Glucose transporter 4 (GLUT4) is responsible for insulin-stimulated glucose transporting into the insulin-sensitive fat and muscle cells. The dynamics of GLUT4 storage vesicles (GSVs) remains to be explored and it is ...Glucose transporter 4 (GLUT4) is responsible for insulin-stimulated glucose transporting into the insulin-sensitive fat and muscle cells. The dynamics of GLUT4 storage vesicles (GSVs) remains to be explored and it is unclear how GSVs are arranged based on their mobility. We examined this issue in 3T3-L1 cells via investigating the three-dimensional mobility of single GSV labeled with EGFP-fused GLUT4. A thin layer of cytosol right adjacent to the plasma membrane was illuminated and successively imaged at 5 Hz under a total internal reflection fluorescence microscope with a penetration depth of 136 nm. Employing single particle tracking, the three-dimensional subpixel displacement of single GSV was tracked at a spatial precision of 22 nm. Both the mean square displacement and the diffusion coefficient were calculated for each vesicle. Tracking results revealed that vesicles moved as if restricted within a cage that has a mean radius of 160 nm, suggesting the presence of some intracellular tethering matrix. By constructing the histogram of the diffusion coefficients of GSVs, we observed a smooth distribution instead of the existence of distinct groups. The result indicates that GSVs are dynamically retained in a continuous and wide range of mobility rather than into separate classes.展开更多
A singlemode-multimode-singlemode （SMS） fiber structure for temperature measurement using an optical time domain reflectometer （OTDR）-based interrogation system is proposed. A temperature measurement range of 40 ...A singlemode-multimode-singlemode （SMS） fiber structure for temperature measurement using an optical time domain reflectometer （OTDR）-based interrogation system is proposed. A temperature measurement range of 40 ℃-195 ℃ with a resolution of 0.12 ℃ and a linearity of 0.992 could be achieved for the multimode fiber （MMF） graded index with a length of 60mm. It was also demonstrated that two-point temperature measurement with two SMS fiber structures as temperature sensors could be made. The proposed temperature measurement system offered a high resolution and also benefited from a simple configuration with a capability of multi-point temperature measurement.展开更多
文摘Glucose transporter 4 (GLUT4) is responsible for insulin-stimulated glucose transporting into the insulin-sensitive fat and muscle cells. The dynamics of GLUT4 storage vesicles (GSVs) remains to be explored and it is unclear how GSVs are arranged based on their mobility. We examined this issue in 3T3-L1 cells via investigating the three-dimensional mobility of single GSV labeled with EGFP-fused GLUT4. A thin layer of cytosol right adjacent to the plasma membrane was illuminated and successively imaged at 5 Hz under a total internal reflection fluorescence microscope with a penetration depth of 136 nm. Employing single particle tracking, the three-dimensional subpixel displacement of single GSV was tracked at a spatial precision of 22 nm. Both the mean square displacement and the diffusion coefficient were calculated for each vesicle. Tracking results revealed that vesicles moved as if restricted within a cage that has a mean radius of 160 nm, suggesting the presence of some intracellular tethering matrix. By constructing the histogram of the diffusion coefficients of GSVs, we observed a smooth distribution instead of the existence of distinct groups. The result indicates that GSVs are dynamically retained in a continuous and wide range of mobility rather than into separate classes.
基金This work was supported Technology Research Grant Science Foundation. by Science and Indonesia Toray
文摘A singlemode-multimode-singlemode （SMS） fiber structure for temperature measurement using an optical time domain reflectometer （OTDR）-based interrogation system is proposed. A temperature measurement range of 40 ℃-195 ℃ with a resolution of 0.12 ℃ and a linearity of 0.992 could be achieved for the multimode fiber （MMF） graded index with a length of 60mm. It was also demonstrated that two-point temperature measurement with two SMS fiber structures as temperature sensors could be made. The proposed temperature measurement system offered a high resolution and also benefited from a simple configuration with a capability of multi-point temperature measurement.
