ScienceCache
Vol. 218
Feb. 6, 2006
MEMORY PROBLEMS AT MENOPAUSE: NOTHING TO FORGET ABOUT
Women who feel that they become more forgetful as menopause approaches
shouldn’t just “fuhgetabout it”: There may be something
to their own widespread reports that they’re more likely to forget
things as menopause approaches, say scientists who reported results
from a small study last week at the annual meeting of the International
Neuropsychological Society in Boston. The team found that the issue
is not really impaired memory. Instead, the team found a link between
complaints of forgetfulness and the way middle-aged, stressed women
learn or “encode” new information. “This is not what
most people think of traditionally when they think of memory loss,” says
co-author Mark Mapstone, assistant professor of neurology. “It
feels like a memory problem, but the cause is different. It feels like
you can’t remember, but that’s because you never really
learned the information in the first place.” The findings come
from Mapstone and Miriam Weber, memory experts at the University’s
Memory Disorders Clinic who are seeing more and more middle-aged women
who say they are having problems with forgetfulness. “We see
a lot of women who are afraid they are losing their minds,” says
Weber, a senior instructor of neurology, who presented the results
this morning. “A lot of women complain that their thinking or
their memory isn’t what it used to be. Their big fear is that
it’s early Alzheimer’s disease.” The team found nothing
to support the idea that such women are on their way to developing
dementia, but they did find that the women who complained more about
problems with forgetfulness had a harder time learning or “encoding” new
information, which can masquerade as a problem with memory.
Full story
ON THE UP AND UP: ‘DEBLOBBING’ AND THE BIRTH OF MOUNTAINS
Mountain ranges rise to their height in as little as 2 million years – several
times faster than geologists have always thought – according to
two new studies by Carmala Garzione, assistant professor of earth and
environmental sciences. The findings come from two pioneering methods
of measuring ancient mountain elevations, and the results are in tight
agreement. The research papers, which appeared in Science and Earth and
Planetary Science Letters in the last week, mean scientists will have
to re-evaluate tectonic processes that build high elevation plateaus,
such as those in Tibet and the central Andes, where Garzione has done
extensive research. “These results really change the paradigm of
understanding of how mountain belts grow,” says Garzione. “We've
always assumed that the folding and faulting in the upper crust produced
high elevation mountains. Now we have data on ancient mountain elevation
that shows something else is responsible for the mountains’ uplift.” Her
studies showed that the Andes shot up between 10 million and 7 million
years ago, leading to the idea that “deblobbing” created
the mountains. “Deblobbing” is a fancy word scientists use
to describe a process where a dense chunk of the Earth’s mantle
beneath the planet’s crust becomes unstable and begins to flow
downward, acting as an anchor to budding mountains but then breaking
off, sending the mountains sky high in a geologically “short” span
of just a few million years.
Full story
JUNK NO MORE: AN IMPORTANT NEW ROLE FOR ‘WASTED’ DNA
Researchers worldwide are seeking to define ancient, largely undefined
sections of our genetic code, a sort of historic wasteland of DNA, that
may soon be as important to medicine as genes. The research is focusing
on how small regulatory DNA sequences – snippets of DNA containing
crucial instructions – tell genes where, when and to what degree
to turn on. As part of this effort, researchers led by Joseph M. Miano
of the Cardiovascular Research Institute scanned through the vast human
DNA code to reveal for the first time 60 genes influenced by one such
sequence, according to an article published last week in the journal
Genome Research. “Most people don’t realize that genes make
up a very small percentage of the human DNA code,” says Miano. “Genes
are relatively straightforward compared to what lies ahead. We believe
that the real genetic gymnastics, the real intelligence of our system,
is controlled by tiny bits of genetic material that tell genes what to
do.” Growing knowledge of how regulatory sequences control gene
behavior has the potential to create new classes of treatment for nerve
disorders and heart failure. Such sequences may also help to explain
why humans are so complex, despite having one-fifth as much genetic material
as wheat for instance. Scientists already know that genes, specific batches
of code that direct protein construction, comprise just about 2 percent
of all human DNA. And so Miano and others ask the question: What does
the remaining 98 percent of human genetic material do? The presence of
regulatory sequences, which enable a single gene to produce the same
protein at different times, places and concentrations, is likely part
of the answer.
Full story
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