Thanks for the laugh Greg. After the day I've had I needed that . You always
come through. Shirley
-----------------------------------------------------
Click here for Free Video!!
http://www.gohip.com/freevideo/

-----Original Message-----
From: Greg Sterling <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Thursday, February 24, 2000 11:16 AM
Subject: Re: NEWS: BBC: Bird brains offer stem cells hope


>Janet,
>Interesting news.  What will they discover next?  I am to the point that
I'm
>willing to try anything even if it causes me to break out in song in the
>spring.
>
>This would also confirm many people's opinion of me as a proverbial "bird
>brain".
>:)
>Greg
>47/35/35
>
>----- Original Message -----
>From: "janet marie paterson" <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Thursday, February 24, 2000 9:46 AM
>Subject: NEWS: BBC: Bird brains offer stem cells hope
>
>
>> Bird brains offer stem cells hope
>>
>> Thursday, 24 February, 2000, 13:00 GMT - A new development concerning
stem
>cells is keeping them at the forefront of biomedical research. Stem cells,
>it is believed, have the ability to develop into any other type of cell.
>>
>> Some scientists say that controlling them will herald a revolution in
>medicine and a new way to treat disease because it would open the way to
>cell replacement.
>>
>> In an intriguing example of this ongoing research scientists have used
>bird brains. They have coaxed new brain cells to grow from elusive adult
>stem cells. There are important implications for repairing human brains
>damaged by Parkinson's and Alzheimer's disease.
>>
>> By destroying certain brain cells in zebra finches the scientists say
they
>have prompted the growth of new brain cells. Describing their research in
>the journal Neuron, they say they believe that neural stem cells must be
the
>source of the new neurons.
>>
>> "This is, we believe, the first example where it has been demonstrated
>that one can induce the birth of new brain cells and that they actually
>contribute to a complex behaviour," said Jeffrey Macklis, a neuroscientist
>at Harvard University.
>>
>> "It is a step toward attempting the same in mammals" he added.
>>
>> The researchers chose zebra finches because of an interesting variation
in
>bird biology.
>>
>> Canaries stop singing every autumn when a population of brain cells
>responsible for song-generation die. Over the winter, a whole new
population
>of neurons grows back and in the spring the canaries learn their songs all
>over again.
>>
>> But zebra finches lack this seasonal cycle. Instead, their brains
generate
>a continuous trickle of new neurons.
>>
>> Until recently scientists believed that brain cells did not regenerate
but
>they now know that new cells do grow to a limited degree, especially in
>brain regions called the olfactory bulb and the hippocampus. One theory
>receiving serious attention holds that when certain neurons die, they
signal
>stem cells to produce replacements.
>>
>> Macklis's team selectively killed one kind of song-related neuron in
their
>zebra finches. The birds, as predicted, partly lost their ability to sing.
>But three months later they were singing as normal.
>>
>> When the researchers looked at their brains, they saw that the neurons
had
>grown back, in much the same way that canary neurons come back. They say
>they are now performing more experiments to see just where the new cells
>came from but they suspect they coaxed stem cells into action.
>>
>> Stem cells are cells that can develop into other types of cells and as
>such they have the potential to be used to replace cells that have been
lost
>of damaged.
>>
>> The new-found ability to grow stem cells from human embryos in the
>laboratory was hailed by Science magazine as one of the major breakthroughs
>of recent years.
>>
>> Scientists are trying to find ways to use either adult or embryonic stem
>cells, or both, to regenerate various forms of tissue, including brain
cells
>of patients with disease such as Alzheimer's or Parkinson's.
>>
>> They are however difficult to isolate and grow. Controversially they can
>be taken from aborted foetuses or from embryos left over from IVF
>(test-tube) fertilisation programmes. In many countries this is illegal.
>>
>> Some researchers say that there may be a solution to the ethical problems
>of obtaining stem cells from embryos. Many tissues in the human body
contain
>stem cells. Usually they develop into more cells of the tissues they are in
>but there is hope that they can be re-programmed.
>>
>> There is some recent evidence that they can be enticed to go back to an
>unspecialised 'blank' state. This line of research has the promise to
obtain
>stem cells without using human embryos.
>>
>>
>> By BBC News Online science editor Dr David Whitehouse
>> BBC News Online: Sci/Tech
>> http://news.bbc.co.uk/low/english/sci/tech/newsid_655000/655194.stm
>>
>> janet paterson
>> 52 now / 41 dx / 37 onset
>> a new voice: http://www.geocities.com/janet313/
>> 613 256 8340 PO Box 171 Almonte Ontario Canada K0A 1A0
>>