Wednesday, January 31, 2007

Brain bleeds in 1 of 4 vaginal birth babies

BEIJING, Jan. 31 (Xinhuanet) -- A recent study has confirmed that one in four babies who experience vaginal birth suffer a limited amount of intracranial bleeding, but the bleeding is limited and has no apparent effect.

The study by John Gilmore, M.D., of the University of North Carolina School of Medicine, and colleagues used magnetic resonance imaging. MRI did not show signs of bleeding for babies born by caesarian delivery, they reported in the February issue of Radiology.

"Small bleeds in and around the brain are very common in infants who are born vaginally," Dr. Gilmore said. "It seems that a normal vaginal birth can cause these small bleeds."

Gilmore said although more research is needed on the implications of the hemorrhages, vaginal birth has not suddenly become unduly risky.

"Obviously, the vast majority of us who were born vaginally and may have had these types of bleeds are doing just fine," he said. "Humans have been born vaginally for a very long time, and our brains probably evolved to handle vaginal birth without major difficulty."

Gilmore and colleagues said intracranial hemorrhage in full-term infants is usually associated with symptoms such as apnea, bradycardia and seizures. A variety of factors has been suggested to account for the bleeding, including prolonged labor and assisted delivery.

But for this study, the researchers studied 88 asymptomatic newborns, evenly divided between male and female, of whom 65 were delivered vaginally and the remainder by caesarian.

The babies were studied using a 3-Tesla MR machine, without anesthetic, between the ages of one and five weeks, the researchers said.

Seventeen of the babies -- or 26 percent -- had bleeding, including 16 subdural, two subarachnoid, one intraventricular, and six parenchymal hemorrhages. Seven infants had two or more types of bleeding. None of the infants with bleeding had been delivered by C-section.

Intracranial bleeding was significantly associated with vaginal birth, but not with prolonged duration of labor or with traumatic or assisted vaginal birth.

Typically, such small hemorrhages resolve over time without causing problems, the researchers said, although larger events may cause such issues as seizures, learning disabilities, or problems with motor development.

The author noted several limitations of the study which may have led to underestimates of the frequency of bleeding.

"The images were not obtained immediately after birth but in weeks one to five after birth, and, perhaps, we missed cases of intracerebral hemorrhage that had resolved. Also, our imaging protocol did not include T2-weighted or magnetic susceptibility-weighted images, which might be even more sensitive for depiction of hemorrhage."

They also pointed out that "no follow-up images were obtained to determine imaging resolution of hemorrhage, and no clinical follow-up was performed after the identification of intracerebral hemorrhage."

"We just don't know at this time what these bleeds may mean over the long term," Gilmore said. "Ultimately, we hope to be able to determine whether intracerebral hemorrhage is associated with later neurodevelopmental problems."

The group plans to follow this cohort longitudinally to see whether the perinatal bleeding is associated with future difficulties, such as idiopathic epilepsy.

The research was support by grants from the National Institute of Mental Health and the University of North Carolina School of Medicine. The researchers said they had no financial conflicts.

Tuesday, September 26, 2006

European space probe unmasks 'face' on Mars

European space probe unmasks 'face' on Mars

European space probe unmasks 'face' on Mars

Associated Press

BERLIN — For decades, photos of what appeared to be a huge, face-shaped rock formation on Mars — or even a statue of Elvis — fueled theories of intelligent life on the Red Planet.

But high-resolution stereo cameras from the European Space Agency's Mars Express orbiter have debunked that myth with the clearest pictures yet of the region where the so-called face was found, ESA has said.

According to Michael McKay, an ESA engineer on the team that sent Mars Express into orbit, the new photos are so much sharper that they reveal that the area on a 1976 photograph by NASA's Viking 1 orbiter is one of many such raised surfaces in the greater Cydonia region.

In 1998 and 2001, new, sharper pictures of the region were taken by NASA's Mars Global Surveyor and revealed simply a rugged landform. But that didn't halt public speculation.

"People automatically thought, 'My goodness, it's a face. There must be intelligent life on Mars. Maybe the Martians built this huge monument to indicate that there is intelligent life and we should come and visit,'" McKay said. "Other people squinting their eyes looked at it and thought Elvis, The King, is alive and on Mars."

The so-called Martian mesas are still interesting for planetary geologists. McKay said the photos can help analyze the geological processes that were at work to create the Cydonia region.

Tuesday, August 22, 2006

Friendly bacteria gum for teeth

Scientists have developed a chewing gum containing friendly bacteria which they say can help prevent tooth decay.

The good bugs in the gum prevent other harmful mouth bacteria from sticking to and attacking the teeth.

Toothpastes and mouthwashes containing Lactobacillus anti-caries are also in the pipeline, German chemical company BASF told Chemistry and Industry.

Friendly bacteria, normally found in live yoghurt, are already purported to be good for treating bowel conditions.


Another potential use of Lactobacillus include the prevention of body odour. BASF are looking to produce a deodorant which can stop the odour-producing bacteria in the armpit.

The bacterium responsible for dental cavities, Streptococcus mutans, persistently colonises the surface of the teeth, where it converts sugar into aggressive acids that breaks down the enamel.

L. anti-caries reduces the concentration of this harmful bacterium in the mouth making S. mutans clump together, preventing them from adhering to the teeth.

The BASF scientists say the gum has been tested on large numbers of people and has the ability to significantly reduce bacterial levels.

Dr Andreas Reindl of BASF said: "The effectiveness has been demonstrated and the first oral hygiene products containing probiotic lactobacilli are scheduled to appear in 2007."

'Keep brushing'

Dentists advise that the best way to keep your teeth in good condition is to ensure that you clean them regularly to get rid of any plaque build up.

It is also important to have a regular check up at the dentist - most suggest once every six months to a year.

Dr Gordon Watkins, a member of the British Dental Association's health and science committee, cautioned: "These new products will not remove the need to brush your teeth as their action is targeted against just one bacterium.

"It's not a substitute for brushing the teeth, because this removes the plaque that contains a whole range of bacteria that causes gum disease and bad breath.

"The best way to minimise tooth decay is to reduce consumption of sugars; strengthen the teeth through the use of fluoride; and brush teeth to remove dental plaque."

The World Health Organization estimates that 5 billion people world-wide suffer from tooth decay.

Thursday, August 10, 2006

New Drug For Alzheimer's

WASHINGTON - Scientists have discovered molecular janitors that clear away a sticky gunk blamed for
Alzheimer's disease — until they get old and quit sweeping up.
The finding helps explain why Alzheimer's is a disease of aging. More importantly, it suggests a new weapon: drugs that give nature's cleanup crews a boost.
"It's a whole new way of thinking in the Alzheimer's field," said Dr. Andrew Dillin, a biologist at California's Salk Institute for Biological Studies who led the new research.
The discovery, published Thursday by the journal Science, was made in a tiny roundworm called C. elegans.
What do worms have to do with people? They're commonly used in age-related genetics research, and the new work involves a collection of genes that people harbor, too. Dillin's team from Salk and the neighboring Scripps Research Institute already is on the trail of potential drug candidates.
About 4.5 million Americans have Alzheimer's, a toll expected to more than triple by 2050 as the population grays. The creeping brain disease gradually robs sufferers of their memories and ability to care for themselves, eventually killing them. There is no known cure; today's drugs only temporarily alleviate symptoms.
Nor does anyone know what causes Alzheimer's. The lead suspect is a gooey protein called beta-amyloid. All brains contain it, although healthy cells somehow get rid of excess amounts. But beta-amyloid builds up in Alzheimer's patients, both inside their brain cells and forming clumps that coat the cells — plaque that is the disease's hallmark.
Thursday's study reveals one way that cells fend off amyloid buildup, and that natural aging gradually erodes that detoxification process.
"Every pathway we can discover that modifies amyloid provides us with new drug targets," said Dr. Sam Gandy, a neuroscientist at Philadelphia's Thomas Jefferson University and an Alzheimer's Association spokesman. "This now opens up a new pathway" for developing anti-Alzheimer's drugs.
Worms can't get Alzheimer's. So Dillin's team used roundworms that produce human beta-amyloid in the muscles of the body wall. As the worms age, amyloid builds up until it eventually paralyzes them; they can wiggle only their heads.
Then the researchers altered genes in a pathway called insulin/IGF-1, long known to be key in controlling lifespan. Making the worms live longer protected them from paralysis.
So in slowing down normal aging, something also slowed the buildup of toxic amyloid. But what?
Enter those cellular janitors, two proteins in that gene pathway.
One, named HSF-1, breaks apart amyloid and disposes of it, the researchers discovered. Natural aging slows HSF-1, so it can't keep up with the necessary detoxification.
Another protein called DAF-16 jumps in to help buy a little more time, by clumping extra amyloid together in a way that makes it less toxic.
That was a key finding, Dillin said: Until recently, scientists thought amyloid clumps, or plaques, were the bigger problem. His research supports more recent findings that smaller amyloid tendrils inside cells are the really poisonous form.
"We think probably the HSF-1 is the preferred way" to dispose of amyloid, Dillin said. "By the time you see the plaques, it's too late."
Mammals, including people, have these same proteins. Dillin now is repeating his experiment in mice to be sure they work the same way.
Scientists already are creating drugs to try to rid the brain of amyloid. These cleanup proteins point to a novel way to do that. The hope: Create drugs that boost their effects, and amyloid might not build up in the first place. Dillin said some initial drug attempts are showing promise in his worms.
The proteins won't be the brain's only natural amyloid scrubbers, noted Gandy, whose own research points toward involvement of another age-related gene.
The study is key for an additional reason, he added.
"We all knew that aging increases the risk for Alzheimer's," but not why, Gandy explained. "Now there's a direct link. ... It gives the molecular connection between aging and Alzheimer's."
And this process of "toxic aging" likely plays a role in still other neurodegenerative diseases, Dillin said, citing similar research with Huntington's disease.

Sunday, July 16, 2006

Test to predict lung cancer

A BLOOD test that looks for the body's immune response to tumours may provide an easy way to find lung cancer in patients long before an X-ray or CT scan.

The blood test correctly predicts the most common type of lung cancer years before the patients were diagnosed with the disease, US researchers have reported.

If the test is proven, it may become the first new cancer blood screen since the prostate-specific antigen test. The lung cancer test is owned by 20/20 GeneSystems.

"These data suggest antibody profiling could be a powerful tool for early detection," wrote the researchers in the Journal of Thoracic Oncology.

Non-small-cell lung cancer is the most common type and has an average five-year survival rate of only 40 per cent.

Lung cancer is the world's biggest cancer killer, with 10 million people diagnosed every year and half of all diagnosed patients dying within one year.