Comprehensive Biomaterials, Chapter 94 “The Mechanics of Native and Engineered Cardiac Soft Tissue”.

Characterization of the complete fiber network topology of planar fibrous tissues and scaffolds

Understanding how engineered tissue scaffold architecture affects cell morphology, metabolism, phenotypic expression, as well as predicting material mechanical behavior has recently received increased attention. In the present study, an image-based analysis approach that provides an automated tool to characterize engineered tissue fiber network topology is presented. Micro-architectural features that fully defined fiber network topology were detected and quantified, which include fiber orientation, connectivity, intersection spatial density, and diameter. Algorithm performance was tested using scanning electron microscopy (SEM) images of electrospun poly(ester urethane)urea (ES-PEUU) scaffo…

Unseeded Elastomeric Single Leaflets Retain Function and Remodel After Implant In Ovine Pulmonary Outflow Tract

Current materials for heart valve replacement and repair are limited by the inability to grow or remodel. Tissue engineered valves offer the potential to overcome these disadvantages by creating living structures, but is limited by the availability of biocompatible scaffold materials with desirable biomechanical properties. We assessed the in vivo performance of a novel scaffold poly(carbonate urethane) urea (PCUU), fabricated by electrospinning and implanted in the pulmonary outflow tract of sheep. PCUU was electrospun into elastomeric sheets of thickness ranging from 120-180 μm. Using cardiopulmonary bypass we replaced the native anterior pulmonary leaflet with an acellular PCUU leaflet. …

A Method to Extract the Complete Fiber Network Topology of Planar Fibrous Tissues and Scaffolds.

Improving fabrication protocols and design strategies, investigating on how scaffold architecture affects cell morphology, metabolism and phenotypic expression, predicting mechanical behaviors, have increasingly become crucial goals in the development of engineered tissue scaffolds. In the present study, an image-based analysis approach that provides an automatic tool to fully characterize engineered tissues fiber network topology was developed. The following micro architectural features are detected: fiber angle distribution, fiber connectivity, fiber overlap spatial density, fiber diameter. In order to demonstrate the potential of this approach Electrospun poly(ester urethane)urea (ES-PEU…

A NOVEL APPROACH TO FULLY CHARACTERIZE FIBER NETWORK MORPHOLOGY OF PLANAR FIBROUS TISSUES AND SCAFFOLDS

Comprendere come la struttura di uno scaffold influenzi la morfologia cellulare e predirne il comportamento meccanico sono divenuti obiettivi fondamentali nello sviluppo dei tessuti ingegnerizzati. In questo studio si presenta un algoritmo innovativo basato su analisi d’immagine. Vengono introdotti descrittori di micro architettura che identificano univocamente la topologia della rete di fibre: orientamento delle fibre, connettività, densità spaziale delle intersezioni e diametro. Le prestazioni dell’algoritmo sono state valutate utilizzando immagini di microscopio a scansione elettronica (SEM) di (1) scaffolds in poliestere uretano-urea prodotti per elettrospinning, (2) gel di collagene se…

Biomaterials Science: An Introduction to Materials in Medicine, 3rd ed., Chapter I.1.4 Finite Element Analysis in Biomechanics