Perrini Michela, Mauri Arabella, Ehret Alexander Edmund, Ochsenbein-Kölble Nicole, Zimmermann Roland, Ehrbar Martin, Mazza Edoardo
J Biomech Eng. 2015 Jun;137(6):061010. doi: 10.1115/1.4030054. Epub 2015 Apr 15.
The structural and mechanical integrity of amnion is essential to prevent preterm premature rupture (PPROM) of the fetal membrane. In this study, the mechanical response of human amnion to repeated loading and the microstructural mechanisms determining its behavior were investigated. Inflation and uniaxial cyclic tests were combined with corresponding in situ experiments in a multiphoton microscope (MPM). Fresh unfixed amnion was imaged during loading and changes in thickness and collagen orientation were quantified. Mechanical and in situ experiments revealed differences between the investigated configurations in the deformation and microstructural mechanisms. Repeated inflation induces a significant but reversible volume change and is characterized by high energy dissipation. Under uniaxial tension, volume reduction is associated with low energy, unrecoverable in-plane fiber reorientation.
羊膜的结构和机械完整性对于防止胎膜早破至关重要。在本研究中，研究了人羊膜对反复加载的力学响应以及决定其行为的微观结构机制。在多光子显微镜（MPM）中将充气和单轴循环试验与相应的原位实验相结合。在加载过程中对新鲜未固定的羊膜进行成像，并对厚度和胶原取向的变化进行量化。力学和原位实验揭示了所研究构型在变形和微观结构机制方面的差异。反复充气会引起显著但可逆的体积变化，其特征是能量耗散高。在单轴拉伸下，体积减小与低能量相关，面内纤维重新取向不可恢复。
