Health

Bee Stings

Question:

Can repeated bee stings create a vitamin C deficiency in a beekeeper who works with many bees? If so: 1) how can the vitamin C deficiency be evaluated; and 2) how can he  make up for the vitamin C deficiency?

Answer:

I have not heard or cannot find anything in the literature that indicates bee stings can cause a vitamin C deficiency.  I have heard that taking large doses of vitamin C can relieve the severity of a bee sting.

- Robert Anderson

 


 

Fever

Question:

A boy who feels ill touches his forehead with his hand to see if he has a fever. Will he be able to tell? Yes or no, and why?

Answer:

This is an interesting question. What you are describing in this vignette is what we call a “tactile fever” meaning that when someone feels the forehead of another and notes that the person feels hot to the touch. Now this feeling of warmth really means that there is a differential in the temperature between the feeler’s hand and the person with the fever. However, this is not the only way that the forehead would feel warm relative to the hand. This could also occur when the person feeling the febrile patient (one with the fever) has a cool hand and is feeling a forehead that is normal temperature (but still warmer than his hand).

So in the vignette you describe in which a boy with fever feels his own forehead, all other things being equal his hand – being the same part of the body as his forehead – should feel the same temperature (i.e not warm, not cold). This may not actually occur because of the way a fever is created. Your temperature is controlled by a part of your brain known as the hypothalamus. When you have an infection (bacteria, virus or fungus) your hypothalamus raises your core body temperature in an effort to fight the infection. The raising of the temperature is facilitated by 1) raising your metabolic rate, thereby creating more heat and 2) by vasoconstricting (narrowing the blood vessels) in your periphery (i.e. arms and legs) in order to conserve the heat loss from these limbs. The result of this is that your core will be warm but your periphery will be cool and will make the boys hand cool while his forehead is hot. Thus a boy with fever may feel his own hot forehead.

 


 

Smoking

Question:

I’m 60 years old and have smoked a pack of cigarettes since I was 14. I’m in great health as attested to by almost monthly tests for the past 10 years. I have none of the symptoms people connect with smoking. I look younger than most people my age (I’ve just started getting grey hair this past year). I’m not coughing or hacking. My wife is a jogger and I used to go with her. I ran the distance with her but eventually stopped because she was too slow for me.  The only thing I can think of, and it may seem far-fetched, is that I immigrated to Canada from England. Everybody knows that the whole world outside North America smokes and they live longer than we do. If the above is pertinent, it leads to a follow up question: what are we doing wrong?

Answer:

In fact, the statistics are a little different than you suggest.

According to the World Health Organization’s latest report (http://www.who.int/tobacco/global_report/2011/en/index.html) smoking rates vary widely by country from (3% to 55%): in 2009. Canada is among countries with low daily smoking rates at 14% together with the United States and the United Kingdom at 16%.

According to the Organization for Economic Co-operation and Development, Canada is in the top 10 in the world in terms of life expectancy. The United Kingdom is currently in the top 20, and the United States is in 26th place. Therefore, Canadians born this year are expected to live longer than people born in most other countries. Research also shows that Canadian smokers have a life expectancy that is 7 (males) to 10 (females) years less than the population as a whole (Baliunas D, et al. Smoking-attributable mortality and expected years of life lost in Canada 2002: Conclusions for prevention and policy – available from Chronic Diseases in Canada, 2007;27(4):154-162.)

Even if individual differences in physical fitness, well-being and life expectancy among people can be explained by factors such as lifestyle (e.g., smoking), genetic factors or access to health care, it remains that each day, 100 Canadians die of a smoking-related illness such as cancers, cardiovascular diseases and respiratory diseases ( http://www.hc-sc.gc.ca/hc-ps/tobac-tabac/legislation/label-etiquette/mortal-eng.php). Thus, smoking is responsible for more deaths of Canadians than high blood pressure, being overweight or obese, or physically inactive.

For information and advice on quitting smoking, please visit Health Canada’s website at http://www.hc-sc.gc.ca/hc-ps/tobac-tabac/quit-cesser/index-eng.php

 


 

Disease

Question:

What is the most dangerous and spreadable disease?

Answer:

This is a great question. The answer depends on many things such as your age, where you live in the world, the activities you engage in every day, and whether or not you have received vaccinations for a particular disease. Spreadable diseases (otherwise known as communicable diseases) are contagious meaning that they are spread from person to person. Many of them are preventable through vaccines, hand washing, safe sex, not sharing an object (such as a glass) with a person who is sick, and adopting healthy behaviors to promote your immunity.

We have all probably had a communicable disease. For example, the cold or flu is a well-known communicable disease that can be spread through physical contact with a person who is infected. This contact may involve touching or kissing or through tiny droplets in the air when someone coughs or sneezes. Additionally, communicable diseases can be spread through sharing an object that an infected person has used; for example, meningitis can be spread when you share a drink, cigarette or toothbrush with someone who is infected or athelete’s foot can spread if you share a bathtub/shower with someone who is infected. Other common communicable diseases are sexually transmitted infections that can be spread through sexual contact with an infected person.

Overall, it is reported by the World Health Organization that the following spreadable diseases are responsible for 50% of all premature deaths globally:  pneumonia, tuberculosis, diarrhoeal disease, malaria, measles and HIV/AIDS. However, a large majority of these deaths occur in developing countries where vaccinations are not as common and effective treatments are often lacking. Furthermore, in developing countries, they are often dealing with issues related to unsafe drinking water and poor sanitation. Thus, your geographic location in the world is a major determinant of what diseases you are more at risk for and whether they are lethal.

In Canada, the statistics are quite different. According to Statistics Canada, the only communicable diseases that are identified in the top 10 causes of death for 2008 include pneumonia and influenza; it is reported that they account for just over 2% of all causes of death in Canada (5,386 people/year). Of course, cancer and heart disease are the top two causes of death and are responsible for many more deaths, but they are generally not communicable. It is important to note that the state of your health and your age has a lot to do with how you respond to communicable diseases such as pneumonia and influenza. Often those who die from pneumonia and influenza are the elderly and/or those with pre-existing illnesses. Additionally, the Association of Medical Microbiology and Infectious Disease indicates that one of the most lethal diseases is tuberculosis, only next to AIDS – both are communicable diseases. About 1/3 of the world’s population is infected with tuberculosis. In fact, tuberculosis is on the rise in Canada and throughout the world. However, the death rate is substantially less in Canada compared to diseases such as pneumonia and influenza. Although tuberculosis is a lethal disease, it is also treatable if diagnosed and if the treatments are available and adhered to and/or affordable where you live.

Communicable diseases are spreadable and can be dangerous. As the common saying goes, the best cure is prevention!

- Jennifer Lapum

 


 

Correlation between disorders

Question:

One hypothesis that recently blipped my radar is that there may be a link between autism, schizophrenia, OCD, and autoimmune disorders; they may all be differing expressions of a mother's infection with a harmless virus, deeply affecting the the development of the fetus before it can develop immunity. So, with that in mind, I have a couple questions: 1. I'm a pop sci nerd. I think I lifted this from a Discover mag. Is there any actual research that you're aware of that shows this to be a promising avenue, a dead end, or something else altogether? 2. If there is anything to this idea, one testable prediction we could make is that there ought to be a direct correlation between mental disorders, immunofunction disorders, and endocrinal disorders. Are you aware of any studies that have been/are being conducted along these lines? {Full disclosure: I'm an insulin-dependant diabetic; in the past year since diagnosis, I have (anecdotally) noticed a vast shift in a variety of mental functions, from mood to clarity to rationality. Enough so to be asking, at least!}

Answer:

While Autism, Schizophrenia, OCD and systemic autoimmune diseases are all distinct disorders, the common link between all these may be their multifactorial origin where genetic and environmental factors are involved.

As for Autism, the common popular concern has related to vaccination as possible environmental trigger, but no epidemiological evidence for a role of measles--‐mumps--‐rubella vaccine is available. Some studies suggest that primary trigger for autism may be gestational and early childhood vitamin D deficiency but it does not exclude genetic predisposition.

Schizophrenia is a complex disorder with multiple genetic and environmental factors. The congenital constitutional vulnerabilities involved in Schizophrenia include both inherited and acquired (prenatal events affecting fetal neurodevelopment and postnatal stressors such as brain trauma) factors. Similarly, systemic autoimmune disorders involve multiple genetic and environmental factors (e.g., viruses) that result in dysregulation of the immune function that manifests as pathological autoreactivity leading to autoimmune pathology. The OCD, a psychiatric disorder, is possibly triggered by genetic, neurological (brain abnormalities and decreased Serotonin levels) and environmental (infection) factors.

Hence, as for the first question, the infection by a virus could provide an environmental trigger in some autoimmune diseases but other kind of factors may operate in diseases like Autism, OCD and Schizophrenia. As for the second question, there exists a neuro--immuno-- endocrine axis within the body system that may influence a variety of immune--mediated diseases, metabolic and other disorders but the triggers and outcome are likely to be disease specific.

- Azad K. Kaushik

 


 

Energy Drinks

Question:

Do energy drinks really give you energy or do they just cause other health injuries?

Answer:

Energy drinks are beverages that contain caffeine, caloric or non-caloric sweeteners, and other ingredients including amino acids, vitamins, minerals, and herbs. These beverages should not be confused with sports drinks, which are commonly consumed to restore fluids and electrolytes after periods of prolonged or intense physical activity.

Although energy drinks may contain up to 110 kcal per cup, caffeine is the main component responsible for the stimulating effect of energy drinks.  Recently, the amount of caffeine in caffeinated energy drinks has been limited to no more than 180 mg per container. To put this in perspective, that is the equivalent of 1-2 cups of brewed coffee. Health Canada recommends healthy adults not exceed 400 mg of caffeine intake per day from all sources, while other experts suggest that it should be reduced to 200 mg per day. Excessive amounts of caffeine may cause insomnia, nervousness, restlessness, upset stomach, nausea, irregular heartbeat, and anxiety.

Energy drinks may also contain B-vitamins, mineral, amino acids, or herbs. While many of these components may seem harmless, in the case of the B-vitamins, for example, the levels contained in these drinks may greatly exceed the recommended levels. The effects of some of these other added ingredients have been investigated in research studies on various markers of health; however, often times the trials are of short duration or conducted in isolation of other energy drink components. Thus, it is unknown how these components affect your health over the long-term.  In addition, it is difficult to extrapolate the results to all consumers, including children and to those who may consume more than a few servings a day for prolonged periods.  More importantly, natural herbs and added ingredients in energy drinks may interact with certain medications or supplements. Be sure to check with your primary care physician before consuming these products if you are taking drugs or other supplements to avoid any ill health effects.

When consumed in moderation and within recommended limits, energy drinks pose no risk to healthy adults, but they should not be seen as contributing to a healthy diet. Energy drinks and caffeine are not required for achieving a healthy diet. Furthermore, energy drinks should never be used as a meal replacement, consumed for hydration following exercise, or mixed with alcohol. Energy drinks are also not recommended for pregnant or breastfeeding women, people who may be sensitive to the effects of caffeine, or for children and adolescents.

- Nick Bellissimo

 


 

Sources of vitamin D

Question:

What are good sources of vitamin D during the winter months?

Answer:

Vitamin D is often referred to as the “sunshine” vitamin since the skin is able to synthesize it with adequate sunlight exposure. However, due to the known association between sunlight exposure and skin cancer risk, many health agencies suggest using sunscreen on skin surfaces prior to venturing out into the summer sunlight. While this process may reduce the risk of developing some skin cancers, it also completely prevents the skin from making vitamin D. For those of us living in northern latitudes, vitamin D synthesis during the winter months is inadequate. For these reasons, dietary sources of vitamin D and vitamin supplements become increasingly important to maintain adequate vitamin D levels. The active form of vitamin D in the blood is 25-hydroxy vitamin D and we should maintain levels of ≥ 50 nmol/L.

Vitamin D is essential for helping the body absorb calcium for maintenance of strong bones and teeth, and protection against developing osteoporosis and various other bone diseases. Furthermore, there is emerging evidence that there are benefits of vitamin D intake in diabetes, heart disease and some cancers.

The Vitamin D requirement for most adults (1 to 70 years of age) is 600 IU/day) and 800 IU/day for everyone older. These recommendations are based on the assumption that we have minimal sunlight exposure. In addition, a daily vitamin D supplement of 400 IU is recommended for those over the age of 50.  You may require more than this so it is always best to check with your primary care physician or a registered dietician.

Although following Canada’s Food Guide is a great way to meet our nutrient needs, it can be more challenging to meet vitamin D requirements from food alone. In fact, the only natural food sources of vitamin D are egg yolks and fatty fish. Because of this, Canada fortifies many commonly consumed foods with vitamin D. These include cow’s milk and dairy products, some margarines, soy beverages and fruit juice.

- Nick Bellissimo

 


 

The brain's reward system

Question:

Why do humans’ minds make them do things that are not safe (drugs, unhealthy food, computer game obsession, etc.) although it’s not good for survival and survival is what all animals want?

Answer:

When a stimulus such as food or a potential mate is encountered, the ventral tegmental area of the brain increases dopamine in the nucleus accumbens. Both of these structures are located near the very centre of the brain. The release of dopamine reinforces the precipitating behaviour, making it more likely to be repeated in the future. Researchers believe that this is how several important behaviours for survival, including eating and reproduction, are learned.

But, you are asking about an apparent inconsistency: If the brain evolved to promote survival, how can it promote behaviours that contradict that imperative?

Whereas the brain’s reward system serves the sensible function of reinforcing survival related behaviours (i.e., feeding and reproduction), it can also be stimulated by survival irrelevant ones.  For example, Anne Blood and Robert Zatorre (2001) at McGill University used neuroimaging to show that music stimulates the very same reward circuit that eating and reproduction do (see also Koelsch, 2014). Based on those data, they argue that music listening is reinforced by the reward system in the same way as eating and reproduction. Although I am less familiar with work on video game obsession, researchers think that gaming stimulates the reward system to reinforce play.  You might think about video games as a way to artificially stimulate the brain’s reward system.

This brings us to the issue of drug use. Like music, food, and reproduction, many drugs of abuse (e.g., amphetamines and cocaine) stimulate the brain’s reward system, thereby promoting re-use, even in spite of associated risks to health and well-being. 

In summary, behaviours that stimulate the brain’s reward system lead to an abundance of dopamine in the nucleus accumbens, which promotes the repetition of the behaviour that stimulated the reward system in the first place.  Whereas you might pass judgement on the various ways of stimulating the reward system, the brain’s reward system takes a more neutral stance: stimulation is stimulation.

- Randall Jamieson

 


 

Diabetes

Question:

I have two questions regarding diabetes, since my friend was just diagnosed with type 1 a couple months ago. 1. What problems are created by using the lancet to collect blood (if there are any), especially in developing countries like Africa and India 2. Are there any technologies/research teams that have discovered a way to measure blood glucose levels without penetrating the skin to collect blood?

Answer:

1. The new technologies are very safe. In fact, the devices are single use, meaning that they are used just once, so the risks of infection due to multiple use are completely eliminated. These same devices contain a spring that push the needle in immediately after injection begins. Thus the risks of needlestick accident are again avoided. As well, the needles themselves have been shortened as much as possible (4 mm) to minimize penetration of the skin. You can reassure your friend that the use of test strips and a device to prick and sample blood for measuring blood sugar are very safe. Unfortunately, I am not up-to-date on technologies currently used in Africa and India.

2. There is still no technology available to the public that does not penetrate the skin to measure blood sugar or glycemia. The word says it all: gly- (glucose) and -cemia (referring to blood) or translated from the Greek glukus, meaning sweet, and haima, meaning blood. So a blood sample is needed to take the measurement. We might think of a technology such as the one for measuring oxygen saturation that uses wavelengths, but this is not applicable to blood sugar measurement. However, there are some technological breakthroughs that could soon change the picture. For example, contact lenses created by the Google X laboratory measures blood sugar in real time and sends out an alert in the event of high blood sugar! However, this technology has not yet entered the market, it is still an ambitious pilot project.

3. In Quebec, we have the Réseau de recherche en santé CardioMétabolique, Diabète et Obésité (CMDO, www.rrcmdo.ca) and in Canada, there is the Canadian Diabetes Association (www.diabetes.ca ) where you can follow the research on diabetes and ask all your questions. Don’t be shy!

- Lucien Junior Bergeron

 


 

Phytoandrogens

Question:

I live in Kelowna and I forage for some of my food. I like to stay healthy and exercise regularly. I avoid being exposed to xeno and phyto estrogens as much as possible as building muscle is the goal of my training and I would like to continue being a man, hahah. I am trying to increase my androgen levels whenever I can but I will only consider natural methods. I read numerous places that pine pollen contains a vast array of phytoandrogens as well as a host of other vitamins and minerals, amino acids, etc. Traditional Chinese and Ayurvedic medicine has apparently wielded pine pollen as a superfood and natural male enhancement for thousands of years. Stephen Harrod Buhner wrote a great book titled "The Natural Testosterone Plan for Sexual Health and energy" if you would like to check it out. My questions for you: Are phytoandrogens actually present in the pollen of the pine tree? If so, are they bioavailable when ingested orally? Also, if it is universally accepted that there is excess of xeno/phyto estrogens in our environment/diet, why is there such a lack of study into phytoandrogens?

Answer:

Phytoandrogens belong to a broad group of compounds called phytohormones. Just like the hormones in the human body, these chemicals are produced by plants and are responsible for regulating activities in the plant. These include processes like regulating sugar production through photosynthesis or developing seeds and pollen.

Phytoandrogens are similar in function to human hormones, called androgens. These are considered to be “male” sex hormones, though in reality both sexes produce androgens (though males typically produce more). Similarly, there are compounds called phytoestrogens which mimic the “female” hormone estrogen.

In terms of their impact on human biology, there have been a large number of studies aimed at understanding these compounds. A quick (and not exhaustive!) search in academic literature reveals over 1000 peer-reviewed publications on phytoestrogens. There is less research on phytoandrogens, but with careful searching there are some facts we can find.

To begin with, I’d like to address some information regarding phytoestrogens. To begin with, you aren’t in danger of “feminization” through dietary estrogen. In 2010, a study was published which examined the results from 15 different experimental outcomes looking at how phytoestrogens (specifically compounds called isoflavones) affected males. These studies all revealed in healthy men, there was no effect of phytoestrogens on male characteristics including sperm count or testosterone levels. In fact, many asian cultures have diets which contain much higher levels of isoflavones than are typical in North America through a diet rich in soy with no adverse effects on masculinity. Some research has suggested that phytoestrogens may alter testosterone levels when men have prostate cancer, and indeed other research has suggested the hormone balance in men is disrupted in prostate cancer and thus may be more “susceptible” to being altered through diet. The concerns of feminization are frequently reported with stories on sex-changing fish in rivers (for example). Remember, studies on the sex-changes in fish and amphibians are not perfectly relatable to humans. In fact, many of these species are capable of changing sex during their lives when there is an imbalance in the numbers of males or females in an area. Obviously, this isn’t seen in human populations! We can assume that these animals control their sex hormone balance differently than we do.

With regard to androgens, there are several studies investigating plant-based sources and their effects on healthy men. You are correct in saying that there are relatively few studies discussing androgens compared to estrogens. The reason for that is their relatively new discovery. In 2005, a study on the herb Tribulus terrestris investigated how supplementation altered testosterone production. This plant was chosen based on its history in traditional folk medicine for its supposed effects on sexual function and physical prowess in men. In short, consumption of the plant extract (in either a high dose or low dose) did not alter androgen production. A study in 2000 demonstrated that the same extract had no positive influence on building muscle mass during resistance training. The first study which identified a potential androgen derived from plants was published in 2007. The plant in question was the Gutta-percha tree, Eucommia ulmoides. Their results showed the extract could weakly interact with the androgen receptor, but could also interact with the estrogen receptor. At the same time, large increases in prostate size were noted which is obviously a concerning outcome! The study concluded that the extract wasn’t acting in the same manner as bodily-produced testosterone, but was changing how testosterone worked in the body. Substantial follow-up study would be required before we understand how that happens, and what the outcome would be for a person. The chances of unintended consequences are enormous.

The human body operates with a certain level of hormones. Adding extra can have serious unintended consequences. In reality, the body attempts to regulate hormone levels and attempting to change them through supplementation can even lead to decreases in natural production to balance the excess. For example, steroid use leads to a decrease in testicular volume and function as the body attempts to decrease testosterone production. In short, while plant androgens can certainly be found and are likely bioavailable to some degree unless you have an actual deficiency through a lack of natural production, supplementation is unlikely to have the effects desired and come with some serious risks like an increased susceptibility to prostate cancer.

- Craig Ayre

 


 

Diseases

Question:

Can diseases be cured by other diseases?

Answer:

Before we get into the intriguing question of "one disease getting cured by other diseases", it would be appropriate to be clear what is meant by cure. The cure by a given treatment or surgical intervention is essentially termination of medical condition and disease symptoms providing relief to the patient. A disease remission is by contrast is a temporary termination of symptoms of an incurable disease. In complex diseases like cancer or systemic autoimmune disease, based on statistical analysis, one may equate long term remission with possible cure. It is not possible to consider a cure of an incurable complex disease per se. But it needs to be essentially seen in the context of remission, whether temporary or long term, that improves the quality of life of a patient. Based on current knowledge, it is reasonable to assume that disease pathogenesis of a condition may be modulated or altered by another disease condition with a positive or negative outcome depending upon synergistic or antagonistic pathological pathways. In some instances, it may result in remission of a particular disease condition while in others it may have just the opposite effect. It is difficult to predict, however, given a number of genetic, hormonal and environmental factors that underlie in such complex situations.

- Azad K. Kaushik

 


 

Hair DNA

Question:

I know DNA holds all of our genetic information and is used to transcript and translate into protein. Well, my younger sister was born with naturally straight as a board hair. When she was in high school, it started to curl! Her hair is really curly even 8 years later and we are all confused by the change. I know it's impossible for her DNA to change but maybe something else changed? 

Answer:

Hair texture – whether curly or straight, is a physical trait that is not directly controlled directly by genes. All hair is mostly composed of a protein called keratin. The strands of hair you can see (called the shaft) are not living material. Keratin, and all other proteins in the body, are made from a small number of chemicals called amino acids. One of these amino acids is called Cysteine. When two cysteines are near each other, they can form very strong bonds, which lock them together. This usually results in a bend being made in the protein the cystines are part of. The thickness of the hair shaft determines if hair will be curly or not. Imagine straight hair like a garden hose full of water. The thick hose makes bending difficult and it stays straighter. In hair, the thicker shaft means fewer cystines can link together and the keratin protein does not bend. A thinner, flatter shaft is more like a telephone cord. The flatter strand can coil and bend and this allows more cysteines to link together, locking the shaft into a curl. In fact, this is how a perm works. The hair is coiled around a curler and a chemical is added to break the cysteine bonds in the hair. The hair is kept in the curler and the chemical is neutralized which allows cysteins to bond again. Since they are wrapped closer together, they find new partners and lock the hair into a curl.

The hair shaft is produced from a follicle in the skin. It is this follicle that is responsible for hair growth, texture and thickness. So the question is, what decides if the follicle will make a flatter or more round shaft? The answer unfortunately isn’t completely clear. We do know that it comes down to the shape of the follicle. A rounder follicle leads to straighter hair. Genes do play a role in determining what shape follicle you can make, but that isn’t the whole story. You do inherit genes that play a roll in making a follicle that is flatter or rounder. These are inherited, one from each parent. Follicle shape is also influenced by environmental factors, most notably through hormones and certain drugs. Hormones have been known to affect hair for some time. High levels of androgens (like testosterone) can cause hair to grow excessively and to become curly. In women, who also produce testosterone, the effect can also be seen if their natural estrogen levels fall. Women naturally produce a smaller amount of testosterone, and the loss of estrogen can make its effects on hair more exaggerated. Other hormones and compounds are known to affect the follicle including retinoic acid (from Vitamin A), Vitamin D and thyroid hormones. Hair texture and thickness can change over a lifetime as we produce different hormones or become exposed to different conditions. In fact, conditions like stress or nutrition affect how our bodies work, altering our immune systems and hormone production, which can change hair growth and texture. Drugs that change the production of hormones, or affect how we can respond to them can have the same effect.  For example, certain medications for psoriasis can cause hair to grey. Estrogen or certain drugs to regrow lost hair, by comparison, can lead to hair darkening. In the same way, drugs like lithium can cause hair to straighten, or retinoids (Vitamin A-like chemicals) can cause curling.

In short, it’s not the genes that change but the environment. As your hair follicle responds to changes caused by drugs or hormones, it can change the shape of the hair shaft as its growing.

- Craig Ayre

 


 

Ebola Treatment

Question:

Why was the tobacco plant used to grow a vaccine for Ebola?

Answer:

Great question! The idea that tobacco can be used to produce a life-saving therapy may seem a little strange and futuristic, but actually, this type of technology has been under development for decades. 

Before I get to the answer, I would first like to mention that the Ebola therapy we’ve been hearing about in the news that is made in tobacco, is actually not a vaccine. In fact, it is a treatment that helps stop the Ebola virus from reproducing inside the human body. Therefore, it won’t provide lasting protection from Ebola, like a vaccine would, but it could help someone who is infected with Ebola to fight off the virus.

Now, in order to address your question, I have broken my answer into three parts; what type of drug is the Ebola treatment, why use plants, and why use tobacco.

What type of drug is the Ebola treatment?

The Ebola treatment being made in plants is made up of special proteins called monoclonal antibodies, which bind to the Ebola virus and help stop it reproducing. This treatment belongs to a type of drug called biologic drugs. Unlike many traditional drugs (such as acetaminophen) which can be made in a chemistry lab, biologic drugs are very large and complex and so far, we are not able to make them by synthesis. Instead, biologic drugs require living cells to make them.

To make a biologic drug, scientists start by using genetic engineering to put the DNA for the biologic drug into the cells of their choice.  Next, they grow a large quantity of the cells which make the drug, then purify the drug from the cells. Finally, the drug is put into a form that can be administered to a patient; often the drug is a liquid that is given through an intravenous injection over a defined period of time.

When biologic drugs were first developed, bacteria cells were the type of cells used. However bacteria can only make fairly small and simple biologic drugs. Therefore, over time, scientists have also learned to use mammalian, insect, yeast and even plant cells, which can produce larger, more complex biologic drugs. As well, these cells are often altered so that they produce biologic drugs that are more compatible with humans and are, therefore, more effective.

Each of these types of cells making biologic drugs has different advantages and disadvantages and each manufacturer will decide what type of cell they will use depending on the type of drug they want to make, how much they want to make and how much time they have to develop and produce the drug. Of course, there are always other issues that come into play, including the manufacturer’s experience and the patents they hold.

Why use plants?

Using plants to make biologic drugs may offer advantages such as faster, more flexible and cheaper drug production. Bacteria and mammalian cells are grown in “bioreactors”, which are huge stainless steel vats that must be maintained in sterile and carefully controlled conditions. Compare this to growing plants in a greenhouse, and you can imagine some of the potential cost savings, and increased flexibility in how much of the drug is produced. The manufacturer of the Ebola treatment is responsible for business decisions, and these may be some of the reasons why plants were chosen to make the treatment.

Why use tobacco?

Once a manufacturer has chosen to go with a plant production system, they then have to choose the species of plant. This choice will usually depend on many factors. The species used for the Ebola treatment is not actually tobacco, but a species called Nicotiana benthamiana, which is closely related to tobacco. This species is often chosen because it is easy to work with and grow and it can be made to quickly produce a large amount of a biologic drug.

- Fiona Cornel


What part of the brain controls cells?

Question:

Is there a part of the brain that controls cells? If so, when a person gets cancer, could the cause be that this part of the brain has died or can no longer detect when to stop producing cells?

Answer:

That is a very interesting question. The brain is part of the central nervous system. It helps control various processes of the body by sending signals to groups of cells through nerve fibres and hormones. Such processes include movement; balance; breathing; and regulation of the heartbeat, body temperature, blood pressure and kidney function. One area of the brain (the hypothalamus) may even control how fast we age. While the brain is very complex and has diverse functions, cells of the human body grow and divide due to properties inherent to the cells, their local tissue environment and external signal molecules found in the blood. So there’s no overt control from the brain, although cells of the body do grow as a result of hormones released by the brain, such as during puberty. A dividing cell can prevent its own development into a cancerous cell, that is, a cell usually “knows” when and how to stop dividing. Also, the immune system can detect and eliminate dividing cells that start to become cancerous. However, sometimes a cell will develop multiple abnormal changes that enable it to circumvent these protective measures, resulting in the formation of cancer.

- Dustin Johnson


Why does your blood look blue on your wrist?

Question:

Why does your blood look blue on your wrist?

Answer:

Thank you for the question. The body contains surface veins that lie just under the skin, making them easily visible at certain locations on the body. Although surface veins carry dark red, deoxygenated blood, they appear blue due to the light absorption and reflecting properties of the skin and veins. If you look closely, you can see blue-coloured veins on other parts of your body.

- Dustin Johnson

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