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Author:
Date:
2016-12-05
[Abstract] Viral pseudotyped particles (pp) are enveloped virus particles, typically derived from retroviruses or rhabdoviruses, that harbor heterologous envelope glycoproteins on their surface and a genome lacking essential genes. These synthetic viral particles are safer surrogates of native viruses and acquire the tropism and host entry pathway characteristics governed by the heterologous envelope glycoprotein used. They have proven to be very useful tools used in research with many applications, such as enabling the study of entry pathways of enveloped viruses and to generate effective gene-delivery vectors. The basis for their generation lies in the capacity of some viruses, such as murine leukemia virus (MLV), to incorporate envelope glycoproteins of other viruses into a pseudotyped virus ...
[摘要] 病毒假型颗粒（pp）是包膜病毒颗粒，通常来自逆转录病毒或弹状病毒，在其表面上携带异源性包膜糖蛋白和缺乏必需基因的基因组。这些合成的病毒颗粒是天然病毒的更安全的替代品并且获得由所使用的异源性包膜糖蛋白控制的嗜性和宿主进入途径特征。它们已被证明是用于具有许多应用的研究中非常有用的工具，例如使得能够研究包膜病毒的进入途径并产生有效的基因递送载体。它们的产生的基础在于一些病毒如鼠白血病病毒（MLV）的能力，以将其他病毒的包膜糖蛋白掺入假型病毒颗粒中。这些可以被工程化以包含报道基因例如荧光素酶，使得能够在易感细胞的假型粒子感染时定量病毒进入事件。在这里，我们详细说明使用中东呼吸综合征冠状病毒（MERS-CoV）尖峰（S）作为待并入的异源包膜糖蛋白的实例，能够产生基于MLV的假型包装颗粒的方案。我们还描述了这些颗粒如何用于感染易感细胞并通过荧光素酶测定进行定量感染性读数。
关键词：假型颗粒，鼠白血病病毒，包膜糖蛋白，冠状病毒，
[背景] ...
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Author:
Date:
2016-11-05
[Abstract] The SRB assay has been used since its development in 1990 (Skehan et al., 1990) to inexpensively conduct various screening assays to investigate cytotoxicity in cell based studies (Vichai and Kirtikara, 2006). This method relies on the property of SRB, which binds stoichiometrically to proteins under mild acidic conditions and then can be extracted using basic conditions; thus, the amount of bound dye can be used as a proxy for cell mass, which can then be extrapolated to measure cell proliferation.
The protocol can be divided into four main steps: preparation of treatment, incubation of cells with treatment of choice, cell fixation and SRB staining, and absorbance measurement. This assay is limited to manual or semiautomatic screening, and can be used in an efficient ...
[摘要] Limonium 已知有性和无融合生殖（通过种子的无性繁殖）繁殖模式。在这里，我们提出解剖协议为胚珠的发芽。使用微分干涉对比（DIC）显微镜。该协议允许更好地处理胚珠，并提供优于早期技术，特别是在较大胚珠的某些优势。这种方法还能够观察到完整胚珠中的减数分裂和胚囊发育，以及容易检测到区别性和无序性发育的事件。
[背景] 发生在胚珠发育期间，有必要细胞学检查胚珠。这项研究可以涉及显微镜观察石蜡或树脂包埋，切片材料或清除的器官。在D'Amato（1940; 1949）的先驱作品中公开了对性和无融合生殖物种中胚珠和胚囊发育的第一次细胞学研究。在这些作品中，花使用Karpechenko的方法固定，包埋在石蜡中，切片并用Heidenhain的铁苏木精染色，其染色质和染色体在细胞核中染色。使用这些方法的花芽切片可导致由于单个细胞的部分破坏结构完整性而具有差质量的制备物。更容易的选择是清除福尔马林：乙酸：乙醇固定的器官并用纯的Mayer's hemalum染色（Wallis，1957; Stelly等人，1984）。这种技术需要少得多的时间和劳动，特别是对于通常在卵巢中形成小胚珠的物种，这是 Limonium ...
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