Then, Jeffrey Gray and his team injected brain stem cells from mouse embryos into the brains of the rats. These stem cells then migrated to the damaged areas, and turned into hippocampus brain cells. The rats recovered their memories. These stem cells are truly remarkable - not only do they migrate to where they're needed, but they also turn into the sort of cell that is needed at that particular site. In studies with other brain-damaged animals, the stem cells migrated as far as 8 mm, to get to the damaged area.
Stroke affects mostly the elderly in our society, and enormously increases our health bill.
The scientists in this field think that trials using stem cells to repair damage to the brain will begin by around 2003, and regular medical treatment will begin within five to ten years after that. Now of course, if you're desperately in need of a body part, and somebody grows a compatible one in a test tube, you'd be happy to have the transplant operation. But there is a better way - without surgery. Gradually, the diseased cells would dissolve away, and be replaced by healthy cells that would make insulin - and you would no longer be a diabetic. You often hear of supposed medical breakthroughs, that eventually come to nothing.