I am so at home in Dublin, more than any other city, that I feel it has always been familiar to me. It took me years to see through its soft charm to its bitter prickly kernel - which I quite like too.

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A Little Lost

The Deeper Genome: Why there is more to the human genome than meets the eye, by John Parrington, Oxford University Press, 272 pp, £18.99, ISBN: 978-0199688739 For a clinician, there is something very satisfying about situations where the findings from an obscure, now almost forgotten, scientific experiment continue to play a role in one’s day-to-day practice. For example, when I am preparing to intubate a patient, the image of a donkey being kept alive with a pair of bellows sometimes comes to mind. It is easier to intubate (pass a breathing tube through the vocal cords to artificially ventilate a patient’s lungs) if a muscle-relaxing agent such as atracurium is administered prior to the procedure. The structure of atracurium, and other similar synthetic medications, is based on that of a substance called curare, which is the toxin used in poisoned arrows by Amazonian Indians. D-tubocurarine (the scientific name for curare) was first demonstrated to have a physiological effect on large mammals in 1814, when Charles Waterton administered it to a female donkey at the Royal Veterinary College in London. Waterton was the son of a Yorkshire squire who spent twenty years travelling in the Amazonian rainforest at the start of the nineteenth century. During the latter part of this period he spent several months searching for the most potent wourali (as he called curare) available, finally sourcing his specimens from the Macushi tribe in the south of Guiana, near the border with Brazil. We now know that D-tubocurarine binds to receptors on the junctions between nerves and muscles, and interrupts the signals that lead to muscle contractions. This makes breathing, and all other voluntary movement, impossible. Therefore when the D-tubocurarine was injected into the donkey she stopped breathing, although her heart continued to beat. At this point an incision was made into her windpipe, bellows were inserted, and she was kept alive by the efforts of Waterton and his fellow vivisectionists until the effects of the toxin wore off two hours later. Animal lovers will be pleased to hear that Wouralia (as she was subsequently named) survived for a further twenty-five years at Walton Hall, near Wakefield. Back in the twenty-first century, once vecuronium has been administered to my patient, there will be a few minutes in which to insert a breathing tube through their now relaxed (and therefore open) vocal cords, and attach them to the ventilator. Another class of agents…

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