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*

AIM To investigate effects of petroleum ether fraction from Derris eriocarpa How on glucose and lipid metabolism in a mouse model of metabolic syndrome(MS).METHODS KM mice were fed a high-fat diet and administered streptozotocin intraperitoneally to establish MS models.The MS mice were then randomly assigned to the model group,the metformin hydrochloride group,the lovastatin group,the ursolic acid group,and the high-,medium-and low-dose D.eriocarpa petroleum ether fraction groups,with 10 mice in each group.Ten additional mice maitained on a normal diet served as the normal control group.After 4 weeks of intragastric administration,glucose and lipid metabolism indicators were measured.Hepatic pathological changes were assessed using HE staining and oil red O staining.Liver tissue mRNA expressions of ATF3,PEPCK,FXR,CYP7A1,HNF4ɑ,CYP8B1 and SRB1 were quantified by RT-qPCR.Hepatic protein expressions of ATF3,HNF4ɑ,PEPCK,FXR and CYP7A1 was analyzed by Western blot in MS mice.RESULTS Compared to the model group,the high-dose D.eriocarpa petroleum ether fraction group exhibited significant glucose tolerance improvement(reduced OGTT-AUC,P＜0.01);favorable serum lipid modulation in terms of increased HDL-C levels(P＜0.01)and decreased TG,TC,LDL-C(P＜0.01);reduced renal biomarkers(BUN,SCR)and hepatotoxic indicators of TBA,AST and ALT activities(P＜0.01);alleviated hepatic lipid accumulation and histopathological damage;downregulated mRNA and protein expressions of ATF3,HNF4ɑ and PEPCK,as well as CYP8B1 mRNA expression(P＜0.01);and upregulated mRNA and protein expressions of FXR and CYP7A1,along with SRB1 mRNA expression(P＜0.01).CONCLUSION D.eriocarpa petroleum ether fraction ameliorates glucose and lipid metabolism dysregulation in MS mice by modulating the ATF3/HNF4ɑ/CYP7A1 signaling pathway,consequently eliciting hypoglycemic,hypolipidemic,hepatoprotective and nephroprotective effects.

AIM To investigate effects of petroleum ether fraction from Derris eriocarpa How on glucose and lipid metabolism in a mouse model of metabolic syndrome(MS).METHODS KM mice were fed a high-fat diet and administered streptozotocin intraperitoneally to establish MS models.The MS mice were then randomly assigned to the model group,the metformin hydrochloride group,the lovastatin group,the ursolic acid group,and the high-,medium-and low-dose D.eriocarpa petroleum ether fraction groups,with 10 mice in each group.Ten additional mice maitained on a normal diet served as the normal control group.After 4 weeks of intragastric administration,glucose and lipid metabolism indicators were measured.Hepatic pathological changes were assessed using HE staining and oil red O staining.Liver tissue mRNA expressions of ATF3,PEPCK,FXR,CYP7A1,HNF4ɑ,CYP8B1 and SRB1 were quantified by RT-qPCR.Hepatic protein expressions of ATF3,HNF4ɑ,PEPCK,FXR and CYP7A1 was analyzed by Western blot in MS mice.RESULTS Compared to the model group,the high-dose D.eriocarpa petroleum ether fraction group exhibited significant glucose tolerance improvement(reduced OGTT-AUC,P＜0.01);favorable serum lipid modulation in terms of increased HDL-C levels(P＜0.01)and decreased TG,TC,LDL-C(P＜0.01);reduced renal biomarkers(BUN,SCR)and hepatotoxic indicators of TBA,AST and ALT activities(P＜0.01);alleviated hepatic lipid accumulation and histopathological damage;downregulated mRNA and protein expressions of ATF3,HNF4ɑ and PEPCK,as well as CYP8B1 mRNA expression(P＜0.01);and upregulated mRNA and protein expressions of FXR and CYP7A1,along with SRB1 mRNA expression(P＜0.01).CONCLUSION D.eriocarpa petroleum ether fraction ameliorates glucose and lipid metabolism dysregulation in MS mice by modulating the ATF3/HNF4ɑ/CYP7A1 signaling pathway,consequently eliciting hypoglycemic,hypolipidemic,hepatoprotective and nephroprotective effects.

Facing of mounting resource constraints and rising demands for personalization in medical education,regional anatomy teaching urgently requires transformation.In this paper,we focus on the regional anatomy of the thoracic wall,in order to explore a novel AI-driven teaching paradigm.Anchored in the core principle of"virtual-real integration with cadaveric dissection as the cornerstone,"the paradigm redefines educational objective and constructs an intelligent,closed-loop teaching model integrating students,computers,and instructors.Leveraging the robust support of digital intelligence(e.g.,DeepSeek),this paradigm incorporates interactive method including group collaboration,branching instruction,and gamified assessments.It achieves a comprehensive intelligent transformation of the entire teaching process-from goal setting and plan customization to activity implementation,task completion,outcome exchange,multidimensional evaluation,and reflective iteration.This new paradigm centers on medical students and leverages digital intelligence to activate deep personalized learning potential.It seamlessly integrates fundamental anatomical knowledge with clinical scenarios(e.g.,key anatomy in breast cancer surgery,flap design in breast reconstruction),and significantly enhances clinical decision-making abilities,scientific research and innovative thinking,as well as medical humanistic literacy,paving a new path for intelligent medical education.

Objective To explore the integration value of mobile virtual reality devices in the classroom teaching of human anatomy,and to evaluate their potential impact on the in-depth construction of human anatomy knowledge,the cultivation of spatial cognitive ability,and the transformation of teaching paradigms from the perspectives of cognitive load theory and situated learning.Methods The undergraduate students majoring in clinical medicine in Peking University were selected as the research objects.Among them,students in grade 2019 were the control group,and students in grade 2022 were the experimental group,introducing movable virtual anatomy equipment and other teaching auxiliary method in theory and practice courses.The final exam scores of the two groups of students were compared,and a questionnaire survey was conducted for the experimental group after the course,and the survey result were statistically analyzed.Results The final examination result showed that the average score of the experimental group was 82.47±10.19,and the average score of the control group was 74.82±16.56,which was significantly higher in the experimental group than in the control group,with statistical significance(P＜0.05).The questionnaire survey result showed that compared with traditional classroom teaching,94.62％of students preferred the new auxiliary teaching mode such as VR,96.77％of students believed that VR assisted teaching could achieve the traditional teaching effect or better,95.7％of them think that it improved students' interest in learning human anatomy,and 98.92％thought that it improved students' knowledge of anatomy.Conclusion The application of mobile virtual reality devices in anatomy classroom teaching provides immersive and interactive 3D visualization teaching scenarios,effectively reducing students' cognitive load on abstract and complex anatomical structures,promoting spatial understanding and knowledge internalization,significantly improving teaching effectiveness and self-learning ability,thus changing the traditional anatomy teaching mode and laying a solid foundation for the development of future medical education and the cultivation of medical talents.

Objective To investigate the antibacterial effect and its preliminary mechanism of lavender essential oil on multi-drug resistant Acinetobacter baumannii.Methods Micro-dilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)of lavender essential oil against multi-drug resistant Acinetobacter baumannii,and bactericidal kinetic study was employed to determine the onset and maintenance time of lavender essential oil.Meanwhile,the promoting and therapeutic effects of lavender essential oil on wound healing were observed in a mouse model of infection.Subsequently,crystal violet staining was used to determine the inhibition and clearance of multi-drug resistant Acinetobacter baumannii biofilm by lavender essential oil,and laser confocal microscopy was utilized to observe the survival of bacteria in biofilms.NanoDrop instrument was utilized to quantify the leakage of bacterial DNA nucleic acid and protein after intervention with 3 and 6 mg/mL lavender essential oil,and the leakage of bacterial potassium ion was measured by potassium ion test kit.Proteomics technology combined with bio-informatics were applied to explore the action mechanism of lavender essential oil against multi-drug resistant Acinetobacter baumannii.Results The MIC and MBC of lavender essential oil were both 6 mg/mL,which could kill almost all multi-drug resistant Acinetobacter baumannii at the time point of 120 min,and showed an obvious dose-and time-dependent manner.The overall animal model evaluation showed that both 3 and 6 mg/mL lavender essential oil could promote wound healing,and the curative effect was obvious.Further studies confirmed that 3 mg/mL lavender essential oil had a certain biofilm inhibitory effect on multi-drug resistant Acinetobacter baumannii,and 6 mg/mL also had a certain biofilm clearance effect under the same conditions.Meanwhile,when incubated at 37℃ for 1 h,the dose of 3 mg/mL could increase the leakage of DNA nucleic acid and protein,and significantly promote the efflux of potassium ions.Proteomic analysis suggested that the antibacterial effect of lavender essential oil may be related to affecting the oxidorereductase activity and cell metabolic process of multi-drug resistant Acinetobacter baumannii,and interfering with the biosynthesis of cell wall/membrane/envelope and other structures.Conclusion Lavender essential oil at 3 mg/mL can play an antibacterial effect against multi-drug resistant Acinetobacter baumannii,and its mechanism may be related to the destruction of bacterial biofilm and interference with bacterial metabolism.

Objective To establish an acute exposure model of extreme plateau hypobaric hypoxia environment and explore transcriptomic changes related to learning and memory impairment in rats.Methods Healthy male SD rats aged 6-weeks,200-250 g,were selected and divided into control group and plateau group.The control group was treated with normal pressure and oxygen(19 rats),and the plateau group was placed in a hypobaric hypoxia chamber(19 rats)at a simulated altitude of 8000 meters and treated for 72 hours.Behavioral changes were detected with 16 animals from each group using contextual fear conditioning and Morris water maze(8 rats each).Three hippocampal tissues were extracted from each group for transcriptomic sequencing,and the molecular mechanism of learning and memory impairment induced by extreme plateau environment was analyzed by Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG)and gene set enrichment analysis(GSEA)enrichment.Results The behavioral result showed that compared with the control group,the fear memory and spatial learning memory abilities of rats in plateau group were decreased.GO and KEGG analyses showed that the extreme altitude environment reshaped the hippocampal microenvironment and affected the intercellular signal transmission,while GSEA analysis showed that the extreme altitude environment up-regulated the gene set related to the plasma membrane and extracellular matrix.Conclusion The extreme plateau environment at an altitude of 8000 meters could affect the microenvironment of rat hippocampus,destroy intercellular connections and impair intercellular communication and then induce learning and memory impairment.

Objectives: In order to provide valuable information for the diagnosis and treatment of dermatitis, the prevalence rate and trend changes of common allergens in patients with allergic skin diseases in Beijing City were investigated and analyzed. Methods: This study was a retrospective data collection study. A total of 2 822 patients diagnosed with moderate to severe atopic dermatitis with allergen examinations were collected from Peking University First Hospital from 2017 to 2021, most of them were adults, and 83%(2 340/2 822) were over 18 years old. The ImmunoCAP fluorescent enzyme-linked immunoassay system was used to quantify specific IgE. The positive rate of each allergen was counted according to age, gender and year. The epidemiological characteristics and trends were analyzed. Results: In the past five years, 22 503 allergen-specific IgE test data were collected, and the positive rate of allergens in 40%(1 122/2 822) of the 2 822 patients was mainly multiple sensitization, the positive rate of allergens and multiple sensitization rates were the highest in people aged 13-18 years old. The 2 822 patients were dominated by inhaled allergens, and the highest positive rate was inhaled mixture (29.3%). The top five positive rates of inhaled allergens were Dermatophagoides farina (26.7%), Dermatophagoides pteronyssinus (25.5%), Mugwort (23.9%), Birch pollen (19.2%) and Siberian cocklebur (18.2%). The top five positive rates of food allergens were shrimp (15.2%), peanut (14.8%), sesame (14.7%), wheat (13.2%) and milk (13.1%). Analysis of the positive rate of allergens in different age groups showed except for the positive rate of birch pollen peaked at 3-12 years old, other inhaled allergens were the highest food allergens in 13-18 years old. Among food allergens, the positive rates of fx5, milk, egg and wheat were the highest in <3 years old, the positive rate decreased gradually with age, and the positive rate of other food allergens peaked at 13-18 years old, and the shrimp and crab was the highest in adult. The positive rate of various allergens in the 2 822 patients showed little difference between male and female and the male was slightly higher than female. In the past five years, the positive rate of allergens has been on the rise. The changes of inhaled allergens in cat/dog hair dander, Dermatophagoides farina and cicadas were large, while the positive rate of food allergens was stable. Conclusions: The etiology of the allergic skin diseases is complex, which may be related to allergen exposure, heredity, immunity, environmental factors, abnormal skin barrier function, etc. This study showed the distribution of allergens in patients with allergic skin diseases in Beijing City to a certain extent. It provided epidemiological data and clinical evidence for the prevention and treatment of allergic diseases.
Adult ; Animals ; Dogs ; Humans ; Female ; Male ; Adolescent ; Child, Preschool ; Child ; Allergens ; Dermatitis, Atopic/epidemiology* ; Retrospective Studies ; Hospitals ; Immunoglobulin E

Objective To investigate the Gram-positive coccus resistance in nationwide's tertiary hospitals and understand the trend of antimicrobial resistance.Methods All the clinical isolates were collected from 19 hospitals and the minimal inhibitory concentrations(MICs)were tested using agar/broth dilution method recommended.Results A total of 1 974 pathogenic Gram-positive coccus from 19 tertiary hospitals in 19 cities nationwide over the period from July 2021 to June 2022 were studied.Based on the MIC results,the prevalence of methicillin resistant Stapylococcus aureus(MRSA)and methicillin resistant Stapylococcus epidermidis(MRSE)were 36.4％and 79.9％respectively.No vancomycin insensitivity Staphylococcus was detected.Staphylococcus aureus were 100％susceptibility to linezolid and teicoplanin.Antibiotic resistance rate of Enterococcus faecalis and Enterococcus faecium to ampicillin were 3.1％and 92.9％.The detectation rate of vancomycin resistant Enterococcus(VRE)was 1.6％.Nonsusceptibility rate of Enterococcus faecalis to linezolid was 32.2％,two consecutive monitoring rises and nonsusceptibility rate of Enterococcus faecium(12.5％)was also significantly increased.The prevalence of penicillin non-susceptible Streptococcus pneumoniae(PNSSP)was 0.8％based on non-meningitis and parenteral administration criterion,decrease of nearly 30 percentage points from the previous surveillance.While for cases of oral penicillin,the rate was 71.8％,showing similar to last time.The results indicated that the number of strains with higher MIC value of penicillin(MIC ≥4 mg·L-1)decreased significantly.There were no significant differences of resistance rates of Stapylococcus aureus,Stapylococcus epidermidis,Enterococcus faecalis,Enterococcus faecium and Streptococcus pneumoniae among various groups such as different department,age,or specimen source.Conclusion VRE detection ratio stablized at a relatively low level.The number of Streptococcus pneumoniae with higher MIC value of penicillin decreased significantly compared with the previous monitoring.The increase of linezolidin-insensitive Enterococcus was noteworthy.

Objective To investigate the Gram-negative bacteria resistance in nationwide's tertiary hospitals and understand the trend of antimicrobial resistance.Method All the clinical isolates were collected from 19 hospitals and the minimal inhibitory concentrations(MICs)were tested using agar/broth dilution method recommended.Results A total of 4 066 pathogenic isolates from 19 tertiary hospitals in 19 cities nationwide over the period from July 2021 to June 2022 were studied.Based on the MIC results,Escherichia coli and Klebsiella pneumoniae showed extended spectrum β-lactamase(ESBLs)phenotype rates of 55.0％and 21.0％,respectively,ESBLs phenotype rate of Klebsiella pneumoniae keep going down.The ratios of carbapenems resistance Klebsiella pneumoniae increased by 5 percentage points compared with the previous monitoring.Carbapenems,moxalactam,sitafloxacin,β-lactam combination agents,fosfomycin trometamol,and amikacin displayed desirable antibacterial activity against Enterbacterales,susceptibal rates were above 75％.In addition,tigacycline,omacycline,colistin and fluoxefin maintained good antibacterial activity against their respective effective bacteria/species,and the bacterial sensitivity rates by more than 80％.Resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannnii to imipenem were 26.3％and 72.1％and multidrug-resistant(MDR)detection rates were 41.1％and 77.3％,extensively drug-resistant(XDR)were 12.0％and 71.8％,respectively.Comparison of drug resistance rates from different wards,ages and specimen sources indicated that the proportion of resistance in Klebsiella pneumoniae and Acinetobacter baumannii isolated from intensive care unit(ICU)were significantly higher than non-ICU.Carbapenem resistance rates of Klebsiella pneumoniae isolated from ICU were more than 35％.Resistance rates of Haemophilus influenzae isolated in children to β-lactam,macrolide,clindamycin and ESBLs detection rate in Klebsiella pneumoniae isolated from children were more than those from adults and the old people,so bacterial resistance in children is an important problem in China.Conclusion ESBLs detection rate of Escherichia coli increased slightly after years of continuous decline.The proportion of carbapenem resistant Pseudomonas aeruginosa was stable,but the resistance rate of Klebsiella pneumoniae and Acinetobacter baumannii to carbapenems was still increased,which should be paid more attention.