"Well," he began, "to go back to the very beginning of my interest in stem cells the focus of our research has been directed toward challenging the notorious Hayflick limit. Back in the 1960s, Professor Leonard Hayflick discovered that when tissue cells are taken from the body and cultured in a laboratory dish, those cells grow and divide about fifty times, give or take, and then they stop. They have reached old age, senescence. The physical basis of the Hayflick limit is a section of DNA known as telomere, which gets shorter each time the cell divides. Eventually the telomeres become so short that all cell division stops. It's like an internal clock telling them the game is over. They've had their innings." "And you're saying you've found a way to beat the clock, to stop the telomeres from getting shorter?" "All cells possess a gene known as the telomerase gene, which can restore the telomeres to their youthful length. But in most cells the gene is permanently repressed and inactive. It is only found in egg and sperm cells, and in cancer cells." He gazed away for a moment as though collecting his thoughts. Then he turned back. "However, we've found that by isolating and inserting an active copy of the telomerase enzyme into adult stem cells, which can be found in minute quantities throughout the body, we can set their clock back to zero. We extract cells, 'immortalize' them with telomerase, and then return them to the body as a youthful infusion." "And is that what you'd be doing for Mom?" "There'd be a series of injections, but given what appears to be her level of mental awareness right now, the procedure probably can be accelerated." He patted Nina on the shoulder. "All right," Ally said "but can you use the same procedure for someone's heart?" "Well, yes and no," he said. "Did you bring your medical records? I should have a look at them before making any pronouncements." To prepare for this moment, she'd printed off a copy of the medical files she'd scanned into her computer. "There're a lot of files," she said, opening her bag. "I've got copies of my EKGs over the past eleven years. Dr. Ekelman, my cardiologist, says my condition is getting progressively worse." She took the folder out of her bag and handed it to him. He flipped through the files with what seemed an absent manner, almost as though he already knew what was in them and was just going through the motions. Then he looked up.