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Background and Objective: Bone tumors present significant challenges in orthopedic medicine due to variations in clinical treatment approaches for different tumor types, which includes benign, malignant, and intermediate cases. Convolutional Neural Networks (CNNs) have emerged as prominent models for tumor classification. However, their limited perception ability hinders the acquisition of global structural information, potentially affecting classification accuracy. To address this limitation, we propose an optimized deep learning algorithm for precise classification of diverse bone tumors. Materials and Methods: Our dataset comprises 786 computed tomography (CT) images of bone tumors, featuring sections from two distinct bone species, namely the tibia and femur. Sourced from The Second Affiliated Hospital of Fujian Medical University, the dataset was meticulously preprocessed with noise reduction techniques. We introduce a novel fusion model, VGG16-ViT, leveraging the advantages of the VGG-16 network and the Vision Transformer (ViT) model. Specifically, we select 27 features from the third layer of VGG-16 and input them into the Vision Transformer encoder for comprehensive training. Furthermore, we evaluate the impact of secondary migration using CT images from Xiangya Hospital for validation. Results: The proposed fusion model demonstrates notable improvements in classification performance. It effectively reduces the training time while achieving an impressive classification accuracy rate of 97.6%, marking a significant enhancement of 8% in sensitivity and specificity optimization. Furthermore, the investigation into secondary migration's effects on experimental outcomes across the three models reveals its potential to enhance system performance. Conclusion: Our novel VGG-16 and Vision Transformer joint network exhibits robust classification performance on bone tumor datasets. The integration of these models enables precise and efficient classification, accommodating the diverse characteristics of different bone tumor types. This advancement holds great significance for the early detection and prognosis of bone tumor patients in the future.

Summary: We carried out a meta-analysis on the effect of cardiac rehabilitation (CR) on cardiopulmonary function after coronary artery bypass grafting (CABG). Four databases were searched for studies comparing CR with control. A random-effects model was used to pool mean difference (MD). The meta-analysis showed an increase in peak oxygen consumption (peak VO2) (MD = 1.93 mL/kg/min, p = 0.0006), and 6-min walk distance (6MWD) (MD = 59.21 m, p

Reactive oxygen species (ROS) derived from NADPH oxidases (NOX) plays an essential role in advanced glycation end products (AGEs)-induced diabetic vascular endothelial dysfunction. Peroxidasin (PXDN, VPO1) is one member of peroxidases family that catalyzes hydrogen peroxide (H2O2) to hypochlorous acid (HOCl). This present study aimed to elucidate the role of PXDN in promoting vascular endothelial dysfunction induced by AGEs in diabetes mellitus. We found that, compared to non-diabetic (db/m) mice, PXDN expression was notably increased in db/db mice with impaired endothelium-dependent relaxation. Knockdown of PXDN in vivo through tail vein injection of siRNA restored the impaired endothelium-dependent relaxation function of db/db mice which is accompanied with up-regulation of eNOS Ser1177 phosphorylation and NO production. AGEs significantly elevated expression of PXDN and 3-Cl-Tyr, but decreased phosphorylation of Akt and eNOS and NO release in HUVECs. All these effects induced by AGEs were remarkable alleviated by silencing PXDN with small interfering RNAs. In addition, HOCl treatment alone as well as HOCl added with Akt inhibitor MK2206 inhibited phosphorylation of Akt and eNOS, reducing NO production. More importantly,AGEs-induced up-regulation of PXDN and 3-Cl-Tyr with endothelial dysfunction were transformed by NOX2 silencing and H2O2 scavengers. Thus, these results support the conclusion that PXDN promotes AGEs-induced diabetic vascular endothelial dysfunction by attenuating eNOS phosphorylation at Ser1177 via NOX2/HOCl/Akt pathway.

Vascular peroxidase 1 (VPO1) is a member of the peroxidase family which aggravates oxidative stress by producing hypochlorous acid (HOCl). Our previous study demonstrated that VPO1 plays a critical role in endothelial dysfunction through dimethylarginine dimethylaminohydrolase2 (DDAH2)/asymmetric Dimethylarginine (ADMA) pathway. Hereby we describe the regulatory role of VPO1 on endothelial nitric oxide synthase (eNOS) expression and activity in human umbilical vein endothelial cells (HUVECs). In HUVECs AngiotensinII (100 nM) treatment reduced Nitric Oxide (NO) production, decreased eNOS expression and activity, which were reversed by VPO1 siRNA. Knockdown of VPO1 also attenuated ADMA production and eNOS uncoupling while enhancing phosphorylated ser1177 eNOS expression level. Furthermore, HOCl stimulation was shown to directly induce ADMA production and eNOS uncoupling, decrease phosphorylated ser1177 eNOS expression. It also significantly suppressed eNOS expression and activity together with NO production. Therefore, VPO1 plays a vital role in regulating eNOS expression and activity via hydrogen peroxide (H2O2)-VPO1-HOCl pathway. Keywords: Vascular peroxidase 1, Endothelial nitric oxide synthase, Nitric oxide, Asymmetricdimethylarginine, Angiotensin II, Oxidative stress

Cardiac fibrosis is the most important mechanism contributing to cardiac remodeling after myocardial infarction (MI). VPO1 is a heme enzyme that uses hydrogen peroxide (H2O2) to produce hypochlorous acid (HOCl). Our previous study has demonstrated that VPO1 regulates myocardial ischemic reperfusion and renal fibrosis. We investigated the role of VPO1 in cardiac fibrosis after MI. The results showed that VPO1 expression was robustly upregulated in the failing human heart with ischemic cardiomyopathy and in a murine model of MI accompanied by severe cardiac fibrosis. Most importantly, knockdown of VPO1 by tail vein injection of VPO1 siRNA significantly reduced cardiac fibrosis and improved cardiac function and survival rate. In VPO1 knockdown mouse model and cardiac fibroblasts cultured with TGF-β1, VPO1 contributes to cardiac fibroblasts differentiation, migration, collagen I synthesis and proliferation. Mechanistically, the fibrotic effects following MI of VPO1 manifested partially through HOCl formation to activate Smad2/3 and ERK1/2. Thus, we conclude that VPO1 is a crucial regulator of cardiac fibrosis after MI by mediating HOCl/Smad2/3 and ERK1/2 signaling pathways, implying a promising therapeutic target in ischemic cardiomyopathy. Keywords: Cardiac fibrosis, Myocardial infarction, Vascular peroxidase1, Cardiac remodeling, Cardiac fibroblasts