910 research outputs found

    Complete Genome Sequence of A388, an Antibiotic-Resistant Acinetobacter baumannii Global Clone 1 Isolate from Greece

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    Copyright © 2019 Hamidian et al. Acinetobacter baumannii isolate A388, recovered in Greece in 2002, represents a distinct antibiotic-resistant lineage of global clone 1 (GC1) producing the OXA-58 carbapenemase. We present the complete 4.332-Mbp genome sequence (chromosome plus 1 plasmid), generated by combining long (MinION) and short (Illumina HiSeq) read sequencing data

    Insights from the revised complete genome sequences of Acinetobacter baumannii strains AB307-0294 and ACICU belonging to global clones 1 and 2

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    © 2019 The Authors. The Acinetobacter baumannii global clone 1 isolate AB307-0294, recovered in the USA in 1994, and the global clone 2 (GC2) isolate ACICU, isolated in 2005 in Italy, were among the first A. baumannii isolates to be completely sequenced. AB307-0294 is susceptible to most antibiotics and has been used in many genetic studies, and ACICU belongs to a rare GC2 lineage. The complete genome sequences, originally determined using 454 pyrosequencing technology, which is known to generate sequencing errors, were re-determined using Illumina MiSeq and MinION (Oxford Nanopore Technologies) technologies and a hybrid assembly generated using Unicycler. Comparison of the resulting new high-quality genomes to the earlier 454-sequenced versions identified a large number of nucleotide differences affecting protein coding sequence (CDS) features, and allowed the sequences of the long and highly repetitive bap and blp1 genes to be properly resolved for the first time in ACICU. Comparisons of the annotations of the original and revised genomes revealed a large number of differences in the protein CDS features, underlining the impact of sequence errors on protein sequence predictions and core gene determination. On average, 400 predicted CDSs were longer or shorter in the revised genomes and about 200 CDS features were no longer present

    Z/i1 hybrid virulence plasmids carrying antimicrobial resistance genes in s. Typhimurium from australian food animal production

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    © MDPI AG. All rights reserved. Knowledge of mobile genetic elements that capture and disseminate antimicrobial resistance genes between diverse environments, particularly across human–animal boundaries, is key to understanding the role anthropogenic activities have in the evolution of antimicrobial resistance. Plasmids that circulate within the Enterobacteriaceae and the Proteobacteria more broadly are well placed to acquire resistance genes sourced from separate niche environments and provide a platform for smaller mobile elements such as IS26 to assemble these genes into large, complex genomic structures. Here, we characterised two atypical Z/I1 hybrid plasmids, pSTM32-108 and pSTM37-118, hosting antimicrobial resistance and virulence associated genes within endemic pathogen Salmonella enterica serovar Typhimurium 1,4,[5],12:i:-, sourced from Australian swine production facilities during 2013. We showed that the plasmids found in S. Typhimurium 1,4,[5],12:i:-are close relatives of two plasmids identified from Escherichia coli of human and bovine origin in Australia circa 1998. The older plasmids, pO26-CRL125 and pO111-CRL115, encoded a putative serine protease autotransporter and were host to a complex resistance region composed of a hybrid Tn21-Tn1721 mercury resistance transposon and composite IS26 transposon Tn6026. This gave a broad antimicrobial resistance profile keyed towards first generation antimicrobials used in Australian agriculture but also included a class 1 integron hosting the trimethoprim resistance gene dfrA5. Genes encoding resistance to ampicillin, trimethoprim, sulphonamides, streptomycin, aminoglycosides, tetracyclines and mercury were a feature of these plasmids. Phylogenetic analyses showed very little genetic drift in the sequences of these plasmids over the past 15 years; however, some alterations within the complex resistance regions present on each plasmid have led to the loss of various resistance genes, presumably as a result of the activity of IS26. These alterations may reflect the specific selective pressures placed on the host strains over time. Our studies suggest that these plasmids and variants of them are endemic in Australian food production systems

    Dynamical modeling of collective behavior from pigeon flight data: flock cohesion and dispersion

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    Several models of flocking have been promoted based on simulations with qualitatively naturalistic behavior. In this paper we provide the first direct application of computational modeling methods to infer flocking behavior from experimental field data. We show that this approach is able to infer general rules for interaction, or lack of interaction, among members of a flock or, more generally, any community. Using experimental field measurements of homing pigeons in flight we demonstrate the existence of a basic distance dependent attraction/repulsion relationship and show that this rule is sufficient to explain collective behavior observed in nature. Positional data of individuals over time are used as input data to a computational algorithm capable of building complex nonlinear functions that can represent the system behavior. Topological nearest neighbor interactions are considered to characterize the components within this model. The efficacy of this method is demonstrated with simulated noisy data generated from the classical (two dimensional) Vicsek model. When applied to experimental data from homing pigeon flights we show that the more complex three dimensional models are capable of predicting and simulating trajectories, as well as exhibiting realistic collective dynamics. The simulations of the reconstructed models are used to extract properties of the collective behavior in pigeons, and how it is affected by changing the initial conditions of the system. Our results demonstrate that this approach may be applied to construct models capable of simulating trajectories and collective dynamics using experimental field measurements of herd movement. From these models, the behavior of the individual agents (animals) may be inferred

    Emergence and rapid global dissemination of CTX-M-15-associated Klebsiella pneumoniae strain ST307

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    © 2019 Oxford University Press. All rights reserved. Objectives: Recent reports indicate the emergence of a new carbapenemase-producing Klebsiella pneumoniae clone, ST307. We sought to better understand the global epidemiology and evolution of this clone and evaluate its association with antimicrobial resistance (AMR) genes. Methods: We collated information from the literature and public databases and performed a comparative analysis of 95 ST307 genomes (including 37 that were newly sequenced). Results: We show that ST307 emerged in the mid-1990s (nearly 20 years prior to its first report), is already globally distributed and is intimately associated with a conserved plasmid harbouring the blaCTX-M-15 ESBL gene and several other AMR determinants. Conclusions: Our findings support the need for enhanced surveillance of this widespread ESBL clone in which carbapenem resistance has occasionally emerged

    Adjunctive long-acting risperidone in patients with bipolar disorder who relapse frequently and have active mood symptoms

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    <p>Abstract</p> <p>Background</p> <p>The objective of this exploratory analysis was to characterize efficacy and onset of action of a 3-month treatment period with risperidone long-acting injection (RLAI), adjunctive to an individual's treatment regimen, in subjects with symptomatic bipolar disorder who relapsed frequently and had significant symptoms of mania and/or depression.</p> <p>Methods</p> <p>Subjects with bipolar disorder with ≥4 mood episodes in the past 12 months entered the open-label stabilization phase preceding a placebo-controlled, double-blind study. Subjects with significant depressive or manic/mixed symptoms at baseline were analyzed. Significant depressive symptoms were defined as Montgomery-Åsberg Depression Rating Scale (MADRS) ≥16 and Young Mania Rating Scale (YMRS) < 16; manic/mixed symptoms were YMRS ≥16 with any MADRS score. Subjects received open-label RLAI (25-50 mg every 2 weeks) for 16 weeks, adjunctive to a subject's individualized treatment for bipolar disorder (mood stabilizers, antidepressants, and/or anxiolytics). Clinical status was evaluated with the Clinical Global Impressions of Bipolar Disorder-Severity (CGI-BP-S) scale and changes on the MADRS and YMRS scales. Within-group changes were evaluated using paired <it>t </it>tests; categorical differences were assessed using Fisher exact test. No adjustment was made for multiplicity.</p> <p>Results</p> <p>162 subjects who relapsed frequently met criteria for significant mood symptoms at open-label baseline; 59/162 (36.4%) had depressive symptoms, 103/162 (63.6%) had manic/mixed symptoms. Most subjects (89.5%) were receiving ≥1 medication for bipolar disorder before enrollment. Significant improvements were observed for the total population on the CGI-BP-S, MADRS, and YMRS scales (p < .001 vs. baseline, all variables). Eighty-two (53.3%) subjects achieved remission at the week 16 LOCF end point. The subpopulation with depressive symptoms at open-label baseline experienced significant improvement on the CGI-BP-S and MADRS scales (p < .001 vs. baseline, all variables). Subjects with manic/mixed symptoms at baseline had significant improvements on the CGI-BP-S and YMRS scales (p < .001 vs. baseline, all variables). No unexpected tolerability findings were observed.</p> <p>Conclusions</p> <p>Exploratory analysis of changes in overall clinical status and depression/mania symptoms in subjects with symptomatic bipolar disorder who relapse frequently showed improvements in each of these areas after treatment with RLAI, adjunctive to a subject's individualized treatment. Prospective controlled studies are needed to confirm these findings.</p

    Single Spin Asymmetry ANA_N in Polarized Proton-Proton Elastic Scattering at s=200\sqrt{s}=200 GeV

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    We report a high precision measurement of the transverse single spin asymmetry ANA_N at the center of mass energy s=200\sqrt{s}=200 GeV in elastic proton-proton scattering by the STAR experiment at RHIC. The ANA_N was measured in the four-momentum transfer squared tt range 0.003t0.0350.003 \leqslant |t| \leqslant 0.035 \GeVcSq, the region of a significant interference between the electromagnetic and hadronic scattering amplitudes. The measured values of ANA_N and its tt-dependence are consistent with a vanishing hadronic spin-flip amplitude, thus providing strong constraints on the ratio of the single spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated by the Pomeron amplitude at this s\sqrt{s}, we conclude that this measurement addresses the question about the presence of a hadronic spin flip due to the Pomeron exchange in polarized proton-proton elastic scattering.Comment: 12 pages, 6 figure

    Azimuthal anisotropy and correlations at large transverse momenta in p+pp+p and Au+Au collisions at sNN\sqrt{s_{_{NN}}}= 200 GeV

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    Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au+Au collisions at sNN\sqrt{s_{_{NN}}}= 200 GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au+Au collisions to those in p+pp+p at the same energy. Elliptic anisotropy, v2v_2, is found to reach its maximum at pt3p_t \sim 3 GeV/c, then decrease slowly and remain significant up to pt7p_t\approx 7 -- 10 GeV/c. Stronger suppression is found in the back-to-back high-ptp_t particle correlations for particles emitted out-of-plane compared to those emitted in-plane. The centrality dependence of v2v_2 at intermediate ptp_t is compared to simple models based on jet quenching.Comment: 4 figures. Published version as PRL 93, 252301 (2004

    Azimuthal anisotropy in Au+Au collisions at sqrtsNN = 200 GeV

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    The results from the STAR Collaboration on directed flow (v_1), elliptic flow (v_2), and the fourth harmonic (v_4) in the anisotropic azimuthal distribution of particles from Au+Au collisions at sqrtsNN = 200 GeV are summarized and compared with results from other experiments and theoretical models. Results for identified particles are presented and fit with a Blast Wave model. Different anisotropic flow analysis methods are compared and nonflow effects are extracted from the data. For v_2, scaling with the number of constituent quarks and parton coalescence is discussed. For v_4, scaling with v_2^2 and quark coalescence is discussed.Comment: 26 pages. As accepted by Phys. Rev. C. Text rearranged, figures modified, but data the same. However, in Fig. 35 the hydro calculations are corrected in this version. The data tables are available at http://www.star.bnl.gov/central/publications/ by searching for "flow" and then this pape

    Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au+Au collisions at sNN=19.6\sqrt{s_{NN}} = 19.6 and 200 GeV

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    The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity yee<1|y_{ee}|<1 in minimum-bias Au+Au collisions at sNN\sqrt{s_{NN}} = 19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ\rho spectral function for Mee<1.1M_{ee}<1.1 GeV/c2c^{2}. The integrated dielectron excess yield at sNN\sqrt{s_{NN}} = 19.6 GeV for 0.4<Mee<0.750.4<M_{ee}<0.75 GeV/c2c^2, normalized to the charged particle multiplicity at mid-rapidity, has a value similar to that in In+In collisions at sNN\sqrt{s_{NN}} = 17.3 GeV. For sNN\sqrt{s_{NN}} = 200 GeV, the normalized excess yield in central collisions is higher than that at sNN\sqrt{s_{NN}} = 17.3 GeV and increases from peripheral to central collisions. These measurements indicate that the lifetime of the hot, dense medium created in central Au+Au collisions at sNN\sqrt{s_{NN}} = 200 GeV is longer than those in peripheral collisions and at lower energies.Comment: 9 pages, 6 figure
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