Cobalt-Doped Mesoporous Silica Coated Magnetic Nanoparticles Promoting Accelerated Bone Healing in Distraction Osteogenesis.

Introduction: Large bone abnormalities are commonly treated using distraction osteogenesis (DO), but it is not suitable for a long-term application; therefore, there is an urgent need for adjuvant therapy that can accelerate bone repair.

Methods: We have synthesized mesoporous silica-coated magnetic nanoparticles doped with cobalt ions (Co-MMSNs) and assessed their capacity to quicken bone regrowth in a mouse model of DO. Furthermore, local injection of the Co-MMSNs significantly accelerated bone healing in DO, as demonstrated by X-ray imaging, micro-CT, mechanical tests, histological evaluation, and immunochemical analysis.

Distal Ulnar Bifurcation Arthroplasty in the Treatment of Bayne and Klug Types 3 and 4 Radial Club Hands: Preliminary Outcomes.

Background: The treatment of Bayne and Klug types 3 and 4 radial club hands (RCHs) remains challenging and controversial. In this study, the authors reported a new procedure called distal ulnar bifurcation arthroplasty and reviewed the preliminary results.

Methods: Between 2015 and 2019, 11 patients with 15 affected forearms having type 3 or 4 RCHs underwent distal ulnar bifurcation arthroplasty.

Real-time wear monitoring of hob cutter based on statistical analysis.

Real-time wear monitoring of hob cutters is of great significance to the quality and efficiency of gear hobbing. To achieve this goal, a strategy based on statistical analysis is proposed in this paper. First, vibration signals during the entire life cycle of a hob cutter are collected.

Free extended posterior tibial artery perforator flap with the neurovascular plexus of a saphenous nerve branch for large soft tissue and sensory reconstruction: Anatomic study and clinical application.

Background: The posterior tibial artery perforator (PTAP) flap is a useful tool for reconstruction of soft tissue defects in the leg. However, the size and reliability of the flap largely depends on the quality of the perforator by which the flap is supplied, and the sensory recovery of the flap is limited. In this study, the anatomy of the saphenous nerve branches and their accompanying vessels was investigated, and a free extended PTAP flap with the neurovascular plexus of a saphenous nerve branch was designed for large soft tissue and sensory reconstruction in a series of clinical cases.

Docosahexaenoic Acid Improves Diabetic Wound Healing in a Rat Model by Restoring Impaired Plasticity of Macrophage Progenitor Cells.

Background: Chronic inflammation associated with delayed diabetic wound healing is induced by disturbed polarization of macrophages derived mainly from predisposed progenitor cells in bone marrow. Docosahexaenoic acid plays a critical role in regulating the function of macrophage progenitor cells. The authors evaluated whether docosahexaenoic acid accelerates diabetic wound healing in rats.

Exosomes Secreted by Young Mesenchymal Stem Cells Promote New Bone Formation During Distraction Osteogenesis in Older Rats.

Distraction osteogenesis (DO) is a clinically effective procedure to regenerate large bone defects. However, the treatment duration is undesirably lengthy, especially in elderly patients. Exosomes derived from mesenchymal stem cells (MSC-Exos) could exert the beneficial effects while avoiding the possible complications of stem cell transplantation.

Regeneration of large bone defects using mesoporous silica coated magnetic nanoparticles during distraction osteogenesis.

Distraction osteogenesis (DO) represents an effective but undesirably lengthy treatment for large bone defects. Both magnetic nanoparticles and silicon have been shown to induce osteogenic differentiation of mesenchymal stem cells (MSCs), the key participant in bone regeneration. We herein synthesized mesoporous silica coated magnetic (FeO) nanoparticles (M-MSNs) and evaluated its potential for acceleration of bone regeneration in a rat DO model.

Von Hippel-Lindau (VHL) Protein Antagonist VH298 Improves Wound Healing in Streptozotocin-Induced Hyperglycaemic Rats by Activating Hypoxia-Inducible Factor- (HIF-) 1 Signalling.

Aims: The purpose of the present research is to investigate the effects of the VHL protein antagonist, VH298, on functional activities of fibroblasts and vascular endothelial cells and the effects on the wound healing process in a streptozotocin-induced hyperglycaemic rat model.

Methods: HIF-1 and hydroxy-HIF-1 protein levels in VH298-treated rat fibroblasts (rFb) were measured by immunoblotting, rFb proliferation was detected by the CCK-8 assay, and mRNA levels of related genes were measured by quantitative RT-PCR. In vitro wound healing was simulated by the scratch test; angiogenesis was measured by the human umbilical vein endothelial cell (hUVEC) tube formation assay.

Roxadustat promotes angiogenesis through HIF-1α/VEGF/VEGFR2 signaling and accelerates cutaneous wound healing in diabetic rats.

Diabetic foot ulcers are a major health-care burden worldwide. One primary cause of the delayed wound healing in diabetic patients is impaired function of the hypoxia-inducible factor-1α/vascular endothelial growth factor (HIF-1α/VEGF) axis, which results in compromised neovascularization in response to hypoxia. In the present study, we aimed to investigate the effect of roxadustat, a novel HIF prolyl-4-hydroxylase inhibitor, on angiogenesis and its therapeutic effect on cutaneous wound healing in diabetic rats.

Impaired Bone Regenerative Effect of Exosomes Derived from Bone Marrow Mesenchymal Stem Cells in Type 1 Diabetes.

Stem cell-derived exosomes have exhibited promise for applications in tissue regeneration. However, one major problem for stem cell-derived exosome therapies is identifying appropriate source cells. In the present study, we aimed to compare the bone regenerative effect of exosomes secreted by bone marrow mesenchymal stem cells (BMSCs) derived from type 1 diabetes rats (dBMSC-exos) and exosomes secreted by BMSCs derived from normal rats (nBMSC-exos).

Catalpol promotes the osteogenic differentiation of bone marrow mesenchymal stem cells via the Wnt/β-catenin pathway.

Background: Rehmanniae Radix is a traditional herbal medicine in East Asia that has been widely used to treat patients with osteoporosis. However, the effect of catalpol, the primary active principle component of Rehmanniae Radix, on the function of bone marrow mesenchymal stem cells (BMSCs) and the underlying molecular mechanisms associated with its activity remain poorly understood.

Methods: The effect of catalpol on the proliferation of BMSCs was evaluated using a Cell Counting Kit-8 assay.

All-Trans Retinoic Acid Promotes Osteogenic Differentiation and Bone Consolidation in a Rat Distraction Osteogenesis Model.

Distraction osteogenesis (DO) is used to treat specific disorders associated with growth abnormalities and/or loss of bone stock secondary to trauma or disease. However, a high rate of complications and discomfort hamper its further application in clinical practice. Here, we investigated the effects of all-trans retinoic acid (ATRA) on osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (rBMSCs) and bone consolidation in a rat DO model.

Exosomes secreted by endothelial progenitor cells accelerate bone regeneration during distraction osteogenesis by stimulating angiogenesis.

Background: Distraction osteogenesis (DO) is an effective but lengthy procedure to fully induce bone regeneration in large bone defects. Accumulating evidence supports the role of exosomes secreted by endothelial progenitor cells (EPC-Exos) in stimulating angiogenesis, which is closely coupled with osteogenesis. This study aimed to investigate whether EPC-Exos promote bone regeneration during DO in rats.

Nanofiber arrangement regulates peripheral nerve regeneration through differential modulation of macrophage phenotypes.

Topographical cues presented by aligned nanofibers have been demonstrated to stimulate peripheral nerve regeneration across long gaps, but the underlying mechanisms remain incompletely elucidated. Because macrophages play a crucial role in peripheral nerve regeneration and can be phenotypically modulated by topographical cues, we hypothesized that aligned nanofibers might induce the development of macrophage phenotypes that facilitate the regeneration of peripheral nerves. Here, macrophages were seeded on aligned and random poly(l-lactic acid-co-ε-caprolactone) nanofibers and their morphology and phenotypes were compared.

Von Hippel-Lindau (VHL) protein antagonist, VH298, promotes functional activities of tendon-derived stem cells and accelerates healing of entheses in rats by inhibiting ubiquitination of hydroxy-HIF-1α.

Enthesis is the region where a tendon attaches to a bone. It is a relatively vulnerable position, and in most cases surgical treatment is required upon rupture. The reconstructed enthesis is usually weaker compared to the original, and is prone to rupture again.

All-trans retinoic acid improves the viability of ischemic skin flaps in diabetic rat models.

Aims: Endothelial progenitor cells (EPCs) play a critical role in neovascularization, which enhances proliferation under all-trans retinoic acid (ATRA) treatment. However, the effects of ATRA on the skin flap survival in diabetic flap ischemia remains unknown.

Methods: Ischemic random skin flaps were made in 40 diabetic Sprague-Dawley rats with 20 normal rats used as control in this study.

Silk fibroin enhances peripheral nerve regeneration by improving vascularization within nerve conduits.

Silk fibroin (SF)-based nerve conduits have been widely used to bridge peripheral nerve defects. Our previous study showed that nerve regeneration in a SF-blended poly (l-lactide-co-ɛ-caprolactone) [P(LLA-CL)] nerve conduit is better than that in a P(LLA-CL) conduit. However, the involved mechanisms remain unclarified.

A novel duplication downstream of BMP2 in a Chinese family with Brachydactyly type A2 (BDA2).

Background: Brachydactyly type A2 (BDA2) is an autosomal dominant disease characterized by the deformation of the middle phalanx of the second fingers and toes. It has been reported to be associated with three genes regulating the osteogenesis, including BMPR1B, GDF5 and BMP2.

Materials And Methods: 10 BDA2 patients and 7 unaffected individuals in a Chinese family were identified through clinical signs and radiographs.

The Effect of Atorvastatin on the Viability of Ischemic Skin Flaps in Diabetic Rats.

Background: Endothelial progenitor cells play a critical role in neovascularization. However, the mobilization, recruitment, and functional capacity of endothelial progenitor cells are significantly impaired in diabetes. Statins have been shown to augment the number and improve the function of endothelial progenitor cells.

Stimulation of Nitric Oxide Production Contributes to the Antithrombotic Effect of Stromal Cell-Derived Factor-1α in Preventing Microsurgical Anastomotic Thrombosis.

Background Intimal injury plays a critical role in initiating the pathogenesis of thrombosis formation after microsurgical anastomosis. Application of stromal cell-derived factor-1α (SDF-1α) is reported to promote early regeneration of injured intima through migration of endothelial cells and mobilization of endothelial progenitor cells. We therefore hypothesized that local transfer of SDF-1α gene would inhibit microsurgical anastomotic thrombosis.

Reverse-Flow Lateral Tarsal Island Flap for Covering the Great Toe Donor Site of Wraparound Flap.

Background: Coverage of the great toe donor site of wraparound flap remains a challenge. This report presents the results of using an innervated pedicled reverse-flow lateral tarsal island flap for covering the great toe donor site of wraparound flap.

Patients And Methods: Between 2005 and 2010, 11 reverse-flow lateral tarsal island flaps were used to cover the great toe donor site of wraparound flap in 11 patients.

Combined Anterolateral Thigh and Anteromedial Thigh Flap for Extensive Extremity Reconstruction: Vascular Anatomy and Clinical Application.

Background: The combined anterolateral thigh (ALT) and anteromedial thigh (AMT) flap has been previously reported for use in complicated head and neck reconstruction. However, it has not gained popularity due to the vascular variation. Here, we explore the vascular basis of this combined flap, and report its application in extremity reconstruction.

Management of hypertrophic nonunion with failure of internal fixation by distraction osteogenesis.

Introduction And Aim: Distraction osteogenesis is employed in the management of hypertrophic nonunion associated with angular deformity and shortening. This study was aimed at evaluating the outcomes of Ilizarov apparatus without bone graft or open osteotomy in cases of hypertrophic nonunion not responding to treatment with internal fixation.

Methods: We retrospectively reviewed the data of 12 patients (mean age, 46.