Phospholipids are key components of cellular membrane and signaling. Among cellular phospholipids, phosphoinositides, phosphorylated derivatives of phosphatidylinositol are important as a participant in essential metabolic processes in animals. However, due to its low abundance in cells and tissues, it is difficult to identify the composition of phosphoinositides. Recent advances in mass spectrometric techniques, combined with established separation methods, have allowed the rapid and sensitive detection and quantification of a variety of lipid species including phosphoinositides. In this mini review, we briefly introduce progress in profiling of cellular phosphoinositides using mass spectrometry. We also summarize current progress of matrices development for the analysis of cellular phospholipids using matrix-assisted laser desorption/ionization mass spectrometry. The phosphoinositides profiling and phospholipids imaging will help us to understand how they function in a biological system and will provide a powerful tool for elucidating the mechanism of diseases such as diabetes, cancer and neurodegenerative diseases. The investigation of cellular phospholipids including phosphoinositides using electrospray ionization mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry will suggest new insights on human diseases, and on clinical application through drug development of lipid related diseases. 相似文献
The growth and self‐organization of organic crystals between a source (S) and drain (D) electrode by a method based on the use of a micropipette and isothermal evaporation of the solvent in a two‐liquid system led to the formation of organic‐crystal transistors (see polarized optical micrograph). The method is similar to ink‐jet printing and should be suitable for the fabrication of low‐cost and mass‐producible printed electronic devices.
In this study, we used the colloid probe atomic force microscopy (AFM) technique to investigate the adhesion force between a living cell and a silica colloid particle in a Leibovitz's L-15 medium (L-15). The L-15 liquid maintained the pharmaceutical conditions necessary to keep the cells alive in the outside environment during the AFM experiment. The force curves in such a system showed a steric repulsion in the compression force curve, due to the compression of the cells by the colloid probe, and an adhesion force in the decompression force curve, due to binding events between the cell and the probe. We also investigated for the first time how the position on the cell surface, the strength of the pushing force, and the residence time of the probe at the cell surface individually affected the adhesion force between a living cell and a 6.84 μm diameter silica colloid particle in L-15. The position of measuring the force on the cell surface was seen not to affect the value of the maximum adhesion force. The loading force was also seen not to notably affect the value of the maximum adhesion force, if it was small enough not to pierce and damage the cell. The residence time of the probe at the cell surface, however, clearly affected the adhesion force, where a longer residence time gave a larger maximum force. From these results, we could conclude that the AFM force measurements should be made using a loading force small enough not to damage the cell and a fixed residence time, when comparing results of different systems. 相似文献
ERCC1 is a DNA repair gene and has been associated with resistance to DNA damaging agents. In this study we hypothesized that a polymorphism of ERCC1 Asn118Asn (C -> T) might affect the platinum-resistance of epithelial ovarian cancer patients to platinum-taxane chemotherapy administered postoperatively. Using the SNapShot assay, we assessed this polymorphism in ERCC1 in 60 ovarian cancer patients. Platinum-resistance was defined as progression on platinum-based chemotherapy or recurrence within 6 months of completing therapy. Although not significant, platinum-resistance was less frequently observed in patients with the C/T+T/T genotype (P=0.064). Multivariate analysis showed that the C/T+T/T genotypes constituted an independent predictive factor of reduced risk of platinum-resistance in ovarian cancer (odds ratio 0.17, 95% confidence interval 0.04-0.74, P=0.018, Fisher's exact test). No significant correlation was observed between overall survival and the ERCC1 polymorphism. Our results suggest that genotyping of the ERCC1 polymorphism Asn118Asn may be useful for predicting the platinum-resistance of epithelial ovarian cancer patients. However, these findings require prospective confirmation. 相似文献
The diastereoselective synthesis of unsaturated aromatic 1,2-amino alcohols can be achieved on an epimeric mixture of optically active allylic ethers having a hydroxyl group attached to an allylic chiral center to the pi-system using chlorosulfonyl isocyanate. These reactions produced the unsaturated anti-1,2-amino alcohols either exclusively or predominantly only for aromatic derivatives. The anti-selectivity may be explained by the Cieplak electronic model during the conversion from ethers to carbamates. 相似文献