Objective To explore the role of HIV-1 tat gene variations in AIDS dementia complex （ADC） pathogenesis. Methods HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC an...Objective To explore the role of HIV-1 tat gene variations in AIDS dementia complex （ADC） pathogenesis. Methods HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC and an AIDS patient without ADC were cloned for sequence analysis. HIV-1 tat gene sequence alignment was performed by using CLUSTAL W and the phylogentic analysis was conducted by using Neighbor-joining with MEGA4 software. All tat genes were used to construct recombinant retroviral expressing vector MSCV-IRES-GFP/tat. The MSCV-IRES-GFP/tat was cotransfected into 293T cells with pCMV-VSV-G and pUMVC vectors to assemble the recombinant retrovirus. After infection of gliomas U87 cells with equal amount of the recombinant retrovirus, TNF-α, and IL-1β concentrations in the supernatant of U87 cells were determined with ELISA. Results HIV-1 tat genes derived from peripheral spleen and central basal ganglia of the AIDS patient with ADC and the other one without ADC exhibited genetic variations. Tat variations and amino acid mutation sites existed mainly at Tat protein core functional area （38-47aa）. All Tat proteins could induce ug7 cells to produce TNF-α and IL-1β, but the level of IL-1β production was different among Tat proteins derived from the ADC patient＇s spleen, basal ganglia, and the non-ADC patient＇s spleen. The level of Tat proteins derived from the ADC patient＇s spleen, basal ganglia, and the non-ADC patient＇s spleen were obviously higher than that from the non-ADC patient＇s basal ganglia. Conclusion Tat protein core functional area （38-47aa） may serve as the key area of enhancing the secretion of IL-1β. This may be related with the neurotoxicity of HIV-1 Tat.展开更多
This paper presents a new method for computation of the monostatic radar cross section (RCS) of electrically large conducting objects. Compared with the traditional Z-buffer technique, the improved one can record not ...This paper presents a new method for computation of the monostatic radar cross section (RCS) of electrically large conducting objects. Compared with the traditional Z-buffer technique, the improved one can record not only the illuminated surface of the body, but also the information about the shadowed part. So multi-scattering and RCS of cavity can be calculated. The second advantage of it is using dual representation, of the target's facet surface, in which the illuminated part is treated as bicubic patches for RCS calculation, and is simplified to flat facet when ray tracing is done. Excellent agreement with the experiment has been obtained.展开更多
基金supported by the Science&Technology Development Program of Shandong Province(Grant No.2007GG30002003)
文摘Objective To explore the role of HIV-1 tat gene variations in AIDS dementia complex （ADC） pathogenesis. Methods HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC and an AIDS patient without ADC were cloned for sequence analysis. HIV-1 tat gene sequence alignment was performed by using CLUSTAL W and the phylogentic analysis was conducted by using Neighbor-joining with MEGA4 software. All tat genes were used to construct recombinant retroviral expressing vector MSCV-IRES-GFP/tat. The MSCV-IRES-GFP/tat was cotransfected into 293T cells with pCMV-VSV-G and pUMVC vectors to assemble the recombinant retrovirus. After infection of gliomas U87 cells with equal amount of the recombinant retrovirus, TNF-α, and IL-1β concentrations in the supernatant of U87 cells were determined with ELISA. Results HIV-1 tat genes derived from peripheral spleen and central basal ganglia of the AIDS patient with ADC and the other one without ADC exhibited genetic variations. Tat variations and amino acid mutation sites existed mainly at Tat protein core functional area （38-47aa）. All Tat proteins could induce ug7 cells to produce TNF-α and IL-1β, but the level of IL-1β production was different among Tat proteins derived from the ADC patient＇s spleen, basal ganglia, and the non-ADC patient＇s spleen. The level of Tat proteins derived from the ADC patient＇s spleen, basal ganglia, and the non-ADC patient＇s spleen were obviously higher than that from the non-ADC patient＇s basal ganglia. Conclusion Tat protein core functional area （38-47aa） may serve as the key area of enhancing the secretion of IL-1β. This may be related with the neurotoxicity of HIV-1 Tat.
文摘This paper presents a new method for computation of the monostatic radar cross section (RCS) of electrically large conducting objects. Compared with the traditional Z-buffer technique, the improved one can record not only the illuminated surface of the body, but also the information about the shadowed part. So multi-scattering and RCS of cavity can be calculated. The second advantage of it is using dual representation, of the target's facet surface, in which the illuminated part is treated as bicubic patches for RCS calculation, and is simplified to flat facet when ray tracing is done. Excellent agreement with the experiment has been obtained.
