砄bjective: To study the rule of the degradation of HA artificial bone(HAB). Methods: The samples of HAB were immersed in PBS or distilled water (DW),the changes of the shape, weight, compressive strength of the samples and pH value of the immersion solutions were measred at the intervals of 2 or 4 weeks until 28 weeks. Results: At 4 weeks, HAB began to be degraded, 8 weeks later, the speed of the degradation slowed down. From 4 to 12 weeks, the compressive strength decreased rapidly. The pH value of the immersion solutions decreased from 2 to 12 weeks,but increased from 12 to 28 weeks when it was close to the neutral value. Conclusion: HA artificial bone can be degraded in PBS solution, and the degradation can cause noticeable changes of the compressive strength of the material and pH value of the immersion solution.

砄bjective: To establish PTEN gene transfected mucoepidermoid carcinoma cell line. Methods: Wild type PTEN gene was transducted into a highly metastatic mucoepidermoid carcinoma cell line by using lipofectamine. The positively transfected cell clones were selected with puromycin. The expression of PTEN protein in the cells was determined by western blot and immunohistochemical methods. Results: An anti puromycin cell clone was obtained and expanded in culture. Western blot and immunohistochemical staining revealed that the PTEN protien was expressed in the transfected cells. The cells were named M 3SP 2 PTEN. Conclusion: M 3SP 2 PTEN is a cell line expressing exogenous PTEN protein.

?Objective:To study the effects of Docetaxel on the proliferation and metastatic potential of mucoepidermoid carcinoma M 3SP 4 cells in vitro and in vivo . Methods:Inhibitory effects of Docetaxel on the proliferation and metastatic potential of mucoepidermoid carcinoma M 3SP 4 cells were investigated with cell counting,cloning assay flow cytometry, tail vein injection and submandibular gland injection of the cells into nude mice. Results:Docetaxel inhibited M 3SP 4 cells growth in a dose and time dependent way. The IC 30 and IC 50 (with 72 h exposure) of Docetaxel were 0.34 nmol/L and 0.63 nmol/L, respectively; the doubling time(h) of the cells treated with the drug at IC 30 for 7 days and of the control were 32.7 h, 43 h, respectively; the clonogenesity(%) of the control and of the cells treated with Docetaxel ( 0.05 nmol/Lor 0.1 nmol/L)were (29.2?1.4)% and (20.2?0.8)% and (2.8?0.4)%, respectively; the number of metastatic foci on lung surface in the nude mice treated with the drug at 30 mg/kg?week and in the controls were 0 and 11?3.4; the weight(g) of submandibular gland in the two groups were 0.31?0.05 and 1.20?0.23 respectively. Conclusion:Docetaxel may inhibit the proliferation and metastatic potential of mucoepidermoid carcinoma M 3SP 4 cells.

Objective: To establish a metastatic cell line from distant organ metastasis using Mc3 cell line in nude mice. Methods: Tail vein injection of Mc3 cells and cell culture technic were employed to induce metastasis in distant organ . Cell counting and flow cytometry were used to study the cell growth. Karyotype analysis and histopathological observation were used to study the morphological features with light and electron microscopy. Results: Paralized nude mouse was observed in 1 out of 50 experimental nude mice. The cells derived from the spinal cord were cultured and transferred for more than 50 passages. The cells were proved to be of mucoepidermoid carcinoma from human being by the morphology, histopathology and karyotype of the cells. The population doubling time and S-phase cell of the cells were 43 h and 22.7% respectively. The cell line was named Ms. Conclusion: Ms is a metastatic cell line of spinal cord metastasis in nude mouse derived from human mucoepidermoid cacinoma cells.

Objeact:To evaluate the effects of the exogenous PTEN gene on morphology of the highly metastatic mucoepidermoid carcinoma cell line M3SP2. Methods: Morphological observation of vehicle transfected M3SP2-pBp cells and PTEN transfected M3SP2-PTEN cells was performed with inverted microscope, HE staining and optical microscope, scanning electronic microscope and transmisson electronic microscope. Results: Compared with the control cells of M3SP2-pBp, the exogenous PTEN expressing cells M3SP2-PTEN showed morphological changes, such as vacuole denaturalization, shrinkage, less microvillus, chondriosome swelling, lysosome amalgamation, and chromatin agglutination. Conclusion: The exogenous PTEN gene may induce denaturalization, necrosis, and apoptosis of the highly metastatic mucoepidermoid carcinoma cells.

Objective To collect information of patient doses of interventional radiology in Beijing Xuanwu Hospital,and investigate correlation between the peak skin dose(PSD) and dose-area product(DAP).Methods Radiation doses from 135 patients have been studied including 84 coronary angiographies(CAG) and 51 percutaneous transluminal coronary angioplasties(PCI).Dose-area product(DAP) values,cumulative dose(CD) at interventional reference points,fluoroscopy times,total number of cine frames were collected for each patient.Skin dose measurements were made with thermoluminescent dosimeters(TLD) placed as a 10 ? 9 arrays of TLDs on the body.The grid of TLDs arrays was 5 ? 4 cm.Results Mean values for dose-area product were 2690.84 ?Gym2 for CAG and 7946.91 ?Gym2 for PCI.Mean values for CD were 431.6 mGy cm2 for CAG and 1395.3 mGy for PCI.Mean fluoroscopy times were 2.9 min for CAG and 10.9 min for PCI and mean number of frames were 544 and 945 for CAG and PCI,respectively.PSD values ranged from 26.18 to 120.37 mGy for CAG and 38.91 to 184.79 mGy for PCI.The relationship between DAP and PSD was r = 0.52 for CAG and r = 0.54 for PCI.The correlation of PSD with CD was r = 0.45 for CAG and r = 0.53 for PCI.Conclusion Comparison shows that patients DAP,CD and fluoroscopy time values were comparable with other publications.Skin dose values of investigated patients are below the threshold dose for radiation skin injury(2 Gy).There is no good relationship between DAP and PSD.So calculation of individual maximum skin dose based on DAP data is not reliable and needs to find a new reference value for skin dose.(J Intervent Radiol,2007,16:222-225)

Objective: The purpose of this study is to investigatc the effects of the HAB/DBP composite in the restoration of restoring bone defects. Methods: The HAB/DBP composiite, HAB or DMB samples were grafted into the defects of rabbit's radii respectively and the samples were examined 2 weeks, 4 weeks, 8 weeks and 12 weeks after operation with general, radiological and histological observations respectively.Results: In the group of HAB/DBP composssite implanted area , mesenchymal cells and new bone stromas were observed assembling 2 weeks after the operation. New bone formation and bone trabeculation were found 4 weeks after transplantation. A lot of bone trabeculation and composite degrad ation were observed 8 weeks after operation. The defects were completely restored 12 weeks after the surgery.Conclusion: The HAB/DBP composite has the properties of osteoconduction and osteoinduction, and its osteogenic ability is similar to that of DMB.

BACKGROUND: Cytogenetic evidence suggests that chromosomal alteration are not randomly occurring events and some malignancies are characterized by specific chromosome abnormalities, which provides cytogenetic basis for the expression of oncogenes.OBJECTIVE: To investigate the characteristics of chromosomal karyotype and marker chromosome of breast cancer cell lines Bcap-37and MCF-7 by means of G-banding chromosomal analysis.DESIGN: A controlled experiment with breast cancer cells as observation subjects.SETTING: Department of Medical Genetics, Peking University Health Science Center.MATERIALS: This study was carried out in the Department of Medical Genetics of Peking University Health Science Center from April 1991 to May 1992 using breast cancer cell lines MCF-7 and Bcap-37.METHODS: The chromosomes of human breast cancer cell lines Bcap-37and MCF-7 were obtained by growth synchronization induced by hypothermia and colchicines treatment. The cells at prometaphase or metaphase underwent G-banding chromosomal analysis. For each cell line, 50 to 60 mitotic figures were counted and 15 or 16 G-binding karyotypes were analyzed, including the mitotic figure at the level of about 320- and 500-band .MAIN OUTCOME MEASURES:Abnormality in chromosome number and structural aberration of the two breast cancer cell lines.RESULTS:The modal chromosomal number of Bcap-37 cell line was 63, of which 17 marker chromosomes had identifiable structure, as compared with 13 out of 56 chromosomes in modal number of MCF-7 cell line.CONCLUSION: Both of the two breast cancer cell lines have complex cytogenetic abnormality in the modal number and structure of the chromosomes, which might result in the rearrangement of DNA sequence of the cancer-related genes or DNA depletion, so as to play important roles in the pathogenesis and development of breast cancer.

Objective To investigate the treatment of Pipkin fractures and curative effect. Methods From January 2003 to November 2009, we treated 19 cases of posterior dislocation of the hip with fracture of the femoral head,with type Ⅰ 8 cases, type Ⅱ6 cases, type Ⅲ 1 case, type Ⅳ4 cases. Seventeen patients were treated according to the illness with internal fixation treatment. Results Among type Ⅰ 8 cases, 2 cases were good with conservative treatment, 3 were excellent and 3 were good with surgical treatment;Among type Ⅱ6 cases, 3 were excellent, 2 were good, 1 was fair; 1 patient of type Ⅲ was fair; In 4 cases of type Ⅳ, 1 case was excellent, 2 cases were good, 1 case was fair. Conclusions Surgical treatment as soon as quickly is preferred for posterior dislocation of the hip with fracture of the femoral head( Pipkin fractures) , but the surgical time and methods should be chosen according to patients' detailed illness. It is important reserving the hip bone for preventing traumatic arthritis, and surgical skills to protect blood supply should not be ignored.

Objective:To establish a multidrug resistant model of human mucoepidermoid carcinoma using nude mice. Methods:Multidrug resistant MEC/5-FU cells were inoculated intradermally into nude mice. Solid tumors were locally measurable after 10 days and 5-FU was repeated intraperitoneal injected into tumor-bearing mice. The tumor cells in nude mice (MEC/5-FU/NU) were isolated, cultured and examined. Results:The xenografts were similar to the original mucoepidermoid carcinoma from which the cell line was derived. The resistance index (RI) of the MEC/5-FU/NU cells to 5-FU was 27.82. Compared to the MEC, the expressions of ABCB1, ABCB11 and GSTA1 genes and MDR-1 protein increased in the MEC/5-FU/NU cells(P<0.05). Conclusion:The xenograft model is a good model of human multidrug resistant mucoepidermoid carcinoma, and may be useful in studying drug resistance mechanism in vivo.