To study the mechanism of CAIMA (Computer assisted instant monitoring drug administration), atracurium, a new non - depolarizing muscle relaxant was used in isolated rat diaphragm. The doses and administration rate were precisely controlled by using an improved flowing-bath system. The results showed that with increasing drug concentration, onset time shortened,over-shoot time prolonged, initial recovery rate reduced and onset rate, over-shoot extent and recovery index increased. The over-shoot existed at any pharmacologically effective concentrations and it was positively correlated to drug concentration. As a result of need-dependent and intermittent (pulsatil) drug administration, one maximally profited effect from over-shoot, that is, the effect could be maintained with over-shoot at the administration interval. Hence, the total dose could be dramatically reduced. Furthermore, for a given effect, it needs lower drug concentration with CAIMA than with classical methods and so the effect was nuch more stable.

Objective: To investigate the effects of novel targeted non-viral vector in gene therapy of human glioma. Methods: The EGF-R targeting gene delivery system GE7 was constructed. Human Glioma cell line U251 was transfected in vitro with ?－gal as reportor gene and p21 as therapeutic gene using this gene delivery system. By means of the assay of ?-galactosidase staining, Western blotting, in situ end labeling apoptosis cells and DNA ladder, the transferring of exogenous genes and the apoptosis of the tumor cells were examined.Results: It was showed that gene transfer efficiency is over 80%. When transfected with p21 gene, the growth of cells was inhibited significantly, and the apoptosis was detected in the transfected cell by the methods of in situ end labeling and DNA ladder. Conclusion: The GE7 gene delivery system has the ability to transfer exogenous gene to tumor cells and the expression of the therapeutic gene can inhibit the growth of the cells.

Objective: Purpose to investigate the different in vitro function of targetable non-viral vector containing poly-L-lysine or protamine. Methods: Using GV1 and GV2 targetable non-viral vectors, the influences of the poly-L-lysine and protamine on in vitro gene transfer efficiency and the course of gene expression were observed. Results: ?-galactosidase was expressed at intermediate level (50% ) in A375 cells using a complex containing either protamine or poly-L-lysine. Howerver, in case of ABAE cells, ?－galactosidase expression level was low (20% ) transferred with a comPlex containing protamine. On the contrary, ?－ galactosidase expression was at high level (70% ) provided that protamine was replaced with poly-L-lysine. In addition, ?-galac- tosidase activity reached the peak at the 6th day after transfection with the complex containing protamine. The expression was not altered with subsequent subcultures, at least for 3 passages. Using poly-L-lysine, the expression peak in A375 reached the peak at the 7th day after transfection, but the level declined along with subsequent passages of cells. Conclusion: The apllication of protamine in VEGF receptor mediated gene delivery system was limited.

Objective To investigate gene transfer efficiency of a novel target non-viral vector GE7 and effects of herpes simplex virus thymidine kinase (HSV 1-tk)/ganciclovir(GCV) mediated by it in vitro. Methods The epidermal growth factor receptor (EGF-R) target gene delivery system GE7 was constructed.Human ovarian cancer cell line CAOV3 was transfected in vitro with ?-galactosidase(?-gal) as reporter gene and HSV 1-tk gene as therapeutic gene using this gene delivery system.By means of the assay of X-gal staining, Northern blotting, cell growth-inhibiting curve and so on,the transferring efficiency of exogenous genes and killing effects are observed. Results It showed that gene transfer efficiency is over 80%.When 10 mg/L GCV was put into ovarian cells transfected with HSV 1-tk gene, 95% of cells were killed, and the apoptosis ratio reached up to 30. Conclusions The GE7 gene delivery system is an effective and safe delivery system.GE7/ HSV 1-tk /GCV therapeutic gene system is appraising for ovarian cancer.