The extracellular matrix microtopography drives critical changes in cellular motility and Rho A activity in colon cancer cells

We have shown that the microtopography (mT) underlying colon cancer changes as a tumor de-differentiates. We distinguish the well-differentiated mT based on the increasing number of "pits" and poorly differentiated mT on the basis of increasing number of "posts." We investigated Rho A as a mechanosensing protein using mT features derived from those observed in the ECM of colon cancer. We evaluated Rho A activity in less-tumorogenic (Caco-2 E) and more tumorigenic (SW620) colon cancer cell-lines on microfabricated pits and posts at 2.5 μm diameter and 200 nm depth/height. In Caco-2 E cells, we observed a decrease in Rho A activity as well as in the ratio of G/F actin on surfaces with either pits or posts but despite this low activity, knockdown of Rho A led to a significant decrease in confined motility suggesting that while Rho A activity is reduced on these surfaces it still plays an important role in controlling cellular response to barriers. In SW620 cells, we observed that Rho A activity was greatest in cells plated on a post microtopography which led to increased cell motility, and an increase in actin cytoskeletal turnover

Continuum-kinetic model for cell adhesion and movement

A computational approach for studying the adhesion kinetics and deformation of a cell on a substrate is presented. It is shown that the cell mechanical properties and surrounding fluid dynamics affect the receptor-ligand kinetics, and that these effects need to be included in any realistic cellsurface interaction models

Hydrodynamic force on a viscous cell sticking to a flat surface

The force of interaction between the endothelium wall and a viscous cell that is sticking or rolling on it is described. The flow over a cell sticking to a flat surface is analyzed using ELAFINT, a numerical method capable of tracking the evolution of distorted phase fronts in the presence of convective viscous flow. This computational method overcomes the limitations of conventional approaches by combining the features of both Eulerian and Lagrangian methods

Computational surgery and dual training

The new and emerging field of computational surgery will improve the efficiency and quality of surgery and will give patients access to very complex surgical operations that require extreme precision and minimum intrusion. In order to effectively deploy computational surgery techniques in life threatening cases such as inoperable cancer tumors that have invaded critical artery tissues or the nervous system, surgeons will have to become very familiar with computing methods, such as image analysis, augmented reality and robotics. Computational Surgery and Dual Training provides the necessary background in computer and surgical techniques that will enable computer scientists/biomedical engineers and surgeons to work together to improve interventional procedures and surgeries. The book brings together contributions from leading minds in the field, who also: Provide a foundation in surgical methods for biomedical engineers who wish to do research in the surgical area Include material on surgery applications and biomedical modeling Offer a detailed discussion of imaging and optimization in computational surgery Computational Surgery and Dual Training is the perfect book for biomedical engineers and active surgeons interested in learning more about these developing methods. © Springer Science+Business Media, LLC 2010. All rights reserved