BACKGROUND ＆ AIM: DNA repair machinery plays an important role in the maintaining of genomic integrity.This study aims at investigating the changes of DNA repair gene expression pattern of malignant transformation of human bronchial epithelial cells generated by α particles exposure. MATERIAL AND METHODS:cDNA microarray chip was used to hybridize with the probes of Cy5 or Cy3 labeled cDNA from transformed BERP35T4 cells or parental BEP2D cells. The hybridized chip was scanned for fluorescent signals with ScanArray3000,the data were analyzed with ImaGene3.0 software. RESULTS:The expression patterns of total 126 DNA repair related genes were compared between BERP35T4 and BEP2D cells.Among the 126 genes,10 down_regulated genes and 3 up_regulated genes (DNA_PKcs, SMUG and RAD18) were identified in the transformed BERP35T4 cells.Those down_regulated genes function in the pathways of DNA double_strands break repair, nucleotide excision repair and base excision repair respectively. CONCLUSION: The DNA repair machinery was changed in the radiation_induced transformed cells,creating a scenery that could contribute to the acceleration of cellular malignant transforming process.

BACKGROUND ＆ AIM:The DNA adducts of the nonvolatile organic compounds (NOCs) in tap water were studied for further validating genotoxicity of NOCS and its mechanism at molecular level. MATERIAL AND METHODS:The sample of tap water derived from Donghu lake of Wuhan was collected and the nonvolatile organic compounds (NOCs) in water were concentrated on XAD-2 resin. The DNA adducts of such NOCs were examined by using 32P-postlabeling method. RESULTS：Some NOCs-DNA adducts could be found in biological samples including calf thymus DNA reacted with NOCs and liver of male mice treated with NOCs . CONCLUSION: DNA could be damnified by the NOCs in tap water directly， and the DNA adducts of such NOCs were formed in vitro and in vitro test.

BACKGROUND ＆ AIM： The characteristic and application of TOSC which is a biomarker related with antioxidant system were explored and compared with GSH, a general indicator of oxidative stress. MATERIAL AND METHODS： The NIH mice were divided randomly into groups, which were oral perfused by 0 mg/kg (saline control group) and 6.25, 12.5, 25 and 50 mg/kg paraquat (PQ) respectively. After exposure for 24, 48, 72 hours, TOSC values of livers, brains, hearts, kidneys and lungs of mice were measured. Correspondingly GSH of livers was determined at the same time. RESULTS: After scheduled exposure time for PQ, the levels of TOSC/mg protein in all experimental groups showed a faint decrease. However, the amount of liver GSH reduced obviously. CONCLUSION： TOSC was an integrated biomarker, which reflected actual status of organism's antioxidant system. Nevertheless, when showed the early damage of the oxidant, TOSC was less sensitive than GSH.

BACKGROUND ＆ AIM: Cytoplasmic dynein is a kind of microtubule-based related protein involving in many fundamental cellular process including organelles transport, spindles assembly and spindle checkpoint inactivity.To elucidate the effect of dynein dysfunction on oocytes meiosis process and the relative mechanism of premature oocytes, we observed the changes in oocytes maturation rate and its cyclinB1 gene transcription level after exposed to a known dynein inhibitor-sodium orthovanadate(SOV) in vitro. MATERIAL AND METHODS: The technique of oocytes cultured in vitro maturation(CVM)was employed to detect oocytes maturation rate. Single cell RT-PCR and semi-quantitative RT-PCR methods were applied to measure cyclinB1 mRNA level in oocytes. RESULTS: The maturation rates of oocytes were significantly different between 5 μmol/L SOV and control groups(P<0.05) and decreased with SOV increasing doses. However,the elevation of cyclinB1 mRNA level of immatured oocytes cultured for 12 h depended on SOV concentrations ranging from 50～500 μmol/L. In incontinuity SOV exposure experiments, the maturation rates of oocytes markedly reduced after first incubation with 400 μmol/L SOV at least for 1 h and first cultured in SOV-free medium for 4 h or 8 h then exposed to SOV (P<0.05).In time-course experiment, the opposite changes of cyclinB1 mRNA level of oocytes between SOV and control groups were observed. CONCLUSION: Dynein inhibitor might delay oocytes meiosis process, and cause the ectopic expression of cyclinB1inoocytes. The possible mechanism of meiosis arrest induced by SOV is related to dynein dysfunction and the abnormal transcription expression of cyclinB1 that caused changes of mature promoting factor (MPF) activity.

BACKGROUND ＆ AIM: To observe the expression of yeast cytosine deaminase (YCD) gene labeled by RFP in HeLa cells and how it mediates cytotoxicity. MATERIAL AND METHODS: YCD cDNA and RFP gene were cloned into Eukaryotic expression vector pIRES to construct YCD gene expression vector pIRES- YCD, then HeLa cells were transfected with pIRES-YCD in vitro. Expression of RFP gene in HeLa-Y cells was observed under a fluorescent microscope. The efficiency of transfection and the average intensity of fluorescence were analyzed by flow cytometry (FCM). The fluorescent cells were screened by FCM and were named HeLa-Y. The activity of HeLa-Y cells was detected by MTT colorimetric assay after they were treated with 5-FC at various concentrations.RESULTS: Expression of RFP gene in HeLa-Y cells was seen under the fluorescent microscope and HeLa-Y cells were screened by FCM. Apparently, the prodrug 5-FC killed HeLa-Y cells. There was logarithm cure relationship between 5-FC with HeLa-Y. CONCLUSION: These results demonstrate that RFP gene can be regarded as a reporter gene to screen the cells transduced with YCD quickly, and YCD/5-FC suicide gene system may prove helpful in gene therapy of cancer.

BACKGROOND ＆ AIM:To study the inhibition of telomerase activity in melanoma A375 cells by arsenic trioxide(As2O3).We analyzed the inhibition of telomerase activity in A375 cells by TRAP-ELISA and TRAP-PAGE-silver staining. MATERIAL AND METHODS: TRAP-ELISA and TRAP-PAGE-silver staining. RESULTS:As2O3 can inhibit telomerase activity in A375 cells and the rates of inhibition have both dose-dependent and time-dependent manner. CONCLUSION:As2O3 can inhibit telomerase activity in telanoma A375 cells.The TRAP-ELISA assay showed a dose-response and a time-response relationship for inhibition of A375 cells by As2O3 .The inhibition was enhanced with the increase of As2O3 concentration or prolong of co-culture time.

BACKGROUND ＆ AIM: To study the Influence of deltamethrin on the apoptotic rate and Bcl-2 expression of neural cells in rat. MATERIAL AND METHODS: Male Wistar rats were randomly divided into control group and four deltamethrin treatment groups at 5 h、24 h、48 h and 5 days after treatment of 12.5 mg/kg deltamethrin intraperitoneally.Apoptotic rate and Bcl-2 expression were measured by FACS420 Flow Cytometer; immunoblot was used to detect the expression of Bcl-2. RESULTS: Apoptotic rates in rat exposed to DM for 24 h、48 h and 5 d (Hippocampus:8.45±1.02、9.44±1.14、7.58±0.75；Cerebral cortex:7.90±0.49、8.01±0.87、7.97±0.41) were higher than those of the control(Hippocampus：2.97±0.36；Cerebral cortex：3.50±0.48);the expression of Bcl-2 of 5 h、24 h、48 h of hippocampus(5.27±0.33、4.72±0.13、5.80±0.86) and 24 h group of cerebral cortex(;cerebral cortex：4.27±0.48) decreased apparently comparing with that of the control group(Hippocampus：7.16±0.61;Cerebral cortex：6.99±0.66).CONCLUSION: DM can interfere with the apoptotic rate and Bcl-2 expression in rat brain.

BACKGROUND ＆ AIM: The purpose of this study was to estimate the diagnostic value of immumohistochemical methods for detection of lymph node micrometastasis, and to reveal the correlation between the lymph node micrometastasis and the clinicopathological finding. MATERIAL AND METHODS: We re_examined the presence of micrometastasis in 955 lymph nodes from 100 patients with PN0 disease who underwent curative esophagectomy. All lymph nodes were immunostained using an anticytokeratin antibody cocktail(AE1/AE3)and an antibody EMA. RESULTS: Micrometastasis was detected in 25 lymph nodes(2.63 ％)from 21 patients (21.21 ％). There was significant difference in detection of micrometastasis between immunohistochemical methods and routine method. Although there was no significant difference in detection of micrometastasis between the two antibodies, the antibody AE1/AE3 was better for detection than the antibody EMA. Lymph nodes containing micrometastases were widely distributed，and micrometastasis was not associated with the depth of invasion,the differentiation or sex. But the most frequently involved nodes were located at the lower thoracic carcinoma(P=0.006). CONCLUSION: Immunohistochemical detection of lymph node micrometastasis may be an indicator of lymphatic dissemination of tumour cells. The antibody AE1/AE3 can be a method for detection of lymph node micrometastasis. The presence of micrometastasis was associated with the location of oesophageal squamous cell carcinoma.

BACKGROUND ＆ AIM :To ascertain the reactivity of multi-antioxidants-ANTIOXIN selected and formed according to hypothesis "Multi-Antioxidant Chain" in hepatic microsomal and chemical modes of lipid peroxidation. MATERIAL AND METHODS: Lipid peroxidation was stimulated by CCl4,Vc/Fe＋＋ and cumene hydroperoxide(CHP)in hepatic microsomal models ,and superoxide anion free radicals(O2－.)were generated by assay of hydroxylamine competition and hydroxide free radicals(•OH) generated by Vc/Cu＋＋ in chemical models to determine reactivity of the antioxidants. The antioxidative activity of water- or/and ethanol-extracts,and multi-antioxidants were determined and selected by those models. RESULTS： The water-extracts of Chinese angelicae,Ginseng, Wolfberry fruit, Astragalus and Dangshen presented different inhibition on lipid peroxidation of microsomal models stimulated by CCl4, Vc/Fe＋＋，CHP and free radical models.The all water-extracts,except that of Ginseng presented weak inhibition on model generated by Vc/Fe＋＋ and that of Wolfberry fruit presented strongly stimulation on model generated by CHP,showed potent antioxidation in various models of lipid peroxidation and free radical.The extracts of herbal medicine showed inhibition on models of lipid peroxidation stimulated by CCl4、VC/Fe＋＋、CHP and model of oxygen uptake in dissimilar extent.The multi-antioxidants-ANTIOXIN came strongly forth inhibition on production of freeradicals in all models-selected. CONCLUSION： There were definite astriction of water-extracts or ethanol-extracts of Chinese angelicae,Ginseng,Wolfberry fruit,Astragalus and Dangshen used individually in antioxidation and scavenging free radical,and they showed distinct reactivity that was inhibition or stimulation on different model system.Those multi-antioxidants -ANTIOXIN selected and formed according to hypothesis-"Multi-Antioxidant Chain"had strong activity of antioxidation and inhibition on free radical in hepatic microsomal and chemical modes of lipid peroxidation.

BACKGROUND ＆ AIM: To test the hypothesis that antioxidant melatonin (MT) can reduce the incidence of phenytoin(DPH)induced teratogenesis. MATERIAL AND METHODS: Female Kunmin mice were administered by gavage with DPH,MT or DPH and MT simultaneously at GD6－15 after coitus and subjected to caesarean section for various examinations.RESULTS:There are any differences in mean corpora lutea,implants,absorptions,live pups and the dead rates among the different groups.The frequency of congenital defects in DPH-treated dams was dosage dependent,ranging from 18.2 to 45.0 ％.When MT was coadministered with DPH,there was a significant dose-related reduction(5 ％～12.24 ％)in fetal defects induced by DPH.Furthermore,MT can significantly antagonize the decreases of fetus length and pup weights induced by DPH. CONCLUSIONS:The antioxidant MT exhibited an excellent antagonism to the teratogenesis induced by DPH.

BACKGROUND ＆ AIM: To study the antitumor effect of Rhizoma Menispermi extracts and purify its'active component. MATRAIAL AND METHODS: The effect of Rhizoma Menispermi extracts on the proliferation of 12 kinds of tumor cell lines and 9 cases of tumor cell coming from patients were assayed in vitro using MTT colorimetric method.The antitumor active part of Rhizoma Menispermi extracts was separated and purified using three steps method. RESULTS: Rhizoma Menispermi extracts markedly inhibits the proliferation of 12 kinds of tumor cell lines, and with a dose-dependent relationship(P<0.01).Rhizoma Menispermi extracts also inhibits the proliferation of 9 cases of tumor cell coming from patients by primary culture.The antitumor active part was found. CONCLUSION: Both Rhizoma Menispermi extracts by water(RMW) and Rhizoma Menispermi extracts by ethanol(RME) have very strong antitumor effent in vitro；The effect of RME is stronger than RMW； PE2 is the antitumor active part of RME；PE2 not only has very strong and extensive inhibitive effect on the tumor cell lines but also has inhibitive effect on the tumor cell coming from patients by primary culture. It need the further development as antitumor drug.

BACKGROUND ＆ AIM:To investigate the expression of P73 gene in breast cancer, also to study the relationship among P73 gene,apoptosis and receptors of hormone. MATERIAL AND METHODS: The expression of P73 gene in breast cancer tissues was detected by RT-PCR and apoptosis by TUNEL. RESULTS：The expression of P73 gene was significantly higher in breast cancer(32/45) than in breast benign tumors(P<0.05)and significantly higher in positive metastasis of lymph nodes than in negative ones(P<0.05)；the expression of P73 gene was not associated with ER,PR,the apoptosis rate of P73 gene positive cells was not significantly different from the negative ones.CONCLUSION: The increased expression of P73 gene may be related with breast cancer.

BACKGROUND ＆ AIM:To investigate if the recombinant staphylokinase has the effect of mutagenesis. MATERIAL AND METHODS:Ames test,chromosomal aberration test in CHL cell and micronucleus test in mouse bone marrow were carried out. RESULTS:The recombinant staphylokinase at 0.7～40 mg/plate induced neither remarkable nor dose-dependent reverse mutagenecity to four auxotrophic mutants TA97, TA98, TA100 and TA102 with or without S9 mix. Concentrations between 1.25 and 5 mg/ml induced neither a dose-dependent nor significant increase in number of structural and numerical chromosomal aberrations with or without S9 mix.At 24 h after administration, the frequencies of micronucleated polychromatic erythrocytes in bone marrow of mice treated with recombinant staphylokinase between 125 and 500 mg/kg did not increase compared with the control mice. CONCLUSION:The recombinant staphylokinase has no effect of mutagenesis.

BACKGROUND ＆ AIM:To test the safety of minuteness granule calcium of biology as a kind of special food. MATERIAL AND METHODS: We obtained the results through acute toxicity test, micronucleus test of bone marrow cell,sperm shape abnormality test in mice and thirty days feeding tests. RESULTS: We fed SPF Kunming mice (female and male) minuteness granule calcium of biology, with the amount of 10 g/kg each time.There were no toxic phenomenon on animals within two weeks and no dead animals. According to the acute toxicity standard rules,the experienced object actually does not have toxic effects.In the experiment of micronucleus test of bone marrow cell and sperm shape abnormality test in mice,the result is negative respectively. In the thirty days feeding tests,the amount of the experienced object by which the female rat were fed are 1.71 g/kg as the low quantities,3.35 g/kg the middle and 6.82 g/kg the highest (as 26,50,102 times as the population recommended amount respectively);to the male rat,the amount are 1.82 g/kg as the low quantities,3.48 g/kg the middle and 6.99 g/kg the highest (as 27,52,105 times as the population recommended amount respectively).After the clinical test, blood test,biochemistry test,organisms weight and pharmacology test to the wistar rat,no obvious toxic effects have been observed. CONCLUSION: Minuteness granule calcium of biology is safe as a kind of special food.

BACKGROUND ＆ AIM: Study on the effect of market public para-dichlorobenzene mothball on the induced micronucleus of plant cells. MATRAIAL AND METHODS:Using the micronucleus test technique with Vicia faba leaves tip cells. RESULTS: With the same concentration of P-DCB mothball there was more micronucleus frequency with longer,which showed showed the time-effect relationship.With the same time there was more micronucleus frequency with more concentration,which showed the dose-effect relationship.Comparing the middle and high dose groups of p-DCB mothball with the negative control, the micronucleus frequency was significant differences (P<0.05). CONCLUSION: The market public Para-dichlorobenzene mothball.had genotoxicity to plant cells.

BACKGROUND ＆ AIM： Aim To Compare the difference between using whole blood specimen and abstracted lymphocyte in comet assay in order to simplify the process of comet assay. MATERIAL AND METHODS：The whole blood specimen and abstracted lymphocyte of mice after injecting K2Cr2O7 and ethanol were used in comet assay to compare the degree of DNA damage. RESULTS： There was no difference of DNA damage of whole blood specimen and abstracted lymphocyte induced by those two noxious substances. CONCLUSION： Whole blood specimen is more convenient than abstracting lymphocytes in comet assay for detecting and screening of medicine on a large scale.