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Objective To observe the expression of the polysialic acid neural cell adhesion molecule ( PSA-NCAM) in the hippocampus of rats after exposure to low intensity ( 16 Hz,90 dB) infrasound for different periods.Methods One hundred and twenty male Sprague-Dawley rats were randomly divided into infrasound exposure and normal groups.The exposure group was tjem further divided into 1 day,7 days,14 days and 21 days exposure groups.After exposure,the rats' brains were removed and an immunohistochemical technique was used to observe the expression of PSA-NCAM in the hippocampus after 1,7,14 or 21 days of exposure. Methods The expression of PSA-NCAM had increased significantly after exposure for 7 days. It peaked at 14 days,then had decreased by 21 days,but always remaining higher than in the normal group.After the infrasound exposure had ended,the expression of PSA-NCAM demonstrated a tendency of decrease over time,and the least was on the 21st day.The largest decrease was observed in the 14 days exposure groups. Conclusion 16 Hz,90 dB infrasound can increase the expression of PSA-NCAM in the hippocampus,at least in rats.This suggests that low intensity infrasound might initiate recovery of an injured central nervous system.Migration of neural stem cells may aid in the repair of neural injuries resulted from infrasound exposure.
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Objective:To investigate the inhibitory effect of the water-soluble preparation of curcumin on tumor angiogenesis induced by alginate-encapsulated colon carcinoma C26 cell line in mice. Methods: The water-soluble preparation of curcumin was made by forming inclusion compound of curcumin with hydroxypropyl-?-cyclodextrin (C-HP-?-CD). Subcutaneous imbedding of alginate-encapsulated colon carcinoma C26 cells was used to create tumor bearing model in BALB/c mice. Then the mouse models were intraperitoneally injected with C-HP-?-CD, TNF-70 (as positive control), or HP-?-CD(as negative control). The angiogenesis in the alginate beads was observed under light microscope, floresencent microscope, and transmission electron microscope. The fluorescein isothiacyanate-dextran (FITC-Dextran) tracing technique was used to observe the inhibitory effect of the inclusion compound of curcumin on angiogenesis induced by colon carcinoma C26 cells in alginate beads.Results: The C-HP-?-CD and the mouse model of subcutaneous alginate-encapsulated colon carcinoma C26 cells were successfully created. Transmission electron microscope showed angiogenesis in alginate-encapsulated colon carcinoma C26 cells; claval endothelial cells were seen in some lumens. Optical microscope and the fluorescence microscope showed that the angiogenesis density of the positive group and curcumin groups were obviously lower than those of the negative control group; no obvious difference at vessel morphosis was found among the 3 alginate-encapsulated groups. FITC-Dextran tracing technology found that the fluorescent intensity of the negative control group was significantly higher than those of the positive control group and the curcumin group (P