OBJECTIVE To study the anti-tumor effect of arsenic trioxide on the HepG2 human hepatocellular carcinoma cell line, and to explore its mechanism of action. METHODS The MTT assay was used to determine the inhibitory ef...OBJECTIVE To study the anti-tumor effect of arsenic trioxide on the HepG2 human hepatocellular carcinoma cell line, and to explore its mechanism of action. METHODS The MTT assay was used to determine the inhibitory effect of As2O3 on HepG2 cells at various As2O3 concentrations. The expression of p-JNK, caspase-3 and PARP was detected by Western blots. RESULTS As2O3 markedly inhibited the growth of the HepG2 cells and induced apoptosis. The results of Western blot analysis showed that the As2O3-induced apoptosis was accompanied by caspase-3 and PARP activation. p-JNK was detected at 10 min following As2O3 treatment, and preceded to peak at 20 min, and decreased by 30 min. The total protein content did not obviously change. The activation of JNK occurred prior to cell apoptosis. SP600125, a JNK inhibitor, suppressed the As2O3-induced activation of caspase-3 and PARP cleavage. CONCLUSION As2O3 inhibits the proliferation of human HepG2 hepatocellular carcinoma cells by inducing apoptosis in vitro. As2O3-induced apoptosis is accessed through the caspase-3 pathway. The JNK signal-transduction pathway and caspase-3 are involved upstream in the As2O3 induced HepG2 apoptotic response.展开更多
Concrete structures in main coal cleaning plants have been rebuilt and reinforced in the coal mines of the Shanghai Datun Energy Sources Co. Ltd., the first colliery of the Pingdingshan Coal Co. Ltd. and the Sanhejian...Concrete structures in main coal cleaning plants have been rebuilt and reinforced in the coal mines of the Shanghai Datun Energy Sources Co. Ltd., the first colliery of the Pingdingshan Coal Co. Ltd. and the Sanhejian mine of the Xuzhou Mining Group Co. Ltd. In these projects, the operating environment and reliability of concrete structures in the main plants of the three companies were investigated and the safety of the structures inspected. Qualitative and quantitative analyses were made on the special natural, technological and mechanical environments around the structures. On the basis of these analyses, we discuss the long-term, combined actions of the harsh natural (corrosive gases, liquids and solids) and mechanical environments on concrete structures and further investigated the damage and deteriorating mechanisms and curing techniques of concrete structures in the main coal cleaning plants. Our study can provide a theoretical basis for ensuring the reliability of concrete structures in main coal cleaning plants.展开更多
River basin reservoir construction affects water and sediment transport processes in downstream reaches. The downstream impact of the Three Gorges Projects （TGP） has started to become apparent： （1） reduction in f...River basin reservoir construction affects water and sediment transport processes in downstream reaches. The downstream impact of the Three Gorges Projects （TGP） has started to become apparent： （1） reduction in flood duration and discharge, and significant reduction in sediment load. Although there was some restoration in downstream sediment load, the total amount did not exceed the pre-impoundment annual average; （2） in 2003-2014 the d 〉 0.125 mm （coarse sand） load was restored to some degree, and to a maximum at Jianli Station, which was mainly at the pre-impoundment average. After restoration, erosion and deposition characteristics of the sediment was identical to that before impoundment. The degree of restoration during 2008-2014 was less than during 2003-2007; （3） after TGP im- poundment, there was some restoration in d 〈 0.125 mm （fine sand） sediment load, however, it was {ower than the pre-impoundment average; （4） due to riverbed compensation, the d 〉 0.125 mm sediment load recovered to a certain degree after impoundment, however, the total did not exceed 4400x104 t/y. This was mainly limited by flood duration and the average flow rate, and was less affected by upstream main stream, tributaries, or lakes. Restoration of d 〈 0.125 mm suspended sediment was largely controlled by upstream main stream, tributaries, and lakes, as well as by riverbed compensation. Due to bed armoring, riverbed fine suspended sediment compensation capability was weakened; （5） during 2003-2007 and 2008-2014, Yichang to Zhicheng and upper Jingjiang experienced coarse and fine erosion,lower Jingjiang experienced coarse deposition and fine erosion, Hankou to Datong had coarse deposition and fine erosion, and Chenglingji and Hankou was characterized by coarse deposition and fine sand erosion in 2003-2007, and coarse and fine erosion in 2008-2014. This difference was controlled by flood duration and number at Luoshan Station.展开更多
The system energy of H atom occupying different positions in Cr2O3 crystal lattice is calculated by adopting the first-principles calculation method based on density functional theory in this paper. The results indica...The system energy of H atom occupying different positions in Cr2O3 crystal lattice is calculated by adopting the first-principles calculation method based on density functional theory in this paper. The results indicate that the most stable position of H atom in Cr2O3 crystal lattice locates at the bilateral positions of the center of the unoccupied O octahedral interstice. The reason resulting in this situation is analyzed by comparing the change of Cr2O3 lattice distortion and density of states in Cr2O3_H system when H atom locates at different positions in octahedral interstice. The diffusion activation energy of H atom is 0.73 eV,which is determined by seeking the diffusion path and transition state of H atom in Cr2O3 crystal lattice. The effective attempt frequency of H atom in Cr2O3 crystal lattice is also calculated by using molecular dynamics. Combining with diffusion activation energy data,the diffusion coefficient of H atom in Cr2O3 crystal is determined.展开更多
基金supported by a grant from theNational Natural Science Foundation of China(No.30572114).
文摘OBJECTIVE To study the anti-tumor effect of arsenic trioxide on the HepG2 human hepatocellular carcinoma cell line, and to explore its mechanism of action. METHODS The MTT assay was used to determine the inhibitory effect of As2O3 on HepG2 cells at various As2O3 concentrations. The expression of p-JNK, caspase-3 and PARP was detected by Western blots. RESULTS As2O3 markedly inhibited the growth of the HepG2 cells and induced apoptosis. The results of Western blot analysis showed that the As2O3-induced apoptosis was accompanied by caspase-3 and PARP activation. p-JNK was detected at 10 min following As2O3 treatment, and preceded to peak at 20 min, and decreased by 30 min. The total protein content did not obviously change. The activation of JNK occurred prior to cell apoptosis. SP600125, a JNK inhibitor, suppressed the As2O3-induced activation of caspase-3 and PARP cleavage. CONCLUSION As2O3 inhibits the proliferation of human HepG2 hepatocellular carcinoma cells by inducing apoptosis in vitro. As2O3-induced apoptosis is accessed through the caspase-3 pathway. The JNK signal-transduction pathway and caspase-3 are involved upstream in the As2O3 induced HepG2 apoptotic response.
基金Project BK2008128 supported by the Natural Science Foundation of Jiangsu Province
文摘Concrete structures in main coal cleaning plants have been rebuilt and reinforced in the coal mines of the Shanghai Datun Energy Sources Co. Ltd., the first colliery of the Pingdingshan Coal Co. Ltd. and the Sanhejian mine of the Xuzhou Mining Group Co. Ltd. In these projects, the operating environment and reliability of concrete structures in the main plants of the three companies were investigated and the safety of the structures inspected. Qualitative and quantitative analyses were made on the special natural, technological and mechanical environments around the structures. On the basis of these analyses, we discuss the long-term, combined actions of the harsh natural (corrosive gases, liquids and solids) and mechanical environments on concrete structures and further investigated the damage and deteriorating mechanisms and curing techniques of concrete structures in the main coal cleaning plants. Our study can provide a theoretical basis for ensuring the reliability of concrete structures in main coal cleaning plants.
基金National Natural Science Foundation of China,No.51479146,No.51579123,No.51509012Fundamental Research Funds for Central Welfare Research Institutes,No.TKS160103+2 种基金No.TKS150102The National Key Research&Development Programs,No.2013BAB12B01National Key Research Program of China,No.2016YFC0402106
文摘River basin reservoir construction affects water and sediment transport processes in downstream reaches. The downstream impact of the Three Gorges Projects （TGP） has started to become apparent： （1） reduction in flood duration and discharge, and significant reduction in sediment load. Although there was some restoration in downstream sediment load, the total amount did not exceed the pre-impoundment annual average; （2） in 2003-2014 the d 〉 0.125 mm （coarse sand） load was restored to some degree, and to a maximum at Jianli Station, which was mainly at the pre-impoundment average. After restoration, erosion and deposition characteristics of the sediment was identical to that before impoundment. The degree of restoration during 2008-2014 was less than during 2003-2007; （3） after TGP im- poundment, there was some restoration in d 〈 0.125 mm （fine sand） sediment load, however, it was {ower than the pre-impoundment average; （4） due to riverbed compensation, the d 〉 0.125 mm sediment load recovered to a certain degree after impoundment, however, the total did not exceed 4400x104 t/y. This was mainly limited by flood duration and the average flow rate, and was less affected by upstream main stream, tributaries, or lakes. Restoration of d 〈 0.125 mm suspended sediment was largely controlled by upstream main stream, tributaries, and lakes, as well as by riverbed compensation. Due to bed armoring, riverbed fine suspended sediment compensation capability was weakened; （5） during 2003-2007 and 2008-2014, Yichang to Zhicheng and upper Jingjiang experienced coarse and fine erosion,lower Jingjiang experienced coarse deposition and fine erosion, Hankou to Datong had coarse deposition and fine erosion, and Chenglingji and Hankou was characterized by coarse deposition and fine sand erosion in 2003-2007, and coarse and fine erosion in 2008-2014. This difference was controlled by flood duration and number at Luoshan Station.
基金supported by the National Natural Science Foundation of China (Grant Nos.50771104,50871122)
文摘The system energy of H atom occupying different positions in Cr2O3 crystal lattice is calculated by adopting the first-principles calculation method based on density functional theory in this paper. The results indicate that the most stable position of H atom in Cr2O3 crystal lattice locates at the bilateral positions of the center of the unoccupied O octahedral interstice. The reason resulting in this situation is analyzed by comparing the change of Cr2O3 lattice distortion and density of states in Cr2O3_H system when H atom locates at different positions in octahedral interstice. The diffusion activation energy of H atom is 0.73 eV,which is determined by seeking the diffusion path and transition state of H atom in Cr2O3 crystal lattice. The effective attempt frequency of H atom in Cr2O3 crystal lattice is also calculated by using molecular dynamics. Combining with diffusion activation energy data,the diffusion coefficient of H atom in Cr2O3 crystal is determined.
