Objective To analyze the types and distribution of microbiome in intestinal and lung tissues of children with asthma, and to explore the correlation between microbiota changes and asthma. Methods From 2021 to 2023, a total of 28,939 children with asthma who visited Ezhou Central Hospital, Maternal and Child Health Hospital or Ezhou Egang Hospital were selected as the study subjects, and 2,000 healthy children who underwent outpatient physical examinations at these three hospitals during the same period were selected as the control group. The distribution and characteristics of intestinal and pulmonary microbiome in the two groups were analyzed by 16SrDNA sequencing. Logistic regression analysis model was used to analyze the correlation between microbiota distribution and asthma occurrence. Results In the intestinal tissues of children with asthma compared to healthy children, the abundance of Bacteroidetes at the phylum level decreased, while the abundance of Firmicutes and Proteobacteria increased significantly (P<0.05), and the abundance of Prevotalle and Clostridium at the genus level increased significantly. In lung tissues of asthmatic children compared to health children, the abundance of Firmicutes at the phylum level decreased while the abundance of Proteobacteria increased significantly (P<0.05), and the abundance of Neisseria, Prevotella and Actinomyces at the genus level increased significantly. Binary logistic regression results showed that the abundances of Lactobacillus (OR=0.842, 95% CI: 0.533-0.947), Bacteroides fragilis (OR=0.649, 95%CI: 0.377-0.890), Bifidobacterium (OR=0.901, 95% CI: 0.633-0.994), and Parabacteroides distasonis (OR=0.547, 95% CI: 0.192-0.708) in the intestinal tissues were all protective factors for the asthma in children. In the lung tissue, the abundance of Neisseria (OR=2.140, 95% CI: 1.749-3.305) was a risk factor for the asthma in children, and Prevotella (OR=0.691, 95% CI: 0.491-0.926) was a protective factor for the asthma in children (P<0.05). Conclusion The dysbiosis of intestinal and pulmonary microbiome is closely related to the occurrence of asthma in children, and the detection of microbiota is of great significance for the diagnosis of childhood asthma.

Polymyxins,a class of cyclic peptide antibiotics,have become the last line of defense against gram-negative bacterial infections as the number of multidrug-resistant bacteria continues to rise.Het-eroresistance refers to the presence of subpopulations within the same strain with varying sensitivities to antibi-otics,which cannot be detected by standard clinical tests and may result in treatment failure.In several com-mon gram-negative bacteria,mutations in the PhoPQ and PmrAB two-component systems are key contributors to polymyxin heteroresistance.This review aims to summarize recent research on the mechanisms of polymyxin heteroresistance in gram-negative bacteria,so as to provide insights for developing rapid detection methods and improving clinical treatment strategies.

Objective To analyze the main epidemiological characteristics of fungal infection in this hospital in the past 7 years,and to provide reference for clinical treatment and prevention and control strategies of fun-gal infection.Methods The fungal data and clinical data of related patients isolated from clinical samples in Peking Union Medical College Hospital from early January 2018 to the end of May 2024 were selected,and the main epidemiological characteristics of fungal infection in this hospital were identified and described through multi-angle statistical analysis.Results A total of 4 479 patients with filamentous fungal infection were en-rolled.The proportion of male patients[57.5％(2 576/4 479)]was higher than that of female patients[42.5％(1 903/4 143)],mainly distributed in internal medicine,Intensive Care Unit(ICU)and emergency de-partment,among which internal medicine accounted for the highest proportion[50.0％(2 241/4 479)].About 90.0％of the specimens were from the lower respiratory tract,in addition to specimens from skin and soft tis-sue,tissue,ear and blood culture.In terms of seasonal distribution,there are more patients in winter.The fun-gi were mainly composed of Aspergillus,Mucor,Cerdosporium,Fusarium and Penicillium,among which As-pergillus was the most abundant,accounting for 74.6％of the total.Aspergillus fumigatus was the most a-bundant Aspergillus,accounting for 42.5％of the total Aspergillus(1 418/3 340).Among the related infec-tions caused by mold,Aspergillus was the most common in the lower respiratory tract,accounting for 76.8％.Among them,Aspergillus fumigatus accounted for the highest proportion(33.6％).98.6％of the molds infected the ear were Aspergillus,of which Aspergillus niger and Aspergillus terreus were the most common.Skin infections are mainly caused by Sporothrix schenckii,Trichophyton rubrum,Microsporum ca-nis.The results of in vitro drug sensitivity test showed that the four common Aspergillus isolated in this hos-pital were sensitive to voriconazole,and amphotericin B had better antifungal activity against Mucorales in vitro.Conclusion Based on the main epidemiological characteristics of fungal infections in this hospital,it is recommended that special attention be paid to the admission of patients in the respiratory department during the peak infection period in autumn and winter.In the treatment of fungal infections in different regions and on different body parts,attention should be paid to the differences in the distribution of bacterial species.

The widespread application of medical artificial intelligence （AI） has brought technological breakthroughs to traditional diagnosis and treatment and has also altered the traditional doctor-patient interaction mode and formed a new doctor-patient relationship of “doctor-medical AI-patient” which faces a series of challenges. The intervention of AI may form a new “paternalistic style，” affecting the shared decision-making model. When its recommendations lack explanation， it may lead to clinical decision-making paralysis and affect the doctor-patient trust relationships. There may be confusion between the roles and responsibilities of AI and doctors in the process of medical practice， affecting the establishment of an emotionally responsible doctor-patient relationship. Through an in-depth analysis of the impact and causes of medical AI on the doctor-patient relationships， this paper proposed that a collaborative mechanism should be established between AI and professional doctors to complement each other， clarifying the auxiliary status of AI， reinforcing the dominant role of doctors， enhancing the regulatory mechanism， and dynamically improved the doctor-patient relationships to promote the healthy and orderly development of smart healthcare.

Objective: To classify the ABO blood group phenotypes of 5 cases from a family, and to explore the molecular mechanism for reduced B antigen expression in ABO blood group system. Methods: Serological identification of the ABO blood group was performed using microcolumn gel assay and saline tube method. The soluble antigens in saliva were detected by the agglutination inhibition assay. The full-length sequences and upstream promoter regions of ABO gene were sequenced for genotyping using PacBio SMRT sequencing technology. Results: The results of serological tests indicated the expression of B antigen decreased in 3 out of 5 blood samples. A mixed-field agglutination was observed with anti-B antibody. B antigen was not detected in all 5 saliva samples. The ABO genotype for all samples were ABO B.01/ABO O.01.02, and a novel mutation c. 28+5875C>T within the DNA-binding region of RUNX1 in +5.8-kb site were found in the B allele for 3 samples with reduced expression of B antigen. Conclusion: Results of serological and genetic analyses classify the 3 cases with reduced B antigen expression as B phenotype. The novel mutation c. 28+5875C>T of RUNX1 could be the key reason for reduced B antigen expression in 3 cases with B phenotype.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.