Differential scanning calorimetry (DSC), fluorescence polarization and X-ray diffraction were per-formed to investigate the kinetics of the micellar to the lamellar phase transition of dipalmitoylphosphatidylcholine/1...Differential scanning calorimetry (DSC), fluorescence polarization and X-ray diffraction were per-formed to investigate the kinetics of the micellar to the lamellar phase transition of dipalmitoylphosphatidylcholine/1-palmitoylphosphatidylcholine (16:0 LPC/DPPC) liposomes at gel phase. With a 16:0 LPC concentration up to 27 mol% only the sharp main transition with relatively high enthalpy (△H) values of DPPC was observed. Increasing 16 : 0 LPC concentration, the phase transition was broadened and the transition enthalpy was decreased and finally totally disappeared. The fluorescence probes of 3AS, 9AS, 12AS, and 16AP were employed, respectively, to detect the mo-bility of various sites of carbon chains of DPPC or 16:0 LPC/DPPC liposomes. It was shown that DPPC liposomes formed in the absence of 16:0 LPC always had a fluidity gradient in both gel and liquid-crystalline phase, while in the presence of 14.1 mol% and 27.0 mol% 16:0 LPC in the mixtures, the fluidity gradient tended to disappear below 40℃:展开更多
The studies of the effects of lanthanides on biological system show that lanthanides(Ln<sup>3+</sup>)can facilitate growth of crops and increase their products.However,Ln<sup>3+</sup> is toxict...The studies of the effects of lanthanides on biological system show that lanthanides(Ln<sup>3+</sup>)can facilitate growth of crops and increase their products.However,Ln<sup>3+</sup> is toxicto some animal tissues,although the reaction mechanism of Ln<sup>3+</sup> in biological system isnot clear.Some roles of Ln<sup>3+</sup> in living system may be related to the competition withCa<sup>2+</sup>.Calmodulin（CaM）,an ubiquitous Ca<sup>2+</sup>-binding protein that mediates展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘Differential scanning calorimetry (DSC), fluorescence polarization and X-ray diffraction were per-formed to investigate the kinetics of the micellar to the lamellar phase transition of dipalmitoylphosphatidylcholine/1-palmitoylphosphatidylcholine (16:0 LPC/DPPC) liposomes at gel phase. With a 16:0 LPC concentration up to 27 mol% only the sharp main transition with relatively high enthalpy (△H) values of DPPC was observed. Increasing 16 : 0 LPC concentration, the phase transition was broadened and the transition enthalpy was decreased and finally totally disappeared. The fluorescence probes of 3AS, 9AS, 12AS, and 16AP were employed, respectively, to detect the mo-bility of various sites of carbon chains of DPPC or 16:0 LPC/DPPC liposomes. It was shown that DPPC liposomes formed in the absence of 16:0 LPC always had a fluidity gradient in both gel and liquid-crystalline phase, while in the presence of 14.1 mol% and 27.0 mol% 16:0 LPC in the mixtures, the fluidity gradient tended to disappear below 40℃:
基金supported by the National Naural Sdence FoUndation of China
文摘The studies of the effects of lanthanides on biological system show that lanthanides(Ln<sup>3+</sup>)can facilitate growth of crops and increase their products.However,Ln<sup>3+</sup> is toxicto some animal tissues,although the reaction mechanism of Ln<sup>3+</sup> in biological system isnot clear.Some roles of Ln<sup>3+</sup> in living system may be related to the competition withCa<sup>2+</sup>.Calmodulin（CaM）,an ubiquitous Ca<sup>2+</sup>-binding protein that mediates
