Vagus nerve stimulation was first used in the treatment of refractory epilepsy and depression, and its indications have expanded in recent years. The brain-gut axis is a bidirectional communication network pathway connecting the gut to the brain, maintaining homeostatic balance of the gut microbiota and shaping brain function. The vagus nerve plays an important role in brain-gut axis mechanisms in neurological disorders, which may be an important rationale for vagus nerve stimulation in the treatment of related diseases. Recent studies have shown that vagus nerve stimulation modulates the intestinal microenvironment and the intestinal microbiota, but the specific mechanisms of this alteration need further investigation. Fecal transplants or oral probiotics combined with vagus nerve stimulation may become an important therapeutic tool in the future, especially to improve the efficacy of vagus nerve stimulation for epilepsy; the gut microbiota may also be a predictive target for the efficacy of vagus nerve stimulation for epilepsy.
Objective To investigate whether the Runx2 gene can induce the differentiation of human amniotic mesenchymal stem cells (hAMSCs) to ligament fibroblasts in vitro and promote the tendon-bone healing in rabbits. Methods hAMSCs were isolated from the placentas voluntarily donated from healthy parturients and passaged, and then identified by flow cytometric identification. Adenoviral vectors carrying Runx2 gene (Ad-Runx2) and empty vector adenovirus (Ad-NC) were constructed and viral titer assay; then, the 3rd generation hAMSCs were transfected with Ad-Runx2 (Ad-Runx2 group) or Ad-NC (Ad-NC group). The real-time fluorescence quantitative PCR and Western blot were used to detect Runx2 gene and protein expression to verify the effectiveness of Ad-Runx2 transfection of hAMSCs; and at 3 and 7 days after transfection, real-time fluorescence quantitative PCR was further used to detect the expressions of ligament fibroblast-related genes [vascular endothelial growth factor (VEGF), collagen type Ⅰ, Fibronectin, and Tenascin-C]. The hAMSCs were used as a blank control group. The hAMSCs, hAMSCs transfected with Ad-NC, and hAMSCs were mixed with Matrigel according to the ratio of 1 : 1 and 1 : 2 to construct the cell-scaffold compound. Cell proliferation was detected by cell counting kit 8 (CCK-8) assay, and the corresponding cell-scaffold compound with better proliferation were taken for subsequent animal experiments. Twelve New Zealand white rabbits were randomly divided into 4 groups of sham operation group (Sham group), anterior cruciate ligament reconstruction group (ACLR group), anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-NC-scaffold compound group (Ad-NC group), and anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-Runx2-scaffold compound group (Ad-Runx2 group), with 3 rabbits in each group. After preparing the ACL reconstruction model, the Ad-NC group and the Ad-Runx2 group injected the optimal hAMSCs-Matrigel compunds into the bone channel correspondingly. The samples were taken for gross, histological (HE staining and sirius red staining), and immunofluorescence staining observation at 1 month after operation to evaluate the inflammatory cell infiltration as well as collagen and Tenascin-C content in the ligament tissues. ResultsFlow cytometric identification of the isolated cells conformed to the phenotypic characteristics of MSCs. The Runx2 gene was successfully transfected into hAMSCs. Compared with the Ad-NC group, the relative expressions of VEGF and collagen type Ⅰ genes in the Ad-Runx2 group significantly increased at 3 and 7 days after transfection (P<0.05), Fibronectin significantly increased at 3 days (P<0.05), and Tenascin-C significantly increased at 3 days and decreased at 7 days (P<0.05). CCK-8 detection showed that there was no significant difference (P>0.05) in the cell proliferation between groups and between different time points after mixed culture of two ratios. So the cell-scaffold compound constructed in the ratio of 1∶1 was selected for subsequent experiments. Animal experiments showed that at 1 month after operation, the continuity of the grafted tendon was complete in all groups; HE staining showed that the tissue repair in the Ad-Runx2 group was better and there were fewer inflammatory cells when compared with the ACLR group and the Ad-NC group; sirius red staining and immunofluorescence staining showed that the Ad-Runx2 group had more collagen typeⅠ and Ⅲ fibers, tending to form a normal ACL structure. However, the fluorescence intensity of Tenascin-C protein was weakening when compared to the ACLR and Ad-NC groups. Conclusion Runx2 gene transfection of hAMSCs induces directed differentiation to ligament fibroblasts and promotes tendon-bone healing in reconstructed anterior cruciate ligament in rabbits.
Objective To summarize mid-term effectiveness of modified arthroscopic suture button fixation Latarjet procedure for treatment of recurrent anterior shoulder dislocations. Methods Between January 2018 and October 2020, 30 patients with recurrent anterior shoulder dislocations were treated with modified arthroscopic suture button fixation Latarjet procedure. There were 19 males and 11 females with an average age of 27.3 years (range, 18-41 years). The shoulder dislocation occurred 3-7 times, with an average of 4.9 times. The time from the last dislocation to operation was 3-10 days, with an average of 4.1 days. Glenoid defects exceeded 20% in all cases. There were 27 cases of Hill-Sachs lesions. The joint pain and function were estimated by visual analogue scale (VAS) score, University of California, Los Angeles (UCLA) score, Rowe score, American Association for Shoulder and Elbow Surgery (ASES) score, Walch-Duplay score, and the range of external rotation at 0° and external rotation at 90° abduction of shoulder before operation and at 1 month, 6 months, and last follow-up. The X-ray film, CT scan and three-dimensional reconstruction were reviewed to observe the position, healing, and absorption of the coracoid graft, correction of glenoid defect, and joint degeneration.Results The operation time ranged from 51 to 79 minutes, with an average of 68.4 minutes. All incisions healed without complications such as nerve or blood vessel injury. All patients were followed up 36-60 months with an average of 44.6 months. The VAS score, UCLA score, Rowe score, ASES score, Walch-Duplay score, and the range of external rotation at 0° and external rotation at 90° abduction after operation significantly improved when compared with preoperative values (P<0.05). All indicators further improved with time, and the differences between different time points after operation were significant (P<0.05). Imaging review showed that the coracoid graft was located in the anteroinferior glenoid at 1 day after operation, and no occurrence of shoulder osteoarthritis was found during follow-up. The anatomical structure of the glenoid was normal, and no delayed healing or non-union of the coracoid graft occurred. At 20 months after operation, arthroscopic re-exploration was performed in 1 case due to fracutre caused by falling injury revealed the good shaping of the coracoid graft, smooth glenoid, and no bone resorption or osteoarthritis. ConclusionFor recurrent anterior shoulder dislocations, the modified arthroscopic suture button fixation Latarjet procedure can obtain good recovery of shoulder function and low incidence of complications and has a good mid-term effectiveness.