Vampire or Victim?

Brasov in Transylvania, Romania

Following my recent trip to Transylvania in Romania for work experience, I have decided to dedicate this post to the monsters and myths which stem from the region: specifically vampires. Like many historical ideas and beliefs, the creation of such a supernatural being likely served as an attempt to explain ailments that couldn’t otherwise be explained, before the emergence of scientific understanding. In this post, I will describe the medical condition most popularly believed to have led to belief in vampires.

The most commonly referenced illness used to explain away vampirism is porphyria, a group of inherited metabolic disorders in which haem (used in haemoglobin) production is disrupted. The production of haem from a chemical called ALA involves several steps, and each step requires the use of an enzyme. In people suffering from porphyria, one of those enzymes is faulty due to the inheritance of a mutated gene which codes for the synthesis of that enzyme. This means that the production of haem is slowed or even stopped, and as a result the ‘transitional chemicals’ made in the stages between ALA and haem, known as porphyrins, can build up to harmful levels. As well as this, the limited haem production can mean that not enough healthy red blood cells can be made. There are different types of porphyria depending on which enzyme is dysfunctional, most of which produce different symptoms with some overlap.

The most common form, and the one best related to vampires, is porphyria cutanea tarda (PCT) which affects the skin. PCT causes photosensitivity in which exposure to sunlight can cause painful, blistering and itchy skin… sound like something you’ve heard of before? A well known characteristic of vampires is that they burn in sunlight, hence must stay out of the sun and so have a dramatically pale complexion. Similarly many porphyria sufferers are indeed pale as, naturally, they avoid the sunlight due to their photosensitivity.  What’s more, healing after this reaction to sunlight is often slow and, with repeated damage, can cause the skin to tighten and shrink back. If this shrinking causes gums to recede, you can imagine that the canines may start to resemble fangs.

Another general symptom of porphyria is that when the accumulated porphyrins are excreted, the resultant faeces may turn a purple-red colour. Whilst the same conclusion may not be reached in modern times, historically this may have given the impression that the sufferer had been drinking blood which is another vampire hallmark. Interestingly, drinking blood could- and I say this tentatively- actually relieve some symptoms of porphyria. Whilst the haemoglobin would be broken down, the haem pigment itself could survive digestion and be absorbed from the small intestine meaning in theory that drinking blood would do the same for relieving symptoms as a blood transfusion would. Finally, garlic. Seemingly the most random trait of vampires is their aversion to garlic however even this could be explained by porphyria. Garlic can stimulate red blood cell and haem production which, for a person with porphyria, could worsen their symptoms as more porphyrins build up. This could lead to an acute attack in which abdominal pain, vomiting and seizures may occur. Seems like an extreme reaction, but perhaps…

So does porphyria explain how the legends of vampires came about? I would say so, but some folklorists and experts would disagree. It is suggested by such people that porphyria doesn’t accurately explain the original characteristics of vampires but more the fictional adaptations that have more recently been referred to. Folkloric vampires weren’t believed to have issues with sunlight at all and were described as looking healthy, ‘as they were in life’, which contradicts the pale complexion and blistering skin seen in PCT. Furthermore, it is still unclear whether or not drinking blood would truly relieve symptoms of porphyria and even so, how those affected would know to try it with no understanding of their disease and no craving for blood makes it all seem rather unlikely. Speaking of probability, reports of vampires were rampant in the 18th century yet porphyria is a relatively rare  occurrence and its severity ranges from full-on vampire to no symptoms developing at all, making it seem even less probable that such an apparently widespread phenomenon could be the result of PCT.

Whether you believe that porphyria caused the vampire myths or not, it certainly is an interesting disease that sadly has no cure (so far), is difficult to diagnose and relies generally on management rather than treatment. Here’s hoping that future developments using gene therapy and even research spun off of use of ‘vampire plant’ models could lead to improvements some day.

 

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Peanut or Pea-not?

The humble peanut is much loved around the world, making up 67% of all nut consumption in the US and can be found as an ingredient in a ridiculous number of foods or eaten as a savoury snack. Unfortunately, peanut allergy is also one of the most common food allergies with about 1 in 100 people in the UK being allergic.

My interest in this topic arose when someone broke the news to me that the peanut is not actually a nut. Okay, so maybe not the most ground-shaking piece of information but a surprise to me all the same. Turns out, the peanut is actually a legume. This is because a nut is considered to be a fruit whose ovary wall become very hard at maturity, hence the phrase “tough nut to crack”. Also, nuts tend to grow on trees. In contrast, peanut pods split open when ripe and they grow underground. In fact, they are scientifically classified as Arachis hypogaea with hypogaea meaning ‘under the earth’.

Peanuts actually play a lot of roles in health and medicine. In terms of nourishment, peanuts are a great source of protein. They are richer in protein than soy beans and just two tablespoons of peanut butter has more protein than an egg. They also contain nearly 50% fat- but don’t worry! 70% of that fat is unsaturated so whilst that still makes them rather calorific, they are a very good source of energy. Mineral content such as potassium, phosphorus, iron, zinc, copper and magnesium is also proportionately high in peanuts. Finally, peanuts have a lot of vitamin B.

In relation to medicine, peanuts are rich in resveratrol which has antioxidant properties. This helps control cholesterol and prevent heart disease. Peanuts also have an abundance, it seems, of genistein which is known to combat PMS and also prevent the development of cancer cells. One of the many amino acids in peanuts is tyrosine. Tyrosine is used by our bodies to make dopamine, also known as one of the ‘happy hormones’. Lack of dopamine is actually associated with ADHD (attention deficit hyperactivity disorder) in children which can cause problems at school. However, as with everything in life I would not recommend a huge intake of peanuts just for these health benefits as anything in excess can be harmful.

Speaking of harmful, what is a peanut allergy and why does it happen? A peanut allergy occurs when the body’s immune system mistakenly believes that peanuts or something in the peanuts are harmful, so produces an immune response to attack those allergens. During an allergic reaction, histamine is released by mast cells which are found in connective tissues, like the skin. One of the effects of histamine is that it causes capillaries to become more permeable to white blood cells. As a result, fluid moves out of capillaries creating symptoms like watery eyes and runny noses.

Antihistamine can be used to relieve the symptoms of a mild allergic reaction but in a severe reaction anaphylactic shock can occur in which case emergency medical treatment or an injection of epinephrine (adrenaline) as advised by a doctor is required. The best treatment is to steer clear of peanuts if you’re allergic. Although peanuts are not a nut, as we recently found out, if you have a nut allergy you are likely allergic to peanuts too (and visa versa). This is because the allergens are similar so the body responds in the same way.

So that’s a bit about peanuts and nut allergies, but also about some of the benefits of the superfood too. With over 40 million tonnes of shelled peanuts produced worldwide, peanuts are indeed a very popular foodstuff, whether they are a nut or not…

Peanut or Pea-not?

The humble peanut is much loved around the world, making up 67% of all nut consumption in the US and can be found as an ingredient in a ridiculous number of foods or eaten as a savoury snack. Unfortunately, peanut allergy is also one of the most common food allergies with about 1 in 100 people in the UK being allergic.

My interest in this topic arose when someone broke the news to me that the peanut is not actually a nut. Okay, so maybe not the most ground-shaking piece of information but a surprise to me all the same. Turns out, the peanut is actually a legume. This is because a nut is considered to be a fruit whose ovary wall become very hard at maturity, hence the phrase “tough nut to crack”. Also, nuts tend to grow on trees. In contrast, peanut pods split open when ripe and they grow underground. In fact, they are scientifically classified as Arachis hypogaea with hypogaea meaning ‘under the earth’.

Peanuts actually play a lot of roles in health and medicine. In terms of nourishment, peanuts are a great source of protein. They are richer in protein than soy beans and just two tablespoons of peanut butter has more protein than an egg. They also contain nearly 50% fat- but don’t worry! 70% of that fat is unsaturated so whilst that still makes them rather calorific, they are a very good source of energy. Mineral content such as potassium, phosphorus, iron, zinc, copper and magnesium is also proportionately high in peanuts. Finally, peanuts have a lot of vitamin B.

In relation to medicine, peanuts are rich in resveratrol which has antioxidant properties. This helps control cholesterol and prevent heart disease. Peanuts also have an abundance, it seems, of genistein which is known to combat PMS and also prevent the development of cancer cells. One of the many amino acids in peanuts is tyrosine. Tyrosine is used by our bodies to make dopamine, also known as one of the ‘happy hormones’. Lack of dopamine is actually associated with ADHD (attention deficit hyperactivity disorder) in children which can cause problems at school. However, as with everything in life I would not recommend a huge intake of peanuts just for these health benefits as anything in excess can be harmful.

Speaking of harmful, what is a peanut allergy and why does it happen? A peanut allergy occurs when the body’s immune system mistakenly believes that peanuts or something in the peanuts are harmful, so produces an immune response to attack those allergens. During an allergic reaction, histamine is released by mast cells which are found in connective tissues, like the skin. One of the effects of histamine is that it causes capillaries to become more permeable to white blood cells. As a result, fluid moves out of capillaries creating symptoms like watery eyes and runny noses.

Antihistamine can be used to relieve the symptoms of a mild allergic reaction but in a severe reaction anaphylactic shock can occur in which case emergency medical treatment or an injection of epinephrine (adrenaline) as advised by a doctor is required. The best treatment is to steer clear of peanuts if you’re allergic. Although peanuts are not a nut, as we recently found out, if you have a nut allergy you are likely allergic to peanuts too (and visa versa). This is because the allergens are similar so the body responds in the same way.

So that’s a bit about peanuts and nut allergies, but also about some of the benefits of the superfood too. With over 40 million tonnes of shelled peanuts produced worldwide, peanuts are indeed a very popular foodstuff, whether they are a nut or not…

 

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The Science Behind Sleep

UntitledWe spend about a third of our lives sleeping, and many aspects of it remains a mystery to scientists but what they do know is that it is very important in brain development, muscle repair, memory consolidation and growth.

Historically, sleep was thought to be a way of conserving energy however the energy actually saved is minimal and sleeping for 8 hours only actually saves about 50kcal- the same amount of energy as a slice of toast! Another theory is that the sleep period keeps animals safe at a time of day most dangerous in terms of predator encounters. However, the lack of consciousness and response to stimuli leaves sleeping animals vulnerable so this theory is also not very strong.

The more widely accepted theory is that physical restoration occurs during sleep. During REM sleep, the majority of what happens is brain repair, restoration and development whilst non-REM sleep is mainly devoted for body repair and restoration. Many studies also show how sleep improves long-term memory processing and converting short-term memories into long term.

 

Sleep is generally split into REM and Non-REM (NREM), in which the NREM is sub-split into 3/4 other stages. NREM makes up about 75% of sleep whilst REM has the rest- in adult. Infants spend closer to 50% of sleep time in REM.

Stage 1 of NREM is Light Sleep, a state between asleep and awake. In light sleep muscle activity slows down, breathing and heart rate begins to slow down and people can be easily awoken. In stage 2, sometimes known as True Sleep, breathing and heart rate are regular, body temperature drops (by about 1o) and awareness of surroundings begins to fade. A sleeper spends more time in stage 2 than in any other.

Stages 3 and 4 are often lumped together as Deep Sleep. Breathing and heart rate reaches their lowest levels and responsiveness to the environment reduces even further. There is no eye movement or muscle activity and most of the information processing and memory consolidation takes place in deep sleep- although it does to some extent happen in stage 2 and REM. Stage 3/4 is where tissue growth and repair happens and hormones like growth hormone is released. Children may experience night terrors, bed-wetting or sleep walking during deep sleep.

Following Deep Sleep we move into REM which stands for Rapid Eye Movement. These side-to-side eye movements are intermittent and considered to be due to images seen internally during dreaming. The majority of dreams happen during REM although scientists do not know why we dream. Unlike in NREM, heart rate and blood pressure increases and breathing becomes faster and irregular. What’s more, most muscles become temporarily paralyzed during REM as brain impulses which control movement are suppressed. This is called atonia, and is thought to prevent us from acting out our dreams and possibly hurting ourselves. This theory was developed by Michel Jouvet who stopped this atonia from occurring in an experiment on cats, and consequently observed that the cats would physically run, jump and stalk prey during their dreams.

The first occurrence of REM lasts for around 90 minutes before the whole cycle begins again. Recurrence of REM becomes longer whilst periods of deep sleep become shorter over the course of the night.

 

So that’s what happens each night when you fall asleep, it’s not as simple as just ‘being unconscious’ as your body takes that opportunity to store memories, heal and dream. Watch this space for a follow up post on how to get that much needed sleep!

 

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The Science Behind the Sun

As we approach Easter time, many of us will be noticing the blooming flowers and longer, sunnier days- for many of us, a reason to rejoice! The better weather definitely seems to cheer people up and boost ice cream sales, and whilst most people know to some degree that catching a bit of sun can both benefit and harm health, sun protection advice is increasingly ignored by teens wanting to tan and children wanting to play out in the sun. So I’m here to educate and tentatively advise a little bit about the sun.

 

As most people can confidently tell me, sunlight is a great- the best, in fact- source of vitamin D. But what is vitamin D? For one thing, it’s not technically a vitamin. Vitamins are generally defined as organic chemicals that are obtained from a person’s diet because they’re not produced by the body. Yet vitamin D is produced by the body and about 90-95% of it is obtained through sunlight. Also, it isn’t found in any natural foods except egg yolks and fish. Still, old habits die hard so it’s referred to as a vitamin even so.

Vitamin D is obtained from sunlight by using the sun’s ultraviolet B energy to turn a chemical in your skin into vitamin D3. D3 is then carried to your liver and kidneys, each time picking up oxygen and hydrogen molecules, to finally become 1,25(OH)2D aka calcitriol or vitamin D.

Now what vitamin D actually does is a bit more interesting. It’s best-known role is to keep bones healthy. The way it does this is by increasing the amount of calcium that can be absorbed in the intestines. Without enough vitamin D, the body only absorbs 10-15% of the calcium in our diets whilst 30-40% can be absorbed with the right amount of it. It also helps the body to absorb phosphate in our diet, which is also required for bone health.

Without sufficient vitamin D, bones can become soft and weak leading to bone deformities like rickets in children. Rickets is no longer as common as it used to be, but it causes bone pain, poor growth and deformities of the skeleton.

 

Sunlight has many other benefits, such as mood improvement. Exposure to sunlight can increase the brain’s release of the hormone serotonin, which is associated with mood boosting and a deficit of serotonin can lead to depression. There is also a correlation between the number of deaths from heart disease in the summer as opposed to the winter suggesting that the sun can reduce heart disease. UV radiation from sun exposure can be used to treat eczema (dry itchy skin), jaundice (yellowing of skin and whites of eyes) and acne and is sometimes recommended by doctors if they think light treatment would help. Finally, a moderate amount of sunlight may prevent cancer. According to a study from Environmental Health Perspectives, people who live in areas with less sun/daylight hours are more likely to have a variety of cancers including ovarian, pancreatic and colon cancer. However, too much sun can also cause cancer so it’s important to get the right balance.

 

As too many people have experienced first hand, staying out in the sun too much without protection can cause sunburn which not only is painful but also increases your chance of getting skin cancer. Sunburn is caused by the UV light from the sun which can damage the DNA in cells. As a result, the cell with damaged DNA ‘commits suicide’ (apoptosis). Cancer can occur if cells with damaged DNA do not die as they should, but instead continue to multiply. According to the Skin Cancer Foundation, people who have had 5+ sunburns have twice the risk of developing skin cancer. Another thing to be aware of is you can still get sunburnt in the UK and/or if it’s cloudy.

 

Heat exhaustion and stroke are two other serious conditions that can happen when you get too hot, sometimes from being in the direct sun but other times just from being in a hot climate.Heat exhaustion describe the condition in which you become very hot and begin to lose water and/or salt from your body leading to feelings of weakness, dizziness, sickness and various other symptoms.

If heat exhaustion is not treated it can lead to heatstroke, which is when your body can no longer cool itself so your body temperature becomes dangerously high. This puts a strain on multiple organs including the brain, heart and lungs and can be life-threatening. If you have heatstroke, symptoms of heat exhaustion can develop into more serious symptoms like seizures (fits) and loss of consciousness.

If a person displays signs of heat exhaustion, you should try to cool them down by moving them to a shaded or air conditioned area, using a wet flannel to cool their skin and rehydrating them. However, the best advice that can be given is to not get heat exhaustion, heatstroke or sunburnt in the first place.

 

To ensure you are safe in the sun, you should spend time in the shade when the sun is at it’s strongest (between 11am-3pm in the UK) and use at least factor 15 suncream. Even if you are wearing water resistant suncream, it should be reapplied after you’ve been in water or if you’ve been sweating. You should protect your eyes using sunglasses with the CE mark and wear a wide-brimmed hat to shade your face and neck. Children are especially at risk as their skin is more sensitive than adult skin, so children should be encouraged to play in the shade, cover up in loose cotton clothes and wear lots of suncream. Finally, you should not spend a longer time in the sun wearing suncream than you would normally spend without it- my mum’s general rule of thumb is to limit it to 20 minutes of being in direct sunlight at any one time.

 

Whilst the sun does present some dangers, it’s warmth is also essential for human life to even exist and I still encourage you to enjoy it this spring and summer. All I ask is that you do so sensibly, because no sane person enjoys sunburn and heatstroke.

 

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Does the 5-second rule really work?

I’m sure you’re familiar with and maybe even ‘daring’ enough to use the 5-second rule, but a news article this week has brought this question to my attention as Professor Anthony Hilton has decreed that it’s indeed true, to a degree. For those of you who actually don’t know what it is, the 5-second rule suggests that if food is dropped on the floor, it can still be eaten if it is picked up within a window of 5 seconds.

 

Notably since 2003, scientists have been making attempts to prove or disprove this theory with Jillian Clarke starting the proceedings by proving that foods will be contaminated- even with brief exposure- to a floor inoculated with E.coli. She did, however, also find that there was little evidence that public floors are in fact contaminated. In 2006, another study found that bacteria could thrive under dry conditions for over a month and that contamination does increase as the food is left on the floor for longer.

Researchers at Rutgers University tested extensively using different surfaces and foods with a total of 2,560 measurements to find that wet foods pick up more contaminants than dry, and that carpet is surprisingly a better surface than steel or tile when it comes to transference of bacteria. Lead researcher Professor Schaffner states, “Bacteria can contaminate instantaneously” and the evidence agrees, but does that answer the question?

As previously mentioned, Anthony Hilton at Aston University led a study in 2014 which found much the same as Schaffner’s yet suggests such results support the 5-second claim. Whilst he accepts that bacteria is inevitably picked up and that eating food from the floor is never “entirely risk-free”, he also points out that the research shows food is unlikely to pick up harmful bacteria from the few seconds spent on the floor. Furthermore, he has said there should be little concern about food that has touched the floor for such a short time. I think that this conclusion rings true with more of the general public than the latter, with 79% of 2000 people admitting to eating food that had fallen on the floor.

 

My view is that most people do not truly believe zero bacteria is picked up in those precious 5 seconds, but assume that the amount is negligible and neither numerous nor dangerous enough to cause any harm. The science does show that the longer food is on the floor, the more bacteria is picked up and in those first 5 seconds any harm from said bacteria is unlikely. Therefore, I would argue that the 5-second rule does work, but really it is up to personal preference and circumstance. But if you’ve dropped a slice of watermelon (made up of 97% water) on a visibly dirty tile, I’d say give it a miss- it’s just common sense…

 

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The Science Behind Clinodactyly

The word ‘clinodactyly’ stems from the Ancient Greek meaning “to bend” and “digit”, and that is basically what this genetic abnormality is. I first became interested in this when I noticed my younger sister’s little finger was bent inwards, although until now I’d always assumed that it was nothing…

 

Clinodactyly is the medical term used to describe when a finger or toe is curved or bent at an angle, usually with an incline between 15° and 30°. The condition affects about 10% of the population and is passed on through inheritance. It may present either as an isolated anomaly or as part of an associated syndrome, for example a significant percentage of individuals with Down syndrome also have clinodactyly. The condition occurs more in boys than girls and is visible as soon as the child is born.

In most cases, clinodactyly is caused by the growth plate in the hand (or foot) being an abnormal shape or having an abnormal orientation, so the bones do not grow at 90° to the finger axis. Treatment is only necessary if the digit is bent enough to cause disability or emotional distress, in most cases a person with Clinodactyly can use their hands or feet normally. If surgery is required due to inference with function, the procedure involves making a small incision on the affected finger or toe and cutting the bone to correct the deformity. The finger is then stabilised until the bone and soft tissue has healed. Most of the time, surgery is successful however there is a risk that the digit reverts resulting in the need for future surgery.

 

So that’s just a short and simple post about a minor abnormality that you’re likely to see everywhere, now that you know about what you’re looking for.

 

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The Science Behind Popcorn

London Empire

Ever wondered why popcorn pops? Or how a little kernel of corn becomes a tasty snack with just a little bit of heat? Well, whether you have or not I am about to explain the science behind popcorn!

 

First, how does the kernel become popcorn? The kernel is made up of three parts; the pericarp, germ and endosperm. The pericarp is the outer shell surrounding the kernel which is the key to making it pop, and the endosperm contains some trapped water-as well as starch granules which serve as food  for the germ when it sprouts.

Anatomy of a kernel

When heated to above 180°C this trapped water expands into steam, building up pressure inside the pericarp. This steam transforms the soft starch grains in the endosperm into gelatinous material, making it softer and more pliable. When the pressure builds up to above 930 kPa, the pericarp ruptures thus releasing the steam and gelatinous starch (basically turning the kernel inside-out) that solidifies when cooled.

 

So that’s what’s happening in the microwave, but when does the familiar popping sound occur? A study carried out by two French physicists shows the sound is caused by the release of the water vapour. The sudden change in pressure when the steam escapes causes the cavities in the kernel to vibrate and produce that ‘pop’ sound. The researchers also found out why popcorn flies about whilst being cooked, and it’s not actually due to the pop sound. From the ruptured pericarp, a ‘leg’ shaped structure made of starch forms which is compressed under the heat, and then propelled into the air by the ‘leg’ as it expands. The shape of this jump actually mirrors the movement of a gymnast doing a somersault!

 

Popcorn is the only grain in the corn family that pops when heated in this way, but we all know that not every kernel does pop. At the bottom of every bag of popcorn, there’s a handful or less (if you’re lucky) of unpopped popcorn kernels, but why? To start, the optimum percentage of water in kernels for best popping is 14%. Any lower, and the kernels are smaller and fewer will pop. Most popcorn is harvested in the autumn with a moisture level of 16-20% but are then dried out by forced air to reach that optimum level.

Another thing to think about is the structure of the pericarp. In a study comparing 14 different genetic varieties of popcorn they found that best popping kernels had a stronger, more ordered crystalline structure of cellulose (which is what the pericarp is mostly made up of). This is because during heating, the pericarp acts as a pressure cooker that locks the steam inside the kernel until enough pressure builds up for the kernel to rupture and pop. The researchers showed that the stronger crystalline structure tended to maximise moisture retention, leading to a more complete rupture and fewer unpopped kernels. How this information can be used to ensure that we find fewer kernels at the bottom of the bag isn’t clear, but possible techniques include selective breeding of the best kernel varieties or genetic engineering of the corn plant.

 

Regardless of those few disappointing kernels, popcorn is one of the world’s favourite snacks with some nutritionists calling it a perfect snack food because it is whole grain, a source of fibre and low in fat. It also has more protein that crisps gram for gram and is a great way to stave off hunger cravings as it’s mostly air. So treat yourself with this fabulous snack and listen out for that snap, crackle and most importantly: pop!

 

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