Objective:To investigate humoral and antigen-specific T cell immune responses induced by oral administration of WGP-OVA in C57BL/6 mice.Methods:C57BL/6 mice were orally administered with PBS,WGP and WGP-OVA for 17 days,respec-tively.The serum immunoglobulin levels including IgG1,IgG2a,IgG3 and IgM of mice were detected using LEGENDplexTM Multi-An-alyte Flow Assay Kit.HE staining was used to compare the size of lymphoid nodules in spleens.FACS was used to analyze the percent-age of F4/80+macrophages and F4/80+SIINFEKL+macrophages in inguinal lymph nodes(ILNs).In addition,the T cell-mediated im-munity stimulated by the WGP-OVA oral vaccine was analyzed by ILNs-infiltrating antigen-specific CD8+T cell using MHC Tetramer assay.Results:Oral administration of WGP-OVA significantly increased the contents of IgG1,IgG2a,IgG3 and IgM in the serum,and enlarged the lymphoid nodules in spleens,compared to those orally administered with PBS.Oral administration of WGP-OVA pro-moted the ILNs-infiltration of F4/80+macrophages,and enhanced the antigen-presentation of OVA in macrophages in ILNs.Moreover,the expansion of OVA specific CD8+CTLs in ILNs was also stimulated by WGP-OVA.Conclusion:WGP-OVA involved in both the humoral and antigen-specific T cell immune responses in C57BL/6 mice.

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 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.

Objective:To investigate the application effect of the blended teaching model of "pre-class synchronous small private online course (SPOC)+ flipped classroom+post-class knowledge expansion" in the theoretical teaching of biochemistry and molecular biology. Methods:A total of 951 students majoring in clinical medicine, preventive medicine, and pharmacy in the class of 2020 in Qiqihar Medical College were selected as teaching reform research group (experimental group), and their curriculum relied on the self-built massive open online course (MOOC) curriculum and the MOOC resources of Chinese universities to construct a blended teaching model; the reform methods such as small class grouping, case-based learning, and diversified examination were adopted to carry out theoretical flipped teaching activities with cross integration of cases and knowledge points as the main line. A total of 847 students majoring in clinical medicine, preventive medicine, and pharmacy in the class of 2019 were selected as control group, and the traditional teaching method was used for theoretical courses. The courses were evaluated by offline assessment and online assessment, and feedback information was collected through examination scores, questionnaire survey, and online voting. SPSS 20.0 was used for statistical analysis, and the t-test was used for comparison between groups. Results:The experimental group had a significantly higher total score of final examination than the control group [(92.12±3.88) vs. (86.73±5.27), P<0.05]. The questionnaire survey showed that the students in the experimental group showed a relatively high degree of satisfaction with the blended teaching reform, which increased their participation, experiencing, and sharing activities. The students majoring in clinical medicine in the class of 2020 believed that they had established clinical thinking ability (263, 92.61%) and become familiar with the clinical manifestations and pathogenesis of common diseases (262, 92.25%); the students majoring in preventive medicine in the class of 2020 believed that they had increased their awareness of serving the public (151, 93.21%) and developed the ability to teach and guide healthy living (148, 91.36%); the students majoring in pharmacy in the class of 2020 believed that they had mastered the mechanism of action of drugs for disease treatment (138, 93.24%) and understood the importance of rational drug use in clinical practice (135, 91.22%). Conclusion:The blended teaching model realizes student-centered teaching, stimulates the interest and initiative in learning, and improves learning outcome, thereby improving teaching quality to a certain extent.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical bacterial isolates from bloodstream infections in China in 2021.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2021 to December 2021. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical Laboratory Standards Institute (CLSI). WHONET 5.6 was used to analyze data.Results:During the study period, 11 013 bacterial strains were collected from 51 hospitals, of which 2 782 (25.3%) were Gram-positive bacteria and 8 231 (74.7%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (37.6%), Klebsiella pneumoniae (18.9%), Staphylococcus aureus (9.8%), coagulase-negative Staphylococci (6.3%), Pseudomonas aeruginosa (3.6%), Enterococcus faecium (3.6%), Acinetobacter baumannii (2.8%), Enterococcus faecalis (2.7%), Enterobacter cloacae (2.5%) and Klebsiella spp (2.1%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus aureus were 25.3% and 76.8%, respectively. No glycopeptide- and daptomycin-resistant Staphylococci was detected; more than 95.0% of Staphylococcus aureus were sensitive to ceftobiprole. No vancomycin-resistant Enterococci strains were detected. The rates of extended spectrum B-lactamase (ESBL)-producing isolated in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were 49.6%, 25.5% and 39.0%, respectively. The prevalence rates of carbapenem-resistance in Escherichia coli and Klebsiella pneumoniae were 2.2% and 15.8%, respectively; 7.9% of carbapenem-resistant Klebsiella pneumoniae was resistant to ceftazidime/avibactam combination. Ceftobiprole demonstrated excellent activity against non-ESBL-producing Escherichia coli and Klebsiella pneumoniae. Aztreonam/avibactam was highly active against carbapenem-resistant Escherichia coli and Klebsiella pneumoniae. The prevalence rate of carbapenem-resistance in Acinetobacter baumannii was 60.0%, while polymyxin and tigecycline showed good activity against Acinetobacter baumannii (5.5% and 4.5%). The prevalence of carbapenem-resistance in Pseudomonas aeruginosa was 18.9%. Conclusions:The BRICS surveillance results in 2021 shows that the main pathogens of blood stream infection in China are gram-negative bacteria, in which Escherichia coli is the most common. The MRSA incidence shows a further decreasing trend in China and the overall prevalence of vancomycin-resistant Enterococci is low. The prevalence of Carbapenem-resistant Klebsiella pneumoniae is still on a high level, but the trend is downwards.

Objective:To investigate the effect of tripartite motif-containing 23 (Trim23) on the differentiation and maturation of dendritic cells and the possible mechanism.Methods:Mouse bone marrow-derived dendritic cells (BMDCs) were prepared from bone marrow cells of C57BL/6 mice with the presence of Flt3L. Real-time quantitative PCR and Western blot were used to detect the expression of Trim23 in BMDCs after LPS stimulation. An overexpression vector for full-length Trim23 (Trim23 OE) was constructed and transfected into BMDCs, and the pcDNA3.1 empty vector was used as control. Flow cytometry was used to detect the expression of CD80, CD86, CD40 and MHCⅡ on the surface of vector-transfected BMDCs after LPS stimulation and ELISA was used to detect the secretion of IL-12p40, TNF-α, IL-6 and IL-10 by these cells. CD8 + and CD4 + T cells were isolated from spleen and lymph nodes of OT-Ⅰ and OT-Ⅱ mice by magnetic beads and co-cultured with LPS-treated BMDCs in the presence of ovalbumin (OVA). Flow cytometry was used to detect the proliferation and differentiation of CD8 + and CD4 + T cells. Western blot was performed to analyze the phosphorylation of p38, ERK1/2 and AKT in BMDCs. Two overexpression vectors for Trim23 mutants lacking RING or ARF domain (Trim23 ΔRING and Trim23 ΔARF) were constructed and transfected into BMDCs. Then flow cytometry and ELISA were used to detect the expression of surface molecules and cytokines. Results:The expression of Trim23 in BMDCs was significantly down-regulated after LPS stimulation. The expression of MHCⅡ, CD86 and CD80 and the secretion of TNF-α and IL-6 decreased significantly in BMDCs overexpressing Trim23. Furthermore, overexpression of Trim23 inhibited the ability of BMDCs to induce the proliferation and differentiation of CD4 + T cells and the proliferation of CD8 + T cells. Western blot showed that the phosphorylation of p38 and ERK1/2 decreased significantly in Trim23-overexpressing BMDCs. Compared with wildtype Trim23, overexpression of Trim23 ΔRING had no significant influence on the expression of surface molecules (MHCⅡ and CD86) and the secretion of cytokines (TNF-α and IL-6) in BMDCs stimulated by LPS. Conclusions:Trim23 overexpression inhibited the maturation and immune activation of BMDCs via MAPK signal pathway and its RING domain. This study provided reference for targeting Trim23 to improve the immune response of dendritic cell-based tumor vaccines.

Objective:To observe the long-term efficacy and late adverse reactions of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for mediastinal lymph node recurrence after radical surgery for esophageal squamous cell carcinoma (ESCC).Methods:A total of 20 ESCC patients with mediastinal lymph node recurrence (≤5) after radical surgery admitted to Department of Radiotherapy, Shanghai Ruijin Hospital between June 2019 and December 2021 were enrolled in this prospective study. Among them, 10 patients were enrolled in phase I study and 10 patients in phase II study. Four, 3 and 13 patients received three different doses of SIB-IMRT at 58.8 Gy/28 fractions, 64.4 Gy/28 fractions and 70.0 Gy/28 fractions for recurrent lesions, respectively. The overall survival (OS) rate, local control rate (LCR) and progression-free survival (PFS) were calculated by Kaplan-Meier analysis. Adverse reactions were also analyzed.Results:The most common sites of recurrence were 2R and 4 L, accounting for 35% and 25%, respectively. The median follow-up time was 32 months. For patients who received salvage chemoradiation after relapse, the 1-, 2- and 3-year OS rates were 100%, 88% and 78%, the 1-, 2- and 3-year PFS rates were 85%, 78% and 78%, respectively. The most common hematological toxicities were leukocytopenia and anemia. The most common nonhematological toxicity was esophagitis. However, no grade 3 or above esophagitis, pneumonia and cardiotoxicity were found. Three patients who received SIB-IMRT at 58.8 Gy/28 fractions died of distant metastases at 2 years after treatment, and 1 patient who received SIB-IMRT at 70.0 Gy/28 fractions died of distant metastases at 16 months after treatment.Conclusion:Salvage chemoradiotherapy using SIB-IMRT is efficacious and safe for mediastinal lymph node recurrence in ESCC patients after radical resection.

Objective:To investigate the bacterial composition and antimicrobial resistance profile of clinical isolates from bloodstream infections in China.Methods:The clinical bacterial strains isolated from blood culture were collected during January 2020 to December 2020 in member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS). Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical Laboratory Standards Institute(CLSI, USA). WHONET 5.6 was used to analyze data.Results:During the study period, 10 043 bacterial strains were collected from 54 hospitals, of which 2 664 (26.5%) were Gram-positive bacteria and 7 379 (73.5%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (38.6%), Klebsiella pneumoniae (18.4%), Staphylococcus aureus (9.9%), coagulase-negative Staphylococci (7.5%), Pseudomonas aeruginosa (3.9%), Enterococcus faecium (3.3%), Enterobacter cloacae (2.8%), Enterococcus faecalis (2.6%), Acinetobacter baumannii (2.4%) and Klebsiella spp (1.8%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus aureus were 27.6% and 74.4%, respectively. No glycopeptide- and daptomycin-resistant Staphylococci were detected. More than 95% of Staphylococcus aureus were sensitive to rifampicin and SMZco. No vancomycin-resistant Enterococci strains were detected. Extended spectrum β-lactamase (ESBL) producing Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were 48.4%, 23.6% and 36.1%, respectively. The prevalence rates of carbapenem-resistance in Escherichia coli and Klebsiella pneumoniae were 2.3% and 16.1%, respectively; 9.6% of carbapenem-resistant Klebsiella pneumoniae strains were resistant to ceftazidime/avibactam combination. The prevalence rate of carbapenem-resistance in Acinetobacter baumannii was 60.0%, while polymyxin and tigecycline showed good activity against Acinetobacter baumannii. The prevalence rate of carbapenem-resistance of Pseudomonas aeruginosa was 23.2%. Conclusions:The surveillance results in 2020 showed that the main pathogens of bloodstream infection in China were gram-negative bacteria, while Escherichia coli was the most common pathogen, and ESBL-producing strains declined while carbapenem-resistant Klebsiella pneumoniae kept on high level. The proportion and the prevalence of carbapenem-resistant Pseudomonas aeruginosa were on the rise slowly. On the other side, the MRSA incidence got lower in China, while the overall prevalence of vancomycin-resistant Enterococci was low.

Objective:To investigate the distribution and antimicrobial resistance profile of clinical bacteria isolated from blood culture in China.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2016 to December 2017. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by US Clinical and Laboratory Standards Institute (CLSI) 2019. WHONET 5.6 was used to analyze data.Results:During the study period, 8 154 bacterial strains were collected from 33 hospitals, of which 2 325 (28.5%) were Gram-positive bacteria and 5 829 (71.5%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (34.7%), Klebsiella pneumoniae (15.8%), Staphylococcus aureus (11.3%), coagulase-negative Staphylococci (7.4%), Acinetobacter baumannii (4.6%), Pseudomonas aeruginosa (3.9%), Enterococcus faecium (3.8%), Streptococci (2.9%), Enterobacter cloacae (2.7%) and Enterococcus faecalis (2.5%). Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus (MRCNS) accounted for 34.2%(315/922) and 77.7%(470/605), respectively. No vancomycin-resistant Staphylococcus was detected. The resistance rate of Enterococcus faecium to vancomycin was 0.6%(2/312), and no vancomycin-resistant Enterococcus faecium was detected. The ESBLs-producing rates in Escherichia coli, Klebsiella pneumoniae and Proteus were 55.7%(1 576/2 831), 29.9%(386/1 289) and 38.5%(15/39), respectively. The incidences of carbapenem-resistance in Escherichia coli, Klebsiella pneumoniae were 1.2%(33/2 831), 17.5%(226/1 289), respectively. The resistance rates of Acinetobacter baumannii to polymyxin and tigecycline were 14.8%(55/372) and 5.9%(22/372) respectively, and those of Pseudomonas aeruginosa to polymyxin and carbapenem were 1.3%(4/315) and 18.7%(59/315), respectively. Conclusion:The surveillance results from 2016 to 2017 showed that the main pathogens of blood stream infection in China were gram-negative bacteria, while Escherichia coli was the most common pathogen; the MRSA incidence was lower than other surveillance data in the same period in China; carbapenem-resistant Escherichia coli was at a low level during this surveillance, while carbapenem-resistant Klebsiella pneumoniae is on the rise.

OBJECTIVE：To study the effects of gin seng root extract on autophagy ，proliferation and cytokine of splenic lymphocyte of mice ，and to study its mechanism. METHODS ：The splenic lymphocyte of mice were divided into blank control group，positive control group （concanavalin A ，5 μg/mL），different concentration of ginseng root extract groups （32，125，500 μg/mL，by lyophilized powder ）. After 48 h of culture with the corresponding medicine ，acridine orange staining method was used to detect autophagy of splenic lymphocyte ；CCK-8 assay was used to detect the cell proliferation ；ELISA assay was used to determine the levels of IL- 4，IL-6 and TNF-α in cell culture；Western blotting method was used to detect the expression of LC 3B and Beclin- 1，as well as the phosphorylation of AMPK ，AKT and mTOR. RESULTS ：Compared with blank control group ，32， 125，500 μg/mL ginseng root extract could increase the number of acidic autophagosomes in splenic lymphocytes of mice（P＜0.05 or P＜0.01）；125，500 μg/mL Ginseng root extract could significantly enhance the survival rate of splenic lymphocytes，the levels of IL- 4，IL-6 and TNF-α and the transformation of LC3BⅠ to LC 3BⅡ，significantly increased the protein expression of Beclin- 1， quinacrine cationic liposomes for treating non-small cell @163.com lung cancer[J]. J Drug Target ，2015，23（3）：232-243. the phosphorylation of AMPK protein ，and significantly reduced the phosphorylation level of AKT and mTOR proteins ，with statistical significance （P＜0.05 or P＜0.01）. CONCLUSIONS ：Ginseng root extract can induce autophagy of mice splenic lymphocytes，activate the activity of splenic lymphocytes ，regulate the secretion of cytokine by activating AMPK and inhibiting the activation of AKT which can inhibit the activity of mTOR ，so as to exert immune enhancement effect.