3,354 results on '"David Wilson"'
Search Results
52. A Systematic Review and Meta-Analysis of Efficacy of Botulinum Toxin A for Neuropathic Pain
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Anupam Datta Gupta, Suzanne Edwards, Jessica Smith, John Snow, Renuka Visvanathan, Graeme Tucker, and David Wilson
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neuropathic pain ,botulinum toxin ,systematic review ,meta-analysis ,Medicine - Abstract
We performed a systematic review and meta-analysis of randomised controlled trials (RCTs) conducted from January 2005 to June 2021 to update the evidence of Botulinum toxin A (BoNT-A) in neuropathic pain (NP) in addition to quality of life (QOL), mental health, and sleep outcomes. We conducted a Cochrane Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria analysis of RCTs from the following data sources: EMBASE, CINAHL, WHO International Clinical Trial Registry Platform, ClinicalTrials.gov, Cochrane database, Cochrane Clinical Trial Register, Australia New Zealand Clinical Trials Registry, and EU Clinical Trials Register. Meta-analysis of 17 studies showed a mean final VAS reduction in pain in the intervention group of 2.59 units (95% confidence interval: 1.79, 3.38) greater than the mean for the placebo group. The overall mean difference for sleep, Hospital Anxiety and Depression Scale (HADS) anxiety, HADS depression, and QOL mental and physical sub-scales were, respectively, 1.10 (95% CI: −1.71, 3.90), 1.41 (95% CI: −0.61, 3.43), −0.16 (95% CI: −1.95, 1.63), 0.85 (95% CI: −1.85, 3.56), and −0.71 (95% CI: −3.39, 1.97), indicating no significance. BoNT-A is effective for NP; however, small-scale RCTs to date have been limited in evidence. The reasons for this are discussed, and methods for future RCTs are developed to establish BoNT-A as the first-line agent.
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- 2022
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53. Attaining Value from Private Investment in Power Generation Projects in Indonesia: An Empirical Study
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Gigih Atmo, Colin Duffield, and David Wilson
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ppp project finance structure ,value for money ,power plant ,public private partnerships ,General Works ,Social Sciences ,Technology - Abstract
Provision of electrical infrastructure in emerging economies, like Indonesia, is very challenging post the 2008 Global Financial Crisis (GFC). Constrained lending via international finance markets has led to a reduction in the number of investors and shorter lending periods for public private partnerships (PPPs) projects. While domestic Indonesian investors and banks have begun to be involved in such projects, the scale of budgetary requirements for the delivery of power plant projects generally exceeds the financial capacity of both the public sector and local financial markets. This paper presents the findings of a Delphi style survey and proposes implementation strategies that may overcome current investment constraints and still attain Value for Money (VfM) from the delivery of Indonesian PPP power projects post the 2008 GFC. Initially, qualitative data was acquired from two industry seminars to establish the context of Indonesian PPP power projects. This was followed by two rounds of the Delphi technique to develop consensus among a panel of industry experts about realizing VfM from Indonesian PPPs. The results show that (i) export credit agencies from regional Asian countries have increased their roles to support PPP power projects (ii) structural deficiencies of local power industry manufacturing has created barriers for greater roles of local finances in the projects (iii) enhanced contractual risk allocation between the public and private sector can potentially improve project outcomes; these involve greater transparency and accountability of project guarantee processes. This study adapted key implementation features for attaining VfM into short, medium, and long term development strategies that are suitable for Indonesia. It has been concluded that a sustainable energy system can be realized when there is alignment of interests between the government, project sponsors, fuel suppliers, and lenders.
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- 2018
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54. Using Complexity and Network Concepts to Inform Healthcare Knowledge Translation
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Alison Kitson, Alan Brook, Gill Harvey, Zoe Jordan, Rhianon Marshall, Rebekah O’Shea, and David Wilson
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Knowledge Translation (KT) ,Evidence-Based Practice ,Implementation Science ,Complex Adaptive Systems (CASs) ,Complexity ,Networks ,Integrated Knowledge Translation ,Public aspects of medicine ,RA1-1270 - Abstract
Many representations of the movement of healthcare knowledge through society exist, and multiple models for the translation of evidence into policy and practice have been articulated. Most are linear or cyclical and very few come close to reflecting the dense and intricate relationships, systems and politics of organizations and the processes required to enact sustainable improvements. We illustrate how using complexity and network concepts can better inform knowledge translation (KT) and argue that changing the way we think and talk about KT could enhance the creation and movement of knowledge throughout those systems needing to develop and utilise it. From our theoretical refinement, we propose that KT is a complex network composed of five interdependent sub-networks, or clusters, of key processes (problem identification [PI], knowledge creation [KC], knowledge synthesis [KS], implementation [I], and evaluation [E]) that interact dynamically in different ways at different times across one or more sectors (community; health; government; education; research for example). We call this the KT Complexity Network, defined as a network that optimises the effective, appropriate and timely creation and movement of knowledge to those who need it in order to improve what they do. Activation within and throughout any one of these processes and systems depends upon the agents promoting the change, successfully working across and between multiple systems and clusters. The case is presented for moving to a way of thinking about KT using complexity and network concepts. This extends the thinking that is developing around integrated KT approaches. There are a number of policy and practice implications that need to be considered in light of this shift in thinking.
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- 2018
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55. Declining prevalence of undiagnosed HIV in Melbourne: results from community‐based bio‐behavioural studies of gay and bisexual men
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Mark Stoové, Jason Asselin, Alisa Pedrana, Toby Lea, Margaret Hellard, David Wilson, Garrett Prestage, John de Wit, and Martin Holt
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undiagnosed HIV ,gay and bisexual men ,Australia ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Objective: To measure changes in undiagnosed HIV among gay and bisexual men (GBM) in Melbourne. Methods: Undiagnosed HIV was compared between GBM recruited anonymously in 2008 in gay venues only and GBM anonymously or confidentially (results delivery) recruited in 2014 at gay venues and a community festival. Surveys were completed and oral fluid specimens collected for HIV testing; positive tests among GBM reporting being HIV‐negative or unknown/untested were classified as undiagnosed. Tests of proportions compared serological prevalence, undiagnosed prevalence and participant characteristics. Results: HIV prevalence was 9.5% and 7.1% among 639 and 993 GBM recruited in 2008 and 2014, respectively; undiagnosed prevalence declined significantly from 31.1% to 7.1% (p
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- 2018
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56. A New RAM Normalized 1$f$-WMS Technique for the Measurement of Gas Parameters in Harsh Environments and a Comparison With ${2f\!/\!1f}$
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Abhishek Upadhyay, Michael Lengden, David Wilson, Gordon Samuel Humphries, Andrew P. Crayford, Daniel G. Pugh, Mark P. Johnson, George Stewart, and Walter Johnstone
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Wavelength modulation spectroscopy ,Calibration-free TDLS ,1 ${f}$ -WMS ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
A calibration-free first harmonic (1t ) wavelength modulation spectroscopy (1tWMS) technique for gas species parameter measurement is demonstrated. In this technique, the total magnitude of the 1t-WMS signal is normalized by a component of the 1t residual amplitude modulation signal. This method preserves the advantages of the traditional nt/1t - WMS (n ≥ 2) technique, such as the immunity to the non-absorbing systematic losses and the accurate recovery of gas parameters, without the requirement for non-absorbing regions for normalization at high pressure or high modulation index values (m-values). The proposed technique only requires the 1t signal, which has the largest magnitude of all the harmonics signals, and, therefore, fundamentally has a higher sensitivity to the nt/1t technique. Furthermore, since only the 1t-WMS signal is used, the technique is less complex in terms of signal processing and data acquisition. This paper also shows a comparison of the proposed technique and 2t/1t for measuring CO2 in the exhaust of a combuster. The data highlight how nonlinearities in the optical detection system as a function of frequency have a considerable effect on the recovered 2t/1t spectra, causing variation in the recovered gas concentrations. This effect is not seen in the methodology proposed in this paper.
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- 2018
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57. A systematic review: efficacy of botulinum toxin in walking and quality of life in post-stroke lower limb spasticity
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Anupam Datta Gupta, Wing Hong Chu, Stuart Howell, Subhojit Chakraborty, Simon Koblar, Renuka Visvanathan, Ian Cameron, and David Wilson
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Stroke ,Spasticity ,Botulinum toxin ,Lower limb ,Medicine - Abstract
Abstract Background Improved walking is one of the highest priorities in people living with stroke. Post-stroke lower limb spasticity (PSLLS) impedes walking and quality of life (QOL). The understanding of the evidence of improved walking and QOL following botulinum toxin (BoNTA) injection is not clear. We performed a systematic review of the randomized control trials (RCT) to evaluate the effectiveness of BoNTA injection on walking and QOL in PSLLS. Methods We searched PubMed, Web of Science, Embase, CINAHL, ProQuest Thesis and Dissertation checks, Google Scholar, WHO International Clinical Trial Registry Platform, ClinicalTrials.gov , Cochrane, and ANZ and EU Clinical Trials Register for RCTs looking at improvement in walking and QOL following injection of BoNTA in PSLLS. The original search was carried out prior to 16 September 2015. We conducted an additional verifying search on CINHAL, EMBASE, and MEDLINE (via PubMed) from 16 September 2015 to 6 June 2017 using the same clauses as the previous search. Methodological quality of the individual studies was critically appraised using Joanna Briggs Institute’s instrument. Only placebo-controlled RCTs looking at improvement in walking and QOL were included in the review. Results Of 2026 records, we found 107 full-text records. Amongst them, we found five RCTs qualifying our criteria. No new trials were found from the verifying search. Two independent reviewers assessed methodological validity prior to inclusion in the review using Joanna Briggs Institute’s appraisal instrument. Two studies reported significant improvement in gait velocity (p = 0.020) and
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- 2018
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58. Critical Success Factors in Thailand′s Green Building Industry
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Wenxin Shen, Wenzhe Tang, Atthaset Siripanan, Zhen Lei, Colin F. Duffield, David Wilson, Felix Kin Peng Hui, and Yongping Wei
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green building ,success factors ,leadership in energy and environmental design (leed) ,thailand′s rating of energy and environmental sustainability (trees) ,Architecture ,NA1-9428 ,Building construction ,TH1-9745 - Abstract
The promotion of Green Buildings (GB) has become a global trend that improves resource efficiency and the well-being of societies. The development of GB still encounters different obstacles in developing countries. The critical success factors of GB and their relationships with GB certification levels in Thailand have been investigated. The relationships between the competence of individual project participants and competence of project team at different GB certification levels are also analyzed. The results reveal the underlying patterns of the overall picture of the GB industry in Thailand, and suggest that all project participants should continuously improve their competences via technical and management innovation for delivering affordable and sustainable products, thereby making green buildings more available and appealing to the public. This study provides empirical evidence for all project participants to adopt appropriate team building strategies and optimally allocate their resources to achieve the suitable GB certification levels.
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- 2017
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59. Calibration-Free WMS Using a cw-DFB-QCL, a VCSEL, and an Edge-Emitting DFB Laser With In-Situ Real-Time Laser Parameter Characterization
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Abhishek Upadhyay, David Wilson, Michael Lengden, Arup L. Chakraborty, George Stewart, and Walter Johnstone
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Calibration-free gas measurement ,absorption spectroscopy ,wavelength modulation spectroscopy ,tunable diode laser absorption spectroscopy (TDLAS) ,continuous wave distributed feedback quantum cascade laser (cw-DFB-QCL). ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
This paper presents a detailed experimental wavelength modulation spectroscopy approach and demonstrates its applicability to various types of semiconductor lasers in the near infrared and mid-infrared. A 5250 nm continuous-wave distributed feedback quantum cascade laser, a 2004 nm vertical cavity surface emitting laser, and a 1650 nm distributed feedback edge-emitting laser are used to extract the concentration and pressure values of nitric oxide, carbon dioxide, and methane, respectively, using the 2f wavelength modulation spectroscopy (WMS) technique under controlled conditions. The generality of the technique is demonstrated by extending it to 3f WMS for the three different kinds of lasers used in this study. The methodology required to provide in-situ real-time measurements of both gas parameters and operating characteristics of the laser are described in detail. Finally, the advantages and limitations of the technique are discussed in view of the fact that the characteristic behavior of the laser sources is significantly different. We specifically discuss the issue of targeting non-absorbing wavelength regions and the choice of modulation frequency and modulation amplitude of the laser, as well as the choice of the detection harmonic.
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- 2017
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60. The Knowledge Translation Complexity Network (KTCN) Model: The Whole Is Greater Than the Sum of the Parts - A Response to Recent Commentaries
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Alison Kitson, Rebekah O’Shea, Alan Brook, Gill Harvey, Zoe Jordan, Rhianon Marshall, and David Wilson
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Knowledge Translation (KT) ,Implementation Science ,Complex Adaptive Systems (CASs) ,Complexity ,Networks ,Integrated Knowledge Translation ,Public aspects of medicine ,RA1-1270 - Published
- 2018
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61. Adherence clubs and decentralized medication delivery to support patient retention and sustained viral suppression in care: Results from a cluster-randomized evaluation of differentiated ART delivery models in South Africa.
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Matthew P Fox, Sophie Pascoe, Amy N Huber, Joshua Murphy, Mokgadi Phokojoe, Marelize Gorgens, Sydney Rosen, David Wilson, Yogan Pillay, and Nicole Fraser-Hurt
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Medicine - Abstract
BackgroundDifferentiated antiretroviral therapy (ART) delivery models, in which patients are provided with care relevant to their current status (e.g., newly initiating, stable on treatment, or unstable on treatment) has become an essential part of patient-centered health systems. In 2015, the South African government implemented Chronic Disease Adherence Guidelines (AGLs), which involved five interventions: Fast Track Initiation Counseling for newly initiating patients, Enhanced Adherence Counseling for patients with an unsuppressed viral load, Early Tracing of patients who miss visits, and Adherence Clubs (ACs) and Decentralized Medication Delivery (DMD) for stable patients. We evaluated two of these interventions in 24 South African facilities: ACs, in which patients meet in groups outside usual clinic procedures and receive medication; and DMD, in which patients pick up their medication outside usual pharmacy queues.Methods and findingsWe compared those participating in ACs or receiving DMD at intervention sites to those eligible for ACs or DMD at control sites. Outcomes were retention and sustained viral suppression (ConclusionsIn this study, we found comparable DMD outcomes versus standard of care at facilities, a benefit for retention of patients in care with ACs, and apparent benefits in terms of retention (for AC patients) and sustained viral suppression (for DMD patients) among men. This suggests the importance of alternative service delivery models for men and of community-based strategies to decongest primary healthcare facilities. Because these strategies also reduce patient inconvenience and decongest clinics, comparable outcomes are a potential success. The cost of all five AGL interventions and possible effects on reducing clinic congestion should be investigated.Clinical trial registrationNCT02536768.
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- 2019
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62. Reactive Transport of Manure-Derived Nitrogen in the Vadose Zone: Consideration of Macropore Connectivity to Subsurface Receptors
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Syed I. Hussain, Steven K. Frey, David W. Blowes, Carol J. Ptacek, David Wilson, K. Ulrich Mayer, Danyang Su, Natalie Gottschall, Mark Edwards, and David R. Lapen
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Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Macropores can be important conduits for surface-derived nutrients to reach subsurface receptors. Accordingly, nutrient reactive transport processes in macroporous soils need to be well understood. In this study, steady-state two-dimensional reactive transport simulations with MIN3P-THCm (version 1.0.519.0) were used to elucidate how soil macropore connectivity to tile drains can influence N transformations following liquid swine manure (LSM) applications to soil. Four different soil scenarios were considered: homogeneous sand, homogeneous clay loam, and clay loam with discrete macropores connected to or disconnected from the bottom boundary used to represent tile drain outflow. In relation to the homogeneous soils, macropores, overall, facilitated chemical diffusion into the adjacent soil matrix along their length and broadly augmented O ingress into the soil profile. These processes combined to critically control the spatial distribution of NH oxidation reaction products. When used in transient simulation mode with field data observed at experimental tile-drained plots that received LSM application, the model showed that simulated nitrate mass losses to tile are considerably higher and most realistic under the connected macropore scenario compared with the homogeneous or disconnected macropore scenarios.
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- 2019
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63. A C-Terminal Fragment of Chlorotoxin Retains Bioactivity and Inhibits Cell Migration
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Mohadeseh Dastpeyman, Paul Giacomin, David Wilson, Matthew J. Nolan, Paramjit S. Bansal, and Norelle L. Daly
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chlorotoxin ,tumor-imaging agent ,metastasis ,migration ,invasion ,disulfide-rich peptide ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Chlorotoxin was originally isolated from the venom of the Israeli scorpion Leiurus quinquestriatus, and has potential as a tumor imaging agent based on its selective binding to tumor cells. Several targets have been suggested for chlorotoxin including voltage-gated chloride channels, and it has been shown to have anti-angiogenic activity and inhibit cell migration. The structure of chlorotoxin is stabilized by four disulfide bonds and contains β-sheet and helical structure. Interestingly, the reduced form has previously been shown to inhibit cell migration to the same extent as the wild type, but structural analysis indicates that the reduced form of the peptide does not maintain the native secondary structure and appears unstructured in solution. This lack of structure suggests that a short stretch of amino acids might be responsible for the bioactivity. To explore this hypothesis, we have synthesized fragments of chlorotoxin without disulfide bonds. As expected for such small peptides, NMR analysis indicated that the peptides were unstructured in solution. However, the peptide corresponding to the eight C-terminal residues inhibited cell migration, in contrast to the other fragments. Our results suggest that the C-terminal region plays a critical role in the bioactivity of chlorotoxin.
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- 2019
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64. Effect of changes in tidal volume on multiple breath washout outcomes.
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Felix Ratjen, Renee Jensen, Michelle Klingel, Reginald McDonald, Courtney Moore, Nick Benseler, David Wilson, and Sanja Stanojevic
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Medicine ,Science - Abstract
The lung clearance index (LCI), measured by multiple breath washout (MBW), reflects global ventilation inhomogeneity and is a sensitive marker of early obstructive airway disease. For the MBW test to accurately reflect a subject's gas mixing within the lungs, the breathing pattern should represent physiologically appropriate tidal volumes (VT) and respiratory rate (RR). We aimed to assess whether changes in VT impact MBW outcome measures with a series of prospective and retrospective studies. MBW testing was performed using the Exhalyzer ® D (EcoMedics AG, Switzerland). Healthy adult subjects performed MBW with uninstructed tidal breathing and a series of instructed tidal breathing tests, designed to isolate specific features of the breathing pattern. In addition, we retrospectively analyzed MBW data from two pediatric multi-centre interventional studies of cystic fibrosis (CF) subjects to determine the range of VT observed during uninstructed breathing, and whether breathing outside this range impacted results. The LCI was lower, but not significantly different between deep breathing at 20 ml/kg body weight and uninstructed tidal breathing; whereas LCI was significantly higher during shallow breathing compared with normal tidal breathing. For the majority of subjects with CF (80%), VT ranged from 9-15mL/kg. Within the observed VT range, LCI was similar in trials with mean VT /kg below this range compared to trials with VT /kg within the range. If subjects breathe naturally and are not instructed to use specific targets, the range of VT is within physiologically appropriate limits and normal variations observed do not impact MBW outcomes.
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- 2019
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65. Using registry data to characterize the incidence and causes of blindness in Oregon.
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Mitchell V Brinks, Travis Redd, William E Lambert, Tosha Zaback, Joan Randall, Teresa Field, and David Wilson
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Medicine ,Science - Abstract
In the United States, there is no reliable data to describe the prevalence of eye diseases leading to visual impairment and little active surveillance to address this knowledge gap. Data that is readily available from many state blind registries may provide helpful information on trends and causes of blindness. We analyzed new registrations with the Oregon Commission for the Blind (OCB) and Oregon State Department of Administrative Services (DAS) from 1961 to 2016 for causes of and trends in blindness. Persons with blindness self-refer into the OCB registry and the Oregon State Department of Administrative Services (DAS) includes those receiving social security disability financial support and other state services. Data for 9,273 blind persons registered were analyzed. The most frequent causes of blindness were age related macular degeneration (AMD) 3,308 (38%), followed by diabetic retinopathy (DR) 729 (8%), congenital conditions 697 (8%), optic nerve atrophy 611 (7%), glaucoma 549 (6%), retinitis pigmentosa 546 (6%), retinopathy of prematurity192 (2%), cataract 180 (2%), and trauma 174 (2%). The mean age of onset of blindness was younger for Blacks (31 years) and Hispanics (33 years) than for Whites (44 years). Analysis of state-based registries can provide useful and locally relevant vision and eye health data where little information is otherwise available.
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- 2019
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66. Incentives for Bushmeat Consumption and Importation among West African Immigrants, Minnesota, USA
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Emily Walz, David Wilson, Jacob C. Stauffer, Danushka Wanduragala, William M. Stauffer, Dominic A. Travis, and Jonathan D. Alpern
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Global health ,animals, wild ,emigrants, immigrants, zoonoses, public health, West Africa, Liberia, Minneapolis, Saint Paul, Minnesota, travel medicine, hemorrhagic fever, Ebola, f ,wild animals ,emigrants ,immigrants ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
The knowledge, attitudes, and practices surrounding bushmeat consumption and importation in the United States are not well described. Focus groups of West African persons living in Minnesota, USA, found that perceived risks are low and unlikely to deter consumers. Incentives for importation and consumption were multifactorial in this community.
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- 2017
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67. Effects of Targeting Reading Interventions: Testing a Skill-by-Treatment Interaction in an Applied Setting
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Matthew Burns, McKinzie Duesenberg-Marshall, Katya Sussman-Dawson, Monica Romero, David Wilson, and Melinda Felten
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The current study compared the reading growth of (a) students who received targeted interventions, (b) students who received typical school interventions, and (c) students who were proficient readers at the study's onset. The participants were 1,513 students in first through fifth grades who attended one of three treatment schools or one of three control schools. Students who received a targeted intervention had higher adjusted mean growth scores from fall to winter than students who received the typical school intervention, after controlling for grade and free or reduced-price lunch status, but had relatively equal mean growth score as the proficient readers. The data supported previous research but found positive effects for interventions that were selected and implemented by school personnel in an applied setting.
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- 2024
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68. Folding of Truncated Granulin Peptides
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Rozita Takjoo, David Wilson, Paramjit S. Bansal, Alex Loukas, Michael J. Smout, and Norelle L. Daly
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granulins ,peptide ,oxidative folding ,NMR spectroscopy ,cell proliferation ,Microbiology ,QR1-502 - Abstract
Granulins are a family of unique protein growth factors which are found in a range of species and have several bioactivities that include cell proliferation and wound healing. They typically contain six disulfide bonds, but the sequences, structures and bioactivities vary significantly. We have previously shown that an N-terminally truncated version of a granulin from the human liver fluke, Opisthorchis viverrini, can fold independently into a “mini-granulin” structure and has potent wound healing properties in vivo. The incorporation of a non-native third disulfide bond, with respect to the full-length granulin module, was critical for the formation of regular secondary structure in the liver fluke derived peptide. By contrast, this third disulfide bond is not required for a carp granulin-1 truncated peptide to fold independently. This distinction led us to explore granulins from the zebrafish model organism. Here we show that the mini-granulin fold occurs in a naturally occurring paragranulin (half-domain) from zebrafish, and is also present in a truncated form of a full-length zebrafish granulin, suggesting this structure might be a common property in either naturally occurring or engineered N-terminally truncated granulins and the carp granulin-1 folding is an anomaly. The in vitro folding yield is significantly higher in the naturally occurring paragranulin, but only the truncated zebrafish granulin peptide promoted the proliferation of fibroblasts consistent with a growth factor function, and therefore the function of the paragranulin remains unknown. These findings provide insight into the folding and evolution of granulin domains and might be useful in the elucidation of the structural features important for bioactivity to aid the design of more potent and stable analogues for the development of novel wound healing agents.
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- 2020
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69. Australian Scorpion Hormurus waigiensis Venom Fractions Show Broad Bioactivity through Modulation of Bio-Impedance and Cytosolic Calcium
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David M. Housley, Jeremy L. Pinyon, Georg von Jonquieres, Chamini J. Perera, Michael Smout, Michael J. Liddell, Ernest A. Jennings, David Wilson, and Gary D. Housley
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membrane biophysics ,scorpion toxins ,xCELLigence Real Time Cell Analysis ,GCaMP5G calcium reporter ,ryanodine receptors ,calcium store ,Microbiology ,QR1-502 - Abstract
Scorpion venoms are a rich source of bioactive molecules, but characterisation of toxin peptides affecting cytosolic Ca2+, central to cell signalling and cell death, is limited. We undertook a functional screening of the venom of the Australian scorpion Hormurus waigiensis to determine the breadth of Ca2+ mobilisation. A human embryonic kidney (HEK293) cell line stably expressing the genetically encoded Ca2+ reporter GCaMP5G and the rabbit type 1 ryanodine receptor (RyR1) was developed as a biosensor. Size-exclusion Fast Protein Liquid Chromatography separated the venom into 53 fractions, constituting 12 chromatographic peaks. Liquid chromatography mass spectroscopy identified 182 distinct molecules with 3 to 63 components per peak. The molecular weights varied from 258 Da—13.6 kDa, with 53% under 1 kDa. The majority of the venom chromatographic peaks (tested as six venom pools) were found to reversibly modulate cell monolayer bioimpedance, detected using the xCELLigence platform (ACEA Biosciences). Confocal Ca2+ imaging showed 9/14 peak samples, with molecules spanning the molecular size range, increased cytosolic Ca2+ mobilization. H. waigiensis venom Ca2+ activity was correlated with changes in bio-impedance, reflecting multi-modal toxin actions on cell physiology across the venom proteome.
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- 2020
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70. Synthesis, Pharmacological and Structural Characterization of Novel Conopressins from Conus miliaris
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Julien Giribaldi, Lotten Ragnarsson, Tom Pujante, Christine Enjalbal, David Wilson, Norelle L. Daly, Richard J. Lewis, and Sebastien Dutertre
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conopressin ,vasopressin ,venom ,cone snail ,conotoxin ,Biology (General) ,QH301-705.5 - Abstract
Cone snails produce a fast-acting and often paralyzing venom, largely dominated by disulfide-rich conotoxins targeting ion channels. Although disulfide-poor conopeptides are usually minor components of cone snail venoms, their ability to target key membrane receptors such as GPCRs make them highly valuable as drug lead compounds. From the venom gland transcriptome of Conus miliaris, we report here on the discovery and characterization of two conopressins, which are nonapeptide ligands of the vasopressin/oxytocin receptor family. These novel sequence variants show unusual features, including a charge inversion at the critical position 8, with an aspartate instead of a highly conserved lysine or arginine residue. Both the amidated and acid C-terminal analogues were synthesized, followed by pharmacological characterization on human and zebrafish receptors and structural investigation by NMR. Whereas conopressin-M1 showed weak and only partial agonist activity at hV1bR (amidated form only) and ZFV1a1R (both amidated and acid form), both conopressin-M2 analogues acted as full agonists at the ZFV2 receptor with low micromolar affinity. Together with the NMR structures of amidated conopressins-M1, -M2 and -G, this study provides novel structure-activity relationship information that may help in the design of more selective ligands.
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- 2020
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71. Prognostic models for identifying risk of poor outcome in people with acute ankle sprains: the SPRAINED development and external validation study
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David J Keene, Michael M Schlüssel, Jacqueline Thompson, Daryl A Hagan, Mark A Williams, Christopher Byrne, Steve Goodacre, Matthew Cooke, Stephen Gwilym, Philip Hormbrey, Jennifer Bostock, Kirstie Haywood, David Wilson, Gary S Collins, and Sarah E Lamb
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ankle ,sprain ,injury ,prognosis ,systematic review ,nominal group technique ,observational cohort ,prognostic model ,Medical technology ,R855-855.5 - Abstract
Background: Ankle sprains are very common injuries. Although recovery can occur within weeks, around one-third of patients have longer-term problems. Objectives: To develop and externally validate a prognostic model for identifying people at increased risk of poor outcome after an acute ankle sprain. Design: Development of a prognostic model in a clinical trial cohort data set and external validation in a prospective cohort study. Setting: Emergency departments (EDs) in the UK. Participants: Adults with an acute ankle sprain (within 7 days of injury). Sample size: There were 584 clinical trial participants in the development data set and 682 recruited for the external validation study. Predictors: Candidate predictor variables were chosen based on availability in the clinical data set, clinical consensus, face validity, a systematic review of the literature, data quality and plausibility of predictiveness of the outcomes. Main outcome measures: Models were developed to predict two composite outcomes representing poor outcome. Outcome 1 was the presence of at least one of the following symptoms at 9 months after injury: persistent pain, functional difficulty or lack of confidence. Outcome 2 included the same symptoms as outcome 1, with the addition of recurrence of injury. Rates of poor outcome in the external data set were lower than in the development data set, 7% versus 20% for outcome 1 and 16% versus 24% for outcome 2. Analysis: Multiple imputation was used to handle missing data. Logistic regression models, together with multivariable fractional polynomials, were used to select variables and identify transformations of continuous predictors that best predicted the outcome based on a nominal alpha of 0.157, chosen to minimise overfitting. Predictive accuracy was evaluated by assessing model discrimination (c-statistic) and calibration (flexible calibration plot). Results: (1) Performance of the prognostic models in development data set – the combined c-statistic for the outcome 1 model across the 50 imputed data sets was 0.74 [95% confidence interval (CI) 0.70 to 0.79], with good model calibration across the imputed data sets. The combined c-statistic for the outcome 2 model across the 50 imputed data sets was 0.70 (95% CI 0.65 to 0.74), with good model calibration across the imputed data sets. Updating these models, which used baseline data collected at the ED, with an additional variable at 4 weeks post injury (pain when bearing weight on the ankle) improved the discriminatory ability (c-statistic 0.77, 95% CI 0.73 to 0.82, for outcome 1 and 0.75, 95% CI 0.71 to 0.80, for outcome 2) and calibration of both models. (2) Performance of the models in the external data set – the combined c-statistic for the outcome 1 model across the 50 imputed data sets was 0.73 (95% CI 0.66 to 0.79), with a calibration plot intercept of –0.91 (95% CI –0.98 to 0.44) and slope of 1.13 (95% CI 0.76 to 1.50). The combined c-statistic for the outcome 2 model across the 50 imputed data sets was 0.63 (95% CI 0.58 to 0.69), with a calibration plot intercept of –0.25 (95% CI –0.27 to 0.11) and slope of 1.03 (95% CI 0.65 to 1.42). The updated models with the additional pain variable at 4 weeks had improved discriminatory ability over the baseline models but not better calibration. Conclusions: The SPRAINED (Synthesising a clinical Prognostic Rule for Ankle Injuries in the Emergency Department) prognostic models performed reasonably well, and showed benefit compared with not using any model; therefore, the models may assist clinical decision-making when managing and advising ankle sprain patients in the ED setting. The models use predictors that are simple to obtain. Limitations: The data used were from a randomised controlled trial and so were not originally intended to fulfil the aim of developing prognostic models. However, the data set was the best available, including data on the symptoms and clinical events of interest. Future work: Further model refinement, including recalibration or identifying additional predictors, may be required. The effect of implementing and using either model in clinical practice, in terms of acceptability and uptake by clinicians and on patient outcomes, should be investigated. Trial registration: Current Controlled Trials ISRCTN12726986. Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 64. See the NIHR Journals Library website for further project information. Funding was also recieved from the NIHR Collaboration for Leadership in Applied Health Research, Care Oxford at Oxford Health NHS Foundation Trust, NIHR Biomedical Research Centre, Oxford, and the NIHR Fellowship programme.
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- 2018
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72. Protocol for an HIV Pre-exposure Prophylaxis (PrEP) Population Level Intervention Study in Victoria Australia: The PrEPX Study
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Kathleen E. Ryan, Anne Mak, Mark Stoove, Brian Price, Christopher K. Fairley, Simon Ruth, Luxshimi Lal, Jason Asselin, Carol El-Hayek, Long Nguyen, Colin Batrouney, David Wilson, John Lockwood, Dean Murphy, Vincent J. Cornelisse, Norman Roth, Jeff Willcox, Christina C. Chang, Judy Armishaw, Ban K. Tee, Matthew Penn, George Forgan-Smith, Christopher Williams, Jeff Montgomery, Kat Byron, Alison Coelho, Brent Allen, Jeremy Wiggins, Jenny Kelsall, Olga Vujovic, Michael West, Anna B. Pierce, Daniel Gallant, Charlotte Bell, John B. F. de Wit, Jennifer F. Hoy, Steve L. Wesselingh, Robert M. Grant, and Edwina J. Wright
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PrEP ,HIV ,MSM ,prevention ,protocol ,Public aspects of medicine ,RA1-1270 - Abstract
Background: Pre-exposure prophylaxis (PrEP) is the use of HIV anti-retroviral therapy to prevent HIV transmission in people at high risk of HIV acquisition. PrEP is highly efficacious when taken either daily, or in an on-demand schedule. In Australia co-formulated tenofovir-emtricitabine is registered for daily use for PrEP, however, this co-formulation is not listed yet on the national subsidized medicines list. We describe a study protocol that aims to demonstrate if the provision of PrEP to up to 3800 individuals at risk of HIV in Victoria, Australia reduces HIV incidence locally by 25% generally and 30% among GBM.Methods: PrEPX is a population level intervention study in Victoria, Australia in which generic PrEP will be delivered to 3800 individuals for up to 36 months. Study eligibility is consistent with the recently updated 2017 Australian PrEP guidelines. Participants will attend study clinics, shared care clinics, or outreach clinics for quarterly HIV/STI screening, biannual renal function tests and other clinical care as required. Study visits and STI diagnoses will be recorded electronically through the ACCESS surveillance system. At each study visit participants will be invited to complete behavioral surveys that collect demographics and sexual risk data. Diagnosis and behavioral data will be compared between PrEPX participants and other individuals testing within the ACCESS surveillance system. A subset of participants will complete in depth surveys and interviews to collect attitudes, beliefs and acceptability data. Participating clinics will provide clinic level data on implementation and management of PrEPX participants. The population level impact on HIV incidence will be assessed using Victorian HIV notification data.Discussion: This study will collect evidence on the real world impact of delivery of PrEP to 3800 individuals at risk of acquiring HIV in Victoria. This study will provide important information for the broader implementation of PrEP planning upon listing of the tenofovir-emtricitabine on the national subsidized list of medicines. The study is registered on the Australian New Zealand Clinical Trials Registry (ACTRN12616001215415)
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- 2018
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73. The KnownLeaf literature curation system captures knowledge about Arabidopsis leaf growth and development and facilitates integrated data mining
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Dóra Szakonyi, Sofie Van Landeghem, Katja Baerenfaller, Lieven Baeyens, Jonas Blomme, Rubén Casanova-Sáez, Stefanie De Bodt, David Esteve-Bruna, Fabio Fiorani, Nathalie Gonzalez, Jesper Grønlund, Richard G.H. Immink, Sara Jover-Gil, Asuka Kuwabara, Tamara Muñoz-Nortes, Aalt D.J. van Dijk, David Wilson-Sánchez, Vicky Buchanan-Wollaston, Gerco C. Angenent, Yves Van de Peer, Dirk Inzé, José Luis Micol, Wilhelm Gruissem, Sean Walsh, and Pierre Hilson
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Arabidopsis ,Leaf growth ,Literature curation ,Data integration ,Botany ,QK1-989 - Abstract
The information that connects genotypes and phenotypes is essentially embedded in research articles written in natural language. To facilitate access to this knowledge, we constructed a framework for the curation of the scientific literature studying the molecular mechanisms that control leaf growth and development in Arabidopsis thaliana (Arabidopsis). Standard structured statements, called relations, were designed to capture diverse data types, including phenotypes and gene expression linked to genotype description, growth conditions, genetic and molecular interactions, and details about molecular entities. Relations were then annotated from the literature, defining the relevant terms according to standard biomedical ontologies. This curation process was supported by a dedicated graphical user interface, called Leaf Knowtator. A total of 283 primary research articles were curated by a community of annotators, yielding 9947 relations monitored for consistency and over 12,500 references to Arabidopsis genes. This information was converted into a relational database (KnownLeaf) and merged with other public Arabidopsis resources relative to transcriptional networks, protein–protein interaction, gene co-expression, and additional molecular annotations. Within KnownLeaf, leaf phenotype data can be searched together with molecular data originating either from this curation initiative or from external public resources. Finally, we built a network (LeafNet) with a portion of the KnownLeaf database content to graphically represent the leaf phenotype relations in a molecular context, offering an intuitive starting point for knowledge mining. Literature curation efforts such as ours provide high quality structured information accessible to computational analysis, and thereby to a wide range of applications. DATA: The presented work was performed in the framework of the AGRON-OMICS project (Arabidopsis GRO wth Network integrating OMICS technologies) supported by European Commission 6th Framework Programme project (Grant number LSHG-CT-2006-037704). This is a data integration and data sharing portal collecting all the all the major results from the consortium. All data presented in our paper is available here. https://agronomics.ethz.ch/.
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- 2015
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74. Relapse to opioid use in opioid-dependent individuals released from compulsory drug detention centres compared with those from voluntary methadone treatment centres in Malaysia: a two-arm, prospective observational study
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Martin P Wegman, BSc, Prof. Frederick L Altice, MD, Sangeeth Kaur, MBBS, Vanesa Rajandaran, MPP, Sutayut Osornprasop, PhD, David Wilson, PhD, Prof. David P Wilson, PhD, and Adeeba Kamarulzaman, FRACP
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Public aspects of medicine ,RA1-1270 - Abstract
Background: Detention of people who use drugs into compulsory drug detention centres (CDDCs) is common throughout East and Southeast Asia. Evidence-based pharmacological therapies for treating substance use disorders, such as opioid agonist treatments with methadone, are generally unavailable in these settings. We used a unique opportunity where CDDCs coexisted with voluntary drug treatment centres (VTCs) providing methadone in Malaysia to compare the timing and occurrence of opioid relapse (measured using urine drug testing) in individuals transitioning from CDDCs versus methadone maintenance in VTCs. Methods: We did a parallel, two-arm, prospective observational study of opioid-dependent individuals aged 18 years and older who were treated in Malaysia in the Klang Valley in two settings: CDDCs and VTCs. We used sequential sampling to recruit individuals. Assessed individuals in CDDCs were required to participate in services such as counselling sessions and manual labour. Assessed individuals in VTCs could voluntarily access many of the components available in CDDCs, in addition to methadone therapy. We undertook urinary drug tests and behavioural interviews to assess individuals at baseline and at 1, 3, 6, 9, and 12 months post-release. The primary outcome was time to opioid relapse post-release in the community confirmed by urinary drug testing in individuals who had undergone baseline interviewing and at least one urine drug test (our analytic sample). Relapse rates between the groups were compared using time-to-event methods. This study is registered at ClinicalTrials.gov (NCT02698098). Findings: Between July 17, 2012, and August 21, 2014, we screened 168 CDDC attendees and 113 VTC inpatients; of these, 89 from CDDCs and 95 from VTCs were included in our analytic sample. The baseline characteristics of the two groups were similar. In unadjusted analyses, CDDC participants had significantly more rapid relapse to opioid use post-release compared with VTC participants (median time to relapse 31 days [IQR 26–32] vs 352 days [256–unestimable], log rank test, p
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- 2017
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75. A High-Level Synthesis Scheduling and Binding Heuristic for FPGA Fault Tolerance
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David Wilson, Aniruddha Shastri, and Greg Stitt
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Computer engineering. Computer hardware ,TK7885-7895 - Abstract
Computing systems with field-programmable gate arrays (FPGAs) often achieve fault tolerance in high-energy radiation environments via triple-modular redundancy (TMR) and configuration scrubbing. Although effective, TMR suffers from a 3x area overhead, which can be prohibitive for many embedded usage scenarios. Furthermore, this overhead is often worsened because TMR often has to be applied to existing register-transfer-level (RTL) code that designers created without considering the triplicated resource requirements. Although a designer could redesign the RTL code to reduce resources, modifying RTL schedules and resource allocations is a time-consuming and error-prone process. In this paper, we present a more transparent high-level synthesis approach that uses scheduling and binding to provide attractive tradeoffs between area, performance, and redundancy, while focusing on FPGA implementation considerations, such as resource realization costs, to produce more efficient architectures. Compared to TMR applied to existing RTL, our approach shows resource savings up to 80% with average resource savings of 34% and an average clock degradation of 6%. Compared to the previous approach, our approach shows resource savings up to 74% with average resource savings of 19% and an average heuristic execution time improvement of 96x.
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- 2017
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76. Feasibility of using a hand-held device to characterize tendon tissue biomechanics.
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Sahand Sohirad, David Wilson, Charlotte Waugh, Evan Finnamore, and Alexander Scott
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Medicine ,Science - Abstract
To examine the feasibility of using the MyotonPRO digital palpation device in measuring the transverse stiffness of tendon tissue.Experimental study.The MyotonPRO was used to measure the stiffness and related properties of ballistics gel in comparison with an external materials testing system (PCB electronics). The device was then used to measure the same properties of avian Achilles tendons before and after the removal of the overlying skin and subcutaneous tissue. Next, the test-retest reliability of the Achilles and patellar tendons was determined in humans. Finally, the stiffness of the Achilles tendon was measured before and after competitive running races of varying distances (10, 21 and 42 km, total number of athletes analyzed = 66).The MyotonPRO demonstrated a high degree of consistency when testing ballistics gel with known viscoelastic properties. The presence of skin overlying the avian Achilles tendon had a statistically significant impact on stiffness (p
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- 2017
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77. A Hamiltonian Surface-Shaping Approach for Control System Analysis and the Design of Nonlinear Wave Energy Converters
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Shadi Darani, Ossama Abdelkhalik, Rush D. Robinett, and David Wilson
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wave energy conversion ,nonlinear control ,Hamiltonian surface shaping ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
The dynamic model of Wave Energy Converters (WECs) may have nonlinearities due to several reasons such as a nonuniform buoy shape and/or nonlinear power takeoff units. This paper presents the Hamiltonian Surface-Shaping (HSS) approach as a tool for the analysis and design of nonlinear control of WECs. The Hamiltonian represents the stored energy in the system and can be constructed as a function of the WEC’s system states, its position, and velocity. The Hamiltonian surface is defined by the energy storage, while the system trajectories are constrained to this surface and determined by the power flows of the applied non-conservative forces. The HSS approach presented in this paper can be used as a tool for the design of nonlinear control systems that are guaranteed to be stable. The optimality of the obtained solutions is not addressed in this paper. The case studies presented here cover regular and irregular waves and demonstrate that a nonlinear control system can result in a multiple fold increase in the harvested energy.
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- 2019
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78. Ultrasound-Guided Portal Placement for Hip Arthroscopy
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Tanya Keough, M.D., David Wilson, M.D., M.A.Sc., and Ivan Wong, M.D., F.R.C.S.C.
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Orthopedic surgery ,RD701-811 - Abstract
Over the past 2 decades, hip arthroscopy has developed as a surgical technique, with more orthopaedic surgeons attempting to become proficient in performing this surgical procedure as indications and surgical skills evolve. The hip joint presents unique arthroscopic challenges because of its anatomic location, and it can be challenging to safely and confidently establish portal sites. Ultrasound-guided hip arthroscopy portal placement is not yet common practice for orthopaedic surgeons. The potential advantages of ultrasound-guided hip arthroscopy portal placement are the lack of radiation exposure to the patient and operating room personnel, direct visualization of the hip joint and surrounding soft-tissue structures, and lack of bulky fluoroscopic equipment in the operative field. We describe a detailed technique incorporating video examples using ultrasound guidance to establish appropriate portal sites for hip arthroscopy with the aim to improve safety and overall operator competence.
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- 2016
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79. Building from the HIV Response toward Universal Health Coverage.
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Jonathan Jay, Kent Buse, Marielle Hart, David Wilson, Robert Marten, Scott Kellerman, Morolake Odetoyinbo, Jonathan D Quick, Timothy Evans, Peter Piot, Mark Dybul, and Agnes Binagwaho
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Medicine - Abstract
Jonathan Jay and colleagues draw lessons from the the global HIV response that could help guide the universal health coverage movement.
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- 2016
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80. SharedNeRF: Leveraging Photorealistic and View-dependent Rendering for Real-time and Remote Collaboration.
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Mose Sakashita, Balasaravanan Thoravi Kumaravel, Nicolai Marquardt, and Andrew David Wilson
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- 2024
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81. Engineering of an Anti-Inflammatory Peptide Based on the Disulfide-Rich Linaclotide Scaffold
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Claudia Cobos, Paramjit S. Bansal, Linda Jones, Phurpa Wangchuk, David Wilson, Alex Loukas, and Norelle L. Daly
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anti-inflammatory peptides ,disulfide-rich peptides ,inflammatory bowel disease ,Biology (General) ,QH301-705.5 - Abstract
Inflammatory bowel diseases are a set of complex and debilitating diseases, for which there is no satisfactory treatment. Peptides as small as three amino acids have been shown to have anti-inflammatory activity in mouse models of colitis, but they are likely to be unstable, limiting their development as drug leads. Here, we have grafted a tripeptide from the annexin A1 protein into linaclotide, a 14-amino-acid peptide with three disulfide bonds, which is currently in clinical use for patients with chronic constipation or irritable bowel syndrome. This engineered disulfide-rich peptide maintained the overall fold of the original synthetic guanylate cyclase C agonist peptide, and reduced inflammation in a mouse model of acute colitis. This is the first study to show that this disulfide-rich peptide can be used as a scaffold to confer a new bioactivity.
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- 2018
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82. Nuclear Magnetic Resonance seq (NMRseq): A New Approach to Peptide Sequence Tags
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David Wilson and Norelle L. Daly
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NMR spectroscopy ,disulfide-rich peptide ,conotoxin ,Medicine - Abstract
Structural analysis of peptides with nuclear magnetic resonance (NMR) spectroscopy generally relies on knowledge of the primary sequence to enable assignment of the resonances prior to determination of the three-dimensional structure. Resonance assignment without knowledge of the sequence is complicated by redundancy in amino acid type, making complete de novo sequencing using NMR spectroscopy unlikely to be feasible. Despite this redundancy, we show here that NMR spectroscopy can be used to identify short sequence tags that can be used to elucidate full-length peptide sequences via database searching. In the current study, we have used this approach to identify conotoxins from the venom of the cone snail Conus geographus and determined the three-dimensional structure of a member of the I3 superfamily. This approach is most likely to be useful for the characterization of disulfide-rich peptides, such as those that were chosen for this study, as they generally have well-defined structures, which enhances the quality of the NMR spectra. In contrast to other sequencing methods, the lack of sample manipulation, such as protease digestion, allows for subsequent bioassays to be carried out using the native sample used for sequence identification.
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- 2018
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83. Structural Characterisation of Predicted Helical Regions in the Chironex fleckeri CfTX-1 Toxin
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Athena Andreosso, Paramjit S. Bansal, Michael J. Smout, David Wilson, Jamie E. Seymour, and Norelle L. Daly
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Chironex fleckeri venom ,CfTX-1 ,cubozoan toxins ,pore-forming toxins ,Biology (General) ,QH301-705.5 - Abstract
The Australian jellyfish Chironex fleckeri, belongs to a family of cubozoan jellyfish known for their potent venoms. CfTX-1 and -2 are two highly abundant toxins in the venom, but there is no structural data available for these proteins. Structural information on toxins is integral to the understanding of the mechanism of these toxins and the development of an effective treatment. Two regions of CfTX-1 have been predicted to have helical structures that are involved with the mechanism of action. Here we have synthesized peptides corresponding to these regions and analyzed their structures using NMR spectroscopy. The peptide corresponding to the predicted N-terminal amphiphilic helix appears unstructured in aqueous solution. This lack of structure concurs with structural disorder predicted for this region of the protein using the Protein DisOrder prediction System PrDOS. Conversely, a peptide corresponding to a predicted transmembrane region is very hydrophobic, insoluble in aqueous solution and predicted to be structured by PrDOS. In the presence of SDS-micelles both peptides have well-defined helical structures showing that a membrane mimicking environment stabilizes the structures of both peptides and supports the prediction of the transmembrane region in CfTX-1. This is the first study to experimentally analyze the structure of regions of a C. fleckeri protein.
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- 2018
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84. Synthesis, Structure and Biological Activity of CIA and CIB, Two α-Conotoxins from the Predation-Evoked Venom of Conus catus
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Julien Giribaldi, David Wilson, Annette Nicke, Yamina El Hamdaoui, Guillaume Laconde, Adèle Faucherre, Hamid Moha Ou Maati, Norelle L. Daly, Christine Enjalbal, and Sébastien Dutertre
- Subjects
conotoxins ,Conus catus ,electrophysiology ,in vivo ,nicotinic receptors ,structure ,synthesis ,Medicine - Abstract
Cone snails produce a fast-acting and often paralyzing venom that is usually injected into their prey or predator through a hypodermic needle-like modified radula tooth. Many diverse compounds are found in their venom including small molecules, peptides and enzymes. However, peptidic toxins called conotoxins (10–40 residues and 2–4 disulfide bonds) largely dominate these cocktails. These disulfide rich toxins are very valuable pharmacological tools for investigating the function of ions channels, G-protein coupled receptors, transporters and enzymes. Here, we report on the synthesis, structure determination and biological activities of two α-conotoxins, CIA and CIB, found in the predatory venom of the piscivorous species Conus catus. CIA is a typical 3/5 α-conotoxin that blocks the rat muscle type nAChR with an IC50 of 5.7 nM. Interestingly, CIA also inhibits the neuronal rat nAChR subtype α3β2 with an IC50 of 2.06 μM. CIB is a 4/7 α-conotoxin that blocks rat neuronal nAChR subtypes, including α3β2 (IC50 = 128.9 nM) and α7 (IC50 = 1.51 μM). High resolution NMR structures revealed typical α-conotoxin folds for both peptides. We also investigated the in vivo effects of these toxins on fish, since both peptides were identified in the predatory venom of C. catus. Consistent with their pharmacology, CIA was highly paralytic to zebrafish (ED50 = 110 μg/kg), whereas CIB did not affect the mobility of the fish. In conclusion, CIA likely participates in prey capture through muscle paralysis, while the putative ecological role of CIB remains to be elucidated.
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- 2018
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85. The Venom of the Spine-Bellied Sea Snake (Hydrophis curtus): Proteome, Toxin Diversity and Intraspecific Variation
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Vanessa Neale, Javier Sotillo, Jamie E. Seymour, and David Wilson
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Hydrophis curtus ,spine-bellied sea snake ,sea snake venom ,venom proteome ,venomics ,intraspecific variation ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The spine-bellied sea snake (Hydrophis curtus) is known to cause human deaths, yet its venom composition has not yet been proteomically characterised. An in-depth proteomic analysis was performed on H. curtus venom from two different seasons, January and June, corresponding to adults and subadults, respectively. Venoms from adult and subadult H. curtus individuals were compared using reversed-phase high-performance liquid chromatography (RP-HPLC), matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF) mass spectrometry and liquid chromatography electrospray ionisation mass spectrometry (LC-ESI-MS) to detect intraspecific variation, and the molecular weight data obtained with ESI-MS were used to assess toxin diversity. RP-HPLC and LC-ESI-MS/MS were used to characterise the venom proteome and estimate the relative abundances of protein families present. The most abundant protein family in January and June venoms is phospholipase A2 (PLA2: January 66.7%; June 54.5%), followed by three-finger toxins (3FTx: January 30.4%; June 40.4%) and a minor component of cysteine-rich secretory proteins (CRISP: January 2.5%; June 5%). Trace amounts of snake venom metalloproteinases (SVMP), C-type lectins and housekeeping and regulatory proteins were also found. Although the complexity of the venom is low by number of families present, each family contained a more diverse set of isoforms than previously reported, a finding that may have implications for the development of next-generation sea snake antivenoms. Intraspecific variability was shown to be minor with one obvious exception of a 14,157-Da protein that was present in some January (adult) venoms, but not at all in June (subadult) venoms. There is also a greater abundance of short-chain neurotoxins in June (subadult) venom compared with January (adult) venom. These differences potentially indicate the presence of seasonal, ontogenetic or sexual variation in H. curtus venom.
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- 2017
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86. HIV Programs for Sex Workers: Lessons and Challenges for Developing and Delivering Programs.
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David Wilson
- Subjects
Medicine - Abstract
There is evidence that HIV prevention programs for sex workers, especially female sex workers, are cost-effective in several contexts, including many western countries, Thailand, India, the Democratic Republic of Congo, Kenya, and Zimbabwe. The evidence that sex worker HIV prevention programs work must not inspire complacency but rather a renewed effort to expand, intensify, and maximize their impact. The PLOS Collection "Focus on Delivery and Scale: Achieving HIV Impact with Sex Workers" highlights major challenges to scaling-up sex worker HIV prevention programs, noting the following: sex worker HIV prevention programs are insufficiently guided by understanding of epidemic transmission dynamics, situation analyses, and programmatic mapping; sex worker HIV and sexually transmitted infection services receive limited domestic financing in many countries; many sex worker HIV prevention programs are inadequately codified to ensure consistency and quality; and many sex worker HIV prevention programs have not evolved adequately to address informal sex workers, male and transgender sex workers, and mobile- and internet-based sex workers. Based on the wider collection of papers, this article presents three major clusters of recommendations: (i) HIV programs focused on sex workers should be prioritized, developed, and implemented based on robust evidence; (ii) national political will and increased funding are needed to increase coverage of effective sex worker HIV prevention programs in low and middle income countries; and (iii) comprehensive, integrated, and rapidly evolving HIV programs are needed to ensure equitable access to health services for individuals involved in all forms of sex work.
- Published
- 2015
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87. Factors Associated with Variations in Population HIV Prevalence across West Africa: Findings from an Ecological Analysis.
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Holly J Prudden, Tara S Beattie, Natalia Bobrova, Jasmina Panovska-Griffiths, Zindoga Mukandavire, Marelize Gorgens, David Wilson, and Charlotte H Watts
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Medicine ,Science - Abstract
BACKGROUND:Population HIV prevalence across West Africa varies substantially. We assess the national epidemiological and behavioural factors associated with this. METHODS:National, urban and rural data on HIV prevalence, the percentage of younger (15-24) and older (25-49) women and men reporting multiple (2+) partners in the past year, HIV prevalence among female sex workers (FSWs), men who have bought sex in the past year (clients), and ART coverage, were compiled for 13 countries. An Ecological analysis using linear regression assessed which factors are associated with national variations in population female and male HIV prevalence, and with each other. FINDINGS:National population HIV prevalence varies between 0 4-2 9% for men and 0 4-5.6% for women. ART coverage ranges from 6-23%. National variations in HIV prevalence are not shown to be associated with variations in HIV prevalence among FSWs or clients. Instead they are associated with variations in the percentage of younger and older males and females reporting multiple partners. HIV prevalence is weakly negatively associated with ART coverage, implying it is not increased survival that is the cause of variations in HIV prevalence. FSWs and younger female HIV prevalence are associated with client population sizes, especially older men. Younger female HIV prevalence is strongly associated with older male and female HIV prevalence. INTERPRETATION:In West Africa, population HIV prevalence is not significantly higher in countries with high FSW HIV prevalence. Our analysis suggests, higher prevalence occurs where more men buy sex, and where a higher percentage of younger women, and older men and women have multiple partnerships. If a sexual network between clients and young females exists, clients may potentially bridge infection to younger females. HIV prevention should focus both on commercial sex and transmission between clients and younger females with multiple partners.
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- 2015
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88. A aplicação dos princípios gerais do direito ao caso da dívida externa dos países do Sul na ordem cosmopolita
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David Wilson de Abreu Pardo
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Divida externa ,Paises do Cone Sul ,Direito Comercial ,Law ,Law in general. Comparative and uniform law. Jurisprudence ,K1-7720 - Published
- 2002
89. The Aromatic Head Group of Spider Toxin Polyamines Influences Toxicity to Cancer Cells
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David Wilson, Glen M. Boyle, Lachlan McIntyre, Matthew J. Nolan, Peter G. Parsons, Jennifer J. Smith, Leon Tribolet, Alex Loukas, Michael J. Liddell, Lachlan D. Rash, and Norelle L. Daly
- Subjects
spider venom ,NMR spectroscopy ,polyamine ,cancer ,cytotoxicity ,Medicine - Abstract
Spider venoms constitute incredibly diverse libraries of compounds, many of which are involved in prey capture and defence. Polyamines are often prevalent in the venom and target ionotropic glutamate receptors. Here we show that a novel spider polyamine, PA366, containing a hydroxyphenyl-based structure is present in the venom of several species of tarantula, and has selective toxicity against MCF-7 breast cancer cells. By contrast, a polyamine from an Australian funnel-web spider venom, which contains an identical polyamine tail to PA366 but an indole-based head-group, is only cytotoxic at high concentrations. Our results suggest that the ring structure plays a role in the cytotoxicity and that modification to the polyamine head group might lead to more potent and selective compounds with potential as novel cancer treatments.
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- 2017
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90. System Identification of a Heaving Point Absorber: Design of Experiment and Device Modeling
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Giorgio Bacelli, Ryan G. Coe, David Patterson, and David Wilson
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wave energy ,system identification ,model validation ,wave tank testing ,Technology - Abstract
Empirically based modeling is an essential aspect of design for a wave energy converter. Empirically based models are used in structural, mechanical and control design processes, as well as for performance prediction. Both the design of experiments and methods used in system identification have a strong impact on the quality of the resulting model. This study considers the system identification and model validation process based on data collected from a wave tank test of a model-scale wave energy converter. Experimental design and data processing techniques based on general system identification procedures are discussed and compared with the practices often followed for wave tank testing. The general system identification processes are shown to have a number of advantages, including an increased signal-to-noise ratio, reduced experimental time and higher frequency resolution. The experimental wave tank data is used to produce multiple models using different formulations to represent the dynamics of the wave energy converter. These models are validated and their performance is compared against one another. While most models of wave energy converters use a formulation with surface elevation as an input, this study shows that a model using a hull pressure measurement to incorporate the wave excitation phenomenon has better accuracy.
- Published
- 2017
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91. HIV among people who inject drugs in the Middle East and North Africa: systematic review and data synthesis.
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Ghina R Mumtaz, Helen A Weiss, Sara L Thomas, Suzanne Riome, Hamidreza Setayesh, Gabriele Riedner, Iris Semini, Oussama Tawil, Francisca Ayodeji Akala, David Wilson, and Laith J Abu-Raddad
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Medicine - Abstract
It is perceived that little is known about the epidemiology of HIV infection among people who inject drugs (PWID) in the Middle East and North Africa (MENA). The primary objective of this study was to assess the status of the HIV epidemic among PWID in MENA by describing HIV prevalence and incidence. Secondary objectives were to describe the risk behavior environment and the HIV epidemic potential among PWID, and to estimate the prevalence of injecting drug use in MENA.This was a systematic review following the PRISMA guidelines and covering 23 MENA countries. PubMed, Embase, regional and international databases, as well as country-level reports were searched up to December 16, 2013. Primary studies reporting (1) the prevalence/incidence of HIV, other sexually transmitted infections, or hepatitis C virus (HCV) among PWIDs; or (2) the prevalence of injecting or sexual risk behaviors, or HIV knowledge among PWID; or (3) the number/proportion of PWID in MENA countries, were eligible for inclusion. The quality, quantity, and geographic coverage of the data were assessed at country level. Risk of bias in predefined quality domains was described to assess the quality of available HIV prevalence measures. After multiple level screening, 192 eligible reports were included in the review. There were 197 HIV prevalence measures on a total of 58,241 PWID extracted from reports, and an additional 226 HIV prevalence measures extracted from the databases. We estimated that there are 626,000 PWID in MENA (range: 335,000-1,635,000, prevalence of 0.24 per 100 adults). We found evidence of HIV epidemics among PWID in at least one-third of MENA countries, most of which are emerging concentrated epidemics and with HIV prevalence overall in the range of 10%-15%. Some of the epidemics have however already reached considerable levels including some of the highest HIV prevalence among PWID globally (87.1% in Tripoli, Libya). The relatively high prevalence of sharing needles/syringes (18%-28% in the last injection), the low levels of condom use (20%-54% ever condom use), the high levels of having sex with sex workers and of men having sex with men (15%-30% and 2%-10% in the last year, respectively), and of selling sex (5%-29% in the last year), indicate a high injecting and sexual risk environment. The prevalence of HCV (31%-64%) and of sexually transmitted infections suggest high levels of risk behavior indicative of the potential for more and larger HIV epidemics.Our study identified a large volume of HIV-related biological and behavioral data among PWID in the MENA region. The coverage and quality of the data varied between countries. There is robust evidence for HIV epidemics among PWID in multiple countries, most of which have emerged within the last decade and continue to grow. The lack of sufficient evidence in some MENA countries does not preclude the possibility of hidden epidemics among PWID in these settings. With the HIV epidemic among PWID in overall a relatively early phase, there is a window of opportunity for prevention that should not be missed through the provision of comprehensive programs, including scale-up of harm reduction services and expansion of surveillance systems.
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- 2014
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92. Percutaneous vertebroplasty and percutaneous balloon kyphoplasty for the treatment of osteoporotic vertebral fractures: a systematic review and cost-effectiveness analysis
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Matt Stevenson, Tim Gomersall, Myfanwy Lloyd Jones, Andrew Rawdin, Monica Hernández, Sofia Dias, David Wilson, and Angie Rees
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percutaneous vertebroplasty ,percutaneous balloon kyphoplasty ,systematic review ,cost-effectiveness analysis ,osteoporotic vertebral fractures ,Medical technology ,R855-855.5 - Abstract
Background: Percutaneous vertebroplasty (PVP) is a minimally invasive surgical procedure in which bone cement is injected into a fractured vertebra. Percutaneous balloon kyphoplasty (BKP) is a variation of this approach, in which an inflatable balloon tamp is placed in the collapsed vertebra prior to cement injection. Objectives: To systematically evaluate and appraise the clinical effectiveness and cost-effectiveness of PVP and percutaneous BKP in reducing pain and disability in people with osteoporotic vertebral compression fractures (VCFs) in England and Wales. Data sources: A systematic review was carried out. Ten databases including MEDLINE and CINAHL were searched from inception to November 2011, and supplemented by hand-searching relevant articles and contact with an expert. Studies met the inclusion criteria if they were randomised controlled trials (RCTs) including people with painful osteoporotic VCFs with a group receiving PVP or BKP. In addition, lead authors of identified RCTs were contacted for unpublished data. Review methods: Primary outcomes were health-related quality of life; back-specific functional status/mobility; pain/analgesic use; vertebral body height and angular deformity; incidence of new vertebral fractures and progression of treated fracture. A manufacturer provided academic-in-confidence observational data indicating that vertebral augmentation may be associated with a beneficial mortality effect, and that, potentially, BKP was more efficacious than PVP. These data were formally critiqued. A mathematical model was constructed to explore the cost-effectiveness of BKP, PVP and operative placebo with local anaesthesia (OPLA) compared with optimal pain management (OPM). Six scenario analyses were conducted that assessed combinations of assumptions on mortality (differential beneficial effects for BKP and PVP; equal beneficial effects for BKP and PVP; and no effect assumed) and derivation of utility data (either mapped from visual analogue scale pain score data produced by a network meta-analysis or using direct European Quality of Life-5 Dimensions data from the trials). Extensive sensitivity analyses were conducted on each of the six scenarios. This report contains reference to confidential information provided as part of the National Institute for Health and Care Excellence appraisal process. This information has been removed from the report and the results, discussions and conclusions of the report do not include the confidential information. These sections are clearly marked in the report. Results: A total of nine RCTs were identified and included in the review of clinical effectiveness. This body of literature was of variable quality, with the two double-blind, OPLA-controlled trials being at the least risk of bias. The most significant methodological issue among the remaining trials was lack of blinding for both study participants and outcome assessors. Broadly speaking, the literature suggests that both PVP and BKP provide substantially greater benefits than OPM in open-label trials. However, in double-blinded trials PVP was shown to have no more benefit than local anaesthetic; no trials of BKP compared with local anaesthesia have been conducted. A formal analysis of observational mortality data undertaken within this report concluded that it was not possible to say with certainty if there is a difference in mortality between patients undergoing BKP and PVP compared with OPM. Results from the cost-effectiveness analyses were varied, with all of BKP, PVP and OPLA appearing the most cost-effective treatment dependent on the assumptions made regarding mortality effects, utility, hospitalisation costs and OPLA costs. Limitations: Data on key parameters were uncertain and/or potentially confounded, making definitive conclusions difficult to make. Conclusion: For people with painful osteoporotic VCFs refractory to analgesic treatment, PVP and BKP perform significantly better in unblinded trials than OPM in terms of improving quality of life and reducing pain and disability. However, there is as yet no convincing evidence that either procedure performs better than OPLA. The uncertainty in the evidence base means that no definitive conclusion on the cost-effectiveness of PVP or BKP can be provided. Further research should focus on establishing whether or not BKP and PVP have a mortality advantage compared with OPLA and on whether or not these provide any utility gain compared with OPLA. Study registration: This study was registered as PROSPERO number CRD42011001822. Funding: The National Institute for Health Research Health Technology Assessment programme.
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- 2014
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93. Spending of HIV resources in Asia and Eastern Europe: systematic review reveals the need to shift funding allocations towards priority populations
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Andrew P Craig, Hla‐Hla Thein, Lei Zhang, Richard T Gray, Klara Henderson, David Wilson, Marelize Gorgens, and David P Wilson
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HIV ,cost‐benefit analyses ,programme evaluation ,systematic review ,concentrated epidemics ,Asia ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Introduction It is increasingly important to prioritize the most cost‐effective HIV interventions. We sought to summarize the evidence on which types of interventions provide the best value for money in regions with concentrated HIV epidemics. Methods We conducted a systematic review of peer‐reviewed and grey literature reporting measurements of cost‐effectiveness or cost‐benefit for HIV/AIDS interventions in Asia and Eastern Europe. We also collated HIV/AIDS spending assessment data from case‐study countries in the region. Results We identified 91 studies for inclusion, 47 of which were from peer‐reviewed journals. Generally, in concentrated settings, prevention of mother‐to‐child transmission programmes and prevention programmes targeting people who inject drugs and sex workers had lower incremental cost‐effectiveness ratios than programmes aimed at the general population. The few studies evaluating programmes targeting men who have sex with men indicate moderate cost‐effectiveness. Collation of prevention programme spending data from 12 countries in the region (none of which had generalized epidemics) indicated that resources for the general population/non‐targeted was greater than 30% for eight countries and greater than 50% for five countries. Conclusions There is a misalignment between national spending on HIV/AIDS responses and the most affected populations across the region. In concentrated epidemics, scarce funding should be directed more towards most‐at‐risk populations. Reaching consensus on general principles of cost‐effectiveness of programmes by epidemic settings is difficult due to inconsistent evaluation approaches. Adopting a standard costing, impact evaluation, benefits calculation, analysis and reporting framework would enable cross comparisons and improve HIV resource prioritization and allocation.
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- 2014
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94. Observed agreement problems between sub-scales and summary components of the SF-36 version 2 - an alternative scoring method can correct the problem.
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Graeme Tucker, Robert Adams, and David Wilson
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Medicine ,Science - Abstract
PURPOSE: A number of previous studies have shown inconsistencies between sub-scale scores and component summary scores using traditional scoring methods of the SF-36 version 1. This study addresses the issue in Version 2 and asks if the previous problems of disagreement between the eight SF-36 Version 1 sub-scale scores and the Physical and Mental Component Summary persist in version 2. A second study objective is to review the recommended scoring methods for the creation of factor scoring weights and the effect on producing summary scale scores. METHODS: The 2004 South Australian Health Omnibus Survey dataset was used for the production of coefficients. There were 3,014 observations with full data for the SF-36. Data were analysed in LISREL V8.71. Confirmatory factor analysis models were fit to the data producing diagonally weighted least squares estimates. Scoring coefficients were validated on an independent dataset, the 2008 South Australian Health Omnibus Survey. RESULTS: Problems of agreement were observed with the recommended orthogonal scoring methods which were corrected using confirmatory factor analysis. CONCLUSIONS: Confirmatory factor analysis is the preferred method to analyse SF-36 data, allowing for the correlation between physical and mental health.
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- 2013
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95. HIV epidemic appraisals for assisting in the design of effective prevention programmes: shifting the paradigm back to basics.
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Sharmistha Mishra, Sema K Sgaier, Laura H Thompson, Stephen Moses, B M Ramesh, Michel Alary, David Wilson, and James F Blanchard
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Medicine ,Science - Abstract
BackgroundTo design HIV prevention programmes, it is critical to understand the temporal and geographic aspects of the local epidemic and to address the key behaviours that drive HIV transmission. Two methods have been developed to appraise HIV epidemics and guide prevention strategies. The numerical proxy method classifies epidemics based on current HIV prevalence thresholds. The Modes of Transmission (MOT) model estimates the distribution of incidence over one year among risk-groups. Both methods focus on the current state of an epidemic and provide short-term metrics which may not capture the epidemiologic drivers. Through a detailed analysis of country and sub-national data, we explore the limitations of the two traditional methods and propose an alternative approach.Methods and findingsWe compared outputs of the traditional methods in five countries for which results were published, and applied the numeric and MOT model to India and six districts within India. We discovered three limitations of the current methods for epidemic appraisal: (1) their results failed to identify the key behaviours that drive the epidemic; (2) they were difficult to apply to local epidemics with heterogeneity across district-level administrative units; and (3) the MOT model was highly sensitive to input parameters, many of which required extraction from non-regional sources. We developed an alternative decision-tree framework for HIV epidemic appraisals, based on a qualitative understanding of epidemiologic drivers, and demonstrated its applicability in India. The alternative framework offered a logical algorithm to characterize epidemics; it required minimal but key data.ConclusionsTraditional appraisals that utilize the distribution of prevalent and incident HIV infections in the short-term could misguide prevention priorities and potentially impede efforts to halt the trajectory of the HIV epidemic. An approach that characterizes local transmission dynamics provides a potentially more effective tool with which policy makers can design intervention programmes.
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- 2012
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96. HIV treatment as prevention: principles of good HIV epidemiology modelling for public health decision-making in all modes of prevention and evaluation.
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Wim Delva, David P Wilson, Laith Abu-Raddad, Marelize Gorgens, David Wilson, Timothy B Hallett, and Alex Welte
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Medicine - Abstract
Public health responses to HIV epidemics have long relied on epidemiological modelling analyses to help prospectively project and retrospectively estimate the impact, cost-effectiveness, affordability, and investment returns of interventions, and to help plan the design of evaluations. But translating model output into policy decisions and implementation on the ground is challenged by the differences in background and expectations of modellers and decision-makers. As part of the PLoS Medicine Collection "Investigating the Impact of Treatment on New HIV Infections"--which focuses on the contribution of modelling to current issues in HIV prevention--we present here principles of "best practice" for the construction, reporting, and interpretation of HIV epidemiological models for public health decision-making on all aspects of HIV. Aimed at both those who conduct modelling research and those who use modelling results, we hope that the principles described here will become a shared resource that facilitates constructive discussions about the policy implications that emerge from HIV epidemiology modelling results, and that promotes joint understanding between modellers and decision-makers about when modelling is useful as a tool in quantifying HIV epidemiological outcomes and improving prevention programming.
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- 2012
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97. The lethal toxin from Australian funnel-web spiders is encoded by an intronless gene.
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Sandy Steffany Pineda, David Wilson, John S Mattick, and Glenn F King
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Medicine ,Science - Abstract
Australian funnel-web spiders are generally considered the most dangerous spiders in the world, with envenomations from the Sydney funnel-web spider Atrax robustus resulting in at least 14 human fatalities prior to the introduction of an effective anti-venom in 1980. The clinical envenomation syndrome resulting from bites by Australian funnel-web spiders is due to a single 42-residue peptide known as δ-hexatoxin. This peptide delays the inactivation of voltage-gated sodium channels, which results in spontaneous repetitive firing and prolongation of action potentials, thereby causing massive neurotransmitter release from both somatic and autonomic nerve endings. Here we show that δ-hexatoxin from the Australian funnel-web spider Hadronyche versuta is produced from an intronless gene that encodes a prepropeptide that is post-translationally processed to yield the mature toxin. A limited sampling of genes encoding unrelated venom peptides from this spider indicated that they are all intronless. Thus, in distinct contrast to cone snails and scorpions, whose toxin genes contain introns, spiders may have developed a quite different genetic strategy for evolving their venom peptidome.
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- 2012
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98. Automated Lobe-Based Airway Labeling
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Suicheng Gu, Zhimin Wang, Jill M. Siegfried, David Wilson, William L. Bigbee, and Jiantao Pu
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Medical physics. Medical radiology. Nuclear medicine ,R895-920 ,Medical technology ,R855-855.5 - Abstract
Regional quantitative analysis of airway morphological abnormalities is of great interest in lung disease investigation. Considering that pulmonary lobes are relatively independent functional unit, we develop and test a novel and efficient computerized scheme in this study to automatically and robustly classify the airways into different categories in terms of pulmonary lobe. Given an airway tree, which could be obtained using any available airway segmentation scheme, the developed approach consists of four basic steps: (1) airway skeletonization or centerline extraction, (2) individual airway branch identification, (3) initial rule-based airway classification/labeling, and (4) self-correction of labeling errors. In order to assess the performance of this approach, we applied it to a dataset consisting of 300 chest CT examinations in a batch manner and asked an image analyst to subjectively examine the labeled results. Our preliminary experiment showed that the labeling accuracy for the right upper lobe, the right middle lobe, the right lower lobe, the left upper lobe, and the left lower lobe is 100%, 99.3%, 99.3%, 100%, and 100%, respectively. Among these, only two cases are incorrectly labeled due to the failures in airway detection. It takes around 2 minutes to label an airway tree using this algorithm.
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- 2012
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99. The related transcriptional enhancer factor-1 isoform, TEAD4(216), can repress vascular endothelial growth factor expression in mammalian cells.
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Binoy Appukuttan, Trevor J McFarland, Andrew Stempel, Jean B Kassem, Matthew Hartzell, Yi Zhang, Derek Bond, Kelsey West, Reid Wilson, Andrew Stout, Yuzhen Pan, Hoda Ilias, Kathryn Robertson, Michael L Klein, David Wilson, Justine R Smith, and J Timothy Stout
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Medicine ,Science - Abstract
Increased cellular production of vascular endothelial growth factor (VEGF) is responsible for the development and progression of multiple cancers and other neovascular conditions, and therapies targeting post-translational VEGF products are used in the treatment of these diseases. Development of methods to control and modify the transcription of the VEGF gene is an alternative approach that may have therapeutic potential. We have previously shown that isoforms of the transcriptional enhancer factor 1-related (TEAD4) protein can enhance the production of VEGF. In this study we describe a new TEAD4 isoform, TEAD4(216), which represses VEGF promoter activity. The TEAD4(216) isoform inhibits human VEGF promoter activity and does not require the presence of the hypoxia responsive element (HRE), which is the sequence critical to hypoxia inducible factor (HIF)-mediated effects. The TEAD4(216) protein is localized to the cytoplasm, whereas the enhancer isoforms are found within the nucleus. The TEAD4(216) isoform can competitively repress the stimulatory activity of the TEAD4(434) and TEAD4(148) enhancers. Synthesis of the native VEGF(165) protein and cellular proliferation is suppressed by the TEAD4(216) isoform. Mutational analysis indicates that nuclear or cytoplasmic localization of any isoform determines whether it acts as an enhancer or repressor, respectively. The TEAD4(216) isoform appears to inhibit VEGF production independently of the HRE required activity by HIF, suggesting that this alternatively spliced isoform of TEAD4 may provide a novel approach to treat VEGF-dependent diseases.
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- 2012
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100. Are HIV epidemics among men who have sex with men emerging in the Middle East and North Africa?: a systematic review and data synthesis.
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Ghina Mumtaz, Nahla Hilmi, Willi McFarland, Rachel L Kaplan, Francisca Ayodeji Akala, Iris Semini, Gabriele Riedner, Oussama Tawil, David Wilson, and Laith J Abu-Raddad
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Medicine - Abstract
BACKGROUND: Men who have sex with men (MSM) bear a disproportionately higher burden of HIV infection than the general population. MSM in the Middle East and North Africa (MENA) are a largely hidden population because of a prevailing stigma towards this type of sexual behavior, thereby limiting the ability to assess infection transmission patterns among them. It is widely perceived that data are virtually nonexistent on MSM and HIV in this region. The objective of this review was to delineate, for the first time, the evidence on the epidemiology of HIV among MSM in MENA. METHODS AND FINDINGS: This was a systematic review of all biological, behavioral, and other related data on HIV and MSM in MENA. Sources of data included PubMed (Medline), international organizations' reports and databases, country-level reports and databases including governmental and nongovernmental organization publications, and various other institutional documents. This review showed that onsiderable data are available on MSM and HIV in MENA. While HIV prevalence continues at low levels among different MSM groups, HIV epidemics appear to be emerging in at least few countries, with a prevalence reaching up to 28% among certain MSM groups. By 2008, the contribution of MSM transmission to the total HIV notified cases increased and exceeded 25% in several countries. The high levels of risk behavior (4-14 partners on average in the last six months among different MSM populations) and of biomarkers of risks (such as herpes simplex virus type 2 at 3%-54%), the overall low rate of consistent condom use (generally below 25%), the relative frequency of male sex work (20%-76%), and the substantial overlap with heterosexual risk behavior and injecting drug use suggest potential for further spread. CONCLUSIONS: This systematic review and data synthesis indicate that HIV epidemics appear to be emerging among MSM in at least a few MENA countries and could already be in a concentrated state among several MSM groups. There is an urgent need to expand HIV surveillance and access to HIV testing, prevention, and treatment services in a rapidly narrowing window of opportunity to prevent the worst of HIV transmission among MSM in the Middle East and North Africa. Please see later in the article for the Editors' Summary.
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- 2010
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