Team:Bordeaux/HP/3PS
Synthetic biology is part of your daily life and you might not even know it. It is present in
sectors such as the industry, health, energy or even agriculture. Synthetic biology appeared in the XXth century. It is one of the fields that studies life
sciences. It blends knowledge from fields such as biology, genetics, chemistry and engineering disciplines (mathematics models and computer simulations in particular). Amongst the key tools used in synthetic biology, need to be mentioned DNA sequencing and bio-computer sciences. The combination of these two techniques allow, for example,
to identity positions and functions of a gene of interest. Huge databases are available, namely the National Center for Biotechnology Information (NCBI) and Protein Data Bank (PDB), that compose an essential source of information when setting up a synthetic biology project. Synthetic biology has allowed many advancements. A first example is the modification of Saccharomyces cerevisiae (beer yeast) in order to increase the production of artemisinic acid, the precursor involved in the anti-malaria treatment (High-level semi-synthetic production of the potent antimalarial artemisinin, Nature, 2013). This permitted a reduction
by half of the costs and an increase in the treatment availability. A second example is the production of hydrocarbon. Genes in E.coli where modified and permitted the synthesis of a bio-fuel (Escherichia coli Genetic engineering of Escherichia coli for biofuel production, 2010). Its metabolism was then improved to produce these hydrocarbons in greater quantities.
The field of synthetic biology is currently expanding, especially in France, in the United States and in Japan. It gives high hopes for numerous industrial applications in the fields of health (more efficient therapies), energy (bio-fuels), materials, the environment (waste management) and agriculture (soil adapted crops). Full of promises, synthetic biology has proved itself, but still has a long way ahead of itself. Linejy & Maurene – iGEM Bordeaux From March 14th to 18th 2016, in Bordeaux, took place the week dedicated to the brain with numerous workshops, film projections, and conferences. In order to correctly honor the human brain, its incredible talent – memorization – must be mentioned. But what is memory? It is our brain's capacity to store information concerning past events, with the aim of recalling them later if necessary. This is why we feel at ease with known people or in a familiar environment. There are two types of memory. The first one, called immune memory, is associated with the immune system. When our body is attacked by a foreign entity, a virus for example, our immune system stores its characteristics and the actions that were taken to fight it off. In case of a re-infection by this same entity, our immune memory allows a more rapid and more efficient response. Biologically speaking, memory is the creation of a connection between two brain cells, called neurons. An electric signal is transmitted from the pre-synaptic neuron along the axon to the synaptic button, where a chemical molecule – a neurotransmitter – is released. These molecules such as acetylcholine cross the synaptic cleft between the two neurons, then bind to the receptors on the surface of the post-synaptic neuron. The chemical signal is then transformed into an electric signal again. Memory depends on multiple factors such as age, gender and genes. Indeed, memorization is easier before 30 years-old because our capacity to concentrate is better. Memory disorders can appear with age or be the consequence of pathologies such as a stroke or Alzheimer's disease. However, in many cases, cerebral plasticity allows a partial or total recovery of souvenirs. It is even possible to improve one's memory. “Intelligent” drugs increase blood surges to the brain and release chemical substances there, improving concentration. But playing memory games, using keys words, or eating foods enriched in unsaturated omega-3 such as tuna or oysters, can be equally effective. Memory is therefore a very complex process that uses billions of neurons. In our daily lives, it is constantly sought out for by our body and our need to recall previously stored information. The proverb “Even if you lost your head, you've still got your feet to do the work” proves our memory must be nurtured. Thus, remember to exercise your brain and memory from time to time in order to be at your best! Maurene – iGEM Bordeaux Sleep is a natural resting state during which the body is not active and the mind is unconscious [1]. When in a state of sleep, typical signs include closed eyes, a change in breathing pattern, a peaceful facial expression, diminished responsiveness to environment, and decrease in body temperature. Until the 1950s, sleep was thought of as a passive activity during which the organism was on “standby”. But we now know sleep is a dynamic activity during which the brain is far more active than during any other period of a 24-hour day. Sleep is necessary and affects our daily functioning and our physical/ mental health in ways searchers are still trying to understand. When sleep deprived, the body sends signals such as yawning, scratchy eyes, difficulties to concentrate, and muscular fatigue to motivate sleep. Our environment is the main reason to the induction of sleep. A notable example is nightfall. During the day, the pineal gland located just above the middle of the brain is inactive. But as night falls, our eyes detect the reduction of sunlight. This information is transmitted to the Central Nervous System who stimulates the pineal gland. It starts producing melatonin, a natural hormone, released into the blood. As melatonin levels rise, you feel less alert and sleep becomes more inviting. Melatonin levels in the blood stay high for about 12 hours [2]. Sleep is a cycle composed of five phases: stages 1, 2, 3, 4 and REM (Rapid Eye Movement) sleep. These five phases have different lengths: 50% of total sleep time is spent in stage 2, 20% in REM sleep, and 30% for the three other stages. But this distribution changes over time (e.g. infants spend 50% of total sleep time in REM sleep) and can vary from one individual to the next. Stages 1 and 2 are considered light sleep periods, whereas stages 3 and 4 are deep sleep periods. During stage 1, we drift in and out of sleep and can easily be awakened. Eye movements are slow. Muscle activity decreases but is still present which is why many experience sudden muscle contractions called hypnic myoclonia, often preceded by a sensation of starting to fall. The mind is still conscious allowing fragmented memory of images if awakened. During stage 2, eye movements stop and brain activity (measurable with electrodes) becomes slower, with occasional bursts of rapid waves reflecting sparks of brain activity. During stage 3, delta waves are on the majority reflecting extremely slow brain activity. Smaller and faster brain waves are interspersed. In stage 4, the brain almost exclusively produces delta waves. In stages 3 and 4, there are no eye movements and no muscle activity. It is very difficult to wake someone during these two stages, but if awakened, dizziness, grogginess and/or disorientation can be experienced. Furthermore, night terrors, sleep walking and bed-wetting occur during these two stages. The amount of sleep each person needs depends on many factors, including age. Toddlers generally require 16 hours a day while teenagers need about 9 hours on average. During adulthood, 7 to 8 hours a night seems sufficient, but some people require only 5 hours, whereas others need 10 hours each day. Women in the first 3 months of pregnancy often need several more hours of sleep than usual. Sleep deprivation was previously used as a technique to “break” someone during a long-term interrogation process. The British government in the 1970s used it to obtain information from trained spies. The Central Intelligence Agency in the United States used it to interrogate Abu Zubaydah described as a terrorist logistics specialist in the 2000s. Although it is not considered a method of torture, sleep deprivation was mentioned as “a practice of inhuman and degrading treatment" in the European Convention on Human Rights [5]. Answer of an american survey of Behavioral Risk Factor Surveillance System (BRFSS)" A study also shows sleep disorder is closely related to occupational stress [4]. Nurses in the department of gynecology and obstetrics, emergency department, and ICU show higher risks of sleep disorders due to factors such as many times of night shift per month, no frequent exercise, many efforts and few rewards. Some people suffer from lack of sleep. However intentional this is, sleep insufficiency is becoming a public health problem. It is increasingly recognized as linked to motor vehicle crashes, industrial disasters, and medical and other occupational errors. Other some people suffer from sleep disorders, obstructive sleep apnea or insomnia on a biological level. In 2008, an estimated 50-70 million US adults suffered from sleep and/or wakefulness disorders. This can also result in an increased risk of developing chronic diseases such as hypertension, diabetes, depression, obesity, and cancer. These people have an increased mortality and a reduced quality of life and productivity [6]. To conclude, sleep is necessary in order to maintain a good balance and healthy lifestyle. It is a complex mechanism with essential functions, the scientific community still doesn't fully understand. The symptoms of sleep deprivation are various and disastrous. This is why new treatments must be found to heal the increasing number of patients suffering from sleep disorder. Now, sleep tight and don't let the bed bugs bite! Maurene – iGEM BordeauxWhat is the synthetic biology?
But what is synthetic biology?
Synthetic biology ensures the creation of reliable biological systems with complex functions.
These approaches are used in research to solve mysteries that surround certain mechanisms, but also in the industry where organisms are genetically modified in order to provide a molecule of interest. For example, antibodies used in the vaccine Lymphoma© are produced in large-scale quantities in the tobacco plant.
Two major approaches exist :
Chaperonins are proteins that are found in a cell and that ensure the correct folding of other proteins, an essential step for a smooth functioning of these proteins in the cell.What are the tools used in synthetic biology?
What is the use of synthetic biology?
In conclusion
The most recent advancement of synthetic biology goes back to March 25 th 2016. An article published in Sciences caused an uproar in the world of synthetic biology. Indeed, a team in the United States built a bacteria cell with only the minimum genes necessary for sustaining the cell in a live state. This study is a huge step forward in the understanding of the functions of numerous genes.How does memory work?
The second one, called cerebral memory, can be split in three major categories:
In conlusion
How does sleep work?
What is sleep ?
What causes a state of sleep?
Many other chemical molecules are emitted following environmental information detection by sensory organs. These molecules act on cells in the brain called neurons. The neurotransmittors emitted by these stimulated neurons control whether we are awake or asleep. Neurons in the brain stem which connects the brain to the spinal cord differ from neurons at the base of the brain: the first type of neurons produce serotonin and/or norepinephrine that keep us awake whereas the other ones have the capacity to switch off signals that keep us awake and cause us to fall asleep [3].
What are the stages of sleep? What functions do sleep stages have? [3]
The passage to REM sleep is characterized by: more rapid, irregular and shallow breathing; eye jerking in various directions; muscle paralysis; heart rate increase; blood pressure increase; penile erections. Dreams occur during REM sleep which one can remember if awakened during this stage. How much sleep do we need? [3]
The amount of sleep a person needs also depends on their sleep quota the past days. If they have been deprived, this creates a “sleep debt” requiring more sleep the following days. One doesn't adapt to getting less sleep than needed. You can only get used to a sleep-depriving schedule, but reaction times, judgment, health state, and mood are still affected by this. What symptoms are caused from a lack of sleep?
Problems caused by lack of sleep are of different degrees, going from minor to severe to deadly. Minor issues are frequent and non permanent. Catching up on sleep will put things back to normal. Examples include: aesthetic issues (sagging tissues under eyes, pulled traits, swollen eyelids), body symptoms (yawning, muscular aches and/or fatigue), mental symptoms (concentration difficulties, fatigue, sudden mood changes, annoyance). However, if sleep deprivation is continued, more severe problems appear such as memorization, severe weight gain/loss, fainting, depression, performance and reactivity decrease (driving, speaking, handling objects), madness, and seizure. Sleep deprivation leads to death in the worst cases. 
What health diseases are linked to sleep?
Few treatments exist for sleep disorders. Anti-snoring sprays for apnea and sleeping pills for insomnia are available in pharmacies, but these treatments are chemical. Furthermore, one can get used to them and no longer feel their effects. The iGEM Bordeaux 2016 aims to produce an alternative solution to these drugs. In conclusion
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