Project description:The spread of carbapenemase-producing Enterobacterales (CPE) is emerging as a significant clinical concern in tertiary hospitals and in particular, long-term care facilities with deficiencies in infection control. This study aims to evaluate an advanced matrix-assisted laser desorption/ionization mass spectrometry (A-MALDI) method for the identification of carbapenemases and further discrimination of their subtypes in clinical isolates. The A-MALDI method was employed to detect CPE target proteins. Enhancements were made to improve detectability and mass accuracy through the optimization of MALDI-TOF settings and internal mass calibration. A total of 581 clinical isolates were analyzed, including 469 CPE isolates (388 KPC, 51 NDM, 40 OXA, and 2 GES) and 112 carbapenemase-negative isolates. Clinical evaluation of the A-MALDI demonstrated 100% accuracy and precision in identifying all the collected CPE isolates. Additionally, A-MALDI successfully discriminated individual carbapenemase subtypes (KPC-2 or KPC-3/4; OXA-48 or OXA-181 or OXA-232; GES-5 or GES-24) and also differentiated co-producing carbapenemase strains (KPC & NDM; KPC & OXA; KPC & GES; NDM & OXA), attributed to its high mass accuracy and simultaneous detection capability. A-MALDI is considered a valuable diagnostic tool for accurately identifying CPE and carbapenemase’s subtypes in clinical isolates. It may also aid in selecting appropriate antibiotics for each carbapenemase subtype. Ultimately, we expect that the A-MALDI method will contribute to preventing the spread of antibiotic resistance and improving human public health.
Project description:The spread of carbapenemase-producing Enterobacterales (CPE) is emerging as a significant clinical concern in tertiary hospitals and in particular, long-term care facilities with deficiencies in infection control. This study aims to evaluate an advanced matrix-assisted laser desorption/ionization mass spectrometry (A-MALDI) method for the identification of carbapenemases and further discrimination of their subtypes in clinical isolates. The A-MALDI method was employed to detect CPE target proteins. Enhancements were made to improve detectability and mass accuracy through the optimization of MALDI-TOF settings and internal mass calibration. A total of 581 clinical isolates were analyzed, including 469 CPE isolates (388 KPC, 51 NDM, 40 OXA, and 2 GES) and 112 carbapenemase-negative isolates. Clinical evaluation of the A-MALDI demonstrated 100% accuracy and precision in identifying all the collected CPE isolates. Additionally, A-MALDI successfully discriminated individual carbapenemase subtypes (KPC-2 or KPC-3/4; OXA-48 or OXA-181 or OXA-232; GES-5 or GES-24) and also differentiated co-producing carbapenemase strains (KPC & NDM; KPC & OXA; KPC & GES; NDM & OXA), attributed to its high mass accuracy and simultaneous detection capability. A-MALDI is considered a valuable diagnostic tool for accurately identifying CPE and carbapenemase’s subtypes in clinical isolates. It may also aid in selecting appropriate antibiotics for each carbapenemase subtype. Ultimately, we expect that the A-MALDI method will contribute to preventing the spread of antibiotic resistance and improving human public health.
Project description:Liver fibrosis is a common pathological process of various chronic liver diseases that can develop into liver cancer. MicroRNAs (miRNAs) are a king of non-coding RNA which are closely related to liver diseases. Thus, this research hope to explore the effect of miR-484 on liver fibrosis and reveal its mechanism. The miRNAs profiles were screened by microRNA sequencing and the location of miR-484 was identified by fluorescence in situ hybridization (FISH) in human liver fibrotic tissues. MiR-484 expression was detected by qRT-PCR in rat primary hepatic stellate cells (HSCs). Bioinformatics analysis and dual-luciferase reporter assay were performed to determine the target gene of miR-484. Liver fibrosis specific signatures were analyzed by qRT-PCR and western blot after miR-484 mimic/inhibitor transfection. The cell apoptosis was detected by Annexin V-FITC/PI double staining. The effect of miR-484 silencing on fibrosis in vivo was investigated in thioacetamide (TAA) induced mice model using the adeno-associated virus carrying miR-484 inhibitor. Enrichment of miR-484 was observed in human liver fibrosis tissues and activated rat primary HSCs. FISH showed that miR-484 was prominently located at fibrotic region and the cytoplasm of HSCs in human liver tissues. Dual-luciferase reporter assay verified that the homeodomain-interacting protein kinases 1 (HIPK1) was the direct target of miR-484. After transfecting miR-484 inhibitor into HSC-T6, HIPK1 were significantly up-regulated, and α-SMA, col1a1, Wnt-3a, Wnt-5a, β-catenin and p-β-catenin were down-regulated, suggesting the restrain effect of miR-484 knockdown on HSCs activation. Conversely, the results were opposite with miR-484 mimic transfection. In addition, the apoptosis of HSC-T6 altered significantly after miR-484 modulation. Moreover, adeno-associated virus carrying miR-484 inhibitor alleviated mice liver fibrosis induced by TAA. In conclusion, miR-484 knockdown ameliorates liver fibrosis by promoting the apoptosis and suppressing HSCs activation via blocking Wnt/β-catenin signaling pathway. MiR-484 and its downstream gene HIPK1 might be selected as novel therapeutic targets of liver fibrosis.
Project description:Resistance to oxaliplatin (OXA) is a complex process affecting the outcomes of metastatic colorectal cancer (CRC) patients treated with this drug. The NF-kBsignalling pathway deregulation has been proposed as an important mechanism involved in this phenomenon. Here, we show that NF-kBwas hyperactivated in in vitro models of OXA-acquired resistance but was attenuated by the addition of Curcumin, a non-toxic NF-kB inhibitor. The concomitant combination of Curcumin+OXA was more effective and synergistic in cell lines with acquired resistance to OXA, leading to the reversion oftheir resistant phenotype, through the inhibition of the NF-kBsignalling cascade. Transcriptomic profiling revealed the up-regulation of three NF-KB-regulated CXC-chemokines, CXCL8, CXCL1 and CXCL2, in the resistant cells thatwere more efficiently down-regulated after OXA+Curcumin treatment as compared to the sensitive cells. Moreover, CXCL8 and CXCL1 gene silencing made resistant cells more sensitive to OXA through the inhibition of the Akt/NF-kBpathway. High expression of CXCL1 in FFPE samples from explant cultures of CRC patients-derived liver metastaseswas associated with response to OXA+Curcumin.In conclusion, we suggest that combination of OXA+Curcumincould be an effective treatment in CRC patients after progression to OXA-based chemotherapy being CXCL1a good candidate predictive marker to this treatment.