Institution
McMaster University
Education•Hamilton, Ontario, Canada•
About: McMaster University is a education organization based out in Hamilton, Ontario, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 41361 authors who have published 101269 publications receiving 4251422 citations.
Papers published on a yearly basis
Papers
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TL;DR: Cl clot-bound thrombin is relatively protected from inhibition by heparin, and antithrombin III-independent inhibitors may be more effective than hepar in certain clinical settings.
Abstract: Propagation of venous thrombi or rethrombosis after coronary thrombolytic therapy can occur despite heparin administration. To explore potential mechanisms, we set out to determine whether clot-bound thrombin is relatively protected from inhibition by heparin-antithrombin III but susceptible to inactivation by antithrombin III-independent inhibitors. Using plasma fibrinopeptide A (FPA) levels as an index of thrombin activity, we compared the ability of thrombin inhibitors to block FPA release mediated by fluid-phase thrombin with their activity against the clot-bound enzyme. Incubation of thrombin with citrated plasma results in concentration-dependent FPA generation, which reaches a plateau within minutes. In contrast, there is progressive FPA generation when fibrin clots are incubated with citrated plasma. Heparin, hirudin, hirudin dodecapeptide (hirugen), and D-phenylalanyl-L-prolyl-L-arginyl chloromethyl ketone (PPACK) produce concentration-dependent inhibition of FPA release mediated by fluid-phase thrombin. However, heparin is much less effective at inhibiting thrombin bound to fibrin because a 20-fold higher concentration is necessary to block 70% of the activity of the clot-bound enzyme than is required for equivalent inhibition of fluid-phase thrombin (2.0 and 0.1 U/ml, respectively). In contrast, hirugen and PPACK are equally effective inhibitors of fluid- and solid-phase thrombin, while hirudin is only 50% as effective against the clot-bound enzyme. None of the inhibitors displace bound 125I-labeled thrombin from the clot. These studies indicate that (a) clot-bound thrombin is relatively protected from inhibition by heparin, possibly because the heparin binding site on thrombin is inaccessible when the enzyme is bound to fibrin, and (b) clot-bound thrombin is susceptible to inactivation by antithrombin III-independent inhibitors because the sites of their interaction are not masked by thrombin binding to fibrin. For these reasons, antithrombin III-independent inhibitors may be more effective than heparin in certain clinical settings.
1,115 citations
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Children's Hospital of Eastern Ontario1, University of Ottawa2, University of Alberta3, Public Health Agency of Canada4, Conference Board of Canada5, University of British Columbia6, Douglas Mental Health University Institute7, Queen's University8, Pennington Biomedical Research Center9, McMaster University10, McGill University11, University of Wollongong12, University of South Australia13, University of South Carolina14, University of Prince Edward Island15, University of Calgary16, Swansea University17, University of Toronto18, Camosun College19
TL;DR: The Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep provide evidence-informed recommendations for a healthy day (24 h), comprising a combination of sleep, sedentary behaviours, light-, moderate-, and vigorous-intensity physical activity.
Abstract: Leaders from the Canadian Society for Exercise Physiology convened representatives of national organizations, content experts, methodologists, stakeholders, and end-users who followed rigorous and transparent guideline development procedures to create the Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep. These novel guidelines for children and youth aged 5-17 years respect the natural and intuitive integration of movement behaviours across the whole day (24-h period). The development process was guided by the Appraisal of Guidelines for Research Evaluation (AGREE) II instrument and systematic reviews of evidence informing the guidelines were assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Four systematic reviews (physical activity, sedentary behaviour, sleep, integrated behaviours) examining the relationships between and among movement behaviours and several health indicators were completed and interpreted by expert consensus. Complementary compositional analyses were performed using Canadian Health Measures Survey data to examine the relationships between movement behaviours and health indicators. A stakeholder survey was employed (n = 590) and 28 focus groups/stakeholder interviews (n = 104) were completed to gather feedback on draft guidelines. Following an introductory preamble, the guidelines provide evidence-informed recommendations for a healthy day (24 h), comprising a combination of sleep, sedentary behaviours, light-, moderate-, and vigorous-intensity physical activity. Proactive dissemination, promotion, implementation, and evaluation plans have been prepared in an effort to optimize uptake and activation of the new guidelines. Future research should consider the integrated relationships among movement behaviours, and similar integrated guidelines for other age groups should be developed.
1,114 citations
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TL;DR: The Inflammatory Bowel Disease Questionnaire shows promise as a measure of health status for clinical trials in IBD, and responsiveness appeared greater in patients with ulcerative colitis than in those with Crohn's disease.
1,111 citations
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1,111 citations
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24 May 2012TL;DR: Downregulation of intracortical inhibition induced by damage to the cochlea or to auditory projection pathways highlights neural processes that underlie the sensation of phantom sound.
Abstract: Tinnitus is an auditory phantom sensation (ringing of the ears) experienced when no external sound is present. Most but not all cases are associated with hearing loss induced by noise exposure or aging. Neuroscience research has begun to reveal how tinnitus is generated by the brain when hearing loss occurs, and to suggest new avenues for management and prevention of tinnitus following hearing injuries. Downregulation of intracortical inhibition induced by damage to the cochlea or to auditory projection pathways highlights neural processes that underlie the sensation of phantom sound.
1,109 citations
Authors
Showing all 41721 results
Name | H-index | Papers | Citations |
---|---|---|---|
Salim Yusuf | 231 | 1439 | 252912 |
Gordon H. Guyatt | 231 | 1620 | 228631 |
Simon D. M. White | 189 | 795 | 231645 |
George Efstathiou | 187 | 637 | 156228 |
Stuart H. Orkin | 186 | 715 | 112182 |
Terrie E. Moffitt | 182 | 594 | 150609 |
John J.V. McMurray | 178 | 1389 | 184502 |
Jasvinder A. Singh | 176 | 2382 | 223370 |
Deborah J. Cook | 173 | 907 | 148928 |
Andrew P. McMahon | 162 | 415 | 90650 |
Jack Hirsh | 146 | 734 | 86332 |
Holger J. Schünemann | 141 | 810 | 113169 |
John A. Peacock | 140 | 565 | 125416 |
David Price | 138 | 1687 | 93535 |
Graeme J. Hankey | 137 | 844 | 143373 |