Author Archives: gurtaj mahil

SNAPSHOT: A Clearer Picture of the Brain

Cutting, staining and imaging brain slices has been a vital technique to study the brain and its intricate structures. Lasse Dissing-Olesen, a researcher at the University of British Columbia, has produced a simple and effective approach that will allow researchers to view brain slices like never before. SNAPSHOT, as he termed it, literally gives you a picture of a brain slice at that moment in time, preserving its structure.

During an interview, Lasse described his unwavering interest of the brain’s immune system. Lasse talked about the immune cells of the brain called microglial cells and their multiple functions.  Not only are these microglial cells responsible for defending the brain against virus, bacteria and injury, they play an important role in the maintenance of the brain’s neural connections. For Lasse, the prospect of studying the most complex immune system in the human body was just motivation in itself. And for this, he needed a way to image the brain such that he could preserve its morphology.

Here is an image of a microglial cell made possible with the SNAPSHOT method

Here is an image of a microglial cell made possible with the SNAPSHOT method Source: Lasse Dissing-Olesen

Previous preserving methods forced researchers to freeze the brain slices which produced several problems. Firstly, as Lasse alluded to in the interview, freezing brain slices kills the tissue and so live tissue cannot be observed. In addition, freezing the brain slice distorts the structure of the brain because as you freeze it, the water molecules expand. SNAPSHOT provides a solution to this problem. In fact, Lasse does not freeze the brain slice at any point, allowing live, undistorted tissue to be observed.

 Lasse uses this two-photon microscope in the lab to view the brain slices he has prepared with SNAPSHOT

Lasse uses this two-photon microscope in the lab to view the brain slices he has prepared with SNAPSHOT Source: Lasse Dissing-Olesen

The reason why Lasse’s method provides a clearer image is because of better antibody penetration. These antibodies are special proteins that attach to certain cells in the brain slice, for example microglial cells. Given that they have fluorescent markers attached to them, researchers can see these structures underneath a microscope. Since SNAPSHOT provide researchers with better antibody penetration, they will have a clearer picture of the microglial cells as well as other structures in the brain slice. Finally, as compared to other techniques, SNAPSHOT’s simplicity allows it to be completed in an afternoon at a very cheap price.

Since microglial cells are implicated in diseases such as Alzheimer’s, SNAPSHOT may allow researchers to further study how the microglial cells respond to the progression of this mysterious disease. In addition, Lasse talked about how he can mimic injuries such as strokes and then observe how the brain responds; this type of live imaging can help researchers learn much more about what goes on at a microscopic level during such injuries. To conclude, it’s important to note that SNAPSHOT is just one tool that will undoubtedly further the research in the field of neuroscience.

Here is a video illustrating how the SNAPSHOT method can be used to study different types of strokes:

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Below is a podcast talking more about SNAPSHOT’s ability to study neurodegenerative disease:

 

– Gagandeep, Elice, Anne and Gurtaj

Putting a Stop to Antibiotic Misuse: A New Blood Test

Antibiotics such as Amoxicillin are becoming more and more ineffective as bacteria become resistant due to misuse.

Antibiotics such as Amoxicillin are becoming more and more ineffective as bacteria become resistant due to misuse. Source: Flickr Commons Image by: Sheep Purple

If you’ve ever felt under the weather and you need it to go away, you might visit your family doctor. When you get there, you probably tell him you just need some antibiotics and you’ll be on on your way. Unfortunately, scenarios such as this happen too often in today’s society.

Contrary to popular belief, antibiotics are only effective at treating bacterial infections, not viral infections. The issue is that the symptoms between the two infections are indistinguishable to doctors. For this reason, antibiotics are usually prescribed.  According to this article, many family doctors are trained to delay antibiotic prescriptions because  bacterial infections are likely resolve on their own, with time. However, this doesn’t  happen as doctor’s usually succumb to pressure from patients for antibiotics.

So what’s the problem with this medicine? Why can’t doctors just keep prescribing them, anyway? In two words, antibiotic resistance. The BBC explains that bacteria, which are living organisms, have the natural ability to evolve and eventually become immune to the antibiotic. In other words, the bacteria will keep on changing in order to survive the effects of antibiotics. The surprising aspect of this is not the fact that the bacteria is mutating and becoming resistant to antibiotics, it’s how fast it’s happening. The BBC says that this is due to antibiotic misuse, which also includes doctors over-perscribing and patients not finishing the full dosage.

Below is a youtube video by TED-Ed explaining how bacteria becomes resistant to antibiotics

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Antibiotic resistance is particularly frightening if you take into account that the World Health Organization is calling it a global threat.  It is suggested that two key antibiotics no longer work in more than half the people treated. In addition, the WHO warns of  a ‘post-antibiotic era’ where previously treatable infections will begin killing people, as the antibiotics are no longer effective in clearing the infection.

Here is a antibiotic-resistant bacteria which is named MRSA (Methicillin Resistant Staph. Aureus)

Here is an antibiotic-resistant bacteria which is called MRSA (Methicillin Resistant Staph. Aureus) Source:Flickr Commons Image by: NIAID

To slow down this inevitable problem, researchers out of Israel have developed a new type of blood test that can distinguish between bacterial and viral infections within two hours, allowing doctors to quickly determine whether or not antibiotics are even necessary.  The usefulness of this new method is apparent if you realize that current ‘bug’ identification tests can take a few days, according to this article.  As previously mentioned, it is hoped that this will allow doctors to limit antibiotics to patients with bacterial infections while refusing to prescribe to patients with viral infection.

As the research paper outlines, the blood test is quite accurate in distinguishing between the two bugs. It relies on identifying activated protein pathways that are specific to either a virus or a bacterium. For example, the TRAIL pathway is highly activated in viruses but suppressed in bacteria. Although pending randomized clinical trials, this could prevent further misuse of antibiotics by doctors and patients alike; possibly even put a temporary halt to the inevitable ‘post-antiobiotic era’.

A novel blood test has been developed which can distinguish between virus and bacteria, allowing for more accurate treatment

A novel blood test has been developed which can distinguish between virus and bacteria, allowing for more accurate treatment. Source: Flickr Commons Image by: Phillip Jeffrey

The Harmful Sun: Evidence for Post-Exposure Damage

 

Woman applying sunscreen on to her face for maximum protection against the UV-radiation

Woman applying sunscreen on to her face for maximum protection against the UV-radiation of the Sun. Source:Flickr commons. Image by earthlydelights

It is common knowledge that the ultra-violet (UV) radiation from the Sun has the ability to cause skin-cancer. For this reason, many of us make sure to apply sunscreen before we depart for the beach on a sunny day. But is the sunscreen doing it’s job? Is it effective in preventing skin-cancer?

Sunscreen can come in the form of a spray or a creme and is vital for protection from the Sun’s harmful rays. As described in this article, sunscreen functions to protect your skin by absorbing the UV rays, acting as the first-line of defence. The article also mentions that no matter how high the protective power of the sunscreen, not all of the UV-rays will be absorbed and some will ultimately reach the layers of the skin.

As per this BBC article, as these UV-rays make it past the sunscreen, they are absorbed by a component of the skin called melanin. Similar to how sunscreen is the first layer of defence, melanin is the second layer of defence against the sun’s rays. Again, melanin does not absorb all of the UV-rays and some pass through to the deeper layers of the skin. This article says that once the UV-rays penetrate the melanin, they can cause disruption at the DNA-level which may cause skin-cancers.  This is not the whole story, however.

The video by Kevin Boyd through Ted-Ed explains why sunscreen is necessary to prevent skin-cancers:

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According to a new study out of Yale University, scientists have discovered that the Sun’s UV rays have the ability to do damage for more than three hours after exposure. The study found that once the melanin absorbs the UV-rays, it initiates a series of chemical reactions in the skin that produces heat. This heat, it was discovered, is what ultimately damages the DNA, hours after initial exposure to the sun.This is a huge breakthrough as it was not previously known what happens to the UV-rays after being absorbed by melanin.

Yes, the sunscreen that is on the market now still protects against UV rays, however, it does not protect against the post-exposure damage that occurs. So no, the present form of sunscreen is not as effective as it should be. The real-life implication of this study is that now scientists can produce an ‘evening-after’ sunscreen that can be applied after exposure, protecting your DNA from the heat and ultimately preventing cancers.

Finally, a quick note for all those that don’t feel the need for any sunscreen; not only are you putting yourself at risk for cancer when you are in the sun but also for up to four hours later,even if you are indoors. Until this new type of sunscreen is developed, I think it’s essential that we allow for as little UV-rays to get to our melanin as possible. So, lather up!

A sign that reminds everyone to 'use plenty of sunscreen' to protect themselves from the harmful rays of the Sun

A sign that reminds everyone to ‘use plenty of sunscreen’ to protect themselves from the harmful rays of the Sun.  Source: Flickr commons. Image by Alex Liivet

 

 

Eating your mucous: a defence mechanism?

 

 

Mucous-ingestion:source flickr commons

Mucous-ingestion by this man, although disgusting,may actually be aiding his immune system. Image by imgarcade. Source: Google Image

 

 

As much as everyone would like to hide it, you have all picked your nose at one point or another in your life. And each time, you’ve probably been reminded of how disgusting and unhygienic the act is. Some people even take this behaviour to the next level, proceeding to ingest the hidden treasures. Could ingesting the contents of your nose actually be the opposite of what your mother has told you? Even, healthy?

Professor Napper at the University of Saskatchewan hypothesizes that eating the pathogen-containing mucous from the nose can actually produce an effect similar to that of a vaccine. The mucous and the hairs in the nose are a part of the innate immune response, which is essentially the first line of defence against invading pathogens. When you ingest the mucous, you’re ingesting all of these pathogens, some of which are potentially very dangerous if they enter into your bloodstream. Once ingested, these pathogens skip the bloodstream and make their way to the gastrointestinal tract where they teach our immune system to defend, such as a vaccine would. Professor Napper’s work is still in the beginning stages and no formal study has been conducted.

S.aureus, common pathogen in nose: source Google commons

S.aureus is a common pathogen in the nose that may be ingested and induce an immune response. Raeky. Source: Wikipedia

On the other hand, Dr Bischinger’s work, which is summarized in this article , describes the mechanism with which the immune system is boosted. He believed that  the pathogens that you introduce from the nose to the body, similar to those of vaccines, are already weakened. He suggested that there are bacteria-killing properties in the mucous of the nose that kill and weaken most of the bacteria, allowing it to be easily contained by our immune system. This mechanism  produces antibodies that our body desperately needs when the full-strength pathogens enter the body.

Moreover, parallels could be drawn from this to that of mothers who kiss their babies in the hopes of boosting their child’s immune system.  In the same way, pathogens that the baby is exposed to are weakened by the mother and then passed on to the baby, producing long-lasting immunity.

Mother kissing the baby: source Google commons

Mother kissing the baby in the hopes that she can provide the baby with weakened pathogens that can be more easily handled by the baby’s weak immune system. Image by Vera Kratochvil. Source Google Image

In conclusion, although pending actual scientific studies, I think that this just might be the natural immunity boost that we all need. However, I don’t think we are ready as a society to start picking away at our noses whenever we please!

 

-Gurtaj Mahil