LFA-1 and Mac-l, two $2 integrin members constitutively expressed on neutrophils, mediate leukocyte recruitment cascade by binding to the same ligand of ICAM-1. The slow rolling and firm adhesion of leukocytes rely on...LFA-1 and Mac-l, two $2 integrin members constitutively expressed on neutrophils, mediate leukocyte recruitment cascade by binding to the same ligand of ICAM-1. The slow rolling and firm adhesion of leukocytes rely on LFA-1 while the cell crawling is dependent on Mac-1. We hypothesized that their distinct roles are likely attributed to the differences in the binding kinetics or in the diverse responses of outside-in and inside-out signaling. In this study, we compared the ICAM-1 binding features between soluble or membrane-expressed LFA-1 and Mac-1 with different affinity conformation using optical trap technique. Our data indicated that the affinity up-regulation from wide type （WT） to high affinity （HA） is off-rate dependent for LFA-1 but on-rate dependent for Mac-1. The structural bases of this new finding were found to be consistent with our previous simulations. These results furthered our understanding in their function differences under shear flow.展开更多
An IEEE-802.1 l ac-l＊ 1 wireless LAN system-on-a-chip （SoC） that integrates an analog front end, a digital base-band processor and a media access controller has been implemented in 65 nm CMOS technology. It can pro...An IEEE-802.1 l ac-l＊ 1 wireless LAN system-on-a-chip （SoC） that integrates an analog front end, a digital base-band processor and a media access controller has been implemented in 65 nm CMOS technology. It can provide significantly increased throughput, high efficiency rate selection, and fully backward compatibility with the existing 802.11 a/n WLAN protocols. Especially the measured maximum throughput of UDP traffic can be up to 267 Mbps.展开更多
文摘LFA-1 and Mac-l, two $2 integrin members constitutively expressed on neutrophils, mediate leukocyte recruitment cascade by binding to the same ligand of ICAM-1. The slow rolling and firm adhesion of leukocytes rely on LFA-1 while the cell crawling is dependent on Mac-1. We hypothesized that their distinct roles are likely attributed to the differences in the binding kinetics or in the diverse responses of outside-in and inside-out signaling. In this study, we compared the ICAM-1 binding features between soluble or membrane-expressed LFA-1 and Mac-1 with different affinity conformation using optical trap technique. Our data indicated that the affinity up-regulation from wide type （WT） to high affinity （HA） is off-rate dependent for LFA-1 but on-rate dependent for Mac-1. The structural bases of this new finding were found to be consistent with our previous simulations. These results furthered our understanding in their function differences under shear flow.
基金supported by the National Great Specific Project of China(No.2012ZX03004004_001)
文摘An IEEE-802.1 l ac-l＊ 1 wireless LAN system-on-a-chip （SoC） that integrates an analog front end, a digital base-band processor and a media access controller has been implemented in 65 nm CMOS technology. It can provide significantly increased throughput, high efficiency rate selection, and fully backward compatibility with the existing 802.11 a/n WLAN protocols. Especially the measured maximum throughput of UDP traffic can be up to 267 Mbps.
