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March 8, 2013

Lousy Sleep Isn’t Good For Your Body, Either

sleeping man

A good night’s sleep is worth the effort. Photo courtesy of Flickr user Kaptain Kobold

This weekend, most of us Americans will lose an hour of sleep when we push the clocks ahead to swing into Daylight Saving Time.

That may not seem like much–the Academy Awards were three and a half times that long–but research suggests our bodies wouldn’t agree. A recent study by two Michigan hospitals found that they treated almost twice as many heart attack victims on the first day of Daylight Saving than on a typical Sunday. And if past behavior holds true, there will be a bump in traffic accidents on Monday because, as researchers have suggested, more people take “microsleeps” that day, due to the disruption of their body clocks.

Clearly sleep, or lack thereof, is a key component of psychic and physiological balance, although it wasn’t all that long ago that most scientists felt it wasn’t worth a lot of attention because frankly, it didn’t seem like all that much was going on. Now we know better–there’s a lot happening inside our brains and, apparently, our bodies, too when we’re snoozing.

Unfortunately, that hasn’t made us act much smarter when it comes to our sleeping habits. We’ve been hearing for years that our bodies need a good eight hours a night, but, according to a Centers for Disease Control report released last year, almost a third of working adults in America get only six.

So as David Randall, author of Dreamland: Adventures in the Strange Science of Sleep, noted in a Wall Street Journal column, we’re seeing a boom in sleep aids, energy drinks, expensive mattresses designed to help us find our right “sleep number”, sleep-tracking devices and “fatigue management consultants.” That’s right, fatigue management consultants. A lot of Fortune 500 companies are now using them to track how sleep habits are affecting employee performance and safety records.

When cells go bad

Most of us are painfully aware of the mental and emotional costs of cheating ourselves of sleep. Who among us hasn’t felt the stupidness of fuzzy brain? The physical effects, though, are harder to distinguish. There’s plenty of research now that links poor sleeping habits to obesity, diabetes, heart disease and high blood pressure. But they develop over time–which would seem to suggest that it would take years of bad sleeping to damage our health.

Sadly, that doesn’t seem to be the case. A study just published in the journal Proceedings of the National Academy of Sciences found that getting too little little sleep just a few nights in a row can disrupt hundreds of genes, including those tied to stress and fighting diseases.

Scientists at the Surrey University Sleep Research Center in England subjected 26 volunteers–men and women between the ages of 23 and 31–to two very different weeks of sleeping. One week they were permitted to stay in bed only six hours each night. The other week they were allowed to sleep as long as 10 hours every night. Then the researchers analyzed cells in the volunteers’ blood, focusing on changes in RNA, the molecule that carries out DNA instructions through the body.

What they found surprised them. They discovered that not getting enough sleep changed the patterns in the way genes turned on and off. Overall, 711 genes were expressed differently when people were sleep-deprived: 444 genes were suppressed, 267 were stirred up. And the ones that became more active were genes involved in inflammation, immunity and protein damage.

Plus, when sleeping time was limited to six hours, the genes that govern the body clocks of the volunteers changed dramatically. Almost 400 genes stopped cycling in a circadian rhythm altogether, a disruption that could throw sleep patterns even more out of whack.

Not even Derk-Jan Dijk, the director of the Surrey sleep center, expected to see that. “The surprise for us,” he said, “was that a relatively modest difference in sleep duration leads to these kinds of changes. It’s an indication that sleep disruption or sleep restriction is doing more than just making you tired.”

You snooze, you don’t lose

In honor of National Sleep Awareness Week, which ends Sunday, here are six other recent sleep studies of which you might want to be aware:

  • One man’s pizza is another man’s slice: A study at Uppsala University in Sweden determined that men who were sleep-deprived invariably chose larger portions of food than they did when they had a good night’s sleep.
  • So that’s why my pillow hurts my head: According to research at the Henry Ford Hospital in Detroit, not getting enough sleep can lower your tolerance for pain. Volunteers who were allowed to sleep nine hours a night for four nights were able to hold their fingers to a source of heat 25 percent longer than study participants who weren’t permitted to sleep more than seven hours.
  • Now that’s a vicious cycle: Meanwhile, at the University of California, Berkeley, scientists said they’ve found a clear link between aging brains, the poor sleep of elderly people and memory loss. After comparing the brains and memory skills of young study participants and older ones, the researchers determined that age-related brain deterioration contributes to poor sleep and that leads to memory problems.
  • But wait, there’s more bad news: And in Norway, analysis of the medical histories of more than 50,000 people showed that people who said they had trouble falling asleep or remaining asleep were three times more likely to develop heart failure than those who reported no trouble sleeping.
  • If only they could sleep right through it: Research from Harvard Medical School suggests that nursing home residents who take sleep aids, such as Ambien, are more likely to fall and break a hip than residents who aren’t taking any meds for insomnia.
  • Did I mention that it makes you stupid about food?: Finally, two studies last year showed why sleep deprivation can lead to excess pounds. One discovered that lack of sleep can prompt bad decisions about what food to eat. The other study found that when subjects were permitted to sleep for only four hours, the reward section of their brains became more active when they were shown pictures of pizza and candy.

Video bonus: Here’s a recent ABC News piece on why bad sleep leads to bad memory.

Video bonus bonus: Okay, after all this grim science news, the least I can do is share an oldie-but-goodie stop motion clip of real fun in bed. Sleep tight.

More from Smithsonian.com

Experiments Show We Can Really Learn While We Sleep

Taking Control of Your Dreams




March 1, 2013

The War on Cancer Goes Stealth

nanomedicine

Zinc oxide nanoparticles. Courtesy of National Institutes of Health.

So, we’re 42 years into the War on Cancer, and while the enemy remains formidable, our strategy is shifting into yet another phase.  We’ve been through the equivalent of hand-to-hand combat–surgery–carpet bombing–radiation–and chemical warfare–chemotherapy.

Now the fight is about stealth.  Instead of concentrating on blasting away at cancer cells, or poisoning them, you’re more likely to hear cancer scientists talk about “Trojan horses” or “cloaking strategies” or “tricking” the immune system.  All are cell-level ploys hatched through nanomedicine–medical treatment gone very, very small. How small? At the nano level, about 5,000 particles would be as wide as a human hair.

We are not the enemy

Okay, so we’re in beyond comprehension territory here.  But let’s not get hung up on size; let’s focus on deception.

The latest example of microscopic trickery was laid out last week a paper from researchers at the University of Pennsylvania. One of the most appealing aspects of nanomedicine is that it allows scientists to deliver drugs directly to a tumor instead flooding the whole body with chemotherapy. Unfortunately, the immune system sees the nanoparticles as invaders and tries to clear them away before they can go to work on the tumor cells.

The trick was to make  the “sentry cells” of the body’s immune system think that the drug-delivering nanoparticles were native cells, that they weren’t intruders. The researchers did this by attaching to each nanoparticle a protein that’s present in every cell membrane. And put simply, it sent out a “don’t eat me” message to the body’s guard cells.

The result, at least in mice, is that this technique  dramatically improved the success rate of two different kinds of nanoparticles–one that delivered tumor-shrinking drugs and one filled with dye that would help doctors capture images of cancer cells.

Meanwhile, earlier this year, scientists at the Methodist Hospital Research Institute in Houston announced that they had found their own way  of letting nanoparticles fool the immune system.  They developed a procedure to physically remove the membranes from active white blood cells and drape them over nanoparticles. And that “cloaking strategy” was enough to keep proteins that activate the immune system from doing their job and ordering it to go repel the invaders. The researchers believe it will one day be possible to harvest a patient’s own white blood cells and use them to cloak the nanoparticles, making it that much more likely that they’ll get to their target without being attacked.

As magical as all this can sound, nanomedicine is not without risk.  Much more research needs to be done on the long-term impact of nanoparticles inside the body.  Could they accumulate in healthy body tissues?  And if they do, what effect would it have? Can those tiny particles  now seemingly so full of promise,  eventually turn toxic?

Still plenty of questions about nanomedicine, but it’s feeling more like an answer.

Small talk

Here are six other ways in which thinking small is moving medicine forward:

1) But first, remove all jewelery: At the University of Minnesota, scientists are experimenting with nanoparticles and magnets to fight lung cancer.  They’ve developed an aerosol inhalant that a patient can draw into his or her lungs with a few deep breaths. And that carries iron oxide nanoparticles to tumors inside the lungs. Then, by waving a magnet outside the body, they can agitate the particles so that they heat up enough to kill cancerous cells around them.

2) A new shell game: A team of engineers at UCLA has developed tiny capsules--about half the size of the smallest bacterium–that are able to carry proteins to cancer cells and stunt the growth of tumors. And the nanoscale shells degrade harmlessly in non-cancerous cells.

3) Gold’s fool: And at Northwestern, researchers say they’ve found a way to use gold nanoparticles to effectively fight lymphoma. They fool the lymphoma cells into thinking they contain high-density lipoprotein (HDL), which the cells need to survive. The gold nanoparticles bind to the cancer cells and starve them of cholesterol.

4) Way better than Krazy Glue: In Germany, scientists have invented a paste made of nanoparticles that they say can makes broken bones repair themselves faster. The paste contains two growth-factor genes that enter cells and accelerate bone healing.

5) Alas, it can’t help you find meds you dropped on the floor: While technically not nanomedicine, a small smart pill that tracks if people are taking their medications correctly could soon be on the market. Approved by the FDA last year, the pill contains a tiny sensor that interacts with stomach fluid and sends a signal to a patch on a person’s body. Taken with a real medication, the smart pill transmits information about the other med, particularly when it was ingested, to a smartphone. But it also sends physiological data, including heart rate and activity level.

6) Body heat gone bad:  Along the same lines, firemen in Australia have started taking a tiny capsule to protect them from being overcome by heat.  Sensors in the pill are able to take their core body temperatures in real time and relay that data to a smart phone.  And that has led to changes in firefighters’ work patterns, including the length of time they are exposed to blazes.

Video bonus: Still not clear on nanomedicine?  Here’s a TED talk on how it’s being used to fight cancer by Mark Davis, a leading expert on the subject and a chemical engineer at the California Institute of Technology.

More from Smithsonian.com;

Medicine Goes Small

New Device Can Measure Mass of Single Molecule




February 25, 2013

Mapping How the Brain Thinks

brain mapping

The challenge is to figure out how all that wiring works. Image courtesy of Human Connectome Project

A year and a half into his presidency, John F. Kennedy challenged U.S. scientists to get Americans to the moon by the end of the decade. At his recent State of the Union address, Barack Obama hinted at what could become his version of reaching for the moon–he’d like scientists to solve the mystery of the brain.

Obama’s mission would be a heavier lift.

He didn’t go into much detail, other than citing brain research as a stellar example of how government can “invest in the best ideas.” But last week a story in the New York Times  by John Markoff filled in a lot of the blanks. Obama’s grand ambition is something called the Brain Activity Map–it’s already being referred to simply as BAM–and it would require a massive collaborative research effort involving neuroscientists, government agencies, private foundations and tech companies, with the truly daunting goal of figuring out how the brain actually generates thoughts, memories and consciousness.

An answer for Alzheimer’s?

The White House is expected to officially unveil its big plan as early as next month as part of its budget proposal. The speculation is that it could cost as much as $3 billion over the next 10 years.

Now, it may seem a strange time to be pitching projects with a $300 million-a-year price tag, what with the budget-hacking sequestration expected to kick in later this week. That’s why even though Obama was light on the details, he did make a point of comparing the brain-mapping mission to the Human Genome Project–a major research initiative financed by the federal government to map all of the genes in human DNA. It ultimately cost $3.8 billion, but it reached its goal two years early, in 2003, and through 2010, according to an impact study, returned $800 billion to the economy.

No question that BAM could have a profound impact in helping scientists understand what goes on in the brain to cause depression or schizophrenia or autism. And it certainly could be a boon to pharmaceutical companies that have spent billions, without luck, to find a cure for Alzheimer’s disease. Since 1998, there have been more than 100 unsuccessful attempts to find a treatment for Alzheimer’s, which by 2050, is expected to affect 115 million people around the world.

It’s all about the tools

Clearly there are plenty of medical reasons to try to unravel the brain, but what, realistically, are the prospects? Sure, brain scans have helped scientists see which parts of the brain are more active during different types of behavior, but that’s a 30,000-foot view. It tells them next to nothing about how individual brain cells transmit information and even less about how neural networks transform that into behavior.

In recent years, researchers have made big strides in understanding how the brain is organized through the Human Connectome Project, funded by the National Institutes of Health. But that’s designed to create more of a static map of neural connections.

The next crucial step is to be able to see, in real time, how information is processed through those connections and which different neurons become part of that process. Or as Harvard biologist George Church, one of the scientists who proposed BAM in a paper last year, has explained it: “We don’t just want to see the wires, but also the messages going over the wires.”

The key is how quickly technology can be developed that will allow scientists to follow a thought process by recording every blip of every one of the thousands, and possibly millions, of neurons involved. Current technology enables them to record the activity of roughly 100 neurons at a time, way too small a slice of the neural network to help explain much of anything. But, as Greg Miller noted in a recent piece on the Wired website, several cutting-edge biological or nano-tools are in the works, including one that could “pack hundreds of thousands of nanowire electrodes into flexible sheets that conform to the surface of the brain and eavesdrop on neurons with minimal tissue damage.”

Is bigger really better?

A lot of neuroscientists will be thrilled if BAM gets funded. But not all. Some have already pointed out that you really can’t compare it to the Human Genome Project, nor the mission to the moon, for that matter. Both of those endeavors, while very challenging, had clearly definable goals. But how do you identify success for BAM? Would being able to record the activity of hundreds of thousands of neurons really explain how thinking happens? No one really knows.

Other scientists are concerned that BAM, with its high profile, could drain dollars from other neuroscience research. Some writers have even raised the specter of mind control, particularly since one of the government agencies that would be involved is DARPA, the Defense Department’s agency that funds experimental technology.

Gary Marcus, writing in the The New Yorker, makes the case that a project like BAM might be more effective if it wasn’t so monolithic. He argues that it should be broken up into five smaller projects, each one focused on a different aspect of brain function.

But he also warns that should Congress balk at ponying up the money for a major neuroscience project, it runs the risk of sparking, ironically, a brain drain. In January, a group of European countries committed more than $1 billion to their own huge neuroscience endeavor called the Human Brain Project , which will try to simulate all the processes of a brain within a computer.

Writes Marcus:

“Whether it meets its grand goal or not, the European project will certainly lead to a significant number of smaller scientific advances. If the U.S. doesn’t follow suit, we will lose our lead in neuroscience, and will likely be left playing catch-up in some of the biggest game-changing industries on the horizon, like human-level artificial intelligence and direct brain-computer interfaces–even though both fields originated in the United States.”

Brain teasers

Here are some other recent findings from brain research:

  • Of mice and men watching mice: Researchers at Stanford were able to follow the brain activity of mice in real time after lacing their brains with fluorescent proteins. They were able to watch which parts of their brains glowed as they ran around a cage.
  • Does that mean a bird can get a song stuck in its head?: And a team of scientists at Duke University found that birds that can sing and mimic sounds have genes in their brains that can turn on and off in ways similar to human brains.
  • She lights up a womb: For the first time, MRIs of developing human fetuses showed communication signals between different parts of their brains. Scientists at Wayne State University in Michigan hope their research will lead to early treatments for autism and ADHD.
  • Nothing yet, though, on how foot gets in mouth: Researchers at the University of California, San Francisco, had mapped the process of speech, laying out the neural network that makes it happen, from the nerves that control the jaws, lips and tongue to those that manipulate the larynx.
  • Talk about a protein boost: There’s a biological explanation for why women talk more than men. Studies have shown that women speak an average of 20,000 words a day, while men average about 7,000. According to a study published in the Journal of Neuroscience last week, it may be because they tend to have higher levels of a protein in their brain that’s been linked to verbal communication.

Video bonus: A BBC journalist gets a tour of the wiring on his own brain.

More from Smithsonian.com

A More Human Artificial Brain

Brain Science: 10 Studies That Get Inside Your Head




February 13, 2013

10 Fresh Looks at Love

valentine day love

Scientists are still wrestling with how love works. Photo courtesy of Flickr user Hamed Masoumi

It should probably tell us something that the most frequently asked question on Google last year was “What is love?” Clearly, most of us are clueless on the matter; otherwise we wouldn’t be turning to algorithms for an explanation.

Which explains why scientific research on love continues unabated. We want answers.

So, on the eve of Valentine’s Day, here are 10 recent studies or surveys trying to make sense of matters of the heart.

1) You light up my brain: Researchers at Brown University in Rhode Island say that based on brain scans, they may be able to predict if a relationship will last. The scientists did MRIs on 12 people who said they were passionately in love, then repeated the process three years later. In the six people whose relationships lasted, the scans showed that the part of the brain that produces emotional responses to visual beauty was particularly active when they were shown a picture of their partners. But those same six had lower levels of activity in the pleasure center of the brain tied to addiction when they looked at the photo.

2) Yeah, but what did it do for their sinuses?: Scientists continue to ponder the effect of oxytocin, the so-called “love hormone” produced by the pituitary gland. One of more recent studies, at the University of Zurich, found that while men generally withdraw during conflict with their mates, those who inhaled an oxytocin nasal spray smiled more, made eye contact and generally communicated better during disagreements.

3) What you see is what you don’t get: A new study by sociologist Elizabeth McClintock at the University of Notre Dame concluded that highly attractive women are more likely to seek exclusive relationships than purely sexual ones, and also that, for women, the number of sexual partners decreases as their physical attractiveness increases.

4) Okay, now let’s try a salsa beat: Meanwhile, at the University of California, Davis, scientists studying the physical behavior of couples in relationships found that when they were sitting near each other–but without speaking or touching–their breathing patterns and heartbeats often matched up. The researchers also discovered that the women tended to adjust their behavior to their partners more often.

5) So yes, putting the toilet seat down is an act of love: A professor at the University of Rochester who’s been studying newlywed couples for the past several years says members of married couples who do small acts of compassion and thoughtfulness for each other usually have happier relationships. Researchers Harry Reis also found that men more often said that they had put their partner’s wishes ahead of their own.

6) As they say in the relationships biz, it’s complicated: According to a study soon to be published in the journal Psychological Science, people like to believe that their way of life–whether they’re single or in a couple–is the best choice for everyone. The researchers also found that when it came to Valentine’s Day, people believed that their friends would be happier if they were in the same situation as they were–in other words, people in a couple thought their single friends would enjoy themselves more on Valentine’s Day if they were in a relationship, while singles thought their coupled friends would have a better time if they were single.

7) Thanks for not sharing: And apparently it’s not such a good idea to make big displays of affection on Facebook. So say researchers at the University of Kansas who discovered that people don’t like their partners sharing their feelings about their relationships with the Facebook universe. Participants in the study said they felt less intimacy with their partners if they went public with how they felt about their loved one.

8) Another reason not to do windows: Here’s one to stir up debate. According to a research team of American and Spanish scientists, men who share in the housework have sex with their wives less often than men in “traditional” marriages where the women handle all of the household chores. This runs counter to previous studies which concluded that married men had more sex in exchange for helping around the house. In the recent study, married couples reported having more sex if the women did the cooking, cleaning and shopping and the men did the gardening, electrics and plumbing, took car of the car and paid the bills.

9) Road trip!: A survey of more than 1,000 American adults found that couples that travel together have better sexual relationships than those that don’t. Almost two-thirds of those surveyed recently by the U.S. Travel Association said that a weekend vacation was more likely to spark up their relationship than a gift. And almost 30 percent said their sex life actually improved after traveling together.

10) Which is why you don’t take dogs on vacations: On the other hand, dogs may not be so good for your sex life. About 73 percent of dog owners who answered another survey said their pets get jealous when they show physical affection toward their partners. And it probably doesn’t help that almost as many of those surveyed said their dog sleeps with them in bed.

Video bonus: It’s really not that hard to write a bad love song. The Axis of Awesome lays it all out for you.

Also on Smithsonian.com

The Science of Love

Biology’s 10 Worst Love Stories




January 30, 2013

These Machines Will Be Able to Detect Smells Your Own Nose Cannot

cancer sniffing machine

A machine that sniffs out cancer. Photo courtesy of Metabolomx

Admittedly, it’s a little hard to imagine smell scientists, but research published earlier this week has those who study the sense of smell taking sides.

It comes down to how our noses detect odors. The long-standing explanation is that our noses have receptors that respond based on the shapes of odor molecules. Different molecules fit together with different receptors, the thinking goes, and when a match is made, the receptor tips off the brain that our nose has picked up a whiff of coffee or perhaps a very different smell emanating from the bottom of our shoe.

But a conflicting and more exotic theory received a boost in the new study by researchers in Greece. It holds that we can also sense smells through quantum physics, in this case the vibration of odor molecules. As Mark Anderson posits at Scientific American, “Does the nose, in other words, read off the chemical makeup of a mystery odorant—say, a waft of perfume or the aroma of wilted lettuce—by ‘ringing’ it like a bell?”

I know what you’re thinking: What difference does this make as long as I can still smell bacon?

Sniffing out trouble

But actually it does matter, because the more we understand the process of smelling, the more effective we can be at recreating it in machines. In fact, just last month IBM, in its annual “5 in 5″ forecast–a list of technologies it believes will hit the mainstream in five years–focused exclusively on the development of the five human senses in machines.

To mimic smelling, tiny sensors would be integrated into smartphones or other mobile devices and, as a breathalyzer can determine alcohol levels, they would gather data from the smell of your breath by detecting chemicals that humans wouldn’t perceive and send it to a computer in your doctor’s office. The thinking is that eventually this would be a core component of home health care–the ability to “smell” diseases remotely, such as liver or kidney ailments, asthma or diabetes.

Or on a more basic level, as IBM’s Hendrik Hamann put it: “Your phone might know you have a cold before you do.”

IBM is also working with health care organizations to equip patient and operating rooms with sensors that can help address one of the biggest problems hospitals face today–how do you keep them hygienic? Hundreds of sensors will basically sniff for cleanliness, identifying the chemical compounds that create odors, some of which are undetectable by humans. The staff can say they cleaned a room; the sensors will know if and when they did.

Every breath you take

The smell tests might even detect cancer. Last fall, in a study in the Journal of Thoracic Oncology, researchers from Israel and Colorado reported that breath analysis could distinguish between benign and malignant lung tumors with 88 percent accuracy. Plus, the breath test could determine the specific type and stage of the lung cancers.

And at the Cleveland Clinic, Dr. Peter Mazzone, director of the lung cancer program, is testing a sensor array that changes color when a patient’s breath passes over it. In a study of 229 patients, the test, using a machine developed by the California firm Metabolomx, was able to distinguish those with lung cancer with more than 80 percent accuracy.

Meanwhile, Mazzone and his team are collecting as many breath samples as possible from patients, both with and without lung cancer. The goal is match breath patterns with physical conditions. “My vision,” Mazzone told the Wall Street Journal, “is being able to say, ‘This is a 60-year old with emphysema who smoked for 30 years—what’s the chance of there being cancer there?’ But we have to teach the device what it looks like first.”

Or, perhaps more accurately, what it smells like.

Smell tests

Here are other recent discoveries scientists have made about smell:

  • Me, my smell and I: Research in Germany concluded that not only can we identify our own body odor, but that we prefer it. For the study, women were asked to select which of their armpit odors they liked more. They showed a clear preference for the one perfumed with a solution that included elements of their own scent.
  • Can robots wear Axe?: The U.S. Navy is looking to use scent-sniffing robots to move 1,000-pound bombs on ships. The idea is that a human would control the lead robot and it would dispense the equivalent of a robot pheromone that a swarm of other robots would follow like army ants.
  • I love the smell of gridlock in the morning: When people are anxious, their sense of smell becomes more acute, according to a recent study at the University of Wisconsin-Madison.
  • Why your dog can sniff out a chicken leg from a block away: And from the University of Chicago comes research finding that animals are able to focus their sense of smell much like humans can focus our eyes. Through their finely-honed sniffing techniques, they apparently can bring scents to receptors in different parts of the nose.
  • There’s the rub: And finally, a study in the U.K. has found that thanks to a genetic variation, two percent of the population never has underarm body odor. Yet more than three-quarters of them still use deodorant because, well, that’s what people do.

Video bonus: Stuart Firestein, chairman of the biology department at Columbia University, tells you all you want to know about how our nose does its job.

Video bonus bonus: A Chinese airline that checks out the armpit odors of people interviewing to be pilots.

More from Smithsonian.com

Design Scent: An Olfactory Exhibition at the Museum of Art and Design

We Can Only Process Thirty Smells at a Time



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