The role of mechanical interactions in EMT

The detachment of cells from the boundary of an epithelial tissue and the subsequent invasion of these cells into surrounding tissues is important for cancer development and wound healing, and is strongly associated with the epithelial-mesenchymal transition (EMT). Chemical signals, such as TGF-beta, produced by surrounding tissue can be uptaken by cells and induce EMT. In this work, we present a novel cell-based discrete mathematical model of mechanical cellular relaxation, cell proliferation, and cell detachment driven by chemically-dependent EMT in an epithelial tissue. A continuum description of the model is then derived in the form of a novel nonlinear free boundary problem. Using the discrete and continuum models we explore how the coupling of chemical transport and mechanical interactions influences EMT, and postulate how this could be used to help control EMT in pathological situations.

Discourse of psychoactive substance dependents on their discursively constructed image

ABSTRACT Objective: to analyze the discourse of psychoactive substance users undergoing treatment regarding their image of themselves as drug dependent subjects, of other dependents and the social position assumed by them. Method: qualitative study conducted between March and September of 2016 through a semi-structured interview and drawings, based on the theoretical-methodological reference of French Discourse Analysis. Participation of 12 drug dependent subjects undergoing treatment in the service that substitutes the asylum. Results: The images that psychoactive substance dependents have of themselves and of chemically dependent subjects are associated with the image of a negative, diabolical, transgressive, sick and socially excluded individual. Final considerations: The ideological effects of meanings produced by users’ discourses reproduce the biological and moral model. Health professionals, including nurses, need to invest in discourses that address the psychosocial model to demythologize this stigmatizing image and modify their work practice.