Search results for "folds"

Cardiac tissue engineering: a reflection after a decade of hurry

2014

The heart is a perfect machine whose mass is mainly composed of cardiomyocytes, but also fibroblasts, endothelial, smooth muscle, nervous, and immune cells are represented. One thousand million cardiomyocytes are estimated to be lost after myocardial infarction, their loss being responsible for the impairment in heart contractile function (Laflamme and Murry, 2005). The potential success of cardiac cell therapy relies almost completely on the ability of the implanted cells to differentiate toward mature cardiomyocytes. These cells must be able to reinforce the pumping activity of the injured heart in the absence of life-threatening arrhythmias due to electrophysiological incompatibility. Th…

APPROXIMATE INERTIAL MANIFOLDS FOR THERMODIFFUSION EQUATIONS

2004

In this paper, we consider the two dimensional equations of thermohydraulics, i.e. the coupled system of equations of fluid and temperature in the Boussinesq approximation. We construct a family of approximate Inertial Manifolds whose order decreases exponentially fast with respect to the dimension of the manifold. We give the explicit expression of the order of the constructed manifolds.

Establishment of a pulmonary epithelial barrier on biodegradable poly-L-lactic-acid membranes

2019

Development of biocompatible and functional scaffolds for tissue engineering is a major challenge, especially for development of polarised epithelia that are critical structures in tissue homeostasis. Different in vitro models of the lung epithelial barrier have been characterized using non-degradable polyethylene terephthalate membranes which limits their uses for tissue engineering. Although poly-L-lactic acid (PLLA) membranes are biodegradable, those prepared via conventional Diffusion Induced Phase Separation (DIPS) lack open-porous geometry and show limited permeability compromising their use for epithelial barrier studies. Here we used PLLA membranes prepared via a modification of the…

Preparation of Poly(l-lactic acid) Scaffolds by Thermally Induced Phase Separation: Role of Thermal History

2018

Abstract Poly-L-Lactic Acid (PLLA) scaffolds for tissue engineering were prepared via thermally induced phase separation of a ternary system PLLA/dioxane/tetrahydrofurane. An extension to solution of a previously developed method for solidification from the melt was adopted, the technique being based on a Continuous Cooling Transformation (CCT) approach, consisting in recording the thermal history of rapidly cooled samples and analysing the resulting morphology. Different foams were produced by changing the thermal history, the dioxane to THF ratio (50/50, 70/30, 90/10 v/v) and the polymer concentration (2, 2.5, 4 ° wt) in the starting ternary solution. Pore size, porosity, melting and crys…

3D cultures of rat astrocytes and brain capillary endothelial cells on Poly-L-lactic acid scaffolds

2016

Tissue engineering is an emerging multidisciplinary field that aims at reproducing in vitro and/or in vivo tissues with morphological and functional features similar to the biological tissue of the human body. In this communication we report setting of three-dimensional structures able to mimic the extracellular matrix of the nervous system: we prepared Poly-L-Lactic Acid (PLLA) porous scaffolds via thermally induced phase separation (TIPS), and investigated the parameters that influence porosity, average pore size and degree of interconnection, i.e. polymer concentration, temperature and time of process. Astrocytes and brain capillary endothelial cells (BCECs) were cultured on these three-…

Biocompatibility evaluation of PLLA scaffolds for vascular tissue engineering

2015

Poly-L-lactic acid (PLLA), a hemicrystalline material, has been extensively studied in applications of engineered tissues, because it is biodegradable, absorbable and it supports cell attachment and growth. The purpose of this study is to evaluate tissue/ material interactions, neovascularization and the biocompatibility of PLLA by optical and scanning electron microscopy in a model of animal implant. PLLA porous disks were implanted into the dorsal subcutis of BALB/C mice for 1, 2, 3, and 8 weeks. The bioptic samples of excised PLLA and the surrounding tissue were evaluated for inflammatory response and tissue ingrowth. The samples were divided in two halves: one was fixed in neutral buffe…

Polyaspartamide-polylactide electrospun scaffolds for potential topical release of ibuprofen

2012

A facile and eco-friendly route to fabricate poly(Lactic acid) scaffolds with graded pore size

2016

Over the recent years, functionally graded scaffolds (FGS) gaineda crucial role for manufacturing of devices for tissue engineering. The importance of this new field of biomaterials research is due to the necessity to develop implants capable of mimicking the complex functionality of the various tissues, including a continuous change from one structure or composition to another. In this latter context, one topic of main interest concerns the design of appropriate scaffolds for bone-cartilage interface tissue. In this study, three-layered scaffolds with graded pore size were achieved by melt mixing poly(lactic acid) (PLA), sodium chloride (NaCl) and polyethylene glycol (PEG). Pore size distr…

Poly(ethylenglycol) mimics adhesive capability of the ECM treatment on 3D polylactide-based scaffolds to study in vitro human hepatocarcinoma process…

2011

Late consequences of traumatic rupture of the diaphragm.

2013

A 54-year-old man was admitted to our clinic due to elevated γ-glutamyltransferase, without any clinical symptoms. About 25 years ago, he had undergone blunt abdominal and thoracic trauma during an accident. No diagnostic measures or therapy had been performed at that time. Serum bilirubin was normal, but the values for alanine transaminase, aspartate transaminase, and alkaline phosphatase were slightly above the reference range. Sonography of the abdomen revealed dilated intrahepatic bile ducts up to 3 mm in diameter and steatosis of the liver grade I. CT scan and MRI of the thorax and abdomen showed a giant hiatal hernia with transposition of upper abdominal organs into the chest. As the …