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Issue 4. June 2013

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IONIC Issue 4 - MESSAGE FROM THE EDITOR

Message from the editor Ionic Magazine 06.13 Welcome to June. It’s that one notorious month of the year when you’re encouraged to go wild, flip out, let loose and unleash all of your latent frustrations and rampant carnal urges on the world… if you’re a bat. But if you’re not then chin up, because June is looking good for humans too: for one, Ionic magazine’s Issue 4 is out and here is a taster of what to expect…. Discover how music can be tasted, why birds like cigarette butts and what secrets lie in the tapeworm genome. wNot to mention advances in osteoporosis treatments, weight loss surgery and how brain signals can be used to control prosthetic limbs. Then, look over to see the same story through an artist’s eyes. Art meet science, science meet art. An unlikely duo with truly stunning results. You’ve been waiting three months for this, and you didn’t even know it! Enjoy! To get involved for Issue 5 - please get in touch www.ionicmagazine.co.uk/getinvolved

Yalda Javadi Ph.D. Editor

@IonicMagazine facebook.com/ionicmagazine


IONIC Issue 4 - CONTENTS

Contents Crossfire of sensations (a firework of senses)

Lost in Space

By Helga Groll - Illustration by Jon Heras and Oliver Sin

By Karen Brakspear - Illustration by Carlos D. Toledo-Suarez

The genomes of nightmares

BEAM IN SCOTTY!

By Hayley Bennett - Illustration by Megan Lightfoot

By Tarandeep Jagdev - Illustration by Mita Brahma

Put a bird on it!

The Retina’s Unintuitive Wiring − Why Did Evolution Do That?

By Frederik Seelig - Illustration by Vanna Barber

Written and Illustration by Neil Murphy

Plugging in to outplay paralysis

The history and current status of weight loss surgery

By Lux Fatimathas - Illustration by David Purnell

By Anant Patel - Illustration by Beau Brady


Crossfire of sensations (a firework of senses) By Helga Groll http://naturalartiste.blogspot.co.uk/

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wish I was a synaesthete. “A what?” you ask. No, I am not talking about a profession or a new religious cult. Synaesthesia is a “neurological condition”, although this description hardly does it justice. Imagine a world, where every word, letter, number, emotion or music comes with its own signature colour or taste. This is what it is like for a synaesthete. Their world is colourful and tasteful because of a crossfire of senses. Synaesthetes can have blue Mondays, yellow Tuesdays, sour evenings or green threes, amongst others.

Synaesthesia comes from the ancient Greek words syn (union, together) and aisthesis (sensation) meaning joined sensation. And that’s exactly what it is – two independent senses experienced together1. There are over 60 forms of synaesthesia2. In ‘grapheme-colour’ synaesthesia, words, letters and/ or numbers are in colour and are often arranged in space. In ‘lexical-gustatory’ synaesthesia, words can elicit different tastes. Music or emotion can also evoke colours, and in the ‘mirror-touch’ synaesthesia, people experience tactile sensations when they see others being touched. This is also associated with a heightened emphatic ability3. In a rarer form of synaesthesia, people see auras, coloured outlines, around other people and objects1. Surprisingly, synaesthesia is relatively unknown and unresearched. The first documented case dates back to 18124, and synaesthesia has been more systematically described by Galton (1822-1911)5 later on, but after the early 1900s, research almost ceased.

Probably around 2-4% of the population have synaesthesia6. Many synaesthetes are not even aware that they experience the world differently to others, and sometimes only discover it by chance. Synaesthesia occurs from childhood on and people usually do not tend to lose it (and if they do lose it, usually it will be before the age of seven)1. Some forms of synaesthesia can be induced, either through accident, loss of a sense or drugs. In the early 1960s it was shown that LSD can lead to synaesthetic experiences1,5, but it is unclear if the mechanisms are similar. New research into synaesthesia has only recently been picked up again; but it’s mechanisms and underlying causes remain partially known. Structural differences in the brain and/or interactions between different brain centres are thought to explain some of the mechanisms7,8. Cross wiring and cross activation between different regions in the brain could lead to different senses being experienced at the same time. But researchers are unsure if the cross wiring between different brain areas is caused by the connectivity between neurons or by chemicals1,5. Brain imaging studies have also revealed differences in the brains anatomy. Synaesthetes appear to have connectivity clusters and the grey matter in some parts of the brain (parietal cortex and hippocampus) is thicker than in non-synaesthetes7,8. Researchers have also found increased connectivity and activity in centres processing texture, colour and form7,8,13.

By Jon Heras

http://www.e-nox.net/

IONIC Issue 4 - Crossfire of sensations (a firework of senses)


IONIC Issue 4 - Crossfire of sensations (a firework of senses)

Imaging techniques revealed that depending on the type of synaesthesia, centres processing taste, visual information or emotion are more active. Others suggest that the whole brain, and not just some areas, is strongly hyper-connected9.

1. Cytowic, R. E., & Eagleman, D. M. (2009). Wednesday is indigo blue: Discovering the brain of synesthesia. MIT Press.

Cases of synaesthesia are often seen within different members of afamily, suggesting a hereditary condition10. Although some similarities or patterns in the sensations can be observed between people, everyone experiences different sensations or combinations, even identical twins1. These combinations usually stay for life1.

4. Jewanski, J., Day, S. A., & Ward, J. (2009). A colorful albino: the first documented case of synaesthesia, by Georg Tobias Ludwig Sachs in 1812. Journal of the History of the Neurosciences, 18(3), 293-303.

Many synaesthetes work in the artistic industry. Some are famous; including the philosopher Ludwig Wittgenstein, the musician Miles Davis, the Nobel Prize physicist Richard Feynman, the author Vladimir Nabokov, and many more5. I have to say that I envy synaesthetes. Although their sensations can lead to an overload of experiences at times, it must be amazing to see the world in technicolours. This ‘additional sense’ shows us how fascinating the brain is and how little we still know about all its functions. Synaesthesia opens a new window of research for neuroscientists, philosophers and linguists; not only to understand this phenomenon, but also to learn more about brain mechanisms and individual differences in perception.

2. Spector, F., & Maurer, D. (2009). Synesthesia: a new approach to understanding the development of perception. Developmental psychology, 45(1), 175. 3. Banissy, M. J., & Ward, J. (2007). Mirror-touch synesthesia is linked with empathy. Nature neuroscience, 10(7), 815-816.

5. Ward, J. (2013). Synesthesia. Annual Review of Psychology, 64, 49-75. 6. Simner, J., Mulvenna, C., Sagiv, N., Tsakanikos, E., Witherby, S. A., Fraser, C. & Ward, J. (2006). Synaesthesia: The prevalence of atypical crossmodal experiences. Perception, 35(8), 1024. 7. Rouw, R., & Scholte, H. S. (2007). Increased structural connectivity in grapheme-color synesthesia. Nature neuroscience, 10(6), 792-797. 8. Rouw, R., Scholte, H. S., & Colizoli, O. (2011). Brain areas involved in synaesthesia: a review. Journal of Neuropsychology, 5(2), 214-242. 9. Hänggi, J., Wotruba, D., & Jäncke, L. (2011). Globally altered structural brain network topology in grapheme-color synesthesia. The Journal of Neuroscience, 31(15), 5816-5828. 10. Baron-Cohen, S., Burtlf, L., Smith-Laittan, F., Harrison, J., & Bolton, P. (1996). Synaesthesia: prevalence and familiality. Perception, 25, 10731079.

By Oliver Sin

http://oliversin.eu


IONIC Issue 4 - The genomes of nightmares

The genomes of nightmares By Hayley Bennett - http://uk.linkedin.com/pub/hayley-bennett/1b/288/539

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apeworms have a life cycle that most people would probably describe as hideous. An adult tapeworm lives in the intestine and releases segments of itself called proglotiids, packed full of infectious eggs. In humans, the long, flat, ribbon-like adults may cause unpleasant abdominal symptoms and nutritional deficiency as they steal food from inside the intestine. If infectious tapeworm eggs are accidentally ingested, through poor sanitation or unwashed food, they can pose a much more serious health problem. When this happens early larval forms of the worm work their way into the body, infiltrating muscles and vital organs. Here, they hide out in pearly round cysts (of their own making), resistant to attack by the human immune system. The young larvae’s plan is to wait for the host to die so that they can be eaten and develop in to adult worms. Meanwhile the cysts grow; over time some can grow larger than the size of a baseball. The cysts may also multiply themselves, spreading the infection. The fluid-filled cysts can cause serious health risks. For example, the hatched larvae of the pork tapeworm, Taenia solium, tend to grow into cysts in the brain, causing seizures, meningitis, dementia or death. Sadly, this dramatic horror is all too real for many people across the world. Treatments can involve surgical removal of cysts, however, often this is not a possible option and drugs currently used for treatment of tapeworm cysts are not very effective. A recent paper comparing the genomes of four tapeworm species sheds light on previously unknown characteristics of these monstrous organisms. As well as being interesting in terms of biology, the findings

will hopefully lead to better treatment strategies for the unlucky victims of tapeworm infection. From their genomes, several genes have been identified that tell us how the worm steals its energy from the host, scavenging for fats and cholesterol. In fact, the results showed that they lack genes that allow them to make some of their own essential nutrients, indicating just how dependent they are on their hosts for life. One particular gene was identified that is likely to make a great target for drugs because it is so essential. In other animals there are two separate genes, but in tapeworms there is just the one. The enzyme, called thioredoxin glutathione reductase (TGR), is involved in detoxifying the worm, and without it the worm would die. The larval cysts of tapeworms have been compared to cancer because they show uncontrolled growth and invasion of tissue, and are hard to kill without also damaging surrounding organs. In the tapeworm genomes the scientists found several genes that are also the targets of cancer drugs, and crucially these are active in the hard-to-kill cysts. This means that cancer drugs, already licensed for use in humans, could be repurposed to treat tapeworm cysts without the expensive and lengthy process of developing an entirely new drug. Tapeworms are by their nature secretive and cunning organisms, hiding inside of us. But their genomes have revealed their weaknesses – they had better watch out. Tsai and Zarowiecki et al., Nature 496, 57–63 (04 April 2013) doi:10.1038/ nature12031

By Megan Lightfoot

mvlightfoot@gmail.com


IONIC Issue 4 - PUT A BIRD ON IT!

Put a bird on it! By Frederik Seelig http://nl.linkedin.com/pub/frederik-seelig/7/661/43aa

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nless you’re a character from the TV series “Mad Men”, you will most likely by now have realised that smoking is bad for your health. It will give you bad breath and wrinkles, not to mention lung cancer. But while this is true for humans, a recent study1 from Mexico found evidence for birds taking the opposite approach. As part of her MSc thesis, Monserrat Suárez-Rodríguez and her colleagues from the Universidad Nacional Autónoma de México found that city-dwelling birds add discarded cigarette butts to their nests to repel parasites. It’s not the first time this behaviour is reported. Other species in other locations do it as well, which left the researchers wondering whether it was more than just a coincidence. Nicotine, the main active component of cigarette smoke, is used extensively in agriculture to repel insect pests from crops or against parasites in poultry farming. Arthropod ectoparasites (parasites such as fleas, lice, ticks and mites that live on the body surface of a host) suck blood from warm-blooded animals and can transmit diseases in the process, thus becoming a huge burden on nestlings and adult birds.

For their study, the researchers studied the house sparrows (Passer domesticus) and house finches (Carpodacus mexicanus) living on their Mexico City campus. They attached electric heating devices to nests of breeding birds to attract heat-seeking parasites that were then trapped with adhesive tape. To test whether the nicotine from smoked cigarette butts had any impact, cellulose fibers from smoked and non-smoked butts were compared. After counting the parasites caught on the strips of sticky tape, the researchers could show that thermal traps laced with

cellulose from smoked butts attracted significantly fewer mites than traps with non-smoked butts. In a second step, once the breeding was finished and the birds had left, the empty nests were dissected, weighed and any parasites within identified and recorded. They found that over 80% of nests from both bird species contained smoked cigarette butts, and discovered that they clearly reduced the number of encountered parasites. The animal kingdom is full of examples of selfmedication. Monkeys eat certain plant species after becoming sick, and expecting elephants ingest clay to induce labour. But this is the first report of animals using artificial materials. While it would be a stretch to assume that sparrows and finches deliberately choose smoked butts because of their repellent qualities, this seems to be a new adaptation to an urban environment. Other bird species have been shown to weave green plant material into their nests to repel parasites2-4, so by picking up cigarette butts the birds of Mexico City could be using “new ingredients for an old recipe”.

1. Suárez-Rodríguez, M., López-Rull, I., Macías Garcia, C. Incorporation of cigarette butts into nests reduces nest ectoparasite load in urban birds: new ingredients for an old recipe? Biology Letters 9: 20120931 (2012). 2. Wimberger, P. H. The Use of Green Plant Material in Bird Nests to Avoid Ectoparasites. The Auk, 101(3): 615-618 (1984). 3. Clark, L., Russell Mason, J. Use of nest material as insecticidal and antipathogenic agents by the European Starling. Oecologia 67(2): 169-176 (1985). 4. Lafuma, L., Lambrechts, M. M., Raymond, M. Aromatic plants in bird nests as a protection against blood-sucking flying insects? Behavioural Processes, 56(2): 113-120 (2001).

By Vanna Barber

https://twitter.com/vannabarber


IONIC Issue 4 - Plugging in to outplay paralysis

Plugging in to outplay paralysis By Lux Fatimathas https://www.facebook.com/l.fatimathas

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ith roughly 650 muscles in our body in need of instruction, the human nervous system has a mammoth task in sending out the correct commands to each and every one of them. The intricate web of nerve cells that carry these commands can easily be damaged. For Hollywood actor Christopher Reeve, this took place in one short moment when he was thrown from a horse, leaving him tetraplegic – unable to move all four of his limbs. Repairing this damage is often impossible. It is from this seemingly insurmountable roadblock that neuroprosthetics springs; a field dedicated to the development of devices that substitute for the loss of nerve cell function. The damage to Reeve’s nerve cells that led to his tetraplegia was almost instantaneous. For 52-year-old Jan Sherman1 however, this same fate was 13 years in the making. Spinocerebellar degeneration was the culprit – a genetic disorder that causes nerve cells to degrade, gradually chipping away at the body’s ability to control its muscles until finally paralysis takes hold. The degenerating nerve cells are specifically found within the spine and a region of the brain called the cerebellum, which coordinates commands from the rest of the brain telling our muscles to move. Sherman’s cerebellum was luckily unaffected by her condition, but without fully functional nerves running down her spine, she was still left paralysed. Unlike most patients who receive this diagnosis, Sherman was given the opportunity to test the latest in brain-machine interfaces. Two electrodes were connected to the region of her brain that controls movement, called the motor cortex. These electrodes were plugged into a recording device that captured the signals being fired off from her nerve cells.

By David Purnell

http://www.behance.net/davidrpurnell

A computer then converted these signals into a language a prosthetic arm could understand, using a ‘neural decoder’. Connecting the computer to the motorised arm completed the information highway and a 13-week training regime began. The prosthetic arm was designed to move with ‘seven degrees of freedom’ – about the amount of flexibility it takes to reach out for a glass of water and bring it to your mouth. A human arm is capable of mastering 25 degrees of freedom2. As the weeks rolled by Sherman grappled with a variety of tasks usually used to assess stroke patients. These trials focused on gripping and grasping movements that would be of use during daily living, including picking up different sized blocks and balls and stacking cones. Without the aid of the prosthetic arm, Sherman was unable to complete any of these tasks, scoring 0 out of a possible 27 points. Week on week her brain learnt to tweak its activity patterns to better communicate with the prosthetic arm. By the end of the training regime her score had risen to between 15 and 17. Any increase greater than 5.7 points is said to be a clinically significant improvement in function, with the potential to improve a patient’s quality of life. Work is already underway to further develop the range of movements the prosthetics can achieve and also remove the need for cables by using wireless technology. Stepping farther into the future, it is hoped the prostheses will one day be able to send impulses back to the brain to convey the sensation of touch, ultimately providing those suffering from paralysis a greater ability to engage with their surroundings.

1 http://motorlab.neurobio.pitt.edu/multimedia.php Breakthrough episode video, Schwartz Lab website 2 http://www.technologyreview.com/news/421347/robotic-limbs-that-plug-intothe-brain/?p1=A4 Robotic Limbs that Plug into the Brain, Technology Review


IONIC Issue 4 - LOST IN SPACE

Lost in Space By Karen Brakspear https://twitter.com/karenbrakspear

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roken bones are a common occurrence in the playground but are unfortunately frequent in the elderly too, due to the natural loss of bone mass as we age. Bones that are less dense are less strong and break more easily; individuals with particularly weak bones account for the 200 million osteoporosis sufferers worldwide1. The activity of the cells which continually remodel our bones – the osteoblasts (bone forming cells) and osteoclasts (bone destroying cells) – are normally balanced to uphold healthy skeletal strength. The problem is that as we get older we lose more bone than we are able to make. So can we recapture this balance in bone remodelling for osteoporosis sufferers? Effective medications exist that slow bone loss but there are few drugs at hand that increase bone formation. One way to push osteoblasts to increase their bone forming activity is to mimic the signals that occur following physical weight-bearing exercises such as running. When we run, bone formation is stimulated and bone loss is reduced to meet the physical demand. Likewise, if bones are not used, which we see encountered by astronauts in a weightless environment, bone loss of up to 1-2% per month can occur2. Osteocyte cells within the bones sense the physical force (or mechanical load) and signal through one another to osteoblasts and osteoclasts at the bone surface. Many signals are involved in this process but one signalling protein that is the target of a drug currently under development is sclerostin. Sclerostin is produced by osteocytes and its production is reduced by mechanical load.

This is because it acts to prevent another signalling protein from telling osteoblasts to start multiplying and make more bone. Sclerostin levels in the blood increase naturally with age, coinciding with a decrease in bone mass, although this increase is diminished in physically active adults3. Drugs are being developed by pharmaceutical companies that can recognise sclerostin, bind to it and prevent it from carrying out its normal activities. Published findings from a phase I clinical trial showed that injection of a single dose of the drug could increase multiple markers of bone formation and potentially also reduce bone loss4. The trial was conducted on healthy males and post-menopausal woman, but the results do suggest that it may be useful in the future in reducing fracture risk in osteoporotic patients. Further trials of the drug are currently under way and the results are expected to be published later this year.

1. Cooper, C., et al. Osteoporosis International 2(6) 285-9 (1992) 2. Lang, T., et al. Journal of Bone and Mineral Research 19 1006-1012 (2004) 3. Amrein, K., et al. Journal of Clinical Endocrinology and Metabolism 97(1) 148-54 (2012) 4. Padhi, D., et al. Journal of Bone and Mineral Research 26(1) 19-26 (2011)

By Carlos D. Toledo-Suarez

http://www.artistasdelatierra.com/artistas/ctoledo/


IONIC Issue 4 - bEAM ME IN SCOTTY!

Beam Me In, Scotty! By Tarandeep Jagdev http://valistrianchronicles.wordpress.com/

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ere’s one to add to your Christmas wish list: a laser beam that has the power to move objects from one location to another. What may seem like science fiction (Star Trek fans, eat your hearts out!) is now actually the stuff of science fact! A group of researchers have found out just how to make a real life tractor beam that is able to move objects, albeit microscopic ones, or keep them stationary. It may be less impressive than the tractor beams featured in Star Trek but it is certainly a step in the right direction! Led by the University of St. Andrews, the new research follows on from ideas of Johannes Kepler, a German Astronomer in 1619. Kepler’s observations of comets led to the conclusion that microscopic objects follow the direction of light photons (‘packets’ of light) when hit by a beam of light. This new piece of research has focused on a technique to reverse this force, effectively allowing small objects to be ‘pulled’ towards a beam of light. Although the technique is quite recent, its potential applications are huge. The beam is already gaining popularity amongst all manners of disciplines. From a medical perspective, the beams could be used to separate mixtures of substances or chemicals by focusing on particular aspects of the mixture. For example, isolating white blood cells from a typical sample of blood. Aside from medicine, the tractor beam also has the potential to be used by NASA as a way of collecting atmospheric or dust samples from space.

By Mita Brahma

http://www.mitabrahma.com

However, there are obstacles that will need to be overcome before we can recreate a Star Trek-like beam capable of trapping space ships, which we’ve seen on sci-fi shows. Mainly because scaling up the beam size will create an immense transfer of energy that will cause huge overheating issues; your tractor beam suddenly becomes a superheating death ray. Perhaps not the intended use… But regardless, at least we know that such a beam exists. It may not meet the specifications of the U.S.S. Starship Enterprise of the Star Trek series, but for now, it is definitely enough of an achievement to impress.

Brzobohatý, V. Karásek, et al., Nature Photonics: 7, 254 (2013)

Dedicated to my sister Harminder and her new husband Sanjeet


IONIC Issue 4 - THE RETINAis unintuative wiring - why did evlution do that?

The Retina’s Unintuitive Wiring − Why Did Evolution Do That? By Neil Murphy http://neilmurphystudio.com/

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magine you’re in a dark room with a single window. You have a photocell (a device that converts light into electricity) in one hand and a computer chip in another, and wires connecting them together. Logic states you position the photocell near the window and make sure the connecting wires do not block light from falling on the photocell. Simple right? Why then, did evolution ‘think’ differently and construct our photocells - the mammalian retina - with layers of neuronal wiring in front of our photoreceptors? As our eyes are constructed, photons pass through the cornea, lens and transparent vitreous humor before they finally reach the retina. The retina itself has layers, and photons must penetrate all of them before they finally strike our eye’s photoreceptors at the very back. The retina’s layers

First light must pass through the nerve ganglion layer – the ‘wiring system’ whose axons ultimately converge to form the optic nerve. The ganglion layer is followed by three more: the amacrine, bipolar and horizontal cell layers through which the photons must pass before they arrive at their target photoreceptor cells – the rods and cones. These cells do more than just transmit signals upward to the nerve ganglion layer. They are responsible for decoding motion (for example, downward motion) and time-based information (speed of the downward motion) from the photoreceptor; much of the signal that process form, movement and color take place within these very layers. After this initial processing, the signals are passed back up toward the ganglion nerves and on to our visual cortex.

Behind the photoreceptors, a dark pigmented retinal pigment epithelium layer exists, which absorbs stray photons and prevents them from reflecting back to the rods and cones, ensuring an efficient system. So why this arrangement? It’s all about energy

Our photoreceptor cells require an enormous amount of energy to function. Light-responsive molecules are constantly being used, metabolized and renewed; therefore, they need constant readily available energy. In fact, they require more oxygen, glucose, retinol (a form of vitamin A), water and other nutrients than almost any other part of the body. To position a circulatory system able to meet these demands anywhere but immediately behind and available to the photoreceptors would interfere with incoming light far more than the existing layers do. Let’s return to our electrical photocell analogy. If the photocell needed to be continuously refurbished to keep working, and doing so required all the manufacturing equipment used to originally produce it, you would want to keep that equipment behind the photocells − not in front of them where it would certainly block much of the light coming through the window. Voila. Stay close to the hand that feeds you. It seems evolution got it right after all.

1. Kandel, Schwartz, Jessel, Principles of Neural Science. Chapter 24 (2001) 2. Bergman, J., Journal of the American Scientific Affiliation. 52(1):18-30 (2000) 3. Strauss, O., American Physiological Society. The Retinal Pigment Epithelium in Visual Function (2013) 4. Kolb, H., Webvision: The Organization of the Retina and Visual System (2011)


IONIC Issue 4 - THE HISTORY AND CURRENT STATUS OF WEIGHT LOSS SURGERY

The history and current status of weight loss surgery By Anant Patel anant.patel@doctors.org.uk

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oday, rarely a day goes by without a new headline highlighting the perils of the international obesity ‘epidemic’. Well-established health risks associated with obesity include heart disease, stroke and diabetes to name but a few, and the cost of treating them (estimated at over $100billion/ year in the USA1), not to mention the economic cost of premature mortality and lost days from work, provides a clear rationale for intervention. Treatments include behavioural, medical and surgical techniques, and although the latter should only be considered when patients’ non-surgical attempts have failed, the rates of these ‘bariatric’ surgical procedures continue to rise. The first case reported in the medical literature was the ‘jejuno-ileal bypass’ performed by Dr Kremen and his colleagues in Minnesota in 1954. This spawned an era of advancement in bariatric techniques, with the last 50 years seeing a significant increase in the diversity of types of procedure, and an improved understanding of long-term benefits and complications. Weight loss is generally achieved by two methods in bariatric surgery: malabsorptive and restrictive procedures. Malabsorptive procedures, achieve weight loss by decreasing the effectiveness of nutrient absorption in the gut, through shortening the length of functional small bowel. Restrictive procedures, on the other hand, reduce the capacity of the stomach and thereby the caloric intake, by inducing early satiety – they simply cause the patient to feel ‘full up’ earlier. An example of a purely restrictive method is “gastric banding”, in which an adjustable inflatable device is placed around the upper part of the stomach. This method benefits from being adjustable,

reversible, and achieved through minimally invasive ‘keyhole’ surgery. Malabsorption and restriction can be achieved by a popular technique known as ‘Roux-en-Y’ bypass, which involves creating a small stomach pouch, and shortening the length of functional small bowel. Even this technique, which requires considerable re-plumbing of the intestinal tract, is now being performed through keyhole techniques by experienced surgeons. When patients who have undergone bariatric surgery are compared to age, sex and weight-matched obese subjects, the benefits are shown to be very promising in the medium and long-term. Surgical techniques have not only been shown to achieve an average excess weight loss of around 60%2 but also resolution or improvement of diabetes, high blood pressure, high cholesterol and sleep apnoea in 60-80% of patients3,4. This translates to a reduction in mortality of around 30-40% at 10 years5. The benefits of medical and behavioural treatments pale in comparison. Of course, all surgery comes with its complications. Although Dr Kremen and his team saw their early procedure produce significant weight loss, many patients also suffered the unacceptable consequences of severe diarrhea, dehydration, electrolyte imbalances, and in some cases acute liver and kidney failure. The procedure is no longer performed due to its unacceptable mortality and complication rate. In Dr Kremen’s day, and for almost four decades following, before the advent of keyhole surgery, all weight loss procedures required invasive surgery with longer hospital stays and considerable complications. Today, the 30-day mortality rate has dropped to less than 1%.

Complications vary according to procedure, and although those such as blood clots and bowel leaks (at sites where bowel is rejoined surgically) can be serious, the overall incidence of significant complications requiring rehospitalisation is much reduced.

1. Ludwig DS, Pollack HA. Obesity and the economy: from crisis to opportunity. JAMA. 2009;301(5):533 2. Buchwald H, Avidor Y, Braunwald E, Jensen MD, Pories W, Fahrbach K, Schoelles K. Bariatric surgery: a systematic review and meta-analysis. JAMA. 2004;292(14):1724. 3. Maggard MA, Shugarman LR, Suttorp M, Maglione M, Sugerman HJ, Sugarman HJ, Livingston EH, Nguyen NT, Li Z, Mojica WA, Hilton L, Rhodes S, Morton SC, Shekelle PG. Meta-analysis: surgical treatment of obesity. Ann Intern Med. 2005;142(7):547 4. Buchwald H, Estok R, Fahrbach K, Banel D, Jensen MD, Pories WJ, Bantle JP, Sledge I. Weight and type 2 diabetes after bariatric surgery: systematic review and meta-analysis. Am J Med. 2009;122(3):248 5. Adams TD, Gress RE, Smith SC, Halverson RC, Simper SC, Rosamond WD, Lamonte MJ, Stroup AM, Hunt SC. Long-term mortality after gastric bypass surgery. N Engl J Med. 2007;357(8):753

By Beau Brady

beau.brady@live.co.uk

4. Buchwald H, Estok R, Fahrbach K, Banel D, Jensen MD, Pories WJ, Bantle JP, Sledge I. Weight and type 2 diabetes after bariatric surgery: systematic review and meta-analysis. Am J Med. 2009;122(3):248 5. Adams TD, Gress RE, Smith SC, Halverson RC, Simper SC, Rosamond WD, Lamonte MJ, Stroup AM, Hunt SC. Long-term mortality after gastric bypass surgery. N Engl J Med. 2007;357(8):753


IONIC Issue 4 - CONTRIBUTE TO THE NEXT ISSUE...

Contribute to the next issue.... The last word.

GEEK: Whether you’re a scientist, science writer or science enthusiast and

want to write about new research breakthroughs and advances in technology, and see it transformed into an art piece, then Ionic wants to hear from you.

CHIC: Tell a scientific story in a way that has never been told. Offer your unique perspective and bring science to life through your creativity and imagination. Artistic license guaranteed.

Copyright © 2012 Ionic Magazine Writers and artists own Copyright © on their own work. Copy editer Xavier Roeseler

Magazine design - Thomas Weaver www.thomasweaverdesign.co.uk

By Oliver Sin

http://oliversin.eu

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