1.Comparative Genomic Analysis of Acinetobacter Baumannii from Different Sources in a Tertiary Hospital in Guangzhou
Kang LI ; Yanxian YANG ; Changbu WU ; Li SHAO ; Lanlan ZHONG ; Dingqiang CHEN ; Guobao TIAN
Journal of Sun Yat-sen University(Medical Sciences) 2026;47(3):518-527
ObjectiveTo compare the differences between clinical and environmental sources of Acinetobacter baumannii (AB) at a tertiary hospital in Guangzhou in terms of molecular epidemiological characteristics, antimicrobial resistance, disinfectant tolerance, virulence and the distribution of related genes, as well as plasmid epidemiological characteristics; and to assess the association between environmental and clinical strains and the potential transmission risks associated with environmental contamination. MethodsA total of 118 clinical and 102 environmental AB isolates were collected from a tertiary hospital in Guangzhou between 2024 and 2025. Species identification was performed using mass spectrometry and 16S rRNA sequencing; minimum inhibitory concentrations (MICs) for eight antimicrobial agents were determined using the agar dilution method; biofilm formation capacity was assessed using the crystal violet staining method; A Galleria mellonella infection model was used to evaluate the virulence; whole-genome sequencing was employed for multilocus sequence typing (MLST), phylogenetic analysis, and studies on the distribution of resistance, disinfectant resistance and virulence genes, and plasmid screening. ResultsA total of 38 known ST types were identified among the 220 AB strains, with ST2 and ST40 being the predominant lineages. Antimicrobial susceptibility testing revealed that the clinical infection group exhibited resistance to minocycline, imipenem and other antibiotics, as well as the tolerance levels to the disinfectants triclosan and benzalkonium bromide, were generally higher than those in the environmental group (P<0.001), and the detection rates of drug resistance genes such as blaOXA-23 and adeB all exceeded 70.0%. Statistical analysis confirmed that the MIC values of TCS and BAB were significantly positively correlated with various antibiotic resistance phenotypes (P<0.05). In biofilm experiments, the proportion of strong biofilm-forming strains in the environmental group (64.7%) was significantly higher than that in the clinical infection group (11.9%;χ²=69.06, df=2, P<0.000 1), and the mortality rate of the strains increased with enhanced biofilm-forming ability. Furthermore, a total of 41 plasmid lineages and 219 insertion sequences were detected; ISs such as IS1006 and IS1007 were frequently co-occurring with resistance and virulence genes including blaOXA-23 and katA. ConclusionsThe predominant lineages of AB in this tertiary hospital were ST2 and ST40. The clinical infection group generally exhibits higher levels of antibiotic resistance and tolerance to disinfectants compared to the environmental group, while biofilm-forming ability differs : the environmental group dominates in strong biofilm formation, and the clinical group dominates in weak to moderate biofilm formation. Plasmids and ISs may be involved in the co-occurrence and dissemination control strategies and for the molecular epidemiological surveillance of multidrug-resistant bacteria.
2.Effect of Depression on Bacterial Infection Based on Chronic Unpredictable Mild Stress Model
Lei XU ; Runping ZHAO ; Jieyun CHEN ; Yanxian YANG ; Xilong GUO ; Min DAI ; Guobao TIAN ; Lina QIN
Journal of Sun Yat-sen University(Medical Sciences) 2024;45(4):567-581
[Objective]Depression is a common mental illness with a profound impact on physical health.Depression has been associated with a higher risk of bacterial infection;however,whether this relationship is causal and how depression affects infection remains unclear.Therefore,we aimed to investigate the effects of depressive phenotype in infected mice by constructing a chronic unpredictable mild stress(CUMS)model.[Methods]Mice were induced with CUMS for 4 weeks.The depressive phenotype was evaluated using behavioral tests.Subsequently,the mice were intraperitoneally injected with Klebsiella pneumoniae to establish bacterial infection.Serum and abdominal tissues were collected 48 h after infection.Hematoxylin-eosin(HE)staining was used to observe the pathological changes in the tissues,and enzyme-linked immunosorbent assay(ELISA)was used to measure the levels of inflammatory factors.In addition,the fecal samples collected before infection were analyzed for 16S rDNA gene of gut microbiota,and the expression levels of NF-κB/NLRP3 signaling pathway in colon tissues of uninfected mice were detected.[Results]Behavioral tests showed that compared with the control mice,CUMS mice had significantly lower body weight(P<0.0001,t=5.426),lower sucrose preference rate(P<0.001,t=4.937),increased swimming stationary time(P<0.001,t=16.37),and decreased time spent in the central area of the open field(P<0.01,t=3.575).Survival analysis showed that compared with the control mice,the survival rate of CUMS mice significantly decreased after infection(P<0.05).Additionally,histochemical staining showed that tissue damage in the liver(P<0.05,t=4.025),kidney(P<0.05,t=2.828),and mesentery(P<0.01,t=5.367)significantly increased.Furthermore,ELISA results showed that the levels of the inflammatory cytokines IL-6(P<0.01,t=3.365),IL-1β(P<0.01,t=4.061),TNF-α(P<0.01,t=4.460)and LPS(P<0.0001,t=27.24)were elevated.The difference was statistically significant.According to 16S rDNA sequencing,CUMS-induced changes in the intestinal bacterial community structure of mice,making them significantly different from the control mice.Compared with the control mice,the expression levels of NF-κB(P<0.01,t=6.825)and NLRP3(P<0.001,t=9.561)were upregulated in CUMS mice.[Conclusion]The CUMS model was successfully constructed and CUMS mice developed more severe bacterial infection.Gut microbiota was dysregulated and the expression of NF-κB/NLRP3 signaling pathway was up-regulated in CUMS mice,which was related to the susceptibility to bacterial infection.
3.Analysis of Antibiotics Use Monitoring in 18 Community Hospitals from Shanghai Chongming District during 2016 to 2018
Lyuping HU ; Yanxian NI ; Zhongying YANG ; Bin XU ; Tingting JI
China Pharmacy 2019;30(23):3192-3195
OBJECTIVE: To analyze the application of antibiotics in 18 community health service centers in Shanghai Chongming district, and to further strengthen rational use of antibiotics. METHODS: By retrospective analysis, statistical analysis was made on the monitoring data of antibiotic use and 21 600 prescriptions reported by 18 community health service centers in Chongming district of Shanghai from Jan. 2016 to Dec. 2018 in respect of antibiotics use, top 5 antibiotics in the list of DDDs, prescription analysis, etc. RESULTS: From 2016 to 2018, the average annual total income of medical treatment, drugs and antibiotics of 18 community health service centers in Chongming district of Shanghai were 490 499 000 yuan, 427 231 500 yuan and 41 602 900 yuan respectively. Annual average incomes of outpatient and inpatient antibiotics were 35 435 700 and 6 262 100 yuan. Annual consumption amount of antibiotics were 2 129 627.71 and 70 829.51 DDD. The proportion of antibiotics was 9.76%. Annual antibiotics use density (AUD) was 29.41 DDD. Compound annual growth rate (CAGR) was negative for antibiotics ratio (-3.27%), outpatient antibiotics consumption amount (-18.40%), antibiotics consumption amount for outpatient per time (-17.83%), inpatient antibiotics consumption amourt (-1.25%) and AUD (-0.98%). The dosage form of top 5 antibiotics in the list of DDDs within 3 years were oral preparation, among which cefuroxime, cefaclor, levofloxacin and cefpropene were all ranked in the top five in three years. In 21 600 prescriptions, average number of drug per prescriptions was 1.99, the average amount of prescription was 120 yuan, and the number of antibiotics types used accounted for 8.24% of total drug types; 15.43% of the prescriptions used antibiotics, the average amount of the prescriptions containing antibiotics was 114.46 yuan, and the total amount of antibiotics accounted for 8.24% of the total amount of the prescriptions. CONCLUSIONS: The rational use of antibiotics in Chongming community health service center has been continuously improved, and can provide reference for drug management of primary hospitals.
4.Safety and immunogenicity of influenza vaccine (split virion) in humans
Xue GUO ; Yanli MA ; Yanxian KANG ; Wei JIANG ; Tao JIA ; Xuanwen SHI ; Peng DENG ; Xuemei ZHANG ; Qiong LI ; Ye QIU ; Xiao′ai QIAN ; Haiping CHEN ; Beifang YANG
Chinese Journal of Microbiology and Immunology 2018;38(5):361-365
Objective To evaluate the immunogenicity and safety of a split-virion influenza vac-cine after its manufacturing process was improved. Methods The immunological non-inferiority of trial to control vaccines was evaluated in 240 subjects aged 3-<18 years. Another 360 subjects aged 18-<60 years were randomly divided into three groups that were respectively given three consecutive lots of trail vaccine to assess the consistency of immunogenicity. Results There were 4. 17% of the subjects aged 3-<18 years showed adverse reactions following immunization with trail vaccine and it was not significantly different from that of the control group (P>0. 05). No significant difference in seroconversion rate, geometric mean titer (GMT) of haemagglutination inhibition antibodies(HIAb) or protection rate was found between trial and control groups (P>0. 05). No significant difference in seroconversion rate or HIAb GMT was found among the three lots (P>0. 05). Conclusion The trial influenza vaccine has good safety, immunogenicity and lot-to-lot consistency after the manufacturing process was improved.
5.Correlation of the ultrasonic appearance and pathological/laboratory findings in autoimmune hepatitis
Xi CHEN ; Zhiyan LI ; Lin CHE ; Meng LI ; Yan WANG ; Yanxian ZHOU ; Yang LIU
Chinese Journal of Medical Ultrasound (Electronic Edition) 2018;15(4):263-267
Objective The study was designed to comparatively analyze ultrasonic appearance,laboratory and pathological findings in autoimmune hepatitis(AIH),and their correlation.The clinical value of ultrasound in diagnosing autoimmune hepatitis was studied.Methods By retrospectively reviewing the ultrasonic images,pathological and laboratory results of 68 patients with autoimmune hepatitis admitted to the PLA 302 Hospital from 2014 to 2015,we tried to reveal the correlation between ultrasonic features and pathological and laboratory findings.Results The ultrasonic diagnosis of liver fibrosis was not statistically correlated with the features of pathological ″interface hepatitis″ and serological liver function test.But it was positively correlated with the features of pathological ″spotty necrosis″(r=0.5099,P < 0.001).The ultrasonic features of ″cord-like structure″ and ″nodular change″ had statistically improved the classification of the degree of AIH fibrosis on ultrasonic diagnosis(t=3.9547,P < 0.01).The ultrasonic feature of the change of ″liver size″ and ″morphology″ also have statistically improved the diagnosis of AIH fibrosis with ultrasonography(t=2.070,2.137,4.584,3.773,all P<0.05).Conclusion Ultrasonic images could provide objective evidence in diagnosis of AIH and evaluation of fibrosis degree.
6.Therapeutic effects of sodium nitroprusside combined verapamil for no-reflow during percutaneous coronary intervention
Yingwen CHEN ; Yunzhao HU ; Yanxian WU ; Wensheng LI ; You YANG ; Linlin MAI ; Jiankai ZHONG
Chinese Journal of cardiovascular Rehabilitation Medicine 2017;26(4):416-419
Objective:To explore therapeutic effects of sodium nitroprusside (SNP) combined verapamil on no-reflow during percutaneous coronary intervention (PCI).Methods: A total of 106 patients, who suffered from no-reflow during PCI in our department from Jan 2011 to Dec 2013, were selected.According to random number table method, patients were divided into SNP group (n=55, received SNP based on routine treatment) and combined treatment group (n=51, received verapamil based on SNP group).Cardiac troponin I (cTnI) level before and 16h~18h after PCI, cardiac function indexes after 12-month follow-up, incidence of major adverse cardiovascular events (MACE) were measured and compared between two groups.Results: Compared with before PCI, there were significant rise in cTnI level in both groups on 16~18h after PCI, P=0.001 both;compared with SNP group, there were significant reductions in cTnI level [(1.31±0.44)μg/L vs.(0.11±0.02)μg/L] and percentage of cTnI>0.10μg/L (94.5% vs.54.9%) in combined treatment group, P=0.001 both.Compared with SNP group after 12 months, there was significant rise in left ventricular ejection fraction [(62.29±3.06)% vs.(65.65±3.94)%], and significant reductions in left ventricular end-diastolic dimension[(50.24±3.73)mm vs.(47.60±4.72)mm] and left ventricular end-systolic dimension [(33.29±2.11)mm vs.(31.00±4.33)mm] in combined treatment group, P<0.05 all.There were no significant adverse reactions during hospitalization and follow-up in both groups.Conclusion: When no-reflow occurs during PCI, intracoronary injection of SNP combined verapamil can improve cardiac function, and its safety is good, which is worth extending.
7.Studies of ultrasonic imaging on portal vein thrombosis for patients with portal hypertension splenectomy and analysis of its influencing factors
Xi CHEN ; Zhiyan LI ; Yan WANG ; Yanxian ZHOU ; Yang LIU ; Hui FENG ; Song FENG
Chinese Journal of Medical Ultrasound (Electronic Edition) 2017;14(10):790-793
Objective Through the study of color Doppler ultrasound imaging, to explore the mechanism of portal vein thrombosis for patients with liver cirrhotic portal hypertension splenectomy and its influencing factors. Methods From January 2013 to December 2013, a total of 284 cases of patients with cirrhosis and portal hypertension plenectomy plus pericardial devascularization in 302 Hospital of PLA were reviewed. Color Doppler ultrasound technique was employed to record the thrombosis of portal vein, splenic vein and superior mesenteric vein before and after the surgical procedure. According to the occurrence of portal vein thrombosis after splenectomy, patients were divided into portal vein thrombosis group and non portal vein thrombosis group; the factors that may affect the formation of portal vein thrombus were analyzed by using Logistic regression. Results One hundred and twenty-nine cases of portal vein thrombosis occurred among the 284 patients with splenectomy, the incidence rate was 45.42% (129/284). Logistic regression analysis shows that inner diameters of splenic vein for the group with portal vein thrombosis are significantly different from that of the group without portal vein thrombosis (Z=2.034, P < 0.05), postoperative inner diameter of portal vein (Z=2.037, P<0.05), and prothrombin time (Z=-2.171, P<0.05) are significantly higher in the group with portal vein thrombosis, while preoperative platelet count is significantly lower in the group with portal vein thrombosis (Z=-2.146, P < 0.05); gender, preoperative hepatic artery flow velocity, and blood coagulation time are also the influencing factors of portal vein thrombosis (all P>0.05). Conclusion Color Doppler ultrasound technology can not only monitor, the thrombus formation in portal venous system post splenectomy, it can assess the risk factors of portal vein thrombosis post splenectomy.
8.Therapeutic effect of combined therapy of esmolol hydrochloride and amlodipine on patients with hy-pertension complicated aortic dissection
Yingwen CHEN ; Yanxian WU ; Caihua LI ; You YANG ; Yuying CHEN ; Yiwen ZHANG ; Demou LUO
Chinese Journal of cardiovascular Rehabilitation Medicine 2015;24(3):300-303
Objective:To explore therapeutic effect of esmolol hydrochloride combined amlodipine on patients with hyper-tension complicated aortic dissection (AD) and its influence on patient's blood pressure (BP) and heart rate (HR) .Meth-ods:A total of 110 patients with hypertension complicated AD were randomly and equally divided into amlodipine group and combined treatment group (received amlodipine and esmolol) .Results:Compared with before treatment , after treat-ment 0. 5 ,1. 5 and 7h ,there were significant reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) in both groups ,P<0.01 ,on 7h after treatment ,SBP level of combined treatment group significantly reduced than that of amlodipine group [(101.5 ± 7.8) mmHg vs .(123.4 ± 10.2) mmHg ,P<0.01];on 0.5 ,1.5 and 7h after treatment ,HR and rate pressure product (RPP) of combined treatment group significantly reduced than those of amlodipine group , P<0. 01 all. Compared with amlodipine group after treatment , there were significant rise in standard-reaching rates of BP (56.36% vs .87.27% ) ,HR (38.18% vs .92.73% ) and BP+HR (25.45% vs .81.82% ) in combined treatment group , P<0.01 all. Conclusion:Esmolol combined amlodipine can control blood pressure and heart rate rapidly ,safely and effec-tively in patients with hypertension complicated aortic dissection .

Result Analysis
Print
Save
E-mail