Loss of function and gain of function mutations of the sodium channel were investigated using an intact two-dimensional rabbit sinoatrial node (SAN) and atrial cell model. The effects of three external stimuli (acetyl...Loss of function and gain of function mutations of the sodium channel were investigated using an intact two-dimensional rabbit sinoatrial node (SAN) and atrial cell model. The effects of three external stimuli (acetylcholine secretion by the vagal nerve, acid-base concentration, and tissue temperature) on cardiac pacemaker function and conduction were studied. Our results show that these two groups of mutations have different effects on pacemaker function and conduction. Furthermore, we found that the negative effects of these mutations could be altered by external stimuli. The bradycardic effects of mutations were magnified by an increase in acetylcholine level. Changes in acid-base concentration and tissue temperature increased the ability of the SAN to recover its pacemaker function. The results of this study increase our understanding of sodium channel disorders, and help to advance research on the treatment of these conditions.展开更多
By investigating a stochastic model for intracellular calcium oscillations proposed by Hfer,we have analyzed the transmission behavior of calcium signaling in a one-dimensional two-way coupled hepatocytes system.It ...By investigating a stochastic model for intracellular calcium oscillations proposed by Hfer,we have analyzed the transmission behavior of calcium signaling in a one-dimensional two-way coupled hepatocytes system.It is shown that when the first cell is subjected to the external noise,the output signal-to-noise ratio(SNR) in the cell exhibits two maxima as a function of external noise intensity,indicating the occurrence of stochastic bi-resonance(SBR).It is more important that when cells are coupled together,the resonant behavior in the 1st cell propagates along the chain with different features through the coupling effect.The cells whose locations are comparatively close to or far from the 1st cell can show SBR,while the cells located in the middle position can display stochastic multi-resonance(SMR).Fur-thermore,the number of cells that can show SMR increases with coupling strength enhancing.These results indicate that the cells system may make an effective choice in response to external signaling induced by noise,through the mechanism of SMR by adjusting coupling strength.展开更多
A series of quinoline derivatives was obtained in high yields by an efficient one-pot reaction of substituted o-diiodobenzenes with azazirconacyelopentadienes, which were conveniently prepared from one internal alkyne...A series of quinoline derivatives was obtained in high yields by an efficient one-pot reaction of substituted o-diiodobenzenes with azazirconacyelopentadienes, which were conveniently prepared from one internal alkyne and one nitrile mediated by zirconocene. This proposed synthetic method provides a feasible way to the synthesis of large N-heteroeyclic π-conjugated molecules.展开更多
Based on the formation of 2,5-bis（trimethylsilyl）-zirconacyclopentadienes from two silylalkynes with CpEZrBu2 and the Cu-mediated formation of 1,4-disilylbenzene via the cycloaddition of zirconacyclopentadienes to d...Based on the formation of 2,5-bis（trimethylsilyl）-zirconacyclopentadienes from two silylalkynes with CpEZrBu2 and the Cu-mediated formation of 1,4-disilylbenzene via the cycloaddition of zirconacyclopentadienes to disubstituted alkynes, a selective synthesis of 1,4-dialkyl（aryl）-hexa-substituted benzenes was achieved followed by iodination and coupling reaction. The coupling reactions were carried out with either organolithium reagent or orga- nozinc reagent（Negishi coupling）, depending on the electrophilic species.展开更多
基金supported by the National Natural Science Foundation for Theoretical Physics of China (11047017)the Wellcome Trust (081808/Z/06/Z)+1 种基金the Biotechnology and Biological Sciences Research Council (BBS/B1678X), UKthe Special Foundation of Education of Anhui Province for Excellent Young Scientists (2011SQRL023)
文摘Loss of function and gain of function mutations of the sodium channel were investigated using an intact two-dimensional rabbit sinoatrial node (SAN) and atrial cell model. The effects of three external stimuli (acetylcholine secretion by the vagal nerve, acid-base concentration, and tissue temperature) on cardiac pacemaker function and conduction were studied. Our results show that these two groups of mutations have different effects on pacemaker function and conduction. Furthermore, we found that the negative effects of these mutations could be altered by external stimuli. The bradycardic effects of mutations were magnified by an increase in acetylcholine level. Changes in acid-base concentration and tissue temperature increased the ability of the SAN to recover its pacemaker function. The results of this study increase our understanding of sodium channel disorders, and help to advance research on the treatment of these conditions.
基金the Research Fund of Anhui Normal University(Grant No.2006xzx09)the Educational Commission of Anhui Province of China(Grant No.KJ2007A079)the Program for Innovative Research Team in Anhui Normal University
文摘By investigating a stochastic model for intracellular calcium oscillations proposed by Hfer,we have analyzed the transmission behavior of calcium signaling in a one-dimensional two-way coupled hepatocytes system.It is shown that when the first cell is subjected to the external noise,the output signal-to-noise ratio(SNR) in the cell exhibits two maxima as a function of external noise intensity,indicating the occurrence of stochastic bi-resonance(SBR).It is more important that when cells are coupled together,the resonant behavior in the 1st cell propagates along the chain with different features through the coupling effect.The cells whose locations are comparatively close to or far from the 1st cell can show SBR,while the cells located in the middle position can display stochastic multi-resonance(SMR).Fur-thermore,the number of cells that can show SMR increases with coupling strength enhancing.These results indicate that the cells system may make an effective choice in response to external signaling induced by noise,through the mechanism of SMR by adjusting coupling strength.
基金Supported by the National Natural Science Foundation of China（No.21102099）.
文摘A series of quinoline derivatives was obtained in high yields by an efficient one-pot reaction of substituted o-diiodobenzenes with azazirconacyelopentadienes, which were conveniently prepared from one internal alkyne and one nitrile mediated by zirconocene. This proposed synthetic method provides a feasible way to the synthesis of large N-heteroeyclic π-conjugated molecules.
基金Supported by the National Natural Science Foundation of China（No.21102099）.
文摘Based on the formation of 2,5-bis（trimethylsilyl）-zirconacyclopentadienes from two silylalkynes with CpEZrBu2 and the Cu-mediated formation of 1,4-disilylbenzene via the cycloaddition of zirconacyclopentadienes to disubstituted alkynes, a selective synthesis of 1,4-dialkyl（aryl）-hexa-substituted benzenes was achieved followed by iodination and coupling reaction. The coupling reactions were carried out with either organolithium reagent or orga- nozinc reagent（Negishi coupling）, depending on the electrophilic species.
