Stack M J, Aldrich A M, Kitching A D, Scott A C
Central Veterinary Laboratory, Addlestone, Surrey.
Res Vet Sci. 1995 Nov;59(3):247-54. doi: 10.1016/0034-5288(95)90012-8.
Samples of cervical spinal cord and four anatomical regions of the brains of 12 sheep with natural scrapie and six control sheep were examined by electron microscopy, after the tissues had been stored at 4 degrees C and -20 degrees C. The tissues were tested for the presence of scrapie-associated fibrils by a centrifugal extraction technique and by a touch-grid technique. The touch-grid technique was no better than the centrifugal extraction technique for the detection of fibrils. Structures which could have been classified as tubulofilaments were detected in touch-grid preparations without detergent treatment. With the centrifugal extraction technique there was a significant reduction of the fibril scores in some of the tissue extracts stored at -20 degrees C, but not in any of the extracts stored at 4 degrees C. There was, however, a reduction in the fibril scores when the final extracted pellets were stored at 4 degrees C. The stability of the fibrils on the test grids was unaffected by six months storage at room temperature but the clarity of their ultrastructure did deteriorate. Poor hydrophilic spread of the sample on the test grids did not have a significant effect on the fibril scores.
对12只患有自然痒病的绵羊和6只对照绵羊的颈脊髓及脑的四个解剖区域样本进行了电子显微镜检查，这些组织分别保存在4摄氏度和零下20摄氏度。通过离心提取技术和触网技术检测组织中是否存在痒病相关纤维。在检测纤维方面，触网技术并不比离心提取技术更好。在未经去污剂处理的触网制备物中检测到了可归类为微管丝的结构。采用离心提取技术时，保存在零下20摄氏度的一些组织提取物中的纤维评分显著降低，但保存在4摄氏度的提取物中均未出现这种情况。然而，当最终提取的沉淀保存在4摄氏度时，纤维评分有所降低。纤维在测试网格上的稳定性不受室温下六个月储存的影响，但其超微结构的清晰度确实有所下降。样本在测试网格上的亲水性铺展不佳对纤维评分没有显著影响。
