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在生物聚合物矩阵中,局部反应和新出现的非线性弹性长度尺度
Haiqian Yang1, Estelle Berthier2, Chenghai Li3
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
概括
细胞通过产生力,在局部地使细胞外基质 (ECM) 变硬. 一个非线性长度尺度出现,取决于力大小,可以在活细胞周围观察到.
科学领域:
- 生物物理学的生物物理.
- 材料科学 材料科学 材料科学
- 细胞生物学 细胞生物学
背景情况:
- 非线性硬化是细胞外基质 (ECM) 中生物聚合物的关键性质.
- 像纤维细胞和癌细胞这样的细胞对ECM施加力量,导致局部硬化.
- 这种细胞力产生通常被建模为断力,因为它们的状形状.
研究的目的:
- 研究ECM对局部断力的非线性力位移反应.
- 开发一个理论框架,解释局部力量如何诱导矩阵刚性.
- 观察和描述活细胞周围出现的非线性长度尺度.
主要方法:
- 使用光学子来应用和测量ECM组件上的局部断力.
- 开发一个有效探头缩放参数来建模强力诱导的硬化.
- 观察活细胞周围的非线性长度尺度,并通过改变矩阵度或细胞收缩性来扰乱它.
主要成果:
- 对局部化的断力量表现出非线性力位移反应.
- 提出了一个非线性长度尺度 (R*) 标志着硬化的区域,随着力大小的增加而增加.
- 展示了在活细胞周围观察这种非线性长度尺度的观测,该尺度对矩阵特性和细胞收缩性敏感.
结论:
- 局部化的细胞力量导致细胞外基质的非线性硬化.
- 一个出现的非线性长度尺度 (R*) 量化了这种硬效应.
- 这种现象可以在体内观察到,并且可以通过细胞和矩阵环境来调节.
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