Leading by cytotoxicity against HepG2 cells,bioactivity-guided fractionation of the EtOAc fraction from Artemisia atrovirens led to the isolation of 18 new guaianolide dimers,artematrolides A-R and lavandiolides A,B,C...Leading by cytotoxicity against HepG2 cells,bioactivity-guided fractionation of the EtOAc fraction from Artemisia atrovirens led to the isolation of 18 new guaianolide dimers,artematrolides A-R and lavandiolides A,B,C,H,and J.Eight compounds(1,4,10,12,13,and 19-21) were unambiguously confirmed by the single-crystal X-ray diffraction analyses,and the others were elucidated based on IR,UV,HRESIMS,1 D and 2 D NMR experiments,and comparison of the experimental and calculated ECD data.Structurally,all of them were [4+2] Diels-Alder adducts of two monomeric guaianolides.The isolates were evaluated for their cytotoxicity against three human hepatoma cell lines,and 19 compounds demonstrated cytotoxicity against HepG2,SMMC-7721,and Huh7 cell lines.Especially,compounds 1,12,14,and 15 exhibited cytotoxicity with IC50 values of 4.4,3.8,7.6,and 6.7 μmol/L(HepG2),9.6,4.6,6.6,and 6.0 μmol/L(SMMC-7721),and 7.6,4.5,6.9,and 5.6 μmol/L(Huh7),respectively.Notably,compound 12 showed the most promising activity against three human hepatoma cell lines and dose-dependently inhibited cell migration and invasion,induced G2/M cell cycle arrest and cell apoptosis in HepG2 cells,down-regulated the expression of BCL-2 and PARP-1,and activated PARP-1 to up-regulate the expression of cleaved-PARP-1.展开更多
Zika virus(ZIKV),a positive-sense single-stranded RNA virus,causes congenital ZIKV syndrome in children and Guillain-Barre Syndrome(GBS)in adults.ZIKV expresses nonstructural protein 5(NS5),a large protein that is ess...Zika virus(ZIKV),a positive-sense single-stranded RNA virus,causes congenital ZIKV syndrome in children and Guillain-Barre Syndrome(GBS)in adults.ZIKV expresses nonstructural protein 5(NS5),a large protein that is essential for viral replication.ZIKV NS5 confers the ability to evade interferon(IFN)signalling;however,the exact mechanism remains unclear.In this study,we employed affinity pull-down and liquid chromatography-tandem mass spectrometry(LC-MS/MS)analyses and found that splicing factor 3b subunit 3(SF3B3)is associated with the NS5-Flag pull-down complex through interaction with NS5.Functional assays showed that SF3B3 overexpression inhibited ZIKV replication by promoting IFN-stimulated gene(ISG)expression whereas silencing of SF3B3 inhibited expression of ISGs to promote ZIKV replication.GTP cyclohydrolase I(GCH1)is the first and ratelimiting enzyme in tetrahydrobiopterin(BH4)biosynthesis.NS5 upregulates the expression of GCH1 during ZIKV infection.And GCH1 marginally promoted ZIKV replication via the IFN pathway.Additionally,GCH1 expression is related to the regulation of SF3B3.Overexpression of the SF3B3 protein effectively reduced GCH1 protein levels,whereas SF3B3 knockdown increased its levels.These findings indicated that ZIKV NS5 binding protein SF3B3 contributed to the host immune response against ZIKV replication by modulating the expression of GCH1.展开更多
In recent years, China’s industrialization and urbanization have deepened, and the economy has grown considerably. But at the same time, they have also brought about many environmental problems. As a pillar of the na...In recent years, China’s industrialization and urbanization have deepened, and the economy has grown considerably. But at the same time, they have also brought about many environmental problems. As a pillar of the national economy, the iron and steel(IS) industry is one of the most emitting and energy-consuming sub-sectors of the industrial sector. It is also one of the industries with the most severe overcapacity problem in China. In this paper, we explore the impact of capacity utilization on carbon dioxide emission based on panel data of China’s iron and steel industry from 2005 to 2014. We also tested the heterogeneity in different regions and different sub-samples. Results show that capacity utilization and carbon dioxide emission are positively correlated. However, the impact of capacity utilization on carbon dioxide emission differs when considering regional heterogeneity. Results in all three regions show a positive relationship between capacity utilization and carbon dioxide emission,but the impact intensity is strongest in the western region, followed by the eastern and central regions.Moreover, capacity utilization impacts carbon dioxide emission by influencing firm numbers in the iron and steel industry and energy consumption. Further analysis shows that there exists a threshold effect in different stages of energy consumption and energy structure. Finally, some findings and practical policy recommendations are provided.展开更多
基金supported by the Yunnan Wanren Project (YNWRKJLJ-2019-002)the Program of Yunling Scholarship (Ji-Jun, Chen)the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in Yunnan Province (Changan, Geng)。
文摘Leading by cytotoxicity against HepG2 cells,bioactivity-guided fractionation of the EtOAc fraction from Artemisia atrovirens led to the isolation of 18 new guaianolide dimers,artematrolides A-R and lavandiolides A,B,C,H,and J.Eight compounds(1,4,10,12,13,and 19-21) were unambiguously confirmed by the single-crystal X-ray diffraction analyses,and the others were elucidated based on IR,UV,HRESIMS,1 D and 2 D NMR experiments,and comparison of the experimental and calculated ECD data.Structurally,all of them were [4+2] Diels-Alder adducts of two monomeric guaianolides.The isolates were evaluated for their cytotoxicity against three human hepatoma cell lines,and 19 compounds demonstrated cytotoxicity against HepG2,SMMC-7721,and Huh7 cell lines.Especially,compounds 1,12,14,and 15 exhibited cytotoxicity with IC50 values of 4.4,3.8,7.6,and 6.7 μmol/L(HepG2),9.6,4.6,6.6,and 6.0 μmol/L(SMMC-7721),and 7.6,4.5,6.9,and 5.6 μmol/L(Huh7),respectively.Notably,compound 12 showed the most promising activity against three human hepatoma cell lines and dose-dependently inhibited cell migration and invasion,induced G2/M cell cycle arrest and cell apoptosis in HepG2 cells,down-regulated the expression of BCL-2 and PARP-1,and activated PARP-1 to up-regulate the expression of cleaved-PARP-1.
基金supported by the National Key R&D Project of China(2021YFC230170402)CAMS Innovation Fund for Medical Sciences(2021-1-I2M-038).
文摘Zika virus(ZIKV),a positive-sense single-stranded RNA virus,causes congenital ZIKV syndrome in children and Guillain-Barre Syndrome(GBS)in adults.ZIKV expresses nonstructural protein 5(NS5),a large protein that is essential for viral replication.ZIKV NS5 confers the ability to evade interferon(IFN)signalling;however,the exact mechanism remains unclear.In this study,we employed affinity pull-down and liquid chromatography-tandem mass spectrometry(LC-MS/MS)analyses and found that splicing factor 3b subunit 3(SF3B3)is associated with the NS5-Flag pull-down complex through interaction with NS5.Functional assays showed that SF3B3 overexpression inhibited ZIKV replication by promoting IFN-stimulated gene(ISG)expression whereas silencing of SF3B3 inhibited expression of ISGs to promote ZIKV replication.GTP cyclohydrolase I(GCH1)is the first and ratelimiting enzyme in tetrahydrobiopterin(BH4)biosynthesis.NS5 upregulates the expression of GCH1 during ZIKV infection.And GCH1 marginally promoted ZIKV replication via the IFN pathway.Additionally,GCH1 expression is related to the regulation of SF3B3.Overexpression of the SF3B3 protein effectively reduced GCH1 protein levels,whereas SF3B3 knockdown increased its levels.These findings indicated that ZIKV NS5 binding protein SF3B3 contributed to the host immune response against ZIKV replication by modulating the expression of GCH1.
基金Supported by National Natural Science Foundation of China (72071067, 71601064, 71801067)。
文摘In recent years, China’s industrialization and urbanization have deepened, and the economy has grown considerably. But at the same time, they have also brought about many environmental problems. As a pillar of the national economy, the iron and steel(IS) industry is one of the most emitting and energy-consuming sub-sectors of the industrial sector. It is also one of the industries with the most severe overcapacity problem in China. In this paper, we explore the impact of capacity utilization on carbon dioxide emission based on panel data of China’s iron and steel industry from 2005 to 2014. We also tested the heterogeneity in different regions and different sub-samples. Results show that capacity utilization and carbon dioxide emission are positively correlated. However, the impact of capacity utilization on carbon dioxide emission differs when considering regional heterogeneity. Results in all three regions show a positive relationship between capacity utilization and carbon dioxide emission,but the impact intensity is strongest in the western region, followed by the eastern and central regions.Moreover, capacity utilization impacts carbon dioxide emission by influencing firm numbers in the iron and steel industry and energy consumption. Further analysis shows that there exists a threshold effect in different stages of energy consumption and energy structure. Finally, some findings and practical policy recommendations are provided.
