Objective To investigate the effects of the polluted organic substances in urban water environment and genetoxicity of the organic pollutants in drinking water on DNA damage in primary cultured hepatocytes in rats. Methods Qualitative analysis of the organic extracts from source water and drinking water in five waterworks in city C with GC/MS was conducted and the effects of organic extracts on DNA damage in primary cultured hepatocytes in rats were tested with single cell gel electrophoresis assay. Comet length means and percentage of tail cell were observed. Results A total of 98 organic pollutants were detected in all samples including 60 in source water and 58 in drinking water. The pollutants were mainly esters, ketons, phenols, benzenes and the derivatives. Comet length means was found to be significantly higher ( P

Objective To understand the status of indoor air formaldehyde pollution in a certain city in China.Methods 50 newly decorated houses in a certain city were chosen and the formaldehyde concentration in indoor air in different types of room were determined.Results The formaldehyde concentrations in indoor air in 56.6% of the investigated 50 houses exceeded the State Standard.And the highest concentration was 1.05 mg/m3 which was 10.5 times of the limit in the State Standard.Child's bedrooms were most seriously polluted,73% of which exceeded the State Standard.Conclusion The status of indoor air formaldehyde pollution in the newly decorated houses in a certain city in China is serious,this problem needs to be paid more attention to.

90%.Then the purified sertoli cells were treated with the toxicants at different dose,i.e.DBP(0.1,1,10,100,500 ?g/ml),BaP(0.01,0.1,1,10,50 ?g/ml)and their combination DBP+BaP(0.1+0.01,1+0.1,10+1,100+10,500+50 ?g/ml).The viability of sertoli cells was determined by MTT method and the lactate concentration in the cultured medium was detected.Results As compared with DMSO control,the absorbance values in 100 ?g/ml DBP and DBP+BaP(100+10 ?g/ml)groups were significantly increased(P0.05).Lactate concentration in 100,500 ?g/ml DBP groups,50 ?g/ml BaP group and DBP+BaP(100+10,500+50 ?g/ml)groups were increased(P

Objective To explain the physiological properties of serum leucine aminopeptidase (LAP) and discuss the different levels and clinical meaning of serum LAP during the second and the third trimester of gestation.Methods Rate turbidimetry was used to assay serum LAP activity of 175 pregnant women in the second trimester of gestation, among whom 162 were normal and 13 were intrahepatic cholestasis of pregnancy (ICP), and 302 pregnant women in the third trimester of gestation, among whom 215 were normal, 76 were ICP, 6 were pregnancy-induced hypertension syndrome and 5 were premature delivery, and 100 healthy or non-pregnant women.Results Serum LAP activity of pregnant women in the group of the second trimester of gestation was (140.43?64.39) U/L, in the group of the third trimester of the gestation was (234.72?93.53) U/L, and in control group was (72.62?15.31) U/L. The serum LAP activities of the two pregnant groups were much higher than that of control group (P

Objective To investigate the safety of trial of labor after cesarean (TOLAC) and clinical factors associated with successful TOLAC and to compare TOLAC with elective repeat caesarean section (ERCS) in terms of obstetric and neonatal outcomes.Methods A prospective cohort study was conducted among gravidas who had a history of lower segment cesarean section and were hospitalized in the Department of Obstetrics and Gynecology,the Affiliated Drum Tower Hospital of Medical School of Nanjing University from January to December 2014.Exclusion criteria included indications for caesarean section (such as placenta previa,placenta accreta,twin pregnancy,breech presentation and severe preeclampsia),serious maternal complications after cesarean section,lower uterine segment thinner than 3 mm and poor healing of uterine incision.Totally,287 gravidas were enrolled.Among them,142 chose TOLAC and the other 145 requested ERCS.Clinical data of those gravidas were collected and statistically analyzed by t-test,Log-rank test,Chi-square or Fisher's exact test.Results (1) The success rate of TOLAC was 90.8％ (129/142).There was no significant difference in maternal age,gestational age,thickness of lower uterine segment,interval between the two deliveries and neonatal birth weight and asphyxia rate between the successful (n=129) and unsuccessful (n=13) groups (all P＞0.05).Although the two groups had no significant difference in postpartum hemorrhage (PPH) rate,the gravidas who failed in TOLAC lost more blood than those who succeeded [425 (195-675) vs 200 (50-1 400) ml,P＜0.05].Moreover,higher amniotic fluid contamination rate was observed in the unsuccessful group [6/13 vs 17.1％ (22/129),P＜0.05].In the TOLAC group,99.3％ (141/142) were under continuous fetal heart rate monitoring.Incomplete uterine rupture occurred in one women without serious maternal or neonatal outcomes.The reasons for 13 failed TOLAC cases were unbearable pain during labor,abnormal labor,fetal distress and threatened rupture of uterus.(2) Compared with the ERCS group,the TOLAC group showed shorter interval from last cesarean section to the indexed delivery[5 (2-18) vs 6 (2-19) years],younger maternal age [(31±4) vs (33 ±4) years old] and less blood loss [200 (50-1 400) vs 300 (100-1 500) ml] (all P＜0.05).Conclusion Our study shows that,those who preferred TOLAC were younger,or had shorter pregnancy interval from last cesarean section.The success rate of TOLAC is high for women undergoing systematic prenatal assessment and close management during labor with less blood loss and non-serious maternal and neonatal complications compared with ERCS.

Objective:To study the clinical feasibility and advantages of the RapidPlan module based on Halcyon 2.0 ring medical linear accelerator in the design of volumetric modulated arc therapy (VMAT) plans after cervical cancer surgery.Methods:The data of 98 clinical cervical cancer cases were selected from the database, and VMAT artificial radiotherapy plans were designed based on Halcyon 2.0. Then, the designed plans were imported into the RapidPlan module to train the module for a prediction model with high goodness of fit. Another 20 patients after cervical cancer surgery were selected as the validation set to compare the differences in dosimetry, plan consistency, and plan execution efficiency between the manual plans and RapidPlan automatic plans.Results:The RapidPlan automatic plans could obtain dose distribution of target volume and organs at risk with the same quality as the manual plans. The RapidPlan automatic plans provided slightly inferior protection of the femoral head but superior protection of the spinal cord compared to the manual plans, and the difference was statistically significant ( t = 4.71, P<0.001). The average MU of the RapidPlan automatic plans was 687.46, which was lower than that of the manual plan (815.34), and the difference was statistically significant ( t = 6.09, P < 0.05). The portal dosimetry (PD) verification revealed that the average γ passing rate (1 mm/1%) of the RapidPlan automatic plans was 89.48%and that of the manual plans was 88.22%, and the difference was statistically significant ( t = 3.35, P < 0.05). Conclusion:RapidPlan automatic plans based on the Halcyon 2.0 platform can meet the clinical needs of the VMAT program for cervical cancer and has certain advantages.

Objective:To discuss the design details of accelerator room for a novel enclosed O-ring linac Halcyon, and to optimize its protection and layout.Methods:According to the optimization principle of radiation protection and the requirements of national radiation protection standards, and the structural characteristics of Halcyon accelerator, the differences between conventional and this novel accelerator rooms were analyzed by discussing the space layout of the machine room, shielding calculation, electrical facilities, purifying ventilation, temperature and humidity control and other factors.Results:The Halcyon machine had a compact structure, a closed ring frame design and a main beam shielding device, which could greatly reduce the radiation protection pressure while improving the space utilization rate of the machine room. The optimized design layout of the machine room could eliminate hidden dangers, avoid design defects, and prevent adverse consequences caused by design errors.Conclusions:The overall structure of Halcyon accelerator is different from that of conventional accelerators. The design details should be taken into full consideration to ensure the optimization of radiation protection, lay a good foundation for subsequent installation, debugging and operation of the equipment and create a good treatment environment for patients and medical staff.

Objective To explore and establish accurate detection quality control method of source positioning and timer precision for afterloading equipment. Methods The source positioning detection device was made of hd camera,EBT3 disposable film and steel rule,collecting source in each resident point for video images and film. Accurate measurement of radioactive source positioning and timer accuracy, including the timing absolute error and linear error through analysis of image sampling rate. After the film grayscale distribution analysis,comparison between film gray peak position and the measurement of resident point geometry,got the stay point source physics and radiation center deviation. Results Radioactive source physics and radiation center deviation was (-0.33± 0. 10) mm;For all default dwell time,timer average absolute deviation was (0.22±0. 02) s,linear fitting result was y=x-0. 226,R2=1,timing linear error was-0. 01％ Conclusions established detection means through the video images and film exposure quantitative analysis for accurately determination of source positioning,dwell time and source radiation center precision. After experimental testing the machine precision satisfied the requirement of clinical use.

Objective: To investigate the association between aflatoxin exposure and primary hepatocellular carcinoma (PHC) development. Methods: From December 2013 to May 2016, we selected 214 patients newly diagnosed with PHC as cases, and 214 patients as controls from three hospitals in Chongqing. Cases were confirmed with PHC diagnosis standard. And cases caused by clear reasons such as drug-induced liver injury, alcoholic liver damage, fatty liver and gallstones etiology, were excluded. Controls were included with no cancer and no digestive system disease, and recruited simultaneously with cases. Cases and controls were frequency-matched (1∶1) by same gender and age (±3 years). Peripheral blood and random urine samples were collected and analyzed for serum HBsAg status by biochemistry analyzer, and serum AFB₁-ALB adduct and urinary AFB₁-N⁷-GUA adduct by ELISA. Basic information, living habits and history of disease for patients were obtained by questionnaires. We used wilcoxon rank sum test to compare the median of serum AFB₁-ALB adduct and urinary AFB₁-N⁷-GUA adduct in cases and controls. Logistic regression analyses were performed to assess risk factors for PHC, and synergism index (S) of aflatoxin with other factors was estimated by the method of Andersson. Results: There was no significant difference in age between PHC cases (50.74±9.67) years and controls (51.15±9.90) years. Logistic regression showed that the odds ratio of HBV infection for PHC development was 46.3 (95% CI: 23.3-88.0). There was a significant difference in median concentrations of serum AFB₁-ALB adduct (cases vs controls: 146.23 vs 74.42 ng/g albumin, P<0.001), but no difference in median concentrations of urinary AFB₁-N⁷-GUA adduct was observed (cases vs controls: 0.17 vs 0.14 ng/mg creatinine, P<0.210). The odd ratios for PHC risk after adjustment were 1.9 (95%CI: 1.1-3.4) for AFB₁-ALB adduct, and 2.1 (95%CI: 1.0-4.2) for AFB₁-N⁷-GUA adduct. Moreover, we observed a positive interaction of aflatoxin exposure with HBV, alcohol drinking, and diabetes. The S was 4.7 (95%CI: 2.8-7.9), 3.5 (95%CI: 1.0-12.0), and 12.4 (95%CI: 1.8-84.2), respectively for serum AFB₁-ALB adduct with each of the three factors mentioned, and was 1.9 (95%CI:1.1-3.1), 2.0 (95%CI: 1.1-3.6), and 2.0 (95%CI: 1.1-3.6), respectively for urinary AFB₁-N⁷-GUA adduct with each of the three factors mentioned. Conclusion HBV was still the main risk factor, and AFB₁ exposure was also an independent risk factor for PHC in Chongqing. There was a positive interaction of aflatoxin with HBV, alcohol drinking, and diabetes.

Objective:To study the feasibility of using pelvic iterative cone beam CT images for dose calculation of radiation therapy planning, so as to provide support for adaptive radiotherapy.Methods:The CIRS 062 M phantom was scanned by Varian Halcyon v2.0 o-ring accelerator, and the average CT number under different scattering conditions was calculated, and then the ICBCT-ED conversion curve was established. CT images of CIRS 002PRA pelvic IMRT phantom and ICBCT images at different positions were collected. Treatment plan using VMAT technique based on CT image was designed and transplanted into ICBCT image with dose recalculated. The differences of gamma passing rate among target volume, organs at risk and 3-dimensional dose were compared. Based on the actual treatment plan of patients, the differences of 3-dimensional dose gamma passing rate in 10 pelvic patients were analyzed retrospectively.Results:There was a large CT value deviation at central position between the isolated no-scattering condition and the full-scattering condition, and the maximum deviation was 144 HU. The CT values of other positions in full-scattering condition were similar to those of the central position, and the maximum deviation was less than 50 HU. Based on the calculated result of ICBCT images at different positions of the pelvic phantom, the dose deviation of the target volume or organs at risk was less than 1 Gy. Compared with the plan based on CT images, the average 3-dimensional dose gamma passing rate under the criteria of 1% dose difference (DD)/1 mm distance-to-agreement (DTA) and 2% DD/2 mm DTA in plan based on ICBCT images were (88.86 ±1.18)% and (98.38±0.89)%, respectively. The ranges of average 3-dimensional dose gamma passing rate under the criteria of 2% DD/2 mm DTA and 3% DD/3 mm DTA in 10 patients with pelvic tumors were 90.03%-95.43% and 93.58%-97.78%, respectively, and the worst result was only 85.90% and 92.90%, respectively. The main reason of the worst result was the dose difference caused by large variation of bladder contour due to over-filling.Conclusions:Under comprehensive scattering conditions, the ICBCT-ED conversion curve is reconstructed and the treatment plan can be designed by using the ICBCT image of Halcyon v2.0 linear accelerator. The accuracy meets the standards of clinical application, which provides assurance for adaptive radiotherapy in the future.