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.

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 understand the drug resistance genes,virulence genes and molecular epidemiological characteristics of extensively drug-resistant hypervirulent Klebsiella pneumoniae(XDR-hvKP)strains causing hospital-associated infection.METHODS The clinical isolates of XDR-hvKP were collected from Tongling People's Hospital from Jul.2020 to Dec.2022.The strains were identified by matrix-assisted laser desorption ionization-time-of-flight(MALDI-TOF)mass spectrometry,the common drug resistance genes and virulence genes were an-alyzed by Sanger sequencing,the capsular serotypes were determined by wzi gene sequencing;the drug resistance genes,virulence genes and ST subtypes were observed by means of whole-genome sequencing(WGS)technique.RESULTS Totally 18 strains of XDR-hvKP were collected,55.56％(10/18)of which were isolated from blood specimens,and 61.11％(11/18)were isolated from critical care medicine department.Sanger sequen-cing analysis showed that all of the strains carried blaKPC-2 drug resistance gene;rmpA2(100.00％)and rmpA,i-roN,iutA(94.44％,17/18)were the major virulence genes carried by the strains.WGS analysis indicated that all of the 18 XDR-hvKP isolates carried multiple drug resistance genes such as blaKPC-2 carbapenemase and the viru-lence genes like capsule(rmpA/rmpA2),aerobacterin(iucABCD-iutA),Salmonella(iroN)and yersinin(ybt).All of the ST subtypes were ST 11,and all of the capsular serotypes were KL 64.CONCLUSIONS The ST11-KL64 type XDR-hvKP strains carry blaKPC-2;rmpA,rmpA2,iroN and iutA are the major virulence genes.It is necessary to strengthen the monitoring of key population of the key departments and make joint efforts of multiple departments to contain the transmission of the strains.

Objective To investigate the role of poly(rC)-binding protein 1(PCBP1)in cadmium(Cd)-induced ferroptosis in mouse neuroblastoma Neuro-2a(N2A)cells.Methods N2A cells were exposed to a concentration gradient of CdCl?(0,1,2,4 μmol/L)for 72 h.Cell viability was assessed by trypan blue staining.Western blotting was employed to detect the expression of ferroptosis-related proteins(GPX4,HMOX1,ACSL4)and PCBP1.Intracellular Fe2? level and lipid peroxidation were detected using FerroOrange and BODIPY581/591 C11 probes,respectively.Ferrostatin-1(Fer-1),a ferroptosis inhibitor,was applied to confirm the critical role of ferroptosis in Cd-induced cytotoxicity.Molecular docking was performed to elucidate the interaction between PCBP1 and ferritin,as well as the binding sites of Cd2?.PCBP1 overexpression plasmid was further constructed for functional validation.Results Cd exposure suppressed cell viability in N2A cells in a dose-dependent manner(P<0.01),significantly down-regulated GPX4 expression(P<0.05),up-regulated HMOX1 expression(P<0.01),and induced Fe2? overload and lipid peroxidation(P<0.01).Molecular docking revealed that Cd2? directly bound to the KH2 domain of PCBP1 and then co-localized on the outer surface of ferritin heavy chain.Overexpression of PCBP1 markedly reversed Cd-induced Fe2? accumulation,GPX4 down-regulation,lipid peroxidation,and cell death.Conclusion Cd exposure disrupts PCBP1-mediated iron homeostasis via transcriptional suppression and competitive displacement of metal ions,and then synergistically drives Fe2? overload-triggered ferroptosis cascades,ultimately leading to neurotoxicity.Targeting PCBP1-mediated iron homeostasis can effectively mitigate Cd-induced neurotoxicity,and may serve as a novel therapeutic strategy.

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 relationships of serum procalcitonin(PCT),α1-acid glycoprotein(α1-AGP)and cluster of differentiation 64(CD64)index with the severity of illness and prognosis in patients with pulmonary Candida infection after lung cancer surgery.Methods A pro-spective study was conducted in 120 patients with pulmonary Candida infection after lung cancer sur-gery as infection group,and 60 patients without infection after lung cancer surgery in the same period were selected as control group.Baseline characteristics and laboratory indicators were compared be-tween the two groups.Differences in serum PCT,α1-AGP,CD64 index in peripheral blood,and plasma 1,3-β-D glucan test(BG)were compared among patients with different severities of illness and prognoses in the infection group.The relationship between serum indicators and prognosis as well as their predictive efficiencies were analyzed,and external validation was performed.Results The levels of serum PCT,α1-AGP,CD64 index in peripheral blood,and plasma BG in the infection group were significantly higher than those in the control group(P＜0.05).In the infection group,the levels of serum PCT,α1-AGP,and CD64 gradually decreased significantly in patients with severe,moderate,and mild illness,and the levels of these indicators in dead patients were significantly higher than those in surviving patients(P＜0.05).Survival curve analysis showed that patients with low levels of serum PCT,α1-AGP,and CD64 index before treatment had higher survival rates than those with high levels of these indicators.Receiver operating characteristic(ROC)curve analysis revealed that the combined prediction of PCT,α1-AGP,and CD64 index for mortality was superior to individual indicators or their pairwise combinations,and external validation confirmed the good predictive efficacy of the combined prediction.Conclusion PCT,α1-AGP,and CD64 index are closely related to pulmonary Candida infection after lung cancer surgery,and the combined detection of these indicators has certain predictive value for 28-day prognosis.

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 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.