OBJECTIVE To investigate the effects and potential mechanism of persimmon leaf （PL） extract against ferroptosis induced by H2O2 in IEC-6 cells. METHODS Using IEC-6 cells as object， the effects of ferroptosis inhibitor ferrostatin-1 on IEC-6 cell viability induced by H2O2 were investigated； IEC-6 cells were divided into control group， H2O2 group， H2O2+PL 25 μg/mL group and H2O2+PL 50 μg/mL group. The levels of oxidant stress indexes [content of malondialdehyde （MDA）， activity of superoxide dismutase （SOD）， and levels of reactive oxygen species （ROS）]， mitochondrial membrane potential （MMP） as well as mRNA and protein expressions of nuclear factor-erythroid-2 related factor 2 （Nrf2）， heme oxygenase-1 （HO-1）， NADPH/quinone oxidoreductase-1 （NQO-1）， cystine/glutamate anti-porter （xCT）， glutathione peroxidase 4 （GPX4） and ferritin heavy chain （FTH） were detected. RESULTS Ferroptosis inhibitor ferrostatin-1 could significantly increase the survival rate of H2O2-induced cells （P＜ 0.01）. Compared with the control group， MDA content， ROS level， mRNA expressions of Nrf2 and NQO-1 as well as protein expressions of Nrf2 and HO-1 were increased or up-regulated significantly， while SOD activity， MMP， mRNA expressions of xCT， GPX4 and FTH as well as protein expressions of GPX4 and FTH were decreased or down-regulated significantly （P＜0.01 or P＜0.05）. Compared with the H2O2 group， oxidative stress Δ indexes of H2O2+PL 25， 50 μg/mL groups were reversed to different extents， MMP level was increased significantly， as well as mRNA and protein expressions of Nrf2， HO-1， NQO-1，xCT， GPX4 and FTH were up-regulated to different extents；there were statistical significances in some indexes between groups （P＜0.01 or P＜0.05）. CONCLUSIONS PL extract can alleviate mitochondrial membrane damage and abnormal accumulation of ROS caused by H2O2， which may be related to the inhibition of ferroptosis by activating the Nrf2/HO-1 signaling pathway.

Background The job content of aircraft maintenance workers is complex, with high intensity and high requirements, and they are prone to work-related musculoskeletal disorders (WMSDs), but related research is relatively rare. Objective To investigate the positive rate of WMSDs among aircraft maintenance workers, evaluate ergonomic load, and analyze the risk factors of WMSDs. Methods We used a self-compiled questionnaire for WMSDs and the Quick Exposure Checklist (QEC) to investigate the basic situation, positive rate of WMSDs, and the ergonomic load of 2271 male maintenance workers in 6 departments of an aircraft maintenance company, including airline maintenance, overall overhaul, accessory/landing gear overhaul, engine overhaul, product customization, and power assist. We used a logistic regression model to analyze the risk factors of WMSDs in the neck, shoulder, hand/wrist, and lower back. Results The positive rate of WMSDs in the past 12 months was 70.4% (1598/2271) and the positive rate of WMSDs in different body parts ranged from 6.6% to 49.5%, with the top three parts of lower back, neck, and knee, respectively. There were statistically significant differences in the positive rate among different departments (P<0.05). The average QEC scores for neck, hand/wrist, and back (static) were moderate, while those for shoulder and back (dynamic) were high, and the body part specific positive rate of WMSDs increased with the increase of ergonomic load level. Working years (5-<10 years, ≥20 years), working with back flexed or twisted or side bent (moderately, excessively), high maximum force level exerted by one hand, and feeling difficult (sometimes, often) and stressful (moderately, very) while working were associated with higher risks of lower back pain (OR=1.486, 1.505; 2.151, 3.769; 1.637; 2.110, 2.407; 1.637, 1.794; P<0.05). Working years (15-<20 years, ≥20 years), working with head/neck bent or twisted (occasionally, continuously), feeling difficult (sometimes) and stressful (very) while working were associated with higher risks of neck pain (OR=1.731, 1.586; 3.732, 8.341; 1.633; 1.696; P<0.05). Working years (15-<20 years, ≥20 years), working with hands in a high position (at shoulder or above), very frequent shoulder/arm movements, feeling difficult (sometimes, often) and stressful (moderately, very) while working were associated with higher risks of shoulder pain (OR=1.587, 1.709; 1.299; 1.521; 1.643, 2.239; 1.659, 1.977; P<0.05). Working with wrist at deviated or bent angle, high repetition of similar movements, feeling difficult (sometimes, often) and stressful (moderately, very) while working were associated with higher risks of hand/wrist pain (OR=1.692; 1.670; 1.827, 2.884; 2.190, 2.625; P <0.05) . Physical exercise after work (≥3 times·week⁻¹) was associated with a lower risk of neck pain (OR=0.582, P<0.05). Shift workers were at a lower risk of shoulder pain and hand/wrist pain (OR=0.737 and 0.554, P<0.05). Conclusion The high positive rate of WMSDs symptoms among aircraft maintenance workers is related to individual, occupational ergonomic, and psychological factors, and active prevention and intervention should be taken.

Background/Aims: Dexamethasone (DEX) is a widely used exogenous therapeutic glucocorticoid in clinical settings. Its long-term use leads to many side effects. However, its effect on metabolic disorders in individuals on a high-fat diet (HFD) remains poorly understood. Methods: In this study, HFD-fed mice were intraperitoneally injected with DEX 2.5 mg/kg/day for 30 days. Lipid metabolism, adipocyte proliferation, and inflammation were assayed using typical approaches. Results: DEX increased the epididymal fat index and epididymal adipocyte size in HFD-fed mice. The number of epididymal adipocytes with diameters > 70 μm accounted for 0.5% of the cells in the control group, 30% of the cells in the DEX group, 19% of the cells in the HFD group, and 38% of all the cells in the D+H group. Adipocyte proliferation in the D+H group was inhibited by DEX treatment. Adipocyte enlargement in the D+H group was associated with increased the lipid accumulation but not the adipocyte proliferation. In contrast, the liver triglyceride and total cholesterol levels and their metabolism were downregulated by the same treatment, indicating the therapeutic potential of DEX for nonalcoholic fatty liver disease. Conclusions DEX synergizes with HFD to promote lipid deposition in adipose tissues. A high risk of obesity development in patients receiving HFD and DEX treatment is suggested.

Background/Aims: Dexamethasone (DEX) is a widely used exogenous therapeutic glucocorticoid in clinical settings. Its long-term use leads to many side effects. However, its effect on metabolic disorders in individuals on a high-fat diet (HFD) remains poorly understood. Methods: In this study, HFD-fed mice were intraperitoneally injected with DEX 2.5 mg/kg/day for 30 days. Lipid metabolism, adipocyte proliferation, and inflammation were assayed using typical approaches. Results: DEX increased the epididymal fat index and epididymal adipocyte size in HFD-fed mice. The number of epididymal adipocytes with diameters > 70 μm accounted for 0.5% of the cells in the control group, 30% of the cells in the DEX group, 19% of the cells in the HFD group, and 38% of all the cells in the D+H group. Adipocyte proliferation in the D+H group was inhibited by DEX treatment. Adipocyte enlargement in the D+H group was associated with increased the lipid accumulation but not the adipocyte proliferation. In contrast, the liver triglyceride and total cholesterol levels and their metabolism were downregulated by the same treatment, indicating the therapeutic potential of DEX for nonalcoholic fatty liver disease. Conclusions DEX synergizes with HFD to promote lipid deposition in adipose tissues. A high risk of obesity development in patients receiving HFD and DEX treatment is suggested.

Background/Aims: Dexamethasone (DEX) is a widely used exogenous therapeutic glucocorticoid in clinical settings. Its long-term use leads to many side effects. However, its effect on metabolic disorders in individuals on a high-fat diet (HFD) remains poorly understood. Methods: In this study, HFD-fed mice were intraperitoneally injected with DEX 2.5 mg/kg/day for 30 days. Lipid metabolism, adipocyte proliferation, and inflammation were assayed using typical approaches. Results: DEX increased the epididymal fat index and epididymal adipocyte size in HFD-fed mice. The number of epididymal adipocytes with diameters > 70 μm accounted for 0.5% of the cells in the control group, 30% of the cells in the DEX group, 19% of the cells in the HFD group, and 38% of all the cells in the D+H group. Adipocyte proliferation in the D+H group was inhibited by DEX treatment. Adipocyte enlargement in the D+H group was associated with increased the lipid accumulation but not the adipocyte proliferation. In contrast, the liver triglyceride and total cholesterol levels and their metabolism were downregulated by the same treatment, indicating the therapeutic potential of DEX for nonalcoholic fatty liver disease. Conclusions DEX synergizes with HFD to promote lipid deposition in adipose tissues. A high risk of obesity development in patients receiving HFD and DEX treatment is suggested.

Background/Aims: Dexamethasone (DEX) is a widely used exogenous therapeutic glucocorticoid in clinical settings. Its long-term use leads to many side effects. However, its effect on metabolic disorders in individuals on a high-fat diet (HFD) remains poorly understood. Methods: In this study, HFD-fed mice were intraperitoneally injected with DEX 2.5 mg/kg/day for 30 days. Lipid metabolism, adipocyte proliferation, and inflammation were assayed using typical approaches. Results: DEX increased the epididymal fat index and epididymal adipocyte size in HFD-fed mice. The number of epididymal adipocytes with diameters > 70 μm accounted for 0.5% of the cells in the control group, 30% of the cells in the DEX group, 19% of the cells in the HFD group, and 38% of all the cells in the D+H group. Adipocyte proliferation in the D+H group was inhibited by DEX treatment. Adipocyte enlargement in the D+H group was associated with increased the lipid accumulation but not the adipocyte proliferation. In contrast, the liver triglyceride and total cholesterol levels and their metabolism were downregulated by the same treatment, indicating the therapeutic potential of DEX for nonalcoholic fatty liver disease. Conclusions DEX synergizes with HFD to promote lipid deposition in adipose tissues. A high risk of obesity development in patients receiving HFD and DEX treatment is suggested.

Background/Aims: Dexamethasone (DEX) is a widely used exogenous therapeutic glucocorticoid in clinical settings. Its long-term use leads to many side effects. However, its effect on metabolic disorders in individuals on a high-fat diet (HFD) remains poorly understood. Methods: In this study, HFD-fed mice were intraperitoneally injected with DEX 2.5 mg/kg/day for 30 days. Lipid metabolism, adipocyte proliferation, and inflammation were assayed using typical approaches. Results: DEX increased the epididymal fat index and epididymal adipocyte size in HFD-fed mice. The number of epididymal adipocytes with diameters > 70 μm accounted for 0.5% of the cells in the control group, 30% of the cells in the DEX group, 19% of the cells in the HFD group, and 38% of all the cells in the D+H group. Adipocyte proliferation in the D+H group was inhibited by DEX treatment. Adipocyte enlargement in the D+H group was associated with increased the lipid accumulation but not the adipocyte proliferation. In contrast, the liver triglyceride and total cholesterol levels and their metabolism were downregulated by the same treatment, indicating the therapeutic potential of DEX for nonalcoholic fatty liver disease. Conclusions DEX synergizes with HFD to promote lipid deposition in adipose tissues. A high risk of obesity development in patients receiving HFD and DEX treatment is suggested.

Objective:To analyze the clinical features and genetic basis of a child with Disorder of sex development (DSD).Methods:A child who was admitted to the Linyi People′s Hospital for primary amenorrhoea on July 29, 2019 was selected as the study subject. Clinical data of the child was collected. Chromosomal karyotyping and quantitative real-time PCR were used to detect Y chromosome microdeletions and other chromosomal aberrations. Next-generation sequencing was carried out for the child and her parents. Candidate variant was verified by Sanger sequencing and bioinformatic analysis.Results:The child, a 13-year-old girl, has featured primary amenorrhoea and onset of secondary sex characteristics of males. Ultrasound exam had detected no uterus and definite ovarian structure, but narrow band vaginal hypoecho and curved cavernoid structure. The child was found to have a 46, XY karyotype without an AZF deletion. DNA sequencing revealed that she has harbored a maternally derived c. 323delA (p.Q108Rfs*188) variant in the nuclear receptor subfamily 5 group A member 1 ( NR5A1) gene, which may result in a truncated protein. The variant was classified as pathogenic (PVS1+ PM2_Supporting+ PP4) based on the guidelines from the American College of Medical Genetics and Genomics. Conclusion:The NR5A1: c. 323delA variant probably underlay the pathogenesis of 46, XY DSD in this child. The discovery of the novel variant has enriched the mutational spectrum of NR5A1 gene and provided a basis for clinical diagnosis, treatment and prenatal diagnosis.

Background Bus drivers are a high-risk group for work-related musculoskeletal disorders (WMSDs). There are a large number of bus drivers in mega-cities. High volumes of passenger traffic and complexity of road conditions may elevate their risk of WMSDs, but there are few studies related to this group. Objective To investigate the prevalence of WMSDs among bus drivers in a mega-city and to analyze potential influencing factors. Methods Based on cross-sectional study design and self-administered questionnaire, the prevalence of WMSDs in past 12 months were estimated by stratified cluster sampling among bus drivers in a mega-city. Pearson χ² and logistic regression models were used to analyze the influencing factors for the body regions with a high prevalence. Results The overall prevalence of WMSDs in past 12 months among bus drivers in a mega-city was 49.5% (551/1113). The prevalence of WMSDs by body regions ranged from 4.0% to 38.5%, and led by neck pain (38.5%), lower back pain (25.5%), and shoulder pain (20.8%). The results of logistic regression showed that the risk factors for neck pain were age (>50 years), smoking, tiredness after work (moderate, severe), long sitting (frequently), awkward postures (sometimes, often, frequently), overtime(occasionally, often), workplace temperature (uncomfortable), and noise (severe) (OR=2.014、1.577、2.793、3.025、2.708、2.032、3.406、2.746、1.442、2.998、1.456、3.506；P<0.05); the lower back pain risk factors were current work experience (6-10 years, 11-15 years, and 16-20 years), smoking, tiredness after work (moderate, severe), and awkward postures(sometimes, often, frequently)(OR=1.777、2.130、2.400、1.503、2.951、3.364、1.836、4.569、2.786，P<0.05); and the shoulder pain risk factors were age (46-50 years, and >50 years), smoking, tiredness after work (moderate, severe), vehicle type (hybrid power, diesel oil), awkward postures (often, frequently), overtime (often), and workplace temperature (uncomfortable) (OR=1.737、2.357、1.553、2.259、2.489、1.659、3.295、2.777、3.320、2.266、1.426，P<0.05). Identified protective factors for neck and lower back pain were off-duty physical activity (1-2 times per week, and ≥3 times per week) (OR=0.553、0.470、0.586、0.485，P<0.05). Conclusion Nearly half of the bus drivers in the mega-city report symptoms of WMSDs, mainly in the neck, lower back, and shoulders. The prevalence is related to individual and occupational factors, and prevention and intervention measures should be actively taken.

Objective:To analyze the epidemiological features of respiratory syncytial virus (RSV) infection in Beijing, and monitor the sequence variations in RSV glycoprotein (G) gene and clinical features of infected children.Methods:Respiratory tract specimens were collected from children with acute respiratory infection in the Children′s Hospital Affiliated to Capital Institute of Pediatrics from January 1, 2023 to December 31, 2023. RSV-positive specimens screened by multiple nucleic acid testing were subjected to PCR to amplify the full-length RSV G gene. A phylogenetic tree was constructed after gene sequencing to analyze RSV subtypes and trace G gene variants. Clinical data were retrieved from the medical record system to analyze the clinical features of children with RSV infection in Beijing.Results:A total of 5 489 respiratory specimens were collected from 3 046 male patients and 2 443 female patients. The average age of the patients was 4.36 years. A total of 589 RSV-positive specimens (10.7%, 589/5 489) were detected with 349 from male patients and 240 from female patients. The average age of children with RSV infection was (2.51±2.78) years and the median age was 0.48 years. RSV had been circulating among children in Beijing since March 2023 with two epidemic peaks in May (24.6%, 122/496) and December (18.2%, 126/693). The predominant subtype of RSV in the first half of 2023 was subtype A, but it was replaced by subtype B from November 2023. Phylogenetic analysis revealed a novel G gene of RSV subtype B (RSV-B-BA9-954bp) with a length of 954 bp, which belonged to a new cluster in the phylogenetic tree. The percentage of patients admitted to the Intensive Care Unit (ICU) was higher in children with new variant of RSV subtype B infection than in those with common RSV subtype B infection [44.1% (15/34) vs 25.2% (31/123), χ 2=4.600, P=0.032], while the counts of white blood cells and the levels of C-reactive protein were lower in the children with new variant infection ( P<0.05). Conclusions:RSV has been prevalent among children in Beijing since March 2023 with two epidemic peaks. The predominant A subtype is gradually replaced by to B subtype. A new variant of RSV B G gene (RSV-B-BA9-954bp) is detected among the children.