Cellular forces generated by the actomyosin cytoskeleton and transmitted to the extracellular matrix (ECM) through discrete, integrin-based protein assemblies, that is, focal adhesions, are critical to developmental morphogenesis and tissue homeostasis, as well as disease progression in cancer. However, quantitative mapping of these forces has been difficult since there has been no experimental...

Native cell-material interactions occur on materials differing in their structural composition, chemistry, and physical compliance. While the last two decades have shown the importance of traction forces during cell-material interactions, they have been almost exclusively presented on purely elastic in vitro materials. Yet, most bodily tissue materials exhibit some level of viscoelasticity, whi...

To address the question of how cell-generated forces regulate the organization and function of endothelial cells, I investigated the mechanical forces in a simple model of cell-cell contact: paired cells contacting each other via a single cell-cell junction. To study the responsiveness of AJs to force, I adapted a system of microfabricated force sensors to quantitatively report both the cell-ce...

We combine traction force data with Bayesian inversion to obtain an absolute estimate of the internal stress field of a cell monolayer. The method, Bayesian inversion stress microscopy, is validated using numerical simulations performed in a wide range of conditions. It is robust to changes in each ingredient of the underlying statistical model. Importantly, its accuracy does not depend on the ...

Cells must exert force against the substrate to migrate. We examined the vectors (both the direction and the magnitude) of the traction force generated by Dictyostelium cells using an improved non-wrinkling silicone substrate. During migration, the cells showed two 'alternate' phases of locomotory behavior, an extension phase and a retraction phase. In accordance with these phases, two alternat...

Traction forces increase after microtubule depolymerization; however, the signaling mechanisms underlying this, in particular the dependence upon myosin II, remain unclear. We investigated the mechanism of traction force increase after nocodazole-induced microtubule depolymerization by applying traction force microscopy to cells cultured on micropatterned polyacrylamide hydrogels to obtain samp...

This study was performed for the purpose of comparing the magnitude of cervical vertebral separation during cervical traction in supine and seated positions using home traction units. A repeated measures design with two within-subject factors (type of traction and time) was used. Seventeen asymptomatic volunteers received cervical traction in seated and supine position. Subjects received 5 minu...

conclusions bilateral anterior shoulder dislocation is very rare. the excessive traction force during closed reduction may lead to nerve palsy. clear documentation of neurovascular status and adequate imaging before and after a reduction should be performed. introduction unilateral anterior shoulder dislocation is one of the most common problems encountered in orthopedic practice. however, simu...

Relations between primary oesophageal peristaltic amplitude and traction force were studied in 30 normal volunteers, 12 patients with functional dysphagia, and 48 patients with gastro-oesophageal reflux disease, using a new intraluminal strain gauge device. Forces generated by swallowing in the normal oesophagus were 42 (35-60) g (median and interquartile range), a close positive correlation ex...

The coordination of protrusion with retraction is essential for continuous cell movement. In fish keratocytes the activation of stretch-activated calcium channels, and the resulting increase in intracellular calcium, trigger release of the rear cell margin when forward movement is impeded. Although it is likely that retraction involves a calcium-dependent increase in cytoskeletal contractility,...