Objective To evaluate the effect of left atrial enlargement on atrial myocardial fibrosis degree and levels of the angiotensinⅡ (AngⅡ)/Rac GTPase activating protein 1 (Rac1)/signal transducersand activators of transcription 3 (STAT3) signaling pathways expressing in patients with persistent atrial fibrillation and rheumatic heart disease (RHD). Methods From March to December 2011, 30 patients with RHD who underwent prosthetic valve replacement in our hospital were enrolled, including 16 males and 14 females, aged 42-70 (56.9±6.8) years. Twenty RHD patients with persistent atrial fibrillation as a research group and ten RHD patients with sinus rhythm as a control group (group A) underwent transthoracic echocardiography and right atrial appendage (RAA) tissue samples were obtained from these patients during mitral/aortic valve replacement operation. The research group according to left atrial diameter (LAD) was divided into two groups, ten patients in each group: a group B with LAD of 50–65 mm and a group C with LAD of LAD>65 mm. For each sample, histological examination was performed by hematoxylin-eosin and Masson’s trichrome staining. Light-microscopic pictures of atrial tissues samples were stained and tissue fibrosis degree in each group was analyzed. AngⅡ concentration was measured by enzyme linked immunosorbent assay. Rac1 and STAT3 were measured by western blotting. Results LAD was significantly greater in AF patients with RHD than in the control group. Hematoxylin-eosin staining demonstrated highly organized arrangement of atrial muscles in the control group and significant derangement in both group B and group C with reduced cell density and increased cell size. Moreover, Masson’s trichrome staining showed that atrial myocytes were surrounded by large trunks of collagen fibers in both group B and group C, but not in the group A. There was a positive correlation between atrial tissue fibrosis and LAD. AngⅡ content was positively correlated with LAD. Similarly, Rac1 and STAT3 protein levels were found considerably higher in the group C and group B than in the group A with excellent correlation to LAD. Conclusion In patients with RHD complicated with persistent atrial fibrillation, the degree of atrial fibrosis and the expression level of AngⅡ/Rac1/STAT3 signaling pathways significantly increase with the left atrialenlargement.
ObjectiveTo investigate the mid-term effectiveness of three‐dimensional (3D) printed osteotomy guide plate and personalized prosthesis in knee‐preserving tumor resection. Methods The clinical data of 12 patients who underwent knee‐preserving tumor resection and reconstruction with 3D printed osteotomy guide plate and personalized prosthesis between September 2016 and October 2018 were retrospectively analyzed. There were 7 males and 5 females. The age ranged from 7 to 59 years, with a median of 44.5 years. There were 11 cases of osteosarcoma and 1 case of fibrosarcoma, all of which were Enneking grade ⅡB. The distance from the tumor to the joint surface was 5.5-8.2 cm, with an average of 6.94 cm. Incision healing, tumor recurrence, periprosthetic fracture, and aseptic loosening were observed after operation. The Musculoskeletal Tumor Society (MSTS) scoring system was used to evaluate the function of the patients, and the knee flexion range of motion was measured. ResultsThe 12 patients were followed up 41-66 months, with an average of 54.5 months. The length of osteotomy ranged from 14 to 26 cm, with an average of 22.08 cm. Except for 2 patients with superficial infection of incision tissue, no deep infection involving the prosthesis occurred, no patient underwent revision surgery because of prosthesis infection. During the follow-up, local recurrence occurred in 2 cases and distant metastasis occurred in 3 cases. The overall disease-free survival rate was 58.3%. Two patients died of lung metastasis, and the overall survival rate was 83.3%. One patient underwent amputation due to local recurrence, and 1 patient underwent total knee arthroplasty due to prosthesis rupture. No aseptic loosening of the prosthesis and periprosthetic fracture occurred during the follow-up, and the overall prosthesis survival rate was 83.3%. At last follow-up, 10 patients obtained satisfactory knee flexion range of motion that ranged from 95° to 125°, with an average of 110°. Two children could not cooperate with early rehabilitation treatment due to pain, and the knee flexion range of motion was not ideal (50°, 75°). All patients achieved acceptable lower limb function with MSTS scores ranged from 26 to 30, with an average of 28. All patients walked without crutches. ConclusionThe treatment of malignant bone tumors around the knee joint with 3D printed osteotomy guide plate and personalized prosthesis can preserve the articular surface, obtain good limb function, reduce the risk of aseptic loosening of prosthesis, and achieve better mid-term effectiveness.