* Human Guinea Pigs * Drongo Mimics * Immune Collateral Damage * Getting a Grip with Coffee Grounds * Fact or Fiction: Candy & Cavities *

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Human Guinea Pigs

Imagine being a perfectly healthy person, and agreeing to take a powerful prescription drug, designed for a condition or disease that you do not have.  Well, it turns out that's the way we test the safety of new drugs, before they get approved. Many individuals willingly sign up for these drug trials - trials that can pay thousands of dollars. They call themselves "lab rats", and Toronto freelance science writer Alison Motluk has a look at the lives of these human guinea pigs.

She speaks with Steve Scholtz, a stand-up comic in Toronto, who supplements his income by volunteering to take part in Phase 1 clinical trials for various drugs. He's been doing it for years, and says the side effects from the drugs can be quite severe.

She also spoke with Brandon, an American "lab rat", who makes his living from these drug trials. He says he made $30,000 last year from trials, but had to drive from Seattle to Texas to New Jersey, to find trials that he could enroll in. The best ones pay as much as $5,000. But he worries about the long-term effects and would like to find a better job.

Dr. Carl Elliott is a bioethicist at the University of Minnesota, who has investigated these drug trials. He says the pharmaceutical companies that run the trials also hire the ethics boards that oversee them, leading to a conflict of interest. He says more supervision and oversight is needed.
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Related Links

• Dr. Elliott's book, White Coat, Black Hat
• Dr. Elliott's article about human guinea pigs in The New Yorker
• US FDA rules for volunteering in clinical trials
• Should volunteers be paid according to risk? Article in BMJ
• Web site for Lab Rats
  
  

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Drongo Mimics

Fork-tailed drongo, courtesy Dr. Thomas Flower

The fork-tailed drongo is a small aggressive bird that lives in Africa.  As it turns out, the drongo is also deceitful and tricky, according to Tom Flower from the Department of Zoology at the University of Cambridge in England.  He spent eleven months in South Africa's Kalahari Desert studying the drongo.  It has an alarm call that it uses for predators.  But it emits the very same alarm call, in a false way, to trick meerkats and other bird species into thinking there is cause for concern, especially while they are feeding.  As the animals scurry for cover, the food is abandoned and the drongo reaps the benefit.  But like the 'boy who cried wolf', the drongo's false alarm can wear thin, so it has learned to mimic the alarm of many other species, in order to continue the deception.  

Related Links

• Paper in Proceedings of the Royal Society B
• Tom Flower's web page
• The Kalahari Meerkat Project
• Not Exactly Rocket Science blog

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Immune Collateral Damage

Immunologists have long been puzzled by "sterile inflammation", which occurs when the immune system responds to an internal injury, such as a muscle sprain, heart attack or stroke, with the same kind of powerful immune response that is used against a bacterial infection.  Immune cells flock to the site of the injury and their inappropriate response may aggravate the damage that's already occurred.  Dr. Paul Kubes, the Director of the Snider Institute of Infection, Immunity and Inflammation at the University of Calgary, has been looking for the signals that summon these immune cells when sterile injury occurs.  He's found that one of the triggers seems to be fragments of protein from mitochondria released from damaged cells.  Dr. Kubes suspects that, to the immune cells, these mitochondrial proteins may look like signs of bacterial infection, and that this may explain the immune system's unfortunate reaction.

Related Links

• Paper in Science
• News from the University of Calgary
• Dr. Kubes' lab

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Getting a Grip with Coffee Grounds

Robotic hands are complex devices that need to know a lot about what they're grabbing, dextrously manipulate their "fingers" and carefully apply the right amount of force, in order to do anything. Dr. Heinrich Jaeger, a physicist from the University of Chicago, and his colleagues, have made a new kind of gripper that avoids all this complexity.  It's a flexible bag full of ground coffee.  The new device exploits a phenomenon known as "jamming" that occurs in granular materials when the grains are compressed.  The material's behaviour shifts from a flowing, liquid-like state, to a solid.  In the gripper, when the bag is loose, it conforms to the shape of objects it encounters.  Then a little air is evacuated from the bag, and it stiffens into solidity around the object, which it can then pick up.

Related Links

• Paper in PNAS
• News from the University of Chicago
• Dr. Jaeger's Lab
• Discovery News
• Wired Science

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Fact or Fiction: Sugar Causes Cavities

Another episode of our occasional feature, Science Fact or Science Fiction. From time to time, we present a commonly held idea or popular saying - and ask a Canadian scientist to set us straight on whether we should believe it or not.  And a week after Halloween, with lots of leftover candy still lying around, we have a very topical belief to put to the test:  - "More sugar leads to more cavities". 

To get at the root of this idea, we contacted Dr. Ferne Kraglund, an Assistant Professor in the Faculty of Dentistry at Dalhousie University in Halifax. She says it depends on how long the sugar is in your mouth.   


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Theme music bed copyright Raphaël Gluckstein, Creative Commons License by-nc-nd-2.0