Berberine Induces Caspase-Independent Cell Death in Colon Tumor Cells through Activation of Apoptosis-Inducing Factor

Berberine, an isoquinoline alkaloid derived from plants, is a traditional medicine for treating bacterial diarrhea and intestinal parasite infections. Although berberine has recently been shown to suppress growth of several tumor cell lines, information regarding the effect of berberine on colon tumor growth is limited. Here, we investigated the mechanisms underlying the effects of berberine on regulating the fate of colon tumor cells, specifically the mouse immorto-Min colonic epithelial (IMCE) cells carrying the Apcmin mutation, and of normal colon epithelial cells, namely young adult mouse colonic epithelium (YAMC) cells. Berberine decreased colon tumor colony formation in agar, and induced cell death and LDH release in a time- and concentration-dependent manner in IMCE cells. In contrast, YAMC cells were not sensitive to berberine-induced cell death. Berberine did not stimulate caspase activation, and PARP cleavage and berberine-induced cell death were not affected by a caspase inhibitor in IMCE cells. Rather, berberine stimulated a caspase-independent cell death mediator, apoptosis-inducing factor (AIF) release from mitochondria and nuclear translocation in a ROS production-dependent manner. Amelioration of berberine-stimulated ROS production or suppression of AIF expression blocked berberine-induced cell death and LDH release in IMCE cells. Furthermore, two targets of ROS production in cells, cathepsin B release from lysosomes and PARP activation were induced by berberine. Blockage of either of these pathways decreased berberine-induced AIF activation and cell death in IMCE cells. Thus, berberine-stimulated ROS production leads to cathepsin B release and PARP activation-dependent AIF activation, resulting in caspase-independent cell death in colon tumor cells. Notably, normal colon epithelial cells are less susceptible to berberine-induced cell death, which suggests the specific inhibitory effects of berberine on colon tumor cell growth

The relationship between depressive symptoms and reduced pleasure forecasting: the mediating role of low pleasure belief

摘要：情绪预期是指个体对于未来事件引起的情绪反应的预测。前人研究发现，抑郁症状更多的个体比抑郁症状更少的个体预期更少的愉快情绪，然而其背后的工作机制尚未清楚。低愉快信念是指个体认为某些特定的活动不愉快，或个体认为自己总体上不能体验到愉快情绪。低愉快信念可能影响情绪预期的加工，也可能与抑郁症状存在联系，因此低愉快信念可能是抑郁症状与情绪预期缺损的中介因素。本研究将探讨低愉快信念与抑郁症状的关系，并进一步探讨低愉快信念在抑郁症状与降低的愉快情绪预期中的中介作用。本研究共收集1427份有效问卷，其中男生411人(22.88&plusmn;2.50岁)，女生1016人(21.95&plusmn;2.25岁)。研究采用贝克抑郁量表对抑郁症状进行测量；采用愉快信念量表测量低愉快信念；采用时间性愉快体验量表、期待性与即时性人际间愉快体验量表中的期待性条目测量对愉快情绪的预期。本研究采用偏相关分析探讨低愉快信念与抑郁症状的关系，并采用结构方程模型探讨低愉快信念的中介作用。研究结果发现，在控制了年龄与性别的条件下，低愉快信念与抑郁症状之间存在显著的正相关（r=0.36, p&lt;0.001）。此外，观测数据与假设的中介模型吻合度良好(RMSEA=0.007; CFI=1; TLI=0.999; &chi;2=1.07; p=0.30)，低愉快信念的中介作用显著(&beta;=-0.14, 90% CI=-0.173 to &ndash; 0.111, p&lt;0.001)。研究结果提示了抑郁症状个体可能有低愉快信念，并且低愉快信念可能是造成抑郁症状人群减少的愉快情绪预期的原因之一。</p

生物多样性近地面遥感监测:应用现状与前景展望

近年来中国生物多样性监测与研究网络(Sino BON)建设得到了快速发展,为我国生物多样性长期监测和研究提供了良好的平台条件。其中,以激光雷达技术为核心的近地面遥感平台,作为Sino BON综合监测与管理中心的重要组成部分,已研发形成了较为成熟的软、硬件技术体系,可以提供林下地形建模,林分高度、林分表面结构,林窗或内部分界线,郁闭度动态,植被群落划分、群落内部精细空间结构,单木高度与胸径,冠层形态、周长和盖度,物种识别,亚米级三维景观图等数字产品,从而能够为国家相关部门和研究单位开展多种时空尺度的生物多样性监测、评价和保护工作提供精准、高效的技术支持。本文首先介绍了遥感技术在生物多样性研究中的应用发展历史及最新趋势。然后在生物多样性遥感监测直接和间接两种方法研究进展基础之上,总结了从遥感数据中可提取的重要生物多样性指标,以及选择不同类型遥感数据源时需要考虑的时空尺度信息。在详细阐述NEON、CEOS、GEO BON等国际合作组织推动遥感技术开展生物多样性监测的过程中指明:以无人机为代表的近地面遥感平台具有机动灵活、高效低廉和高分辨率的特点,可在卫星平台、载人航空平台和地面常规调查平台之间架构起生物多样性信息尺度推绎不可或缺的中间桥梁,将是未来生物多样性监测的一个重要手段。最后,文章指出:Sino BON近地面遥感平台的逐步建设完善将为我国生物多样性监测提供全方位的立体定量化信息,在促进我国生物多样性监测网络向跨尺度等级动态系统监测、多源信息集成、智能决策与服务的平台方向发展意义重大

HIRFL-CSR超高真空系统

中国科学院近代物理研究所承担的国家“九·五”重大科学工程项目兰州重离子加速器冷却储存环(HIRFL- CSR)目前正处在建设阶段。为减少真空系统中残余气体分子对粒子束造成的损失 ,要求系统平均真空度达到 6× 10 - 9Pa。在研制和建造过程中 ,我们做了大量的工作以获得所要求的真空度。本文将介绍其中样机的研制 ,超高真空实验室的建立和各项实验工作 ,大型真空处理设备的建造 ,真空烘烤系统研制等。同时对目前的工程进展也做了简要介

真空炉高温除气工艺对降低不锈钢出气率的作用

真空炉高温除气工艺可以大大降低不锈钢出气率。通过应用实例,给出了真空炉高温除气和现场烘烤除气及二者结合除气的结果,分析了真空炉高温除气的有利因素,证明采用该工艺对于降低不锈钢出气率,从而获得超高真空具有显著的效果

不锈钢材料在真空炉高温除气后的出气性能比较

根据兰州重离子加速器冷却储存环真空系统(HIRFL-CSR)材料处理工艺要求,需要对所有不锈钢元件进行真空炉高温除气处理以降低材料出气率。本文通过一组实验测试数据,介绍了采用除气处理工艺和未经除气处理的不锈钢材料出气情况对比,证明采用真空炉除气处理工艺可以使材料内部的H2、CO、CO2等组分大幅度减少,从而获得较低的材料出气率

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies