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
In order to verify the feasibility and stability of a degree-day model on simulating the long time series of glacier mass balance, we apply a degree-day model to simulate the mass balance of Urumqi Glacier No. 1 for t...In order to verify the feasibility and stability of a degree-day model on simulating the long time series of glacier mass balance, we apply a degree-day model to simulate the mass balance of Urumqi Glacier No. 1 for the period 1987/1988-2007/2008 based on temperature and precipitation data from a nearby climate station. The model is calibrated by simulating point measurements of mass bal- ance, mass balance profiles, and mean specific mass balance during 1987/1988-1996/1997. The opti- mized parameters are obtained by using a least square method to make the model fit the measured mass balance through the model calibration. The model validation （1997/1998-2007/2008） indicates that the modeled results are in good agreement with the observations. The static mass balance sensitiv- ity of Urumqi Glacier No. 1 is analyzed by computing the mass balance of the glacier for a temperature increase of 1℃, with and without a 5% precipitation increase, and the values for the east branch are -0.80 and -0.87 m w.e. a-1℃-1, respectively, and for the west branch, the values are -0.68 and -0.74 m w.e. a-1℃-1, respectively. Moreover, the analysis of the parameter stability indicates that the parame- ters in the model determined from the current climate condition can be applied in the prediction of the future mass balance changes for the glacier and provide a reference for extending the model to other small glaciers in western China.展开更多
Objective To optimize the extraction technology used for extracting active saponins from the roots, fibrous roots, basal part of stems, root verrucae, fruits, flowers, stems, and leaves of Panax notoginseng based on ...Objective To optimize the extraction technology used for extracting active saponins from the roots, fibrous roots, basal part of stems, root verrucae, fruits, flowers, stems, and leaves of Panax notoginseng based on the contents of ginsengsides Rg1, Rb1, and notoginsengside R1 as evaluation indexes. Methods Different parts of P. notoginseng were extracted by smashing tissue extraction (STE), ultrasound extraction, and reflux extraction. The contents of ginsengsides Rg1, Rb1, and notoginsengside R1 in 24 kinds of extracts were determined by HPLC-UV. Hypersil C18 column (200 mm × 4.6 mm, 5 μm) and acetonitrile-warter (20:80 for 30 min→45:55 for 18 min→70:30 for 2 min→80:20 for 10 min→100:0) were used; UV detector was set at 203 nm; The flow rate was set at 1.0 mL/min. Results STE was the most efficient technology with the highest yield of active saponins among the three tested extraction technologies. Conclusion STE is a fast, effective, and economical method to extract the active saponins from different parts of P. notoginseng. It could significantly shorten the extraction time and simplify the determination of the pre-processing work on identifying P. notoginseng. Such quick and effective extraction provides a powerful tool for analyzing P. notoginseng in the future.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.
基金supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (No. KZCX2-EW-311)the National Basic Research Program of China (No. 2007CB411501)the National Natural Science Foundation of China (Nos. 1141001040, J0930003/J0109)
文摘In order to verify the feasibility and stability of a degree-day model on simulating the long time series of glacier mass balance, we apply a degree-day model to simulate the mass balance of Urumqi Glacier No. 1 for the period 1987/1988-2007/2008 based on temperature and precipitation data from a nearby climate station. The model is calibrated by simulating point measurements of mass bal- ance, mass balance profiles, and mean specific mass balance during 1987/1988-1996/1997. The opti- mized parameters are obtained by using a least square method to make the model fit the measured mass balance through the model calibration. The model validation （1997/1998-2007/2008） indicates that the modeled results are in good agreement with the observations. The static mass balance sensitiv- ity of Urumqi Glacier No. 1 is analyzed by computing the mass balance of the glacier for a temperature increase of 1℃, with and without a 5% precipitation increase, and the values for the east branch are -0.80 and -0.87 m w.e. a-1℃-1, respectively, and for the west branch, the values are -0.68 and -0.74 m w.e. a-1℃-1, respectively. Moreover, the analysis of the parameter stability indicates that the parame- ters in the model determined from the current climate condition can be applied in the prediction of the future mass balance changes for the glacier and provide a reference for extending the model to other small glaciers in western China.
文摘Objective To optimize the extraction technology used for extracting active saponins from the roots, fibrous roots, basal part of stems, root verrucae, fruits, flowers, stems, and leaves of Panax notoginseng based on the contents of ginsengsides Rg1, Rb1, and notoginsengside R1 as evaluation indexes. Methods Different parts of P. notoginseng were extracted by smashing tissue extraction (STE), ultrasound extraction, and reflux extraction. The contents of ginsengsides Rg1, Rb1, and notoginsengside R1 in 24 kinds of extracts were determined by HPLC-UV. Hypersil C18 column (200 mm × 4.6 mm, 5 μm) and acetonitrile-warter (20:80 for 30 min→45:55 for 18 min→70:30 for 2 min→80:20 for 10 min→100:0) were used; UV detector was set at 203 nm; The flow rate was set at 1.0 mL/min. Results STE was the most efficient technology with the highest yield of active saponins among the three tested extraction technologies. Conclusion STE is a fast, effective, and economical method to extract the active saponins from different parts of P. notoginseng. It could significantly shorten the extraction time and simplify the determination of the pre-processing work on identifying P. notoginseng. Such quick and effective extraction provides a powerful tool for analyzing P. notoginseng in the future.
