Tuesday, April 6, 2010

Parkinson's patient's cycling ability stuns doctors

Monday, Apr. 05 2010
Dr. Bastiaan R. Bloem of the Radboud University Nijmegen Medical Center in the
Netherlands thought he had seen it all in his years of caring for patients with
Parkinson's disease. But the 58-year-old man who came to see him recently was a
total surprise.

The man had had Parkinson's disease for 10 years, and it had progressed until
he was severely affected. Parkinson's, a neurological disorder in which some of
the brain cells that control movement die, had made him unable to walk. He
trembled and could walk only a few steps before falling. He froze in place, his
feet feeling as if they were bolted to the floor.

But the man told Bloem something amazing: He said he was a regular exerciser —
a cyclist, in fact — something that should not be possible for patients at his
stage of the disease, Bloem thought.

"He said, 'Just yesterday I rode my bicycle for 10 kilometers' — six miles,"
Bloem said. "He said he rides his bicycle for miles and miles every day.

"I said, 'This cannot be,'" Bloem, a professor of neurology and medical
director of the hospital's Parkinson's Center, recalled in a telephone
interview. "This man has end-stage Parkinson's disease. He is unable to walk."

But the man was eager to demonstrate, so Bloem took him outside where a nurse's
bike was parked.

"We helped him mount the bike, gave him a little push, and he was gone," Bloem
said. He rode, even making a U-turn, and was in perfect control, all his
Parkinson's symptoms gone.

Yet the moment the man got off the bike, his symptoms returned. He froze
immediately, unable to take a step.

Bloem made a video and photos of the man trying to walk and then riding his
bike. The photos appear in the April 1 issue of The New England Journal of

After seeing that man, Bloem asked 20 other severely affected patients about
riding a bike. It turned out that all could do it, though it is not clear why.

Bloem and other Parkinson's specialists were amazed. People with Parkinson's
disease can often dance, run, walk smoothly and do complex movements for a few
minutes if they are given appropriate signals — emotional or visual cues. There
are famous examples, such as a group of Parkinson's patients who were caught in
a fire and managed to run down steps and escape, only to freeze in place when
they got outside.

But this effect, known as the kinesia paradox, does not last long. Riding for
miles and miles is very different from walking for a few minutes. And until
now, Bloem said, it was not known that patients with Parkinson's could ride

He said bicycling offers patients an opportunity to be symptom-free while they
are riding, to look and feel normal, and to get some real cardiovascular

Bloem said he hoped that perhaps regular exercise might slow the progress of
Parkinson's disease. It does in rats, he said.

Friday, April 2, 2010

A finch's decoded genome might help us with speech

By Kim McGuire

When we hear a song for the first time, it often seems like it goes in one ear and out the other, sometimes only few catchy words from a chorus leaving much of an impression.
bullet Hear the sounds of the zebra finch

But when the Australian zebra finch hears its father sing for the first time, those simple melodies activate large, complex gene networks in the bird’s brain, according to new research by an international team of scientists that includes researchers from Washington University and the University of Illinois at Urbana-Champaign.

The findings, published today in the journal Nature, reveal how the team successfully decoded the genome of the zebra finch, only the second bird to have its genetic code completely mapped.

The project provides new insights that will help scientists understand how humans learn language and may someday provide insights into diseases like autism that can inhibit speech, team members say.

"Now we can look deep into the genome, not just at the genes involved in vocal learning, but that the complex ways in which they are regulated," said Richard K. Wilson, the research’s senior author and director of Washington University’s Genome Center. "This information provides clues to how vocal learning occurs at the most basic molecular level in birds and people."

Past research has shown that hundreds of genes light up in the finch’s brain as the bird learns a new song.

The new research show that significantly more genes — about 800 total — are activated by the act of singing.

The team selected the zebra finch for study because songbirds are among few animals that learn how to sing — just like humans. As young birds, the finch "babbles" but eventually learns how to imitate its father.

In contrast, a chicken, the other bird to have its genome sequenced, instinctively knows how cluck. It is not a form of communication learned from other birds.

"There is a functional development parallel between the way a bird learns to sing and a human learns to speak," said David Clayton, a neuroscience professor at the University of Illinois and leader of the group that proposed the genome sequencing project. "The avian brain is quite different in a superficial detail from the mammalian brain or the human brain, but some striking parallels have emerged."

Wes Warren, lead author and genetics professor at Washington University, explained that the zebra finch proved to be the model study organism because they learn to sing in a predictable way over a relatively short span of time and many of their genes are conserved in humans.

Now, scientists can conduct future studies to identify a core set of genes in the finch’s brain and see if any of these are disrupted in people with speech disorders caused stuttering, or stroke and by diseases like autism and Parkinson’s, Warren said.

"It’s just amazing to know that when the finch hears a song, there’s always a gene that corresponds in the brain," he said. "Clearly, that’s going to be even more complex in humans."

Warren said as more animals have their genes sequenced, scientists will be able to draw more comparisons that might yield insight into human development.

Next up for some of the Washington University scientists who participated in the finch project is the sequencing of the parrot genome, which is slated for completion sometime later this year.