21 research outputs found
Commonality among Fluoroquinolone-resistant sequence type ST131 extraintestinal Escherichia coli isolates from humans and companion animals in Australia
Get PDFEscherichia coli sequence type 131 (ST131), an emergent multidrug-resistant extraintestinal pathogen, has spread epidemically among humans and was recently isolated from companion animals. To assess for human-companion animal commonality among ST131 isolates, 214 fluoroquinolone-resistant extraintestinal E. coli isolates (205 from humans, 9 from companion animals) from diagnostic laboratories in Australia, provisionally identified as ST131 by PCR, selectively underwent PCR-based O typing and blaCTX-M-15 detection. A subset then underwent multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE) analysis, extended virulence genotyping, antimicrobial susceptibility testing, and fluoroquinolone resistance genotyping. All isolates were O25b positive, except for two O16 isolates and one O157 isolate, which (along with six O25b-positive isolates) were confirmed by MLST to be ST131. Only 12% of isolates (25 human, 1 canine) exhibited blaCTX-M-15. PFGE analysis of 20 randomly selected human and all 9 companion animal isolates showed multiple instances of ≥94% profile similarity across host species; 12 isolates (6 human, 6 companion animal) represented pulsotype 968, the most prevalent ST131 pulsotype in North America (representing 23% of a large ST131 reference collection). Virulence gene and antimicrobial resistance profiles differed minimally, without host species specificity. The analyzed ST131 isolates also exhibited a conserved, host species-independent pattern of chromosomal fluoroquinolone resistance mutations. However, eight (89%) companion animal isolates, versus two (10%) human isolates, possessed the plasmid-borne qnrB gene (P < 0.001). This extensive across-species strain commonality, plus the similarities between Australian and non-Australian ST131 isolates, suggest that ST131 isolates are exchanged between humans and companion animals both within Australia and intercontinentally.Joanne L. Platell, Rowland N. Cobbold, James R. Johnson, Anke Heisig, Peter Heisig, Connie Clabots, Michael A. Kuskowski and Darren J. Trot
Prominence of an O75 clonal group (clonal complex 14) among non-st131 fluoroquinolone-resistant Escherichia coli causing extraintestinal infections in humans and dogs in Australia
Get PDFFluoroquinolone (FQ)-resistant extraintestinal pathogenic Escherichia coli (FQ(r) ExPEC) strains from phylogenetic group B2 are undergoing epidemic spread. Isolates belonging to phylogenetic group B2 are generally more virulent than other E. coli isolates; therefore, resistance to FQs among group B2 isolates is concerning. Although clonal expansion of sequence type 131 (ST131) is a major factor, the contribution of additional clonal groups has not been quantified. Group B2 FQ(r) ExPEC isolates from humans (n = 250) and dogs (n = 12) in Australia were screened for ST131, a recently recognized and rapidly emerging multidrug-resistant and virulent clonal group that is important in both human and companion animal medicine. Non-ST131 isolates underwent virulence genotyping, PCR-based O typing, partial multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and FQ resistance mechanism analysis. Of 49 non-ST131 isolates (45 human, 4 canine), 49% (24 human, 2 canine) represented O-type O75 and exhibited conserved virulence genotypes (F10 papA allele, iha, fimH, sat, vat, fyuA, iutA, kpsMII, usp, ompT, malX, K1/K5 capsule) and MLST allele profiles corresponding with clonal complex CC14. Two clusters, each containing canine and human isolates, were identified by PFGE (differentiated by K1 and K5 capsules). Australian FQ(r) O75 isolates exhibited commonality with an historical FQ-susceptible O75 urosepsis isolate (also CC14). The isolation from humans and dogs of highly similar FQ(r) derivatives of the classic O75:K1/K5 (CC14) ExPEC lineage suggests recent acquisition of FQ resistance and potential cross-host-species transfer. This lineage should be targeted with ST131 in future epidemiological investigations of FQ(r) ExPEC.Joanne L. Platell, Darren J. Trott, James R. Johnson, Peter Heisig, Anke Heisig, Connie R. Clabots, Brian Johnston, and Rowland N. Cobbol
Uncomplicated Urinary Tract Infections and Antibiotic Resistance—Epidemiological and Mechanistic Aspects
No full textUncomplicated urinary tract infections are typically monobacterial and are predominantly caused by Escherichia coli. Although several effective treatment options are available, the rates of antibiotic resistance in urinary isolates of E. coli have increased during the last decade. Knowledge of the actual local rates of antibiotic resistant pathogens as well as the underlying mechanisms are important factors in addition to the geographical location and the health state of the patient for choosing the most effective antibiotic treatment. Recommended treatment options include trimethoprim alone or in combination with sulfamethoxazol, fluoroquinolones, β-lactams, fosfomycin-trometamol, and nitrofurantoin. Three basic mechanisms of resistance to all antibiotics are known, i.e., target alteration, reduced drug concentration and inactivation of the drug. These mechanisms—alone or in combination—contribute to resistance against the different antibiotic classes. With increasing prevalence, combinations of resistance mechanisms leading to multiple drug resistant (mdr) pathogens are being detected and have been associated with reduced fitness under in vitro situations. However, mdr clones among clinical isolates such as E. coli sequence type 131 (ST131) have successfully adapted in fitness and growth rate and are rapidly spreading as a worldwide predominating clone of extraintestinal pathogenic E. coli
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International Conference on Knowledge Management
Get PDFQuantum physics surpasses human imagination. It totally contradicts everyday experiences. Even literal and mathematical explanations cannot substitute for a non-intuitive behavior that puzzles many of us. Commercial quantum computers are in reach within this decade. History provides examples that the appearance of new technologies brought metaphors to life that may explain up to that point poorly understood knowledge domains (e.g., "brains are hardware while thoughts are software"). The author describes why the proliferation of quantum computers will be accompanied by the rise of metaphors that explain quantum effects. For one, those might help to better communicate about the best use and consequences of quantum computers. But those metaphors could also shed light on organizational performance at all. To show a practical example, the author proposes how the use of quantum metaphors could help organizations to prepare for the quantum computing era - without being exact in predictions about most likely technical implementation of quantum capabilities
Knowledge Management Essentials
No full textReflecting on the history and development of the knowledge management discipline from an academic and applied research perspective, this chapter will outline the KM essentials as core of the discipline and open questions to be addressed in the future. Secondly, the author will discuss in particular the role of KM within organizational practice in regard to the overall societal challenges all organizations are facing today globally. Thirdly, the chapter will provide an outlook of the discipline in the light of future developments and suggests some research topics to be addressed by interdisciplinary KM research in the future. Beside on drawing on more than 35 years of experience in the KM field, this contribution will profit from previous research undertaken on the future of KM (2002 and 2012), contributions to guidelines and standards for KM (e.g., CEN, DIN, ISO), as well as from working with European Fortune 500 companies over the past 25 years
A Brief Guide for the Creation of Author-specific Citation Metrics and Publication Data Using the Thomson Reuters Web of Science and Scopus Databases
Get PDFThe objective of this guide is twofold. First, it shall enable interested readers to understand and reproduce the process of collecting author-specific citation metrics and publication data from the Thomson Reuters Web of Science and Scopus databases that is adopted in Andreoli-Versbach and Mueller-Langer (2013). Second, it presents the problems faced during the data collection process and the refined method of data collection we adopt to address related concerns. Thereby, it may serve interested readers as a guideline to accurately and efficiently retrieve citation metrics and publication information from Thomson Reuters Web of Science and Scopus in similar endeavors
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International Conference on Knowledge Management
Get PDFThe 17th International Conference on Knowledge Management was held in the historic city of Potsdam, Germany. Since the conference was among the first post-pandemic face to face conferences, the overall theme of the 17th edition of the ICKM conference rightly focused on “Knowledge, Uncertainty and Risks: From individual to global scale” at different levels of analysis and agency. This document highlighted one of the keynote speeches by Dave Snowden is the founder of one of the five schools of sense-making, and takes an approach which draws heavily on natural science, in particular complex adaptive systems theory, cognitive neuroscience and the biological end of anthropology. He is the creator of the Cynefin framework and lead author of the recently published EU Field Guide to managing complexity
Antibacterial activity of finafloxacin under different pH conditions against isogenic strains of Escherichia coli expressing combinations of defined mechanisms of fluoroquinolone resistance
No full textThe antirepressor of phage P1 Isolation and interaction with the C1 repressor of P1 and P7
No full textAbstractTwo antirepressor proteins, Ant1 and Ant2, of molecular weight 42 and 32 kDa, respectively, are encoded by P1 as a single open reading frame, with the smaller protein initiating at an in-frame start codon. Another open reading frame, icd, 5′ upstream of and overlapping ant1 is required for ant1 expression. Using appropriate ant gene-carrying plasmids we have overproduced and purified Ant12 in the form of a protein complex and Ant2 as a single protein. Sequence analysis confirmed the N-terminal amino acids predicted from the DNA sequence of ant1/ant2, except that the N-terminal methionine is missing in the Ant2 protein. Under appropriate conditions the C1 repressors of phages P1 and P7 specifically co-precipitate with the Ant12 complex but not with Ant2 protein alone. The results suggest that the antirepressor may exert its C1-inactivating function by a direct protein—protein interaction
