McMaster University

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.

Myocardial Injury after Noncardiac Surgery: A Large, International, Prospective Cohort Study Establishing Diagnostic Criteria, Characteristics, Predictors, and 30-day Outcomes

Abstract: Background Myocardial injury after noncardiac surgery (MINS) was defined as prognostically relevant myocardial injury due to ischemia that occurs during or within 30 days after noncardiac surgery. The study's four objectives were to determine the diagnostic criteria, characteristics, predictors, and 30-day outcomes of MINS. Methods In this international, prospective cohort study of 15,065 patients aged 45 yr or older who underwent in-patient noncardiac surgery, troponin T was measured during the first 3 postoperative days. Patients with a troponin T level of 0.04 ng/ml or greater (elevated "abnormal" laboratory threshold) were assessed for ischemic features (i.e., ischemic symptoms and electrocardiography findings). Patients adjudicated as having a nonischemic troponin elevation (e.g., sepsis) were excluded. To establish diagnostic criteria for MINS, the authors used Cox regression analyses in which the dependent variable was 30-day mortality (260 deaths) and independent variables included preoperative variables, perioperative complications, and potential MINS diagnostic criteria. Results An elevated troponin after noncardiac surgery, irrespective of the presence of an ischemic feature, independently predicted 30-day mortality. Therefore, the authors' diagnostic criterion for MINS was a peak troponin T level of 0.03 ng/ml or greater judged due to myocardial ischemia. MINS was an independent predictor of 30-day mortality (adjusted hazard ratio, 3.87; 95% CI, 2.96-5.08) and had the highest population-attributable risk (34.0%, 95% CI, 26.6-41.5) of the perioperative complications. Twelve hundred patients (8.0%) suffered MINS, and 58.2% of these patients would not have fulfilled the universal definition of myocardial infarction. Only 15.8% of patients with MINS experienced an ischemic symptom. Conclusion Among adults undergoing noncardiac surgery, MINS is common and associated with substantial mortality.

MyoD is required for myogenic stem cell function in adult skeletal muscle.

Abstract: To investigate the function of MyoD in adult skeletal muscle, we interbred MyoD mutant mice with mdx mice, a model for Duchenne and Becker muscular dystrophy. Mice lacking both MyoD and dystrophin displayed a marked increase in severity of myopathy leading to premature death, suggesting a role for MyoD in muscle regeneration. Examination of MyoD mutant muscle revealed elevated numbers of myogenic cells; however, myoblasts derived from these cells displayed normal differentiation potential in vitro. Following injury, MyoD mutant muscle was severely deficient in regenerative ability, and we observed a striking reduction in the in vivo proliferation of myogenic cells during regeneration. Therefore, we propose that the failure of MyoD-deficient muscle to regenerate efficiently is not caused by a reduction in numbers of satellite cells, the stem cells of adult skeletal muscle, but results from an increased propensity for stem-cell self-renewal rather than progression through the myogenic program.

Developing and Implementing a Triangulation Protocol for Qualitative Health Research

Abstract: In this article, the authors present an empirical example of triangulation in qualitative health research. The Canadian Heart Health Dissemination Project (CHHDP) involves a national examination of capacity building and dissemination undertaken within a series of provincial dissemination projects. The Project's focus is on the context, processes, and impacts of health promotion capacity building and dissemination. The authors collected qualitative data within a parallel-case study design using key informant interviews as well as document analysis. Given the range of qualitative data sets used, it is essential to triangulate the data to address completeness, convergence, and dissonance of key themes. Although one finds no shortage of admonitions in the literature that it must be done, there is little guidance with respect to operationalizing a triangulation process. Consequently, the authors are feeling their way through the process, using this opportunity to develop, implement, and reflect on a triangulation protocol.

Effects of Computer-based Clinical Decision Support Systems on Clinician Performance and Patient Outcome: A Critical Appraisal of Research

Abstract: Objective: To review the evidence from controlled trials of the effects of computer-based clinical decision support systems (CDSSs) on clinician performance and patient outcomes. Data Sources: The ...