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Greg, Considering birds are able to walk, swim and fly ( which we aren't able to do) and to be served up for Thanksgiving dinner, it seems to me that they must have a fair amount of neurological activity. Whereas, some peoples' capabilities leave a lot of room for questioning.. If given a choice, who wouldn't want to be the bird able to fly, sing and be most appreciated during a celebration ? *Seattle* Audrey friend of aussie pwp John 48/40/38?? :) ----- Original Message ----- From: Greg Sterling <[log in to unmask]> To: <[log in to unmask]> Sent: Thursday, February 24, 2000 11:15 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 > > >