Objective To establish models for real-time dynamic monitoring of intracellular cytoplasmic adenosine triphosphate(ATP)and mitochondrial ATP levels in cells in order to study the changes in metabolic processes.Methods The lentiviral plasmids of the cytoplasmic chemogenetic green fluorescent protein(GFP)ATP probe(Chemo-G)and those of the mitochondrial-localized chemogenetic GFP ATP probe(mito-Chemo-G)were constructed before being transfected into HEK293T together with the helper plasmids,respectively.Chemo-G and mito-Chemo-G lentiviruses were obtained.HeLa cells were infected with the lentivirus.Puromycin resistance selection and flow cytometry cell sorting were employed to identify and isolate the infected HeLa cells.The growth and GFP expressions of HeLa cells were observed.A live-cell imaging system was used for continuous imaging of the cells,with stimuli added at specific time points to alter intracellular ATP levels to observe changes in the fluorescence intensity of the ATP probe.Results Lentiviral plasmids containing Chemo-G and mito-Chemo-G sequences were constructed.Two cell lines which could stably express Chemo-G and mito-Chemo-G were established that exhibited strong growth and accurate intracellular fluorescence localization.Live-cell imaging revealed that after the addition of 2-deoxy-D-glucose(2-DG)into HeLa-Chemo-G,the fluorescence resonance energy transfer(FRET)/GFP ratio showed a decrease that was partially reversed by the addition of glucose.The FRET/GFP ratio increased after histamine stimulation,but rapidly decreased after the addition of oligomycin.Conclusion The Chemo-G and mito-Chemo-G lentiviral vectors and stably transfected cell lines HeLa-Chemo-G and HeLa-mito-Chemo-G are constructed,which provides reliable experimental models for studying cellular metabolism and changes in intracellular ATP levels.

Objective To establish a stable in vitro model of CD8+T cell exhaustion.Methods CD8+T cells were isolated and purified from the spleens of ovalbumin-specific CD8+T cell receptor(OT-I)transgenic mice and subjected to chronic antigen stimulation to induce exhaustion in vitro.Flow cytometry was employed to evaluate the expressions of exhaustion markers,secretion of effector cytokines,and transcription factor profiles in CD8+T cells.Exhausted and effector(non-exhausted)CD8+T cells were co-cultured with tumor cells before tumor cell viability was measured to assess the cytotoxic potential of CD8+T cells.Additionally,N-acetyl-L-cysteine(N-AC)was used as a positive control during exhaustion induction to validate the model.Results Chronic stimulation resulted in a significant upregulation of inhibitory receptors,including programmed cell death protein 1(PD-1),T cell immunoglobulin and mucin domain-containing protein 3(TIM-3),T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motifdomain(TIGIT),and lymphocyte activation gene 3(LAG-3).Concurrently,the secretion of key effector cytokines such as tumor necrosis factor-α(TNF-α)and interferon-γ(IFN-γ)was markedly reduced.Exhausted CD8+T cells exhibited diminished cytotoxicity against tumor cells compared to effector CD8+T cells.Notably,treatment with N-AC effectively restored the function of exhausted CD8+T cells and enhanced their anti-tumor activity.Conclusion This study has established an effective in vitro model for CD8+T cell exhaustion.The use of N-AC demonstrates its potential to restore functionality in exhausted CD8+T cells,underscoring the reliability and utility of this model for investigating the anti-tumor potential of exhausted T cells.

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 T o verify and compare the values of the different risk assessment scores in prediction of in-fections in the ST elevation myocardial infarction(STEMI)patients undergoing percutaneous coronary interven-tion(PCI)therapy.METHODS A total of 226 STEMI patients who received PCI in The Second Medical Center of Chinese PLA General Hospital from Aug.2019 to Jul.2024 were recruited as the research subjects.The efficien-cies of the six types of risk assessment scores,including age,serum creatinine,or glomerular filtration rate/ejec-tion fraction(ACEF/AGEF)score,Canadian acute coronary syndrome(C ACS)score,embolism risk score 2(CHADS2)score,global register of acute coronary events(GRACE)score and for contrast induced nephropathy(Mehran)scorein prediction of infections and major adverse clinical events(M ACE)were analyzed.RESULTS All of the risk assessment scores showed remarkable discriminating capability in prediction of infections(AUC:0 746 to 0 791)except CHADS2 score[the area under the curve(AUC)=0.682;95％CI=0.652 to 0.712)].All of the risk assessment scores showed the excellent performance in calibration of infections except CACS risk assess-ment score(calibration slope=0.77;95％CI=0.18 to 1.35).The risk assessment scores also showed tremen-dous capability in discriminating MACE during the hospital stay except CHADS2 score,with the AUC ranging be-tween 0.700 and 0.786.All of the six types of risk assessment scores showed the most excellent performance in calibration of MACE during the hospital stay.CONCLUSION ACEF,AGEF,CACS,GRACE and Mehran scores show remarkable discriminating capability and calibration in prediction of infections and MACE.

OBJECTIVE T o verify and compare the values of the different risk assessment scores in prediction of in-fections in the ST elevation myocardial infarction(STEMI)patients undergoing percutaneous coronary interven-tion(PCI)therapy.METHODS A total of 226 STEMI patients who received PCI in The Second Medical Center of Chinese PLA General Hospital from Aug.2019 to Jul.2024 were recruited as the research subjects.The efficien-cies of the six types of risk assessment scores,including age,serum creatinine,or glomerular filtration rate/ejec-tion fraction(ACEF/AGEF)score,Canadian acute coronary syndrome(C ACS)score,embolism risk score 2(CHADS2)score,global register of acute coronary events(GRACE)score and for contrast induced nephropathy(Mehran)scorein prediction of infections and major adverse clinical events(M ACE)were analyzed.RESULTS All of the risk assessment scores showed remarkable discriminating capability in prediction of infections(AUC:0 746 to 0 791)except CHADS2 score[the area under the curve(AUC)=0.682;95％CI=0.652 to 0.712)].All of the risk assessment scores showed the excellent performance in calibration of infections except CACS risk assess-ment score(calibration slope=0.77;95％CI=0.18 to 1.35).The risk assessment scores also showed tremen-dous capability in discriminating MACE during the hospital stay except CHADS2 score,with the AUC ranging be-tween 0.700 and 0.786.All of the six types of risk assessment scores showed the most excellent performance in calibration of MACE during the hospital stay.CONCLUSION ACEF,AGEF,CACS,GRACE and Mehran scores show remarkable discriminating capability and calibration in prediction of infections and MACE.

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 construct an NZB/W(F1)mouse model of systemic lupus erythematosus and evaluate the effects of nicotinamide on each index of lupus nephritis pathogenesis of NZB/W(F1)mice in order to provide data for research on the role of nicotinamide in the treatment of lupus nephritis.Methods Female NZB/W(F1)mice were obtained by crossing male NZW mice with female NZB ones.Urine samples were collected using metabolic cages and proteinuria test strips were used to detect proteinuria.Blood samples were collected through the orbital venous plexus in mice.Enzyme-linked immunosorbent assay(ELISA)was used to detect the level of anti-dsDNA antibody.Levels of serum creatinine and urea nitrogen and liver function indexes were detected using an automatic blood analyzer.Hematoxylin-eosin staining and immunofluorescence technique were used to detect the pathological state of the kidney.Results The levels of proteinuria,double-stranded DNA antibodies,serum creatinine,and urea nitrogen were gradually increased during the natural course of the disease in female NZB/W(F1)mice,indicating that the lupus nephritis disease model was constructed in female NZB/W(F1)mice.Compared to the control group,nicotinamide feeding could obviously decrease the level of proteinuria(P=0.0070),inhibit the production of double-stranded DNA antibodies(P=0.0325),and retard the progression of serum creatinine(P=0.0067)and urea nitrogen indexes(P=0.0166)in serum.In addition,the pathological state of the kidney in the nicotinamide feeding group was significantly alleviated compared with the control group.Conclusion A lupus nephritis disease model is constructed in NZB/W(F1)mice.Nicotinamide feeding can obviously alleviate the disease state of lupus nephritis in NZB/W(F1)mice.

Objective:To understand the current situation of nurses in 52 hospitals in China on mastery of knowledge about skin injury in the elderly based on the background of mixed-mode homogenization training.Methods:Using the convenient sampling method, a total of 1 067 nurses from 52 hospitals in China were selected as the research objects in January 2021. A self-designed questionnaire on knowledge of skin injury in the elderly was used to investigate the nurses through the questionnaire star and univariate analysis was used to analyze the influencing factors. A total of 1 067 questionnaires were distributed and 1 067 valid questionnaires were recovered, and the effective recovery rate was 100%.Results:The knowledge scores of pressure injury, incontinence-associated dermatitis, skin tear and xerosis cutis among 1067 nurses were (95.66±7.37) , (95.65±9.15) , (91.37±15.45) and (87.67±15.91) , respectively. The results of univariate analysis showed that hospital grade was the influencing factor of nurses' knowledge score of pressure injury, skin tear and incontinence-associated dermatitis ( P<0.05) , educational background was the influencing factor of nurses' knowledge score of skin tear ( P<0.05) , professional title was the influencing factor of nurses' knowledge scores of pressure injury, incontinence-associated dermatitis and xerosis cutis ( P<0.05) . Conclusions:Hospitals at all levels need to strengthen the theoretical and practical knowledge training for nurses on skin xerosis and skin tear in the elderly, especially for nurses with primary titles and lower education in grassroots hospitals.