Characterization of the three-dimensional kinematic behavior of axons in central nervous system white matter
Characterization of the three-dimensional kinematic behavior of axons in central nervous system white matter
复制标题
中枢神经系统白质轴突三维运动行为的表征
DOI：
--
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发表时间：
2015
影响因子：
3.5
通讯作者：
D. Shreiber
中科院分区：
文献类型：
--
作者：
Sagar Singh;A. Pelegri;D. Shreiber
大脑和脊髓白质轴突的创伤性损伤主要是通过拉伸引起的。受伤期间，组织水平上经历的应力和应变会转移到微观轴突。必须更好地理解这种转移是如何发生的，以及决定这种转移的主要成分，以开发更准确的多尺度损伤模型。先前的研究已经描述了二维 (2-D) 中的轴突弯曲和运动行为，其中轴突被建模为表现出非仿射（离散）、仿射（类复合）或切换行为。在这项研究中，我们描述了轴突弯曲度并模拟了 3 维 (3-D) 的轴突运动行为。不同发育阶段的胚胎鸡脊髓被切除并拉伸。然后将绳索固定、横向切片、染色并成像。使用定制的 MATLAB 脚本从共焦图像测量 3-D 轴突弯曲度。 Bain 等人先前描述的二维运动学模型。 (J Biomech Eng 125(6):798, 2003) 对 3-D 案例进行了扩展、重新推导和验证。结果表明，3-D 弯曲度随着拉伸而减小，与 2-D 研究中观察到的发育变化表现出相似的趋势。运动学参数也显示出类似的总体趋势。随着伸展和发育的增加，轴突表现出更多的仿射行为。与 2-D 结果相比，预计 3-D 轴突群体中较小比例的人会遵循纯非仿射行为。本文提出的数据和运动学模型可以合并到多尺度 CNS 损伤模型中，这可以提高模型的准确性并提高识别轴突损伤阈值的潜力。
Traumatic injury to axons in white matter of the brain and spinal cord occurs primarily via tensile stretch. During injury, the stress and strain experienced at the tissue level is transferred to the microscopic axons. How this transfer occurs, and the primary constituents dictating this transfer must be better understood to develop more accurate multi-scale models of injury. Previous studies have characterized axon tortuosity and kinematic behavior in 2-dimensions (2-D), where axons have been modeled to exhibit non-affine (discrete), affine (composite-like), or switching behavior. In this study, we characterize axon tortuosity and model axon kinematic behavior in 3-dimensions (3-D). Embryonic chick spinal cords at different development stages were excised and stretched. Cords were then fixed, transversely sectioned, stained, and imaged. 3-D axon tortuosity was measured from confocal images using a custom-built MATLAB script. 2-D kinematic models previously described in Bain et al. (J Biomech Eng 125(6):798, 2003) were extended, re-derived, and validated for the 3-D case. Results showed that 3-D tortuosity decreased with stretch, exhibiting similar trends with changes in development as observed in the 2-D studies. Kinematic parameters also displayed similar general trends. Axons demonstrated more affine behavior with increasing stretch and development. In comparison with 2-D results, a smaller percentage of the populations of 3-D axons were predicted to follow pure non-affine behavior. The data and kinematic models presented herein can be incorporated into multi-scale CNS injury models, which can advance the accuracy of the models and improve the potential to identify axonal injury thresholds.
DOI：
10.1115/1.1324667
发表时间：
2000-12-01
影响因子：
1.7
作者：
Bain, AC;Meaney, DF
通讯作者：
Meaney, DF