Wednesday, December 23, 2009

Wine Science

Just in time for the holidays, the newspapers seem to be very interested in the health effects of alcohol. The idea that red wine is good for you is nothing new, from the resveratrol to make you live longer (although you'd need to drink vats of wine a day to see a real effect), to the polyphenols that keep your heart strong, red wine seems almost like a miracle food. But what about the whites and sparklings?

Well, white wine doesn't seem to have the same qualities, though that has been debated. But according to the British press, champagne, and its cousins prosecco and cava, may actually be good for your heart. It's because these wines are made from black grapes (pinot noir, and pinot muenier), and according to Dr. Jeremy Spencer from Reading University, the qualities of the grapes do make it through into the finished product. Those qualities? Those would be the polyphenols. Polyphenols are small molecules that block the removal of nitric oxide from the blood stream, and nitric oxide is what keeps the blood vessels nicely dilated, allowing blood to flow through easily, reducing heart strain, and lowering blood pressure. The really good news in this is that unless you're drinking blanc de blanc (champagne made exclusively from chardonnay grapes) any sparkling wine made from a red grape will work (chocolate does too if that's your preference).

And talking of wine, according to the Telegraph, the lighting in a room will change how you perceive a wine. In a test using single bottles of reisling and subtly changing light colours, a group of German researchers found some remarkable results. First, if you use red lighting, then people will perceive a wine as sweeter than under other kinds of lights. And then, red of blue lighting will both increase the perceived price of a bottle of wine. why this would be is still unclear, but the effect seems to be real.

This shouldn't be a big surprise. For almost a decade now there have been studies showing how much our perception of wine is influenced by characteristics other than the taste of the wine itself. In fact, in blind tastings, even sommeliers have been known to be fooled by reds and whites, since the line for taste is frequently blurred. And time and time again, scientists have shown that the bottle a wine is poured from will influence how it gets described.

Even history can play a part, as a recent study showed. This looked at the genes of various varieties, and found that chardonnay (which, particularly in Europe, tends to get very little respect), was the child of gouais, a grape that was banned in parts of Europe for being a 'peasant's grape.' The fact chardonnay is a close cousin of gamay noir, shows how arbitrary some of these decisions can be.

When it comes right down to it, the key to wine is finding something you enjoy. And if it happens to be a red wine, or a champagne, then you're getting a health benefit at the same time!

Happy Holidays!

Wednesday, December 16, 2009

I'm Dreaming of a Green Christmas...

With the Copenhagen conference going on, and the heart of the holiday season, the question keeps coming up of how to keep being environmentally friendly while still enjoying the holidays.

And probably no issue is more highly debated at this time of year than what type of tree to put up, a real one or an artificial one? Assuming of course that you aren't going to forgo trees altogether.

The Victoria, Australia, government is pushing trees in pots, particularly the Wollemi Pine, a rare ancient tree. Not only does it keep your carbon emissions down, but it can help recover a disappearing species at the same time! Of course, here in Canada, Wollemi Pines aren't an option, but there are plenty of pine trees in pots that you could bring in and decorate.

But if you want to stick with tradition, which one should it be? Both sides have their proponents, although it turns out there are strong lobby groups for each option, pointing out the benefits and weaknesses of real versus artificial. The strongest argument I've found was in this article, where the carbon emissions of both are compared. The bottom line? You need to keep an artificial tree for 20 years if you want to compare its carbon emissions from construction with cutting down a local grown tree that was grown specifically for harvesting. And if you know that artificial trees begin to break down after about 9 years, and are mostly made in other countries and then shipped here, real seems to be the best option.

Then, once you've decided on the tree, there's the question of travel. Well, according to this BBC article, if you have to travel, and it's a few hours drive away, you might consider flying. Sure, flying uses a lot of fossil fuels, but a plane is actually more efficient in fuel conversion than a car, so if you fill a plane then your damage per person will be less than if each of you drive. Of course, this doesn't count if you're flying across the continent, or somewhere south, but that's a whole different issue.

In the end though, enjoy the holiday season. It's what we do all year round that really counts. A couple of weeks at this time of year is only a fraction of our carbon footprint. Try and be reasonable, maybe a couple fewer strings of lights, or a slightly smaller portion of meat, and less leftovers, but have a good time!

Wednesday, December 2, 2009

Getting Down and Dirty

OK, so I didn't blog for a couple of weeks, but this one is worth sharing...

Finally, some solid evidence to support the hygiene hypothesis. You've heard this one before, we need to eat dirt when we're small if we're going to be healthy.

It's an idea that has a solid biological underpinning. When we're small, our immune system is yet to properly develop. Exposure to all the 'normal' stuff in our lives (dirt, microbes and the like), trains our immune system to recognize the good from the bad. The problem, according to the hygiene hypothesis, is that if we aren't exposed to all the normal stuff when we're small, our bodies never learn the difference and so over react when we come in contact with those same materials later. That over reaction is the allergy response. The hygiene hypothesis suggests we should expose ourselves to far more dirt as youngsters if we want to be healthy in the long run. The problem with the hypothesis is that it's relied on epidemiological data for its proof. And, as any scientist can tell you, correlation (which is what you find with epidemiology) is not causation.

A couple of new studies are providing that causation. In a European study a group of researchers found that pigs housed outdoors for the first part of life had higher levels of lactobacilli and less immune activity in their guts than pigs kept in an isolation room. What does that mean? Lactobacilli are known to help prevent E. coli and Salmonella from colonizing the gut, which is good news if you want to avoid food poisoning. And as far as the immune activity, again, if the problem we're worried about is hyperactive immune systems, this is a good thing.

The second study is out of the University of California. Here a group of researchers looked at the bacteria naturally found on the skin. They discovered that Staphylococci sp. produce a compound that blocks a key step in the inflammation process. Which means that when you get a cut or scrape, it's the bacteria on your skin that are preventing your immune system from overreacting. That's a good thing: too much immune response and you'll get puffiness, rashes, heat and extra pain.

What all this is telling us is that we have this highly evolved, and tightly intertwined relationship with the bacteria that inhabit our body. These organisms block 'bad' bacteria from colonizing, and it's when they're not there that our immune system gets out of whack, leading to increased levels of immune response, aka allergies.

The irony is that on one level we appreciate that, as we see ads for yogurt containing high levels of lactobacilli. And at the same time, we live in a world that's selling buckets full of hand sanitizers, which are removing the very bacteria we need to protect ourselves.

What should we do? Follow our mother's advice, wash our hands, don't stick your fingers in your eyes, don't chew on your pen, and respect the fact we live in a bacterial world.

If we respect that, we'll only do ourselves good!

Wednesday, October 28, 2009


Hallowe'en this week, and for whatever reason spider science has been making headlines.

For instance, there's a new giant orb-weaver spider from Africa. Orb-weaver spiders are that archetypical spider that most of us think of when we think spiders. They're the ones we see sitting on the webs, that capture insects as they fly by, and are the type we put up as part of our Hallowe'en displays. We have plenty of orb-weaver species here in Canada, but this African one is in a league of its own. First of all, there's the size: the females of this particular species (Nephila komaci) grow to about 10-12 cm across, while the males are 1/5 that size. Can't picture that? It's about the size of the palm of a large man's hand! Then there's the web. Unlike most diaphanous spider webs, this one, over a metre across, is more string like, and is capable of catching small birds. Which the spiders will eat, although they prefer grasshoppers and other insects.

Another spider in the news is the Australian redback. In this case, it's a story of how lazy male spiders can win the mating game. This work comes from the lab of Dr. Maydianne Andrade at the University of Toronto, Scarborough, where they've been studying the mating habits of this relative of the black widow. The interaction of males and females in this species is unique to say the least, it'll be covered in some detail in my book when it comes out in the spring, but for now all you need to know is that the males have to court the females if they want to mate. And it's no short commitment, males have to put in almost 2 hours of attention if they want to mate before they get turned into a meal. Except for this new research, which shows that sometimes males can sneak in and mate without putting in the work, as long as another male has spent the time in courting. The bad news, for the hard worker, is that he doesn't get to mate, he's out-maneuvered by the other male.

And talking of sneaky spiders, earlier this year a spider was discovered making a decoy. By taking refuse and packing it together on the web, it can make a copy of itself to distract predators.

Why so much spider science? Part of it is probably just pure curiosity. But spiders are interesting for another scientific reason. They're a great model for studying evolution and behaviour. Take the male/female size difference. By looking at closely related spiders, we can understand what's driving this evolution in size disparity. The same with behaviour; spiders are a great system for looking at sexual conflict between males and females, and again, sometimes closely related species can behave quite differently, which lets researchers ask interesting questions.

If only they were a little cuter...

Wednesday, October 21, 2009

What's it all about?

Sex anyway.

From a biological perspective, sex is something of a mystery. First of all, it's inefficient. If you want to reproduce sexually, the first thing you need to do is get two individuals, one of each sex, together in the same place. Then, they have to like each other, at least enough to procreate. And, for males, that's the end of the biological role. Sure, humans, and plenty of other species, use males to help protect the offspring, or provide food, or for myriad other reasons. But if those males weren't there using up resources, there could be more females, and potentially twice as many offspring around. More offspring means a greater chance of success for a species.

Which is where researchers have looked for the problems that might be associated with asexuality. By the way, for the purpose of this, I'm going to talk about asexuality in general terms, in fact there are two quite distinct forms, true asexuality, where reproduction is by either fission (like in bacteria) or parthenogensis (where females produce eggs that turn into fully functional organisms), or self-fertilization (where an animal produces both eggs and sperm and is able to fertilize their own gametes).

But back to the problems. The first one is the build up of potentially damaging mutations. This is sometimes referred to as Muller's Ratchet. Basically, the theory is that copying between generations isn't perfect. Each new generation will pick up a few mutations from its parent. That means as time passes, the number of mutations will increase. On its own, each mutation is not a particularly big problem, but if you collect enough, your health is going to suffer, and the species will become less viable. Remember also, that mutations are generally irreversible, so it's not like they are going to fix themselves from one generation to the next. The male then, the theory goes, helps get rid of these mutations by bringing in new genetic information that mixes with the mothers, and hopefully slows the mutation rate.

There's a second theoretical problem that relates to the enviroment. In this problem, you have a species that's wonderfully adapted to where it's living. But then something changes. It might be a new virus that the species hasn't seen before. Or the temperature might start to change. Whatever it is, if you don't have a gene that allows you to adapt, you're in trouble. Males in this case are often the source of the needed genes that either allow resistance or adaptation.

At least those are the theories. What Dr. Patrick Phillips and his team from the University of Oregon wanted to figure out was whether the theories were true or not. In an advanced online publication in Nature Magazine he took C. elegans and manipulated it to turn it into a self-fertilizing hermaphrodite. Sure enough over time, these worms built up mutations, showing the first theory has merit. Then, when challenging the hermaphrodites with a bacterial pathogen, again they were unable to resist infection and disease. In both experiments, controls with hermaphrodites that could outbreed with males did just fine, showing that males do prevent these problems.

So, men can take heart, biologically we do have a function. And of course beyond the basic genetic role, human males, and males of many other species have expanded their role to protection and sharing in the general raising of young. Which is good, we wouldn't want to end up like the Triplewart Seademon. Males of this species are simply a parasitic bag of sperm attached to their female...

Wednesday, October 7, 2009

Nobel Week

My favourite week of the year!

I'm going to do things a little differently in the blog this week. I could describe the winning nobel prizes, but there are plenty of sources for that information. Instead, I'm going to talk about why I think there's still room for the Nobel categories.

There's been some debate this year (as there is every year) about the relevance of the prizes today. There are plenty of fields, important to modern science, that aren't captured in the Nobel's list of possibilities. Environmental research, for instance, is not captured by Medicine, Physics or Chemistry. There's an argument to be made that the categories should be redefined and broadened to recognize fields that didn't exist in the time of Nobel himself.

I'm going to argue against that. Well, not vehemently, because if there were more categories, that would only be a good thing. But when you look at this year's awards, it seems to me that the Nobel committee does pay attention to relevance.

All of these three science awards are for relatively recent work. And in each case, real practical outcomes that affect vast numbers of people, have been achieved. Telomere research has taught us about aging, and cancer and lots of diseases. The CCD and fibre optics have changed communication forever, and we're only scratching the surface of their potential. Ribosomes are a fundamental building block in the cell, and we have a whole class of antibiotics that owe their existence to the understanding of the ribosomal structure. But in all these cases, none of the practicl outcomes would have been possible without the fundamental discoveries of the researchers. In the end, that's what's great about the Nobel prizes. At a time when a lot of research funding is headed to 'applied' research, those who perform basic work can still be gratified to know that their fundamental science will be applauded and recognized by the most famous award of all.

Keep the Nobels, but make more prizes too!

Wednesday, September 30, 2009

Recession's Silver Lining

Here's some economic news that might seem a little odd. Recessions (and depressions) may actually be good for your health. At least, that's the result of a study in the Proceedings of the National Academy of Sciences that's looking at the connection between the economy and certain health statistics.

In this particular study, the research team from the University of Michigan's Institute of Social Research looked at two health measures: life expectancy based on birth year, and death from non-natural causes (in this study specifically heart disease, kidney disease, tuberculosis and traffic accidents). These are fairly standard measures of health, and can give you a snapshot of how well a population is fairing. When they compared these health measures to the economic picture over time, a few interesting points fell out.

First, when you look at longevity through the 1920s it actually drops as the decade progresses. Then, in 1929, as the great depression begins, it jumps back up. In fact life expectancy increased an average of about 8 years over this period, which is a big change. Also the deaths from non-natural causes dropped right down during the great depression. Both flipped again once the depression was over, that is until 1936, when there was another economic downturn, and once again we see an improvement in overall health.

This seems counter-intuitive, if you look at the difference between developing and developed countries, it's easy to see how lower economic development generally maps onto lower quality of health. But the researchers point to China, where there are relatively high standards of health, as well as increasing economic development. On first blush, this would support the idea that money and health go hand in hand, except that health development in China happened decades before the economy improved. This suggests you can't trust cross-border comparisons when looking at the relationship between health and finance.

Secondly, another criticism could be that the effect on the poor is being washed out in the bigger picture, when you look at the rich and the poor together. After all, in a recession, the rich tend to get richer, and the poor, poorer. But in this study, the research team separate out the effects on whites and non-whites (which are, for the historical context, reasonable stand-ins for economic status) and found that overall non-whites had better health during the depression. So much for the poor suffering more.

What's behind all this? The answers are still speculative, but interesting. Here's one scenario. People have less free cash during a recession or depression, so they tend not to travel as much. In the 30s that would mean fewer car trips. Fewer cars on the road, fewer accidents. And without money, less alcohol gets consumed, which means less kidney disease. A lack of pollution (because the factories are shut down) could mean less lung disease in general, and from that less tuberculosis. And finally for heart disease, well, if you have a job, you're probably not being forced to work as hard as you once were, which means less stress, and fewer heart problems. Also, those without jobs usually had strong support at home, as well as in their local community, again lowering stress. With parents at home, that could contribute to raising small children, and given how the first few years are critical for long term survival, that may help explain why children were more likely to live until adulthood, skewing the statistics towards a longer life.

But while this is persuasive for looking at the depression, how well it maps onto the current recession is a difficult question. Causes of death are very different, cancer, for example, didn't make the list in the 1920s but is very important today. Researchers are not in agreement over how applicable this is to the current world. But what about looking to really figure out what was behind the improvements? If we can work out that, maybe that will help us come up with ways to improve everyone's life, recession or not.

Wednesday, September 23, 2009

Bearing False Witness

Time to combine segments from my two lives, that of a law student, and that of a journalist.

Key in any trial is the testimony of eye witnesses. In fact, in life in general we pay a lot attention when someone says, "I saw it with my own eyes." But how reliable is that testimony? Obviously the further away you get in time, the fuzzier the memory is going to be. But in some cases it isn't about memories becoming fuzzy, it's about them changing altogether.

The concept of a false memory is nothing new. A study by Elizabeth Loftus and colleagues using Bugs Bunny showed that it's possible to convince people that they saw Bugs wandering around Disneyland when they visited the park, even though he's the creation of Walt Disney's competition. The memories seem real though, people reported seeing the rabbit with Mickey Mouse, or shaking his hand, but that couldn't have happened.

You could argue that this isn't surprising. In most cases, it would have been a long time since the original visit that was now being remembered, but that's not the case for the latest work. The study by Dr. Kimberley Wade demonstrated that if you show someone video of an event, but video that's been altered, then that changed version will frequently replace their own memory. Suddenly they're remembering details of something that never actually happened.

That's concerning. Today it's very easy to doctor photographs or videotape with a home computer, and that can be used to influence a person's thinking. Even conversations or still images can change memory. If you look at how most journalism or police work is done, it's rare to get to a witness immediately, and any interference before you get a statement down on paper could lead to a false memory, that the witness sincerely believes. And in court cases, it can be months or even years until they get into court, so who knows how much memory can change.

Even for the rest of us, there are concerns. Marketers love drawing on nostalgia, it's a great way to make us buy products. What if they position products so that it looks like you have used it before. Suddenly you're in the grocery store buying stuff you remember, even if in reality, it's completely novel.

Can you trust your memory? Not completely, so if you want to really keep track, either write it down, or horde your video and still pictures carefully. You never know when your memory might be changed...

Wednesday, September 16, 2009

Showerhead Slime

Earlier this week, the news media picked up on a story in the Proceedings of the National Academy of Sciences. Basically, the story showed that Mycobacterium avium and related Mycobacteria (but, happily none associated with TB) were present in the showerheads of homes across the US. In and of itself, this shouldn't be a surprise, M. avium is present in the water supply, so there's no reason for it not to be in showers. The more interesting result was the level, relatively concentrated, and well above the background. Not only that, but when the researchers tried bleaching the shower heads, this only made the problem worse. M. avium is resistant to bleach, so there's a selection that goes on, killing other organisms and leaving a population of cells that's largely made up of this and related species.

So far, not a lot to concern anyone, unless they're licking their showerheads. The problem comes with aerosols. Aerosols are small droplets of water (or any material really) that float in the air. Thse can contain bacteria, and can be inhaled. Suck these droplets into your lungs (the idea goes) and maybe you'll take in some of the dangerous bacteria at the same time. If you're immune compromised (through being very young, very old, or having a damaged immune system) and there's a chance you'll develop lung disease.

That was the story in most of the media, and it generally ended with the advice to change your showerhead every 6 months or so, and to replace what you have now with a metal showerhead if yours is made of plastic.

But that's not the full story. In the paper itself, the researchers did look at aerosols, and found that the levels of bacteria were no higher than in the water that went into the shower in the first place. Their suggestion is that the bacteria are cleared in the first few moments after the shower is turned on, but as the paper suggests, this needs a lot more research before it can be confirmed. It's also possible, although not discussed in the paper, that bacteria in the showerhead aren't released as aerosols at all, but again, there's no real data to confirm or reject this.

The other technical consideration is that the detection in this study was indirect. Not that this is a problem with the study itself, detecting microbes from the water column is incredibly difficult. But it is a proxy measure (in this case looking at RNA), which doesn't tell you everything about the organism. For example, these bacteria are living as part of a biofilm (a complex community of bacteria living on a surface), and we know that biofilm living is very different than free living, which may affect how ready these organisms are to cause infection. Again, it doesn't prove that there's nothing going on, but does indicate we need more research to determine what the presence of these organisms really mean.

Overall, the paper is a good one, and it does remind us that we live in a world that's full of microbes. That's important to remember, and certainly for the immunocompromised it has to be taken very seriously, and we should respect the bugs around us. But at the same time, there's no real reason to live in fear. What our parents taught us as kids: wash your hands, sneeze into your sleeve, and don't spit on people, are the kinds of rules that will keep us clean. We've evolved for millions of years to live with bacteria, and we wouldn't survive without them. In fact, over cleaning can cause more problems than just carrying on with life.

So keep showering! If nothing else, it will prevent you from offending your friends.

Wednesday, September 9, 2009

Learning can be addictive

One of the toughest problems smokers face when trying to quit is the association of smoking with other activities. For some, it might be wanting a cigarette after a good meal. For others, getting into the car on the way home from work might stimulate the desire to light up. Whatever it is, the urge is often strong, and provides a real barrier to quitting.

If you think about it though, it's not a logical connection. There's no reason why getting into the car should lead you to smoke. Lots of people don't have this urge, even lots of smokers. So what's going on? The key here is learning. For whatever reason, the smoker has learned to associate the activity, the people or the place with the good feelings that come from lighting up a cigarette. And so they continue to smoke, or at least want to smoke.

That's why psychologists who are helping people quit drugs of any kind try to dissociate behaviours from their cues. Whether it's introducing a substitute like gum, or having a person avoid the places where they like to indulge, it's all about changing the behaviour and learning new patterns.

So far, none of this is new. But Dr. John Dani, from Baylor College of Medicine, wanted to look under the hood and figure out what's going on inside the brain when someone takes an addictive drug. Why is it that we're so good at learning to associate addictive substances with cues, when we're not normally that successful?

What he found out is published here.(paper available September 10, 2009)

Find out more about Dr. Dani's Lab here.

In a series of experiments, Dr. Dani and his colleagues were able to show that nicotine (and by extension other addictive drugs) was able to enhance learning. That is, connections in the parts of the brain we associate with learning new things were stronger and more numerous when there was nicotine in they system, compared to controls. Although that needs to be qualified. This only worked when dopamine levels were also raised, showing the connection between the role of dopamine in learning, with the addictive substance.

This is an almost sinister finding. Our brains need to be able to learn, that's what keeps us alive. And dopamine is an important part of this learning process. After all, dopamine is associated with pleasurable experiences, and it makes good evolutionary sense to seek out food, sex and a safe place to sleep. Dopamine helps us find all of these, by making them pleasant. But these addictive drugs are taking over that system, and making drug seeking not just a pleasant experience, but one that we remember vividly. No wonder it's so hard to break an addiction.

This has some important implications. First of all, it reminds us that addiction is a physical thing, not just a weakness of will in the person who's trying to quit. But there's another angle to this, and that's understanding learning itself. By studying how these drugs interact with dopamine and the brain, maybe we can learn what's going wrong in various dementias, or Parkinson's disease (which is characterized by loss of dopamine), and in the long run, come up with treatments for them.

What this isn't, is a suggestion that smoking is good for you. The memories you form encourage you to remember smoking, and not much else, which can lead to all kinds of other health problems.

Wednesday, September 2, 2009

Musical Monkeys

capuchin monkey courtesy Bryce Richter, University of Wisconsin, Madison
OK, so it's not going to be hitting the top of the charts any time soon, but Dr. Charles Snowdon from the University of Wisconsin, Madison, thinks he knows what cotton-top tamarin monkeys like. Working with musician David Teie, he's created songs that both agitate and please these primates.

For the University press release, you can go here.

For the music itself, you can go here.

What I think is interesting about this story is how it fits into a curious evolutionary story. Music is present in most cultures around the world. When something is that widespread, then there's a good chance it exists for some kind of evolutionary reason. But music has created a problem. Many evolutionary traits can be seen in our closest relatives, the other primates. Music, both in terms of creation and appreciation, seemed to be missing. Yes, I know, people's pets will seem to recognize music, and even sing or dance along (remember the dancing parrot), but this is something deeper. Music seems to affect us at an emotional level, but play the same thing to a monkey and nothing.

That is until Dr. Snowdon's study. In this case, he's using music that's been created for the monkeys. It doesn't sound like music to our ears, but it contains tones that mimic sounds the monkeys naturally make. So, for them a rising tone and staccato notes mean danger, and long steady descending tones mean peace and calm. Create music with these patterns, and the monkeys respond in kind.

Now we have a possible evolutionary link. Like monkeys, we communicate emotion through our tone of voice, that's partly why email is a rotten way of communicating sarcasm. Could music be the natural extension of this? Not just to tell others how we're feeling, but to manipulate their emotions as well. It works in the monkeys, we know music does it to us too, were the first musical notes just a way of controlling the crowd?

If nothing else, this study opens the doors to studying music in other primates. All it takes is knowing what sounds are going to create themes they'll find interesting.

Oh, and one other thing. There was one type of human music these monkeys found soothing. The melodies of Motley Crue!

Image: Cotton-top tamarins grew calmer after they heard music compositions based on their own calm, friendly calls. But the monkeys became more agitated when University of Wisconsin-Madison psychology professor Charles Snowdon played music that contained elements of their own threatening or fearful calls. Courtesy Bryce Richter/University of Wisconsin, Madison

Sunday, August 30, 2009

As Requested

For the last 5 years, I've offered up a weekly column on CBC Radio One, with the latest of science stories. For the last 2, I've got harassed (nicely) of course, to blog about my stories, with links to more information, and more comments on the stories, beyond what was on air. So here it is. Each week, I'll post background and science comments. And if any other science stories catch my attention, well, I'll talk about them here too. Enjoy!