Objective:To investigate relationship between AdeABC efflux pump and resistance of Acinetobacter baumannii against carbapenem.Methods:Carbapenem-resistant strains were acquired from multistep selection resistance test by meropenem in vitro.The quantitation test for sensitivities of strains before and after induction was determined by the E-test,and carbonylcyanide-m-chlorophenylhydrazone (CCCP) inhibition test was used to screen efflux pump.PCR,sequencing analysis,or real-time PCR was used to analyze the changes of regulatory genes adeR and adeS of the AdeABC efflux pump system,or expressions of adeA,adeB,adeR,and adeS in the strains before and after induction,respectively.Results:The minimal inhibitory concentrations (MICs) of meropenem were at 0.38 μg/mL and 0.25 μg/mL in parental sensitive strain S25595 and S7257,respectively,and the MICs of meropenem for both S25595 and S7257 after induction were more than 32 μg/mL.Compared with parental sensitive strains,the expression level of adeA,adeB,adeR,and adeS mRNA were elevated from 2.45 to 9.44 times,but there were no gene mutations or insertion sequences in the regulatory gene adeS and adeR.Conclusion:High expression of the AdeABC efflux pump system in Acinetobacter baumannii is closely associated with meropenem resistance,The upregulation of adeA and adeB expression is not due to gene mutations in the regulatory gene adeS and adeR and other mechanisms might account for it.

OBJECTIVE: To explore the correlation between peripheral blood cytomegalovirus (CMV) DNA level and cyclosporine A (CsA) plasma concentration among allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients who received immunosuppressant treatment, and to evaluate the potential clinical value. METHODS: A total of 32 allo-HSCT patients were enrolled and their data were analyzed retrospectively. Ganciclovir was used to prevent CMV infection before the transplantation. Routine fluorescence PCR was admitted to test the blood CMV DNA level. The patients were divided into 2 groups: a CMV DNA positive group and a CMV DNA negative group. Enzyme multiplied immunoassay technique was adopted regularly to monitor the blood CsA concentration. The correlation between CMV DNA level and CsA concentration was analyzed. RESULTS: The CMV infection rate in patients who received allo-HSCT was 53.13%. The blood CsA concentration in the CMV DNA positive group was significantly higher than that in the CMV DNA negative group (P<0.05). Through the ROC curve, the area under the curve on Day 1, 7, and 14 had statistical significance compared with 0.5, and the corresponding blood CsA concentration was 203.15, 215.55, and 302.65 ng/mL, respectively. CONCLUSION Immunosuppressive drug concentration can affect the dynamic changes of CMV DNA. High blood CsA concentration may be one of the reasons for CMV infection. Monitoring the blood CsA concentration may provide guidance for clinical treatment.
Adolescent ; Adult ; Cyclosporine ; adverse effects ; blood ; therapeutic use ; Cytomegalovirus ; isolation & purification ; Cytomegalovirus Infections ; prevention & control ; DNA, Viral ; blood ; Female ; Ganciclovir ; therapeutic use ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Humans ; Immunosuppressive Agents ; adverse effects ; blood ; therapeutic use ; Leukemia ; therapy ; Male ; Retrospective Studies ; Young Adult

Objective:In recent years,the prevalence of diabetic nephropathy(DN)has increased significantly.An increasing number of studies have shown that lymphocyte-associated inflammatory responses play a role in DN.This study aims to investigate the relationship between lymphocytes and DN in patients with autoimmune diabetes. Methods:The clinical data of 226 patients with Type 1 diabetes(T1D)and 79 patients with latent autoimmune diabetes in adults(LADA)were retrospectively studied and stratified according to the urinary albumin to creatinine ratio(ACR).Risk factors associated with DN were analyzed using correlation analysis and logistic regression. Results:In T1D and LADA patients,systolic blood pressure(SBP),uric acid duration,and diabetes duration in patients with normoalbuminuria were lower or shorter than those in patients with macroalbuminuria(P＜0.05).The lymphocyte count of T1D patients was significantly higher than that in LADA patients(P＜0.05),while the neutrophil to lymphocyte ratio(NLR)of T1D patients was significantly lower than that in LADA patients(P＜0.05).The lymphocyte count in the T1D patients with normoalbuminuria was lower than that those with macroalbuminuria(P＜0.05).The NLR was lower in the T1D patients with macroalbuminuria than those with microalbuminuria and normoproteinuria(all P＜0.01).Based on logistic regression analysis,lymphocytes were independently associated with DN in T1D after adjusting for various known risk factors such as course of disease,age,gender,dyslipidemia,hypertension,and smoking status.Analysis of the receiver operating characteristic curve of subjects predicting lymphocytes in normoalbuminuria showed that the area under the curve was 0.601(95% CI 0.510 to 0.693,P=0.039),and when the cutoff value of lymphocytes was 2.332,the sensitivity was 37.0%,and the specificity was 82.5%. Conclusion:Lymphocyte counts in autoimmune diabetic patients are closely associated with DN,suggesting that lymphocyte-mediated inflammation may be involved in the pathogenesis of DN in autoimmune diabetic patients.This study provides a possible perspective for using lymphocytes as a potential biomarker for the early identification of individuals at risk for DN and potential therapeutic targets for DN.

OBJECTIVES: The prevalence of carbapenem-resistant Enterobacterales (CRE) presents a significant challenge in clinical anti-infective treatment. This study aims to investigate drug resistance and the molecular epidemiological characteristics of CRE in our area. Additionally, we seek to evaluate practicality of utilizing carbapenemase inhibitor enhancement test in clinical laboratory. METHODS: Non-repeated CREs isolated from clinical specimens at Xiangya Hospital, Central South University, were collected. Minimum inhibitory concentration (MIC) combined with Kirby-Bauer (KB) assay was used to detect the drug susceptibility of the strains, and 13 carbapenemase-producing genes were detected by PCR. The phenotype of 126 strains of carbapenemase-producing Enterobacterales identified by PCR was detected by the carbapenemase inhibitor enhancement test to understand the agreement between the method and the gold standard PCR results. RESULTS: Among 704 CRE strains examined, we observed significant drug resistance in 501 strains dentified as carbapenemase-producing Enterobacterales (CPE). Klebsiella pneumoniae was the predominant CPE strain, followed by Enterobacter cloacae and Escherichia coli. A total of 9 carbapenemase types were detected, including Klebsiella pneumoniae carbapenemase (KPC), New Delhi metallo-β-lactamase (NDM), Verona integron- encoded metallo-β-lactamases (VIM), imipenemase (IMP), oxacillinase-48 (OXA-48), and rare imipenem-hydrolyzing β-lactamase (IMI), adelaide imipenemase (AIM), Bicêtre carbapenemase (BIC), and guiana extended-spectrum β-lactamase (GES). The detection rate of KPC serine carbapenemase was 61.7% (309/501). The carbapenemase inhibitor enhancement test exhibited a 100% consistency rate for the strains producing Class A serine carbapenemase and/or Class B metallo-β-lactamases. CONCLUSIONS CRE strains in Changsha, Hunan, China, are wide distribution and exhibit carbapenemase production. The main mechanism of carbapenem resistance in these bacterias is predominatly attributed to the production of KPC serine carbapenemase. The presence of GES and IMI genes carried by Enterobacterales has been detected for the first time in this region. The carbapenemase inhibitor enhancement test has been proven to be an accurate method for detecting CRE producing Class A serine carbapenemase and/or Class B metallo-β-lactamases. This method offers simpicity of operation and ease of results interpretation, making it weel-suited meeting the clinical microbiology laboratory's reguirements for the detection of serine carbapenemase and metallo-β-lactamases.
Humans ; Carbapenems/pharmacology* ; Molecular Epidemiology ; Bacterial Proteins/analysis* ; beta-Lactamases/analysis* ; Klebsiella pneumoniae/genetics* ; Escherichia coli ; Microbial Sensitivity Tests ; Serine ; Anti-Bacterial Agents/pharmacology*