Science at Cambridge: Medicine

6D Katy Crooks 1
UniversityPRACTISING THE SCIENCE OF MEDICINE

“There is nothing – nothing at all – that compares with the exhilaration of discovery, of being the first person on the planet to see something new and understand what it means.”
Frances Ashcroft, Professor of Physiology at the University of Oxford

It’s 9am. Having battled my way through the swathes of cyclists coming into Cambridge unscathed (a daily triumph), I make my way into the physiology department, don a lab coat and start the day.

The project I am working on is looking at mouse hearts which beat unusually. The technique is pretty fiddly, it involves inserting a minute glass electrode into one of the cells in the heart. We then measure the changes in potential difference between the inside and outside of the cell – these are the changes in electrical potential that underlie contraction. By understanding their electrical activity, the hope is that the results will further our understanding of the human heart, and what happens when things go wrong.

I head up to the lab and make the electrodes we will use that day. It involves taking a small hollow glass rod, and using an electrode puller to heat and stretch it until it breaks. The result is a tip which is narrower than the wavelength of light, sharp enough to pierce but not disrupt the membrane of a single cell. Using a tapered pipette, I fill each of them with a high concentration of potassium chloride to allow the movement of current through them during the experiments. I work meticulously – one knock of the tip or bubble in the electrode will render my carefully made electrode useless.

It was in my first term at Cambridge that I first studied the physiology of excitable tissues. In the midst of a term full of vast quantities of anatomical terms and complex biochemical pathways, the mathematical rationale and unifying concepts of electrophysiology were refreshingly intuitive. The concepts and techniques baffled me to start with, and still do to some degree. But I loved it because once you understood it, you never lost that understanding – and it changed the way you thought.

While I finish the electrodes, one of the others in our team dissects and cannulates the aorta of the heart we are to use. I load it onto the rig, start perfusing it, and the tissue recovers from the shock of being placed in ice and starts beating again, the different parts contracting in sequence. It’s a strange and miraculous sight. We’re working in a tiny and completely chaotic room – not as glamorous as I once pictured medical research. Forget shiny white surfaces and high tech equipment – the rig I work at is a maze of adjusters and wires patching together an assortment of slightly bizarre looking bits of apparatus and enclosed in a massive wire box to eliminate electrical noise.

We work all day, interrupted only for a lecture on calcium homeostasis and a rushed lunch. The preparation is temperamental, with the heart occasionally moving and dislodging the electrode. Finally however, we get a beautiful train of classic ventricular action potentials. I look at the trace, and see the very same thing I studied in first year – but this time I recorded it myself.

It’s a wonderful feeling, and on my cycle back to Murray Edwards through the dark streets of Cambridge I think over my time here. Medicine at Cambridge has been quite full on. A lot of the time, you feel more like a natural scientist – it is easy for the clinical applications to get lost in the rigorous training in the medical sciences. It has been hard work, and I can count the number of patients I have seen on one hand. Though difficult at times, the firm grounding in science and the opportunities at Cambridge make me so grateful for being here. It’s not just the facts you learn which prepare you for being a doctor, but starting your medical training with the mentality of a scientist teaches you to think analytically and logically. I feel ready to get on the wards next year and apply what I have learnt in this mindset. But for now, I will enjoy seeking discovery as Frances Ashcroft describes. I do not expect this year to reveal anything which will radicalise the way we view the heart – but I do know that what I am seeing, if I do it well, is first hand and real. I could contribute knowledge, and that’s a privilege.

Katy Crooks
Undergraduate

School Winner: Sugar and Alcohol in Space

Two Winning Entries - HS & HS LondonWinning Entry Highgate School

6C Highgate School - Hannah Duffey

Sugar and alcohol, how far would we go to get them? Most of us are within walking distance of one or the other, but scientists have discovered a “relatively nearby” source of huge quantities of both. Analysis of comet Lovejoy by the Paris Observatory shows it contains alcohol in the form of ethanol, and sugar in the form of glycolaldehyde. The amount of alcohol being released each second, when the comet is most active, is equal to 500 bottles of wine.

Dirty snowballs – the unappealing description that scientists have traditionally given to comets – suddenly seems inadequate. It is true that comets are mostly ice and dust, only visible to eyes on earth as the sun vaporises the ice to form long trailing clouds.

We are surprised to find sugar and alcohol in space because on earth it takes a plant to make either – green plants to grow our sugar, and manufacturing plants to brew our alcohol. Both are complex processes, photosynthesis evolved over millions of years, and fermentation is a multi-billion dollar industry. For example, fermentation involves living yeast, catalysing the reaction of glucose into ethanol and carbon dioxide.

So are the sweets and booze on Comet Lovejoy being made by little green men? Or does the discovery of alcohol imply that some form of yeast will be found on the comet? Well, just possibly, but there is a far simpler explanation. Atoms of carbon, oxygen and hydrogen that are thrown out by exploding stars, sometimes collide and form organic molecules. Indeed, a decade ago, astronomers at Britain’s famous Jodrell Bank observatory discovered a cloud of methyl alcohol spanning a distance equivalent to 22 million earth diameters. Such organic compounds, produced by random collisions, are pulled together by gravity into comets.

But how do scientists know there is sugar and alcohol on Comet Lovejoy? It’s not because an astronaut has returned overweight and with an enormous hangover. Astronomers use spectroscopy to analyse the light given out by distant objects, knowing that the colours emitted are determined by the chemicals in the object. For example, Helium was actually discovered in space before it was found on earth, since the distinctive colour of the sun was shown in 1868 to be impossible to make with previously known elements.

We still know very little about comets. The very first mission to land a probe on a comet was launched in 2004, with the Philae lander touching down on comet 67/P on 12 November 2014. After a bumpy landing, Philae discovered many things, and identified the presence of organic compounds. Scientists analyzing the Rosetta mission data now say those organic compounds on comet 67/P include alcohol, but they were beaten to publication by the astronomers who have discovered alcohol on comet Lovejoy.

Clearly, the really important scientific question is “what do the sweets and booze on Lovejoy taste like”?

I volunteer to find out, since I’ll be old enough to drink by the time I get there.

Hannah Duffey
Highgate School

I am a 15 year old Londoner, though I’ve lived half my live in Malaysia, Sweden and Bulgaria. I will take A-levels next year, and plan to study Biology, Chemistry, Maths and French. I enjoy dancing, drama and hockey, and I’m very excited when I discover new places. I hope to learn many languages and have a job that includes communicating science.

As I say in my blog, I really would love to be an astronaut, for a decade or two. If that doesn’t work out, I’ll settle for exploring and protecting the planet!

School Winner: Busy Buzzing Bees

Two Winning Entries - HS & HS LondonWinning Entry Haverstock School

6C Haverstock School - Amy KitkannaWhat are your thoughts on bees? Don’t you just hate them? For some people bees are just an annoyance, I used to think this too (but bees are not as bad as we think, and as you carry on reading you’ll understand why). So, why do we hate bees so much? Is it because all they do is sting you and cause you pain? They’d buzz around loudly, come near you if you had anything sweet or chase you down the streets trying to sting you, but you shouldn’t be afraid of bees. Bees will only sting you if they feel threatened! So try avoid getting close to them, scaring them or stepping on them because a bee sting can hurt an awful lot.

On the other hand a sting from a bee isn’t all bad, a toxin in the bee venom called melittin could actually help prevent getting HIV, and apitherapy, (substances produced by an honey bee, e.g. venom) has also helped many patients who suffer from serious conditions such as multiple sclerosis, arthritis and lupus.

Bees are actually very significant to us and our lives! They’re not just for honey, they’re not just there to sting you either…. Even if you hate them, you need them.

Bees are hardworking insects, they may work harder than you do! During the colder seasons bees can live for up to nine months however in the summer they rarely last 6 weeks. They literally work to death. As bees age, they usually do jobs reserved for the younger members. Their brain stops ageing and instead their brain ages in reverse.

Believe it or not, bees are actually responsible for the food on our plate. One third of our global food supply is pollinated by bees. Without them, humans wouldn’t have much of a variety to eat. Bees keep the plants and crops alive.

The pollen from the crops attaches to the bees fuzzy bodies and rubs off on flowers as they collect nectar. The pollen transfer helps plants to reproduce and produce fruits and seeds.  Many crops are pollinated by bees, this is a list of a few; Almonds, apples, apricots, avocados, blueberries, cashews, coffee, cranberries, cucumbers, grapes, kiwis, mangoes, peaches, pears, peppers, strawberries, tangerines, walnuts and watermelons. These are only some of the few things bees pollinate. Without bees do you think we would still have these crops? Because we wouldn’t, without bees these crops wouldn’t even exist!

Bees are now slowly disappearing due to an extremely popular pesticide called Neonicotinoids, this is chemically similar to nicotine. Pesticides are harming the environment, and they are killing the organisms that help the world, and humans, survive. This is why we must protect the bees. But we can’t just blame it on the pesticides because us, as humans are partly to blame. Humans are also destroying wild habitats where bees traditionally get their food.

So think of it like this, by killing bees we are hurting ourselves.

SAVE THE BEES!

Amy Kitkanna
Haverstock School

My name is Amy Kitkanna and I am half Thai and half Laotian. I was born in London on the 15th December 2000, making me 14 soon to be 15. As well as being academic and always trying to understand everything that is being taught to me, I also enjoy being creative and like to use different materials to design and create something unusual. I also enjoy going on adventures to new places where I can enjoy and experience new things. I enjoy doing Biology, though it took me a while to feel like I was good at Science. Now I am studying Triple Science and am hoping to continue studying Biology at A level.