Tag Archives: health effects

An Unlikely Hero

Posted on March 19, 2018 by | 1 comment

Conservation has entered the spotlight in recent years, but there is one resource shortage no amount of recycling can help: human organs. Every day 2o people die waiting for an organ transplant and this problem is only getting worse. From 1991 to 2015, the number of people on the transplant list in the US has risen by nearly 100, 000, while the number of donors has risen by less than 10, 000. This problem is exasperated as only 3 out of every 1000 deaths leave organs viable for transplant. Luckily Biologist Luhan Yang may have a solution with an unlikely face.

Source: Google

Yang literally hopes to bioengineer pigs into human organ farms. Yes, organ farms. Although it sounds crazy, xenotransplantation, the transplant of animal tissues/organs into people, is not a new concept. Pig and cow heart valves have been transplanted into humans as an alternative to mechanical valves for almost 50 years. But implanting a functional organ is very different than implanting a simple valve. 

Source: Flickr Commons

Pig and cow heart valves are treated with a variety of chemicals to preserve the tissue and prevent it from rejection by the immune system. Since the tissue is only preserved, it is not technically alive, which obviously would not work with an organ. To be of any use, an organ must be alive and fully connected to the rest of the body, which understandably presents some major problems.

The first problem is organ rejection. Everyone’s cells have protein “markers” displayed on their surface completely unique to the individual. Your immune system uses these to distinguish between what’s you and what isn’t, so it doesn’t accidentally attack itself. That’s why patients’ blood types AND protein types must match for a transplant to be successful. Even then, the recipient must spend the rest of their life taking anti-rejection medications. Even organs from close family members often don’t match well enough to risk the operation, so transplanting from an entirely different species is undoubtedly more difficult.

Source: Flickr Commons

The second problem is the potential spread of viruses. Pig and human anatomies share certain similarities, which makes them ideal to grow organs. But this means many of their diseases can also infect us, like the H1N1 swine flu outbreak in 2009. Specifically, the type of virus of concern is called an “endogenous retrovirus”. Retroviruses are a special type of virus able to open up an infected host’s DNA, and insert its own before repairing it. This means the virus is literally part of the pig’s genome, and therefore is exceptionally difficult to remove.

Source: Flickr Commons

This is where Yang comes in. She hopes to solve these issues by genetically modifying pigs using CRISPR/Cas9 technology. CRISPR is a revolutionary gene editing technique that  allows scientists to open organisms’ DNA up at specific locations to add or remove segments. In 2015, Yang’s team made history by successfully developing a method to remove 62 retroviruses from pig cells at once. It was the largest number of modifications ever done to a mammalian genome in one procedure. Then last year, her team produced 15 live piglets without any harmful retroviruses. Their next goal is to take CRISPR even further to produce what they call “Pig 2.0”. They hope to further modify pig’s DNA to make their organs more human-like, solving the problem of organ rejection.

1 Comment

Posted in Biological Sciences

Tagged ,

The Role of Vitamin D and the Deficiency of Vitamin D

Posted on February 5, 2018 by | 1 comment

Health issues are one of major concerns of us in present days. As our lives become urbanized and modernized, we take less care of our body. Subsequently, our nutrition balances are getting worse. Unfortunately, it is undeniable fact.

One of crucially important nutrition that we are usually missing these days is Vitamin D. Many of us may have heard about vitamin D at least once.

But, it is just without knowledge of its important role in our body when it is deficient.

Vitamin D, in simple description, is a key nutrition that regulates our feelings and health (preventing depression and strengthens bones). Therefore, it causes several problems without sufficient amount of vitamin D intake.

Vitamin D is synthesized in our cell tissues under the skin with exposure of sunlight, specifically ultraviolet rays:

  • In human, when 7-dehydrocholestrelol in our skin is exposed to sunlight, it is converted into cholecalciferol which is vitamin D3.
  • In plants, when sterol meets sunlight, it is converted into calciferol which is known as vitamin D2; regulates calcium and phosphorus in our body.

Source: wordpress vitaminsaandd

We are only able to treat vitamin D in form of D2 and D3 in our body and they both work the same thing during the metabolic process.

Vitamin D is easily absorbed through the skin into our body within the wavelength of 290 nm to 315 nm. People who spend more than 20 minutes a day outside between 10 am to 2 pm would have no worries of vitamin D deficiency.

However, due to the location of Canada (cloud-covered sunlight during winter in the norther hemisphere region) and long rainy seasons, we are not freely able to enjoy the sunlight well to absorb the enough amount of vitamin D.

So, vitamin D deficiency is very common to people in Canada during the winter season since we have much less exposure to sunlight.

source: nutritionaction

As a result, vitamin D deficiency may causes several serious problems:

1) Weaken the immune system

Vitamin D enhances T-cell; cells that destroy microbes causing diseases. In case of vitamin D deficiency, T-cell may be weakened.

2) Diabetes

Risk of type-2 diabetes increases by up to 80 % – Vitamin D helps with insulin (hormone that regulates blood sugar level) secretion and conversion to glucose (a type of sugar from food we eat) energy. Low levels increase insulin resistance and damage glucose metabolism

3) Cardiovascular diseases (hear and blood vessel diseases)

Vitamin D inhibits renin which is a hormone increases the blood pressure of the systolic period. Vitamin D deficiency increases risk of several cardiovascular diseases, including hypertension (high blood pressure), heart attacks, and heart failure.

4) Depression

Vitamin D deficiency causes low serotonin levels and high cortisol hormone. Cortisol is stress hormone and serotonin is brain hormone that regulates happiness. The level of serotonin is increased when the body is exposed to sunlight.

source: department of nutrition, Harvard school of Public Health

 

To prevent vitamin D deficiency, it is best to expose oneself to sunlight 15~20 minutes a day without sunscreen. When it is not possible to spend time under the sun, however, intake of vitamin D with foods are another good option.

 

source: asianetindia

 

Sources of vitamin D from foods:

  • salmon&tuna
  • whole grains
  • egg yolk
  • mushroom
  • milk
  • cheese

source: BC Medical Journal

 

Even we intake vitamin D with foods, the content is too small for suggested daily dose. Therefore, the intake of vitamin D supplements are considered as the second-best option. However, supplements may cause the overdose problem so that it is crucial to follow the recommended dosage.

 

YouTube Preview Image

 

1 Comment

Posted in Biological Sciences, Issues in Science

Tagged , , , , , , , ,

Here’s Why Coffee Is Good for Your Health

Posted on January 21, 2018 by | 1 comment

We all love our morning coffee. Photo courtesy of blogTO

Coffee has existed since approximately the 15th century – and over these years it has amassed a lot of confusion about its effect on your health.  The media has played a role in pushing a negative view towards the effects of coffee. Us coffee lovers have always had a family member or friend comment with an expression of concern regarding our love for coffee.  It’s about time coffee drinkers put an end to this narrative!

Well, if you are a huge coffee lover, you will be happy to know that scientists have discovered that there is no connection between coffee and an increased risk of cancer or heart disease. In fact, the Universities of Southampton and Edinburgh published a meta-analysis investigating the effects of coffee on health. Amazingly enough, the paper used an extensive sample size analyzing over 200 papers! They found that drinking three to four cups of coffee a day may actually improve your health. Furthermore, they concluded that those who drank coffee were 17% less likely to die an early death, 19% less likely to die of heart disease and 18% less likely to develop cancer, compared to people who did not drink coffee.

Courtesy of Harvard School of Public Health

How does coffee work? The active ingredient in coffee is caffeine. Caffeine stimulates your brain and increases your alertness. Coffee also contains a lot of antioxidants, which are molecules that prevent damage that can cause cancer. Reactive molecules called “free radicals” attack our body and damage cells. Antioxidants stabilizes the oxidants, thus stopping them from harming our body!

David Heber, director of Center of Human Nutrition, UCLA discusses the effects of coffee.

Okay, now we know coffee can be healthy, but we also know that too much of anything is bad. How much coffee is too much coffee? Health Canada recommends adults limit caffeine intake to no more than 400mg/day. This is approximately three 8-ounce cups of coffee. Surpassing these limits could result in increased heart rate, changes in sleep patterns, heartburn, and more.

Remember that it in order to maximize coffee’s health benefits, minimize the amount of cream and sugar you put in your coffee. Sugar can singlehandedly nullify the positive effects you would get from coffee.

Robert Poole, the lead author of this study, says that these findings are “reassuring for coffee drinkers, as long as they drink in moderation”. Future studies will ideally pinpoint which type of coffee beans will have the greatest health benefit.

By Misam Ibrahimi

1 Comment

Posted in Biological Sciences, Science in News

Tagged , , , , , , ,