SYNAPSE THE SCIENCE MAGAZINE WRITTEN BY STUDENTS FOR STUDENTS
ISSUE 2 - June 2012 - FREE
How essential is your Immune System?
Whatever you are doing your immune system will be continuously fighting to protect your body against foreign material which threaten to cause you harm
Introspection: How does it happen? Have you ever thought about thinking?
Seeing with your tongue Pain relief without addiction? The Magic of Mushrooms
EDITORIAL
H
ello! Welcome to the second issue of Synapse Science Magazine, the University of Bristol’s student science magazine. Please take your time to read through and show the magazine to your friends. If you have any comments or wish to join our magazine as a writer, editor, photographer or graphic designer please let us know by contacting synapse.scimag@gmail. com. Also, please visit our new website - www.synapsebristol.co.uk
Tom Stubbs
Editor In Chief Senior Editor and Vice President
Senior Editor and Graphic Designer
Senior Editor and Treasurer
Senior Editor and Secretary
Felicity Russell Oliver Ford
Daniel Ward
Louise Brown ARTICLE EDITORS
Rachel Greenwood Heather Randles
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Georgina Maguire Thomas Mitchell
Louisa Cockbill
Harrison Carter
Maxine Penny
Saraansh Dave
Becky Brooks
Alex Pavlides
Molly Bridge
Sky Ng
CONTENTS
Articles
On the cover
16
How essential is your immune system?
7 Seeing with your tongue 8
Pain relief without addiction?
9
The magic of mushrooms
distinction of 4 The mirror images
5 The telegraph plant Makeover 6 AforHealthy the Hot Dog
12 Transplanting Memories
Introspection:
10 How does it happen?
13 Blood Crisis 14 Science Fiction
Features
10
Introspection: How does it happen?
think of the 15 Just money
Have you ever thought about thinking?
16
How essential is your immune system?
20
Should biological sex be considered neurological destiny?
22
Careers in Science
that feed 18 Microbes the world perils of 19 The publicising science
Join us online!
www.synapsebristol.co.uk @synapsebristol
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ARTICLES
he distinction of mirror images
Kate Hammond
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espite initial appearances the majority of mirror images are not identical. Each half has a distinct orientation, one left and one right. However, we appear not to retain this orientation information. Massachusetts Institute of Technology research scientist Daniel D.Dilks asked a random selection of people to recall the direction in which the queen was facing on a one penny coin. Only 50% could correctly identify her direction; even though it is an object seen everyday, the results were as if by chance. This would suggest that our memory of an object is actually independent of its orientation. Similarly, an advertising campaign presented two copies of the Mona Lisa to volunteers. In one (the original) she faced to the left and in the other (a manipulated version) she faced to the right. Although all easily identified the picture as the Mona Lisa, very few could say with confidence which was the correct version. The advertising campaign used the slogan ‘don’t mistake familiarity for knowledge’, but what can also be taken from this is further evidence that we represent the identity of an image in our memory independent of its
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Can you tell which is the right Mona Lisa?
orientation. Practically, it makes little sense to store information regarding the orientation of objects. Distinguishing mirror images is very rarely needed, and, furthermore, we need to be able to recognize objects from all view points. However, it has also been shown that for a short period of time immediately after viewing an object, orientation information is retained. Looking at an object, looking away, and picturing it immediately afterwards confirms this. This has lead to a major theory concerning object recognition; objects are remembered as seen from a particular point of view, but the brain has adapted so that it stores with it its mirror image. The object can then be matched equally easily to itself
or to its mirror image. In this way, the initial orientation information is lost. Although it is mainly advantageous, this adaptation also has its downfalls. The visual system begins life unable to distinguish mirror images in memory. Consequently, when it is necessary to distinguish between two mirror images, we have to learn to encode each mirror image as an object in its own right. Taking the every day example of b/d and </>, little children struggle to distinguish between the two but over time the mirror images acquire the status of separate objects. This explains why everyone is able to picture b or d in their head, but is unable to picture the orientation of a coin.
Jessica Fennell
The Telegraph Plant
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odariocalyx motorius, the Telegraph plant, from the species name you may guess an interesting feature of this plant - it can move! In fact, several plants move towards stimuli such as light, water or away from gravity. What makes this one special is that it moves towards the light in a short time frame. This means we are able to watch it actually happen right in front of our eyes, instead of having to whip out the deck chair and hang around for hours on end. The mechanics of the Telegraph plantâ&#x20AC;&#x2122;s movement are pretty strange. Instead of wasting a huge amount of energy to move the large leaves towards the sun every time there are a few rays bursting through the clouds, the plant has two satellite leaves which act as sun detectors. They move around in an elliptical pathway and therefore are able to detect sunlight and direct the larger leaf in the sunniest direction. This becomes most obvious when the plant is put next to a window. As a cloud covers the sun it will shiver and move from its original position, then as soon as the sun returns, its satellite leaves will start the elliptical pattern
all over again. At night, this system shuts down as there is no point in trying to find light when there is none. The plant effectively goes to sleep with the leaves hanging down. These plants are found mainly in Eastern countries, such as Bangladesh, India and China. They are widely distributed, but certainly not common. The plant has small purple flowers and contains several substances that are useful in medicine, such as various alkaloids. It is possible to take cuttings of these plants and they will grow very fast. So if you do happen to come across a Telegraph plant and like the look of it, stick a cutting into a flowerpot and soon you will see the satellite leaves whizzing right before your eyes! You can also buy the seeds, which have a netted pattern on their surface. They are resilient to pests as their mix of alkaloids protects them from a large variety of insects and the like. So if you are unsure of what to get a relative for a Birthday, or like to be entertained by plants in the sun moving with the breeze even when there isnâ&#x20AC;&#x2122;t one, The Telegraph Plant is your ideal candidate.
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ARTICLES
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A Healthy Makeover Emilie BergstrĂśm for the Hot Dog
ith rates of obesity rising at an alarming rate, it is becoming more and more crucial to find healthier alternatives to our favourite high-fat foods, specifically to reduce the amount of saturated fat in our diets. Today, a quarter of adults in the UK are classed as clinically obese. It is estimated that by 2020, this will increase to 80% of men and 70% of women, unless we make radical changes to our diets. Obesity, and the diet high in saturated fat that is widely associated with it, increases the likelihood of a number of lifethreatening diseases; cardiovascular disease, type 2 diabetes, certain types of cancer and arthritis, to name just a few. It is also estimated that obesity costs the NHS a massive ÂŁ5 billion per year. In an attempt to reduce the consumption of saturated fats, research has been done in recent years to investigate ways in which these fats can be replaced by healthier vegetable oils. This is a complex task as it is saturated triglycerides, the main constituent of saturated
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animal fats, that provide the solid structure and texture of the fats. Foods such as cheese, meat, ice cream and salad dressings require saturated fat to give them the consistency and taste that we are familiar with. Replacement of saturated fats with unsaturated oils reduces, and in some cases eliminates altogether, these solid properties. To give the vegetable oils a solid-like structure, innovative structuring methods are required. A group of scientists in Canada have investigated the use of organogelation, the process of using a compound to gel an organic liquid, to modify the structure of unsaturated liquid oils and create a plastic fat that has solid-like properties. Ethylcellulose, a polymer derived from cellulose, which is a structural polysaccharide in plant cell walls, was found to be a successful structurant. The group discovered that when ethylcellulose was added to liquid oils in concentrations of between 4 and 10% and heated to 130oC, it was possible to structure the oil into a trans-
parent gel, named an oleogel. A variety of different oleogels were created, each made from 10% ethylcellulose and 90% vegetable oil; the vegetable oils used included canola, soybean and flaxseed oil. The properties of the gels were tested using texture profile analysis and a mechanical method. But what does this mean for our hot dogs? To test whether these gels could actually be used in real foods, the team made Frankfurter sausages using canola oil oleogels. According to their research, the sausages did not show significant differences in chewiness or hardness when compared to regular Frankfurters made with beef fat. These findings suggest that in the future ethylcellulose oleogels could be designed and manufactured with special textural properties to replace saturated fat in a variety of food products. Watch this space to see if oleogel Frankfurters appear on our supermarket shelves in the near future!
I
t seems that in the near future there will be an additional assistive technology for blind people alongside guide dogs and white canes; the Brainport. This revolutionary device has the potential to improve the quality of life for people suffering from blindness all over the world. It is an experimental, non-surgical, assistive visual prosthetic device that transmits visual information from a camera to the brain via electrical stimulation of the tongue. In the 1960’s and 70’s, at the Smith-Kettlewell Institute in San Francisco, a team of scientists, led by Professor Paul Bach-y-Rita, started doing research in this area. Essentially, a BrainPort is a tiny digital camera about 1.5 centimetres in diameter, mounted on a pair of sunglasses. When worn by the individual it transmits visual signals via an electrode onto the tongue. The electrode array resembles a square plastic lollipop which can be placed on the tongue or removed at will. A handheld unit contains a zoom control, light settings and shock intensity levels as well as a central processing unit that translates the visual information into stimulation of the tongue, replacing the role and function of the retina. The stimulation pattern is displayed on the tongue, creating an image by presenting white pixels as a strong stimulation, black pixels as no stimulation and grey pixels as a medium level of stimulation. In order to ‘‘see’’ the environment, the individuals just have to put the “lollipop” (electrode) in their mouth, where the digital video camera images are converted to electrical impulses that the person will sense with their tongue, when
Seeing with your tongue
Raluca Pop
it makes contact with the lollipop. Most BrainPort users reported that the feeling is like Champagne bubbles effervescing on their tongue, or like a pins and needles sensation. The BrainPort is based on electro-tactile stimulation for sensory augmentation or substitution. More simply, it is the ability to use encoded electric current in order to represent sensory information by applying it to the skin, from where it will travel to the brain. The brain can be trained to learn how to interpret any sensory information that cannot arrive through a traditional channel, as if it were being sent through the “natural pathway”; this principle is based on the idea that the brain can adapt itself to interpret sensory information even if it is not provided through the natural channel. Paul Bach-y-Rita famously stated that “we see with our brains, not with our eyes; the optical image does not go beyond the retina where it is turned into spatio-temporal nerve patterns of impulses along the optic nerve fibres. The brain then recreates the images from analysis of the impulse patterns.”
we see with our brains, not with our eyes...
Although not a substitute for 20/20 vision, the BrainPort does give blind individuals an increased awareness of their surroundings by improving their abilities to orientate, be mobile and recognise objects. In addition, BrainPort could be suitable for people with visual defects such as glaucoma, which leads to the loss of peripheral vision and macular degeneration, which degrades sight at the center of the visual field. Scientists are working together to improve the BrainPort by making it cheaper and more accessible to the population, providing the chance of an easier and better quality of life to those suffering from visual impairment. As Erik Weihenmayer, who was given the opportunity to test-run BrainPort, stated, this device will give blind people, “a better chance of being in the thick of things instead of listening to life go by.”
BrainPort device
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ARTICLES
Pain relief without addiction? Improving Opioids by knowledge of their receptors
don’t remove pain but activating the Opioid receptors leads to a series of effects that mean an individual has increased pain tolerance and decreased perception of pain, they don’t feel the discomfort. Effectively the patient feels “high”, so discomfort bothers them less. These drugs are widely used in healthcare to help patients deal with pain but have one obvious drawback: they are addictive and patients regularly experience “cold-turkey” type The atomic structure of an Opioid receptor withdrawal symptoms due to dependence. This limits the Katherine MacInnes amount and regularity that doctors are willing to prescribe he prescribed drugs morphine and codeine belong these types of drugs. Opioid receptors are part to a group of drugs called of a group belonging to a Opioids. They are related to large family called GPCRs heroin (or diacetylmorphine) in structure; and are infamous (G-protein Coupled Recepfor being highly addictive and tors). Most Opioid drugs don’t have just one target but act on harmful. other GPCRs and therefore Opioids are incredibly produce many undesired effects important in medicine for in addition to pain relief (i.e. pain-relief. They function by vomiting). Apart from this, binding to receptors on the surface of cells in the brain and each drug acts on a particular spinal cord as well as the diges- receptor in a slightly differtive tract. These receptors are ent way. Imagine a host at a imaginatively named “Opioid” party that will shake hands with every guest (the receptors) receptors after Opium, the but treats each differently, and first drug in the group to be discovered. Stimulation of the hence different responses result. receptors by binding of Opioids Then imagine the same guests are met by a different host (a leads to feelings of euphoria different drug) who again treats and sedation. These drugs
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them slightly differently. You can see how complicated it gets to work out exactly how a drug is acting on a receptor and what effect it produces! A huge amount of research is being put into learning more about the Opioid group of receptors. In particular researchers are trying to solve the structures in order to visualise the three dimensional targets of Opioids. It is hoped that new Opioids can be synthesised that act on the desired Opioid receptor in a more specific way such that the negative downstream effects are avoided. This is expected to be made easier by looking at the shape of the binding sites of the drugs. In a perfect world of drug design it would be possible to work out exactly which receptor to target and in what way we want a drug to bind to produce the precise sedative effect. However, we just don’t know enough to do this yet, but greater knowledge of receptor structure can help to inform us of what might work. Eventually it is hoped that it will be possible to design an Opioid drug that allows the patient to be comfortable, while producing no feelings of dependence or addiction, and consequently putting doctors at ease about prescribing such drugs.
The Ma gic of Mushrooms Hazel Roberts
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ave you ever looked at a humble mushroom squatting in the leaf litter and wondered whether it could cure cancer? Didn’t think so. Nevertheless, the Chinese and Japanese have known for centuries that particular mushrooms can play a role in treating cancer, and some mushroom extracts have even been approved for clinical use in China and Japan. I hope to prove to you that mushrooms should be taken seriously as a rich source of potential pharmaceutical drugs. Lingzhi, also known as ‘reishi’ in Japan or Ganoderma lucidum to the scientific world, is a mushroom that had a reputation in ancient China for being the ‘mushroom of immortality’. Lingzhi extracts have been highly studied and found to contain a compound known as ganoderic acid, which belongs to a class of molecules known as triterpenoids. Ganoderic acid has a remarkable capacity to kill highly invasive metastatic cancer cells in vitro, whilst being less toxic to ‘normal’ human cells. It has multiple suppressive effects on cellular signalling pathways involved in tumour survival, growth and invasion of tissues. The cancer cells stop dividing and undergo programmed cell death. Recently there has been high interest in other natural and synthetic triterpenoids which also have anti-cancer effects. Lingzhi extracts contain another
class of molecule that may aid anti-cancer effects, beta-glucans. Beta-glucans are polysaccharides (branching sugar chains) found in the cell walls of all fungi. They do not directly kill cancer cells, but have been shown to stimulate the immune system to attack tumour cells more effectively. All mushrooms contain beta-glucans, but not all beta-glucans are equal. Large and highly complex betaglucans, such as those produced by lingzhi, may be particularly potent. Yunzhi (Trametes versicolor) is another mushroom famed for its beta-glucans, which in Japan were turned into a drug called Krestin. Krestin has been used in humans since 1970; it is well-tolerated and significantly improves survival in 70-97% of patients with cancers of the lung, stomach, ovary, and cervix. Krestin works best alongside standard chemotherapy or radiotherapy, in order to reduce their immunosuppressive side-effects by boosting the production of white blood cells.
Reishi has a reputation for being the ‘mushroom of immortality’
Why do fragments of fungal cell wall produce an anti-cancer effect? Well, the problem with the immune system is that it does not easily recognize cancer cells, as they produce the same proteins as normal human cells, but in different proportions. Additionally, advanced cancers tend to have developed mechanisms to evade immune detection or actively suppress the tumour-killing activity of cytotoxic T-cells and natural killer cells. Beta-glucans activate an immune response because they are foreign and not produced by human cells, and the result is proliferation and activation of cells involved in immunity. Therefore, the immune system is on high alert and much more likely to kill tumour cells. Drugs containing natural betaglucans have not been approved by the US Food and Drug Administration, despite their popular prescription in Japan. However, it is estimated that up to 83% of cancer patients use ‘complementary and alternative medicines’, such as medicinal mushrooms, most likely due to the failure of standard chemotherapy treatments. Western medicine, with all its advances, is still poor at curing most types of cancer. I believe that if medicinal mushrooms can improve survival with no toxic effects they should be embraced.
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FEATURE
Introspection:
How does it happen?
Leslie Bicknell
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ave you ever thought about thinking? Reflected on why you think or feel a certain way? If you have at least realized that you have a preference for, say, sugar in your coffee, then you have engaged in introspection - an “inspection” of your inner self. As far as we know, introspection is a uniquely human ability. It allows us to gain a deeper awareness of our actions. But what is going on in our brains when this happens? Until recently, this question has puzzled neurologists. “We want to know why we are aware of some mental processes while others proceed in the absence of consciousness,” said Steven Fleming, a cognitive neuroscientist, “There may be different levels of consciousness, ranging from simply having an experience, to reflecting upon that experience. Introspection is on the higher end of this spectrum. By measuring this process and relating
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it to the brain we hope to gain insight into the biology of conscious thought.” A team of researchers, led by Professor Geraint Rees and including Fleming from the University College London, conducted a behavioural study of 32 volunteers designed to reveal levels of introspection in individuals during decision-making. The variability found between participants was compared to brain structure using magnetic resonance imaging (MRI). A specific region of the brain appeared to be larger in those who could turn their thoughts inward and reflect upon their decisions, according to the paper published in the journal Science . This act of introspection, or thinking about your thinking, is a key aspect of human consciousness. However, there is extensive variation in peoples’ ability to introspect. This region of the brain, the prefrontal cortex (PFC) (located
directly behind the eyes), has previously been associated with planning complex cognitive behaviour, personality expression, decision-making, and moderating social behaviour. It is considered by neurologists to coordinate your thoughts and actions with your internal goals. The researchers discovered that the people who were more introspective had greater amounts of grey matter and neighbouring white matter in the anterior PFC. In other words, they had more neurons and neural connections in that region. Yet it remains a mystery how exactly introspection and the two different types of brain matter are related. If a person has a greater amount of grey matter in the anterior PFC, it doesn’t necessarily mean that they have greater introspective tendencies. The research does, however, show a correlation between the structure of grey and white matter and the various levels
We want to know why we are aware of some mental processes while others proceed in the absence of consciousness of introspection. Perhaps a comparison with our primate predecessors can give us some insight into this matter. What is the difference between our brain’s center for decision-making and that of an ape? When decisions are based on judgment rather than intuition, the brain must be doing something drastically different. The PFC may be one of the key parts of the brain that distinguishes the human race from other animal species. It is theorized that, as the brain has tripled in size over 5 million years of human evolution, the PFC has increased in size six-fold. Yet it doesn’t seem to be the relative size that makes it particularly special. MRI has recently been used to measure the relative size of the PFC in humans and all species of great apes. It was found that the relative brain size was almost the same in humans as in the great apes, including chimpanzees, bonobos, gorillas, and orangutans.
What is special about our PFC is that it contains larger amounts of white matter, composed of axons that communicate with other parts of the brain, thus providing greater connectivity between the PFC and the rest of the brain than in other species. So yes, we have more neurons there, but the intricate connections between those neurons and the rest of our brain seem to allow for introspection. The more precise and detailed biological processes behind this will require more research, but at least we now know where to look. An interesting manifestation of introspection is lucid dreaming. This is when you are aware you are dreaming while you are dreaming. This enables you to control the dream to some extent. One common way people train their minds to lucid dream is to make a habit of asking themselves if they are dreaming during the day. This is them trying to be more
introspective. Does this mean that we have some power to increase our amounts of white and grey matter in the prefrontal cortex? In the paper, researchers are still unsure about this, “Our present findings may reflect innate differences in anatomy, or alternatively reflect the effects of experience and learning. This raises the possibility of being able to “train” metacognitive ability by harnessing underlying neural plasticity in the regions we identify here.” By gaining insight into the nature of introspection on a neurological level, we can learn not just about how we think and train our minds, but also about psychological disorders and how to improve treatment for various mental illnesses. Consciousness: a mysterious labyrinth now with many hints, a map, and a flashlight.
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ARTICLES surgery, Sylvia claimed an intense craving for beer, chicken nuggets and green peppers, all of which she never liked before. She began to assume a masculine walk (peculiar for the dancer), started swearing in conversations, and for no apparent reason took up motorcycle riding at dangerous speeds, which was totally out of character. Sylvia even started having recurring dreams of a mysterious man. In her book entitled “A Change of Heart”, she recounted a dream where she kissed a boy thought to be named Tim L. and inhaled him into her. Upon meeting the “family of her heart” as she put it, Sylvia learned the name of her donor was in fact Tim L., and all of the changes she experienced closely mirrored that of Tim L. who strangely at the point of death had chicken nuggets in his pockets. Sylvia’s story quickly captured media attention and soon after, many other transplant recipients came forward with similar testimonies. The most striking example is that of an eight year-old girl who received the heart of a ten year-old girl. Post-surgery, she was consistently plagued with distressing dreams of an attacker and a girl being murdered. Her nightmares proved so vivid that even her psy-
Transplanting Memories?
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eorge Bernard Shaw once said, “All great truths begin as blasphemies.” In the realm of heart transplantation technology, none has posed greater uproar than the controversial concept of cellular memory. Cellular memory is the notion that the brain is not the only organ capable of storing memories. In fact, all living cells possess “memory”. Evidence for this has been found predominantly in heart transplant patients. Studies on cellular memory from transplant patients are often conducted by scientists with the aid of the hospital system which forbids the recipient to know or communicate with the donor’s family with most cases without the mention of names. On May 29th, 1988, Claire Sylvia received both the heart and lung of an 18 year-old man killed in a motorcycle accident. After the
chiatrist believed them to be genuine memories. As it turns out, the donor was a murder victim and as a result of the recipient’s violent recurring dreams, she was able to describe the horrifying incident and the murderer to such great detail that the police eventually apprehended, arrested and convicted the killer. Ongoing research has shown that neuropeptides and receptors previously known to exist exclusively in the brain have been discovered in places throughout the body, especially in major organs such as the heart. These neuropeptides are a means for the brain to communicate with other organs and for these organs to send feedback to the brain. However, little is known about whether these neuropeptides can store memory; due to the amount of peptides in the heart, there seems to be a strong correlation between the two. But if this were the case, then why don’t all patients go through this experience? There is no solid evidence that the reports are nothing more than coincidence and fantasy. Even so, the stories are intriguing and we should expect some serious investigation into the matter in the near future. Until then let’s keep an open heart.
Theories to debunk this phenomenon
Rhema Andrews
1. Hospital Grapevine Theory: Patients may be influenced by information unintentionally leaked by hospital staff during surgery whilst under anaesthetic. 2. The Drug Theory: The change of behaviour in patients could also be related to the high dosage of painkillers administered during the operation period. High dosages of drugs can cause changes in hormone levels leading to behavioural changes. 3. Life-Changing Experience Theory: The prospect of undergoing a heart transplant can cause patients to reflect on their lives. The sense of a second chance can lead them to make drastic changes after surgery.
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The Blood Crisis ‘‘Today, 2.5 million units of blood are given to patients in Britain annually.’’
Eleanor Bird
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n 1818, Dr. James Blundell conducted the first successful blood transfusion, initially to treat haemorrhage after childbirth. The demand for blood has since sky rocketed, amplified by conflicts and wars around the world. Today, 2.5 million units (450ml each) of blood are given to patients in Britain annually. However, the current system of blood donation and transfusion is riddled with difficulties. For example immune compatibility; type O negative blood is produced by just 7% of the population, but can treat 98%. Safety is paramount, but many developing countries still rely on paid donors and do not have access to reliable testing systems – blood transfusion is the second largest source of new HIV infections in Nigeria. Storage limitations also make it near impossible to have a stockpile of blood; platelets can only be stored for up to a week and red blood cells (RBCs) for 42 days when refrigerated. There is a cry for suitable and abundant alternatives to blood, but how much progress have we made? To combat these problems, blood substitutes are being explored. Most of these rely on cell-free haemoglobin, the protein in RBCs responsible for transporting oxygen. Haemoglobin-based oxygen carriers (HBOCs) can potentially be kept for up to three
years, and they allow for instantaneous full capacity oxygen transport. Another substitute type uses perfluorocarbon (PFC) particles that can reach oxygen-starved tissue, whereas conventional cells cannot. These substitutes may offer an alternative to those who refuse transfusions on religious grounds. Moreover, they do not contain antigens that cause immune incompatibility. Despite the promise of blood substitutes, they are also problematic. Fluosol DA20, the first PFC blood substitute to be approved for use by the Food and Drug Administration in 1989, was soon withdrawn due to limited efficacy. Clinical trials have shown that HBOCs may cause adverse effects such as pulmonary hypertension (high blood pressure in the arteries of the lungs) and low cardiac output (volume of blood pumped by the heart in a given time frame). The only HBOC currently in human use is Hemopure, which in 2001 was approved for use only in South Africa for acutely anaemic patients. New HBOCs are currently in development; whether these will be an improvement remains to be seen. Using stem cells may provide a better alternative. This involves growing RBCs from haematopoietic stem cells from the umbilical cord or bone marrow. The cells are
cultured, and an added cocktail of growth factors drives differentiation. The resulting RBCs have the same structure and haemoglobin content as normal cells and a similar life span. Importantly, stem cell blood does not carry the risks of infection and the supply could be adjusted to fit demand, particularly the supply of type O negative blood.The clinical feasibility of stem cell blood has recently been demonstrated. In 2011, it was reported that researchers at the Pierre and Marie Curie University in Paris extracted haematopoietic stem cells from bone marrow, cultured them into RBCs and injected them into a donor. The cell survival rate was normal and all indications suggest they are safe. The major obstacles to progress in this field are costs, time and ethical considerations. Production must be scaled so cells can be made rapidly and cheaply. It may take years to generate litres of blood from just a few stem cells, but there is reason for optimism; bioengineered embryonic stem cells can potentially generate one hundred billion RBCs from a single six well plate of cells. The future will see research into stem cells accelerate; disappointing results with oxygencarrier substitutes have made this production of bioengineered RBCs the most promising route.
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ARTICLES
Science fiction – a predictor of science fact Dan Titmuss
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fantastic science fiction writer called Arthur C. Clarke once said, “When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.” Science fiction films and books are often filled with things which make professional scientists cringe, to the extent that doing a science degree ruins a lot of films. We try not to notice, but at the back of our minds, it is always nagging away. Physicists note that the screams of an X-wing in Star Wars would be impossible to hear in a vacuum; “in space, no one can hear you scream” (thank you Alien), or that Superman catching Lois Lane at near terminal velocity would kill her in an even more brutal way than the ground would. As a zoologist, it makes me cringe when I see the non-venomous python or milk-
snake launch a deadly venomous attack at the main characters - just use venomous snakes, is it really that hard? But every so often, engineers and scientists watch a film and ask themselves if a fictional concept could become fact. Take the Star Trek ‘tricorder’, a device used (among other things) to diagnose any health problems in a patient. Although this seems like a mystical, far away fantasy, think about glucometers used by diabetic patients to measure blood sugar levels. Is this an early version of a tricorder? Recently a TED lecture (www.ted.com) mentioned a cash prize for the first person to come up with a diagnostic ‘machine’ that could rival a tricorder. Perhaps that isn’t all Star Trek has given us. When Stephen Hawking was shown the concept of ‘warp drive’ on a set of Star Trek, he joked “I’m working on that”. The list of innovations that have
The first spac e elevator would be built “about 10 years after everyone stops laughing”.
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been predicted continues: scuba diving (Jules Verne, who also predicted the moon landings extremely accurately), CCTV (the government taking inspiration from 1984), credit cards (H.G. Wells) and geosynchronous satellites, to name just a few. Geosynchronous satellites were first envisaged by Arthur C. Clarke. Now these satellites are possible, we can build on another theme of Clarke’s writing, space elevators. The idea of a space elevator involves attaching a cable extending from one of the geosynchronous satellites all the way down to Earth, creating an elevator which can take you all the way to space. The idea sounds ridiculous, but as long as a cable is strong enough (which is becoming possible through carbon nanotubes), it could actually be realised; an elevator, to space. Clarke also noted that the first space elevator would be built “about 10 years after everyone stops laughing”.
The victorious SpaceShipOne in flight
Perhaps unsurprisingly, monetary inducement prizes have the ability to greatly hasten progress in science and engineering.
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hen people hear the term ‘scientific prize’ they tend to think of Nobel prizes being bestowed upon scientists who have made a breakthrough discovery. But a whole separate category of cash prizes exists which are awarded for the first researchers to solve a predefined problem. These inducement prizes have been around for a long time. An early example, set by the British Parliament in 1714, asked for anyone who could devise a method for accurately determining a ship’s longitude. Another famous example was the Orteig Prize, a whopping $25,000 award initially offered in 1919 for the first daring aviator(s) to fly across the Atlantic from New York City to Paris. The challenge was finally completed in 1927 by Charles Lindbergh, a man who became an overnight celebrity for his daredevil solo flight. Aviation-related prizes are still relevant nowadays, although the frontiers have expanded greatly. The largest inducement prize in history was awarded in 2004; this was the Ansari X Prize, created to encourage a non-governmental organisation to design and launch a manned spacecraft to 100 kilometres above the earth’s surface, twice within two weeks. SpaceShipOne was the vehicle to complete this first private space flight, netting its creative team the very attractive sum of $10 million. As a testament
Just think of the money Erik Müürsepp
to the effectiveness of competitions such as these, the competing teams spent a total of more than $100 million to win the grand prize. The Ansari Prize is part of the larger X Prize Foundation which aims to bring about great benefit to all of mankind through similar large-scale competitions. The foundation’s board of trustees come from many walks of life and include people like Larry Page, CEO & co-founder of Google and James Cameron, the renowned director and explorer. The foundation currently offer prizes for technology which could accurately sequence 100 human genomes in ten days, at a cost of no more than $10,000 per genome. Also desired is a mobile device that would diagnose ailments in people at least as effectively as a real doctor would. Both these competitions come with a $10 million prize fund. Some clever ways to distribute award money have also been devised. The Methuselah Foundation, which is interested in extending
human lifespan, bestows the Mprize for research towards creating the world’s oldest mouse. The amount won is proportional not only to the current prize pool, but also to the margin by which the previous record is broken, thus ensuring that the fund is never exhausted. An inducement prize can even be set by an organisation not renowned for any scientific activity. The well-known animal rights organisation PETA has offered $1 million for the first scientist that succeeds in producing and marketing in vitro meat; this is grown in a lab environment from animal stem cells, avoiding the killing of billions of animals every year and reducing the impact that meat production has on the environment. PETA may not have to wait long for this to become a reality, as a research group in Maastricht University has promised to create the first test-tube hamburger by autumn of this year.
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FEATURE
How essential is your Immune System?
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Sophia Ho
You may be sat focused in a lecture, exercising in the gym, snacking in your lunch break or simply just relaxing. Whatever you are doing your immune system will be continuously fighting to protect your body against foreign material which threaten to cause you harm.
he influence of the immune system on our health and physiology is not only imperative but incredibly widespread. It is often known for being an essential tool for dealing with diseases by ensuring that agents which damage and disrupt bodily functions and systems are cleared, neutralised, or at least prevented from spreading to the rest of the body. These agents are usually in the form of pathogens, i.e. harmful microorganisms, including bacteria, fungi, parasites and viruses. However, the immune system is also responsible for many other aspects of mammalian disease, including inflammation, allergic reactions, and, when incorrectly regulated, even the creation or exacerbation of an ailment. This can result in inflammatory diseases, autoimmune disorders, and even cancer. The immune system comprises of several pathways containing numerous cell types. As well as their individual, independent roles, which differ between cell types, they are also all able to act collaboratively in order to neutralize
disease-causing threats. Each cell of the immune system will have gone through early development processes to ensure that they only recognise foreign material (nonself) as a threat, rather than cells of the body (self). This avoids an immune response against your body’s own cells. The two major branches within the immune system are the innate and the adaptive immune responses. These are activated once foreign material successfully breaches the basic physiological and chemical defence barriers of the body, such as the skin, and enters mediums such as the blood or the lymph (the network of extracellular fluid).
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The innate immune response consists of cells such as mast cells, phagocytes, natural killer cells (NK cells), basophils and others. Their response is non-specific, meaning they are able to recognise a wide range of microorganisms using pattern recognition receptors (PRRs) on their cell surfaces, which recognise antigens (molecules on the surface of pathogens that activate the immune system). Damaged cells (wounds or burns), or cells under stress (infections), can also be detected using the same receptors, inducing innate immune cells to release chemicals that are responsible for inflammation, known as cytokines. The effects of
Cells of the immune response
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inflammation include the attraction of phagocytes to the site of infection and local vasodilation of blood vessels, allowing more cells of the immune system to access the area of infection or damage. The innate system doesn’t develop any kind of ‘memory’ towards pathogens it encounters, no matter how many times a particular pathogen is encountered, the innate immune response will react identically on each encounter. The adaptive or acquired immune response, however, does provide a memory mechanism in order to generate responses that are specific to pathogens that the body has already encountered, mediated by ‘memory cells’. These enable stronger responses to be elicited on subsequent encounters with the same pathogens. Other cells of the adaptive immune response, B lymphocytes and T lymphocytes, are also able to take action on new pathogens, using antibodies and receptors, respectively, on their cell surfaces. Cells of the immune system collaborate by releasing chemical factors which activate other immune cells, enhancing the immune response to deal with threats at optimal levels. These include interleukins, interferons, cytokines and complement, which all function
differently and against different types of pathogens, in order to clear them effectively, as well as providing a complex and thorough means of communication between all the cells of the immune system, bridging the innate and adaptive immune responses. The immune system clearly has a significant role in the maintenance of health. However, many pathogens have established mechanisms with which to evade or counter the immune response through antigenic variation and evolution, even during disease
progression. Compared to the everchanging characteristics of microorganisms, particularly bacteria and viruses, the immune system is relatively slow when it comes to adapting and effectively responding to developing pathogens. Nevertheless, it is vital for the management of diseases and disorders that can take place within the body, and its many aspects continue to be the subject of intense research.
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ARTICLES
W
as your hair a little longer this morning? Wake up a tiny bit taller? Hopefully, although you may be unaware of these things happening, the answers should be ‘yes’. Driving these processes is a group of highly complex macronutrients called proteins. Eating the correct amount of protein every day is fundamental to our health and survival, and protein comes from a variety of sources: meat, green vegetables, fruit, eggs, bacteria, fungi and algae. Wait! Bacteria, fungi and algae? Anybody have these on toast for breakfast? These may sound like unusual meal time choices, but one day they may be the future source of global protein. This year, the global human population reached 7 billion; a commendation to the advances in healthcare, sanitation and education, however all these extra fleshy machines consuming vast amounts of resources comes at a cost. Crops and livestock are being produced in larger quantities every year. However, any good mathematician will remind us that this resource increase is linear, whilst population increase is exponential; in other words, food production simply cannot keep up with us. There are around 1 billion people ‘hungry’ on Earth today. However, globally 1/3 of edible food is wasted, so is this just a question of unequal distribuPrevelance of undernourishment in developing countries (2005-07)
Very high (35% and above) High (25-34%) Moderately high (15-24%) Moderately low (5-14%) Very low (below 5%)
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Microbes that Feed the World Louise Brown
tion and greed? This is probably a factor, but the issue remains to provide for those in the third world who can only afford to live by exporting most of the food they grow to richer countries like the UK. The ‘global protein crisis’ refers to the fact that although people in the third world need more protein from animal sources, rearing livestock is an inefficient conversion of energy with much land wasted growing animal feed which could be growing human food. There are many potential solutions in discussion; one could incorporate both reducing waste and biotechnology - this is extracting protein from microorganisms (bacteria, fungi and algae). This protein is termed ‘SingleCell Protein’ (SCP). Microbes could be cultured on agricultural wastes and the proteins produced during their natural growth could be extracted, dried and used as a human dietary supplement. This seems a great idea; reusing waste to produce useful products to help alleviate the global food
crisis. Simple technology is involved; the last time you had a pint or a glass of wine, production of this involved yeast fermentation. Quorn products are also produced from fungal biomass. SCP has many attractive benefits; the high protein content of the microorganisms combined with their high rate of multiplication and low land requirements seems to be a very efficient source of lots of protein. The microbes grow on a huge range of substrates, bringing the costs down for supplying these, as wastes can simply be used. The process is also climate-independent, certainly an advantage in modern times. Unfortunately, some microbes produce toxins which are detrimental to human health in large amounts. This problem can be avoided by using strains with no toxin production, or genetically engineering microbes. Another issue is cost; producing protein in this way has to be economically viable, especially if it’s targeted at the developing world. Currently, the costs of production and distribution of microbial protein could only be met by large rich corporations. Any new ‘food’ also has to be accepted by the consumer, if it doesn’t taste or look good we aren’t going to eat it! Making microbial protein palatable is proving a challenge for food technology companies, but watch this space. A combination of solutions will be required, to feed all our extra mouths, and biotechnological solutions will certainly have their part to play.
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THE PERILS OF PUBLICISING SCIENCE
cience is fantastic. Groundbreaking life-changing research shaping our lives and futures: it’s thrilling, exciting and invigorating. It’s a commonly held view amongst scientists that it is of utmost importance to educate the public on what we know and get them enthusiastic about the latest discoveries. More informed decisions are better ones, areas of public interest are awarded more funding. But how can we so nonchalantly omit the counter argument in considering our responsibility to society? Knowing more about food and our bodies is supposed to make the nation healthy, but this is not the case. Broadcasting the latest research into the causes of obesity may amplify the problem by removing the responsibility of the individual to pursue a healthy lifestyle. This research includes how hormones, the brain and genes can attribute obesity to predetermined biological factors. Newer is better, so the old ways of healthy eating and exercise become unavailing in the eyes of the overweight and they can blame fixed characteristics. The government’s £75 million ‘Change for Life’ campaign was backed by £200 million of commercial and media funding; so that’s £275 million undermined by sentiments like “an overweight person is overweight because of their hormones” and “obese people’s brains differ from the brains of normal weight individuals”, before counting strategies imposed by other charities and health organizations. How is this vortex of wasted cash beneficial to the person on the street? Can it be argued that it’s advantageous to shift public focus to the option of a gastric by-pass from the power of will?
Gemma Hallam
The old MMR/autism misunderstanding emphasizes that we are all too keen to put about research without first considering its social influence. Each time the story re-emerges we are abhorred again at how a study of just 12 participants (5 of which had “pre-existing development concerns”) could have had grounds to cause international hysteria. There are numerous cases in which health advice has been issued to mothers based on flimsy evidence. Article after article dishes out guidance on pregnancy and child rearing, stating but vastly under-emphasizing, ‘‘more research is needed”. But how can conditions such as cancer, neurological development and multiple sclerosis, be advised upon with such shaky foundations in such sensitive circumstances? How do we let inadequate research become sprawled over the media without first calculating the impact on society? There is an abundance of research relating a mother’s stress levels to health, development and behavioural problems in children. This is strongly supported evidence, yet we
are quick to forget it when another study hints there may be a tenuous link between drinking tap water or using plastic bottles and damaging child development. There is so much conflicting advice there is no measure of damage that could be caused by irresponsible reporting. Although the intention of communicating science is largely in the interest of society, it is easy to see how it could be harmful. It is compelling to consider that as a source of funding, scientists have a duty to responsibly report to the taxpayer and explicate their findings. Ultimately, the problem lies in dumping information into the public domain. Interpreting information that is not in our field of expertise can also lead to misconceptions. It is not new research that is at the domain of this responsibility debate, but the context in which it is framed. If crucial details, for example the power of a healthy lifestyle or that evidence is currently unsubstantiated is allowed to go understated and neglected, the overall message to the public is irresponsible, and that is what we must consider.
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FEATURE
Sh uld bi logical sex be c nsidered neur logical destiny? M
ale and female brains are often regarded as two very different organs. In the book ‘The essential difference’ Simon Baron-Cohen suggests the female brain is better suited for empathising (e.g. noticing other peoples’ emotions) and the male brain better for systemising (e.g. reconstructing electrical appliances). It is often assumed neurological sex differences are responsible for stereotypical behaviour. So are there differences between the neuroanatomy and neurophysiology of males and females? And if there are, are these differences determined with sex, at the point of fertilisation or is the differing treatment of men and women in society responsible for initiating neurological changes? Biological sex is determined during fertilisation. However, during the initial stages of gestation only the X sex chromosome inherited from the mother is activated, causing the foetus to initially develop as a female. It’s during the eighth week of pregnancy that the child’s sex is confirmed by the activation of the paternal sex chromosome (X or Y). A Y
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Rachel Cole chromosome initiates a surge of androgens thought to stimulate the formation of the testes and a characteristically male brain, causing sex and gender to correspond. This is referred to as the foetal fork. So what neuroanatomical differences could be responsible for the differing systemising and empathising abilities of the sexes? Jill Goldstein and colleagues performed MRI scans on the brains of forty-eight healthy adults. The 3D images of forty-five different brain regions were analysed. Results showed women had a comparatively larger limbic system, a part of the brain related to emotion processing, possibly explaining their tendency to be better empathisers. In 2005 Richard J. Haier observed relative proportions of grey and white matter in brain regions associated with intelligence. Haier and his team found women had a larger proportion of white matter and males a larger proportion of grey matter in these particular areas (conflicting with Goldstein’s research). White matter is associated with transporting information to other areas of
the cortex whereas grey matter is associated with local processing of information. Local information processing is useful when carrying out systemising tasks such as solving maths problems. It has been suggested that males’ greater proportion of grey matter could be responsible for their better systemising abilities relative to the average woman. Likewise it has been considered that the higher proportion of white matter in females could be related to their generally superior linguistic aptitude.
d
Why it’s not so straight forward The first problem is that neuroplasticity makes it difficult to determine whether any existing neurological differences between men and women are genetically innate or socially developed. Neurons don’t divide and replicate so until recently it was assumed no new ones appeared after birth. However Joseph Altman (1962) discovered new neurons were formed by stem cells throughout life via neurogenesis. In addition to the formation of new cells, neural pathways can be altered. The more these pathways and connections are utilised the more they are strengthened. Connections that remain unused will weaken. This mechanism is vital for learning and memory. Secondly, many believe sex discrimination is an issue of the past but stereotypes are still highly influential. ‘Stereotype threat’ is a term used to describe ‘being at risk of confirming, as self-characteristic, a negative stereotype about one’s group’ Steele & Aronson, 1995. The power of the stereotype threat is demonstrated by a study comparing the maths test performance of women after reading different articles. The women who had read an essay claiming there are genetic reasons for men’s better maths ability, performed worse than equally able women who’d read an essay claiming men’s extra effort was the reason for their better maths results. What’s also interesting is that the women who’d read a neutral article performed almost as badly as those who’d read the genetics argument. This suggests the
stereotype threat is evident unless actively removed and should be considered when testing for gender differences. These results imply that neurological differences between the sexes are partially caused by social factors. A third problem is misleading research. Although the foetal fork is a widely trusted theory those who have analysed the methods used to measure foetal testosterone have grown sceptical. The hormone level experienced by a developing baby can be measured by various techniques. Amniocentesis, the process of extracting amniotic fluid provides a sample which can be tested for hormones such as testosterone. However, how well the hormone concentration in the amniotic fluid correlates with the hormone levels of the foetus’ blood is unknown. Another method measures the hormone levels of blood samples from the pregnant mother. However there is no evidence to suggest
maternal testosterone is higher in women carrying males than those carrying females. This suggests that there is no direct relationship between maternal testosterone levels and the androgen exposure experienced by the foetus. Therefore these methods do not provide reliable evidence to assume that sex chromosomes determine the level of gender associated hormones a baby is exposed to in the womb. At present there appears to be no significant benefits that would result from regarding biological sex as neurological destiny but many disadvantages. It’s probable that sex stereotyping in this way would increase sex inequality, decrease mutual understanding and restrict right of choice. Therefore to consider biological sex as neurological destiny would be scientifically, politically and morally flawed.
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FEATURE
CAREERS IN SCIENCE
Perhaps reading SYNAPSE has inspired you to aim for a career in science – here are a few directions that this dynamic and exciting sector can take you. Research
Whether it be for medical, industrial or commercial purposes, remember that this exciting area does involve long term commitment with projects lasting years in some cases, often with long periods of stalled progress and long slogs behind lab benches, in the field, or waiting for funding. However the positive implications for society and recognition can be worth it. Research is an international collaboration so you may find your lab bench can be in any corner of the globe!
Louise Brown Education
The usual way for graduates to head for a career in teaching is to study for a postgraduate certificate in education (PGCE). This lasts for 1-2 years and qualifies you to teach in primary or secondary schools.
Academia
University-based academic careers can follow from Masters or PhDs. Faculty positions like lecturing are hard to come by, and the mantra ‘publish or die’ is a given. However, such a career is highly thought-of and can lead to a long term and very rewarding job. Try talking to your tutor or lecturers for advice.
Conservation and Environment
There are many different routes into a career in conservation and the environment, and if it’s your thing you can start right now; volunteering for a local trust or organisation will give you further insight into what such a job may involve and would look great on your CV. Work in conservation can take you all over the world, and environmental work is currently an expanding sector (think climate change, renewable energy, world food supply…) so both are exciting directions to head in if you’re enthusiastic about the natural world. Check out www.ecojam.org or www. greenvolunteersbristol.co.uk for local volunteering opportunities to get experience in this sector whilst at University.
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Science Communication
Science communication is fundamental to the way science works; research scientists need to communicate in the lab, through journals and at conferences for science to progress. Scientists also need to communicate with the public, through press releases and media such as TV and radio to keep interest alive. Careers in science communication include journalism, journal and medical writing, TV and radio presenting or producing, education, book writing and work in visitor attractions such as museums; anything that gets scientific knowledge out there. With the BBC Natural History Unit right here in Bristol, why not see what voluntary work you can get there? There are plenty of opportunities within the university to get media experience too - all the contributors to SYNAPSE are students!
Business and Enterprise
Enterprise is an important part of science, and allows innovations in science to have an impact on society, for example setting up a new company to market a new drug, or a new agricultural method. There are other ways of being involved in the business side of science; from patent attorneys to licensing managers to company roles in research institutes, any business job you can think of exists in the science sector. Scientific sales offers another possible career choice; having a scientific background means you can discuss scientific and technical equipment validly with scientists - it’s much easier to convince them to spend some of their precious research grant on your new neutronparticle-smasher5000 if you actually know what it does…
The above are just a few examples of the areas you can work in the science sector; the real list of possibilities is innumerable, with opportunities in forensics, law, politics and many more available to you. Here is a directory of contacts and services to help you research and find your career niche.
Useful Links Bristol University Careers Sevice:
http://www.bris.ac.uk/careers/ advice
Graduate Prospects:
‘Prospects’ is the UK’s official graduate website. It’s pretty general, but a good starting point. http://www.prospects.ac.uk/
Find a PhD: This is one of the main websites for advertising postgraduate research degrees, studentships and scholarships. http://www.findaphd.com/ They also have a sister site for finding Masters courses http://www.findamasters.com/ There are hundreds of graduate sites; try a Google search and sign up to a few to get a good idea of the job market. And good luck job hunting!
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