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for May, 2009.
Well, I usually choose my topic-of-the-week by which file is bulging the worst and this week is no exception. The medical file is just full of juicy stories about what ails us so off we go on another excursion in the wonderful world of medicine. We’ll start off with some things that are good for us.
GO FOR THE CURRY
Have you ever tried Indian food? Do you like curry? Well, it turns out that it’s good for you and you might want to eat some more of it. The spice turmeric is the main ingredient in curry powder and the active chemical in turmeric is curcumin. A recent study on curcumin by researchers at the Medical College of Georgia shows that it not only lowers your chances of getting cancer and Alzheimer’s disease, but may reduce the size of a hemorrhagic stroke.
The researchers are using animal models to study curcumin’s effect on intracerebral hemorrhages, bleeding in the brain caused by ruptured vessels. Patients with this type of stroke are often treated for symptoms – such as headache and nausea – with medications, but not the stroke itself. Invasive surgery to remove the clot is usually needed, but many of the patients who suffer this kind of stroke are not good candidates for surgery. About 17 percent of all strokes are hemorrhagic, according to the American Stroke Association, and they usually occur in people with high blood pressure.
The researchers discovered that curcumin significantly decreased the size of a blood clot but they remain unsure about why it does so. Curcumin is a potent anti-inflammatory and antioxidant.
Timing is critical for patients who often don’t know they have had a stroke and may not be seen by a physician for several hours. Stroke victims experience symptoms like seizures, vision or cognitive problems but sometimes they ignore the symptoms. Head injuries can also cause hemorrhagic bleeding. But treating the victims can become tricky after an hour or so.
Patients likely will need to get curcumin intravenously. The researchers believe it may also help prevent strokes; they intend to pursue this line of study with the idea of also making it available in a concentrated tablet form for those at-risk.
So next time you eat out choose an Indian restaurant. Or learn to make dynamite curry at home!
And now, a new benefit from one of the oldest drugs in the pharmacopoeia
AN ASPIRIN A DAY
Although I take my daily aspirin, I’m one of those people who bleeds a little more freely because of it. I was actually thinking about asking my doctor if I really need to take it because it doesn’t appear to make much difference with heart attacks in women. But apparently the heart isn’t the whole story for this ancient drug.
Simple aspirin may prevent liver damage in millions of people suffering from side effects of common drugs, alcohol abuse, and obesity-related liver disease, a new Yale University study suggests. The study documents that in mice, aspirin reduced mortality caused by Tylenols overdoses. It further showed that molecules known as TLR antagonists, which block receptors known to activate inflammation, have a similar effect as aspirin.
Since these agents seem to work by reducing injury-induced inflammation, the results suggest aspirin may help prevent and treat liver damage from a host of non-infectious causes like drugs and alcohol.
Aspirin and the TLR antagonists apparently block a central pathway responsible for liver injury caused by these factors. Many promising drugs have failed their clinical trials because they were toxic to the liver and they just might work if they were combined with aspirin.
And even though I don’t do drugs or alcohol, a healthy liver just might be worth putting up with the “Where did all this blood come from?” episodes a little longer.
I do take my daily aspirin, but for years I’ve defied the “Eat a healthy breakfast every day” because I don’t like most breakfast foods like eggs and cereal. But what I have done every day for many years is eat a Golden Delicious apple for breakfast. And it turns out I may have had the right idea all along.
An Apple a Day
Six studies published in the past year by a Cornell researcher add to growing evidence that an apple a day — as well as daily helpings of other fruits and vegetables — can help keep the breast-cancer doctor away.
In one of his recent papers, Rui Hai Liu, Cornell associate professor of food science, reports that fresh apple extracts significantly inhibited the size of mammary tumors in rats; and the more extracts they were given, the greater the inhibition.
“We not only observed that the treated animals had fewer tumors, but the tumors were smaller, less malignant and grew more slowly compared with the tumors in the untreated rats,” said Liu, pointing out that the study confirmed the findings of his preliminary study in rats published in 2007.
In his latest study, he found that a type of adenocarcinoma — a highly malignant tumor and the main cause of death of breast-cancer patients, as well as of animals with mammary cancer — was evident in 81 percent of tumors in the control animals. However, it developed in only 57 percent, 50 percent and 23 percent of the rats fed low, middle and high doses of apple extracts.
Liu found that phytochemicals (active chemicals produced by plants) called phenolics were the agents that were involved. Phenolics are mainly found in apple peel, so if you routinely peel your apples before eating them, you don’t get the benefits. Liu found that apples provide 33% of the phenolics that Americans consume annually.
Breast cancer is the most frequently diagnosed invasive cancer and the second leading cause of cancer deaths in women in the United States. Liu said that his studies add to the growing evidence that increased consumption of fruits and vegetables, including apples, would provide consumers with more phenolics, which are proving to have important health benefits. He encourages consumers to eat more and a wide variety of fruits and vegetables daily.
I certainly agree with him about the fruits and vegetables, but I did find one thing rather disconcerting about his study. The breast cancer developed in only 57 percent, 50 percent and 23 percent of the rats fed low, middle and high doses of apple extracts. These low, middle and high doses were the equivalent of one, three and six apples a day in humans. I like apples, but I’m not sure I’m ready to eat six a day!
Americans get about 33 percent of phenolics from apples. This chart from one of Liu’s recent papers shows the percentage of phenolics (phytochemicals) that Americans get from various fruits. (Credit: Image courtesy of Cornell University)
Well, we’ve had three positive stories that tell you to eat more curry, eat more apples and take your medicine. Now we’ll end on something that research says you should do less of.
EAT LESS MEAT
A new study has shown that people who eat more red meat and processed meat appear to have a modestly increased risk of death from all causes and also from cancer or heart disease over a 10-year period, according to a new article. In contrast, a higher intake of white meat appeared to be associated with a slightly decreased risk for overall death and cancer death.
Rashmi Sinha, Ph.D., and colleagues at the National Cancer Institute, Rockville, Md., assessed the association between meat intake and risk of death among more than 500,000 individuals who were part of the National Institutes of Health-AARP Diet and Health Study. Participants, who were between 50 and 71 years old when the study began in 1995, provided demographic information and completed a food frequency questionnaire to estimate their intake of white, red and processed meats. They were then followed for 10 years through Social Security Administration Death Master File and National Death Index databases.
During the follow-up period, 47,976 men and 23,276 women died. The one-fifth of men and women who ate the most red meat had a higher risk for overall death, death from heart disease and death from cancer than the one-fifth of men and women who ate the least red meat, as did the one-fifth of men and women who ate the most vs. the least amount of processed meat.
When comparing the one-fifth of participants who ate the most white meat to the one-fifth who ate the least white meat, those with high white meat intake had a slightly lower risk for total death, death from cancer and death from causes other than heart disease or cancer. The researchers say that 11 percent of deaths in men and 16 percent of deaths in women could have been prevented if the people had decreased their red meat consumption.
So why would eating meat cause you to die early? There are several reasons. Cancer-causing compounds are formed during high-temperature cooking of meat. Meat also is a major source of saturated fat, which has been associated with breast and colorectal cancer. In addition, lower meat intake has been linked to a reduction in risk factors for heart disease, including lower blood pressure and cholesterol levels.
Individuals who eat more red meat and processed meat appear to have a modestly increased risk of death from all causes and also from cancer or heart disease over a 10-year period, according to a new article. (Credit: iStockphoto/Ron Bailey)
Eat more, eat less. Just work at what keeps you healthy and you’ll live a lot longer.
Greetings everyone and welcome to another trip into the wonderful and sometimes kooky world of science. I looked at the files this week and discovered that the biggest one was the one labeled Miscellaneous so today’s topics are going to be all over the map. For our first one, I’ll take the Boomers on a little trip down Memory Lane
REMEMBERING TO THE MUSIC
Researchers have recently announced the results for the Magical Memory Tour, the largest-ever international online survey, which asked people to record their memories of the Beatles to create the biggest database of autobiographical memories ever attempted. The survey sought enhance our understanding of human memory by discovering the role The Beatles and their music play in our personal lives.
The six-month online survey generated some 3000 responses from people ranging from 17 to 87 years old and spanning 69 different nationalities. People were invited to share the most vivid memory that came to mind relating to a Beatles album, song, news story or band member. The majority of respondents were ‘silver surfers’, between the ages of 55 to 65, who would have been teenagers during the Beatles heydays in the 1960s.
As expected, the majority of memories related to the teenage years of people’s lives, showing a classic reminiscence bump. The difference is that the bump occurs slightly earlier in the lifespan than for autobiographical memories more generally, suggesting that music, or at least The Beatles’ music, is important in the storage of particularly early memories.
The song that emerged overall as generating the most memories was ‘She Loves You’, not surprising since this was the biggest selling single of the 60’s and the Beatles’ most popular record ever.
There were some differences among nationalities. English people related most memories to the song ‘She Loves You’, while for Americans it was ‘I Want to Hold Your Hand’. English people reported most film-associated memories to ‘Help’, while Australians reported most to ‘A Hard Day’s Night’. But what’s more interesting than these relatively minor differences between nationalities is the similarities in terms of the moods, feelings, scenes and situations they relay. They show the influence The Beatles had as global cultural icons.
One of the researchers said they were impressed with how vividly people recalled memories sometimes from more than 40 years ago, especially when many eloquent and vivid memories appear to have been little recalled in decades. This shows the power of music in shaping and reliving sometimes long-neglected memories.
The researchers also hoped to examine the levels of emotionality in the uploaded memories. They anticipated that women might have more emotional memories but that wasn’t substantiated by the data. Apparently the Beatles really were a universal force in people’s lives. To read memories from the survey visit http://www.magicalmemorytour.com.
And though the Beatles may be intimately linked with the memories and emotions of many of us, there’s some surprising research that says that some of the most basic parts of our makeup are not learned but are innate.
The result of a surprising new study says that our facial expressions of emotion are hardwired into our genes and are not products of cultural learning. The study is the first of its kind to demonstrate that sighted and blind individuals use the same facial expressions, producing the same facial muscle movements in response to specific emotional stimuli.
The study also provides new insight into how humans temper our emotional displays according to social context, suggesting that the ability to regulate emotional expressions is not learned through observation.
San Francisco State University Psychology Professor David Matsumoto compared the facial expressions of sighted and blind judo athletes at the 2004 Summer Olympics and Paralympic Games. More than 4,800 photographs were captured and analyzed, including images of athletes from 23 countries.
“The statistical correlation between the facial expressions of sighted and blind individuals was almost perfect,” Matsumoto said. “This suggests something genetically resident within us is the source of facial expressions of emotion.”
Matsumoto found that sighted and blind individuals manage their facial expressions of emotion in exactly the same way and they do it according to social context. For example, because of the social nature of the Olympic medal ceremonies, 85 percent of silver medallists who lost their medal matches produced “social smiles” during the ceremony. Social smiles use only the mouth muscles whereas true smiles, known as Duchenne smiles, cause the eyes to twinkle and narrow and the cheeks to rise.
The losers all produced these ‘social smiles’ whether they were blind or sighted. The athletes who were blind from birth couldn’t have learned to control their facial expressions in this way through visual learning so there has to be another mechanism. Dr. Matsumoto speculates that our emotions, and the systems to regulate them, are vestiges of our evolutionary ancestry. It’s possible that in response to negative emotions, humans have developed a system that closes the mouth so that they are prevented from yelling, biting or throwing insults.
So watch that ‘social smile’. You may just be responding to an age-old evolutionary beat!
Photos show comparison of facial expressions by blind and sighted athletes who just lost a match for a medal. (Credit: Bob Willingham)
Our next two items have to do with food, one of my favorite pastimes. Remember I told you last week about the fact that one of the world’s richest ecosystems is the one that lives in your personal gut? Well, not only do bacteria digest your food for you, it turns out they have a lot to do with which food you eat!
ENHANCING THE TASTE
Scientists in Switzerland have reported that bacteria in the human mouth play a role in creating the distinctive flavors of certain foods. They found that these bacteria actually produce food odors from odorless components of food, allowing people to fully savor fruits and vegetables.
The researchers point out that some fruits and vegetables release characteristic odors only after being swallowed. While scientists had previously reported that volatile compounds produced from precursors found in these foods are responsible for this ‘retro-aromatic’ effect, the details of this transformation were not understood.
To fill that knowledge gap, the Swiss scientists performed sensory tests on 30 trained panelists to evaluate the odor intensity of volatile compounds called ‘thiols’ that are released from odorless sulfur compounds found naturally in grapes, onions, and bell peppers.
When given samples of the odorless compounds, it took participants 20 to 30 seconds to perceive the aroma of the thiols – and this perception persisted for three minutes. The researchers also determined that the odorless compounds are transformed into the thiols by anaerobic bacteria residing in the mouth – causing the characteristic ‘retro-aromatic’ effect.
“The mouth acts as a reactor, adding another dimension to odor perceptions,” they explain. However, the authors conclude, it is saliva’s ability to trap these free thiols that helps modulate the long-lasting flavors.
So not only do bacteria digest your food for you, they tell you you like it and you want to eat it! And now we’ll move on to a tale of why you eat too much. This one probably has a lot of application here!
I’LL HAVE SOME OF THAT
Researchers at Cornell University have recently made a not-so-surprising discovery. Overweight diners at Chinese buffets serve themselves differently and eat differently than normal weight individuals. These differences may, in fact, lead them to overeat. Compared to normal weight diners, overweight individuals sat 16 feet closer to the buffet, faced the food, used larger plates, ate with forks instead of chopsticks, and served themselves immediately instead of browsing the buffet.
“What’s crazy is that these people are generally unaware of what they’re doing – they’re unaware of sitting closer, facing the food, chewing less, and so on,” says Brian Wanink, lead author of the study and of the book “Mindless Eating: Why We Eat More Than We Think.”
The study was published in the journal Obesity and includes observations of 213 diners at 11 all-you-can-eat Chinese restaurant buffets across the country. Study participants included a range of normal weight to obese diners, none of whom were Asian. Major study findings include:
- 27% of normal-weight patrons faced the buffet compared to 42% of obese diners.
- Overweight diners sat an average of 16 feet closer than normal-weight diners.
- 16% of obese diners sat at a booth rather than a table compared to 38% of normal weight diners
- 71% of normal-weight diners browsed the buffet before serving themselves compared to 33% of obese diners
- 24% of normal-weight people used chopsticks compared with 9% of overweight people
The researchers say that when food is more convenient people tend to eat more and that seemingly subtle differences in behavior and environment may cause people to overeat without even realizing it.
So, the next time you go to the buffet, see how many of the research criteria you meet and then have a look at your waistline. Correlation? Only you can say!
Last week we talked about life in some very strange places like in sinkholes at the bottom of lakes and in your own gut. But this week we’re going to talk about some even more exotic places. We’re going to move out into the solar system and examine the most likely places among our neighbors that may have life.
Back in January, I told you about the discovery of methane on Mars. Although it didn’t make a big splash in the news media (someone was inaugurated about the same time) it could conceivably be one of the biggest stories of the 21st century because free methane is vanishingly rare. Because it only has one carbon atom, methane combines with virtually everything and as far as we know, it can be produced by only two processes.
It can be produced by volcanic activity. Although we don’t see all the ash, dust and gas produced in volcanic eruptions, it is possible that there are underground reservoirs of methane on Mars that were produced long ago. Methane from these ‘tanks’ may be slowly seeping to the surface and producing the small amounts of methane in Mars’ atmosphere.
But the more intriguing possibility is that the methane on Mars was produced by life. As I said in January’s article, you produce methane every day of your life. It’s a common by-product of the bacterial metabolic processes that digest your food for you. Cows produce methane, your dog produces methane, it’s produced in abundance by teen-aged boys who find it a great source of humor. Everything that eats produces methane as a result of that eating. Methane production, in short, is a sign of LIFE.
So is it volcanism or life that’s producing the methane on Mars? Whatever the answer is, I’ll never be able to tell my Astronomy students again that Mars is a “dead world”. We still have working rovers on the surface of Mars and the satellites that orbit Mars see much more of the surface of that planet than the satellites of Earth see of home. So with all those robots to send us information, maybe next week or next year we’ll get our answer to the methane mystery on Mars.
Besides carbon, the other requirement for life-as-we-know-it is liquid water. Those underground bacteria could easily have access to water on Mars in the form of ice, which their internal heat could melt or there could be liquid water below the ice, just as there is in Antarctica.
Liquid water is a comparative rarity in the solar system. There’s literally tons of water, but most of it is ice. Until very recently the only place we knew of with lots of liquid water is Earth. But those roaming robots have shown us that there are at least three other places out there that probably have more liquid water than Earth; much more.
One of them is Europa, the ice moon that circles Jupiter. When we sent robots to orbit Jupiter, we discovered that Europa wobbles as it orbits Jupiter. You can tell if an egg is hard-boiled by spinning it. A hard-boiled egg is a solid body inside and it spins just like a top. A raw egg has liquid inside it and that liquid has two different densities. A raw egg won’t spin for very long; the sloshing liquid inside brings it to a quick halt.
The fact that Europa wobbles implies that there’s liquid inside. Since the surface of Europa is frozen water ice, the implication is that the inside of Europa is filled with liquid water with a rock core at the center. Europa probably has a liquid water ocean that’s around 20 miles deep. Europa is about the size of our moon and may contain more liquid water than the seas of Earth.
But the big boy of the ‘water’ scenario is Jupiter’s moon Ganymede. Ganymede is the largest moon in the solar system and it’s bigger than Mercury. Ganymede has its own magnetic field, which implies that it has an iron core like Earth and it also wobbles as it orbits Jupiter. If there is a liquid water ocean inside Ganymede, it could be as much as 300 MILES deep. Ganymede is probably the biggest reservoir of liquid water in the solar system.
But notice that we say ‘maybe’ and ‘probably’ and ‘could be’. We speculate about liquid water in the moons of Jupiter (and that also includes the last Galilean satellite, Callisto) but there is a moon in the solar system about which all speculation about a liquid ocean has ceased. And that’s Saturn’s moon, Enceladus.
We have a robot called Cassini in orbit around the planet Saturn and it’s discovered something very interesting about Enceladus, the brightest little moon in the solar system. We’ve known for a long time that its surface had to be made of something very reflective. The surface of Enceladus is solidly frozen water ice and it’s as reflective as new-fallen snow. And Enceladus also wobbles as it goes around Saturn.
Then Cassini found something really interesting. There were what the team called ‘tiger stripes’ at Cassini’s south pole. A closer look during one of Cassini’s scheduled fly-bys of Enceladus revealed these ‘tiger stripes’ were huge cracks in the ice.
Then they discovered something REALLY interesting. Liquid water is erupting from these cracks. We don’t have to infer from the wobble that Enceladus contains liquid water, we KNOW it does. And not only is it erupting liquid water, there are also organic chemicals in the water.
The ‘tiger stripes’ on Saturn’s ice moon Enceladus. (Credit: NASA/JPL/Space Science Institute)
Could microbial life exist inside Enceladus, where no sunlight reaches, photosynthesis is impossible and no oxygen is available? To answer that question, we need look no farther than our own planet to find examples of the types of exotic ecosystems that could make life possible on Saturn’s geyser moon. The answer appears to be, yes, it could be possible.
In recent years, we’ve found life on Earth that thrives in places where the sun doesn’t shine and there’s no oxygen because no photosynthesis takes place there. Microbes have been discovered that use the energy from chemical reactions between different kinds of minerals, and others that live off the energy from naturally-occurring radioactive decay.
There are at least three ecosystems found on Earth that harbor the kind of life that could survive in the sunless seas of Enceladus. Two are based on methanogens (hmmm, this is fancy Latin for ‘methane generator!), very primitive bacteria relatives that thrive in harsh environments without oxygen. Deep volcanic rocks along the Columbia River and in Idaho Falls host two of these ecosystems, which get their energy from chemical interactions. The third ecosystem is powered by the energy produced by natural radioactive decay, and was found deep below the surface in a mine in South Africa.
So the evidence points to the feasibility of life in Enceladus. But how would it get its start? A major problem in answering that question is that we don’t know how life originated on Earth, nor have we been able to reproduce Earth’s first spark of life in the laboratory. But here’s the good news: there are a lot of theories for how life originated on Earth. Now the question is — do they apply to Enceladus?
Two theories for the origin of life on Earth do seem to apply to Enceladus–the "primordial soup" theory and the “deep-sea vent” theory.
Primordial Soup Theory
Charles Darwin first proposed that life originated in a soup of organic material created from non-biological sources. The possibility that this is exactly what happened was demonstrated in a famous expe
riment in 1953 when the chemists Stanley L. Miller and Harold C. Urey cooked up a primordial soup of chemicals thought to have been present on early Earth before life began. A spark, simulating lightning, was passed through this highly reduced mixture of methane, ammonia, water vapor and hydrogen. Within two weeks, a few amino acids, some of the building blocks of life, had formed in the soup. While Miller and Urey did not actually create life, they demonstrated that very complex molecules like amino-acids could spontaneously assemble from simpler chemicals.
(The actual ‘gunk’ created in the Miller-Urey experiments has been recently examined using new techniques. This also included an experiment Dr. Miller performed that introduced steam into the experiment. In his 1953 paper, Dr. Miller had reported that he had detected five amino acids produced by the original apparatus. The recent examination found small amounts of nine additional amino acids in those samples. In the residues from the apparatus with the steam injector, the scientists detected 22 amino acids, including 10 that had never before been identified from the Miller-Urey experiment.)
So where did this organic soup come from? Here on Earth, it’s possible that all the ingredients were already in place. Another theory is that the right soup mix ingredients arrived as incoming comet material and interplanetary dust.
Deep Sea Vent Theory
The deep-sea vent theory for the origin of life on Earth might apply to Enceladus as well. In this scenario, life on Earth began at the interface where chemically rich fluids, heated by tidal or other mechanisms, erupted from the sea floor into the existing ocean. Chemical energy is derived when reduced gases, like hydrogen-sulfide and hydrogen emerge from the vent and contact an oxidant, like carbon dioxide. Hot spots like this could also occur on the sea floor of Enceladus.
We don’t know how long it takes for life to start when the ingredients are there and the environment is suitable, but it appears to have happened quickly on Earth. It could have happened just as quickly on Enceladus.
For life to persist once it has been established requires an environment of liquid water, the essential elements and nutrients, and an energy source. Enceladus has liquid water and both simple and complex organic chemicals. Some kind of energy source is producing the erupting geysers. Hmmmm, liquid water, organic chemicals and an energy source.
As a scientist said who studies the moon Europa: “Do you really think you can have a liquid water ocean for five billion years and NOT have life in it?”
Are we alone? More and more evidence is giving us the answer “Probably not!”
About two miles below the ground in a South African gold mine, scientist Duane Moser stands next to the fracture zone (white area) where he and Li-Hung Lin found bacteria that live in an ecosystem driven by radioactive decay with no oxygen, no light and no organic input. (Credit: Photo by Li-Hung Lin. Image courtesy of NASA)
Cruise on over to the Deep Website at www.thedeepradioshow.com to learn more about life in other places and many other topics. Enjoy!
Jim is, above all, a passionate eco-humanitarian who has developed his own science talk-radio show to inform The DEEP’s listeners about such newsy topics as global warming, shark-finning and reef protection as well as to explore earth’s many underwater and space mysteries.
sailing 12,000 miles and visiting five countries Jim is back here, ready to explore the depths of the ocean to the deepest frontier, space MORE>>
Lady Pam Eastlick is an expert in both the stars
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