Method and complexity in bioethics: the example of community genetics.

This article describes the need to develop a new methodology in bioethics that can consider multiple interactions, creativity and the organisation specific to complex systems. Community genetics is taken as an example of complexity in bioethics. Community genetics involves large populations and illustrates certain characteristics of complex adaptive systems which are discussed in the article.

Influence of probucol on enhanced LDL oxidation after fish oil treatment of hypertriglyceridemic patients.

The susceptibility of low-density lipoprotein (LDL) to oxidation was studied in hypertriglyceridemic men (5 with type III and 5 with type IV) at baseline on a low-saturated-fat, low-cholesterol diet, after 6 weeks of dietary supplementation with fish oil (Promega, 12 g/d), and after 6 weeks of fish oil combined with probucol (500 mg BID). The relative content of n-3 polyunsaturated fatty acids in plasma and LDL was increased during the two treatment periods, and a low alpha-tocopherol to n-3 polyunsaturated fatty acids ratio was observed. Plasma thiobarbituric acid-reactive substances (TBARS) levels were unchanged after 6 weeks of fish oil, but the ratio of lipid peroxides to the reduced triglyceride (TG) levels (MDA:TG) was significantly higher (P < .01). Addition of probucol lowered both absolute levels of TBARS (P < .01) and the MDA to TG ratio (P < .001). The susceptibility of LDL to Cu(2+)-catalyzed oxidation was evaluated over a 5-hour time course by determining TBARS formation, free amino group levels, and changes in LDL electrophoretic mobility. TBARS levels that were higher in native LDL (1.019 < d < 1.050 g/mL) after 6 weeks of fish oil than at baseline (P < .01) were reduced 52.3 +/- 11.3% by the addition of probucol (P < .001). With fish oil alone, TBARS production after exposure of LDL to Cu2+ for 5 hours was increased 17.0 +/- 5.8% compared with corresponding baseline values (P < .001), whereas a 64.1 +/- 14.3% reduction from the previous period was observed with fish oil + probucol (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)