Objective: To evaluate the bone repair effect of 3D-printed magnesium (Mg)-loaded polycaprolactone (PCL) scaffolds in a rat skull defect model. Methods: PCL scaffolds mixed with Mg microparticles were prepared by using 3D printing technology, as were pure PCL scaffolds. The surface morphologies of the two scaffolds were observed by scanning electron microscopy (SEM), and the surface elemental composition was analyzed via energy dispersive spectroscopy (EDS). The physical properties of the scaffolds were characterized through contact angle measurements and an electronic universal testing machine. This study has been reviewed and approved by the Ethics Committee. A critical size defect model was established in the skull of 15 Sprague-Dawley (SD) rats, which were divided into the PCL group, PCL-Mg group, and untreated group, with 5 rats in each group. Micro-CT scanning was performed to detect and analyze skull defect healing at 4 and 8 weeks after surgery, and samples from the skull defect area and major organs of the rats were obtained for histological staining at 8 weeks after surgery. Results: The scaffolds had a pore size of (480 ± 25) μm, a fiber diameter of (300 ± 25) μm, and a porosity of approximately 66%. The PCL-Mg scaffolds contained 1.0 At% Mg, indicating successful incorporation of Mg microparticles. The contact angle of the PCL-Mg scaffolds was 68.97° ± 1.39°, indicating improved wettability compared to that of pure PCL scaffolds. Additionally, compared with that of pure PCL scaffolds, the compressive modulus of the PCL-Mg scaffolds was (57.37 ± 8.33) MPa, demonstrating enhanced strength. The PCL-Mg group exhibited the best bone formation behavior in the skull defect area compared with the control group and PCL group at 4 and 8 weeks after surgery. Moreover, quantitative parameters, such as bone volume (BV), bone volume/total volume (BV/TV), bone surface (BS), bone surface/total volume (BS/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD), of skull defects were better than those in the other groups, indicating the best bone regeneration effect. H&E, Goldner, and VG staining revealed more mineralized new bone formation in the PCL-Mg group than in the other groups, and H&E staining of the major organs revealed good biosafety of the material. Conclusion PCL-Mg scaffolds can promote the repair of bone defects and have clinical potential as a new scaffold material for the repair of maxillofacial bone defects.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. 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 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective To investigate the osteogenic properties of a methacrylated gelatin(GelMA)/bone marrow mesenchymal stem cells(BMSCs)composite hydrogel applied to the skull defect area of rats and to provide an experi-mental basis for the development of bone regeneration biomaterials.Methods This study was approved by the Animal Ethics Committee of Nanjing University.A novel photocurable composite biohydrogel was developed by constructing photoinitiators[lthium phenyl(2,4,6-trimethylbenzoyl)phosphinate,LAP],GelMA,and BMSCs.The surface morphology and elemental composition of the gel were examined using scanning electron microscopy(SEM)and energy-dispersive X-ray spectroscopy(EDX).The compressive strength of the gel was evaluated using an electronic universal testing ma-chine.After in vitro culture for 1,2,and 5 days,the proliferation of the BMSCs in the hydrogels was assessed using a CCK-8 assay,and their survival and morphology were examined through confocal microscopy.A 5 mm critical bone de-ficiency model was generated in a rat skull.The group receiving composite hydrogel treatment was referred to as the Gel-MA/BMSCs group,whereas the untreated group served as the control group.At the 4th and 8th weeks,micro-CT scans were taken to measure the bone defect area and new bone index,while at the 8th week,skull samples from the defect ar-ea were subjected to H&E staining,van Gieson staining,and Goldner staining to evaluate the quality of bone regenera-tion and new bone formation.Results SEM observed that the solidified GelMA showed a 3D spongy gel network with uniform morphology,the porosity of GelMA was 73.41％and the pore size of GelMA was(28.75±7.13)μm.EDX results showed that C and O were evenly distributed in the network macroporous structure of hydrogel.The hydrogel compres-sion strength was 152 kPa.On the 5th day of GelMA/BMSCs culture,the cellular morphology transitioned from oval to spindle shaped under microscopic observation,accompanied by a significant increase in cell proliferation(159.4％,as determined by the CCK-8 assay).At 4 weeks after surgery,a 3D reconstructed micro-CT image revealed a minimal re-duction in bone defect size within the control group and abundant new bone formation in the GelMA/BMSCs group.At 8 weeks after surgery,no significant changes were observed in the control group's bone defect area,with only limited evi-dence of new bone growth;however,substantial healing of skull defects was evident in the GelMA/BMSCs group.Quan-titative analysis at both the 4-and 8-week examinations indicated significant improvements in the new bone volume(BV),new bone volume/total bone volume(BV/TV),bone surface(BS),and bone surface/total bone volume(BS/TV)in the GelMA/BMSCs group compared to those in the control group(P＜0.05).Histological staining showed continuous and dense formation of bone tissue within the defects in the GelMA/BMSCs group and only sporadic formation of new bone,primarily consisting of fibrous connective tissue,at the defect edge in the control group.Conclusion Photocur-ing hydrogel-based stem cell therapy exhibits favorable biosafety profiles and has potential for clinical application by inducing new bone formation and promoting maturation within rat skull defects.

177Lu-prostate specific membrane antigen(PSMA)radio-ligand therapy has been approved abroad for advanced prostate cancer and has been in several clinical trials in China.Based on domestic clinical practice and experimental data and referred to international experience and viewpoints,the expert group forms a consensus on the clinical application of 177Lu-PSMA radio-ligand therapy in prostate cancer to guide clinical practice.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. 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 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective:To analyze the role of dandelion and mulberry leaf in the progression of acute myeloid leukemia(AML)by network pharmacology,and to clarify the active components and their mechanisms in treating AML.Methods:The active components of dandelion and mulberry leaf were screened by Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP).The targets were predicted by SwissTargetPrediction Database.The AML-related genes and protein targets were retrieved from the SymMap Database,the GeneCards Human Gene Database,the DisGeNET Database,and the Online Mendelian Inheritance in Man(OMIM)Database.The AML-related genes and target genes of dandelion and mulberry leaf were compared by comparative analysis and were identify by the enrichment genes,followed by Gene Ontology(GO)functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)signaling pathway enrichment analysis.The drug-active component-target network and protein-protein interaction(PPI)network were constructed by Cytoscape 3.8.0 software,and the core genes were selected by CytoNCA plugin;the molecular docking was conducted by AutoDock software.Results:After filtering by databases,39 active components were identified,and 148 common targets between dandelion-mulberry leaf and AML were collected.The GO functional enrichment analysis mainly involved cytokine-mediated signaling pathways,positive regulation of kinase activity,and oxidative stress responses.The KEGG signaling pathway enrichment analysis focused on the phosphatidylinositol 3 kinase/protein kinase B(PI3K-AKT)signaling pathway,the tumor necrosis factor(TNF)signaling pathway,and the Janus kinase/signal transducer and activator of transcription(JAK-STAT)signaling pathway.The key targets were identified by topological analysis including signal transducer and activator of transcription 3(STAT3),epidermal growth factor receptor(EGFR),protein kinase B1(AKT1),recombinant human epidermal growth factor(EGF),vascular endothelial growth factor A(VEGFA),oncogene MYC,tumor protein P53(TP53),mitogen-activated protein kinase 3(MAPK3),cysteiny asparate specific protease-3(CASP3),oncogene SRC,heat shock protein 90 alpha family class A member 1(HSP90AA1),tenascin XB1(CTNNB1),phosphoinositide kinase-3 catalytic subunit alpha(PIK3CA),interleukin 6(IL-6),TNF,mitogen-activated protein kinase 1(MAPK1),and phosphatidylinositide kinase-3 regulatory subunit 1(PIK3R1).The molecular docking results showed the highest affinity pairing to be taraxerol with MYC(-8.74 kcal·mol-1),and quercetin,kaempferol,luteolin,and artemetin demonstrated good binding affinities with various targets.Conclusion:The main active components of dandelion-mulberry leaf,such as quercetin,taraxerol,kaempferol,luteolin,and artemetin,may exert the anti-AML effect by regulating AKT1,STAT3,HSP90AA1,IL-6,and MAPK1;regulation the PI3K-AKT signaling pathway may be the critical mechanism of anti-AML effect by dandelion-mulberry leaf.

Objective To investigate the nutritional status of children with Crohn's Disease (CD) at diagnosis and its association with clinical characteristics. Methods A retrospective analysis was performed for the clinical data and nutritional status of 118 children with CD who were admitted to Beijing Children's Hospital,Capital Medical University,from January 2016 to January 2024. A multivariate logistic regression analysis was used to investigate the risk factors for malnutrition. Results A total of 118 children with CD were included,among whom there were 68 boys (57.6％) and 50 girls (42.4％),with a mean age of (11±4) years. Clinical symptoms mainly included recurrent abdominal pain (73.7％,87/118),diarrhea (37.3％,44/118),and hematochezia (32.2％,38/118),and 63.6％ (75/118) of the children had weight loss at diagnosis. The incidence rate of malnutrition was 63.6％ (75/118),and the children with moderate or severe malnutrition accounted for 67％ (50/75). There were 50 children (42.4％) with emaciation,8 (6.8％) with growth retardation,and 9 (7.6％) with overweight or obesity. Measurement of nutritional indices showed a reduction in serum albumin in 83 children (70.3％),anemia in 74 children (62.7％),and a reduction in 25 hydroxyvitamin D in 15 children (60％,15/25). The children with malnutrition had significantly higher disease activity,proportion of children with intestinal stenosis,and erythrocyte sedimentation rate and a significant reduction in serum albumin (P<0.05). The multivariate logistic regression analysis showed that intestinal stenosis was an independent risk factor for malnutrition in children with CD (OR=4.416,P<0.05). Conclusions There is a high incidence rate of malnutrition in children with CD at diagnosis,which is associated with disease activity and disease behavior. The nutritional status of children with CD should be closely monitored.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.