Objective To establish a candidate reference method for the determination of serum lithium based on ion chromatog-raphy and evaluate its analytical performance.Methods A simple sample treatment procedure,which can be remove the proteins and/or organics in human serum,has been developed for the determination of serum lithium.Method precision was evaluated with different concentration of fresh human serum and EQA sample RELA-A/B.Method accuracy was investigated with the recovery ex-periments in fresh human serum and RELA-A/B sample.Results The linear equation was Y =0.817 1X -0.001 3 with a correla-tion coefficient of 0.999 95 under the optimum experimental conditions,the detection limit (3S/N)for lithium was 6 μg/L and the imprecision was less than 1.0%.The results of the recovery experiments indicated that the recoveries were reasonable for the deter-mination of serum lithium,in a range of 99%-101%.Conclusion The candidate reference method of lithium was successfully es-tablished and which can be used for traceability and standardization.It may provide an effective way for routine testing of lithium traceable to the reference method/reference material.

Objective To investigate the inhibitory effect of X-linked inhibitor of apoptosis associated factor-1(XAF1) on xenograft growth in nude mice with hepatocellular carcinoma. Methods The models of xenografted nude mice with human hepatocellular carcinoma cell line SMMC7721 were established. Intratumor injection was performed on three tumor sites in each group of mice (n=5) with recombinant adenovirus Ad5/F35-XAF1, control virus Ad5/F35-Null at the same infective titre or PBS of the same volume every two days for two weeks. The volumes of xenografts in all nude mice were measured every three days, and the differences between Ad5/F35-XAF1 group and the other two groups were compared. The apoptosis of tumor cells was determined by in situ end-labeling TUNEL method, the expression of XAF1 protein and microvessel density (MVD) were detected by immunohistochemistry. Results Intratumoral injection of Ad5/F35-XAF1 significantly inhibited the growth of tumor xenografts with smaller tumor size, less tumor weight and lower MVD compared with those injected with control virus Ad5/F35-Null and PBS (P<0.05 or P<0.01). However, the apoptosis index and expression of XAF1 protein in Ad5/F35-XAF1 group were significantly increased compared with the other two groups (P<0.01). Conclusion Ad5/F35-XAF1 significantly inhibits xenograft growth in nude mice with hepatocellular carcinoma, which is probably associated with the effects of XAF1 inducing hepatocellular carcinoma cell apoptosis and suppressing tumor angiogenesis.

Objective Survivin is overexpressed in gastric cancer. However it not expressed in normal gastric mucosa. The expression of survivin is tightly related to the prognosis of gastric cancer.By gene reconstruction we generated pcDNA3 survivin mutant(Cys84Ala) plasmid, and observed its effect on the gastric carcinoma cell lines. Methods The survivin mRNA and protein expression levels were determined by reverse transcription polymerase chain reaction(RT PCR) analysis,Western blot and immunohistochemical staining respectively . Flowcytometry and acridine orange staning were employed to detect apoptosis. Results Overexpression of survivin mRNA and protein were detected in the gastric cancer cell lines. Inhibition of survivin by survivin mutant cDNA induced apoptosis,activated caspase 3 activity,cleaved PARP and promoted cytochrome C releasing in gastric cancer cells,and effectively sensitized gastric cancer cells to chemotherapeutic agents. Conclusion Inhibition of survivin may induce apoptosis in gastic cancer and sensitize gastric cancer cells to chemotherapeutic agents.Survivin targeted therapeutic protocol may potentially benefit gastric cancer therapy.

Objective To investigate the possible signal pathway of the apoptosis in gastric cancer cell lines(SGC 7901 and MKN 45)induced by arsenic trioxide. Methods TUNEL method was used to observe the influence of calcium antagonist, inhibitors of protein kinase C (PKC) and protein tyrosine kinase(PTK) on the apoptosis of gastric cancer cells induced by arsenic trioxide. Levels of cAMP, PKC and PTK were detected before and after the treatment with arsenic trioxide. Results Both PKC and PTK inhibitors could induce apoptosis of gastric cancer cell lines, also both of them had a cooperative action with arsenic trioxide in inducing apoptosis of gastric cancer cells, while calcium antagonist had no any effect on the apoptosis of gastric cancer cell lines. PKC and PTK levels decreased but cAMP level increased during the apoptosis of gastric cancer cells induced by arsenic trioxide ( P