Science-live

New Polymeric Car Paint Can Self-Heal Major Scratches, Dings

2011-05-23T08:57:00.000-07:00

New coating is ready for commercial applications

A major emerging field of materials science is to formulate new materials which, like living organisms, can self heal from macroscopic or microscopic damage. An international team of researchers has created a new kind of coating that could form the basis of true self-healing car paints.

Nissan implemented a primitive form of self-healing car paint in its EX and G lines, but the actual real world results of that endeavor have been mixed.

This new effort is comprised of teams from Case Western Reserve University in Cleveland, Ohio, led by Stuart J. Rowan; the Adolphe Merkle Institute of the University of Fribourg in Switzerland, led by Christoph Weder; and the U.S. Army Research Laboratory at Aberdeen Proving Ground in Maryland, led by Rick Beyer.

They have created a new self-healing coating that could be used as the basis of paint. The coating is formed via a technique called supramolecular assembly. Whereas usual polymers are single large molecules with thousands of atoms, the special new coating is an ionic polymer composed of metal ions and smaller polymeric molecules. The metal ions act as ”glue", linking the smaller molecules together to form chains.

The polymer's special character shows up when you expose it to UV light. The polymer enters a "molten" state, filling gaps and scratches. It then resolidifies.

Stuart Rowan, a professor of macromolecular engineering and science and director of the Institute for Advanced Materials at Case Western Reserve University, describes, "These polymers have a Napoleon Complex. In reality they're pretty small but are designed to behave like they're big by taking advantage of specific weak molecular interactions."

Researchers created large scratches and dings on the test coat, then shined a UV light on it, locally. The material "healed" itself in seconds. And unlike the self-healing found in living creatures, the material exhibited the ability to go through numerous scratching/healing cycles in a brief time without a loss of integrity.

The researchers evaluated a number of metal ion polymers before picking their current target. They found that mechanical properties (strength, flexibility without breaking, etc.) increased as the order of the resulting polymer increased. But as the mechanical strength increased, the ability to be healed decreased. So scientists opted for a moderate polymer with decent healing and mechanical traits.

As we discussed in our previous piece on self-healing plastics, microcracks -- microscopic scratches or cracks -- ultimately lead to big damage over time. Aside from resisting macroscopic scratches, the materials could undergo periodic treatments with the UV lamp to prevent wear from microcracks as well.

The research team feels the coating is ready for prime time. Professor Rowan says the next step is commercialization, stating, "One of our next steps is to use the concepts we have shown here to design a coating that would be more applicable in an industrial setting."

The study on the work was published in the journal Nature, perhaps science's most prestigious journal.

The work was funded by the Army Research Office of the U.S. Army Research Laboratory, the U.S. National Science Foundation, and the Adolphe Merkle Foundation.

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Divers Attempt to Communicate With Wild Dolphins, Using A Two-Way Translation Device

2011-05-22T14:49:00.000-07:00

Dolphins can understand more than 100 words, decipher human instructions and even use iPads to learn basic communication skills. But that’s kind of unfair on the part of us humans, don’t you think? Shouldn’t dolphins be able to ask for more smelt without learning our sign language or using our gadgets?
A researcher in Florida aims to meet the mammals in the middle, creating a new language that both humans and dolphins can understand.
Denise Herzing, founder of the Wild Dolphin Project in Jupiter, Fla., and Thad Starner, an artificial intelligence researcher at Georgia Tech, developed a project called Cetacean Hearing and Telemetry (CHAT). Researchers will test a prototype device this summer, reports New Scientist.
It involves a small computer encased in a waterproof shell and two hydrophones capable of detecting the full frequency of dolphin sounds, which can be up to 10 times higher than the highest pitch a person can hear. A diver will strap the computer to his or her chest, using a handheld device to select which sound to make in reply.
The diver will wear a mask with LED lights that indicate where the sounds are coming from, so he or she will know which dolphin is talking.
The team hopes to create a new language using a call-and-response method. Divers will play one of eight sounds they’ve already created, which correspond to dolphin desires like “play with seaweed” or “ride the boat’s wake.” Using CHAT software, the diver will determine whether the dolphin repeats the sound. Over time, the system will learn to recognize the dolphins’ accent, as it were, and learn how to decipher natural dolphin sounds.
Ultimately, the goal is to serve as a sort of Rosetta stone for dolphins, deciphering the fundamental units of dolphin language.
Herzing has been trying two-way communication with wild dolphins since 1998, and has successfully taught animals to associate symbols with specific requests, like “play with seaweed.” But the system wasn’t very dolphin-friendly, she tells New Scientist. The CHAT system will ideally play to the strengths of both dolphins and humans, allowing people to make dolphin-like communications that are more appealing to the cetaceans. And then they can tell us what they really think of those aquarium attractions.

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New Image Is Worth 1,235 Potential Alien Planets

2011-04-05T13:32:00.000-07:00

A photo may be worth 1,000 words, but a new depiction of NASA's Kepler mission is worth 1,235 potential alien planets. Created by a devoted mission scientist, the image takes stock of the Kepler observatory's prolific planet-hunting results so far.
The illustration shows all of Kepler's candidate planets — which await confirmation by follow-up observations — crossing the face of their host stars. This provides scale, and it's also a nod to Kepler's planet-hunting strategy: The spacecraft detects alien worlds by measuring the telltale dips in a star's brightness that occur during these planetary "transits."
The graphic is the brainchild of scientist Jason Rowe, who created it in an attempt convey Kepler's exoplanet discoveries to the masses in a clear, concise manner.
"The graphic itself has been great to show to people. There is lots of interesting astrophysics that one can present," Rowe, a member of the Kepler team at NASA's Ames Research Center and the SETI (Search for Extraterrestrial Intelligence) Institute, told SPACE.com. "My favorite one so far is that planets can be just as big as some of the smallest stars."
In Rowe's graphic, the parent stars of Kepler's potential alien worlds are arranged by size, with the largest at the top left of the diagram and the smallest at the bottom right. For reference, our own sun is shown sitting by itself, just beneath the top row. Both Jupiter and Earth are depicted transiting the sun in the illustration, researchers said.
To create the graphic, Rowe wrote a program with scientific plotting software, creating synthetic stellar images that were properly scaled to one another.
NASA launched the $600 million Kepler observatory in March 2009 to seek out planets circling alien stars.
To do that, the spacecraft is staring continuously at a single patch of the sky, watching for tiny changes in the amount of light coming from every star it sees. Astronomers use other telescopes to follow up Kepler's findings in order to confirm whether or not the candidate stars do, in fact, host exoplanets.
To date, Kepler has discovered 1,235 possible planets, with 54 of those candidates located within the so-called "Goldilocks zone" — that just-right range of distances around a star in which liquid water could exist on a planet's surface.
Based on the amazing wealth of planet candidates from Kepler, astronomers have estimated that our Milky Way galaxy could hold as many as 50 billion alien planets, with 2 billion of those perhaps being

Top 10 Most Venomous Snakes

2011-04-04T04:53:00.000-07:00

Rattlesnake

The only snake from the Americas on the list, the Rattlesnake is easily identifiable by the tell tale rattle on the end of its tail. They are actually a part of the Pit Viper family, and are capable of striking at up to 2/3rd their body length. The Eastern Diamondback in considered the most venomous species in North America. Surprisingly, juveniles are considered more dangerous than adults, due to their inability to control the amount of venom injected. Most species of rattlesnakes have hemotoxic venom, destroying tissue, degenerating organs and causing coagulopathy (disrupted blood clotting). Some degree of permanent scarring is very likely in the event of a venomous bite, even with prompt, effective treatment, and can lead to the loss of a limb or death. Difficulty breathing, paralysis, drooling and massive hemorrhaging are also common symptoms. Thus, a rattlesnake bite is always a potentially fatal injury. Untreated rattlesnake bites, especially from larger species, are very often fatal. However, antivenin, when applied in time, reduces the death rate to less than 4%

Death Adder

The appropriately named Death Adder is found in Australia and New Guinea. They actually hunt and kill other snakes, including some on this list, usually via ambush. Death Adders look quite similar to vipers, in that they have triangular shaped heads and short, squat bodies. They typically inject around 40-100mg of venom with an LD of 0.4mg-0.5mg/kg. An untreated Death Adder bite is one of the most dangerous in the world. The venom is a neurotoxin. A bite causes paralysis and can cause death within 6 hours, due to respiratory failure. Symptoms generally peak within 24-48 hours. Antivenin is very successful in treating a bite from a Death Adder, particularly due to the relatively slow progression of symptoms, but before its development, a Death Adder bite had a fatality rate of 50%. With the quickest strike in the world, a Death Adder can go from strike position to striking and back again within 0.13 of a second.

Vipers

Vipers are found throughout most of the world, but arguably the most venomous is the Saw Scaled Viper and the Chain Viper, found primarily in the Middle East and Central Asia, particularly India, China and South East Asia. Vipers are quick tempered and generally nocturnal, often active after rains. They are also very fast. Most of these species have venom that cause symptoms that begin with pain at the site of the bite, immediately followed by swelling of the affected extremity. Bleeding is a common symptom, especially from the gums. There is a drop in blood pressure and the heart rate falls. Blistering occurs at the site of the bite, developing along the affected limb in severe cases. Necrosis is usually superficial and limited to the muscles near the bite, but may be severe in extreme cases. Vomiting and facial swelling occurs in about one-third of all cases. Severe pain may last for 2-4 weeks. Often, local swelling peaks within 48-72 hours, involving the affected limb. Discoloration may occur throughout the swollen area as red blood cells and plasma leak into muscle tissue. Death from septicaemia, respiratory or cardiac failure may occur 1 to 14 days post-bite, or even later.

Philippine Cobra

Most species of Cobra would not make this list; however the Philippine Cobra is the exception. Drop for drop, its venom is the most deadly of all the Cobra species, and they are capable of spitting it up to 3 metres. The venom is a neurotoxin which affects cardiac and respiratory function, and can cause neurotoxicity, respiratory paralysis and death in thirty minutes. The bite causes only minimal tissue damage. The neurotoxins interrupt the transmission of nerve signals by binding to the neuro-muscular junctions near the muscles. The symptoms might include headache, nausea, vomiting, abdominal pain, diarrhea, dizziness, collapse and convulsions.

Tiger Snake

Found in Australia, the Tiger snake has a very potent neurotoxic venom. Death from a bite can occur within 30 minutes, but usually takes 6-24 hours. Prior to the development of antivenin, the fatality rate from Tiger snakes was 60-70%. Symptoms can include localized pain in the foot and neck region, tingling, numbness and sweating, followed by a fairly rapid onset of breathing difficulties and paralysis. The Tiger snake will generally flee if encountered, but can become aggressive when cornered. It strikes with unerring accuracy.

Black Mamba

The feared Black Mamba is found throughout many parts of the African continent. They are known to be highly aggressive, and strike with deadly precision. They are also the fastest land snake in the world, capable of reaching speeds of up to 20km/h. These fearsome snakes can strike up to 12 times in a row. A single bite is capable of killing anywhere from 10-25 adults. The venom is a fast acting neurotoxin. Its bite delivers about 100–120 mg of venom, on average; however, it can deliver up to 400 mg. If the venom reaches a vein, 0.25 mg/kg is sufficient to kill a human in 50% of cases. The initial symptom of the bite is local pain in the bite area, although not as severe as snakes with hemotoxins. The victim then experiences a tingling sensation in the mouth and extremities, double vision, tunnel vision, severe confusion, fever, excessive salivation (including foaming of the mouth and nose) and pronounced ataxia (lack of muscle control). If the victim does not receive medical attention, symptoms rapidly progress to severe abdominal pain, nausea and vomiting, pallor, shock, nephrotoxicity, cardio toxicity and paralysis. Eventually, the victim experiences convulsions, respiratory arrest, coma and then death. Without antivenin, the mortality rate is nearly 100%, among the highest of all venomous snakes. Depending on the nature of the bite, death can result at any time between 15 minutes and 3 hours.

Taipan

Another entry from Australia, the venom in a Taipan is strong enough to kill up to 12,000 guinea pigs. The venom clots the victim’s blood, blocking arteries or veins. It is also highly neurotoxic. Before the advent of an antivenin, there are no known survivors of a Taipan bite, and death typically occurs within an hour. Even with successful administration of antivenin, most victims will have an extensive stay in intensive care. It has been likened to the African Black Mamba in morphology, ecology and behavior.

Blue Krait

The Malayan or Blue Krait is, by far, the most deadly of this species. Found throughout South East Asia and Indonesia, 50% of bites from the deadly Blue Krait are fatal, even with the administration of antivenin. Kraits hunt and kill other snakes, even cannibalizing other Kraits. They are a nocturnal breed, and are more aggressive under the cover of darkness. However, overall they are quite timid and will often attempt to hide rather than fight. The venom is a neurotoxin, 16 times more potent than that of a Cobra. It quickly induces muscle paralysis by preventing the ability of nerve endings to properly release the chemical that sends the message to the next nerve. This is followed by a period of massive over excitation (cramps, tremors, spasms), which finally tails off to paralysis. Fortunately, bites from Kraits are rare due to their nocturnal nature. Before the development of antivenin, the fatality rate was a whopping 85%. Even if antivenin is administered in time, you are far from assured survival. Death usually occurs within 6-12 hours of a Krait bite. Even if patients make it to a hospital, permanent coma and even brain death from hypoxia may occur, given potentially long transport times to get medical care.

Eastern Brown Snake

Don’t let the innocuous name of this snake fool you, 1/14,000 of an ounce of its venom is enough to kill an adult human. Coming in a variety of species, the Eastern Brown snake is the most venomous. Unfortunately, its preferred habitat is also along the major population centers of Australia. The Brown snake is fast moving, can be aggressive under certain circumstances and has been known to chase aggressors and repeatedly strike at them. Even juveniles can kill a human. The venom contains both neurotoxins and blood coagulants. Fortunately for humans, less than half of bites contain venom and they prefer not to bite if at all possible. They react only to movement, so stand very still if you ever encounter one in the wild. [Image Source]

Fierce Snake or Inland Taipan

While I did say that I would not include multiple sub-species in this list, the incredible Inland Taipan deserves a spot of its own. It has the most toxic venom of any land snake in the world. The maximum yield recorded for one bite is 110mg, enough to kill about 100 humans, or 250,000 mice! With an LD/50 of 0.03mg/kg, it is 10 times as venomous as the Mojave Rattlesnake, and 50 times more than the common Cobra. Fortunately, the Inland Taipan is not particularly aggressive and is rarely encountered by humans in the wild. No fatalities have ever been recorded, though it could potentially kill an adult human within 45 minutes.

Belcher’s Sea Snake

The most venomous snake known in the world, a few milligrams is strong enough to kill 1000 people! Less than 1/4 of bites will contain venom, and they are relatively docile. Fisherman are usually the victims of these bites, as they encounter the species when they pull nets from the ocean. Found throughout waters off South East Asia and Northern Australia.

Does your sense of smell reveals when you're going to die?

2011-01-16T07:44:00.000-08:00

Have you stopped being able to identify familiar smells? Then you may be about to die, according to a new study.

A group of scientists studied a group of over 1,000 older people who weren't sick or suffering dementia. They gave each person a test to see how well they could identify 12 familiar odors. Those with the lowest scores had a much higher probability of dying over the next year than those who couldn't.

According to the journal Chemical Senses, where the researchers published their findings:

Olfactory scores ranged from 0 to 12 correct (mean = 9.0, SD = 2.2). In an initial analysis, risk of death decreased by about 6% for each additional odor correctly identified (hazard ratio = 0.94; 95% confidence interval: 0.90, 0.98). Thus, mortality risk was about 36% higher with a low score (6, 10th percentile) compared with a high score (11, 90th percentile). The association persisted in subsequent analyses that controlled for naming ability, disability, cerebrovascular disease, characteristic patterns of leisure activity, depressive symptoms, and apolipoprotein E genotype. The results indicate that difficulty identifying familiar odors in old age is associated with increased risk of death.

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World's weirdest X-rays

2011-01-13T05:21:00.000-08:00

From broken bones to disease the X-Ray is one of the most useful medical advancements in history. But as these images show they can also reveal some of the most gruesome and bizarre results. Here, an X-ray shows the abdomen of a patient that has swallowed two forks, a ballpoint pen and a toothbrush. The items are located in the intestine

The comical yet disturbing results are taken from hospitals around the world and show how accidents come in all shapes and sizes. This X-ray shows a nail (upper centre) lodged in bones of the index and middle fingers of an adult male, having penetrated through the skin

A historical X-ray of the foot of a Boer War (1899-1902) soldier, showing a gunshot wound. A Mauser bullet has become lodged between the metatarsal bones of the big and second toes. The bullet has not broken any bones; but the end phalanges of the toes are deformed, perhaps from tight army boots and long marches. This radiograph was made by the soldier positioning his foot above a photographic plate, while an open electric discharge tube emitted the X-rays

A coloured X-ray of objects swallowed and lodged in the intestine of a patient, including a spoon and a blade

          A coloured X-ray of an object (safety pin) lodged in the oesophagus of a woman

A coloured X-ray (front view) of the chest of a 60-year-old patient with schizophrenia, showing a foreign body (24mm diameter) inhaled into an airway (bronchus) of the lung

An X-ray of the foot of a patient who stood on a fork

A coloured X-ray of the abdomen of a patient with dementia that has swallowed a razor (centre left) and razor blades (upper right)

A victim's lacerated fingers- due to fight with a knife wielding attacker

Another patient who stood on a fork

A coloured X-ray of a knife (upper right) in the chest cavity

An X-ray of a bullet (conical object at centre left) embedded in the chest of a patient

An X-ray showing a toothbrush that was swallowed as a 'dar

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Onion Cream Treats New Stretch Marks

2011-01-12T09:14:00.000-08:00

A moisturizing cream whose active ingredient is extract of onion can help take the redness out of new stretch marks. New stretch marks were also softer and smoother in 54 women who used the cream for three months, says Zoe Draelos, MD, a consulting professor of dermatology at Duke University Medical Center in Durham, N.C.
"The stretch marks did not go away," she tells WebMD. "But [after several weeks of treatment], the cream made them look and feel better," she says.
The study, funded by Merz Pharmaceuticals, which makes the cream, was presented at the annual meeting of the American Academy of Dermatology. Draelos has served as a consultant to Merz.

Stretch Marks Affect Men, Too

Draelos estimates that up to 98% of women and 75% of men have stretch marks, which appear as wavy, linear red scars, typically on the hips, breasts, thighs, and stomach of women, and the buttocks and pectoralarea of men.
They form when the skin is rapidly stretched, such as during puberty, pregnancy, and rapid weight gain, says Joshua Zeichner, MD, director of cosmetic and clinical research at Mt. Sinai Medical Center in New York City. He was not involved with the research.
"Unfortunately, stretch marks are permanent. Exercise and diet won't help," he says.
They're not harmful to your health, but many people are bothered by their appearance. The marks slowly fade and become flat on their own, but that can take years.
As a result, doctors have been looking for a product to make new stretch marks look and feel better, Draelos says.

Why Onions for Stretch Marks?

Any insult to the skin -- be it a cut or wound or the rapid stretching that drives the formation of stretch marks -- is accompanied by inflammation.
Onions contain flavonoids, a type of antioxidant, that have anti-inflammatory properties, Draelos says.
The new product also contains pennywort, a plant found in Asia, Africa, and the Americas that has anti-inflammatory properties and is widely used in Indian naturopathic medicine for ulcer healing, she says.
And it has sulfur, which fights bacteria and infection, and a moisturizing cream to help rehydrate the skin, Draelos says.

Onion Creams Helps Stretch Marks Look, Feel Better

The new study involved 54 women, aged 18 to 45, with new, matching stretch marks on their outer thighs.
They worked a quarter-sized amount of the cream into one of their stretch marks twice a day for 12 weeks. The other stretch mark received no treatment.
As judged by the women themselves, the treated stretch mark looked better, was less red, and was softer and smoother than the untreated stretch mark. They started to notice the difference after two weeks of treatment, and the difference persisted through all 12 weeks of the study.
The researchers also noted that the treated stretch mark looked and felt better beginning with the second week, compared with the stretch mark that was not treated. But it wasn't until the eighth week of treatment that they noticed a substantial difference in redness.
None of the women reported any side effects.
Although the cream wasn't tested in men, Draelos says she'd recommend it for men, too.
Zeichner says, "Doctors and patients have been looking for good treatment options for stretch marks. The use of a cream containing onion extract may be a promising option for a problem that currently has no cure."

New Shipboard Laser Weapon Takes Aim at Would-Be Pirates

2011-01-12T06:17:00.000-08:00

Pirate Laser Me eyes, matey! BAE Systems via New Scientist

A new long-range laser weapon takes a page from Greek antiquity to thwart marauding pirates at sea. It won’t set their ships on fire, but it can let pirates know they have been spotted and might make them wish for an eye patch, as New Scientist reports.

British defense giant BAE Systems is testing a new green-light laser, which can automatically modulate its intensity depending on the weather and distance to target. Piracy has been on the rise, according to the International Maritime Bureau — there were 430 pirate attacks last year, including an audacious attack on a U.S. warship in the Indian Ocean.

Most pirate ships tend to be small 20-foot skiffs, explains BAE’s Bryan Hore, so the 3-foot-wide beam was designed to target an entire pirate vessel and its crew.

From nearly a mile away, it’s bright enough to simulate accidentally looking at the sun, according to New Scientist. Sunglasses would only make it worse, because they would make the laser appear even brighter against the darkened background. It wouldn’t cause any lasting harm, but the bright light would be distracting and could make it harder for pirates to aim their AK-47s, Hore said.

During the siege of Syracuse 2,200 years ago, the Greek physicist Archimedes purportedly used a network of mirrors to focus sunlight into heat rays and set invading ships on fire. The historical myth has been sufficiently busted (with help from President Obama), and now some historians think the heat ray was used to baffle the marauders instead of setting them ablaze.

BAE has tested its laser from ranges up to three-quarters of a mile. If it obtains enough funding, the laser could be ready for sale in about a year.

Uggs May Give Your Feet Nasty Diseases

2011-01-10T08:50:00.000-08:00

Not only are Uggs probably ruining your feet and, like, totally over, but now some doctors say they breed foot fungus that can seep into your toe nails and is hard to get rid of. Give them a rest, already!

Man Survives Without Using Soap For 18 Months—Could You?

2011-01-09T12:42:00.000-08:00

What would happen if you went a year and a half without washing with soap and shampoo? Would your girlfriend ditch you? Friends loathe having to invite you 'round? Or, like Richard Nikoley and Sean Bonner, would life just...go on?

Nikoley's gone without either for 18 months now, and Bonner, inspired by Nikoley, just a year. Both claim life is much easier now, with Nikoley seeing some pleasant bonuses:

"What I've found over these 18 months is that I never even thought of the money I was saving. Hell, a decent sized bottle of shampoo and body wash would last me months anyway. Oh, and then there's the travel size versions. No, what has made this experience oh so satisfying is that I don't have to worry about any of that anymore — ever. Don't have to buy it. Don't have to carry it. Don't ever run out of it. Don't have to get it tossed in the dumpster by TSA goons."

Bonner, writing on Boing Boing, can't see himself ever going back to buying bottles of chemicals:

"The future? I will definitely be sticking with this. I'm still annoyed it took me 35 years to learn what I clearly already knew as a baby kicking and screaming when my parents tried to wash my hair. At least that's what I want to assume I knew back then. I know now, but I'd still rather not think about how much I spent on soap and shampoo and related products over the years when they were likely causing all the problems I was trying to protect against."

Funnily enough, he recounts a time when a hairdresser washed his hair with shampoo before he knew what was happening—and suffered dandruff and unruly hair for weeks afterward.

Supposedly one in 230 million people around the world are allergic to water, and cannot bathe without their skin being brought out in rashes, so suffer far worse than Nikoley and Bonner would if forced into a shower with a bar of soap. But would you go 18 months without using cleansing products on your skin or hair?

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Scent of a Woman's Tears Lowers Men's Desire

2011-01-09T06:13:00.000-08:00

What a downer! Men who smell a woman's tears experience a dip in both sexual arousal and testosterone, a new study finds.

The libido-dampening effect occurred even when the men never saw the women cry and didn't know they were sniffing tears, researchers report online today (Jan. 6) in the journal Science.

The results are the first to suggest that humans can chemically communicate with tears.

"We conclude that there is a chemosignal in human tears, and at least one of the things the chemosignal does is reduce sexual arousal," study researcher Noam Sobel, a neuroscientist at the Weizmann Institute of Science in Israel.

An odorless signal

It's obvious that humans communicate both verbally and visually, but recent research has shown that chemosignals also carry lots of information. Chemosignals may be entirely odorless – in Sobel's study, participants were unable to tell the difference between tears and saline solution – but they affect both behavior and physiology.

Earlier work by Sobel and others found that male sweat can boost mood and sexual arousal in women, as well as bumping up their levels of the stress hormone cortisol. And a 2004 study published in the journal Hormones and Behavior found that the scent of a lactating woman's nursing pads could increase sexual desire in other women.

Scientists have found that emotional tears contain more protein than do the everyday tears that protect the eyes. Until now, however, chemical signals in tears had been found only in mice and blind mole rats. To investigate the phenomenon in humans, Sobel and his colleagues put out fliers recruiting people who could cry easily. They got about 70 responses (only one of them from a man), he said. The researchers screened the volunteers and found the three best criers – women who could produce at least a milliliter of tears while watching a sad movie.

The researchers then had 24 men sniff both saline and the women's tears. Both the tears and saline had been allowed to roll down the women's cheeks, as a way to control for any odors in their skin or sweat.

None of the men could tell the difference between the two samples, and even the experimenter was kept in the dark about which she was presenting. The men then saw photos of women's faces, which they rated for sadness and sexual attractiveness.

"To our surprise, there was absolutely no influence on sadness or empathy or anything of that sort that we had expected," Sobel said. However, "sexual arousal dropped after sniffing tears."

Questions about crying

The researchers tried the experiment again, this time priming 50 male volunteers for sadness by showing them a depressing video clip. Again, sniffing tears instead of saline didn't make men sadder. But it did lower their sexual arousal and their testosterone levels.

As a final experiment, the researchers repeated the tear-sniffing with 16 men who were situated inside a functional magnetic resonance imaging machine (fMRI). The fMRI shows patterns of blood flow in the brain, which coincide with brain activity.

Sure enough, the tears reduced activity in areas known to be involved in sexual arousal. Those areas included the hypothalamus, an almond-size structure just above the brainstem, and the left fusiform gyrus, which is on the surface of the left side of the brain.

The study was "very well done," said Charles Wysocki, a psychobiologist at the Monell Chemical Sense Center in Philadelphia.

"Tears contain proteins that are also found in the underarm," Wysocki told LiveScience. "And in the underarm they bind the chemicals that we think are involved with chemical communication, so it's quite possible that these proteins found in tears might be doing the same thing."

The finding is likely to remain controversial until researchers discover a specific chemical that causes the response, however. Sobel’s lab is now working to identify the compound in tears that sends the signal.

"There's something that's operating at a very low concentration to cause this effect," George Preti, an organic chemist at the Monell Center who wasn't involved in the study, told LiveScience. "It's obviously a molecule with a lot of oomph."

The study also raises questions of whether children's and men's tears send signals, and what signals are conveyed within one’s own gender by tears. Whether happy tears send a signal is another open question, Wysocki said.

"You can understand where women might not be aroused when they are, in fact, crying," Wysocki said. "And maybe they're telling the male, it's a chemical communication way of saying 'No' or at least 'Not now.' You can see that, it makes sense. But if doesn't make sense to have the same chemical signal being released when a guy gets back after a year of tour of duty and his wife greets him with tears of happiness and pleasure. I would speculate that those tears would be containing something else."

Given the newfound parallel between rodents and human tears, the idea that humans are the only mammals to cry emotional tears may be wrong, Sobel said.

"Human emotional tears were considered unique because they were considered purely an emotional response," he said. "But what we've shown is that they're a form of chemosignaling, at least in part, and that puts them on par with mice tears and mole-rat tears."

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Babies Born Slightly Early Often Don’t Get Proper Care

2011-01-09T03:54:00.000-08:00

Babies born just a few weeks early are often cared for as if they were full-term babies — for instance, they are sometimes allowed to leave the hospital shortly after birth. But such practices may harm the infants' health and put them at risk for visits to the emergency room, according to a new study.
The study adds to the growing body of evidence showing that hospitals need to change the way they treat late-preterm infants, said study researcher Dr. Ramzan Shahid, medical director of the newborn nursery at Loyola University Medical Center in Maywood, Ill.
Babies born between 34 weeks and 36 weeks of pregnancy are considered late-preterm; full-term pregnancies lasts at least 37 weeks.
The new study showed babies born at 36 weeks were almost twice as likely to require a visit to the emergency room within the first month of their lives as infants born even earlier, at 34 or 35 weeks."The ones that are born earlier, those babies are monitored more closely," Shahid said.
"I think pediatricians feel that [the 36-week-old infants] are almost full term, and they feel that they will probably do fine," Shahid said. "I think there's a false sense of security that they have with the 36-week infants."
Late-preterm babies are not fully mature and are at risk for breathing problems and jaundice, Shahid said. They can have trouble feeding, maintaining a proper body temperature and keeping normal blood sugar levels.
However, because these babies can weigh as much as full term infants, their health problems can remain hidden to those who care for them during their first few days of life.
"The thing about these babies is some of them are big," said Dr. Gabriel Escobar, a pediatrician at Kaiser Permanente Medical Center in Oakland, Calif., who has researched the health of late-preterm infants but was not involved in the new study. "So because the baby looks like a term baby, [it gets] treated like a term baby. And that's not good."
In recent years, the number of late-preterm infants born in the United States has risen, the researchers said. Now, about 400,000 babies are born between 34 and 37 weeks of pregnancy, making up 70 percent of all preterm births, Shahid said.
Shahid and his colleagues reviewed charts of late-preterm infants born at Loyola University Hospital between January 2005 and December 2008.
Late-preterm infants that were sent home less than 48 hours after birth were 2.3 times more likely to have repeat hospital visits than late-preterm infants that stayed in the hospital longer.
And late-preterm babies cared for in the newborn nursery were about three times more likely to have repeat hospital visits as those that stayed in the Neonatal Intensive Care Unit (NICU).
"When the babies are in the NICU...they have a higher level of care," Shahid said.
When babies are cared for in the NICU, he explained, doctors probably identify any health issues that could later result in a hospitalization. Babies in the regular newborn nursery might not be monitored as closely, he said. "So then those issues are not identified, and those babies are sent home, and they come back to the hospital a little while later."
There is no current standard for how late-preterm infants should be monitored, or whether they should stay in the nursery or NICU, Shahid said. Previous work has found that these infants are at risk for cognitive problems, such as lower IQs and emotional problems, including anxiousness, at age 6.
Shahid's study was presented at the American Academy of Pediatrics National Conference and Exhibition in San Francisco in October, but was not widely reported. The researchers recently issued a news release on their findings.
Pass it on: While late-preterm babies may appear similar to full-term babies in terms of their size and weight, they may need extra care to prevent repeat hospitalizations.
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How Fast You Walk May Predict How Long You’ll Live

2011-01-08T23:16:00.000-08:00

Doctors who are interested in measuring life expectancy may now have a simple way to do it — researchers have discovered that walking speed can be a useful predictor of how long older adults live.
Those who walked 1 meter per second (about 2.25 mph) or faster consistently lived longer than others of their age and sex who walked more slowly, the study showed.
"We're able to show that a person's capacity to move strongly reflects vitality and health," said study researcher Dr. Stephanie Studenski, a professor of medicine at the University of Pittsburgh.
However, the researchers also emphasized that the purpose of this study wasn't to get people to walk faster in hopes of living longer.
"Your body chooses the walking speed that is best for you, and that is your speed, your health indicator," Studenski said. "And that's what it really is: an indicator. Going out and walking faster does not necessarily mean you will suddenly live longer. You still need to address the underlying health issues."
The researchers showed they could reliably predict the 10-year survival rate of a group of people based on how fast they walked along a 4-meter track.
The walking speed for those with the average life expectancy was about 0.8 meters per second (about 1.8 mph) for most age groups of both sexes. Walking speed was a more accurate predictor of life expectancy than age or sex, the study showed.
The numbers were especially accurate for those older than 75. This suggests that for older people, walking speed could be a sort of "vital sign," like blood pressure and heart rate, the researchers said.
"When you think about it, a sick person would not have that certain spring in their steps. Therefore, it should not be surprising that walking speed can provide a simple glimpse into aging and health status," Studenski said.
The findings were based on analysis of nine previous studies that examined the walking speed, sex, age, body mass index, medical history and survival rate of almost 34,500 people.
The way we walk and how quickly we can walk depends on our energy, movement control and coordination, which, in turn, requires the proper functioning of multiple body systems, including the cardiovascular, nervous and musculoskeletal systems, Studenski told MyHealthNewsDaily. Because of this, researchers have associated walking speed with health in the past.
"But in the past, we simply knew that walking faster was better," said Dr. Matteo Cesari, who wrote an editorial accompanying the new findings, but was not involved in the study.
"This study provides us the numerical basis to estimate survival for each walking speed measured on an older person," Cesari said.
"When we measure, for example, blood pressure, we need a cut-off point to understand whether it is normal or not. Similarly, we now have a cut-off point to understand whether the overall health of a person is normal for his/her age by simply testing their walking speed," Cesari told MyHealthNewsDaily.
Studenski said this finding will have many practical applications. It is a quick and inexpensive way for seniors to gauge their own health. Similarly, doctors can monitor and remedy their patients' quality of life based on this. Walking speed, and in turn, mobility, will be a useful way to measure whether someone is still maintaining a healthy, active and independent lifestyle.
The study will be published tomorrow (Jan. 5) in the Journal of the American Medical Association.
Pass it on: Older adults who walk faster than 1 meter per second may live longer than those who walk more slowly.
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Antibiotic Shows Promise to Treat Irritable Bowel Syndrome

2011-01-08T18:44:00.000-08:00

An antibiotic called rifaximin has shown promise in treating irritable bowel syndrome (IBS) in two large clinical trials by targeting bacteria in the gut, researchers found.
Four weeks after the beginning a two-week-long treatment with the drug, 41 percent of people who took it said they had relief from their IBS symptoms — including bloating, abdominal pain and loose and watery stools. Of those who took the placebo, 32 percent reported relief, the study showed.
With "the other medications studied in the past, you have to stay on them, otherwise one week after stopping, you're back the way you were," said study researcher Dr. Mark Pimentel, director of the Gastrointestinal Motility Program and Laboratory at Cedars-Sinai Medical Center in Los Angeles. But with rifaximin, "you treat it, it's kind of a one-and-done, for at least a period of time."
Rifaximin is currently approved by the Food and Drug Administration (FDA) to treat traveler's diarrhea and hepatic encephalopathy, a condition that results when the liver is unable to remove toxic substances from the blood. The FDA will likely make a decision about approving rifaximin to treat IBS within the next two to three months, Pimentel said.
The new studies will be published tomorrow (Jan. 6) in the New England Journal of Medicine. Salix Pharmaceuticals, Inc., the manufacturer of rifaximin, provided funding for the study. Pimentel is a consultant to Salix, Inc., and serves on its scientific advisory board.
Finding relief
IBS is one of the most common disorders in the United States, according to the National Institute of Diabetes and Digestive and Kidney Diseases. As many as one in five Americans has the condition, which is characterized by severe cramps, bloating, constipation, diarrhea and abdominal pain.
IBS can be caused by excessive amounts of bacteria in the small intestine, Pimentel said. Current medications for IBS may relieve symptoms, but to provide lasting relief from the condition, a drug has to kill the gut bacteria that causes it.
Pimentel and his colleagues tested rifaximin in two trials with more than 600 patients in each.
The people in the trials all had IBS with mild to moderate diarrhea and bloating. Some were assigned to take 550 milligrams of rifaximin three times a week for two weeks, and others were assigned a placebo.
Pimentel said patients experienced relief even eight weeks after they stopped taking the drug, whereas other IBS drugs only provide relief if the patient is currently taking the drug.
Rifaximin versus other drugs
Rifaximin is different from other antibiotics one might take for a urinary tract infection or a sinus infection, Pimentel said. He said it less likely to create antibiotic resistance because 99 percent of it passes out of the body in the feces, rather than being absorbed into other areas of the body outside the gut.
People who took the drug to treat IBS also didn't have any more or less side effects than people who took the placebo, Pimentel said.
Pass it on: The antibiotic rifaximin could soon be approved for use in treating irritable bowel syndrome.
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Scent of a Woman's Tears Lowers Men's Desire

2011-01-08T15:43:00.000-08:00

What a downer! Men who smell a woman's tears experience a dip in both sexual arousal and testosterone, a new study finds.
The libido-dampening effect occurred even when the men never saw the women cry and didn't know they were sniffing tears, researchers report online today (Jan. 6) in the journal Science.
The results are the first to suggest that humans can chemically communicate with tears.
"We conclude that there is a chemosignal in human tears, and at least one of the things the chemosignal does is reduce sexual arousal," study researcher Noam Sobel, a neuroscientist at the Weizmann Institute of Science in Israel, told LiveScience.
An odorless signal
It's obvious that humans communicate both verbally and visually, but recent research has shown that chemosignals also carry lots of information. Chemosignals may be entirely odorless – in Sobel's study, participants were unable to tell the difference between tears and saline solution – but they affect both behavior and physiology.
Earlier work by Sobel and others found that male sweat can boost mood and sexual arousal in women, as well as bumping up their levels of the stress hormone cortisol. And a 2004 study published in the journal Hormones and Behavior found that the scent of a lactating woman's nursing pads could increase sexual desire in other women.
Scientists have found that emotional tears contain more protein than do the everyday tears that protect the eyes. Until now, however, chemical signals in tears had been found only in mice and blind mole rats. To investigate the phenomenon in humans, Sobel and his colleagues put out fliers recruiting people who could cry easily. They got about 70 responses (only one of them from a man), he said. The researchers screened the volunteers and found the three best criers – women who could produce at least a milliliter of tears while watching a sad movie.
The researchers then had 24 men sniff both saline and the women's tears. Both the tears and saline had been allowed to roll down the women's cheeks, as a way to control for any odors in their skin or sweat.
None of the men could tell the difference between the two samples, and even the experimenter was kept in the dark about which she was presenting. The men then saw photos of women's faces, which they rated for sadness and sexual attractiveness. [Read Sexual Pheromones: Myth or Reality?]
"To our surprise, there was absolutely no influence on sadness or empathy or anything of that sort that we had expected," Sobel said. However, "sexual arousal dropped after sniffing tears."
Questions about crying
The researchers tried the experiment again, this time priming 50 male volunteers for sadness by showing them a depressing video clip. Again, sniffing tears instead of saline didn't make men sadder. But it did lower their sexual arousal and their testosterone levels.
As a final experiment, the researchers repeated the tear-sniffing with 16 men who were situated inside a functional magnetic resonance imaging machine (fMRI). The fMRI shows patterns of blood flow in the brain, which coincide with brain activity.
Sure enough, the tears reduced activity in areas known to be involved in sexual arousal. Those areas included the hypothalamus, an almond-size structure just above the brainstem, and the left fusiform gyrus, which is on the surface of the left side of the brain.
The study was "very well done," said Charles Wysocki, a psychobiologist at the Monell Chemical Sense Center in Philadelphia.
"Tears contain proteins that are also found in the underarm," Wysocki told LiveScience. "And in the underarm they bind the chemicals that we think are involved with chemical communication, so it's quite possible that these proteins found in tears might be doing the same thing."
The finding is likely to remain controversial until researchers discover a specific chemical that causes the response, however. Sobel’s lab is now working to identify the compound in tears that sends the signal.
"There's something that's operating at a very low concentration to cause this effect," George Preti, an organic chemist at the Monell Center who wasn't involved in the study, told LiveScience. "It's obviously a molecule with a lot of oomph."
The study also raises questions of whether children's and men's tears send signals, and what signals are? conveyed within one’s own gender by tears. Whether happy tears send a signal is another open question, Wysocki said.
"You can understand where women might not be aroused when they are, in fact, crying," Wysocki said. "And maybe they're telling the male, it's a chemical communication way of saying 'No' or at least 'Not now.' You can see that, it makes sense. But if doesn't make sense to have the same chemical signal being released when a guy gets back after a year of tour of duty and his wife greets him with tears of happiness and pleasure. I would speculate that those tears would be containing something else."
Given the newfound parallel between rodents and human tears, the idea that humans are the only mammals to cry emotional tears may be wrong, Sobel said.
"Human emotional tears were considered unique because they were considered purely an emotional response," he said. "But what we've shown is that they're a form of chemosignaling, at least in part, and that puts them on par with mice tears and mole-rat tears."
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Double Dose: Two Doses of Chickenpox Vaccine Better Than One

2011-01-08T11:10:00.000-08:00

Two doses of the chickenpox vaccine more effectively protect kids from the virus than just one dose, according to a new study.
One dose of the vaccine prevented chickenpox 86 percent of the time, while two doses prevented chickenpox 98.3 percent of the time, in a study of 140 children who received either one or two doses of the vaccine, the researchers said.
This study is the first to show independent clinical evidence that two doses of the vaccine are more effective than one, said study researcher Dr. Eugene Shapiro, professor of pediatrics at Yale University. The Centers for Disease Control and Prevention has recommended two doses of the vaccine for children ages 4 to 6 since 2006.
"Previous studies only looked at antibody responses, but two doses hadn't been shown to prevent the disease more effectively," Shapiro told MyHealthNewsDaily.
Shapiro and his colleagues also examined 71 cases of children with chickenpox in Connecticut. They found that of those children, none of them had received two doses of the vaccine, 66 children (93 percent) received one dose and five children (7 percent) hadn't received the vaccine at all.
The CDC began recommending one dose of the vaccine for children ages 1 to 13 in 1995. In 2006, the agency raised the recommended number of doses to two for kids ages 4 to 6, because of the high frequency of outbreaks in day care centers and schools, he said.
The United States is one of the only countries to recommend two doses of chickenpox vaccine; most recommend one. But the findings should encourage other countries to change their recommendations, Shapiro said.
Although previous studies by the CDC and the vaccine's manufacturer had demonstrated that the two-dose regimen triggers kids' immune systems to produce more antibodies against the virus than one dose, this new study is an independent verification of those results, said Patrick Schlievert, a professor of microbiology at the University of Minnesota who was not involved in the study.
"This is not surprising, but it's really cool that it is so highly effective," Schlievert told MyHealthNewsDaily.
The study will be published in the Feb. 1 issue of the Journal of Infectious Diseases.
Pass it on: Two doses of chickenpox vaccine give more protection than one dose.
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Designer Drugs Turn Deadly, Creating Moral Dilemma

2011-01-08T07:34:00.000-08:00

A synthetic chemist at Purdue University has built a career working with mind-altering substances that interact with receptors in the brain, but some of his work has had unintended consequences that weigh on him. "My research wasn't designed to find drugs that could kill people. I really set out to find drugs that could help us understand the brain and maybe find drugs that could treat psychiatric disorders," the chemist, David Nichols, told LiveScience. [Top 10 Controversial Psychiatric Disorders]?Nichols' studies of mind-altering chemicals did not consider their toxicity in humans, but that did not stop at least one entrepreneur from appropriating the research and creating dangerous drugs that are not yet banned by law.Nichols' story represents a dilemma for scientists, who are left to decide whether to pursue work that could well be misused and cause harm.Nichols first learned his research was being used to create potentially fatal designer drugs – which create effects like those of illegal drugs while skirting the law – more than a decade ago. From lab to streetBeginning in 1982, Nichols' lab began working on MDMA — now known on the street as Ecstasy — because this substance and others like it were believed to hold potential for use in psychotherapy. One of the substances the researchers worked on was called MTA, which had a chemical structure similar to MDMA. Almost 20 years later, Nichols learned from a colleague that MTA had been synthesized outside the lab and sold as tablets called "flatliners." That name was apt, Nichols' observed; by 2002, six deaths had been linked to MTA. "Because I was the only one working on MTA and publishing on it, I was pretty sure they had picked up the molecule from my work," Nichols told LiveScience in an e-mail. In an essay today (Jan. 5) in the journal Nature, Nichols writes that knowing that his work — showing that the effects of MTA in rats could be linked to human deaths — left him "with a hollow and depressed feeling for some time."But he assumed that only a few amateur chemists were behind the designer drugs inspired by his work. This past October, he found out that at least one sophisticated, money-making enterprise was following his work.In an interview for an Oct. 30 story in the Wall Street Journal, an entrepreneurial European chemist named Nichols' research as an inspiration in his quest for new, psychoactive substances to market. The newspaper identified the entrepreneur as David Llewellyn, a Scotsman who was a self-described former crack addict.? His construction business had gone under, and, looking for income, he turned to the "legal high" business, which is much larger in Europe than in the United States. When the article was published, Llewellyn employed eight people in two labs to whip up the pills and sold his products online. [Read the WSJ article]The science behind itNichols describes his research as having two parts. The first focuses on stimulants that activate dopamine receptors (proteins on brain cells to which the substance dopamine can attach), and could potentially provide treatments for Parkinson's disease and for memory and cognitive decline associated with schizophrenia. The second and more notorious half focuses on psychedelic drugs. These compounds can cause dramatic shifts in consciousness, and, when he started on this line of research in 1969, Nichols was interested in finding out why.He now studies how molecules of different psychedelics interact with a particular type of receptor in the brain, which responds to the neurotransmitter serotonin — a substance that regulates many functions, including mood, appetite and sensory perception. Authorities in Europe continually scramble to identify and ban designer drugs, meaning that entrepreneurs like Llewellyn must come up with new products, according to the Journal. Llewellyn told the newspaper he and his chief chemist search the scientific literature for new ideas, and that they have found Nichols' work especially valuable. But little work is done to test the toxicity of these substances, according to Nichols. His lab may give a promising substance to rats; however, it doesn't test the effects of prolonged exposure or high doses on rats, or conduct any sort of human testing. His rat and human studies have shown MTA causes a surge of serotonin release from brain neurons, but without the high associated with Ecstasy. Instead, because MTA also blocks the enzyme that breaks down serotonin, it can lead to "serotonin syndrome," which involves high body temperatures and seizures that can lead to death. In one case, Nichols said, he and fellow researchers decided not to study a molecule that would likely have a potent Ecstasy-like effect, because of its potential to destroy serotonin neurons in the brain. The damage the work could have incurred was greater than the possible gain in knowledge, he said.? ?Moral dilemmaGenerally, society has avoided putting any intentional restrictions on research to prevent the results from being used by those with nefarious intent, according to Ruth Faden, director of the Johns Hopkins Berman Institute of Bioethics, who is not involved in Nichols' research. This is because, in almost all cases, it is impossible to determine whether a piece of scientific knowledge will lead to more evil than good, Faden said. Beyond that, exercising that judgment could lead to censorship or abuse, she added. [7 Absolutely Evil Medical Experiments]"Basically, we live with a certain amount of acceptance that any piece of knowledge has some potential to be used toward, if you like, the dark side," Faden said. While scientists do not generally have the responsibility to anticipate harmful, or just plain evil, uses for their work, when presented with information that it may have immediate, negative consequences, as Nichols was, scientists must use their own judgment as to whether to continue that line of study, Faden said. The dilemma is agonizing from the standpoint of the individual scientist, but "probably, that is where our best protection lies," she said.
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How to Look Younger? Have Older Friends

2011-01-08T03:59:00.000-08:00

Scientists have confirmed a rather simple tip for looking younger that doesn't require plastic surgery, Botox or expensive anti-wrinkle creams: Hang out with old people.
We underestimate the age of a person in his or her 30s if we have previously looked at pictures of older people, researchers found.
They also found it worked in reverse: We overestimate ages after looking at pictures of younger people.
"People are actually quite good at guessing the age of the person next to them," said study researcher Holger Wiese, of Jena University in Germany. But in their experiment, "we are able to change the subjective perception of a face."
The researchers asked 24 young adults to look at pictures of 15 female and 15 male faces. Each image was doctored to show what the person would look like in his or her 20s, 30s, 40s, 50s, 60s and 70s.
The volunteer were systematically wrong at estimating other people's ages after they had looked intensely at faces of people of a specific age group.
For example, if many faces of elderly people were shown on the computer first, followed by the face of a middle-age person, the volunteers made out the middle-age person to be substantially younger than he or she was. But after first studying younger faces, the volunteers estimated the middle-age person as being substantially older.
The effect was strongest if the series of older faces and subsequent image of a younger face were the same gender, the study showed.
The results held regardless the viewers’ age and gender, the researchers said. They ?said they did not yet know how long the effect lasts.
"The age of the person next to you is one of the most important characteristics for our perception of other people. This leads to exciting crossovers into other areas of scientists who are dealing with the interactions of social groups," Wiese said.
The study was published in the Nov. 23 issue of the journal Vision Research.
Pass it on: We underestimate a person's age if we've just seen older people.
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Vaccine Could Help Humans Kick Cocaine Habit

2011-01-07T23:49:00.000-08:00

A vaccine that takes the high out of cocaine for mice could also be useful in treating human addiction, researchers announced Tuesday (Jan. 4).
The vaccine combines a segment of the common cold virus with a molecule similar to cocaine. After receiving the shot, mice dosed with the drug didn't respond with the hyperactive symptoms of a cocaine high, the researchers reported online in the journal Molecular Therapy. The vaccine works by turning the body's immune system against cocaine, preventing the drug from reaching the brain.
"Our very dramatic data shows that we can protect mice against the effects of cocaine, and we think this approach could be very promising in fighting addiction in humans," study researcher Ronald Crystal, a professor of genetic medicine at Weill Cornell Medical College, said in a statement.
The researchers built the vaccine by taking apart an adenovirus, a type of virus responsible for the some cases of the common cold. They discarded the components that cause disease and kept those that alert the immune system to the virus' presence. Next, they hooked the adenovirus parts onto a molecule similar to cocaine. The real thing wasn't used because the cocaine lookalike was more stable and elicited better immunity, Crystal said.
When injected into regular lab mice, the vaccine triggered a strong immune response: anti-cocaine antibodies, or small immune proteins that target invaders. Cocaine usually doesn't elicit an immune response, but the addition of the cold virus parts "trained" the immune system to go after the drug: When isolated in the lab, the antibodies neutralized cocaine, the researchers found.
Next, the researchers dosed the vaccinated mice with cocaine. Despite the drug exposure, the animals didn't get high — an effect that lasted at least 13 weeks.
"While other attempts at producing immunity against cocaine have been tried, this is the first that will likely not require multiple, expensive infusions, and that can move quickly into human trials," Crystal said. "There is currently no FDA (Food and Drug Administration) approved vaccine for any drug addiction."
The drug will have to go through extensive testing in humans to make sure it is safe and effective before it could receive approval from the FDA. However, Crystal said, he suspects the vaccine will work best on cocaine addicts who are trying to quit.
"The vaccine may help them kick the habit, because if they use cocaine, an immune response will destroy the drug before it reaches the brain's pleasure center," Crystal said.
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College Students Value Self-Esteem Over Sex

2011-01-07T19:45:00.000-08:00

Sex, favorite foods, alcohol, a visit with a best friend and a paycheck – a self-esteem boost trumps them all for most college students, according to two new studies that asked students to rate the pleasant activities they most desired. "These are college students, look at this list of activities," said Brad Bushman, lead study researcher and a professor of communication and psychology at The Ohio State University. "College students love sex, they love to eat — any place there is free food, they are there," Bushman told LiveScience, continuing through the list. "And yet they love self-esteem more."When the results of the two studies were broken down by gender, however, self-esteem didn't trump everything. Male students preferred it to all other activities, but among women, self-esteem boosts, such as those linked with getting a good grade or a compliment, rated neck-and-neck with money and friends. In the first study, Bushman's team asked 130 University of Michigan students, who received course credit, to think about their favorite food, sexual activity and self-esteem building experiences. Then they had to rate on a scale from 1 to 5 how much they liked it – "How pleasant would it be to eat it (food), do it (sex), or have that experience (self-esteem)?" – and how much they wanted it – "How much do you want to eat it (food), do it (sex), or have that experience (self-esteem)?"In the second study, the 152 students rated how much they wanted and liked the same pleasurable experiences described in the first study as well as receiving a paycheck, seeing a best friend and drinking alcohol. Overall, the participants liked all the activities more than they wanted, or needed, them, which is healthy, the researchers said. But the difference between liking and wanting was the smallest for self-esteem building experiences. This is significant, because addiction research suggests that addicts tend to "want" the object of their addiction more than they actually "like" it, according to Bushman. "Notice for self-esteem the gap is the smallest, so if people are addicted to anything, they are addicted to self-esteem," he said, cautioning that the study results don't indicate any kind of addiction. As part of the first study, participants took a test they were told measured intelligence. Afterward, they were told that if they waited an additional 10 minutes, they could have the test rescored and possibly improve their score. The researchers found that the greater the gap in favor of wanting a self-esteem boost versus liking it, the more likely a student was to wait. These results represent a problematic obsession with self-esteem, according to the researchers. Americans have come to think of boosting self-esteem as a solution to many societal problems, such as teen pregnancy and drug abuse, according to Bushman. "But I think that is backwards," he said. "Good performance has to come before, not after, self-esteem."There are also behavioral implications. "The problem isn't with having high self-esteem; it's how much people are driven to boost their self-esteem," said study researcher Jennifer Crocker, a psychology professor at The Ohio State University. "When people highly value self-esteem, they may avoid doing things such as acknowledging a wrong they did. Admitting you were wrong may be uncomfortable for self-esteem at the moment, but ultimately, it could lead to better learning, relationships, growth and even future self-esteem."Both studies are published online in the Journal of Personality and will appear in a forthcoming print issue. Follow Science-live on Twitter @Sciencelive1.

Young Women Get HPV Shots After Talking It Over With Mom

2011-01-07T15:20:00.001-08:00

Mothers may play a key role in whether their daughters get the human papillomavirus (HPV) vaccine, even if the daughters have already left the nest.
A new study found college-age women who talked with their mothers about the HPV vaccine were nine times more likely to get it than those who did not discuss it.
"It is an encouraging finding, because it shows that communication between mothers and daughters can be very helpful, even if it may be difficult sometimes," said study researcher Janice Krieger, an assistant professor of communication at Ohio State University.
However, researchers noted that the study was small and focused on students at one particular university, so its findings might not be representative of the population as a whole.
Many mothers and daughters may be uncomfortable talking about the HPV vaccine because it is designed to prevent the spread of a sexually transmitted virus, Krieger said.
But getting the three-shot vaccination series is important because a persistent HPV infection may cause cervical cancer, the researchers said. The Centers for Disease Control and Prevention recommends that girls and women ages 11 to 26 receive the vaccine. HPV is the most common sexually transmitted infection, and will infect about half of sexually active people in the United States during their lifetimes.
Two vaccines are currently approved by the Food and Drug Administration to protect girls and women against HPV: Gardasil, manufactured by Merck & Co., and Cervarix, manufactured by GlaxoSmithKline. The study involved 182 mother-daughter pairs. All of the daughters were Ohio State students, and their average age was 20.
The daughters mailed a questionnaire about the HPV vaccine to their mothers and completed a similar questionnaire themselves.
Overall, 137 of the mother-daughter pairs said they had talked about the HPV vaccine; the other 45 pairs reporting not discussing the vaccine.
Results showed that daughters who discussed getting the vaccine with their mothers, and those who reported believing that the vaccine was safe and effective in preventing HPV-related diseases, were more likely than the others to get the vaccine .
The researchers also found that fears about susceptibility to HPV and about the severity of HPV-caused illness — on the parts of mothers or daughters — were not related to whether they talked about the issue.
"Fear does not seem to be the motivator," Krieger said.
The data don’t show what the women talked about when they discussed the HPV vaccine, but Krieger said she suspects that one topic was the vaccine's cost, which has been reported to range from $360 to $600 for the series of three shots.
That could be one reason few young women are vaccinated. It also would be one reason why it is important to get mothers involved, even after their daughters reach adulthood, Krieger said.
"Most women in early adulthood don’t have a lot of extra money, and even if they do, a preventive vaccine like the HPV vaccine may not be high on their list of things to buy," She said.
One recent study found that just one-third of teens and young women who start the three-dose vaccine series actually finish, and almost three-quarters don't start it at all.
"Mothers may be afraid to bring up the topic, but it doesn’t have to be a conversation focused on sex. Mothers can talk about how the HPV vaccine is safe and effective, and that it prevents cancer," Krieger said.
The study appears in the January issue of the journal Human Communication Research.
Pass it on: Moms may play an important role in persuading their college-age daughters to get the HPV vaccine.
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