ObjectiveTo explore the characteristics of ecological niche and interspecific relationships of mosquitoes in different habitats in Dongcheng District, Beijing, and to provide a basis for mosquito ecological monitoring, control and the development or optimization of prevention and control strategies for related mosquito-borne diseases. MethodsFrom May to October 2023, the ecological monitoring in residential areas, parks, tourist attractions and medical institutions in Dongcheng District of Beijing was carried out using the carbon dioxide (CO₂) mosquito trapping method, and the ecological niche characteristics and interspecific relationships of mosquitoes in different habitats were analyzed using Levins ecological niche breadth index, Pinaka ecological niche overlap index and ecological niche similarity coefficients. ResultsThe temporal ecological niche of Culex pipiens pallens (10.62) was higher than that of Aedes albopictus (8.29) in different habitats in Dongcheng District of Beijing, and the temporal ecological niche overlap index of the two mosquitoes was as high as 0.87. The ecological niche breadth of Culex pipiens pallens was higher than that of Aedes albopictus in different monitoring habitats, and the order of the ecological niche breadth of Culex pipiens pallens in different monitoring habitats was, from high to low, as follows: residential areas (11.09) > tourist attractions (10.25) > medical institutions (9.15) > parks (9.07), while the ecological niche breadth of Aedes albopictus in different habitats was, in descending order, residential areas (8.56) > medical institutions (7.68) > parks (7.44) > tourist attractions (5.73). The results of niche overlap analysis showed that the overlap index between Culex pipiens pallens and Aedes albopictus was the largest in residential areas (0.86), as for in other habitats, which was, in descending order, parks (0.81) > medical institutions (0.68) > tourist attractions (0.60). Besides, the ecological similarity coefficients further verified that similarity coefficients, between the two mosquito species, were highest in residential areas (0.712), lowest in tourist attractions (0.497), and which were 0.675 in parks and 0.598 in medical institutions, respectively. ConclusionIn different monitoring habitats in Dongcheng District of Beijing, Culex albopictus pallens demonstrates a stronger spatio-temporal resource utilization ability than Aedes albopictus, and the two species exhibit more similar spatio-temporal resource utilization patterns in residential areas. Corresponding control strategies targeting the characteristics of ecological niches and interspecific relationships of these two mosquito species in different habitats should be developed to enhance the prevention and control effect.

Chronic liver disease remains a severe threat to human health. Furthermore, if left untreated promptly and effectively, it may gradually develop into end-stage liver disease, including decompensated cirrhosis and liver failure. Currently, mesenchymal stem cell technology is acting as a kind of an emerging treatment method, and multiple clinical trials have confirmed its promising application prospects in the treatment of decompensated cirrhosis and liver failure. Hence, stem cell therapy may offer a novel therapeutic option for these patients. This article summarizes the clinical research progress of stem cell therapy for decompensated cirrhosis and liver failure and analyzes present challenges and application prospects.

Objective:To develop and validate artificial intelligence (AI) models based on deep learning for precise boundary identification of early gastric cancer (EGC) in narrow-band imaging (NBI) and near focus narrow-band imaging (NF-NBI) endoscopic images.Methods:Endoscopic submucosal dissection (ESD) images from 282 patients diagnosed as having EGC by postoperative pathology at the Department of Gastroenterology, the First Affiliated Hospital of Soochow University were retrospectively collected from February 2016 to June 2024. The images were randomly divided into the training set and the validation set at an approximate 8∶2 ratio. In the NBI modality, 980 images from 171 patients were used for training, 235 images from 61 patients were used for validation. In the NF-NBI modality, 1 273 images from 128 patients were used for training, and 373 images from 35 patients were used for validation. This study trained a total of six convolutional neural network (CNN) models: two independent CNN1 models, two independent CNN2 models, and two fused CNN3 models. Using expert-delineated EGC boundaries based on post-ESD pathological findings as the gold standard, the intersection over union (IOU) value of the CNN3 models was compared against junior (<5 years experience), mid-level (5-10 years), and senior (>10 years) endoscopists.Results:In NBI validation set, the IOU value of CNN3 model was significantly higher than that of junior (0.732 VS 0.489, Z=11.528, P<0.001) and mid-level endoscopists (0.732 VS 0.521, Z=11.184, P<0.001). However, no significant difference was observed between CNN3 model and senior endoscopists (0.732 VS 0.739, Z=0.593, P=0.554). Similarly, in NF-NBI validation set, CNN3 model outperformed junior (0.757 VS 0.537, Z=15.944, P<0.001) and mid-level endoscopists (0.757 VS 0.597, Z=9.722, P<0.001), while matching senior endoscopists (0.757 VS 0.769, Z=0.854, P=0.394). Conclusion:The fused CNN3 model achieves senior expert-level accuracy in delineating EGC boundaries in both NBI and NF-NBI images, demonstrating potential to assist less-experienced endoscopists in precise identification of EGC boundaries.

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.

Chronic liver disease remains a severe threat to human health. Furthermore, if left untreated promptly and effectively, it may gradually develop into end-stage liver disease, including decompensated cirrhosis and liver failure. Currently, mesenchymal stem cell technology is acting as a kind of an emerging treatment method, and multiple clinical trials have confirmed its promising application prospects in the treatment of decompensated cirrhosis and liver failure. Hence, stem cell therapy may offer a novel therapeutic option for these patients. This article summarizes the clinical research progress of stem cell therapy for decompensated cirrhosis and liver failure and analyzes present challenges and application prospects.

Objective:To develop and validate artificial intelligence (AI) models based on deep learning for precise boundary identification of early gastric cancer (EGC) in narrow-band imaging (NBI) and near focus narrow-band imaging (NF-NBI) endoscopic images.Methods:Endoscopic submucosal dissection (ESD) images from 282 patients diagnosed as having EGC by postoperative pathology at the Department of Gastroenterology, the First Affiliated Hospital of Soochow University were retrospectively collected from February 2016 to June 2024. The images were randomly divided into the training set and the validation set at an approximate 8∶2 ratio. In the NBI modality, 980 images from 171 patients were used for training, 235 images from 61 patients were used for validation. In the NF-NBI modality, 1 273 images from 128 patients were used for training, and 373 images from 35 patients were used for validation. This study trained a total of six convolutional neural network (CNN) models: two independent CNN1 models, two independent CNN2 models, and two fused CNN3 models. Using expert-delineated EGC boundaries based on post-ESD pathological findings as the gold standard, the intersection over union (IOU) value of the CNN3 models was compared against junior (<5 years experience), mid-level (5-10 years), and senior (>10 years) endoscopists.Results:In NBI validation set, the IOU value of CNN3 model was significantly higher than that of junior (0.732 VS 0.489, Z=11.528, P<0.001) and mid-level endoscopists (0.732 VS 0.521, Z=11.184, P<0.001). However, no significant difference was observed between CNN3 model and senior endoscopists (0.732 VS 0.739, Z=0.593, P=0.554). Similarly, in NF-NBI validation set, CNN3 model outperformed junior (0.757 VS 0.537, Z=15.944, P<0.001) and mid-level endoscopists (0.757 VS 0.597, Z=9.722, P<0.001), while matching senior endoscopists (0.757 VS 0.769, Z=0.854, P=0.394). Conclusion:The fused CNN3 model achieves senior expert-level accuracy in delineating EGC boundaries in both NBI and NF-NBI images, demonstrating potential to assist less-experienced endoscopists in precise identification of EGC boundaries.

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.