Active Osteoblasts or Quiescent Bone Lining Cells? Preosteoblasts Fate Orchestrated by Curvature and Stiffness of an In Vitro 2.5D Biomimetic Culture System.

Biomimetic cell culture systems are required to provide more physiologically relevant microenvironments for bone cells. Here, a simple 2.5D culture platform is proposed, combining adjustable stiffness and surface features that mimic bone topography by using sandpaper grits as master molds with two stiffness formulations of polydimethylsiloxane (PDMS).

Gaseous NO induces various envelope alterations in Pseudomonas fluorescens MFAF76a.

Anthropogenic atmospheric pollution and immune response regularly expose bacteria to toxic nitrogen oxides such as NO and NO. These reactive molecules can damage a wide variety of biomolecules such as DNA, proteins and lipids. Several components of the bacterial envelope are susceptible to be damaged by reactive nitrogen species.

Hyaluronan-based hydrogels as versatile tumor-like models: Tunable ECM and stiffness with genipin-crosslinking.

Three-dimensional (3D) biomimetic cell culture platforms offer more realistic microenvironments that cells naturally experience in vivo. We developed a tunable hyaluronan-based hydrogels that could easily be modified to mimic healthy or malignant extracellular matrices (ECMs). For that, we pre-functionalized our hydrogels with an adhesive polypeptide (poly-l-lysine, PLL) or ECM proteins (type III and type IV collagens), naturally present in tumorous tissues, and next, we tuned their stiffness by crosslinking with gradual concentrations of genipin (GnP).

Iron-loaded amine/thiol functionalized polyester fibers with high catalytic activities: a comparative study.

Dispersion of iron nanoparticles (Fe-NPs) was achieved on polyester fabrics (PET) before and after the incorporation of dendrimers (PAMAM), 3-(aminopropyl) triethoxysilane (APTES) or thioglycerol (SH). The catalytic activity of the resulting materials (PET-Fe, PET-PAMAM-Fe, PET-APTES-Fe and PET-SH-FE) was comparatively investigated in the degradation of 4-nitrophenol (4-NP) and methylene-blue (MB). Full characterization through diverse instrumental methods allowed correlating the type of the organic moiety incorporated with the Fe content, catalytic properties and stability.

Synergistic influence of topomimetic and chondroitin sulfate-based treatments on osteogenic potential of Ti-6Al-4V.

We combined topographical and chemical surface modifications of Ti-6Al-4V (TA6V) to improve its osteogenic potential. By acid-etching, we first generated topomimetic surface features resembling, in size and roughness, bone cavities left by osteoclasts. Next, we coated these surfaces with biomimetic Layer-by-Layer films (LbL), composed of chondroitin sulfate A and poly-l-lysine that were mechanically tuned after a post-treatment with genipin.