目的初步探讨睾酮对红细胞衰亡影响的机制。方法1%健康人悬浮红细胞在3组不同的条件下体外培养:2种体外过氧化氢(H_(2)O_(2))诱导红细胞衰亡模型,包括3×10;mol/L睾酮+200μmol/L H_(2)O_(2)处理组(A组)、200μmol/L H_(2)O_(2)组(B...目的初步探讨睾酮对红细胞衰亡影响的机制。方法1%健康人悬浮红细胞在3组不同的条件下体外培养:2种体外过氧化氢(H_(2)O_(2))诱导红细胞衰亡模型,包括3×10;mol/L睾酮+200μmol/L H_(2)O_(2)处理组(A组)、200μmol/L H_(2)O_(2)组(B组)和1×PBS缓冲液对照组(C组)。于24和60 h时分别收集12孔板中红细胞(约2×10^(8)个/孔),通过流式细胞术检测红细胞衰亡率、活性氧(ROS)水平和钙离子水平([Ca^(2+)];),使用t检验比较分析各组检测指标的变化。结果A、B、C 3个组体外培养红细胞24和60 h红细胞衰亡率(%)2.61±0.28,11.25±1.43 vs 7.15±0.95,28.65±0.74 vs 1.32±0.07,8.18±0.08(P<0.01);ROS水平(%)14.52±0.68,15.26±0.49 vs 16.68±0.60,21.68±1.10 vs 7.61±0.21,10.29±1.06(P<0.01);[Ca^(2+)];(%)6.54±0.46,8.93±0.87 vs 11.78±0.76,14.63±0.80 vs 1.36±0.20,2.44±0.38(P<0.01)。加入睾酮H_(2)O_(2)组(A组)较H_(2)O_(2)处理组(B组)红细胞衰亡率、ROS水平及[Ca^(2+)];均以时间依赖的方式明显降低(P<0.01)。结论在体外H_(2)O_(2)诱导红细胞衰亡模型中,睾酮有效抑制了H_(2)O_(2)诱导的红细胞衰亡,其机制可能与减少ROS生成及维持正常[Ca^(2+)];有关。展开更多
The p53 protein is mutated or inactivated in more than 50% of human cancers, underscoring its cardinal importance as an oncosuppressor, p53 is expressed in all nucleated cells and can be activated by a plethora of pos...The p53 protein is mutated or inactivated in more than 50% of human cancers, underscoring its cardinal importance as an oncosuppressor, p53 is expressed in all nucleated cells and can be activated by a plethora of post-transcriptional modifications （in particular by the phosphorylation of critical serine residues）, as well as by the inhibition of its degradation （mainly mediated by the E3 ubiquitin ligase MDM2）. p53 was first characterized as a transcription factor that, once activated, drives the expression of gene programs causing a transient cell cycle arrest linked to DNA repair, a permanent and irreversible cell cycle arrest （senescence） or programmed cell death by apoptosis.展开更多
Short_day (SD) induced the plant senescence in pumpkin ( Cucurbita pepo Linn.) strain 185. Structural assay, gene expression and a series of biochemical analyses were performed to analyze the senescence mechanism...Short_day (SD) induced the plant senescence in pumpkin ( Cucurbita pepo Linn.) strain 185. Structural assay, gene expression and a series of biochemical analyses were performed to analyze the senescence mechanism in pumpkin strain 185 exposed to SD. Two aspects of important changes initiated in SD exposure contributed to the senescence process. SD functionally led to the initiation of the apical transformation from vegetative to reproductive growth, and then programmed cell death (PCD) in the apical meristem, causing the loss of vigorous growth activity. Moreover, SD treatment resulted in the formation of a great number of dying cells in mesophyll tissue later in the development compared with the phenotype of plants under long_day (LD) conditions. During the senescence process, high expression of nuclease is an important molecular event. These results indicate that the initiation of senescence process in pumpkin stain 185 plants is closely related to the death of cells in apical meristem and mesophyll.展开更多
Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice ( Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morpho...Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice ( Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morphological features of PCD have been found in the developing starchy endosperm cells, e.g. nucleus deformation, chromatin condensation, nuclear envelope disruption, and nuclear matrix leakage. DNA ladder displayed a smear of large DNA fragments from nucleus and evident bands of small DNA fragments (140-180 bp) from both nucleus and cytoplasm. In contrast with the rapid nucleus degradation, cell organelles in cytoplasm, such as rough endoplasmic reticulum, amyloplast, and mitochondrion, maintained their metabolic functions for a longer time. Seed reserves were continually synthesized and accumulated in the starchy endosperm cells despite the nucleus degradation during the PCD process. These results suggest that starchy endosperm cells remain active during reserve material synthesis and accumulation in the PCD process. The specific relationships between nucleus and cytoplasm in the developing endosperm cells and the morphological changes of nucleus in the endosperm PCD process were also discussed.展开更多
Aim In this study, we investigated the changes of lymphocyte subpopulationand apoptosis process of lymphocytes in the elderly, and the modulatory effect of pollen extract(PE) on apoptosis. Methods Lymphocyte phenotype...Aim In this study, we investigated the changes of lymphocyte subpopulationand apoptosis process of lymphocytes in the elderly, and the modulatory effect of pollen extract(PE) on apoptosis. Methods Lymphocyte phenotypes were detected using indirect immunofluorescencetechnique. The proliferation responses were determined by MTT method. Flow cytometry and automaticimage analysis were performed to evaluate the apoptosis of lymphocytes. Results The proliferationresponses of lymphocytes in the elderly were lower than that in young adults. Decreased CD_(45) RA^+cells and increased CD_(45) RO^+ cells were found in lymphocyte population of aged people, comparedwith that of young adults. The CD_(45) RO^+ cells were prone to apoptosis. There is an inhibitoryeffect of PE on apoptosis of lymphocytes in the elderly. Conclusion It is implied that thesusceptibility of lymphocyte in the elderly to apoptosis depends on activation, so called,activation-induced cell death. Present results suggest that apoptosis of lymphocytes in aged peopleplay an important role in the pathogenesis of immunosenescence. Thus, a possibility is open fordevelopment of apoptosis-modulating drugs from pollen.展开更多
文摘目的初步探讨睾酮对红细胞衰亡影响的机制。方法1%健康人悬浮红细胞在3组不同的条件下体外培养:2种体外过氧化氢(H_(2)O_(2))诱导红细胞衰亡模型,包括3×10;mol/L睾酮+200μmol/L H_(2)O_(2)处理组(A组)、200μmol/L H_(2)O_(2)组(B组)和1×PBS缓冲液对照组(C组)。于24和60 h时分别收集12孔板中红细胞(约2×10^(8)个/孔),通过流式细胞术检测红细胞衰亡率、活性氧(ROS)水平和钙离子水平([Ca^(2+)];),使用t检验比较分析各组检测指标的变化。结果A、B、C 3个组体外培养红细胞24和60 h红细胞衰亡率(%)2.61±0.28,11.25±1.43 vs 7.15±0.95,28.65±0.74 vs 1.32±0.07,8.18±0.08(P<0.01);ROS水平(%)14.52±0.68,15.26±0.49 vs 16.68±0.60,21.68±1.10 vs 7.61±0.21,10.29±1.06(P<0.01);[Ca^(2+)];(%)6.54±0.46,8.93±0.87 vs 11.78±0.76,14.63±0.80 vs 1.36±0.20,2.44±0.38(P<0.01)。加入睾酮H_(2)O_(2)组(A组)较H_(2)O_(2)处理组(B组)红细胞衰亡率、ROS水平及[Ca^(2+)];均以时间依赖的方式明显降低(P<0.01)。结论在体外H_(2)O_(2)诱导红细胞衰亡模型中,睾酮有效抑制了H_(2)O_(2)诱导的红细胞衰亡,其机制可能与减少ROS生成及维持正常[Ca^(2+)];有关。
文摘The p53 protein is mutated or inactivated in more than 50% of human cancers, underscoring its cardinal importance as an oncosuppressor, p53 is expressed in all nucleated cells and can be activated by a plethora of post-transcriptional modifications （in particular by the phosphorylation of critical serine residues）, as well as by the inhibition of its degradation （mainly mediated by the E3 ubiquitin ligase MDM2）. p53 was first characterized as a transcription factor that, once activated, drives the expression of gene programs causing a transient cell cycle arrest linked to DNA repair, a permanent and irreversible cell cycle arrest （senescence） or programmed cell death by apoptosis.
文摘Short_day (SD) induced the plant senescence in pumpkin ( Cucurbita pepo Linn.) strain 185. Structural assay, gene expression and a series of biochemical analyses were performed to analyze the senescence mechanism in pumpkin strain 185 exposed to SD. Two aspects of important changes initiated in SD exposure contributed to the senescence process. SD functionally led to the initiation of the apical transformation from vegetative to reproductive growth, and then programmed cell death (PCD) in the apical meristem, causing the loss of vigorous growth activity. Moreover, SD treatment resulted in the formation of a great number of dying cells in mesophyll tissue later in the development compared with the phenotype of plants under long_day (LD) conditions. During the senescence process, high expression of nuclease is an important molecular event. These results indicate that the initiation of senescence process in pumpkin stain 185 plants is closely related to the death of cells in apical meristem and mesophyll.
文摘Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice ( Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morphological features of PCD have been found in the developing starchy endosperm cells, e.g. nucleus deformation, chromatin condensation, nuclear envelope disruption, and nuclear matrix leakage. DNA ladder displayed a smear of large DNA fragments from nucleus and evident bands of small DNA fragments (140-180 bp) from both nucleus and cytoplasm. In contrast with the rapid nucleus degradation, cell organelles in cytoplasm, such as rough endoplasmic reticulum, amyloplast, and mitochondrion, maintained their metabolic functions for a longer time. Seed reserves were continually synthesized and accumulated in the starchy endosperm cells despite the nucleus degradation during the PCD process. These results suggest that starchy endosperm cells remain active during reserve material synthesis and accumulation in the PCD process. The specific relationships between nucleus and cytoplasm in the developing endosperm cells and the morphological changes of nucleus in the endosperm PCD process were also discussed.
文摘Aim In this study, we investigated the changes of lymphocyte subpopulationand apoptosis process of lymphocytes in the elderly, and the modulatory effect of pollen extract(PE) on apoptosis. Methods Lymphocyte phenotypes were detected using indirect immunofluorescencetechnique. The proliferation responses were determined by MTT method. Flow cytometry and automaticimage analysis were performed to evaluate the apoptosis of lymphocytes. Results The proliferationresponses of lymphocytes in the elderly were lower than that in young adults. Decreased CD_(45) RA^+cells and increased CD_(45) RO^+ cells were found in lymphocyte population of aged people, comparedwith that of young adults. The CD_(45) RO^+ cells were prone to apoptosis. There is an inhibitoryeffect of PE on apoptosis of lymphocytes in the elderly. Conclusion It is implied that thesusceptibility of lymphocyte in the elderly to apoptosis depends on activation, so called,activation-induced cell death. Present results suggest that apoptosis of lymphocytes in aged peopleplay an important role in the pathogenesis of immunosenescence. Thus, a possibility is open fordevelopment of apoptosis-modulating drugs from pollen.
