Publications by authors named "Karen Amsler"

The global burden of disease caused by extraintestinal pathogenic (ExPEC) is increasing as the prevalence of multidrug-resistant strains rises. A multivalent ExPEC O-antigen bioconjugate vaccine could have a substantial impact in preventing bacteremia and urinary tract infections. Development of an ExPEC vaccine requires a readout to assess the functionality of antibodies.

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The aim of this study was to evaluate the in vitro efficacy of ceftobiprole and comparator antibiotics, either alone or in combination, in staphylococcal MBEC™ (minimum biofilm eradication concentration) and colony biofilm assays at dilutions of the maximum free-drug plasma concentration attained during clinical use (fCmax). Staphylococci tested included meticillin-susceptible and meticillin-resistant Staphylococcus aureus (n=6) and Staphylococcus epidermidis (n=2). Relative to no-drug controls, after 7 days of exposure ceftobiprole concentrations from 1/4 fCmax to fCmax generally decreased CFUs in MBEC or colony biofilms of S.

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Article Synopsis
  • The study compared the effectiveness of ceftobiprole medocaril, vancomycin, daptomycin, and their combinations in treating infective endocarditis caused by MRSA and GISA in rats.
  • Ceftobiprole medocaril showed the best results as a standalone treatment, significantly reducing bacterial counts in the infected heart and achieving higher rates of sterile vegetation than other treatments.
  • Synergistic effects were observed when ceftobiprole was combined with vancomycin, suggesting that this combination therapy could be beneficial for treating these difficult-to-treat infections, indicating the need for further research.
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  • Community-acquired pneumonia (CAP) can lead to hospitalization in 20% of cases, and ceftobiprole is a new antibiotic that targets major bacteria responsible for CAP, including resistant strains like MRSA.
  • A study involving 706 hospitalized CAP patients compared ceftobiprole against an expert-recommended treatment (ceftriaxone ± linezolid) and found similar cure rates, with 76.4% for ceftobiprole and 79.3% for the comparator.
  • Both treatments were well tolerated, but ceftobiprole had a slightly higher incidence of mild side effects like nausea and vomiting, yet it demonstrated non-inferiority, suggesting it could be a good option for treating
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Background: Antibiotic resistance is problematic in Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumannii, and is often associated with serious infections. Carbapenems are often one of the few remaining therapeutic options, so it is important to monitor carbapenem activity against these pathogens and to identify resistance mechanisms.

Methods: Carbapenem susceptibilities were determined for 14 359 Enterobacteriaceae, 3614 P.

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JNJ-Q2, a novel fluorinated 4-quinolone, was evaluated for its antibacterial potency by broth and agar microdilution MIC methods in studies focused on skin and respiratory tract pathogens, including strains exhibiting contemporary fluoroquinolone resistance phenotypes. Against a set of 118 recent clinical isolates of Streptococcus pneumoniae, including fluoroquinolone-resistant variants bearing multiple DNA topoisomerase target mutations, an MIC(90) value for JNJ-Q2 of 0.12 microg/ml was determined, indicating that it was 32-fold more potent than moxifloxacin.

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Meticillin-resistant Staphylococcus aureus (MRSA) isolates from two worldwide ceftobiprole Phase 3 clinical trials for the treatment of complicated skin and skin-structure infections were characterised by clonality, staphylococcal cassette chromosome mec (SCCmec) type and the presence of Panton-Valentine leukocidin (PVL). PVL was predominantly found in US isolates (196/231 vs. 13/110 non-US isolates).

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Twenty-six institutions in New England and 24 institutions in West South Central regions participating in the Tracking Resistance in the United States Today (TRUST) 4-9 surveillance studies (2000-2005) were monitored for levofloxacin-resistant Streptococcus pneumoniae to determine if resistance was sporadic or persistent. Levofloxacin was used as a representative of the respiratory fluoroquinolones. Levofloxacin-resistant isolates were identified in 8 of the 26 New England institutions and in 11 of the 24 West South Central institutions during the surveillance period.

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In phase 3 clinical trials for ceftobiprole treatment of complicated skin and skin structure infections, 1,219 gram-positive and 276 gram-negative aerobic baseline pathogens were identified. Ceftobiprole inhibited all staphylococcal isolates, including methicillin-resistant strains, at MICs of View Article and Find Full Text PDF

Article Synopsis
  • Ceftobiprole is a new cephalosporin antibiotic being tested against MRSA and was compared to vancomycin in a clinical trial for complicated skin infections.
  • The trial involved 784 patients, showing similar cure rates for both drugs (93.3% for ceftobiprole vs 93.5% for vancomycin) with effective results for MRSA cases specifically.
  • Adverse events were reported by around 52% of patients on ceftobiprole and 51% on vancomycin, with nausea and taste disturbance being the most common, but overall, ceftobiprole was deemed effective and well-tolerated.
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The identification of several potent pyrazole-based inhibitors of bacterial dihydroorotate dehydrogenase (DHODase) via a directed parallel synthetic approach is described below. The initial pyrazole-containing lead compounds were optimized for potency against Helicobacter pylori DHODase. Using three successive focused libraries, inhibitors were rapidly identified with the following characteristics: K(i) < 10 nM against H.

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We evaluated the effect of optimized doses and dosing schedules of metronidazole, tetracycline, and bismuth-metronidazole-tetracycline (BMT) triple therapy with only 1 day of dosing on Helicobacter pylori SS1 titers in a mouse model. A reduction of bacterial titers was observable with 22.5 and 112.

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