J Clin Endocrinol Metab
August 2022
Context: Childhood obesity disproportionately affects Hispanic youth. The skeletal system appears to be a target organ of the adverse effects of obesity. Yet, the relationship between adiposity and bone health in youth and the modulating factors are not well understood.
View Article and Find Full Text PDFThe FDA-CDC Antimicrobial Resistance Isolate Bank was created in July 2015 as a publicly available resource to combat antimicrobial resistance. It is a curated repository of bacterial isolates with an assortment of clinically important resistance mechanisms that have been phenotypically and genotypically characterized. In the first 2 years of operation, the bank offered 14 panels comprising 496 unique isolates and had filled 486 orders from 394 institutions throughout the United States.
View Article and Find Full Text PDFTher Clin Risk Manag
February 2009
Retapamulin is a novel semisynthetic pleuromutilin antibiotic specifically designed for use as a topical agent. The unique mode of action by which retapamulin selectively inhibits bacterial protein synthesis differentiates it from other nonpleuromutilin antibacterial agents that target the ribosome or ribosomal factors, minimizing the potential for target-specific cross-resistance with other antibacterial classes in current use. In vitro studies show that retapamulin has high potency against the Gram-positive bacteria (Staphylococcus aureus, Streptococcus pyogenes, and coagulase-negative staphylococci) commonly found in skin and skin-structure infections (SSSIs), including S.
View Article and Find Full Text PDFExpert Rev Anti Infect Ther
April 2009
Retapamulin is a new topical pleuromutilin antibiotic for the treatment of skin and skin-structure infections, including impetigo. In vitro studies indicate that retapamulin has a unique mode of action that minimizes the potential for target-specific cross-resistance with other antibacterials and a limited potential for resistance development. Its spectrum of activity includes the most likely causative pathogens Staphylococcus aureus and Streptococcus pyogenes.
View Article and Find Full Text PDFRetapamulin MICs of > or =2 microg/ml were noted for 6 of 5,676 S. aureus recent clinical isolates evaluated. The ABC proteins VgaAv and VgaA were found to be responsible for the reduced susceptibility to pleuromutilins exhibited by these six isolates.
View Article and Find Full Text PDFDetermining the genetic characteristics of Staphylococcus aureus is important for better understanding of the global and dynamic epidemiology of this organism as we witness the emergence and spread of virulent and antibiotic-resistant clones. We genotyped 292 S. aureus isolates (105 methicillin resistant and 187 methicillin susceptible) using a combination of pulsed-field gel electrophoresis, multilocus sequence typing, and SCCmec typing.
View Article and Find Full Text PDFBackground: The majority of recent community-associated methicillin-resistant Staphylococcus aureus (MRSA) infections in the United States have been caused by a single clone, USA300. USA300 secretes Panton-Valentine leukocidin (PVL) toxin, which is associated with highly virulent infections.
Methods: We sequenced the PVL genes of 174 S.
Background: Retapamulin is a novel pleuromutilin antibacterial developed for topical use.
Objective: To compare the efficacy and safety of retapamulin ointment, 1% (twice daily for 5 days), with sodium fusidate ointment, 2% (3 times daily for 7 days), in impetigo.
Methods: A randomized (2:1 retapamulin to sodium fusidate), observer-blinded, noninferiority, phase III study in 519 adult and pediatric (aged > or = 9 months) subjects.
J Am Acad Dermatol
December 2006
Background: New antibacterial agents with activity against pathogenic strains resistant to established antibiotics are needed to treat patients with secondarily infected dermatitis (SID).
Objective: We sought to determine the clinical safety and efficacy of topical retapamulin ointment 1% versus oral cephalexin for the treatment of SID.
Methods: Patients with SID were randomly assigned to retapamulin ointment 1% (twice daily [bid]) for 5 days, or oral cephalexin (500 mg bid) for 10 days.
Introduction: Retapamulin is a novel, topical antibacterial of the pleuromutilin class in development for the treatment of secondarily infected traumatic lesions of the skin.
Methods: The efficacy, safety, and tolerability of topical retapamulin ointment, 1% for 5 days twice daily was evaluated in 2 identical, randomized, double-blind, double-dummy, multicenter studies vs oral cephalexin, 500 mg twice daily for 10 days, in 1904 patients with secondarily infected traumatic lesions.
Results: Clinical success rates were 89.
Bioorg Med Chem Lett
September 2006
Synthesis of C(12) des-methyl ketolide is developed featuring an intramolecular epoxide formation/elimination process to establish the C(12) stereocenter. These ketolides are potent against several key respiratory pathogens, including erythromycin resistant erm- and mef-containing strains of Streptococcus pneumoniae.
View Article and Find Full Text PDFA novel series of C(12) ethyl erythromycin derivatives have been discovered which exhibit in vitro and in vivo potency against key respiratory pathogens, including those resistant to erythromycin. The C(12) modification involves replacing the natural C(12) methyl group in the erythromycin core with an ethyl group via chemical synthesis. From the C(12) ethyl macrolide core, a series of C(12) ethyl ketolides were prepared and tested for antibacterial activity against a panel of relevant clinical isolates.
View Article and Find Full Text PDFA novel series of C12 vinyl erythromycin derivatives have been discovered which exhibit in vitro and in vivo potency against key respiratory pathogens. The C12 modification involves replacing the natural C12 methyl group in the erythromycin core with a vinyl group via chemical synthesis. From the C12 vinyl macrolide core, a series of C12 vinyl ketolides was prepared.
View Article and Find Full Text PDFA fluoroquinolone prodrug, PA2808, was prepared and shown to convert to the highly active parent drug PA2789. In vitro and in vivo activation of PA2808 by alkaline phosphatase was demonstrated using disk diffusion and rat lung infection models. The water solubility of PA2808 showed a marked increase compared to PA2789 over a pH range suitable for aerosol drug delivery.
View Article and Find Full Text PDFBioorg Med Chem
January 2000
As a strategy to increase the penetration of antibiotic drugs through the outer membrane of gram-negative pathogens, facilitated transport through siderophore receptors has been frequently exploited. Hydroxamic acids, catechols, or very close isosteres of catechols, which are mimics of naturally occurring siderophores, have been used successfully as covalently linked escorting moieties, but a much wider diversity of iron binding motifs exists. This observation, coupled to the relative lack of specificity of siderophore receptors, prompted us to initiate a program to identify novel, noncatechol siderophoric structures.
View Article and Find Full Text PDFAminoglycoside-resistance mechanisms were characterized in Pseudomonas aeruginosa isolates from cystic fibrosis (CF) patients during a recent clinical trial of inhaled tobramycin. Impermeability, in which bacteria have reduced susceptibility to all aminoglycosides, was the predominant mode of resistance in isolates obtained both before and after 6 months of cyclic treatment with tobramycin or placebo administered by aerosol. Enzymatic resistance mechanisms were found in fewer than 10% of resistant isolates.
View Article and Find Full Text PDFAntimicrob Agents Chemother
December 1999
Pseudomonas aeruginosa can employ many distinct mechanisms of resistance to aminoglycoside antibiotics; however, in cystic fibrosis patients, more than 90% of aminoglycoside-resistant P. aeruginosa isolates are of the impermeability phenotype. The precise molecular mechanisms that produce aminoglycoside impermeability-type resistance are yet to be elucidated.
View Article and Find Full Text PDFAntimicrob Agents Chemother
December 1999
The in vitro activity of tobramycin was compared with those of six other antimicrobial agents against 1,240 Pseudomonas aeruginosa isolates collected from 508 patients with cystic fibrosis during pretreatment visits as part of the phase III clinical trials of tobramycin solution for inhalation. The tobramycin MIC at which 50% of isolates are inhibited (MIC(50)) and MIC(90) were 1 and 8 microg/ml, respectively. Tobramycin was the most active drug tested and also showed good activity against isolates resistant to multiple antibiotics.
View Article and Find Full Text PDFA series of pure fluoroquinolone antiinfective agents was prepared by multiple parallel synthesis using a simple new apparatus. These compounds were evaluated biologically against Gram-positive and Gram-negative microorganisms and against a BCG strain transfected with luciferase in a fluorescence-based antitubercular assay. Activity against relatively fast growing, acid-fast Mycobacterium smegmatis was determined in part by agar-dilution streak assays.
View Article and Find Full Text PDFPseudomonas aeruginosa endobronchial infection causes significant morbidity and mortality among cystic fibrosis patients. Microbiology results from two multicenter, double-blind, placebo-controlled trials of inhaled tobramycin in cystic fibrosis were monitored for longitudinal changes in sputum microbial flora, antibiotic susceptibility, and selection of P. aeruginosa isolates with decreased tobramycin susceptibility.
View Article and Find Full Text PDFBerberine (4) is responsible for the activity of an extract of a commercial root sample of Hydrastis canadensis against multiply drug resistant Mycobacterium tuberculosis. Two new quinic acid feruloyl esters, compounds 2 and 3, have been isolated from the same source along with canadine (1c), 8-oxotetrahydrothalifendine (1), and beta-hydrastine (5). These were found to be inactive.
View Article and Find Full Text PDF