ABSTRACT
A definitive understanding of the role of dietary lipids in determining cardioprotection (or cardiodetriment) has been elusive. Randomized trial findings have been variable and sex specificity of dietary interventions has not been determined. In this investigation the sex-selective cardiac functional effects of three diets enriched by omega-3 or omega-6 polyunsaturated fatty acids (PUFA) or enriched to an equivalent extent in saturated fatty acid components were examined in rats after an 8-wk treatment period. In females the myocardial membrane omega-6:omega-3 PUFA ratio was twofold higher than males in the omega-6 diet replacement group. In diets specified to be high in omega-3 PUFA or in saturated fat, this sex difference was not apparent. Isolated cardiomyocyte and heart Langendorff perfusion experiments were performed, and molecular measures of cell viability were assessed. Under basal conditions the contractile performance of omega-6 fed female cardiomyocytes and hearts was reduced compared with males. Omega-6 fed females exhibited impaired systolic resilience after ischemic insult. This response was associated with increased postischemia necrotic cell damage evaluated by coronary lactate dehydrogenase during reperfusion in omega-6 fed females. Cardiac and myocyte functional parameters were not different between omega-3 and saturated fat dietary groups and within these groups there were no discernible sex differences. Our data provide evidence at both the cardiac and cardiomyocyte levels that dietary saturated fatty acid intake replacement with an omega-6 (but not omega-3) enriched diet has selective adverse cardiac effect in females. This finding has potential relevance in relation to women, cardiac risk, and dietary management.
Subject(s)
Fatty Acids, Omega-3/pharmacology , Fatty Acids, Omega-6/pharmacology , Fatty Acids/pharmacology , Heart/drug effects , Myocardial Ischemia/metabolism , Myocardium/metabolism , Myocytes, Cardiac/drug effects , Recovery of Function/drug effects , Animals , Calcium/metabolism , Cell Membrane/metabolism , Cell Survival , Dietary Supplements , Fatty Acids, Omega-3/metabolism , Fatty Acids, Omega-6/metabolism , Female , Heart/physiopathology , Immunoblotting , Isolated Heart Preparation , L-Lactate Dehydrogenase/drug effects , L-Lactate Dehydrogenase/metabolism , Male , Myocardial Contraction/drug effects , Myocardial Ischemia/physiopathology , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/physiopathology , Myocardium/pathology , Myocytes, Cardiac/metabolism , Necrosis , RatsABSTRACT
BACKGROUND: The use of handheld computers in medicine has increased in the last decade, they are now used in a variety of clinical settings. There is an underlying assumption that electronic data capture is more accurate that paper-based data methods have been rarely tested. This report documents a study to compare the accuracy of hand held computer data capture versus more traditional paper-based methods. METHODS: Clinical nurses involved in a randomised controlled trial collected patient information on a hand held computer in parallel with a paper-based data form. Both sets of data were entered into an access database and the hand held computer data compared to the paper-based data for discrepancies. RESULTS: Error rates from the handheld computers were 67.5 error per 1000 fields, compared to the accepted error rate of 10 per 10,000 field for paper-based double data entry. Error rates were highest in field containing a default value. CONCLUSION: While popular with staff, unacceptable high error rates occurred with hand held computers. Training and ongoing monitoring are needed if hand held computers are to be used for clinical data collection.
