Word: cellularized
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...What we were seeing," says Hayflick, now a professor at the University of California, San Francisco, "was the concept of cellular aging: growing old in the microcosm of a Petri dish...
...actuarial hourglass that gave it only so much time to live and no more. If the clock could be found--and, more important, reset--both the cells and the larger corpus that gave rise to them might be made immortal. Of course, hypothesizing the existence of such a cellular timekeeper was one thing; finding it and manipulating it were something else again. In the years since, senescence scientists have taken two approaches to achieving this goal...
...first idea researchers have explored is broadly thought of as the cellular-damage model of aging. For any complex system--whether it's made of inorganic metal or protoplasmic goo--the mere act of doing the work it was designed to do carries a price. No sooner does the hardware begin operating than its parts begin wearing out and its journey to the junkyard begins. Cells are not spared this fate, and one of the functions that takes the most out of them is the job of processing food...
...antioxidants, such as beta-carotene, actually seem to be associated with an increase. In either event, few contemporary aging researchers think self-medicating at a salad bar is the best way to extend the human life-span. Far more promising might be new research into another by-product of cellular metabolism: glycosylation--or what cooks call browning...
Although he made history when he discovered the limits on cell replication in the lab, Hayflick left a question unanswered: why the cells die. In the years following his work, biologists mapping human chromosomes looked for a gene that enforced cellular mortality, but found nothing. One thing that did catch their eyes, however, was a small area at the tip of chromosomes that had no discernible purpose. Dubbed a telomere, the sequence of nucleic acids did not appear to code for any traits. Instead it resembled nothing so much as the plastic cuff at the end of a shoelace that...