Objective To investigate the distribution characteristics of Klebsiella pneumoniae(KP),hyperviru-lent Klebsiella pneumoniae(hvKP),carbapenem-resistant Klebsiella pneumoniae(CRKP),and hypervirulent car-bapenem-resistant Klebsiella pneumoniae(hv-CRKP/CR-hvKP)in the environment of general intensive care unit(ICU)at medical institutions,and provide reference for environment assessment as well as healthcare-associated in-fection(HAI)prevention and control in ICU.Methods A total of 3 336 environmental specimens were collected from general ICUs of medical institutions in Shanghai in 2019 and 2023.After strain isolation,antimicrobial suscep-tibility testing and whole genome sequencing were conducted.Results The detection rate of KP was 1.59％(n=53),among which hvKP,CRKP,and hv-CRKP/CR-hvKP accounted for 37.74％(20/53),52.83％(28/53),and 24.53％(13/53)of the total detected strains,respectively.The main types of hvKP were ST11-KL64 and ST11-KL25,CRKP were ST15-KL19 and ST11-KL25,hv-CRKP/CR-hvKP were ST11-KL25 and ST11-KL64.The main carried resistance genes included fosA,oqx AB,tet(A),blaTEM-1B,blaKPC-2,qnrS11,etc.All strains carried viru-lence genes fimH,iutA,ent A,entB,entC,entD,entE,and entF,with only one strain carrying rmp A gene.Conclusion KP contamination is widespread in general ICU environment of medical institutions,predominantly ST11 and ST15,presenting a polymorphic distribution.CRKP and hvKP account for a relatively high proportion,and multidrug resistance is serious.Co-evolution of drug resistance and virulence presents in KP,and poses signifi-cant infection and pathogenic risks to patients,necessitating enhanced clinical vigilance and preparedness for poten-tial outbreaks.

Objective:To understand the etiological surveillance and drug resistance characteristics of Legionella pneumophila (LP) from the aqueous environment of public places in Shanghai, from 2011 to 2020, and provide evidence for surveillance of the disease. Methods:Environmental water samples were systematically collected from public venues in urban and suburban districts of Shanghai for LP surveillance. All the identified LP isolates underwent a series of testings including serotyping, pulsed field gel electrophoresis (PFGE), sequence-based typing, and antimicrobial susceptibility testing. χ2 test or Cochran-Armitage trend tests were used for statistical analysis and for temporal resistance patterns. Results:Among 6 263 water samples, the LP-positive rate was 20.93% (1 311/6 263). The positivity rate decreased from 24.98% (287/1 149) in 2011-2012 to 20.02% (1 024/5 114) in 2013-2020 ( χ2=13.92, P<0.001), with the highest monthly positivity observed from June to August (23.79%, 745/3 132). A total of 1 365 LP strains were isolated, of which 912 were further characterized, including 10 serotypes, 149 PFGE patterns, and 33 sequence types (ST). The predominant serotype was Lp1 (86.84%, 792/912), and the dominant ST was ST752 (29.50%, 269/912). ST clustering revealed two major clonal groups CG1 and CG2, accounting for 91.12% (831/912) of the isolates. The 190 LPs involved in the drug sensitivity test showed three resistance profiles: azithromycin resistance (31.05%, 59/190), ciprofloxacin resistance (0.53%, 1/190) and azithromycin+ciprofloxacin resistance (0.53%, 1/190). Azithromycin-resistant strains were predominantly ST1 (64.41%, 38/59). The antimicrobial resistance rate showed a significant decline, from 48.65% (18/37) in 2011-2012 to 28.10% (43/153) in 2013-2020 ( χ2=9.38, P=0.002). Conclusions:Compared to from 2011 to 2012, both the positivity rate and antimicrobial resistance prevalence of LP in public aqueous environments of Shanghai exhibited an overall decline from 2013 to 2020. The predominant types of LP were serotype Lp1 and sequence type ST752, with notable high-level resistance to azithromycin. Measures as enhancing the enforcement of water safety regulations and prioritizing surveillance of azithromycin resistance in LP were recommended to mitigate public health risks.

Objective To investigate the distribution characteristics of Klebsiella pneumoniae(KP),hyperviru-lent Klebsiella pneumoniae(hvKP),carbapenem-resistant Klebsiella pneumoniae(CRKP),and hypervirulent car-bapenem-resistant Klebsiella pneumoniae(hv-CRKP/CR-hvKP)in the environment of general intensive care unit(ICU)at medical institutions,and provide reference for environment assessment as well as healthcare-associated in-fection(HAI)prevention and control in ICU.Methods A total of 3 336 environmental specimens were collected from general ICUs of medical institutions in Shanghai in 2019 and 2023.After strain isolation,antimicrobial suscep-tibility testing and whole genome sequencing were conducted.Results The detection rate of KP was 1.59％(n=53),among which hvKP,CRKP,and hv-CRKP/CR-hvKP accounted for 37.74％(20/53),52.83％(28/53),and 24.53％(13/53)of the total detected strains,respectively.The main types of hvKP were ST11-KL64 and ST11-KL25,CRKP were ST15-KL19 and ST11-KL25,hv-CRKP/CR-hvKP were ST11-KL25 and ST11-KL64.The main carried resistance genes included fosA,oqx AB,tet(A),blaTEM-1B,blaKPC-2,qnrS11,etc.All strains carried viru-lence genes fimH,iutA,ent A,entB,entC,entD,entE,and entF,with only one strain carrying rmp A gene.Conclusion KP contamination is widespread in general ICU environment of medical institutions,predominantly ST11 and ST15,presenting a polymorphic distribution.CRKP and hvKP account for a relatively high proportion,and multidrug resistance is serious.Co-evolution of drug resistance and virulence presents in KP,and poses signifi-cant infection and pathogenic risks to patients,necessitating enhanced clinical vigilance and preparedness for poten-tial outbreaks.

Objective:To understand the etiological surveillance and drug resistance characteristics of Legionella pneumophila (LP) from the aqueous environment of public places in Shanghai, from 2011 to 2020, and provide evidence for surveillance of the disease. Methods:Environmental water samples were systematically collected from public venues in urban and suburban districts of Shanghai for LP surveillance. All the identified LP isolates underwent a series of testings including serotyping, pulsed field gel electrophoresis (PFGE), sequence-based typing, and antimicrobial susceptibility testing. χ2 test or Cochran-Armitage trend tests were used for statistical analysis and for temporal resistance patterns. Results:Among 6 263 water samples, the LP-positive rate was 20.93% (1 311/6 263). The positivity rate decreased from 24.98% (287/1 149) in 2011-2012 to 20.02% (1 024/5 114) in 2013-2020 ( χ2=13.92, P<0.001), with the highest monthly positivity observed from June to August (23.79%, 745/3 132). A total of 1 365 LP strains were isolated, of which 912 were further characterized, including 10 serotypes, 149 PFGE patterns, and 33 sequence types (ST). The predominant serotype was Lp1 (86.84%, 792/912), and the dominant ST was ST752 (29.50%, 269/912). ST clustering revealed two major clonal groups CG1 and CG2, accounting for 91.12% (831/912) of the isolates. The 190 LPs involved in the drug sensitivity test showed three resistance profiles: azithromycin resistance (31.05%, 59/190), ciprofloxacin resistance (0.53%, 1/190) and azithromycin+ciprofloxacin resistance (0.53%, 1/190). Azithromycin-resistant strains were predominantly ST1 (64.41%, 38/59). The antimicrobial resistance rate showed a significant decline, from 48.65% (18/37) in 2011-2012 to 28.10% (43/153) in 2013-2020 ( χ2=9.38, P=0.002). Conclusions:Compared to from 2011 to 2012, both the positivity rate and antimicrobial resistance prevalence of LP in public aqueous environments of Shanghai exhibited an overall decline from 2013 to 2020. The predominant types of LP were serotype Lp1 and sequence type ST752, with notable high-level resistance to azithromycin. Measures as enhancing the enforcement of water safety regulations and prioritizing surveillance of azithromycin resistance in LP were recommended to mitigate public health risks.

Objective:To investigate the inhibitory effect of esomeprazole on proliferation and chemosensitizing effect of breast cancer cells.Methods:Human MBA-MD-231, MCF-7 breast cancer cell line and human Huh7 liver cancer cell line were cultured by conventional methods; cells were treated with different concentrations of esomeprazole, and CCK8 kit was used to detect the proliferation of different tumor cells after stimulation. Cells were treated with different concentrations of esomeprazole, and the effects of esomeprazole on cell cycle of different cells were analyzed by flow cytometry. Cells were treated with different concentrations of paclitaxel and epirubicin combined with esomeprazole, and CCK8 kit was used to detect the proliferation of different tumor cells after stimulation. Measurement data were expressed as mean ± standard deviation ( ± s), and analysis of variance was used for comparison among multiple groups. Results:CCK8 results showed that esomeprazole could inhibit the proliferation of MBA-MD-231 cells, MCF-7 cells and Huh7 cells in a dose-dependent manner. Flow cytometry results showed that cells in G 0/G 1 phase were significantly increased by esomeprazole treatment. Esomeprazole can enhance the inhibitory effect of paclitaxel and epirubicin on the proliferation of MBA-MD-231 cells and MCF-7 cells, and improve the chemosensitivity. Conclusion:Esomeprazole blocks breast cancer cell MBA-MD-231, MCF-7 and liver cancer cell Huh7 in G 0/G 1 phase, thereby inhibiting cell proliferation. Esomeprazole can enhance the inhibitory effect of chemotherapeutic drugs on the proliferation of MBA-MD-231 and MCF-7 cells.

Four impurities were isolated from raw material of clindamycin phosphate (CP), and their structures have been determined. LC-MS was used to determine the molecular weights of the impurities in the raw material of CP. Reversed-phase preparative HPLC was used to prepare them, and their chemical structures were identified by HR-MS and NMR. The four unknown impurities were determined as clindamycin-B-phosphate (1), clindamycin-2,4-diphosphate (2), 3',6'-dehydro clindamycin phosphate (3), epi-clindamycin phosphate (4). Impurity 1 has been included in BP and EP, while 2, 3 and 4 have not. The impurities 2, 3, 4 are first separated from raw material of CP.

Rapidly and accurately quantitative analysis of whole-cell sugars in some strains of actinomycetes by GC-MS was performed in this paper. After the polysaccharides were hydrolyzed, deoxidized and esterified , the alditol acetate derivates was analyzed by GC-MS. The derivates of rhamnose, ribose, arabinose , xylose, madurose, mannose, glucose, galactose were separated commendably under this condition. The ratio of the peak area was calculated to get the relative percentage of the various sugars.