Ancient DNA Suggests Dwarf and ‘Giant’ Emu Are Conspecific

) is unclear. King Island Emu were mainly distinguished by their much smaller size and a reported darker colour compared to modern Emu. oxidase subunit I (COI) region (1,544 bp), as well as a region of the melanocortin 1 receptor gene (57 bp) were sequenced using a multiplex PCR approach. The results show that haplotypes for King Island Emu fall within the diversity of modern Emu.These data show the close relationship of these emu when compared to other congeneric bird species and indicate that the King Island and modern Emu share a recent common ancestor. King Island emu possibly underwent insular dwarfism as a result of phenotypic plasticity. The close relationship between the King Island and the modern Emu suggests it is most appropriate that the former should be considered a subspecies of the latter. Although both taxa show a close genetic relationship they differ drastically in size. This study also suggests that rates of morphological and neutral molecular evolution are decoupled

Comparison of five methods for detection of carbapenemases in Enterobacterales with proposal of a new algorithm

Objectives: The aim of this study was to evaluate the performance of five different carbapenemase tests and to develop an algorithm which will permit the detection of most common and rare carbapenemases in routine microbiology laboratories. Methods: The immunochromatographic tests CARBA-5 (NG), RESIST-4 O.K.N.V. (Coris), the colorimetric beta-CARBA (BioRad), a newly developed carbapenem-inactivation method (CIM) supplemented with zinc (zCIM), and the Xpert Carba-R (Cepheid) were challenged with a collection of 189 molecularly characterized Enterobacterales isolates, including 146 carbapenemase producers (CPE): VIM (n = 48), OXA-48-like (n = 40), NDM (n = 29), KPC (n = 13), IMI (n = 9), IMP (n = 9), OXA-58 (n = 2), and GES (n = 2). Results: The overall sensitivity/specificity values for the five carbapenemase detection tests were 84.2% (CI 77.6-89.2%)/100% (CI 91.8-100%) for RESIST-4, 88.2% (CI 82.1-92.4%)/100% (CI 91.8-100%) for CARBA-5, 88.2% (CI 82.1-92.4%)/100% (CI 91.8-100%) for Xpert Carba-R, 73.7% (CI 66.2-80.0%)/100% (CI 93.4-99.0%) for beta-CARBA, and 97.4% (CI 87.9-99.6%)/97.7% (CI 87.9-99.6%) for zCIM. The four common carbapenemases (KPC, OXA-48-like, NDM, and VIM) were detected with >= 97.6% sensitivity by all tests except for beta-CARBA (76.6% (CI 68.4-83.2%)). IMI and GES were only detected by zCIM (sensitivity 90.9% (CI 62.3-98.4%)). Based on these results a new algorithm was developed, consisting of an immunochromatographic assay as the first test followed by zCIM, which allows detection of 99.3% of all carbapenemases assessed. Conclusions: Except for beta-CARBA, all methods showed excellent sensitivity/specificity for the detection of the four most frequent carbapenemases. With the new algorithm, rare variants can also be detected. It is rapid, simple, and inexpensive and can be performed in any microbiology laboratory, as no PCR equipment is required. L. Lucena Baeza, Clin Microbiol Infect 2019;25:1286.e9-1286.e15 (c) 2019 The Authors. Published by Elsevier Ltd on behalf of European Society of Clinical Microbiology and Infectious Diseases. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Evaluation of six commercial products for colistin susceptibility testing in Enterobacterales

Objectives: The recommended technique for colistin susceptibility testing by both EUCAST and CLSI is broth microdilution (BMD). However, many routine laboratories still use other methods such as gradient strips or semi-automated systems. The objective of this study was to compare six of the most widespread commercial products for colistin susceptibility testing in Europe with in-house prepared BMD. Methods: A collection of 325 carbapenemase-producing Enterobacterales was tested for colistin susceptibility with three semi-automated systems (Vitek 2, BD Phoenix, MicroScan WalkAway), one gradient-strip test (Etest (R)) and two commercial BMD products (MICRONAUT-S, TREK Sensititre). BMD, in-house prepared according to ISO standard 20776-1, served as reference. Results: The MICRONAUT-S BMD performed best with only one false-resistant (major error, ME) and four false-susceptible (very major error, VME) results while the TREK BMD performed poorer with 16 ME and seven VME. The semi-automated systems Vitek 2 and Phoenix performed poorly with 31 and 26 VME, respectively. The WalkAway semi-automated system showed 16 and 13 false results, depending on the inoculation method. The Etest (R) showed six ME and 10 VME. Conclusions: This study shows that colistin susceptibility testing remains a challenging task for laboratories. It emphasizes the need for selecting the most reliable test method to advocate proper treatment and shows that critical evaluation and precautious usage of colistin susceptibility testing results is constantly required. (C) 2019 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved