In this work, the interaction between chelerythrine （CHE） and guanosine is studied using UV-vis and fluorescence measurements at various temperatures. The UV-vis spectra show that the increasing guanosine concentrat...In this work, the interaction between chelerythrine （CHE） and guanosine is studied using UV-vis and fluorescence measurements at various temperatures. The UV-vis spectra show that the increasing guanosine concentrations result in the decreasing absorption intensity and red shift of CHE E absorption band （267 nm）. The fluorescence spectra are fitted to linear analysis, yielding a binding constant of 1.04×10^4 L/tool at 298.15 K of CHE with guanosine. Besides, with △rHm^θ = - 8.26 kJ/mol, △rGm^θ = -22.90 kJ/mol, and △rSm^θ = 49.38 J/（mol K） the interaction should be entropy-driven and exterothermic.展开更多
To study the possible anticancer mechanisms of chelerythrine (CHE), and its interactions with cytidine were investigated by UV–vis spectrophotometric and spectrofluorimetric measurements and by thermodynamic calculat...To study the possible anticancer mechanisms of chelerythrine (CHE), and its interactions with cytidine were investigated by UV–vis spectrophotometric and spectrofluorimetric measurements and by thermodynamic calculations. The binding of CHE to cytidine could be characterized by the hypochromic and bathochromic effects in the absorption bands, and the quenching of fluorescence intensity. The spectral data were fit by linear analysis, yielding a binding constant of 2.49 × 10(4) L mol(?1)at 25 °C of CHE and cytidine, and a van’t Hoff enthalpy of ?20.02 kJ/mol for the exothermic interaction in the standard state. In addition, with and , the interactions should be entropy-driven.展开更多
The interaction between sanguinarine and guanosine was investigated by using UV-vis and fluorescence spectra at pH 7.2. The binding of sanguinarine to guanosine was substantiated by the hypochromism and bathochromism ...The interaction between sanguinarine and guanosine was investigated by using UV-vis and fluorescence spectra at pH 7.2. The binding of sanguinarine to guanosine was substantiated by the hypochromism and bathochromism in the absorption spectra and the emission quenching in fluorescence spectra. The fluorescence lifetime results, the varieties of the fluorophore absorption spectra and the decrease of the binding constant with the increasing temperature all indicate that the fluorescence quenching is static. The ratio and constant of the binding cytidine to sanguinarine are 2 and 6.44 × 10^7, respectively. The result shows that the binding of sanguinarine to guanosine is not only exothermic but also entropy-driven with △H=-8.53kJ/mol, AS = 0.12 kJ/（molK）, and AG =-44.57 kJ/mol at 298.15 K.展开更多
The induction of MT（metallothionein） by Cd（Ⅱ） and Zn（Ⅱ） in renal proximal tubule cells （LLC-PKI） and the effects of simultaneous administration of Cd（Ⅱ） and Zn（Ⅱ） on MT induction were discussed. The tw...The induction of MT（metallothionein） by Cd（Ⅱ） and Zn（Ⅱ） in renal proximal tubule cells （LLC-PKI） and the effects of simultaneous administration of Cd（Ⅱ） and Zn（Ⅱ） on MT induction were discussed. The two metals administered together are able to induce MT to almost 40/ag MT/mg protein. The additive production of MT may be due to two different effects by Cd（Ⅱ） and Zn（Ⅱ） on the activation of MT transcription. The experiments of simultaneous administration of Cd（Ⅱ） and Zn（Ⅱ） to the renal proximal tubule cells demonstrated the interaction of these metals, MT induction and proximal tubule toxicity.展开更多
In this paper, we introduce the notion of the strongly simple cycles with some rotation pair for interval maps and prove that, if an interval map has a cycle with given rotation pair, then it, has a strongly simple cy...In this paper, we introduce the notion of the strongly simple cycles with some rotation pair for interval maps and prove that, if an interval map has a cycle with given rotation pair, then it, has a strongly simple cycle with the same rotation pair.展开更多
基金This project is financed by Jiangxi Boyuan Industry Co.,Ltd.(Jiangxi province,China)
文摘In this work, the interaction between chelerythrine （CHE） and guanosine is studied using UV-vis and fluorescence measurements at various temperatures. The UV-vis spectra show that the increasing guanosine concentrations result in the decreasing absorption intensity and red shift of CHE E absorption band （267 nm）. The fluorescence spectra are fitted to linear analysis, yielding a binding constant of 1.04×10^4 L/tool at 298.15 K of CHE with guanosine. Besides, with △rHm^θ = - 8.26 kJ/mol, △rGm^θ = -22.90 kJ/mol, and △rSm^θ = 49.38 J/（mol K） the interaction should be entropy-driven and exterothermic.
文摘To study the possible anticancer mechanisms of chelerythrine (CHE), and its interactions with cytidine were investigated by UV–vis spectrophotometric and spectrofluorimetric measurements and by thermodynamic calculations. The binding of CHE to cytidine could be characterized by the hypochromic and bathochromic effects in the absorption bands, and the quenching of fluorescence intensity. The spectral data were fit by linear analysis, yielding a binding constant of 2.49 × 10(4) L mol(?1)at 25 °C of CHE and cytidine, and a van’t Hoff enthalpy of ?20.02 kJ/mol for the exothermic interaction in the standard state. In addition, with and , the interactions should be entropy-driven.
文摘The interaction between sanguinarine and guanosine was investigated by using UV-vis and fluorescence spectra at pH 7.2. The binding of sanguinarine to guanosine was substantiated by the hypochromism and bathochromism in the absorption spectra and the emission quenching in fluorescence spectra. The fluorescence lifetime results, the varieties of the fluorophore absorption spectra and the decrease of the binding constant with the increasing temperature all indicate that the fluorescence quenching is static. The ratio and constant of the binding cytidine to sanguinarine are 2 and 6.44 × 10^7, respectively. The result shows that the binding of sanguinarine to guanosine is not only exothermic but also entropy-driven with △H=-8.53kJ/mol, AS = 0.12 kJ/（molK）, and AG =-44.57 kJ/mol at 298.15 K.
文摘The induction of MT（metallothionein） by Cd（Ⅱ） and Zn（Ⅱ） in renal proximal tubule cells （LLC-PKI） and the effects of simultaneous administration of Cd（Ⅱ） and Zn（Ⅱ） on MT induction were discussed. The two metals administered together are able to induce MT to almost 40/ag MT/mg protein. The additive production of MT may be due to two different effects by Cd（Ⅱ） and Zn（Ⅱ） on the activation of MT transcription. The experiments of simultaneous administration of Cd（Ⅱ） and Zn（Ⅱ） to the renal proximal tubule cells demonstrated the interaction of these metals, MT induction and proximal tubule toxicity.
文摘In this paper, we introduce the notion of the strongly simple cycles with some rotation pair for interval maps and prove that, if an interval map has a cycle with given rotation pair, then it, has a strongly simple cycle with the same rotation pair.
