The rising concerns of the recurrence and bone deficiency in surgical treatment of malignant bone tumors have raised an urgent need of the advance of multifunctional therapeutic platforms for efficient tumor therapy and bone regeneration. Herein, the construction of a multifunctional biomaterial system is reported by the integration of 2D Nb2C MXene wrapped with S‐nitrosothiol (RSNO)‐grafted mesoporous silica with 3D‐printing bioactive glass (BG) scaffolds (MBS). The near infrared (NIR)‐triggered photonic hyperthermia of MXene in the NIR‐II biowindow and precisely controlled nitric oxide (NO) release are coordinated for multitarget ablation of bone tumors to enhance localized osteosarcoma treatment. The in situ formed phosphorus and calcium components degraded from BG scaffold promote bone‐regeneration bioactivity, augmented by sufficient blood supply triggered by on‐demand NO release. The tunable NO generation plays a crucial role in sequential adjuvant tumor ablation, combinatory promotion of coupled vascularization, and bone regeneration. This study demonstrates a combinatory osteosarcoma ablation and a full osseous regeneration as enabled by the implantation of MBS. The design of multifunctional scaffolds with the specific features of controllable NO release, highly efficient photothermal conversion, and stimulatory bone regeneration provides an intriguing biomaterial platform for the diversified treatment of bone tumors.

In this study, an enzymatically cross-linked injectable and biodegradable hydrogel system comprising carboxymethyl pullulan-tyramine (CMP-TA) and chondroitin sulfate-tyramine (CS-TA) conjugates was successfully developed under physiological conditions in the presence of both horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) for cartilage tissue engineering (CTTE). The HRP crosslinking method makes this injectable system feasible, minimally invasive and easily translatable for regenerative medicine applications. The physicochemical properties of the mechanically stable hydrogel system can be modulated by varying the weight ratio and concentration of polymer as well as the concentrations of crosslinking reagents. Additionally, the cellular behaviour of porcine auricular chondrocytes encapsulated into CMP-TA/CS-TA hydrogels demonstrates that the hydrogel system has a good cyto-compatibility. Specifically, compared to the CMP-TA hydrogel, these CMP-TA/CS-TA composite hydrogels have enhanced cell proliferation and increased cartilaginous ECM deposition, which significantly facilitate chondrogenesis. Furthermore, histological analysis indicates that the hydrogel system exhibits acceptable tissue compatibility by using a mouse subcutaneous implantation model. Overall, the novel injectable pullulan/chondroitin sulfate composite hydrogels presented here are expected to be useful biomaterial scaffold for regenerating cartilage tissue.

Although systemic or local inflammation, commonly featured by cytokine activation, is implicated in patients with bone loss, the underlying mechanisms are still elusive. As microRNAs (miR), a class of small non-coding RNAs involved in essential physiological processes, have been found in bone cells, we aimed to investigate the role of miR for modulating osteogenesis in inflammatory milieu using human bone marrow mesenchymal stem cells (hBM-MSCs). Induced by proinflammatory cytokine TNF-α, miR-150-3p was identified as a key player in suppressing osteogenic differentiation through downregulating β-catenin, a transcriptional co-activator promoting bone formation. TNF-α treatment increased the levels of miR-150-3p, which directly targeted the 3′-UTR of β-catenin mRNA and in turn repressed its expression. In addition, we observed that miR-150-3p expression was increased by TNF-α via IKK-dependent NF-κB signalling. There are three putative NF-κB binding sites in the promoter region of miR-150, and we identified −686 region as the major NF-κB binding site for stimulation of miR-150 expression by TNF-α. Finally, the osteogenic differentiation of hBM-MSCs was inhibited by either miR-150-3p overexpression or TNF-α treatment, which was prevented by anti-miR-150-3p oligonucleotides. Taken together, our data suggested that miR-150-3p integrated inflammation signalling and osteogenic differentiation and may contribute to the inhibition effects of inflammation on bone formation, thus expanding the pathophysiological functions of microRNAs in bone diseases.

The failure of prosthesis after total joint replacement is mainly due to dysfunctional osseointegration and implant infection. There is a critical need for orthopedic implants that promote rapid osseointegration and prevent bacterial colonization, particularly when placed in bone compromised by disease or physiology of the patients. The aim of this study was to fabricate a novel coaxial electrospun polycaprolactone (PCL)/polyvinyl alcohol (PVA) core-sheath nanofiber (NF) blended with both hydroxyapatite nanorods (HA) and type I collagen (Col) (PCL(Col)/PVA(HA)). Doxycycline (Doxy) and dexamethasone (Dex) were successfully incorporated into the PCL(Col)/PVA(HA) NFs for controlled release. The morphology, surface hydrophilicity and mechanical properties of the PCL/PVA NF mats were analyzed by scanning electron microscopy, water contact angle and atomic force microscopy. The PCL(Col)/PVA(HA) NFs are biocompatible and enhance the adhesion and proliferation of murine pre-osteoblastic MC3T3 cells. The release of Doxy and Dex from coaxial PCL(Col)/PVA(HA) NFs showed more controlled release compared with the blended NFs. Using an ex vivo porcine bone implantation model we found that the PCL(Col)/PVA(HA) NFs bind firmly on the titanium rod surface and the NFs coating remained intact on the surface of titanium rods after pullout. No disruption or delamination was observed after the pullout test. These findings indicate that PCL(Col)/PVA(HA) NFs encapsulating drugs have great potential in enhancing implant osseointegration and preventing implant infection.

Implant-related infections (IRIs) which led to a large amount of medical expenditure were caused by bacteria and fungi that involve the implants in the operation or in ward. Traditional treatments of IRIs were comprised of repeated radical debridement, replacement of internal fixators, and intravenous antibiotics. It needed a long time and numbers of surgeries to cure, which meant a catastrophe to patients. So how to prevent it was more important than to cure it. As an excellent local release system, coating is a good idea by its local drug infusion and barrier effect on resisting biofilms which were the main cause of IRIs. So in this review, materials used for coatings and evidences of prevention were elaborated.

No abstract

Y chromosome abnormalities are frequently associated with male infertility. Men with ring Y chromosomes can present with sexual infantilism, ambiguous genitalia, hypospadias, or azoospermia. AZF microdeletions can result in spermatogenic defects in such patients. Here, we report an unusual karyotype of 45,X/46,X,r(Y)/46,X,dic r(Y) in an azoospermic man. However, the reason for this patient's azoospermia is not an AZF microdeletion but might be the abnormal structure of the r(Y) chromosome, the 45,X cell line, mosaicism of the 3 cell lines, or another unknown cause. In such cases, if the couple wishes to reproduce, cytogenetic, molecular and fluorescent in situ hybridization evaluations should be performed, and preimplantation genetic diagnosis should be used together with assisted reproductive technology.

Microglia, the major immune cells in central nervous system, act as the surveillance and scavenger of immune defense and inflammatory response. Previous studies suggest that there might be close relationship between acid-sensing ion channels (ASICs) and inflammation, however, the exact role of ASICs in microglia during inflammation remains elusive. In the present study, we identified the existence of ASICs in the primary cultured rat microglia and explored their functions. By using reverse transcriptase polymerase chain reaction (RT-PCR), quantitative real-time PCR (qPCR), western blotting, and immunofluorescence experiments, we demonstrated that ASIC1, ASIC2a, and ASIC3 were existed in cultured and in situ rat microglia. After lipopolysaccharide (LPS) stimulation, the expressions of microglial ASIC1 and ASIC2a were upregulated. Meanwhile, ASIC-like currents and acid-induced elevation of intracellular calcium were increased, which could be inhibited by the nonspecific ASICs antagonist amiloride and specific homomeric ASIC1a blocker PcTx1. In addition, both inhibitors reduced the expression of inflammatory cytokines, including inducible nitric oxide synthase and cyclooxygenase 2 stimulated by LPS. Furthermore, we also observed significant increase in the expression of ASIC1 and ASIC2a in scrape-stimulated microglial migration. Amiloride and PcTx1 prevented the migration by inhibiting ERK phosphorylation. Taken together, these results suggest that ASICs participate in neuroinflammatory response, which will provide a novel therapeutic strategy for controlling the inflammation-relevant neuronal diseases.