Women's Migraines Not Linked to Mental Decline: Study

Researchers have some reassuring news for women who suffer from migraines: There is no strong link between the intensely painful headaches and cognitive decline or dementia.

The research out of Brigham and Women's Hospital in Boston is based on data from 6,349 women ages 45 and older who participated in a health survey. The participants were classified into four groups: no history of migraine, past history of migraine, and continued history of migraine with and without aura. (Auras can cause a person to see flashes of light or feel pins-and-needles sensations before a migraine kicks in.)

After this baseline information was collection, the participants were tested for cognitive function in two-year intervals up to three times. The results, which were published online Aug. 8 in the British Medical Journal, showed no strong relationship between migraines and long-term consequences on cognition, according to the researchers.

"Compared with women with no history of migraine, those who experienced migraine with or without aura did not have significantly different rates of cognitive decline," Pamela Rist, who led the study, explained in a statement from Brigham and Women's Hospital.

"Previous studies on migraines and cognitive decline were small and unable to identify a link between the two," Rist added. "Our study was large enough to draw the conclusion that migraines, while painful, are not strongly linked to cognitive decline."

About 30 million Americans suffer from migraines, but women are three times more likely than men to be impacted by them. The debilitating headaches have been linked to an increased risk of depression and even stroke. Much is still unknown about the chronic condition, but researchers recently found the first genetic link to migraines — a gene variant also found to change the activity of other genes, including one previously linked to disorders such as epilepsy.

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Radiation hotspot in Tokyo linked to mystery bottles

By Yoko Kubota

TOKYO | Thu Oct 13, 2011 1:59pm EDT

TOKYO (Reuters) - A radiation hotspot has been detected in Tokyo seven months into Japan's nuclear crisis, but local officials said on Thursday high readings appeared to be coming from mystery bottles stored under a house, not the tsunami-crippled Fukushima atomic plant.

The Fukushima Daiichi nuclear power plant, struck by a devastating quake and tsunami in March, has released radiation into the atmosphere that has been carried by winds, rain and snow across eastern Japan.

Officials in Setagaya, a major residential area in Tokyo about 235 km (150 miles) southwest of the plant, said this week it found a radioactive hotspot on a sidewalk near schools, prompting concerns in the country's most populated area far from the damaged nuclear plant.

The radiation measured as much as 3.35 microsieverts per hour on Thursday, higher than some areas in the evacuation zone near the Fukushima plant, the center of the world's worst nuclear disaster since Chernobyl 25 years ago.

But the local government found several bottles under the floor of a nearby house emitting high levels of radiation.

"A measuring device, when pointed at them, showed very high readings. Radiation levels were even exceeding the upper limit for the device," Setagaya Mayor Nobuto Hosaka told a news conference.

Officials from the Education Ministry are now looking into the matter, including the contents of the bottles.

Public broadcaster NHK said no one had been living in the house in question.

The city of Funabashi, near Tokyo, said that a citizens' group had measured a radiation level of 5.8 microsieverts per hour at a park, but that the city's own survey showed the highest reading at the park was a quarter of that level.

Radiation levels in the 20 km radius evacuation zone around the Fukushima Daiichi plant ranged from 0.5 to 64.8 microsieverts per hour, government data showed this week.

About 80,000 residents have evacuated this zone. A microsievert quantifies the amount of radiation absorbed by human tissue.

In Yokohama, also near Tokyo, radioactive strontium-90, which can cause bone cancer and leukemia, was detected in soil taken from an apartment rooftop, media reported.

Strontium has been detected within an 80 km zone around the Fukushima Daiichi plant, but this is the first time it has been found in an area so far away, local media added.

Radiation exposure from natural sources in a year is about 2,400 microsieverts on average, the U.N. atomic watchdog says.

Japan's education ministry has set a standard allowing up to 1 microsievert per hour of radiation in schools while aiming to bring it down to about 0.11 microsievert per hour.

(Additional reporting by Kiyoshi Takenaka; Editing by Yoko Nishikawa and Nick Macfie)

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Protein linked with rare disease plays role in aging

By Julie Steenhuysen

CHICAGO | Mon Jun 13, 2011 7:40pm EDT

CHICAGO (Reuters) - The same mechanism that causes children with a rare genetic disease called progeria to age at seven times the normal rate may play a role in normal aging as well, government researchers said on Monday.

The study led by Dr. Francis Collins, director of the National Institutes of Health, suggests aging may not simply be a gradual wearing out of cells.

Instead, it may be an active biological mechanism -- one that might be tinkered with to address age-related diseases.

"I think a lot of people in the past have assumed that the aging of cells and of individuals was just a matter of everything running down," Collins told Reuters in a telephone interview.

"What we are learning at the cellular level ... is that is not right," said Collins, whose study appears in the Journal of Clinical Investigation.

Scientists for several years have been working to understand the key biological processes that trigger aging in hopes of discovering new drugs that could delay or prevent age-related diseases such as cancer, heart disease and Alzheimer's disease.

Much of that has been focused on studying protective caps on the tips of chromosomes called telomeres, which Collins likens to "the aglets on shoelaces that keep the laces from them from getting ratty."

When telomeres become too short and frayed through cell division, the cell eventually dies. But it has not been entirely clear how this comes about.

Based on the study by Collins and colleagues at the National Human Genome Research Institute, it now appears that the same toxic protein that drives the premature aging disorder progeria plays a key role in normal cell aging, Collins said.

Formally known as known as Hutchinson-Gilford Progeria Syndrome, progeria is an extremely rare disease in which children experience symptoms normally linked with old age -- hair loss, wrinkled skin, clogged arteries and arthritis.

Children with the disease often die by the age of 13.

INSIGHT INTO AGING

In a 2003 study, Collins and colleagues found the disease is caused by mutations in a gene called LMNA that makes the toxic protein progerin.

"What this paper does is show the process that is happening in those children is clearly an important process in normal aging," Collins said.

"That same toxic protein that we call progerin, which is made in large quantities in those kids, is also made in your cells and mine" as the cells start to die.

"And it shows the telomeres and progerin are connected," Collins said. "They have been on parallel scientific pathways and we have now found they are actually linked together."

He said when telomeres become too short and frayed, this triggers the production of progerin, signaling to the body that the cell is at the end of its useful life.

Collins says the study shows that instead of being a passive wearing out of cells, aging is an active biological mechanism that is programed into cells.

And understanding this mechanism could lead to new kinds of treatments. Already, a study is underway in children with progeria to see if researchers could block the excess production of progerin.

Collins says more work is needed to understand the biological mechanism of aging.

"We clearly don't have the whole picture," he said.

But understanding the aging process could lead to new ways to slow normal aging, and it underscores the need to continue funding research on rare diseases.

"It is often the insights that come from the rare diseases that teach us something about more common ones," he said.

(Editing by Eric Beech)

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Greenland cold snap linked to Viking disappearance

An iceberg floats in the sea ice near the town of Uummannaq in western Greenland March 18, 2010.

Credit: Reuters/Svebor Kranjc

OSLO | Mon May 30, 2011 4:37pm EDT

OSLO (Reuters) - A cold snap in Greenland in the 12th century may help explain why Viking settlers vanished from the island, scientists said on Monday.

The report, reconstructing temperatures by examining lake sediment cores in west Greenland dating back 5,600 years, also indicated that earlier, pre-historic settlers also had to contend with vicious swings in climate on icy Greenland.

"Climate played (a) big role in Vikings' disappearance from Greenland," Brown University in the United States said in a statement of a finding that average temperatures plunged 4 degrees Celsius (7F) in 80 years from about 1100.

Such a shift is roughly the equivalent of the current average temperatures in Edinburgh, Scotland, tumbling to match those in Reykjavik, Iceland. It would be a huge setback to crop and livestock production.

"There is a definite cooling trend in the region right before the Norse disappear," said William D'Andrea of Brown University, the lead author of the study in the U.S. journal Proceedings of the National Academy of Sciences.

Researchers have scant written or archaeological records to figure out why Viking settlers abandoned colonies on the western side of the island in the mid-1300s and the eastern side in the early 1400s.

Conflicts with indigenous Inuit, a search for better hunting grounds, economic stresses and natural swings in climate, perhaps caused by shifts in the sun's output or volcanic eruptions, could all be factors.

LITTLE ICE AGE

Scientists have previously suspected that a cooling toward a "Little Ice Age" from the 1400s gradually shortened growing seasons and added to sea ice that hampered sailing links with Iceland or the Nordic nations.

The study, by scientists in the United States and Britain, added the previously unknown 12th century temperature plunge as a possible trigger for the colonies' demise. Vikings arrived in Greenland in the 980s, during a warm period like the present.

"You have an interval when the summers are long and balmy and you build up the size of your farm, and then suddenly year after year, you go into this cooling trend, and the summers are getting shorter and colder and you can't make as much hay," D'Andrea said.

The study also traced even earlier swings in the climate to the rise and fall of pre-historic peoples on Greenland starting with the Saqqaq culture, which thrived from about 4,500 years ago to 2,800 years ago.

Scientists fear that the 21st century warming is caused by climate change, stoked by a build-up of greenhouse gases from human activities. An acceleration of warming could cause a meltdown of the Greenland ice sheet, raising world sea levels.

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