目的探讨星状神经节阻滞(SGB)通过长链非编码RNA(lncRNA)牛磺酸上调基因1(TUG1)-NOD样受体热蛋白结构域相关蛋白3(NLRP3)轴在体外脑缺血再灌注模型中对炎症反应和自噬溶酶体形成的调节作用。方法培养大鼠海马神经元细胞系H19-7,并将细...目的探讨星状神经节阻滞(SGB)通过长链非编码RNA(lncRNA)牛磺酸上调基因1(TUG1)-NOD样受体热蛋白结构域相关蛋白3(NLRP3)轴在体外脑缺血再灌注模型中对炎症反应和自噬溶酶体形成的调节作用。方法培养大鼠海马神经元细胞系H19-7,并将细胞分为8组:(i)正常对照组:正常培养的神经元细胞;(ii)氧-糖剥夺/复氧(OGD/R)组:采用氧-糖剥夺/复氧法模拟脑缺血再灌注损伤;(iii)OGD/R+SGB组:OGD/R联合麻醉药0.5%布比卡因用于体外模拟SGB;(iv)OGD/R+SGB+TUG1过表达阴性对照组:OGD/R联合布比卡因并联合TUG1过表达阴性对照质粒转染细胞;(v)OGD/R+SGB+TUG1过表达组:OGD/R联合布比卡因并联合TUG1过表达质粒转染细胞;(vi)OGD/R+SGB+TUG1过表达+MCC950组:OGD/R联合布比卡因、TUG1过表达质粒转染及NLRP3抑制剂MCC950处理细胞;(vii)OGD/R+TUG1过表达组:OGD/R联合TUG1过表达质粒转染细胞;(viii)OGD/R+MCC950组:OGD/R联合NLRP3抑制剂MCC950处理细胞。进一步通过实时定量PCR(Quantitative Real Time PCR,qRTPCR)实验检测细胞中lncRNATUG1的表达;利用Western blot法检测细胞中NLRP3、微管相关蛋白1轻链3(LC3)-I、LC3-II、自噬相关基因5(Atg5)、苄氯素1(beclin1)、自噬接头蛋白(p62)、溶酶体相关膜蛋白1(LAMP1)的表达水平;利用透射电镜(TEM)检测自噬溶酶体的数量;并用酶联免疫吸附测定(ELISA)法检测细胞培养上清中白细胞介素(IL)-1β、IL-6、IL-18、肿瘤坏死因子(TNF)-α的含量。结果与正常对照组相比,OGD/R组lncRNA TUG1、NLRP3、Atg5、beclin1、p62、LAMP1的表达水平以及LC3-II/I比值均显著上调(^(均)P<0.05),自噬溶酶体数量增加(P<0.05),IL-1β、IL-6、IL-18、TNF-α的含量显著升高(^(均)P<0.05)。与OGD/R组相比,OGD/R+SGB组的上述指标均显著下调(P<0.05)。与OGD/R+SGB+TUG1过表达阴性对照组相比,OGD/R+SGB+TUG1过表达组的lncRNA TUG1、NLRP3、Atg5、beclin1、p62、LAMP1的表达水平以及LC3-II/I比值均显著上调(^(均)P<0.05),自噬溶酶体数量增加(P<0.05),IL-1β、IL-6、IL-18、TNF-α的含量显著升高(^(均)P<0.05),然而,加入NLRP3的抑制剂MCC950后,除lncRNA TUG1外其余指标均显著下调(^(均)P<0.05)。另外,与OGD/R组比,OGD/R+TUG1过表达组的上述指标进一步上调(^(均)P<0.05)。与OGD/R组比,OGD/R+MCC950组则抑制了除lncRNA TUG1外的其余指标(^(均)P<0.05)。结论星状神经节阻滞通过调节lncRNA TUG1-NLRP3轴有效减轻体外脑缺血再灌注损伤引起的炎症反应和自噬溶酶体形成,提示其可能作为治疗缺血性脑损伤的潜在策略。展开更多
In this paper, a new scheme that combines Space-Time Block-Coding (STBC) based on an Alamouti-like scheme and the Least Squares (LS) channel estimation using optimal training sequences in Cyclic-Prefix-based (CP)\Sing...In this paper, a new scheme that combines Space-Time Block-Coding (STBC) based on an Alamouti-like scheme and the Least Squares (LS) channel estimation using optimal training sequences in Cyclic-Prefix-based (CP)\Single-Carrier (SC) systems is proposed. With two transmit antennas, based on Cramer-Rao lower bound for channel estimation, it is shown that the Periodic Comple- mentary Set (PCS) is optimal over frequency-selective fading channels. Compared with the normal scheme without STBC, 3dB Mean Square Error (MSE) performance gains and fewer restrictions on the length of channel impulse response are demonstrated.展开更多
This paper considers the design of iterative receivers for space-frequencyblock-coded orthogonal frequency division multiplexing (SFBC-OFDM) systems in unknown wirelessdispersive fading channels. An iterative joint ch...This paper considers the design of iterative receivers for space-frequencyblock-coded orthogonal frequency division multiplexing (SFBC-OFDM) systems in unknown wirelessdispersive fading channels. An iterative joint channel estimation and symbol detection algorithm isderived. In the algorithm, the channel estimator performs alternately in two modes. During thetraining mode, the channel state information (CSI) is obtained by a discrete-Fourier-transform-basedchannel estimator and the noise variance and covariance matrix of the channel response is estimatedby the proposed method. In the data transmission mode, the CSI and transmitted data is obtainediteratively. In order to suppress the error propagation caused by a random error in identifyingsymbols, a simple error propagation detection criterion is proposed and an adaptive training schemeis applied to suppress the error propagation. Both theoretical analysis and simulation results showthat this algorithm gives better bit-error-rate performance and saves the overhead of OFDM systems.展开更多
文摘目的探讨星状神经节阻滞(SGB)通过长链非编码RNA(lncRNA)牛磺酸上调基因1(TUG1)-NOD样受体热蛋白结构域相关蛋白3(NLRP3)轴在体外脑缺血再灌注模型中对炎症反应和自噬溶酶体形成的调节作用。方法培养大鼠海马神经元细胞系H19-7,并将细胞分为8组:(i)正常对照组:正常培养的神经元细胞;(ii)氧-糖剥夺/复氧(OGD/R)组:采用氧-糖剥夺/复氧法模拟脑缺血再灌注损伤;(iii)OGD/R+SGB组:OGD/R联合麻醉药0.5%布比卡因用于体外模拟SGB;(iv)OGD/R+SGB+TUG1过表达阴性对照组:OGD/R联合布比卡因并联合TUG1过表达阴性对照质粒转染细胞;(v)OGD/R+SGB+TUG1过表达组:OGD/R联合布比卡因并联合TUG1过表达质粒转染细胞;(vi)OGD/R+SGB+TUG1过表达+MCC950组:OGD/R联合布比卡因、TUG1过表达质粒转染及NLRP3抑制剂MCC950处理细胞;(vii)OGD/R+TUG1过表达组:OGD/R联合TUG1过表达质粒转染细胞;(viii)OGD/R+MCC950组:OGD/R联合NLRP3抑制剂MCC950处理细胞。进一步通过实时定量PCR(Quantitative Real Time PCR,qRTPCR)实验检测细胞中lncRNATUG1的表达;利用Western blot法检测细胞中NLRP3、微管相关蛋白1轻链3(LC3)-I、LC3-II、自噬相关基因5(Atg5)、苄氯素1(beclin1)、自噬接头蛋白(p62)、溶酶体相关膜蛋白1(LAMP1)的表达水平;利用透射电镜(TEM)检测自噬溶酶体的数量;并用酶联免疫吸附测定(ELISA)法检测细胞培养上清中白细胞介素(IL)-1β、IL-6、IL-18、肿瘤坏死因子(TNF)-α的含量。结果与正常对照组相比,OGD/R组lncRNA TUG1、NLRP3、Atg5、beclin1、p62、LAMP1的表达水平以及LC3-II/I比值均显著上调(^(均)P<0.05),自噬溶酶体数量增加(P<0.05),IL-1β、IL-6、IL-18、TNF-α的含量显著升高(^(均)P<0.05)。与OGD/R组相比,OGD/R+SGB组的上述指标均显著下调(P<0.05)。与OGD/R+SGB+TUG1过表达阴性对照组相比,OGD/R+SGB+TUG1过表达组的lncRNA TUG1、NLRP3、Atg5、beclin1、p62、LAMP1的表达水平以及LC3-II/I比值均显著上调(^(均)P<0.05),自噬溶酶体数量增加(P<0.05),IL-1β、IL-6、IL-18、TNF-α的含量显著升高(^(均)P<0.05),然而,加入NLRP3的抑制剂MCC950后,除lncRNA TUG1外其余指标均显著下调(^(均)P<0.05)。另外,与OGD/R组比,OGD/R+TUG1过表达组的上述指标进一步上调(^(均)P<0.05)。与OGD/R组比,OGD/R+MCC950组则抑制了除lncRNA TUG1外的其余指标(^(均)P<0.05)。结论星状神经节阻滞通过调节lncRNA TUG1-NLRP3轴有效减轻体外脑缺血再灌注损伤引起的炎症反应和自噬溶酶体形成,提示其可能作为治疗缺血性脑损伤的潜在策略。
基金Supported by the National Natural Science Foundation of China (No.60472089, No.90604035).
文摘In this paper, a new scheme that combines Space-Time Block-Coding (STBC) based on an Alamouti-like scheme and the Least Squares (LS) channel estimation using optimal training sequences in Cyclic-Prefix-based (CP)\Single-Carrier (SC) systems is proposed. With two transmit antennas, based on Cramer-Rao lower bound for channel estimation, it is shown that the Periodic Comple- mentary Set (PCS) is optimal over frequency-selective fading channels. Compared with the normal scheme without STBC, 3dB Mean Square Error (MSE) performance gains and fewer restrictions on the length of channel impulse response are demonstrated.
文摘This paper considers the design of iterative receivers for space-frequencyblock-coded orthogonal frequency division multiplexing (SFBC-OFDM) systems in unknown wirelessdispersive fading channels. An iterative joint channel estimation and symbol detection algorithm isderived. In the algorithm, the channel estimator performs alternately in two modes. During thetraining mode, the channel state information (CSI) is obtained by a discrete-Fourier-transform-basedchannel estimator and the noise variance and covariance matrix of the channel response is estimatedby the proposed method. In the data transmission mode, the CSI and transmitted data is obtainediteratively. In order to suppress the error propagation caused by a random error in identifyingsymbols, a simple error propagation detection criterion is proposed and an adaptive training schemeis applied to suppress the error propagation. Both theoretical analysis and simulation results showthat this algorithm gives better bit-error-rate performance and saves the overhead of OFDM systems.
