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  • For the first time since we started making these Nobel Prize videos,

  • the Medicine Nobel Prize has got such a strong chemical content

  • that we are going to make two: one about chemistry and this one, which is about medicine.

  • And the reason why we are doing the medicine one is because it is recognizing

  • people who have discovered fundamental molecules

  • that can be used for treating disease.

  • In fact, natural products, compounds nature makes, but people isolated them, they found their

  • biological properties and it brought back a lot of memories for me.

  • The prize was divided among three people,

  • but half to two of them, the other half, to one person: Dr Youyou Tu, in China.

  • And I'm going to talk about the Chinese prize winner, because, as you'll see,

  • her discovery is pretty close to my heart

  • My colleague, Rob, our organic chemist, is going to talk about the other half of the Nobel Prize.

  • Not so much about the people as about the chemical,

  • because, as you'll hear, it's got a special meaning to him.

  • [Rob] Back as an undergraduate, in 1992, my very first project was working on a compound related to Avermectin,

  • which is one of the compounds which was discovered, and which was awarded... the discovery of which was awarded

  • the Nobel Prize this year.

  • [Brady] Avermectim?

  • [Rob] Avermectin, yeah, yeah. So, people may have heard of Ivermectin,

  • which is the... it's used as a sheep dip. So, literally, you dip the sheep in it,

  • and it gets rid of any parasites on the sheep and it works for, you know, a wide variety of things,

  • human beings, even. But, the reason I was working on it is because it doesn't work on collie dogs.

  • So, actually there are certain types- breeds of dogs which if you give them Avermectin, they'll have a heart attack and they die.

  • [Professor] The chemical that Youyou Tu discovered- and, I should say that she is the first Chinese scientist

  • to win the Nobel Prize for work done in China,

  • and, also she is one of the relatively few women that have won Nobel Prizes in science.

  • The molecule she discovered is called artemisinin, which is a very potent treatment for malaria.

  • The reason why it has this rather strange name, 'artemisinin', is because it is made as an extract-

  • or, one of the ways of obtaining it is an extract from a plant called 'Artemisia annua', which grows in China,

  • and has grown in China for as long as anybody can remember, generations.

  • It has been a traditional treatment for malaria. Now, it's very important to say that the Nobel Prize Committee

  • said that they were recognising the chemical achievement, not traditional medicine,

  • though, traditional medicine, in this case, was what led to the discovery.

  • [Rob] I was working on this compound here. Here's Avermectin. So, you can see,

  • It's quite a complicated structure. It's got this very unusual macrocyclic lactone here,

  • and the milbermycins are the same compounds, but without this sugar side chain.

  • [Brady] And that's what you were working on.

  • [Rob] Yeah, that's what we were working on. So we were taking this fermentation product. So, these all come from streptomyces' fermentation,

  • and we were breaking it down and building it back up to make a molecule which would retain the anti-parisitic properties, but didn't kill the collie dogs.

  • [Professor] The real intellectual achievement of Dr Tu was that she realised that the modern traditional treatment,

  • which was extracting the plant and then boiling the extract, seemed to produce something that was

  • not very effective. So, she went back to the ancient texts and discovered that in the old days,

  • people didn't boil it, and this led her to looking at much lower temperature extracts to see what she could find.

  • You can see the importance of this if you look at the structure of artemisinin

  • which has an oxygen-oxygen single bond, and these bonds are notoriously weak.

  • So, if you boil the solution of the molecule, it'll decompose.

  • So, people were extracting artemisinin, and then destroying it by boiling.

  • It was a really simple but clever idea that led to the discovery.

  • [Brady] That seems almost too simple for a Nobel Prize.

  • [Professor] Well, very often, Nobel Prizes are based on simple ideas. Graphene was discovered by using sticky

  • tape to remove layers of graphite. So, I think you have to be a real genius to have a really simple idea.

  • [Rob] It's like a great, big chess game. You've got to tweak and change and degrade a molecule

  • and build it back up using the rules of chemistry- the chemical reactions that are available.

  • It takes a real strategy and a real technique to understand how to do that and how to build it up.

  • So, we scanned five or six different roots to make our particular drug molecule- completely different roots,

  • but they all started from the same fermentation precursor, they all ended up with the same drug molecule.

  • [Professor] In this case- and the reason why I feel such a personal empathy is because artemisinin is a molecule

  • that I and my colleague Mike George have been working on for several years. So, you can see our video

  • on greener ways of making artemisinin which we've developed here in Nottingham.

  • And, in fact, on the day that the prize was announced, I was giving a lecture in Lisbon in which I was talking about artemisinin.

  • And, after lunch at the conference, the chairman stood up and announced the Nobel prize for artemisinin

  • and everybody burst into applause, and I felt a tiny bit of reflected glory.

  • [Rob] This, actually was the first scientific document I ever wrote. So, this is 1992, I was just a third year

  • undergraduate at the time. And, obviously when you work in a company, this is embargoed- a secret

  • but, because that's over twenty years ago now, I can disclose this compound here, although these are

  • known in the literature anyway. But, actually it was written in Word 5.1. So, it's taken me about twenty-five

  • minutes to find something which would open this document. In fact, I've lost the front page.

  • [Professor] I think there is a very important lesson in Dr Tu's Nobel Prize.

  • She is a scientist who has worked all her life in China. She has not gone to prestigious labs in other countries.

  • And, she has published her work, but not in famous journals like Nature and Science, and these other journals.

  • but it demonstrates that really original science can be recognised without looking at some of the parameters

  • that younger scientists now worry about. What is the status of the journal?- and so on.

  • So, if you are a young scientist, it is the quality of your ideas that are important, and if your ideas are really

  • good, they will be recognised.

  • So, don't broadcast this till we get back.

  • The question that I think you'll all be wanting to know

  • is how much does it weigh? What is the gold worth?

  • And so, just to answer your question,

  • I brought a balance. And that's also in my pocket.

  • It's quite a nice little balance.

  • So, here goes: weighing a Nobel Prize!

For the first time since we started making these Nobel Prize videos,

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2015年諾貝爾醫學獎--------視頻週期表 (The 2015 Nobel Prize in Medicine - Periodic Table of Videos)

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    林宜悉 發佈於 2021 年 01 月 14 日
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