IT’S ALL IN YOUR HEAD . . . ER . . . STOMACH?

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

I thought I’d delve into the medical file and I found two stories that have more to do with the health of our heads than our bodies. Have you noticed when you’re surfing the web that a lot of people sure think that everybody else is out to get them? Yes, I know even paranoiacs have enemies, but research conducted at the University of Kent in England has shown that people are more likely to believe conspiracy theories if they are willing to conspire.

The title of the paper, published in the British Journal of Social Psychology was Does it take one to know one? and it looked at the responses of 250 undergraduates to 17 alleged conspiracies, like the ‘assassinations’ of Princess Diana and John F. Kennedy, the ‘faking’ of the moon landings and the ‘orchestration’ of the 9/11 attacks by the US government.

In the first study, participants were asked if they would participate in such conspiracies, if they were in a position to do so. The scientists discovered that when participants indicated a willingness to conspire, they usually found the same conspiracy theories to be plausible, interesting, and worth considering.

In the second study, half of the participants were asked to remember a time when they helped someone. The research team thought this would make people realize that they were moral people. When these participants were compared to a control group, they were less willing to conspire, and as a result, were less likely to take conspiracy theories seriously.

So I guess the bottom line is “If you’d do it yourself, you probably believe it happened.”

But researchers at McMaster University have uncovered something really mind boggling. You may not have any control over how you feel about conspiracy theories and a lot of other stuff because that ecosystem you harbor in your gut just may be doing your thinking for you. For the first time, scientists have conclusive evidence that the bacteria living in YOUR gut influence both brain chemistry and behavior!

The findings are important because several common gut diseases, like irritable bowel syndrome, are frequently associated with anxiety or depression. There’s also speculation that some psychiatric disorders, like late onset autism, are associated with abnormal gut bacteria.

Your gut is home to over a trillion bacteria. Most of the time we live in harmony with our microscopic ecosystem and they perform a number of functions vital to health. They digest much of your food for you; they protect against infections and provide nutrition for your gut cells.

The researchers worked with healthy adult mice and showed that disrupting the normal bacterial content of the gut with antibiotics produced changes in behavior. The mice became less cautious or anxious. This change was accompanied by an increase in a brain chemical that’s been linked to depression and anxiety. When the antibiotics were stopped, the gut bacteria returned to normal and so did the brain chemistry and behavior patterns of the mice.

In another experiment, the researchers colonized germ-free mice with bacteria taken from mice with a different behavioral pattern. They found that when germ-free mice with a genetic background associated with passive behavior were colonized with bacteria from mice with higher exploratory behavior, the germ-free mice became more active and daring. Similarly, normally active mice became more passive after receiving bacteria from mice whose genetic background was associated with passive behavior.

Feeling anxious? Aggressive? Depressed? Just take this pill containing a live bacterial culture and we can fix that! Scary, eh?

PLAGUES

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

Greetings everyone. Well, it’s been a while since we dipped into the medicine file and I found a little history and some good news for us here in the tropics. Read on!

We’ve all heard about The Black Death also simply called ‘the plague’. This scourge that raged across Europe in the Middle Ages and killed millions of people was thought to have been caused by a bacterium called Yersinia pestis.

The epidemic’s actual cause has always been highly controversial and many other diseases have been considered. Now German researchers have used DNA and protein analyses from the skeletons of plague victims to conclusively show that Yersinia pestis was indeed, responsible for the Black Death in the 14th century and the subsequent epidemics that continued to ravage Europe and England for the next 400 years.

The skeletons were exhumed from mass graves in England, France, Germany, Italy, and the Netherlands. While other infections like leprosy can be easily identified long after death by the deformed bones, plague victims die almost immediately and the disease leaves no visible trace.

The team looked for traces of Y. pestis DNA in dental pulp and found it in all the skeletons. Once the Y. pestis infection was conclusively proven, the researchers tested to see which of the two modern forms of plague were present. They discovered two unknown forms, which are distinctly different from the modern pathogens. One of these two types probably no longer exists today. The other is similar to types that were recently isolated in Asia.

Plague is endemic in the American southwest and I’ve been waiting for the rats of Los Angeles to trigger a new epidemic. Once it goes pneumonic, the form that doesn’t depend on rats and fleas but can be transmitted directly from human to human, our modern day jets will transport it all over the world and the Black Death will walk again. There’s still no cure, you know.

And if the Black Death doesn’t scare you, there’s always malaria. But there may be good news on that front. Imagine an insect repellant that’s thousands of times more effective than DEET — the active ingredient in most commercial mosquito repellants – and also works against all types of insects, including flies, moths and ants.

Researchers at Vanderbilt University have discovered a new class of insect repellant based on insights about the basic nature of the sense of smell in mosquitoes and other insects. An insect smells with its antennae and until recently biologists thought an insect’s olfactory system worked the same way as it does in mammals. Proteins called odorant receptors, or ORs, sit on the surface of nerve cells in mammalian noses. When these receptors come into contact with smelly molecules, they trigger the nerves and signal the detection of specific odors.

Scientists have recently learned that an insect’s olfactory system doesn’t work that way. In the insect system, ORs don’t act alone. They form a complex with a unique co-receptor (called an Orco) that’s also required to detect smelly molecules. Insect ORs are spread all over the antennae and each responds to a different odor. Each OR must be connected to its co-receptor.

The Orco acts as the switch that tells the brain when there’s a signal. When a mosquito smells a specific odor, only the OR’s for that smell are turned on. If you can find a way to turn on all the Orcos, it effectively overloads the mosquito’s sense of smell and shuts down her ability to find blood.

Preventing a mosquito from smelling my blood is a fine thing, but here’s what I really love about this story.

"It wasn’t something we set out to find," said David Rinker, a graduate student who aided in the study. "It was an anomaly that we noticed in our tests."

And that, ladies and gentlemen is where a lot of real science happens. Not with the multimillion dollar research grants but when someone says “Hmmmm, that’s funny . . . . “

YOU ARE WHAT YOU EAT

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

I dipped into the medical file this week and discovered some good news and bad news about the food we all eat. Let’s get the bad news out of the way first.

Are you constantly craving McDonalds? Twinkies? Potato chips? Well a new research report suggests there’s someone you can blame. Your mother. The findings of the study suggest that pregnant mothers who eat high sugar and high fat diets have babies who are likely to become junk food junkies themselves. This happens because the high fat and high sugar diet changes the fetal brain’s reward pathways which changes food preferences.

The researchers studied two groups of pregnant rats that were fed either standard "rat chow" or a junk food diet made up of a selection of common human foods high in fat and high in sugar. After the baby rats were weaned, the pups from both groups were allowed to select their own diets from either the same range of junk food or standard rat chow. The researchers also measured the levels of "feel good" chemicals (dopamine and opioids) and the receptors acted on by these chemicals.

The scientists found that the rats whose mothers ate the junk food diet had higher levels of opioid receptors after they were weaned. This group also chose to eat more fatty foods as compared to the pups whose mothers ate the standard rat chow. This suggests that babies whose mothers eat excessive amounts of high-fat, high-sugar junk foods when pregnant or breastfeeding are likely to have a greater preference for these foods later in life.

Not only does this research help explain the ever-increasing rate of human obesity, it may also explain why some people easily resist fatty and sugary foods, while others seem hopelessly addicted.

It’s ironic somehow that the same mother who nagged you to eat your fruits and veggies may have caused your preference for junk food. I hope this convinces all you pregnant women who read this to go heavier on the green vegetables and a little lighter on the ice cream and Twinkies!

And in the light of junk food, recent research has found that there’s a vast difference in the health of the types of meat you eat. If given the choice between eating a hot dog or enjoying some BBQ chicken, consider the hot dog.

That’s because hot dogs, as well as pepperoni and deli meats, are relatively free of carcinogenic compounds but it’s a not a happy ending for bacon and rotisserie chicken — especially chicken skin — because both have higher levels of cancerous material.

The researchers studied ready-to-eat meat products to determine their levels of heterocyclic amines, or HCAs. These carcinogenic compounds are found in meat that’s fried, grilled or cooked at high temperatures. Studies have shown that humans who consume large amounts of HCAs have increased risk of stomach, colon and breast cancers.

The study focused on eight types of ready-to-eat meat products: beef hot dogs, beef-pork-turkey hot dogs, deli roast beef, deli ham, deli turkey, fully cooked bacon, pepperoni and rotisserie chicken. The researchers heated up the hot dogs and bacon in a microwave, cooked the pepperoni on a pizza either in the oven or a microwave and used the chicken and deli meat as obtained. After doing so, they studied the meat to determine whether it contained five different types of HCAs.

Pepperoni had the least HCA content, followed by hot dogs and deli meat. Fully cooked bacon and the rotisserie chicken contained all five types of HCAs. Rotisserie chicken skin had significantly higher HCA levels, with eight times as much as the other products. That’s because chicken skin contains more fat and protein and less moisture, and HCA levels tend to increase as moisture decreases.

So, you want a healthier life for you and your children? Stop eating so much junk food and stop eating chicken skin!

GOOD MEDS

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

After two weeks of global warming news I decided it was time to delve into the medical file. And since the global warming news is pretty dismal, I decided to feature some good news for a change.

Having a nice tan is always a beauty plus. But too much sun exposure carries a terrible price; skin cancer. Now, new research from England says that you can get that marvelous healthy tan without all that ultraviolet. All you have to do is . . . eat your vegetables?

Dr. Ian Stephen from the University of Nottingham and his team discovered that people who eat a lot of fruit and vegetables every day have a more golden skin color, thanks to substances called carotenoids. Carotenoids are responsible for the red coloring in fruit and vegetables like carrots and tomatoes, and are important for our immune and reproductive systems.

The researchers also discovered that when people were given the choice between the skin color caused by tanning and the skin color caused by carotenoids they preferred the color produced by carotenoids.

While the research of this particular study was conducted using Caucasian subjects, the paper also describes a study that suggests the effect may exist cross culturally, since similar preferences for skin color were found in an African population.

So if you want your skin to have an attractive color, don’t lie out in the sun, eat a healthy diet with plenty of fruit and vegetables.

The face in the middle shows the woman’s natural color. The face on the left shows the effect of sun tanning, while the face on the right shows the effect of eating more carotenoids. Participants thought the carotenoid color looked healthier. (Credit: Image courtesy of University of Nottingham)

And now a story that has profound implications for all of us and I can only hope it’s true.

Researchers at Stony Brook University have developed a powerful new painkiller that (so far) has no apparent side effects or addictive qualities. And this painkiller interacts with the body in a way that’s totally unlike any other painkiller in use today.

When a patient is given an opiate like morphine, the pain signals are still transmitted to the brain. The morphine alters how the brain perceives the pain but opiates also impair judgment and lead to drug dependence. This was brought home to me years ago when I sprained my ankle. I don’t remember what they gave me, but my leg still hurt dreadfully. I just didn’t care anymore.

The Stony Brook professors identified a sodium ion channel that’s involved in the transmission of pain and then produced a drug that blocks that specific channel. When this channel is blocked, the pain signals aren’t transmitted, even by the sensory nerves. And since the central nervous system is taken out of the equation, there are no side effects and no addictive qualities.

The potential for such a drug is enormous — the reduction or elimination of pain for patients with cancer, arthritis, migraine headaches, muscle pain, pain from burns, and pain from other debilitating diseases.

Drugs that block this channel in both pill and ointment forms are currently in Phase II clinical trials in England and Canada. The Research Foundation of the State University of New York is the holder of the various patents originating from the work of the Stony Brook researchers. Icagen Inc., now in partnership with Pfizer, holds the exclusive license to these patents and has announced their own drug has now entered Phase I clinical trials in the U.S.

Pain is important and we experience it for a reason. But once it’s told us there’s a problem, it’s time for it to make a quiet exit. Here’s hoping this really works!

CHEMICAL TRACERS

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

So, that bag of spinach you just took out of the fridge has been in there for a while. Is it still safe to eat? Would you like a spinach bag that changed color when harmful levels of bacteria were present? How about a device that could be implanted in your body that would monitor the sugar levels in your blood without those twice-daily finger pricks? It may sound like science fiction but researchers at Tufts University are designing such devices out of . . . silk.

Current optical devices are based primarily on glass, semiconductors and plastics. But the harsh solvents and extreme temperatures needed to make them make it impossible to incorporate bioactive sensing components into the devices. Chemical residues and lack of biodegradability also limit environmental and medical applications. Furthermore, biological components typically need to be stored at controlled temperatures to retain their activity.

Silk proteins are a natural for integrating optical and biological functions. They can be processed in water at ordinary temperatures and patterned to generate a wide range of optical elements, including ultrathin films, thick films, and tiny and large-diameter fibers. Silk proteins also offer excellent surface quality and transparency, which are necessary for high-quality optics. And equally important, they’re mechanically robust.

To make their devices, Tufts scientists boiled silkworm cocoons in water to extract the glue-like sericin proteins. The purified silk protein solution was poured onto holographic diffraction gratings with spacing as fine as 3600 grooves/mm. The cast silk solution was air dried to create solid silk films that were cured in water, dried and optically evaluated. A similar process was used to create lenses, microlens arrays and holograms.

Since the films are made at room temperature, any included biological receptors stay active after the solution has hardened into the film. The Tufts team embedded three very different biological agents in their silk solution: a protein (hemoglobin), an enzyme (horseradish peroxidase) and an organic pH indicator (phenol red). All three agents maintained their activity for long periods when the silk film was simply stored on a shelf. According to the Tufts researchers, this is truly amazing when you consider that the enzyme becomes inactive if left unrefrigerated for a few days. The researchers also discovered they could alter how light travels through the silk film with certain chemicals to create an optical signal for different kinds of biological activity.

Silk optics has captured the interest of the Defense Department, which has funded and been instrumental in enabling rapid progress of the research. If the military is interested, you can be sure that more advances are coming in this area. Silk rules!!

And in case you were planning on going on a crime spree in the mainland and then coming back here to the Marianas to hide, you might want to reconsider. Recent research has shown that the beverages you drink can be used to track your location through time.

The body removes hydrogen and oxygen atoms from the water and beverages you drink and uses them to make proteins, including the protein in hair. The proportions of the isotopes in hydrogen and oxygen vary geographically with higher values in low-latitude, low-elevation, or coastal regions, for instance, and lower values elsewhere.

The finding may help trace the origin of drinks or help criminal investigators identify the geographic travels of crime suspects and other individuals through analysis of hair strands.