朱砂叶螨羧酸脂酶最优测试条件的选择

应用二次回归通用旋转组合设计,对朱砂叶螨离体羧酸酯酶测试过程中所需缓冲液pH值、恒温时间、反应温度及底物浓度,设立4因子5水平试验,在考虑4个因子主效应和互作效应的情况下,筛选测试羧酸酯酶的最优条件组合。     

无花果果皮中花青素的提取工艺的建立

本研究使用单因素方法考察了无花果(Ficus carica L.)果皮中花青素的最佳提取条件,并考察了7种参数对花青素提取率的影响。参数设置如下:溶剂性质(水,甲醇,乙醇和丙酮)、提取次数(1~3次)、固液比(1/50,1/100,1/150和1/200)、提取时间(60 min,120 min,180 min和240 min)、甲醇浓度(0,20%,40%,60%,80%和100%)、酸类型(盐酸,乙酸,柠檬酸和酒石酸)和酸浓度(0,1%,2%,5%和10%)。使用pH-示差法测量无花果果皮中单体花色素的含量。研究显示,无花果果皮中花青素的最佳提取条件为:溶剂为甲醇溶剂,提取次数为2次,固液比为1/100,提取时间为180 min,甲醇浓度为80%,酸类型为柠檬酸,柠檬酸浓度为5%。该最佳提取条件下的花青素的提取率达到最高(345.62 mg/100g DS)。     

凝胶电泳微流控芯片提取外泌体及对人血浆外泌体中miRNA-21的测定

为了开发一种用于人体血浆中外泌体的高效快速提取和分离的新型微流控芯片,文中收集健康人体外周血液样本,自主设计并制备基于纳米多孔薄膜和琼脂糖凝胶电泳的微流芯片。提取的外泌体使用透射电镜、Nanosight和Western blotting等技术进行表征,鉴定并分析其形态、浓度和粒径分布。同时将超速离心法和微流芯片所提取的外泌体进行粒径和浓度的分析比较,探讨两种方法各自的提取效率。最后,利用RT-PCR技术分析外泌体中miRNA-21的相对表达量。凝胶电泳微流芯片可在1 h内快速的从血浆中高效率地提取出纯度高、大小完整、尺寸分布在30–200 nm之间的外泌体,满足后续下游分析的要求。通过与现有最普遍的超速离心法进行对比分析,当血浆样本量小于100μL时,凝胶电泳微流芯片提取外泌体的效率为超速离心法的3.80倍。凝胶电泳微流芯片提取外泌体的优化参数是:电场电压:100 V;琼脂糖凝胶浓度:1.0%;注射泵流速:0.1 mL/h。凝胶电泳微流芯片可快速高效地提取出外泌体,对外泌体与癌症生物标记物的相关研究具有潜在的巨大优势,也为基于外泌体的即时诊断技术提供了可能。     

间作植物和茬口对连作党参生长和品质产量的影响

选择两种茬口(轮作茬、连作茬)和6种植物材料(党参、大蒜、玉米、黄芪、苦参、向日葵),组成党参单作和间作6种种植模式,设置茬口和间作模式两因素田间随机区组试验,通过监测不同生长时期党参的生长指标(蔓长、主根长、主根直径、地下部分鲜干重)、根部产量及品质指标(根部多糖含量、炔苷含量、醇溶性浸出物含量和灰分含量)的变化衡量不同茬口和间作植物对党参连作障碍的缓解效应。结果表明：(1)轮作茬口下党参单作及各间作处理对党参生长、品质和产量的改善效果都较连作茬口下明显,且两茬口下各间作处理的改善效果都较党参单作明显。(2)与向日葵、大蒜和玉米间作处理对两茬口党参的主根长、主根直径、地下部分鲜干重的提升效果比党参单作和其余间作处理(与黄芪、苦参间作)更显著。(3)大蒜和向日葵间作处理能够显著提高两茬口党参根部产量,尤其大蒜表现最优,与其间作的轮作茬和连作茬党参分别较各自对照增产49.92%和22.55%。(4)与大蒜间作能有效提升两茬口党参根部多糖含量、炔苷含量和醇溶性浸出物的含量,党参单作和其余间作处理对两茬口连作党参的品质提升效果不及大蒜间作处理理想。研究发现,从党参长势及根部产量和品质综合分析,两茬口下党参与大蒜间作最有利于党参植株生长,能有效缓解党参连作障碍,并显著提高其药用部位的产量和品质,且轮作茬口下的提高效应更明显。     

Absolute Quantification of E1, Ubiquitin-Like Proteins and Nedd8–MLN4924 Adduct by Mass Spectrometry

Ubiquitin (Ub) and ubiquitin-like (Ubl) proteins regulate a variety of important cellular processes by forming covalent conjugates with target proteins or lipids. Ubl conjugation is catalyzed by a cascade of proteins including activating enzymes (E1), conjugating enzymes (E2), and in many cases ligation enzymes (E3). The discovery of MLN4924 (Brownell et al., Mol Cell 37: 102–111, 1), an investigational small molecule that is a mechanism-based inhibitor of NEDD8-activating enzyme (NAE), reveals a promising strategy of targeting E1/Ubl pathway for therapeutic purposes. In order to better understand, the biochemical dynamics of Ubl conjugation in cells and tissues, we have developed a mass spectrometry-based method to quantify E1 and Ubls using isotope-labeled proteins as internal standards. Furthermore, we have used the described method to quantify levels of the covalent Nedd8-inhibitor adduct formed in MLN4924 treated cells and tissues. The Nedd8–MLN4924 adduct is a tight-binding inhibitor of NAE, and its cellular concentration represents an indirect pharmacodynamic readout of NAE/Nedd8 pathway inhibition.     

Bidirectional Transfer between Metaphorical Related Domains in Implicit Learning of Form-Meaning Connections

People can implicitly learn a connection between linguistic forms and meanings, for example between specific determiners (e.g. this, that…) and the type of nouns to which they apply. Li et al (2013) recently found that transfer of form-meaning connections from a concrete domain (height) to an abstract domain (power) was achieved in a metaphor-consistent way without awareness, showing that unconscious knowledge can be abstract and flexibly deployed. The current study aims to determine whether people transfer knowledge of form-meaning connections not only from a concrete domain to an abstract one, but also vice versa, consistent with metaphor representation being bi-directional. With a similar paradigm as used by Li et al, participants learnt form- meaning connections of different domains (concrete vs. abstract) and then were tested on two kinds of generalizations (same and different domain generalization). As predicted, transfer of form-meaning connections occurred bidirectionally when structural knowledge was unconscious. Moreover, the present study also revealed that more transfer occurred between metaphorically related domains when judgment knowledge was conscious (intuition) rather than unconscious (guess). Conscious and unconscious judgment knowledge may have different functional properties.     

基因敲除技术及其在研究线粒体动力学与胰岛素抵抗关系中的应用进展

线粒体动力学即线粒体融合和分裂保持动态平衡的过程,该过程由融合/分裂相关蛋白精确调控完成,对于线粒体代谢、质量和功能有着重要的生理意义,而这些蛋白发生异常可引发线粒体动力学失衡,进而引起线粒体功能障碍并引发各种疾病状态。文中围绕基因敲除技术,详细阐述了编码融合/分裂相关蛋白的基因敲除鼠在胰岛素抵抗研究工作中的作用及应用进展,以期为今后研究线粒体动力学失衡致胰岛素抵抗的信号转导机制奠定基础。