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Objective:To assess the effects of low-dose ionizing radiation on the thyroid of medical radiation workers.Methods:Based on the inclusion and exclusion criteria, 27 articles, involving 22 937 individuals, were screened finally from relevant literature published from 1996 to 2022. Meta-analysis was carried out using Stata 16.0 for serum levels of triiodothyronine (T 3), free triiodothyronine (FT 3), thyroid hormone (T 4), free thyroid hormone (FT 4), thyrotropin-stimulating hormone (TSH) and thyroid nodule rates. As well, subgroup analysis were carried out of thyroid function in different types of radiation workers. Results:The standardized mean difference (SMD) at T 3 and T 4 levels for radiation workers was -0.19 (-0.37, -0.01) and -0.34 (-0.38, -0.30), lower than that of control group ( Z=2.07, -16.06, P<0.05). The SMD at FT 4 levels for radiation workers was 0.22 (0.06, 0.39), higher than control group ( Z=2.61, P<0.05). The relative risk of thyroid nodules in radiation workers was 1.47 (1.19, 1.82), higher than that of control group ( Z=-3.58, P<0.05). The analysis result for subgroup showed that the SMD for T 3, T 4 and TSH levels in the interventional radiology workers were -0.29 (-0.51, -0.07), -0.31 (-0.47, -0.15) and -0.43 (-0.73, -0.13) ( Z=-2.55, -3.86, -2.82, P<0.05), respectively, and the SMD for T 4 levels in the nuclear medicine workers was -0.26 (-0.45, -0.07), which meaned a reduced risk compared to the control group ( Z=-2.70, P<0.05). Conclusions:Long-term low doses of ionising radiation may have adverse effects on thyroid hormone and thyroid nodule in radiation workers, particularly in interventional radiology workers, and attention should be focused on their radiation protection.
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@#<b>Objective</b> To investigate radiation resources in medical diagnosis and treatment and their use frequency in medical institutions in Hangzhou, China, and to provide a basis for relevant departments to rationally allocate and scientifically supervise the resources. <b>Methods</b> From April 1, 2019 to March 31, 2020, a survey was conducted on the basic information, radiation staff, equipment configuration, and frequency of radiation diagnosis and treatment of all medical institutions in Hangzhou using a questionnaire. <b>Results</b> There were 1001 institutions with radiation services in Hangzhou, with 6714 radiation staff members and 2742 pieces of radiation equipment. The frequency of conventional X-ray diagnosis was 788.43 per 1000 population. The frequency of computed tomography diagnosis was 531.93 per 1000 population. The frequency of mammography and dental photography diagnosis was 246.34 per 1000 population. The frequency of interventional diagnosis and treatment was 10.01 per 1000 population. The frequency of radiotherapy was 2.39 per 1000 population. The frequency of nuclear medicine diagnosis was 8.90 per 1000 population. The frequency of nuclear medicine treatment was 0.99 per 1000 population. <b>Conclusion</b> Medical institutions have developed rapidly in Hangzhou, but with an unbalanced situation. In order to better protect the health of examinees, we recommend relevant departments optimize resource allocation and strengthen supervision on radiation protection in medical institutions.
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Objective To explore the absorbed dose to the common tissues of subjects in four clinical CT scanning modes and the spatial distribution of the radiation field in chest scanning, in order to provide a basis for the radiation protection of subjects and the space in the machine room. Methods A thermoluminescence detector (TLD) was used to measure the absorbed doses to the eye lens, thyroid gland, gonad, chest and abdominal skins of the anthropomorphic phantom in four CT scanning modes. The TLD was used to monitor the air kerma at different positions from the CT diagnostic table during chest spiral scanning. Results The absorbed doses to the eye lens, thyroid gland, gonad, chest and abdominal skins of the anthropomorphic phantom in four CT scanning modes were 0.040-64.818 mGy, 0.154-10.155 mGy, 0.028-0.154 mGy, 0.443-17.141 mGy, and 0.093-14.346 mGy, respectively. The maximum air kerma value of the space radiation field during chest scanning was 0.049 mGy, and the farther the distance from the CT tube, the smaller the value. Conclusion The absorbed doses to the common tissues of subjects examined by the four CT scanning modes generally do not exceed the threshold doses. The dose received by the companion of the subject during a single chest CT scan was small. In order to minimize radiation hazards, shielding measures can be taken in CT scanning to reduce the absorbed doses to the tissues of the subject, and the companion of the subject should appropriately increase the distance from the tube and the diagnostic table.
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Objective@#To investigate the health status of radiation workers in a city and provide evidence for the health management of radiation workers.@*Methods@#To investigate the health status of radiation workers in a city and provide evidence for the health management of radiation workers.@*Results@#The majority of radiation workers are engaged in diagnostic radiology, male is more than female. The abnormal rate of micronuclear (0.59‰) and chromosome aberration (0.47%) was highest in nuclear medicine workers. The abnormal rate of micronuclear and chromosome aberration was similar with interventional and diagnostic radiology. Expect for micronuclear (χ2=32.945, P<0.01) and chromosome aberration (χ2=75149.737, P<0.01) , other radiation sensitive indicators have no difference. The abnormal rate of thyroid function (18.8%) (χ2=12.084, P<0.01) , micronuclear (0.25‰) (χ2=57.359, P<0.01) , chromosome aberration (0.08%) (χ2=17.209, P<0.01) in group whose service length exceeding 20 years was higher than other service length groups. There is no statistical difference in other radiation sensitive indicators among different service length group.@*Conclusion@#Long-term low doses of ionizing radiation could affect radiation worker's health, expecially radiation workers engaged in nuclear medicine and radiotherapy. We must pay attention to occupaitonal health care and management to ensure radiation worker's health.
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Objective To evaluate the function of regulatory T (Treg)cells in peripheral blood from patients with psoriasis, and to explore the possible role of the STAT3 signaling pathway in Treg cell dysfunction. Methods Totally, 81 patients with psoriasis vulgaris, who all presented with chronic plaques and had a psoriasis area and severity index (PASI)score of 10 - 30, were enrolled into this study. Forty-six healthy blood donors served as the control group. Venous blood samples were collected from these subjects followed by isolation of Treg cells and responder T (Tresp)cells. Flow cytometry was performed to determine the proportion of Treg cells in peripheral blood as well as that of cells secreting phosphorylated-STAT3(p-STAT3), interferon γ(IFN-γ), tumor necrosis factor α(TNF-α)and interleukin 17(IL-17)in Treg cells, and quantitative real-time PCR (qRT-PCR)to measure the expression levels of IFN-γ, TNF-α and IL-17 mRNAs in Treg cells. Some Treg cells and Tresp cells were cultured in vitro alone or in combination, and flow cytometry was conducted to estimate cellular proliferative activity on day 7 after stimulation with IL-2. Some patient-derived Treg cells were classified into several groups to be cultured alone or in combination with Tresp cells with or without the presence of the STAT3 pathway inhibitor, Stattic V (10 or 50 μg/L), for 7 days. Subsequently, flow cytometry was performed to evaluate the proliferative activity of Tresp cells, and qRT-PCR to measure the expression levels of IFN-γ, TNF-α and IL-17 mRNAs in Treg cells. Results No significant differences were observed in the proportion of Treg cells in peripheral blood between the patient group and control group (6.437% ± 0.186% vs. 6.812% ± 0.241%, t = 1.224, P >0.05). Compared with control-derived Treg cells, the patient-derived Treg cells showed significantly decreased proliferative activity and inhibitory effects on Tresp cells, but increased proportion of cells secreting p-STAT3, IFN-γ, TNF-α and IL-17 (all P < 0.05). After the treatment with 50 μg/L Stattic V, a significant increase was observed in the inhibitory effect of patient-derived Treg cells on Tresp cells (inhibition rate: 61.670% ± 4.640% vs. 28.820% ± 11.490%, P < 0.05), but a significant decrease in the mRNA expressions of IFN-γ (2-△△C t: 1.654 ± 0.879 vs. 23.350 ± 6.721, P <0.05), TNF-α(0.850 ± 0.705 vs. 4.847 ± 1.525, P < 0.05)and IL-17(0.572 ± 0.135 vs. 3.095 ± 0.650, all P < 0.05)in patient-derived Treg cells compared with untreated patient-derived Treg cells. Conclusions The negative regulatory effect of Treg cells on Tresp cells is decreased in patients with psoriasis, which may be associated with abnormal activation of the STAT3 signaling pathway, and inhibition of the pathway may restore the function of Treg cells to a certain extent.
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Objective:To introduce 3 methods for preparation of stomach-conserving gastroesophageal reflux disease(GERD)model in rats,so as to improve the quality and successful rate of model preparation.Methods: Male Sprague-Dawley rats were divided into sham-operated(SO) group(n=20) and 3 stomach-conserving reflex model groups: duodenogastroesophageal reflux(DGER)group(n=47,esophagogastroduodenal anastomosis),gastroesophageal reflux(GER)group(n=20,partial pyloric ligation + cardiomyotomy followed by gastric fundus-esophagus anastomosis) and duodenoesophageal reflux(DER) group(n=21,jejuno-esophageal anastomosis followed by duodeno-esophageal anastomosis).Rats were observed closely after operation and their body weights were monitored.The rats that died unexpectedly were autopsied immediately and the surviving rats were sacrificed to observe the esophageal pathological changes at 1,2,3,and 4 months after operation.Results: Three rats died due to anesthetic accidents;26(24.1%) died unexpectedly after operation,18(38.3%)in DGER group,1(5%) in GER group,and 7(33.3%)in DER group;no rat died in SO group.Necropsy showed that the death cause of rats included obstruction,infection,asphyxia,hemorrhage,anastomosis leakage and perforation,etc.Esophageal pathological changes were noticed in all rats of 3 model groups;the life quality of surviving rats was good.Conclusion: The 3 methods for establishing rat stomach-conserving GERD model can produce high quality model and high rate of pathological changes,but with high post-operation mortality.In addition to rational operative methods,avoiding post-operation complications and unexpected death are also very important for successful GERD model preparation.