244 research outputs found
Limited Multidrug Resistance Efflux Pump Overexpression among Multidrug-Resistant Escherichia coli Strains of ST131
Gram-negative bacteria partly rely on efflux pumps to facilitate growth under stressful conditions and to increase resistance to a wide variety of commonly used drugs. In recent years E. coli ST131 has emerged as a major cause of extraintestinal infection frequently exhibiting an MDR phenotype. The contribution of efflux to MDR in emerging E. coli MDR clones however, is not well studied. We characterized strains from an international collection of clinical MDR-E. coli isolates by MIC testing with and without the addition of the AcrAB-TolC efflux inhibitor 1-(1-naphthylmethyl)-piperazine (NMP). MIC data for 6 antimicrobial agents and their reversion by NMP were analyzed by Principal Component Analysis (PCA). PCA revealed a group of 17/34 MDR-E. coli exhibiting increased susceptibility to treatment with NMP suggesting an enhanced contribution of efflux pumps to antimicrobial resistance in these strains (termed "enhanced efflux phenotype" [EEP]). Only 1/17 EEP strains versus 12/17 non-EEP MDR strains belonged to the ST131 clonal group. Whole-genome sequencing revealed marked differences in efflux-related genes between EEP and control strains, with the majority of notable amino-acid substitutions occurring in AcrR, MarR and SoxR. qRT-PCR of multiple efflux-related genes showed significant overexpression of the AcrAB-TolC-system in EEP strains, whereas in the remaining strains we found enhanced expression of alternative efflux proteins. We conclude that a proportion of MDR E. coli exhibit an EEP, which is linked to an overexpression of the AcrAB-TolC-efflux-pump and a distinct array of genomic variations. Members of ST131, although highly successful, are less likely to exhibit the EEP
Vocal Culture in the Age of Laryngoscopy
For several months beginning in 1884, readers of Life, Science, Health, the Atlantic Monthly and similar magazines would have encountered half-page advertisements for a newly patented medical device called the âammoniaphoneâ (Figure 2.1). Invented and promoted by a Scottish doctor named Carter Moffat and endorsed by the soprano Adelina Patti, British Prime Minister William Gladstone and the Princess of Wales, the ammoniaphone promised a miraculous transformation in the voices of its users. It was recommended for âvocalists, clergymen, public speakers, parliamentary men, readers, reciters, lecturers, leaders of psalmody, schoolmasters, amateurs, church choirs, barristers, and all persons who have to use their voices professionally, or who desire to greatly improve their speaking or singing tonesâ. Some estimates indicated that Moffat sold upwards of 30,000 units, yet the ammoniaphone was a flash in the pan as far as such things go, fading from public view after 1886
Opera and Hypnosis: Victor Maurelâs Experiments with Verdiâs Otello
One day in his private home on the avenue Bugeaud, in Parisâs sixteenth arrondissement, the famous baritone Victor Maurel hosted a meeting which combined music with hypnotism of a young woman
Science, Technology and Love in Late Eighteenth-Century Opera
It is a tale told by countless operas: young love, thwarted by an old manâs financially motivated marriage plans, triumphs in the end thanks to a deception that tricks the old man into blessing the young loversâ union. Always a doddering fool, the old man is often also an enthusiast for knowledge. Such is the case, for instance, in Carlo Goldoniâs comic opera libretto Il mondo della luna (1750), in which Buonafedeâs interest in the moon opens him to an elaborate hoax that has him believe he and his daughters have left Earth for the lunar world; and also in the Singspiel Die LuftbĂ€lle, oder der Liebhaber Ă la Montgolfier (1788), wherein the apothecary Wurm trades Sophie, the ward he intended to marry himself, for a technological innovation that will make him a pioneering aeronaut
Unsound Seeds
With this image of a curtain hiding and at the same time heightening some terrible secret, Max Kalbeck began his review of the first Viennese performance of Richard Straussâs Salome. Theodor W. Adorno picked up the image of the curtain in the context of Straussâs fabled skill at composing non-musical events, when he identified the opening flourish of Straussâs Salome as the swooshing sound of the rising curtain. If this is so, the succĂšs de scandale of the opera was achieved, in more than one sense, as soon as the curtain rose at Dresdenâs Semperoper on 10 December 1905.
Critics of the premiere noted that the opera set âboundless wildness and degeneration to musicâ; it brought âhigh decadenceâ onto the operatic stage; a âcomposition of hysteriaâ, reflecting the âdisease of our timeâ, Salome is âhardly music any moreâ.The outrage did not end there
Operatic Fantasies in Early Nineteenth-Century Psychiatry
In his celebrated essay on insanity in the Dictionnaire des sciences mĂ©dicales (1816), French psychiatrist Ătienne Esquirol marvelled at the earlier custom of allowing asylum inmates to attend theatrical productions at Charenton
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