背景:正畸牙移动骨重塑的机械力信号转导通路及其调控机制是正畸生物力学和生物学研究的热点。目前正畸牙移动过程中张力侧牙周膜细胞对机械刺激反应的复杂分子信号网络机制尚不太明确。目的:探究正畸牙移动过程中张应力作用下高迁移率...背景:正畸牙移动骨重塑的机械力信号转导通路及其调控机制是正畸生物力学和生物学研究的热点。目前正畸牙移动过程中张力侧牙周膜细胞对机械刺激反应的复杂分子信号网络机制尚不太明确。目的:探究正畸牙移动过程中张应力作用下高迁移率族蛋白B1(high mobility group protein 1,HMGB1)和ERK1/2通路对人牙周膜细胞自噬的影响。方法:选取第3-5代生长状态良好的人牙周膜细胞,施加周期性张应力,利用免疫荧光观察HMGB1在细胞中的分布情况,RT-qPCR及Westernblot检测自噬相关蛋白LC3-Ⅱ、Beclin-1和HMGB1的表达水平,完成张应力加载后分别提取胞核蛋白和胞浆蛋白,Westernblot分别检测胞核及胞浆中HMGB1蛋白水平。为探究HMGB1通过何种机制参与调控细胞自噬,使用丙酮酸乙酯(HMGB1胞浆抑制剂)进行细胞处理,通过免疫荧光、RT-qPCR和Western blot检测细胞自噬水平。最后,选用PD98059抑制ERK1/2通路,通过RT-qPCR以及Western blot检测自噬水平变化,探讨HMGB1通过ERK1/2通路调控自噬的机制。结果与结论:(1)通过体外张应力加载,诱导了人牙周膜细胞内自噬水平升高,HMGB1的表达增加,同时HMGB1发生了由胞核到胞质的转位;(2)人牙周膜细胞通过HMGB1核质转位机制参与张应力作用下自噬的调控;(3)使用ERK1/2通路抑制剂PD98059显著抑制了张应力作用下HMGB1引起的细胞自噬;(4)结果表明,张应力作用下HMGB1从细胞核转移到细胞质,并通过ERK1/2途径调节自噬,维持人牙周膜细胞的稳态和牙周动态平衡。展开更多
The purpose of present work is to examine the financial problem of finding the universal reservation prices of a European call option written on exchange rate when there is proportional transaction costs of trading fo...The purpose of present work is to examine the financial problem of finding the universal reservation prices of a European call option written on exchange rate when there is proportional transaction costs of trading foreign currency in the market. An approach is suggested to compute the reservation bid-ask price of foreign currency call option based on maximizing the investor＇s expected utility. Option prices are determined from the investor＇s basic portfolio selection problem, without the need to solve a more complex optimization problem involving the insertion of the option payoffs into the terminal value function. Option prices are computed numerically in a Markov chain approximation for the case of exponential utility. Numerical results show that the option price bounds are almost independent of the alternative risk aversion parameter, but the bounds of NT region becomes narrower and the range of values of the initial holding for which the fair price lies within the bid-ask spread is shifted to a lower value when the risk aversion parameter increases.展开更多
文摘背景:正畸牙移动骨重塑的机械力信号转导通路及其调控机制是正畸生物力学和生物学研究的热点。目前正畸牙移动过程中张力侧牙周膜细胞对机械刺激反应的复杂分子信号网络机制尚不太明确。目的:探究正畸牙移动过程中张应力作用下高迁移率族蛋白B1(high mobility group protein 1,HMGB1)和ERK1/2通路对人牙周膜细胞自噬的影响。方法:选取第3-5代生长状态良好的人牙周膜细胞,施加周期性张应力,利用免疫荧光观察HMGB1在细胞中的分布情况,RT-qPCR及Westernblot检测自噬相关蛋白LC3-Ⅱ、Beclin-1和HMGB1的表达水平,完成张应力加载后分别提取胞核蛋白和胞浆蛋白,Westernblot分别检测胞核及胞浆中HMGB1蛋白水平。为探究HMGB1通过何种机制参与调控细胞自噬,使用丙酮酸乙酯(HMGB1胞浆抑制剂)进行细胞处理,通过免疫荧光、RT-qPCR和Western blot检测细胞自噬水平。最后,选用PD98059抑制ERK1/2通路,通过RT-qPCR以及Western blot检测自噬水平变化,探讨HMGB1通过ERK1/2通路调控自噬的机制。结果与结论:(1)通过体外张应力加载,诱导了人牙周膜细胞内自噬水平升高,HMGB1的表达增加,同时HMGB1发生了由胞核到胞质的转位;(2)人牙周膜细胞通过HMGB1核质转位机制参与张应力作用下自噬的调控;(3)使用ERK1/2通路抑制剂PD98059显著抑制了张应力作用下HMGB1引起的细胞自噬;(4)结果表明,张应力作用下HMGB1从细胞核转移到细胞质,并通过ERK1/2途径调节自噬,维持人牙周膜细胞的稳态和牙周动态平衡。
基金Supported by the Natural Science Foundation of Zhejiang Province (Y604137) the Altitude College Natural Science Foundation of JiangSu Province (KY205017).
文摘The purpose of present work is to examine the financial problem of finding the universal reservation prices of a European call option written on exchange rate when there is proportional transaction costs of trading foreign currency in the market. An approach is suggested to compute the reservation bid-ask price of foreign currency call option based on maximizing the investor＇s expected utility. Option prices are determined from the investor＇s basic portfolio selection problem, without the need to solve a more complex optimization problem involving the insertion of the option payoffs into the terminal value function. Option prices are computed numerically in a Markov chain approximation for the case of exponential utility. Numerical results show that the option price bounds are almost independent of the alternative risk aversion parameter, but the bounds of NT region becomes narrower and the range of values of the initial holding for which the fair price lies within the bid-ask spread is shifted to a lower value when the risk aversion parameter increases.
