Objective: To investigate the growth inhibition and apoptosis induction effect of vitamin E succinate (VES) on human colon cancer cells and to analyze the modulation of apoptosis-mediator Fas expression in this process. Methods: Human colon cancer cell line LS174T was treated with VES for 12 h, 24 h and 48 h at the concentrations of 5 mg/L, 10 mg/L and 20mg/L. 1-(4,5-dimethylthiazo-2-yl)-3,5-diphenylformazan (MTT) assay was employed to detect the inhibitory effect of VES on the growth of colon cancer cells. Flow cytometry was then used to analyze the cell cycle of the colon cancer cells after being treated with VES and the apoptotic rate was calculated at the same time. To find out whether the Fas protein expression was modulated in this process, Western blotting assay and flow cytometry were used to detect the Fas protein level in whole cell lystates and on cell surface. Results: VES exhibited a significant inhibitory effect on the growth of human colon cancer cells in a doseand time-dependent manner. After being treated with VES at 5 mg/L, 10 mg/L and 20 mg/L for 48 h, the apoptotic rate of LS174T cells rose from 0.90% to 15.9%, 46.7% and 64.5%, respectively. Fas neutralizing antibody can significantly block VES-induced apoptosis. After the administration of VES, total Fas protein in whole-cell extracts increased in a dose-dependent manner. The flow cytometry showed that the mean fluorescence intensity rose from 5.43 to 9.88, 13.21 and 18.0 after being treated with VES. Conclusion: VES can induce significant growth inhibition and apoptosis in human colon cancer cells. The modulation of Fas expression is one of the mechanisms involved in this process and may be related to the upregulation of Fas molecule on the cancer cell surface.

Tuberculosis (TB) is a global burden disease and is being resurrected as a major worldwide public health problem after two decades of neglect.In 1993,the World Health Organization (WHO) declared that TB had been a global emergency because of the scale of the epidemic and the urgent need to improve global tuberculosis control.China is one of the countries with the largest population,and also the top of the 22 TB high-burden countries in the world.In the United States,the longstanding downward trend in TB incidence was interrupted in the mid-to-late 1980s,where the national TB incidence peaked in 1992.Sub-Saharan Africa is one of the three regions to dominate the worldwide distribution of notified TB cases.Of the 15 countries with the highest estimated tuberculosis incidence rates in the world,13 are in sub-Saharan Africa,where HIV is the most important single predictor of tuberculosis incidence.The largest share of the global burden of HIV-related tuberculosis falls on this region.The reasons for the persisting global tuberculosis burden include increased poverty in some regions,immigration from countries with high tuberculosis prevalence,the impact of HIV,and most importantly,the failure to maintain the necessary public health infrastructure under the mistaken belief that tuberculosis was a problem of the past.Relying on currently available methods of diagnosis and treatment,the DOT strategy promoted by the WHO for global tuberculosis control is effective,affordable,and adaptable in different settings.

Objective: To study the application of CT and MRI fusion technique in the diagnosis and treatment of intraocular and orbital tumors. Methods: 2D-images of 13 patients with intraocular and orbital tumors were fused by special-point registration and Iterative Local Closest Point(ILCP) method; 3D-fusion images were reconstructed by Ray Tracing method. Results: A 3D-CT-MRI fusion images of intraocular and orbital tumors were reconstructed and displayed. The CT and MRI data of intraocular and orbital tumors were displayed on the same image as a comprehensive whole,which provided a stereogram of 3D-structure of the normal and abnormal orbital tissues. Anatomical structure of the orbit was clearly visualized by 3D-CT-MRI image. Conclusion: The multi-modality fusion technique can provide more accurate and comprehensive information for clinical diagnosis of intraocular and orbital tumors, which is helpful for doctors' planning of surgical operations,clinical education and doctor-patient communication.

Objective: To evaluate the efficacy of the third-generation instrumentation including TSRH, CD and ISOLA in the treatment of adult scoliosis. Methods:Thirty-five adult patients with idiopathic or degenerative scoliosis who received treatment with third-generation instrumentation (TSRH,CD and ISOLA) between July 1999 to January 2003 were retrospectively reviewed. The mean preoperative cobb angle of major curves of the frontal plane was 58.1°(42°-95°). The patients received a combined anteroposterior approach or a single posterior procedure. The mean follow-up time was 20 months(10-48 months). Preoperative and postoperative Cobb angles of the frontal plane and sagittal plane and the distance between C7 and CVLS were measured. The subjective assessment was judged by questionnaire. Results: Postoperative clinical appearance of all patients improved significantly. Mean correction of major curves of the coronal plane was 53.2%. Mean loss of correction of the coronal plane in the last follow-up was 4.3°. The distance between the midline of C7 and CVSL was corrected from 2.6 cm to 0.24 cm. The results of follow-up showed that 89.3% patients were satisfied with the outcome. Pneumatothorax and haematothorax occurred in 2 patients. Three patients still complained of low back pain one year after operation because of adjacent degeneration in 2 patients and pseudoarthrosis in the remaining 1 patient. Conclusion: Imageologic findings and subjective assessment of the patients showed that the third-generation instrumentation can achieve good correction and trunk balance in the treatment of adult scoliosis with fewer complications.

Objective:To optimize the injection protocol of contrast medium for contrast-enhanced MRA (CEMRA) of pulmonary artery and to evaluate the diagnostic value of CEMRA and pulmonary perfusion imaging (PPI) in an experimental model of acute pulmonary embolism. Methods:CEMRA and PPI were performed in 6 normal pigs with different doses of gadolinium contrast agent (5ml, 10ml, 15ml, 20ml and 25ml) at an injection rate of 3ml/s, and 3 pulmonary embolism models were injected with 20 ml contrast agent at 3 ml/s. DSA was also performed for comparison. Results:The signal intensities and the signal to noise ratios of the pulmonary arteries kept increasing with the dose increase of the contrast agent, but the best angio-pulmonary contrast dose was 10-15ml (0.25-0.375mmol/kg), while the optimal dose for PPI was 15-20ml (0.375-0.5mmol/kg). Although CEMRA demonstrated less obstructed pulmonary arteries than DSA (5/10 vs 8/10)did, it detected all obstructions when combined with PPI. The pulmonary infarction zones showed wedge-shaped perfusion defects on the PPI images, with the signal intensities lower than those of the normal areas (137.86±45.32 vs 330.14±46.52, P<0.001). Conclusion:It is suggested that the optimal dose of the contrast agent is 0.25mmol/kg to 0.375mmol/kg for CEMRA, and 0.375mmol/kg to 0.5mmol/kg for lung perfusion. CEMRA combined with PPI may be better than DSA in demonstrating pulmonary embolism.

Objective: To investigate the function and mechanism of phospholipase Cγ1 (PLCγ1) in cell-matrix adhesion in colorectal cancer. Methods: Highly metastatic colorectal cancer cell line LoVo and lowly metastatic colorectal cancer cell line SW480 were subjected to cell-matrix adhesion assay. U73122 (a specific inhibitor of PLC) and pyrrolidine dithiocarbamate (PDTC) (an inhibitor of NF-κB) were used to study the effect of PLCγ1 and NF-κB on cell-matrix adhesion. Furthermore, Western blot and gel electrophoresis mobility shift assay (EMSA) were performed to detect the mechanism of PLCγ1 in colorectal cancer cell adhesion to matrix. Results: Inhibition of PLCγ1 or NF-κB resulted in reduction of cell-matrix adhesion in a dose-dependent manner in LoVo cells(P<0.05), but had no marked effect on SW480 cells. Western blot analysis showed that epidermal growth factor (EGF) stimulated the phosphorylation of PLCγ1 in LoVo. The results of EMSA indicated that inhibition of PLCγ1 signaling pathway also down-regulated the activity of NF-κB while EGF reversed the function. Conclusion:These data suggest that PLCγ1 plays a pivotal role in the EGF-induced cell-matrix adhesion of highly metastatic colorectal cancer cells and that NF-κB is also functional in this signaling pathway.

Objective: To construct the extracellular region of PCP-2(PCP-2EC) and the immunoglobin IgG Fc fusi on protein expression vector,and then express and purify the soluble PCP-2EC/Fc fusion protein for the study of its function in neuronal adhesion. Methods: PCP-2 extracellular region was amplified and cloned into an expression vector pIGplus containing human IgG Fc; PCP-2EC/Fc fusion protein was expressed by COS-7 and 293 cells transfected by the constructed plasmid and purified by protein A. The purified fusion protein was used as substrate to study its function in neuronal adhesion. Results: PCP2 extracellular region was cloned into IgG Fc expression vector successfully; PCP 2EC/Fc fusion protein was expressed and purified in mammal cells; and the purified fusion protein promoted neuronal adhesion. Conclusion:PCP 2EC/Fc fusion protein expression system is successfully constructed and the purified fusion protein can promote neuronal adhesion. These results lay a foundation for the research on the PCP-2 function in neuronal adhesion and the further functional study in the nervous system and other fields.

Objective: To observe morphological changes of epithelial-mesenchymal transition in the early stage of mice renal interstitial fibrosis. Methods: Renal interstitial fibrosis was induced by unilateral ureteral obstruction(UUO) in mice. Histological and immunohistochemical methods were used to analyze pathological changes and α-SMA expression in renal tissue.Argentum hexamethylenamine staining and transmission electron microscopy were used to observe changes of the renal tubule basement membrane. Gelatin zymographic analysis was used to observe the expression of MMP2 and MMP9 in renal tissue.Results:The mice suffered from renal interstitial fibrosis were identified by histological analysis and α-SMA positive cells in renal tissue. Argentum hexamethylenamine staining and transmission electron-microscopy showed that the renal tubule basement membrane disrupted locally and renal tubule epithelial cells invaded into the renal interstitium in the early stage of renal interstitial fibrosis. Gelatin zymographic analysis showed that the expression of MMP2 and MMP9 was increased transitorily in the early stage of renal interstitial fibrosis. Conclusion: Renal tubule basement membrane disruption, renal tubule epithelial cells invasion into the renal interstitium, and the expression of MMP2 and MMP9 are involved in the development of renal interstitial fibrosis.

Objective:To determine whether heme oxygenase-2(HO-2) gene deletion can attenuate oxidative injury induced by free Fe2+. Methods:Stereotactic injection of 10 μl sterile FeCl2 (10 mmol/L) was made into the right striata of HO-2 knockout mice and wild-type mice. Brain edema severity was measured at 24 h. Cell viability, protein oxidation, and lipid oxidation of the basal ganglia were determined at 72 h. Western blot analysis was applied for heme oxygenase-1 (HO-1) measurement.Results: Brain water content significantly decreased in HO-2 knockout mice at 24 h compared with wild-type mice. Protein oxidation and lipid oxidation significantly decreased in HO-2 knockout mice at 72 h compared with wild-type mice, while the striatal cell viability increased significantly. HO-1 expression at baseline and 72 h was also similar to that in wild-type mice. Conclusion:These results show that HO-2 gene deletion can protect basal ganalia cells from free Fe2+ -mediated oxidative stress injury,suggesting that selective inhibition of HO-2 may have a protective effect on brain oxidative injury.

To study the effect of soybean isoflavone on liver oxidative stress resulting from 60Co-gamma rays. Methods: Totally 80 normal female Kunming mice were evenly randomized into 5 groups according to body weight: 3 intervention groups, single irradiation group and normal control group. The normal group and single irradiation groups were given 0.5% CMC-Na, and the 3 intervention groups were given different doses of soybean isoflavone (50 mg/kg, 100 mg/kg, 400 mg/kg) respectively for 14 d. The whole body of single irradiation group and intervention groups were subjected to 4.56 Gy 60Co-γ radiation once on the 7th day, and then the mice were killed on the 2nd day and the 7th day after radiation. Results: The CAT activity of liver tissue of 100,400 mg/kg intervention groups and 3 SI groups were significantly increased on the 2nd day and 7th day after irradiation(P<0.05), respectively; the GSH-Px activity of 100 mg/kg SI group was significantly increased(P<0.05) on the 7th day after irradiation; the T-SOD activity of 50 mg/kg SI group was significantly decreased (P<0.05) on the 2nd day after irradiation,while no difference was observed among remaining groups. The MDA content of 100 mg/kg group was significantly decreased on the 7th day after radiation compared with control group, and MDA content of each group subjected to irradiation were increased on the 2nd day after irradiation,but 3 SI groups nearly decreased to normal level on the 7th day after irradiation. Conclusion: The soybean isoflavone can enhance the antioxidant capability of mice, but it does not show a dose-effect relationship.