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 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.

In recent years, the bacteriophage Φ29 (Phi29) DNA polymerase has garnered increasing attention due to its high-fidelity amplification capacity at constant temperatures. To advance the industrial application of this type of isothermal polymerases, this study mined and characterized new enzymes from the microbial metagenome based on the known Phi29 DNA polymerase sequence. The results revealed that a new enzyme, Php29 DNA polymerase, was identified in the microbial metagenome with plants as the hosts. This enzyme exhibited higher strand displacement activity, with a 59.5% similarity to bacteriophage Φ29. Experimental validation demonstrated that the enzyme had 3'→5' exonuclease activity, and its amplification products can serve as substrates for further catalytic reactions. The discovery and validation of Php29 DNA polymerase gives insights into the future industrial application of isothermal polymerases.
DNA-Directed DNA Polymerase/metabolism* ; Bacillus Phages/genetics* ; Metagenome

Bacterial therapy has attracted increasing attention due to its special mechanism and abundant applications. With the flourishing development of synthetic biology, therapeutic genes have been introduced into engineering bacteria to improve their antitumor efficacy. However, it is difficult to spatiotemporally control the expression of these therapeutic genes at the tumor site in vivo, thereby considerably limiting the application of engineered bacteria in tumor treatment. To resolve this problem, we constructed a temperature-responsive bacterial strain capable of triggering the expression of exogenous genes in a laser-controllable way. Noxa, a pro-apoptotic protein, is chosen to test the expression of exogenous protein and its anti-tumor effect in engineered bacteria upon laser irradiation. Firstly, Noxa was fused to the C-terminus of the bacterial outer membrane protein cytolysin A (ClyA), and then the recombinant gene fragment ClyA-Noxa was inserted into the temperature-sensitive plasmid pBV220 and the recombinant plasmid was transformed into non-pathogenic Escherichia coli MG1655. Thus, we constructed the engineering strain (TRB@Noxa) that could express Noxa on the bacterial surface. TRB@Noxa could target and colonize the tumor tissue without causing notable host toxicity. The bacterial infection triggered thrombosis in the tumor tissue, resulting in the darkness of tumor sites. In a xenograft mouse tumor model, our strategy demonstrated precise tumor targeting and strong tumor inhibition. In conclusion, we successfully constructed a new engineering bacterial strain TRB@Noxa. TRB@Noxa combined with photothermal therapy could arrest tumor growth in the absence of photosensitizers, which represents an appealing method for antitumor therapy in the future.
Escherichia coli/radiation effects* ; Animals ; Humans ; Lasers ; Mice ; Proto-Oncogene Proteins c-bcl-2/biosynthesis* ; Neoplasms/therapy* ; Genetic Engineering ; Cell Line, Tumor ; Escherichia coli Proteins/genetics*

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 Analyze the nasal nitric oxide(NNO)of CRS children,and explore the clinical value of NNO in the diagnosis and treatment of CRS in children.METHODS CRS children diagnosed in the outpatient clinic were selected,and were divided into CRS with and without AR according to their allergen results.VAS score and NNO test were performed for them.Healthy children during the same period were selected as the control group.Finally their results were compared and analyzed.RESULTS The NNO of CRS children with and without AR were(193±62)ppb and(138±49)ppb,both lower than the control group's[(243±51)ppb];There were negative correlations between NNO and VAS scores in CRS children without AR before and after treatment;The NNO of CRS children with and without AR were significantly increased after treatment(P<0.05);NNO has high predictive value for diagnosing CRS children without AR(P<0.01).CONCLUSION The levels of NNO in different types of CRS were lower than normal,and CRS children without AR was lower than those with AR.NNO could assist in the diagnosis of CRS,dynamically reflect the severity of nasal inflammation,and help to distinguish the allergic status of CRS.

Objective:To investigate associations of serum nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), apoptosis-associated speck like protein containing a caspase recruitment domain (ASC), caspase-1 with the outcome in patients with hypertensive intracerebral hemorrhage (HICH) after minimally invasive neuroendoscopic surgery.Methods:Patients with HICH underwent minimally invasive neuroendoscopic surgery at the Affiliated Hospital of Noncommissioned Officer School, Army Medical University between June 2022 and June 2024 were included prospectively. According to the Glasgow Outcome Scale score at 3 months after surgery, the patients were divided into a good outcome group (4-5) and a poor outcome group (1-3). The clinical data and peripheral blood levels of NLRP3, ASC, caspase-1, interleukin (IL)-18, and IL-1β between the two groups were compared. Multivariate logistic regression analysis was used to determine assocations of serum NLRP3, ASC, caspase-1 with the postoperative outcome. Results:A total of 121 patients with HICH were enrolled, including 71 males (58.68), aged 56.11±4.96 years. At 3 months after surgery, 70 patients (57.9%) had good outcome, 51 (42.1%) had poor outcome, and 3 died. Onset to admission time, onset to first CT scan time, onset to surgery time, baseline serum NLRP3, ASC, caspase-1, baseline hematoma volume, and the proportion of patients with hematoma rupture into the ventricles and midline shift in the poor outcome group were significantly higher than those in the good outcome group, while baseline Glasgow Coma Scale (GCS) score and hematoma clearance rate were significantly lower than those in the good outcome group ( P<0.05). Multivariate logistic regression analysis showed that after adjusting for other factors such as onset to surgery time, baseline GCS score, hematoma rupture into the ventricles, and hematoma clearance rate, baseline serum NLRP3 (odds ratio [ OR] 2.018, 95% confidence interval [ CI] 1.502-2.711; P<0.001), ASC [ OR 1.764, 95% CI 1.418-2.195; P<0.001], caspase-1 [ OR 1.901, 95% CI 1.476-2.449; P<0.001]) were significantly independently associated with the poor outcome. Conclusion:The serum levels of NLRP3, ASC, and caspase-1 are significantly higher in HICH patients with poor outcome, and are independently associated with the poor outcome after minimally invasive neuroendoscopic surgery.

Objective:To investigate the predictive value of D-dimer (DD)/platelet count (PLT) ratio (DPR) and fibrinogen (Fg)/C-reactive protein (CRP) ratio for lower extremity deep venous thrombosis (LEDVT) in patients with spontaneous intracerebral hemorrhage (ICH).Methods:Consecutive patients with ICH admitted to the Department of Neurosurgery, the Affiliated Hospital of Noncommissioned Officer School, Army Medical University from February 2023 to November 2024 were included retrospectively. The baseline clinical data and laboratory test results between the LEDVT group and the non-LEDVT group were compared. Multivariate logistic regression analysis was used to evaluate the independent influencing factors of LEDVT. Receiver operating characteristic (ROC) curves were used to evaluate the predictive efficacy of influencing factors for patients with ICH complicated with LEDVT. Results:A total of 156 patients with ICH were enrolled, including 67 males (42.9%), aged 61.54±7.91 years; 47 patients (30.1%) experienced LEDVT during hospitalization. Univariate analysis showed that DD, PLT, DPR, Fg, and CRP in the LEDVT group were significantly higher than those in the non-LEDVT group, while the Fg/CRP ratio was significantly lower than that in the non-LEDVT group (all P<0.05). Multivariate logistic regression analysis showed that DD (odds ratio [ OR] 5.499, 95% confidence interval [ CI] 2.909-10.395; P<0.001), PLT ( OR 1.044, 95% CI 1.026-1.062; P<0.001), Fg ( OR 2.119, 95% CI 1.482-3.031; P<0.001), DPR ( OR 5.924, 95% CI 3.058-11.475; P<0.001), and Fg/CRP ratio ( OR 0.614, 95% CI 0.505-0.746; P<0.001) were the independent influencing factor for the occurrence of LEDVT in patients with ICH. ROC curve analysis showed that the areas under the curves of DD, PLT, Fg, DPR and the Fg/CRP ratio for predicting LEDVT in patients with ICH were 0.784 (95% CI 0.711-0.846), 0.772 (95% CI 0.699-0.836), 0.711 (95% CI 0.633-0.781), 0.782 (95% CI 0.709-0.844), and 0.778 (95% CI 0.705-0.841), respectively. The area under the curve for the combined prediction of DD+PLT+Fg was 0.878 (95% CI 0.816-0.924), and the area under the curve for the combined prediction of DPR+Fg/CRP ratio was 0.921 (95% CI 0.867-0.958). The latter showed a higher predictive value. Conclusion:The combined detection of DPR and Fg/CRP ratio has higher predictive value for LEDVT in patients with ICH.

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.