Traditionally, the multibasic cleavage site （MBCS） of surface protein H5-hemagglutinin （HA） is converted to a monobasic one so as to weaken the virulence of recombinant H5N1 influenza viruses and to produce inacti...Traditionally, the multibasic cleavage site （MBCS） of surface protein H5-hemagglutinin （HA） is converted to a monobasic one so as to weaken the virulence of recombinant H5N1 influenza viruses and to produce inactivated and live attenuated vaccines. Whether such modification benefits new candidate vaccines has not been adequately investigated. We previously used retroviral vectors to generate wtH5N1 pseudotypes containing the wild-type HA （wtH5） from A/swine/Anhui/ca/2004 （H5N1） virus. Here, we generated mtH5N1 pseudotypes, which contained a mutant-type HA （mtH5） with a modified monobasic cleavage site. Groups of mice were subcutaneously injected with the two types of influenza pseudotypes. Compared to the group immunized with wtH5N1 pseudotypes, the inoculation of mtH5N1 pseudotypes induced significantly higher levels of HA specific IgG and IFN-y in immunized mice, and enhanced protection against the challenge of mouse-adapted avian influenza virus A/Chicken/Henardl2/2004 （H5N1）. This study suggests modification of the H5-hemagglutinin MBCS in retroviral pseudotypes enhances protection efficacy in mice and this information may be helpful for development of vaccines from mammalian cells to fight against H5N 1 influenza viruses.展开更多
In wireless sensor networks,node localization is a fundamental middleware service.In this paper,a robust and accurate localization algorithm is proposed,which uses a novel iterative clustering model to obtain the most...In wireless sensor networks,node localization is a fundamental middleware service.In this paper,a robust and accurate localization algorithm is proposed,which uses a novel iterative clustering model to obtain the most representative intersection points between every two circles and use them to estimate the position of unknown nodes.Simulation results demonstrate that the proposed algorithm outperforms other localization schemes (such as Min-Max,etc.) in accuracy,scalability and gross error tolerance.展开更多
基金supported by the National Basic Research Program of China (973: 2012CB518904) from the Ministry of Science and Technology of Chinathe National Natural Science Foundation of China(81201298)
文摘Traditionally, the multibasic cleavage site （MBCS） of surface protein H5-hemagglutinin （HA） is converted to a monobasic one so as to weaken the virulence of recombinant H5N1 influenza viruses and to produce inactivated and live attenuated vaccines. Whether such modification benefits new candidate vaccines has not been adequately investigated. We previously used retroviral vectors to generate wtH5N1 pseudotypes containing the wild-type HA （wtH5） from A/swine/Anhui/ca/2004 （H5N1） virus. Here, we generated mtH5N1 pseudotypes, which contained a mutant-type HA （mtH5） with a modified monobasic cleavage site. Groups of mice were subcutaneously injected with the two types of influenza pseudotypes. Compared to the group immunized with wtH5N1 pseudotypes, the inoculation of mtH5N1 pseudotypes induced significantly higher levels of HA specific IgG and IFN-y in immunized mice, and enhanced protection against the challenge of mouse-adapted avian influenza virus A/Chicken/Henardl2/2004 （H5N1）. This study suggests modification of the H5-hemagglutinin MBCS in retroviral pseudotypes enhances protection efficacy in mice and this information may be helpful for development of vaccines from mammalian cells to fight against H5N 1 influenza viruses.
基金supported in part by the Key Program of National Natural Science Foundation of China(Grant No.60873244,60973110,61003307)the Beijing Municipal Natural Science Foundation(Grant No.4102059)
文摘In wireless sensor networks,node localization is a fundamental middleware service.In this paper,a robust and accurate localization algorithm is proposed,which uses a novel iterative clustering model to obtain the most representative intersection points between every two circles and use them to estimate the position of unknown nodes.Simulation results demonstrate that the proposed algorithm outperforms other localization schemes (such as Min-Max,etc.) in accuracy,scalability and gross error tolerance.
