Objective To ascertain the concentrations of uranium in drinking water around nuclear power plants.Methods A total of 106 water samples were collected from June 2009 to March 2010 in Jiangsu,Zhejiang,Liaoning and Shandong provinces.Inductively coupled plasma-msgs spectrometry(ICPMS)was applied to determine uranium content in local water source and drinking water.The detection limit of U was 0.8 ng/L.The recovery was 100.9%.Results The uranium concentrations in all samples were less than 15μg/L which was the limit given by World Health Organization(WHO).Conclusions The concentration of uranium in water sources was as follows:Liaoning>Shandong>Jiangsu>Zhejiang.The concentration of uranium in drinking water W88 maximal in Shandong Province and minimal in Zhejiang Province.

Objective To explore the effeetiviness of the method of LabSOCS(Laboratory sourceless calibration software)efficiency calibration in laboratory rapid analysis for emergency monitoring of nuclear incidents.Methods The detection efficiency of three kinds of environmental samples in emergency monitoring Wag calculated bY using the LabSOCS efficiency calibration method,and compared with the values that were obtained by way of radioactive source calibration method.Results The maximum relative deviation of the detection efficiency between the two methods was less than 15%,and the values with relative deviation less than 5%accounted for 70%.Conclusions The LabSOCS efficiency calibration method might take the place of radioactive source efficiency calibration method,and meet the requirement of rapid analysis in emergency monitoring of the nuclear incidents.

Objective To study the difference of gene expression profile between the radioresistant human nasopharyngeal carcinoma cell line CNE-2R and CNE-2,and to screen the signaling pathway associated with radioresistance of nasopharyngeal carcinoma.Methods The radioresistant nasopharyngeal carcinoma cell line CNE-2R was constructed from the original cell line CNE-2.CNE-2R and CNE-2 cells were cultured and administered with 60Co γ-ray irradiation at the dose of 400 cGy for 15 times.Human-6v 3.0 whole genome expression profile was used to screen the differentially expressed genes.Bioinformatic analysis was used to identify the pathways related to radioresistance.Results The number of the differentially expressed genes that were found in these 2 experiments was 374.The Kegg pathway and Biocarta pathway analysis of the differentially expressed genes showed the biological importance of Toll-like receptor signaling pathway and IL-1 R-mediated signal transduction pathway to the radioresistance of the CNE-2R cells and the significant differences of 13 genes in these 2 pathways,including JUN,MYD88,CCL5,CXCL10,STAT1,LY96,FOS,CCL3,IL-6,IL-8,IL-1α,IL-1B,and IRAK2(t=13.47-66.57,P<0.05).Conclusions Toll-like receptor signaling pathway and IL-1R-mediated signal transduction pathway might be related to the occurrence of radioresistance.

Objcetive To investigate the protective effects of the nitroxides R-1 on human liver cells exposed to ionizing radiation.Methods Human liver cells L-02 were cultured and irradiated with 60Co γ-rays at the doses of 0,1,2,4,and 8 Gy,in order to screen the proper irradiation dose.WR2721 at the terminal concentration of 4 mmol/L was used as positive control.L-02 cells irradiated with 4 Gy were added with R-1 at the terminal concentration of 0.25 μmol/L at 30 min before irradiation or immediately after irradiation.MIT method was used to screen the proper conditions for follow-up experiment 72 h later.L-02 cell culture fluid was added with R-1 at the concentrations of 0,0.125,0.25,0.5,and 1 μmol/L,respectively for 30 min before irradiation at the doses of 0,1,2,4,and 8 Gy to ealculate clone formation rate at 10 d post-irradiation.L-02 cells were cultured and divided into 4 groups:control group without any treatment.drug group pretreated by 0.25 μmol/L R-1 only,irradiation group,irradiated at 4 Gy only,and drug + irradiation group with combination of 0.25 μmol/L R-01 and 4 Gy irradiation.The inverted microscopy and Hoechst 33258 staining and flow eytometry were used to observe the apoptosis of the cells at 24,48,and 72 h later.Results Nitroxides R-1 did not inhibit the viability of L-02 cell when its concentration was less than 1 μmol/L and it inhibited the L-02 cell growth when the concentration wu higher than 2 μmoL/L.The A value and colony formation rate of different concentration of R-1 groups were all higher than those of the irradiation group,and the effect of the 0.25 μmol/L drug concentration group was the most significant.Consequently,the concentration 0.25 μmoL/L was selected for follow-up experiment.Compared with the irradiation group,the L-02 cells of the pretreatment group showed solid adherence, increased refraction,clear outline,less apoptotic and dead cells at 4 Gy post-irradiation.Conclusions Nitroxides R-1 can protect the human liver cells from 60Coγ-ray induced injury effectively.The mechanism of its protective effect may be the reduction of apoptosis.

Objective To study the dose-and time-effects of X-ray irradiation on the expression of Pokemon gene in A549 cells of human lung adenocarcinoma.Methods A549 cells were cultured in vitro and exposed to X-rays with the doses of 2,4,6 and 8 Gy,respectively.Untreated A549 cells were used as control group.The relative levels of Pokemon mRNA expression in the cells were detected by using quantitative real-time PCR at 2,4,8,12,24,48 and 72 h after irradiation.Results The Pokemon mRNA expression levels decreased in the early period after irradiation(except 2 and 4 h after irradiation in 2 Gy group)and then increased in the later stage(48 h after irradiation)with significant statistical differences at the most time points in comparison with the control group(t=3.40-154.76,P<0.05).Conclusions Higher doses of X-rays may degrade the expression of Pokemon mRNA in the human A549 cells and induce apoptosis in the early period,hut also may upgrade its expression in the later period, which might be correlated with the cell cycle regulation and DNA damage repair in the A549 cells.

Objective To explore the effects of X-ray irradiation combined with RNAi against signal transducer and activator of transcription 3(STAT3)on the radiosensitivity of human esophageal carcinoma cells.Methods Human esophageal carcinoma cells of the line Eca-109 were euhured.Three pairs of DNA template aiming at the base sequences of the coding regions 2037-2055,1243-1261,and 455-473 of the STAT3 mRNA were synthesized(siRNAI,siRNA2,and siRNA3),and a negative sequence was synthesized to be used as control.STAT3-siRNA positive recombinant plasmids(pRNAT-U6.1-siRNAI,pRNAT-U6.1-siRNA2, and pRNAT-U6.1-siRNA3), and a STAT3-siRNA negative recombinant plasmid (pRNAT-U6.1-negative)were thus constructed and then transfected into the cultured Eca-109 cells,which were divided into transfection reagent control group,pRNAT-U6.1-siRNAl-3 transfection groups,and pRNAT-U6.1-negative centrel group.The positive eell clones were screened.RT-PCR and Westem blotting were used to detect the STAT3 mRNA and protein expression.The transfected Eca-109 cells were exposed to 0,2,4,6,and 8 Gy of X-rays,respectively,and the survival fraction of the cells was analyzed by clone formation assay.Flow cytometry was applied to analyze the cycle arrest and cell apoptosis 4 Gy post-irradiation.Results Agarose gel electrophoresis confirmed the successful construction of the plasmid pRNAT-U6.1-siRNA.RT-PCR and Western blotting demonstrated that the mRNA and protein expression levels of STAT3 transfected with sTAT3-siRNA3 were both significanfly lower than those of the control groups.At 2-8 Gy, the survival fractions of the siRNA3 group were aU significantly lowered than those of the control group(t＝-0.228--0.051,P<0.05).Flow cytometry showed that the percentage of the cell cycle G0/G1 phase and the apoptosis rate of the siRNA3 group were both significantly higher than those of the control groups at 4 Gy post-irradiation(t＝-13.137-16.350,P<0.01).Conclusions X-ray irradiation combined with RNAi against sTAT3 could inhibit the proliferation of the human esophageal carcinoma cells,induce cell cycle arrest and apoptosis,improve the radiosensitivity in Eta-109 cells.

Objective To investigate the value of cytokinesis-block micronuclei(CBMN)assay in estimation of the biological doses of the victims of radiation accident.Methods Samples of peripheral blood were collected from the 5 victims(Subjects 1-5)at 16 h after the radiation accident of Taiyuan,Shanxi Province.And the peripheral blood samples and bone marrow sample were collected from the victim No.1 at 23 and 24 h after the radiation.Eight days after the accident Subject 1 underwent allogeneic peripheral blood hematopoietic stem cell transplantation.At difierent time points in the period of 1 year after the accident.peripheral blood samples were collected from these 5 victims.CBMN assay was conducted on the peripheral blood lymphocytes on the samples,and the biological doses were estimated based on the micronuclei(MN)frequencies.The nuclear division index(NDI)obtained from in vitro irradiation experiment using high dose of 60Coγ-rays was used to estimate the exposed doses for Subject 1. Dynamic arialysis of the MN frequency for the 5 victims was performed in the period of 1 year after the accident.Results The MN frequency of Subject 1 surpassed the value corresponding to the upper limit of the MN dose.effective curve.The dose range estimated bv the combination of the CBMN and NDI (CBMN+NDl)assay was 10-20 Gy for Subject 1.The doses estimated by MN frequency for Subjects 2,3,4,and 5 were 3.6,2.9,2.3,and 2.9 Gy,respectively.The estimated doses were in accordance with those estimated by physicat method.chromosome aberration analysis.and clinical symptoms.Prominent decrease of the MN frequency was observed at 26 d after the accident(18 d after the transplantation)for Subject 1(u=3.295,P<0.05).Gradual decrease of MN frequency was observed after the accident for Subjects 2,3,4,and 5.The MN frequencies 1 month after the accident of Subjects 3,4,and 5 were all significantly lower than those 16 h later(u=6.874,4.526,and 7.811,P<0.05).Conclusions Quick and accurate.CBMN assay reinforces and verifies the result of chromosome aberration analysis.The new index CBMN+NDI assay is of reference valne for estimating higher dose of irradiation.

Objective To explore the effects of andrographolide(AP),extracted from the traditional Chinese herb Andrographlis paniculata(AP),on injury induced by radiation exposure.Methods Sixty male rats were randomly divided into 4 equal groups and irradiated with 60Co γ-rays at the doses of 1,2,and 4 Gy,respectively:low dose AP group(intragnstrically administered with AP at the dose of 100 ms/kg daily for 10 d before irradiation),and high dose AP group(intragastrically administered with AP at the dose of 200 ms/kg daily for 10 d before irradiation),model group(administered with the same volume of normal saline instead of AP for 10 d before irradiation),and control group(irradiated only at 3 different doses).One day after irradiation all rats were killed with their livers being fixed to make paraffin section.The morphological feature was observed under light microscope after HE staining,and the cell apoptosis was detected by TUNEL technology.Results Compared to the control and model groups,the pathological changes of liver were significantly gentler in the AP treatment groups.The apoptosis rates of the liver cells of all the AP sub-groups were significantly lower than those of the control and model subgroup(t=2.19-4.80.P<0.05).Conclusions AP might have prevention effect against radiation exposure.

Objecttve To compare the positional and volumetric differences of planning target volumes(PTVs)based on axial three-dimensional CT(3D-CT)and four-dimensional CT(4D-CT)for the primary tumor of non-small cell lung cancer(NSCLC).Methods Sixteen NSCLC patients with lesions located in the upper lobe and 12 patients with lesions in middle and lower lobes,totally 28 patients, initially underwent three-dimensional CT scans followed by 4D-CT scans of the thorax under normal free breathing.PTVvector was defined on gross tumor volume (GTV) contoured on 3D-CT and its motion vector. The clinical target volumes(CTVs)were created by adding 7 mm to GTVs,then, internal target volume (ITVs)were produced by enlarging CTVs isotropically based on the individually measured amount of motion in the 4D-CT,lastly,PTVs were created by adding 3 mm setup margin to ITVs. PTV4D was defined on the fusion of CTVs on all phases of the 4D data.The CTV wag generated by adding7 mm to the GTV on each phase.then,PIVs were produced by fusing CTVs on 10 phases and adding 3 mm setup margin.The position of the target center,the volume of target and the degree of inclusion(DI)were compared reciprocally between the PTVvector and the PTV 4D The difference of the position,volume and degree of inclusion of the targets between PTVvecter and PTV4D were compared,and the relevance between the relative characters of the targets and the three-dimensional vector was analyzed based on the groups of the patients. Results The median of the 3 D motion vector for the lesions in the upper lobe was 2.8 mm, significantly lower than that for the lesions in the middle and lower lobe ( 7.0 mm, z = - 3. 485, P < 0. 05 ). In the upper lobe group there was only significant spatial difference between the PTVvector and PTV4D targets in the center coordinate at the x axe (z = -2. 010, P < 0. 05 ), while in the middle and lower lobes there was only significant spatial difference between the PTVvector and PTV4D targets in the center coordinates at the z axe (z = -2. 136,P <0.05). The median of ratio of PTV4D and PTVvector, of the upper lobe group was 0. 75, significantly higher than that of the middle and lower lobes group (0. 52, z = - 2. 949, P < 0. 05 ).A significant correlation was found for the motion vector and the ratio of PTV and PTV4D in both groups ( r = - 0. 638, - 0. 850, P < 0. 05 ). For all patients, the median of D[ of PTV4D in PTVvector was 66. 39% ,while the median of DI of PTVvector, in PTV4D was 99. 55% , both showed a positive significant correlation with the motion vector (r = -0. 814,0. 613 ,P < 0. 05). Conclusions PTV4D defined based on 4D-CT simulation images is obviously less than PTV defined based on 3D-CT simulation images. The ratio and DI of both targets are related with the three-dimensional motion vector of the tumor.

Objective To develop a new software system that cau directly display the predicted results on an electronic map,in order to get a directly perceived understanding of the affected areas of nuclear and radiological terrorism events in city areas.Methods Three scenarios of events including spreading radioactive materials, dirty bomb attack,and explosion or arson attacks on the radiation facilities were assumed.Gaussian diffusion model was employed to predict the spread and deposition of radioactive pollutants,and both the internal and external doses were estimated for the representative person by using the corresponding dose conversion factors.Through integration of the computing system and Mapinfo geographic information system(GIS),the predicted results were visually displayed on the electronic maps of a city.Results The new software system could visually display the predicted results on the electronic map of a city, and the predicted results were consistent with those calculated by the similar software Hotspot(R)The deviation between this system and Hotspot was less than 0.2 km for predicted isoplethic curves of dose rate downwind.Conclusions The newly developed software system is of the practical value in predicting the effects of nuclear and radiological terrorism events in city areas.