RESUMEN
BACKGROUND: No medical therapy has been shown to reduce the rate of restenosis following percutaneous transluminal coronary angioplasty. We examined the existing evidence for the use of omega-3 fatty acids in this capacity with the tool of meta-analysis. METHODS: A computerized search and a bibliographic review of published articles were performed. Abstracts were identified through journals, Index Medicus, and an unpublished listing of recent requests for fish oil for experimental use. All English-language randomized clinical trials with available reports were included in the analysis. The quality, design differences, and outcomes were evaluated for each study. RESULTS: For four studies that used angiography to define coronary restenosis, the absolute difference in restenosis rates between treatment and control groups was 13.9% (95% confidence interval [CI], 3.2% to 24.5%). Furthermore, regression analysis revealed a positive linear relationship between the dose of omega-3 fatty acids used and the absolute difference in restenosis rates (r = .99, P < .03). When three studies that used stress testing as a means of determining restenosis rates were added to the four studies that used angiography, the risk difference was 5.1% (95% CI, -3.8% to 13.9%). CONCLUSIONS: Restenosis after coronary angioplasty is reduced by supplemental fish oils, and the extent of the observed benefit may be dependent on the dose of omega-3 fatty acids used.
Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/dietoterapia , Enfermedad Coronaria/prevención & control , Aceites de Pescado/uso terapéutico , Ácidos Grasos Omega-3/uso terapéutico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Análisis de RegresiónRESUMEN
An enzyme-linked immunosorbent assay (ELISA) for insulin was developed. Anti-insulin antibody was bound to the bottom of 96-well microtiter plates. Insulin conjugated to beta-galactosidase was used as a label and methyl umbilliferyl beta-D galactoside was used as an enzyme substrate. To estimate insulin, relative fluorescence was measured with a fluorescent microtiter plate reader. Unknowns from an insulin release experiment yielded results comparable to those obtained with our enzyme-immunoassay (EIA) and a conventional radioimmunoassay (RIA). The insulin ELISA is suitable for research purposes in which samples contain solutions of physiological salts and albumin, but not for samples containing serum. The insulin ELISA is as sensitive as the insulin RIA and has several advantages over the standard insulin RIA. These include (1) avoidance of hazards and inconvenience of handling radioactivity, (2) not requiring a separate test tube for each sample, (3) stability of the enzyme-labeled insulin (greater than 18 months), (4) short time period required for the assay (less than 6 hours), and (5) the possibility of long-term storage (at least 3 months) of antibody-coated microtiter plates.