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Objectives: The emergence and expansion of carbapenem-resistant Klebsiella pneumoniae infections is a concern due to the lack of 'first-line' antibiotic treatment options. The ceftazidime/avibactam is an important clinical treatment for carbapenem-resistant K. pneumoniae infections but there is an increasing number of cases of treatment failure and drug resistance. Therefore, a potential solution is combination therapies that result in synergistic activity against K. pneumoniae carbapenemase: producing K. pneumoniae (KPC-Kp) isolates and preventing the emergence of KPC mutants resistant to ceftazidime/avibactam are needed in lieu of novel antibiotics.
Methods: To evaluate their synergistic activity, antibiotic combinations were tested against 26 KPC-Kp strains. Antibiotic resistance profiles, molecular characteristics and virulence genes were investigated by susceptibility testing and whole-genome sequencing. Antibiotic synergy was evaluated by in vitro chequerboard experiments, time-killing curves and dose-response assays. The mouse thigh model was used to confirm antibiotic combination activities in vivo. Additionally, antibiotic combinations were evaluated for their ability to prevent the emergence of ceftazidime/avibactam resistant mutations of blaKPC.
Results: The combination of ceftazidime/avibactam plus meropenem showed remarkable synergistic activity against 26 strains and restored susceptibility to both the partnering antibiotics. The significant therapeutic effect of ceftazidime/avibactam combined with meropenem was also confirmed in the mouse model and bacterial loads in the thigh muscle of the combination groups were significantly reduced. Furthermore, ceftazidime/avibactam plus meropenem showed significant activity in preventing the occurrence of resistance mutations.
Conclusions: Our results indicated that the combination of ceftazidime/avibactam plus meropenem offers viable therapeutic alternatives in treating serious infections due to KPC-Kp.
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http://dx.doi.org/10.1093/jac/dkae074 | DOI Listing |
Langmuir
September 2025
Key Laboratory of Functional Molecular Solids (Ministry of Education), College of Chemistry and Materials Science, Anhui Key Laboratory of Biomedical Materials and Chemical Measurement, Anhui Normal University, Wuhu 241000, China.
The sluggish kinetics and diffusion of lithium polysulfide (LiPS) intermediates lead to the decline in the capacity and rate of high-energy lithium-sulfur (Li-S) batteries. Integrating adsorbents and electrocatalysts into the Li-S system is an effective strategy for suppressing the polysulfide shuttle and enhancing the redox kinetics of sulfur species. The disordered structure of the electrocatalysts exhibits significantly enhanced catalytic activity.
View Article and Find Full Text PDFAdv Mater
September 2025
College of Chemistry, Zhengzhou University, 100 Science Road, Zhengzhou, 450001, P. R. China.
Formic acid (FA) has attracted significant interest as a renewable liquid-phase hydrogen carrier. Hydrogen generation from FA decomposition is essential for the development of hydrogen economy. Designing highly efficient catalysts with different coordination environments for FA dehydrogenation is crucial for fuel-cell applications.
View Article and Find Full Text PDFJ Antimicrob Chemother
September 2025
Department of Pharmaceutical Sciences, University of Michigan College of Pharmacy, Ann Arbor, MI 48109, USA.
Background: Synergy between antibiotic pairs is typically discovered using chequerboard assays that assume uniform, static drug exposure; however, such conditions rarely apply in vivo. Dynamic and heterogeneous tissue environments create spatial and temporal mismatches in drug exposure that can uncouple synergistic interactions, leading to unexpected treatment failure.
Objective: This study aims to develop a physiologically relevant in vitro model that integrates infection-site microenvironments and drug-specific pharmacokinetics.
Transplant Direct
September 2025
Unidad Transplante de О́rganos, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain.
Extracorporeal photopheresis (ECP) is a well-established, safe, and effective immunomodulatory therapy currently used in clinics to decrease T cell-mediated immunity in various disorders, including autoimmune diseases and chronic rejection in organ transplantation. Although the ECP procedure has been shown to induce apoptotic cells that are reintroduced into the patient at the end of the treatment, the precise tolerogenic mechanisms mediated by ECP are not fully understood. Previous in vitro studies have demonstrated that early apoptotic cells express annexins on their cell surface, which suppress myeloid cell activation on stimulation with bacterial lipopolysaccharide through Toll-like receptors.
View Article and Find Full Text PDFFront Oncol
August 2025
Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin, China.
Introduction: Prostate cancer (PC), the most common male genitourinary malignancy and second leading cause of global cancer deaths in men, frequently progresses to lethal castration-resistant PC (CRPC). Ginsenoside Rh2 (GRh2), a ginseng-derived bioactive compound, exhibits antitumor potential, but its efficacy and mechanisms in PC remain unclear.
Methods: PC3 cells were treated with GRh2 to assess proliferation (IC50 calculation), migration, and invasion.