ObjectiveBased on transcriptomics， to explore the mechanism of Hei Xiaoyaosan regulating the phosphatidylinositol 3-kinase/protein kinase B （PI3K/Akt） signaling pathway to improve the learning and memory ability of insomnia rats with liver depression syndrome. MethodsSixty 8-week-old male SD rats were randomly divided into the blank group， model group， eszopiclone group （0.09 mg·kg^-1）， and low， medium， and high dose groups of Hei Xiaoyaosan （3.82， 7.65， 15.30 g·kg^-1）， with ten rats in each group. Except for the blank group， the other groups were induced insomnia rat model with liver depression by chronic restraint， tail clamping stimulation and intraperitoneal injection of p-chlorophenylalanine （PCPA）. Each treatment group received intragastric administration according to the specified dosage， once a day for 14 consecutive days. The pentobarbital sodium cooperative sleep test， open field test， and Morris water maze test were used to test the sleep quality， depressive-like behavior， and learning and memory abilities of rats. Additionally， enzyme-linked immunosorbent assay （ELISA） was used to detect the contents of 5-hydroxytryptamine （5-HT）， γ-aminobutyric acid （GABA）， brain-derived neurotrophic factor （BDNF）， glial cell line-derived neurotrophic factor （GDNF） and nitric oxide （NO） in hippocampus. Hematoxylin-eosin （HE） staining was performed to observe pathological changes of the hippocampal tissue， while terminal deoxynucleotidyl transferase deoxyuridine triphosphate （dUTP） nick end labeling （TUNEL） was used to evaluate apoptosis of hippocampal neurons. Transcriptomic sequencing technology was employed to identify differentially expressed genes in hippocampus between the model group and the blank group， as well as between the medium-dose group of Hei Xiaoyaosan and the model group. Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） enrichment analysis were performed on the intersecting genes. Subsequently， the enriched key genes and signaling pathways were analyzed and verified. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was utilized to assess the mRNA expression levels of phosphatase and tensin homolog （PTEN）， B-cell lymphoma-2 （Bcl-2）-like protein 11 （BCL2L11）， and mitogen-activated protein kinase 1 （MAPK1） in hippocampus， and Western blot was employed to evaluate the protein expressions of PI3K， phosphorylation （p）-PI3K， Akt， p-Akt， Bcl-2， Bcl-2-associated X protein （Bax）， and cleaved Caspase-3 in the same tissue. ResultsCompared with the blank group， the model group exhibited a reduction in body weight， an increase in sleep latency， and a decrease in sleep duration （P<0.01）. Additionally， rats showed obvious depression-like behavior， and their learning and memory abilities decreased. Furthermore， the contents of 5-HT， GABA， NO， BDNF and GDNF in hippocampus decreased （P<0.01）. Histological examination revealed a disorganized cell arrangement in the CA1 region of the hippocampus， characterized by irregular cell shapes， a reduced cell count， deeply stained and pyknotic nuclei， increased vacuolar degeneration， and an elevated apoptosis rate （P<0.01）. Compared with the model group， the body weight of the high and medium dose groups of Hei Xiaoyaosan increased， the sleep latency shortened and the sleep time prolonged （P<0.05， P<0.01）. Additionally， depression-like behavior and learning and memory abilities of rats were significantly improved， the levels of 5-HT， GABA， NO， BDNF and GDNF in the hippocampus increased （P<0.05， P<0.01）. These interventions also ameliorated pathological damage in the hippocampal CA1 area and reduced the apoptosis of hippocampal neurons （P<0.01）. Transcriptomic sequencing results indicated that Hei Xiaoyaosan might exert a therapeutic effect by regulating PI3K/Akt pathway through key mRNAs such as PTEN， BCL2L11， and MAPK1. The roles of these key mRNAs and proteins within PI3K/Akt pathway were further validated. In comparison to the blank group， the expression levels of PTEN， BCL2L11 and MAPK1 mRNA in the hippocampus of rats in the model group were increased （P<0.01）， while the protein expression levels of p-PI3K， p-Akt and Bcl-2 were decreased （P<0.01）， and the protein expression levels of PTEN， Bax and cleaved Caspase-3 were increased （P<0.01）. Compared with the model group， the high-dose and medium-dose groups of Hei Xiaoyaosan could down-regulate the expressions of PTEN， BCL2L11 and MAPK1 mRNAs （P<0.01）， up-regulate the expressions of p-PI3K， p-Akt and Bcl-2 proteins （P<0.01）， and down-regulate the protein expressions of PTEN， Bax and cleaved Caspase-3 （P<0.05， P<0.01）. ConclusionHei Xiaoyaosan may regulate PI3K/Akt signaling pathway by down-regulating expressions of key genes such as PTEN， BCL2L11 and MAPK1， and thus improve the learning and memory abilities of insomnia rats with liver depression syndrome.

Objective: Exploring the effect and mechanism of Xinyang Tablet on reduction of ferroptosis in myocardial cells from mice with chronic heart failure. Methods: Sixty C57BL/6J mice were randomly assigned to the sham, model, Xinyang Tablet low-dose (0.34 g/kg), Xinyang Tablet medium-dose (0.68 g/kg), Xinyang Tablet high-dose (1.36 g/kg), and perindopril (0.607 mg/kg) groups using a random number table method (10 mice in each group). Except for the sham group, all other groups underwent aortic arch constriction surgery to construct a chronic heart failure model. On the third day after completion of the modeling, each treatment group was administered the corresponding medication by gavage, while the sham and model groups were administered equal volumes of water by gavage once a day for eight consecutive weeks. After treatment, cardiac ultrasound was used to detect the structure and function of the mouse heart. Hematoxylin and eosin staining was used to detect pathological changes in mouse heart tissue. Masson staining was used to detect the proportion of fibrotic area of mouse heart tissue. Realtime fluorescence PCR was used to detect the mRNA expression of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), collagen 3α (Col3α), and myosin heavy chain 7 (MYH7) in mouse myocardial tissue. Transmission electron microscope was used to detect the ultrastructure of myocardial cell mitochondria. Reactive oxygen species (ROS) staining was used to detect the mean fluorescence intensity of ROS in myocardial tissue. Micro-determination was used to detect superoxide dismutase (SOD) activity in myocardial tissue. An immunofluorescence assay was used to detect the mean fluorescence intensity of phosphorylated histone deacetylase 2 (p-HDAC2) in myocardial cell. Western blotting was used to detect the protein expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), p-HDAC2, nicotinamide adenine dinucleotide phosphate oxidase 1 (NOX1), glutathione peroxidase 4 (GPX4), and cystine glutamate reverse transporter (xCT) in mouse myocardial tissue. Results: Compared to the sham group, the model group showed a decrease in left ventricular ejection fraction (LVEF), left ventricular fraction shortening (LVFS), an increase in left ventricular end-systolic diameter(LVESD) and left ventricular end-diastolic diameter (LVEDD), an increase in the proportion of cardiac fibrosis area, an increase in relative expression levels of ANP, BNP, Col3α, and MYH7 mRNA, an increase in ROS mean fluorescence intensity, a decrease in SOD activity, an increase in mean fluorescence intensity of p-HDAC2, an increase in relative expression levels of p-HDAC2 and NOX1 proteins, and a decrease in relative expression levels of Nrf2, GPX4, and xCT proteins (P<0.05). Myocardial fibrosis lesions are obvious, with disordered mitochondrial arrangement, decreased volume and shrinkage, increased membrane density, and reduced mitochondrial cristae. Compared to the model group, the LVEF and LVFS of mice in each dose group of Xinyang Tablet and the perindopril group increased, LVESD and LVEDD decreased, the proportion of fibrotic area of heart tissue decreased, the relative expression levels of ANP, BNP, Col3α, MYH7 mRNA decreased, ROS mean fluorescence intensity decreased, SOD activity increased, mean fluorescence intensity of p-HDAC2 decreased, relative expression levels of p-HDAC2 and NOX1 proteins decreased, and relative expression levels of Nrf2 and xCT proteins increased (P<0.05). Myocardial fibrosis was reduced, the mitochondrial arrangement was more regular, the mitochondria enlarged, the membrane density was reduced, and mitochondrial cristae increased. Compared to the model group, the relative expression level of the GPX4 protein in myocardial tissue increased in the Xinyang Tablet medium-, high-dose, and the perindopril groups (P<0.05). Conclusion Xinyang Tablet can improve ferroptosis and ventricular remodeling in mice with chronic heart failure by regulating the HDAC2-mediated Nrf2 antioxidant pathway.

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.

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.

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 investigate the bacterial isolate distribution and differences of antimicrobial resistance among community-acquired infection，healthcare-associated infection and hospital-acquired infection.Methods:Bacterial isolates from clinical specimens were collected in Xi'an No.1 Hospital between January 2019 and December 2023 and categorized into community-acquired infection（CAI），healthcare-associated infection（HCAI）and hospital-acquired infection（HAI）. The bacterial distribution and antimicrobial resistance differences among the three groups were compared. Data were analyzed with SPSS 22.0 statistical software.Results:A total of 9 762 bacterial strains were collected：2 258 strains（23.1%）in CAI group，763 strains（7.8%）in HCAI group and 6 741 strains（69.1%）in HAI group. In HCAI group，the detection rate of Escherichia coli was lower than that in CAI group，and higher than that in HAI group（ χ2=106.335 and 69.603，both P<0.001）. The detection rates of Pseudomonas aeruginosa and Acinetobacter baumannii in HCAI group were higher than those in CAI group（ χ2=35.749 and 65.098，both P<0.001），and lower than those in HAI group（ χ2=26.350 and 115.885，both P<0.001）. The detection rate of Staphylococcus aureus in HCAI group was higher than that in CAI and HAI groups（ χ2=5.745 and 13.992，both P<0.05）. In HCAI group，the detection rate of methicillin-resistant Staphylococcus aureus（MRSA）was lower than that in HAI group（ χ2=69.005， P<0.001）；and MRSA in HCAI demonstrated higher resistance to levofloxacin and moxifloxacin than that in CAI group（ χ2=13.634 and 13.083，both P<0.001），and lower than that in HAI group（ χ2=17.927 and 21.937，both P<0.001）. The resistance rates of Escherichia coli to piperacillin/tazobactam，ceftriaxone，ceftazidime，cefoperazone/sulbactam，ciprofloxacin and levofloxacin in HCAI group were higher than those in CAI group，and the resistance rates to cefoperazone/sulbactam，meropenem，imipenem and amikacin in HCAI group were lower than those in HAI group（all P<0.05）. For Klebsiella pneumoniae，the resistance rate in HCAI group was higher than that in CAI group and lower than that in HAI group to all antibacterial agents，except for nitrofurantoin（all P<0.01）. For Pseudomonas aeruginosa，the resistance rate in HCAI group was higher than that in CAI group（ χ2=14.107，14.819，16.822 and 15.998，all P<0.001）and lower than that in HAI group（ χ2=7.821，4.671，18.070 and 17.552，all P<0.05）to piperacillin/tazobactam，cefoperazone/sulbactam，meropenem and imipenem. Acinetobacter baumannii in HCAI group demonstrated lower resistance to piperacillin/tazobactam，meropenem，imipenem，ciprofloxacin and levofloxacin than that in HAI group（ χ2=32.263，31.526，42.417，25.277 and 6.798，all P<0.01）. Conclusion:The bacterial distribution and antimicrobial resistance in HCAI group are different from CAI and HAI groups. It is recommended to carry out precise antibiotic resistance surveillance in different categories of infections for rational antibiotic use.

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.

ObjectiveBased on ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS）， network pharmacology and pharmacodynamics， to investigate the pharmacodynamic material basis and mechanism of Hei Xiaoyaosan in improving learning and memory ability of insomnia rats. MethodUPLC-Q-TOF-MS was used to characterize the chemical constituents of Hei Xiaoyaosan. Network pharmacology was applied to construct the network of active ingredients-intersecting targets-pathways， and molecular docking was performed on key ingredients and core targets. Sixty 8-week-old male SD rats were selected and randomly divided into blank group， model group， Hei Xiaoyaosan low， medium， and high dose groups（3.82， 7.65， 15.30 g·kg^-1）， and zolpidem tartrate group（0.5 mg·kg^-1）， with 10 rats in each group. Except for the blank group， the insomnia model was induced by intraperitoneal injection of p-chlorophenylalanine（PCPA） for 4 consecutive days. Rats in each dosing group were administered the corresponding dose by gavage， once a day for 14 consecutive days. Morris water maze test was utilized to assess the learning and memory ability of rats， transmission electron microscopy was employed to examine the ultrastructure of hippocampal synapses， enzyme-linked immunosorbent assay（ELISA） was conducted to analyze the levels of 5-hydroxytryptamine（5-HT）， interleukin-6（IL-6）， and tumor necrosis factor-α（TNF-α） in hippocampal tissues， and Western blot was performed to detect the expression levels of tumor suppressor protein p53（TP53）， rat sarcoma virus（RAS）， epidermal growth factor receptor（EGFR）， cyclic adenosine monophosphate（cAMP）-response element binding protein（CREB） binding protein（CREBBP）， glycogen synthase kinase-3β（GSK-3β）， protein kinase B1（Akt1）， nitric oxide synthase 1（NOS1）， phosphorylated（p）-Akt1， and p-GSK-3β in hippocampal tissues. Additionally， real-time fluorescence quantitative polymerase chain reaction（Real-time PCR） was used to assess the mRNA expression levels of TP53， RAS， EGFR， CREBBP， GSK-3β， Akt1 and NOS1. ResultA total of 176 components were identified in Hei Xiaoyaosan， mainly flavonoids， triterpene saponins， phenylpropanoids and other compounds. Network pharmacological analysis revealed that TP53， V-Ha-Ras Harvey Rat sarcoma viral oncogene homolog（HRAS）， neuroblastoma sarcoma viral oncogene homolog（NRAS）， EGFR， CREBBP， GSK-3β， Akt1 and NOS1 were the key targets of Hei Xiaoyaosan in treating insomnia. The core targets were predominantly associated with cAMP， RAS， Ras-associated protein 1（Rap1）， advanced glycation end products（AGE）/receptor for AGE（RAGE）， and EGFR signaling pathways， and the key active ingredients of Hei Xiaoyaosan in treating insomnia were 8-shogaol， ligustilide F， 6-gingerol， levistilide A and senkyunolide E. Animal experiment results demonstrated that Hei Xiaoyaosan medium and high dose groups significantly increased body weight， shortened sleep latency and prolonged sleep duration in insomnia rats（P<0.01）， significantly decreased escape latency and increased platform crossing frequency（P<0.01）， and improved the pathological changes of hippocampal synaptic ultrastructure. Meanwhile， the two groups could significantly elevate 5-HT level， Akt1 mRNA expression， Akt1 and p-Akt1 protein expression（P<0.01）， reduce inflammatory factor levels（P<0.01）， and down-regulate protein expression levels of TP53， RAS， NOS1， EGFR， CREBBP， GSK-3β and p-GSK-3β（P<0.01）， as well as mRNA expression levels of TP53， RAS， NOS1， EGFR， CREBBP and GSK-3β in hippocampal tissues（P<0.01）. ConclusionThis study determined that the five key active ingredients（8-shogaol， ligustilide F， 6-gingerol， levistilide A and senkyunolide E） in Hei Xiaoyaosan may improve the learning and memory ability of insomnia rats by regulating signaling pathways such as cAMP， RAS， and EGFR， providing an important reference for its mechanism research and clinical application.