Objective To explore the effects of subchronic arsenic exposure through drinking water on glutamate-glutamine cycle in the brain of mice. Methods The female Kunming mice were exposed to arsenite ( iAsⅢ ) by drinking water at the levels of 25, 50 and 100 mg/L respectively for 6 consecutive weeks. The blood and brain were taken, the concentration of inorganic arsenic (iAs), monomethylarsenic acid (MMA), dimethylarsenic acid (DMA) and the activity of glutamine synthetase (GS), phosphate activated glutaminase (PAG), superoxide dimutase (SOD) and the concentrations of glutamate (Glu), lipidperoxide(LPO) were determined. Results The concentrations of iAs, MMA and DMA in the blood and brains increased as the iAsⅢ concentrations in drinking water increased. The activity of GS, PAG and the concentrations of Glu in the arsenic exposed mice increased compared with the control. The activity of GS in 50 mg/L group, the activity of PAG in 25 and 50 mg/L groups, the concentration of Glu in 100 mg/L group showed a significant difference compared with the control. The activity of PAG in 25 mg/L group was significantly higher than that in 100 mg/L group. The activity of SOD in exposed groups was higher than that in the control, the concentration of LPO in exposed groups did not show a significant difference compared with the control. Conclusion Arsenic can enter the brain and organic arsenic is dominant both in the blood and brain, however, the composition of arsenic speciation is different in the blood and brain. DMA, as a main arsenide, distributed in the brain. Arsenic exposure can change the activity of GS and PAG which can influence the concentration of Glu. Moreover, arsenic exposure can increase the superoxide anion and make the activity of SOD increase compensatively.

Objective To assess the ability of pixel-based quantitative evaluation of CT values in differentiating benign and malignant cystic-solid ovarian tumors.Methods CT images of 41 cystic-solid ovarian lesions from 39 patients were reviewed,with 27 benign and 14 malignant confirmed by post-operation pathology or follow-up.Regions of interest (ROIs) were drawn along edges of tumors on all slices of contrast-enhanced images with ImageJ software.CT values of each pixel were extracted.CT values of 20,25,30,35 and 40 HU were used respectively as the threshold to divide cystic and solid components.Solid proportion,the mean and median CT values of solid component were calculated and compared between benign and malignant groups.Results Mean CT values of solid components were all higher in malignant than in benign ovarian masses under all the threshold values (P<0.05).For median CT values, the same trend existed under the threshold of 20,25,35 and 40 HU (P<0.05).For the solid proportion,difference was found only under the 40 HU threshold, with lower value in malignant group (0.67±0.25) than in benign group (0.47±0.31).ROC curves were drawn to differentiate benign and malignant lesions.The highest AUC was obtained by using the mean CT value of solid components defined by 40 HU threshold (AUC=0.735).Conclusion Pixel-based quantitative evaluation on CT images could help to define cystic and solid components of ovarian masses, with 40 HU to be an optimal threshold.Cystic-to-solid proportion and CT value of solid components derived from whole lesion can help to differentiate benign or malignant lesions.

Objective:To investigate the expression of Survivin and programmed cell death 5(PDCD5)protein in mucoepidermoid carcinoma(MEC).Methods:Survivin and PDCD5 were detected by immunohistochemical staining in 20 cases of normal parotid tis-sue(group A),40 cases of pleomorphic adenoma(group B)and 45 cases of MEC tissues(group C).Results:The positive expres-sion ratio of Survivin in group A,B and C was 10.0%,27.5% and 55.6% respectively(χ2 =14.556,P <0.01),while that of PD-CD5 was 85%,65% and 33.3% respectively (χ2 =17.439,P <0.01).The expression of survivin or PDCD5 was related with dif-ferentiation,lymph node metastasis and TNM staging of MEC.Survivin and PDCD5 showed a negative correlation in MEC(χ2 =4.500,P =0.034,γs =-0.316).Conclusion:Survivin over-expression and PDCD5 down-expression may play a role in the de-velopment and progress of mucoepidermoid carcinoma.

Objective To study the effects of different factors on the salvianolic acid B stability in water solution and to provide the experimental data for production and application of salvianolic acid B. Methods Effects of salvianolic acid B concentration, pH value, temperature, and holding period on salvianolic acid B stability in water solution were studied by the salvianolic acid B changes determined by HPLC in orthogonal design test. Results The most stable condition of salvianolic acid B is that the concentration is 1 mg/mL, pH value is 2, the temperature is 20℃ , and the holding period is one day. Conclusion Salvianolic acid B should be kept in the conditions of higher concentration, lower pH value, lower temperature, and shorter period in solution to ensure its stability.

0.05). Compared with group A, GMBF of group C, D, and E were reduced (P0.05). CONCLUSION: Hepatic portal interdicting can aggravate the gastric mucosa damage of the liver cirrhosis rat, and famotidine can protect against such gastric mucosa injury through improving the microcirculation of gastric mucosa.

AIM: To construct HBx eukaryotic expression vector pEYFP-C1-X and eukaryotic expression vector pGL3-P4 driven by P4 promoter of human IGF-II gene and to investigate the effect of HBx on the transcription activity of IGF-II gene P4 promoter. METHODS: HBx gene and P4 promoters were cloned into pEYFP-C1 and pGL3-basic vectors respectively by gene recombination techniques to construct recombinant plasmids pEYFP-C1-X and pGL3-P4. HepG2 cells were transfected with pEYFP-C1-X and the resistant cell clones were selected by G418. Then methylated pGL3-P4 was transiently transfected into the above cell clones, and the transcription activity of P4 promoter was determined by dual-luciferase reporter assay system. RESULTS: (1) Aim fragments HBx gene and P4 promoter that were cloned were 465 bp and 1 246 bp, respectively and the DNA sequences were accordant with GenBank data confirmed by restricted enzyme digestion and sequencing. (2) HepG2-EYFP-X cells that expressed HBx protein were obtained. (3) Luciferase activity of methylated P4 promoter in the HepG2-EYFP-X was more than that of control cell HepG2-EYFP (P<0.01). CONCLUSION: HBx may enhance the transcription activity of the P4 promoter.

Objective:To measure the real temperatures on the pluggers of three continuous-wave de-vices, and to provide theoretical reference to evaluate thermal damage and heat ’s influence on the filling materials.Methods:The dual channel K type thermocouple was contacted to various sizes ’ pluggers in three different continuous-wave devices (BeeFill, Elements, B&L), and the highest temperatures at dif-ferent points ( tip, and 2 mm, 5 mm, 10 mm from the tip) of the pluggers ( preset temperature was 200℃) were recorded.The measurements were performed 5 times.T-test was used to compare the real tem-peratures at the tips with that set on the display and one-way ANOVA was used to compare the tempera-tures of the pluggers in different devices , sizes and points .Results:The highest temperature was at the tip of BeeFill 40/0.03 plugger (198.7 ±7.7) ℃, but there was on statistical differences between that and the preset temperature 200℃.The temperatures of the remaining pluggers were obviously lower than 200 ℃(P<0.05).The lowest temperature of the pluggers was detected at 10 mm from the tip of BeeFill 60/0.06 plugger (69.9 ±4.0) ℃.The highest temperature of each plugger was detected at the tip or 2 mm from the tip (112.1 to 198.7℃,and the median was 140.8℃).Conclusion:The real temperature of most continuous-wave pluggers included in this study is below the set temperature 200 ℃.

OBJECTIVE To implement the automatic management of medical equipment.METHODS Based on the platform of net,three layers of C/S were applied with database technology to realize one-time importation of the basic information and current information,it made the information function of quantity evaluation,quantity determination,schedule formation,automatic alarm,apparatus distribution list,statistical inquiry,collection analysis,and information feedback coming to true.RESULTS By using one year,the application of management information system of medical equipment could meet the requirement in scientific and standardized supply,and standard,application and management of medical equipment.CONCLUSIONS It can be able to improve the system efficiency,reduce the labor and mistakes,and also achieve the aim that cannot be done by manual labor.

Background Researches showed that platelet-derived growth factor (PDGF) modulate the expression of matrix metalloproteinase/tissue inhibitor of metalloproteinase (MMP/TIMP) in cells,but the association of expression of MMP/TIMP in retinal pigment epithelial (RPE) cells and the dose and active time of PDGF is unclear.Objective This study was to observe the effects of PDGF on the expressions of MMP-2,MMP-9 and TIMP-1 in cultured RPE cells in vitro.Methods RPE cell line,ARPE-19,was calculated in vitro,and the cells were divided into 5 groups when they reached 70％-80％ confluence.Different concentrations (0,0.1,1,10,50 mg/L) of PDGF was added into the medium respectively for 36 hours,and the expressing levels of mRNA and protein of MMP-2,MMP-9 and TIMP-1 were detected by reverse transcription PCR (RT-PCR) and Western blot assay.In addition,RPE cells in PDGF group were treated with 10 mg/L PDGF for 24,36,48 hours respectively to detect the expressions of mRNA and protein of MMP-2,MMP-9 and TIMP-1 in the cells and to compare with the control group without PDGF.Results PDGF stimulated proliferation of RPE cells in a dose-and time-dependent manner.As the increase of the PDGF concentrations,the expression values of MMP-2 mRNA and MMP-9 mRNA in RPE cells were gradually elevated,with a statistically significant difference among various groups (MMP-2 mRNA:F=79.304,P=0.000;MMP-9 mRNA:F =8.465,P=0.003),and the expressions of MMP-2 mRNA and MMP-9 mRNA were significantly higher in the 1,10,50 mg/L PDGF groups compared with 0 mg/L PDGF normal control group (all at P＜0.05).Also,the expression values of MMP-2 and MMP-9 proteins in RPE cells were gradually elevated with the increase of PDGF concentrations,showing statistically differences among the groups (MMP-2:F=26.550,P=0.000;MMP-9:F=80.993,P=0.000).Compared with the 0 mg/L PDGF group,MMP-2 and MMP-9 expression levels in the 1,10,50 mg/L PDGF groups were significantly up-regulated (all at P＜ 0.05).However,the expression levels of TIMP-1 mRNA and protein group in the cells were not significantly different among various groups (mRNA:F =0.143,P =0.962 ; protein:F =1.955,P =0.178).The expression levels of M MP-2 mRNA,M MP-9 mRNA in the cells were increased in the PDGF group compared with the control group at different time points (MMP-2 mRNA:Ftime =83.250,P=0.002 ; MMP-9 mRNA:Ftime =6.785,P =0.019).Also,the expression values of MMP-2 and MMP-9proteins in RPE cells were increased in the PDGF group compared with the control group at different time points (MMP-2:Ftime =1 l.185,P =0.041 ; MMP-9:Ftime =968.413,P =0.000).The expression levels of MMP-2 and MMP-9 mRNAs and proteins were significant between the two groups at different time points (all at Pgroup =0.000;all at Ptime＜0.05).While the expression changes of TIMP-1 werc not significant between the two groups and among various time points (all at P＞0.05) Conclusions PDGF up-regulates MMP-2 and MMP-9 expressions in RPE cells in a dose-and time-dependent manner.But,PDGF dose not alter the expression of TIMP-1.These results indicate that PDGF disrupt the balance of MMP/TIMP,which may damage the extracellular matrix and therefore facilitate the migration of RPE cells in the pathogenesis of proliferative vitreoretinopathy.

Breast cancer is the most common cancer in female population. Early detection of breast lesions and proper differentiation will directly impact on clinical treatment strategy and is related with prognosis. Breast tumors are usually rich in vascularity. Contrast-enhanced spectral mammography (CESM), based on K-edge effect of iodine, can acquire images of iodine contrast distribution in breasts through special computing and subtraction of images with both low- and high-energy X-ray exposures after intravenous induction of iodinated contrast media. It can eliminate the disturbance caused by overlapping breast tissues and demonstrate blood supply of the lesions, thus is sensitive to small lesion, more accurate in tumor delineating and able to help diagnosing. The current clinical applications and progresses of CESM were reviewed in this article.