"Oxidative stress" is used as the generic term describing the involve- ment of reactive oxygen species in various human diseases. The scope of such a topic is becoming increasingly wide. The recent interest in radicals such as nitric oxide and the discovery of new mechanisms such as the effect of free radicals on redox sensitive proteins and genes are enlarging our understanding of the physiological role of free radicals. Oxidative stress is involved in numerous pathological. processes such as ageing, respiratory or cardiovascular diseases, cancer, neurological pathologies such as dementia or...