Objective To analyze the epidemiological characteristics of acute respiratory infections(ARIs)during the autumn-winter season in Beijing,providing evidence for the prevention,control,diagnosis,and treatment of ARIs.Methods A convenience sampling method was employed,enrolling patients who visited Peking Union Medical College Hospital(PUMCH)between September 2023 and February 2024 due to ARIs.Na-sopharyngeal swabs were collected,and real-time fluorescence quantitative PCR was used to detect six common respiratory pathogens[influenza A virus(FluA),influenza B virus(FluB),human rhinovirus(HRV),Myco-plasma pneumoniae(MP),respiratory syncytial virus(RSV),and adenovirus(ADV)],as well as SARS-CoV-2 infection.The distribution patterns of pathogen infections were analyzed.Results A total of 5556 eligible patients were included.The overall positivity rate for the six common respiratory pathogens was 63.7％,with sin-gle-pathogen positivity at 54.0％,dual-pathogen positivity at 8.9％,and triple or more pathogen positivity at 0.7％.The predominant pathogens detected were FluA(16.1％)and RSV(15.7％),followed by ADV(11.1％),MP(11.1％),HRV(10.0％),and FluB(10.0％).No significant difference in overall pathogen positivity was observed between genders.However,significant differences were found between autumn and winter(x2=34.617,P＜0.001)and among pediatric,young/middle-aged,and elderly patients(x2=422.38,P＜0.001).Specifically,MP(x2=8.647,P=0.003),FluA(x2=131.932,P＜0.001),and HRV(x2=174.199,P＜0.001)exhibited significantly higher positivity rates in autumn than in winter,whereas FluB was more prevalent in winter(x2=287.894,P＜0.001).In pediatric patients,MP,RSV,HRV,and ADV positivity rates were significantly higher than in young/middle-aged and elderly patients(all P＜0.001),whereas FluB was more common in young/middle-aged patients(both P＜0.001).The positivity rates of the six common respiratory pathogens significantly declined during the SARS-CoV-2 epidemic period,exhibiting an asynchronous seasonal pattern.Conclusions The prevalence of respiratory pathogens in Beijing is associated with age and season.Tar-geted preventive measures should be implemented in different seasons and for key populations.

Objective To comparatively analyze the quantitative parameters of culprit and non-culprit plaques in patients with acute coronary syndromes(ACS)with a noninvasive technique of coronary computed tomography angiography(CCTA),and to explore the correlation between the quantitative parameters of plaques and culprit plaques.Methods Data were restrospectively collected from 51 ACS patients admitted in some hospital from January to December 2021.The coronary atherosclerotic plaques shown by invasive catheter angiography(ICA)that caused hemodynamic abnormalities and were treated with stenting were defined as offender plaques and enrolled into a culprit plaque group(56 culprit plaques),and other plaques were regarded as non-culprit plaques and divied into a non-culprit plaque group(164 non-culprit plaques).The relationship between culprit plaque and luminal stenosis was analyzed using the chi-square test,and quantitative plaque metrics were compared between the groups.The corelation between quantitative indicators and culprit plaque was analyzed using univariate Logistic regression,and multifactorial Logistic regression analysis was carried out.Statistical analysis was performed with SPSS 23.0 software.Results Analysis of plaque imaging data showed that culprit plaque was significantly associated with the degree of luminal stenosis(P<0.05).Statistically significant differences were found beween the two groups and between the culprit plaques resulting in moderate or greater luminal stenosis and non-culprit plaques in total plaque length,total plaque load,calcification load,fibrolipid volume,fibrolipid load,necrotic core volume and necrotic core load(all P<0.05).Univariate Logistic regression analysis showed total plaque length,total plaque load,fibrolipid volume,fibrolipid load,necrotic core volume and necrotic core load were all significantly correlated with culprit plaques(all P<0.05);multifactorial Logistic regress indicated total plaque length and fibrous lipid load were independent risk factors for culprit plaques,and the probability of culprit plaques increased to 1.093 and 1.101 times for every one unit increase in total plaque length and fibrolipid load,respectively.Conclusion Such quantitative parameters of plaques as total plaque length,total plaque load,fibrolipid volume,fibrolipid load,necrotic core volume and necrotic core load reflects the characteristics of culprit plaques effectively.Quantitative plaque parameter analysis based on CCTA facilitates clinicians for early assessment of patients with coronary atherosclerosis,which enables early intervention and prevention of acute coronary syndromes.[Chinese Medical Equipment Journal,2025,46(6):65-71]

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.

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 analyze the CT manifestations of high altitude pulmonary edema(HAPE)to provide radiological evidence for its early and accurate diagnosis.Methods Totally 200 HAPE patients clinically confirmed at some hospital from April 2021 to April 2024 were enrolled into a study group,and 56 individuals undergoing health examinations at the hospital's physical examination center between January and June 2023 were included into a control group.Examinations were carried out with a United Imaging uCT528 40-slice spiral CT scanner.The patients in the study group were observed in terms of HAPE staging,the extent of pulmonary involvement,CT manifestations of different stages including location,distribution,density and morphology of pulmonary lesion.The diameters of the main pulmonary arteries and ascending aortas of the subjects in the two groups were measured,and the ratios of the two diameters were calculated.SPSS 25.0 software was used for statistical analysis.Results In the study group,there were 26 cases(13.0%)at early stage,105 ones at progression stage(52.5%),32 ones at critical outbreak stage(16.0%)and 37 ones at resolution and absorption stage(18.5%),and there were 35.5%with unilateral lung involvement and 64.5%with bilateral involvement.At early stage,HAPE chest CT manifestations included increased and thickened bilateral bronchovascular bundles,widened main pulmonary artery lumen and faint ground-glass opacity in lungs;at progression stage,HAPE chest CT manifestations revealed multiple cloud-like or patchy areas of increased density within lungs;at critical outbreak stage,CT scanning indicated diffuse patchy opacities and consolidation in lungs,white lung-like changes could be found in some severe cases,and bronchial air signs were shown within affected segments in some ones with severer signs in the right lung than in the left lung;at resolution and absorption stage the CT manifestations were similar to those at early stage,with lesions completely resolving after treatment.The study group had the diameters of the main pulmonary arteries greater while the diameters of the ascending aortas less than those of the control group,and the ratios of the diameters of the two diameters in the study group were higher than those in the control group,with the differences being statistically significant(all P<0.05).Conclusion Chest CT is an important examination method for the early diagnosis of HAPE and clarification of its clinical staging,which directly reflects the pulmonary pathological changes in HAPE patients and helps doctors fully understand the disease progression.

Alzheimer’s disease (AD) is a central neurodegenerative disease characterized by progressive cognitive decline and memory impairment in clinical. Currently, there are no effective treatments for AD. In recent years, a variety of therapeutic approaches from different perspectives have been explored to treat AD. Although the drug therapies targeted at the clearance of amyloid β-protein (Aβ) had made a breakthrough in clinical trials, there were associated with adverse events. Neuroinflammation plays a crucial role in the onset and progression of AD. Continuous neuroinflammatory was considered to be the third major pathological feature of AD, which could promote the formation of extracellular amyloid plaques and intracellular neurofibrillary tangles. At the same time, these toxic substances could accelerate the development of neuroinflammation, form a vicious cycle, and exacerbate disease progression. Reducing neuroinflammation could break the feedback loop pattern between neuroinflammation, Aβ plaque deposition and Tau tangles, which might be an effective therapeutic strategy for treating AD. Traditional Chinese herbs such as Polygonum multiflorum and Curcuma were utilized in the treatment of AD due to their ability to mitigate neuroinflammation. Non-steroidal anti-inflammatory drugs such as ibuprofen and indomethacin had been shown to reduce the level of inflammasomes in the body, and taking these drugs was associated with a low incidence of AD. Biosynthetic nanomaterials loaded with oxytocin were demonstrated to have the capability to anti-inflammatory and penetrate the blood-brain barrier effectively, and they played an anti-inflammatory role via sustained-releasing oxytocin in the brain. Transplantation of mesenchymal stem cells could reduce neuroinflammation and inhibit the activation of microglia. The secretion of mesenchymal stem cells could not only improve neuroinflammation, but also exert a multi-target comprehensive therapeutic effect, making it potentially more suitable for the treatment of AD. Enhancing the level of TREM2 in microglial cells using gene editing technologies, or application of TREM2 antibodies such as Ab-T1, hT2AB could improve microglial cell function and reduce the level of neuroinflammation, which might be a potential treatment for AD. Probiotic therapy, fecal flora transplantation, antibiotic therapy, and dietary intervention could reshape the composition of the gut microbiota and alleviate neuroinflammation through the gut-brain axis. However, the drugs of sodium oligomannose remain controversial. Both exercise intervention and electromagnetic intervention had the potential to attenuate neuroinflammation, thereby delaying AD process. This article focuses on the role of drug therapy, gene therapy, stem cell therapy, gut microbiota therapy, exercise intervention, and brain stimulation in improving neuroinflammation in recent years, aiming to provide a novel insight for the treatment of AD by intervening neuroinflammation in the future.

Objective To investigate the in vitro anti-hepatitis B virus(HBV)effects of icariside Ⅱ(ICS Ⅱ)and its impact on mitochondrial fission.Methods HBV-positive hepatocellular carcinoma HepAD38 cells were used as the cellular model.The cytotoxicity of ICS Ⅱ was assessed via CCK8 assay.The secretion levels of HBV surface antigen(HBsAg)and HBV e antigen(HBeAg),as well as HBV DNA copy numbers,were measured by ELISA and qPCR after treatment with ICS Ⅱ alone or ICS Ⅱ in combination with entecavir(ENT).The effects of ICS Ⅱ on mitochondrial morphology and motility were observed using confocal laser scanning microscopy and transmission electron microscopy(TEM).After ICS Ⅱ treatment,Western blot was performed to analyze the expression levels of key proteins involved in mitochondrial dynamics.Additionally,intracellular reactive oxygen species(ROS)production was evaluated via fluorescence staining.Results The CCK8 assay results showed that ICS Ⅱ treatment at 25 μmol/L had no significant effect on cell proliferation after 72 h.ICS Ⅱ significantly inhibited the secretion levels of HBsAg and HBeAg,with the respective inhibition rates reaching 54.90％and 39.65％(P＜0.05).Additionally,ICS Ⅱ alone reduced HBV DNA copy numbers by 15.19％,while ENT alone achieved a 34.11％inhibition rate.Notably,ICS Ⅱ in combination with ENT reduced HBV DNA copy numbers by 55.81％(P＜0.05).Furthermore,ICS Ⅱ induced mitochondrial shortening and enhanced mitochondrial motility in HepAD38 cells(P＜0.05).ICS Ⅱ significantly increased the expression levels of mitochondrial motility-related proteins,including Mfn1,Fis1,and phosphorylated Drp1(ser 616)(P＜0.05),while no significant changes were observed in the expression levels of Mfn2,total Drp1,or Drp1(ser 637)(P＞0.05).Additionally,ICS Ⅱ significantly suppressed the production of intracellular ROS in HepAD38 cells(P＜0.05).Conclusion ICS Ⅱ inhibits HBV replication in HepAD38 cells,and the underlying mechanism may be associated with the promotion of mitochondrial fission and suppression of ROS production.

[Objective]To explore the cultivation mode of innovative capacity of medical students in"curriculum-project-competition Continuity System",in order to cultivate high-quality medical talents with innovative thinking and strong practical capacity.[Methods]Taking the courses of Biochemistry and its related courses Medical Molecular Biology and Biochemistry Experiment for clinical medicine majors as a pilot,this research explores the training mode for innovative capabilities of medical talents in the new era by constructing a theoretical teaching system covering"basic theories,cutting-edge science and technology,and innovative thinking",adding innovative experiments featuring"independent topic selection,innovative design and cooperative discussion",and reforming the traditional project-competition mode.[Results]Through reform practices,the students'subjectivity in learning has been effectively strengthened,their awareness of independent innovation and exploration has been significantly stimulated,and their abilities to independently analyze and solve complex problems,as well as comprehensive innovative capabilities such as teamwork and interdisciplinary integration,have been systematically cultivated.The mastery rate of core knowledge in Biochemistry among the medical students of our university in the National Medical Licensing Examination has been continuously improving.Under the guidance of the teaching team,undergraduate students majoring in clinical medicine have been approved for multiple national/provincial college students'innovative training projects and"Xinmiao Program",published several SCI papers,and won various national/provincial science and technology competition awards.The quality of innovative talent training has achieved substantial improvement.[Conclusion]The"curriculum-project-competition continuity system"can effectively help students consolidate the foundation and promote the cultivation of students'innovation ability,providing an effective reference basis for the cultivation of innovative capacity of clinical medicine professionals in medical colleges and universities.