Objective:To investigate whether superantigen SEB,with the assistance of APCs,could induce apoptosis of thymocytes in vitro,and to study the mechanism involved.Methods:SEB was given to thymocytes which were cultured together with APCs.Apoptosis was detected by DNA electrophoresis and DNA fragmentation assay.Expressions of Fas and FasL were detected by flow cytometry.Results:The thymocytes treated with SEB had the characters of apoptosis,and the apoptotic rate and expressions of Fas and FasL was significantly increased compared with control.Conclusion:SEB,together with APCs,can induce apoptosis of thymocytes in vitro,high expressions of Fas and FasL on thymocyte may participate in the mediation of apoptosis.This may provide a method to study the negative selection of thymocytes.

AIM:To estimate the toxicological characterization of Jiutong Capsule(Radix Puerariae lobatae,Fructus seu Semen Hoveniae,etc.).METHODS:The acute toxicity test,micronucleus test of bone marrow cell,sperm shape abnormality test in mice,the Ames test,and 30 days feeding test in rat were performed.RESULTS:(1) The acute toxicity test showed that LD_ 50 of Jiutong Capsule was more than 10.0 g/kg.(2) The result of Ames test,micronucleus test of bone marrow cell,and sperm shape abnormality test were negative.(3) The 30 days feeding test showed that Jiutong Capsule had no cumulate toxicity in mice.CONCLUSION:The results show that Jiutong Capsule does not have toxicity,and it can't cause mutation and heredity toxicity.

Objective To investigate the effect of microRN-206 (miR-206) on the expression of Cyclin-dependent kinase 4 (CDK4) and Cyclin G-associated protein kinase (GAK), and the growth of prostate cancer cells.Methods Prostate cancer cell lines DU-145 and PC-3 were transfected with miR-NC (the control group) or miR-206 (the experimental group).The expressions of CDK4 and GAK mRNA were detected by real-time quantitative PCR (qRT-PCR).The expressions of CDK4 and GAK protein were detected by Western blotting.Cell cycle distribution was detected by flow cytometry.EdU proliferation assay and colony forming assay were used to analyze the cell proliferation ability.Results In DU-145 and PC-3 cells, the expressions of CDK4 mRNA in miR-NC group were 1.00±0.09, 1.00±0.10, the expressions of GAK mRNA were 1.00±0.05, 1.00±0.06.The expressions of CDK4 mRNA in miR-206 group were significantly decreased in DU-145 (0.36±0.18;t=6.572, P=0.001) and PC-3 cell lines (0.43±0.17;t=5.794, P=0.001).The expressions of GAK mRNA were also significantly decreased in DU-145 (0.23±0.04;t=22.420, P<0.001) and PC-3 cell lines (0.32±0.08;t=14.500, P<0.001).Western blotting results were consistent with qRT-PCR results.The results of flow cytometry showed that compared with the miR-NC group of DU-145 and PC-3 cell lines, the percentage of cells in S phase (23.60%±5.68% vs.32.53%±4.52%, t=2.462, P=0.049;22.09%±4.35% vs.30.96%±4.86%, t=2.720, P=0.035) and G2-M phase (16.28%±7.12% vs.26.63%±4.33%, t=2.484, P=0.048;14.60%±1.62% vs.24.68%±7.13%, t=2.758, P=0.033) decreased after transfection of miR-206, and the percentage of cells in G0-G1 phase (60.13%±5.82% vs.40.84%±5.37%, t=4.872, P=0.003;63.31%±3.27% vs.44.36%±3.82%, t=7.533, P<0.001) increased.The results of EdU proliferation assay showed that the proliferation abilities were significantly attenuated after transfection of miR-206 (22.56±3.81 vs.38.90±8.51, t=3.503, P=0.013;25.12±6.42 vs.48.45±8.92, t=4.244, P=0.005).The results of colony formation experiments showed that the numbers of colonies formed by DU-145 and PC-3 in miR-NC group were 218.66±44.59 and 177.35±24.49, respectively.The numbers of colonies formed in miR-206 group were 125.38±32.80 (t=3.370, P=0.015) and 82.65±14.05 (t=6.708, P=0.001), suggesting that cell proliferation ability in miR-206 group was reduced.Conclusion miR-206 significantly inhibits the growth of prostate cancer cells by interfering with the expressions of CDK4 and GAK, suggesting that miR-206 may be a molecular targeted therapy tool for prostate cancer.

Objective To investigate the effect of dsP21-555 transfection on the expression of tumor suppressor gene p21 in renal clear cell carcinoma cell lines ACHN and 786-O.Methods Renal clear cell carcinoma cells were transfected with dsControl and dsP21-555 with Lipofectamine 3000 respectively.Real-time quantitative PCR (RT-qPCR) and Western blotting were used to detect the expression of p21 mRNA and protein.Cell cycle distribution was detected by flow cytometry (FCM).Cell viability and proliferation were analyzed by cell viability assay (MTS method) and colony culture assay.Results In ACHN and 786-O cells, the expressions of p21 mRNA in dsP21-555 group (2.86±0.33, 1.96±0.35) were significantly higher than those in dsControl group (1.05±0.34, 1.01±0.14), which were increased to 2.72 times (t=7.640, P<0.001) and 1.95 times (t=5.058, P=0.002).Western blotting showed that the expressions of P21 protein were up-regulated in both renal cell lines, which was consistent with p21 mRNA up-regulation.The result of FCM showed that the cell cycle was blocked in G0-G1 phase (57.08%±5.66% vs.46.06%±4.60%, t=3.023, P=0.023;61.58%±6.23% vs.42.25%±6.08%, t=4.444, P=0.004) after transfection of dsP21-555 in renal clear cell carcinoma cells.MTS result showed that the vitality of both cell lines after transfection of dsP21-555 decreased compared with dsControl group, their absorbance values were 0.85±0.20 vs.1.27±0.13, t=3.410, P=0.014;1.04±0.25 vs.1.55±0.10, t=3.758, P=0.009.Colony culture experiments showed that the numbers of colonies formed by ACHN and 786-O in the dsControl group were 110.91±26.21 and 129.99±22.87 respectively, and the numbers of colonies formed in the dsP21-555 group were 59.37±14.23 (t=3.456, P=0.014) and 71.26±21.38 (t=3.745, P=0.010), indicating that the proliferation of cells in the dsP21-555 group was significantly reduced.Conclusion dsP21-555 can up-regulate the expression of p21 gene in renal clear cell carcinoma cells and inhibit the growth of carcinoma cells, suggesting that dsP21-555 may become a new gene therapy tool.

Aim To study the relationship between the expressions of Fas,Fas-L and the spontaneous apoptosis of thymocytes in vitro. Methods The expressions of Fas,Fas-L and the apoptotic rate of thymocytes were assayed by flow cytometry. Results The apoptosis and the Fas expression of thymocytes of different culture times in vitro were increased time-dependently in vitro. The Fas-L expression of thymocytes cultured for 24 h was also significant increase. There was significant corelation between the increase of Fas expression and the increase of apoptosis of thymocytes in vitro. Conclusion Fas is an important molecule which mediates spontaneous apoptosis of thymocytes cultured in vitro.

Objective To investigate the combined biological effects of low dose radiation,carbon monoxide,benzene and noise on rats.Methods Sixteen male SD rats were randomly divided into experiment group and control group.The experiment group was exposed to carbon monoxide,benzene,low dose radiation and noise daily,the control group was in common environment.Peripheral blood,organ index,and marrow DNA content were detected.Two-dimensional electrophoresis (2-DE) was performed on serum protein analysis.Differential expressed proteins were identified by a matrix assisted laser desorption/ionization time of flight mass spectrometry (MAIDI-TOF-MS).Results Compared to control group,the liver index,spleen index,thymus index,leukocytes,platelets count,and marrow DNA content of the experiment group were decreased significantly (t =2.732,4.141,3.053,2.211,2.668,11.592,P ＜0.05).12 altered proteins were detected and through identification,3 proteins were definite in terms of serum amyloid A-4 protein (SAA4),trichoplein keratin filament-binding protein (TCHP) and tubulin alpha-4A chain (TUBA4A).Conclusions The hematopoietic system and immune system of rats are damaged significantly with the changes of several serum protein expressions by the combined exposure of low dose radiation,carbon monoxide,benzene and noise.This study may provide new information for the mechanism of the combination effects.

Objective To evaluate the protective effects of Sipunculus nudus preparation(SNP) on mice irradiated by 60Co.Methods The mice were divided into control group,model group and 0.5,1.0,and 2.0g?kg-1?d-1 SNP groups.SNP was administrated by intra-gastric infusion with the volume of 0.4mL per 20g.In the fifteenth day,the model group and the treated groups were irradiated by ?-ray of 60Co(0.83Gy/h) with the dose of 5 Gy.Peripheral blood WBC,RBC,PLT,the spleen(SI) and thymus index(TI),the BMNC,SOD and MDA in serum,testicle index,germ cells were detected.Results Comparing with the model group,TI,SI and peripheral blood WBC,RBC and BMNCs were higher.The activities of SOD in serum were increased,while MDA decreased.Testicle index and germ cells were increased,and germ abnomality rate was decreased in SNP groups.Conclusion SNP has protective effects on mice irradiatied by 60Co.

Objects To study the protective effects of cimetidine against oxidative stress in rats induced by cumulative low-dose irradiation.Methods Sixty SD rats were randomly divided into 6 groups (10 each):normal control group,model control group,lentinan group [89mg/(kg.d)] and 3 dose groups of cimetidine.After oral administration,all the rats were exposed to γ-ray irradiation 8 hours/day for 12 days,and sacrificed on the 13th day.The activities of superoxide dismutase (SOD),glutathione peroxidase (GPx),catalase (CAT) and the content of malondialdehyde (MDA) in serum,liver,thymus and spleen were determined.By using the superoxide anion radical system,hydroxyl radical system,H2O2 radical system,oxidation system of linoleic acid induced by alkane radical system and diphenyl picryl hydrazinyl radical (DPPH) radical system,the antioxidation activities of cimetidine were detected.Results The activities of SOD in liver and thymus decreased significantly,the GPx activity in serum,liver and spleen decreased significantly and MDA level in serum,liver and spleen increased significantly after 0.3Gy cumulative ionizing radiation.Cimetidine enhanced the activities of antioxidant enzymes in serum and organs,and reduced the MDA level.In a certain concentration range,cimetidine had different scavenging effects onto these radical systems,and showed good performance in hydroxyl radical.Conclusion Cimetidine can effectively ameliorate the oxidative stress from low-dose cumulative irradiation by scavenging free radicals,increase the activity of antioxidant enzymes and reduce the content of lipid peroxidation products,thus presents a potential radio protective effect.

Objective:To prepare old tea buccal tablets using wet granulation method and optimize the preparation technology. Methods:The amount of each adjuvant was studied by single factor experiments, and the formula of the buccal tablets was optimized by the orthogonal experiments using taste and disintegration time as indices. Results:The optimal formula was composed of old tea ex-tract 30 g,mannitol 60g,PEG6000 20 g,aspartame 10 g,citric acid 10 g and menthol crystal 1 g. All the tested indices including ap-pearance, hardness and disintegration time met the requirements described in Chinese pharmacopeia. Conclusion: The preparation technology is reasonable and feasible for the industrial production.

Objective:To establish the quality standard for Sipunculus nudus polysaccharide. Methods:The water content, igni-tion residues and heavy metals in Sipunculus nudus polysaccharide were determined. Authrone-sulfuric acid colorimetry was used to de-termine the polysaccharide content. Results: The water content in the polysaccharide should not exceed 5. 0%, ignition residues should not exceed 1. 0%, and the content of heavy metals should not exceed 20 ppm. The polysaccharide content should exceed 80%( glucose) . Conclusion:The method is accurate and simple, and can be effectively used in the quality control of polysaccharide in Sipunculus nudus Linnaeu.