Objective To explore the time cross-lagged effect between carotid intima-media thickness(CIMT)and bone mineral density(BMD)and to assess whether CIMT can be used as an early predictor of osteoporosis.Methods Based on the retrospective cohort study involved,people who underwent health checkups at The First Affiliated Hospital of Xi'an Jiaotong University from January 2019 to December 2023 were selected,and data related to CIMT and BMD were collected.The time-series relationship between CIMT and BMD was explored by cross-lagged modeling.Meanwhile,the effects of CIMT on BMD and its dose-response relationship were assessed using multiple linear regression and restricted cubic spline regression models.Results Analysis of 2 453 study subjects revealed a significant negative relationship between prior physical examination CIMT and subsequent BMD,and this relationship remained significant after controlling for confounders.For every 1-unit increase in CIMT,there was a mean decrease in second-stage BMD T-values of 0.113.Restricted cubic spline regression analysis showed a maximum decrease in BMD T-values of 0.121 for every 1.00 mm increase in CIMT.Conclusion The present study found that there was a significant negative cross-lag effect between CIMT and BMD,and that there was a dose-response between an increase in CIMT and a decrease in BMD.CIMT,as an easy-to-measure indicator,may be a potential marker for early prediction of osteoporosis,especially in the elderly population.

Objective:To investigate levels of endothelin-1(ET-1)and Apclin in patients with hypertrophic car-diomyopathy(HCM)and diagnostic value of their combination with ECG for HCM,and their association with prognosis.Methods:A total of 150 HCM patients admitted in the Second Affiliated Hospital of Xi'an Medical Uni-versity between June 2020 and June 2022 were selected as observation group.According to death during follow-up,the observation group was divided into survival group(n=64)and death group(n=86),and another 100 healthy volunteers who underwent physical examination in our hospital simultaneously were selected as control group.ET-1,Apelin and ECG indexes were compared between above-mentioned groups.Diagnostic value of ET-1,Apelin and ECG combined detection for HCM was analyzed by receiver operating characteristic(ROC)curve.Multivariate Logistic regression was used to analyze influencing factors of death within 6-month follow-up in HCM patients,and nomogram model was established.Results:Compared with participants in control group,those in the observa-tion group had significant higher ET-1[(0.64±0.15)pmol/L vs.(0.39±0.07)pmol/L],QRS wave group(∑QRS)[(23.60±3.96)mm vs.(14.02±1.78)mm],Cornell voltage index(SV3+RaVL)[(2.12±0.40)mV vs.(1.05±0.20)mV]and S-wave on V1 lead+R-wave on V5 lead(SV1+RV5)[(3.88±0.73)mV vs.(2.24±0.34)mV],and significant lower Apelin[(1.10±0.25)pg/ml vs.(1.58±0.17)pg/ml]level(P＜0.001 all).ROC curve indicated that the area under the curve(AUC)of combined detection of above five indexes diagno-sing HCM was 0.933(95％CI 0.895～0.961),significantly higher than any single detection(Z=3.681～6.428,P＜0.001 all),the H-L goodness of fit test showed P=0.056,suggesting that the model was well accepted,and DCA showed that ET-1 and Apelin combined ECG detection model had good clinical application value in HCM.Multivariate Logistic regression indicated that ET-1,∑QRS,SV3+RaV and SV1+RV5 were independent risk factors for death within 6-month in HCM patients(OR=2.617～3.600,P＜0.001 all),and Apelin was its inde-pendent protective factor(OR=0.271,P＜0.001).The nomogram model of HCM patients dying within 6 months was 4.627+0.452 × ET-1+0.536 × Apelin+0.575 × ∑QRS+0.541 × SV3+RaVL+0.352 × SV1+RV5.Conclusion:Serum ET-1 and Apelin levels significantly change in HCM patients,and the combination of ECG detection and both indexes have good performance diagnosing HCM and are independent influential factors for the death of HCM patients within 6 months.

Objective To explore the time cross-lagged effect between carotid intima-media thickness(CIMT)and bone mineral density(BMD)and to assess whether CIMT can be used as an early predictor of osteoporosis.Methods Based on the retrospective cohort study involved,people who underwent health checkups at The First Affiliated Hospital of Xi'an Jiaotong University from January 2019 to December 2023 were selected,and data related to CIMT and BMD were collected.The time-series relationship between CIMT and BMD was explored by cross-lagged modeling.Meanwhile,the effects of CIMT on BMD and its dose-response relationship were assessed using multiple linear regression and restricted cubic spline regression models.Results Analysis of 2 453 study subjects revealed a significant negative relationship between prior physical examination CIMT and subsequent BMD,and this relationship remained significant after controlling for confounders.For every 1-unit increase in CIMT,there was a mean decrease in second-stage BMD T-values of 0.113.Restricted cubic spline regression analysis showed a maximum decrease in BMD T-values of 0.121 for every 1.00 mm increase in CIMT.Conclusion The present study found that there was a significant negative cross-lag effect between CIMT and BMD,and that there was a dose-response between an increase in CIMT and a decrease in BMD.CIMT,as an easy-to-measure indicator,may be a potential marker for early prediction of osteoporosis,especially in the elderly population.

Objective:To develop a 3D-printed extraocular muscle teaching model and evaluate its teaching effect and learning experience among residents in standardized training.Methods:A total of 24 residents in standardized training who entered the Department of Ophthalmology, Peking Union Medical College Hospital from 2022 to 2024 were included, with 10, 7, and 7 residents in the first, second, and third grades, respectively. A simulated orbit and movable eyeball were constructed based on 3D printing technology. Tractionable elastic silicone bands were arranged on it to simulate healthy extraocular muscles, and non-elastic ropes were used to simulate diseased extraocular muscles. The model was applied in teaching rounds. Before and after the rounds, the residents were tested on basic knowledge (including diagnosis and judgment of surgical indications, with a full score of 40) and core knowledge (including judgment of mainly involved extraocular muscles and surgical design, with a full score of 60). Pearson correlation analysis was used to evaluate the correlation between the residents′ grades and their scores before the rounds, scores after the rounds, and score increments. A questionnaire survey (full score of 100) was conducted to assess their learning experience.Results:Before the teaching rounds, the average basic knowledge score of all residents was (21.0±7.5) and the core knowledge score was (11.3±7.7). These scores were positively correlated with the residents′ grades ( r=0.74, 0.69, all P<0.001) but generally low. After the teaching rounds, the basic knowledge score increased to (31.7±4.6), and the core knowledge score increased significantly to (48.5±3.8). There were no statistically significant differences in these scores among different grades ( P=0.22, P=0.83). The increments of basic knowledge and core knowledge scores decreased with the increase of residents′ grades, with statistically significant correlations ( r=-0.60, -0.65; P=0.002, P=0.001). The average scores of all residents in appearance, convenience, effectiveness, and total score were (18.2±1.1), (26.6±2.2), (40.0±4.0), and (84.8±5.0), respectively. There was no statistically significant correlation between these scores and the residents′ grades ( P=0.24, P=0.84, P=0.25, P=0.58). Suggestions for improving the current teaching model included: increasing the model size for long-distance viewing; enhancing the adhesion between silicone bands (simulating eye muscles) and the simulated eyeball; reducing the friction between the inner sphere and outer shell of the simulated eyeball to improve the model′s maneuverability and flexibility. Conclusions:The 3D-printed extraocular muscle teaching model can help residents of all grades quickly master the key and difficult points in learning restrictive strabismus caused by thyroid-associated ophthalmopathy. In clinical teaching of complex ocular diseases related to systemic diseases, constructing physical teaching models can effectively improve teaching effects and students′ learning experience.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective:To explore the impact of the two-way referral model on compliance and prognosis in patients with heart failure.Methods:This bidirectional cohort study enrolled chronic heart failure (CHF) patients treated at Qilu Hospital of Shandong University or designated primary hospitals between March 2018 and March 2022. Patients were categorized into two groups based on referral status: two-way referral group (participating in the referral model with≥1 follow-up visit at primary hospitals) and the core hospital group (receiving treatment and follow-up exclusively at Qilu Hospital). Baseline clinical characteristics were collected and compared between groups. Patients underwent followed-up, with primary endpoints including follow-up rate, drug (β-blockers, angiotension converting enzyme inhibitor (ACEI)/angiotensin Ⅱ receptor blockers (ARB)/angiotensin receptor-neprilysin inhibitor (ARNI), sodium-glucose cotransporter 2 inhibitors and mineralocorticoid receptor antagonists) utilization rate and target dose achievement rate. Secondary endpoints encompassed changes from baseline in left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDd), and N-terminal pro-brain natriuretic peptide (NT-proBNP), plus cardiovascular mortality and heart failure rehospitalization. Generalized linear mixed models analyzed longitudinal trends in LVEF, LVEDd, and NT-proBNP levels. Kaplan-Meier curves and Cox regression evaluated LVEF recovery rates, supplemented by subgroup analyses. Multivariate logistic regression was used to identify factors influencing target dose achievement rate for β-blockers and ACEI/ARB/ARNI therapies in CHF patients.Results:A total of 357 patients were enrolled, aged 53 (41, 63) years, including 256 males (71.7%). 157 patients were in the two-way referral group and 200 patients in the core hospital-treated group. Compared with the core hospital-treated group, the two-way referral group had lower baseline LVEF (28 (22, 34)% vs. 31 (23, 36)%, P=0.021) and systolic blood pressure (116 (104, 125) mmHg vs. 121 (109, 134) mmHg (1 mmHg=0.133 kPa), P=0.010). The 12-month follow-up rate of the two-way referral group was higher than the core hospital-treated group (73.8% vs. 56.0%, P=0.004). No significant between-group differences were observed in drug utilization rate of β-blockers, ACEI/ARB/ARNI, or sodium-glucose cotransporter 2 inhibitors during follow-up (all P>0.05), while mineralocorticoid receptor antagonists use showed a declining trend in both groups. Although the core hospital-treated group had higher target dose achievement rates for β-blockers (65.4% vs. 49.3%, P=0.042) and ACEI/ARB/ARNI (79.8% vs. 65.8%, P=0.046) than the two-way referral group, multivariate logistic regression indicated that the two-way referral model was not a negative predictor for these outcomes (all P>0.05). Both groups showed improved NT-proBNP, LVEDd, and LVEF from baseline (all P<0.001) with no significant difference in trends between groups (all P>0.05). There was no significant difference in the composite incidence (7.6% vs. 6.5%, P=0.674) and cumulative incidence (log-rank P=0.684) of cardiovascular death and heart failure rehospitalization at 12 months between two groups. Conclusion:The two-way referral model demonstrates advantages in improving medication adherence, drug utilization rates, and targetdoseachievement rates among CHF patients. This model not only promotes cardiac functional recovery but also reduces risks of cardiovascular mortality and heart failure rehospitalization, achieving comparable therapeutic and management outcomes to those observed in core hospital-treated patients.

Objective:To investigate levels of endothelin-1(ET-1)and Apclin in patients with hypertrophic car-diomyopathy(HCM)and diagnostic value of their combination with ECG for HCM,and their association with prognosis.Methods:A total of 150 HCM patients admitted in the Second Affiliated Hospital of Xi'an Medical Uni-versity between June 2020 and June 2022 were selected as observation group.According to death during follow-up,the observation group was divided into survival group(n=64)and death group(n=86),and another 100 healthy volunteers who underwent physical examination in our hospital simultaneously were selected as control group.ET-1,Apelin and ECG indexes were compared between above-mentioned groups.Diagnostic value of ET-1,Apelin and ECG combined detection for HCM was analyzed by receiver operating characteristic(ROC)curve.Multivariate Logistic regression was used to analyze influencing factors of death within 6-month follow-up in HCM patients,and nomogram model was established.Results:Compared with participants in control group,those in the observa-tion group had significant higher ET-1[(0.64±0.15)pmol/L vs.(0.39±0.07)pmol/L],QRS wave group(∑QRS)[(23.60±3.96)mm vs.(14.02±1.78)mm],Cornell voltage index(SV3+RaVL)[(2.12±0.40)mV vs.(1.05±0.20)mV]and S-wave on V1 lead+R-wave on V5 lead(SV1+RV5)[(3.88±0.73)mV vs.(2.24±0.34)mV],and significant lower Apelin[(1.10±0.25)pg/ml vs.(1.58±0.17)pg/ml]level(P＜0.001 all).ROC curve indicated that the area under the curve(AUC)of combined detection of above five indexes diagno-sing HCM was 0.933(95％CI 0.895～0.961),significantly higher than any single detection(Z=3.681～6.428,P＜0.001 all),the H-L goodness of fit test showed P=0.056,suggesting that the model was well accepted,and DCA showed that ET-1 and Apelin combined ECG detection model had good clinical application value in HCM.Multivariate Logistic regression indicated that ET-1,∑QRS,SV3+RaV and SV1+RV5 were independent risk factors for death within 6-month in HCM patients(OR=2.617～3.600,P＜0.001 all),and Apelin was its inde-pendent protective factor(OR=0.271,P＜0.001).The nomogram model of HCM patients dying within 6 months was 4.627+0.452 × ET-1+0.536 × Apelin+0.575 × ∑QRS+0.541 × SV3+RaVL+0.352 × SV1+RV5.Conclusion:Serum ET-1 and Apelin levels significantly change in HCM patients,and the combination of ECG detection and both indexes have good performance diagnosing HCM and are independent influential factors for the death of HCM patients within 6 months.

Objective To understand the epidemiological characteristics of road traffic accident injuries in Beijing can provide a theoretical basis for improving the pre-hospital emergency service capabilities and levels,and increasing patient survival rates while reducing disability,mortality rates.Methods A retrospective analysis was conducted on the medical records of 9207 patients who made pre-hospital emergency calls due to road traffic accident injuries at the Beijing Emergency Medical Center in 2023 to understand the patients' age,gender,injury time,injury location,injury degree and other characteristics.Results Traumatic diseases ranked first in the classification of emergency medical conditions in Beijing.Among them,road traffic accidents account for 37％.The ratio of male to female patients was 1.32∶1.The largest number of patients were aged 31-40,accounting for nearly 25％.The proportion of underage patients and those aged 71 and above was 12.16％.The differences in gender and age distribution were statistically significant,while the differences in gender distribution among different age groups were not statistically significant.Road traffic accident injuries occured most frequently in September and least in January.There were more cases in summer and autumn,and fewer in winter and spring.The most common injury sites in road traffic accidents were limbs/skin and head and neck,accounting for 81.06％.The patients with moderate severity of injuries were the most numerous,accounting for 85.29％.Conclusion To avoid road traffic accidents,prevention should be the priority.It is necessary to strengthen the joint governance of multiple departments and minimize the occurrence of road traffic accident from the source.Pre-hospital emergency care must focus on key populations and key seasons,strengthen professional skills training and resource allocation,ensure efficient and smooth connection between pre-hospital and in-hospital care.Popularize and publicize the importance of self-rescue and mutual rescue,promote first aid knowledge and skills training for the public,and create a social atmosphere where"rescue is right beside us".