Objective To review the treatment effect of limited disease small cell lung cancer (LD-SCLC) and to evaluate the prognosis factors for SCLC. Methods From Aug. 2002 to Feb. 2006, 212 patients of SCLC confirmed with pathology and cytology were. Treated by combined modality. All patients were treated with chemotherapy 2-6 cycles, 59 patients of which were treated with only chemotherapy, 108 patients of which were treated with chemotherapy plus radiotherapy, 45 patients of which were treated with surgery plus chemotherapy with or without radiotherapy. The patients of radiotherapy were exposed to 6 or 10 MV X-ray with a total dose of 40-66 Gy in 4-7 weeks. Results The overall median survival time was 15 months. The 1-,2- and 3-year overall survival rate were 58.0%, 33.2% and 22.1%, respectively. Univariate analysis indicated that weight loss, age, LDH, ECOG performance status, operation, response to radio-chemotherapy, cycles for chemotherapy, radiotherapy irflueoced survival significantly in LD-SCLC. Multivariate analysis suggested that ECOG performance status, response to therapy, cycles for chemotherapy were the independent prognostic factors for LD-SCLC. Conclusions For LD-SCLC patients, ECOG performance ≤ 1, good response to radio-chemotherapy, and ≥ 4 cycles chemotherapy show encouraging survival rate, Distance metastasis is still the mainstay of treatment failure.

Objective To investigate the change of ATM phosphorylation in HepG2 cells following a condnuous low dose-rate irradiation.Methods Cells were pemistendy exposed to low dose-rate(8.28 cGy/h) irradiation.Indirect immunofluorescence and Western blot were used to detect the expression of ATM phosphorylated proteins.Colony forming assay Was used to observe the effect of a low dose-rate irradiation on HepG2 cell survival.Results After 30 min of low dose-rate irradiation.the phosphorylation of ATM occurred.After 6 h persistent irradiation,the expression of ATM phosphorylated protein reached the peak value,then gradually decreased.After ATM phosphorylation was inhibited with Wortmannin,the surviving fraction of HepG2 cells was lower than that of the irradiation alone group at each time point(P<0.05).Conclusions Continuous low dose-rate irradiation attenuated ATM phosphorylation.suggesting that continuous low dose-rate irradiation has a potential effect for increasing the radiosensitivity of HepG2 cells.

Objective To evaluate the radioprotective effects of Quercetin (QN) on 6 Gy X-ray irradiation-induced immune dysfunction and toxicity in hepatic tissue in rats. Methods 40 adult rats were randomly divided into 4 groups. Group Ⅰ was injected intraperitoneally with saline solution for 7 consecutive day sand served as control group. Group Ⅱ was daily injected with QN (40 mg/kg) for 7 consecutive days. Group Ⅲ was irradiated with a single dose of 6 Gy X-ray. Group Ⅳ received a daily injection of QN (40 mg/kg) for 7 consecutive days, and 1 h after the last injection rats were irradiated with a single dose (6 Gy) X-ray irradiation.The animals were sacrificed after 24 h. Lymphocyte transforming rate was measured with MTT method, and CD+4 T, CD+4 T and CD+8/CD+8 T were measured with flow cytometry method. Oxidative conditions in liver were measured with malondialdehyde (MDA), reduced glutathione hormone (GSH), supernxide dismutase (SOD) andglutathione peroxidase (GSH-Px) activities kits. HE staining was used to observe the general condition of rat's liver. Results Lymphocyte transforming rate, CD+4 T, CD+8 T and CD+8/CD+8 T in rats of Group Ⅳ were all higher than those in rats of Group Ⅲ ( F = 8.455,22.644, 18.911, P < 0.01 ). MDA content in the Group Ⅳ rat's liver was lower than that in the Group Ⅲ ( F = 10.059, P < 0.01 ) and antioxidant enzymes SOD, GSH-Px activities were higher than those in Group Ⅲ (F = 23.688,186.046,19.788, P < 0.01 ). The capillary of the hepatic lobules dilated and congested obviously in portal area, involving infiltration of polymorphonuclear leukocytes in the Group Ⅲ, while QN improved this change apparendy. Conclusions Pretreatment with Quercetin improved the irradiated rat's immune functions and protected the irradiated rats from oxidative stress to some extent.

Objective To investigate the radiosensitizing effects of cyclooxygenase-2 selective inhibitor LM-1685 on A549 cells in vitro.Methods A549 human lung adenocarcinoma cell line was used in this study.Cell growth kinetics Was determined using MTT assay.Cell survival was analyzed by clonogenic assay.The change of cell cycle Was measured by flow cytometry.Results LM-1685 inhibited the growth of A549 cells,showing a dose-dependent and time-dependent manner.LM-1685(50/μmol/L),either with or without IL-1β,showed the radiosensitizing effects on A549 cells,and the sensitizing enhancement ratio(SER)was 1.12 and 1.06,respectively.LM-1685(50 μmol/L)abrogated radiation-induced G2/M arrest of the tested A549 cells.Conclusions Cyclooxygenase-2 selective inhibitor can enhance the radiosensitivity of A549 cell line.Abrogation of radiation-induced G2/M arrest could be part of the mechanism.

Objective To develop measurement of reference air kerma for192Ir sources with NE 2570 electrometer,2571 ion-chamber and machining measured holder.Methods The measuring holder was placed at the distance of 1 m from the walls,the floor and ceiling,the ion-chambet was insert into the oolymethyl methacrylate(PMMA)jig of the measuring holder,lhe optimum distance is 16 cm from the source centre to ionchamber centre.The source was transmitted by the afterloding system to the plastic pipe to measure reference air kerma of the source.According to calibration factors from60Coγrays and 250 kV X rays with air exposure to calculated the air kerma calibration factor,the air kerma calibration factor of 192Ir soHree was calculated bv60Co γ rays and the effective energy of the 250 kV X ray beam.The scatter correction factor was giverl by the shadow shield experiment for the wails,the floor,the air and the measuring holder,the correction factors were given for the attenuation of primary photons in air and the electrons entering the air cavity are mainly generated in the innerwall of the chamber by 1079 report in IAEA.Results Two measuring methods were used for192Ir source undersame environment condition,the ion-chatuber and well-type chamber values are 1.584×1011Bq and 1.561×1011Bq respectively,and the relative deviation from them is within 1.4%,Conclusions The air kerma measurement of 192Ir source the ion-chamber with is not depended on the source geometry(point seurce,line source etc),the size.and the material of shell,the shape,the quality of materials and the size of the chamber.The uncertainty error of the air kerma is lessin comparison to the air exposure.

Objective To explore whether antisense-EGFR could enhance the radiosonsitivity of human lung cancer spc-a-1 cell line.Methods The spc-a-1 cells were transfected with antisenso.EGFR-pcDNA3 by lipofectamine 2000(pcDNA3 antiEGFR group).Two other groups were used for comparison:control group(spc-a-1 cell without transfection)and pcDNA3 group(spc-a-1 cell transfeeted with pcDNA3 which did not contain antisense EGFR).Cell clones that stable expressing antisense-EGFR wa8 selected with G41 8 and the suppression of the expression of EGFR mRNA and protein were detected by RT-PCR and Western blot.The influence of antisense-EGFR on cell cycle was testified by flow cytometry assay.The cell apoptosis was analyzed by flow cytometry after 8 Gy irradiation.Further,cells of each group were irradiated with X-rays at the dose of 0,2,4,6 and 8 Gy.Dose-survival curve of each group was established by colony-forming assay.Results The expression of EGFR mRNA and protein were significantly inhibited after antisense-EGFR-pcDNA3 transfection.The cells arrested at the G2/M phase in the pcDNA3 antiEGFR group,control group and pcDNA3 group were (29.53±1.91)%,(13.7±1.30)%and(12.40±1.34)%,respectively.The apoptosis index of spc-a-1 cells in the antisonse-EGFR combined with irradiation group was obviously higher than that of the comparable groups [(39.24±1.57)%,(13.79±0.63)%and(15.02±0.85%)].The values of D0,Dq,SF2 of pcDNA3 antiEGFR group declined obviously compared with the control group(2.11,2.49,0.84 vs 1.19,0.15,0.32).Conclusions Antisense-EGFR could induce the G2/M cell cycle arrest,promote cell apoptosis and inhibit the ability of sublethal cell damage repair induced by irradiation,80 that it could significantly improve the radiosensitivity of spc-a-1 cell in vitro.

Objective To carry out the quality control testing and evaluation for three digital mammography systems.Methods The performance of three digital mammography systems was assessed by applying methods recommended in the European guidelines for quality assurance in breast cancer screening and diagnosis and Chinese specification for testing of quality control in X-ray mammography.The performance of X-ray generator of three digital mammography systems were tested and evaluated.CDMAM 3.4 phantom with four different thickness(30,40,50,60 mm) were exposured in DR,PCM,and CR system,respectively.The average glandular dose (AGD) value was measured and image quality figure (IQF) analysis was performed in each thickness.Results The X-ray machine performance of DR and CR was in accordance with existing standard,however the standard was inappropriate to evaluate part of X-ray machine performance of PCM system.The AGDs for system DR were 1.20,1.42,1.75 and 2.20 mGy for 30,40,50 and 60 mm PMMA thickness,respectively.The respective AGDs for system PCM and CR were 0.82,1.19,1.33,1.70 mGy and 0.59,0.88,1.47,2.19 mGy.For the same phantom thickness sequence,the IQFs were 21.36,21.57,27.25 and 30.58 for system DR,28.02,29.10,35.90,and 41.24 for system PCM,whereas they were 39.78,39.30,43.85 and 48.08 for system CR.Conclusions The AGDs of all three systems were in accordance with the values recommended in European guideline.The AGD and IQF could provide an effective way for performance assessment and constancy checks for digital mammography systems.

Objective To compare the planning systems of the simplified manual intensity modulated (SMIM) irradiation and standard tangential (ST) irradiation,in order to explore the application of SMIM technique in clinic.Methods In 64 cases of breast cancers after breast conserving surgery,each underwent both SMIM and ST planning systems.SMIM planning was designed by copying additional fields for shielding the high dose areas from internal or lateral tangential field.The high dose areas were reduced by adjusting the size of the additional field and open tangential field.To optimize the SMIM planning,3 high dose areas (＞ 103% ,＞ 105% and ＞ 107%) were shielded and 3 protocols carried out.The wedges were also optimized in ST plan.The target coverage and dose homogeneity and dose of organ at risk were compared between SMIM and ST planning systems.Results When the dose was normalized to cover the volume of 95% CTV,85% of the shielded areas in optimal SMIM planning were that of ＞ 103% high dose area,and 94% of target area was covered.The study on the volume of breast CTV showed that,in the large breast group,SMIM could not only significantly reduce the high dose areas,and the maximum dose as well as the dose of organ at risk,but also enhance the dose homogeneity index.However,no such effect was not significant in the small breast group.Conclusions The simplified manual intensity modulated technique can improve target dose homogeneity in the large breast cases instead of the standard tangential technique.

Objective To introduce a finger leaf design that is applied to dual layer MLCs.Methods An optimization model was firstly constructed to describe the problem of determining leaf end shapes,and the corresponding problems were then solved by the simplex search method or the simulated annealing technique.Optimal parameters for arc shapes of leaf end projections were obtained,and a comparison was done between optimized MLCs and conventional MLCs in terms of field conformity.The optimization process was based on 634 target fields selected from the patient data base of a treatment planning system.Areas of these fields ranged from 20.0 to 602.7 cm with a mean and its standard deviation of (125.7 ±0.0) cm~2.Results The optimized leaf end shapes projected to the isocenter plane were semicircles.With the finger leaf design,the total area of discrepancy regions between MLC fields and target fields was reduced by 32.3% .Conclusions The finger leaf design improves the conformity of the MLC shaped fields to the desired target fields.

Purpose To develop a national registry and reporting system of individual monitoring for workers occupationally exposed to ionizing radiation.Methods In accordance with the relevant law,regulations,standards and the current health supervision practice for radiation workers in China,to ensure more effective collection of information on individual monitoring from all levels of service providers across the country and an easy query and analysis of the collected information for both service providers and administrative institutions,the register consisted of an offline-system and a web-based information system.The off-line system consisted of 8 tables,which could easily make annual and period monitoring reports,and upload individual monitoring data in compressed and encrypted format.Web-based system consisted of 6 modules,could easily make S customized tabulations of monitoring data and show 2 trend figures.SSLVPN secure remote access was used in the system.Arranged by the Ministry of Health,training courses provided to all individual monitoring service providers and provincial administrative institutions.Results A new and individual-based national register and reporting system of individual monitoring for workers occupationally exposed to ionizing radiation was successfully developed,and would be officially run soon.Conclusions The establishment and running of the register would be great improvement on the national radiological health reports and produce a far-reaching impact on the individual monitoring in China.