Surface Properties and MC3T3-E1 Cell Response of Cortical Bone Allografts Modified with Low-Concentration Phosphoric Acid

Background/Aims: This experimental study aimed to evaluate the effect of low-concentration phosphoric acid on the surface structure of cortical allografts. Methods: Allogenic cortical bones were obtained from femurs and tibias of New Zealand white rabbits. The bones were modified by treatment with various concentrations of phosphoric acid (10%, 20% or 30%) for 10, 30 or 60 minutes, then evaluated by the following methods: 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and LIVE/DEAD assay, alkaline phosphatase (ALP) assay, biomechanical properties testing, contact angle detection, quantitative real-time polymerase chain reaction (Q-PCR), western blotting and scanning electron microscopy (SEM). Results: Compared with the other groups, the group modified with 10% H3PO4 for 10 minutes had lower cytotoxicity according to MTT and LIVE/DEAD assays, higher hydrophilicity in the contact angle detection test and greater stability in the biomechanical properties test. Moreover, an up-regulation of osteopontin (OPN) in bones modified with 10% H3PO4 was observed by Q-PCR and western blotting. In addition, ALP assay and SEM showed that surface porosity and osteoinductivity were increased in the group modified with 10% H3PO4. Conclusions: Low-concentration phosphoric acid may be a potential method for surface modification of cortical allografts. Further animal experiments and animal infection model studies are required to validate the efficacy of surface-modified cortical allografts to repair large segmental bone defects

Icariin Protects against Glucocorticoid-Induced Osteonecrosis of the Femoral Head in Rats

Background/Aims: Glucocorticoid (GC)-related osteonecrosis of the femoral head (ONFH) is a common complication following administration of steroids to treat many diseases. Our previous study demonstrated that icariin (ICA) might have a beneficial effect on the bone marrow mesenchymal stem cells (BMSCs) of patients with steroid-associated osteonecrosis. In this study, we investigated the underlying mechanisms of ICA associated with the potential enhancement of osteogenesis and anti-adipogenesis in GC-related ONFH. Methods: In vitro cell proliferation was evaluated by CCK-8 assay. Alizarin red S and alkaline phosphatase (ALP) activity were used to measure osteogenic differentiation, while adipogenic differentiation was revealed by oil red O staining and TG content assay. The expression level of osteogenesis-associated genes and PPARγ was evaluated by RT-qPCR, western blotting and immunofluorescence. A total of 30 female SD rats were randomly separated into three groups: a control group, a methylprednisolone (MPS) group and a MPS + ICA group. Serum ALP and TG (triglyceride), micro-CT scanning, histological and immunohistochemical analyses were performed in the animal model. Results: In the in vitro study, ICA promoted proliferation, improved osteogenic differentiation and suppressed adipogenic differentiation of BMSCs treated with MPS. The group treated with MPS and 10-6 M ICA expressed higher levels of Runx2, ALP, bone morphogenetic protein (BMP) 2, and OC and lower expression of PPARγ than the MPS group. In the in vivo study, ICA prevented bone loss in a rat model of GC-related ONFH as shown by micro-CT scanning, histological and immunohistochemical analyses. Conclusions: ICA is an effective compound for promoting bone repair and preventing or delaying the progression of GC-associated ONFH in rats. This effect can be explained by its ability to improve the balance between adipogenesis and osteogenesis, indicating that ICA is an effective candidate for management of GC-associated ONFH

Comparison of prognostic value between CAD-RADS 1.0 and CAD-RADS 2.0 evaluated by convolutional neural networks based CCTA

Objectives: The aim of the present study was to investigate the prognostic value of the novel coronary artery disease reporting and data system (CAD-RADS) 2.0 compared with CAD-RADS 1.0 in patients with suspectedcoronary artery disease (CAD) evaluated by convolutional neural networks (CNN) based coronary computed tomography angiography (CCTA). Methods: A total of 1796 consecutive inpatients with suspected CAD were evaluated by CCTA for CAD-RADS 1.0 and CAD-RADS 2.0 classifications. Kaplan-Meier and multivariate Cox models were used to estimate major adverse cardiovascular events (MACE) inclusive of all-cause mortality or myocardial infarction (MI). The C-statistic was used to assess the discriminatory ability of the two classifications. Results: In total, 94 (5.2%) MACE occurred over the median follow-up of 45.25 months (interquartile range 43.53–46.63 months). The annualized MACE rate was 0.014 (95% CI: 0.011–0.017). Kaplan-Meier survival curves indicated that the CAD-RADS classification, segment involvement score (SIS) grade, and Computed Tomography Fractional Flow Reserve (CT-FFR) classification were all significantly associated with the increase in the cumulative MACE (all P < 0.001). CAD-RADS classification, SIS grade, and CT-FFR classification were significantly associated with endpoint in univariate and multivariate Cox analysis. CAD-RADS 2.0 showed a further incremental increase in the prognostic value in predicting MACE (c-statistic 0.702, 95% CI: 0.641–0.763, P = 0.047), compared with CAD-RADS 1.0. Conclusions: The novel CAD-RADS 2.0 evaluated by CNN-based CCTA showed higher prognostic value of MACE than CAD-RADS 1.0 in patients with suspected CAD