Objective To investigate the bone protective effects and underlying mechanisms of 900MHz radiofrequency radiation (RF) at different power densities (50, 150, and 450 μW/cm²) on an ovariectomy-induced osteoporosis mouse model. Methods Sixty 3-month-old C57BL/6 female mice were randomly divided into Sham group (sham exposure), OVX group (ovariectomy), OVX + LRF group (OVX + 50 μW/cm² RF), OVX + MRF group (OVX + 150 μW/cm² RF), OVX + HRF group (OVX + 450 μW/cm² RF), and OVX + E2 group (OVX + estradiol). Ovariectomized mice in the OVX + RF groups were exposed to RF of varying power densities for 4 hours daily. Ovariectomized mice in the OVX + E2 group received intramuscular injections of estradiol (0.04 mg/kg) every two days. After four weeks of intervention, Micro-CT, ELISA, RT-PCR, and immunohistochemistry were employed to analyze bone density, bone microstructure, serum bone metabolic markers, and the expression of related genes and proteins. Results Compared with the Sham group, the OVX group showed significantly decreased bone mineral density (BMD) and bone microstructure indicators such as BV, BV/TV, Tb.Th, and Tb.N, significantly increased bone microstructure indicator Tb.Sp, significantly decreased serum estradiol, significantly increased serum CTX-I, TRACP-5b, BGP, and OPG, significantly increased Nfatc1 and Runx2 mRNAs, and significantly increased OPG and RANKL. Compared with the OVX group, the OVX + MRF group and OVX + E2 group exhibited significantly increased BMD, BV, BV/TV, Tb.Th, and Tb.N, significantly decreased Tb.Sp, significantly increased serum OPG, Runx2 mRNA, and OPG, and significantly decreased serum CTX-I, TRACP-5b, Nfatc1 mRNA, and RANKL. Compared with the OVX group, the OVX + LRF group showed significantly increased cortical bone BMD and Tb.Th, the OVX + HRF group showed significantly increased cortical bone BMD and serum CTX-I and TRACP-5b, and the OVX + MRF group showed significantly increased serum BGP. Among the three power densities, the 150 μW/cm² RF showed the most significant effect. Conclusion The 150 μw/cm² 900 MHz RF can counteract the abnormalities in serum bone metabolism biomarkers, the decrease in BMD, the degeneration of bone microstructure, and the increase in bone resorption caused by ovariectomy in mice.

Objective To investigate the role and related mechanisms of exosomes derived from mesenchymal stem cells (MSCs) in radiation-induced lung injury (RILI). Methods Human umbilical cord-derived MSCs were isolated and cultured for the extraction and identification of exosomes. Eighteen male SD rats were randomly divided into Control group, RILI group and RILI + exosomes group (EXO group), with 6 rats in each group. Except for Control group, the other groups received a single X-ray dose of 30 Gy to the right lung. Immediately after irradiation, the EXO group was administered 2 × 10⁹ exosomes/kg via tail vein injection. Control group and RILI group were given the same volume of normal saline. Eight weeks post-irradiation, the rats were sacrificed, lung tissue and peripheral venous blood were collected. HE and Masson staining were employed to observe the pathological and fibrotic changes of lung tissue. The levels of serum inflammatory factors IL-6, IFN-γ, TNF-α, and IL-10 were detected by ELISA. RT-qPCR was used to assess the mRNA levels of IL-1β, IL-6, Cdh1, and Col1a1 in lung tissue. The expression levels of Vimentin and TGF-β1 in lung tissue were measured by immunohistochemical staining. The expression levels of AMPK, p-AMPK, and TGF-β1 in lung tissue were detected by Western blot. Results MSC-derived exosomes were successfully extracted and identified. Compared with RILI group, EXO group showed significantly reduced pathological changes of lung inflammation and collagen deposition. The levels of serum inflammatory factors IL-6, INF-γ, and TNF-α were significantly decreased (P < 0.05), and the level of anti-inflammatory factor IL-10 was significantly increased (P < 0.05). The mRNA levels of IL-1β, IL-6, and Col1a1 in lung tissue were significantly decreased (P < 0.05 or P < 0.01), and the mRNA level of Cdh1 was significantly increased (P < 0.05 or P < 0.01). The levels of Vimentin and TGF-β1 in lung tissue were significantly reduced, while p-AMPK level was significantly up-regulated (P < 0.05). Conclusion Exosomes derived from MSCs may alleviate RILI by inhibiting inflammatory responses and regulating epithelial-mesenchymal transition mediated by AMPK/TGF-β1 signaling pathway.

Objective To establish a model of radiation-induced myocardial fibrosis in mice, and study the effect of TGF-β/SMAD pathway on radiation-induced myocardial fibrosis in mice and the protective effect of pirfenidone capsules (PFD) on radiation-induced myocardial fibrosis. Methods Male C57BL/6J mice were randomly divided into control group, irradiation group, and drug intervention groups (low-dose PFD + irradiation group and high-dose PFD + irradiation group). After radiation exposure, the control group and the irradiation group were given sodium carboxymethyl cellulose by gavage, while the low-dose PFD + irradiation group and the high-dose PFD + irradiation group were given PFD at 150 and 300 mg/kg daily by gavage for 12 consecutive weeks, respectively. The body weights of mice were measured and recorded weekly. The pathological changes of heart tissues in mice were observed by H&E and Masson’s trichrome staining. The expression levels of TGF-β, SMAD2, and SMAD3 mRNAs in mouse heart tissues were detected by RT-PCR. The expression levels of TGF-β, SMAD2, and SMAD3 proteins in mouse heart tissues were detected by Western blot. The expression levels of CK and CK-MB in mouse heart tissues were detected by blood biochemical tests. Results H&E and Masson’s trichrome staining showed severe myocardial fibrosis in the irradiation group compared with the control group. Compared with the irradiation group, the two groups with drug intervention showed reduced heart disease and myocardial fibrosis. RT-PCR and Western blot showed that the expression levels of TGF-β, SMAD2, and SMAD3 were up-regulated in the irradiation group compared with the other three groups (P < 0.05). The expression levels of TGF-β, SMAD2, and SMAD3 were down-regulated in the two groups treated with PFD compared with the irradiation group (P < 0.05). The expression levels of CK and CK-MB in mouse heart tissues were down-regulated in the two groups treated with PFD compared to irradiation group (P < 0.05). Conclusion Radiation has long-term effects on normal heart tissue, causing myocardial damage and promoting myocardial fibrosis. The up-regulation of TGF-β/SMAD pathway is related to the formation of radiation-induced myocardial fibrosis. PFD can mitigate the progression of myocardial fibrosis and protect heart tissue by down-regulating TGF-β/SMAD pathway.

Objective To analyze the distribution characteristics and trends of occupational exposure types of medical radiation workers in Gansu Province, China, and to provide a basis for administrative departments to formulate and adjust radiation protection policies. Methods According to the radiation health information platform, the data of occupational exposure types of radiation workers in Gansu Province from 2014 to 2023 were obtained. The proportions of occupational exposure types in each physical examination year was statistically analyzed. Results From 2014 to 2023, the number of medical radiation workers accounted for more than 70% of the total number of radiation workers. The proportion of X-ray imaging diagnostic radiation workers in the total number of medical radiation workers gradually decreased but remained the highest, exceeding 68% annually. The proportion of interventional radiology workers in the total number of medical radiation workers increased from 13.8% to 25.5%. The proportions of radiation therapy and nuclear medicine workers in the total number of medical radiation workers increased slowly. The numbers of interventional radiology and radiotherapy workers in tertiary hospitals both accounted for more than 70% of the total number of such workers in the province. The proportion of interventional radiology workers increased and then decreased. The proportion of radiotherapy workers increased significantly from 70.5% to 93.0%. The number of nuclear medicine workers in tertiary hospitals accounted for more than 80% of such workers in the province. Conclusion Radiation protection policies and measures should be adjusted according to the changes in the types of occupational exposure. The focus of these policies and measures should differ depending on the level of healthcare institutions, the type of radiological diagnostic and therapeutic services, and the characteristics of various occupational exposure types .

Objective To assess and understand the service capabilities and existing problems of radiation health technical service institutions in Jiangsu Province, China, and provide a basis for improving in-process and post-process supervision as well as enhancing radiation health technical service capabilities. Methods Thirty radiation health technical service institutions in Jiangsu Province were selected as quality monitoring objects from the National Occupational Health Technical Service Institution Management Information System. Evaluations were conducted using a standardized national assessment checklist, and a comprehensive risk assessment was performed by combining the results of laboratory test capability comparisons. Results The 30 institutions all passed the quality monitoring, with an average score of （76.62 ± 5.07）. Comprehensive risk assessment identified 8 (26.67%) high-risk institutions, 22 (73.33%) medium-risk institutions, and 0 (0%) low-risk institutions. Conclusion The overall service quality of radiation health technical service institutions in Jiangsu Province is acceptable. However, further training and supervision are needed to improve technical service capacity and reduce service risks.

Objective To investigate the awareness of radon exposure hazards among non-uranium miners in Chongqing, China. Methods A survey was conducted among 177 male miners from eight non-uranium metal mines in Chongqing to collect data on basic information, personal habits, and the rate of radon awareness. Factors affecting radon awareness were analyzed using chi-square test and logistic regression model. Results The awareness rate of radon among miners was 23.73%. The chi-square test indicated significant difference in the radon awareness rate among miners with different levels of education (χ² = 10.28, P < 0.05), while there was no significant difference across different ages, years of work, labor relations, job categories, and types of miners (P > 0.05). Binary logistic regression analysis showed that a college (junior college) or higher level of education, a high school level of education, and working in mines were factors affecting the radon awareness among miners (χ² = 4.030, 9.150, 11.776, P < 0.05). Conclusion Miners lack awareness of radon, and there is an urgent need to strengthen education and propaganda regarding the hazards of radon.

Objective To investigate and analyze the occupational stress levels and influencing factors among radiation workers in China, and provide a reference for alleviating occupational stress and promoting mental health. Methods Using the general situation questionnaire, Effort-Reward Imbalance questionnaire, and radiation protection knowledge questionnaire, a convenience sampling method was adopted to investigate the occupational stress of 243 radiation workers in Liaoning, Fujian, Guangdong, and Xinjiang provinces. The independent samples t-test, one-way analysis of variance, chi-square test, and binary logistic regression were used to analyze the influencing factors. Results The average score of Effort-Reward Imbalance was 0.97 ± 0.22, and 100 (41.15%) radiation workers had occupational stress. There were significant differences in the detection rate of occupational stress among radiation workers of different ages, working years in radiation positions, monthly incomes, daily sleep durations, and daily working hours (P < 0.05). Logistic regression analysis identified daily working hours as a factor contributing to occupational stress. Conclusion The occupational stress among radiation workers in China is relatively severe. It is recommended to pay attention to the associated risks and implement targeted intervention measures to reduce the impact of occupational stress.

Objective To verify the accuracy of γ spectrometry by analyzing the results of national interlaboratory comparisons of radionuclide analysis by γ spectrometry from 2018 to 2023. Methods A statistical analysis was conducted on the results from multiple years of participation in the national interlaboratory comparisons of radionuclide analysis by γ spectrometry. The measurement results of radionuclide specific activities in soil were analyzed to provide technical support for improving the capability to analyze radionuclides in soil. Results The laboratory participated in six interlaboratory comparisons and conducted 23 radionuclide analyses by γ spectrometry from 2018 to 2023. The relative deviation was −12.20% to 8.11%, the |Z_test| was 0 to 0.61, the U_test was 0 to 0.62, and the U_rel was 0.07 to 0.12. The overall pass rate was 100% and the excellent rate was 33.3%. In addition, 21 of the 23 (91.3%) radionuclide analyses showed full scores in experiment operation. However, the total scores were relatively low due to multiple oversights and lack of rigor in the preparation of the test reports, which prevented the laboratory from qualifying for the excellence evaluation process, resulting in a relatively low excellent rate. Conclusion The interlaboratory comparisons indicate that the measurements of radionuclides in this laboratory were all qualified, with full scores for experiment operation in several analyses. These results demonstrate that the soil radionuclide analysis system based on γ spectrometry is reliable and stable.

Objective Emergency response to public health emergencies constitutes a vital component of the modernization of national governance systems and capacities, directly impacting national security, social stability, and public health. This study aims to analyze the key issues and research hotspots in the field of emergency response to public health emergencies, providing theoretical foundations and practical guidance for formulating scientific and effective emergency strategies and policies. Ultimately, it seeks to enhance the nation’s capability to respond to public health emergencies and safeguard public health. Methods Using core journals indexed in the China National Knowledge Infrastructure (CNKI) database as the data source, 1094 journal articles in the field of emergency response to public health emergencies in China from 2003 to September 2024 were selected as the research sample. Citespace visualization software was employed to organize and analyze the research process in the field of emergency response to public health emergencies. Results The current research in this field predominantly involves small-scale cooperation, and the research process can be divided into four stages. The research in the emerging stage mainly focuses on the themes of emergency mechanism and emergency management, the development stage mainly centers on the themes of emergency capacity improvement and system exploration, the outbreak stage emphasizes the themes of COVID-19 and epidemic prevention and control, and the sustainable development stage highlights collaborative governance and informatization. Conclusion The COVID-19 pandemic has accelerated the development of research in this field. Currently, the field shows a continuous growth, with an increasing volume of publications. The focus of current research has shifted towards collaborative governance and the study of assessment tools, aiming to enhance the efficiency and effectiveness in responding to public health emergencies. Moreover, the field is advancing toward more systematic and comprehensive research. However, there is still a need to strengthen scientific communication and collaboration.

Objective To identify issues and summarize experiences through the analysis and discussion of the current measurement comparison activity, and to improve the radiation detection ability of the social radiation environment detection institutions in Jiangsu Province, China. Methods Fixed measurement points were established. The institutions were assigned to different groups and carried out measurements one-by-one on site. For cosmic ray response value, each institution measured and recorded 50 original data; for γ dose rate in fields, roads, and indoor environments, each reference institution measured and recorded 10 original data. The institutions calculated the monitoring results independently, and the organizer’s expert group checked the results to ensure that there were no calculation errors. Gross errors were eliminated by Grubbs test, and the comparison results were evaluated by Z-score method (median/normalized interquartile range). Results Among the 75 measurement results (excluding the cosmic ray response values), 94.7% were rated as “satisfactory”, 5.3% as “problematic”, and none as “unsatisfactory”. The “problematic” results involved two FH40G γ radiation dose rate meters and one AT1121 γ radiation dose rate meter. Conclusion The cosmic ray response value of the instrument does not necessarily affect the comparison and evaluation of environmental γ radiation dose rate measurement results. AT1121 γ radiation dose rate meter may not be suitable for measuring the air-absorbed dose rate of γ radiation in general environment.