Study peeks at how normal brains grow
Fri, 18 May 2007 04:35:35 GMTBy LAURAN NEERGAARD, AP Medical Writer
WASHINGTON - Can you get smarter than a fifth-grader? Of course, but new research suggests some of the brain's basic building blocks for learning are nearing adult levels by age 11 or 12.
It is the first finding from a study of how children's brains grow. The most interesting results are yet to come.
About 500 super-healthy newborns to teenagers, recruited from super-healthy families, are having periodic MRI scans of their brains as they grow up. They also get a battery of age-appropriate tests of such abilities as IQ, language skills and memory.
The project, funded by the National Institutes of Health, is tricky work.
Move during an MRI, and the image blurs. Because scientists cannot sedate healthy children, they are having to get crafty to keep their subjects still. Tired toddlers are put in the scanners at naptime; mom squeezes in for a cuddle and earplugs help block the machines' noisy banging. Six-year-olds wear earphones and watch favorite videos beamed into the scanner.
The MRI images measure how different parts of the brain grow and reorganize throughout childhood.
Overlap them with the children's shifting behavioral and intellectual abilities at each age, and scientists expect to produce a long-sought map of normal brain development in children representative of the diverse U.S. population.
On Friday, scientists were publishing a sneak peek at some surprising early results.
Performance on a variety of cognitive tasks — working memory, vocabulary, spatial recognition, reasoning, calculation — rapidly improves between age 6 and 10, but then levels off.
"We don't honestly know why," said Dr. Deborah Waber of Children's Hospital Boston, who led the analysis published in the Journal of the International Neuropsychological Society.
This is a snapshot of 6- to 18-year-olds' abilities during their first study visit. Results may change after researchers observe each child's progress with age and compare their MRI scans, she said.
The adolescent brain is still growing. Indeed, the region responsible for things such as impulse control and moral judgment is the last to mature, sometime in the early 20s, said Dr. Jordan Grafman of the NIH's National Institute of Neurological Disorders and Stroke.
The study did not evaluate those kinds of skills. "It's an incomplete picture," he said.
But the age finding does make sense, suggesting a foundation necessary for higher learning is in place by puberty, said Dr. John Gilmore of the University of North Carolina School of Medicine. The brain-development specialist was not involved with the project.
Scientists already knew that before age 12, the brain is racing to wire itself, making more connections between nerve cells that in turn enlarge vital regions. This is a time of rapid learning, the reason it is easier to learn a foreign language as a young child than as a teenager or adult, Gilmore said.
After puberty, the process slows and the brain "prunes" itself, focusing less on installing new wiring than on programming and refining what is already there.
"Obviously, learning continues to happen," Gilmore said. But the new study says that "by 10 or 12, kids have the basic building blocks they need to learn."
The study also found that girls start with a slightly better verbal ability but boys catch up by adolescence; they have an equal aptitude for math. While children from low-income families scored slightly lower on IQ tests, earlier suggestions of a bigger gap are due to poorer health among poor families.
Once those key MRI scans are added to the children's ability tests, scientists will have a better idea of the range of normal childhood development. Then they can use the data to help figure out what goes wrong in brain diseases such as autism.
USDA OKs chickens fed tainted pet food
Fri, 18 May 2007 15:49:31 GMTWASHINGTON - About 80,000 chickens that were fed contaminated pet food scraps can be released for processing because testing showed meat from the birds is safe to eat, the Agriculture Department said Friday.
The chickens, bred to lay eggs hatched for chicks, had been held on Indiana farms after eating feed that included an industrial chemical blamed in the deaths of cats and dogs.
Their feed was supplemented with pet food scraps containing melamine and related compounds. Testing showed that melamine does not accumulate in birds and is eliminated by their bodies quickly, the USDA said.
Previously, the department cleared thousands of pigs given feed also made using pet food scraps.
Melamine contamination has been blamed for the deaths of an unknown number of dogs and cats, resulting in the recall of more than 100 brands of pet food.
While the dog and cat food was lethal to some pets, the diluted use of pet food scraps in animal feed apparently did not sicken any farm animals. Nor in turn do any of those animals pose a health risk to humans if eaten, according to the USDA and Food and Drug Administration.
FDA advisers back new smallpox vaccine
Fri, 18 May 2007 00:37:49 GMTWASHINGTON - Government advisers backed a second-generation smallpox vaccine on Thursday as safe enough to be used if the virtually extinct virus ever reappears.
The vaccine maker, Acambis Plc, already has provided 192.5 million doses of the experimental vaccine to a U.S. stockpile. But future production may depend in part on whether the http://www.acambis.com/
Food and Drug Administration: http://www.fda.gov/
More Japanese seek stress compensation
Fri, 18 May 2007 00:38:47 GMTBy ERIC TALMADGE, Associated Press Writer
TOKYO - More Japanese workers than ever claimed and received compensation for mental-health problems caused by workplace stress last year and a similar trend was seen for families of employees who died from work-related suicides, officials said Thursday.
A government study found the number of employment-related suicides hit a record 65 in 2006, compared to 42 the previous year, Health Ministry official Junichiro Kurashige said.
The number of workers who received compensation for work-induced mental illness was 205, also a record and up 61 percent from a year earlier, he said. The number of applications for compensation for mental illness or suicide also rose sharply, to 819 cases, a 24 percent jump.
The numbers reflect a push by the government to get more workers or their families to seek compensation if they are legitimately entitled to it, and Kurashige said the recorded cases probably reflect only a tiny fraction of the overall problem.
Japan's suicide rate is among the highest in the industrialized world. More than 32,000 Japanese killed themselves in 2004, the bulk of them older Japanese suffering financial woes as the country struggled through a decade of economic stagnation.
In response, the Japanese government has earmarked substantial funds for programs to help those with depression and other mental illnesses and is more actively involved in encouraging those affected to come forward.
The figures are also seen as reflecting a change in social attitudes toward mental illness.
Though once seen as shameful, more Japanese are willing to acknowledge they suffer from depression or stress-related illnesses now than in the past, and the government has begun easing its compensation restrictions to allow more people to qualify.
"Before, people tried to hide that they were suffering from depression," said Mikio Mizuno, a lawyer specializing in death from overwork. "Now, it has become more widely known that people suffer and commit suicide from work-related depression, leading to more applications for workers' compensation. The psychological burden from work is also increasing."
Financial worries have been a problem since the world's second-largest economy stagnated in the early 1990s after a burst of high growth, leading to bankruptcies, layoffs and an increased focus on jobs with fewer benefits and long-term security.
The economic has been growing again, but more slowly, and Japanese workers often face long overtime hours with little or no compensation and must make long commutes to work.
Get real and save Indian youth from AIDS official
Thu, 17 May 2007 17:41:28 GMTBy Kamil Zaheer
NEW DELHI - Banning sex education on the grounds that it offends Indian sensibilities puts young lives at risk and jeopardizes the fight against AIDS, a senior health official said.
Six states in India, which has the most people living with HIV/AIDS in the world, have banned sex education for adolescents or refused to implement the curriculum, saying the course material was too explicit or that it was against Indian culture.
Some politicians accuse educators of encouraging permissiveness among young people.
&;We are not giving ideas to young people,&; National AIDS Control Organization chief Sujatha Rao said. &;They are already there.&;
&;Some people are in denial that young people experiment with sex. They need to get real,&; she told Reuters late on Wednesday.
Rao's comments came before the cabinet approved on Thursday a plan that envisages spending 116 billion rupees ($2.8 billion) over the next five years in its most ambitious anti-AIDS project yet.
The plan for 2007-12 will focus on prevention and increasing the number of people on first-line AIDS drugs. The government plans to provide 80 billion rupees and the rest will come from foreign donors like the World Bank.
India has the world's highest caseload for HIV/AIDS with 5.7 million HIV-positive people, according to the United Nations. But sex is not spoken about openly in most parts of the country.
An India Today magazine survey last year showed one in four Indian women aged between 18 and 30 in 11 cities had sex before marriage.
Yet over 40 percent of all Indian women have not heard of AIDS, creating a dangerous combination of lack of knowledge and greater sexual activity.
&;There will be a huge negative impact if you don't provide sex education, given the vulnerability of young people to the virus,&; Rao said earlier, addressing MPs who are also doctors.
&;Are you more concerned about culture than the lives of young people?&; she said.
The states of Gujarat, Maharashtra, Madhya Pradesh, Chhattisgarh and Karnataka have banned or refused to implement sex education curriculum introduced last year.
The Hindu nationalist government in Madhya Pradesh said sex education had &;no place in Indian culture&; and plans to introduce yoga in schools instead.
India has 165,000 reported AIDS cases of which around 50,000 are in the age group of 15-29 years.
&;We are worried about our young people,&; Rao said.
Minorities prefer depression counseling to drugs
Fri, 18 May 2007 19:35:00 GMTNEW YORK - When it comes to depression therapy, minorities are more likely than whites to prefer counseling to medication, according to a large U.S. survey.
In an Internet survey of about 75,000 Americans, researchers found that African Americans, Hispanics and Asian Americans were two to three times more likely than whites to say they'd rather be treated with talk therapy than with drugs for depression.
Minorities were also less likely to believe that depression stems from biological changes in the brain and were more likely to think antidepressants are addictive, according to findings published in the journal General Hospital Psychiatry.
&;This study documents that, overall, ethnic minorities hold attitudes toward depression and depression treatment that are distinct from those of white participants,&; lead study author Dr. Jane Givens, of Boston University Medical Center, said in a statement.
The preference many minority patients may have for counseling illustrates the importance of making such therapy available and covered by insurance, Givens and her colleagues point out.
Their findings come from a Web-based survey of adults who completed a standard questionnaire to gauge depression symptoms. After the respondents received feedback on the likelihood that they were depressed, they were asked about their attitudes toward depression therapy.
The researchers found that among the subjects with a high risk of depression, white respondents were more likely to prefer medication -- 42 percent would opt for antidepressants, while 34 percent would choose counseling.
In contrast, only 26 percent of African Americans preferred medication, while 54 percent would opt for counseling. For Asian Americans, 25 percent wanted drug therapy and 49 percent preferred counseling. Among Hispanic respondents, the corresponding figures were 32 percent and 46 percent.
Native Americans were the only minority group that showed preferences similar to white respondents.
In each group, some respondents said they would want neither form of therapy.
In general, African Americans, Hispanics and Asian Americans were also more likely than whites to believe antidepressants can be addictive and less likely to believe that drugs were an effective way to treat depression.
Other studies, according to Givens's team, have found that while rates of depression are similar across racial lines, African Americans and Hispanic Americans are less likely to receive treatment. A better understanding of minorities' beliefs and preferences for treatment might help close that gap, they note.
SOURCE: General Hospital Psychiatry, May/June 2007.
Simple tests may predict progression to Alzheimer39s
Thu, 17 May 2007 18:20:16 GMTBy Will Boggs, MD
NEW YORK - Simple cognitive tests can help predict the likelihood that a person with mild cognitive impairment will progress to Alzheimer's disease , researchers report in the journal Neurology.
Among 539 older individuals with mild cognitive impairment, the overall rate of progression to AD was 16 percent per year during a 36-month study, Dr. Adam S. Fleisher from the University of California, San Diego, and associates report in the journal.
They found that scores on several tests of mainly memory and recall, combined with the person's APOE4 status, was 81 percent accurate in predicting progression from mild cognitive trouble to AD. APOE4 gene variant is well known to be associated with an increased risk of developing Alzheimer's disease.
A second paper in Neurology identifies symptoms associated with progression to AD.
Dr. Katie Palmer and colleagues at the Karolinska Institute in Stockholm, Sweden, investigated whether mood- and motivation-related depressive symptoms and anxiety in 185 individuals with mild cognitive impairment were related to the future development of AD.
Although depressive symptoms were not associated with an increased risk of progressing from mild cognitive impairment to full blown AD, the authors report, each increasing number of anxiety symptoms nearly doubled the risk of progressing to AD.
The risk of progression to AD was also increased significantly in those reporting problems with decision making and in those with persistent worrying, the researchers note.
Among elderly persons without cognitive impairment, the report indicates, the risk of AD nearly doubled with each increasing number of mood-related depressive symptoms.
Elderly patients presenting with both anxiety and memory problems should be closely followed and monitored, &;as there is a very high risk that they will develop Alzheimer's disease within three years,&; Palmer told Reuters Health.
SOURCE: Neurology, May 8, 2007.
Moderate drinking may lower kidney cancer risk
Fri, 18 May 2007 19:32:06 GMTBy Karla Gale
NEW YORK - Having a drink or two per day appears to modestly decrease the risk of developing kidney cell cancer, new research findings suggest, regardless of the type of alcoholic drink that is consumed.
Multiple studies have hinted at an inverse association between alcohol and kidney cancer, investigators point out in the Journal of the National Cancer Institute. &;But previous studies were inconclusive, and it is not clear whether alcohol itself affects risk, or if the effects are due to specific types of beverages,&; lead author Dr. Jung Eun Lee told Reuters Health.
Eun Lee, from Brigham and Women's Hospital in Boston, and her colleagues therefore analyzed data from 12 clinical studies. &;The data were derived from general populations in the United States, Canada, Sweden, Finland and the Netherlands,&; the investigator said, making their study &;one of the largest to examine alcohol intake and risk of kidney cancer.&;
The total number of subjects included 530,469 women and 229,575 men. At study entry, the subjects had completed food-frequency questionnaires that included alcoholic beverages. The authors defined moderate drinking as the equivalent of &;slightly more than one alcoholic drink per day.&; They excluded subjects who drank more than two drinks per day.
During 7 to 20 years of follow-up, 711 women and 719 men were diagnosed with kidney cell cancer.
This translated into 23 cases for every 100,000 non-drinkers per year and 15 cases for every 100,000 moderate drinkers per year.
After the researchers factored in the effect of age, the risk of kidney cell cancer was 25 percent lower among the moderate drinkers than among the nondrinkers, a statistically significant difference.
There also appeared to be a dose-response relationship - as the amount of daily alcohol consumption increased from about two drinks per week to about one drink per day, the risk of kidney cancer when from 6 percent lower to 25 percent lower, respectively.
The associations were still similar after taking into account risk factors for kidney cancer, including weight, history of high blood pressure, smoking and other factors, the investigators report.
Reproductive history, the use of dietary substances, and total calorie intake, had little impact.
The results were similar for beer, wine, and liquor.
However, the investigators were not able to distinguish between subjects who were moderate daily alcoholic drinkers versus those who tended to drink large amounts sporadically. Therefore the effects of very heavy alcohol use, frequency of use, and various drinking patterns, were unclear, Dr. Eun Lee said.
The investigators suggest that alcohol may reduce the risk of kidney cell cancer by improving insulin sensitivity. Other possibilities include the activity of antioxidant phenolic compounds contained in alcohol, which may help decrease kidney cell cancer risk by removing carcinogenic agents, reducing cancer cell proliferation or promoting cell death.
On the other hand, they add, &;Alcohol per se is most likely the responsible factor.&;
Regardless of the mechanism involved in this moderate reduction in risk, patients should be reminded that alcohol can also increase the risk of many other types of cancer, including breast, liver and esophageal cancer, Eun Lee cautioned.
&;Maintaining a healthy weight and avoiding smoking are the principal known means to reduce the risk of cancer that should be encouraged, and doing so may also reduce the risk of many other cancers, as well as cardiovascular disease,&; the research team concludes.
SOURCE: Journal of the National Cancer Institute, May 16, 2007.
