Objective To investigate the sputum metabolic profiles of patients with occupational coal workers' pneumoconiosis (CWP) by an untargeted metabolomics method, and to identify relevant differential metabolic pathways and potential biomarkers. Methods A total of 12 male patients with stage Ⅰ CWP were selected as the CWP group, and 16 healthy male individuals were selected as the control group, using a judgmental sampling method. Sputum metabolites of individuals in both groups were detected to perform non-targeted metabolomic analysis using the ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Differential metabolites (DMs) and their pathways were screened using principal component analysis, partial least squares discriminant analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Potential biomarkers were analyzed and identified via the receiver operating characteristic curve (ROC). Results There were apparent metabolic alterations observed in sputum of CWP patients compared with healthy controls. In the positive ion mode, a total of 42 DMs were identified in sputum from CWP patients, including 19 downregulated and 23 upregulated metabolites. In the negative ion mode, a total of 25 DMs were identified in sputum from CWP patients, including 16 downregulated and 9 upregulated metabolites. KEGG enrichment analysis of sputum from CWP patients showed that seven DMs pathways were enriched in ABC transporters, histidine metabolism, phenylalanine metabolism, arachidonic acid metabolism, linoleic acid metabolism, purine metabolism, and oxidative phosphorylation, involving 26 DMs. ROC analysis indicated that 16(R)-hydroxyarachidonic acid, pyrophosphate, and 2-hydroxyphenylacetate of these 26 DMs may serve as potential biomarkers for CWP. Conclusion Sputum metabolomic profiles were altered in CWP patients compared with healthy controls. The potential biomarkers of CWP prevention and treatment are 16(R)-hydroxyarachidonic acid, pyrophosphate, and 2-hydroxyphenylacetate.

Objective The aim of this study was to explore the role and mechanism of ferroptosis in SiO2-induced cardiac injury using a mouse model. Methods Male C57BL/6 mice were intratracheally instilled with SiO2 to create a silicosis model.Ferrostatin-1(Fer-1)and deferoxamine(DFO)were used to suppress ferroptosis.Serum biomarkers,oxidative stress markers,histopathology,iron content,and the expression of ferroptosis-related proteins were assessed. Results SiO2 altered serum cardiac injury biomarkers,oxidative stress,iron accumulation,and ferroptosis markers in myocardial tissue.Fer-1 and DFO reduced lipid peroxidation and iron overload,and alleviated SiO2-induced mitochondrial damage and myocardial injury.SiO2 inhibited Nuclear factor erythroid 2-related factor 2(Nrf2)and its downstream antioxidant genes,while Fer-1 more potently reactivated Nrf2 compared to DFO. Conclusion Iron overload-induced ferroptosis contributes to SiO2-induced cardiac injury.Targeting ferroptosis by reducing iron accumulation or inhibiting lipid peroxidation protects against SiO2 cardiotoxicity,potentially via modulation of the Nrf2 pathway.

Background Job burnout is common among working populations. The current situation and influencing factors of job burnout have been studied in workers of many industries at home and abroad, except the express industry in China. Objective To understand the current situation of job burnout in express industry in a city of China, and to provide a scientific basis for developing measures to reduce the occurrence of job burnout. Methods In 2022, 432 express delivery workers in a city were selected by cluster random sampling, and their job burnout, anxiety symptoms, and depressive symptoms were evaluated by using the General Burnout Scale, Generalized Anxiety Disorder-7, and Patient Health Questionnaire-9. Chi-square test was used to compare inter-group positive rates of job burnout. Spearman correlation analysis was used to analyze the correlation between selected variables. Positive job burnout, high level of exhaustion, and high level of cynicism were selected as dependent variables. Single-factor analysis was firstly carried out to identify statistically significant variables for subsequent logistic regression analysis. Results A total of 460 questionnaires were distributed and 432 valid questionnaires were recovered, with an effective recovery rate of 93.9%. There were 286 (66.2%) express delivery workers reporting job burnout. The positive rate of anxiety symptoms was 41.0%, and the positive rate of depressive symptoms was 34.0%. The job burnout score of the express industry workers [M (P₂₅, P₇₅)] was 1.8 (1.0, 2.5); the scores [M (P₂₅, P₇₅)] of exhaustion, cynicism, and professional efficacy were 1.0 (0.0, 2.6), 1.0 (0.0, 2.2), and 3.5 (1.2, 5.8), respectively; the score [M (P₂₅, P₇₅)] of anxiety symptoms was 1.5 (0.0, 7.0); the score [M (P₂₅, P₇₅)] of depressive symptoms was 1.0 (0.0, 8.0). There were statistical differences in the positive rates of job burnout among the express industry workers grouped by gender, education, monthly income, work shift system, overtime, anxiety symptoms, and depressive symptoms (P<0.05). The Spearman correlation analysis showed that there were significant positive correlations between the score of anxiety symptoms and the scores of job burnout, exhaustion, and cynicism (r_s=0.596, 0.689, 0.600, P<0.001); the score of depressive symptoms was also positively correlated with the scores of job burnout, exhaustion, and cynicism (r_s=0.601, 0.680, 0.607, P<0.001). The logistic regression analysis showed that women had a lower risk of job burnout than men (OR=0.458, 95%CI: 0.273, 0.768), and the risk of reporting positive job burnout was 3.140 times higher for those who worked overtime than those who did not (OR=3.140, 95%CI: 1.732, 5.693). Conclusion The current situation of job burnout in express industry is serious. Gender, education, monthly income, and overtime are the main influencing factors. Measures should be developed to reduce the occurrence of job burnout.

Background Job burnout is prevalent among the occupational population, which may lead to individual physical and mental discomfort and affect the quality of life and productivity of suffered workers. Most current chemical fiber factory workers are engaged in hazardous tasks with high frequency and high repetition, which are highly associated with anxiety and depressive symptoms, and subsequently lead to job burnout. Objective To understand the current situation and influencing factors of job burnout in workers of a chemical fiber factory in Xinxiang City of Henan Province, and to provide empirical evidence for preventing and reducing the occurrence of job burnout in target workers. Methods In 2022, the workers of a chemical fiber factory in Xinxiang City were selected by cluster random sampling. The Chinese versions of the Burnout Scale, Generalized Anxiety Disorder-7, and Patient Health Questionnaire-9 were used to conduct a survey. SPSS 25.0 software was used for rank sum test, correlation analysis, and logistic regression analysis. Results A total of 1463 valid questionnaires were collected, with an effective recovery rate of 90.0%. The positive rate of mild and moderate job burnout in the chemical fiber factory employees was 39.4%, and the positive rate of serious job burnout was 14.3%. There were statistical differences in the positive rates of job burnout among the workers by gender, age, education level, position, work shift system, anxiety symptom severity, and depressive symptom severity (P<0.05). The results of Spearman correlation analysis showed that the score of anxiety symptoms was positively correlated with the total score of job burnout, as well as the dimensional scores of exhaustion and cynicism, and negatively correlated with the dimensional score of professional efficacy (r=0.671, 0.764, 0.673, −0.097; P<0.01). The score of depressive symptoms was also positively correlated with the total score of job burnout, as well as the dimensional scores of exhaustion and cynicism, and negatively correlated with the dimensional score of professional efficacy (r=0.688, 0.791, 0.723, −0.087; P<0.01). The results of logistic regression analysis showed that men had a higher risk of serious job burnout than women (OR=1.698, 95%CI: 1.163-2.479); workers aged ≤ 40 years old had a higher probability of serious job burnout than those aged 51 to 60 years old (OR=2.587, 95%CI: 1.310-5.109); non-assembly line production workers and assembly line production workers were more prone to serious job burnout than administrative management and logistics personnel (OR=6.511, 9.707, 95%CI: 1.539-27.548, 2.260-41.700); compared with other shift systems (three shifts and night shifts), the probability of serious job burnout was lower (OR=0.375, 95%CI: 0.254-0.553) in regular day shift workers; compared with frequent overtime work, those reporting no overtime work and occasional overtime work showed a lower risk of serious job burnout, with OR (95%CI) values of 0.114 (0.068-0.192) and 0.331 (0.194-0.564), respectively. Conclusion The positive rate of job burnout among the employees of the chemical fiber factory is high, and the anxiety symptoms and depressive symptoms are positively correlated with job burnout. Adjustment of work should be strengthened at multiple levels to improve anxiety symptoms and depressive symptoms of employees, and reduce the occurrence of job burnout.

Objective:To explore the speech features of female patients with anhedonic depression and their recognition of pleasure deficient symptoms.Methods:A total of 102 female depression patients who were hospitalized at Nanjing Brain Hospital from September 2020 to October 2021 were selected, including 62 anhedonic depression patients (anhedonic group) and 40 non-anhedonic depression patients (non-anhedonic group). A total of 50 female healthy controls were recruited during the same period.All participants were evaluated by the 17-item Hamilton depression scale (HAMD-17), Snaith-Hamilton pleasure scale (SHAPS), and the temporal experience of pleasure scale (TEPS), as well as voice acquisition.SPSS 23.0 software was used for data processing.Statistical analysis was conducted using one-way ANOVA, non-parametric tests, Logistic regression, and receiver operating characteristic curve.Results:Compared with the non-anhedonic group, the anhedonic group showed significant changes in 15 voice features(all P<0.05), including Mel-frequency cepstral coefficients, formant frequencies, intensity, and energy features.Among these features, Mel-frequency cepstral coefficients exhibited the highest accuracy in identifying anhedonic depression, with sensitivity of 47.5%, specificity of 91.9%, area under curve (AUC) of 0.751, 95% CI=0.686-0.866.Formant frequencies could identify female anhedonic depression, with a sensitivity of 90.0%, a specificity of 40.3%, an AUC of 0.647, and 95% CI=0.605-0.824.Energy features could identify anhedonic deficient depression, with a sensitivity of 60.0%, a specificity of 74.2%, an AUC of 0.679, and 95% CI=0.587-0.804.Intensity features could identify female anhedonic depression, with a sensitivity of 70.0%, a specificity of 58.1%, an AUC of 0.640, and 95% CI=0.554-0.769. Conclusion:Mel-frequency cepstral coefficients, formant frequencies, intensity features, and energy features may have specific changes in female patients with anhedonic depression.The Mel-frequency cepstral coefficients has the highest recognition accuracy for anhedonic symptoms in female depression patients, and is expected to become an objective evaluation index for female anhedonic depression.

Objective:The aims of this study were to investigate the effect of gas explosion on rats and to explore the pulmonary function alterations associated with gas explosion-induced acute blast lung injury (ABLI) in real roadway environment.Methods:In April 2018, the large coal mine gas explosion test roadway and explosion test system were used to simulate the real gas explosion roadway environment, fixed the cage and set the explosion parameters. 72 SD rats, male, SPF grade, were randomly divided into nine groups by completely random grouping method according to their body weight: control group, close range group (160 m) , and long range group (240 m) . In each group, there were wound groups (24 h group and 48h group, 8/group, total 48 in six groups) and no wound groups (8/group, total 24 in three groups) . Except for the control group, the other groups were placed in cages at different distances under anesthesia, the experiment of gas explosion was carried out by placing the rats in a position that could force the lungs. The changes of respiratory function of the rats in the non-invasive group were monitored with pulmonary function instrument at 2 h, 24 h, 48 h, 72 h and 168h after the explosion, and were killed under anesthesia 7 days later; the rats in invasive groups were anesthetized and killed at 24 h, 48 h and 168 h, respectively. Gross observation, lung wet-dry ratio and lung histopathology were performed.Results:Compared with the control group, f (respiratory frequency, f) , MV (minute ventilation, MV) , PEF (peak expiratory flow rate, PEF) , PIF (peak inspiratory flow rate, PIF) and EF50 (1/2 tidal volume expiratory flow, EF50) of rats in the close and long range groups decreased significantly after gas explosion 2 h. PAU (respiration pause, PAU) , Te (expiratory time, Te) , Ti (inspiratory time, Ti) and Tr (relaxation time, Tr) were significantly increased ( P<0.05) . After 48 h, TV (tidal volume, TV) , Penh (enhanced respiration pause, Penh) , PAU, and PIF of rats in the long range group were significantly increased ( P<0.05) . After 72 h, MV in the long range group was significantly decreased ( P<0.05) . Compared with the control group, Penh, PAU, Ti and Te were significantly decreased after 168 h in the close and long range groups, with statistical significance ( P<0.05) . At the same time, the body weight of rats in different range groups was significantly decreased ( P<0.05) . In addition, both HE staining and routine observation of lung tissues of rats in different range groups showed that gas explosion caused pulmonary edema, obviously congested pulmonary capillaries, a large number of inflammatory cells and infiltrated red blood cells. Conclusion:Gas explosion in real roadway environment can cause the change of respiratory function phase and lung tissue damage in rats, suggesting that the model of gas explosion-induced ABLI has been initially established successfully, which would provide a basis for further study on the pathogenesis of ABLI.

Objective:To analyze the changes of serum metabolomics in rats with combined injuries caused by gas explosion and explore its possible mechanism.Methods:In April 2018, the large coal mine gas explosion test roadway and explosion test system were used to simulate the gas explosion experiment. All 32 SD rats were randomly divided into four groups, control group (not involved in the explosion) , close range (40 m) group, medium range (160 m) group and long range (240 m) group, 8 in each group. The respiratory function at 2 hours and the neural behavior at 48 hours were detected after the explosion. The rats were anesthetized and sacrificed after 48 hours, and the serum, lung, liver and other tissues of the rats were isolated and histopathological changes of lung and liver tissues were observed by HE staining. Serum samples were detected by liquid chromatography-high resolution mass spectrometry (UPLC-Orbitrap Elite/MS) , and metabolic spectrum differences between groups were evaluated by principal component analysis. Differential metabolites were screened and identified, and metabolic pathways were analyzed.Results:Compared with control group, respiratory function indexes (respiratory frequency, minute ventilation, peak inspiratory flow rate, peak expiratory flow rate and 1/2 tidal volume expiratory flow) of rats in different explosion groups were significantly decreased ( P<0.05) , but respiration pause, inspiratory time and 2/3 tidal volume required time were significantly increased ( P<0.05) in 2 hours after the explosion. However, the residence times of the neurobehavioral indicators of the 40 m group and 160 m group were significantly increased ( P<0.05) , and the movement distances were significantly decreased ( P<0.05) in 48 hours after the explosion. HE staining results showed that the lung and liver tissues of the rats in the gas explosion group structurally damaged, and the cells were disordered, with inflammatory cell infiltration, bleeding and edema. Metabonomics analysis showed that there were significant differences in metabolic profiles between groups. A total of 18 differential metabolites were identified in serum samples, including aconitum acid, citric acid, niacinamide and pyruvate, which involved in 12 major metabolic pathways, including the glutamic acid and glutamine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, glyoxylic acid and dicarboxylic acid metabolism, phenylalanine metabolism, nicotinic acid and nicotinamide metabolism, citric acid cycle (TCA cycle) . Conclusion:Gas explosion can cause multi-organ system damage in rats, the mechanism of which may be related to the biosynthesis of alanine, tyrosine and tryptophan, metabolism of niacin and niacinamide, metabolism of acetaldehyde and dicarboxylic acid, and TCA cycle, etc.

Objective:To investigate the expression of lipoic acid synthase gene ( LIAS) and nuclear factor-erythroid 2-related factor 2 gene ( NRF2) in peripheral blood mononuclear cells (PBMCs) from patients with silicosis and their correlation with silicosis. Methods:A total of 45 healthy controls and 107 patients with silicosis were randomly selected in this study in May 2019. PBMCs were isolated from peripheral blood and NRF2 protein expression was detected by immunofluorescence. The mRNA levels of LIAS and NRF2 in PBMCs were determined by real-time PCR. The dose-response relationship beween LIAS and NRF2 mRNA expression levels and their association with silicosis were analyzed by restricted cubic spline (RCS) and logistic regression. Results:Compared with the control group, the number of monocytes in the case group was significantly increased, and the forced expiratory volume in the first second (FEV 1.0) decreased, the difference was statistically significant ( P<0.05) . The positive expression rate of NRF2 in PBMCs of silicosis patients in stage Ⅰ group was significantly higher than that in the control group, and the positive expression rate of NRF2 in silicosis patients in stageⅡ and Ⅲ groups was lower than that in silicosis patients in control group and stage Ⅰ group ( P<0.01) . Results of RCS showed that there was a linear dose-response relationship between LIAS and NRF2 mRNA expression (overall correlation test, χ 2=213.710, P<0.01; non-linear test, χ 2=1.340, P=0.511) . There was a positive correlation between mRNA expression of LIAS and that of NRF2 ( r=0.651, P<0.01) . The results of multivariate analysis showed that LIAS and NRF2 were increased the risk of incidence in silicosis patients with stageⅠ ( OR=11.184, 4.332, P<0.05) and NRF2 was the protective factor in silicosis patients with stage Ⅱ and Ⅲ ( OR=0.225, 0.208, P<0.05) after adjusting for potential confounding factors including age, education level, BMI and smoking. Conclusion:There is a linear dose-response relationship between the expression of LIAS and NRF2 mRNA in PBMCs of silicosis patients, LIAS and NRF2 are involved in the pathogenesis of silicosis.

Objective:The aims of this study were to investigate the effect of gas explosion on rats and to explore the pulmonary function alterations associated with gas explosion-induced acute blast lung injury (ABLI) in real roadway environment.Methods:In April 2018, the large coal mine gas explosion test roadway and explosion test system were used to simulate the real gas explosion roadway environment, fixed the cage and set the explosion parameters. 72 SD rats, male, SPF grade, were randomly divided into nine groups by completely random grouping method according to their body weight: control group, close range group (160 m) , and long range group (240 m) . In each group, there were wound groups (24 h group and 48h group, 8/group, total 48 in six groups) and no wound groups (8/group, total 24 in three groups) . Except for the control group, the other groups were placed in cages at different distances under anesthesia, the experiment of gas explosion was carried out by placing the rats in a position that could force the lungs. The changes of respiratory function of the rats in the non-invasive group were monitored with pulmonary function instrument at 2 h, 24 h, 48 h, 72 h and 168h after the explosion, and were killed under anesthesia 7 days later; the rats in invasive groups were anesthetized and killed at 24 h, 48 h and 168 h, respectively. Gross observation, lung wet-dry ratio and lung histopathology were performed.Results:Compared with the control group, f (respiratory frequency, f) , MV (minute ventilation, MV) , PEF (peak expiratory flow rate, PEF) , PIF (peak inspiratory flow rate, PIF) and EF50 (1/2 tidal volume expiratory flow, EF50) of rats in the close and long range groups decreased significantly after gas explosion 2 h. PAU (respiration pause, PAU) , Te (expiratory time, Te) , Ti (inspiratory time, Ti) and Tr (relaxation time, Tr) were significantly increased ( P<0.05) . After 48 h, TV (tidal volume, TV) , Penh (enhanced respiration pause, Penh) , PAU, and PIF of rats in the long range group were significantly increased ( P<0.05) . After 72 h, MV in the long range group was significantly decreased ( P<0.05) . Compared with the control group, Penh, PAU, Ti and Te were significantly decreased after 168 h in the close and long range groups, with statistical significance ( P<0.05) . At the same time, the body weight of rats in different range groups was significantly decreased ( P<0.05) . In addition, both HE staining and routine observation of lung tissues of rats in different range groups showed that gas explosion caused pulmonary edema, obviously congested pulmonary capillaries, a large number of inflammatory cells and infiltrated red blood cells. Conclusion:Gas explosion in real roadway environment can cause the change of respiratory function phase and lung tissue damage in rats, suggesting that the model of gas explosion-induced ABLI has been initially established successfully, which would provide a basis for further study on the pathogenesis of ABLI.