How many times have we seen a story about how a compound that increases the immune system may help fight cancer (I’m looking at you Daily Mail)? Whilst often we recognise these stories as over-glamorised and technically false, there is an assumption made that is rarely challenged; that the immune system regulates cancer. This assumption is false and based on misinterpretations of old studies.
In studies of both immune suppressed humans and mice, it was found that there was no major difference in occurrences of cancer compared with humans and mice with normal immune systems.
There is one exception to this finding; cancers associated with viral infections. It is found that tumours with a known viral cause are more likely to be found in those with a compromised immune system (cancers such as Kaposi’s Sarcoma).
This can be turned on its head. If a type of cancer shows different rates in individuals with normal immune systems and those with compromised immune systems, then it is likely to have a viral influence.
Image below of Kaposi’s Sarcoma
The last case of wild polio in the WHO Region of the Americas occurred in 1991. Indeed it was the last case of wild polio in the western hemisphere. His name was Luis Fermin Tenorio. At the time of contracting polio he was three years old and was currently living in Junin, Northern Peru.
Image shows Luis Fermin Tenorio (centre).
Image source: www.paho.org
First Updates, then Science.
I’m now contributing to a blog on plant sciences called PLANeT. The link is http://cambridgeplanet.wordpress.com . Its a really awesome project and a load of cool people are involved so it’s worth checking out. Like totally.
Now Science! Sometimes when male deer fight, their horns become entangled to such an extent that they are unable to break free. The obvious and sad conclusion is that they starve to death. Don’t believe? The picture below shows the result of such a misfortune a while down the line.
Image source: http://i.imgur.com/9aUqnZg.jpg
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Listeria monocytogenes is an intracellular pathogen that causes listeriosis and is one of the most virulent food-borne pathogens in the world. Unlike species of Salmonella, Listeria monocytogenes actively moves through it’s host cell.
How does it do this? By means of Actin assembly-inducing protein (ActA). ActA is is found at one end of the bacteria only, and induces host actin polymerisation.
This causes the bacteria to be propelled forward and results in the production of Actin Comet tails, which can be viewed by fluorescence microscopy. The resulting image is surprisingly beautiful.
An image of this phenomenon can be viewed below, the actin is green and the listeria are orange/red.
Image Source: http://labrat.fieldofscience.com/
Alternative Title: Little Feathery Psychos—Why you don’t fuck with a Great Spotted Cuckoo
You’ve probably heard about Cuckoo. The go to example for when people need to demonstrate parasites don’t have to be slimy; they can be feathery too.
Parasitic cuckoo’s come in one of two forms. The first is the Common Cuckoo, which lays it’s eggs in the nests of other birds. Upon hatching the cuckoo chick ‘evicts’ the remaining eggs; if any chicks are unlucky to have hatched before the cuckoo then they are also ‘evicted’.
But it’s the second species that takes the metaphorical biscuit for feathered-spawn-o’-satan. They tend to lay their eggs in the nests of magpies, and when the the cuckoo eggs hatch they allow their adopted kleptomaniac brothers and sisters to survive.
"Aha!", you may say, "this proves that they’re lovely birds with nothing but kindness in their little avian hearts."
Wrong. For, you see, the parent cuckoo returns to the magpies nest a few days after laying and, if it finds it’s precious egg missing, goes a little ‘cuckoo’ (pun intended and may the gods of comedy forgive me) and destroys all of the hosts eggs in an extreme case of “If I can’t then no one can”.
This is not a case of blind rage, it is crafty calculation on the Cuckoo’s part. It actually confers an advantage to Great Spotted Cuckoos overall, as it only allows for the evolutionary selection of magpies that allow cuckoo’s eggs to stay.
Further details can be found in this research paper: http://www.eeza.csic.es/eeza/documentos/soler_1004.pdf
Don’t worry it’s not dry as death- they refer to cuckoo’s as the Mafia.
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As a pathology student, the festive season is not a good time for reading; there’s too much "Peace on earth and good will to all men" floating around. Driven out of curiosity/boredom/ curioredom, I searched the internet for "Christmas Disease" and, low and behold, it exists!
Giving proof to the thought that the only consolation of of having a rare disease is the possibility it will be named after you, the disease gains it’s name from the person the disease was identified in: Stephen Christmas. The disease, also known as Haemophilia B, is characterised by a mutation in the Factor IX gene. Factor IX is one of the serine proteases involved in the coagulation cascade; in short, without it your blood doesn’t clot. The condition accounts for 15% of haemophiliacs and even has a royal following—it is the form of haemophilia that afflicted the royal families of Europe throughout the 20th century.
Somewhat humourously, the paper detailing the discovery of the condition was published in the British Medical Journal in 1952 on the 27th of December; the Christmas issue.
In a somewhat sad conclusion, Stephen Christmas died of HIV/AIDS in 1993 after contracting it through a contaminated transfusion; a horrendous fate bore by many haemophiliacs at the time. (This blog post has nothing to do with Christmas trees)
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The final battle against malaria is a battle against vivax.
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How does one figure out the value of Pi? You could draw a circle on some paper/in the ground/ on your friend’s back. But how could you guarantee your circle was accurate? Chances are it would be a little bit off and you would be left with a false value- no matter how accurate you thought it was. One way to solve the problem would be to introduce boundaries, to say that the value of pi is between X and Y.
This was the method undertaken by Archimedes, who knowing how to calculate the circumference of simpler shape, calculated the first estimation of pi. Using simpler shapes to estimate the value of pi is known as the polygon approximation method. The simplest form of this is to use two squares, one just inside the circle and the other just outside (see picture). The larger square will have a side length equal to the diameter of the circle, and so its perimeter will be equal to 4d. The inner square will have the length from one corner to the opposite as equal to the circle’s diameter. The smaller square can then be thought of as being two right handed triangles each with a hypotenuse equal to d. Using Pythagoras’ Theorem it can be found that each of the sides of the small square are equal in length to d/sqrt(2), giving a total perimeter of 4d/sqrt(2) (roughly 2.83d). As the circle lies between the two squares it’s perimeter (or circumference) must lie between 2.83d and 4d, and as pi is related to these two properties by the equation C=pi*d, then pi must lie between 2.83 and 4.
This can be repeated using polygons with more sides for greater accuracy and indeed pi was calculated to 38 places using this method, involving polygons exceeding 4 billion billion sides. Sounds fun.
For once there is no picture credit as produced by me.
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Behold the mighty dinosaur,
Famous in prehistoric lore,
Not only for his weight and length,
But for his intellectual strength.
You will observe by these remains
The creature had two sets of brains,
The one in his head, the usual place,
The other at his spinal base.
Thus he could reason a priori
As well as a posteriori.
No problem bothered him a bit,
He made both head and tail of it.
So wise he was
So wise and solemn
Each thought filled just a spinal column.
If one brain found the pressure strong,
It passed a few ideas along.
It something slipped the forward mind
’Twas rescued by the one behind.
And if in error he was caught
He had a saving afterthought.
As he thought twice before he spoke
He had no judgment to revoke.
For he could think without congestion
Upon both sides of every question.
O gaze upon this noble beast,
Defunct ten million years at least.
This poem by Bert Leston Taylor represents a peculiarity found in some dinosaurs and also illustrates one of the most steadfast rumours in science. Sadly, dinosaurs did not have a second brain (in the true sense of the word) in their rump, though some (such as the stegosaurus) did possess a concentration of nerve cells thought to give some independent control to the tail and rear legs and so allow the dinosaur to remain balanced. Far from being unique to dinosaurs this neural arrangement is also found in some lizards and even ostriches!
Pictured below is an illustration of a stegosaurus skeleton with the approximate location of the primary brain and the false second ‘brain’.
Image source (http://gildedgreen.notart.org)
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Powered flight has only evolved four times in the history of life on earth: in insects, birds, the now extinct pterosaurs, and (of course) bats. Bats hold the distinction of the only mammal capable of flight (and whilst you may argue that flying squirrels can fly, it is in fact gliding or, to phrase it more elegantly, “falling with style”). Numbering at about 1300 unique species, bats make up roughly 20% of all known mammalian species (rodents—numbering at around 2600— make up an additional 40%, leaving everything else, from aardvarks to zebras, occupying only 40%) and can be found on every continent except Antarctica (I like the idea of an Antarctic Bat; it would be white, fluffy, and still trying to pull of the prince of darkness look). The species of bat is the giant golden-crowned flying fox, with a wingspan of up to 1.7m and weighing up to 1.2Kg, and the smallest is the Kitti’s hog-nosed bat, weighing around 2g.
They’re also significant reservoirs of viral zoonoses (diseases capable of transferring between species, from any non-human animal to humans), including Nipah virus, Hendra virus, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS). They are also strongly linked to Ebola and Marburg among others. In fact, it was found that bats carry 61 viruses that can also cause disease in humans (compared to rodents, who at double the number of species, carry only slightly more at 68 viruses). Why bats make such excellent reservoirs of these viruses is hotly debated with evidence supporting their behaviour, their unique immune system, and their sheer numbers (some species of bats can gather into colonies exceeding 1 million individuals). Some also argue that it is their increased contact with human populations due to habitat loss that is too blame. Whatever the reason, when it comes to new and dangerous reservoirs of viral zoonoses, bats are head and shoulders above the rest— and not just because of their ability to fly.
For more information see: http://www.sciencemag.org/content/341/6149/948.full
Pictured below is a rather dashing albino bat— possibly the closest I’ll get to an Antarctic Bat…
Image Source: http://www.lancekingart.com/img/albino_bat.jpg
Dandelions, scientific name Taraxacum, are a common genus of plants with more names than a European royal. The English common name derives from the Middle French dent de lion meaning ‘lion’s tooth. This is the same source for the plants name in many European countries including Italy, Spain, Germany and originates from the distinctly toothed leaves of the plants. Curiously, Modern French uses a name of different origin. Then name pissenlit (meaning piss in bed) comes from the strong diuretic properties of the roots.
Another popular characterisic for naming the plant comes from the latex found in its stem and whilst these names apply to all dandelions, there is only one main species that actually produces latex- the Russian Dandelion (Taraxacum kok-saghyz). In Poland it is known as mlecz, derived from their word for “milk”; in Hungary the plants are known by the name kutyatej (meaning ‘dog milk’), and in Serbia they are name маслачак, which translates as ‘butter’. The name used in Sweden has yet another more ecological heritage; they are called maskros (‘worm rose’) due to the small insects often found the flowers.
Other names are more fanciful or wistful in their inspiration; to Cypriots the plant is known as pappous (παππούς) meaning “grandfather” due to the distinct white seed head that is said to resemble the white hair of an older man whereas to Persians it is called قاصدک (qasedak), which translates as “small postman”, originating from the belief that it brings good news. The diverse geography of the plant means there are many more names and many more origins but to go through all of them would require writing a book of sizeable volume (and if anyone is interested in doing so I would support them and pledge to buy at least one copy) .
Pictured below is an image showing both the flower and the seed head of dandelion plants.
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A quick run through of how to stuff a rat, which can be applied to all small mammals. Apologies for any mistakes, this post is partly for my benefit so that I remember. If this interests you I would recommend going on a short course to see if its for you and to learn first hand ( I highly recommend these guys http://www.curiousmenagerie.co.uk/). Warning: some parts are not for the squemish.
Firstly, what will you need? Good news, most of the items common household goods. You should have:
Scalpel, Scissors, Tweezers, Wire Cutters, Pliers, Spray Bottle, Hair Dryer (Shut up, this totally counts as a tool. Hairdryers are basically real life sonic screwdrivers), Needle, Gloves, Glue Gun.
Rat (Very Important), Cotton wool buds, Wire (thick), Borax Powder, Wood Wool, Epoxy Resin, Thread, Glass Eyes, Washing up Liquid, 50% Methylated Spirits, Tow.
So where do I start?
Checklist checked? First make sure rat (if frozen) is defrosted. Microwaves are a bad idea for doing this. Once defrosted make an incision cutting through he skin but not the flesh from the chest to the bottom of the abdomen (just before the urethra).
Next gently tease away the skin from the flesh using the scalpel to cut the membrane joining the two. Once this is done for the majority of the body and around the hind legs you need to remove the legs from the body by cutting though the ball and socket joint at the hip. When this is done, the leg needs to be removed from the skin up until the ankle until you are left with two little ratty drumsticks.
Legs done, next job tail. First the urethra must be cut (just after the penis for a male) and the rectum (about a cm in from the outside). Next the skin of the tail must gently be pried away from the tail itself, using the scalpel agin to cut the membrane. Eventually the tail skin will just need to be pushed off the tail (kind of like removing the wrapper of a pepperoni) though care must be taken to ensure the tail skin does not inverse.
Once this is done, continue removing skin from flesh and when ready carry out a similar process for the arms as you did the legs (cutting at the shoulder joint this time). After the arms it is time to tackle the head, remove the skin as before cutting off the ears as far inside as possible and cutting the skin between the eyelids and eyeball so as to maintain the eyelids. Stop separating just before the snout is reached. Then cut the head from the body, separating at the point between the skull and the first vertebrae. Keep the body to one side.
You should now be left with the skin with the head and 4 legs attached. The legs must be stripped of as much muscle as possible; keeping only some ‘meat’ around the hinge joint (knees/elbows) and the tendons holding these joints together. The skull must also be stripped of all muscle (except a small amount holding the jaw to the rest of the skull). The tongue and eyeballs must also be removed (you can remove the tongue via the base of the head). The brain must then be removed; this is achieved through wrapping some cotton wool around a piece of wire and scraping it out through the back of the head (where the spine was previously joined). This will likely require you replace the cotton wool several times. Once this is done, you need to remove excess fat from the inside of the skin.
Okay, so I’ve skinned it. What next?
Now that the rat has been skinned, the skin (along with the 4 limbs and skull) needs to be washed in COLD soapy water and then rinsed. After washing, as always, comes drying. Using your trusty hair dryer, dry the outside of the skin (the fur) in the direction of the fur. The skull also needs to be well dried although care must be taken to insure the inside of the skin does not dry out. Next step is to liberally apply (as everything should be done liberally) borax powder to the inside of the skin, to the skull, and to the joints.
Once this is done, sharpened wire should be put through each of the legs so that it exits the skin through the base of the paw. Once exited bend the wire so that it can not go back though the foot. Cotton wool should then be wrapped around the wire and bone so as to recreate the shape of the leg as much as possible (i.e. thin at the bottom and thick at the top) and this is then bound with thread until firm. The front legs will require about half as much cotton wool as the rear legs.
Epoxy resin should then be used to restructure the shape of the head on the skull (i.e. replace the muscle taken away), with excess placed in eye sockets and in the brain compartment. The eyes should then be inserted into the resin so that they sit in a similar place to where the original eyes were as possible.
Next use the wood wool to build a body form of similar size to the torso of the rat (once this is done the rat’s body can be disposed of) and place a short piece of wire at the front and a long piece at the back. Insert the short piece of wire into the rats skull through the hole in the back until the skull sits comfortably against the body form, this can then be joined quicker using a glue gun. Cut the rear wire so it is the size of the tail and using the tow (or cotton wool if no tow available) bulk out the rear wire so it matches the shape of the tail (thin at tip and thick at base). Insert rear wire into the tail. Finally, insert top of leg wire (the part of wire above cotton padding) into the body form at approximately the place the hip/shoulder joints originally were and pull tightly through to other side of body form. Bend the wire in on itself and push end back into body form before repeating for the other legs. Position the piece in the pose you desire and add additional stuffing where required so as to give more naturalistic shape and sow up initial incision resulting in one taxidermied rat. Yay. The rat will then proceed to dry out over the next seven days before being in a relatively stable state.
Important Note: The skin has a tendency to dry out and so must be kept hydrated by regularly applying the 50% Methylated Spirit solution during the process of preparing the skin.
Image Source: wikimedia.org
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It may seem wrong that Mother Nature has prevented man’s carefree best friend from enjoying the finer things in life but death by chocolate is a realistic way to go for our canine companions, so why can’t dogs have chocolate?
It’s because they are particularly sensitive to the alkaloid theobromine that is found in chocolate and metabolise it much slower (it has a half-life in dogs of around 17.5 hours). A compound related to caffeine; theobromine is also a stimulant, although to a lesser extent and acts through inhibiting phosphodiesterase which results in an increased cellular concentration of cAMP (a popular secondary messenger molecule). Symptoms of theobromine poisoning include vomiting, increased urination, diarrhea, unusual heart rhythm, internal bleeding, and heart attacks.
Cats are more susceptible to the effects of theobromine than dogs, however they lack Tas1r2 (Taste receptor type 1 member 2) receptor and so gain no stimulation through eating sweet foods and as such have no motivation to eat chocolate. This results in dogs being more likely to be poisoned than cats.
Pictured below is a very bad idea.
Image source: blog.thebehaviourcompany.com
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As highlighted by a recent film *cough* The Worlds End *cough*, to call a machine capable of independent thought (if such a machine existed) a robot could be seen as insulting. The word robot originates quite recently from the 1923 English translation of the 1920 play R.U.R (Rossum’s Universal Robots) by Karl Capek. The origin of the word robot is from the Czech word robotnik meaning “slave”. This word in turn originates from robota meaning “forced labour, compulsory service, drudgery”, which finds its source from robotiti (translating as “to work, drudge”). The other names suggested by the drunken characters would- though hilarious- would not seem to help in interplanetary relations. ‘Blanks’- which they eventually settle on- would seem to be an even worse name than robots, as at least the word robot recognises the sentience of the machine even if it does deny it freedoms.
So what would be a more appropriate term with which to address the mechanical sentient beings? One suggestion would be android- from the Latin androides derived from Greek andro “human” and eides “form, shape.” The Greek androdes meant “like a man, manly”, though whether or not the machines would appreciate a comparison to humans is another matter.
Another option could be Golem, which gained its current implications in 1897 from the Hebrew golem [Psalm cxxxix:16] “shapeless mass, embryo,” from galam “he wrapped up, folded”. However, calling a rather powerful machine a shapeless mass would probably not lead to any positive conclusions.
Perhaps the naming solution comes from a much older word- automaton. Originating from 1600’s, it is formed from two combination of two Greek words- autos “self” and matos “thinking”. Whilst not particularly descriptive it at least serves the purpose of not having negative connotations.
Or we could always call them Brian…..
Image source: http://www.giantfreakinrobot.com
We’re all familiar with drones. Unmanned aircraft have been a relatively regular presence in the news, usually in debates surrounding the morality of using them in milatary operations or the sheer legality of the operations to which they have been applied. However, despite there reputation as the destroyers of life, drones can also have the potential to be the bringers of life. As is the case with all technology, drones are not inherently evil and it is the application of the technology that is key.
So what other applications besides warfare are there for drones? One area that has been qucik to embrace these machines is that of conservation. The potential of drones has already been used in mapping of rainforest and uses under consideration include aerial sowing of seed to revegetate tropical forests (as a cheaper and safer alternative to sowing by manned aircraft) and targeted application of herbicides and other pesticides.
There you are: are drones bad guys turned good, misunderstood good guys, or just machines limited by our imagination.
For those interested in further reading, here is a link to a paper on the subject:
Image Source: www.fishbio.com
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