BACKGROUND:Osteoarthritis,often accompanied by cartilage abnormal signal transduction,suggesting that intracellular signal transduction may play an important role in osteoarthritis genesis and development.OBJECTIVE:To review recent advances in the research of Notch signaling pathway,and explore the mechanisms of chondrogenic differentiation of bone marrow mesenchymal stem cells and its role in cartilage development and chondrogenesis.To analysis the role of dysregulated Notch signaling in the development of osteoarthritis.METHODS:Pubmed was undertaken to identify the relevant articles published from March 1919 to February 2009 with the key words of"Notch signaling pathway,osteoarthritis,chondrocytes,chondrogenesis,bone marrow stem cells"in English.Simultaneously,CNKI Database was searched for relevant articles published from February 2004 to September 2008 with the key words of"Notch signaling pathway,osteoarthritis,chondrocytes,chondrogenesis,bone marrow stem cells"in Chinese Articles with the Notch signaling pathway-related research,Notch signaling pathway of bone marrow-derived mesenchymal stem cells,differentiation of cartilage relative to the mechanism studies,and the Notch signaling pathway disorders and osteoarthritis research were included,Reproducibility articles were excluded Development regulation of articular cartilage and cartilage cell proliferation were considered as evaluation indexes.RESULTS AND CONCLUSION:Of 632 articles retrieved,30 were included in our study according to the inclusive and exclusive criteria.The Notch pathway is a highly consewed signaling mechanism involved in many processes determining cell fate during development and maintenance of homeostasis of mature tissues in the adult organism.Activation of Notch occurs following Notch receptor/ligand engagement upon cell-cell contact,which initiates translocation of the Notch intracellular domain to the nucleus and activation of target genes.It has been demonstrated that the Notch signaling plays an important role in regulating articular cartilage development and chondrocyte proliferation and differentiation In recent studies abnormality of notch signaling was also found in disease,which suggests that notch signaling is involved in osteoarthritis initiation and development.Further study of the specific mechanism of notch signaling in the initiation and development of osteoarthritis will enable us to develop targeted approaches in the treatment of osteoarthritis,thus bring more strategies in the future treatment of osteoarthritis.

Objective:To introduce a 2-stage treatment protocol for the management of temporomandibular joint ankylosis with sec-ondary deformities in adults.Methods:24 adult patients (9 males and 15 female)(30 joints)at the average age of 26.1 years un-derwent TMJ reconstruction as the initial surgery,followed by orthodontic treatment and correction of secondary deformities as the sec-ond surgery.Clinical outcome was assessed based on maximal incisal opening,radiography and medical photography.Results:Skele-tal deformities were significantly improved in all patients,satisfactory occlusion was achieved with the orthodontic treatment,average maximal incisal opening increased from 3.4 mm to 32.5 mm(P <0.05).Conclusion:The 2-stage treatment protocol is an effective approach for management of TMJ ankylosis with secondary deformities in adult patients.

OBJECTIVEThis work investigated mesenchymal stem cells (MSCs) modified with Runt-related transcription factor 2 (Runx2) therapy for bone regeneration in rabbit mandibular distraction osteogenesis.

METHODSForty-eight New Zealand mature white rabbits were randomly divided into three groups after the rabbit model of mandibular distraction osteogenesis was established: reconstruction plasmid modified with Runx2 (group A), plasmid without Runx2 (group B), and the same dose of saline as control (group C). At the fifth day of distraction phase, MSCs with reconstruction plasmid modified with adv-hRunx2-gfp were injected into the distraction gap of group A. MSCs with reconstruction plasmid modified with adv-gfp was injected into the distraction gap of group B, whereas group C was injected with the same dose of saline. At 8 weeks after injection, all animals were sacrificed, and the distracted mandibles were harvested. The general imaging histological observation and three-point bending test were used for evaluation.

RESULTSCT plain scan and histological analysis confirmed that the amount of new bone forming in the distraction gap of group A was significantly higher than those in groups B and C. Dual-energy X ray and three-point bending test results also showed that the bone mineral density, bone mineral content, and maximum load of the distraction gap of group A were significantly higher than those of groups B and C (P<0.01).

CONCLUSIONRunx2-ex vivo gene therapy based on MSCs can effectively promote the bone regeneration in rabbit mandibular distraction osteogenesis and shorten the stationary phase. Therefore, reconstruction of craniofacial fracture would be a valuable strategy

Absorptiometry, Photon ; Animals ; Bone Density ; Bone Regeneration ; physiology ; Core Binding Factor Alpha 1 Subunit ; genetics ; pharmacology ; Genetic Therapy ; Mandible ; physiology ; surgery ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stromal Cells ; Osteogenesis ; genetics ; Osteogenesis, Distraction ; methods ; Plasmids ; Rabbits ; Random Allocation ; Transcription Factors ; genetics ; physiology ; Treatment Outcome

BACKGROUND:During the healing of fractures, removal of sciatic nerve can result in insufficient mechanical rigidity of newborn woven bone. However, there are less reports concerning the denervation effects during distraction osteogenesis. OBJECTIVE:To observe the effect of removal of the sciatic nerve on bone regeneration and the expression of Runt-related transcription factor 2 (Runx2) protein during distraction osteogenesis in a rabbit model. METHODS:Twenty-four adult male New Zealand rabbits were selected and underwent left tibial osteodistraction to construct animal models of distraction osteogenesis. Before distraction, the animals were randomly divided into group R (resecting the left sciatic nerve) and group I (intact left sciatic nerve). Six weeks after completion of distraction, the animals were kil ed and the lengthened tibias were harvested for radiography, three-dimensional CT reconstruction, histological evaluation, connectivity density (Conn.D) evaluation. RESULTS AND CONCLUSION:New regenerated bone was present and Runx2 protein was expressed in the distraction gaps of al animals at the end of the study, as revealed by radiography, three-dimensional CT reconstruction, and histological observation. However, less new bone formation and a lower degree of mineralization and expression of Runx2 protein were observed in group R compared with group I. The results suggest that the denervation appears to have an inhibitory effect on bone formation and the expression of Runx2 protein during distraction osteogenesis.

OBJECTIVE To establish the fingerprints of c ultivated and wild Anemarrhena asphodeloides，and to identify their differential components. METHODS Using an evaporative light-scattering detector ， the high performance liquid chromatography combined with Similarity Evaluation System of TCM Chromatographic Fingerprint （2012 edition） were used to establish fingerprints of 14 batches of cultivated A. asphodeloides and 14 batches of wild medicinal materials ，and evaluate their similarity. The common peaks were identified by comparison with the chromatogram of the mixed control. At the same time ，the contents of components corresponding to common peaks in cultivated and wild A. asphodeloides were determined. The principal component analysis and orthogonal partial least squares discrimination analysis were adopted to identify differential components of them ，and compare the contents of them. RESULTS Among 28 batches of A. asphodeloides ，10 common peaks were found ，i.e. neomangiferin（peak 1），mangiferin（peak 2），isomangiferin（peak 3），timosaponin B Ⅱ（peak 7），timosaponin B Ⅲ（peak 8）， timosaponin Ⅰ（peak 9），timosaponin A Ⅲ（peak 10）. The similarities of fingerprints of samples with control fingerprint were no less than 0.963. The average total contents of seven components in cultivated and wild A. asphodeloides were 74.18 and 84.72 mg/g， respectively；there was statistical significance （P＜0.05）. The cultivated and wild A. asphodeloides could be divided into two categories. The differential components were neomangiferin ，mangiferin，timosaponin B Ⅱ and timosaponin A Ⅲ（VIP values were all higher than 1）. The content of neomangiferin in cultivated products was significantly higher than that in wild products （P＜ 0.05），and the contents of mangiferin ，timosaponin B Ⅱ and ti mosaponin A Ⅲ were significantly lower than those in wild products （P＜0.05）. CONCLUSIONS Fingerprint of A. asphodeloides is established ，and differential components of cultivated and wild A. asphodeloides are identified primarily.