Salmonella has demonstrated considerable potential as a vaccine vector,exhibiting robust immunogenicity,ease of oral administration,and cost-effective production.Live attenuated Salmo-nella carrying heterologous antigens can induce both localized mucosal immunity and systemic a-daptive immune responses in hosts after successfully reaching the intestinal tract via oral delivery.Recent advances such as permanent deletion of virulence genes,regulated-delayed attenuation and lysis systems,have initially achieved a balance between the safety and immunogenicity of these vaccine platforms.Nevertheless,practical applications of such vaccine vectors remain constrained by challenges related to gastrointestinal barrier obstruction,inefficient antigen delivery,and im-mune tolerance.With the rapid advancement of multidisciplinary technologies,these limitations are anticipated to be progressively addressed.This review presented a comprehensive summary and dis-cussion of the immune mechanisms,development strategies,current applications,advantages,and challenges associated with oral live attenuated Salmonella vaccine vectors.It also delineated the fu-ture direction of research and development,with a view to providing theoretical references for re-lated research.

Salmonella has demonstrated considerable potential as a vaccine vector,exhibiting robust immunogenicity,ease of oral administration,and cost-effective production.Live attenuated Salmo-nella carrying heterologous antigens can induce both localized mucosal immunity and systemic a-daptive immune responses in hosts after successfully reaching the intestinal tract via oral delivery.Recent advances such as permanent deletion of virulence genes,regulated-delayed attenuation and lysis systems,have initially achieved a balance between the safety and immunogenicity of these vaccine platforms.Nevertheless,practical applications of such vaccine vectors remain constrained by challenges related to gastrointestinal barrier obstruction,inefficient antigen delivery,and im-mune tolerance.With the rapid advancement of multidisciplinary technologies,these limitations are anticipated to be progressively addressed.This review presented a comprehensive summary and dis-cussion of the immune mechanisms,development strategies,current applications,advantages,and challenges associated with oral live attenuated Salmonella vaccine vectors.It also delineated the fu-ture direction of research and development,with a view to providing theoretical references for re-lated research.

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 evaluate the safety and efficacy of accelerator-based boron neutron capture therapy (AB-BNCT) in the treatment of recurrent and refractory malignant tumors.Methods:The data of 14 patients admitted to Xiamen Humanity Hospital from September 2022 to April 2023 were prospectively collected, including 7 patients with primary brain malignancies and 7 patients with locally recurrent inoperable head and neck malignancies. All patients received intravenous infusion of boron drug (NBB-001, p-dihydroxyborylphe nylalanine, a patented freeze-dried formulation) at a total nominal dosage of 500 mg/kg (11 patients) or 750 mg/kg (3 patients), and were irradiated with neutrons (operating with NeuPex system). Adverse events after treatment were recorded and assessed. The primary efficacy endpoint was the 90 d objective response rate (ORR), while the secondary endpoints included progression-free survival (PFS) and complete response rate (CRR). Data were compiled and analyzed by SAS 9.4 software. The rate and 95% CI were calculated using Clopper-Pearson method. Results:The median dose delivered to 80% of the target volume (D 80%) was 16.80 GyE (range: 8.93-23.79 GyE). The most common adverse reactions were hyperamylasemia, alopecia, and hyperprolactinemia. Five patients experienced 8 cases of grade 3 or above adverse events, including 1 case of grade 4 acute kidney injury and 7 cases of grade 3 adverse events. All adverse events were recovered after observation or treatment. At 90 d after treatment, the ORR of all patients was 9/14 (64%, 95% CI: 35%-87%), disease control rate (DCR) was 10/14 (71%, 95% CI: 42%-92%), CRR was 2/14 (14%, 95% CI: 2%-42%); and the best overall response during the entire course included an ORR of 10/14 (71% ,95% CI: 42%-92%), DCR of 13/14 (93%, 95% CI: 66%-100%), and CRR of 3/14 (21% ,95% CI: 5%-51%). The 1-year survival rate for head and neck malignancies was 71.4%, and the 2-year survival rate was 42.8%. The 1-year survival rate for recurrent brain malignancies was 42.8%. Conclusion:AB-BNCT demonstrates favorable safety and promising efficacy in treating primary brain malignancies and recurrent/refractory head and neck malignancies, representing a potential therapeutic option.

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 evaluate the safety and efficacy of accelerator-based boron neutron capture therapy (AB-BNCT) in the treatment of recurrent and refractory malignant tumors.Methods:The data of 14 patients admitted to Xiamen Humanity Hospital from September 2022 to April 2023 were prospectively collected, including 7 patients with primary brain malignancies and 7 patients with locally recurrent inoperable head and neck malignancies. All patients received intravenous infusion of boron drug (NBB-001, p-dihydroxyborylphe nylalanine, a patented freeze-dried formulation) at a total nominal dosage of 500 mg/kg (11 patients) or 750 mg/kg (3 patients), and were irradiated with neutrons (operating with NeuPex system). Adverse events after treatment were recorded and assessed. The primary efficacy endpoint was the 90 d objective response rate (ORR), while the secondary endpoints included progression-free survival (PFS) and complete response rate (CRR). Data were compiled and analyzed by SAS 9.4 software. The rate and 95% CI were calculated using Clopper-Pearson method. Results:The median dose delivered to 80% of the target volume (D 80%) was 16.80 GyE (range: 8.93-23.79 GyE). The most common adverse reactions were hyperamylasemia, alopecia, and hyperprolactinemia. Five patients experienced 8 cases of grade 3 or above adverse events, including 1 case of grade 4 acute kidney injury and 7 cases of grade 3 adverse events. All adverse events were recovered after observation or treatment. At 90 d after treatment, the ORR of all patients was 9/14 (64%, 95% CI: 35%-87%), disease control rate (DCR) was 10/14 (71%, 95% CI: 42%-92%), CRR was 2/14 (14%, 95% CI: 2%-42%); and the best overall response during the entire course included an ORR of 10/14 (71% ,95% CI: 42%-92%), DCR of 13/14 (93%, 95% CI: 66%-100%), and CRR of 3/14 (21% ,95% CI: 5%-51%). The 1-year survival rate for head and neck malignancies was 71.4%, and the 2-year survival rate was 42.8%. The 1-year survival rate for recurrent brain malignancies was 42.8%. Conclusion:AB-BNCT demonstrates favorable safety and promising efficacy in treating primary brain malignancies and recurrent/refractory head and neck malignancies, representing a potential therapeutic option.

Objective:To analyze the immediate risk and 5-year cumulative risk of high-grade cervical lesions in high-risk human papillomavirus(Hr-HPV)positive patients with minor cytological abnormalities and to validate the local applicability of clinical management strategies in the 2019 American Society for Colposcopy and Cervical Pathology Guidelines.Methods:A total of 565 patients with positive Hr-HPV,cytology result of atypical squamous cells of undetermined significance(ASC-US)or low-grade squamous intraepithelial lesion(LSIL)and also under-went colposcopy and biopsy were selected from the gynecological clinic of Peking Union Medical College Hospital from February 2017 to November to analyze the immediate risk of high-grade cervical lesions(CIN2 and above).Besides,a total of 193 patients with histological results of CIN1 or below and 5-year follow-up data available were further analyzed for the 5-year cumulative risk of high-grade cervical lesions.Results:①In the 565 patients,the immediate incidence of CIN2+and CIN3+was 32.21%and 12.39%,respectively.Multivariate Logistic regression showed that the immediate risk of CIN2+in the LSIL group(35.54%)was 1.62 times that in the ASC-US group(28.78%)(95%CI 1.12-2.36,P＜0.05);the immediate risk of CIN2+in HPV 16/18+group(45.29%)was 2.89 times that in Hr-HPV other+group(23.68%)(95%CI 1.99-4.20,P＜0.05).② Among 193 patients with 5-year long-term follow-up,the 5-year cumulative incidence of CIN2+and CIN3+was 6.2%and 2.6%,respectively.Cox regression analysis results showed that there were no statistically significant differences in 5-year cumulative risk of CIN2+and CIN3+among different ages,Hr-HPV infection types and cytological results(P＞0.05).Conclu-sions:LSIL had a higher detection rate of CIN2+than ASC-US patients only in the first colposcopy biopsy;the immediate risk of high-grade cervical lesion was significantly higher in HPV16/18+patients than in Hr-HPV oth-er+patients,but no significant difference in the 5-year cumulative incidence of high-grade lesions after colposco-py was found.Age was not an independent risk factor for the development of high-grade lesions.

Objective:To analyze the immediate risk and 5-year cumulative risk of high-grade cervical lesions in high-risk human papillomavirus(Hr-HPV)positive patients with minor cytological abnormalities and to validate the local applicability of clinical management strategies in the 2019 American Society for Colposcopy and Cervical Pathology Guidelines.Methods:A total of 565 patients with positive Hr-HPV,cytology result of atypical squamous cells of undetermined significance(ASC-US)or low-grade squamous intraepithelial lesion(LSIL)and also under-went colposcopy and biopsy were selected from the gynecological clinic of Peking Union Medical College Hospital from February 2017 to November to analyze the immediate risk of high-grade cervical lesions(CIN2 and above).Besides,a total of 193 patients with histological results of CIN1 or below and 5-year follow-up data available were further analyzed for the 5-year cumulative risk of high-grade cervical lesions.Results:①In the 565 patients,the immediate incidence of CIN2+and CIN3+was 32.21%and 12.39%,respectively.Multivariate Logistic regression showed that the immediate risk of CIN2+in the LSIL group(35.54%)was 1.62 times that in the ASC-US group(28.78%)(95%CI 1.12-2.36,P＜0.05);the immediate risk of CIN2+in HPV 16/18+group(45.29%)was 2.89 times that in Hr-HPV other+group(23.68%)(95%CI 1.99-4.20,P＜0.05).② Among 193 patients with 5-year long-term follow-up,the 5-year cumulative incidence of CIN2+and CIN3+was 6.2%and 2.6%,respectively.Cox regression analysis results showed that there were no statistically significant differences in 5-year cumulative risk of CIN2+and CIN3+among different ages,Hr-HPV infection types and cytological results(P＞0.05).Conclu-sions:LSIL had a higher detection rate of CIN2+than ASC-US patients only in the first colposcopy biopsy;the immediate risk of high-grade cervical lesion was significantly higher in HPV16/18+patients than in Hr-HPV oth-er+patients,but no significant difference in the 5-year cumulative incidence of high-grade lesions after colposco-py was found.Age was not an independent risk factor for the development of high-grade lesions.