用于冷冻电子显微镜的玻璃体切片中的切割伪像和切割过程

Cutting artefacts and cutting process in vitreous sections for cryo-electron microscopy.

作者信息

Al-Amoudi Ashraf, Studer Daniel, Dubochet Jacques

机构信息

Laboratoire d'Analyse Ultrastructurale, Bâtiment de Biologie, Université de Lausanne, CH-1015 Lausanne, Switzerland.

出版信息

J Struct Biol. 2005 Apr;150(1):109-21. doi: 10.1016/j.jsb.2005.01.003.

DOI:10.1016/j.jsb.2005.01.003

PMID:15797735

Abstract

Cryo-electron microscopy of vitreous sections (CEMOVIS) has recently been shown to provide images of biological specimens with unprecedented quality and resolution. Cutting the sections remains however the major difficulty. Here, we examine the parameters influencing the quality of the sections and analyse the resulting artefacts. They are in particular: knife marks, compression, crevasses, and chatter. We propose a model taking into account the interplay between viscous flow and fracture. We confirm that crevasses are formed on only one side of the section, and define conditions by which they can be avoided. Chatter is an effect of irregular compression due to friction of the section of the knife edge and conditions to prevent this are also explored. In absence of crevasses and chatter, the bulk of the section is compressed approximately homogeneously. Within this approximation, it is possible to correct for compression by a simple linear transformation for the bulk of the section. A research program is proposed to test and refine our understanding of the sectioning process.

摘要

最近研究表明，玻璃体切片冷冻电子显微镜技术（CEMOVIS）能够提供具有前所未有的质量和分辨率的生物样本图像。然而，切片仍然是主要难题。在此，我们研究了影响切片质量的参数，并分析了由此产生的伪像。这些伪像尤其包括：刀痕、压缩、裂缝和震颤。我们提出了一个考虑粘性流动和断裂之间相互作用的模型。我们证实裂缝仅在切片的一侧形成，并确定了可以避免裂缝的条件。震颤是由于刀刃与切片之间的摩擦导致的不规则压缩效应，我们也探索了防止这种情况的条件。在没有裂缝和震颤的情况下，切片的大部分区域被大致均匀地压缩。在这种近似情况下，可以通过对切片大部分区域进行简单的线性变换来校正压缩。我们提出了一个研究计划，以测试和完善我们对切片过程的理解。