Background Exposure to benzo[a]pyrene (BaP) may impair lung function through various mechanisms; however, it remains uncertain whether BaP induces ferroptosis in lung tissue cells, resulting in lung function impairment. Objective To investigate the ferroptosis of lung tissue cells triggered by subchronic BaP exposure in mice and its correlation with lung injury, and to explore the function of ferroptosis in BaP-induced lung tissue damage. Method Seventy-two healthy 3-weeks-old male C57BL/6J mice were acclimatized for 1 week and then randomly divided into six groups: control group (corn oil 10 mL·kg⁻¹), low-dose BaP group (2.5 mg·kg⁻¹), medium-dose BaP group (5 mg·kg⁻¹), high-dose BaP group (10 mg·kg⁻¹), BaP+ferrostatin-1 (Fer-1) group (10 mg·kg⁻¹+1 mg·kg⁻¹), and Fer-1 group (1 mg·kg⁻¹), with 12 mice each group. Corn oil and BaP were administered via gavage every other day, followed by an intraperitoneal injection of Fer-1 the subsequent day, throughout a period of 90 d. Whole-body plethysmography was applied to detect lung function; hematoxylin-eosin staining (HE) and Masson staining were used to observe lung tissue injury and fibrosis; microscopy of alveolar epithelial cells was conducted to reveal mitochondrial morphology; biochemical assays were used to measure the content of tissue iron, malondialdehyde (MDA), and glutathione (GSH), as well as the activity of glutathione peroxidase (GSH-Px); Western blotting and real-time quantitative PCR (RT-qPCR) analyses were performed to reveal the protein and mRNA expression of ferroptosis markers. Results Compared to the control group, the high-dose BaP group showed a significant increase in expiration time (Te) (P<0.01), and a significant decrease in ratio rate of achieving peak expiratory flow (Rpef), tidal volume (TVb), peak inspiratory flow (PIF), minute volume (MVb), and peak expiratory flow (PEF) (P<0.05 or 0.01). Based on the results of HE and Masson staining, partial destruction of alveolar structures, thickening of alveolar walls, infiltration of inflammatory cells, significant thickening of tracheal walls and a large deposition of collagen fibers in lung tissue were observed in the medium- and high-dose BaP groups. By microscopy, the alveolar epithelial cells exposed to low-dose BaP showed condensed chromatin, and the mitochondria exposed to medium and high-dose BaP showed wrinkles, increased mitochondrial membrane density, and diminished mitochondrial cristae. Compared to the control group, in the medium- and high-dose BaP groups, the lung tissue iron content and the expression levels of ACSL4 protein and mRNA significantly elevated (P<0.01 or 0.05), while the mRNA expression level of SLC7A11 significantly decreased (P<0.05); in the high-dose BaP group, the MDA content, COX2 protein, and PTGS2 mRNA expression levels significantly increased (P<0.05 or 0.01), GSH content and GSH-Px activity, GPX4 protein and mRNA expression levels, and the expression level of SLC7A11 protein significantly decreased (P<0.01 or 0.05). The ferroptosis inhibitor Fer-1 markedly reversed respiratory function, morphology, mitochondrial alterations, and the aforementioned ferroptosis-related biochemical indicators. Conclusion Subchronic exposure to BaP can induce ferroptosis in mice lung tissue cells, resulting in compromised lung function.

Background The active metabolite of benzo[a]pyrene (BaP), 7,8-dihydroxy-9,10-epoxybenzo[a]pyrene (BPDE), can form adducts with DNA, but the spectrum of BPDE-DNA adducts is unclear. Objective To identify the distribution of BPDE adduct sites and associated genes at the whole-genome level by chromatin immunoprecipitation followed by sequencing (ChIP-Seq), and serve as a basis for further exploring the toxicological mechanisms of BaP. Methods Human bronchial epithelial-like cells (16HBE) were cultured to the fourth generation inthe logarithmic growth phase. Cells were harvested and added to chromatin immunoprecipitation lysis buffer. The lysate was divided into experimental and control groups. The experimental group received a final concentration of 20 μmol·L⁻¹ BPDE solution, while the control group received an equivalent volume of dimethyl sulfoxide solution. The cells were then incubated at 37 °C for 24 h. Chromatin fragments of 100-500 bp were obtained through sonication. BPDE-specific antibody (anti-BPDE 8E11) was used to enrich DNA fragments with BPDE adducts. High-throughput sequencing was conducted to detect BPDE adduct sites. The top 1000 peak sequences were subjected to motif analysis using MEME and DREME software. BPDE adduct target genes at the whole-genome level were annotated, and Gene Ontology (GO) functional analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of BPDE adduct target genes were conducted using bioinformatics techniques. Results The high-throughput sequencing detected a total of 842 BPDE binding sites, distributed across various chromosomes. BPDE covalently bound to both coding and non-coding regions of genes, with 73.9% binding sites located in intergenic regions, 19.6% in intronic regions, and smaller proportions in upstream 2 kilobase, exonic, downstream 2 kilobase, and 5' untranslated regions. Regarding the top 1000 peak sequences, four reliable motifs were identified, revealing that sites rich in adenine (A) and guanine (G) were prone to binding. Through the enrichment analysis of binding sites, a total of 199 BPDE-adduct target genes were identified, with the majority located on chromosomes 1, 5, 7, 12, 17, and X. The GO analysis indicated that these target genes were mainly enriched in nucleic acid and protein binding, participating in the regulation of catalytic activity, transport activity, translation elongation factor activity, and playing important roles in cell division, differentiation, motility, substance transport, and information transfer. The KEGG analysis revealed that these target genes were primarily enriched in pathways related to cardiovascular diseases, cancer, and immune-inflammatory responses. Conclusion Using ChIP-Seq, 199 BPDE adduct target genes at genome-wide level are identified, impacting biological functions such as cell division, differentiation, motility, substance transport, and information transfer. These genes are closely associated with cardiovascular diseases, tumors, and immune-inflammatory responses.

Objective To investigate the relationship between the development of terminal rectal ganglion and spinal cord/sacral abnormalities in boys with complex anorectal malformations(ARMs)in order to improve the understanding of rectal ganglion development abnormalities in ARMs patients.Methods A retrospective trial was conducted on the male patients with complex ARMs admitted to our hospital from 2015 to 2021.The terminal rectal specimens were taken from them during anoplasty.According to the findings on development of terminal rectal ganglion after HE staining,the patients were classified into G1 group(ganglion cells observed)and G2 group(no ganglion cells observed).Imaging techniques were used to evaluate whether there were abnormalities in the spinal cord and sacrum,and their correlation with the terminal rectal ganglion development was analyzed.Results A total of 139 patients were enrolled,and their median age at anoplasty was 5.77(4.57,6.97)months.There were no significant differences between the G1(n=80,57.6％)and G2(n=59,42.4％)groups in ARMs pathological type(P=0.706)and age at surgery(P=0.140).Radiological findings showed there were 48 cases(34.5％)of spinal cord anomalies(SCA),25 cases(18.0％)of sacral abnormalities and 18 cases(12.9％)of coccyx abnormalities.No significant differences were observed in the incidences of SCA and sacral abnormalities between the G1 and G2 groups(P＜0.05).Moreover,the differences of fatty filum terminale and syrinx were statistically significant(P＜0.05).In addition,the ratio of sacrum to coccyx between the G1 and G2 groups were 0.72±0.10 vs 0.67±0.12(P＜0.05)of the anteroposterior position and 0.77±0.09 vs 0.72±0.09(P＜0.05)of the lateral position.Multivariate logistic regression analysis showed that sacral abnormalities,fatty filum terminale and syrinx were independent predictors of rectal terminal ganglion absence in male patients with complex ARMs.Conclusion The development of terminal rectal ganglia in male patients with ARMs is closely associated with the abnormalities of spinal cord and sacrum.Sacral abnormalities,fatty filum terminale and syrinx are independent predictors of rectal terminal ganglion absence in male patients with complex ARMs.

Background Benzo[a]pyrene (BaP) has neurotoxicity, which can induce the loss of hippocampal neurons in humans and animals and lead to spatial learning and memory dysfunction, but its mechanism is still unclear. Objective To observe the ferroptosis of mouse hippocampal neuron HT22 cells induced by 7,8-dihydroxy-9,10-epoxybenzo[a]pyrene (BPDE), an active metabolite of BaP, and to explore its potential mechanism, so as to provide a basis for the study of BaP neurotoxicity mechanism. Method Mouse hippocampal neuron HT22 cells were selected and divided into four groups: solvent control group and low, medium, and high concentration BPDE exposure groups (0.25, 0.50, and 0.75 μmol·L⁻¹). Cell survival was detected by CCK8 method. Cell morphology and ultrastructure were observed under light and electron microscopes. The levels of reactive oxygen species (ROS) and Fe²⁺ were detected by fluorescence probe method. Iron, 4-hydroxynonenoic acid (4-HNE), malondialdehyde (MDA), glutathione (GSH), and glutathione peroxidase (GSH-PX) levels were detected with commercial kits. The expression levels of acyl-CoA synthase long chain family member 4 (ACSL4), cyclooxygenase 2 (COX2), solute carrier family 7 member 11 (SLC7A11), and glutathione peroxidase 4 (GPX4) were detected by Western blotting. After interventions with ferroptosis inhibitors 20 μmol·L⁻¹ deferoxamine (DFO) and 10 μmol·L⁻¹ ethyl 3-amino-4-cyclohexylaminobenzoate (Fer-1), the cell survival rate of each BPDE exposure group and the changes of the ferroptosis characteristic indicators and protein expression levels were observed. Results With the increase of BPDE concentration, the survival rate of HT22 cells decreased gradually, and the survival rate of each BPDE group was significantly lower than that of the solvent control group (P<0.01). Under light microscope, the number of cells in the high concentration BPDE group was significantly reduced, and atrophic cells and reduced synapses were recorded. Under electron microscope, the HT22 cells in the high concentration BPDE group showed mitochondrial shrinkage, decreased crista, and increased mitochondrial membrane density. Compared with the solvent control group, the levels of intracellular lipid ROS, Fe²⁺, 4-HNE, and MDA significantly increased in the high concentration group (P<0.01), the GSH and GSH-PX levels were significantly decreased (P<0.01), the protein expression levels of ASCL4 and COX2 were significantly increased (P<0.01), and the protein expression levels of SCL7A11 and GPX4 were significantly decreased (P<0.01). The ferroptosis inhibitors DFO and Fer-1 significantly reversed the cell survival rate (P<0.01), the ferroptosis characteristic indicators (ROS, Fe²⁺, 4-HNE, MDA, GSH, and GSH-PX levels) (P<0.01), and the expression levels of ferroptosis-related proteins (ACSL4, COX2, SLC7A11, and GPX4) (P<0.01) in the high concentration BPDE group. Conclusion BPDE can induce ferroptosis in mouse hippocampal neuron HT22 cells, which may be related to the inhibition of SLC7A11/GSH/GPX4 axis and the induction of iron metabolism disorder.

Objective:To compare the differences in lung function between sanitation workers and the general population undergoing routine physical examinations, and to analyze the risk factors for restricted airflow and severity of the condition in sanitation workers.Methods:This study is a large cross-sectional study called "Shanxin Respiratory Health Screening for Ten Thousand People". A total of 1 036 sanitation workers (sanitation group) and 6 701 individuals from the general population undergoing routine physical examinations (control group) were selected as the original study subjects from June 2021 to April 2022 (before matching). Both groups underwent pre-bronchodilator lung function tests, and the differences in lung function characteristics between the two groups were compared. The sanitation group also completed a questionnaire survey. Multivariate and ordinal multinomial logistic regression analysis were used to analyze the risk factors for airflow limitation and its severity.Results:A total of 1 027 individuals from the sanitation group and 999 individuals from the control group were included in the study. There were no significant differences in age, gender, height, weight, and body mass index (BMI) between the two groups (all P>0.05). The rate of airflow restriction was significantly higher in the sanitation group compared to the control group (22.88% vs 8.81%, P<0.001). In the sanitation group, there was no statistically significant difference in a self-assessment test for chronic obstructive pulmonary disease (CAT) scores between individuals with airflow restriction (235 cases) and those without airflow restriction (792 cases) [(1.50±2.50) vs (1.15±2.03) points, P=0.084]. There were no statistically significant differences in forced vital capacity (FVC) as a percentage of predicted value (FVC%pred) between the two groups. However, the sanitation group had significantly lower %pred for forced expiratory volume in one second (FEV 1%pred), FVC/FEV 1 ratio (FEV 1/FVC%pred), forced expiratory flow at 50% of FVC (FEF 50%%pred), forced expiratory flow at 75% of FVC (FEF 75%%pred), and maximal mid-expiratory flow (MMEF%pred) compared to the control group (all P<0.05). The rates of abnormal FEF 50%%pred, FEF 75%%pred, and MMEF%pred were significantly higher in the sanitation group compared to the control group (17.62% vs 10.31%, 17.04% vs 10.01%, 27.26% vs 18.41%, all P<0.001). Small airway parameters and the rate of airflow restriction were significantly higher in past and current smokers of the sanitation group compared to never smokers (all P<0.05). Multifactorial analysis showed that high BMI ( OR=0.929, 95% CI: 0.885-0.974) was a protective factor for airflow restriction, while high smoking index was a risk factor ( OR=1.020, 95% CI: 1.011-1.030). Ordered multinomial logistic regression analysis showed that high BMI ( OR=0.925, 95% CI: 0.882-0.971) was a protective factor for the severity of airflow restriction, while high smoking index ( OR=1.020, 95% CI: 1.011-1.029) was a risk factor for the severity of airflow restriction. Conclusions:The incidences of airflow limitation and small airway abnormalities in sanitation workers are higher than that in general physical examination population. High smoking index and low BMI are independent risk factors for airflow limitation and its severity.

Background The altered expressions of hippocampal N-methyl-D-aspartate (NMDA) receptors induced by benzo[ɑ]pyrene (BaP) causes short-term spatial learning and memory impairment in humans and animals, but whether BaP causes alterations of NMDA receptor subunits in other brain regions and the associated neurotoxic mechanism is still essentially unknown. Objective To observe the mRNA expressions of NR1, NR2A, and NR2B of NMDA receptor subunits in different brain regions in SD rat model with subchronic exposure to BaP, and to provide a basis for in-depth study of the mechanism of BaP-induced neurotoxicity. Methods Forty male SD rats were selected and randomly divided into a control group and 1.00, 2.50, and 6.25 mg·kg⁻¹ BaP exposure groups with 10 rats in each group. The exposure rats received intraperitoneal injection of BaP every other day for 90 d.The average latency to platform, the average total distance, and the duration spent in previous quadrant were measured by the Morris Water Maze. Real-time fluorescence quantitative PCR was used to detect the mRNA expressions of NR1, NR2A, and NR2B in hippocampus, cortex, cerebellum, and striatum of rats. Results The average latency to platform and the average total distance in the 2.50 and 6.25 mg·kg⁻¹ BaP groups were significantly prolonged compared with the control group (P<0.05), and the duration that rats spent in previous quadrant in the 6.25 mg·kg⁻¹ BaP group was significantly shortened (P<0.05). Compared with the control group, the mRNA expressions of NR1 and NR2B in the hippocampus in the 2.50 and 6.25 mg·kg⁻¹ BaP groups were significantly reduced (P<0.05), and the NR2A mRNA expression in the hippocampus in the 6.25 mg·kg⁻¹ BaP group was significantly reduced (P<0.05); the mRNA expressions of NR1 and NR2B in the cortical tissue in the 6.25 mg·kg⁻¹ BaP group were significantly reduced (P<0.05), and the mRNA expression of NR2A in the cortical tissue in the 1.00 mg·kg⁻¹ BaP group was reduced; the mRNA expression of NR2B in the cerebellar tissue in the 6.25 mg·kg⁻¹ BaP group was significantly reduced (P<0.05); there were no differences in the mRNA expressions of NMDA receptor subunits in the striatum tissue (P>0.05). Conclusion Subchronic BaP exposure can cause short-term spatial learning and memory impairment in rats, which may be related to the down-regulation of mRNA expressions of NR1, NR2A, and NR2B in hippocampus, changes of mRNA expressions of NR1, NR2A, and NR2B in cortical area, and the down-regulation of NR2B mRNA expression in cerebellum.

Computed tomography (CT) examination is the major measure for detecting and diagnosis of foreign bodies in human body. Although CT has high sensitivity in diagnosis of foreign body, some interference factors may still lead to missed diagnosis or misdiagnosis. Here we report a rare case that a bamboo stick accidentally pierced into the left chest of a young man who was drunk and unware of this hurt. The patient experienced cough, chest pain, fever, hemoptysis, and was misdiagnosed as primary and secondary tuberculosis based on chest CT examinations at a local hospital, although no tubercular bacillus detected by sputum smear. He subsequently received anti-tuberculous treatments in the following three years, but no improvement of his symptoms was observed. Until one month before his death, the bamboo stick was detected by spiral CT examination as well as three-dimensional image reconstruction at another hospital. Postmortem examination revealed pneumonia, pulmonary infarction, and abscess as the causes of his death. We analyze the potential reasons of misdiagnosis in this case, aiming to provide reference for the diagnosis and treatment of pulmonary inflammation associated with foreign body in the future.
Abscess ; Diagnostic Errors ; Humans ; Male ; Pneumonia ; Pulmonary Infarction ; Tuberculosis, Pulmonary

Objective To compare the efficacy and safety of the long-term intermittent maintenance treatment with tacrolimus 0.03％ ointment versus traditional treatment in reducing relapses and prolonging the recurrence interval in children with moderate to severe atopic dermatitis (AD).Methods A two-phase randomized,open-labelled,controlled clinical trial was conducted from September 2012 to November 2013.In the first phase,a total of 171 children aged 2-15 years with moderate to severe AD were enrolled from 7 hospitals in China,and received conventional treatment with tacrolimus 0.03％ ointment twice a day for 2-6 weeks.At the end of the treatment,the patients who achieved an investigator's global assessment (IGA) score ≤ 2 (n =125) were randomly classified into 2 groups to receive the second-phase treatment:test group (n =62) receiving intermittent maintenance treatment with tacrolimus 0.03％ ointment twice a week (Monday and Thursday),and control group (n =63) receiving no treatment.If the patients in the 2 groups experienced relapse,they received conventional treatment with tacrolimus 0.03％ ointment twice a day.The overall observation period was 6 months.The primary endpoint was the time to the first relapse,which was defined as the number of days from the end of the first-phase treatment to the first relapse.The secondary endpoints included the number of relapses at the second-phase trial,the disease severity at the time of relapse,the duration of relapse,the pruritus score at the time of relapse,the total amount of tacrolimus ointment used,the total response rate at the second-phase trial,and the incidence of adverse events.Results A total of 125 children with AD were enrolled into the second-phase trial,and 121 of them completed the follow-up.Among the 121 patients,the recurrence rate was significantly lower in the test group (25/60,41.7％) than in the control group (46/61,75.4％;x2 =14.20,P ＜ 0.001).The time to the first relapse was significantly longer in the test group (46.9 ± 37.7 d) than in the control group (28.8 ± 32.3 d;Z =1 093.50,P =0.020).The total number of recurrence was 31 and 86 in the test group and control group respectively,and the mean number of recurrence in each patient was significantly lower in the test group (0.52 ± 0.68) than in the control group (1.41 ± 1.23,t =4.96,P ＜ 0.001).There were no significant differences between the two groups regarding disease severity during relapse (eczema area and severity index:Z =971.50,P =0.39),duration of relapse (Z =747.00,P =0.07),and pruritus score during relapse (Z =894.00,P =0.95).The therapeutic drug was tolerated well in all the children,and no tacrolimus-related serious adverse events occurred.Conclusion The intermittent maintenance treatment with tacrolimus 0.03％ ointment twice a week for 6 months can effectively and safely prevent and reduce relapses,and prolong the recurrence interval in children with moderate to severe AD.

Objective To evaluate the reliability, validity and applicability of the family caregiver burden scale (CBS-CP) for cancer patients. Methods The family caregivers of patients with digestive system cancer were selected as the research subjects. The reliability was evaluated by applying the Cronbach alpha coefficient and the half confidence level. The validity was evaluated by using criterion related validity. Applicability evaluation included: to analyze the burden level of family caregivers of patients with digestive system cancer;and to explore the influencing factors of caregiver burden. Results Except for factor 5, the Cronbach's alpha coefficient and the half coefficient level of the total CBS-CP and the other 4 factors were all higher than 0.75. The total scores and factors of CBS-CP were positively correlated with depression and anxiety (all P<0.01,r=0.296-0.505), and negatively correlated with the quality of life [except for the relationship between factor 5 and physical component summary score (P<0.05), the remaining Ps<0.01, r=0.126-0.370]. The total caregiver burden score ranged from 0 to 109, with an average of 46.03 ± 22.96;multiple regression analysis showed that the possible predictor variables of the total caregiver burden included:anxiety/depression, the disturbed life of family caregivers, quality of life, family economic pressure, spouse caregivers and caregivers'health status. Conclusions The findings showed that both the reliability and validity of the CBS-CP were good. The burden of family caregivers in patients with digestive system cancer is generally at a mild level, and the factors affecting the caregiver burden included physical, psychological, social and economic aspects. It was proposed that the influencing factors of caregiver burden should be explored through the dyadic level of caregivers and patients in future research, so as to provide scientific basis for the development of relevant interventions.