Objective To analyze the monitoring data of ¹³¹I internal exposure in Guangdong Province over the past 3 years, study the thyroid ¹³¹I contamination levels among nuclear medicine staff, and provide a basis for optimizing the monitoring plan. Methods Using a convenience sampling method, 574 detections of nuclear medicine staff from 28 hospitals in Guangdong Province were included in the study. The thyroid ¹³¹I activity was measured directly in vivo. Differences in detection rates were analyzed, and committed effective doses were estimated. Results Over the past 3 years in Guangdong Province, ¹³¹I accumulation was found in the thyroids of staff from 14 hospitals for 62 (10.8%) detections, with an average activity of 154.8 (13.2-8730.6) Bq. The adjusted annual intake was 50.7 (4.5-820.6) kBq. The committed effective dose was 0.56 (0.05-9.03) mSv/a, and the values were ≥ 2 mSv for 8 persons. Among different positions, nurses showed the highest detection rate (19.6%), followed by cleaners (14.7%), with significant differences (P<0.05). Among different exposure types, the detection rate was highest for loading medication into automatic dispenser (23.3%), and the mean activity was highest for entering thyroid cancer patient ward (495.4 Bq), with significant differences (P<0.05). Conclusion Monitoring of ¹³¹I internal exposure in Guangdong Province found that the radiation doses of some staff members had exceeded the threshold specified in other investigations. Routine personal ¹³¹I internal exposure monitoring should be conducted, with increased monitoring frequency. Priority should be given to nurses and cleaners, with monitoring extended to cleaners and outsourced dispensing staff.

Background In recent years, the increasingly widespread application of nuclear and medical radiation technologies has resulted in a large number of occupational populations exposed to low-dose ionizing radiation (LDIR). At present, there is no consistent conclusion on the effects of long-term exposure to LDIR on the metabolic health of the occupational population. Objective To explore the association between long-term exposure to LDIR and metabolic syndrome (MetS) among medical radiologists. Methods A cross-sectional study was conducted to enroll 6431 medical radiologists who ordered occupational health checkups from January 2022 to December 2023, and basic information such as demographic characteristics, occupational characteristics, lifestyles, and dietary habits was collected through questionnaires. Physical examinations were conducted using a standardized protocol. Individual dose equivalents of occupational external exposure were monitored by dosimeters worn by medical radiologists. Logistic regression model was used for identifying influencing factors of MetS and sensitivity analysis, and restricted cubic spline model was used to explore the dose-response relationship between cumulative effective dose and MetS. Two-stage linear regression was used to evaluate threshold effect of association between cumulative effective dose and MetS. Results The positive rate of MetS was 13.6% (877/6431) among the enrolled 6431 study participants. The logistic regression showed that gender, age, monthly income, body mass index (BMI), cumulative effective dose, and smoking were influencing factors for MetS. The risk of MetS was higher in males (OR=1.511, 95%CI: 1.209, 1.888); using the < 30 years old group as reference, the risk of MetS was higher in the 30-39 years old (OR=1.509, 95%CI: 1.095, 2.079), 40-49 years old (OR=2.214, 95%CI: 1.551, 3.161), and ≥50 years old (OR=3.480, 95%CI: 2.338, 5.181) groups; using the <10000 yuan group as reference, the risk of MetS was lower in the group with a monthly income of 10000-14999 yuan (OR=0.715, 95%CI: 0.582, 0.878); the risk of MetS was higher in the BMI ≥ 24 kg·m⁻² group (OR=7.548, 95%CI: 6.223, 9.156); using the < 0.76 mSv group as reference, the risk of MetS was higher in the cumulative effective dose of 0.76-2.73 mSv group (OR=1.270, 95%CI: 1.017, 1.586); the risk of MetS was higher in the smoking group (OR=1.734, 95%CI: 1.428, 2.107). The results of restricted cubic spline showed that the cumulative effective dose was nonlinearly correlated with MetS (P _{non-linearity}=0.028), with an inflection point of 1.25 mSv. The risk of developing MetS increased by 34.1% for each unit increase in cumulative effective dose up to 1.25 mSv, whereas above 1.25 mSv, the statistical association was not significant. The sensitivity analysis results showed that after excluding the self-reported hypertensive and diabetic patients, the cumulative effective dose 0.76-2.73 mSv group still had an increased risk of developing MetS compared with the < 0.76 mSv group (P < 0.05), and the results were robust. Conclusion Among medical radiologists, male, age, BMI, and smoking are positively correlated with MetS, and monthly income is negatively correlated with MetS; cumulative effective dose is non-linearly correlated with MetS among medical radiologists.

Objective To investigate the induction of senescence in L02 hepatocytes by low-dose fractionated X-ray radiation and its effects on oxidative stress, oxidative damage, and nuclear factor-κB (NF-κB) pathway protein levels. Methods L02 cells were subjected to fractionated X-ray irradiation at doses of 0.1, 0.2, and 0.5 Gy per fraction for a total of six fractions. Assays were performed 24 hours after the final irradiation. Measurements included SA-β-gal staining, the mRNAs of senescence-related genes p53 and p21 and their encoded proteins, mRNAs of genes encoding senescence-associated secretory phenotype factors (IL-6, IL-8, GM-CSF, MMP-15), reactive oxygen species, oxidative and anti-oxidative markers (malondialdehyde, glutathione, superoxide dismutase), DNA oxidative damage markers (8-OHdG and γ-H2AX), and NF-κB pathway protein levels. Results Compared with the control group, at 24 hours after the end of six irradiations, the number of cells positive in SA-β-gal staining was significantly increased in all dose groups. The mRNA and protein levels of p21 and p53 were significantly elevated in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The mRNA levels of genes encoding IL-6, GM-CSF, and MMP-15 were significantly increased in all dose groups (P < 0.05). The mRNA levels of the gene encoding IL-8 were significantly increased in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The levels of reactive oxygen species, malondialdehyde, and glutathione were significantly increased in all dose groups (P < 0.01). The level of superoxide dismutase was significantly increased in the 0.5 Gy × 6 group (P < 0.01). The levels of 8-OHdG were significantly increased in all dose groups (P < 0.05). In both the 0.2 Gy × 6 and 0.5 Gy × 6 groups, the expression levels of γ-H2AX and p-NF-κB p65 were significantly increased (P < 0.05), and the levels of IκBα were significantly decreased (P < 0.05). Conclusion Low-dose fractionated X-ray radiation can induce senescence and cause alterations in oxidative stress, oxidative damage, and the levels of NF-κB pathway proteins in L02 hepatocytes.

Objective:To study and analyze radiation doses to the eye of the lens dose in interventional radiology staff of Guandong medical institutions from 2019 to 2023.Methods:Employing a convenience sampling method, the lens dose and chest dose was monitored with TLD dosimeters in 34 level A tertiary medical institutions. The monitoring data were analyzed on the basis of a summary, and the relationship between the two was explored.Results:A total of 1 033 interventional radiology staff were monitored. The ocular lens doses were in the range of (

Objective:To investigate the inflammatory indicator levels and influencing factors on middle-aged and elderly male residents at different residential distances from a uranium mine in Guangdong, so as to provide scientific data for the health risk assessment of the residents therein.Methods:With stratified sampling method, two groups of the permanent middle-aged and elderly male residents were randomly sampled within < 10 km and 10-20 km of the uranium mine, along with the basic demographic characteristics and lifestyle information collected through face-to-face questionnaire survey. Both height and weight of the respondents were measured using standard method and their body mass indexes (BMI) were calculated. Through collection of the venous blood, the levels of a wide range of inflammatory indicators were measured, such as C-reactive protein (CRP), complement C3, complement C4, leukocytes, lymphocytes, neutrophils, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and others. Multiple linear regression was used to analyze the influencing factors on the levels of inflammation indicators.Results:A total of 867 middle-aged and elderly male residents were included in this study, including one group of 431 residents within the 10-20 km at an average age of 51.54±5.37, and a second group of 436 residents within <10 km at an average age of 52.05±5.24. The result of multiple linear regression showed a positive correlation of the distance groups with complement C4 level ( β=0.014, 95% CI: 0.001-0.027) and lymphocyte number ( β=0.086, 95% CI: 0.003-0.168) ( t=2.07, 2.04, P<0.05). The ages of middle-aged and elderly male residents around the uranium mine was positively correlated ( t=2.50, P<0.05) with the levels of complement C4 ( β=0.018, 95% CI: 0.004-0.031), and negatively correlated ( t=-3.25, -2.97, P<0.05) with the levels of TNF-α ( β=-63.022, 95% CI: -101.114 to -24.929) and IL-6 ( β=-14.694, 95% CI: -24.396 to -4.992). Smoking was positively correlated ( t=4.29, 4.81, 3.19, P<0.05) with leukocytes number ( β=0.630, 95% CI: 0.341-0.918), lymphocytes number ( β=0.226, 95% CI: 0.134-0.319) and neutrophils number ( β=0.372, 95% CI: 0.143-0.601), and negatively correlated ( t=-2.07, -1.98, P<0.05) with the levels of TNF-α ( β=-43.551, 95% CI: -84.778 to -2.324) and IL-6 ( β=-10.603, 95% CI: -21.103 to -0.102). BMI was positively correlated ( t=8.60, 3.62, 3.18, 4.01, 2.10, P<0.05) with complement C3 level ( β=0.108, 95% CI: 0.084-0.133), complement C4 level ( β=0.026, 95% CI: 0.012-0.039), leukocytes number ( β=0.433, 95% CI: 0.166-0.699), lymphocyte number ( β=0.175, 95% CI: 0.089-0.261), and neutrophil number ( β=0.226, 95% CI: 0.014-0.438). Fruit consumption ( β=0.017, 95% CI: 0.001-0.034) was positively correlated with complement C4 levels ( t=2.10, P<0.05). Conclusions:This study showed no significant correlation between the inflammatory index levels of middle-aged and elderly male residents around the uranium mine and uranium mining. Age, smoking, BMI and fruit consumption were the influencing factors on the levels of inflammatory indicators of middle-aged and elderly male residents.

Objective:To investigate differential gene expression, enriched biological processes, and pathway differences between residents of a high-background radiation area (HBRA), Yangjiang, and a control area—Enping.Methods:Seven residents were selected from the HBRA (the HBRA group) and seven from the control area (the control group) using the two-stage random sampling method. The cumulative radiation dose for each individual was calculated based on the ambient gamma exposure levels. Peripheral blood samples were collected and analyzed via high-throughput sequencing to identify differentially expressed genes. Subsequent analyses included gene ontology (GO) for biological process (BP), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and gene set enrichment analysis (GSEA).Results:The median ages of the HBRA and control groups had no statistically significant difference ( P = 0.370). The cumulative external doses for the HBRA and control groups were (99.59±20.07) and (33.82±10.61) mSv, respectively. This difference was statistically significant ( t = -5.88, P = 0.001). High-throughput sequencing identified 1 224 differentially expressed genes in the HBRA group, including 32 senescence-related genes, compared to the control group. The result of GO-BP analysis showed that these genes were predominantly enriched in cell signaling, biosynthesis, localization, cell cycle regulation, and cellular stress responses. KEGG analysis revealed significant enrichment in the chemokine and MAPK signaling pathways, as well as in pathways related to the cell cycle, autophagy, and mitophagy. Furthermore, GSEA analysis confirmed that the differentially expressed genes were mainly related to cell cycle regulation and mitochondrial functions. Conclusions:Differentially expressed mRNAs are found in the peripheral blood of residents in the HBRA. These mRNAs are predominantly associated with key biological processes and pathways, including cell cycle regulation, chemokine and MAPK signaling pathways, and mitophagy.

Objective To investigate the role of the O-6-methylguanine-DNA methyltransferase (MGMT) gene-3′ untranslated region (UTR) microRNA-associated single nucleotide polymorphism (miRSNP) (rs7896488 G>A) in affecting miR-4297-targeted modulation of MGMT in senescence of lung cells with polymorphic genotypes induced by fractionated low dose ionizing radiation (LDIR). Methods i) MiRSNPs were predicted and screened using bioinformatics, and DNA from two types of lung cells, A549 cells and human bronchial epithelioid cells (HBE cells), was extracted for target gene sequencing. After co-transfection of pGL3c-MGMT-3′UTR-rs7896488 G>A reporter gene recombinant plasmid, pRL-TK Vector with micrON mimic NC #22 or micrON hsa-miR-4297 mimic (set up as the mimic NC group and the miR-4297 mimic group) in these two types of lung cells, dual luciferase reporter gene assay was performed. The relative expression of MGMT mRNA was detected by real-time fluorescence quantitative polymerase chain reaction, and the relative expression of MGMT protein was detected by Western blotting. ii) These two types of lung cells were randomly divided into the control group and irradiation group, which received either 0 or 100 mGy X-rays irradiation seven times. After irradiation, the cells were transfected with either micrON mimic NC #22 or micrON hsa-miR-4297 mimic, resulting in mimic NC + control group, miR-4297 mimic + control group, mimic NC + irradiation group, and miR-4297 mimic + irradiation group. Cells were collected for senescence-associated-β-galactosidase (SA-β-Gal) staining, and the relative expression of matrix metalloproteinase-9 (MMP-9) and chemokine (C-X-C motif) ligand-1 (CXCL-1) proteins was detected via Western blotting. Results i) The rs7896488 G>A was the miRSNP located in the conserved binding region targeted by miR-4297 in the MGMT gene 3′UTR. A549 cells were the rs7896488 GG wild-type homozygous genotype, while HBE cells were the rs7896488 GA heterozygous mutant genotype. In the miR-4297 mimic group, A549 and HBE cells carrying the rs7896488 G allele showed significantly lower dual-luciferase activity compared with that in the mimic NC group (both P<0.01). However, there was no significant difference in dual-luciferase activity between the two groups in both A549 and HBE cells carrying the rs7896488 A allele (both P>0.05). The relative expression levels of MGMT mRNA and MGMT protein of A549 cells in the miR-4297 mimic group were lower than those in the mimic NC group (both P<0.05). However, there was no significant difference in MGMT mRNA and MGMT protein of HBE cells between these two groups (both P>0.05). ii) The relative activity of SA-β-Gal and the relative expression of MMP-9 and CXCL-1 proteins of A549 cells in the miR-4297 mimic+irradiation group were higher than those in the mimic NC + control group, the miR-4297 mimic + control group, and the mimic NC + irradiation group (all P<0.05). The relative activity of SA-β-Gal and the relative expression of MMP-9 and CXCL-1 proteins of HBE cells in the miR-4297 mimic + irradiation group were higher than those in the mimic NC + control group and the miR-4297 mimic + control group (all P<0.05), while there was no significant difference compared with those in the mimic NC + irradiation group (all P>0.05). Conclusion MGMT-3′UTR-miRSNP rs7896488 G>A plays a role in LDIR-induced senescence of lung cells with different polymorphic genotypes by affecting miR-4297-targeted regulation of MGMT.

Objective To understand the situation of dental cone beam computed tomography (CBCT) quality control testing phantoms in radiation health technical service institutions in Guangdong province, analyze the differences among different phantoms, and provide a reference for dental CBCT quality control testing. Methods The testing phantoms of 49 radiation health technical service institutions were used as the research objects. The designated CBCT equipment was used for scanning and imaging. The Z-score method was used to evaluate the high-contrast resolution, low-contrast resolution, and distance measurement deviation of each phantom. Results The satisfaction rates of various items for the phantoms in 49 institutions ranged from 85.7% to 100%. The distance measurement deviations of four institutions were “suspicious”, and the high-contrast resolution of four institutions and the distance measurement deviation of one institution were “unsatisfactory”. Conclusion The overall performance of dental CBCT quality control testing phantoms in radiological health technical service institutions in Guangdong province is satisfactory. However, there are still some phantoms with poor results in items such as distance measurement deviation and high-contrast resolution. The structural design, material selection, and manufacturing process of the phantom may all affect the results of quality control testing. Therefore, appropriate phantoms, optimized exposure conditions, and suitable reconstruction algorithms should be used in CBCT quality control testing to ensure accurate and reliable measurements.

Objective To investigate the effects of fractionated low-dose ionizing radiation (LDIR) on the ferroptosis in human bronchial epithelial (HBE) cells as well as the associated differentially expressed genes (DEGs), biological processes, and signaling pathways. Methods HBE cells were exposed to different single doses of X-ray irradiation (0, 25, 50, 75, and 100 mGy) for 24, 48, and 72 h, respectively. The change in cell viability was detected by MTT assay. Cells were irradiated with 0, 25, 50, and 100 mGy X-rays 5 times, with 48 h between each irradiation and a dose rate of 50 mGy/min. Cells were harvested 24 h after irradiation for the measurement of the expression of ferroptosis-related genes SLC7A11 and GPX4 at the mRNA and protein levels, cellular iron content, and the expression of FTH1 and FTL mRNAs. High-throughput sequencing was used to screen for the DEGs in each dose group, followed by Gene Ontology-Biological Process (GO-BP) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Set Enrichment Analysis (GSEA). Results Compared with the control group, single-dose LDIR significantly increased cell proliferation at 75 mGy after 24 h (P < 0.05), at 50, 75, and 100 mGy after 48 h (P < 0.05), and at 75 and 100 mGy after 72 h (P < 0.05). Compared with the control group, at the end of the fifth fractionated LDIR, SLC7A11 and GPX4 mRNAs decreased at all doses (P < 0.05), SLC7A11 protein decreased at all doses, GPX4 protein decreased at 25 and 100 mGy, iron content increased at all doses, and FTH1 and FTL mRNAs decreased at all doses (P< 0.05). Sequencing analysis identified 248, 30, and 291 DEGs and 10, 2, and 9 ferroptosis-associated genes at the three doses compared to the control. Gene Ontology-Biological Process analysis showed that DEGs were mainly enriched in biological processes such as response to lipids, cell death, and response to unfolded proteins. Kyoto Encyclopedia of Genes and Genomes analysis showed that DEGs were mainly enriched in the JAK-STAT signaling pathway, lipids and atherosclerosis, ferroptosis, protein processing in the endoplasmic reticulum, and FoxO signaling pathway. Gene set enrichment analysis showed that DEGs were mainly enriched in ferroptosis, fatty acid degradation, and glutathione metabolism. Conclusion Fractionated low-dose radiation induced ferroptosis in HBE cells, and DEGs were predominantly enriched in biological processes and signaling pathways related to inflammation, ferroptosis, and endoplasmic reticulum stress.

Objective:To study and analyze radiation doses to the eye of the lens dose in interventional radiology staff of Guandong medical institutions from 2019 to 2023.Methods:Employing a convenience sampling method, the lens dose and chest dose was monitored with TLD dosimeters in 34 level A tertiary medical institutions. The monitoring data were analyzed on the basis of a summary, and the relationship between the two was explored.Results:A total of 1 033 interventional radiology staff were monitored. The ocular lens doses were in the range of (