染色质免疫共沉淀测序(chromatin immunoprecipitation followed by sequencing,ChIP-seq)是研究目的蛋白与DNA相互作用的重要方法,被广泛应用于转录因子、组蛋白修饰等分布与功能的研究。研究人员通过对细胞分离、染色质片段化以及测...染色质免疫共沉淀测序(chromatin immunoprecipitation followed by sequencing,ChIP-seq)是研究目的蛋白与DNA相互作用的重要方法,被广泛应用于转录因子、组蛋白修饰等分布与功能的研究。研究人员通过对细胞分离、染色质片段化以及测序文库构建等关键步骤不断优化,使ChIP-seq适合少量细胞的分析。近年来发展迅速的CUT&RUN(cleavage under targets and release using nuclease)、CUT&Tag(cleavage under targets and tagmentation)技术,利用特异性抗体使酶“靶向”结合目标蛋白,通过MNase酶切或Tn5转座酶切割染色质,简化了实验操作流程。本文介绍了ChIP-seq的原理及其数据分析方法,比较ChIP-seq优化方法和衍生技术。总结了在植物生长发育过程中,转录因子和组蛋白修饰在生物钟调控、激素信号转导、光信号途径、胁迫响应等方面研究与染色质免疫共沉淀测序技术的应用。展开更多
Background Intravascular microbubble-enhanced acoustic cavitation is capable of disrupting the vascular walls of capillaries and small vessels. This study was designed to investigate the impact of microbubble-enhanced...Background Intravascular microbubble-enhanced acoustic cavitation is capable of disrupting the vascular walls of capillaries and small vessels. This study was designed to investigate the impact of microbubble-enhanced, pulsed and focused ultrasound （MEUS） on the blood perfusion of subcutaneous VX2 tumors in rabbits. Methods Subcutaneous VX2 cancers in twenty New Zealand rabbits were treated by combining high-pressure amplitude, pulsed and focused therapeutic ultrasound （TUS） and intravenous microbubble injections. The TUS transducer was operated with a peak negative pressure of 4.6 MPa and a duty cycle of 0.41%. Controls were subcutaneous VX2 cancers treated with TUS or microbubbles only. Contrast-enhanced ultrasound （CEUS） and intravenous Evans Blue （EB） perfusion were performed to assess the tumor circulation. The tumor microvascular disruption was assessed by histological examination. Results CEUS showed that the tumor circulation almost vanished after MEUS treatment. The average peak grayscale value （GSV） of tumor CEUS dropped significantly from 84.1±22.4 to 15.8±10.8 in the MEUS-treated tumors but no significant GSV changes were found in tumors in the two control groups. The mean tumor EB content of the MEUS-treated tumors was significantly lower than that of the controls. Histological examination found scattered tumor microvascular disruption with intercellular edema after MEUS treatment. Conclusion The tumor circulation of VX2 cancers can be arrested or significantly reduced by MEUS due to microvascular disruption. Chin M~.cl ,I 2014：127 （14）： 2605-2611展开更多
文摘染色质免疫共沉淀测序(chromatin immunoprecipitation followed by sequencing,ChIP-seq)是研究目的蛋白与DNA相互作用的重要方法,被广泛应用于转录因子、组蛋白修饰等分布与功能的研究。研究人员通过对细胞分离、染色质片段化以及测序文库构建等关键步骤不断优化,使ChIP-seq适合少量细胞的分析。近年来发展迅速的CUT&RUN(cleavage under targets and release using nuclease)、CUT&Tag(cleavage under targets and tagmentation)技术,利用特异性抗体使酶“靶向”结合目标蛋白,通过MNase酶切或Tn5转座酶切割染色质,简化了实验操作流程。本文介绍了ChIP-seq的原理及其数据分析方法,比较ChIP-seq优化方法和衍生技术。总结了在植物生长发育过程中,转录因子和组蛋白修饰在生物钟调控、激素信号转导、光信号途径、胁迫响应等方面研究与染色质免疫共沉淀测序技术的应用。
文摘Background Intravascular microbubble-enhanced acoustic cavitation is capable of disrupting the vascular walls of capillaries and small vessels. This study was designed to investigate the impact of microbubble-enhanced, pulsed and focused ultrasound （MEUS） on the blood perfusion of subcutaneous VX2 tumors in rabbits. Methods Subcutaneous VX2 cancers in twenty New Zealand rabbits were treated by combining high-pressure amplitude, pulsed and focused therapeutic ultrasound （TUS） and intravenous microbubble injections. The TUS transducer was operated with a peak negative pressure of 4.6 MPa and a duty cycle of 0.41%. Controls were subcutaneous VX2 cancers treated with TUS or microbubbles only. Contrast-enhanced ultrasound （CEUS） and intravenous Evans Blue （EB） perfusion were performed to assess the tumor circulation. The tumor microvascular disruption was assessed by histological examination. Results CEUS showed that the tumor circulation almost vanished after MEUS treatment. The average peak grayscale value （GSV） of tumor CEUS dropped significantly from 84.1±22.4 to 15.8±10.8 in the MEUS-treated tumors but no significant GSV changes were found in tumors in the two control groups. The mean tumor EB content of the MEUS-treated tumors was significantly lower than that of the controls. Histological examination found scattered tumor microvascular disruption with intercellular edema after MEUS treatment. Conclusion The tumor circulation of VX2 cancers can be arrested or significantly reduced by MEUS due to microvascular disruption. Chin M~.cl ,I 2014：127 （14）： 2605-2611
