利用神舟8号飞船的SIMBOX发射机会,对真实微重力影响裸藻光合作用活性进行了研究.我们发现,微重力降低了光合活性(Fv/Fm),提高了细胞内叶绿素a和胡萝卜素含量.快速叶绿素荧光动力学研究显示微重力降低了叶绿素荧光强度,但快速叶绿素荧...利用神舟8号飞船的SIMBOX发射机会,对真实微重力影响裸藻光合作用活性进行了研究.我们发现,微重力降低了光合活性(Fv/Fm),提高了细胞内叶绿素a和胡萝卜素含量.快速叶绿素荧光动力学研究显示微重力降低了叶绿素荧光强度,但快速叶绿素荧光动力学曲线的形状(O-J-I-P)没有改变.在微重力处理下裸藻的最大光化学效率(φPo)、用于电子传递的量子产额(φEo)和光合作用性能指数(PIABS and PICS)都明显降低,但单位反应中心吸收的光能(ABS/RC)和单位反应中心耗散的能量(DIo/RC)都明显升高.77K低温荧光光谱实现微重力改变了能量在PSⅠ和PSⅡ之间的分配并出现了红移现象.这些结果表明真实微重力降低光合作用的活性有可能通过两个途径,即抑制裸藻抑制光合电子传递中PSⅡ的受体端和改变PSⅠ的结构从而引起流向PSⅠ的能量传递减少.展开更多
Objective:We explored the role and molecular mechanism of Microcystin-LR(MC-LR) in hepatocarcinogenesis.Methods:The two-stage-medium-term theory was applied to the establishment of the animal model.The promoting effec...Objective:We explored the role and molecular mechanism of Microcystin-LR(MC-LR) in hepatocarcinogenesis.Methods:The two-stage-medium-term theory was applied to the establishment of the animal model.The promoting effect of MC-LR on liver tumor was evaluated with the Albert γ-GT methods.During the tumor-promoting course,the effects of MC-LR on the regulation and expression of the Bcl-2 and Bax genes were studied with immunohistochemical technique and RT-PCR.Results:MCLR could enhance the positive reaction of Albert γ-GT(GGT),a preneoplasm marker.The positive reaction rate of GGT in diethylnitrosamine(DEN) + MC group was significantly higher than that in the DEN control group.The protein and RNA expression of Bcl-2 was significantly increased by MC-LR,and that the protein expression of Bax was decreased simultaneously.Conclusion:These results indicate that the MC-LR can inhabit apoptosis through the Bcl-2 and Bax genes.Therefore,we conclude that the expression change of Bcl-2 and Bax genes possibly plays an important role in the promotion of liver tumor by MC-LR.展开更多
基金supported by grants from The Chinese Natural Science Foundation(30970688)State Key Laboratory of Freshwater Ecology and Biotechnology(2016FBZ07)the Chinese Manned Spaceflight Project~~
文摘利用神舟8号飞船的SIMBOX发射机会,对真实微重力影响裸藻光合作用活性进行了研究.我们发现,微重力降低了光合活性(Fv/Fm),提高了细胞内叶绿素a和胡萝卜素含量.快速叶绿素荧光动力学研究显示微重力降低了叶绿素荧光强度,但快速叶绿素荧光动力学曲线的形状(O-J-I-P)没有改变.在微重力处理下裸藻的最大光化学效率(φPo)、用于电子传递的量子产额(φEo)和光合作用性能指数(PIABS and PICS)都明显降低,但单位反应中心吸收的光能(ABS/RC)和单位反应中心耗散的能量(DIo/RC)都明显升高.77K低温荧光光谱实现微重力改变了能量在PSⅠ和PSⅡ之间的分配并出现了红移现象.这些结果表明真实微重力降低光合作用的活性有可能通过两个途径,即抑制裸藻抑制光合电子传递中PSⅡ的受体端和改变PSⅠ的结构从而引起流向PSⅠ的能量传递减少.
基金Supported by grants from the Natural Science Foundation of Fujian Province (No C0710019)the Science & Technology Program of Fuzhou (No 2006S-G24)
文摘Objective:We explored the role and molecular mechanism of Microcystin-LR(MC-LR) in hepatocarcinogenesis.Methods:The two-stage-medium-term theory was applied to the establishment of the animal model.The promoting effect of MC-LR on liver tumor was evaluated with the Albert γ-GT methods.During the tumor-promoting course,the effects of MC-LR on the regulation and expression of the Bcl-2 and Bax genes were studied with immunohistochemical technique and RT-PCR.Results:MCLR could enhance the positive reaction of Albert γ-GT(GGT),a preneoplasm marker.The positive reaction rate of GGT in diethylnitrosamine(DEN) + MC group was significantly higher than that in the DEN control group.The protein and RNA expression of Bcl-2 was significantly increased by MC-LR,and that the protein expression of Bax was decreased simultaneously.Conclusion:These results indicate that the MC-LR can inhabit apoptosis through the Bcl-2 and Bax genes.Therefore,we conclude that the expression change of Bcl-2 and Bax genes possibly plays an important role in the promotion of liver tumor by MC-LR.
