This study developed a semi2quantitative method of telomerase activity. The method was based on the combination of TRAP assay and scintillation count assay (3 H2dCTP incorporation) . It was used to quantify telomerase activity in CNE2 cells and some tissue specimens. RNase2pret reated or heat2t reated cells were used as cont rols. The result s demonst rated that telomerase activity measured by this method was positive in CNE2 cells , and it could be clearly detected with as few as 10 cells. There was a linear correlation between the radioactive count and the telomerase activity. The telomerase activity of some tissue specimens were accordant with reported data. Telomerase activity of RNase2pret reated or heatt reated cells was negative , their radioactive counts were almost the same as lysis buffer cont rol. The variations within group and between groups were 11. 68 % and 20.99 % , respectively. This method was f ree of PAGE and radioautography , and hence simple and fast . The results could be obtained with one day. It showed high sensitivity , good specificity and repeatability.

In other to investigate the relationship between DNA2protein crosslinks (DPC) and human lung cancer , we have used a sensitive 125Ⅰ2postlabelling assay to detect the formation of DPC in tissues to various cell type of human lung cancer. The results were showed that DPC was increased in lung cancer tissues comparing with its neighbored normal tissues , suggesting that DPC may play a part in the development of lung cancer. No significance differences were observed in DPC of tissues between adenocarcinoma and epidermoid carcinoma , and in DPC of lung cancer tissus between smoker and non2smoker.

Aging2related changes have been evaluated in hepatic cytochrome P450 content in rat s by specific cytochrome P450 enzymes. To determine whether senescence is concerned with CYP3A activity , the activities of the SAM hepatic cytochrome P450 3A (CYP3A) were quantified in vit ro as erythromycin N2demethylation in microsomes prepared f rom SAM2R1 、SAM2P1 and SAM2P8 , espectively , at 7 、13 and 36 weeks of age in every animal group. We found CYP3A activity was decreased with advancing age in SAM2P1 and SAM2P8 . At 13weeks of age , CYP3A activity was about 39. 5 % lower ( t = 2. 525 , P < 0. 05) in SAM2P1 and about 43. 7 % lower ( t = 2. 24 , P < 0. 05) in SAM2P8 . Compared with 36 to 13 weeks of age these two groups , CYP3A activity was decreased approximately 71. 3 % ( t = 2. 84 , P < 0. 02) in SAM2P1 and 62. 9 % ( t = 3. 21 , P < 0. 01)in SAM2P8 . It w as no signif icant dif f erences f rom 7 to 13 weeks of age in SAM2R1 , but f rom 13 to 36 weeks of age , it w as decreased about 38. 2 % ( t = 2. 37 , P < 0. 05) ) . Taken together , the data suggest that CYP3A takes very important effect to senescence.

To elucidate the expression of Wilms’tumor gene (WT1) in various types of leukemia and its clinical implication. WT1 mRNA was detected in K562 cell line , 23 leukemia patient s (12AML patient , 3 ALL patient , 7 CML patient , 1 CLL patient . ) 2 lymphoma patient s in three stage , and 10 healthy subjects by using RT2PCR. WT1 mRNA expression was revealed in K562 cell line , 10 of 12 AML patient s , 2 of 3 ALL patients , 6 CML patient s in blast crisis. WT1 mRNA was undetecatable in 1 CML patient in accelerated , 1 CLL patient , 2 NHL in three phase and 10 healthy subject s. WT1 gene is expressed in early hematopoietic cells , it is closely related with acute leukemia , and supposed to be a new marker for monitoring MRD in acute leukemia.

By means of Ames test , the genetic toxicology of chlorination on drinking eater is evaluated. The result showed that the mutagenecity of water increased in all samples t reated with chlorine , while mutagenic potential was negative in source water samples not t reated with chorine. By adding Na2S2O3 to chlorinated water samples , there had less mutagenic activity. The antimutagenic potentials of Na2S2O3 in the chlorine water was dose dependent , the higher the mutagenicity of chlorined water , the better the beneficial effect of nasal. These indicated that the mutagenecity in chlorined water can be reduced by water t reatment process.

The genotoxicity of sodium nit rite and N-methylbenzylamine were detected. The result s showed that sodium nit rite and N2methybenzylamine did not induce acute genotoxicity ( P > 0. 5) ,but had a middle and long term genotoxicity. Exposed for long term , the gast ric ant rum and exophagus in the rat s showed different levels hyperplastic change ; and the per mil rate of micronuclei of marrow cells increased ; the thymus gland indexes lowered.

In this paper , the effect of genotoxicity , reproductive toxicity and embryotoxicity on the second hand smoking in mice were investigated by the animal experimental model. Kunming mice were divided randomly into various experimental groups. The animals were exposed by smoke in 4. 7g/ m3 、9. 4g/ m3 and 18. 8g/ m3 . The rusultes showed that the f requencies of bone marrow polychromatic erythrocytes micronucleus , bone marrow cell SCE , early spermatids MN , spermatogonia chromosome aberration and sperm aberration increased significantly with increase of smoke dose ( P < 0. 05 , P < 0. 01) , and both were positive correlation. Furthermore , in the female mice of middle and high dose group , the body weight gains of the pregnant mice were less than those of the const rast group and decreased survival rate of fetal mice , increased death rate of fetal mice , decreased mean body lenght and weight of fetal mice , increased maldevelopment mice of ocipital bone and sternum were also found in those two groups. Those result s indicated that second hand smoking has effect on genotoxicity , reproductive toxicity and embryotoxicity.

By using the micronucleus test , the mutagenicity of cyclophosphamide (CP) and cigarette smoking condense (CSC) in Chinese A loe ( A loe Vera L . V ar. Chinese Berger. ) and Garlic ( A llium S ativ um L . ) and the antimutagenicity of ext ract s of the plant s in V icia Faba were studied. The result s showed that the plant s or it s ext ract s had obvious antimutagenic potentials ( P < 0. 01) .

In this paper , vicia faba roof tip cells are attended by ext ract s of spirulina platensis in different concent ration alcohol , following , poison t readed by towin20 , to observe the rest rain of micronucleus effect s of vicia faba roof tip cells on towin20 , by ext ract s of spirulina platensis. From the angle of micronucleus effect s of vicia faba roof tip cell , by statistical analysis : The positive cont rol of poison t readed by towin20 compared with the negative cont rol P < 0. 01 ; Poison t readed by towin20 after attended by ext ract s of spirulina platensis in best concent ration alcohol compared with the positive cont rol P < 0. 01. Result showed that towin20 is a st rong mutagen to cause significant micronucleus effect s. But , the ext ract s of spirulina platensis has significant rest rain to micronucleus effect s of vicia faba root tip cell on towin20 . Further more , approach the function of spirulina platensis to prevent cancer on the original of oncology on cell level. In the mean time , this experiment has tentatively gained a simpler and easier method to ext ract the effective composition of spirulina platensis.

The mutagenicity of pulic health insecticides2areosol had been detected with the micronucleus test in vicia faba root tip cells. The f requency of micronucleus was 26. 78 ‰. Comparing with tap water group , there was the statistically , significant differences) ( p < 0. 01) and showed dose2effect relation ship. The micronucleus test in rat bone marrow cell was negative. The result s suggested that pulic health insecticides2aerosol had mutagenicity in this experiment .

Objective :To study the brain developmental toxicity of lead and it s relationship with cell proliferation and differentiation. Method :The rat embryonic midbrain micromass cult rue method was used to observe the effect of PbAc on brain cells proliferation and differetiation. Restults :The proliferation and differetiation of cultured cells were both inhibited by PbAc , and both effect s showed obvious dose2dependent decreases( P < 0. 05) . Concent rations of lead to inhibit cell proliferaion and differentiation by 50 % were 3. 69μmol ( ICp50) and 1. 03μmol ( ICd50) respectively. Conclusion :According to the standard of Flint , PbAc can be a specific inhibitor of rain cell differentiation , it s brain cell developmental toxicity is related to the inhibition of cell proliferation and ifferentiation.

We combined five endpoint s into a single 52day in vivo screening assay to identify est rogenicity of enosulfan. The endpoint s evaluated as markers of esrogenicity included the ratio of uterine weight/ body weight , uterine fluid imbibition , vaginal cornification incidence , uterine st roma cell proliferation and uterine epithelial cell height . The endosulfan were administered daily p. o. for 5 days to sexually mature ovariectomized female NIH mice. Compared with the five endpoint s of the three dosage groups of edosulfan (0. 5mg/ kg/ d ,1. 5mg/ kg/d and 3. 0 mg/ kg/ d) showed no significant difference and no significant dose2response. Thus , endosulfan has no est rogenicity under the experimental condition.

The positive mutagenic response to six chemicals and doubtable positive mutagenic response to two chemicals and negative mutagenic response to two chemicals were demonst rated by a spontaneous dark mutant (kmutant) , St rain T9171 , isolated from photobacterium phosphoreum T3 Spp. Mutagenic mutant has higher sensitivity to genotoxic chemicals as compared with conventional Ames test . It is possible to become a simple sensitive short-term bioloical test method for the detection to mutagenic compounds in environment .

This study sought to address the relationship of breast carcinoma with deletion of MTS1 gene. 17 of 47 cases showed MTS1 gene was deleted by multiplex - PCR. The rate of deletion of MTS1 gene was 36. 2 %.the rate of deletion in metastatic breast carcinoma of lymph node was 60 %(9/ 15) , that in nonemetastatic breast carcinoma of lymph node was 25 %(8/ 32) . There were significant differences in the rate of deletion of MTS1 gene between them , and between the rate of infilt rating type of breast carcinoma and the others. These suggest that deletion of MTS1 gene was associated with progression and type of breast carcinoma.

To study the role of grape procyanidin ( GPC) in radiotherapy t reatment for tumor , The mice inoculated sarcocarcinoma S180 was t reated by local irradiation , GPC feeding and irradiation + GPC respectivly. The tumor weight and other indexs were examined at 12th day after tumor inoculation. The resluts showed the average weight of tumor of mice in cont rol group was higher than that of in other groups , the inhibitory rate of tumor in the group of irradiation + high dose of GPC was higher than both group irradiation or GPC , and the WBC count of mice in irradiation group was lower than other groups. All differenees above are significant in statistics.It suggest s GPC has a improve effect to the radiotherapy of tumor.

The content of serum IgG、IgA and IgM , T Lymphocyte t ransformlation rate , and the positive rate of CD4 、CD8 and N Kcell were performed in 26 cases exposed low2dose radiation in 1966 and in 1971. The results indicated that the content s of serum IgG、IgA and IgM in the irradiated group were not more different than thatin cont rol ( P > 0. 05) ; the positive rates of CD4 、CD8 and N K cell were significantly lower ( P < 0. 05 , P < 0.01) , the value of CD4/ CD8 was much higher ( P < 0. 01) , the lymphocyte t ransformlation rate was lower (0. 05< P < 0. 01) in irradiared group than in cont rol. It is suggested the low2dose radiation can inhibit the cellular immune responses of the irradiated persons.

The concent ration and disappearance of the indor volatile organic compounds(VOC) was measured by chemical mothods under two model ornamented laboratory condition. The potential mutagenicity of VOCs was measured by the micronucleus test in vicia faba leaf tips. The result s showed that the VOCs in ornamental materials had the potential mutagenicity. The result s of micronucleus test had obvious relationship comparing with the genotoxicity of mouse. The moicronucleus test in vicia faba leaf s tips and mouse bone marrow cell suggested that human were safe coming into the new ornamental room after one month. This paper recommend the sanitation standard values of the air in new ornamental houses first of all in our count ry. Our study provided the sientific basis of establishing health standard for the department of health.

Three batches of rhEPO injections were studied on mutagenicity by Ames test and micronucleus test of PCE in mouse bone marrow. The Ames test result s showed that the reversion mutation f requencies of three batches of rhEPO injections with five doses ( 18. 75～300. 00 IU/ plate) didn’t increase in st rain TA97 , TA98 ,TA100 and TA102 with or without S9mix ; In 15000～60000 IU/ kg doses , the f requencies of micronucleus in bone marrow PCE cells of mice didn’tincrease. It showed three batches of rhEPO injections had no mutagenicity.