Glucose depletion decreases cell viability without triggering degenerative changes in a physiological nucleus pulposus explant model.

Although the etiology of intervertebral disc degeneration is still unresolved, the nutrient paucity resulting from its avascular nature is suspected of triggering degenerative processes in its core: the nucleus pulposus (NP). While severe hypoxia has no significant effects on NP cells, the impact of glucose depletion, such as found in degenerated discs (0.2-1 mM), is still uncertain.

3D-Printed Osteoinductive Polymeric Scaffolds with Optimized Architecture to Repair a Sheep Metatarsal Critical-Size Bone Defect.

The reconstruction of critical-size bone defects in long bones remains a challenge for clinicians. A new osteoinductive medical device is developed here for long bone repair by combining a 3D-printed architectured cylindrical scaffold made of clinical-grade polylactic acid (PLA) with a polyelectrolyte film coating delivering the osteogenic bone morphogenetic protein 2 (BMP-2). This film-coated scaffold is used to repair a sheep metatarsal 25-mm long critical-size bone defect.

The Lower in Vivo Osteogenicity of Adipose Tissue-Derived Stem Cells Correlates with a Higher Innate Immune Response.

Adipose tissue-derived mesenchymal stem cells (ATSCs) have been used as an alternative to bone marrow-derived mesenchymal stem cells (BMSCs) for bone tissue engineering applications. The ability of ATSCs to promote new bone formation remains lower than that of BMSCs. This study aimed to investigate the mechanisms underlying osteogenicity differences between human ATSCs and BMSCs in ceramic constructs, focusing on the effects of inflammation on this process.

Targeted resequencing of the 13q13 spondyloarthritis-linked locus identifies a rare variant in FREM2 possibly associated with familial spondyloarthritis.

Objectives: The strong heritability of spondyloarthritis remains poorly explained, despite several large-scale association studies. A recent linkage analysis identified a new region linked to SpA on 13q13. Here we searched for variants potentially explaining this linkage signal by deep-sequencing of the region.

Remnants-preserving ACL reconstruction using direct tendinous graft fixation: a new rat model.

Background: Anterior cruciate ligament (ACL) repair techniques are new emerging strategies prevailing, in selected cases, over standard reconstruction of the ACL with excision of its remnants. Mid-substance ACL tears represent a challenge for ACL repair techniques, and remnants-preserving ACL reconstruction (rp-ACLR) using an autograft remains the recommended treatment in this situation. However, morbidity associated with the autograft harvesting prompts the need for alternative surgical strategies based on the use of synthetic scaffolds.

Osteogenic-differentiated mesenchymal stem cell-secreted extracellular matrix as a bone morphogenetic protein-2 delivery system for ectopic bone formation.

While human bone morphogenetic protein-2 (BMP-2) is a promising growth factor for bone regeneration, a major challenge in biomedical applications is finding an optimal carrier for its delivery at the site of injury. Because of their natural affinities for growth factors (including BMP-2) as well as their role in instructing cell function, cultured cell-derived extracellular matrices (ECM) are of special interest. We hereby hypothesized that a "bony matrix" containing mineralized, osteogenic ECM is a potential efficacious carrier of BMP-2 for promoting bone formation and, therefore, compared the efficacy of the decellularized ECM derived from osteogenic-differentiated human mesenchymal stem cells (hMSCs) to the one obtained from ECM from undifferentiated hMSCs.

Custom-made macroporous bioceramic implants based on triply-periodic minimal surfaces for bone defects in load-bearing sites.

The architectural features of synthetic bone grafts are key parameters for regulating cell functions and tissue formation for the successful repair of bone defects. In this regard, macroporous structures based on triply-periodic minimal surfaces (TPMS) are considered to have untapped potential. In the present study, custom-made implants based on a gyroid structure, with (GPRC) and without (GP) a cortical-like reinforcement, were specifically designed to fit an intended bone defect in rat femurs.

Effect of the Bone Morphogenetic Protein-2 Doses on the Osteogenic Potential of Human Multipotent Stromal Cells- Containing Tissue Engineered Constructs.

A strategy for improving the efficacy of stem cell-based bone tissue engineering (TE) constructs is to combine bone morphogenetic protein-2 (BMP-2) with multipotent stromal cells (MSC). Previous studies on the potential cooperative effect of BMP-2 with human multipotent stromal cells (hMSCs) on bone formation have, however, shown contradictory results likely due to the various and/or inappropriate BMP-2 doses. Our results provided evidence that the addition of BMP-2 at low dose only was beneficial to improve the osteogenic potential of hMSCs-containing TE constructs, whereas BMP-2 delivered at high dose overcame the advantage of combining this growth factor with hMSCs.

Traumatic leaflet injury: comparison of porcine leaflet self-expandable and bovine leaflet balloon-expandable prostheses.

Objectives: The main goal of this study was to compare the occurrence of post-deployment leaflet injury between prostheses made of porcine and bovine pericardium.

Methods: Two types of prostheses, self-expandable prostheses with porcine pericardial leaflet on one side and balloon-expandable prostheses with bovine pericardial leaflet on the other side, were used. In each group, crimped prostheses were compared with control non-crimped prostheses.

Osteogenic potential of adipogenic predifferentiated human bone marrow-derived multipotent stromal cells for bone tissue-engineering.

In the present study, we evaluated the benefits of an adipogenic predifferentiation, the pathway most closely related to osteoblastogenesis, on the pro-osteogenic potential of human adult multipotent bone marrow stromal cells (hBMSCs), both in vitro and in vivo. Adipogenic differentiation of hBMSCs for 14 days resulted in a heterogeneous cell population from which the most adipogenic-committed cells were eliminated by their lack of readhesion ability. Our results provided evidence that the select adherent adipogenic differentiated hBMSCs (sAD+ cells) express a gene profile characteristic of both adipogenic and osteogenic lineages.