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Science.

And that is the same physics,

medicine, nature, or time, a brain, life, the universe.

Hello, it's springtime here in the UK and there are newborn lambs all over the fields

and we're seeing the sunshine again. Glorious.

It's also been mothering Sunday and so we thought we'd talk about the science involved in having

babies.

Plus the person who can smell Parkinson's disease and a way to halve how much water plants need. I'm Katie

Haler. I'm Chris Smith and this is the Naked Scientists. The Naked

Scientists podcast is powered by UKfast.co.uk. Now first this week the brain sits cocooned behind a protective defense called the blood-brain barrier.

It's there to protect the delicate neurochemistry of the nervous system and it bars the majority of chemicals and critically drugs from entering.

Only very small molecules like caffeine, Chris's favorite molecule, can slip through

and this is a major frustration when it comes to developing treatments for diseases like

Alzheimer's because it limits the repertoire of molecules that drug designers can work with.

Unless of course you have a safe and selective way to temporarily open up the broadband barrier

and allow the right things in, which is what James Choi and his colleagues have been trying to do.

Drugs have been developed over the past several decades and they work quite well in mice and in

animal disease models but they can't get into the brain.

...