生物软组织力-化-生耦合生长与失稳的理论和实验研究

Soft biological tissues and organs manifest various morphologies which may undergo observable transitions under physiological and pathological conditions. Understanding the relationship among the chemical components, mechanical properties, geometrical shapes, and biological functions of soft tissues and exploring the coupling among mechanics, chemistry, and biology constitute a multidisciplinary research field, which also becomes an important issue within current biomechanics. This study will focus on growth, which is regarded as one of the most fundamental features of living tissues. A theoretical model that accounts for the mechano-chemical coupled finite deformation induced by growth will be established. Some representative tissues including intestine, stomach, and brain will be taken as example to examine the instabilities and the subsequent morphological evolution induced by non-uniform growth or constraint growth. Based on the proposed theory, numerical method will be developed to capture the characteristics of multiple bifurcations and multiple morphological transitions. We will design biological and chemical experiments to study the mechano-chemo-biological coupled morphogenesis during the early development of tissues. In vitro experiments including indentation, aspiration techniques, and traditional tensile tests will be performed to measure the mechanical properties of soft tissues. The residual deformation induced by growth will be evaluated by dissection. A series of phantom experiments will be carried out to simulate instabilities of some representative soft tissues. Furthermore, we will explore the potential applications of our results in the diagnosis and treat of some related diseases.

生物软组织和器官呈现出迥异的几何形态，该形态在生理和病理条件下可以发生显著变化。深入研究软组织的化学成分、力学性质、几何形态、生物功能这四者之间的有机联系，探究力学、化学、生物学等因素之间的耦合效应，是一个多学科交叉领域，也是现代生物力学关注的一个重要课题。本项目将从软组织最基本的生长特征出发，建立考虑力、化学耦合的软组织生长大变形的理论模型，以几种典型生物组织如肠道、胃、脑为例，分析软组织非均匀生长、受限生长的失稳与后继形貌演化；发展数值方法模拟三维、曲面构型中软组织生长所致多次分岔、多重形貌转化的特征；设计生化实验观测软组织早期发育过程中的力-化-生耦合的形貌演化特征；开展压痕、吸管、拉伸结合的体外实验测量软组织力学性质，通过解剖法观测软组织生长导致的残余应力，并设计相关仿体实验模拟典型软组织失稳。进而探索研究结果在某些典型疾病临床诊疗上的潜在应用。

生物软组织和器官呈现出迥异的几何形态，该形态在生理和病理条件下可以发生显著变化。深入研究软组织的化学成分、力学性质、几何形态、生物功能这四者之间的有机联系，探究力学、化学、生物学等因素之间的耦合效应，是一个多学科交叉领域，也是现代生物力学关注的一个重要课题。本项目从软组织最基本的生长特征出发，建立了考虑力、化学耦合的软组织生长大变形的理论模型，以实体肿瘤、上皮组织为例，分析软组织非均匀生长、病致变化、受限生长的失稳与后继形貌演化；发展数值方法模拟三维、曲面构型中软组织生长所致多次分岔、多重形貌转化的特征；并采用实验观测、层状仿体实验模拟软组织形貌演化特征，探索了研究结果在肿瘤发育与演化、癌症入侵等典型疾病临床诊疗上的潜在应用。