The construction of a training system for visiting physicians in the department of rare diseases in China is an important measure to improve the overall diagnosis and treatment capacity for rare diseases and address the critical challenge of insufficient knowledge and skills among clinicians in practice. This article systematically describes the visiting physician training system established by the Department of Rare Diseases at Peking Union Medical College Hospital. It summarizes the training objectives and positioning, design logic, and learning modules of the system, aiming to provide a reference for the construction of the specialized talent team for rare diseases in China.

OBJECTIVE To investigate the neuroprotective effect and mechanism of eleutheroside B （ELB） on Parkinson’s disease （PD） model mice by regulating the IκB kinase β （IKKβ）/nuclear factor-κB （NF-κB） signaling pathway. METHODS Fifty mice were randomly divided into normal control group， model group， positive control group （selegiline hydrochloride， 10 mg/kg）， and ELB low-dose and high-dose groups （80， 160 mg/kg）， with 10 mice in each group. Each group was given relevant medicine or normal saline intragastrically for 14 consecutive days. Starting from the 10th day of administration， the model group and all administration groups were intraperitoneally injected with 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine （MPTP） 30 mg/kg， for five consecutive days to establish the chronic PD model. After the last administration for 24 h， six mice were randomly selected from each group to test their behavioral abilities； detect the levels of interleukin-1β （IL-1β）， IL-10， tumor necrosis factor-α （TNF-α） in brain tissue and their mRNA expressions were measured， and positive expression of tyrosine hydroxylase （TH）， protein expressions of TH， α -synuclein （ α -syn）， ionized calcium-binding adaptor molecule 1 （Iba-1）， as well as phosphorylation levels of IKKβ and NF-κB p65 proteins in the brain tissue were detected. The ultrastructure of neurons in substantia nigra was observed. RESULTS Compared with the model group， rotarod endurance time and climbing score of each administration group （except for the ELB low-dose group） were increased significantly （ P ＜0.05）， while the levels and mRNA expressions of IL-1β， TNF-α， α -syn， and Iba-1， as well as phosphorylation levels of IKKβ and NF-κB p65 proteins in brain tissue were decreased significantly （except for TNF-α in the ELB low-dose group）. Conversely， the level and mRNA expression of IL-10 （except for the ELB low-dose group）， TH positive expression and protein expressions were significantly increased （ P ＜0.05）. Typical neurodegenerative pathological changes， such as neuronal karyopyknosis， mitochondrial swelling and vacuolization， and endoplasmic reticulum dilation， all showed varying degrees of improvement. CONCLUSIONS ELB may exert neuroprotective effects by inhibiting the activation of the IKKβ/NF-κB signaling pathway， alleviating inflammatory responses， reducing abnormal α -syn aggregation and neuronal loss， and further improving motor dysfunction in PD mice.

This research investigates the regulatory role of the transcription factor PU.1 in type 1 conventional dendritic cells (cDC1) and its therapeutic potential of modulating the nuclear factor kappaB (NF-κB) cells signaling pathway in non-small cell lung cancer (NSCLC). Utilizing single-cell transcriptome sequencing and comprehensive bioinformatics tools, including the CIBERSORT algorithm, we analyzed the immune cell landscape within NSCLC tissues. Our analysis revealed distinct NSCLC subtypes and delineated the developmental trajectories and functional distinctions of cDC1 cells. Key differentially expressed genes (DEGs) and pivotal functional modules within these cells were identified, highlighting PU.1 as a critical mediator underexpressed in NSCLC samples. Functionally, PU.1 demonstrated the induction of the NF-κB pathway, which led to inhibited tumor proliferation and enhanced activation of cDC1, thereby suggesting its role in tumor immune surveillance. In vivo models confirmed the suppressive effect of PU.1 on NSCLC progression, mediated through its influence on cDC1 functionality via the NF-κB pathway. These findings propose PU.1 as a promising target for NSCLC therapeutic strategies, emphasizing the importance of transcriptional regulators in the tumor microenvironment.

Objective To compare the accuracy of18F-fluorodeoxyglucose(18F-FDG)PET in locating the epileptogenic focus in patients with temporal lobe epilepsy using the single-patient research method based on statistical parametric mapping(SPM)at dif-ferent confidence levels,and to compare it with the asymmetry index(AI)analysis method.Methods A retrospective analysis was conducted on the clinical and imaging data of 86 patients with drug-resistant temporal lobe epilepsy and 37 healthy controls.The pri-mary epileptogenic focus were located by 18F-FDG PET,and two-sample t-test and intracranial asymmetry analysis were performed on individual patients based on SPM.The accuracy of 18F-FDG PET in locating the epileptogenic focus was compared at different confidence levels P＜0.05,P＜0.05[familywise error rate(FWE)corrected],P＜0.01,P＜0.001,respectively.The diagnostic accuracy of the SPM method at the optimal confidence level P value was compared with the AI analysis method,and the data were analyzed using the x2 test.Results The diagnostic accuracy of the two-sample t-test method were 69.77％,79.07％,67.44％ and 63.95％ at confidence levels of P＜0.05,P＜0.05(FWE corrected),P＜0.01 and P＜0.001,respectively;the diagnostic accuracy of the intracranial asymmetry analysis method were 94.19％,81.39％,79.07％,and 75.58％,respectively.There was a statistically significant differ-ence in diagnostic accuracy between the intracranial asymmetry analysis method(P＜0.05)and the two-sample t-test method P＜0.05(FWE corrected)(x2=8.482,P＜0.05);there was also a statistically significant difference in AI analysis method between the two methods(x2=4.793,P＜0.05).Conclusion The intracranial asymmetry analysis method(P＜0.05)based on SPM has a higher accuracy in locating the primary epileptogenic focus in unilateral drug-resistant temporal lobe epilepsy than those in the two-sample t-test method P＜0.05(FWE corrected)and AI analysis method.

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.

[Objective]To clearly identify the difference between rescue injuries and agonal injuries and to avoid duplicate identifications and misidentifications.[Methods]Based on the forensic pathological data of 5 923 cases of death cause identification from 2013 to 2022 in Sun Yat-sen University Forensic Identification Center and Guangzhou Tianhe District Branch of Guangzhou Public Security Bureau,this study retrospectively studied the characteristics of rescue injuries and agonal injuries seen in cause of death identification and their influence on cause of death identification.[Results]Among all the 5 923 cases,640 cases were found to have rescue injuries or agonal injuries,and 624 cases received treatment,of which 609 cases were found to have rescue injuries(97.60%),44 cases were found to have agonal injuries,and 13 cases were found to have both types of injuries.Among the 640 cases,441 were male and 199 were female.The age of death was discontinuously distributed from 0 to 95 years old.The leading cause of death was disease,followed by mechanical injury and asphyxia.The main manifestations of rescue injuries were rib and sternum fractures,soft tissue injuries in the prechest area or face,and pericardial rupture.The most common injuries in agonal stage were falling after unconsciousness,inhalation of foreign body in respiratory tract or multiple violent injuries.Among the 640 cases,19 cases were repeatedly identified,including 15 cases of rescue injuries,6 cases of agonal injuries,and 2 cases of both types of injuries.Compared with the cases where neither type of injuries was detected,the repeated identification rate of treatment injuries and agonal injuries was significantly increased(χ2=4.04,P=0.044;χ2=43.49,P<0.001).Among the 640 cases,11 cases(1.72%)were misidentified as the initial injuries in the first identification,and 13 cases had combined rescue injuries or agonal injuries that were involved in death.[Conclusions]By elucidating the epidemiological characteristics of the two types of injuries,this study proved that the two types of injuries were associated with higher rates of repeated identification and misidentification,which provided a reference for reducing repeated identification and misidentification and improving the accuracy of cause of death identification.

BACKGROUND:Our previous studies found that decreased expression of connexin 43 and its Ser368 phosphorylation after myocardial hypothermic ischemia-reperfusion was closely associated with decreased cardiac conduction velocity and reperfusion arrhythmia.OBJECTIVE:To observe the effect of changes in membrane-type matrix metalloproteinase 2,matrix metalloproteinase 2 and collagen type Ⅳ on the expression of connexin 43 and its Ser368 phosphorylation and electrical conduction in the myocardial extracellular matrix after hypothermic ischemia-reperfusion.METHODS:Sixteen Langendorff extracorporeal cardiac perfusion models were successfully established from SD rats and randomly divided into a control group(n=8)and a hypothermic ischemia-reperfusion group(n=8).The control group was balanced perfused with 37 ℃ Krebs-Henseleit solution for 15 minutes and then continued to be perfused with 37 ℃ Krebs-Henseleit solution for 90 minutes.The hypothermic ischemia-reperfusion group was balanced perfused with 37 ℃ Krebs-Henseleit solution for 15 minutes,and then the heart was arrested for 60 minutes by injection of 4 ℃ Thomas solution.During the cardiac arrest,the periphery was protected by 4 ℃ Krebs-Henseleit solution.Half-volume 4 ℃ Thomas solution was reperfused 30 minutes after the arrest.After stopping the arrest,the heart was reperfused with 37 ℃ Krebs-Henseleit solution for 30 minutes.The occurrence of arrhythmias,rebeating time,and the duration of arrhythmias were recorded from the immediate time point to the end of the reperfusion period.Conduction velocity,absolute inhomogeneity,and inhomogeneity index were measured using the Mapping Lab multi-channel electrophysiological mapping system at the time of balanced perfusion for 15 minutes(T1),reperfusion for 15 minutes/continuous perfusion for 90 minutes(T2),and reperfusion for 30 minutes/continuous perfusion for 105 minutes(T3).The relative expression levels of membrane-type matrix metalloproteinase 2,matrix metalloproteinase 2,collagen type Ⅳ,connexin 43,and its Ser368 phosphorylation in ventricular tissue were detected by western blot assay.RESULTS AND CONCLUSION:(1)No arrhythmia occurred in the control group.There were six cases of arrhythmia in the hypothermic ischemia-reperfusion group during reperfusion.Rebeating time and duration of arrhythmias were(25.38+12.02)and(158.67±67.68)seconds,respectively.(2)The conduction sochronal diagrams at T1,T2,and T3 in the control group were uniform and regular in direction,and the conduction velocity at T2 and T3 was not different from that at T1(P＞0.05).The conduction isochronal diagrams at T2 and T3 in the hypothermic ischemia-reperfusion group were uneven and irregular in direction,and the conduction velocity was slower than that at T1(P＜0.01).The conduction velocity at T2 and T3 in the hypothermic ischemia-reperfusion group was slower than that in the control group(P＜0.01).Conduction dispersion was greater in the hypothermic ischemia-reperfusion group than that in the control group at T2 and T3(P＜0.05).(3)Compared with the control group,the protein expressions of membrane-type matrix metalloproteinase 2 and matrix metalloproteinase 2 in the hypothermic ischemia-reperfusion group were increased(P＜0.05 or P＜0.01),and the protein expression levels of type Ⅳ collagen,connexin 43 and its Ser368 phosphorylation were decreased(P＜0.05 or P＜0.01).(4)The results indicate that after hypothermic ischemia-reperfusion,myocardial extracellular matrix remodeling may mediate the downregulation of myocardial connexin 43 and its Ser368 phosphorylation,slowed conduction velocity and increased conduction dispersion,thereby increasing the risk of arrhythmia.

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.