Background: Aspiration pneumonia (AP), which can be caused by gastric content inhalation into the lower airways, causes acute lung injury (ALI) through complex mechanisms, including inflammation, oxidative stress, and apoptosis. Here, we evaluated the efficacy of exosomes derived from human placental mesenchymal stem cells (hpMSCs) in mitigating ALI in a murine model of AP. We also investigated the role of hsa-let-7i-5p, the most abundant miRNA in hpMSC-derived exosomes, in this respect. Methods: Adult male C57BL/6 mouse AP models were administered hpMSC-derived exosomes (APExo group) or phosphate-buffered saline (AP group) intra-tracheally. After 48 h, the mice were euthanized and evaluated. The effects of hsa-let-7i-5p were assessed by specific inhibition or overexpression. Results: Compared with the APExo group, the AP group exhibited significantly greater ALI, as evidenced by histological damage, increased lung injury scores, impaired lung function, increased leukocyte infiltration, and elevated tissue edema (all P < 0.05). The untreated AP group also showed more inflammation, characterized by nuclear factor-κB upregulation, macrophage M1 polarization, and cytokine level elevation (tumor necrosis factor-α, interleukin-1β, and interleukin-6), as well as increased oxidation and activation of the apoptosis pathway (all P < 0.05). Notably, the therapeutic effects of hpMSC-derived exosomes were compromised by specific inhibition of hsa-let-7i-5p. Furthermore, engineered exosomes derived from genetically modified RAW264.7 overexpressing hsa-let-7i-5p demonstrated therapeutic effects against AP similar to those obtained with hpMSC-derived exosomes. Conclusions In a murine AP model, intra-tracheal administration of hpMSC-derived exosomes has ALI-mitigating effects, involving inflammation, oxidation, and apoptosis modulation, with hsa-let-7i-5p playing a pivotal mediating role.

Objective: Machine learning (ML) has been reported to have better predictive capability than traditional statistical techniques. The aim of this study was to assess the efficacy of ML algorithms and logistic regression (LR) for predicting depressive symptoms during the COVID-19 pandemic. Methods: Analyses were carried out in a national cross-sectional study involving 21,916 participants. The ML algorithms in this study included random forest (RF), support vector machine (SVM), neural network (NN), and gradient boosting machine (GBM) methods. The performance indices were sensitivity, specificity, accuracy, precision, F1-score, and area under the receiver operating characteristic curve (AUC). Results: LR and NN had the best performance in terms of AUCs. The risk of overfitting was found to be negligible for most ML models except for RF, and GBM obtained the highest sensitivity, specificity, accuracy, precision, and F1-score. Therefore, LR, NN, and GBM models ranked among the best models. Conclusion Compared with ML models, LR model performed comparably to ML models in predicting depressive symptoms and identifying potential risk factors while also exhibiting a lower risk of overfitting.

OBJECTIVE: High-altitude hypoxia exposure often damages hippocampus-dependent learning and memory. Nogo-A is an important axonal growth inhibitory factor. However, its function in high-altitude hypoxia and its mechanism of action remain unclear. METHODS: In an in vivo study, a low-pressure oxygen chamber was used to simulate high-altitude hypoxia, and genetic or pharmacological intervention was used to block the Nogo-A/NgR1 signaling pathway. Contextual fear conditioning and Morris water maze behavioral tests were used to assess learning and memory in rats, and synaptic damage in the hippocampus and changes in oxidative stress levels were observed. In vitro, SH-SY5Y cells were used to assess oxidative stress and mitochondrial function with or without Nogo-A knockdown in Oxygen Glucose-Deprivation/Reperfusion (OGD/R) models. RESULTS: Exposure to acute high-altitude hypoxia for 3 or 7 days impaired learning and memory in rats, triggered oxidative stress in the hippocampal tissue, and reduced the dendritic spine density of hippocampal neurons. Blocking the Nogo-A/NgR1 pathway ameliorated oxidative stress, synaptic damage, and the learning and memory impairment induced by high-altitude exposure. CONCLUSION: Our results demonstrate the detrimental role of Nogo-A protein in mediating learning and memory impairment under high-altitude hypoxia and suggest the potential of the Nogo-A/NgR1 signaling pathway as a crucial therapeutic target for alleviating learning and memory dysfunction induced by high-altitude exposure. GRAPHICAL ABSTRACT available in www.besjournal.com.
Animals ; Oxidative Stress ; Hippocampus/metabolism* ; Rats ; Nogo Proteins/genetics* ; Male ; Rats, Sprague-Dawley ; Hypoxia/metabolism* ; Altitude ; Synapses ; Humans ; Altitude Sickness/metabolism*

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To investigate the one-year postpartum weight retention for patients with gestational diabetes mellitus(GDM)and analyze its related influencing factors,so as to improve the postpartum weight retention.Methods GDM women who were diagnosed and gave birth at the Obstetrics and Gynecology Hospital,Fudan University from Oct 2022 to May 2023 were selected as the research subjects.The GDM postpartum weight status survey questionnaire was used to conduct a survey of one-year postpartum weight retention status and analyze relevant influencing factors.Results A total of 150 GDM postpartum women were included,with a weight retention rate of 46.7%one year after delivery,including a high weight retention rate of 25.3%.The follow-up rate of postpartum glucose tolerance was 36.0%,and the influencing factors of postpartum weight retention were excessive gestational weight gain(OR=2.883,95%CI:1.226-6.779)and the presence of dietary risk(OR=4.604,95%CI:1.065-19.903).Conclusion The one-year postpartum weight retention after GDM is relatively high.The possible influencing factors are excessive weight gain during pregnancy and dietary risk after delivery.Attention should be paid to the weight and healthy diet management of GDM during pregnancy and postpartum from multiple dimensions.

With the rapid development of generative artificial intelligence(GAI)technologies,their widespread application in academic research and writing is continuously expanding the boundaries of sci-entific inquiry.However,this trend has also raised a series of ethical and regulatory challenges,inclu-ding issues related to authorship,content authenticity,citation accuracy,and accountability.In light of the growing involvement of AI in generating academic content,establishing an open,controllable,and trustworthy ethical governance framework has become a key task for safeguarding research integrity and maintaining trust within the academic community.This expert consensus outlines ethical requirements across key stages of AI-assisted academic writing-including topic selection,data management,citation practices,and authorship attribution.It aims to clarify the boundaries and ethical obligations surrounding AI use in academic writing,ensuring that technological tools enhance efficiency without compromising in-tegrity.The goal is to provide guidance and institutional support for building a responsible and sustainable research ecosystem.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

AIM To investigate the protective effects of the aqueous extract of Bulbophyllum kwangtungense Schltr.on D-galactose(D-gal),an oxidative stress-induced liver damage in rats.METHODS 60 Male SD rats were randomly divided into the normal control group,the model group,the resveratrol group(20 mg/kg),and low-dose,medium-dose,and high-dose B.kwangtungense aqueous extract groups(750,1 500 and 3 000 mg/kg).Except for those of the normal control group,the rats of the other groups were subcutaneously injected with D-gal(200 mg/kg)in the back of neck to establish a liver damage model.Simultaneously,each group underwent the corresponding drug administration by gavage(10 mL/kg)once daily for 42 days.After the treatment period,the rats had their peripheral blood and liver tissues collected for the calculation of the liver index;their serum AST and ALT activities,hepatic SOD and GSH-Px activities,and MDA levels measured;their hepatic pathological changes observed using HE staining;their hepatic mRNA expressions of Nrf2,NQO-1 and HO-1 detected by RT-qPCR;and their hepatic protein expressions of Nrf2,NQO-1,HO-1,Bax,Bcl-2 and cleaved Caspase-3 measured by Western blot.RESULTS Compared with the model group,the groups intervened with medium-dose or high-dose B.kwangtungense aqueous extract showed increased liver index level(P＜0.01);decreased serum AST and ALT activities(P＜0.01);increased hepatic SOD and GSH-Px activities(P＜0.05,P＜0.01);reduced MDA levels(P＜0.01);alleviated pathological liver damage and increased hepatic mRNA and protein expressions of Nrf2,NQO-1 and HO-1(P＜0.05,P＜0.01);and reduced protein expressions of cleaved Caspase-3 and the Bax/Bcl-2 ratio as well(P＜0.05,P＜0.01).CONCLUSION The aqueous extract of B.kwangtungense is protective of rats with D-gal-induced liver injury,and the underlying mechanism may associate with the inhibition of oxidative stress and the suppression of hepatocellular apoptosis mediated by the activation of the Nrf2/HO-1/NQO-1 signaling pathway.

AIM To study the protective effect of Gynura divaricate polysaccharide on gouty nephropathy(GN)induced by dry yeast combined with adenine in rats.METHODS Sixty male SD rats were randomly divided into the normal group,the model group,the allopurinol group(42 mg/kg),and the low-dose,medium-dose and high-dose G.divaricate polysaccharide groups(140,280,560 mg/kg).All the rats except those of the normal group were induced into GN models by intragastrical dosing of yeast(5 g/kg)and adenine(100 mg/kg)and intervened with corresponding drug administration simultaneously.After 35 days,the rats had their levels of creatinine(Cr)and uric acid(UA)in serum and urine detected and their fraction excretion of uric acid(FEUA)value determined;their kidney mass and volume measured and their levels of kidney index and density calculated;their renal pathological changes checked by HE staining;their renal GLUT9,URAT1,ABCG2 and OAT1 mRNA expressions dectected by RT-qPCR;and their renal GLUT9,URAT1,ABCG2 and OAT1 protein expressions dectected by Western blot.RESULTS Compared with the model group,each dose of G.divaricate polysaccharide group displayed decreased levels of kidney mass,kidney volume and kidney index(P＜0.01);increased levels of kidney density(P＜0.05,P＜0.01);decreased serum levels of UA and Cr(P＜0.01);increased urine levels of UA and Cr(P＜0.01);increased FEUA value(P＜0.01);decreased GLUT9,URAT1 mRNA and protein expressions(P＜0.05,P＜0.01);and increased ABCG2,OAT1 mRNA and protein expressions(P＜0.05,P＜0.01);and more alleviated renal histological aberrations.CONCLUSION G.divaricate polysaccharide exerts good protective effects against yeast/adenine-induced GN in rats probably through down-regulating protein expression of GLUT9,URAT1 and up-regulating ABCG2 and OAT1.