目的:探讨染色体结构维持蛋白1A(structural maintenance of chromosome 1A,SMC1A)在乳腺癌中的表达情况,分析其与临床病理特征的相关性以及对乳腺癌细胞凋亡的影响。方法:利用癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库分析S...目的:探讨染色体结构维持蛋白1A(structural maintenance of chromosome 1A,SMC1A)在乳腺癌中的表达情况,分析其与临床病理特征的相关性以及对乳腺癌细胞凋亡的影响。方法:利用癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库分析SMC1A m RNA在乳腺癌及正常乳腺组织中的表达差异及其与乳腺癌预后的相关性。收集南京医科大学第一附属医院2023年1—12月间48例乳腺癌患者手术切除的癌组织和癌旁组织标本,采用实时荧光定量聚合酶链反应和免疫组织化学分析SMC1A的表达,并评估其与患者临床病理指标的关系。通过下调乳腺癌细胞系MCF-7中SMC1A表达,检测其凋亡相关蛋白的变化。结果:对TCGA相关转录组测序数据分析提示,SMC1A m RNA在乳腺癌组织中的表达显著高于正常乳腺组织,并与乳腺癌的预后紧密相关。临床样本验证也表明,SMC1A的表达水平在乳腺癌组织中显著高于癌旁组织,并与TNM分期、淋巴结转移及病理分化程度相关。siRNA介导的SMC1A下调在MCF-7细胞中显著提升了Cleaved-caspase-3、Cleaved-caspase-9及Bax的表达,降低了Bcl2的表达。结论:SMC1A在乳腺癌组织中高表达,并与乳腺癌的进展及病理分化有关。初步机制研究表明,SMC1A的表达调控可能对促进乳腺癌细胞凋亡具有重要作用。展开更多
This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanis...This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanism is presented to structure the adaptive integral terminal sliding mode control(SMC)strategy.The control design consists of compensation control and nominal control,which improves the rapidity and accuracy of trajectory tracking.The smooth saturation model based on the error function is applied to approximate the voltage saturation phenomenon.Additionally,to deal with the adverse effects of various unknown disturbances,including model parameter uncertainties and unknown external load disturbances,an improved disturbance observer(DO)is proposed.This observer effectively suppresses the fluctuations caused by fixed gain during the starting period of the system.Finally,the experimental results under different conditions show that the proposed strategy has good tracking and disturbance suppression performances.展开更多
真核生物集缩素(condensin)的主要作用是在细胞周期过程中调控染色体的动态变化。它是一种含5个亚基的蛋白质,由1个起核心催化作用的SMC2(structure maintenance of chromosomes 2)/SMC4异二聚体和3个起调节作用的非SMC亚基组成。目前,...真核生物集缩素(condensin)的主要作用是在细胞周期过程中调控染色体的动态变化。它是一种含5个亚基的蛋白质,由1个起核心催化作用的SMC2(structure maintenance of chromosomes 2)/SMC4异二聚体和3个起调节作用的非SMC亚基组成。目前,关于集缩素中SMC2/SMC4异二聚体的体内构象和分子作用机制仍不清楚。最近,对SMC2/SMC4异二聚体的结构解析取得许多新进展。该文在简要介绍SMC蛋白的基本结构、真核生物集缩素的发现、真核生物集缩素的结构组成的基础上,对近年来SMC2/SMC4异二聚体的结构解析的研究进展作一综述,以期为相关研究提供参考。展开更多
文摘目的:探讨染色体结构维持蛋白1A(structural maintenance of chromosome 1A,SMC1A)在乳腺癌中的表达情况,分析其与临床病理特征的相关性以及对乳腺癌细胞凋亡的影响。方法:利用癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库分析SMC1A m RNA在乳腺癌及正常乳腺组织中的表达差异及其与乳腺癌预后的相关性。收集南京医科大学第一附属医院2023年1—12月间48例乳腺癌患者手术切除的癌组织和癌旁组织标本,采用实时荧光定量聚合酶链反应和免疫组织化学分析SMC1A的表达,并评估其与患者临床病理指标的关系。通过下调乳腺癌细胞系MCF-7中SMC1A表达,检测其凋亡相关蛋白的变化。结果:对TCGA相关转录组测序数据分析提示,SMC1A m RNA在乳腺癌组织中的表达显著高于正常乳腺组织,并与乳腺癌的预后紧密相关。临床样本验证也表明,SMC1A的表达水平在乳腺癌组织中显著高于癌旁组织,并与TNM分期、淋巴结转移及病理分化程度相关。siRNA介导的SMC1A下调在MCF-7细胞中显著提升了Cleaved-caspase-3、Cleaved-caspase-9及Bax的表达,降低了Bcl2的表达。结论:SMC1A在乳腺癌组织中高表达,并与乳腺癌的进展及病理分化有关。初步机制研究表明,SMC1A的表达调控可能对促进乳腺癌细胞凋亡具有重要作用。
基金supported by the National Natural Science Foundation under Grant 62273189the Shandong Province Natural Science Foundation under Grant ZR2021MF005Systems Science Plus Joint Research Program of Qingdao University under Grant XT2024201 of China supporting this research work.
文摘This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor(PMSM)with stator voltage saturation and unknown load.A smooth switching mechanism is presented to structure the adaptive integral terminal sliding mode control(SMC)strategy.The control design consists of compensation control and nominal control,which improves the rapidity and accuracy of trajectory tracking.The smooth saturation model based on the error function is applied to approximate the voltage saturation phenomenon.Additionally,to deal with the adverse effects of various unknown disturbances,including model parameter uncertainties and unknown external load disturbances,an improved disturbance observer(DO)is proposed.This observer effectively suppresses the fluctuations caused by fixed gain during the starting period of the system.Finally,the experimental results under different conditions show that the proposed strategy has good tracking and disturbance suppression performances.
文摘真核生物集缩素(condensin)的主要作用是在细胞周期过程中调控染色体的动态变化。它是一种含5个亚基的蛋白质,由1个起核心催化作用的SMC2(structure maintenance of chromosomes 2)/SMC4异二聚体和3个起调节作用的非SMC亚基组成。目前,关于集缩素中SMC2/SMC4异二聚体的体内构象和分子作用机制仍不清楚。最近,对SMC2/SMC4异二聚体的结构解析取得许多新进展。该文在简要介绍SMC蛋白的基本结构、真核生物集缩素的发现、真核生物集缩素的结构组成的基础上,对近年来SMC2/SMC4异二聚体的结构解析的研究进展作一综述,以期为相关研究提供参考。
