Purpose: To explore the telomerase activity in the malignant process of BALB/c-3T3 cells induced by crystalline nickel sulfide, nickel chloride. Methods: TRAP-sliver staining assay was used to detect the telomerase activity. Results: Telomerase activity in BALB/c-3T3 cells transformed by nickel sulfide and nickel chloride were all positive. Conclusion: The positive expression of telomerase activity in the cell transformation might be related to the nickel carcinogenesis.

Purpose: To study whether sesquiterpene lactones(SLs) have the inducible apoptosis effect on human nasopharyngeal carcinoma (NPC) and it's relation with the mechanism of caspase activation, Methods: NPC cell line (CNE1) was treated with parthenolide(PN),the principal active component of SLs. The apoptotic cell death was indicated by morphological alterations. The inducible apoptosis and cytotoxicity effect were determined by flow cytometry, and the cellular caspase－9 and caspase－3 activity was measured by a spectrofluorometric method. Results: The TUNEL positive cell (％) and the SubG1 (％) of cell cycle distribution in creased in PN treated group. Compared with the negative control, there were significant increases of detached cell ratio (％) and lactate dehydrogenase (LDH) leakage (％). However, after PN treatment, the activities of caspase－9 and －3 were not significantly increased. Combined with caspase inhibitors in blocking experiment, PN decreased the caspase－9 and －3 activity but not the apoptotic and cytotoxic index. Conclusion: It was indicated that PN is able to induce apoptosis of CNE1 cell, which may be correlated with cytotoxicity effects but not with caspase cascade activation.

Purpose: To investigate DNA damage of human lymphocytes after treated with H2O2. Methods: Comet assay was employed to assess DNA damage of human lymphocytes treated with either various concentrations of H2 O2 (0、10、20、40、80 μmol/L) for 20 minutes or 20 μmol/L H2O2 for different time (0、10、20、30 minutes). To quantify the DNA damage, three different comet parameters were evaluated: the tail length, comet length and tail moment. Laser scanning confocal microscope (LSCM) was also introduced to investigate the 3-D distribution of DNA within the comet. Four fluorescent dyes including propidium iodide (PI), ethidium bromide (EB), acridine orange (AO) and Hochest33258 were compared. Results: The tail moments (-±s) were 0.001±0.002、0.31±0.35、1.23±0.96、2.82±1.38、3.52±0.96(P<0.01), respectively, after treatment with various concentrations of H2O2(0、10、20、40、80 μmol/L); the tail moments(-±s) were 0.05±0.09、0.22±0.30、1.62±0.93、1.89±1.09 (P<0.01), respectively, after treatment for different time(0、10、20、30 minutes ). Tail length and comet length also exhibited significant increases (P<0.01) with the increased dose and extended time. The 3-D reconstruction made by LSCM gave a more distinct image of the comet compared with the fluorescence microscope. PI and EB were better dyes in terms of the definition of the image. Conclusion: H2O2 induces dose-dependent and time-dependent cytotoxic effect in terms of DNA damage on human lymphocytes. The LSCM provides substantial and measurable improvement in the definition of the“comet". PI and EB are suitable for comet assay.

Purpose: To construct pEgr-P16 plasmid and detect its expression in esophageal squamous EC9706 cells induced by irradiation. Methods: Human P16 cDNA was ligated to downstream of Egr-1 promoter to construct pEgr-P16 plasmid. The recombined plasmids were transfected into EC9706 cells with liposome. The expression of P16 after different doses of γ-ray irradiation was detected by Westernblot technique. Results: Restriction enzyme digestion showed pEgr-P16 was correctly constructed. The P16 expression in cells transfected with pEgr-P16 induced by different doses of irradiation was higher than that of sham-irradiation group. Conclusion: γ-ray can induce and enhance expression of pEgr-P16 plasmid in EC9706 cells.

Purpose: To investigate the antitumor effect and possible mechanism of AC-88. Methods: Tumor bearing mice were used as model in vivo to study the an titumor effect of AC-88. T cell proliferation was determined by using MTT method. The changes of TNF-α、 IL-1β、 IL-6 mRNA content in T cells were measured by RT-PCR. Results: The antitumor rate of AC-88 was 76 ％. Treatmemt with AC-88 significantly enhanced T cell proliferation, and increased contents of TNF-α,IL-1β,IL-6 mRNA in T cells by 2-4 folds compared with that in control(P< 0.01) . Conclusions: AC-88 can inhibit the growth of tumor and regulate the T cell function in tumor bearing mice, which is worthy to be developed into an anticarcinogen.

Purpose：To provide some scientific basis for the revealment of neurotoxic mechanism of lead ,The present study was undertake to the effect of lead acetate on the apoptosis and the expression of P53. Methods: Mature and health Sprague- Dawley rats were divided into four groups randomly, six rats in every group. Lead acetate was given at the dosage of 25,50,100 mg/kg through ip for 5 days, respectively . The determination of apoptosis in hippocampus and cerebral cortex was made by terminal- deoxynucleotidyl transferase mediated d- UTP nick and labeling(TUNEL). The expression of P53 genes in hippocampus and cerebral cortex was observed by using immuno- histochemical method . Results: The results of TUNEL showed that lead acetate induced apoptosis f cells from hippocampus, cerebral cortex in every treatment group (P < 0.05), and there was a significant dose- response relationship.The expression of P53 increased in neural cells from hippocampus, cerebral cortex in every lead acetate treatment group compared with the control , and there was a significant dose- response relationship. Correlation analysis demonstrated that the apoptosis were positively correlated with the expression of P53. Conclusion: Lead may elicit apoptosis of rat neural cells from hippocampus, cerebral cortex , and the apoptosis was positive correlative with the lead dosage. Lead acetate may promote the expression of P53 genes， and there was a good dose- response relationship。 The results above suggested that P53 as a regular factor of apoptosis， may participate in the neurotoxical damaging to the central nervous system by lead. The overexpression of P53 induced the apoptosis of neural cells. Lead acetate may initiate the expression of P53 followed by he apoptosis of neural cells .

Purpose : To study the inhibitive effects of green asparagus juice and extracts on nucleic acid biosynthesis of mouse sarcoma S180 cell and mouse Ehrlich ascitic tumour cell. Methods:The inhibition rates of the nucleic acid biosynthesis in tumour cells were investigated with 3H-TdR and 3H-UR incorporation DNA and RNA， respectively. Results:As treated with different doses of the juice and alcohol extracts of green asparagus (20，40，80，160 mg/ml), the inhibitive rates of S180 DNA were 20.40 ％，52.19 ％，56.90 ％，77.11 ％ for the juice and 53.25 ％ ， 76.86 ％ ， 88.86 ％ ， 94.62 ％ for the alcohol axtracts . The inhibitive rates of S180 RNA were 24.70 ％，41.53 ％，76.06 ％，85.72 ％ for the juice and 60.17 ％，80.90 ％，94.08 ％，97.26 ％ for the alcohol axtracts； the inhibitive rates of EAC DNA were 5.16 ％，13.00 ％，31.44 ％，57.09 ％ for the juice and 20.56 ％，43.02 ％，58.55 ％，75.99 ％ for the alcohol axtracts；the inhibitive rates of EAC RNA were 10.52 ％，23.04 ％，45.60 ％，68.39 ％ for the juice and 13.37 ％，32.60 ％，59.70 ％，81.85 ％ for the alcohol axtracts respectively . Conclusion:The juice and the alcohol extracts of green asparagus all could induce the significanly inhibit the biosynthesis of DNA and RNA in tumour cells, and the inhibition was enhanced with the increase of the concentration of the juice and extracts .The results showed that the inhibition effect of alcohol extracts was obviously greater than that of the juice within a concentration range of 20 to 160 mg/ml.

Purpose: To explore the relationship between Fas/FasL expression in squamous cell carcinoma, basal cell carcinoma or cell apoptosi. Methods: Fas/FasL expression and cell apoptosis were studied in 45 patients suffering from squamous cell carcinoma or basal cell carcinoma by immunohistochemistry and terminal deoxynucleotidyl transferase-mediated dUTP-DIG nick end labeling (TUNEL). Results: Fas/FasL expression in squamous cell carcinoma was higher than in basal cell carcinoma. The apoptosis rate of Fas/FasL positive cells was higher than that of Fas/FasL negative cells. Conclusion: Fas/FasL system was rather associated with cell apoptosis and may play an important role in tumor invasion.

Purpose: To investigate expression of PTEN mRNA in endometrial carcinoma and its clinocopathoopoology. Methods: The expression of PTEN mRNA was detected by reverse transcription-PCR in 65 endometrial carcinomas and 15 normal human endometria. Results: Of the 65 endometrial carcinoma cases, the loss of expressions of PTEN mRNA in exon 1-8 , exon 5-9 and exon 5-8 were 49.23 ％，38.46 ％ and 32.31 ％， respectively. Expressions of PTEN mRNA was detected in all of the normal endometrial tissues. The lost rate of expression of PTEN mRNA was significantly relevant to histological type and histological grade in endometrial carcinoma. Conclutions: There was a higher incidence of negative expression of PTEN mRNA in endometrial carcinoma, which indicates that PTEN gene inactivation may play an important role in the genesis and development of some endometrial carcinoma .

Purpose:To study the breaking effects of Cisplatin, Carboplatin and Dicycloplatin on pBR322 plasmid DNA. Methods:Agrose gel electrophoresis and Gel image analysis was used. Results:All three platinum-species drugs could cause DNA break of pBR322 plasmid. The FC50 of Cisplatin, Carboplatin and Dicycloplatin were 33.71 μmol/L, 3.31 mmol/L, and 1.61 mmol/L , respectively. Conclusion:Breaking effects of tested drugs: Cisplatin > Dicycloplatin > Carboplatin.

Purpose: To study the clinical significance of the expression of telomerase activity in sputa of lung cancer patients. Methods: The sputa of 30 lung cancer patients and 25 benign lung disease patients(control group) were checked for telomerase activity with PCR-TRAP ELISA. Results: The positive rates of telomerase activity in sputum was 56.7 ％(17/30) in lung cancer group and 24 ％(6 /25) in control group. The difference is statistically significant(P< 0.05). Conclusion: The detection of telomerase activity in sputum of lung cancer patient is helpful for not only the diagnosis of lung cancer but also the differential diagnosis with other benign lung diseases. The assay method is comparatively convenient and nontraumatic, and the specimen is easy to collect.

Purpose: To study the clinical significance of expression levels of P53、Rb、P16 and P21 in cancer tissues. Methods: Flow cytometric analysis was used to detect abnormal expression of P53,Rb,P16,P21 in cancer tissues obtained from the 30 patients with ovarian carcinoma or breast cancer. Results: The expression levels and abnormal expression rates of P53、Rb、P16 and P21 in ovarian carcinoma were not differ from that in breast cancer.The abnormal expression rates of P53,P21,P16 and Rb in 30 cases were 40 ％, 66.7 ％ ,53.3 ％ and 53.3 ％ ,respectively. The rate of co-expression of two or more of them was 76.7 ％; 96.7 ％ (29/30) of tumors showed abnormalexpression of at least one item. Patients with abnormal expression of two items or more have clinical metastasis easily. Conclusion : Combination detection expression levels of P53,P21,P16 and Rb in cancer tissues , and comprehensive analysis of these parameters can be helpful to identify biological behavior of tumor and predict the prognosis .

Purpose: To study the relation between chromosome damage induced by cyclophosphamide(CP) and the expression of mutated P53 gene. Methods: The expression of mutated P53 gene in human lymphocytes was investigated using flow cytometry.And the micronucleus(MN) and sister chromatid exchange (SCE) tests were studied in vitro. Results: The expression ofmutated P53 gene in human lymphocytes treated with CP was 30.81 ％, (P < 0.01)compared with the control .The frequencies of SCE and MN in human lymphocytes exposed with CP were 9.21±1.08 and 8 ‰ respectively(P < 0.01),compared with the control. Conclusion: The mutagenic effect of CP may be related to the expression of mutated P53 gene .

Purpose:To observe the influence of herba loenuri on the genetic damage induced by Pb(CH3COO)2 in mice. Methods:The micronucleus test of mouse bone marrow cell and sperm abnormality test in mice were used in this study. Results: Herba loenuri could not induce either micronucleus formation in the mouse bone marrow cells or sperm abnormality in mice, but the frequencies of micronucleus formation in the mouse bone marrow cells and sperm abnormality in mice indued by Pb(CH3COO)2 were reduced significantly if herba loenuri and Pb(CH3COO)2 were given stimultaneously. Conclusion: Herba loenuri showed a protective effect ,namely antimutagenesis ,on genetic materials in mice.

Purpose: This study was undertaken to determine the potentially teratogenic effects of pioglitazone hydrochloride to Wistar rats. Methods: The study was conducted with three groups orally administered with 6, 24, and 96 mg/kg doses continuously for 10 days from 6th to 15th day after gestation of rats. Positive (2 mg/kg Dikushuang) and negative controls (0.5 ％ CMCNa) were performed at the same time with the method. Results: the number of absorptive embryo and dead fetus increased in the high dose group (96 mg/kg). The stunt effect of pioglitazone hydrochloride to the fetus was observed in all dose groups. Conclusion: Pioglitazone hydrochloride showed obvious embryo toxicity, but no teratogenic effect to fetus was observed.

Purpose and methods : The potential mutageni city of arginine esterase from Agkistrodon halys ussuriensis venom was studied by Ames test, micronu cleus test of polychromatic erythrocytes in bone marrow and sperm shape abnormality test in mice to evaluate its safety for clinical application. Results and conclusion: The results of all the three testes were negative. It was suggested that the arginine esterase is not mutagenic to the tested strains, to the somatic cells and to the male germ cells. If Its gene mutagenesis was considered as an important factor, arginine esterase is still safe at the dosage of about 100 times clinical dosage.

Purpose: To study the acute toxicity and the mutagenicity of Chuanbeipiba polysaccharides. Methods: The oral acute toxicity tests in rats and mice, Ames test, micronucleus test of polychromatic erythrocytes in bone marrow and sperm shape abnormality test were carried out. Results: LD50 in rats and mice were more than 10 g/kg; The micronucleus rates and sperm abnormality rates in all doses were not significantly different from the control group(P>0.05), respectively. But those rates in positive group were higher than in the negative control group(P<0.01).No increase in the number of revertant colonies was found in the Ames test with and without S 9 mix Conclusion: Acute toxicity and the mutagenicity of Chuanbeipiba polysaccharides were not observed in this study.