Search results for "lactam"
showing 10 items of 198 documents
Asymmetric Synthesis of Spiro β-Lactamsviaa Squaramide- Catalyzed Sulfa-Michael Addition/Desymmetrization Protocol
2016
An efficient asymmetric synthesis of spirocyclohexenone β-lactams bearing three contiguous stereocenters has been achieved in moderate to good yields and high stereoselectivities. The protocol involves the combination of a squaramide-catalyzed sulfa-Michael addition under desymmetrization via a dynamic kinetic resolution of racemic 2,5-cyclohexadienones.
Ceftolozane-Tazobactam Combination Therapy Compared to Ceftolozane-Tazobactam Monotherapy for the Treatment of Severe Infections: A Systematic Review…
2021
Ceftolozane-tazobactam (C/T) is a combination of an advanced-generation cephalosporin (ceftolozane) with a &beta
Co-existence of virulence factors and antibiotic resistance in new Klebsiella pneumoniae clones emerging in south of Italy
2018
Abstract Background Endemic presence of Klebsiella pneumoniae resistant to carbapenem in Italy has been due principally to the clonal expansion of CC258 isolates; however, recent studies suggest an ongoing epidemiological change in this geographical area. Methods 50 K. pneumoniae strains, 25 carbapenem-resistant (CR-Kp) and 25 susceptible (CS-Kp), collected from march 2014 to march 2016 at the Laboratory of Bacteriology of the Paolo Giaccone Polyclinic University hospital of Palermo, Italy, were characterized for antibiotic susceptibility and fully sequenced by next generation sequencing (NGS) for the in silico analysis of resistome, virulome, multi-locus sequence typing (MLST) and core sin…
Ceftazidime-Avibactam Combination Therapy Compared to Ceftazidime-Avibactam Monotherapy for the Treatment of Severe Infections Due to Carbapenem-Resi…
2020
Ceftazidime-avibactam (CZA) is a novel beta-lactam beta-lactamase inhibitor combination approved for the treatment of complicated urinary tract infections, complicated intra-abdominal infections, and for hospital-acquired/ventilator-associated pneumonia. The aim of this systematic review (PROSPERO registration number: CRD42019128927) was to evaluate the effectiveness of CZA combination therapy versus CZA monotherapy in the treatment of severe infections. The databases included in the search, until February 12th, 2020, were MEDLINE by PubMed, EMBASE, and The Cochrane Central Register of Controlled Trials. We included both randomized controlled trials (RCTs) and non-randomized studies publish…
Extraintestinal pathogenic Escherichia coli sequence type 131 H30-R and H30-Rx subclones in retail chicken meat, Italy
2016
Extraintestinal pathogenic Escherichia coli sequence type 131 (ST131), typically fluoroquinolone-resistant (FQ-R) and/or extended-spectrum β-lactamase (ESBL)-producing, has emerged globally. Among clinical isolates, ST131, primarily its H30-R and H30-Rx subclones, accounts for most antimicrobial-resistant E. coli and is the dominant E. coli strain worldwide. We assessed its prevalence and characteristics among raw chicken meat samples on sale in Palermo, Italy. A collection of 237 fluoroquinolone resistant and ESBL/AmpC producing E. coli isolates, which had been isolated from processed retail chicken meat in the period May 2013-April 2015, was analyzed. Established polymerase chain reaction…
Conjugative ESBL plasmids differ in their potential to rescue susceptible bacteria via horizontal gene transfer in lethal antibiotic concentrations.
2017
Conjugative ESBL plasmids differ in their potential to rescue susceptible bacteria via horizontal gene transfer in lethal antibiotic concentrations
Enhanced Antibacterial Activity of Repurposed Mitomycin C and Imipenem in Combination with the Lytic Phage vB_KpnM-VAC13 against Clinical Isolates of…
2021
Study Group on Mechanisms of Action and Resistance to Antimicrobials (GEMARA) on behalf of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC).
Pharmaceutical Approaches to Target Antibiotic Resistance Mechanisms
2017
There is urgent need for new therapeutic strategies to fight the global threat of antibiotic resistance. The focus of this Perspective is on chemical agents that target the most common mechanisms of antibiotic resistance such as enzymatic inactivation of antibiotics, changes in cell permeability, and induction/activation of efflux pumps. Here we assess the current landscape and challenges in the treatment of antibiotic resistance mechanisms at both bacterial cell and community levels. We also discuss the potential clinical application of chemical inhibitors of antibiotic resistance mechanisms as add-on treatments for serious drug-resistant infections. Enzymatic inhibitors, such as the deriv…
Which non-carbapenem antibiotics are active against extended-spectrum β-lactamase-producing Enterobacteriaceae?
2018
In this study, the activity of 18 non-carbapenem antibiotics was evaluated against 100 extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-Ec) and 50 ESBL-producing Klebsiella pneumoniae (ESBL-Kp) isolated from urinary tract infections and bacteraemia in 2016. Minimum inhibitory concentrations (MICs) were determined using reference methods and the susceptibility profiles were defined according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2017 recommendations. All of the ESBL-Ec isolates were susceptible to ceftazidime/avibactam and a great majority of them were susceptible to fosfomycin (98%), piperacillin/tazobactam (97%), amikacin (97%) and nitr…
Anticancer potential of novel α,β-unsaturated γ-lactam derivatives targeting the PI3K/AKT signaling pathway.
2021
Abstract Six recently synthesized alkyl (Z)-2-(2-oxopyrrolidin-3-ylidene)acetates were evaluated for their potential as cytotoxic and anticancer agents. All compounds were tested in the ERα positive MCF-7, triple negative MDA-MB-231, and Her2+ SKBR-3 breast cancer cell lines. The most lipophilic derivatives, bearing the 4-isopropylphenyl (2) or 4-tert-butylphenyl (3) group at the γ-lactam nitrogen, proved to be cytotoxic against all the cancer cell lines tested (IC50 values ranging from 18 to 63 μM), exerting their greatest activity in SKBR-3 cells, with IC50 values of 33 and 18 μM, respectively. Biological studies showed that the cytotoxic effects of 2 and 3 are accompanied by apoptotic de…