ABOUT THE SPEAKER
Richard Weller - Dermatologist
Dermatologist Richard Weller wants to know: Why are Scots so sick?

Why you should listen

Edinburgh-native Richard Weller was studying medicine in Australia when something suddenly struck him as odd: Why are the Scots so sick? Australians suffer from heart disease at one-third the rate that Britons do, with lower death rates from heart attacks and heart failure, and fewer strokes overall. When Weller looked into it, this wasn't unique to Australia and England: In fact, there are wide gaps in mortality even within the UK, a gradient which maps roughly ... geographically? A five-degree change in latitude -- between London and Edinburg, for example -- shows a nearly 20 percent higher rate of mortality. Weller and his team have been working ever since to crack this mysterious gap, and most recently their research shows it may be related to exposure to sunlight. Nitric oxide (NO), a chemical transmitter produced by the skin and stored in great reserves, is released by exposure to UV rays, and this in turn is very important to cardiovascular health.

Weller is a senior lecturer in Dermatology at the University of Edinburgh. His two areas of study are the role of NO in human skin physiology and the role of skin barrier function deficiencies in atopic disease.

More profile about the speaker
Richard Weller | Speaker | TED.com
TEDxGlasgow

Richard Weller: Could the sun be good for your heart?

Richard Weller: Pode o sol ser bo para o teu corazón?

Filmed:
1,175,703 views

Os nosos corpos reciben vitamina D do sol, pero como suxire o dermatólogo Richard Weller, a luz solar pode producir tamén outro beneficio sorprendente. Novas investigacións do seu equipo amosan que o óxido nítrico, un transmisor químico almacenado en grandes reservas na pel, pode ser liberado grazas á luz ultravioleta, producindo grandes beneficios na presión sanguínea e no sistema cardiovascular. Que significa isto? Pois podería chegar a explicar por que os escoceses enferman máis que os australianos...
- Dermatologist
Dermatologist Richard Weller wants to know: Why are Scots so sick? Full bio

Double-click the English transcript below to play the video.

00:16
So, before I became a dermatologist,
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Antes de facerme dermatólogo,
comecei na medicina xeral,
00:18
I started in general medicine,
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como fan moitos dermatólogos
en Gran Bretaña.
00:21
as most dermatologists do in Britain.
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00:23
At the end of that time, I went off to Australia,
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Ao rematar, fun a Australia,
00:25
about 20 years ago.
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hai case vinte anos.
00:27
What you learn when you go to Australia
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Cando marchas a Australia
00:29
is the Australians are very competitive.
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aprendes que os australianos
son moi competitivos.
00:32
And they are not magnanimous in victory.
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E non son magnánimos nas vitorias.
00:34
And that happened a lot:
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E iso pasaba moito:
00:36
"You pommies, you can't play cricket, rugby."
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"Ingleses, non sabedes xogar
ao cricket, rugby...".
00:38
I could accept that.
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Podía aceptar iso.
00:40
But moving into work --
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No relacionado ao traballo,
00:43
and we have each week what's called a journal club,
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temos semanalmente
un club de lectura,
00:45
when you'd sit down with the other doctors
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onde sentas cos outros médicos
00:48
and you'd study a scientific paper
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e estudas unha publicación científica
00:50
in relation to medicine.
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que teña relación coa medicina.
00:52
And after week one, it was about cardiovascular mortality,
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O segundo encontro foi
sobre a mortalidade cardiovascular,
00:54
a dry subject -- how many people die of heart disease,
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un tema complicado.
As mortes por enfermidades cardíacas,
00:58
what the rates are.
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cales son as taxas.
01:00
And they were competitive about this:
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E eran competitivos sobre isto:
01:01
"You pommies, your rates of heart disease are shocking."
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"Ingleses, as vosas taxas
de cardiopatías son tremendas."
01:05
And of course, they were right.
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E certamente tiñan razón.
01:06
Australians have about a third less heart disease than we do --
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Os australianos teñen un terzo menos
de cardiopatías ca nós
01:10
less deaths from heart attacks, heart failure, less strokes --
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--menos mortes por ataques ao corazón,
por insuficiencias cardíacas ou infartos.
01:14
they're generally a healthier bunch.
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Adoitan ser máis sans.
01:16
And of course they said this was because of
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E claro, dicían que isto era
pola súa superior integridade moral
01:18
their fine moral standing, their exercise,
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01:20
because they're Australians and we're weedy pommies, and so on.
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porque eles son australianos
e nós frouxos inglesiños.
01:24
But it's not just Australia that has better health than Britain.
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Pero non é só que teñan mellor saúde
ca Gran Bretaña.
01:29
Within Britain, there is a gradient of health --
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En Gran Bretaña hai
un gradiente de saúde,
01:33
and this is what's called standardized mortality,
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isto chámase mortalidade estandarizada,
01:35
basically your chances of dying.
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é dicir, as probabilidades de morrer.
01:37
This is looking at data from the paper about 20 years ago,
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Estes son datos dos xornais
de hai vinte anos,
01:40
but it's true today.
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mais segue sendo certo hoxe.
01:42
Comparing your rates of dying 50 degrees north --
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Se comparamosas taxas de mortalidade
a 50 graos norte
01:45
that's the South, that's London and places --
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--esa frecha sinala o sur,
Londres e contorna--
01:47
by latitude, and 55 degrees --
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e a 55º norte,
01:50
the bad news is that's here, Glasgow.
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a mala noticia é que Glasgow
é isto de aquí.
01:53
I'm from Edinburgh. Worse news, that's even Edinburgh.
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Eu son de Edimburgo.
Peores novas aínda en Edimburgo.
01:55
(Laughter)
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(Risos)
02:00
So what accounts for this horrible space here
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Entón, que é o que pasa
neste terrible espazo,
02:03
between us up here in southern Scotland
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aquí entre nós, no sur de Escocia,
02:05
and the South?
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e o sur?
02:06
Now, we know about smoking,
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Xa sabemos o dos fumadores,
02:08
deep-fried Mars bars, chips -- the Glasgow diet.
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as barriñas Mars fritidas, as patacas...
a dieta de Glasgow.
02:10
All of these things.
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Todo iso.
02:12
But this graph is after taking into account
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Mais esta gráfica xa ten en conta,
02:14
all of these known risk factors.
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todos estes factores de risco coñecidos.
02:16
This is after accounting for smoking, social class, diet,
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Isto xa ten en conta
fumadores, clase social, dieta,
02:20
all those other known risk factors.
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todos eses factores de risco coñecidos.
02:22
We are left with this missing space
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Quédanos este espazo perdido,
02:24
of increased deaths the further north you go.
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de mortes crecentes
canto máis vaias ao norte.
02:28
Now, sunlight, of course, comes into this.
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A luz do sol, por suposto, inflúe.
02:31
And vitamin D has had a great deal of press,
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A vitamina D tivo moi mala prensa,
02:33
and a lot of people get concerned about it.
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e moita xente preocúpase por ela.
02:35
And we need vitamin D. It's now a requirement that children have a certain amount.
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E precisamos a vitamina D.
Agora é unha obriga que os nenos
teñan unha cantidade concreta.
02:39
My grandmother grew up in Glasgow,
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Miña avoa medrou en Glasgow,
alá polo 1920 e os anos 30,
02:41
back in the 1920s and '30s when rickets was a real problem
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cando o raquitismo era un gran problema
02:45
and cod liver oil was brought in.
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e chegou o aceite de fígado de bacallau.
02:47
And that really prevented the rickets that used to be common in this city.
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Iso solucionou o raquitismo que
era tan común nesta cidade.
02:51
And I as a child was fed cod liver oil by my grandmother.
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A min, de pequeno, miña avoa
fíxome tomar este aceite.
02:55
I distinctly -- nobody forgets cod liver oil.
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Obviamente... ninguén esquece
nunca o aceite de fígado de bacallau.
02:58
But an association: The higher people's blood levels of vitamin D are,
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Unha cuestión: canto máis altos
son os niveis de vitamina D na xente,
03:03
the less heart disease they have, the less cancer.
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menos cardiopatías e menos cancros teñen.
03:06
There seems to be a lot of data suggesting that vitamin D is very good for you.
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Hai moitas estatísticas que indican
que a vitamina D é boa para nós.
03:10
And it is, to prevent rickets and so on.
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E así é, para previr raquitismo e iso.
03:12
But if you give people vitamin D supplements,
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Pero se lle dás á xente
suplementos de vitamina D,
03:15
you don't change that high rate of heart disease.
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non cambias esa alta taxa de cardiopatías.
03:18
And the evidence for it preventing cancers is not yet great.
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E as probas de que preveña o cancro
aínda non son definitivas.
03:22
So what I'm going to suggest is that vitamin D is not the only story in town.
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Entón o que vou suxerir é que a vitamina D
non é o único importante aquí.
03:27
It's not the only reason preventing heart disease.
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Non é a única razón
que prevén unha cardiopatía.
03:30
High vitamin D levels, I think, are a marker for sunlight exposure,
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Niveis altos de vitamina D, penso eu,
son indicadores da exposición á luz solar,
03:35
and sunlight exposure, in methods I'm going to show,
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e a exposición á luz solar,
nos mecanismos que vou ensinar,
é boa para as enfermidades do corazón.
03:38
is good for heart disease.
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03:40
Anyway, I came back from Australia,
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En calquera caso, volvín de Australia
03:42
and despite the obvious risks to my health, I moved to Aberdeen.
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e, a pesar dos obvios riscos
para a miña saúde, mudeime a Aberdeen,
03:46
(Laughter)
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(Risos)
03:48
Now, in Aberdeen, I started my dermatology training.
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Agora, en Aberdeen, comecei
a miña formación como dermatólogo.
03:51
But I also became interested in research,
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Pero tamén me
interesei na investigación,
03:53
and in particular I became interested in this substance, nitric oxide.
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e sobre todo nesta substancia,
o óxido nítrico (NO).
03:56
Now these three guys up here,
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Estes tres tipos de aquí,
Furchfott, Ignarro e Murad,
03:58
Furchgott, Ignarro and Murad,
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03:59
won the Nobel Prize for medicine back in 1998.
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gañaron o Premio Nobel
de Medicina en 1998.
04:03
And they were the first people to describe
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Foron as primeiras persoas en describir
04:05
this new chemical transmitter, nitric oxide.
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este novo transmisor químico,
o óxido nítrico.
04:08
What nitric oxide does is it dilates blood vessels,
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O óxido nítrico (NO)
dilata os vasos sanguíneos,
04:11
so it lowers your blood pressure.
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así baixa a túa presión sanguínea.
04:13
It also dilates the coronary arteries, so it stops angina.
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Tamén dilata as arterias coronarias,
co que detén as anxinas.
E o que é máis impresionante del
04:17
And what was remarkable about it
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04:19
was in the past when we think of chemical messengers within the body,
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é que no pasado, cando pensabamos en
mensaxeiros químicos dentro do corpo,
04:23
we thought of complicated things like estrogen and insulin,
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pensabamos en cousas complicadas
como estróxeno e insulina,
04:26
or nerve transmission.
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ou a transmisión nerviosa.
04:27
Very complex processes with very complex chemicals
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Procesos moi complexos con
substancias químicas moi complexas
04:31
that fit into very complex receptors.
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que encaixan en receptores moi complexos.
04:33
And here's this incredibly simple molecule,
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E velaquí esta molécula
incriblemente simple,
04:35
a nitrogen and an oxygen that are stuck together,
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un nitróxeno e un osíxeno
pegados,
04:39
and yet these are hugely important for [unclear] our low blood pressure,
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que son tamén moi importantes
para manter baixa a presión arterial,
04:43
for neurotransmission, for many, many things,
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para a neurotransmisión e
para outras moitas cousas,
04:46
but particularly cardiovascular health.
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especialmente para
a saúde cardiovascular.
04:49
And I started doing research, and we found, very excitingly,
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Comecei a investigar e descubrimos,
de xeito moi emocionante,
04:53
that the skin produces nitric oxide.
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que a pel produce óxido nítrico.
04:55
So it's not just in the cardiovascular system it arises.
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Así que non xorde só
no sistema cardiovascular.
04:58
It arises in the skin.
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Xorde na pel.
05:00
Well, having found that and published that,
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Despois de descubrilo e publicalo
05:02
I thought, well, what's it doing?
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pensei, que é o que fai?
05:04
How do you have low blood pressure in your skin?
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Como tes baixa presión arterial na pel?
05:05
It's not the heart. What do you do?
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Non é o corazón. Que facemos logo?
05:07
So I went off to the States, as many people do if they're going to do research,
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Marchei aos Estados Unidos, como fai
moita xente que quere investigar,
05:11
and I spent a few years in Pittsburgh. This is Pittsburgh.
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e pasei uns poucos anos
en Pittsburgh. Velaí Pittsburgh.
05:15
And I was interested in these really complex systems.
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Interesábanme estes
sistemas tan complexos.
05:18
We thought that maybe nitric oxide affected cell death,
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Pensabamos que o óxido nítrico
podía afectar á morte das células,
05:22
and how cells survive, and their resistance to other things.
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a como sobreviven e
á súa resistencia a máis cousas.
05:24
And I first off started work in cell culture, growing cells,
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Entón comecei a traballar
no cultivo de células,
05:28
and then I was using knockout mouse models --
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e usei modelos de rato "knockout"
05:30
mice that couldn't make the gene.
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--ratos con xenes desactivados--
05:32
We worked out a mechanism, which -- NO was helping cells survive.
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Traballamos nun mecanismo en que o NO
lles axudaba ás células a sobrevivir.
05:36
And I then moved back to Edinburgh.
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Daquela mudeime outra vez a Edimburgo.
Alí o animal de laboratorio que
usamos foi o estudante de medicina
05:40
And in Edinburgh, the experimental animal we use is the medical student.
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05:43
It's a species close to human,
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É unha especie próxima ao ser humano,
05:45
with several advantages over mice:
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con moitas vantaxes sobre os ratos:
05:47
They're free, you don't shave them, they feed themselves,
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son libres, non os tes que
afeitar nin alimentar,
e ninguén se manifesta
diante do despacho dicindo
05:50
and nobody pickets your office saying,
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05:52
"Save the lab medical student."
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"Salva ao estudante de
medicina de laboratorio".
05:55
So they're really an ideal model.
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Polo que son un
coello de indias ideal.
05:58
But what we found
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Atopamos que non podiamos reproducir
en persoas os datos recollidos dos ratos.
06:00
was that we couldn't reproduce in man the data we had shown in mice.
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06:04
It seemed we couldn't turn off the production
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Parecía que non podiamos frear a xeración
do óxido nítrico na pel humana.
06:08
of nitric oxide in the skin of humans.
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06:11
We put on creams that blocked the enzyme that made it,
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Puxémoslles cremas para bloquear o encima
que o xeraba, inxectámoslles cousas.
06:13
we injected things. We couldn't turn off the nitric oxide.
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Non podiamos parar
o óxido nítrico.
06:18
And the reason for this, it turned out, after two or three years' work,
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A razón era --descubrímolo despois
de dous ou tres anos de traballo--
06:21
was that in the skin we have huge stores
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que na pel temos uns enormes almacéns,
06:25
not of nitric oxide, because nitric oxide is a gas,
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non de óxido nítrico, que é un gas,
06:28
and it's released -- (Poof!) -- and in a few seconds it's away,
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e logo de liberado... puf!
Nuns segundos desaparece,
06:31
but it can be turned into these forms of nitric oxide --
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mais pode encontrarse noutras formas:
06:35
nitrate, NO3; nitrite, NO2; nitrosothiols.
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nitrato (NO3), nitrito (NO2), tionitritos.
06:38
And these are more stable,
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Estes son máis estables,
06:40
and your skin has got really large stores of NO.
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e a túa pel ten enormes almacéns de NO.
06:44
And we then thought to ourselves, with those big stores,
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Despois pensamos, se estes almacéns,
06:47
I wonder if sunlight might activate those stores
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poderían ser activados pola luz solar
para liberar o óxido desde a pel,
06:50
and release them from the skin,
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06:52
where the stores are about 10 times as big as what's in the circulation.
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onde os almacéns son dez veces máis
grandes do que son na circulación.
06:55
Could the sun activate those stores into the circulation,
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Podería o sol activar estes almacéns
cara á circulación,
06:58
and there in the circulation do its good things for your cardiovascular system?
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e aí, na circulación, facer cousas boas
para o sistema cardiovascular?
07:03
Well, I'm an experimental dermatologist,
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Ben, eu son dermatólogo experimental,
07:06
so what we did was we thought
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e o que fixemos foi pensar que debiamos
expoñer os coellos de indias á luz solar.
07:07
we'd have to expose our experimental animals to sunlight.
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07:11
And so what we did was we took a bunch of volunteers
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Así que collemos unha
serie de voluntarios
07:15
and we exposed them to ultraviolet light.
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e expuxémolos á luz ultravioleta.
07:17
So these are kind of sunlamps.
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Son unha especie de
lámpadas solares.
07:19
Now, what we were careful to do was,
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Agora ben, fomos
coidadosos co seguinte,
07:22
vitamin D is made by ultraviolet B rays
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a vitamina D está feita
de raios ultravioleta B
07:25
and we wanted to separate our story from the vitamin D story.
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e queriamos separar o noso estudo
do estudo da vitamina D
07:29
So we used ultraviolet A, which doesn't make vitamin D.
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Así que usamos ultravioleta A,
que non xera vitamina D.
07:33
When we put people under a lamp
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Cando puxemos xente baixo a lámpada
07:35
for the equivalent of about 30 minutes of sunshine in summer in Edinburgh,
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durante o equivalente a 30 minutos
de sol no verán en Edimburgo,
07:40
what we produced was, we produced a rise
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o que producimos foi un crecemento
na circulación de óxido nítrico.
07:42
in circulating nitric oxide.
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07:44
So we put patients with these subjects under the UV,
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Entón, ao poñer estes suxeitos
baixo a luz ultravioleta,
07:47
and their NO levels do go up,
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os seus niveis de NO medraron,
07:50
and their blood pressure goes down.
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e a súa presión arterial diminuíu.
07:52
Not by much, as an individual level,
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Non moito, a nivel individual,
07:54
but enough at a population level
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pero abondo a nivel poboacional,
07:57
to shift the rates of heart disease in a whole population.
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como para cambiar as taxas de enfermidades
cardíacas en toda a poboación.
08:00
And when we shone UV at them,
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Cando lles diriximos raios ultravioleta,
08:03
or when we warmed them up to the same level as the lamps,
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ou cando os quentabamos ao mesmo
nivel que as propias lámpadas,
08:06
but didn't actually let the rays hit the skin, this didn't happen.
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impedindo que os raios
acadaran a pel, iso non sucedía.
08:10
So this seems to be a feature of ultraviolet rays hitting the skin.
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Parece ser unha característica dos raios
ultravioleta cando acadan a pel.
08:14
Now, we're still collecting data.
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Agora aínda estamos recollendo datos.
08:15
A few good things here:
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Algunhas cousas boas:
08:17
This appeared to be more marked in older people.
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O efecto é máis pronunciado
nas persoas maiores.
08:20
I'm not sure exactly how much.
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Non sei canto exactamente.
08:22
One of the subjects here was my mother-in-law,
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Aquí, un dos suxeitos foi miña sogra,
08:23
and clearly I do not know her age.
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de quen, obviamente, non sei a idade.
08:26
But certainly in people older than my wife,
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Mais certamente en xente
maior que a miña muller,
08:30
this appears to be a more marked effect.
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este parece ser un efecto
máis pronunciado.
Outra cousa que debo mencionar
08:33
And the other thing I should mention
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08:34
was there was no change in vitamin D.
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é que non houbo cambios na vitamina D.
08:36
This is separate from vitamin D.
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Isto é independente da vitamina D.
Así que a vitamina D é boa para ti:
08:38
So vitamin D is good for you -- it stops rickets,
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frea o raquitismo, prevén
o metabolismo do calcio, etc.
08:40
it prevents calcium metabolism, important stuff.
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08:42
But this is a separate mechanism from vitamin D.
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Mais isto é un mecanismo
independente da vitamina D.
08:45
Now, one of the problems with looking at blood pressure
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Un problema coa presión arterial
é que o corpo fai todo o que precisa,
08:48
is your body does everything it can
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para manter estable a presión arterial.
08:49
to keep your blood pressure at the same place.
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08:51
If your leg is chopped off and you lose blood,
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Se che cortan a perna
e perdes sangue,
08:52
your body will clamp down, increase the heart rate,
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o corpo toma medida:,
incrementa o ritmo do corazón,
08:55
do everything it can to keep your blood pressure up.
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fai todo o posible para
manter a presión arterial.
08:58
That is an absolutely fundamental physiological principle.
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É un principio fisiolóxico fundamental.
09:01
So what we've next done
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O que fixemos despois
09:02
is we've moved on to looking at blood vessel dilatation.
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foi comezar a observar
a dilatación dos vasos sanguíneos.
09:06
So we've measured -- this is again,
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Medimos
--fíxense que sen cola e sen pelo,
este é un estudante de medicina.
09:08
notice no tail and hairless, this is a medical student.
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(Risos)
No brazo, pódese medir o fluxo sanguíneo,
09:13
In the arm, you can measure blood flow in the arm
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09:15
by how much it swells up as some blood flows into it.
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calculando o que este incha
cando o sangue o atravesa.
09:19
And what we've shown is that doing a sham irradiation --
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Demostramos que facendo
unha irradiación simulada,
nesta liña máis grosa,
09:22
this is the thick line here --
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09:24
this is shining UV on the arm so it warms up
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radiando raios ultravioleta
no brazo para quentalo,
09:26
but keeping it covered so the rays don't hit the skin.
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manténdoo cuberto para que
os raios non acaden a pel,
09:29
There is no change in blood flow, in dilatation of the blood vessels.
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non hai cambio no fluxo sanguíneo,
na dilatación dos vasos sanguíneos.
09:33
But the active irradiation,
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Pola contra, a irradiación activa,
09:35
during the UV and for an hour after it,
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durante a radiación ultravioleta e
ata unha hora despois ,
09:38
there is dilation of the blood vessels.
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provoca dilatación dos vasos sanguíneos.
09:40
This is the mechanism by which you lower blood pressure,
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2600
Este é o mecanismo polo
que a presión arterial baixa,
09:43
by which you dilate the coronary arteries also,
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polo que se dilatan
as arterias coronarias,
para que o corazón
subministre sangue.
09:45
to let the blood be supplied with the heart.
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09:47
So here, further data that ultraviolet -- that's sunlight --
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Aquí hai máis datos sobre
os raios ultravioleta (UV), a luz solar,
09:51
has benefits on the blood flow and the cardiovascular system.
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que ten beneficios no fluxo sanguíneo
e no sistema cardiovascular.
09:56
So we thought we'd just kind of model --
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Pensamos que conseguiramos un modelo,
09:58
Different amounts of UV hit different parts of the Earth at different times of year,
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diferentes cantidades de UV acadan a
Terra en diferentes momentos do ano,
así pódense activar os almacéns
de óxido nítrico,
10:05
so you can actually work out those stores of nitric oxide --
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10:09
the nitrates, nitrites, nitrosothiols in the skin --
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os nitratos, nitritos,
tionitritos na pel...
10:11
cleave to release NO.
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descompostos para liberar NO.
10:14
Different wavelengths of light have different activities of doing that.
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Diferentes lonxitudes de onda da luz
teñen diferentes mecanismos para facelo.
10:18
So you can look at the wavelengths of light that do that.
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Pódese ver a lonxitude
de onda da luz que o fai.
10:20
And you can look -- So, if you live on the equator, the sun comes straight overhead,
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Pódese observar que se vives no ecuador,
o sol chega xusto sobre a cabeza,
10:24
it comes through a very thin bit of atmosphere.
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atravesa unha capa fina de atmosfera.
10:25
In winter or summer, it's the same amount of light.
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A cantidade de luz é a mesma
no inverno e no verán.
10:28
If you live up here, in summer
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Se vives aquí no norte,
no verán o sol chega directamente,
10:30
the sun is coming fairly directly down,
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2656
10:33
but in winter it's coming through a huge amount of atmosphere,
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pero no inverno atravesa unha
gran cantidade de atmosfera,
10:36
and much of the ultraviolet is weeded out,
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e moitos dos raios ultravioleta desfanse,
10:40
and the range of wavelengths that hit the Earth
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2352
e o rango das lonxitudes de onda
que golpean a Terra
10:42
are different from summer to winter.
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2328
é diferente no verán e no inverno.
10:44
So what you can do is you can multiply those data
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Entón podes multiplicar estes datos
10:46
by the NO that's released
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1993
polo NO que se libera
10:48
and you can calculate how much nitric oxide
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3184
e podes calcular canto
10:51
would be released from the skin into the circulation.
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3169
sería liberado pola pel na circulación.
10:55
Now, if you're on the equator here --
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2000
Agora ben, se vives no ecuador,
10:57
that's these two lines here, the red line and the purple line --
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nestas dúas liñas de aquí, as liñas
vermella e violeta,
11:00
the amount of nitric oxide that's released is the area under the curve,
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4397
a cantidade de óxido nítrico
que se libera é a área baixo a curva,
11:04
it's the area in this space here.
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a área neste espazo de aquí.
11:06
So if you're on the equator, December or June,
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Entón se estás no ecuador,
en decembro ou en xuño,
11:09
you've got masses of NO being released from the skin.
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3256
libéranse grandes cantidades de NO da pel.
11:12
So Ventura is in southern California.
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2464
Na cidade de Ventura,
no sur de California, o verán pode ser
tal e como é no ecuador.
11:15
In summer, you might as well be at the equator.
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11:17
It's great. Lots of NO is released.
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2056
É xenial. Libérase un montón de NO.
11:19
Ventura mid-winter, well, there's still a decent amount.
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3943
Ventura, na metade do inverno,
hai aínda unha boa cantidade.
11:23
Edinburgh in summer, the area beneath the curve is pretty good,
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3961
En Edimburgo, no verán, a área
baixo a curva é bastante boa,
11:27
but Edinburgh in winter, the amount of NO that can be released
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4215
mais Edimburgo no inverno, a cantidade
de NO que pode ser liberada
11:31
is next to nothing, tiny amounts.
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3858
é case nula, pequenas cantidades.
11:35
So what do we think?
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679693
1805
Entón que pensamos?
11:37
We're still working at this story,
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1592
Seguimos traballando no estudo,
11:38
we're still developing it, we're still expanding it.
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1912
estamos desenvolvéndoo
e expandíndoo.
11:40
We think it's very important.
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Pensamos que é moi importante.
11:42
We think it probably accounts for a lot of the north-south health divide within Britain,
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3593
É probable que explique o gradiente de
saúde entre o norte-sur do Reino Unido,
11:46
It's of relevance to us.
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1631
É relevante para nós.
11:47
We think that the skin --
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Pensamos que a pel,
11:49
well, we know that the skin has got very large stores
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2888
sabemos que a pel ten grandes almacéns
de óxido nítrico baixo formas diversas.
11:52
of nitric oxide as these various other forms.
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2224
11:54
We suspect a lot of these come from diet,
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Sospeitamos que isto procede da dieta,
11:56
green leafy vegetables, beetroot, lettuce
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vexetais de folla verde,
remolacha e leituga,
11:58
has a lot of these nitric oxides that we think go to the skin.
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3320
teñen moitos destes óxidos de nitróxeno
que pensamos que van á pel.
12:02
We think they're then stored in the skin,
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Pensamos que están almacenados na pel,
12:04
and we think the sunlight releases this
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e pensamos que a luz solar os libera,
12:06
where it has generally beneficial effects.
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onde teñen, polo xeral,
efectos beneficiosos.
12:09
And this is ongoing work, but dermatologists --
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Isto é un traballo en curso,
pero os dermatólogos,
12:11
I mean, I'm a dermatologist.
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é dicir, eu son un dermatólogo.
O meu traballo diario é dicirlle á xente:
12:13
My day job is saying to people, "You've got skin cancer,
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"Tes cancro de pel por culpa
da luz solar, non te poñas ao sol".
12:15
it's caused by sunlight, don't go in the sun."
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1880
12:17
I actually think a far more important message
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Penso que unha mensaxe
realmente máis importante
12:20
is that there are benefits as well as risks to sunlight.
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é que a luz solar produce beneficios
e riscos.
12:23
Yes, sunlight is the major alterable risk factor for skin cancer,
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5753
Si, a luz solar é o principal factor
de risco modificable de cancro de pel,
12:29
but deaths from heart disease are a hundred times higher
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pero hai centos de veces máis mortes
por enfermidades do corazón
12:32
than deaths from skin cancer.
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1952
ca por cancro de pel.
12:34
And I think that we need to be more aware of,
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Creo que necesitamos ser
máis conscientes disto,
12:37
and we need to find the risk-benefit ratio.
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e atopar
a relación de risco-beneficio.
12:39
How much sunlight is safe,
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Canta luz solar é segura,
12:40
and how can we finesse this best for our general health?
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e como podemos axustar mellor isto
para a nosa saúde xeral?
12:44
So, thank you very much indeed.
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Moitas grazas, de verdade.
12:47
(Applause)
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(Aplausos)
[Recoñecementos]

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ABOUT THE SPEAKER
Richard Weller - Dermatologist
Dermatologist Richard Weller wants to know: Why are Scots so sick?

Why you should listen

Edinburgh-native Richard Weller was studying medicine in Australia when something suddenly struck him as odd: Why are the Scots so sick? Australians suffer from heart disease at one-third the rate that Britons do, with lower death rates from heart attacks and heart failure, and fewer strokes overall. When Weller looked into it, this wasn't unique to Australia and England: In fact, there are wide gaps in mortality even within the UK, a gradient which maps roughly ... geographically? A five-degree change in latitude -- between London and Edinburg, for example -- shows a nearly 20 percent higher rate of mortality. Weller and his team have been working ever since to crack this mysterious gap, and most recently their research shows it may be related to exposure to sunlight. Nitric oxide (NO), a chemical transmitter produced by the skin and stored in great reserves, is released by exposure to UV rays, and this in turn is very important to cardiovascular health.

Weller is a senior lecturer in Dermatology at the University of Edinburgh. His two areas of study are the role of NO in human skin physiology and the role of skin barrier function deficiencies in atopic disease.

More profile about the speaker
Richard Weller | Speaker | TED.com