ABSTRACT
The anterior disc displacement (ADD) leads to temporomandibular joint osteoarthritis (TMJOA) and mandibular growth retardation in adolescents. To investigate the potential functional role of fibrocartilage stem cells (FCSCs) during the process, a surgical ADD-TMJOA mouse model was established. From 1 week after model generation, ADD mice exhibited aggravated mandibular growth retardation with osteoarthritis (OA)-like joint cartilage degeneration, manifesting with impaired chondrogenic differentiation and loss of subchondral bone homeostasis. Lineage tracing using Gli1-CreER+; Tmfl/-mice and Sox9-CreER+;Tmfl/-mice showed that ADD interfered with the chondrogenic capacity of Gli1+ FCSCs as well as osteogenic differentiation of Sox9+ lineage, mainly in the middle zone of TMJ cartilage. Then, a surgically induced disc reposition (DR) mouse model was generated. The inhibited FCSCs capacity was significantly alleviated by DR treatment in ADD mice. And both the ADD mice and adolescent ADD patients had significantly relieved OA phenotype and improved condylar growth after DR treatment. In conclusion, ADD-TMJOA leads to impaired chondrogenic progenitor capacity and osteogenesis differentiation of FCSCs lineage, resulting in cartilage degeneration and loss of subchondral bone homeostasis, finally causing TMJ growth retardation. DR at an early stage could significantly alleviate cartilage degeneration and restore TMJ cartilage growth potential.
Subject(s)
Animals , Mice , Osteogenesis , Zinc Finger Protein GLI1 , Fibrocartilage , Temporomandibular Joint , Disease Models, Animal , Osteoarthritis , Stem Cells , Growth DisordersABSTRACT
BACKGROUND:Bone marrow mesenchymal stem cel s are considered to have good proliferation and differentiation potentials. Sox9 is a transcription factor that is essential for chondrogenesis and has been termed as a“master regulator”of the chondrocyte phenotype. OBJECTIVE:To study the therapeutic effects of Sox9-transfected bone marrow mesenchymal stem cel s on knee osteoarthritis. METHODS:The bone marrow mesenchymal stem cel s were transfected with Lenti-Sox9-EGFP in vitro. The model of murine knee osteoarthritis was established by cutting off the anterior cruciate ligament. Thirty model mice were randomly divided into three groups, as normal saline group, bone mesenchymal stem cel group and Sox9-transfected bone mesenchymal stem cel group. 0.1 mL of normal saline, 0.1 mL of normal saline containing non-transfected bone marrow mesenchymal cel s (non-transfected group), or 0.1 mL of normal saline containing Sox9-transfected bone marrow mesenchymal cel s (Sox9-transfected group) was injected into the knee joint cavity of mice in the corresponding group, respectively. After 4, 8, 12 weeks, the repair of articular cartilage lesions was evaluated by toluidine blue and immunohistochemical staining. RESULTS AND CONCLUSION:The lesions of articular cartilage were more serious in the normal saline group, compared with the other two groups, and the difference became more obvious over time. Damaged articular cartilage was improved in the non-transfected group, but the improvement was less than that in the Sox9-transfected group. Immunohistochemistry staining revealed that in the Sox9-transfected group, the positive type II col agen expression was stronger than that in the other two groups, but this positive expression was decreased over time in al the three groups. These results suggest that Sox9-transfected bone marrow mesenchymal stem cel s promote the repair of damaged cartilage in mice with knee osteoarthritis.
ABSTRACT
Objective:To establish a rapid, sensitive and accurate HPLC-QTOF/MS determination method for the illegally added antihypertensive drugs in traditional Chinese medicines and healthy care products .Methods:An Agilent Eclipse plus C 18 column ( 50 mm ×2.1 mm,1.8 μm) was adopted with the mobile phase of 0.5%formic acid and acetonitrile with gradient elution .The flow rate was 0.2 ml· min-1 .The electrospray ionization source was applied and operated in a positive ion mode .Results:The detection limit of 18 antihypertensive drugs was within the range of 0.2-2.5 ng· ml-1 .Reserpine was found in one sample .Conclusion:The method is selective and sensitive , which can be used for the detection of 18 chemical medicines illegally added in antihypertensive traditional Chinese medicines and health care products .
ABSTRACT
Objective:To improve the determination method for the residual solvents in olsalazine sodium. Methods:1,2-Dichlo-roethane and chloroform were determined by headspace GC with a DB-624 capillary column and an FID detector. The column tempera-ture was 110℃. The temperature of the injector and the detector was 200℃ and 250℃, respectively. The carrier gas was nitrogen with a flow of 3. 0 ml·min-1 . The split ratio was 1∶1. Water was used as the solvent. Results:1,2-Dichloroethane and chloroform were completely separated with good linearity within the respective range of 0. 25-2. 52 ( r =0. 999 5 ) and 2. 28-22. 84 μg · ml-1 ( r =0. 999 5). The average recoveries were 98. 4% and 99. 5% with RSD of 1. 14% and 0. 98%(n=9), respectively. The detection lim-it were 0. 02 and 0. 06 μg·ml-1 , respectively. Conclusion:The method is rapid, sensitive and accurate, which can be used in the determination of residual organic solvents in olsalazine sodium.