ObjectiveTo explore the mechanism by which Sini San （SNS） inhibits ferroptosis， alleviates inflammation and myocardial injury， and improves myocardial infarction （MI）. MethodsThe active ingredients of SNS were obtained by searching the Traditional Chinese Medicine System Pharmacology Platform （TCMSP） database， its target sites were predicted using the SwissTargetPrediction Database， and the core components were screened out using the CytoNCA plug-in. The targets of MI and ferroptosis were obtained by using GeneCards， Online Mendelian Inheritance in Man （OMIM） database， DrugBank， Therapeutic Target Database （TTD）， FerrDb database and literature review， respectively. The intersection of these targets of SNS-MI-ferroptosis was plotted as a Venn diagram. The protein-protein interaction （PPI） network was constructed using the STRING database， and the visualization graph was prepared using Cytoscape. The core targets were screened out using the CytoNCA plug-in， and the biological functions were clustered by the MCODE plug-in. Gene Ontology （GO） functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analysis were performed using the David database. Molecular docking was performed using AutoDock and visualized with PyMOL2.5.2. The Kunming mice were randomly divided into the control group， the model group， the SNS group， and the trimetazidine （TMZ） group. The mice were subcutaneously injected with isoprenaline （ISO， 5 mg·kg^-1·d^-1） to establish an MI model. The drug was continuously intervened for 7 days. The ST-segment changes were recorded by electrocardiogram （ECG）， and the tissue morphology changes were observed by hematoxylin-eosin （HE） staining. Cardiomyocyte ferroptosis was investigated by transmission electron microscopy. Serum creatine kinase （CK）， creatine kinase isoenzyme （CK-MB）， lactate dehydrogenase （LDH）， reduced glutathione （GSH）， and malondialdehyde （MDA） levels were detected by biochemical assay. Enzyme-linked immunosorbent assay （ELISA） was used to detect serum levels of interleukin （IL）-6 and 4-hydroxynonenal （4-HNE）. Immunohistochemical staining was employed to detect IL-6 and phosphorylated signal transducer and transcription activator 3 （p-STAT3） in cardiac tissues. Western blot was used to detect STAT3 and p-STAT3 in cardiac tissues. Real-time PCR was used to detect the levels of IL-6， IL-18， solute carrier family 7 member 11 （SLC7A11）， arachidonic acid 15-lipoxygenase （ALOX15）， and glutathione peroxidase 4 （GPx4） in cardiac tissues. ResultsA total of 121 active ingredients of SNS were obtained， and 58 potential targets of SNS in the treatment of MI by regulating ferroptosis were screened. The three protein modules with a score5 were mainly related to the inflammatory response. The GO function was mainly related to inflammation， and KEGG enrichment analysis showed that SNS mainly regulated ferroptosis- and inflammation- related signaling pathways. Molecular docking indicated that the core component had a higher binding force to the target site. Animal experiments confirmed that SNS reduced the level of p-STAT3 （P0.01）， down-regulated the expression of ALOX15 mRNA （P0.01）， up-regulated the level of serum GSH， and the expressions of SLC7A11 and GPx4 mRNA， reduced MDA and 4-HNE levels （P0.05， P0.01）. Additionally， SNS improved the mitochondrial injury induced by cardiomyocyte ferroptosis， reduced the area of MI， alleviated inflammation and myocardial injury， lowered the levels of serum CK， CK-MB， LDH， IL-6， and the mRNA expression levels of IL-16 and IL-18 （P0.05）， and improved ST segment elevation. ConclusionSNS can reduce ISO-induced STAT3 phosphorylation levels， inhibit ferroptosis in cardiomyocytes， alleviate inflammation and myocardial injury， thereby improving MI.

ObjectiveTo explore the mechanism by which Sini San （SNS） inhibits ferroptosis， alleviates inflammation and myocardial injury， and improves myocardial infarction （MI）. MethodsThe active ingredients of SNS were obtained by searching the Traditional Chinese Medicine System Pharmacology Platform （TCMSP） database， its target sites were predicted using the SwissTargetPrediction Database， and the core components were screened out using the CytoNCA plug-in. The targets of MI and ferroptosis were obtained by using GeneCards， Online Mendelian Inheritance in Man （OMIM） database， DrugBank， Therapeutic Target Database （TTD）， FerrDb database and literature review， respectively. The intersection of these targets of SNS-MI-ferroptosis was plotted as a Venn diagram. The protein-protein interaction （PPI） network was constructed using the STRING database， and the visualization graph was prepared using Cytoscape. The core targets were screened out using the CytoNCA plug-in， and the biological functions were clustered by the MCODE plug-in. Gene Ontology （GO） functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analysis were performed using the David database. Molecular docking was performed using AutoDock and visualized with PyMOL2.5.2. The Kunming mice were randomly divided into the control group， the model group， the SNS group， and the trimetazidine （TMZ） group. The mice were subcutaneously injected with isoprenaline （ISO， 5 mg·kg^-1·d^-1） to establish an MI model. The drug was continuously intervened for 7 days. The ST-segment changes were recorded by electrocardiogram （ECG）， and the tissue morphology changes were observed by hematoxylin-eosin （HE） staining. Cardiomyocyte ferroptosis was investigated by transmission electron microscopy. Serum creatine kinase （CK）， creatine kinase isoenzyme （CK-MB）， lactate dehydrogenase （LDH）， reduced glutathione （GSH）， and malondialdehyde （MDA） levels were detected by biochemical assay. Enzyme-linked immunosorbent assay （ELISA） was used to detect serum levels of interleukin （IL）-6 and 4-hydroxynonenal （4-HNE）. Immunohistochemical staining was employed to detect IL-6 and phosphorylated signal transducer and transcription activator 3 （p-STAT3） in cardiac tissues. Western blot was used to detect STAT3 and p-STAT3 in cardiac tissues. Real-time PCR was used to detect the levels of IL-6， IL-18， solute carrier family 7 member 11 （SLC7A11）， arachidonic acid 15-lipoxygenase （ALOX15）， and glutathione peroxidase 4 （GPx4） in cardiac tissues. ResultsA total of 121 active ingredients of SNS were obtained， and 58 potential targets of SNS in the treatment of MI by regulating ferroptosis were screened. The three protein modules with a score5 were mainly related to the inflammatory response. The GO function was mainly related to inflammation， and KEGG enrichment analysis showed that SNS mainly regulated ferroptosis- and inflammation- related signaling pathways. Molecular docking indicated that the core component had a higher binding force to the target site. Animal experiments confirmed that SNS reduced the level of p-STAT3 （P0.01）， down-regulated the expression of ALOX15 mRNA （P0.01）， up-regulated the level of serum GSH， and the expressions of SLC7A11 and GPx4 mRNA， reduced MDA and 4-HNE levels （P0.05， P0.01）. Additionally， SNS improved the mitochondrial injury induced by cardiomyocyte ferroptosis， reduced the area of MI， alleviated inflammation and myocardial injury， lowered the levels of serum CK， CK-MB， LDH， IL-6， and the mRNA expression levels of IL-16 and IL-18 （P0.05）， and improved ST segment elevation. ConclusionSNS can reduce ISO-induced STAT3 phosphorylation levels， inhibit ferroptosis in cardiomyocytes， alleviate inflammation and myocardial injury， thereby improving MI.

Objective To develop an ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） method to simultaneously determine 10 main components, including berberine, phellodendrine, specnuezhenide, mangiferin, loganin, paeoniflorin, geniposide, baicalin, and acteoside in Compound Dihuang oral solution. Methods An UPLC-MS/MS method was established with an ACQUITY UPLC BEH-C18 （2.1 mm×100 mm, 1.7 μm）column and mobile phase of 0.1% formic water（A）-methanol solution（B） in a gradient elution manner. The flow rate of mobile phase was 0.2 ml/min.The temperature of column was 30℃. The injection volume was 2 μl. The MS detection was in MRM mode. Results 10 components in Compound Dihuang oral solution had a good linear relationship within their concentration range,and the precision, repeatability, stability and recovery met the requirements. The contents of berberine, phellodendrine, specnuezhenide, mangiferin, loganin, paeoniflorin, geniposide, baicalin, and acteoside in 7 batches of samples were （89.7-95.6） μg/ml, （164.0-177.7） μg/ml, （540.0-610.0） μg/ml, （408.7-429.0） μg/ml, （726.0-825.0） μg/ml, （503.7-572.0） μg/ml, （1380.0-1540.0） μg/ml, （2596.7-2896.7) μg/ml, （4866.7-5520.0) μg/ml, （61.8-67.2) μg/ml, respectively. Conclusion The established method was easy to be repeated and operated. The contents of 10 components in Compound Dihuang oral solution could be determined quickly and accurately, which provided a reference for the quality control of hospital preparation.

Objective:To analyze the etiological characteristics, serotype distribution, drug resistance and molecular typing characteristics based on data collected by active surveillance of foodborne diseases in Shanxi Province from 2021 to 2022.Methods:Fecal and anal swabs for foodborne disease tests were collected from 17 sentinel hospitals in Shanxi Province from 2021 to 2022. The pathogens included Shigella, Salmonella, Vibrio parahaemolyticus and 5 types of diarrheagenic Escherichia coli ( E. coli). The positive strains were identified by mass spectrometry or systematic biochemistry. Salmonella and Shigella were serotyped by slide agglutination, and diarrheagenic E. coli was typed by multiplex fluorescence PCR. Vibrio parahaemolyticus was tested for tlh/ tdh/ trh virulence genes by multiplex fluorescent PCR. All strains were also tested for drug resistance by the microbroth dilution method. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE). Results:A total of 4 481 samples were collected from patients with diarrhea, and 555 target strains were detected, with a detection rate of 12.39%(555/4 481). Among them, there were 365 strains of Salmonella, 175 strains of diarrheagenic E. coli, 15 strains of Vibrio parahaemolyticus, and no Shigella. There were 32 serotypes of Salmonella, and the dominant serotypes were 158 strains of Salmonella senteritidis and 124 strains of Salmonella typhimurium. diarrheagenic E. coli classification: 79 strains of enteroaggregative E. coli, 72 strains of enteropathogenic E. coli, 23 strains of enterotoxic E. coli, 1 strain of enterohemorrhagic E. coli, and none of enteroinvasive E. coli. For Vibrio parahaemolyticus virulence gene carriage, all strains carried tlh; 11 strains (73.33%, 11/15) carried tdh only; 2 strains (13.33%, 2/15) carried trh; 1 strain (6.67%, 1/15) carried both tdh and trh genes; 1 strain (6.67%, 1/15) did not carry these two virulence genes. Antimicrobial resistance tests presented that Salmonella had the highest resistance rate to ampicillin (85.21%, 311/365), followed by naphridic acid (66.58%, 243/365), and multi-drug resistance (78.63%, 287/365), resulting in 135 drug resistance spectrums. The resistance rate of diarrheagenic E. coli to ampicillin was the highest (81.71%, 143/175), followed by tetracycline (67.43%, 118/175), and multi-drug resistance (72.57%, 127/175), resulting in 81 drug resistance spectrums. Vibrio parahaemolyticus had the highest resistance rate to cefazolin (93.33%, 14/15), followed by tetracycline (26.67%, 4/15) and multi-drug resistance (20.00%, 3/15), resulting in 3 drug resistance spectrums. A total of 158 strains of Salmonella enteritidi, 124 strains of Salmonella typhimurium, 13 strains of Salmonella london and 175 strains of DEC were typed by PFGE. Among 470 strains of PFGE typing, 6 strains of DEC were degraded by DNA, while the remaining strains obtained effective PFGE band. Salmonella enteritidi were divided into 64 PFGE band types, Salmonella typhimurium were divided into 115 PFGE band types, Salmonella london were divided into 13 PFGE band types and diarrheagenic E. coli were divided into 165 PFGE band types. Conclusions:Shigella is not detected in the active surveillance, and Salmonella is detected most frequently. Salmonella and diarrheagenic E. coli have the highest resistance rates to ampicillin, and Vibrio parahaemolyticus has the highest resistance rates to cefazolin. The PFGE classification is polymorphic, and the dominant band type is not obvious. The evidence of multi-drug resistance suggests further strengthening monitoring and management of drug resistance.

Objective Under the guidance of the Social Ecosystems Theory(SET)framework,this study explores the experience of social isolation among patients with chronic obstructive pulmonary disease(COPD),providing a basis for the development of targeted clinical interventions.Methods This study employed purposeful sampling methods.Semi-structured interviews were conducted from April to July 2024 with patients diagnosed with COPD at a tertiary hospital in Shanxi Province,China,who met the inclusion and exclusion criteria.Data were analyzed using Colaizzi's seven-step analysis method and NVivo 12.0 software.Results This study involved in-depth interviews with 15 patients suffering from COPD,totaling approximately 405 minutes of interview time and yielding over 40,000 words in transcribed text.Totally 3 main themes and 9 sub-themes were distilled,among which the microsystem level reflects the intricate interplay of individual experiences(physical functional limitations,severe negative emotions,heightened emotional imbalance,and weakened social roles);the mesosystem level pertains to the support and challenges from family and social networks(intense need for familial emotional support,widening social gaps in interactions with friends and relatives,and pronounced interpersonal communication barriers);the macrosystem level involves the integrated influence of societal and policy environments(restricted living conditions and urgent demands for policy support and service accessibility).Conclusion The social isolation experienced by patients with COPD manifests in multiple dimensions of experience.It is necessary to develop interdisciplinary and multi-level comprehensive intervention strategies for the future,to create more social opportunities and emotional connections for patients,thereby improving their quality of life.

BACKGROUND:Platelet-rich fibrin(PRF)has many advantages,such as simple preparation,low production cost,and high safety,and has been widely used in the study of bone defect repair in oral and maxillofacial surgery,but there are problems such as too fast degradation rate and short release time of growth factors. OBJECTIVE:PRF was loaded into gelatin methacryloyl(GelMA)hydrogel and its osteogenic properties were analyzed by in vivo and in vitro experiments. METHODS:(1)New Zealand white rabbit venous blood was extracted to prepare PRF.GelMA hydrogels containing 0,0.05,0.075,and 0.1 g PRF were prepared,respectively,and were recorded as GelMA,GelMA/PRF-0.05,GelMA/PRF-0.075,and GelMA/PRF-0.1,respectively,to characterize the micromorphology and in vitro slow-release properties of the hydrogels.(2)Four kinds of hydrogels were co-cultured with MC3T3-E1 cells,respectively,and the cell proliferation activity was detected with the single cultured cells as the control.After osteogenic induction,alkaline phosphatase activity,mineralization ability,mRNA and protein expression levels of osteogenic genes(osteocalcin,osteopontin,RUNX2),ERK1/2-p38 MAPK pathway protein mRNA and protein expression levels were detected.(3)Fifteen New Zealand white rabbits were taken.Four full-layer bone defects of 8 mm diameter were prepared in the skull of each rabbit,one of which was implanted without any material(blank control group),and the other three were implanted with GelMA hydrogel,PRF,and GelMA/PRF-0.1 hydrogel,respectively.The bone defect was detected by Micro-CT and bone morphology was observed at 4,8,and 12 weeks after operation. RESULTS AND CONCLUSION:(1)Scanning electron microscopy observed that all the hydrogels of the four groups had honeycomb pore structure,and the pore size of the hydrogels decreased slightly with the increase of PRF content,but there was no significant difference between the groups.The three groups of GelMA/PRF hydrogel could release transforming growth factor β1 and insulin-like growth factor 1 at a certain rate,and the cumulative release of transforming growth factor β1 and insulin-like growth factor 1 increased significantly with the extension of time.(2)CCK-8 assay and live/dead staining showed that GelMA/PRF hydrogel could promote the proliferation of MC3T3-E1 cells.The results of alkaline phosphatase staining,alizarin red staining,and osteogenic gene detection showed that GelMA/PRF hydrogel could promote the osteogenic differentiation of MC3T3-E1 cells,and inhibit the expression of ERK1/2-p38 MAPK pathway protein,and showed a PRF content dependence.(3)Micro-CT scan showed that the bone mineral density and bone volume fraction in the bone defect of GelMA/PRF-0.1 hydrogel group were higher than those in the other three groups(P<0.05).Hematoxylin-eosin staining showed that compared with the other three groups,GelMA/PRF-0.1 hydrogel group had faster and more mature new bone formation at the bone defect.(4)These findings indicate that GelMA/PRF hydrogel has good osteogenic activity both in vivo and in vitro,which may be related to inhibiting the expression of ERK1/2-p38 MAPK pathway protein.

Objective To systematically assess the spatiotemporal distribution,risk factors,and future trends of chronic obstructive pulmonary disease(COPD)among individuals under 50 years of age globally from 1990 to 2021 based on Global Burden of Disease(GBD)data in order to provide support for the formulation of prevention and control strategies of the disease.Methods The GBD data from 1990 to 2021 were analyzed for the incidence,mortality,disability-adjusted life years(DALYs),and estimated annual percentage change(EAPC)of COPD in<50-year-old individuals across 204 countries and regions.The data were stratified by age,sex,region,country,and sociodemographic index(SDI).The COPD trends until 2035 were predicted.Results In 2021,the global incidence of early-onset COPD was estimated at 2.5 million cases(95%uncertainty interval:2.09～2.96 million),representing a 50.55%increase compared to 1990.Significant regional heterogeneity was observed,with low SDI regions experiencing a 134.08%increase,whereas high SDI regions exhibited a rise-then-fall trend.Risk factor analysis identified environmental and occupational exposures(air pollution,ambient ozone pollution,household air pollution from solid fuels,etc.)and smoking as the primary etiological factors.Notably,household solid fuel exposure accounted for 50.90%of COPD-related deaths in low SDI regions,compared to only 0.03%in high SDI regions.Projections indicated that by 2035,the global burden of early-onset COPD will increase to 2.59 million cases.Conclusion The global disease burden of COPD among people under 50 years increased significantly from 1990 to 2021,with pronounced disparities across regions and socioeconomic levels.COPD deaths in low-SDI regions are strongly associated with solid fuel exposure and particulate matter pollution,and these regions are expected to remain the main drivers of global COPD incidence growth through 2035.

Objective To explore the influencing factors of cognitive impairment in non-dialysis patients with chronic kidney disease(CKD).Methods A total of 60 hospitalized non-dialysis patients with CKD in the Department of Nephrology of Northern Jiangsu People's Hospital Affiliated to Yangzhou University from September 2022 to September 2023 were enrolled as research objects.According to the estimated glomerular filtration rate(eGFR),they were divided into stage 1 to 2 of CKD group[eGFR ≥60 mL/(min·1.73 m2)]with 23 cases,the stage 3 of CKD group[eGFR 30～＜60 mL/(min·1.73 m2)]with 20 cases,and stage 4 to 5 of CKD group[eGFR＜30 mL/(min·1.73 m2)]with 17 cases.The Montreal Cognitive Assessment Scale(MoCA)was used to evaluate the cognitive function of the patients.Basic data and common clinical laboratory in-dicators on hospital admission were collected to analyze the differences in cognitive function levels under different renal function statuses and to explore the influencing factors of cognitive impairment.Results The incidence rates of cognitive impairment in the stage 1 to 2 of CKD group,stage 3 of CKD group,and stage 4 to 5 of CKD group were 47.8％,85.0％,and 94.1％respectively,the median MoCA scored 26,24 and 20 respectively,with statistically significant between-group differ-ences(P＜0.05).Cognitive function was significantly negatively correlated with age(r=-0.634,P＜0.001),blood urea nitrogen(BUN)(r=-0.574,P＜0.001),serum creatinine(Cr)(r=-0.417,P＜0.001),cystatin C(Cys-C)(r=-0.327,P=0.011),serum β2-microglobulin(β2-MG)(r=-0.259,P=0.046),and N-terminal pro-brain natriuretic peptide(NT-proBNP)(r=-0.474,P＜0.001),and was significantly positively correlated with hemoglobin(HB)(r=0.401,P=0.001)and eGFR(r=0.485,P＜0.001).Multivariate Logistic regression analysis showed that age(P=0.006)and NT-proBNP(P=0.041)were influencing factors of cognitive im-pairment in non-dialysis patients with CKD.Receiver operating characteristic(ROC)curve analysis showed that the area under the curve(AUC),sensitivity,and specificity of age for prediction were 0.860,0.864 and 0.812 respectively,the AUC,sensitivity,and specificity of NT-proBNP for pre-diction were 0.808,0.795 and 0.875 respectively,and the combined prediction of age and NT-proBNP had an AUC,sensitivity,and specificity of 0.893,0.955,and 0.750,respectively.Conclusion As renal function deteriorates,the incidence rate and severity of cognitive impairment in non-dialysis patients with CKD tend to increase.Advanced age,renal function deterioration,high NT-proBNP level,and anemia are associated with the occurrence of cognitive impairment in non-di-alysis patients with CKD,among which age and NT-proBNP are influencing factors for cognitive im-pairment.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. 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 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.