The cancer risk and epidemiological analysis for medical X-ray workers in Shanghai / 中华放射医学与防护杂志

Objective:To study the risk of malignant tumor in medical X-ray workers in Shanghai and provide scientific data for the study on occupationally exposed population.Methods:A retrospective cohort study was conducted to investigate the risk of cancer. Totally, 715 physicians in radiology departments during 1950-1980 in Shanghai were selected as exposure group, while 738 with non-radiology departments in the same hospital in the same time period as control group. The basic information on the selected physicians and associated cancer incidence were collected. The comulative number of individuals with cancer from 1980 to 2021 was calculated. The relative risk ( RR) of cancer was analyzed using logistic regression model in terms of gender, birth year, and work starting year. As well, stratified analysis based on confounding factors was conducted. Results:A total of 1 369 individuals were followed up, including 668 in exposure group and 701 in control group. The cumulative person-year of observed individuals was 52 980. As of 31 December 2021, a total of 199 patients with various malignant tumors were identified. The results of the logistic regression analysis showed that the risk of malignant tumors in exposure group was significantly higher than that in control group. The adjusted RR of solid cancer and total cancer was 1.49 (95% CI: 1.08-2.05, P=0.015) and 1.40 (95% CI: 1.02-1.92, P=0.036), respectively. In addition, the risk of thyroid cancer in exposure group was significantly higher than that in control group ( RR=10.06, 95% CI: 2.05-49.62, P=0.005). Stratified analysis showed that the exposure group had a higher risk of total cancer both for femals and workers taking their jobs at age of 21-25. Conclusions:The risk of thyroid cancer, solid cancer and total cancer in the medical X-ray workers was significantly higher than that in control group. It is suggested that radiation protection in medical practice should be strengthened for the occupationally exposed workers, especially for femals and workers taking their jobs at low age.

Effectiveness of personal dose monitoring intercomparison results in a laboratory in Shanghai / 环境与职业医学

Background Individual monitoring of occupational external exposure is an essential part of the occupational health management of radiation workers, and is an important basis for the evaluation of individual absorbed dose and the diagnosis of occupational radiation diseases. Continuous participation of monitoring service providers in intercomparison is a fundamental quality assurance for routine monitoring, which can identify problems and improve them in time. Objective Taking the Laboratory of Radiation Protection in Shanghai Institute of Preventive Medicine as an example, to evaluate the performance of an individual occupational external dose monitoring system in the laboratory, identify influencing factors of the monitoring results, and provide a basis for improving the quality of daily monitoring by analyzing the process and results of a national intercomparison of individual dose monitoring. Methods According to the Testing criteria of personnel dosimetry performance for external exposure (GBZ 207-2016), and the relevant requirements of Class II (photon) inspection, a total of 20 groups of blind sample dosimeters were measured for four consecutive years from 2018 to 2021. The radiation energy source of each group was identified, and related personal dose equivalent Hp(10), the uncertainty of measurement results, and the deviation between the reported value and the reference value were calculated. The national intercomparison process and results of individual dose monitoring were also analyzed. Results The energy sources of the blind samples in the tested laboratory for four years were N100 or Cs-137. The reported dose values of the blind samples were 0.57-4.61 mSv, the combined uncertainties were 0.043-0.365 mSv, the expanded uncertainties (k=2) were 0.09-0.73 mSv, and the relative expanded uncertainties (k=2) were 13.8%-16.4%. The single-group performance ∣Pi∣ of 20 sets of blind samples in the four years was ≤0.10, the yearly comprehensive performance of 5 sets of blind samples was ≤0.10, and the yearly Q score of the test report was >15 points. The laboratory achieved excellent results in the national intercomparison of individual dose monitoring in four consecutive years, except the Q value not reaching full score. Conclusion The laboratory exhibits standardized data processing of individual dose monitoring, generates accurate and reliable results, and meets the requirements of relevant national standards; but it should continue to participate in the national intercomparison of individual dose monitoring, strengthen the angular response research of energy identified dosimeter, improve the monitoring ability of low-dose X-rays, analyze the key points of reducing the uncertainty of measurement results, and continuously improve the monitoring ability.

Internal exposure levels of thyroid 131I in nuclear medical staff / 环境与职业医学

Background Based on numerous epidemiological studies, radionuclide 131I can result in thyroid disease. Objective To study the contamination level of thyroid 131I in 131I treatment associated radiation workers in nuclear medicine departments in Shanghai. Methods Based on a general survey on basic situation of nuclear medicine in Shanghai, the level of internal exposure of radiation workers involved in 131I treatment was assessed with questionnaires and on-site monitoring. A portable γ spectrometer was used for on-site detection, the intake and annual effective dose were estimated according to the measurement results. Physical examination reports were collected for radionuclide positive workers, and chromosome testing was performed. Results There were 579 nuclear medicine workers and 175 were engaged in 131I treatment in Shanghai. 131I was detected in thyroid of 18 workers, with a detection rate of 10.3%. Among them, the detection rates of thyroid 131I in nurses and cleaners were 23% and 25% respectively. The mean measured activity of thyroid 131I was 306.1 Bq and the maximum measured activity was 3716.9 Bq (nurse). The maximum intake was estimated at 37544 Bq and the median was 786.4 Bq. The average annual committed effective dose was 1.22 mSv and the maximum value was 14.87mSv. The chromosomal aberration rates of all detected workers were negative, and all blood indicators were normal except one with low hemoglobin. Conclusion The annual dose of nuclear medical staff engaged in 131I treatment does not exceed the national standard limit, but the internal exposure of nurses and cleaners should not be ignored. On the basis of strengthening protection and decontamination, routine internal exposure monitoring should be carried out.

Feasibility study of predicting dose of radioiodine in hyperthyroidism patients based on neural network / 中华放射医学与防护杂志

Objective:To construct back propagation (BP) neural network model to predict the dose required for 131I therapy for hyperthyroidism and to calculate the personalized dose plan for patients. Methods:A complete set of data of patients treated for hyperthyroidism radioaiodine was collected from the nuclear medicine departments of several medical colleges in Shanghai, including history, examination result, treatment course, etc. As a result, a prediction model was established. The predicated result for BP neural network, radial basis function (RBF) neural network and Support Vector Machine (SVM) were compared by means of small sample data. The optimal model was selected to predict administrated dose and to finally test the accuracy of the model.Results:The average errors in BP neural network, RBF neural network and SVM model based on small samples were 5.53%, 7.09% and 9.64%, respectively. After comparison, BP neural network was selected to build the prediction model. 30 cases of data were selected by random sampling to verify the BP neural network. The mean error, mean square error, minimum error and maximum error of the prediction result were 7.22%, 0.053, 0.57% and 13.78%, respectively.Conclusions:In this study, a neural network prediction method was proposed to provide a more accurate dose for patients in need of radioiodine therap for hyperthyroidism, and to reduce the possibility of radiation damage or the unsatisfactory therapeutic effect caused by insufficient dose. It has clinical practical significance in providing the reference for clinicians to evaluate the administrated dose.

Clinical effect of omeprazole combined with antibiotics in the treatment of peptic ulcer / 中国基层医药

Objective To explore the efficacy and adverse reaction of combined application of omeprazole and antibiotics in treatment of peptic ulcer.Methods 92 peptic ulcer patients in our hospital from 2013 March to 2014 March were selected.According to treatment methods,they were divided into the observation group and control group,46 cases in each group.The control group was given cimetidine,amoxicillin metronidazole treatment;the observation group was given omeprazole,amoxicillin and metronidazole treatment.The clinical efficacy and adverse reactions of the two groups were analyzed.Results The clinical efficacy of the observation group after treatment was 93.48 ％,which was significantly higher than 78.26％ of the control group (x2 =8.930,P ＜ 0.05).The abdominal distention,stomach burning sensation grades of the observation group were significantly better than the control group (t =7.42,8.03,P ＜ 0.05).Conclusion The combined application of omeprazole and antibiotics has obvious effect in treatment of ulcer disease,and it is safe and reliable,which is worthy of clinical application.

Correlation of apolipoprotein M with severity of coronary artery stenosis in patients with coronary heart disease / 中华全科医师杂志

One hundred and thirty seven pafients diagnosed by coronary angiography were recruited in the study and divided into coronary heart disease group(CAD)and control group.Relationship between serum apolipoprotein M levels and the severity of stenosis of coronary arteries was analyzed.In covariate analysis,serum apolipoprotein M levels were significantly lower in CAD group than those in control group adjusted for sex,age,body mass index(BMI)(P＜0.05).By stepwise muhiple regression,serum levels of apolipoprotein M were correlated positively with BMI(r=0.65,P＜0.01),and correlated negatively with total cholesterol(TC)(r=-0.53,P＜0.01)and low density lipoproteins(LDL-C)(r=-0.42,P＜0.01).Serum levels of apolipoprotein M were correlated negatively with the score of coronary stenosis(r=-0.62,P＜0.01).The results suggest that apolipoprotein M might be related to the development of coronary artery disease.