Micropartículas de PLLA y CHT como andamiaje para la regeneración del cartílago articular : modelo animal.

The avascular nature of cartilaginous tissue has historically lead to bad prognosis in osteochondral injuries. One of the possible treatment options of these injuries is the use of scaffolds, being superior to other options that obtain a fibrous cartilage as a result. We have elaborated PLLA and CHT microspheres as a scaffold for the treatment of osteochondral injuries carried out in albine New Zealand rabbits. They were distributed into groups with different proportions of microspheres, having also a control group with untreated injuries. Native cartilage of the contralateral knees was also analysed. Samples were evaluated in order to establish the quality of the cartilage obtained (using de macroscopic ICRS, microscopic ICRS II scales and a histomorphometric study).The groups with microspheres obtained a regeneration cartilage with hyaline characteristics, a good cell distribution and regular surface. The control group resulted in a cartilage with worse organization and an irregular surface

Macroporous thin membranes for cell transplant in regenerative medicine

The aim of this paper is to present a method to produce macroporous thin membranes made of poly (ethyl acrylate-co-hydroxyethyl acrylate) copolymer network with varying cross-linking density for cell transplantation and prosthesis fabrication. The manufacture process is based on template techniques and anisotropic pore collapse. Pore collapse was produced by swelling the membrane in acetone and subsequently drying and changing the solvent by water to produce 100 microns thick porous membranes. These very thin membranes are porous enough to hold cells to be transplanted to the organism or to be colonized by ingrowth from neighboring tissues in the organism, and they present sufficient tearing stress to be sutured with surgical thread. The obtained pore morphology was observed by Scanning Electron Microscope, and confocal laser microscopy. Mechanical properties were characterized by stress-strain experiments in tension and tearing strength measurements. Morphology and mechanical properties were related to the different initial thickness of the scaffold and the cross-linking density of the polymer network. Seeding efficiency and proliferation of mesenchymal stem cells inside the pore structure were determined at 2 hours, 1, 7, 14 and 21 days from seeding.This work was funded by the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2013-46467-C4-1-R (including the FEDER financial support). J.R.R. acknowledges funding of his PhD by the Generalitat Valenciana through VALi+d grant (ACIF/2010/238). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. The authors acknowledge too the advice of Dr. Daniel Kelly, Dr. Conor Buckley and Dr. Yurong Liu about the isolation and expansion of porcine MSCs. The authors acknowledge the assistance and advice of Electron Microscopy Service of the UPV.Antolinos Turpín, CM.; Morales Román, RM.; Ródenas Rochina, J.; Gómez Ribelles, JL.; Gómez-Tejedor, JA. (2015). Macroporous thin membranes for cell transplant in regenerative medicine. Biomaterials. 67:254-263. https://doi.org/10.1016/j.biomaterials.2015.07.032S2542636

Time evolution of in vivo articular cartilage repair induced by bone marrow stimulation and scaffold implantation in rabbits

Purpose: Tissue engineering techniques were used to study cartilage repair over a 12-month period in a rabbit model. Methods: A full-depth chondral defect along with subchondral bone injury were originated in the knee joint, where a biostable porous scaffold was implanted, synthesized of poly(ethyl acrylate-co-hydroxyethyl acrylate) copolymer. Morphological evolution of cartilage repair was studied 1 and 2 weeks, and 1, 3, and 12 months after implantation by histological techniques. The 3-month group was chosen to compare cartilage repair to an additional group where scaffolds were preseeded with allogeneic chondrocytes before implantation, and also to controls, who underwent the same surgery procedure, with no scaffold implantation. Results: Neotissue growth was first observed in the deepest scaffold pores 1 week after implantation, which spread thereafter; 3 months later scaffold pores were filled mostly with cartilaginous tissue in superficial and middle zones, and with bone tissue adjacent to subchondral bone. Simultaneously, native chondrocytes at the edges of the defect started to proliferate 1 week after implantation; within a month those edges had grown centripetally and seemed to embed the scaffold, and after 3 months, hyaline-like cartilage was observed on the condylar surface. Preseeded scaffolds slightly improved tissue growth, although the quality of repair tissue was similar to non-preseeded scaffolds. Controls showed that fibrous cartilage was mainly filling the repair area 3 months after surgery. In the 12-month group, articular cartilage resembled the untreated surface. Conclusions: Scaffolds guided cartilaginous tissue growth in vivo, suggesting their importance in stress transmission to the cells for cartilage repair.This study was supported by the Spanish Ministry of Science and Innovation through MAT2010-21611-C03-00 project (including the FEDER financial support), by Conselleria de Educacion (Generalitat Valenciana, Spain) PROMETEO/2011/084 grant, and by CIBER-BBN en Bioingenieria, Biomateriales y Nanomedicina. The work of JLGR was partially supported by funds from the Generalitat Valenciana, ACOMP/2012/075 project. CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the - Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Sancho-Tello Valls, M.; Forriol, F.; Gastaldi, P.; Ruiz Sauri, A.; Martín De Llano, JJ.; Novella-Maestre, E.; Antolinos Turpín, CM.... (2015). 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Physical ageing of amorphous polymers. Theroretical analysis and experiments on poly(methyl methacrylate)

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Novel poly(vinylidene fluoride-trifluoroethylene)/poly(ethylene oxide) blends for battery separators in lithium-ion applications

Polymer blends based on poly(vinylidene fluoride-trifluoroethylene)/poly(ethylene oxide), P(VDF-TrFE)/PEO for Li-ion battery separators applications have been prepared through solvent casting technique. The microstructure, hidrophilicity and electrolyte uptake strongly depend on PEO content within the blend. The best value of ionic conductivity at room temperature was 0.25 mS.cm-1 for the 60/40 membrane. The membranes are electrochemically stable.This work is funded by FEDER funds through the "Programa Operacional Factores de Competitividade – COMPETE" and by national funds by FCT- Fundação para a Ciência e a Tecnologia, project references Project PTDC/CTM/69316/2006, NANO/NMed-SD/0156/2007 and Pest-C/QUI/UIO686/2011 and grant SFRH/BD/68499/2010 (C.M.C) and SFRH/BD/66930/2009 (J.N.P.). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund

Fatigue prediction in fibrin poly-ε-caprolactone macroporous scaffolds

Tissue engineering applications rely on scaffolds that during its service life, either for in-vivo or in vitro applications, are under loading. The variation of the mechanical condition of the scaffold is strongly relevant for cell culture and has scarcely been addressed. The fatigue life cycle of poly-ε-caprolactone, PCL, scaffolds with and without fibrin as filler of the pore structure were characterized both dry and immersed in liquid water. It is observed that the there is a strong increase from 100 to 500 in the number of loading cycles before collapse in the samples tested in immersed conditions due to the more uniform stress distributions within the samples, the fibrin loading playing a minor role in the mechanical performance of the scaffolds.This work is funded by FEDER funds through the "Programa Operacional Factores de Competitividade – COMPETE" and by national funds arranged by FCT- Fundação para a Ciência e Tecnologia, project references NANO/NMed-SD/0156/2007, PTDC/CTM-NAN/112574/2009 and PEST-C/FIS/UI607/2011. The authors also thank funding from Matepro –Optimizing Materials and Processes”, ref. NORTE-07-0124-FEDER-000037”, co-funded by the “Programa Operacional Regional do Norte” (ON.2 – O Novo Norte), under the “Quadro de Referência Estratégico Nacional” (QREN), through the “Fundo Europeu de Desenvolvimento Regional” (FEDER). JAP and VS thank the FCT for the SFRH/BD/64586/2009/ and SFRH/BPD/63148/2009 grants, respectively. JLGR acknowledge the support of the Spanish Ministry of Science and Innovation through project No. MAT2010-21611-C03-01 (including the FEDER financial support). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund

Effect of the degree of porosity on the performance of poly(vinylidene fluoride-trifluoroethylene)/poly(ethylene oxide) blend membranes for lithium-ion battery separators

Porous polymer membranes based on poly(vinylidene fluoride-trifluoroethylene)/poly(ethylene oxide) copolymers, P(VDF-TrFE)/PEO, are prepared through the, from partial to total, elimination of PEO, leading to interconnected micropores in the polymer blends. Electrolyte uptake, thermal and mechanical properties depend on the amount of PEO present in the polymer blend. Further, the degree of crystallinity of PEO and the elastic modulus (E´) of the polymer blend decrease with increasing PEO removal. Electrical properties of the polymer blend membranes are influenced by the porosity and are dominated by diffusion. The temperature dependence of ionic conductivity follows the Arrhenius behavior. It is the highest for the membranes with a volume fraction of pores of 44% (i.e, 90% PEO removal), reaching a value of 0.54 mS.cm-1 at room temperature. Battery performance was determined by assembling Li/C-LiFePO4 swagelok cells. The polymer blends with 90% PEO removal exhibit rate (124 mAhg-1 at C/5 and 47 mAhg-1 at 2C) and cycling capabilities suitable for lithium ion battery applications.This work is funded by FEDER funds through the “Programa Operacional Factores de Competitividade–COMPETE” and by national funds from FCT–Fundação para a Ciência e a Tecnologia, in the framework of the strategic project Strategic Projects PEST-C/FIS/UI607/2013, PEST-C/QUI/UI0686/2013 and grants SFRH/BD/68499/2010 (C.M.C.), SFRH/BD/90313/2012 (A.G.) and SFRH/BD/66930/2009 (J.N.P.). The authors thank funding from “Matepro–Optimizing Materials and Processes”, ref. NORTE-07-0124-FEDER-000037”, co-funded by the “Programa Operacional Regional do Norte” (ON.2–O Novo Norte), under the “Quadro de Referência Estratégico Nacional”(QREN), through the “Fundo Europeu de Desenvolvimento Regional” (FEDER). JLGR acknowledges the support of the Ministerio de Economía y Competitividad, MINECO, through the MAT2013-46467-C4-1-R project (including FEDER finantial support). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008– 2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund