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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 >>