ABSTRACT
Objective To investigate biomechanical differences of two posterior occipitocervical internal fixation techniques for treating basilar invagination with atlantoaxial dislocation (BI-AAD). Methods Intra-articular cage + posterior occipital plate+C2 pedicle screw (Cage+C2PS+OP), and intra-articular cage+C1 lateral mass screw+C2PS (Cage+C1LMS+C2PS) models were established based on occipitocervical CT data of the BI-AAD and clinical operation scheme, and the stability of atlantoaxial joint and stress distribution characteristics of C2 endplate and implanted instruments under different motion states were analyzed. Results Compared with the Cage+C1LMS+C2PS model, the atlantoaxial range of motion ( ROM) under flexion, extension, lateral bending and axial rotation in the Cage+C2PS+OP model were reduced by 5. 26% , 33. 33% , 43. 75% , -5. 56% , and stress peak of screw-rod fixation system were reduced by 47. 81% , 60. 90% , 48. 45% , 39. 14% , respectively. Under two internal fixation modes, stresses of C2 endplate and cage were mainly distributed on the compressive side during the motion, and both the screw-bone interface and the caudal side of screw subjected to large loading. Conclusions Two internal fixation methods could provide similar stability. However, the stress concentration of screw-rod system was more obvious and the possibility of screw loosening and fracture was greater under Cage+ C1LMS+C2PS fixation.
ABSTRACT
Increasing attention is focused on the down-regulation of miRNAs in cancer process. Nuclear receptor subfamily 2 (NR2F2, also known as COUP-TFII) is involved in the development of many types of cancers, but its role in gastric cancer remains elusive. In this experiment, oncomine and Kaplan-meier database revealed that NR2F2 was up-regulated in gastric cancer and that the high NR2F2 expression contributed to poor survival. MicroRNA-27b was targeted and down-regulated by NR2F2 in human gastric cancer tissues and cells. The ectopic expression of miR-27b inhibited gastric cancer cell proliferation and tumor growth in vitro and in vivo. Assays suggested that the overexpression of miR-27b could promote MGC-803 cells' migration and invasion and retard their metastasis to the liver. In addition, down-regulation of miR-27b enhanced GES-1 cells' proliferation and metastasis in vitro. These findings reveal that miR-27b is a tumor suppressor in gastric cancer and a biomarker for improving patients' survival.
Subject(s)
Animals , Female , Humans , Male , Biomarkers, Tumor , Genetics , Metabolism , COUP Transcription Factor II , Genetics , Metabolism , Cell Line, Tumor , Genes, Tumor Suppressor , Heterografts , Mice, Nude , MicroRNAs , Genetics , Metabolism , Neoplasm Metastasis , Neoplasm Proteins , Genetics , Metabolism , Neoplasm Transplantation , RNA, Neoplasm , Genetics , Metabolism , Stomach Neoplasms , Genetics , Metabolism , PathologyABSTRACT
Objective To compare the feasibility and safety of endoscopy with laparoscopy and without for gastric stromal tumor.Methods A retrospective and comprehensive analysis was made based on the clinical data of endoscopic (53 cases) and laparoscopic (39 cases) resection for gastric stromal tumor (diameter ＜ 3 cm with clear boundary),by comparing the operation time,intraoperative blood loss,indwelling time of postoperative gastric tube,recovery time of bowel functions,postoperative complications,hospitalization time,metastasis,recurrence rate.Results Compared with the laparoscopic group,the endoscopic group required shorter operation time [50(48-58) min VS 70 (50-95) min,U =1575.00,P ＜ 0.01],less intraoperative blood loss [10 (5-15) ml VS 20 (20-30) ml,U =1794.00,P ＜ 0.01],earlier recovery of bowel functions [18 (8-36) h VS 24 (20-40) h,U =1666.00,P ＜ 0.01],hospitalization time,indwelling time of the postoperative gastric tube and postoperative complications showed no statistical difference (P ＞ 0.05).The postoperative follow-up time were (27 + 15) and (24 + 11) months in the endoscopic and laparoscopic group,respectively (t =0.3084,P ＞ 0.05).During the follow-up,no tumor recurrence or distant metastasis was discovered,nor was death of gastric stromal tumor.Conclusion Endoscopy without the assist of laparoscopy for the gastric stromal tumor,whose diameter is less than 3 cm with clear boundary,is safe and less invasive,and leads to quick recovery.