A New Insight of Kartogenin Induced the Mesenchymal Stem Cells (MSCs) Selectively Differentiate into Chondrocytes by Activating the Bone Morphogenetic Protein 7 (BMP-7)/Smad5 Pathway.

BACKGROUND Rotator cuff injury is the most common cause of shoulder disability, and although the repair technique has improved, the rate of rotator cuff reduction after repair is still high. The fibrocartilage region, which appears to be histologically inserted, cannot be regenerated. In recent years, studies have reported that mesenchymal stem cells (MSCs) have enhanced cartilage regeneration in the tendon and bone interface after rotator cuff repair, which has become a hot topic of research. MATERIAL AND METHODS Two mesenchymal stem cell types, SMSC (synovial-derived mesenchymal stem cells) and BMSC (bone marrow-derived mesenchymal stem cells) were intervened using kartogenin (KGN). The cytotoxicity was evaluated and the proliferation of the 2 cells was observed. Four commonly used cartilage phenotype genes were detected by quantitative real-time polymerase chain reaction, and the cartilage differentiation of MSCs induced by KGN was explored. The bidirectional regulation of the expression of BMP-7 and the downstream gene Smad5 was observed by constructing a lentiviral overexpression vector containing the target gene BMP-7. To explore whether BMP-7/Smad5 pathway activation promotes differentiation of SMSCs into chondrocytes. RESULTS KGN can induce the selective differentiation of endogenous MSCs into chondrocytes by activating the BMP-7/Smad5 pathway, which promotes the regeneration of interfacial cartilage, and improves the quality of tendon healing of the tendon after rotator cuff repair. CONCLUSIONS This study found a new biological intervention method to promote the effect of tendon on bone healing after rotator cuff repair.

C1 Titanium Cables Combined with C2 Pedicle Screw-Rod Fixation for Atlantoaxial Instability Not Suitable for Placement of C1 Screws.

OBJECTIVE: We sought to develop a new posterior fusion technique composed of bilateral C1 titanium cables and C2 pedicle screw-rods for treatment of atlantoaxial instability not suitable for C1 screw placement. METHODS: A study was conducted of 18 patients with atlantoaxial instability who had C1 broken screw trajectory or anatomic anomalies. All patients underwent posterior fixation with bilateral C1 titanium cables and C2 pedicle screws. The follow-up period was a minimum 1 year. Clinical outcomes measurements included visual analog scale score for neck pain assessment, the American Spinal Injury Association Impairment Scale and Japanese Orthopaedic Association score for neurologic status and function. According to preoperative computed tomography (CT) reconstruction and CT angiography, the patients selected in this study were not suitable for C1 screw placement. Postoperative plain radiographs and CT reconstruction were performed to evaluate the reduction, bony fusion, and implant position. All outcomes were evaluated at each follow-up. RESULTS: The average clinical follow-up period was 24 months (range 12-36 months). All patients had complete neck pain relief at postoperative 6 months. Their neurologic symptoms had improved significantly at 1-year follow-up. Radiologic outcomes indicated good bony fusion and construction stability in all patients without implant failure at the last follow-up. No neural or vascular complications related to this technique were observed. CONCLUSIONS: Posterior atlantoaxial fixation using C1 titanium cables and C2 pedicle screw-rod construct appears to be an effective and safe technique for treatment of atlantoaxial instability, which could be an alternative method for cases unsuitable for C1 screw placement when using C1-C2 screw fixation.

[Contents comparision of atractylode I, II, III in rhizoma atractylodis macrocephalae and the processed with soils].

OBJECTIVE: To research the effect of processing with soils on the contents of Atractylode I, II, III of Rhizoma Atractylodis Macrocephalae. METHODS: Contents of Atractylode I, II, III were determined by HPLC. Hypersil-ODS C18 (200 mm x 4.6 mm, 5 microm) column was used; The mobile phase consisted of acetonitrile-water; The flow rate was 1.0 mL/min; The detection wavelength was 220 nm and 276 nm,the column temperature was 30 degrees C. RESULTS: All the indexes of Atractylode I, II, III peak were qualified; The result of methodological study was met the requirement of HPLC; The average contents of Atractylode I , II , II in raw Rhizoma Atractylodis Macrocephalae were 0.4365, 0.2878, 0.4140 mg/g, the soil-processed Rhizoma Atractylodis Macrocephalae were 0.5503, 0.3013, 0.8403 mg/g, the processed Rhizoma Atractylodis Macrocephalae were 0.5386, 0.2958, 0.7399 mg/g. CONCLUSION: The content of Atractylode II is no significant difference among the raw Rhizoma Atractylodis Macrocephalae and the Processed. The contents of both Atractylode I and III increased after processed. However, there is no significant difference between the soil-processed and the processed Rhizoma Atractylodis Macrocephalae with nothing.