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More and more attention has been paid to the research and application of 3D map as 3D map products visualization conductive to perceive geographic environmental information more intuitively and more clearly. The research on 3D map symbol is one of the core technologies. The data structure and modeling method of the 3D map symbol were studied in this paper. We could get the good expression of 3D symbol by using rational data organization and classification and by using several modeling methods, for instance, modeling directly based on mathematical description and modeling based on VRML. One 3D map symbol library was developed according to the models above. Such library had several functions such as model classification management, real-time construction and edit of model symbol, and management and maintenance of symbol library. And the library had got a good result in application.

It has been reported that phospholipase C-gamma1 (PLC-gamma1) plays an important protective role in hydrogen peroxide (H(2)O(2))-induced pheochromocytoma (PC) 12 cells death. However, most studies have used high doses of H2O2 and the downstream targets of PLC-gamma1 activation remain to be identified. The present study was designed to examine the roles of PLC-gamma1 signaling pathway in the apoptosis of PC12 cells induced by low dose of H(2)O(2), as well as the downstream factors involved in this pathway. Low-dose treatment of H(2)O(2) resulted in PLC-gamma1 tyrosine phosphorylation in a time-dependent manner and H(2)O(2) killed the PC12 cells by inducing necrosis. In contrast, pretreatment of PC12 cells with U73122, a specific inhibitor of PLC, markedly increased the percentage of dead cells. The mode of cell death was converted to apoptosis as determined by Hoechst/PI nuclear staining and fluorescence microscopy. Western blot analysis demonstrated that the expression of Bcl-2 protein and the activation of pro-caspase-3 were not significantly affected by low dose of H(2)O(2) alone. However, after pretreatment with U73122, Bcl-2 protein expression was dramatically decreased and the activation of pro-caspase-3 was significantly increased. We concluded that PLC-gamma1 plays an important protective role in H(2)O(2)-induced PC12 cells death. Bcl-2 and caspase-3 probably participate in the signaling pathway as downstream factors.

To explore the role of phospholipase C-gamma1 (PLC-gamma1) signaling pathway in H(2)O(2)-induced apoptosis of PC12 cells.PC12 cells were exposed to 50 micromol/L H(2)O(2) after pretreatment with 10 micromol/L U73122, a specific PLC-gamma1 inhibitor. Hoechst/PI double staining was performed to observe the morphological changes of the cells under light microscope. MTT assay was used to evaluate the cell viability, and the percentage of apoptotic cells was analyzed by flow cytometry. DNA fragmentation assay was carried out to characterize the cell apoptosis.After inhibition of the PLC-gamma1 signaling pathway with 10 micromol/L U73122, PC12 cells showed obvious apoptotic morphology, the viable cells decreased significantly, and the percentage of apoptotic cells rose to 35.7%. PC12 cells treated with U73122 presented with a distinct DNA ladder on electrophoresis resulting from DNA cleavage in the apoptotic cells.PLC-gamma1 signaling pathway plays an important protective role in H(2)O(2)-induced PC12 cell apoptosis.

Genetic factors are known to be important in the development of esophageal squamous cell carcinoma (ESCC). Epidermal growth factor (EGF) can activate several signaling pathways leading to proliferation, differentiation, and tumorigenesis of epithelial tissues by binding with its receptor. Interindividual variations in EGF production were genetically contributed to EGF +61 G/A polymorphism. The purpose of this study is to investigate the potential association between EGF gene polymorphism and ESCC in a Chinese population. In this study, we analyzed single nucleotide polymorphism of EGF +61 G/A in 158 patients with ESCC and 212 age- and sex-matched controls in a Chinese population using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy and DNA sequencing. The variant genotypes of GA/AA were associated with a significantly decreased risk of ESCC compared with the wild-type homozygote GG (OR = 0.657, 95% CI: 0.434-0.996). However, no significant difference was observed between the EGF +61 G/A polymorphism and the risk of ESCC when the analyses were stratified in terms of age, gender, smoking status, different clinical stage, and lymph node status. The EGF +61 G/A polymorphism is associated with ESCC in a Chinese population. Our data suggests that the EGF gene may play a role in the development of ESCC.