Micro Slavery


bacteria culture

This is the only way these modified organisms can live: in a dish in the lab

Bacteria can be both useful and lethal. In either case, scientists want total control over them to maximise their efficiency or prevent any diseases. However, it does sounds impossible: how can humans control a bacterium, which is a free living organism so small we can’t see it with our naked eye and is incapable of understanding our commands? But of course they have accomplished this, or otherwise I wouldn’t be writing an article on it.

Subjugating bacteria is done by a simple method. All living organisms require proteins made out of amino acids to live, and bacteria are no different. They use them to carry out many varied functions: they act as enzymes, hormones, connective tissue… so if you control how bacteria make proteins, you can basically dictate how they live their lives. Since proteins are coded by the DNA, scientists tweaked the genetic information so that bacteria didn’t code for proteins they way they would usually do. But changing the whole genome is a long, tiresome process; so instead, they targeted a specific set of genes which code for a specific set of proteins: those that are crucial for a bacterium to make other proteins. It is quite effective. If bacteria can’t make the proteins that guide DNA transcription and translation (the processes that produce proteins), then the bacteria are hindered and can’t work any further.

The modifications involved changing the bases in the DNA sequence so they didn’t code for the usual, natural amino acids. Instead, some new bases introduced coded for an artificial amino acid, created and only found in the lab, so proteins could only be made if this one artificial amino acid was present. This idea, although creative, was developed by two independent teams, one of which used a large, artificial amino acid and the other used three different artificial amino acids. Either way, if these bacteria wanted to survive, they would have to stay in the lab, the only place where they can obtain the amino acid necessary for creating proteins.

The main implications of this development are related to genetically modified organisms (GMOs). People fear that creating beings with features enhanced in the laboratory is dangerous, and if they somehow make it into the wild and grow there, they can harm other, more natural species, or reproduce with them, which would destroy the natural balance of natural selection. This technique solves both of those problems, since the new GMOs developed with dependency on this amino acid would only be able to live in the lab, and could be easily controlled and kept in small numbers.

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Antibiotic Hero


Antibiotics are the real wonder drug. They were a revolution in the 20th century, capable of fighting the most powerful bacterial infections. Scientists understood their potential and worked tirelessly to create a wide variety of them to harness their power, but eventually they stopped. Since the 1980s, no new antibiotic has been discovered. Since we have a great amount of them, it wouldn’t be too big of an issue, if it weren’t for a growing problem: resistance.

Due to the threat antibiotics represent to bacteria, these organisms feel a high selection pressure to evolve and develop new ways to defend themselves from these drugs. And they have succeeded. Many strains of bacteria, especially for diseases like MRSA and TB, have become immune to many antibiotics and are proving really hard to fight. Due to the increase in antibiotic resistance, there has been a hunt for new antibiotics in the recent years, and it has finally paid off.

The most common way to obtain an antibiotic is from bacteria themselves. We are not the only ones who want to get rid of them; competing bacteria do too. So when these bacteria develop chemicals to destroy other bacteria, we need to extract them and use them to our advantage. But to extract the chemicals, bacteria need to be cultured in the lab, which can be difficult at time, since the most used bacteria for this process are found in the soil, which has conditions difficult to recreate in the lab. A new method created by researchers in Boston could solve this: it consists of creating a culture with three layers: two layers of soil on either side of a semi permeable membrane. These are perfect conditions for bacteria and have made it possible for thousands of them to grow and for a possible new antibiotic to be isolated.

teixobactin

Teixobactin could fight TB and other diseases which, over the years, have become immune to our medications

 It’s called teixobactin, and it targets proteins on the membrane of bacteria, eventually killing them. Because of its complicated mechanism, it is very hard for bacteria to develop resistance to its action. However, it is not impossible. Scientists predict that if used correctly (that is, without overprescribing), teixobactin could be effective for over 30 years, quite a long lifespan for an antibiotic. As it is completely new and bacteria have never been exposed to it, many say it could be the key to fight multidrug resistant bacteria, fighting superbugs and giving us and edge over the most fierce and dangerous infections. These hopeful results have yet to be confirmed in human trials, but the effectiveness of the new antibiotic seems to be as good as it sounds in animal tests.

 With this new method and this new antibiotic, the future of medicine could prosper, and bacterial infection could remain an enemy we can defeat.

2014 Science Highlights: Part 1


Another year passes, so it’s time for another round up of the most interesting scientific events that have happened in the last 12 months. 2014 has been a year full of fascinating discoveries, both in this planet and outside of it, but with some disappointing realisations too.

 1. The Ebola Crisis Continues

ebola

The Ebola virus keeps taking lives and will continue to do so until we find a treatment

The Ebola virus gained a lot of attention this autumn when it grew to an unprecedented size: it became the larges Ebola outbreak in history. In fact, the WHO declared it a global public health emergency and many countries and organisations rushed to contribute some help. At first contained in West Africa, there were a couple of isolated cases in Europe and the USA which caused even more panic, but it has died down. As with many catastrophes, after the initial spotlight, the Ebola pandemic has lost a lot of attention from the public, even though it has not stopped growing. However, it is slightly more controlled, and due to all the press it received, plenty of research is going into treating it, which should hopefully yield some treatments or a vaccine.

2. Stem Cells Stump

Mouse embryo with beating heart

The original STAP cells, which held so much potential, but turned out to be too good to be true

There was a great flurry of excitement at the beginning of this year when researchers in Japan claimed to have created stem cells by simply dipping blood cells into acid. The STAP (Stimulus-Triggered Acquisition of Pluripotency) cells were great for medical research since they got rid of the ethical issues of using embryonic stem cells. The potential of this easy and cheap method were immense, so as soon as the results were published, many scientists from around the world tried to carry out the experiment themselves. But they couldn’t. The results couldn’t be replicated. A more in depth investigation showed that the results of the original experiment were not accurate, and now the theory has, unfortunately, been disproved.

3. Rosetta and Philae

rosetta philae

A representation showing Rosetta (left) and Philae (right) on the surface of 67P

You can’t summarise 2014 without mentioning either the Rosetta spacecraft or the Philae lander. They have both accomplished feats in science which could have only been dreamed of. Rosetta has been in space for 10 years in pursuit of the 67PN comet which is travelling through our Solar System. This year it finally reached it and is now moving relative to it, becoming the first object to rendezvous with a comet. But Rosetta is not the only one who’s kept busy. After rendezvousing with the comet, Rosetta released Philae, a small robot whose objective was to land on 67P. And so it did, although it was a bumpy ride. Unfortunately, it ran out of battery soon after the landing, making it impossible for it to analyse the comet and take samples; its original purpose. But 67P is supposed to pass close to the Sun at some point, which might reactivate Philae and help it complete its mission

4. Dusty Waves

primordial waves

The graph showing what scientists thought were primordial waves, the proof of inflation theory, but is actualy dust

There was another fascinating discovery this year, in which a special type of wave was detected coming from space, with massive implications. Called primordial waves, they are theorised to have been produced during the Big Bang, and if their existence was confirmed, the theory of inflation, which states that the universes started expanding just after it was created would be proved. What were supposed to be these waves were then detected, and scientists were ecstatic. The Big Bang is one of the most confusing aspects of science, and this discovery could help clarify it greatly. But again, after further investigation, the results did not look too good. The alleged ‘primordial waves’ were most likely just dust in the Universe, interfering with the results and creating false hopes.

5. Young Calls Young

blood

Blood could hold secrets for eternal youth

In a truly zombie-like procedure, scientists sewed young and old rats together so they created blood vessels between each other and shared blood. After some time, they investigated how tissues had grown and developed in the two rats and the results were utterly fascinating. The old rats had created more neural connections in their brains, their muscles had healed faster, and their heart muscles had been rejuvenated. However, the young mice suffered the opposite effects.

But scientists concentrated on the positive side, on what chemicals in the young rats caused these changes in the old ones and detected a specific protein, GDF11, which seemed to activate stem cells and cause all these beneficial effects. They also discovered chemicals in older mice which did the opposite: they made stem cells react slower, which in turn deteriorated the health of the younger rats. The next step is finding the equivalent proteins in humans, so that older people can be healed from diseases such as Alzheimer’s or arthritis.

 

Stay tuned for the more of the most interesting scientific events of 2014 in the epic conclusion: 2014 Science Highlights: Part 2.

A Bacterial Lunch


The secrets to weight loss may not lie on strange synthetic chemicals or unhealthy new fad diets, but actually in some simple bacteria we’ve known for as long as we’ve been born.

The bacteria in our intestines help us digest the food we intake; from carbohydrates to proteins to fats. But there’s something we humans can’t actually digest: fibre, so instead we use it to push the rest of the food through our guts and prevent constipation. However, since we should eat plenty of fibre, some bacteria use the excess and digest it too, and when doing so, release a substance scientists call propionate. This chemical triggers a reaction in our cells which results in them releasing a specific type of hormones: satiety hormones, such as PYY and GLP-1. As their name suggest, they are used by the body to make people feel ‘full’, by sending messages to the brain telling it to stop eating. In people, it usually takes a decent amount of fibre to trigger this response, so the person has to ingest a large amount of food before this reaction happens.

bacteria lunch

Don’t they look delicious?

But in developed countries, there is an excess of food, so people over indulge and end up over weight or obese. To stop this, scientists have been working with these bacteria in our guts and have come up with a possible solution.

In the form of IPE (inulin-propionate ester), propionate is in a concentration 8 times as large as that of a normal dinner, high enough to trigger the “I’m full” response despite not eating enough fibre. In theory, if a person takes this at some point during the day, they will produce the satiety hormones that will tell the body they are full so the person won’t feel the impulse to eat. The objective of the drug is therefore to reduce weight gain by reducing food intake.

To test this drug, some interesting experiments were carried out. The most curious one consisted of having two groups of people: one taking IPE and one not (the control) face a buffet and an open invitation to eat as much as they wanted (a.k.a. heaven). People with IPE in their system ate 14% less than those without IPE. And if the drug was given to people leading normal lives for six months, those taking the drug ate on average 9% less than those with no drug.

So although eating bacteria’s remains doesn’t sound like the most appealing plate in the book, it could produce long-term improvements in our health.

Smoking Out Y


When people smoke, not only do they inhale burnt pieces of paper which damage their lungs, or have tar accumulate inside of them, which is likely to cause lung cancer, or inject nicotine into their bloodstream, which increases heart rate and blood pressure; it also causes the Y chromosome to eventually disappear. Of course, this only affects males, since the presence of a Y chromosome determines you’re male in gender, but for women smoking is still unhealthy and should be stopped.

Chemicals in tobacco affect this chromosome during cell division or mitosis when the chromosomes are being separated to either sides of the cell. Damage to the chromosome can build up until it eventually disappears. The study, carried out in Sweden, showed that people (men, specifically) who smoked had 33% more chances of loosing their Y chromosome compared to men who didn’t smoke.

However, it has been widely thought for many years that the Y chromosome is so small (in fact, it’s the smallest out of our 46 chromosomes), that its loss wouldn’t have too dire consequences. Past experiments on cells show that they can survive just as well without said chromosome. But new studies show that the lack of this chromosome, although not directly fatal, can shorten life duration and causes an increase in the likelihood of developing cancer. Lung cancer or any other cancer having to do with the respiratory system aside, male smokers are twice as likely to develop cancer as female smokers.

A possible explanation for this is that the Y chromosome contains tumour suppressing genes, so if it disappears, tumours are not going to be controlled and inhibited and therefore will be able to reproduce uncontrollably, causing cancer.

The newest research shows that this effect changes intensity depending on the dose of tobacco smoked. Obviously, the more tobacco you smoke, the more likely you are to suffer from its negative effects. But there’s a silver lining: this process is reversible. If you were to stop smoking, your cells would stop taking damage and after some time they’d be repaired, so you would have the same percentage of healthy cells with a Y chromosome as a non-smoker.

y chromosome

The Y chromosome is more important than you think in the fight against cancer

 

Genesexual


gene

Although genes could now have a very important effect on men’s sexuality, the environmental impact is still significant

In the largest study on the matter up to date, scientists from Illinois have investigated the DNA of hundreds homosexual men and have found revolutionising results that show that being gay could have a strong genetic influence.

Although the genome is a vast structure, home to thousands of genes, there were two very specific areas contained in it that were analysed in detail. Both these areas have been known by the scientific community for quite some years. For example, one of them, located in the X chromosome, and called Xq28, was first suspected to be related to homosexuality in a smaller study in 1993; whereas the other one, 8q12 in chromosome 8, was discovered in 2005. The aim of this experiment was to confirm these areas had some effect on sexuality in men and investigate how they caused this effect.

Overall, 818 men, all gay, volunteered for this project. This is almost 20 times more people than in the study in 1993. But to make it reliable as well as statistically accurate, many of the test subjects were brothers; in some cases, even non-identical twins! Having two closely related individuals with similar genetic makeup can make differences in their genome stand out and their distinct effect on the phenotype much easier to find. Using DNA collected over many years from blood samples, the scientific team looked closely at these men’s gene sequence. They were looking for small differences in the coding between brothers, specifically for single nucleotide polymorphisms, which are changes of only one base or nucleotide in a gene. After all the DNA samples were analysed, 5 single changes in the nucleotides were observed, and most occurred in these two regions of the genome.

What makes this study’s results worth considering is the fact that the only feature all these men shared was their sexuality: they were all gay. They varied in every other physical feature; so any change in those areas of their genome that was common to all men had to be related to their sexual orientation.

But both Xq28 and 8q12 are filled with genes, so although we know almost certainly that there are genes in there related to homosexuality, there is still not a distinct list of genes that could cause someone to be gay. Finding them hidden in these large areas full of coding is the team’s next task.

This discovery has, as could be expected, grave implications. It could help resolve all discrimination against gay people, and show that their sexual orientation is not a choice, but actually who they are. But unfortunately, it could lead some people to consider homosexuality as a biological mistake or a negative mutation, and even resort to genetic engineering to identify and remove ‘gay genes’ from embryos. This is wrong on many levels, but the most related to this article is that a person’s sexuality is not only defined by their genes, but is also affected by the environment they live in, so changing their genes is unnecessary and would not prevent homosexual people from being born.

Chocolate Memories


Everyone loves a good cup of hot chocolate, except those weirdos who don’t, but now it seems this tasty treat could actually have tremendous benefits other than its deliciousness.

hotchocolate

What’s not to like?

Memory deficit usually comes hand in hand with old age. To shed some light onto this problem, scientists at Columbia University carried out an experiment on volunteers aged 50 to 69. These people were divided into two groups; one was given normal hot cocoa, whilst the other was given the same beverage but with increased amounts of flavanol. Flavanol is a chemical commonly found in chocolate, but which also appears in vegetables, fruits and even tea.

Before the investigation started, the patients had an MRI scan taken, and went through a memory test. In it, the volunteers were shown a group of about 40 shapes, and after a minute, they were shown a larger group of shapes, in which they had to recognize the previous ones. During the three months the study lasted, they were given two cups of the drink every day. After this period of time, MRI scans were taken again and the subjects repeated the test.

The results were astonishing. After being given this high-flavonol diet, the patients of the study had improved their memory by a highly considerable amount. It had even become similar to that of a person 30 years younger, as shown by the memory test. The MRI scans also revealed some striking information. There was an increased blood flow in the dentate gyrus of the patients, an area of the brain in the hippocampus, by almost 20%, which had been previously related to memory problems in elderly people.

But if you’re between 50 and 69 years old, don’t start stuffing yourself with chocolate. The flavonol content of those drinks which enhanced memory was of 900mg, which is 90 times as much flavonol as a normal chocolate bar. However, it is still an interesting discovery, which most scientists agree should be investigated further, in greater trials, and with more variables considered.

Paralysis Cured By A Nose


Paralysis is a terrible condition suffered by over 3 million people, but can actually affect anyone and has very few solutions. In an almost miraculous turn of events, this has now changed thanks to scientists, doctors, and curiously enough, a chef.

David Nicholls is a world-known, Michelin Starred-chef whose son Daniel became paralysed in an accident in 2003. Since then, he has tried everything possible to help his son, including creating the Nicholls Spinal Injury Foundation (NSIF) which aims to raise awareness of paralysis and fund any promising cure projects.

Spinal surgery breakthrough

Darek Fidyka, showing the extent of his recovery

One of these donations was used by a team of researchers at UCL to pioneer a mechanism for nerve regeneration in spines. They were lead by Professor Geoffrey Raisman, a scientist with a long history in nerve cell innovations. He was the discoverer of ‘plasticity’, a quality our bodies possess by which damaged nerve cells can regenerate. Although this idea was controversial at first, it eventually opened the door for possible repair treatments.

His newest brilliance involves implanting cells from the nose to the damaged area in the spinal cord. But this doesn’t work with any nose cells. It specifically requires OECs, which stands for olfactory ensheathing cells, and their role is to repair broken nerve cells in the nose so that communication between these and the brain is restored, and our sense of smell works correctly.

This idea was applied by a group of doctors in Poland, lead by spinal repair expert Dr Pawel Tobakow, with surprising results. The patient they treated was Darek Fidyka, a man who was stabbed in the back so his spinal cord was cut in two, leaving a gap with severed nerve cells. The operation consisted of implanting Fidyka’s OECs into the gap where these, instead of healing nose nerve cells, would bridge the separated spinal nerve cells so given time and the appropriate rehabilitation, the spine would no longer be divided into two.

And so it happened. Two years later, the nerve cells on either side of the cut have regenerated and the connection between these has been re-established, effectively ‘curing’ the paralysis. The changes to Fidyka’s life have been enormous. Weeks ago, he wasn’t even able to feel his legs. Now, not only is he regaining some feeling, but can also walk and is even capable of driving a car! More patients are waiting to be treated with this method in hopes of recovering from this horrendous condition and to prove this treatment effective enough so even more injured people can be cured and the fullness of their lives restored.

Nobel Prizes 2014: Part 1


Probably the most prestigious scientific award, the Nobel Prize is, for many, the intellectual event of the year, where the world’s greatest scientists are rewarded for their hard work and brilliance. As of yet, only two results have been announced, those for physics and physiology, and the rest will be unveiled as the week progresses.

The 2014 Nobel Prize for Physiology or Medicine went to… John O’Keefe, May-Britt Moser and Edvard Moser for discovering the ‘GPS’ system in brains.  

human gps

Not a literal GPS in our head, but a group of cells that enable us to travel

It all started 40 years ago, when O’Keefe was investigating rats’ brains and their response to certain stimuli to understand their behaviour. In one experiment, he found that in a group of nerve cells in the brain, some became active when the rat physically moved to one area of the room, whilst other cells became active in other areas of the room. The conclusion he reached was that this group of cells was making a mental map of the rat’s environment to help it locate itself and move around. The ‘place cells’, as he called them, were a revolution in the field, but it took O’Keene 40 years and two collaborators to win the famous Prize.

The other recipients of the award are the Mosers, a married couple who, working in O’Keene’s lab, examined in more depth the mechanism and using modern technology, discovered that a close group of cells in the entorhinal cortex also helped in movement. What they found was that these new cells could be active in many positions of the room, not just one specific location. ‘Grid cells’ is their name and they do exactly what their name would suggest: they create a grid of their surroundings.

Both the place cells and the grid cells are used in human brains too, and their work is essential for us to be able to travel, even from one room to another, without getting lost.

The Nobel Prize for Physics went to… Shuji Nakamura, Isamu Akasaki and Hiroshi Amano for the invention of blue LEDs.

At first sight, it looks like they gave these men a Nobel Prize for inventing a bulb, but it is much more complex than that. First of all, let’s explain what an LED is and how it works. An LED stands for Light-Emitting Diode and it is used to produce light. It works by having thin sheets of material over each other, some of which contain a lot of electrons whereas other don’t and so have positive ‘holes’. When an electron collides with this hole, it emits a photon; a particle of light.

blue led

Making blue light is much harder than it may seem!

Red and green LEDs have been around for a long time, but only blue light could be transform into white light. The problem is that blue light has a higher energy and therefore very few materials can emit this wavelength. So when Akasaki, Amano and Nakamura discovered gallium nitride, it was a real miracle. This material is special because apart from having electron-rich areas, it can also produce a layer of itself which lacks electrons, so that together, they can react and produce blue light.

This apparently simple mechanism has had unimaginable consequences, which is the main reason why the Royal Swedish Academy of Sciences has decided to award them the prize. Blue LEDs gave us the opportunity to make white light by coating the bulb with a substance called phosphor. Thanks to this combination, we now use blue LEDs everywhere, from our TV screens to the lightning in the streets. The advantage it has over the normal, incandescent bulbs is that it can last 100 times longer, and is extremely more efficient. In fact, it is said that if all light bulbs were switched to these energy saving ones we could half the electricity usage by lightning in the whole world.

MagnetoMemory


We are constantly making new memories, at the same rate as we live them. But most of these will be lost, since they contain information we don’t really care about, like a boring bus trip or walking down the street. But some memories are more important and so remain in our mind, like those of family and friends, and it is a really heartbreaking when due to illnesses like Alzheimer’s disease they disappear.

hippocampus

The hippocampus controls memory formation

This new invention is therefore something to hope for. Scientists from Northwestern Univeristy, Chicago, discovered that when they applied a magnetic field on a patient’s brain their memory performance would be boosted. This was investigated in a trial, where two sets of patients were given either this treatment, called TMS for Transcranial Magnetic Stimulation, or a placebo. After, they were provided with images of people’s faces, and when a picture was shown, some words were read aloud. Once this was done, the patients were given a couple of minutes, and then tested to see if they could relate the images to the words they had heard. Those that had been given TMS scored better in the test than those without it.

But how does TMS actually work? Well, it has been known for quite a while that the nervous system works by a series of impulses of electricity. The brain is no different, so if you want to stimulate the brain, you want to apply an electric current to it. This can be done with drugs or surgery, but what makes TMS special is that it is non-invasive, so it doesn’t enter the patient’s body, making the whole procedure easier and somewhat safer. The magnetic field that flows through the brain creates an electric field, which stimulates the brain. If this is done in the right area, it can enhance certain abilities.

To improve memory, the immediate assumption would be to treat the hippocampus with TMS, since this is the area were most of the brain’s work on memory happens. But the hippocampus is too deep in our brains, so the magnetic radiation wouldn’t reach it well enough. Therefore, the researchers decided to work on a more superficial part of the brain that indirectly stimulates the hippocampus. The new electric current flowing through the brain caused memories to last longer, specifically the associative memories (those that link something to something else). However, the effects seemed to last for 24 hours only.

Still, with enough research, TMS could develop into an efficient treatment for memory-loss diseases, but care has to be taken since the brain is very delicate and even the slightest of changes can cause a chain reaction.