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Noble Birk posted an update 1 week ago
The NF fiber density reached to 29 ± 6 per 0.25 mm2 at the middle site, 82 ± 13 per 0.25 mm2 at the adjacent caudal site, and 70 ± 23 at the adjacent rostral site. Similarly, motor axons labeled with 5-hydroxytryptamine were significantly regenerated in the injury gap, which was 122 ± 22 at the middle injury site that was beneficial for motor function recovery. Most remarkably, the transplantation of MSC-laden microfibers significantly improved electrophysiological expression and re-established limb motor function. These findings highlight the combination of MSCs with microhydrogel fibers, the use of which may become a promising method for MSC implantation and SCI repair.Biomaterial-associated infections often arise from contaminating bacteria adhering to an implant surface that are introduced during surgical implantation and not effectively eradicated by antibiotic treatment. Whether or not infection develops from contaminating bacteria depends on an interplay between bacteria contaminating the biomaterial surface and tissue cells trying to integrate the surface with the aid of immune cells. The biomaterial surface plays a crucial role in defining the outcome of this race for the surface. Tissue integration is considered the best protection of a biomaterial implant against infectious bacteria. This paper aims to determine whether and how macrophages aid osteoblasts and human mesenchymal stem cells to adhere and spread over gold nanoparticle (GNP)-coatings with different hydrophilicity and roughness in the absence or presence of contaminating, adhering bacteria. All GNP-coatings had identical chemical surface composition, and water contact angles decreased with increasing rounce of Gram-negative E. coli. Thus, the merits on GNP-coatings to influence the race for the surface and prevent biomaterial-associated infection critically depend on their hydrophilicity/roughness and the bacterial strain involved in contaminating the biomaterial surface.Hydrogels produced by self-assembling peptides are intrinsically biocompatible and thus appropriate for many biomedical purposes. Their application field may be even made wider by reducing the softness and improving the hydrogel mechanical properties through cross-linking treatments. To this aim, modifications of EAK16-II sequence by including Cys residues in its sequence were here investigated in order to obtain hydrogels cross-linkable through a disulfide bridge. Two sequences, namely, C-EAK and C-EAK-C, that contain Cys residues at the N-terminus or at both ends were characterized. Fiber-forming abilities and biological and dynamic mechanical properties were explored before and after the oxidative treatment. In particular, the oxidized version of C-EAK presents a good cell viability and sustains osteoblast proliferation. Furthermore, molecular dynamics (MD) simulations on monomeric and assembled forms of the peptides were performed. MD simulations explained how a specific Cys functionalization was better than the other one. In particular, the results suggested that EAK16-II functionalization with a single Cys residue, instead of two, together with biocompatible cross-linking may be considered an intriguing strategy to obtain a support with better dynamic mechanical properties and biological performances.Three-dimensional (3D) scaffolds with tailored stiffness, porosity, and conductive properties are particularly important in tissue engineering for electroactive cell attachment, proliferation, and vascularization. see more Carbon nanotubes (CNTs) and poly(3,4-ethylenedioxythiophene) (PEDOT) have been extensively used separately as neural interfaces showing excellent results. Herein, we combine both the materials and manufacture 3D structures composed exclusively of PEDOT and CNTs using a methodology based on vapor phase polymerization of PEDOT onto a CNT/sucrose template. Such a strategy presents versatility to produce porous scaffolds, after leaching out the sucrose grains, with different ratios of polymer/CNTs, and controllable and tunable electrical and mechanical properties. The resulting 3D structures show Young’s modulus typical of soft materials (20-50 kPa), as well as high electrical conductivity, which may play an important role in electroactive cell growth. The conductive PEDOT/CNT porous scaffolds present high biocompatibility after 3 and 6 days of C8-D1A astrocyte incubation.Myocardial infarction (MI) causes cardiac cell death, induces persistent inflammatory responses, and generates harmful pathological remodeling, which leads to heart failure. Biomedical approaches to restore blood supply to ischemic myocardium, via controlled delivery of angiogenic and immunoregulatory proteins, may present an efficient treatment option for coronary artery disease (CAD). Vascular endothelial growth factor (VEGF) is necessary to initiate neovessel formation, while platelet-derived growth factor (PDGF) is needed later to recruit pericytes, which stabilizes new vessels. Anti-inflammatory cytokines like interleukin-10 (IL-10) can help optimize cardiac repair and limit the damaging effects of inflammation following MI. To meet these angiogenic and anti-inflammatory needs, an injectable polymeric delivery system composed of encapsulating micelle nanoparticles embedded in a sulfonated reverse thermal gel was developed. The sulfonate groups on the thermal gel electrostatically bind to VEGF and IL-10, and their specific binding affinities control their release rates, while PDGF-loaded micelles are embedded in the gel to provide the sequential release of the growth factors. An in vitro release study was performed, which demonstrated the sequential release capabilities of the delivery system. The ability of the delivery system to induce new blood vessel formation was analyzed in vivo using a subcutaneous injection mouse model. Histological assessment was used to quantify blood vessel formation and an inflammatory response, which showed that the polymeric delivery system significantly increased functional and mature vessel formation while reducing inflammation. Overall, the results demonstrate the effective delivery of therapeutic proteins to promote angiogenesis and limit inflammatory responses.