Tag Archives: research

A Potential New Class of Insect Repellents Using Catnip!

Posted on March 22, 2021 by | 2 comments

Although catnip is often used as a special treat for cats due to its euphoric and hallucinogenic effects, it has quietly been known as a powerful insect repellant. This strong reaction towards insects has led to scientists considering catnip as a potential replacement for currently available insect repellents.

However, up until now, it was not understood how exactly catnip repels insects. A recent study performed by Dr. Nadia Melo and her research team provides the necessary context to show how exactly one of the main chemicals in catnip, nepetalactone, can be used to create the next class of insect repellents!

Insect repellents are used to fend off insects such as this mosquito, which can spread disease through its bite.

Source: Unsplash.com/ekamelev

What’s wrong with current insect repellents?

DEET and permethrin are currently the two most commonly used chemicals in insect repellents. These chemicals get the job done, but they do have their downsides.

Firstly, certain mosquito species are developing resistance (ability to withstand effects) to insect repellents containing these chemicals according to a study performed by Dr. Deletre’s research team. This is very concerning as it is important for insect repellents to be effective at stopping mosquitoes because they are prominent spreaders of diseases such as malaria.

This short video by MalariaGEN does a great job explaining what resistance is in further detail and talks about how insecticide resistance occurs.

Video Source: MalariaGEN | Youtube

Furthermore, insect repellents with DEET and permethrin have their dangers, as they can potentially have toxic effects in adults based on reactions that some people have had. 

Keeping these reasons in mind, it is clear that there is a growing need for a better insect repellent than the current insect repellents on the market.

This is where catnip comes into play.

What makes catnip a good insect repellent?

Catnip contains a chemical called nepetalactone that is able to repel certain insects including mosquitoes. Research has shown that nepetalactone has similar effectiveness to DEET, indicating that it can be a good replacement for current insect repellents. Furthermore, nepetalactone has shown that it is non-toxic to humans based on the many interactions that humans have had with catnip.

How it works:

Dr. Nadia Melo and her research team were able to determine exactly how nepetalactone causes a strong reaction in insects. They found that nepetalactone was able to activate a pain receptor called TRPA1 in insects, which caused a strong irritating response in the insect’s body. In other words, nepetalactone turned on a switch in the insects that resulted in them experiencing pain. 

Scientists have stated that the way this chemical irritates insects is more complicated than the way that DEET and permethrin repel insects. Thus, they have suggested that mosquitos and other insects are less likely to obtain resistance to nepetalactone. 

Future of Nepetalactone:

The doors are now open for a new generation of insect repellents based on catnip. 

The use of nepetalactone to make new insect repellents can potentially replace current insect repellents containing DEET such as the one shown here.

Source: flickr.com/skiarc

Nevertheless, there is still work to do. Future studies are now looking into whether nepetalactone can be modified to trigger an even stronger reaction in insects. Furthermore, they are looking into exactly which species of insects that this insect repellent will work for.

-Karnvir Dhillon

 

 

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Mice Grown In Vials: Are Humans Next?

Posted on March 22, 2021 by | 4 comments

For at least a hundred years, researchers have been struggling to answer one question: how does a single cell become a full grown human.

One major barrier to fully understanding this process, was that we could never see it happening before our own eyes. Luckily, a team of biologists led by Dr. Jacob Hanna at the Weizmann Institute of Science had a major breakthrough: mice grown in vials. 

The Problem

In an interview with the New York Times, biologist Dr. Paul Tesar said:

“The holy grail of developmental biology is to understand how a single cell, a fertilized egg, can make all of the specific cell types in the human body and grow into 40 trillion cells. Since the beginning of time, researchers have been trying to develop ways to answer this question.”

Each one of us started the same, as just one cell. In our mothers, one cell became two, then four, which eventually led to us. During these beginning stages of development, we were what researchers call an embryo, or an early-stage animal. Embryos are located in a mother’s uterus, which acts like a house that provides everything needed to grow. 

To see what is going on inside this house, researchers have tried many different tricks including taking pictures, or even removing the uterus fully from animals such as mice to get a better look. What researchers have not been able to do thus far, is watch the embryo grow continuously outside of the mother. This has not only made research in the field difficult, but has restricted the work being done.

The Solution

Although the researchers at Weizmann were not the first to come up with the idea, up until now, mice grown outside of a mother have either not been able to survive, or did not grow correctly. In fact, it took Dr. Hanna and his colleagues 7 years to perfect their technique. 

The entire process consists of two steps. First, the uterus of a recently pregnant mouse is removed. Second, the uterus is transferred to a vial filled with liquid containing all the food it will need. As seen in the video below, the embryo is slowly spun to make sure it does not attach itself to the wall of the vial as that could result in death. 

Mice embryos growing inside spinning vials (Video from MIT Technology Review)

The mice were under constant observation and images, as seen below, were taken and compared to mice developing inside a mother. The two were identical. 

Mice developing over a 5-day period (Image from The New York Times)

Implications

As a result of this breakthrough, researchers will be able to better understand events including birth defects and miscarriages. Additionally, researchers can now easily change the environment that the embryo grows in to see what conditions can affect development. Although it may still be some time until this research is transferred to humans, this breakthrough certainly marks a big step in the right direction.

-Jessica Petrochuk

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Need to Sober Up? Just Breathe Out the Booze!

Posted on March 15, 2021 by | Leave a comment

With regards to alcohol, many of us have previously reached the so-called point of no return: a moment where the pleasant buzz is replaced by a throbbing headache (and massive amounts of regret). If only there was a simple way to quickly sober up…

Alcohol! Source: awee_19, Flickr

A simple overview of ethanol breakdown

First, let’s dive into how our bodies break down alcohol. Once ethanol arrives at the stomach and intestines, it is absorbed into the bloodstream. From there, most of the alcohol ends up in the liver. The liver is responsible for detoxifying 90% of the ethanol that we consume; the remaining 10% is eliminated through sweat, urine, and breath.

However, the rate at which the liver breaks down ethanol is zeroth-order: meaning that the breakdown rate is always constant, no matter how much ethanol is in your system. This explains why we haven’t been able to develop techniques to speed up the rate of ethanol breakdown in our livers.

Naturally, the next step would be to see whether we can speed up the elimination of the remaining 10% of ethanol in our bloodstreams. Turns out, we can! Remember how we said that some ethanol is breathed out? This works the same way that we exhale carbon dioxide: diffusion! Since the ethanol concentration in our bloodstream is higher than in the air that we breathe in, some ethanol diffuses into our lungs and we breathe it out!

Diffusion Explained.
Source: Free Animated Education, YouTube

A breathalyzer uses the fact that we breathe out ethanol to determine our blood alcohol concentration (BAC). Source: Dave Shea, Flickr

So can I just hyperventilate until I start to feel sober?

In theory, you could… but you really shouldn’t. Hyperventilating will reduce your ethanol levels, sure, but it will also decrease your CO2 levels: causing your brain’s blood vessels to narrow, and ultimately depriving your brain of oxygen. Thankfully, a recent study has found a simple and effective solution, utilizing isocapnic hyperpnea.

Isocapnic hyperpnea: what is it?

To put it simply, isocapnic hyperpnea (IH) is when you deeply (sometimes rapidly) breathe in air that has an equal concentration of carbon dioxide as in your bloodstream. This lets you breathe out all the nasty ethanol, while your CO2 levels stay steady. In the study, participants drank vodka, then were connected to a device which supplied air which had a CO2 concentration similar to what would be found in normal blood vessels. The results of the study showed that the participants who underwent IH were able to get ethanol out of their system more than three times faster than participants who breathed regular air!

A demonstration of the IH apparatus. Source: UHN

This technology could be widely available in the near future, since IH has already been approved as a treatment for clearing our bodies of other chemicals. IH could help paramedics in clearing the alcohol out of a patient’s system in a timely manner, which could ultimately save their lives. Remember to always drink responsibly!

 

– Sam Jung

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Treating Depression: Personalized Deep Brain Stimulation

Posted on March 15, 2021 by | 4 comments

How would you feel if the treatment or medication you were taking had little to no effect in suppressing your symptoms? Unfortunately, this is the case for 1 in 3 patients diagnosed with depression. These patients fall under a category known as treatment-resistant depression. Personalized deep brain stimulation, a promising alternative to conventional treatments, has the potential to treat various forms of depression by allowing physicians to tailor treatment to an individual.

THE PROBLEM

Depression, which is characterized by low mood, is linked to an imbalance of serotonin, norepinephrine, and dopamine neurotransmitters in the brain. It is a common mental illness that affects the way someone feels, thinks, and acts. However, it is important to note that depression varies significantly among individuals and many other factors play a role.

Source: flickr.com

As stated by Ben Paul from USC Viterbi School of Engineering,

“Mental disorders can manifest differently in each patient’s brain.”

There is no single treatment that can effectively treat the symptoms of depression among all diagnosed individuals. This makes it hard for physicians to provide the best treatment for their patients.

WHAT IS DEEP BRAIN STIMULATION?

Deep brain stimulation (DBS) is a surgical procedure where electrodes are implanted within specific areas of the brain. By electrically stimulating these parts of the brain, physicians can reduce the symptoms associated with depression. The amount of stimulation is controlled by a pacemaker that is placed under the skin on the chest.

The video below explains this procedure further and contains an interview with Edi Guyton, a patient who had this surgery: 

Source: CNN | Youtube

PROMISING ALTERNATIVE: PERSONALIZED DEEP BRAIN STIMULATION 

Even with deep brain stimulation, each patient’s response to treatment will be different. However, one of the pros of deep brain stimulation is that it results in immediate changes. This is the key component that allows physicians to personalize treatment. A 2021 research study led by Dr. Maryam Shanechi and her team at the USC Viterbi School of Engineering explains an approach that can be used to predict and see how an individual’s brain responds to stimulation. Her research will allow physicians to monitor brain regions in real-time.

How is this done? 

       Two tools have been designed: 

  1. Electrical stimulation wave to map brain activity
  2. Machine-learning techniques that can learn the mapped brain activity which is collected during stimulation 

The stimulation wave tool randomly changes the characteristics (amplitude and frequency) of the electrical impulse over time. A change in these characteristics is the equivalent of changing the dosage of a medication. Analysis of brain activity during these changes will help physicians determine the correct stimulation doses. 

THE FUTURE: TREATING DEPRESSION

Dr. Maryam Shanechi’s research will allow physicians to personalize deep brain stimulation for all patients diagnosed with depression. This can help physicians overcome the difficulty of assisting individuals with treatment-resistant depression. Success within this field of personalized deep brain stimulation not only holds great potential for treating depression but can also lead to improved treatments for other psychiatric disorders. 

Source: flickr.com

 

– Samantha Nalliah

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Microalgae Used to Create Biodiesel: An Organism That Can Save Our Planet?

Posted on March 11, 2021 by | 1 comment

As time continues to move forward, global climate change is becoming an ever-growing issue. In order to mitigate the effects of global warming, we as a society need to change our ways of living. Due to rapid industrialization and urbanization, there is an increased amount of pollutants emitted into the atmosphere that are slowly damaging the earth. In today’s world, most of the energy production is coming from fossil fuel burning, which is the key source of carbon dioxide (CO2) emissions to the atmosphere. Energy demand will continue to increase and as of right now, fossil fuels still contribute to 82% of the global demand. The figure below displays gas emissions from various modes of transportation.

Source: bbc.com

An article written in 2020, by Ashokkumar Veeramuthu and team, describes the potential use of microalgae to produce biodiesel. You may be asking, what are microalgae and what the heck is biodiesel? Let’s jump straight into it.

What is Biodiesel?

Biodiesel is made from materials such as plant oils. It’s an alternative to petroleum diesel and emits much less harmful substances into the atmosphere. Since we are slowly killing our planet, replacing our non-renewable energy sources with green alternative sources doesn’t sound like a bad idea.

Why use Microalgae?

You may be wondering, what is so special about microalgae? Why can’t we use some type of terrestrial plant like corn to produce biodiesel? Studies show that the use of microalgae is the best option for the production of a renewable and sustainable source of energy. Microalgae are photosynthetic organisms living in wet environments that can convert sunlight, water and CO2 into biofuel. There has been a shift of attention towards microalgae to produce biodiesel because microalgae provide many advantages over terrestrial plants. The benefits of microalgae include high lipid concentrations (which can easily be converted to biodiesel through a process called transesterification), rapid growth and minimal nutrient requirements. The table below compares values of the biodiesel productivity of microalgae and other plants.

Biodiesel productivity of different feedstocks. Source: intechopen.com

Microalgae also tend to grow 10x more rapidly than terrestrial plants and less than 10% of the land is required to produce the same amount of biomass. Additionally, microalgae don’t require large amounts of fertilizers to grow, unlike terrestrial plants. The cultivation of microalgae can be carried out by using wastewater, since it is rich in key nutrients. Furthermore, the use of wastewater decreases costs greatly and makes biodiesel production commercially viable.

This video showcases the general process of biodiesel production in a nutshell:

Source: David T. Kearns (YouTube)

In today’s world, there’s a shift of attention to deal with the issue of climate change. From Elon Musk creating fully electric vehicles to Joe Biden rejoining the Paris climate accord within hours into presidency, we as humans are finally taking initiative to save our planet. The future of creating fuels from microalgae sounds promising and having a range of renewable sources of green energy will be beneficial to us in the coming time.

– Parwaz Gill

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“A drink a day keeps reality at bay”: Atrial Fibrillation

Posted on March 8, 2021 by | Leave a comment

This happens quite often: people come home after a long, tiring day and look forward to cracking open a beer, making a cocktail or pouring themselves a glass of wine. Sure, this may be an evening ritual for many, but at what cost? A recent study led by consultant cardiologist, Professor Renate Schnabel, at the University Heart and Vascular Center determined that people who regularly enjoy small amounts of alcohol develop an increased risk of atrial fibrillation (AF).

What is atrial fibrillation?

Atrial fibrillation is when a person has an abnormal heartbeat rhythm. The two upper chambers, the atria of the heart, beat out of sync from the two lower chambers, the ventricles. Since the upper and lower chambers of the heart are not working together, the lower chambers may not be able to pump enough blood to our lungs and throughout our body. Due to this, people with AF may feel tired, dizzy or suffer from chest pains. The irregular heart rhythm may also cause blood to pool in the heart which can cause clot formation and thus lead to strokes or heart failure.

Atrial Fibrillation vs. Normal Sinus Rhythm on Electrocardiogram. Source: Clearvue Health

Ingesting large amounts of alcohol, binge drinking for example, has been one of the leading risk factors that may result in AF. Until now, however, there has not been enough proof linking the effect of drinking small amounts of alcohol to AF. This is why the current study led by Professor Renate Schnabel has been an important step in AF research.

The video below called “What is Atrial Fibrillation”, created by the Youtube channel known as British Heart Foundation, gives an overview on what AF is:

Linking atrial fibrillation to alcohol consumption 

Past research, such as the study conducted by Andriy V. Samokhvalov and his colleagues, found a link between alcohol consumption and the development of AF. However, a limitation from this study was that it did not clearly prove the association between light drinking causing AF.

In the study conducted by Professor Renate Schnabel, participants were given medical examinations and were asked to share how often they consumed alcohol as well as their drinking pattern. During the follow-up with the study participants, which occurred after approximately 14 years, they were analyzed for any link between their alcohol consumption and AF. Researchers discovered such a link even for individuals consuming low amounts of alcohol. In fact, 5854 people ended up developing atrial fibrillation after 14 years. 

What this means for alcohol drinkers 

Even low amounts of alcohol consumption can lead to AF which is a stepping stone for other problems such as heart failure and strokes. This is why it is important to get checked for AF even if symptoms are minor (ie. heart palpitations, dizziness, chest pains, etc.). Also, proper management of drinking habits may lower the risk of developing AF. After all, protecting your heart will only benefit you in the long run.

– Ramdeep Dosanjh

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