The rate constants of transmembrane transport of Ni 2+ and Cd 2+ with the same charge and different configurations of electron were determined in this experiment, and their first-order kinetic rate constant is as foll...The rate constants of transmembrane transport of Ni 2+ and Cd 2+ with the same charge and different configurations of electron were determined in this experiment, and their first-order kinetic rate constant is as follows: for Ni 2+, k(Ni 2+)=0.002 0 h -1, and for Cd 2+, k(Cd 2+)=0.021 h -1. There are large differences between their rates of transmemebrane transport. The mechanisms of transmembrane transport of Ni 2+ and Cd 2+ are studied at the same time. The influences of the concentration of metal ions, pH of solution and the transport inhibitor on the uptake of Ni 2+ and Cd 2+ by human erythrocytes have been studied. The results show that Ni 2+ ions pass through the membrane by passive diffusion, while for Cd 2+, some of them are transported by the anion channel, the others by passive diffusion. Because there are different configurations of electron in the two ions, there are large difference in action of them with protein in the membrane of human erythrocytes.展开更多
The erythrocyte hemolysis was examined to assure Rb^＋ to have a weak toxicity toward human body. The way of Rb^＋ transporting into human erythrocytes was determined, and the factors to affect this transport process ...The erythrocyte hemolysis was examined to assure Rb^＋ to have a weak toxicity toward human body. The way of Rb^＋ transporting into human erythrocytes was determined, and the factors to affect this transport process were evaluated. The effects of extracellular concentration of Rb^＋, incubation temperature, incubation time, medium pH, and specific inhibitors were investigated via flame atomic absorption spectrometry. The results indicated that the membrane transport of Rb^＋ through human erythrocytes was controlled mainly by both active transport and simple diffusion. Every mentioned factor took a positive effect on the Rb^＋ uptake by human erythrocytes, however neither DIDS nor nefidpine could inhibit the uptake of Rb^＋.展开更多
The ability to discriminate between single cells in a label-free and noninvasive fashion is important for the classification of cells, and for the identification of similar cells from different origins. In this paper,...The ability to discriminate between single cells in a label-free and noninvasive fashion is important for the classification of cells, and for the identification of similar cells from different origins. In this paper, we present the Raman spectroscopy-based identifi- cation of different types of single cells in aqueous media, and discrimination between the same types of cells from different donors using a novel Laser Tweezers Raman Spectroscopy (LTRS) technique, which combines laser trapping and micro-Raman spectroscopy. First, we measured the spectra of individual living human erythrocytes, i.e. red blood cells, and leucocytes (U937 cancer cells). High-quality Raman spectra with low fluorescence were obtained using a home-LTRS apparatus and 20 cells were measured for each cell type. The smoothing, baseline subtraction, and normalization of the data were followed by a principal components analysis (PCA). The PCA loading plots showed that the two different types of cells could be completely separated based only on the first component (PC1) (i.e. the peaks at 1300 cm1 ); the discrimination accuracy could therefore reach 100%. More than 50 spectra were taken for each erythrocyte obtained from the four healthy volunteers. The average discrimination accuracy was 84.5% for two random individuals taken from the four volunteers, according to the first and second PCs. This work demonstrates that LTRS is a powerful tool for the accurate identification and discrimination of single cells, and it has the potential to be applied for the highly sensitive identification of cells in clinical diagnosis and medical jurisprudence.展开更多
The cytosolic free Ca<sup>2+</sup> in erythrocytes is around 10<sup>-6</sup> mol/L, whereas the extracellularCa<sup>2+</sup> concentration is about 10<sup>-3</sup> mol/L...The cytosolic free Ca<sup>2+</sup> in erythrocytes is around 10<sup>-6</sup> mol/L, whereas the extracellularCa<sup>2+</sup> concentration is about 10<sup>-3</sup> mol/L. Thus it results in 1000-fold transmembraneCa<sup>2+</sup> gradient across erythrocyte membrane. Our previous results have shown展开更多
文摘The rate constants of transmembrane transport of Ni 2+ and Cd 2+ with the same charge and different configurations of electron were determined in this experiment, and their first-order kinetic rate constant is as follows: for Ni 2+, k(Ni 2+)=0.002 0 h -1, and for Cd 2+, k(Cd 2+)=0.021 h -1. There are large differences between their rates of transmemebrane transport. The mechanisms of transmembrane transport of Ni 2+ and Cd 2+ are studied at the same time. The influences of the concentration of metal ions, pH of solution and the transport inhibitor on the uptake of Ni 2+ and Cd 2+ by human erythrocytes have been studied. The results show that Ni 2+ ions pass through the membrane by passive diffusion, while for Cd 2+, some of them are transported by the anion channel, the others by passive diffusion. Because there are different configurations of electron in the two ions, there are large difference in action of them with protein in the membrane of human erythrocytes.
基金Project supported by the National Natural Science Foundation of China （No. 20471035） and the Natural Science Foundation of Shaanxi Province （No. 20041317）.
文摘The erythrocyte hemolysis was examined to assure Rb^＋ to have a weak toxicity toward human body. The way of Rb^＋ transporting into human erythrocytes was determined, and the factors to affect this transport process were evaluated. The effects of extracellular concentration of Rb^＋, incubation temperature, incubation time, medium pH, and specific inhibitors were investigated via flame atomic absorption spectrometry. The results indicated that the membrane transport of Rb^＋ through human erythrocytes was controlled mainly by both active transport and simple diffusion. Every mentioned factor took a positive effect on the Rb^＋ uptake by human erythrocytes, however neither DIDS nor nefidpine could inhibit the uptake of Rb^＋.
基金supported by Beijing Natural Science Foundation(5102019)National Science and Technology Infrastructure Program(2012BAF14B14)
文摘The ability to discriminate between single cells in a label-free and noninvasive fashion is important for the classification of cells, and for the identification of similar cells from different origins. In this paper, we present the Raman spectroscopy-based identifi- cation of different types of single cells in aqueous media, and discrimination between the same types of cells from different donors using a novel Laser Tweezers Raman Spectroscopy (LTRS) technique, which combines laser trapping and micro-Raman spectroscopy. First, we measured the spectra of individual living human erythrocytes, i.e. red blood cells, and leucocytes (U937 cancer cells). High-quality Raman spectra with low fluorescence were obtained using a home-LTRS apparatus and 20 cells were measured for each cell type. The smoothing, baseline subtraction, and normalization of the data were followed by a principal components analysis (PCA). The PCA loading plots showed that the two different types of cells could be completely separated based only on the first component (PC1) (i.e. the peaks at 1300 cm1 ); the discrimination accuracy could therefore reach 100%. More than 50 spectra were taken for each erythrocyte obtained from the four healthy volunteers. The average discrimination accuracy was 84.5% for two random individuals taken from the four volunteers, according to the first and second PCs. This work demonstrates that LTRS is a powerful tool for the accurate identification and discrimination of single cells, and it has the potential to be applied for the highly sensitive identification of cells in clinical diagnosis and medical jurisprudence.
文摘The cytosolic free Ca<sup>2+</sup> in erythrocytes is around 10<sup>-6</sup> mol/L, whereas the extracellularCa<sup>2+</sup> concentration is about 10<sup>-3</sup> mol/L. Thus it results in 1000-fold transmembraneCa<sup>2+</sup> gradient across erythrocyte membrane. Our previous results have shown
