Conception et validation d'un biomatériau hybride pour la régénération osseuse

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Incorporation de fibronectine et d'albumine de sérum bovin à un biopolymère composé de polypyrrole et de poly (L-acide lactique) pour promouvoir la régénération tissulaire

Les biomatériaux jouent un rôle majeur dans le développement du génie tissulaire. Au cours des dernières années, les propriétés physiques, chimiques, et en particulier biologiques de ces matériaux ont été optimisées pour différentes applications. Le polypyrrole (PPy) électriquement conducteur et ses matières composites sont utiles pour connecter des composants électriques, des cellules ou des tissus vivants. Des efforts ont été faits pour bio-activer le PPy en incorporant électrochimiquement des biomolécules comme l'héparine et l'acide hyaluronique. Cette méthode est cependant limitée par la petite taille des électrodes, la dénaturation des biomolécules pendant les réactions électrochimiques, le changement des propriétés physiques et surtout la conductivité du polypyrrole. Le but de cette étude est de bio-activer le polypyrrole par l'incorporation de molécules bio-actives telles que la fibronectine et l'albumine de sérum bovin. Ce biomatériau serait d'une grande utilité dans le domaine de l'ingénierie tissulaire et constituerait un support bioactif, biodégradable et électriquement conducteur pour la culture de différents types cellulaires avec de multiples applications biomédicale

Effects of Different Titanium Surfaces Created by 3D Printing Methods, Particle Sizes, and Acid Etching on Protein Adsorption and Cell Adhesion, Proliferation, and Differentiation

The surfaces of 3D printed titanium prostheses have major impacts on the clinical performance of the prostheses. To investigate the surface effects of the products generated by 3D printed titanium on osseointegration, six surface types of titanium discs produced by the direct metal laser sintering (DMLS) and electron beam melting (EBM) methods, with two sizes of titanium particles and post-printing acid etching, were used to examine the surface topography and to explore the protein adsorption, pro-inflammatory cytokine gene expressions, and MC3T3-E1 cell adhesion, proliferation, and differentiation. The EBM-printed disc showed a stripy and smooth surface without evidence of the particles used, while the DMLS surface contained many particles. After acid etching, small particles on the DMLS surface were removed, whereas the large particles were left. Moreover, distinct proteins with low molecular weights were attached to the 3D printed titanium discs but not to the pre-printing titanium particles. The small titanium particles stimulated the highest TNF-α and IL-6 gene expressions at 24 h. The alizarin red content and osteocalcin gene expression at day 21 were the highest in the groups of acid-etched discs printed by DMLS with the small particles and by EBM. Therefore, the acid-treated surfaces without particles favor osteogenic differentiation. The surface design of 3D printed titanium prostheses should be based on their clinical applications

Ankle and Foot Arthroplasty and Prosthesis: A Review on the Current and Upcoming State of Designs and Manufacturing

The foot and ankle serve vital roles in weight bearing, balance, and flexibility but are susceptible to many diverse ailments, making treatment difficult. More commonly, Total Ankle Arthroplasty (TAA) and Total Talus Replacement (TTR) are used for patients with ankle degeneration and avascular necrosis of the talus, respectively. Ankle prosthesis and orthosis are also indicated for use with lower limb extremity amputations or locomotor disability, leading to the development of powered exoskeletons. However, patient outcomes remain suboptimal, commonly due to the misfitting of implants to the patient-specific anatomy. Additive manufacturing (AM) is being used to create customized, patient-specific implants and porous implant cages that provide structural support while allowing for increased bony ingrowth and to develop customized, lightweight exoskeletons with multifunctional actuators. AM implants and devices have shown success in preserving stability and mobility of the joint and achieving fast recovery, as well as significant improvements in gait rehabilitation, gait assistance, and strength for patients. This review of the literature highlights various devices and technologies currently used for foot and ankle prosthesis and orthosis with deep insight into improvements from historical technologies, manufacturing methods, and future developments in the biomedical space

Correction: MicroRNA-200c Represses IL-6, IL-8, and CCL-5 Expression and Enhances Osteogenic Differentiation.

[This corrects the article DOI: 10.1371/journal.pone.0160915.]

<i>miR-200c</i> delivered using PEI nanoparticles inhibits IL-6, IL-8, and CCL-5 in primary human periodontal ligament fibroblasts.

<p><b>A-C</b>: The transcripts of IL-6 (<b>A</b>), IL-8 (<b>B</b>), and CCL-5 (<b>C</b>) in the cells with <i>miR-200c</i> or empty vector cultured in DMEM supplemented with LPS after 24 hours; <b>D</b> and <b>E</b>: the amounts of IL-6 (<b>D</b>), IL-8 (<b>E</b>), and CCL-5 (<b>F</b>) secreted by the cells with miR-200c or empty vector cultured in DMEM supplemented with LPS after 12 and 32 hrs, respectively. *: p<0.05 vs empty vector with the same amount.</p

<i>miR-200c</i> modulates proinflammatory mediators in human preosteoblasts.

<p><b>A</b> and <b>B:</b> the transcripts of IL-6 <b>(A)</b> and IL-8 (<b>B</b>) in non-treated HEPM cells and the cells with <i>miR-200c</i> or scrambled <i>miRs</i> cultured in DMEM supplemented with LPS at 0, 1, 5 and 10 μg/mL after 24 hours; *:p<0.05 vs non-treated; <b>C:</b> the amounts of IL-8 secreted by HEPM cells with <i>miR-200c</i> or scrambled <i>miRs</i> cultured in DMEM supplemented with or without LPS at different time points; *: p<0.05 vs cells with scrambled miRs; <b>D</b> and <b>E:</b> the amounts of IL-6 (<b>D</b>) and CCL-5 (<b>E</b>) secreted by HEPM cells with <i>miR-200c</i> or <i>scrambled miRs</i> cultured in DMEM supplemented with or without LPS after 24 hrs; <b>F:</b> the amounts of OPG secreted by HEPM cells with different <i>miRs</i> cultured in DMEM supplemented with or without LPS after 32 hours. *: p<0.05.</p