Objective To investigate the distribution and antibiotic resistance profiles of clinical isolates in Beijing Children's Hospital,Capital Medical University from 2016 to 2022.Methods All the strains isolated from inpatients in Beijing Children's Hospital during the period from 2016 to 2022 were analyzed.Antimicrobial susceptibility test was conducted by Kirby-Bauer method or automated system.Results were interpreted according to the breakpoints recommended in the CLSI Ml00 2022 edition.Results A total of 24 904 isolates were analyzed,including Gram-positive bacteria(49.4％)and Gram-negative bacteria(50.6％).The top three Gram-positive bacteria were Staphylococcus aureus(15.6％),coagulase-negative Staphylococcus(14.0％),and Streptococcus pneumoniae(8.9％).The top three Gram-negative bacteria were Klebsiella spp.(8.6％),Pseudomonas aeruginosa(8.6％),and Haemophilus influenzae(8.1％).The prevalence of methicillin-resistant strains was 30.9％in SS.aureus(MRSA)and 82.7％in coagulase-negative Staphylococcus(MRCNS).The prevalence of PRSP was 75.0％(24/32)in meningitis isolates and 2.6％(57/2 195)in non-meningitis isolates.Five strains of E.faecium and 10 strains of E.faecalis were found resistant to linezolid.Two strains of E.faecium were resistant to vancomycin.The prevalence of extended-spectrum beta-lactamases(ESBLs)and carbapenem-resistant strains(CREco)in E.coli isolates was 69.0％and 9.7％,respectively.The prevalence of ESBLs and carbapenem-resistant strains(CRKpn)in K.pneumoniae isolates was 73.7％,and 37.2％,respectively.The prevalence of carbapenem-resistant strains was 21.9％in P.aeruginosa isolates and 59.3％in A.baumannii isolates.β-lactamase was detected in 68.3％of the H.influenzae isolates.Conclusions Antimicrobial resistance is still serious in children.It is necessary to strength the surveillance of bacterial resistance and use antibiotics rationally in order to curb the spread of drug-resistant strains.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Iron overload refers to the pathological state in which the iron content in the body exceeds physiological requirements,Resultsing in the deposition of iron in the organs.Iron overload mouse models are an important tool for the study of iron metabolism disorders and related diseases.This paper summarizes the commonly used modeling method used in the construction of iron overload mouse models,which mainly comprise two categories.(1)exogenous iron overload mouse models,constructed through supplementation with extraenteral iron(injected iron)or intraintestinal iron(oral iron);(2)spontaneous iron overload models,constructed by screening for specific mouse lines or modifying iron metabolism-related genes.The method involving extraenteral iron supplementation has a short modeling duration and a high success rate,making it suitable for single and composite iron overload models.However,the high iron absorption rate may cause toxic reactions;thus,the optimal dose needs to be determined in advance.By contrast,intraintestinal iron supplementation is simple and safe,but has a low iron absorption rate and a long modeling duration.The spontaneous iron overload model is mainly used for specific genetic research studies,which are complex and involve high costs.The various modeling method offer diverse research pathways,spanning from molecular to systemic levels.This diversity is conducive to gaining an in-depth understanding of the pathological mechanisms underlying iron overload and provides an experimental basis for the development of new treatments.

Objective To investigate the distribution and antibiotic resistance profiles of clinical isolates in Beijing Children's Hospital,Capital Medical University from 2016 to 2022.Methods All the strains isolated from inpatients in Beijing Children's Hospital during the period from 2016 to 2022 were analyzed.Antimicrobial susceptibility test was conducted by Kirby-Bauer method or automated system.Results were interpreted according to the breakpoints recommended in the CLSI Ml00 2022 edition.Results A total of 24 904 isolates were analyzed,including Gram-positive bacteria(49.4％)and Gram-negative bacteria(50.6％).The top three Gram-positive bacteria were Staphylococcus aureus(15.6％),coagulase-negative Staphylococcus(14.0％),and Streptococcus pneumoniae(8.9％).The top three Gram-negative bacteria were Klebsiella spp.(8.6％),Pseudomonas aeruginosa(8.6％),and Haemophilus influenzae(8.1％).The prevalence of methicillin-resistant strains was 30.9％in SS.aureus(MRSA)and 82.7％in coagulase-negative Staphylococcus(MRCNS).The prevalence of PRSP was 75.0％(24/32)in meningitis isolates and 2.6％(57/2 195)in non-meningitis isolates.Five strains of E.faecium and 10 strains of E.faecalis were found resistant to linezolid.Two strains of E.faecium were resistant to vancomycin.The prevalence of extended-spectrum beta-lactamases(ESBLs)and carbapenem-resistant strains(CREco)in E.coli isolates was 69.0％and 9.7％,respectively.The prevalence of ESBLs and carbapenem-resistant strains(CRKpn)in K.pneumoniae isolates was 73.7％,and 37.2％,respectively.The prevalence of carbapenem-resistant strains was 21.9％in P.aeruginosa isolates and 59.3％in A.baumannii isolates.β-lactamase was detected in 68.3％of the H.influenzae isolates.Conclusions Antimicrobial resistance is still serious in children.It is necessary to strength the surveillance of bacterial resistance and use antibiotics rationally in order to curb the spread of drug-resistant strains.

Iron overload refers to the pathological state in which the iron content in the body exceeds physiological requirements,Resultsing in the deposition of iron in the organs.Iron overload mouse models are an important tool for the study of iron metabolism disorders and related diseases.This paper summarizes the commonly used modeling method used in the construction of iron overload mouse models,which mainly comprise two categories.(1)exogenous iron overload mouse models,constructed through supplementation with extraenteral iron(injected iron)or intraintestinal iron(oral iron);(2)spontaneous iron overload models,constructed by screening for specific mouse lines or modifying iron metabolism-related genes.The method involving extraenteral iron supplementation has a short modeling duration and a high success rate,making it suitable for single and composite iron overload models.However,the high iron absorption rate may cause toxic reactions;thus,the optimal dose needs to be determined in advance.By contrast,intraintestinal iron supplementation is simple and safe,but has a low iron absorption rate and a long modeling duration.The spontaneous iron overload model is mainly used for specific genetic research studies,which are complex and involve high costs.The various modeling method offer diverse research pathways,spanning from molecular to systemic levels.This diversity is conducive to gaining an in-depth understanding of the pathological mechanisms underlying iron overload and provides an experimental basis for the development of new treatments.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective To study the potential harmful effects of brake-pad sourced particles.Methods Grind the brake pad particles or antimony sulfide particles.Mice were exposed brake pad or antimony sulfide particles by tracheal perfusion for 1 month.We observed pathological changes to the lungs,heart,and liver,and analyzed changes in peripheral blood macrophages and regulatory T cells(Tregs)via flow cytometry.Results After exposure,the deposition of foreign substances in the alveolar wall of mice was seen,with the obvious infiltration of inflammatory cells around blood vessels,which worsened with increasing particle concentration.Pathological changes,such as vascular inflammation and microthrombosis in the heart and hepatocyte swelling in the liver,were observed.Treg cells in peripheral blood decreased and macrophages increased in the antimony sulfide group and low-dose brake pad particles group,while the proportion of M2-type macrophages decreased,in the antimony sulfide group and low-dose brake pad particle group.Conclusions Exposure to brake pad particles and their component antimony sulfide has varying degrees of toxic effects on the lung,heart,and liver of mice and has an impact on the immune system,indicating the potential health hazards of brake-pad-derived air pollution.

Objective:To study the genetic characteristics and genetic evolution of echovirus 30 (ECHO30) isolates in Yunnan Province, China.Methods:Virus isolation was performed on nucleic acid-positive samples for hand, foot, and mouth disease pathogen surveillance in Yunnan Province, and VP1 gene sequencing was performed. The sequences of eight ECHO30 isolates from Yunnan Province and the gene sequences of the VP1 region of the ECHO30 reference strain downloaded from GenBank were compared and analyzed using MEGA 5.0 software, and then a phylogenetic tree was constructed to measure the homology of nucleotides and amino acids between the isolates.Results:The ECHO30 virus was distributed in Wenshan, Qujing, Chuxiong, and Kunming in Yunnan Province. The ECHO30 virus was relatively common in Wenshan. ECHO30 isolates belonged to the H2 subtype of the H genotype, which was close to the local reference strain LC120939 in Yunnan Province. On the VP1 gene at site 5, the amino acid change ratio was more active, the amino acids were diverse, and mutations also occurred at sites 54, 156, 258, and so on. Nucleotide and amino acid homology were 84.0% - 100.0% and 98.4% - 100.0%, respectively.Conclusions:ECHO30 isolates from Yunnan Province have certain geographical characteristics and belong to H2 of the H genotype. The nucleotide differences in virus sequences among subtypes are small and have a close genetic relationship.

Objective:To observe the efficacy of intravitreal injection of conbercept (IVC) combined with subthreshold micropulse laser photocoagulation (SMLP) in the treatment of diabetic macular edema (DME).Methods:A randomized controlled trial. From December 2020 to January 2022, 100 patients (100 eyes) with DME diagnosed by examination in Shanxi Aier Eye Hospital were included in the study. The patients were randomly divided into IVC group (50 eyes) and IVC+SMLP group (50 eyes). All the eyes were treated with IVC once a month for 3 times, and the eyes in IVC+SMLP group were treated with SMLP within 2 weeks after IVC. All affected eyes were examined by best corrected visual acuity (BCVA), which was statistically converted to logarithm of the minimum angle of resolution (logMAR) visual acuity. The central macular thickness (CMT) was measured by optical coherence tomography. Before the treatment, the logMAR BCVA of patients in IVC group and IVC+SMLP group were 0.56±0.04 and 0.55±0.03, respectively. The CMT were (437.36±11.35) μm and (434.58±10.88) μm, respectively. There was no significant difference in logMAR BCVA and CMT between the two groups ( t= 0.476, 1.027; P>0.05). The patients were followed up for 12 months after treatment. The times of IVC and the changes of BCVA and CMT were compared between the two groups. Independent sample t-test was used to compare the logMAR BCVA, CMT and times of IVC between groups. Results:After 12 months treatment, the logMAR BCVA of IVC group and IVC+SMLP group were (241.63±29.79) μm and (240.47±30.46) μm, respectively. Compared with those before treatment, 12 months after treatment, the BCVA of the two groups increased significantly ( t=7.014, 5.608; P<0.001), while CMT decreased significantly ( t=8.126, 6.013; P<0.001). There was no significant difference in BCVA and CMT between the two groups ( t=0.835, 0.764; P>0.05). The number of IVC in IVC group and IVC+SMLP group were (8.15±2.04) times and (5.91±1.80) times, respectively, and the difference was statistically significant ( t=5.210, P<0.001). Conclusions:Both IVC+SMLP and IVC alone can effectively reduce CMT and increase BCVA in patients with DME. Combination therapy can reduce the number of IVC.

Objective:To analyze the risk factors of bronchopulmonary dysplasia(BPD)in very preterm infants(VPI), and to provide scientific basis for the prevention and treatment of BPD in VPI.Methods:A prospective multicenter study was designed to collect the clinical data of VPI in department of neonatology of 28 hospitals in 7 regions from September 2019 to December 2020.According to the continuous oxygen dependence at 28 days after birth, VPI were divided into non BPD group and BPD group, and the risk factors of BPD in VPI were analyzed.Results:A total of 2 514 cases of VPI including 1 364 cases without BPD and 1 150 cases with BPD were enrolled.The incidence of BPD was 45.7%.The smaller the gestational age and weight, the higher the incidence of BPD( P<0.001). Compared with non BPD group, the average birth age, weight and cesarean section rate in BPD group were lower, and the incidence of male infants, small for gestational age and 5-minute apgar score≤7 were higher( P<0.01). In BPD group, the incidences of neonatal respiratory distress syndrome(NRDS), hemodynamically significant patent ductus arteriosus, retinopathy of prematurity, feeding intolerance, extrauterine growth restriction, grade Ⅲ~Ⅳ intracranial hemorrhage, anemia, early-onset and late-onset sepsis, nosocomial infection, parenteral nutrition-associated cholestasis were higher( P<0.05), the use of pulmonary surfactant(PS), postnatal hormone exposure, anemia and blood transfusion were also higher, and the time of invasive and non-invasive mechanical ventilation, oxygen use and total hospital stay were longer( P<0.001). The time of starting enteral nutrition, cumulative fasting days, days of reaching total enteral nutrition, days of continuous parenteral nutrition, days of reaching 110 kcal/(kg·d) total calorie, days of reaching 110 kcal/(kg·d) oral calorie were longer and the breastfeeding rate was lower in BPD group than those in non BPD group( P<0.001). The cumulative doses of amino acid and fat emulsion during the first week of hospitalization were higher in BPD group( P<0.001). Multivariate Logistic regression analysis showed that NRDS, invasive mechanical ventilation, age of reaching total enteral nutrition, anemia and blood transfusion were the independent risk factors for BPD in VPI, and older gestational age was the protective factor for BPD. Conclusion:Strengthening perinatal management, avoiding premature delivery and severe NRDS, shortening the time of invasive mechanical ventilation, paying attention to enteral nutrition management, reaching whole intestinal feeding as soon as possible, and strictly mastering the indications of blood transfusion are very important to reduce the incidence of BPD in VPI.