There is ‘liminal space’ between cellular life and death. Despite the fact that they are often thought of as oxymoronic, it is not as straightforward. Many have grappled to denote the moment of death for humans: Is it when the beating of the heart no longer occurs? When breathing stops? A lack of detectable activity? Divergent answers arise as death is a process, and by definition, not an irreversible one.
In regard to cells, predominantly it is assumed that once the cells pass critical checkpoints, the death process is irrevocable. Such checkpoints include condensation of nucleus, collapse of DNA, disintegration of the mitochondria and cell shrinkage. Moreover, these events are often intentional. An essential component of life is programmed cell death, with over 20 forms proposed. Among these, apoptosis is the most notable and well-studied due to its regulatory mechanisms in cell suicide, and crucial roles in embryonic development, maintaining a balance of cellular multiplication and regulating internal conditions (homeostasis) by eradicating the undesired, faulty or dangerous cells in the body.
Apoptosis in Greek is defined as ‘falling’ and it expedites the habitual turnover of cells, analogous to leaves falling from a tree in autumn. A number of triggers are involved in apoptosis, but at length they activate a decisive group of ‘executioner’ proteins named caspases. These enzymes, by cleaving hundreds of various types of proteins within a cell, inflict destruction in cellular targets, attack structural proteins and deconstruct the cytoskeleton, resulting in cell shrinkage to blebs and die.
With all this, dubiety also follows. The fence which segregates life and death is porous even at the degree of cells (the rudimentary units of life). A growing body of evidence have recently demonstrated that cells that are believed to be dead or terminal are able to revive themselves, or somewhat revive, hence reverse apoptosis when under the right conditions. This phenomenon is referred to as anastasis (Greek for ‘rising to life’) and can occur in vitro and in vivo.
A significant role that anastasis plays involves the maintenance of differentiated cells that are difficult to recoup, such as neurons and cardiomyocytes. In this way, anastasis can counter many of the complications resulted by apoptosis. A variety of degenerative diseases, such as Alzheimer and Parkinson, are associated with apoptosis not functioning correctly. This is because protein aggregation can activate an enzyme that triggers apoptosis, resulting in the death of neurons and loss of brain function.
However, if we rival apoptosis to the demolition of buildings, the detrimental effects that arise when anastasis takes place can be also understood. The caspases involved in the breakdown of cellular structures are somewhat like demolition workers destroying buildings. If someone decides after: “I don’t want it to be destroyed, please rebuild it.” Then, the damage has to be repaired, but this process of restoring may go wrong. You won’t have a complete replica of the original. Therefore, when anastasis takes place, the resurrected cells may bear chromosomal abnormalities and acquire mutations. This will engender a multiplier effect where particular mutations will cause unchecked cell growth and proliferation. Henceforth, this revival process may trigger normal cells to become carcinogenic, by gaining new mutations and transmuting into more hostile and metastatic cancers. In this way, cancer cells are said to employ anastasis as a way to ‘cheat death’ and use it as an escape tactic to survive cell- death- inducing anti-cancer therapy (e.g. chemotherapy and radiotherapy).
The correlation between anastasis and cell regeneration, rise of disorders and cell death decision is yet to be elucidated, as additional research is required to confirm a direct link. Ultimately, if there truly is a correlation, the resurrection of cells could increase awareness into multidisciplinary fields of science that supplement our understanding in the control of cell survival and destruction. Furthermore, it could provide insight into identifying novel analeptic approaches for brain damage, cancer, injury to tissue and moreover regeneration medicine by meditating the reversibility of apoptosis.

​Introduction:
 
As a second patient is seemingly cured of HIV after receiving a stem-cell treatment for his (Hodgkin lymphoma) cancer, it begs the question of whether HIV is ‘incurable,’ as we have always assumed. This article will endeavour to explain how HIV and AIDS affect the human body, how Adam Castillejo was ‘cured’, and what all this means for the future of modern medicine.
 
HIV:
 
HIV stands for the human immunodeficiency virus. It is a virus that attacks cells that would normally help the body fight infection (CD4 helper cells), making a person more vulnerable to other infections and diseases. CD4 helper cells are a subset of white blood cells that do not neutralise infections, but rather trigger the body’s response to infections.
 
There are 7 steps that HIV follows to multiply in the body. These are illustrated in the picture below. The process begins when HIV encounters a CD4 cell. The 7 steps in the HIV life cycle are

1. Binding. HIV binds to receptors on the surface of a CD4 cell.
2. Fusion. The HIV envelope and the CD4 cell membrane fuse (join together), which allows HIV to enter the CD4 cell.
3. Reverse Transcription. Inside the CD4 cell, HIV releases and uses reverse transcriptase (an HIV enzyme) to convert its genetic material- HIV RNA- into HIV DNA. The conversion of HIV RNA to HIV DNA allows HIV to enter the CD4 cell nucleus and combine with the cell’s genetic material- cell DNA.
4. Integration. Inside the CD4 cell nucleus, HIV releases integrase (an HIV enzyme.) HIV uses integrase to insert (integrate) its viral DNA into the DNA of the CD4 cell.
5. Replication. Once integrated into the CD4 cell DNA, HIV begins to use the machinery of the CD4 cell to make long chains of HIV proteins. The protein chains are the building blocks for more HIV.
6. Assembly. New HIV proteins and HIV RNA move to the surface of the cell and assemble into immature (non-infectious) HIV.
7. Budding. Newly formed immature (non-infectious) HIV pushes itself out of the host CD4 cell. The new HIV releases protease (an HIV enzyme). Protease breaks up the long protein chains in the immature virus, creating the mature (infectious) virus.

Not only does HIV attack CD4 cells, but it also uses the cells to make more of the virus. HIV destroys CD4 cells by using their replication machinery to create new copies of the virus. This ultimately causes the CD4 cells to swell and burst. Once the virus has destroyed a certain number of CD4 cells and the count drops below 200, a person will have progressed to AIDS.
 
You can get or transmit HIV through specific activities only. Most commonly, people get or transmit HIV through sexual behaviours and needle or syringe use. Only certain fluids- blood, semen, rectal fluids, vaginal fluids, and breast milk- from a person who has HIV can transmit HIV. It can also be transmitted from mother to baby during pregnancy via the placenta.
 
AIDS:
 
AIDS is the acquired immune deficiency syndrome. It is the name used to describe a number of potentially life-threatening infections and illnesses that happen when your immune system has been severely damaged by the HIV virus. Many people often confuse HIV and AIDS- HIV causes AIDS. HIV destroys CD4 T cells- white blood cells that play a significant role in helping your body fight disease. The fewer CD4 T cells you have, the weaker your immune system becomes. You can have an HIV infection, with few or no symptoms, for years before it turns into AIDS. AIDS is diagnosed when the CD4 T cell count falls below 200, or if you have an AIDS-defining complication, such as a serious infection or cancer. Thanks to better antiviral treatments, most people with HIV today don’t develop AIDS. Untreated, HIV typically turns into AIDS in about 8-10 years. AIDS only occurs once your immune system has been severely damaged and as mentioned before, is only diagnosed once the CD4 T cell count falls below 200, or if you have an AIDS-defining complication.
 
TREATMENT:
 
Antiretroviral medicines are normally used to treat HIV. They work by stopping the virus replicating in the body, allowing the immune system to repair itself and preventing further damage. These come in the form of tablets, which need to be taken every day. HIV is able to develop resistance to a single HIV medicine very easily, but taking a combination of different medicines makes this much less likely. On top of this, there are some people who are actually naturally resistant to HIV. CCR5 is the most commonly used receptor by HIV-1- the virus strain of HIV that dominates around the world- to enter cells. But a small number of people who are resistant to HIV have two mutated copies of the CCR5 receptor. This means the virus cannot penetrate cells in the body it normally infects. Researchers say it may be possible to use gene therapy to target the CCR5 receptor in people with HIV. Adam Castillejo was the second patient to be cured of HIV. He received a stem-cell treatment for a cancer (Hodgkin lymphoma) he had, and this rendered him virus-free. This is because the donor of the stem cells had the uncommon gene that gives them and now Mr Castillejo protection against HIV.
 
STEM CELLS:
 
In order to understand how the phenomenon of Mr Castillejo becoming HIV free came about, it is important to look more closely at how stem cells work. Stem cells are special human cells that have the ability to develop (differentiate) into many different cell types, from muscle cells to brain cells. In some cases, they also have the ability to repair damaged tissues. Stem cells are divided into two main forms- embryonic stem cells and adult stem cells. The embryonic stem cells used in research today come from unused embryos resulting from an in vitro fertilisation procedure that are donated to science. These embryonic stem cells are pluripotent, meaning they can turn into more than one type of cell.
There are two types of adult stem cells. One type comes from fully developed tissues, like the brain, skin, and bone marrow. There are only small numbers of stem cells in these tissues, and they are more likely to generate only certain types of cells. For example, a stem cell derived from the kidney will only generate more kidney cells. The second type is induced pluripotent stem cells. These are adult stem cells that have been manipulated in a lab to take on the pluripotent characteristics of embryonic stem cells. Although induced pluripotent stem cells don’t appear to be clinically different from embryonic stem cells, scientists have not yet found one that can develop every kind of cell and tissue.
The only stem cell currently used to treat disease are hematopoietic stem cells- the blood cell-forming adult stem cells found in the bone marrow.
 
Stem cell transplants are used currently in the treatment of cancer. In a typical stem cell transplant for cancer very high doses of chemotherapy are used, sometimes along with radiation therapy, to try to kill all the cancer cells. This treatment also kills the stem cells in the bone marrow. Soon after treatment, stem cells are given to replace those that were destroyed. These stem cells are given into a vein, much like a blood transfusion. Over time, they settle in the bone marrow and begin to grow and make healthy blood cells. This process is called engraftment.
 
There are two main types of stem cell transplants.
 
Autologous stem cell transplants are when the stem cells come from the same person who will get the transplant. In this type of transplant, your own stem cells are removed, or harvested, from your blood before you get treatment that destroys them. Your stem cells are removed from either your bone marrow or your blood, and then frozen. After you get high doses of therapy, the stem cells are thawed and given back to you. One advantage of autologous stem cell transplant is that you’re getting your own cells back. You do not have to worry about the new stem cells (engrafted cells) attacking your body, or about getting a new infection from another person. But there can still be graft failure, which means the cells don’t go into the bone marrow and make blood cells like they should. A disadvantage of an autologous transplant is that cancer cells may be collected along with the stem cells, and later put back into your body. Another disadvantage is that your immune system is still the same as it was before the transplant. As the cancer cells were able to escape attack from your immune system before, they may be able to do so again. To help prevent this, some places treat the stem cells before giving them back to the patient to try to kill any remaining cancer cells- this is called purging. Again, this has problems because some normal stem cells can be lost during this process. This may cause your body to take longer to start making normal blood cells, and you might have very low and unsafe levels of white blood cells or platelets for a longer time, increasing risk of infections or bleeding problems.
 
Allogeneic stem cell transplants are when the stem cells come from a matched related or unrelated donor. In the most common type of allogeneic transplant, the stem cells come from a donor whose tissue type closely matches the patient’s. Blood taken from the placenta and umbilical cord of new-borns is a newer source of stem cells for allogeneic transplant. Called cord blood, this small volume of blood has a high number of stem cells that tend to multiply quickly. But the small volume normally does not contain enough stem cells for large adults, so is mostly used for children and smaller adults. A positive to this type of stem cell treatment is that the donor stem cells make their own immune cells, which could help kill any cancer cells that remain after high-dose treatment. This is called the graft-versus-cancer effect. Also, the donor can often be asked to donate more stem cells or even white blood cells if needed, and stem cells from healthy donors are cancer-free. Cons- the transplant might not take; the transplanted donor stem cells could die or be destroyed by the patient’s body before settling in the bone marrow. Also, the immune cells from the donor may not just attack the cancer cells- they could attack healthy cells in the patient’s body. This is called the graft-versus-host disease. There is also a very small risk of certain infections from the donor cells, but as donors are tested before they donate, this is rare. A higher risk comes from infections you had previously, and which your immune system has had under control. These infections may surface after allogeneic transplant because your immune system is suppressed by medicines called immunosuppressive drugs. Such infections could cause serious problems, if not death. 
 
Of course, this all brings up the question of why can we not use stem cell transplants to cure all HIV patients? The answer is that it would not be possible to find enough genetically matched bone marrow donors with the naturally occurring genetic mutation to treat the 33 million people with HIV, even if that was desirable, safe and ethical. Also, most people with HIV already have very compromised immune systems, and so carrying out stem cell transplants would carry a significant risk, which may not be outweighed by the benefits.   
 
GENE THERAPY:
 
A lot of research has gone into the potential of using gene therapy for treating and preventing diseases in general, and specifically for HIV. Gene therapy is an experimental technique that uses genes to treat or prevent disease. In the future, this technique may allow doctors to treat a disorder by inserting a gene into a patient’s cells instead of using drugs or surgery. There is research into several approaches to gene therapy, including:
- Replacing a mutated gene that causes disease with a healthy copy of the gene.
- Inactivating, or ‘knocking out’ a mutated gene that is functioning improperly and causing unwanted consequences.
- Introducing a new gene into the body to help fight a disease.
Gene therapy is a promising treatment option for a number of diseases, including inherited genetic disorders, some types of cancer, and certain viral infections. However, the technique is risky and is still under study to make sure that it will be safe and effective. Gene therapy is currently being tested only for diseases that have no other cures.

Gene therapy is promising in helping cure HIV because people who are naturally resistant to HIV have two copies of the CCR5 receptor due to a random mutation. Gene therapy could be used to give people the second mutated copy of this receptor if they target the CCR5 receptor, hence, curing people of HIV. However, gene therapy is still a controversial technique, and whilst many believe that it will become a staple of 21st century medicine, experts say society will be better served if medical researchers proceed slowly and prudently. Therefore, it is likely to be decades until gene therapy becomes normalised in modern medicine. And for specific treatments, such as this supposed HIV cure, many years of testing, clinical trials and waiting for approval would have to pass before the treatment becomes available.

​Robots have always been lurking at the back of directors’ heads. From The Terminator of 1984 to Wall-E of 2008, robots may have evolved, but they remain the turn-to option for a merciless villain ready to take over the world or end humanity as we know it. In this article, I will be covering 3 different movies with 3 different types of robots with a similar motive.
​
My first movie is 2001- A Space Odyssey. Released in 1968 and directed by Stanley Kubrick, the main antagonist is more an artificially intelligent software than a robot. In case you aren’t familiar with this movie, it’s about a space quest to go to Jupiter to find what a monolith was aiming at, run by HAL 9000, the AI software. His increasingly bad behaviour forces two of the astronauts, Bowman and Poole to disconnect HAL. By lip reading their private conversation, HAL turns Bowman back into a foetus and kills Poole and the rest of the crew. While being disconnected, HAL explains that his secret mission was to kill all the crew members. This movie is the 7th earliest about robot, setting the example that robots are ordained to kill us all, and is a curse covered by a blessing.

My second choice is Wall-E. This movie, in short is about a space programme to evacuate humans from earth and make it a better habitat. This movie is full of robots, but I would like to focus on Auto, the artificially intelligent steering wheel. He takes over (unofficially) as the captain of the mission and turns a 5-year plan into a 700-year plan. His mission objective to never return to earth- A113, and he does anything to keep to this. This shows how helpful AI can turn on humanity and enslave us. There is also a striking resemblance between HAL and Auto - both are the head of a mission in space with a secret twist which affects humans. They also have a similar appearance - white with a red light in the middle. This could just be a nod to Kubrick by Disney, as they usually include cannon. However, it could have a deeper meaning… what if HAL had been restored generations after the first, unknown of the harm caused. That, really, is for you to ponder over.

My third and final choice is Big Hero 6. This Disney animation, in a nutshell, is about a healthcare robot, Baymax which makes friends with his dead creator’s younger brother, Hiro. He and his friends team up to uncover a mystery of microbots, small metal pieces, when put together forming a larger structure. Instead of talking about the antagonist, I am going to explore Baymax, the robot who is always willing to help. He helps those in need, and without spoiling the suspense too much, when programmed to be destructive, unlike our two other antagonists, Baymax uses his new skills to save people from danger, not to put people in danger. Baymax also shows a sense of understanding, which neither HAL nor Auto did. When his microchip is about to be replaced by Hiro, Baymax plays a video showing his elder brother struggling to create him. This warns Hiro not to make too much changes as the robot has taken shape due to someone else’s tireless effort.
​
In essence, most robots in movies are considered more of a bane than a boon, yet some always go out of their way to help. It is also interesting to see how robots and AI are shown to have two faces, one to help and one to destroy, yet this does not mean that they are decisively shady.

By Anagha Sreeram, 8C

By Charlotte Fox, 9L

In collaboration with the STEAM magazine and international women’s day on 8th March, the following article brings light to a huge scientific breakthrough for cancer research led by a female scientist.
Dr Eva Ramon Gallegos, a Mexican scientist from the National Polytechnic Institute, and her primarily female team (pictured left) have reportedly found a complete cure for human papillomavirus (HPV). The cure would help to prevent the spread of cervical cancer and Dr Ramon Gallegos claims to have eliminated the virus in 29 patients infected with HPV which is an outstanding achievement regarding the fact that cervical cancer is the fourth most common cancer in the world and is becoming a leading course of deaths among female cancer patients.
A report states that a team of researchers led by Dr Ramon Gallegos treated the 29 patients diagnosed with HPV with non-invasive photodynamic therapy (PDT) which “is a treatment that involves using a drug, called a photosensitizer or photosensitizing agent, and a particular type of light to treat different areas of the body” according to their report.
Dr Ramon Gallegos has been researching the effects of PDT for over 20 years to cure cancers such as breast and melanoma. She treated 420 patients in Oaxaca and Veracruz, in addition to 29 HPV patients in Mexico with PTD, which had promising results as PTD was able to eradicate the virus in the patients.
The treatment was 64.3% successful in women with both HPV and lesions but eradicates 100% of those tested who carried HPV without premalignant lesions of cervical cancer.
Moreover, what makes this accomplishment more impressive is that the treatment has no side effects and does no damage to the body at all.

“Unlike other treatments, it only eliminates damaged cells and does not affect healthy structures. Therefore, it has great potential to decrease the death rate from cervical cancer,” – Dr Ramon Gallegos, Radio Guama report.

For more information you can visit; https://www.sciencedaily.com/releases/2018/12/181218100404.htm

​Humans have looked out at the stars and planets for millennia, but it is only with the advent of flight that the dream of leaving our planet has become even remotely possible. The first human space flight by the soviet citizen Yuri Gagarin in 1961 was relatively quickly followed by the US moon landing in 1969. However, progress since then has been confined to near Earth orbit. The Cold War, which spurred the space race, had ended by the late 1970’s and commercial usage of satellites and near- earth exploration became the priority. This is compounded with the fact that the technical difficulties of reaching another planet are indefinitely greater than flying to the moon. Yet this has not stopped space enthusiasts from dreaming of a day when we will land on another planet, the most obvious choice being Mars. Mars is the second closest planet to Earth in our solar system, and the most earth-like, therefore it is thought to be the easiest stepping stone in our quest to become a multiplanetary species.
When the orbits of Earth and Mars are closest, the distance between the two planets is 34 million miles, 1000 times the distance between Earth and the Moon. To travel this distance, we will need an extremely powerful rocket, and massive amounts of fuel. This is where our first problem arises. The only model of rocket we have ever built that would have been capable of carrying us to Mars – the Saturn V no longer exists. This rocket was the tallest, heaviest and most powerful rocket that has been brought to operational status, and only 13 were built. They were used to bring us to the moon, and the last was launched in 1973. Today, no rockets exist that could provide us with a return journey to Mars. In order to do this, we would need reusable rockets (which have not yet been invented). The more fuel we use, the shorter our travel time will be. There is, of course, investment in other modes of transportation. A vasimr engine could reduce travel time to 5 months, while antimatter could reduce it to 45 days. However, it will be decades at least until some of these technologies will be on the market and ready to use.
Alternatively, SpaceX, a rocket company founded by Elon Musk is in the process of designing ‘Super Heavy’ (also known as BFR), a rocket system that is hoped to be fully reusable, designed to carry up to 100 people on interplanetary flights. This rocket, alongside the ‘starship’, one intended to reduce flight time to anywhere on earth to under an hour, are some of the world’s current greatest underway inventions. Considering that SpaceX has, in 10 years become a company worth $25 billion, and has in only a decade, managed to become the world’s biggest rocket launching company, with over 50 successful missions, it is amazing to think what it may be able to do in the next decade.
The distance to Mars gives rise to another issue- the lengthy amounts of time that astronauts will have to spend in space. Getting to Mars will take roughly 240 days. Surviving this long in space is a challenge for any astronaut and its dangers are varied. The first is its impact on mental health. Despite the fact that all astronauts are heavily psychologically tested, depression and attention deficit are conditions that astronauts are likely to have to face. This is mainly due to the massive amounts of time they will spend staring at a black void. A recent study observing a group of people in isolation as the base of a volcano has determined that to avoid mental health issues such as depression and anxiety, astronauts will have to be kept busy with physical activity and work for the majority of the day.
Astronauts will however also be faced with many physiological dangers. The gravity on Mars is 38% of Earth gravity, at 3.7m/s2, compared to ours at 9.8m/s2. Throughout the journey to Mars, the gravity inside the rocket will be in micro-g’s (microgravity). The long-term effects of weightlessness for a journey of 7 months are likely to include the atrophy of the heart and muscles, balance and eyesight disorders, as well as a reduction of aerobic capacity and a slowing down of the cardiovascular system. When on Mars, the human body will have to adapt to small amounts of gravity again. The return journey will be even harsher, as astronauts will not have experienced our full gravity for several years. It may be possible to counter this problem by slowly reducing gravity in the spacecraft and then increasing it again on the return journey, but the technology for this is still questionable. Other dangers include those of disease. Growing evidence shows that prolonged periods in space can have a detrimental effect on the human immune system making astronauts more vulnerable to disease. In addition to this, outside dangers such as cosmic and solar radiation could cause cancer, dementia and impaired vision. To prevent these, engineers are in the process of designing suits and shelter that will be able to withstand heavy radiation. However, the dangers of stray rays piecing them will always be there.
Now that we can understand some of the dangers and issues that astronauts and technicians will face to get us to Mars, how soon will it actually be?
Elon Musk believes that SpaceX will be able to bring the first people to Mars by 2022. That is in just 3 years. Its objectives for this mission will be to confirm water resources, identify hazards and to build the initial infrastructure that will be needed to live on Mars for a significant amount of time. They optimistically believe that a second mission with crew and cargo aboard, will land in 2024.
NASA on the other hand is slightly less optimistic. They plan to take advantage of the point in a 15-year cycle when we will need to least energy to make the journey, and get to Mars by 2033. President Trump himself has issued a mandate urging NASA to do this. However, for NASA to fulfil its aim it will require an estimate of over $500 billion. Currently NASA’s annual budget is $19.5 billion. It would take many years for NASA to accumulate the funding for such a mission. This has led rise to the debate between whether it will be national or even international organisations such as NASA that will be the first to land humans on Mars, or whether it will be privately owned companies such as SpaceX, Virgin Galactic and Blue Origin, who will achieve this feat. National organisations lack the funding a mission of this scale would require, and therefore it is private companies that are launching a new space race. This race is not greatly international. Many companies that aim for interplanetary travel are based in the US, and they do not compete for dominance in achieving a goal, but rather for customers. Their aims include commercialising space travel in orbit, making life on other planets possible, and visits to the moon.
Once we have reached Mars, there is one more challenge we must overcome – how to survive there. The basic requirements for human life on earth are food, water, and shelter. Living on Mars requires the same things, and one more - oxygen. The Martian atmosphere is 100 times thinner than ours, containing 96% carbon dioxide. This is not breathable. For humans to survive on Mars, we would need to produce our own oxygen, and we would not be able to step outside without a spacesuit. Carrying enough oxygen from Earth to Mars to support around 6 people for 4 years would be impossible. Luckily, Michael Hecht a scientist at MIT has developed an instrument called MOXIE, a specialised reverse fuel cell that converts CO2 into O2. This instrument has been selected by NASA to accompany Mars 2020 (a rover being sent to Mars next year to aid the Curiosity rover). It is believed that a system like MOXIE, may in the future be able to provide oxygen on a larger scale that could support a mission to Mars.
The next challenge astronauts living on Mars would face is temperature. The average temperature on Mars is -630C. At the height of summer at the equator, it might reach 210C, while at night lows can reach -730C. This would make it impossible for astronauts or even future colonists to go outside without a highly insulated suit (this is forgetting the problem of Mars’s extremely low pressure at 0.6% of Earth’s).
Getting water on Mars will be another issue. Water is an extremely heavy substance and it would therefore be impossible to bring it from earth to our destination. Although Mars may look barren, it is not. Only a few cm under Mars’s red surface lies a layer of permafrost. Rovers have discovered that the Martian soil contains up to 60% water, and in addition to this, large amounts of ice are concentrated at its north and south poles. However, melting this will not be necessary as in 1998, a dehumidifier was invented that would be able to draw all the water needed to live on Mars from its atmosphere.
With possible solutions for obtaining water and oxygen on Mars, other key challenges revolve around shelter and food. Although it may be possible to grow 20% of settlers’ food requirements hydroponically in greenhouses, 80% of food will have to be dried and brought over from earth. The issue of shelter is possibly easier to solve. Initially astronauts are expected to live in their landers, and inflatable pressurised buildings. Later, it is thought that they will be able to build bricks out of the Martian soil, or live in caves and lava tubes.
Surviving on Mars looks as if it may be achievable. But will living in restricted shelter, without being able to go outside and breath fresh air really satisfy us? Although we currently see going to Mars as scientific exploration, some believe and hope that we will one day be able to live there. While Mars is the most earth-like planet in our solar system, the differences between the two planets are significant. The variety of life, nature and beauty on earth simply does not exist there.  Scientists say that it may be possible to terraform Mars, that we could heat the dry ice on the poles to thicken its atmosphere, we could sublime ice with solar sails to flood the planet with water, and we could create a water cycle with rain and snow similar to that on Earth. Yet these theories are not proven. For now, we must focus on getting to Mars, living there will be a separate issue.

By Caroline Utermann

‘A mutation is a change in the DNA at a particular locus in an organism.’ Mutation plays an important role in evolution and is the ultimate source of all genetic variation. It is salient as the introductory step of evolution because it creates a new DNA sequence for a particular gene, creating a new allele. Gene mutations occur very rarely but its rate can be artificially increased by mutagenic agents such as mustard gas, x-rays and ultraviolet light to give induced mutations.
 
Genetic mutations can be classified in two major ways: hereditary and somatic. Hereditary mutations are present virtually in every cell in the body and are inherited from a parent. Due to their presence in the parent’s gametes, the mutations are also referred to as germline mutations. If a mutant gene is passed onto offspring, when growth occurs due to mitosis, the mutation will be present in all cells. The other type of mutations is somatic (acquired). These occur during a person’s life and are therefore present only in some cells. These can be caused by environmental factors such as ultraviolet radiation from the sun, or due to an error made during cell division, which is called non-disjunction. Somatic mutations cannot be passed to offspring due to the mutations not being present in gametes.
 
A number of regions of DNA possess dominance determining when and where genes are turned ‘on.’ Occurring mutations in these parts of the genome can substantially change the way the organism is built; a mutation in a control gene can cause a cascade of effects in the behaviour of genes under its control. An example of a control gene is hox genes. They are found in a number of animals like humans and designate where the head goes and which regions of the body grow appendages. Such genes assist in the directing of the body’s unit construction eg. segments, limbs, and eyes. Thus evolving an extensive change in basic body layout may not be so unlikely; it may simply require a change in a Hox gene and the favour of natural selection.
 
‘Mutations can be either beneficial, neutral, or harmful for the organism.’ Though it is said that factors in the environment an influence on the rate of mutation, they are not thought to influence the direction of mutation. This means that exposure to harmful chemicals may increase the mutation rate, but will not cause more mutations that make the organism resistant to those chemicals. In this respect, whether a certain mutation occurs or not is unallied to how serviceable that mutation would be, proving the concept that mutations are random. For example, in the U.S. where people have access to shampoos with chemicals that kill lice, a lot of lice that are resistant to those chemicals are commonly encountered. Two possible explanations can arise for this:

‘HYPOTHESIS A - Resistant strains of lice were always there — and are just more frequent now because all the non-resistant lice died.
HYPOTHESIS B - Exposure to lice shampoo actually caused mutations for resistance to the shampoo.

In 1952, Esther and Joshua Lederberg performed an experiment that aided in showing that mutations are random. They focused on the idea that bacteria grow into isolated colonies on plates. These colonies have the ability to reproduce from an original plate to a new plate by the process of ‘stamping’ (stamping the original plate with a cloth and then stamping empty plates with the same cloth). Bacteria from each colony are picked up on the cloth and then deposited on new plates. This led to Esther and Joshua hypothesising that antibiotic resistant strains of bacteria surviving an application of antibiotics had the resistance before their exposure to the antibiotics, not as a result of the exposure. Their experimental set up is summarised below:

This shows that before the encounter of penicillin the resistant bacteria were present in the population thus did not evolve resistance in response to the exposure of the antibiotic. Moreover, from the evidence available, we can hence deduce that mutations might therefore preferentially form around existing ones.
​

By Gaya Giritharan, 10F

CN: picture of brain surgery

​How do brain tumours form?
A brain tumour occurs when brain cells divide and grow in an abnormal and uncontrolled way. When a cell divides, it copies its genes and replicates itself. Sometimes however, mistakes occur in this process, and are known as mutations. Whilst some mutations are harmless, others cause the cell to divide uncontrollably.
 
The mutation causes the cells to behave as though they are receiving a growth signal or deactivates the checkpoints that would stop the cells from dividing. Therefore, the cells continue to divide uncontrollably, forming a tumour

​What is glioblastoma?
 
Glioblastomas are the most common and aggressive type of brain cancer that forms from cells called astrocytes in the nervous system. They belong to a group of brain tumours called gliomas, which are malignant tumours of the glial tissue. The average age of patients with glioblastoma is 64 years old; its risk increases with age. Whilst glioblastomas are mostly found in the cerebral hemispheres, they can be found anywhere in the brain.
Glioblastoma is a ‘diffuse’ tumour, meaning they are infiltrate and able to spread into healthy tissue in other parts of the brain, and therefore is very fast growing and fast spreading. This makes it very difficult to pinpoint precisely where the tumour starts and ends. Particularly aggressive glioblastoma are able to even spread to the opposite side of the brain through connection fibres, known as corpus callosum. Gliobastoma’s ‘diffuse’ property is particularly problematic when tumours spread near to important regions of the brain that are essential to functions such as movement and coordination.

​Symptoms and side effects of glioblastoma
Due to mass swelling from the fluid surrounding the glioblastoma (edema), patients develop symptoms very quickly. The most common symptoms are nausea, vomiting and severe headaches, and are predominantly due to the increased pressure in the brain as a result of the tumour and swelling. Neurological symptoms are also not uncommon, for example, weakness, sensory changes, difficulties with balance, and neurocognitive or memory issues.
 
Treatment of glioblastoma
Mark Gilbert, director of the Neuro-Oncology Branch in NCI’S Centre for Cancer Research said, “Glioblastoma is one of the hardest to treat in the history of oncology.” Despite continued efforts to develop promising treatments for glioblastoma, none have proved successful, with only 3.3% of patients living for longer than 2 years. The usual treatment for patients with glioblastoma is a surgery to remove most of the tumour, followed by chemotherapy and radiation.

​Surgery
Commonly, surgery would take place in an attempt to remove as much of the tumour as possible- a procedure known as debulking. It is difficult to remove the entire tumour because glioblastoma is a diffuse tumour, which means it can spread into the rest of the unaffected brain, and so it is difficult to tell the difference between affected and unaffected brain tissue.
There have been recent advances, which have improved the extent to which the tumours  can be removed in surgery. Prior to surgery, patients are given a drink containing the substance 5-ALA, which causes the affected cells to glow pink under violet light. This makes it less difficult to tell the affected and unaffected cells apart, and so more of the tumour can be removed.
Surgery is also used for palliative treatment in cases where the tumour cannot be removed- intracranial pressure is reduced to relieve symptoms.
 
Radiation
Radiation involves the use of high precision high-energy beams, for example X-rays, gamma rays or protons, to kill the affected cancer cells.  An immobilization mask is worn by the patient to hold their head in the same position and limit movement. Intensity-modulated radiation therapy is an advanced mode of radiotherapy that uses computer-controlled liner accelerators to deliver precise radiation doses to a malignant tumour. It allows for the radiation dose to conform more precisely to the 3D shape of the tumour by controlling the intensity of the beam in small volumes. The treatment is planned specific to the tumour using the CT and MRI images of the tumour in conjunction with computerized dose calculations to determine the dose intensity pattern that is best suited for the tumour.

​Chemotherapy
Chemotherapy is a technique that uses cytotoxic drugs to kill the affected cancer cells. Temozolomide, Iomustine and carmustine are the most commonly used drugs in chemotherapy. Temozolomide works by preventing the tumour cells from making new DNA, which prevents them from making new cells and therefore growing. It also makes the affected cells more sensitive to radiation, so chemotherapy and radiation treatments are often used together. Whilst radiation acts on the affected tumour cells, chemotherapy acts on all dividing cells, but healthy cells are able to repair themselves easier than the tumour cells, so few healthy cells die after treatment. The various ways in which chemotherapy can be given are:
 
Tablets- chemotherapy drugs can be taken in tablet form and are absorbed and carried around the body in the bloodstream to reach the affected tumour cells.
Injection/drip- chemotherapy drugs can be injected into a vein or into the spinal fluid. A drip may be used to insert the drug into the bloodstream, where it is absorbed and carried around the body to the affected cells.
Wafers- drugs can be put inside a polymer wafer and inserted into the brain during surgery. The wafers are made of a biodegradable material so they can dissolve over a few weeks, releasing the drug into the brain to kill the tumour cells.
 
Immunotherapy-Vaccinations
Whilst several immunotherapy-based treatments have proved unsuccessful in facing glioblastoma, vaccinations has been considered to be one of the more promising approaches.
A particular advance in the use of vaccines for glioblastoma was made by Dr Jason Adhikaree from the University of Nottingham, who proposes to use dendritic cells, a type of white blood cell, to create the vaccine. The dendritic cells would be taken from the patient’s body and ‘taught’ to recognise and kill the glioblastoma-affected cells. They will then be injected back into the patient’s body, in which they can attack the tumour cells.

By Maheria Rashid

Over half-term, we both attended the EDT's STEAM workshop. It was a very informative and fulfilling 3 day workshop held in London. They helped us learn about the different routes we could take into our future careers in STEAM. We went to Harrow College, University of Westminster and Costain Skanska. We learnt vital skills for the world of work like giving presentations and interviews. Overall, it was a great experience and we thoroughly recommend that you look into one of these courses in the future! 

By Hannah Tang and Sienna Parekh

Update from Mr Waddington: the EDT's website has a huge amount on offer for students interested in STEAM - http://www.etrust.org.uk/young-people