Search results for "tissue engineering"
showing 10 items of 370 documents
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…
Characterization of PLLA scaffolds for biomedical applications
2017
The porosity and pore size distribution of three-dimensional scaffolds have direct implications on their biomedical applications (tissue engineering, drug delivery, and wound dressing). Accordingly, in this paper, a fast, facile, and conservative method relying on low-field nuclear magnetic resonance (LF-NMR) for the evaluation of mean pore size and pore size distribution of polymeric scaffolds is reported. The applicability of the technique is demonstrated on poly-L-lactic acid scaffolds fabricated using the thermal induced phase separation. Results obtained through LF-NMR are successfully compared to scanning electron microscope and X-ray microcomputed tomography micrographs.
Hypoxia-induced dysfunction of rat diaphragm
2004
Contains fulltext : 47331.pdf (Publisher’s version ) (Closed access) Oxidants may play a role in hypoxia-induced respiratory muscle dysfunction. In the present study we hypothesized that hypoxia-induced impairment in diaphragm contractility is associated with elevated peroxynitrite generation. In addition, we hypothesized that strenuous contractility of the diaphragm increases peroxynitrite formation. In vitro force-frequency relationship, isotonic fatigability, and nitrotyrosine levels were assessed under hypoxic (Po(2) approximately 6.5 kPa) and hyperoxic (Po(2) approximately 88.2 kPa) control conditions and also in the presence of authentic peroxynitrite (60 min), ebselen (60 min), and t…
Unseeded Elastomeric Single Leaflets Retain Function and Remodel After Implant In Ovine Pulmonary Outflow Tract
2013
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. …
Poly(vinyl alcohol)/κ-Carrageenan-based hydrogels enriched with the adhesive mussel protein Pvfp5β as 3D cell culture scaffold for tissue engineering…
2021
Many marine organisms such as sandcastle worms, barnacles and mussels, produce natural adhesives to attach to wet surfaces in aqueous tidal environments. In mussels, the adhesion is possible through the secretion of a protein-based water-resistant glue, composed of a mixture of proteins called mussel adhesive proteins (MAPs) or mussel foot proteins (mfps), that allow anchoring to almost any kind of surface in wet conditions [1]. The proteins confined to adhesive plaques are mfp-2, -3, -4, -5, and -6. All these proteins contain an atypically high concentration of the catecholic amino acid 3,4- dihydroxy-l-phenylalanine (DOPA), obtained by the post-translational enzymatic hydroxylation of tyr…
Alginate-Agarose Hydrogels Improve the In Vitro Differentiation of Human Dental Pulp Stem Cells in Chondrocytes. A Histological Study
2021
[EN] Matrix-assisted autologous chondrocyte implantation (MACI) has shown promising results for cartilage repair, combining cultured chondrocytes and hydrogels, including alginate. The ability of chondrocytes for MACI is limited by different factors including donor site morbidity, dedifferentiation, limited lifespan or poor proliferation in vitro. Mesenchymal stem cells could represent an alternative for cartilage regeneration. In this study, we propose a MACI scaffold consisting of a mixed alginate-agarose hydrogel in combination with human dental pulp stem cells (hDPSCs), suitable for cartilage regeneration. Scaffolds were characterized according to their rheological properties, and their…
Nanotechnology, and scaffold implantation for the effective repair of injured organs: An overview on hard tissue engineering
2020
The tissue engineering of hard organs and tissues containing cartilage, teeth, and bones is a widely used and rapidly progressing field. One of the main features of hard organs and tissues is the mineralization of their extracellular matrices (ECM) to enable them to withstand pressure and weight. Recently, a variety of printing strategies have been developed to facilitate hard organ and tissue regeneration. Fundamentals in three-dimensional (3D) printing techniques are rapid prototyping, additive manufacturing, and layered built-up and solid-free construction. This strategy promises to replicate the multifaceted architecture of natural tissues. Nowadays, 3D bioprinting techniques have prove…
A new polyphosphate calcium material with morphogenetic activity
2015
Abstract Polyphosphate [polyP] has been proven to elicit morphogenetic activity on bone cells. By applying mild reaction conditions, a Ca-polyP material that displays a hardness of ≈1.3 GPa has been fabricated. The Ca-polyP granules are prone to hydrolytic degradation during in vitro incubation of the cells, suggesting that this property is associated with the observed bioactivity.
Dentin tubule orientation determines odontoblastic differentiation in vitro: A morphological study.
2019
Odontoblasts are post-mitotic cells responsible for maintenance of the dentin, and are therefore important for dental health. In some cases, irreversible pulpitis leads to necrosis and consequently death of odontoblasts. Regenerative endodontics (RE) uses the concept of tissue engineering to restore the root canals to a healthy state, allowing for continued development of the root and surrounding tissue. Human dental pulp stem cells (hDPSCs) have been successfully used in RE to restore odontoblast function. Surface microgeometry is one of the most important factors involved in the induction of differentiation of hDPSCs into odontoblast-like cells. Although different authors have demonstrate…
The sharing of research data in the cell & Tissue engineering area: Is it a common practice?
2018
The availability of research data sets is an important milestone because it can enhance the dynamics of research. This study aims to analyze the PubMed Central repository to determine the availability and type of raw data sets in Cell & Tissue Engineering journals indexed in Journal Citation Reports. The number and types of files were registered. The main finding of this study is that, beyond the mandatory deposit of data in specific repositories that some journals require, the exchange of data as supplementary material in the Cell & Tissue Engineering journals is not a common practice since researchers are still reticent to do so.