate that nanoparticles decorated with glucose have specific interactions with cancer cells via the recognition between glucose and Gluts. Therefore, Gluts-targeted GCNPs may be promising delivery agents in cancer therapies.  

探究饮食，体液酸碱度与肿瘤细胞酸性微环境之间的关系

由于机体可通过缓冲离子、肺和肾的调节，及细胞内外的离子交换等途径维持体液酸碱度（pH）在7．35—7．45的正常生理范围内），一般认为，即使食物进入人体产生大量的酸性产物，单纯饮食因素难以导致人体体液酸碱度的变化。所以，不良饮食习惯可导致酸碱性体质的学说一再受到质疑。但是，近些年大量文献证明，健康的饮食习惯可以预防、延缓、甚至遏制肿瘤细胞的生长和转移。有报道显示，肿瘤酸性微环境会诱导肿瘤细胞侵袭，转移和耐药。这些结果提示，饮食，体液酸碱度及肿瘤细胞酸性微环境之间可能存在一定的相关性。  

循环肿瘤细胞检测技术的发展现状及展望

循环肿瘤细胞(Circulating Tumor Cells,CTCs)存在于肿瘤患者外周血中,特异、敏感地检测CTCs对肿瘤患者的预后评价和临床的个体化治疗均有重要意义.该文在综述CTCs的富集、筛选和鉴定技术的基础之上,对微流控芯片技术在这一领域的应用做了重点阐述.  

Cytotoxic Effects of Biodegradation of Pure Mg and MAO-Mg on Tumor Cells of MG63 and KB

Magnesium （Mg） based metals possess unique features of biodegradation that can be used for different purposes. In this study, two tumor cells, MG63 and KB, were cultured directly on a pure Mg with and without MAO coating to evaluate their cytotoxic effects on the tumor cells. It was found that both MG63 cells and KB cells adhered better on the surface of the coated Mg samples than those on the pure Mg samples. However, the survivals of two kinds of tumor cells were obviously inhibited on both Mg samples with and without coating, compared with that on the pure titanium. In addition, the survival of MG63 cells was more susceptive to the Mg degradation compared with the KB cells. Thus, the application of such effect should take account of that the degradation of Mg based metal may result in different cytotoxic effect on different cells.  

Cytotoxic Effect on Osteosarcoma MG-63 Cells by Degradation of Magnesium

Biocompatible and biodegradable magnesium （Mg） based metals have attracted great interest for use in orthopedic implants and devices. Based on our previous study that Mg with and without micro-arc oxidation （MAO） coating showed obvious cytotoxic effect on tumor cells due to the increase of pH value during the degradation of Mg, this study further evaluated the cytotoxic effect of Mg and MAO coated Mg on osteosarcoma （MG-63） cells by analyzing the cell adhesion, morphology and number through observation of scanning electron microscope, as well as live/dead staining, lactate dehydrogenase （LDH） activity and 4, 6- diamidino-2-phenylindole （DAPI） assay. The results indicated that, compared to titanium, Mg could strongly inhibit the cell adherence, morphology and number of MG-63 on the surface of the naked Mg, whereas the MAO coated Mg showed relative weak cytotoxic effect on MG-63 cells, expecting that magnesium based metals with suitable coating can be designed to be applied as tumor prosthesis in the clinical practice.  

新型纳米芯片能检测罕见循环肿瘤细胞

正在一种新型纳米材料芯片的帮助下,诱发早期癌症患者体内癌症扩散的一类细胞能够被高灵敏地检测出来。《自然纳米技术》上的这项研究发现意味着,对这类细胞的分离与修复能够贯穿于癌症病人的诊断与治疗中。Sunitha Nagrath等人研发出一种基于石墨烯氧化物的芯片,该芯片能够捕捉一种罕见  

DNA“纳米火车”问世可输送抗癌药物

湖南大学化学生物传感与计量学国家重点实验室主任谭蔚泓带领课题组研发出一种能向肿瘤细胞靶向输送大量抗癌药物的DNA“纳米火车”．不仅可提高抗癌药物的靶向性，减少药物的毒副作用，还可大大增加药物的携带量。相关成果发表于美国《国家科学院院刊》。