Objective To evaluate senile plaque formation and compare the sensitivity of three differentβ-amyloid(Aβ)labeling methods(antibody staining,Gallyas silver staining,and thioflavin-S staining)to detect Aβdeposition.M...Objective To evaluate senile plaque formation and compare the sensitivity of three differentβ-amyloid(Aβ)labeling methods(antibody staining,Gallyas silver staining,and thioflavin-S staining)to detect Aβdeposition.Methods APPswe/PSEN1dE9 transgenic mice(APP/PS1)of different ages were used to examine spatiotemporal changes in Aβplaque deposition.Antibody staining,Gallyas silver staining,and thioflavin-S staining were used to detect Aβplaque deposition in the same brain region of adjacent slices from model mice,and the results were compared.Results With aging,Aβplaques first appeared in the cortex and then the deposition increased throughout the whole brain.Significantly greater plaque deposition was detected by 6E10 antibody than that analyzed with Gallyas silver staining or thioflavin-S staining(P<0.05).Plaque deposition did not show significant difference between the APP/PS1 mice brains assayed with Gallyas silver staining and ones with thioflavin-S staining(P=0.0033).Conclusions The APP/PS1 mouse model of Alzheimer’s disease could mimick the progress of Aβplaques occurred in patients with Alzheimer’s disease.Antibody detection of Aβdeposition may be more sensitive than chemical staining methods.展开更多
G-quadruplex ligands have been accepted as potential therapeutic agents for anticancer treatment. Thioflavin T （ThT）, a highly selective G-quadruplex ligand, can bind G-quadruplex with a fluorescent light-up signal ...G-quadruplex ligands have been accepted as potential therapeutic agents for anticancer treatment. Thioflavin T （ThT）, a highly selective G-quadruplex ligand, can bind G-quadruplex with a fluorescent light-up signal change and high specificity against DNA duplex. However, there are still different opinions that ThT induces/stabilizes G-quadruplex foldings/topologies in human telomere sequence. Here, a sensitive single-molecule nanopore technology was utilized to analyze the interactions between human telomeric DNA （Tel DNA） and ThT. Both translocation time and current blockade were measured to investigate the translocation behaviors. Furthermore, the effects of metal ion （K~ and Na~） and pH on the translocation behaviors were studied. Based on the single-molecule level analysis, there are some conclusions： （1） In the electrolyte solution containing 50 mmol/L I（Cl and 450 mmol/L NaCl, ThT can bind strongly with Tel DNA but nearly does not change the G-quadruplex form; （2） in the presence of high concentration K~, the ThT binding induces the structural change of hybrid G-quadruplex into antiparallel topology with an enhanced structural stability; （3） In either alkaline or acidic buffer, G-quadruplex form will change in certain degree. All above conclusions are helpful to deeply understand the interaction behaviors between Tel DNA and ThT. This nanopore platform, investigating G-quadruplex ligands at the single-molecule level, has great potential for the design of new drugs and sensors.展开更多
本研究旨在探究不同金属离子(NaCl、KCl、CaCl_(2)、AlCl_(3)和FeCl_(3))对乳清分离蛋白(whey protein isolate,WPI)纤维聚合物聚合动力学、形态和结构的影响。结果表明,不同金属离子影响了WPI纤维聚合物的最终结构和特征。NaCl、KCl和C...本研究旨在探究不同金属离子(NaCl、KCl、CaCl_(2)、AlCl_(3)和FeCl_(3))对乳清分离蛋白(whey protein isolate,WPI)纤维聚合物聚合动力学、形态和结构的影响。结果表明,不同金属离子影响了WPI纤维聚合物的最终结构和特征。NaCl、KCl和CaCl_(2)对WPI的聚集影响较小,增加了溶液pH和电导率,而AlCl_(3)和FeCl_(3)加速了WPI的聚集,降低了溶液pH,增加了溶液电导率;与原始WPI纤维聚合物硫黄素T(Th T)荧光强度(388.92)相比,NaCl、KCl和CaCl_(2)增加Th T荧光强度分别至465.39、433.37和486.83,增加了WPI纤维聚合物的生成量,AlCl_(3)和FeCl_(3)降低Th T荧光强度分别至228.81和90.24,降低了WPI纤维聚合物的生成量;不同金属离子均改变了WPI聚合动力学,降低了(df/dt)_(max)值,并改变了滞后时间;NaCl、KCl和CaCl_(2)对WPI纤维聚合物的形态影响较小,AlCl_(3)和FeCl_(3)使WPI纤维聚合物更团簇、粗而杂乱;傅里叶红外光谱结果表明,NaCl、KCl和CaCl_(2)促进β-折叠结构生成,而AlCl_(3)和FeCl_(3)抑制了β-折叠生成,不同金属离子的加入均改变了纤维中β-链间的特征距离。这些结果为利用WPI制备不同聚集形态的纤维聚合物提供了科学依据。展开更多
基金Supported by the 2016 Major Collaborative Innovation Program of the Chinese Academy of Medical Sciences(2016-I2M-1004)
文摘Objective To evaluate senile plaque formation and compare the sensitivity of three differentβ-amyloid(Aβ)labeling methods(antibody staining,Gallyas silver staining,and thioflavin-S staining)to detect Aβdeposition.Methods APPswe/PSEN1dE9 transgenic mice(APP/PS1)of different ages were used to examine spatiotemporal changes in Aβplaque deposition.Antibody staining,Gallyas silver staining,and thioflavin-S staining were used to detect Aβplaque deposition in the same brain region of adjacent slices from model mice,and the results were compared.Results With aging,Aβplaques first appeared in the cortex and then the deposition increased throughout the whole brain.Significantly greater plaque deposition was detected by 6E10 antibody than that analyzed with Gallyas silver staining or thioflavin-S staining(P<0.05).Plaque deposition did not show significant difference between the APP/PS1 mice brains assayed with Gallyas silver staining and ones with thioflavin-S staining(P=0.0033).Conclusions The APP/PS1 mouse model of Alzheimer’s disease could mimick the progress of Aβplaques occurred in patients with Alzheimer’s disease.Antibody detection of Aβdeposition may be more sensitive than chemical staining methods.
基金financially supported by the National Natural Science Foundation of China(No. 21475091)the Science andTechnology Department of Sichuan Province(No. 2015GZ0301)
文摘G-quadruplex ligands have been accepted as potential therapeutic agents for anticancer treatment. Thioflavin T （ThT）, a highly selective G-quadruplex ligand, can bind G-quadruplex with a fluorescent light-up signal change and high specificity against DNA duplex. However, there are still different opinions that ThT induces/stabilizes G-quadruplex foldings/topologies in human telomere sequence. Here, a sensitive single-molecule nanopore technology was utilized to analyze the interactions between human telomeric DNA （Tel DNA） and ThT. Both translocation time and current blockade were measured to investigate the translocation behaviors. Furthermore, the effects of metal ion （K~ and Na~） and pH on the translocation behaviors were studied. Based on the single-molecule level analysis, there are some conclusions： （1） In the electrolyte solution containing 50 mmol/L I（Cl and 450 mmol/L NaCl, ThT can bind strongly with Tel DNA but nearly does not change the G-quadruplex form; （2） in the presence of high concentration K~, the ThT binding induces the structural change of hybrid G-quadruplex into antiparallel topology with an enhanced structural stability; （3） In either alkaline or acidic buffer, G-quadruplex form will change in certain degree. All above conclusions are helpful to deeply understand the interaction behaviors between Tel DNA and ThT. This nanopore platform, investigating G-quadruplex ligands at the single-molecule level, has great potential for the design of new drugs and sensors.
