Steroid-induced avascular necrosis of the femoral head (SANFH) is the death of the femoral head caused by long-term use of glucocorticoid (GC). Its pathological manifestations are mainly trabecular bone collapse and increased empty bone lacunas, osteocyte apoptosis rate and autophagy rate. Its pathogenesis is complicated, and the exact pathogenesis is still unclear. MicroRNAs (miRNAs) are a group of endogenous, non-coding small RNAs with an average length of 23 nucleotides. They are responsible for negatively regulating gene expression after transcription by inhibiting target messenger RNAs (mRNAs). MiRNAs play an important role in physiological processes, including cell development, proliferation, differentiation, metabolism, migration and apoptosis. According to bioinformatics analysis, MiRNAs play an important role in regulating gene expression, and it is estimated that more than one-third of human genes are regulated by them. In the past few years, more and more miRNAs have been found to be related to osteonecrosis, such as regulating the proliferation and differentiation of mesenchymal stem cells and osteoblasts. This article aims to review the relationship between steroid-induced femoral head necrosis and miRNAs.

Objective:To qualitatively analyze the elasticity characteristics of boundaries and surrounding liver tissue of focal liver lesions (FLL) by real-time shear wave elastography (SWE), and to analyze the relating influencing factors.Methods:One hundred and fifty-two patients with FLLs (152 lesions) from February 2012 to October 2013 in the First Affiliated Hospital of Sun Yat-Sen University were collected. SWE of FLLs and the surrounding liver tissue was performed and baseline clinical data were collected. The elastic boundary (clear or not clear) of FLLs and elasticity distributions of surrounding liver tissue and their influencing factors were analyzed.Results:A total of 26 benign lesions and 126 malignant lesions were included in this study. Twenty-five cases (96.2%) of benign lesions showed clear elastic boundaries and 1 case (3.8%) showed unclear elastic boundary while 82 cases (65.1%) of malignant lesions showed clear elastic boundaries and 44 cases (34.9%) showed unclear elastic boundaries. Multivariate analysis showed benign/malignant lesion was an independent influencing factor for elastic boundary ( P<0.05). Twenty cases (76.9%), 6 cases (23.1%) and 0 case of liver tissue around benign lesions showed type A, B and C elastic distribution respectively while 17 cases (13.5%), 60 cases (47.6%), and 49 cases (38.9%) of liver tissue around malignant lesions showed type A, B, and C elastic distribution. There were statistically significant differences of benign and malignant lesions, different viral hepatitis backgrounds, different gender, and different ALB, TBIL, ALT levels in elasticity distributions of surrounding liver tissue of FLLs among type A, B and C (all P<0.05) while there was no significant difference in different lesion size( P=0.036). Conclusions:The elasticity characteristics of boundaries and surrounding liver tissue of FLLs on SWE images can provide a reference for differential diagnosis of benign and malignant FLLs. The elastic characteristics of surrounding liver tissue of FLLs are influenced by the nature of lesions and the background of liver disease, but are not influenced by lesion size. Further quantitative studies of elasticity characteristics of boundaries and surrounding liver tissue are needed for the differential diagnosis of different types of FLLs.

Objective:To establish a model based on two-dimensional shear wave elastography (2D-SWE) for predicting post-hepatectomy liver failure (PHLF) among patients with hepatocellular carcinoma (HCC).Methods:One hundred and one consecutive patients with HCC undergoing hepatectomy from August 2018 to July 2019 were enrolled prospectively in the First Affiliated Hospital of Sun Yat-Sen University. Laboratory tests, shear wave elastography in liver parenchyma, and abdominal contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) were performed preoperatively. Liver functional reserve, liver stiffness (LS), and tumor-related imaging parameters were assessed. PHLF was defined according to the definition of International Study Group of Liver Surgery Recommendations (ISGLS). A predictive model was developed by logistic regression analysis and the performance thereof was evaluated by receiver operating characteristic (ROC) curve analysis and Hosmer-Lemeshow test.Results:PHLF occurred in 39 patients (38.9%). Logistic regression analysis identified that international normalized ratio ( OR=1.09, P=0.026), LS( OR=1.297, P=0.004) and the largest nodule diameter( OR=1.191, P=0.015) were independent risk factors of PHLF.The area under curve (AUC) of the model was 0.842(95% CI =0.763-0.921), which was significantly higher than those of ALBI score, MELD score and Child-Pugh score (AUC 0.626-0.688, P<0.05). The model also showed good calibration in Hosmer-Lemeshow test ( P=0.498). Conclusions:A model based on 2D-SWE provides good preoperative prediction of PHLF among patients with HCC, which might have the potential in better customizing treatment strategy in those patients.