Objective To discuss morphology and biomechanics of the sacrum fractures so as to provide scientific basis for corresponding clinical treatment. Methods A total of 10 fresh pelvis specimens were collected for dynamic impact test and static destruction test, in the former one of which, the dynamic parameters were measured to make sure the dynamic characters of the fractures. Meanwhile, the fractures of the sacrum wing, the sacral foramina and the sacrum edge were made decalcification, slice of paraffin wax and staining (Masson, Mallory, HE) in order to make a cytological observation of the tissue. Results (1) The form of sacrum fracture or acetabulum fracture, crista iliaceis fracture was relevant to the impact energy. Low impact energy usually caused fractures of the ilium, acetabulum or sacroiliac crest. High impact energy resulted in following three kinds of fractures, just as the classification of Denis: sacral ala fractures belonged to typeⅠfractures, sacral hiatus fractures to type Ⅱ fractures and central vertebral canal fractures to type Ⅲ fractures. All three types of fractures might involve lateral or bilateral nerve roots. (2) There was a significant mechanic difference in regard of the mechanism of both dynamic destruction and static destruction of pelvis, ie, not only the limit pressure differed but also the former increased rapidly with the higher rate of the strain. The clash energy beyond 25 J would beget the cleft fractures of the sacrum via sacrum hiatus and even involve the nerve roots. The clash energy under 20 J usually resulted in fractures of the ilium and the sacrum. The clash energy between 20 J and 25 J more easily caused type Ⅰ fractures. While fracture of the ilium and the acetabulum would happen most in static destruction. (3) The cross section of the sacrum was cracked and the bone board of Haversian system is brittle, as led to separation of bone board and malposition of a few cross bone boards. Conclusions Under dynamic state, the sacrum fractures mostly belong to type Ⅰ and type Ⅱ (Denis classification of sacral fractures), usually involving the nerve roots. The sacrum fracture is relevant to the microstructure, the distribution of the bone trabecula, the osseous lacuna and the Haversian system of the sacrum. The fractures of the ilium and the acetabulum more frquently appear in static state, with slight wound of peripheral tissues.

Objective To discuss the diagnosis, treatment and prognosis of stage Ⅲ osteosarcoma. Methods A retrospective analysis of 23 patients with stage Ⅲ osteosarcoma of extremities from December 1989 to December 2003 was studied. There were 9 females and 14 males, aging from 16 to 31 years with a mean of 22.4 years. 15 patients presented with lung metastases, 7 with bone metastases (including 5 of jumping metastases and 2 of osteosarcomas) and 1 with lung and bone metastases simultaneously. Patients received chemotherapy followed by resection of primary and metastatic lesions and additional chemotherapy. Results After preoperative chemotherapy, lung metastases disappeared in 1 patient, whereas in 1 with lung and bone metastases simultaneously, the lesion remained surgically unresectable because of new metastases after removal of the primary lesion. In 2 patients with osteosarcoma, primary lesion could only be removed, lung metastasis appeared in 2 of 5 patients with jumping metastases respectively after the removal of primary lesion and jumping metastases. 16 patients with lung metastases received thoracotomy and resection of the lung metastatic lesions, and 6 of them received a second thoracotomy because of a second lung metastasis inclunding 3 cases with extra-pulmonary metastases without any additional treatment. The tumor necrosis rate was not found obviously different between primary lesions and metastatic lesions. Of the 23 patients who achieved a mean 74.6 months follow-up (range, 5-168 months), 9 remained continuously free of disease, 4 relapsed with new metastases, and 10 died of tumors. The outcome of the Cox model proportional hazard regression showed the relation of the number of the metastases and the prognosis were significant(P

AIM: To investigate influence of biomimetic nanoapatite coatings of titanium surface on behavior of osteoblasts-like and provide evidence for surface modification and biological effects of titanium implant.METHODS: Biomimetic nanoapatite coatings were developed by functionally modified methods with a combination of topographic,chemical and biomimetic treatments on the surface of titanium(Ti) substrate.The biological behavior and bioactivity of functionally modified SLA implants with chemical and biomimetic treatments(SCB-treated Ti) were investigated to compare with untreated Ti and SLA Ti plates as controls.The cell attachment,proliferation,alkaline phosphotase(ALP) activity,cell morphology and differentiation were evaluated by using MTT,RT-PCR,scanning electron microscopy(SEM) and confocal laser-scanning microscope(CLSM) analysis system.RESULTS: The cell adhesion and proliferation were enhanced on functionalized titanium surface with nano-scale apatite compared to the controls.SEM micrographs also revealed that the osteoblast-like cells spreadly grew along the surface.Cell morphology and differentiation were further observed distinctly by CLSM graphs.Moreover,mRNA expression of alkaline phosphotase on the SCBtreated Ti increased obviously on the twelfth day compared with the controls.CONCLUSION: The in vitro results demonstrate the remarkable improvement on cell adhesion and proliferation of the biomimetic nanoapatite on SCB-treated Ti,which could improve early bone-implant interface bonding ability and be used for orthopaedic/dental implants.

AIM:Many studies have documented an anabolic effect of hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, statins, on undisturbed bone. Reports of their effects on fractured skeleton were limited. A study was therefore conducted to check the effects of statins on fracture healing. METHODS: Simvastatin (10 mg?kg-1?d-1) was injected subcutaneously to tissue overlying the site of fractured tibiae of ovariectomized rats for a treatment period of 5 d. Vehicle reagent was used as control. Healing quality was evaluated at 1, 2 and 4 weeks after fracture. RESULTS: Compared with vehicle group, callus cross section area in simvastatin treated rats were significantly enlarged by 21.3% (P

Objective To investigate the aesthetic relations and internal regularities in normal craniofacial stereoscopic architecture. Methods By means of computer aided three dimensional measurement and analysis, a study on morphological features and inter relations of the cranio orbitozygomatic maxilla structures of twenty youths with pretty facial appearance was carried out. Results There were remarkable differences between each craniofacial structure in different sexes, but the ratio indices that represented the inter-relations of different craniofacial structures were closely similar in both sexes. In the group of youths the asymmetry ratios between bilateral craniofacial structures were below 5 % , presenting the perfect symmetry feature. The asymmetry ratios and their standard deviations of the zygomas and angulus mandibulae were relatively large . The results suggested that these two characteristic parts which influence the whole appearance were easily changeable with different individuals. There were close co relations between coronal axis width and sagittal axis protrusion in main structures of craniofacial region. These relationships could sum up in linear regression equations. Conclusion There are internal aesthetic regularities of coordinative ratios and harmonious symmetry in normal three dimensional craniofacial architecture, which determines the pretty appearance of youths. These internal regularities and aesthetic principles should be considered in designing and performing craniofacial aesthetic plastic operation so as to get excellent surgical results.

Objective To investigate the effect of caffeine and cisplatin induced apoptosis of osteosarcoma cell line(OS-732), and to explore the potential mechanism of caffeine enhancing cytotoxic effect of cisplatin in osteosarcoma cell line. Methods The OS-732 cell line was cultured for 72 hours; treated with caffeine, cisplatin and caffeine combined with cisplatin for 72 hours respectively, the apoptosis rates of OS-732 cell line were analysed by flow cytometry. Mitochondrial transmembranous potentials were measured by cellular rhodamine 123 stain on flow cytometry. Apoptosis was assessed by electron microscope at 80 kV. Results The OS-732 cell line was cultured for 72 hours; treated with caffeine (5.0 mmol/L ), cisplatin (10.0 ?g/ml ) and caffeine (5.0 mmol/L ) combined with cisplatin (10.0 ?g/ml) for 72 hours respectively. The apoptosis rates were 2.50%, 10.62%, 31.62% and 57.44% respectively. The percentage of decline of mitochondrial transmembranous potentials were 8.12%, 26.45%, 17.82% and 38.26% respectively. Electron microscope revealed the characteristic apoptosis alterations,such as shrinking cellular chromatin condensation, crescent nucleus, cytoplasmic vacuoles and so on. Conclusion Caffeine and cisplatin can induce apoptosis of osteosarcoma cell line(OS-732), while the cell line treated with caffeine and cisplatin simultaneously, the apoptosis rate was increased obviously. The induction of apoptosis of osteosarcoma cell line by caffeine may be one of potential mechanism enhancing cytotoxic effect of cisplatin in osteosarcoma cell line.

Objective To investigate the effect of three-dimensional gelatin-chondroitin sulfatehyaluronic acid (Gel-C6S-HA) composite scaffold seeded with genetically modified hair follicle stem cells (HFSCs) on tissue engineering skin angiogenesis.Methods Three-dimensional scaffolds composed of Gel-C6S-HA were fabricated by freeze-lyophilizing.VEGF165 modified HFSCs were seeded on those scaffolds and cellular morphology and adhesion were observed using scanning electron microscope.Eighteen rats were subjected to the full-thickness skin defects with dimensions of 1.2 cm × 1.2 cm on the bilateral sides of the back and covered with VEGF165 transduced HFSCs/Gel-C6S-HA scaffold (Group A),empty-vector transduced HFSCs/Gel-C6S-HA scaffold (Group B),Gel-C6S-HA scaffold (Group C),and vaseline gauze (Group D) respectively according to the random number table.At days 7,14,and 21 after surgery,wound healing was observed,HE staining and immunohistochemistry of CD31 and alpha smooth muscle actin (α-SMA) were performed,and microvessel density (MVD) was used to measure new blood vessel growth.Results Electron microscopy exhibited three-dimensional spongy structure of the scaffold with round or polygon apertures connecting mutually and the scaffold pore size of (133.2 ± 43.4) μm.Cells seeded on the scaffolds spread thoroughly out and anchored firmly after being cultured for 7 days.There were no obvious inflammation reactions on the wounds for all groups at day 7 after operation.Wound healing and scaffold degradation were faster in Group A than in other groups at days 14 and 21 after operation.Histological and immunological detections showed microvasculariztion of the scaffold in Groups A and B with fluffy three-dimensional structure and evenly distributed cells,but scaffolds remained sharp at the edge and there were small cells aggregating at subcutaneous tissue junction area in Group C.At 14 and 21 days after operation,new blood vessels were large and rich in Group A; scaffolds in Groups A and group B were filled with cells,partial of which gathered in the epidermal layer and the scaffold materials were assimilated differentially,whereas a few subcutaneous tissue cells migrated to scaffolds in Group C.MVD was significantly higher in Group A than in Groups B and C at each time point (P ＜ 0.05).Conclusion VEGF165 modified HFSCs compounded with Gel-C6S-HA composite scaffold can facilitate the growth of blood vessels and promote the angiogenesis in wound healing and hence is a promising skin substitute in clinical applications.

AIM: To investigate the effects of proteasome inhibitor Z-LLL-CHO(MG132) on human osteosarcoma cell line MG-63 and its possibly mechanism.METHODS: After treated with different concentration of MG132,the morphological change,ultrastructral morphology,cell viability,cell apoptosis,gene transcription and protein expression in MG-63 cells were accessed by fluorescence microscope,electron microscope,MTT assay,agrose gel electrophoresis,FCM,RT-PCR and Western blotting.RESULTS: Proteasome inhibitor MG132 was an effective inducer of apoptosis in human osteosarcoma MG-63 cells.Not only apoptotic changes,but also cell arrest at G2-M-phase,the accumulation of p27kip1,the accumulation of activated caspase-8 and increased ratio of Bax∶Bcl-2 were observed.However,to normal human diploid fibroblast cells,MG132 did not show apoptosis-inducing effect.CONCLUSION: Apoptosis induced by MG132 may be caspase-8,p27kip1and bcl-2-related.

AIM: To down-regulate expression of c-myc through antisense therapy and to investigate its effect on the sensitivity of osteosarcoma MG-63 cells to cisplatin-induced apoptosis. METHODS: The recombinant adenovirus (Ad-Asc-myc) encoding antisense c-myc fragment was constructed and transfected into osteosarcoma MG-63 cells in vitro in order to down-regulate the expression of c-myc, and the change in the sensitivity to cisplatin-induced apoptosis was observed. MTT, Western blot, RT-PCR, flow cytometry (FCM) and electron microscope were used to evaluate tumor cell proliferation in vitro, genes expression related to apoptosis regulation and effects on the sensitivity of osteosarcoma MG-63 cells to cisplatin-induced apoptosis. RESULTS: Ad-Asc-myc down-regulated the expression of c-myc protein after transfected MG-63 cells for 48 h, combined with the treatment of 2.0 mg/L cisplatin for 2 h inhibited tumor cell proliferation in vitro by 38.0%. RT-PCR revealed that Ad-Asc-myc down-regulated the expression of Bcl-2 and up-regulated the expression of Bax. No appreciable change was observed in the expression of E_2F-1. FCM showed that Ad-Asc-myc induced apoptosis in intransfected cells, and rendered it more sensitive to cisplatin. CONCLUSION: Antisense c-myc is able per se to induce apoptosis and sensitize osteosarcoma cells to cisplatin-induced apoptosis.

AIM: To study whether caspase-3,8 is activated during azurin-induced apoptosis in U2OS cells. METHODS: AnnexinV /PI method was used to detect apoptosis. The changes of procaspase-3 were analyzed by Western blot, the changes of caspase-3 mRNA were detected by semi-quantitative RT-PCR, and caspase-3 relative activity was determined by colorimetric assay. RESULTS: After U2OS cells were treated with 0, 25, 50, 100, 200, 500 mg/L azurin for 24 h, respectively, the level of procaspase-3 protein decreased and the level of caspase-3 mRNA increased as azurin concentration increased. When the cells were treated with 100 mg/L azurin for 6, 12, 24, 48 h , respectively, the caspase-3 activity began to rise from 6 h,reached the peak at 24 h,and was still higher than the control group at 48 h ( P