[The story of oxygen (2)]

The authors, in this second part of the oxygen story, resolutely cross the borders of the biophysical field, and face the origins and becoming of life, the stages of which are synthesized in "casket" terms, unusual for surgeons: "protobionts", "procariots", "cyanobacteria", "chlorophyll", "caroteonides", "fermentation", "anaerobic glycolysis", "eucariots", "respiratory chain", "mitocondria". This is not an unconventional biological exercise, but the effort to give clinics a more legible ground, a sort of common denominator of the most different pathologies, and, among these ones, at the first place, just those of the specialistic branch, also less frequenter of biology, that is, surgery. This common denominator, the oxygen radicals represent the emerging apex of, like the peak of an iceberg, in fact, can be only investigated through an exasperated "philogenetic" recovering. Such process of "archaeology" seems to be the only suitable to supply us the cipher-key of the ambiguous, shifty character of oxygen, and entrust us with a cultural patrimony being unique as it is spendable in an immediate clinical future.