Expression of epidermal growth factor receptor in human periodontal ligament cells during their mineralization in vitro / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression of epidermal growth factor receptor (EGFR) during the mineralization of human periodontal ligament cells (hPDLC) in vitro.</p><p><b>METHODS</b>Studies using specific antibodies to immunolocalize EGFR in the mineral differentiating hPDLC were undertaken to investigate the different expression during the inducing process. In situ hybridization and RT-PCR technique were used to investigate the transcripts encoding the protein of EGFR.</p><p><b>RESULTS</b>The results showed that immunocytochemical labeling gradually decreased following the elong of the induce time, downing to nearly negative at the 4th week and the signal of EGFR transcripts was weaker in the induced hPDLC than that in uninduced.</p><p><b>CONCLUSION</b>EGFR has a negative regulation function during the mineralization of hPDLC.</p>

Expression of core binding factor a1, bone morphogenetic proteins and osteopontin in the developing periodontal tissues of mice / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the expression and interaction of core binding factor a1 (Cbfa1), bone morphogenetic proteins (BMPs) and osteopontin (OPN) in the developing periodontal tissues of mice.</p><p><b>METHODS</b>A mice developing periodontal tissues study model was created histologically by 5-27 day postnatal BALB/c mice, then the immunohistochemical localization of Cbfa1, BMPs and OPN in different developing stages were undertaken.</p><p><b>RESULTS</b>In early stage of postnatal mice periodontal tissues development, only BMPs expressed in dental follicle cells, though the signal was weak. When root was forming, all of them were expressed in periodontal ligament cells and cementoblasts, while only OPN in acellular cementum, cellular cementum and the surface of alveolar bone, Cbfa1 only in cellular cementum and BMPs was seen in neither acellular cementum nor cellular cementum.</p><p><b>CONCLUSION</b>Cbfa1, BMPs and OPN all involve in the development of periodontal tissues, while OPN is crucial for cementum.</p>

Immunohistochemical localization of leucine-rich proteoglycans in the developing periodontal tissues of mice / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the distribution and expression of fibromodulin, decorin and biglycan in developing normal periodontal tissues, so as to understand its role in periodontal tissue formation.</p><p><b>METHODS</b>Thirty six BALB/c mice in different developing stages were killed and their bilateral mandibular first molars with surrounding alveolar bones and gingival tissues were taken out, Power Vision two steps immunohistochemical method with anti-fibromodulin, anti-decorin and anti-biglycan was used to detect the tissue distribution and cellular localization of fibromodulin and related proteoglycans, decorin and biglycan.</p><p><b>RESULTS</b>Fibromodulin was strongly expressed in the subcutaneous gingival connective tissue, periodontal ligament, mainly in gingival and periodontal fibroblasts as well as their matrices. Strong expression was also noted in the area close to the interfaces of periodontal ligament-alveolar bone and periodontal ligament-cementum. Decorin was strongly expressed in the area of gingival connective tissue, periodontal ligament and the surface of alveolar bone, while biglycan was stained evidently in gingival connective tissue throughout the period of investigation, but negative in the surface of alveolar bone and osteoblasts.</p><p><b>CONCLUSIONS</b>Fibromodulin may interact with decorin and biglycan to regulate the network formation of gingival connective tissues and periodontal collagen fibers, and may be involved in mineralization of the alveolar bone and cementum.</p>

Expression of Runx2/Cbfa1 in the developing pulpo-dentinal complex of postnatal mice / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the expression of Runx2/Cbfa1 in the developing dentin and differentiating odontoblasts.</p><p><b>METHODS</b>A postnatal mice teeth developing model was built histologically. Immunohistochemical technique was adopted to determine the expression of Runx2/Cbfa1 in the developing pulpo-dentinal complex in mice.</p><p><b>RESULTS</b>Runx2/Cbfa1 was merely present in predentin in the exact and before the 11th day's postnatal stages. Meanwhile, it was positively located in odontoblasts and dental pulp cells in root region, but negatively in coral part after the 11th day's stages.</p><p><b>CONCLUSION</b>Runx2/Cbfa1 may play an important role in the deposing of tooth dentin and in the differentiating of odontoblasts and pulp cells.</p>