Adsorption behavior of fetal bovine serum (FBS) onto hydroxyapatite (HAp) was analyzed in situ in phosphate buffer saline (PBS), minimum essential mediums (αMEM or DMEM), and different carbonate-concentrated buffers ...
详细信息
Designing magnetic shape memory materials with practicable engineering applications requires a thorough understanding of their electronic, magnetic, and mechanical properties. Experimental and computational studies on...
详细信息
Alumina ceramics in a wear test reacts with air humidity to form a film layer of aluminum hydroxide which acts as a lubricant. Increasing sliding test load and/or speed affects the tribofilm and changes the wear regim...
详细信息
Alumina ceramics in a wear test reacts with air humidity to form a film layer of aluminum hydroxide which acts as a lubricant. Increasing sliding test load and/or speed affects the tribofilm and changes the wear regime from mild to severe. The purpose of this work was to determine critical values of load and sliding speed for the wear regime transition under controlled atmosphere humidity, in a pin-on-disc test. The wear rate and the worn surface SEM image and roughness allowed to distinguish the mild and severe wear regime for different speed/load combinations so that the boundaries of mild wear region was determined. The boundaries were characterized by a narrow transition zone. The image analyses have shown distinct wear mechanisms as function of sliding speed and load.
Efficient phosphors based on YNbO4 and doped by Eu3+, Ga3+, Al3+ were synthesized and investigated under UV, and X-ray excitation in luminescence and Raman spectroscopy. Monoclinic fergusonite crystal structure and ex...
详细信息
Single walled carbon nanotubes (SWNT) have shown tremendous promise as agents for diagnostic and therapeutic intervention in vivo. We demonstrate how Dextran sulfate (DS) can render SWNT transparent to macrophages, a ...
详细信息
The aspartic protease cathepsin E has been shown to induce apoptosis in cancer cells under physiological conditions. Therefore, cathepsin E-activity-enhancing peptides functioning in the physiological pH range are val...
We compared cytotoxicities of metal oxide nanomaterials, including different sizes (20 and 60 nm) of ZnO nanoparticles (NPs), Al-doped ZnO-NPs, Al2O3-NPs, Al2O3 nanowhiskers (NWs) and SiO2-NPs, on the basis of viabili...
详细信息
We compared cytotoxicities of metal oxide nanomaterials, including different sizes (20 and 60 nm) of ZnO nanoparticles (NPs), Al-doped ZnO-NPs, Al2O3-NPs, Al2O3 nanowhiskers (NWs) and SiO2-NPs, on the basis of viabilities of human lung epithelial A549 cells exposed to these nanoma- terials. Al2O3-NPs, Al2O3-NWs and SiO2-NPs showed no significant cytotoxic effects on viability. On the other hand, ZnO-NPs, which included ZnO-NPs (20 nm), ZnO-NPs (60 nm), and Al-doped ZnO-NPs, all showed toxic effects;however, no significant differences in cytotoxicity were observed among these ZnO-NPs, suggesting that nanoparticle size and Al-doping do not contribute to cytotoxicity. Global gene expression analysis using a DNA microarray revealed that 22 and 8 genes were consistently up and down-regulated, respectively, in cells exposed to the 3 ZnO-NPs. Our results suggest that up-regulation of genes by ZnO-NPs leads to maintenance of zinc homeostasis and protection against oxidative stress, while down-regulation of genes causes disruption of zinc homeostasis, DNA damage, and apoptosis. The balance between protective mechanisms induced by up-regulated genes and cellular damages induced by down-regulated genes may determine the fate of cells.
暂无评论