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 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 modified TROPIS surgery, incorporating both open and hanging stitches on the treatment of elevated anal fistula.Methods:For our study, 92 patients with high anal fistula, admitted between Jan. 2023 and Jun. 2024, were selected. They were divided into two categories: the observation group (45 modified TROPIS surgery) and the control group (47 cuts) ,to observe the clinical efficacy, postoperative recovery, quality of life and complications of the two groups.Results:Compared with the control group, the operation time, intraoperative blood loss and postoperative hospitalization time decreased in the observation group ( P<0.05) . Compared with the control group, the healing time of anal fistula in the observation group was (28.01±5.02) d, shorter than that in the control group (35.05±7.09) d, the healing rate was 97.78%, higher than that in the control group (80.85%) , and the recurrence rate was 4.44%, lower than that in the control group (19.14%) ( P<0.05) . The degree of postoperative pain and Wexner anal incontinence score in the observation group were lower than those in the control group ( P<0.05) . The life quality score of the observation group was higher than that of the control group ( P<0.05) . The complication rate of observation group was lower than that of control group ( P<0.05) . Conclusions:The modified TROPIS surgical method evidently provides advantages in anal fistula treatment. It can not only efficiently eliminate infections but also reduce anal movements and decrease the chances of post-surgical injuries and complications, presenting enhanced clinical options and suggesting a promising outlook for traditional anal fistula surgery.

Objective:To analyze the epidemiological characteristics and trends of preterm births in China using medical institution survey data, thereby providing epidemiological data support for perinatal care.Methods:Based on a nationwide sampling survey on healthcare quality data from 2017 to 2022, this study included 3 547, 4 436, 4 513, 4 535, 5 068, and 5 790 medical institutions, with 7 039 107, 8 926 441, 9 006 420, 7 051 984, 7 311 862, and 7 354 062 parturient women, respectively. The overall rates of preterm birth (live births at 28 to 36 +6 weeks of gestation/overall live births) and early preterm birth (live births at 28 to <34 weeks of gestation/overall live births) were calculated at the national level, across diverse provinces, autonomous regions, municipalities and Xinjiang Production and Construction Corps, and for various levels of medical institutions. Generalized estimating equations were used to analyze the influence of maternal characteristics and medical institution characteristics on the rates of preterm birth and early preterm birth. Results:From 2017 to 2022, both the preterm birth rate and the early preterm birth rate in China showed a continuous increase. The preterm birth rate rose from 5.13% (363 036/7 079 454) in 2017 to 6.56% (487 150/7 424 734) in 2022, and the early preterm birth rate increased from 1.32% (118 021/8 971 870) in 2018 to 1.43% (106 157/7 424 734) in 2022. These rates showed an overall increasing trend in private, secondary public specialty, and general hospitals. In tertiary public specialty hospitals, these rates fluctuated around 8.0% and 2.0% from the year 2018, respectively, while in tertiary public general hospitals, these rates peaked in 2020 at 8.63% (205 570/2 381 523) and 2.19% (52 197/2 381 523), respectively. Compared with 2017, by 2022, the preterm birth rate had increased to varying degrees in all provinces, autonomous regions, municipalities and Xinjiang Production and Construction Corps, except for Henan Province [preterm birth rate in 2017 was 6.22% (27 173/437 187); preterm birth rate in 2022 was 5.83% (37 604/645 104)]. As for the early preterm birth rate, it showed a decline in Fujian, Guangdong, Guangxi, Hainan, Henan, Jiangsu, Shanghai, Xinjiang, Yunnan, and Zhejiang, but had increased to varying degrees in all other provinces , autonomous regions, municipalities and Xinjiang Production and Construction Corps across the country. The grade and location of medical institutions both had a significant impact on the preterm birth rate and early preterm birth rate (both P<0.05). For every 1% increase in the proportions of multiparous women, women of advanced maternal age, or twin pregnancies, the preterm birth rate increased by 0.014%, 0.042%, and 0.763%, and the early preterm birth rate increased by 0.004%, 0.013%, and 0.239%, respectively (all P<0.05). Conclusion:From 2017 to 2022, the preterm birth rate and early preterm birth rate in China have continued to rise, reflecting the dual challenges of changing characteristics in the childbearing population and the uneven distribution of medical and health resources faced by maternal and child healthcare in China.

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 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 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 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.

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.