702 research outputs found
MRI-based Surgical Planning for Lumbar Spinal Stenosis
The most common reason for spinal surgery in elderly patients is lumbar
spinal stenosis(LSS). For LSS, treatment decisions based on clinical and
radiological information as well as personal experience of the surgeon shows
large variance. Thus a standardized support system is of high value for a more
objective and reproducible decision. In this work, we develop an automated
algorithm to localize the stenosis causing the symptoms of the patient in
magnetic resonance imaging (MRI). With 22 MRI features of each of five spinal
levels of 321 patients, we show it is possible to predict the location of
lesion triggering the symptoms. To support this hypothesis, we conduct an
automated analysis of labeled and unlabeled MRI scans extracted from 788
patients. We confirm quantitatively the importance of radiological information
and provide an algorithmic pipeline for working with raw MRI scans
Hydrogen sulfide protects renal grafts against prolonged cold ischemia-reperfusion injury via specific mitochondrial actions
This article has been accepted for publication and undergone full peer review but has not been
through the copyediting, typesetting, pagination and proofreading process, which may lead to
differences between this version and the Version of Record. Please cite this article as doi:
10.1111/ajt.14080
This article is protected by copyright. All rights reserved.Accepted manuscript online:
15 October 2016Ischemia-reperfusion injury (IRI) is unavoidably caused by loss and subsequent restoration of blood flow during organ procurement and prolonged IRI results in increased rates of delayed graft function and early graft loss. The endogenously produced gasotransmitter, hydrogen sulfide (H2 S), is a novel molecule that mitigates hypoxic tissue injury. The current study investigates the protective mitochondrial effects of H2 S during in vivo cold storage and subsequent renal transplantation (RTx) and in vitro cold hypoxic renal injury. Donor allografts from Brown Norway rats treated with University of Wisconsin (UW) solution + H2 S (150 ΌM NaSH) during prolonged (24-hour) cold (4°C) storage exhibited significantly (p1000-fold compared to similar levels of the non-specific H2 S donor, GYY4137 and also improved syngraft function and survival following prolonged cold storage compared to UW. H2 S treatment mitigates cold IRI-associated renal injury via mitochondrial actions and could represent a novel therapeutic strategy to minimize the detrimental clinical outcomes of prolonged cold IRI during RTx.This work was supported by grants from Physicians Services Incorporated and the Canadian
Urological Association (AS) and by a Frederick Banting and Charles Best Canada Graduate
Scholarships Doctoral Award from the Canadian Institutes of Health Research (IL). MW and
MEW would like to thank the Medical Research Council UK (MR/M022706/1) for their
generous research support. RT would like to acknowledge the Brian Ridge Scholarship for
support
Planning and Leveraging Event Portfolios: Towards a Holistic Theory
This conceptual paper seeks to advance the discourse on the leveraging and legacies of events by examining the planning, management, and leveraging of event portfolios. This examination shifts the common focus from analyzing single events towards multiple events and purposes that can enable cross-leveraging among different events in pursuit of attainment and magnification of specific ends. The following frameworks are proposed: (1) event portfolio planning and leveraging, and (2) analyzing events networks and inter-organizational linkages. These frameworks are intended to provide, at this infancy stage of event portfolios research, a solid ground for building theory on the management of different types and scales of events within the context of a portfolio aimed to obtain, optimize and sustain tourism, as well as broader community benefits
GYY4137, a slow-releasing hydrogen sulfide donor, ameliorates renal damage associated with chronic obstructive uropathy.
PURPOSE: Chronic obstructive uropathy can cause irreversible kidney injury, atrophy, and inflammation, which can ultimately lead to fibrosis. Epithelial-mesenchymal transition (EMT) is a key trigger of fibrosis and is caused by upregulation of transforming growth factor beta 1 (TGF-ÎČ1) and angiotensin II (ANGII). Hydrogen sulfide (H2S) is an endogenously produced gasotransmitter with cytoprotective properties. The present study aims to elucidate the effects of the slow-releasing H2S donor GYY4137 on chronic ureteral obstruction and evaluate potential mechanisms. MATERIALS AND METHODS: Following unilateral ureteral obstruction (UUO), male Lewis rats were given daily intraperitoneal (IP) administration of phosphate buffered saline (PBS) vehicle (UUO group) or PBS+200ÎŒmol/kg GYY4137 (UUO+GYY4137 group) for 30 days. Urine and serum samples were collected to determine physiological parameters of renal function and injury. Kidneys were removed on post-operative day 30 for evaluation of histopathology and protein expression. EMT in pig kidney epithelial cells (LLC-PK1) was induced with TGF-ÎČ1 and treated with GYY4137 to evaluate potential mechanisms via in vitro scratch wound assays. RESULTS: H2S treatment decreased serum creatinine and urine protein/creatinine excretion ratio following UUO. In addition, H2S mitigated cortical loss, inflammatory damage, and tubulointerstitial fibrosis. Tissues exhibited decreased expression of EMT markers upon H2S treatment. EMT progression in LLC-PK1 was alleviated upon in vitro administration of GYY4137. CONCLUSIONS: Our findings demonstrate, for the first time, the protective effects of H2S in chronic obstructive uropathy and may represent a potential therapeutic solution to ameliorate renal damage and improve clinical outcomes of urinary obstruction.This work was supported by a grant from the Lawson Health Research Foundation
Inactivated Parapoxvirus ovis induces a transient increase in the expression of proinflammatory, Th1-related, and autoregulatory cytokines in mice
Language vs individuals in cross-linguistic corpus typology
Published as a special publication of Language Documentation & Conservation (No. 25).Peer reviewe
The Self Model and the Conception of Biological Identity in Immunology
The self/non-self model, first proposed by F.M. Burnet, has dominated immunology for sixty years now. According to this model, any foreign element will trigger an immune reaction in an organism, whereas endogenous elements will not, in normal circumstances, induce an immune reaction. In this paper we show that the self/non-self model is no longer an appropriate explanation of experimental data in immunology, and that this inadequacy may be rooted in an excessively strong metaphysical conception of biological identity. We suggest that another hypothesis, one based on the notion of continuity, gives a better account of immune phenomena. Finally, we underscore the mapping between this metaphysical deflation from self to continuity in immunology and the philosophical debate between substantialism and empiricism about identity
Deep 1.1 mm-wavelength imaging of the GOODS-S field by AzTEC/ASTE - I. Source catalogue and number counts
[Abridged] We present the first results from a 1.1 mm confusion-limited map
of the GOODS-S field taken with AzTEC on the ASTE telescope. We imaged a 270
sq. arcmin field to a 1\sigma depth of 0.48 - 0.73 mJy/beam, making this one of
the deepest blank-field surveys at mm-wavelengths ever achieved. Although our
GOODS-S map is extremely confused, we demonstrate that our source
identification and number counts analyses are robust, and the techniques
discussed in this paper are relevant for other deeply confused surveys. We find
a total of 41 dusty starburst galaxies with S/N >= 3.5 within this uniformly
covered region, where only two are expected to be false detections. We derive
the 1.1mm number counts from this field using both a "P(d)" analysis and a
semi-Bayesian technique, and find that both methods give consistent results.
Our data are well-fit by a Schechter function model with (S', N(3mJy), \alpha)
= (1.30+0.19 mJy, 160+27 (mJy/deg^2)^(-1), -2.0). Given the depth of this
survey, we put the first tight constraints on the 1.1 mm number counts at
S(1.1mm) = 0.5 mJy, and we find evidence that the faint-end of the number
counts at S(850\mu m) < 2.0 mJy from various SCUBA surveys towards lensing
clusters are biased high. In contrast to the 870 \mu m survey of this field
with the LABOCA camera, we find no apparent under-density of sources compared
to previous surveys at 1.1 mm. Additionally, we find a significant number of
SMGs not identified in the LABOCA catalogue. We find that in contrast to
observations at wavelengths < 500 \mu m, MIPS 24 \mu m sources do not resolve
the total energy density in the cosmic infrared background at 1.1 mm,
demonstrating that a population of z > 3 dust-obscured galaxies that are
unaccounted for at these shorter wavelengths potentially contribute to a large
fraction (~2/3) of the infrared background at 1.1 mm.Comment: 21 pages, 9 figures. Accepted to MNRAS
Reinventing grounded theory: some questions about theory, ground and discovery
Grounded theoryâs popularity persists after three decades of broad-ranging critique. In this article three problematic notions are discussedââtheory,â âgroundâ and âdiscoveryââwhich linger in the continuing use and development of grounded theory procedures. It is argued that far from providing the epistemic security promised by grounded theory, these notionsâembodied in continuing reinventions of grounded theoryâconstrain and distort qualitative inquiry, and that what is contrived is not in fact theory in any meaningful sense, that âgroundâ is a misnomer when talking about interpretation and that what ultimately materializes following grounded theory procedures is less like discovery and more akin to invention. The procedures admittedly provide signposts for qualitative inquirers, but educational researchers should be wary, for the significance of interpretation, narrative and reflection can be undermined in the procedures of grounded theory
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