Bone implant outcome and bone regeneration properties can be improved by the immunomodulation of exosomes (Exos) derived from bone marrow mesenchymal stem cells (BMSCs), which contain cytokines, signaling lipids, and regulatory miRNAs. Analysis of miRNAs in BMSCsderived exosomes showed that miR-21a-5p exhibited the highest expression and was associated with the NF-κB pathway. Hence, we developed an implant with miR-21a-5p functionality to promote bone incorporation by immunoregulation. Mediated by the potent interaction between tannic acid (TA) and biomacromolecules, the tannic acid modified mesoporous bioactive glass nanoparticles coated with miR-21a-5p

It is well-established that treating articular cartilage injuries is clinically challenging since they lack blood arteries, nerves, and lymphoid tissue. Recent studies have revealed that bone marrow stem cell-derived exosomes (BMSCs-Exos) exert significant chondroprotective effects through paracrine secretions, and hydrogel-based materials can synergize the exosomes through sustained release. Therefore, this research aims to synthesize an ECM (extracellular matrix)-mimicking gelatin methacryloyl (GelMA) hydrogel modified by gelatin combined with BMSCs-derived exosomes to repair cartilage damage. We first isolated and characterized exosomes from BMSCs supernatant and then loaded the exosomes into GelMA hydrogel to investigate cartilage repair effects in in vitro and in vivo experiments. The outcomes showed that the GelMA hydrogel has good biocompatibility with a 3D (three-dimensional) porous structure, exhibiting good carrier characteristics for exosomes. Furthermore, BMSCs-Exos had a significant effect on promoting chondrocyte ECM production and chondrocyte proliferation, and the GelMA hydrogel could enhance this effect through a sustained-release effect. Similarly, in vivo experiments showed that GelMA-Exos promoted cartilage regeneration in rat joint defects and the synthesis of related cartilage matrix proteins.

Background Hip arthroplasty (HA) is one of the most effective procedures for patients with hip fractures. The timing of surgery played a significant role in the short-term outcome for these patients, but conflicting evidence has been found. Methods The Nationwide Inpatient Sample database was investigated from 2002 to 2014 and identified 247,377 patients with hip fractures undergoing HA. The sample was stratified into ultra-early (0 day), early (1–2 days) and delayed (3–14 days) groups based on time to surgery. Yearly trends, postoperative surgical and medical complications, postoperative length of hospital stay (POS) and total costs were compared after propensity scores were matched between groups by demographics and comorbidity. Results From 2002 to 2014, the percentage of hip fracture patients who underwent HA increased from 30.61 to 31.98%. Early surgery groups showed fewer medical complications but higher surgical complications. However, specific complication evaluation showed both ultra-early and early groups decreased most of the surgery and medical complications with increasing post hemorrhagic anemia and fever. Medical complications were also reduced in the ultra-early group, but surgical complications increased. Early surgery groups reduced the POS by 0.90 to 1.05 days and total hospital charges by 32.6 to 44.9 percent than delayed surgery groups. Ultra-early surgery showed no benefit from POS than early group, but reduced total hospital charges by 12.2 percent. Conclusion HA surgery performed within 2 days showed more beneficial effects on adverse events than delayed surgery. But surgeons should be cognizant of the potential increased risks of mechanical complications and post-hemorrhagic anemia.