Thursday, March 22, 2012

Give Fleet Street a Plowman's Lunch of Chalk & Bread : they'll nae know the difference ....

The British media still credits Sir Alexander Fleming with far more of the penicillin glory that he ever deserves.

To them, there is no more difference between Sir Alexander's mere call for synthetically-made penicillin to apply topically as an antiseptic and Dr Martin Henry Dawson's actual use of his own naturally-grown penicillin which he then injected by needle (ie systemically) as the world's first antibiotic, than there is between chalk and cheese.

So give the good man from Fleet Street a Plowman's Lunch of Chalk and Bread --- he'll nae know the difference.

I make the actual differences to be vast as the Atlantic Ocean is between the Old World Scot Fleming and the New World Scot Dawson - and four in nature.

First, the lazy Fleming merely offered a pious hope that someone else would make his synthetic penicillin - Dawson when no pharma company would help, grew his own, in a pilot plant sized operation of 700 2 litre flasks - all this done with his incredibly tiny team of overworked amateurs.

Secondly - synthetic versus naturally grown. Here Fleming had the nearly universal support of the 1920s to 1940s medical and scientific world behind his belief that synthetic penicillin would be better, cheaper, faster  and able to make vast quantities of the medicine.

Only Dawson disagreed - fortunately a hitherto obscure company disagreed along with him - they were both proven right: we still use naturally grown penicillin, not synthetic penicillin.

Dawson is long good, but that company, PFIZER, is very much with us.

Thirdly, Fleming saw penicillin only useful as a topical application to be applied to open surface wounds - a relative rarity in peacetime - and in truth - even in wartime.

Dawson saw the most common and dangerous infections spread their colonies and toxins all through the inside of a body - ie systemically.

A really successful medicine must do the same.

Most medicine is still used internally but given by pill - but when its a life or death immediate crisis, out comes Dr Dawson's old needle to save a life.

Fourthly, Fleming saw penicillin as an antiseptic - something that is a general killer but hopefully kills more germs than it does human cells.

Dawson saw penicillin as a killer highly specific only to bacteria (this specificity is part of what we now mean by the word antibiotic).

 In fact he quickly noted penicillin only rarely killed or slowed down bacteria -- it only worked when they were, in a sense, growing and molting their skins like lobsters -- it killed the invulnerable knight when he took off his armour to pee, as it were !

Dawson knew penicillin could finally cure the incurable, invariably fatal, common heart disease of SBE not because of its virulent ability to kill bacteria per amount of medicine used - penicillin actually falls only in the middle range here in terms of potency.

He knew it would work despite that relatively low level of potency, because a medicine that only kills bacteria and rarely binds to other substances in the body is both extremely non toxic and diffuses extremely well ( the two properties are related).

The heart valves infected in SBE aren't really well supplied with an internal source of blood - ironically its a case of "blood, blood everywhere but not a drop to drink".

To penetrate the dense biofilms on the heart valves, Dawson had to saturate the entire blood supply with an amount of penicillin that would kill the patient if it was of ordinary toxicity.

 At the same time, he had to hope that its extraordinary diffusion qualities would let a little of it penetrate the valve biofilms as the penicillin molecules and blood cells raced through the heart at speeds equivalent to a human spaceship.

If you are following all this, Dawson was using penicllin-the-systemic-antibiotic rather like Fleming's old penicillin-the-topical-antiseptic --- except that he was dabbing his penicillin antiseptic internally over the heart valves.

Truly a complex (and faintly ironic) first application for the new miracle drug.

(Meanwhile the body, unfortunately because of those same extraordinary diffusion qualities, was only too able to quickly extract the penicillin out of the blood stream, where it could do good ,and into the urine where it usually did nothing useful.)

Altogether, no Sisyphus ever rolled as heavy a stone up a hill as the terminally ill Dawson did in his efforts to offer proof of concept of the viability of naturally grown penicillin used systemically to cure SBE.

But he did it and moved the most incurable heart disease into the category of the most curable - a truly extraordinary achievement.

Frankly, I think it just might be Dawson, not that other Scottish Canadian , the eugenicist Tommy Douglas, who might deserve the title of the greatest ever Canadian.

85 years after the initial discovery of penicillin, it is too much to ask of Fleet Street to grasp these easily understood, fundamental, differences between Fleming's wildly inaccurate hopes and the actual penicillin we still use today ?

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