Preliminary outcomes of the combination of demineralized bone matrix and platelet Rich plasma in the treatment of long bone non-unions.

BACKGROUND: A variety of bone graft substitutes have been introduced into the treatment of bone non-unions. However, clinical outcomes from current evidences are various and conflicting. This study aimed to present the preliminary outcomes of a treatment protocol in which the combination of demineralized bone matrix (DBM) and platelet rich plasma (PRP) was used as a bone graft substitute for long bone non-unions. METHODS: Data of this retrospective study were reviewed and collected from a consecutive case series involving 43 patients who presented with a long bone non-union and were treated in our department from October 2018 to May 2019. The combination of DMB and PRP was applied as a bone defect filler in 16 patients, whilst the other 27 patients were treated with iliac bone autografting. Patients' demographics, postoperative complications and the result of bone union were compared and evaluated. RESULTS: The demographic data between the two groups were comparable. No significant difference was found with regard to the incidence of postoperative complications. No graft rejection, heterotopic ossification or other complications were noted. The distribution of bony healing time was rather scattered but did not differ significantly between the groups (7.533 ± 3.357 months vs. 6.625 ± 2.516 months; P=0.341). Union was identified radiographically in 15 of 16 patients in the DBM+PRP group and in 24 of 27 patients in autograft group. CONCLUSIONS: The present study identified that low incidence of postoperative complications and satisfactory bony healing rate could be achieved in the treatment of long bone non-unions augmented with the combination of DBM and PRP. Although these findings might indicate the promising future of this treatment protocol, larger and higher quality studies should also be executed to assess its routine use.

Stealth cationic liposomes modified with anti-CAGE single-chain fragment variable deliver recombinant methioninase for gastric carcinoma therapy.

Stealth cationic liposomes (SCLs) modified with tumor-targeting single-chain fragment variable (scFV) antibody for systemic delivery of recombinant methioninase (rMETase) for gastric cancer were prepared successfully. These functional SCL nanoparticles are composed of cationic lipids, dioleoylphosphatidylethanolamine, and distearoylphosphatidylethanolamine-polyethylene glycol, which have lower gene transfection efficiencies compared with Lipofectamine 2000, and can also be used as effective gene delivery vectors. Increased therapeutic efficiency of rMETase-loaded scFV-SCLs were tested in SGC-7901 cells and compared with free rMETase in solution and rMETase-loaded SCLs. In addition, scFV-SCLs (effective diameter: 185.7 nm; polydispersity index: 0.236) can significantly boost rhodamine 123 cellular accumulation in the cytoplasm. The scFV-targeted SCLs can be used as a potentially effective drug delivery system.

Three-dimensional poly (ε-caprolactone)/hydroxyapatite/collagen scaffolds incorporating bone marrow mesenchymal stem cells for the repair of bone defects.

We previously demonstrated that three-dimensional (3D) hydroxyapatite (HAP)-collagen (COL)-coated poly(ε-caprolactone) (PCL) scaffolds (HAP-COL-PCL) possess appropriate nano-structures, surface roughness, and nutrients, providing a favorable environment for osteogenesis. However, the effect of using 3D HAP-COL-PCL scaffolds incorporating BMSCs for the repair of bone defects in rats has been not evaluated. 3D PCL scaffolds coated with HAP, collagen or HAP/COL and incorporating BMSCs were implanted into calvarial defects. At 12 weeks after surgery, the rats were sacrificed and crania were harvested to assess the bone defect repair using microcomputed tomography (micro-CT), histology, immunohistochemistry and sequential fluorescent labeling analysis. 3D micro-CT reconstructed images and quantitative analysis showed that HAP-COL-PCL groups possessed better bone-forming capacity than HAP-PCL groups or COL-PCL groups. Fluorescent labeling analysis revealed the percentage of tetracycline labeling, alizarin red labeling, and calcein labeling in HAP-COL-PCL groups were all greater than in the other two groups (P < 0.05), and the result was confirmed by immunohistochemical staining and histological analysis of bone regeneration. This study demonstrates that 3D HAP-COL-PCL scaffolds incorporating BMSCs markedly enhance bone regeneration of bone defects in rats.