基于Hill动力学与Michaelis-Menten方程,建立理论模型研究发状分裂相关增强子1(Hairy and enhancer of split 1,Hes1)调控蛋白激酶B(Protein Kinase B,AKT)-鼠双微体2(Murine Double Minute2,MDM2)-抗癌基因p53(p53)-第10号染色体缺失...基于Hill动力学与Michaelis-Menten方程,建立理论模型研究发状分裂相关增强子1(Hairy and enhancer of split 1,Hes1)调控蛋白激酶B(Protein Kinase B,AKT)-鼠双微体2(Murine Double Minute2,MDM2)-抗癌基因p53(p53)-第10号染色体缺失的磷酸酶及张力蛋白同源的基因(Phosphatase and tensin homolog deleted on chromosome ten,PTEN)通路的一种物理机制.研究发现,Hes1通过与PTEN结合抑制PTEN表达,并调控AKT信号.表明了Hes1蛋白的合成,以及Hes1与PTEN相互作用调控AKT-MDM2-p53-PTEN通路信号,将会有效地控制细胞结果.Hes1作为AKT-MDM2-p53-PTEN信号通路中上游调节的重要因素,还可以在一定程度上通过影响p53蛋白功能,改变p53对肿瘤的抑制性.理论结果可用于预测Notch通路信号异常诱导的致癌性,并进一步揭示了Notch信号通路影响细胞AKT-MDM2-p53-PTEN通路的激活机制.展开更多
Nowadays,radiation engineering is a promising direction in the creation of semiconductor devices.The proton irradiation is used to controllably change the optical,electrical,recombination,mechanical and structural pro...Nowadays,radiation engineering is a promising direction in the creation of semiconductor devices.The proton irradiation is used to controllably change the optical,electrical,recombination,mechanical and structural properties of the semiconductors.Low-energy protons make it possible to purposefully change material properties near the surface where the n^(+)-p junction is located.In this paper,the impact of low-energy protons on the electro physical parameters of n+-p-p+silicon photoelectric converters(SPC)is analyzed.The current-voltage characteristics and switching time of these SPCs are measured.The switching time is determined using rectangular bipolar voltage pulses with an amplitude of 10 mV,a frequency of 200 kHz,or a frequency of 1 MHz.A theoretical and experimental analysis of the obtained results is performed.The comparison of experimental data with the results of calculations shows that protons with an energy of 180 keV and a dose of 10×15 cm^(-2) create two regions in the space charge region of the n^(+)-p junction with different switching times of 4.2×10^(-7) s and 5.5×10^(-8) s.SPC frequency characteristics have been improved by reducing the effective lifetime by 5-10 times.This effect can be used to create high-speed photodiodes with an operating modulation frequency of 18 MHz.展开更多
文摘目的 基于c-Jun氨基末端激酶(JNK)-p62/螯合体(SQSTM1)信号通路探讨糖肾煎对2型糖尿病肾病(DN)大鼠足细胞的保护作用。方法 SD大鼠随机分成正常组、DN组、糖肾煎低、中、高[生药5、10、20 g/(kg·d)]剂量组(糖肾煎-L、M、H组)、二甲双胍组[100 mg/(kg·d)]。除正常组外,其余各组通过喂养高脂高糖饲料和腹腔注射链脲佐菌素(STZ)进行DN模型构建。药物干预结束后,检测大鼠血生化指标空腹血糖(FBG)、负荷后2 h血糖(P2 h BG)、血肌酐(SCr)、血尿素氮(BUN)水平;苏木素-伊红(HE)、六胺银(PASM)染色观察肾组织病理学变化;透射电镜(TEM)观察肾小球基底膜损伤和足细胞变化情况;Western印迹检测肾组织中微管相关蛋白1A/1B-轻链(LC)3、p-JNK、JNK、p62/SQSTM1、肾病蛋白(Nephrin)蛋白表达。结果 与正常组比较,DN组FBG、P2 h BG、SCr、BUN水平及p62/SQSTM1蛋白表达明显升高,LC3-Ⅱ、Nephrin蛋白表达和p-JNK/JNK明显降低(P<0.05);光镜下观察到肾小球缩小、管丛系膜明显扩张,并有基底膜增生增厚等现象;TEM下观察到肾小球基底膜增厚、足细胞排列紊乱、形态改变、足突融合等现象。与DN组比较,糖肾煎-L、M、H组和二甲双胍组FBG、P2 h BG、SCr、BUN水平及p62/SQSTM1蛋白表达明显降低,LC3-Ⅱ、Nephrin蛋白表达和p-JNK/JNK明显升高(P<0.05);并且肾小球基底膜增厚、足细胞足突融合等情况均获得一定程度减轻。结论 糖肾煎对2型DN大鼠足细胞具有一定保护作用,可能是通过调控JNK-p62/SQSTM1信号通路,提高足细胞自噬,从而起到肾脏保护功效。
文摘基于Hill动力学与Michaelis-Menten方程,建立理论模型研究发状分裂相关增强子1(Hairy and enhancer of split 1,Hes1)调控蛋白激酶B(Protein Kinase B,AKT)-鼠双微体2(Murine Double Minute2,MDM2)-抗癌基因p53(p53)-第10号染色体缺失的磷酸酶及张力蛋白同源的基因(Phosphatase and tensin homolog deleted on chromosome ten,PTEN)通路的一种物理机制.研究发现,Hes1通过与PTEN结合抑制PTEN表达,并调控AKT信号.表明了Hes1蛋白的合成,以及Hes1与PTEN相互作用调控AKT-MDM2-p53-PTEN通路信号,将会有效地控制细胞结果.Hes1作为AKT-MDM2-p53-PTEN信号通路中上游调节的重要因素,还可以在一定程度上通过影响p53蛋白功能,改变p53对肿瘤的抑制性.理论结果可用于预测Notch通路信号异常诱导的致癌性,并进一步揭示了Notch信号通路影响细胞AKT-MDM2-p53-PTEN通路的激活机制.
文摘Nowadays,radiation engineering is a promising direction in the creation of semiconductor devices.The proton irradiation is used to controllably change the optical,electrical,recombination,mechanical and structural properties of the semiconductors.Low-energy protons make it possible to purposefully change material properties near the surface where the n^(+)-p junction is located.In this paper,the impact of low-energy protons on the electro physical parameters of n+-p-p+silicon photoelectric converters(SPC)is analyzed.The current-voltage characteristics and switching time of these SPCs are measured.The switching time is determined using rectangular bipolar voltage pulses with an amplitude of 10 mV,a frequency of 200 kHz,or a frequency of 1 MHz.A theoretical and experimental analysis of the obtained results is performed.The comparison of experimental data with the results of calculations shows that protons with an energy of 180 keV and a dose of 10×15 cm^(-2) create two regions in the space charge region of the n^(+)-p junction with different switching times of 4.2×10^(-7) s and 5.5×10^(-8) s.SPC frequency characteristics have been improved by reducing the effective lifetime by 5-10 times.This effect can be used to create high-speed photodiodes with an operating modulation frequency of 18 MHz.
