38 research outputs found

    The cnidarian-bilaterian ancestor possessed at least 56 homeoboxes: evidence from the starlet sea anemone, Nematostella vectensis

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    BACKGROUND: Homeodomain transcription factors are key components in the developmental toolkits of animals. While this gene superclass predates the evolutionary split between animals, plants, and fungi, many homeobox genes appear unique to animals. The origin of particular homeobox genes may, therefore, be associated with the evolution of particular animal traits. Here we report the first near-complete set of homeodomains from a basal (diploblastic) animal. RESULTS: Phylogenetic analyses were performed on 130 homeodomains from the sequenced genome of the sea anemone Nematostella vectensis along with 228 homeodomains from human and 97 homeodomains from Drosophila. The Nematostella homeodomains appear to be distributed among established homeodomain classes in the following fashion: 72 ANTP class; one HNF class; four LIM class; five POU class; 33 PRD class; five SINE class; and six TALE class. For four of the Nematostella homeodomains, there is disagreement between neighbor-joining and Bayesian trees regarding their class membership. A putative Nematostella CUT class gene is also identified. CONCLUSION: The homeodomain superclass underwent extensive radiations prior to the evolutionary split between Cnidaria and Bilateria. Fifty-six homeodomain families found in human and/or fruit fly are also found in Nematostella, though seventeen families shared by human and fly appear absent in Nematostella. Homeodomain loss is also apparent in the bilaterian taxa: eight homeodomain families shared by Drosophila and Nematostella appear absent from human (CG13424, EMXLX, HOMEOBRAIN, MSXLX, NK7, REPO, ROUGH, and UNC4), and six homeodomain families shared by human and Nematostella appear absent from fruit fly (ALX, DMBX, DUX, HNF, POU1, and VAX)

    Origin of Secretin Receptor Precedes the Advent of Tetrapoda: Evidence on the Separated Origins of Secretin and Orexin

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    At present, secretin and its receptor have only been identified in mammals, and the origin of this ligand-receptor pair in early vertebrates is unclear. In addition, the elusive similarities of secretin and orexin in terms of both structures and functions suggest a common ancestral origin early in the vertebrate lineage. In this article, with the cloning and functional characterization of secretin receptors from lungfish and X. laevis as well as frog (X. laevis and Rana rugulosa) secretins, we provide evidence that the secretin ligand-receptor pair has already diverged and become highly specific by the emergence of tetrapods. The secretin receptor-like sequence cloned from lungfish indicates that the secretin receptor was descended from a VPAC-like receptor prior the advent of sarcopterygians. To clarify the controversial relationship of secretin and orexin, orexin type-2 receptor was cloned from X. laevis. We demonstrated that, in frog, secretin and orexin could activate their mutual receptors, indicating their coordinated complementary role in mediating physiological processes in non-mammalian vertebrates. However, among the peptides in the secretin/glucagon superfamily, secretin was found to be the only peptide that could activate the orexin receptor. We therefore hypothesize that secretin and orexin are of different ancestral origins early in the vertebrate lineage

    Video recording in veterinary medicine OSCEs: Feasibility and inter-rater agreement between live performance examiners and video recording reviewing examiners

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    Catriona Bell – ORCID: 0000-0001-8501-1697 https://orcid.org/0000-0001-8501-1697Item not available in this repository.The Objective Structured Clinical Examination (OSCE) is a valid, reliable assessment of veterinary students’ clinical skills that requires significant examiner training and scoring time. This article seeks to investigate the utility of implementing video recording by scoring OSCEs in real-time using live examiners, and afterwards using video examiners from within and outside the learners’ home institution. Using checklists, learners (n=33) were assessed by one live examiner and five video examiners on three OSCE stations: suturing, arthrocentesis, and thoracocentesis. When stations were considered collectively, there was no difference between pass/fail outcome between live and video examiners (χ2 = 0.37, p = .55). However, when considered individually, stations (χ2 = 16.64, p < .001) and interaction between station and type of examiner (χ2 = 7.13, p = .03) demonstrated a significant effect on pass/fail outcome. Specifically, learners being assessed on suturing with a video examiner had increased odds of passing the station as compared with their arthrocentesis or thoracocentesis stations. Internal consistency was fair to moderate (0.34–0.45). Inter-rater reliability measures varied but were mostly moderate to strong (0.56–0.82). Video examiners spent longer assessing learners than live raters (mean of 21 min/learner vs. 13 min/learner). Station-specific differences among video examiners may be due to intermittent visibility issues during video capture. Overall, video recording learner performances appears reliable and feasible, although there were time, cost, and technical issues that may limit its routine use.https://doi.org/10.3138/jvme-2019-014248pubpub

    Trends in incidence and clinical outcomes of Clostridioides difficile infection, Hong Kong

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    We conducted a territorywide survey to investigate the epidemiology, risk factors, and clinical outcomes of Clostridioides difficile infection (CDI) among hospitalized patients in Hong Kong. A total of 17,105 cases of CDI were identified, of which 15,717 (91.9%) were healthcare-associated and 1,025 (6.0%) were community-associated. Although CDI incidence increased substantially from 2006 to 2017, it plateaued in 2018 and 2019. The 30-day mortality rates decreased from 20.1% in 2015 to 16.8% in 2019, whereas the 60-day recurrence rates remained constant at ≈11% during the study period. Cross-correlation statistic showed significant correlations between incidence trend and overall antimicrobial drug use (r = 0.865, p<0.001), which has decreased as a result of an antibiotic stewardship program initiated in 2017. Our data suggest a turning point in C. difficile epidemiology that could be related to the changing pattern of antimicrobial drug use.Published versionThis project is supported by the Hong Kong University Grants Committee Research Grant Council (Early Career Scheme no. 21153816/24103516) and the Hong Kong Food and Health Bureau Commissioned Health and Medical Research Fund (CID-CUHK-C)

    ‘The ice edge is lost … nature moved it’: mapping ice as state practice in the Canadian and Norwegian North

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    This paper explores how ‘ice’ is woven into the spaces and practices of the state in Norway and Canada and, specifically, how representations of the sea ice edge become political agents in that process. We focus in particular on how these states have used science to ‘map’ sea ice – both graphically and legally – over the past decades. This culminated with two maps produced in 2015, a Norwegian map that moved the Arctic sea-ice edge 70 km northward and a Canadian map that moved it 200 km southward. Using the maps and their genealogies to explore how designations of sea ice are entangled with political objectives (oil drilling in Norway, sovereignty claims in Canada), we place the maps within the more general tendency of states to assign fixed categories to portions of the earth's surface and define distinct lines between them. We propose that the production of static ontologies through cartographic representations becomes particularly problematic in an icy environment of extraordinary temporal and spatial dynamism, where complex ocean–atmospheric processes and their biogeographic impacts are reduced to lines on a map
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