OBJECTIVE To investigate whether aldo-keto reductases(AKRs)can act as a nitrore⁃ductase(NR)and bioactivate aristolochic acidⅠ(AA-Ⅰ)to produce AA-Ⅰ-DNA adducts.METHODS①Human-induced hepatocytes(hiHeps)and human bla...OBJECTIVE To investigate whether aldo-keto reductases(AKRs)can act as a nitrore⁃ductase(NR)and bioactivate aristolochic acidⅠ(AA-Ⅰ)to produce AA-Ⅰ-DNA adducts.METHODS①Human-induced hepatocytes(hiHeps)and human bladder RT4 cells were used as tool cells and treated with AA-Ⅰ0,0.5,1.0 and 2μmol·L^(-1)for 24 h.Cell viability was detected using the CCK-8 method,and the half maximal inhibition concentration(IC_(50))was calculated using the CCK-8 method and the level of DNA adduct production was calculated.②hiHeps and RT4 cells were treated with AKR inhibitor luteotin(0,5,10 and 25μmol·L^(-1))+AA-Ⅰ0.2 and 1.0μmol·L^(-1)for 24 h,respectively,and the levels of DNA adducts were detected by a liquid chromatography-tandem mass spectrometer(LC-MS/MS).③hiHeps cells were incubated with 80 nmol·L^(-1)small interfering RNAs(si-AKRs)for 48 h and treated with AA-Ⅰ1.0μmol·L^(-1)for 24 h.Real-time qualitative PCR(RT-qPCR)method was used to detect the mRNA expression of AKRs gene and LC-MS/MS technology was used to investigate the effect of specific AKR gene knockdown on DNA adduct levels.④500 nmol·L^(-1)human AKR recombinant proteins AKR1A1 and AA-Ⅰwere incubated in vitro under anaerobic conditions and the formation of AA-Ⅰ-DNA adducts was detected.RESULTS①The IC_(50)of AA-Ⅰto hiHeps and RT4 cells was 1.9 and 0.42μmol·L^(-1),respec⁃tively.The level of DNA adduct production of the two cell lines was significantly different(P<0.01).②Luteolin≥5μmol·L^(-1)significantly inhibited the production of AA-Ⅰ-DNA adducts in both cells(P<0.05),and there was a concentration-dependent effect in hiHeps cells(P<0.01,R=0.84).③In the AKR family,the knockdown of AKR1A1 gene up to 80%inhibited the generation of AA-Ⅰ-DNA adducts by 30%-40%.④The AA-Ⅰ-DNA adducts were detected in the incubation of recombinant protein AKR1A1 and AA-Ⅰunder anaerobic conditions in vitro,approximately 1 adduct per 107 nucleotides.CONCLU⁃SION AKR1A1 is involved in AA-Ⅰbioactivation,providing a reference for elucidation of the carcino⁃genic mechanism of AA-Ⅰ.展开更多
以某版高中英语教材中阅读语篇“The Old Man and the Sea”为例,从名著作家介绍、小说要素梳理、写作风格鉴赏、人物性格推断、文学特质分析、课堂评价设计等方面阐述“教、学、评一体化”的文学阅读教学的实施。并且,对此理念下的高...以某版高中英语教材中阅读语篇“The Old Man and the Sea”为例,从名著作家介绍、小说要素梳理、写作风格鉴赏、人物性格推断、文学特质分析、课堂评价设计等方面阐述“教、学、评一体化”的文学阅读教学的实施。并且,对此理念下的高中英语文学阅读教学实践进行反思,提出教师应融多元主体评价于文学作品阅读课堂全程,关注即时生成,及时反馈评价,提升教师课程、评价与文学素养,有效发展学生的英语学科核心素养。展开更多
Through investigating the population change of Cinnamomum camphora(L.) Presl. in Wuxi City, the research found that C. camphora(L.) Presl. in the past century had already become common species from rare species, then ...Through investigating the population change of Cinnamomum camphora(L.) Presl. in Wuxi City, the research found that C. camphora(L.) Presl. in the past century had already become common species from rare species, then explored the causes, advantages and disadvantages of the change. In view of sustainable development of urban greening, zonal vegetation and fl ora, this paper explored the scientifi c and reasonable application of tree species and also protection of urban plant diversity.展开更多
文摘OBJECTIVE To investigate whether aldo-keto reductases(AKRs)can act as a nitrore⁃ductase(NR)and bioactivate aristolochic acidⅠ(AA-Ⅰ)to produce AA-Ⅰ-DNA adducts.METHODS①Human-induced hepatocytes(hiHeps)and human bladder RT4 cells were used as tool cells and treated with AA-Ⅰ0,0.5,1.0 and 2μmol·L^(-1)for 24 h.Cell viability was detected using the CCK-8 method,and the half maximal inhibition concentration(IC_(50))was calculated using the CCK-8 method and the level of DNA adduct production was calculated.②hiHeps and RT4 cells were treated with AKR inhibitor luteotin(0,5,10 and 25μmol·L^(-1))+AA-Ⅰ0.2 and 1.0μmol·L^(-1)for 24 h,respectively,and the levels of DNA adducts were detected by a liquid chromatography-tandem mass spectrometer(LC-MS/MS).③hiHeps cells were incubated with 80 nmol·L^(-1)small interfering RNAs(si-AKRs)for 48 h and treated with AA-Ⅰ1.0μmol·L^(-1)for 24 h.Real-time qualitative PCR(RT-qPCR)method was used to detect the mRNA expression of AKRs gene and LC-MS/MS technology was used to investigate the effect of specific AKR gene knockdown on DNA adduct levels.④500 nmol·L^(-1)human AKR recombinant proteins AKR1A1 and AA-Ⅰwere incubated in vitro under anaerobic conditions and the formation of AA-Ⅰ-DNA adducts was detected.RESULTS①The IC_(50)of AA-Ⅰto hiHeps and RT4 cells was 1.9 and 0.42μmol·L^(-1),respec⁃tively.The level of DNA adduct production of the two cell lines was significantly different(P<0.01).②Luteolin≥5μmol·L^(-1)significantly inhibited the production of AA-Ⅰ-DNA adducts in both cells(P<0.05),and there was a concentration-dependent effect in hiHeps cells(P<0.01,R=0.84).③In the AKR family,the knockdown of AKR1A1 gene up to 80%inhibited the generation of AA-Ⅰ-DNA adducts by 30%-40%.④The AA-Ⅰ-DNA adducts were detected in the incubation of recombinant protein AKR1A1 and AA-Ⅰunder anaerobic conditions in vitro,approximately 1 adduct per 107 nucleotides.CONCLU⁃SION AKR1A1 is involved in AA-Ⅰbioactivation,providing a reference for elucidation of the carcino⁃genic mechanism of AA-Ⅰ.
文摘以某版高中英语教材中阅读语篇“The Old Man and the Sea”为例,从名著作家介绍、小说要素梳理、写作风格鉴赏、人物性格推断、文学特质分析、课堂评价设计等方面阐述“教、学、评一体化”的文学阅读教学的实施。并且,对此理念下的高中英语文学阅读教学实践进行反思,提出教师应融多元主体评价于文学作品阅读课堂全程,关注即时生成,及时反馈评价,提升教师课程、评价与文学素养,有效发展学生的英语学科核心素养。
文摘Through investigating the population change of Cinnamomum camphora(L.) Presl. in Wuxi City, the research found that C. camphora(L.) Presl. in the past century had already become common species from rare species, then explored the causes, advantages and disadvantages of the change. In view of sustainable development of urban greening, zonal vegetation and fl ora, this paper explored the scientifi c and reasonable application of tree species and also protection of urban plant diversity.
