Cholesterol’s role in heart disease

Posted on February 25, 2013 by | 2 comments
Causes of death pie chart (Image from http://www.sca-aware.org)

Causes of death pie chart (Image from http://www.sca-aware.org)

 

Heart disease is the leading cause of death in the world, and it has been long known that heart disease is highly associated with elevated levels of cholesterol.  Cholesterol is fatty substance which originates from dietary intake and liver production.  If you have thought of cholesterol merely as a measurement of obesity (which is not entirely wrong), you should keep in mind that an adequate level of cholesterol is vital to help your brain, skin, heart, and other organs grow and do their jobs in the body.

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Cholesterol can be divided into two groups: LDL (low density lipoprotein) and HDL (high density lipoprotein).  LDL is called “bad” cholesterol, because it is the LDL cholesterol that forms plaques and is associated with heart disease.  HDL is called the “good” cholesterol, because HDL cholesterol actually extracts LDL cholesterol from artery walls and moves them back into liver, preventing atherosclerosis.

HDL vs LDL (image from http://www.ellies-whole-grains.com/)

HDL vs LDL (image from http://www.ellies-whole-grains.com/)

 

The LDL cholesterol is unarguably one of the risk factors that often make heart diseases deadly, but it has not been clearly understood why. However, University of British Columbia researchers David Fedida and Jodene Eldstrom discovered that cholesterol disrupts the flow of the electrical currents that generate the heart beat, causing cardiac arrhythmias (irregular heartbeats).

 

We have countless ion channels present in the membranes of all cells in the body, and they are key components in a wide variety of biological processes. The type of protein channels that are involved in the mechanism by which the heart’s electrical activity occurs is voltage-gated Kv1.5 potassium channel.

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The heart undergoes depolarization (positively charged) as positively charged potassium ions move into the cell through Kv1.5 potassium channel. Shortly after depolarization, the heart releases potassium ions and returns its membrane potential to a negative value (repolarization).  The ion exchanges are regulated by Kv1.5 potassium channel.   The continuous depolarization and repolarization create small electric current.

All the cells with Kv1.5 potassium channel contributes to this process like little batteries, and the generated electricity flows through the heart as an impulse and the heart beats.  One important thing about this ion channels is that they are synthesized inside the cell and transported to the cell’s surface. They stay at the surface for only a few hours, and then they internalize back into the cells to be degraded or remade again.  Dr. David Fedida found that cholesterol disrupts this whole recycling process and affects the number of cells that can act as “little batteries”, causing the heartbeat to quicken, and eventually fail.  David Fedida explains that cholesterol-lowering drugs may help normalize the heart’s electrical activity.

Arrythmia

Small amount of cholesterol is inevitable for normal function of body. However, excessive cholesterol can lead to sudden cardiac arrest: the number one cause of death in the world.  This discovery of additional danger of cholesterol on coronary heart disease sheds light on sudden death in people with high cholesterol and opens ways to potential anti-arrhythmic drugs.

Andy Byun

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The Large Hadron Collider – advancing our knowledge or our doomsday?

Posted on February 25, 2013 by | 1 comment

The Large Hadron Collider is the largest man-made high-energy particle accelerator, which aims to allow scientists to test theories of particle physics. Through the collider, Physicists hope to find answers to some of the world’s still unsolved mysteries, such as the existence of the Higgs boson, a.k.a the God’s particle. Ultimately, it would advance our knowledge about the universe that we live in, and address the questions as to how it all began. However, some people has raised concerns as to the safety of the collider, due to the nature of the amount of  energy involved in the experiments and of the many laws of physics still unknown to us. There is even a website called Has The Large Hadron Collider Destroyed the World Yet, signifying the existence of large amount of concerns from members of the scientific community and the general public.

The Large Hadron Collider lies in a tunnel 175 metres beneath the border of France and Switzerland near Geneve, Switzerland

Opposition of the large hadron collider has proposed two such “ways” the world as we know it will end because of the Large Hadron Collider:

Micro black holes

Although the theory of the large hadron collider would ultimately reach energies high enough to create black holes has been disproved by the Standard Model of particle physics, some extensions of the Standard Model do however predicts the possible existence of micro black holes during the operation of the collider. Unlike the widely known black holes, micro black holes loses mass quickly than it gains, and eventually dissipates and vanishes. Therefore they are deemed harmless by most theories of physics now known to man.

Strangelets

A Strangelet is a hypothetical particle that consists of equal number of up, down and strange quarks, the elementary particles that form matters. Physicists predict the creation of such particle would results in a fusion process in which all nuclei that form all matter in a planet would be converted to strange matters. However, currently models suggest that strangelets, even if they can be produced, are short-lived and unstable under low temperatures, where the collision occurs in energies higher than the stable environment in orders of magnitudes.

Current theories have predicted the probability of a catastrophic event happening because of the collider is virtually none. However, if you are one of the people that lose sleep thinking about possibility of the end of world, you can rest assured until the year 2015, because during which the Large Hadron Collider has been shut down for upgrades since the end of 2012.

Jonathan Lui

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How Observant Are You?

Posted on February 25, 2013 by | 4 comments

In order to answer this question, watch the video below:

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When I did the experiment, I counted 14 passes and I noticed the gorilla. I found the gorilla distracting so my attention immediately went to it. Did anyone not see the gorilla?

After having watched the video, I found the study that went along with it and was actually quite intrigued by their results.

The paper started off by defining two key terms: change blindness and inattentional blindness.

Change blindness occurs when a person doesn’t notice large changes to objects or scenes, particularly if those changes are not the main focus of that scene.

Inattentional blindess occurs when a person is not paying enough attention and as a result misses seeing a whole object. The visual input is there but the person does not perceive the object and as a result that visual information does not get stored in their memory.

Inattentional blindness was the focus of the study mentioned above.

The 192 participants were each shown a video, 75 seconds in duration. In the video there were two teams composed of three players. One team wore black shirts and the other team wore white shirts. Each team was passing around a basketball. After about 45 seconds into the video, an unexpected event would occur. The video above is a copy of one of the videos participants were shown.

In total there were four different types of videos, and each participant was shown just one type.

Below is a picture of the four types of videos:

I seem to be very unlucky with technology….

The “Add Media” button refuses to work so I can’t upload a picture. For all those that are interested, you can find it in the paper. Up above, I made the word “study” a link to the paper. If you press on it, it will take you to the paper and to the picture 🙂

The picture in words:

Type 1 = transparent/gorilla

Type 2 = transparent/woman with umbrella

Type 3 = opaque/gorilla

Type 4 = opaque/woman with umbrella

  •     Transparent conditions mean that the black team, the white team,  and the unexpected event were all filmed separately and then superimposed through video editing
  •    Opaque conditions mean that everything was filmed live/simultaneously

To further complicate things, some participants were given an EASY task and told to only count the total number of passes made by the team they were observing. Others were given a HARD task and had to keep two counts in their head: one for number of bounce passes made and one for number of air passes made by the team they were observing.

RESULTS:

(1) In general, regardless of the video type or task given, 54% of all participants noticed the unexpected event and 46% did not.

(2) Lots of participants noticed the unexpected event during the easy task (64%) but much less noticed during the hard task (45%).

(3) In opaque conditions, 67% noticed the unexpected event, while in transparent conditions only 42% did.

Result (3) makes sense because in the transparent condition the video is much fainter and everything seems to overlap. This probably made it harder for the participants to distinguish between the players and any new stimuli (gorilla/woman with umbrella). Result (2) suggests that the more difficult the task, the more focused the observer, and the less likely they will be paying attention to/percieving anything in the surrounding environment. This seems logical as it often happens to me when I get very absorbed in a book that I am reading or task that I am completing. What surprised me most was that in general just about half of all observers missed seeing the unexpected event (Result (1)). To me, the gorilla was really obvious, but I also didn’t count the correct number of passes so it is possible I wasn’t focused enough.

Dragana Savic

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An Antidote For Alcohol?

Posted on February 25, 2013 by | 3 comments

I’m sure at one point or another, most people have gone out to a bar or a house party, lost track of time and realized “Shoot, my 8am class starts in a couple hours” or “I’ll get fired if I show up to work with a hangover again”. Wouldn’t it be nice if you could just take a pill and sober up almost immediately and hangover free?

A variety of oriental raisin tree has been the basis of a hangover cure for 500 years. Scientists have recently extracted a chemical from this tree called dihydromyricetin (DHM) which was tested on drunken rats with interesting results. The lead researcher, Jin Liang, claims “DHM will reduce the degree of drunkenness for the amount of alcohol drunk and will definitely reduce the hangover symptoms, in time it will reduce [an alcoholic’s] desire for alcohol”.

The effects of DHM have yet to be tested on humans, but when tested on rats, there were positive results. Liang found that a dose of DHM helped an intoxicated rat’s coordination return over 10 times faster than without it. When the rats had hangovers induced by alcohol injections, they were found to hide in the corners or a maze. Within minutes of being given a dose of DHM the rats were curiously exploring the maze as if they never had a hangover.

drinkingrats

Photo Source: beachpackagingdesign.com

With a pill that causes sobriety, it is logical that alcoholics are a target audience for this drug. Over a span of three months, rats were injected with alcohol and were given a choice between sweetened water or a sweetened alcohol solution. At the end of this period, it was noted that the rats treated with DHM drank 75% less of the alcohol solution than the rats without treatment did.

This chemical seems to be the cure for drunkenness, hangovers and alcoholism, but it isn’t the first alcohol antidote that has been discovered. Several years ago a similar compound called Ro15-4513 was created. Many believed this was the cure for alcoholism, but complications including a short half life (meaning many doses would be required for complete sobriety) as well as negative side effects in the case of an overdose, caused the development of Ro15-4513 to be deserted.

As useful as this drug would be to use from time to time, there would still be legal issues for some uses of it as DHM blocks the effects of alcohol but it would still remain in your bloodstream. Would you trust someone to drive a car after taking DHM? They would be acting sober, but what if the effects of DHM run out before the alcohol has left their body? I believe that if patented, this drug should only be available for use of alcoholics to cure their addiction otherwise it could lead to increased drinking and dependence on DHM.

Kathleen Leask

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New Device Makes Cancer Detection Easier!

Posted on February 25, 2013 by | 2 comments

One of the most feared diseases in the world is cancer. This deadly disease is predicted to occur in about 42% of all North Americans. The mechanism of cancer development starts with damage to a cell’s DNA causing it to grow and divide uncontrollably. Eventually, these cells drain other tissue of nutrients and change how our body functions, leading to serious illness and in most cases death. Despite all this, if cancer is detected early enough, a full recovery is possible. Traditionally, the problem with cancer has been that it is very hard to detect, and that when it is detected, it has already started to spread to other parts of body through the blood. However, researches at the University of California, Los Angeles (UCLA) have developed a device that can grab cancer cells from the blood.

Image shows a lab technician analyzing a blood sample. Image courtesy of nita lind

Image shows a lab technician analyzing a blood sample. Image courtesy of Flicr user: nita lind

Researchers are calling this new device the “NanoVelcro” chip. The way that this device works is that when blood is passed through the chip, small hairs coated with antibodies matching those of cancer cells trap cancer cells, allowing for them to be isolated and examined. The researchers reported that this new device was able to isolate single cancer cells in the blood. Dr. Tseng and his research team from UCLA believe that this device will help doctors analyze and determine the specific cancer a patient might have, the genetic characteristics of the person’s cancer, and the type of treatment that the patient should receive. Also, this new method of detecting cancer cells will help detect cancer much earlier, potentially saving millions of lives.

Oncologist providing radiation therapy to a cancer patient. Image provided by Flickr user: Tiptimes

Oncologist providing radiation therapy to a cancer patient. Image provided by Flickr user: Tipstimes

With this new advancement, we will be better able to detect cancer cells in the blood and prevent them from spreading to other organs in the body, which has been a major problem in the treatment of cancer. Also, by taking blood samples throughout the treatment of a cancer patient, doctors will be able to more accurately determine drug resistance and change treatment accordingly.

Below is a short video explaining how cancer spreads through the body, and the major problems with early detection.

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So, with new technology and advancements, it is becoming easier and easier to detect and treat cancer. This new device will help treat millions of people and save their lives. This is a major break through considering the fact that so many people either develop or are directly affected by this disease.

– Gagandeep Gill

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Will we ever leave our Solar System?

Posted on February 11, 2013 by | 3 comments

“Space: The final frontier” – Capt. T. James Kirk

August 05, 2012  10:36am PDT

This day is not one that jumps out in the mind of the average person,  but for those that remember, it marked an astounding moment in the history of the National Aeronautics and Space Administration, better known as NASA; on this day, at this time, the wheels of the rover Curiosity, touched down safely on the surface of Mars.

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Though only the most recent of a handful of rovers humanity has already deposited on the surface of the Red Planet, Curiosity signifies a strengthening of our space-faring prowess, allowing mankind to look to the stars and truly entertain the notion: “We can go further.”

So how far have we gone?

In terms of manned missions, the furthest we have achieved is the Moon landings, the last of which occurred in December, 1972. Our unmanned endeavors have traveled further, since there is no need for pesky hindrances such as life support.

In 1977, the space probe Voyager 1 was launched. Its mission: to explore our  outer solar system. Travelling at a breakneck speed of 61,500 km/h, it has taken the small probe 35 years to reach the outer edge of our Solar system,  cementing it as the furthest man-made object from the Earth. NASA predicts the probe will reach the outer edge of the solar system sometime between 2013 and 2015.

NASA Artist concept of Voyager 1
(Source: NAACL.blogspot.ca)

 Can we go further?

Since we have reached the edge of our solar system, is it possible to reach and explore other solar systems in our galaxy?  Our Milky Way is comprised of billions of stars, out of which millions contain orbiting planets. So it seems feasible that we posses the means to reach these neighboring galaxies and extend our interstellar presence.

Not so fast, there is no doubt that the Voyager is travelling very fast, in fact, it is currently the fastest interstellar spacecraft in existence. But despite this incredible speed, fast enough to circumnavigate the globe 5 times in an hour, it might as well be travelling at a snail’s pace relative to the enormous interstellar distances between solar systems.

Distance between interstellar bodies is measured in Light Years, and the closest solar system to ours, Proxima Centauri  is 4.22 Light Years away. At Voyager’s current speed, it would take approximately 75,000 years for the probe to reach the solar system!

What does this mean?

Even as we advance to  where we can safely land rovers on Mars, and explore the outer reaches of our solar system, we still do not posses the means to conquer the massive distances between us and our interstellar neighbors  Still, NASA shows no signs of slowing down.

And trust me, there is plenty to do in our home solar system.

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The Ethics of Organic

Posted on February 11, 2013 by | 1 comment

For millenniums, humans have survived off of natural sources of food, whether it came from hunting and gathering, or grown agriculturally like wheat and corn. But with a never-ending shortage and demand for food due to population growth, new agricultural solutions from man-made fertilizers to genetically modified organisms (GMOs) have become essential to our survival. The question of whether organic-grown food is the healthiest choice nutritionally has been a tough, if not controversial battle.

But what is organic?

The defnition of an organically-certified product differs between the laws of each country. In 1999, the United Kingdom Parliament defined organic farming as products which largely excluded growth hormones and feed additives, synthetic fertilizers and pesticides for livestock and farm-grown crops respectively. By 2005, in addition to the above definition, the United States’ Electronic Code of Federal Regulations added and classified GMOs to be non-organic, since they are not produced naturally.

Is organic healthier?

A 2006 review article states that there is a lack of data to suggest that our recent new conventions in agriculture affect the nutritional value in any significant way, arguing that organic foods are preferred due to ethical reasons rather than concerns for health. It was also noted that the most worrisome factors of recent agricultural changes would have to be the use of antibiotics in livestock, which has been linked to increase the growth of antibiotic-resistant bacteria.

Another study showed no nutritional difference between livestock that were fed GMOs rather than organic feed. The study also noted that conventional farming of GMOs often include the use of synthetic fertilizers and pesticides in agriculture, which have been proven to be safe as the compounds must undergo rigorous FDA-approval. If it is any consolation, we learned from the Chemistry 341 article at UBC that humans are exposed to 10,000 times more natural pesticides by weight than man-made ones.

Even with a lack of long-term studies on non-organic versus organic diets, these studies argue that there is no significant difference between the nutritrional value of two similar products. Nutrition is irrelevant to whether they were organically or non-organically produced.

Then why should I eat organic?

It was previously hinted that although organic food may not be healthier, it is often chosen over alternatives because of ethical reasons. New York Times food columnist, Mark Bittman, looks into not what, but how we are eating wrong in the following Ted talk:

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And the debate of organics still rages on today, and new evidence being found for both sides. There are many good ethical reasons behind organic food production, but conventionally grown products are important too, because if we can genetically modify plants to increase agriculture production, why wouldn’t we do so to feed those who need it? Ultimately I can see an importance to both of them, and for me, the bottom line is that non-organically grown fruits and vegetables are still safe to eat and buy against popular belief, but I will think twice now before choosing cheaper meats than those that are organically certified.

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