Objective: To investigate the radon concentration and occupational radon exposure doses in Hangzhou Metro Line 1 and Line 5, so as to provide a basis for assessing potential health risks of radon exposure and protecting the occupational health of metro workers. Methods: From March 2022 to March 2023, radon concentration monitoring was conducted at 53 stations on Hangzhou Metro Lines 1 and 5. Four sampling points were set up at each station: train control room, customer service center, security checkpoint area, and platform. Continuous monitoring was conducted for one year at the train control room, while continuous monitoring at the other sampling points lasted for one quarter. CR-39 cumulative radon detection cups were used to measure radon concentrations, while RAD7 radon detectors were used to measure instantaneous radon concentrations. The annual effective dose to workers from radon and its progeny was estimated. Radon concentrations across different lines, sampling points, and seasons were analyzed. Results: The median radon concentration was 26.8 (interquartile range, 11.2) Bq/m3 in Line 1, and the median instantaneous radon concentration was 4.7 (interquartile range, 8.5) Bq/m3. In Line 5, the radon concentration was (26.1±6.1) Bq/m3, and the median instantaneous radon concentration was 4.7 (interquartile range, 7.4) Bq/m3. No significant differences were found between the two lines in either radon or instantaneous radon concentrations (both P>0.05). The control rooms in both lines showed relatively high radon levels, with a median of 42.5 (interquartile ranges, 24.3) Bq/m3 in Line 1 and a median of 26.8 (interquartile ranges, 6.1) Bq/m3 in Line 5. In the Line 1 control room, the median radon concentrations across four quarters were 37.7 (interquartile range, 27.5), 42.5 (interquartile range, 24.4), 46.8 (interquartile range, 26.0), and 34.9 (interquartile range, 29.0) Bq/m3, respectively. No significant seasonal variation was observed (P>0.05). In the Line 5 control room, the values were 24.8±6.7, 26.6 (5.9), 33.8±7.9, and 22.8 (8.7) Bq/m3, respectively. A significant seasonal difference was found (P<0.05), with the third quarter showing higher radon levels than the first and fourth quarters (both P<0.05). The annual effective doses to workers from radon and its progeny were relatively high in the Line 1 control room (0.305 2 mSv) and the Line 5 platform (0.255 9 mSv). Conclusions The radon concentrations in Hangzhou Metro Lines 1 and 5 were within the low-dose radiation range and met the national standard limits. No significant health risks were identified. However, attention should be paid to radon levels in control rooms and during the third quarter. Enhanced monitoring and ventilation management are recommended.

BACKGROUND: T cell dysfunction, which includes exhaustion, anergy, and senescence, is a distinct T cell differentiation state that occurs after antigen exposure. Although T cell dysfunction has been a cornerstone of cancer immunotherapy, its potential in transplant research, while not yet as extensively explored, is attracting growing interest. Interferon regulatory factor 4 (IRF4) has been shown to play a pivotal role in inducing T cell dysfunction. METHODS: A novel ultra-low-dose combination of Trametinib and Rapamycin, targeting IRF4 inhibition, was employed to investigate T cell proliferation, apoptosis, cytokine secretion, expression of T-cell dysfunction-associated molecules, effects of mitogen-activated protein kinase (MAPK) and mammalian target of rapamycin (mTOR) signaling pathways, and allograft survival in both in vitro and BALB/c to C57BL/6 mouse cardiac transplantation models. RESULTS: In vitro , blockade of IRF4 in T cells effectively inhibited T cell proliferation, increased apoptosis, and significantly upregulated the expression of programmed cell death protein 1 (PD-1), Helios, CD160, and cytotoxic T lymphocyte-associated antigen (CTLA-4), markers of T cell dysfunction. Furthermore, it suppressed the secretion of pro-inflammatory cytokines interferon (IFN)-γ and interleukin (IL)-17. Combining ultra-low-dose Trametinib (0.1 mg·kg -1 ·day -1 ) and Rapamycin (0.1 mg·kg -1 ·day -1 ) demonstrably extended graft survival, with 4 out of 5 mice exceeding 100 days post-transplantation. Moreover, analysis of grafts at day 7 confirmed sustained IFN regulatory factor 4 (IRF4) inhibition, enhanced PD-1 expression, and suppressed IFN-γ secretion, reinforcing the in vivo efficacy of this IRF4-targeting approach. The combination of Trametinib and Rapamycin synergistically inhibited the MAPK and mTOR signaling network, leading to a more pronounced suppression of IRF4 expression. CONCLUSIONS Targeting IRF4, a key regulator of T cell dysfunction, presents a promising avenue for inducing transplant immune tolerance. In this study, we demonstrate that a novel ultra-low-dose combination of Trametinib and Rapamycin synergistically suppresses the MAPK and mTOR signaling network, leading to profound IRF4 inhibition, promoting allograft acceptance, and offering a potential new therapeutic strategy for improved transplant outcomes. However, further research is necessary to elucidate the underlying pharmacological mechanisms and facilitate translation to clinical practice.
Animals ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Interferon Regulatory Factors/metabolism* ; Heart Transplantation/methods* ; T-Lymphocytes/immunology* ; Sirolimus/therapeutic use* ; Pyridones/therapeutic use* ; Graft Survival/drug effects* ; Pyrimidinones/therapeutic use* ; Cell Proliferation/drug effects* ; Apoptosis/drug effects* ; Male ; Signal Transduction/drug effects*

Objective:To investigate the current situation of nuclear medicine practices, determine the number of nuclear medicine staff, conduct internal exposure monitoring and dose estimation for nuclear mecidine staff engaged in 131I treatment in Zhejiang province. Methods:A survey was conducted over all the 22 hospitals involved in 131I treatment in the province. The 131I activity in thyroid of 96 stafff in 131I treatment workplaces were measured by means of direct method. At the same time, the effective doses from internal exposure were estimated and the influencing factors were analyzed. Results:131I activity in thyroids was found to be above the detection limit for 49 staff (51.04%) in nineteen hospitals. The maximum value of 131I activity was 629.18 Bq. There was no statistically significant difference in 131I detection rate in thyroid of 131I treatment staff between different positions, different genders and different levels of hospitals ( P>0.05). Comparisons of 131I activity of thyroid of nuclear medicine staff for theatment of thyroid cancers had shown that the highest was for nurses, followed by technicians and doctors, and the lowest was for cleaning staff ( H=6.39, P<0.05). The estimated committed effective dose to the nuclear medicine staff ranged from 0.05 to 2.37 mSv, with those below 1 mSv accounting for 93.88% of the total. Logistic regression analysis showed that nursing position was the risk factor contributing to the committed effective dose ( OR=2.805, 95% CI 1.076-7.314). Conclusions:In Zhejiang province, the committed effective dose to thyroid of nuclear medicine staff from 131I internal exposure was not in excess of the dose limit. However, the staff performing iodine therapy still need to strengthen protection against internal exposure and take scientific and effective protective measures to reduce the risk of health hazards from internal exposure.

Objective:To investigate the current situation of nuclear medicine practices, determine the number of nuclear medicine staff, conduct internal exposure monitoring and dose estimation for nuclear mecidine staff engaged in 131I treatment in Zhejiang province. Methods:A survey was conducted over all the 22 hospitals involved in 131I treatment in the province. The 131I activity in thyroid of 96 stafff in 131I treatment workplaces were measured by means of direct method. At the same time, the effective doses from internal exposure were estimated and the influencing factors were analyzed. Results:131I activity in thyroids was found to be above the detection limit for 49 staff (51.04%) in nineteen hospitals. The maximum value of 131I activity was 629.18 Bq. There was no statistically significant difference in 131I detection rate in thyroid of 131I treatment staff between different positions, different genders and different levels of hospitals ( P>0.05). Comparisons of 131I activity of thyroid of nuclear medicine staff for theatment of thyroid cancers had shown that the highest was for nurses, followed by technicians and doctors, and the lowest was for cleaning staff ( H=6.39, P<0.05). The estimated committed effective dose to the nuclear medicine staff ranged from 0.05 to 2.37 mSv, with those below 1 mSv accounting for 93.88% of the total. Logistic regression analysis showed that nursing position was the risk factor contributing to the committed effective dose ( OR=2.805, 95% CI 1.076-7.314). Conclusions:In Zhejiang province, the committed effective dose to thyroid of nuclear medicine staff from 131I internal exposure was not in excess of the dose limit. However, the staff performing iodine therapy still need to strengthen protection against internal exposure and take scientific and effective protective measures to reduce the risk of health hazards from internal exposure.

Background Excessive radon exposure is considered the second risk factor for lung cancer. Since the opening of the subway in a city of Zhejiang Province, the exposure level of radioactive gas radon in subway stations and its impact on occupational health have become one of the important issues of public concern. Objective To monitor the radon concentration of subways in a city in Zhejiang Province and explore the effect of radon exposure on chromosome aberration and micronuclei in the working population. Methods A total of 55 vehicle control rooms of 55 stations affiliated to two different subway lines in a city were measured for one year; the 110 ticket offices and 55 security checkpoints from the same 55 stations were measured from 16 March to 14 June. The radon concentrations were compared by job types, subway lines, and seasons referring to Measurement methods for determination of radon in environmental air (HJ 1212-2021). Peripheral blood lymphocyte chromosome aberration and micronucleus analyses were conducted in 165 subway workers from monitoring sites for three different job types, then the influencing factors were analyzed. The detection methods were adopted from the standards of Test and assessment of chromosomal aberrations on occupational health examinations for radiation workers (GBZ/T 248-2014) and Standard for the method of micronucleus detection in lymphocytes on occupational health examination for radiation workers and exposure dose estimation (GBZ/T 328-2023). Results The radon concentration range of the target subways in Zhejiang Province was 10-320 Bq·m⁻³, all lower than the national limit (≤400 Bq·m⁻³). The differences in radon radioactivity levels among different lines, job types, and time segments were statistically significant (P<0.05). The rates of chromosomal aberration and micronucleus formation among the 165 subjects were 0.224% and 0.024%, respectively. There were significant differences in the rates of chromosome aberration and micronuclei among different jobs (vehicle control room, ticket office, security checkpoint) (P<0.05), but the abnormal rates were lower than the limits of the corresponding national standard. No significant correlation was found between jobs and chromosomal aberrations or micronuclei (P>0.05). Chromosome aberration and micronuclei varied by age, subway station seniority, and smoking (P<0.05). No effect of the above factors on chromosome aberration and micronuclei was observed by logistic regression (P>0.05). Conclusion The radon concentration in the target subway system is at a normal level. The rates of chromosomal aberration and micronucleus formation vary by jobs, but both are lower than the corresponding national limits. Therefore, radon exposure has not yet caused outstanding health impact on the subway workers.

Objective To investigate the current situation of occupational health of radiation workers in Zhejiang Province, China, and to provide a theoretical basis for the improvement of standards and management systems for occupational health examinations of radiation workers. Methods Data of occupational health examination cases were collected from occupational health examination institutions, including basic information, type of physical examination (pre-job, on-job, off-job), and health examination results. The differences in occupational health examination results among different groups were analyzed, and the factors influencing occupational health of radiation workers were analyzed using a logistic regression model. Results A total of 5668 cases were collected, with 86% of the participants being male and 14% being female. Compared with the pre-job group, the on-job group showed an increased abnormal rate of triiodothyronine and the off-job group demonstrated an increased abnormal rate of leukocyte count (P < 0.05). Compared with the industrial group, the nuclear fuel group showed decreased abnormal rates of thyroid structure and thyroxine and an increased abnormal rate of triiodothyronine, and the medical group demonstrated an increased abnormal rate of thyroid structure (P < 0.05). The abnormal rates of thyroid structure and white blood cell count increased with the increase of working age (P < 0.05). The abnormal rates of white blood cell count, thyroid structure, triiodothyronine, and thyroid stimulating hormone were higher in female radiation workers than in male radiation workers (P < 0.05). Sex (female), radiation work history, and age were the risk factors affecting the occupational health of radiation workers (P < 0.05). Conclusion The occupational health status of radiological workers in Zhejiang Province needs to be further improved, and the occupational health management of radiological workers should be strengthened.

Objective To investigate the current situation of occupational health of radiation workers in Zhejiang Province, China, and to provide a theoretical basis for the improvement of standards and management systems for occupational health examinations of radiation workers. Methods Data of occupational health examination cases were collected from occupational health examination institutions, including basic information, type of physical examination (pre-job, on-job, off-job), and health examination results. The differences in occupational health examination results among different groups were analyzed, and the factors influencing occupational health of radiation workers were analyzed using a logistic regression model. Results A total of 5668 cases were collected, with 86% of the participants being male and 14% being female. Compared with the pre-job group, the on-job group showed an increased abnormal rate of triiodothyronine and the off-job group demonstrated an increased abnormal rate of leukocyte count (P < 0.05). Compared with the industrial group, the nuclear fuel group showed decreased abnormal rates of thyroid structure and thyroxine and an increased abnormal rate of triiodothyronine, and the medical group demonstrated an increased abnormal rate of thyroid structure (P < 0.05). The abnormal rates of thyroid structure and white blood cell count increased with the increase of working age (P < 0.05). The abnormal rates of white blood cell count, thyroid structure, triiodothyronine, and thyroid stimulating hormone were higher in female radiation workers than in male radiation workers (P < 0.05). Sex (female), radiation work history, and age were the risk factors affecting the occupational health of radiation workers (P < 0.05). Conclusion The occupational health status of radiological workers in Zhejiang Province needs to be further improved, and the occupational health management of radiological workers should be strengthened.

Objective To investigate the operation status and service level of radiation occupational health inspection institutions in Zhejiang Province, China, and to provide a basis for administrative departments and quality management departments to develop policies. Methods The investigation data of radiation occupational health inspection institutions in Zhejiang Province were collected for descriptive analysis of the regional distribution, nature, and service qualification of the institutions. Results There were 27 radiation occupational health inspection institutions in Zhejiang Province. These institutions were located in 11 cities, of which 85.18% were public institutions and 14.72% were private institutions. For the physical examination workload of radiation workers in Zhejiang Province in 2021, general hospitals accounted for 75.90%, private institutions accounted for 4.51%, and occupational prevention and treatment hospitals accounted for 19.59%. In the radiation occupational health inspection institutions, the stand-alone and online software installation rates were 33.33% and 37.04%, respectively. A total of 26 986 individuals (82.97%) underwent chromosome aberration examination. The examination rates of thyroid color Doppler ultrasound examination and eye lens examination were 41.24% and 82.97%, respectively. Pre-job, on-job, and off-job physical examination accounted for 25.81%, 70.52%, and 3.67%, respectively. For radiation workers who underwent on-job physical examination, diagnostic radiology workers accounted for the highest proportion of 34.90%. The excellent, qualified, and unqualified rates of 27 radiation occupational health inspection institutions were 7.41%, 88.89%, and 3.70%, respectively. Conclusion The network of radiation occupational health inspection institutions in Zhejiang Province is well-established and located mainly in general hospitals, occupational prevention and control institutions, and private institutions. To enhance the quality and proficiency of occupational health examinations, it is imperative to prioritize self-improvement and management, reinforce law enforcement supervision, actively engage in blind sample assessments, and advance the application of information technology and standardized services.

Objective: To investigate the health status of occupational mercury workers and reveal the effects of mercury exposure on the cardiovascular system. Methods: In June 2019, a total of 2651 mercury workers participated in the occupational health examination between 2016-2018 from a thermometer manufacturing plant and a fluorescent lamp manufacturing plant were included in this study. Then, they were divided into a high-level mercury exposure group (425 workers whose urine mercury concentration >35 μg/g creatinine) and a low-mercury mercury exposure group (2226 workers whose urinary mercury concentration <35 μg/g creatinine) . Mercury concentration in the workplace was also detected. Finally, the results of electrocardiogram (ECG) , blood routine, blood biochemistry and other physical examinations were analyzed. The measurement data of age and exposure years were analyzed by test. Urinary mercury and blood parameters were analyzed by Mann-Whitney nonparametric test. Chi-square test was used for the analyses of gender, ECG abnormality rate and other categorical data. Results: The 8-hour weighted average allowable concentration (CTWA) of mercury in the workplace of high-exposure group was 0.002 2-0.152 mg/m³. The abnormal rate of ECG in the high-exposed group (29.6%) was higher than that in the low-exposure group (10.1%) in 2018 (P<0.01) . Compared with the low-exposure group, the WBC of the high-exposure group from 2016 to 2018 was increased, with statistically significance (P<0.05) ; the RBC of the high-exposure group in 2016 and 2017 was decreased, with statistically significance (P<0.01) ; the total bilirubin concentration in the high-exposure group was decreased from 2016 to 2018, with statistically significance (P<0.05) . Conclusion Long-term exposure to high concentration of mercury in the workplace may influence cardiovascular system. Therefore, engineering protection and individual protection should be implemented well.

Objective: To investigate the association between the single nucleotide polymorphisms of rs12212067 in FOXO3 gene and the susceptibility to occupational noise-induced deafness in a Chinese Han population. Methods: A total of 1 066 cases of noise exposure workers from a large chemical fiber factory in Jiangsu Province were selected as the study subjects. All subjects’ basic data and field exposure data were collected through questionnaires and occupational health surveys. The subjects were divided into case group (531 persons, double ear high frequency average hearing threshold>25 dB) and control group (535 persons, double ear high frequency average hearing threshold≤25 dB) according to their results of pure tone hearing test .2ml fasting venous blood was collected for DNA extraction and genotyping was performed by TaqMan-PCR technique. Results: Genotyping results suggested that the GT+GG genotype is a risk factor for occupational noise-induced deafness, with an adjusted OR 95% confidence interval of 2.044 (1.51-2.78) . After the noise exposure intensity was stratified, the adjusted OR values and the 95% confidence intervals of noise intensity ≤85, 85-92 and>92 dB respectively 2.43 (1.52-3.90) , 2.17 (1.03-4.59) and 1.74 (1.07-2.83) . Conclusion GT-GG genotype in rs12212067 of FOXO3 gene may be a risk factor for occupational noise-induced deafness.