Greetings everybody

I have been doing this amazing free online course with Future Learn called 'Preventing the Zika Virus' and so far this has been mind blowingly amazing! One of the best parts of it for me was looking into Vector Biology. By that I mean looking into the biology of the insect or organisms that harbours the virus and transfers it to an unsuspecting host. In Zikas case the vector is a genus of mosquito known as the Aedes mosquitoes and these are the guys that are going to get all the attention in todays post. Enjoy!

By Aedes mosquito I do not mean the entire genus is contributing to the current Zika epidemic. It is actually two of the most common forms of Aedes Mosquito lets meet the culprits: 

Aedes aegypti:

This mosquito has not only been implicated as a vector for Zika but also in: 

• Dengue virus
• Yellow fever virus
• Chikungunya

It has also been shown to be capable of transmitting the West Nile Virus as well as Venezuelan Equine Encephalitis virus. 

Like other mosquitoes A. aegypti is made up of the basic body parts; the head, the thorax and abdomen. On their tiny heads you will find two compound eyes, antennae (that are extremely sensitive to chemical signals) and of course a mouth part. Interestingly it is only female mosquitoes we have to worry about as males often feed on blades of grass! The females are the blood suckers. 

A. aegypti most unique feature that makes it possible for possible identification is their violin shaped pattern located on their thorax (circled in red).

Below is a picture of this mosquitoes distribution. 

Looking at the map there are several points that can be used to explain why A. aegypti is found in certain areas: 

• Temperature is a key factor playing into this mosquitoes distribution pattern. 
• A.  aegypti is not found in areas with cold temperatures at high latitudes or elevations which describes why it isn't commonly found in many areas of the northern hemisphere. 

Females suck blood for the development of her eggs this twinned with A. aegypti strong preference for human blood! and not animals making them an important vector for human diseases. 

Aedes albopictus

Also known as the Asian Tiger Mosquito, a name given due to the white banding patterns. This mosquito has been implicated as being capable of transmitting the same viruses as its fellow genus member Aedes aegypti. 

Looking at this guy you are probably thinking they look strikingly similar to the A. aegypti mosquito in both colour and the white bands on their body. However, the devil is in the detail. There are differences in the size with A. albopictus being 2-6mm smaller in length with a single silvery white stripe running down the middle of its back. 

Another major difference is the distribution of this mosquito: 

What can we gather from this? 

• It shares a lot of its distribution with A. aegypti. 
• A. albopictus is able to tolerate a lower temperature and this can be seen by its ability to establish itself more in Northern America and areas of Southern Europe!

Females of this genus have shown a preference for domestic and wild animals as potential blood bags. Of course they still bite the occasional human. 

The success of Aedes and how the Zika virus exploited it: 

A lot of success for these mosquitoes is from a certain stage within their life cycles (see below) 

These mosquitoes have adapted their life cycles to suit the modern environment created by us. Modernisation has led to a lot of waste production. Empty containers or cans with small amounts of water  are a perfect place for these mosquitoes to lay there eggs. Wide availability of optimal egg laying locations means that the females do not lay eggs all in one container but in many containers over great distances. 

Aedes albopictus have tailored their feeding habitats to just about everything including the creatures that also profit from our waste cultures such as rats, foxes and even lizards in tropical areas. Whereas Aedes aegypti has decided to stay on a strict human blood diet (anthropophilic). 

Thats not all! Unlike many other mosquito species these females eggs are able to survive very long period of time in dry conditions. This ability to survive long period of desiccation would have allowed them to be transported in cargo providing them access to new unchartered territories... once they become rehydrated. 

For the Zika virus it is able to exploit this adaptability to colonise new areas as well as take advantage the A. aegypti's love for our human blood.  

Well that was this weeks post everybody I hope you have enjoyed learning a little bit more about the Zika virus and its partners in crime.

Have an awesome weekend 

Biobunch, 

Over and out

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Greetings everybody

It is that glorious time of the week again - Friday! Interesting week for the UK with the second female Prime Minister accepting her role. Enough about Politics it is the post you all love reading for little bit sized chunks of knowledge. Enjoy guys. 

Some great facts up top, I hope you enjoyed them and that you feel you could use them as a conversation starter... you never know so go and impress someone with some awesome Science facts. 
Have an awesome weekend everybody, 

Biobunch
Over and out

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Greetings everybody!

Hope you all have had an amazing week! Students from around the world you are so close (if not already there) to your summer holidays! 
The title of this post is pretty distressing, and I know you must be thinking what could be driving this possible apocalypse. Articles published last week alerted the public to a disease that has the potential of spreading through Europe like wildfire - Prion disease. This weeks post is going to shed some light on this disease that has snuck its way up in the ranks as one of natures deadliest.

What is Prion disease?

When it comes to this disease, it is all in the name. Take a look below at how the name Prion came into being. 

Prion disease is an infection of our bodies proteins. This disease takes responsibility for neurodegenerative diseases known as Transmissible Spongiform Encephalopathies. The term pathogen is used by scientists to describe a disease causing organism. Prion disease is a bit trickier to classify. Prions are infected proteins, therefore they are not alive, similar to viruses that cause diseases such as the flu. Viruses like other pathogens  (bacteria and microorganisms) have basic genetic units such as DNA and RNA, Prions however do not. 

Common Prion diseases include Chronic Wasting Disease, Bovine Spongiform Encephalopathy and Creutzfeldt-Jakob disease. All these disorders are characterised with the formation of plaques (buildup of mis-folded proteins).

What are Prions?

Prions are a naturally occurring group of proteins found in animals and humans. It all starts with a newly synthesised normal prion protein. Many of these protein structures are carefully formed from a sequence of amino acids that fold and twist to give the shape related to the proteins function. However, if these proteins were to refold to form a new shape their metabolic value would be lost. 

When the prion protein changes shape it acts as trigger causing neighbouring healthy proteins to hop on the band wagon and  take on a deleterious form of the protein. This continues to form congregations of deformed prion proteins   within the infected individuals brain. At this point typical symptoms include weight loss, coordination problems and behavioural changes.

Prions role in European natures apocalypse: 

Diseases caused by the development of malformed prion proteins can be extremely contagious and are always develop into fatal brain conditions. Europe had its first confirmed case of Chronic Wasting Disease (a form of Prion disease). On a  routine tracking project on reindeer a team of researchers in Norway spotted an individual suffering from an illness and later died. They brought the individual back for  examination where it was confirmed that this individual was a victim of a Prion Disease that affects Cervids. 

This was officially the first time that Chronic Wasting Disease was ever reported on European soil and the first time to be documented in reindeer. CWD is common in regions such as North America and South Korea affecting the deer and elk in the area. This disease it believed to be transmitted by deformed prion proteins being shed in infected individuals saliva, faeces and urine. This is yet to be confirmed, and with regard to other prion diseases the Centre for Disease Control is unsure whether transmission is caused by physical contact or indirect methods such as food and water sources. 

Questions are racing through everybody's minds. Was it an isolated case or has it remained undetected in nature and is far more widespread than we could imagine? Prion diseases such as Chronic Wasting Disease and Bovine Spongiform Encephalopathy (Mad Cow Disease)  remain subtle in the initial stages of infection and therefore are easy to miss. If this disease is more widespread than expected Europe's nature is in trouble because once taken hold it is extremely hard to eradicate. 

Conclusion...

The UK voted Brexit. We may no longer be part of the European Union but diseases such as the Prion disease or the countless other diseases will not respect our borders. Collaboration is needed now more than ever in the management of future diseases. In regards to the Prion disease if it is more widespread it is likely to eek its way up the food chain reversing all the amazing work the UK and Europe has done to increase its wildlife numbers. Disease management requires lots of information such as transmission is it contagious or infectious? Is there a possibility that it could cross the species barrier and affect humans? This remains unknown and therefore hinders management and detection of the disease in nature. 


Well guys that was that! Have an awesome weekend everyone and I will see you next week. 

Biobunch
Over and out

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Greetings everybody!

It is a very, very special Friday today. Not only because its pinch- punch 1st day of the month... but because you are reading the 100th post published on this amazing blog! 100! That is such an awesome number, so I would like to say a massive thank you to all of you who have kept reading the blog it means a lot to me. 

Enough mushy stuff lets get to the science. Todays post was inspired by a GCSE chemistry topic that carries some major biological potential. Nano science. 

What is Nano science?

Nano-science is the study of structures on a nanoscale such as those seen in the above picture. Structures such as the Micelle,  Liposome, Gold Nanoshell, etc. are classified as nanoparticles measuring 100 nanometers or less across. According to an article published in Science News that is equivalent to a 'thousandth the thickness of a dollar bill'. Crazy small right?

Nano may indicate their size but their effect once inside the body is anything but. Scientists realised that due to their size these particles are able to penetrate deeper than any medicine on the market, opening the door to better medicines and diagnosis. 

When using nanoparticles scientists have a major decision on their hand- what one to use? Interestingly, the properties of nanoparticles vary widely from their full sized counterparts   take Gold as an example when smashed into Nano Gold Particles they become red! After the selection process is complete and you have your nanoparticle you now have to engineer them to carry out a role once inside our body. These roles can be anything! From express delivering drugs to target cells deep in our tissues or fit them with colourful or fluorescent tags that allow you to spot tumorous growths or blocked vessels. 

The possibilities are endless with nanoparticles! For this post however I am going to focus on two major medical applications for this technology. 

How do they work?

Atherosclerosis

Atherosclerosis is a common condition suffered by people with cardiovascular disease. It occurs when the bodies blood vessels (arteries, veins and capillaries) become blocked by fatty deposits on the vessel wall (in the picture below) 

Here is a fun fact 4.55 Litres of blood is pumped through your heart every minute. Take a minute to think about that, and your heart has just pumped 4.55 Litres of blood- again. Once pumped our blood is set on a circuit determined by our bodies circulatory system. In healthy people this is a very smooth journey, however, if you suffer from cardiovascular disease this smooth journey is suddenly riddled with barriers. 

These barriers are of course those fatty deposits mentioned earlier. Over time they begin to form plaques on the vessel walls, this causes the walls to become thicker and less flexible. This process triggers the release of distress signals that are answered by our bodies immune cells. However, the presence of these cells along with the cells in the blood further exacerbate the problem by forming a larger blockage  and further reducing blood flow. 

Vessel blockages have major implications for patients especially if they form in vessels leading to the brain or heart as these could lead to a stroke or a heart attack.

Treatment for this condition is mainly prescribing Statins. This medication doesn't solve the problem but it aids in the management of atherosclerosis by lowering circulating cholesterol a major contributor to the formation of plaques. However, this treatment comes with an increased risk of Diabetes and Liver damage. Nothings perfect.  

This will all change! With the help of nanoparticles. Scientists have been engineering nano missiles that will carry out search and destroy tasks for plaques! They can do these in four ways: 

1. Immune cells respond to distress signals released from blood vessels affected by plaque formations. Once there they attempt to clear the blockage by binge eating the fats gradually becoming a 'foam cell' they send signals of more immune cells to join the bingeing session. Such a build up of immune cells can be used as a biological signpost for nanoparticles to home in on target vessels. In animal studies nanoparticles prevented the  bingeing session entirely and in doing so reduced blockages by 37%.  

2. Engineering nanoparticles to masquerade as HDL. High density Lipoprotein (HDL) is the bodies 'good cholesterol'. It breaks down plaques and transports the debris to the liver where it is broken down. HDL also stops immune cells from forming 'foam cells'. 

3. Statins are not down and out for the count, in fact nanoparticles may catapult them to the front of the line for atherosclerosis treatment. Willem Mulder has designed his particles to deliver statins directly to the plaques. This approach allows for the drug to be administered at a a lower dosage but with a larger effect! 

4. Melina Kibbe has made the blood vessel wall her nanoparticles prime target. Vessels affected by atherosclerosis become damaged and stretched exposing a key structural element called collagen. Her nanoparticle has a protein capable of binding to the target (exposed collagen) attached to nitric oxide. Nitric oxide is a chemical that once in the body trigger the growth of new cells in wounded areas. However, she did not stop there she also changed her nanoparticle from the characteristic spherical shape to a nano fibre in order to increase the surface area of the particle. 

With clinical trial looking very promising nanoparticles could offer a way out of surgery for patients carrying a high risk of heart attacks or strokes as a cause of atherosclerosis. 

Cancer

Globally, the majority of deaths caused by cancer are preventable. Prevention strategies such as vaccination programmes, routine screenings make use of some of our best technology and tools but they carry a major limitation. The majority of cancers can remain undetectable for the first 10 years inside a patient at this time tumours can be some 50 million cells strong. Clearly, innovations in cancer treatment as well as cancer detection are required. Such innovations could lie in our nano sized friends. 

This incredible woman on this TED talk I watched used nanoparticles to detect the presence of tumours- this is how it works. Cancerous cells are the ultimate weapon. They are tough and stubborn because they are your cells gone haywire. Like our cells they need a good blood supply to sustain their crazy growth rates. A cancers blood vessels however, are leaky allowing a clear access point for nanoparticles.

When it comes to biology, size does matter.  A nanoparticles size largely dictates where in the body it has access to and where it does not. This nanoparticle was designed to become activated when cancer cells produce an enzyme essential for their success. In addition to this the nanoparticle was also engineered to make detection as simple as possible. When activated by the cancer enzyme the nanoparticle produces a signal that is deposited in the urine. Similar to how a pregnancy test is used, the presence or absence of this signal can be detected from a patients urine.

This nano detecting particle will be able to pick up on even the earliest stages of cancer. 

It is difficult for our bodies immune system to eliminate cancer cells because at the end of the day cancerous cells are our cells. This allows cancer to exploit the lesson taught to all of our immune cells- do not destroy our cells.  Tumours also surround themselves in their own micro-environment,  this simulates the illusion that there is nothing to worry about further throwing immune cells of their attack path. 

The authors of an amazing study featured in Nature  managed to implant a nanoparticle with tumour RNA (carries information of the tumours DNA) and injected it into animals. Once inside the body these engineered nanoparticles carried the tumour RNA to special tissue that contain large numbers of immune cells. Once there the nanoparticles activate the immune cells by simulating a viral invasion inside the body. Activation of these immune cells leads to the activation of the big daddy immune cells known as T cells. Once they have been told how to recognise the tumour cells in the body they are primed and ready to unleash their anti tumour response by eliminating it! 

This is such a promising study for the future role nanoparticles have to play in the fight against cancer.  

Well that was it guys! The blogs 100th post hope you enjoyed it and that you have a greater understanding of nano science!

Science is so amazing the phones went through a miniaturisation age I suppose it was bound to happen for science to. Of course these are in early development and whether using nano particles carries any long term effects on the human body remain unknown. For now it is comforting to say that this branch of science is extremely promising. 

Biobunch, 

Over and Out

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