We describe the current plans for a spectroscopic survey of millions of stars in the Milky Way galaxy using the Guo Shou Jing Telescope （GSJT, formerly calledthe Large sky Area Multi-Object fiber Spectroscopic Telesc...We describe the current plans for a spectroscopic survey of millions of stars in the Milky Way galaxy using the Guo Shou Jing Telescope （GSJT, formerly calledthe Large sky Area Multi-Object fiber Spectroscopic Telescope -- LAMOST）. The survey will obtain spectra for 2.5 million stars brighter than r 〈 19 during dark/grey time, and 5 million stars brighter than r 〈 17 or J 〈 16 on nights that are moonlit or have low transparency. The survey will begin in the fall of 2012, and will run for at least four years. The telescope＇s design constrains the optimal declination range for observations to 10~ 〈 di 〈 50~, and site conditions lead to an emphasis on stars in the direction of the Galactic anticenter. The survey is divided into three parts with different target selection strategies： disk, anticenter, and spheroid. The resulting dataset will be used to study the merger history of the Milky Way, the substructure and evolution of the disks, the nature of the first generation of stars through identification of the lowest metallicity stars, and star formation through study of open clusters and OB associations. Detailed design of the LAMOST Experiment for Galactic Understanding and Exploration （LEGUE） survey will be completed in summer 2012, after a review of the results of the pilot survey.展开更多
Background Thioredoxin is one of the most important redox regulating proteins. Although thioredoxin has been shown to protect cells against different kinds of oxidative stress, the role of thioredoxin in myocardial is...Background Thioredoxin is one of the most important redox regulating proteins. Although thioredoxin has been shown to protect cells against different kinds of oxidative stress, the role of thioredoxin in myocardial ischemia and reperfusion injury has not been fully understood. This study was conducted to explore the protective role of human thioredoxin on myocardial ischemia and reperfusion injury and its potential mechanisms. Methods Purified human thioredoxin was injected into adult Wister rats, which were subjected to 30 minutes of myocardial ischemia followed by 2 or 24 hours of reperfusion. We detected 1） the infarct size; 2） the level of malondisldehyde （MDA） in serum; 3） the expression of caspase-9, and cytochrome c in/out of mitochondia by Western blotting; 4） apoptosis by terminal-deoxynucleotidyl transferase mediated nick end labeling （TUNEL） assay and caspase-3 and its protein by reverse transcriptase polymerase chain reaction （RT-PCR） and Western blotting; 5） the expression of bcl-2 and bax in cardium by immunohistochemical （IHC） assay. Results Human thioredoxin reduced myocardial ischemia/reperfusion injury as evidenced by significant decrease of myocardial infarct size （P〈0.01）, notable reduction of myocyte apoptosis （P 〈0.01）, lower systemic oxidative stress level （P 〈0.01） after reperfusion for 2 hours, and few inflammatory cell infiltration after reperfusion for 24 hours in rats. Furthermore, treatment with human thioredoxin significantly reduced the release of mitochonddal cytochrome C （P〈0.05） and inhibited the activity of caspase-9 （P 〈0.05） and caspase-3 （P 〈0.01 in mRNA and P 〈0.05 at protein level）. Meanwhile, human thioredoxin markedly increased bcl-2 expression （P 〈0.05）. Conclusions These results strongly suggest that human thioredoxin has cardioprotective effects on myocardial ischemia/reperfusion and its anti-apoptotic role may be mediated by modulating bcl-2 and the mitochondria-dependent apoptotic signaling pathway展开更多
基金partially supported by the National Natural Science Foundation of China (Grant Nos. 10573022, 10973015, 11061120454and 11243003)the US National Science Foundation through grant AST-09-37523
文摘We describe the current plans for a spectroscopic survey of millions of stars in the Milky Way galaxy using the Guo Shou Jing Telescope （GSJT, formerly calledthe Large sky Area Multi-Object fiber Spectroscopic Telescope -- LAMOST）. The survey will obtain spectra for 2.5 million stars brighter than r 〈 19 during dark/grey time, and 5 million stars brighter than r 〈 17 or J 〈 16 on nights that are moonlit or have low transparency. The survey will begin in the fall of 2012, and will run for at least four years. The telescope＇s design constrains the optimal declination range for observations to 10~ 〈 di 〈 50~, and site conditions lead to an emphasis on stars in the direction of the Galactic anticenter. The survey is divided into three parts with different target selection strategies： disk, anticenter, and spheroid. The resulting dataset will be used to study the merger history of the Milky Way, the substructure and evolution of the disks, the nature of the first generation of stars through identification of the lowest metallicity stars, and star formation through study of open clusters and OB associations. Detailed design of the LAMOST Experiment for Galactic Understanding and Exploration （LEGUE） survey will be completed in summer 2012, after a review of the results of the pilot survey.
文摘Background Thioredoxin is one of the most important redox regulating proteins. Although thioredoxin has been shown to protect cells against different kinds of oxidative stress, the role of thioredoxin in myocardial ischemia and reperfusion injury has not been fully understood. This study was conducted to explore the protective role of human thioredoxin on myocardial ischemia and reperfusion injury and its potential mechanisms. Methods Purified human thioredoxin was injected into adult Wister rats, which were subjected to 30 minutes of myocardial ischemia followed by 2 or 24 hours of reperfusion. We detected 1） the infarct size; 2） the level of malondisldehyde （MDA） in serum; 3） the expression of caspase-9, and cytochrome c in/out of mitochondia by Western blotting; 4） apoptosis by terminal-deoxynucleotidyl transferase mediated nick end labeling （TUNEL） assay and caspase-3 and its protein by reverse transcriptase polymerase chain reaction （RT-PCR） and Western blotting; 5） the expression of bcl-2 and bax in cardium by immunohistochemical （IHC） assay. Results Human thioredoxin reduced myocardial ischemia/reperfusion injury as evidenced by significant decrease of myocardial infarct size （P〈0.01）, notable reduction of myocyte apoptosis （P 〈0.01）, lower systemic oxidative stress level （P 〈0.01） after reperfusion for 2 hours, and few inflammatory cell infiltration after reperfusion for 24 hours in rats. Furthermore, treatment with human thioredoxin significantly reduced the release of mitochonddal cytochrome C （P〈0.05） and inhibited the activity of caspase-9 （P 〈0.05） and caspase-3 （P 〈0.01 in mRNA and P 〈0.05 at protein level）. Meanwhile, human thioredoxin markedly increased bcl-2 expression （P 〈0.05）. Conclusions These results strongly suggest that human thioredoxin has cardioprotective effects on myocardial ischemia/reperfusion and its anti-apoptotic role may be mediated by modulating bcl-2 and the mitochondria-dependent apoptotic signaling pathway
