Objective To investigate the change of S-100B in serum in rats at varions times after exposure to different whole-brain irradiation doses and to explore the characteristics of the S-100B change in early radiation-induced brain injuries. Methods A model of brain radlation-induced injuries was estabhshed in the rat after whole-brain irradiation with a single dose of 2, 10, or 30 Gy of 4 MeV electron. The concentration of S-100B in serum was detected by means of enzyme-linked immunoserbent assay (ELISA) at different time points (1,6,12,24,3 days, 1 week, 1 month) after exposure. Results In terms of measuring time points, the serum concentration in all groups reached the fwst peak 6 hours after irradiation, declined after 12 hours, rose again after 24 hours, and started to decline again until the last time point (1 month), with the exception of the 2 Gy group, which reached the second peak at 3 days after irradiation. Conclusions The S-100B serum concentration was changed in the rats after whale-brain irradiation and these changes are positively related to the irradiation amount. It seems that the higher the dose, the higher the serum concentration and the differences between the dose groups are significant (via multiple regression models). The S-100B may be a valuable serum marker for the brain irradiation injury.

OBJECTIVE:To summarize the materials, design, fit-shape and fixation techniques and clinical application of temporomandibular joint (TMJ) prosthesis.DATA SOURCES: An online search was undertaken to identify English articles about TMJ prosthesis published in Pubmed database from January 1998 to December 2006 using the key words of "temporomandibular joint, joint prosthesis".STUDY SELECTION: The collected literatures about TMJ prosthesis were sorted, and those with good pertinence were selected. For the literatures of the same field, those published recently or in authorized journals were selected.DATA EXTRACTION: Totally 69 literatures were collected, 28 were enrolled, and the other 41 were excluded, including 23 were irrelative with the aim of this study, and 18 were repetitive studies.DATA SYNTHESIS: Joint prosthesis is one of the fields that develop the fastest in orthopedic surgery in recent 30 years.TMJ replacement aims to enhance the function of TMJ, alleviate pain, and prevent serious complication. With the rapid developments of material science, tissue engineering, joint biomechanics and other related subjects, TMJ prosthesis has been significantly improved in the materials, design, fit-shape and fixation techniques. People have developed from simply imitating the outline form and mechanical motor of TMJ to pay more attention to its pathological function. It is very significant to trace the new progress in hip prosthesis and knee joint, and apply the good outcomes in the design and manufacture of TMJ prosthesis.CONCLUSION: Prosthetic material plays leading and promoting roles in the development of joint prosthesis, good design,fit-shape and fixation are the necessary conditions for prosthesis to act its role, and it is also necessary to investigate joint biomechanics. TMJ prosthesis should be further investigated, and it has good prospect.

Complete surgical resection is very important for the outcome of cancer treatment and prognosis.Radionuclide imaging and optical imaging are effective methods for intra-operative guidance of tumor exploration and resection because of their capability in accurate tumor localization and margin delineation.With the development of more specific molecular probes and more sensitive detectors,advanced imaging methods that combine the advantages of both optical and radionuclide imaging,such as Cerenkov luminescence imaging,will be expected to play a more important role as intra-operative navigating agents for surgical oncology in the near future.

BACKGROUND: Previous research has indicated that both insulin-like growth factor Ⅰ (IGF-Ⅰ) and basic fibroblast growth factor (bFGF) play an important role in cell proliferation and differentiation. However, the effect on biological characteristics of human dental papilla mesenchymal cells (hDPMCs) still remains unclear. OBJECTIVE: To research the effect of IGF-Ⅰ and bFGF on the proliferation and differentiation of hDPMCs.METHODS: hDPMCs were isolated and cultured in DMEM/F12 culture media containing 1% or 10% fetal bovine serum. The fourth-passaged hDPMCs were incubated in culture media containing 0, 0.1, 1, 10 and 100 μg/L bFGF and 0, 25, 50, 75 and 100 μg/L IGF-Ⅰ(0 μg/L as control group), respectively. At 96 hours after culture, proliferative activity was measured with MTT assay. The corresponding growth factor culture media were used in 10 μg/L bFGF group, 100 μg/L IGF-Ⅰgroup, bFGF + IGF-Ⅰ group, and control group, respectively. At days 1, 3, 5, and 7 after culture, the proliferative activity was detected using MTT assay, and alkaline phosphatase (ALP) activity was measured using modified enzyme kinetics method. RESULTS AND CONCLUSION: At the 0-100 μg/L mass concentration scope, both bFGF and IGF-Ⅰcould accelerate proliferation of hDPMCs, and the proliferation ability of bFGF was superior to that of IGF-Ⅰ; moreover, the combination of bFGF and IGF-Ⅰcaused a synergetic action to proliferation of hDPMCs. The maximal valid concentration of bFGF was 10 μg/L, and the maximal action concentration of IGF-Ⅰwas 100 μg/L. At 0-7 days, the effect of bFGF on the ALP activity of hDPMCs was not obvious, but the effect of IGF-Ⅰon ALP activity of hDPMCs became greater with the time passing; furthermore, the combination of bFGF and IGF-Ⅰcould generate a synergetic action on increasing the ALP activity.

MicroRNAs (miRNAs) are a novel class of small noncoding RNAs that regulate gene expression by targeting mRNAs for either cleavage or translational repression.Accumulated studies show that miRNAs aberrantly expressed in tumors are closely related with tumorogenesis and could be potential tumor biomarkers.It will be helpful in the diagnosis,prognosis and(or) predicting treatment response of tumor by imaging miRNAs expression.Several molecular imaging methods,including the optical imaging,radionuclide imaging and multimodality imaging,have been successfully used to visualize miRNAs,miRNAs,a new molecular imaging target,may explore a new field for tumor diagnosis and therapy.

Objective:To investigate the effects on the new bone formation by different distraction rate during mandibular distraction osteogenesis in goats.Methods: The right side mandibles of twelve goats were distracted after corticortomy,and all the animals were divided into 3 groups randomly, the first group were distracted with 0.8 mm/day, the second group were distracted with 1.6 mm/day, the third group were distracted with 2.0 mm/day, and the left side mandible of 4 goats from above groups were selected randomly as the control group.Then the new generation bone after distraction with different rate were studied by bone density examination and three point bending test.Results: The bone density value of the 0.8 mm/day group were higher than the other two experimental groups; the results of three point bending test showed that the biomechanical strength of the new generation bone in 0.8 mm/day group was higher than the other two experimental groups.Conclusion:0.8 mm/day may be the best distraction rate in mandibular distraction osteogenesis.

Objective:To study the effects of LeFort I osteotomy in the treatment of old maxillary fracture.Methods:30 patients with old maxillary fracture were treated with LeFort I osteotomy,the rehabilitation of occluding relation and masticatory function were observed after operation.Results:28 patients had well-pleasing occluding relation and masticatory function; 2 patients dissatisfied with their masticatory function, because of unbalance of nerve-muscle after their occlusal plane were rebuilt.Conclusion:LeFort I osteotomy can be a method in the treatment of old maxillary fracture.

Objective:To investigate the biological characteristics of dental epithelial cells derived from cervical-loop epithelium in rat lower incisor. Methods:The apical end of the lower incisor was dissected from two-day-old Sprague-Dawley rats by visual microscopy, and dental epithelial cells were obtained by culture of the apical end explants of the lower incisor. The biological characteristics of dental epithelial cells were determined by morphology and immunocytochemistry fluorescence. Results:Dental epithelial cells emigrated from the cervical loop of rat lower incisor, and epithelium-like morphologies with round-shape or square-shape was observed. Dental epithelial cells had a striking proliferation potential with a high level of BurdU labeling. As a marker of epithelium stem cells, P63 expression was observed in most early cultured cells. However, as cells were subcultured, dental epithelial cells,with the lower level of BurdU labeling,decreasing expression of P63 and increasing expression of alkaline phosphatase, were inclined to terminal differentiation.Conclusion:Stem cells or dental epithelial progenitor cells might reside in the cervical loop of the apical end of the rat lower incisor. The present study may provide an excellent cell source for study on the differentiation of dental epithelial cells and tooth regeneration.

砄bjective:To investigate the expression of integrin ? 1 during mandibular fracture healing.Methods:Rabbit mandibular fracture model was used,the fractured bone tissues were obtained and paraffin slices were made on the day 1,3,5,7,14,30,60 and 90 after surgery respectively.Non fractured mandible was used as the control.The expression of integrin ? 1 in bone tissue, especially in osteoblasts and osteoclasts, was studied with LsAB immunohistochemical method.Results:Integrin ? 1 was widely espressed in the bone tissure close to fracture and surrounding soft tissue.In osteoblasts increased expression of integrin ? 1 was observed on day 7,maximum on day 14～30 and normal on day 90.While in osteoclasts,it was increased and kept at maximum 14～90 days aftere fracture.Conclusion:During mandibular fracture healing,the expression of integrin ? 1 in bone,especially in osteoblasts and osteoclasts,was increased.Integrin ? 1 has a critical influence on bone fracture healing.

objective: To study the effects of induction chemotherapy via subcutaneous implantable drug pump on local immune status. Methods: 47 cases with node negative oral cancer were treated with MTX, CDDP, PYM via subcutaneous implantable drug pump(in 27 cases), or via vein for case control trial(in 20 cases). Local immune status of tumor tissue was detected by immunohistochemical technique before and after treatment. Results: The effectiveness of treatment with the drugs via subcutaneous implantable drug pump (DSIP) was observed in 21 out of 27 cases (77.8%) and that with the drugs via vein(DV) was in 13 out of 20(65.0%) respectively( P 0.05), while the number of positive cells of CD 4 and CD 4/CD 8 in the cases treated with DV was decreased( P