Isolation of Hv-CRKP with co-production of three carbapenemases (blaKPC, blaOXA-181 or OXA-232, and blaNDM-1) and a virulence plasmid: a study from a Chinese tertiary hospital.

Background: The worldwide dissemination of K. pneumoniae isolates is a significant public health concern, as these organisms possess a unique capacity to acquire genetic elements encoding both resistance and hypervirulence. This study aims to investigate the epidemiological, resistance, and virulence characteristics of K. pneumoniae isolates that carry both virulence plasmids and blaOXA-48-like genes in a tertiary hospital in China. Methods: A total of 217 clinical isolates of carbapenem-resistant K. pneumoniae (CRKP) were collected between April 2020 and March 2022. The antimicrobial susceptibility test was conducted to evaluate the drug resistance profile. All isolates were screened for the presence of genes encoding carbapenemases (blaKPC, blaNDM, blaIMP, blaVIM, and blaOXA-48-like), ESBLs genes (blaCTX-M, blaSHV, blaTEM), and virulence plasmid pLVPK-borne genes (rmpA, rmpA2, iucA, iroB, and peg344) using polymerase chain reaction (PCR) amplification. Clonal lineages were assigned using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). The plasmid incompatibility groups were identified using PCR-based replicon typing (PBRT). The transferability of carbapenemase-encoding plasmids and pLVPK-like virulence plasmids was assessed via conjugation. The plasmid location of rmpA2 was determined using S1-Pulsed Field Gel Electrophoresis (S1-PFGE) and southern blotting hybridization. The virulence potential of the isolates was assessed using the string test, capsular serotyping, serum killing assay and a Galleria mellonella larval infection model. Results: Of the 217 CRKP clinical isolates collected, 23% were identified as carrying blaOXA-48-like genes. All blaOXA-48-like isolates exhibited resistance to commonly used clinical antimicrobial agents, except for ceftazidime/avibactam, colistin, tigecycline, trimethoprim-sulfamethOXAzole, polymyxin B, and nitrofurantoin. The main common OXA-48-like carbapenemase enzymes were found to be blaOXA-181 and blaOXA-232. MLST and PFGE fingerprinting analysis revealed clonal transmission and plasmid transmission. OXA-48-like producing CRKP isolates mainly clustered in K64 ST11 and K47 ST15. Results of the string Test, serum killing assay (in vitro) and Galleria mellonella infection model (in vivo) indicated hypervirulence. PBRT showed that the blaOXA-181 and blaOXA-232 producing hypervirulent carbapenem-resistant Klebsiella pneumoniae (Hv-CRKP) were mainly carried on ColE-type, IncF, and IncX3. Eight clinical isolates of hv-CRKP were identified as carrying three carbapenem-resistant genes (blaKPC, blaOXA-181 or OXA-232, and blaNDM-1). Moreover, Southern blotting hybridization revealed that all eight isolates had a pLVPK-like virulent plasmid (138.9-216.9 kb) with an uneven number and size of plasmid. Conclusion: In our investigation, we have observed the emergence of hv-CRKP carrying blaOXA-48-like genes, which identified two genetic relationships: clonal transmission and plasmid transmission. PBRT analysis showed that these genes were mainly carried on ColE-type, IncF, and IncX3 plasmids. These isolates have been shown to be hypervirulent in vitro and in vivo. Additionally, eight clinical isolates of hv-CRKP were identified as carrying three carbapenem-resistant genes (blaKPC, blaOXA-181 or OXA-232, and blaNDM-1) and carrying a pLVPK-like virulent plasmid. Hence, our findings highlight the need for further investigation and active surveillance of hypervirulent OXA-48-like producing Hv-CRKP isolates to control their transmission.

Plasma asprosin, CCDC80 and ANGPTL4 levels are associated with metabolic and cardiovascular risk in patients with inflammatory bowel disease.

Asprosin, coiled-coil domain-containing 80(CCDC80) and angiopoietin-like4(ANGPTL4) are newly discovered adipocytokine that affects glucose tolerance, insulin resistance and cardiovascular diseases. The goal of this study was to investigate if a relationship exists among asprosin, CCDC80 and ANGPTL4 and inflammatory bowel disease (IBD). Fifty subjects with newly diagnosed IBD and fifty healthy individuals were enrolled. Patients were treated with standard therapies for 3 months. Plasma asprosin, CCDC80 and ANGPTL4 levels were measured with enzyme-linked immunosorbent assay. High resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia (flow-mediated dilation, FMD) and after sublingual glyceryltrinitrate.Compare with healthy individuals, plasma CCDC80,erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) levels and homeostasis modelassessment of insulin resistance (HOMA-IR) were significantly higher (p < 0.05, respectively), whereas plasma asprosin,ANGPTL4 levels and FMD were significantly lower inboth UC and CD patients(p <0.05). Plasma CCDC80 levels were significantly higher in patients with CD (p<0.05), while plasma asprosin and ANGPTL4 levels were lower (p<0.05) as compared with those in patients with UC. Standard therapies increased plasma asprosin, ANGPTL4 levels and FMD in both UC and CD (p<0.05),UC and CD patientswhile decreased plasma CCDC80, ESR, CRP levels and HOMA-IR (p<0.05). The changes in HOMA-IR and FMD were correlated with the changes in plasma asprosin, CCDC80 and ANGPTL4 levels over the study period (p<0.05). Plasma asprosin, CCDC80 and ANGPTL4 levels may be applied as a significant marker for early stage of insulin resistance and atherosclerosis in IBD, especially of CD.

[The effects of oxidative stress to PCOS].

OBJECTIVE: To investigate the correlation between oxidative stress and PCOS, to provide an evidence for the treatment of PCOS. METHODS: The levels of maternal serum LPO, MDA, SOD, VE and VC were measured in 30 patients with PCOS (PCOS group 1) and in 30 normal women (control group) by chemicalorimetry. After being measured, the patients with PCOS (PCOS group 1) took VE 0.1 qd x 3 months, VC 0.2 bid x 3 months and Diane-35 (Ethinylestradiol and Cyproterone Acetate Tablets) 1 # qd x 21 d/month x 3 months. The LPO, MDA, SOD, VE and VC were measured after three months. The other 30 patients with PCOS (PCOS group 2) were chosen to take Diane-35 (Ethinylestradiol and Cyproterone Acetate Tablets) 1 qd x 21 d/month x 3 months only. The menstrual cycles were viewed in PCOS group 1 and PCOS group 2 for three months. RESULTS: The levels of maternal serum LPO and MDA in patients with PCOS (PCOS group 1) were significant higher than that in normal women (control group) (P < 0.05). The levels of maternal serum VE, VC and SOD in patients with PCOS (PCOS group 1) were lower than that in normal women (control group) (P < 0.05). The levels of LPO and MDA after taking Diane-35, VE and VC were lower than that before taking Diane-35, VE and VC. The levels of VE, VC and SOD after taking Diane-35, VE and VC were higher than that before taking Diane-35, VE and VC. The recoveries of menstrual cycles in PCOS group 1 were better than that in PCOS group 2. CONCLUSION: The PCOS may be related to oxidative stress (the metabolism imbalance of reactive oxygen species). The antioxidants may improve the prognosis of PCOS.