Graphene-modified CePO4 nanorods effectively treat breast cancer-induced bone metastases and regulate macrophage polarization to improve osteo-inductive ability.

Background: Breast cancer bone metastasis has become one of the most common complications; however, it may cause cancer recurrence and bone nonunion, as well as local bone defects.

Methods: Herein, In vitro, we verified the effect of bioscaffold materials on cell proliferation and apoptosis through a CCK8 trial, staining of live/dead cells, and flow cytometry. We used immunofluorescence technology and flow cytometry to verify whether bioscaffold materials regulate macrophage polarization, and we used ALP staining, alizarin red staining and PCR to verify whether bioscaffold material promotes bone regeneration.

The Recombinant Protein EphB4-Fc Changes the Ti Particle-Mediated Imbalance of OPG/RANKL via EphrinB2/EphB4 Signaling Pathway and Inhibits the Release of Proinflammatory Factors In Vivo.

Aseptic loosening caused by wear particles is one of the common complications after total hip arthroplasty. We investigated the effect of the recombinant protein ephB4-Fc (erythropoietin-producing human hepatocellular receptor 4) on wear particle-mediated inflammatory response. In vitro, ephrinB2 expression was analyzed using siRNA-NFATc1 (nuclear factor of activated T-cells 1) and siRNA-c-Fos.

Bone Marrow Mesenchymal Stem Cell-Derived Exosomes Improves Spinal Cord Function After Injury in Rats by Activating Autophagy.

Background: Spinal cord injury (SCI) is a global medical problem. The smallest membrane-bound nanovesicles, known as exosomes, have a role in complex intercellular communication systems and can be used directly as therapeutic agents by acting as important paracrine factors. Nevertheless, the use of exosomes derived from BMSCs (BMSC-Exos) to treat SCI has been less, and the specific mechanism has not yet been reported.

Quercetin inhibits macrophage polarization through the p-38α/β signalling pathway and regulates OPG/RANKL balance in a mouse skull model.

Aseptic loosening caused by wear particles is a common complication after total hip arthroplasty. We investigated the effect of the quercetin on wear particle-mediated macrophage polarization, inflammatory response and osteolysis. In vitro, we verified that Ti particles promoted the differentiation of RAW264.

Impaired Autophagy in the Fibroblasts by Titanium Particles Increased the Release of CX3CL1 and Promoted the Chemotactic Migration of Monocytes.

Aseptic loosening (AL) is the most frequent cause of failure of total hip arthroplasties (THA). Prosthetic wear particle-induced monocyte recruitment to the periprosthetic tissue and subsequent inflammatory response are thought to be the major contribution to AL. Fibroblast is a dominant cell type in interfacial membrane (IFM) which is the main pathological feature of periprosthetic osteolysis in failed THAs.

Changes in Alignment of Ipsilateral Knee on Computed Tomography after Total Hip Arthroplasty for Developmental Dysplasia of the Hip.

Objective: To assess the changes in alignment of ipsilateral knee joint after total hip arthroplasty (THA) for patients with developmental dysplasia of the hip (DDH).

Methods: Thirty-four patients with DDH (38 hips) who underwent THA between February and December 2008 were included in the study: 4 men and 30 women with a mean age of 56.2 years.

Ursolic acid loaded-mesoporous bioglass/chitosan porous scaffolds as drug delivery system for bone regeneration.

Bioglass scaffolds have great application potentials in orthopedics, and Ursolic acid (UA) can effectively promote in vivo new bone formation. Herein, we for the first time developed the mesoporous bioglass/chitosan porous scaffolds loaded with UA (MBG/CS/UA) for enhanced bone regeneration. The MBG microspheres with particle sizes of ~300 nm and pore sizes of ~3.

Titanium particle‑mediated osteoclastogenesis may be attenuated via bidirectional ephrin‑B2/eph‑B4 signaling in vitro.

The present study investigated the role of bidirectional ephrin‑B2/erythropoietin‑producing human hepatocellular receptor 4 (ephB4) signaling in the regulation of wear particle‑mediated osteoclastogenesis in vitro. Mouse bone marrow macrophages (BMMs) were induced into osteoclasts by receptor activator of nuclear factor‑κB ligand (RANKL, 50 ng/ml). EphB4‑Fc, an osteoblast membrane surface receptor (4 µg/ml), was used to stimulate the ephrin‑B2 ligand of osteoclasts in the presence and absence of titanium (Ti).

Dynamic Alterations in Microarchitecture, Mineralization and Mechanical Property of Subchondral Bone in Rat Medial Meniscal Tear Model of Osteoarthritis.

Background: The properties of subchondral bone influence the integrity of articular cartilage in the pathogenesis of osteoarthritis (OA). However, the characteristics of subchondral bone alterations remain unresolved. The present study aimed to observe the dynamic alterations in the microarchitecture, mineralization, and mechanical properties of subchondral bone during the progression of OA.

Calcineurin/NFAT pathway mediates wear particle-induced TNF-α release and osteoclastogenesis from mice bone marrow macrophages in vitro.

Aim: To investigate the roles of the calcineurin/nuclear factor of activated T cells (NFAT) pathway in regulation of wear particles-induced cytokine release and osteoclastogenesis from mouse bone marrow macrophages in vitro.

Methods: Osteoclasts were induced from mouse bone marrow macrophages (BMMs) in the presence of 100 ng/mL receptor activator of NF-κB ligand (RANKL). Acridine orange staining and MTT assay were used to detect the cell viability.

Strontium ranelate reduces cartilage degeneration and subchondral bone remodeling in rat osteoarthritis model.

Aim: To investigate whether strontium ranelate (SR), a new antiosteoporotic agent, could attenuate cartilage degeneration and subchondral bone remodeling in osteoarthritis (OA).

Methods: Medial meniscal tear (MMT) operation was performed in adult SD rats to induce OA. SR (625 or 1800 mg·kg(-1)·d(-1)) was administered via gavage for 3 or 6 weeks.

Efficacy of zoledronic acid in treatment of teoarthritis is dependent on the disease progression stage in rat medial meniscal tear model.

Aim: To investigate whether the stage of osteoarthritis (OA) progression influenced the efficacy of the third-generation bisphosphonate zoledronic acid in a rat medial meniscal tear model.

Methods: Medial meniscal tear (MMT) was surgically induced in adult male Sprague Dawley rats. Zoledronic acid (ZOL, 100 μg/kg, sc, twice a week) was administered starting immediately, early (from 4 weeks) or late (from 8 weeks) after OA induction.

Effect of impaction on gene-modified cells seeded on granular bone allografts in vitro and in vivo.

Background: While attempting to restore bone stock, impaction bone grafting employed during revision joint surgery may result in slow and limited allograft incorporation into host bone. A new approach including gene-modified bone marrow stromal cells (BMSCs) in combination with impaction bone grafting may effectively restore bone stock and improve allograft incorporation. This study aimed to investigate the effect of impaction on gene-modified BMSCs seeded on granular bone allografts in vitro and in vivo.

[The effect of ultra high molecular weight polyethylene particles on macrophage].

Objective: To study the effect of ultra high molecular weight polyethylene (UHMWPE) particles on macrophages and evaluate the expression of NFAT2, a key transcriptional factor for osteoclast differentiation.

Methods: From November 2004 to February 2005, macrophages were co-cultured with UHMWPE particles. When observed at different times, the proliferation activity of macrophages was analyzed by MTT and the expression of calcineurin (CaN) and NFAT2 by immunohistochemical and RT-PCR method respectively.

In vitro study of knee stability after two-band two-tunnel posterior cruciate ligament reconstruction.

Objective: To compare the ability of three different reconstruction procedures in restoring the posterior displacement of tibia and the posterior stability of the knee joint from 0 degree to 120 degrees flexion.

Methods: Three posterior cruciate ligaments (PCL) reconstruction procedures were performed, namely two-band two-tunnel reconstruction, one-band anterior tunnel reconstruction and one-band posterior tunnel reconstruction. The posterior displacement of the tibia in relation to the femur was measured when a 200N posterior force was applied.