220 research outputs found

    Transferable plasmid mediating resistance to multiple antimicrobial agents in Klebsiella pneumoniae isolates in Greece

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    AbstractObjective To investigate the underlying resistance mechanisms in 10 Klebsiella pneumoniae isolates.Methods Ten K. pneumoniae strains according to distinct bacteriocin typing and REP-PCR, were examined for their plasmid content, their ability to transfer their resistance to aminoglycosides and third-generation cephalosporins, and their production of aminoglycoside-modifying enzymes and β-lactamases.Results Transfer of resistance to the above-mentioned antibiotics as well as to co-trimoxazole and tetracycline in Escherichia coli strain RC 85 at a frequency of 5–106 was achieved for all strains by conjugation. Similar strains harbor a self-transferable multiresistant plasmid (80 kb) with similar EcoRI and HindIII restriction patterns. This plasmid encodes an extended-spectrum β-lactamase which confers high-level resistance to third-generation cephalosporins and aztreonam. It produces SHV-5 β-lactamase, as demonstrated by isoelectric focusing and DNA sequencing. Aminoglycoside resistance was co-transferred, and AAC(6′)-I, mediating resistance to gentamicin, tobramycin, netilmicin and amikacin, and AAC(3)-I, mediating resistance to gentamicin and sisomycin, were encoded in all isolates and their transconjugants, while APH(3′)-I, mediating resistance to kanamycin and neomycin, was encoded in seven strains.Conclusions It appears that a multiresistant transferable plasmid encoding the SHV-5 β-lactamase, causing unusually high resistance to ceftazidime and aztreonam, and the combination AAC(6′)-I + AAC(3)-I of acetylating enzymes causing, also resistance to all clinically available aminoglycosides, is established in K. pneumoniae in Greece

    Χρώμα και ηχόχρωμα στη μουσική του 20ου αιώνα

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    Η συγκεκριμένη εργασία μελετάει τον τρόπο με τον οποίο μπορεί το χρώμα να υπάρξει μέρος μιας σύνθεσης του 20ου αιώνα, καθώς και πόσο σημαντικό ρόλο παίζει η χρήση του ηχοχρώματος εκείνη την περίοδο. Οι συνθέτες του 20ου αιώνα έχουν την επιλογή να συμπεριλάβουν το χρώμα στις συνθέσεις τους άμεσα ή έμμεσα. Αυτή η σύνδεση χρώματος και ήχου μπορεί να γίνει βάσει των αισθητικών ή φιλοσοφικών κριτηρίων του συνθέτη, ή έχοντας για οδηγό τη συναισθησία˙ ένα νευροψυχολογικό χαρακτηριστικό το οποίο συνδέει μεταξύ άλλων το χρώμα με τον ήχο. Οι συνθέτες που έχουν συναισθησία, όπως ο Alexander Scriabin και ο Olivier Messiaen που μελετώνται στη συγκεκριμένη εργασία, έχουν την επιλογή να αξιοποιήσουν αυτό τους το χαρακτηριστικό στις συνθέσεις τους.This particular thesis studies how color can be part of a composition in the 20th century, as well as how important is the use of timbre in that period. 20th century composers have the option of including color in their compositions directly or indirectly. This connection of color and sound can be made based on the composer's aesthetic or philosophical criteria, or guided by synesthesia; a neuropsychological characteristic that connects color and sound, among other things. Composers who have synesthesia, such as Alexander Scriabin and Olivier Messiaen that are studied in this paper, have the option to include this characteristic in their compositions

    Scaling relations for implantation of size-selected Au, Ag, and Si clusters into graphite

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    The deposition of size-selected clusters represents a new route to the fabrication of truly nanometer-scale surface architectures, e.g., nanopores. We report a systematic experimental study, coupled with molecular dynamics simulations, of the implantation depths of size-selected Au7, Ag7, and Si7 clusters in the model graphite substrate. For impact energies between 1.0 and 5.5 keV, we find that the implantation depth scales linearly with the momentum of the clusters for all three types of cluster. This “universal” behavior is consistent with a (viscous) retarding force proportional to the velocity of the cluster, akin to Stokes’s law

    Skeletal muscle NOX4 is required for adaptive responses that prevent insulin resistance

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    Reactive oxygen species (ROS) generated during exercise are considered integral for the health-promoting effects of exercise. However, the precise mechanisms by which exercise and ROS promote metabolic health remain unclear. Here, we demonstrate that skeletal muscle NADPH oxidase 4 (NOX4), which is induced after exercise, facilitates ROS-mediated adaptive responses that promote muscle function, maintain redox balance, and prevent the development of insulin resistance. Conversely, reductions in skeletal muscle NOX4 in aging and obesity contribute to the development of insulin resistance. NOX4 deletion in skeletal muscle compromised exercise capacity and antioxidant defense and promoted oxidative stress and insulin resistance in aging and obesity. The abrogated adaptive mechanisms, oxidative stress, and insulin resistance could be corrected by deleting the H2O2-detoxifying enzyme GPX-1 or by treating mice with an agonist of NFE2L2, the master regulator of antioxidant defense. These findings causally link NOX4-derived ROS in skeletal muscle with adaptive responses that promote muscle function and insulin sensitivity

    Metabolomic analysis of insulin resistance across different mouse strains and diets

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    Insulin resistance is a major risk factor for many diseases. However, its underlying mechanism remains unclear in part because it is triggered by a complex relationship between multiple factors, including genes and the environment. Here, we used metabolomics combined with computational methods to identify factors that classified insulin resistance across individual mice derived from three different mouse strains fed two different diets. Three inbred ILSXISS strains were fed high-fat or chow diets and subjected to metabolic phenotyping and metabolomics analysis of skeletal muscle. There was significant metabolic heterogeneity between strains, diets, and individual animals. Distinct metabolites were changed with insulin resistance, diet, and between strains. Computational analysis revealed 113 metabolites that were correlated with metabolic phenotypes. Using these 113 metabolites, combined with machine learning to segregate mice based on insulin sensitivity, we identified C22:1-CoA, C2-carnitine, and C16-ceramide as the best classifiers. Strikingly, when these three metabolites were combined into one signature, they classified mice based on insulin sensitivity more accurately than each metabolite on its own or other published metabolic signatures. Furthermore, C22:1-CoA was 2.3-fold higher in insulin-resistant mice and correlated significantly with insulin resistance. We have identified a metabolomic signature composed of three functionally unrelated metabolites that accurately predicts whole-body insulin sensitivity across three mouse strains. These data indicate the power of simultaneous analysis of individual, genetic, and environmental variance in mice for identifying novel factors that accurately predict metabolic phenotypes like whole-body insulin sensitivity

    Transition metals on the (0001) surface of graphite: Fundamental aspects of adsorption, diffusion, and morphology

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    In this article, we review basic information about the interaction of transition metal atoms with the (0001) surface of graphite, especially fundamental phenomena related to growth. Those phenomena involve adatom-surface bonding, diffusion, morphology of metal clusters, interactions with steps and sputter-induced defects, condensation, and desorption. General traits emerge which have not been summarized previously. Some of these features are rather surprising when compared with metal-on-metal adsorption and growth. Opportunities for future work are pointed out

    Year in review in Intensive Care Medicine, 2008: II. Experimental, acute respiratory failure and ARDS, mechanical ventilation and endotracheal intubation

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    SCOPUS: re.jinfo:eu-repo/semantics/publishe
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