[A retrospective study on mandibular coracoid fractures].

OBJECTIVE: This study aimed to analyze the treatment for mandibular coracoid fractures retrospectively. METHODS: A retrospective study on 37 patients with mandibular coracoid fractures treated at Department of Traumatic and Plastic Surgery, West China Hospital of Stomatology, Sichuan University from January 2010 to December 2015 was conducted. Eleven patients were treated conservatively, and 26 patients underwent surgical restoration and internal fixation. Mouth opening and pain degree were used as indicators to analyze treatment results. RESULTS: The 37 cases of coracoid fractures accounted for 3.18% of the total mandibular fractures. The average age of patients was 38.05 years. Satisfactory results were obtained in both treatments. A considerable change in the degree of mouth opening before and after 6 months was found in the two groups. The pain degree before treatment and 1 day after operation, 1 day and 4 weeks after operation, and 4 weeks and 6 months after operation indicated that the two groups did not significantly differ. However, substantial changes between the two groups were found before treatment and 6 months after operation. CONCLUSIONS: Conservative treatment is recommended for patients with linear, temporalis muscle-located, and non-displaced coracoid fractures. Surgical treatment is recommended for patients with large fractures and those with accompanying zygomatic arch and mandible fractures.

Tryptase and TIM-1 double-positive mast cells in different stages of human chronic periodontitis.

BACKGROUND/PURPOSE: Mast cells (MCs) play a critical role in the pathogenesis of allergic reactions and inflammatory conditions through the release of inflammatory mediators. T cell immunoglobulin mucin domain (TIM-1) has been reported to express in MCs. The aim of the present study was to examine the expression and analyze the quantification of TIM-1 on tryptase-positive MCs in different stages of human chronic periodontitis using double-immunofluorescence staining. MATERIALS AND METHODS: Individuals who participated in this study were divided into three groups: healthy control gingivae (n = 27), chronic slight periodontitis (n = 34), and chronic severe periodontitis (n = 31). Their gingival specimens were taken and fixed in 10% buffered formalin, stained with hematoxylin and eosin (HE) for histopathology, and stained with double-immunofluorescence (DIF) for identification of tryptase-TIM-1 double-positive MCs in gingival tissues. RESULTS: Compared with healthy controls, the densities (cells/mm2) of tryptase-TIM-1 double-positive MCs were significantly increased in both the chronic slight periodontitis (P < 0.05) and severe periodontitis groups (P < 0.01). However, compared with the chronic slight periodontitis group, both the score of gingival tissue inflammation and the density of tryptase-TIM-1 double-positive MCs in gingival tissue were significantly increased in the severe periodontitis groups (P < 0.05). Conclusion: By incorporating HE with double-immunofluorescence staining in human chronic periodontitis, the significantly increased number of tryptase-TIM-1 double-positive MCs had the similar tendency as the severity of periodontitis inflammation. Based on our results, we suggest that tryptase-TIM-1 double-positive MCs may play an important role in human chronic periodontitis.

Expression of transforming growth factor-ß in mast cells in human chronic periapical diseases.

This study was undertaken to investigate the distribution of mast cells (MCs) and the expression of transforming growth factor-ß (TGF-ß) on tryptase positive MCs in different types of human periapical diseases. Periapical tissues of 78 participates were used in this study, including healthy control (n=28), periapical cyst (n=25), and periapical granuloma (n=25). The tissue samples were fixed in 10% formalin for at least 48 h, followed by staining with hematoxylin and eosin (HE) for histopathological examination. Then, they were stained with toluidine blue for MCs and MCs degranulation examination, or stained with double immunofluorescence for identification of tryptase-TGF-ß double positive MCs. The results showed that the density of tryptase-TGF-ß double positive MCs in periapical lesions was significantly higher than that of healthy control (P<0.01). The number of TGF-ß positive MCs in the periapical cyst was potently higher than that in the periapical granuloma (P<0.01). In addition, compared with toluidine blue staining, the number of MCs with double immunofluorescence staining was significantly increased (P<0.01). The TGF-ß positive MCs may play an important role in the pathogenesis of human chronic periapical diseases, particularly in the formation of fibrous tissues in periapical cyst. Double immunofluorescence staining is more sensitive than the traditional toluidine blue staining for identifying MCs.

[A study on repairing mandibular defect by means of tissue-engineering and human bone morphogenetic protein-2 gene transfection in osteoporotic rats].

OBJECTIVE: To investigate the feasibility of repairing bone defect with methods of tissue-engineering and human bone morphogenetic protein-2 (hBMP-2) gene transfection in osteoporotic rats. METHODS: Twenty-four 6-month-old female Sprague-Dawley rats underwent ovariectomy, while 8 rats received sham-operations. Three months later, bone mesenchymal stem cells (BMSC) harvested from osteoporotic rats were divided into two groups randomly. Experimental group were transfected by recombinant plasmid carrying hBMP-2 gene, and control group left untreated. All BMSC were seeded into coralhydroxyapatite scaffolds. Then the cell/scaffold constructs were implanted into the defect site created in the ramus of mandible of osteoporotic rats respectively. RESULTS: Positive results were confirmed by immunohistochemistry and in situ hybridization in experimental group. New bone formation was found at the margin of the defect treated with the BMSC modified by hBMP-2 gene transfer at 4 weeks after implantation and appeared mature 8 weeks after the treatment. However, the amount of newly formed bone was much less and there was some adipose tissue at defect margins 8 weeks after implantation in control group. CONCLUSIONS: The results of this experiment indicate that BMSC-mediated rhBMP-2 gene therapy in conjunction with bone tissue engineering may allow for successful treatment of large bone defects in osteoporosis rats.

[Cultivation and induced differentiation of bone marrow stromal cells of SD rats with type I osteoporosis in vitro].

OBJECTIVE: To study the biological features and osteoblast/adipocyte phenotypes of bone marrow stromal cells (BMSCs) of Sprague-Dawley (SD) rats with Type I osteoporosis by induced culture. METHODS: Six-month-old SD rats were used in this study. 16 female rats were randomly divided into two groups. Eight rats were ovariectomied as experimental group to establish the modle of Type I osteoporosis, while other rats received sham-operation. Three month later BMSCs of 16 rats were isolated by discontinueous gradient centrifugation and then plated in alpha-MEM medium as primary culture. Secondary harvested cells were cultured for 14 days in alpha-MEM medium supplemented with dexamethasone, ascorbic acid, vitamin D3, beta-glycerophosphate or dexamethasone, 3-isobutyl-1-methylxanthine, insuline, and indomethine. The cells were screened by inverted microscope each day and cell growth was studied with cell counting. The osteoblast and adipocyte phenotypes were verified by cytochemistry staining, counted the percentage of positive stained cells. RESULTS: The weight and bone mineral density of rats were statistically different between experimental group and control group. Gomori and Von Kossa's staining demonstrated positive osteoblast phenotypes of alkaline phosphatase and mineralized nods by osteogenic inducer, while Oil Red O staining identified BMSCs treated with adipogenic medium resulted in adipocyte formation and there was no significant difference in the percentage of positive stained cells between two groups. CONCLUSION: The model of Type I osteoporosis has been established successfully. BMSCs from SD rats with osteoporosis maintain their differentiation potential.

[In situ expression of transforming growth factor beta 1 in the process of induction chemotherapy for oral squamous cell carcinoma].

OBJECTIVE: To study the differential expression of transforming growth factor beta 1 (TGF beta 1) in oral carcinoma and stroma lymphocytes by induction chemotherapy and inquire into the mechanism of TGF beta 1 information transmission. METHODS: Forty cases of oral tumor were treated with MTX, CDDP and PYM via subcutaneous implantable drug pump, in situ hybridization method was adopted to detect the expression of TGF beta 1 mRNA. RESULTS: The positive expression of TGF beta 1 mRNA was enhanced in oral carcinoma (P < 0.05). After the induction chemotherapy via subcutaneous implantable drug pump, not only the expression level of TGF beta 1 in malignant cells of invading front zone was up-regulated (P < 0.05), but the expression level of stroma lymphocytes was higher than before. CONCLUSION: These data demonstrated that TGF beta 1 not only has transforming potential, but also enhances the malignant progression of oral carcinoma. It was clear that TGF beta 1 can act as a tumor suppressor and a significant stimulator of T-cell-mediated tumor cytotoxity as well.

[A study on myogenic differentiation of human adipose tissue-derived stromal cells].

OBJECTIVE: To isolate human adipose tissue-derived stromal cells and study the potential of osteogenic differentiation after inductive culture. METHODS: Liposuction human adipose tissues were minced and digested with collagenase type I. The obtained stromal cells were plated in BGJb medium as primary culture for ten days. The second passage cells were harvested and plated in DMEM/F12 medium supplemented with 10% FBS, 5% horse serum and 50 micromol/L hydrocortisone for myogenic induction culture. The cell-anchored slips were removed and fixed in 4% formaldehydam polymerisatum. Toluidine blue, Mallory's phosphotungstic hematoxylin staining and monoclonal antibody to human skeletal muscle myosin heavy chain immunocytochemical methods were used to assay the differentiation of cells. RESULTS: It was observed that the size and shape of induced cells were much different from those of non-induced cells. Toluidine blue, Mallory's phosphotungstic hematoxylin staining demonstrated there were many basophilic striations within cytoplasm and multinucleated myotubes were formed. Immunocytochemical stain indicated that characterastic skeletal myosin heavy chain was positive in myogenic induced cells. CONCLUSION: It seems that human adipose tissue represents an abundant reservoir of adult stem cells that have multi-germline potential to differentiate into myoblasts. Adipose tissue derived stromal cells will be another alternative source for cell-based tissue engineering in skeletal muscle reconstruction.