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Using genomic DNA-based probe-selection to improve the sensitivity of high-density oligonucleotide arrays when applied to heterologous species
High-density oligonucleotide (oligo) arrays are a powerful tool for transcript profiling. Arrays based on GeneChip® technology are amongst the most widely used, although GeneChip® arrays are currently available for only a small number of plant and animal species. Thus, we have developed a method to improve the sensitivity of high-density oligonucleotide arrays when applied to heterologous species and tested the method by analysing the transcriptome of Brassica oleracea L., a species for which no GeneChip® array is available, using a GeneChip® array designed for Arabidopsis thaliana (L.) Heynh. Genomic DNA from B. oleracea was labelled and hybridised to the ATH1-121501 GeneChip® array. Arabidopsis thaliana probe-pairs that hybridised to the B. oleracea genomic DNA on the basis of the perfect-match (PM) probe signal were then selected for subsequent B. oleracea transcriptome analysis using a .cel file parser script to generate probe mask files. The transcriptional response of B. oleracea to a mineral nutrient (phosphorus; P) stress was quantified using probe mask files generated for a wide range of gDNA hybridisation intensity thresholds. An example probe mask file generated with a gDNA hybridisation intensity threshold of 400 removed > 68 % of the available PM probes from the analysis but retained >96 % of available A. thaliana probe-sets. Ninety-nine of these genes were then identified as significantly regulated under P stress in B. oleracea, including the homologues of P stress responsive genes in A. thaliana. Increasing the gDNA hybridisation intensity thresholds up to 500 for probe-selection increased the sensitivity of the GeneChip® array to detect regulation of gene expression in B. oleracea under P stress by up to 13-fold. Our open-source software to create probe mask files is freely available http://affymetrix.arabidopsis.info/xspecies/ webcite and may be used to facilitate transcriptomic analyses of a wide range of plant and animal species in the absence of custom arrays
Ink release and swimming behavior in the oceanic Ctenophore Eurhamphaea vexilligera
Author Posting. © University of Chicago, 2020. This article is posted here by permission of University of Chicago for personal use, not for redistribution. The definitive version was published in Biological Bulletin 238(3), (2020): 206-213. doi:10.1086/709504.Of the more than 150 ctenophore species, the oceanic ctenophore Eurhamphaea vexilligera is notable for its bright orange-yellow ink, secreted from numerous small vesicles that line its substomodeal comb rows. To date, in situ observations by scuba divers have proved the most fruitful method of observing these animals’ natural behavior. We present the results of one such contemporary scuba-based observation of E. vexilligera, conducted in the Gulf Stream waters off the coast of Florida, using high-resolution photography and video. Utilizing underwater camera systems purpose built for filming gelatinous zooplankton, we observed E. vexilligera ink release and swimming behavior in situ. From these data, we describe the timeline and mechanics of E. vexilligera ink release in detail, as well as the animal’s different swimming behaviors and resulting ink dispersal patterns. We also describe a rolling swimming behavior, accompanied and possibly facilitated by a characteristic change in overall body shape. These observations provide further insight into the behavioral ecology of this distinctive ctenophore and may serve as the foundation for future kinematic studies.This work was funded by National Science Foundation awards OCE-1829945 to BJG, OCE-1829932 to KRS, OCE-1829913 to SPC, and OCE-1830015 to JHC. We thank the captain and crew of Calypso Dive Charters’ Miss Jackie for their assistance and field expertise, as well as two anonymous reviewers, whose insightful comments have improved the quality of the manuscript
Network approaches for formalizing conceptual models in ecosystem-based management
Funding Intermodel comparisons were supported through funding from the NOAA Integrated Ecosystem Assessment Program. P.S. McDonald’s involvement was funded in part by a grant from Washington Sea Grant, University of Washington, pursuant to National Oceanic and Atmospheric Administration Award number NA14OAR4170078. Funding for RPW was supported by the National Marine Fisheries Service (NMFS)/Sea Grant Population and Ecosystem Dynamics Graduate Fellowship via federal award NA14OAR4170077. Acknowledgements We would like to acknowledge and thank the participants of the NOAA Integrated Ecosystem Assessment Program conceptual network modelling workshop at Baton Rouge, LA in July 2018. The discussions at this meeting formed some of the basis for the ideas presented in this manuscript. We also thank J. Moss and two anonymous reviewers for valuable comments on earlier manuscript drafts. The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the National Marine Fisheries Service, NOAA. Reference to trade names does not imply endorsement by the National Marine Fisheries Service, NOAA. This is NOAA Integrated Ecosystem Assessment Program contribution number 2021_3.Peer reviewedPostprin
Effects of Arteriovenous Fistula on Blood Pressure in Patients With End-Stage Renal Disease: A Systematic Meta-Analysis
Background Central arteriovenous fistula ( AVF ) creation is under investigation for treatment of severe hypertension. We evaluated the effects of AVF for initiation of hemodialysis on systolic, diastolic, and mean arterial blood pressure in patients with end-stage renal disease. Methods and Results Data search included PubMed, Web of Science, and the Cochrane Library. A systematic review and meta-analysis of peer-reviewed studies reporting the effects of the creation/ligation of an AVF on blood pressure in patients with end-stage renal disease was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis), PRISMA -P (PRISMA for systematic review protocols), and ROBINS-I (Risk of Bias in Non-Randomized Studies) criteria by the Cochrane Bias Methods Group. All studies in which the results could have been biased by hemodialysis were excluded. A total of 14 trials including 412 patients with end-stage renal disease ( AVF creation, n=185; AVF ligation, n=227) fulfilled the criteria and were subsequently analyzed. Average blood pressure in patients with no/closed AVF was 140.5/77.6 mm Hg with a mean arterial blood pressure of 96.1 mm Hg. Following creation of AVF , systolic blood pressure significantly decreased by 8.7 mm Hg ( P<0.001), diastolic blood pressure by 5.9 mm Hg ( P<0.001), and mean arterial blood pressure by 6.6 mm Hg ( P=0.02), whereas after ligation systolic blood pressure increased by 5.2 mm Hg ( P=0.07), diastolic blood pressure by 3.8 mm Hg ( P=0.02), and mean arterial blood pressure by 3.7 mm Hg ( P=0.07) during short- to long-term follow-up. Conclusions Creation of AVF significantly decreases blood pressure in patients with end-stage renal disease, whereas blood pressure tends to increase after ligation. These findings illustrate the hemodynamic consequences of AVF which are under investigation for severe hypertension
Potential distributions of Bacillus anthracis and Bacillus cereus biovar anthracis causing anthrax in Africa
Background
Bacillus cereus biovar anthracis (Bcbva) is an emergent bacterium closely related to Bacillus anthracis, the etiological agent of anthrax. The latter has a worldwide distribution and usually causes infectious disease in mammals associated with savanna ecosystems. Bcbva was identified in humid tropical forests of Côte d’Ivoire in 2001. Here, we characterize the potential geographic distributions of Bcbva in West Africa and B. anthracis in sub-Saharan Africa using an ecological niche modeling approach.
Methodology/Principal findings
Georeferenced occurrence data for B. anthracis and Bcbva were obtained from public data repositories and the scientific literature. Combinations of temperature, humidity, vegetation greenness, and soils values served as environmental variables in model calibrations. To predict the potential distribution of suitable environments for each pathogen across the study region, parameter values derived from the median of 10 replicates of the best-performing model for each pathogen were used. We found suitable environments predicted for B. anthracis across areas of confirmed and suspected anthrax activity in sub-Saharan Africa, including an east-west corridor from Ethiopia to Sierra Leone in the Sahel region and multiple areas in eastern, central, and southern Africa. The study area for Bcbva was restricted to West and Central Africa to reflect areas that have likely been accessible to Bcbva by dispersal. Model predicted values indicated potential suitable environments within humid forested environments. Background similarity tests in geographic space indicated statistical support to reject the null hypothesis of similarity when comparing environments associated with B. anthracis to those of Bcbva and when comparing humidity values and soils values individually. We failed to reject the null hypothesis of similarity when comparing environments associated with Bcbva to those of B. anthracis, suggesting that additional investigation is needed to provide a more robust characterization of the Bcbva niche.
Conclusions/Significance
This study represents the first time that the environmental and geographic distribution of Bcbva has been mapped. We document likely differences in ecological niche—and consequently in geographic distribution—between Bcbva and typical B. anthracis, and areas of possible co-occurrence between the two. We provide information crucial to guiding and improving monitoring efforts focused on these pathogens
BPS Domain Wall Junctions in Infinitely Large Extra Dimensions
We consider models of scalar fields coupled to gravity which are
higher-dimensional generalizations of four dimensional supergravity. We use
these models to describe domain wall junctions in an anti-de Sitter background.
We derive Bogomolnyi equations for the scalar fields from which the walls are
constructed and for the metric. From these equations a BPS-like formula for the
junction energy can be derived. We demonstrate that such junctions localize
gravity in the presence of more than one uncompactified extra dimension.Comment: 17 pages, uses RevTeX, new references adde
Models of Forbidden Line Emission Profiles from Axisymmetric Stellar Winds
A number of strong infrared forbidden lines have been observed in several
evolved Wolf-Rayet star winds, and these are important for deriving metal
abundances and testing stellar evolution models. In addition, because these
optically thin lines form at large radius in the wind, their resolved profiles
carry an imprint of the asymptotic structure of the wind flow. This work
presents model forbidden line profile shapes formed in axisymmetric winds. It
is well-known that an optically thin emission line formed in a spherical wind
expanding at constant velocity yields a flat-topped emission profile shape.
Simulated forbidden lines are produced for a model stellar wind with an
axisymmetric density distribution that treats the latitudinal ionization
self-consistently and examines the influence of the ion stage on the profile
shape. The resulting line profiles are symmetric about line centre. Within a
given atomic species, profile shapes can vary between centrally peaked, doubly
peaked, and approximately flat-topped in appearance depending on the ion stage
(relative to the dominant ion) and viewing inclination. Although application to
Wolf-Rayet star winds is emphasized, the concepts are also relevant to other
classes of hot stars such as luminous blue variables and Be/B[e] stars.Comment: To appear in MNRA
The Surviving Sepsis Campaign: results of an international guideline-based performance improvement program targeting severe sepsis
Objective: The Surviving Sepsis Campaign (SSC or “the Campaign”) developed guidelines for management of severe sepsis and septic shock. A performance improvement initiative targeted changing clinical behavior (process improvement) via bundles based on key SSC guideline recommendations on process improvement and patient outcomes. Design and setting: A multifaceted intervention to facilitate compliance with selected guideline recommendations in the ICU, ED, and wards of individual hospitals and regional hospital networks was implemented voluntarily in the US, Europe, and South America. Elements of the guidelines were “bundled” into two sets of targets to be completed within 6 h and within 24 h. An analysis was conducted on data submitted from January 2005 through March 2008. Main results: Data from 15,022 subjects at 165 sites were analyzed to determine the compliance with bundle targets and association with hospital mortality. Compliance with the entire resuscitation bundle increased linearly from 10.9% in the first site quarter to 31.3% by the end of 2 years (P < 0.0001). Compliance with the entire management bundle started at 18.4% in the first quarter and increased to 36.1% by the end of 2 years (P = 0.008). Compliance with all bundle elements increased significantly, except for inspiratory plateau pressure, which was high at baseline. Unadjusted hospital mortality decreased from 37 to 30.8% over 2 years (P = 0.001). The adjusted odds ratio for mortality improved the longer a site was in the Campaign, resulting in an adjusted absolute drop of 0.8% per quarter and 5.4% over 2 years (95% CI, 2.5–8.4%). Conclusions: The Campaign was associated with sustained, continuous quality improvement in sepsis care. Although not necessarily cause and effect, a reduction in reported hospital mortality rates was associated with participation. The implications of this study may serve as an impetus for similar improvement efforts.Electronic supplementary material The online version of this article (doi:10.1007/s00134-009-1738-3) contains supplementary material, which is available to authorized users
Clinical characteristics and outcomes of patients with acute myelogenous leukemia admitted to intensive care: a case-control study
<p>Abstract</p> <p>Background</p> <p>There is limited epidemiologic data on patients with acute myelogenous (myeloid) leukemia (AML) requiring life-sustaining therapies in the intensive care unit (ICU). Our objectives were to describe the clinical characteristics and outcomes in critically ill AML patients.</p> <p>Methods</p> <p>This was a retrospective case-control study. Cases were defined as adult patients with a primary diagnosis of AML admitted to ICU at the University of Alberta Hospital between January 1<sup>st </sup>2002 and June 30<sup>th </sup>2008. Each case was matched by age, sex, and illness severity (ICU only) to two control groups: hospitalized AML controls, and non-AML ICU controls. Data were extracted on demographics, course of hospitalization, and clinical outcomes.</p> <p>Results</p> <p>In total, 45 AML patients with available data were admitted to ICU. Mean (SD) age was 54.8 (13.1) years and 28.9% were female. Primary diagnoses were sepsis (32.6%) and respiratory failure (37.3%). Mean (SD) APACHE II score was 30.3 (10.3), SOFA score 12.6 (4.0) with 62.2% receiving mechanical ventilation, 55.6% vasoactive therapy, and 26.7% renal replacement therapy. Crude in-hospital, 90-day and 1-year mortality was 44.4%, 51.1% and 71.1%, respectively. AML cases had significantly higher adjusted-hazards of death (HR 2.23; 95% CI, 1.38-3.60, p = 0.001) compared to both non-AML ICU controls (HR 1.69; 95% CI, 1.11-2.58, p = 0.02) and hospitalized AML controls (OR 1.0, reference variable). Factors associated with ICU mortality by univariate analysis included older age, AML subtype, higher baseline SOFA score, no change or an increase in early SOFA score, shock, vasoactive therapy and mechanical ventilation. Active chemotherapy in ICU was associated with lower mortality.</p> <p>Conclusions</p> <p>AML patients may represent a minority of all critically ill admissions; however, are not uncommonly supported in ICU. These AML patients are characterized by high illness severity, multi-organ dysfunction, and high treatment intensity and have a higher risk of death when compared with matched hospitalized AML or non-AML ICU controls. The absence of early improvement in organ failure may be a useful predictor for mortality for AML patients admitted to ICU.</p
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