Fukatsu R, Obara T, Baba N, Kanaya K, Garruto R, Hayashishita T, Kurokawa Y, Ueno T, Takahata N
Department of Neuropsychiatry, Sapporo Medical College, Japan.
Acta Neuropathol. 1988;75(5):519-22. doi: 10.1007/BF00687141.
The ultrastructure of neurofibrillary tangles of Alzheimer's disease was analyzed by computerized digital processing of electron micrographs. Processing of the electron micrographs consists of four steps: digitizing the electron micrograph, Fourier transformation, noise filtering and inverse Fourier transformation and Laplacian operation. In the present study, we have confirmed that neurofibrillary tangles are composed of a pair of helical filaments (PHF), which appear characteristically as an unbranched rigid structure. The periodicity of PHF is 78 nm on the diffractogram. The dimensions of PHF obtained by our analysis, although basically similar to those described earlier by other investigators using conventional techniques, more precisely defines its structural conformation. We have also demonstrated that the spatial relationship of two filaments appears symmetrical after two-way tilting of the specimen about the axis of rotation. Our observations emphasize the importance of digital image processing as an effective tool for structural analytical research in biology and medicine.
通过对电子显微镜照片进行计算机数字处理，分析了阿尔茨海默病神经原纤维缠结的超微结构。电子显微镜照片的处理包括四个步骤：将电子显微镜照片数字化、傅里叶变换、噪声滤波以及傅里叶逆变换和拉普拉斯运算。在本研究中，我们已经证实神经原纤维缠结由一对螺旋丝（PHF）组成，其特征表现为无分支的刚性结构。在衍射图上，PHF的周期为78纳米。我们分析得到的PHF尺寸，虽然基本上与其他研究人员先前使用传统技术描述的尺寸相似，但更精确地定义了其结构构象。我们还证明，在标本围绕旋转轴进行双向倾斜后，两根细丝的空间关系显得对称。我们的观察结果强调了数字图像处理作为生物学和医学结构分析研究的有效工具的重要性。
