Research advances in cartilage stem cells markers and induced differentiation / 华西口腔医学杂志

Cartilage stem cells (CSCs) are cells that self-proliferate, have surface antigen expression, and have multidirectional differentiation potential in the articular cartilage. CSCs, as an ideal source of stem cells, has a good application prospect in stem cell therapy. This article reviews the CSCs markers, cartilage differentiation signaling pathway, and clinical treatment of osteoarthritis.

Role of ATP6V1H gene in bone metabolism / 中国骨伤

Osteoporosis is one of the common clinical orthopedic diseases, which can lead to a variety of complications. There are many pathogenic factors in this disease. The latest research found that ATP6V1H is a new gene leading to the occurrence of osteoporosis, and it is likely to become a new target for the future drug treatment of osteoporosis.This paper introduces the biological structure and characteristics of H subunit, summed up the human body caused by loss of ATP6V1H and animal models such as zebrafish, mice bone loss and osteoporosis symptom such as related research reports of the loss, from osteoclast, osteoblast and marrow stromal cell level and the connection between the various subunits further expounds the H subunit regulate bone dynamic balance of mechanism, to explore ATP6V1H in bone developmentand bone related diseases has laid a solid foundation, also provide new ideas for clinical treatment of osteoporosis.

Effect of hydrostatic pressure on ultrastructure of synovial fibroblasts from rat temporomandibular joint / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the role of apoptosis in the remodeling of temporomandibular joint (TMJ) under pressure.</p><p><b>METHODS</b>Synovial fibroblasts obtained from rat temporomandibular joint were subjected to different hydrostatic pressure for 12 h. Changes of ultrastructure were observed by transmission electron microscope.</p><p><b>RESULTS</b>At 30 kPa, the ultrastructure of synovial fibroblasts showed no obvious changes. At 60 kPa, the chromatin was condensated, the baryon took on crescent and the mitochondria seemed varicose. At 90 kPa, the apoptosis-like body was wrapped by membrane and embedded in the high density chromatin.</p><p><b>CONCLUSIONS</b>Apoptosis-like change took place in ultrastructure of synovial fibroblasts under hydrostatic pressure, and the degree of the change was related to the hydrostatic pressure exerted.</p>

Expression of BMP/Smads in rabbit condylar cartilage during mandibular forward positioning / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To identify the relationship between the expression of BMP/Smads in condylar cartilage and condylar growth modifications in rabbits during mandibular forward positioning.</p><p><b>METHODS</b>Sixty male rabbits with 8 weeks of age were randomly divided into the experimental group (n=36) and control group (n=24). The mandibles of rabbits in the experimental groups were induced to forward position by a functional appliance. The rabbits in the experimental group and control group were sacrificed after 3 days and 1, 2, 4, 8, 12 weeks, respectively. The expression of BMP-2, Smad1/5, 4 and 6 in condylar cartilage was examined by immunohistochemical staining.</p><p><b>RESULT</b>The expression of BMP-2, Smad1/5, 4 and 6 was mainly found in the chondrocytes from the transitional zone and hypertrophic zone, and was also found in the chondrocytes and osteoblasts of the mineralized zone. Compared with those of the age-matched controls, the positive signals for BMP-2, Smad1/5, 4 and 6 in the experimental animals were stronger at early stage (P<0.05), coinciding with the remodeling in condylar cartilage after functional appliance.</p><p><b>CONCLUSION</b>The expression of BMP-2, Smad1/5, 4 and 6 is associated with the adaptive remodeling of the condylar cartilage after functional appliance.</p>

Gene expression changes of cartilage matrix of condylar cartilage with anterior disc displacement / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the gene expression changes in extracellular matrix of condylar cartilage following disc anterior displacement of rabbit TMJ.</p><p><b>METHODS</b>The right sides of 28 joints in 40 rabbits were subjected to surgical operation of disc displacement. The condylar Collagen II and Aggrecan mRNA expression were detected by in situ hybridization.</p><p><b>RESULTS</b>Collagen II and Aggrecan mRNA mainly expressed in the lower zone of condylar chondrocyte. Aggrecan mRNA decreased faster than collagen II following disc displacement, and adjusted to normal later.</p><p><b>CONCLUSION</b>Anterior disc displacement leads to alteration of extracellurar matrix gene expression in the condylar chondrocyte, which means the start of remodeling.</p>

Disc-like changes and type II collagen mRNA expression in the bilaminar zone of rabbit temporomandibular joint following disc displacement / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the adaptive alteration in bilaminar zone of rabbits' temporomandibular joint following disc displacement.</p><p><b>METHODS</b>Twenty-six Japanese white rabbits were used in this study. Among these rabbits,6 were used as controls. The right discs of other 20 rabbits were displaced anteriorly by operation. Four of these rabbits were killedatn 1, 2, 4, 6 and 8 weeks respectively after surgery. The TMJS were studied by HE staining, Alcin bluen staining and in situ detection of type II collagen mRNA expression.</p><p><b>RESULTS</b>There appeared cartilage metaplasia after one week following disc displacement. Typical chondrocytes could be found in the bilaminar zone. The new chondrocytes expressed type II collagen.</p><p><b>CONCLUSIONS</b>The bilaminar zone of TMJ will be remodeled following disc displacement and become a disc-like tissue to function as a disc.</p>