Saturday, March 01, 2003

Send in the Clones
Jeff Wheelwright, our ostensible guide to the new world of human cloning ["Being Brave for This New World," Year in Science, January], minimizes the ethical and moral considerations that human cloning raises. The values Wheelwright champions—"economic and medical demands"—are chilling, suggesting that the worth of human cloning will lie in the commodification of life fostered by commerce and the laboratory. And biotech's role as the primary engine of development is hardly encouraging. Human cloning will become a reality because we just can't seem to help ourselves. And I submit that it is precisely that lack of self-restraint that makes us such risky tinkerers with life. Rather than "yield to the human clones" when ambiguities and disagreements face us, as Wheelwright advises, let us summon all the humility and caution within us, remembering that the very deepest value of life is intrinsic. We simply aren't the gods we too often take ourselves to be.

David Seppa
Portland, Oregon

Concealed Cause
Regarding "Headaches to Worry About" [Vital Signs, January]: Paul Austin made a brilliant diagnosis in this case [pseudotumor cerebri] and is to be commended. One thing strikes me as worthy of further inquiry: He describes Crystal as "a 22-year-old wearing heavy makeup." Was she wearing the heavy makeup because she had severe acne? If so, was she taking Accutane, prescribed either by her family physician or her dermatologist? One of the many side effects of Accutane is pseudotumor cerebri.

Ian D. Murphy, M.D.
Toledo, Ohio

Collision Course
Karen Wright's article "Winging It" [Works in Progress, December] brought to my mind the possibility of an interesting correlation between the number of bird deaths caused by wireless-communication towers and the hypothesis that migratory birds rely on geomagnetic cues to assist in navigation. The U.S. Fish and Wildlife Service estimates that at least 5 million birds and as many as 50 million birds are killed annually in collisions with communications towers in the United States. I believe that further investigation should be devoted to the relationship between migratory-bird deaths and the wireless-communication tower signals interfering with a bird's ability to detect the magnetic field. Much research has been devoted to the potential impact that tower lighting has on orientation and navigation but not enough on the effects of the signal itself.

Ken Born
Environmental Resource Policy Department
Monterey, California

Speech! Speech!
In "The Art of, um, Speaking Clearly" [R&D;, November], it seems to me that psychologists Herbert Clark and Jean Fox Tree are approaching the art of speaking from two different directions. They posit that conversation sprinkled with ums and uhs, as a speaker searches for a thought or a word, adds sparkle to the dialogue. The article concludes with: "But woe betide the politician who allows such terms to intrude. 'When I say uh and um in conversation, I'm saying "I'm not ready to go on." If you're a public speaker, you don't want to be telling your audience that,' Clark says. A case in point: Not a single uh or um appears in the recorded inaugural speeches of American presidents between 1940 and 1996." There wouldn't be, or shouldn't be, any ums or uhs in a presidential inaugural or any public speaker's speech for two reasons: First, presidential inaugurals and most, if not all, political speeches are scripted; and second, experienced public speakers prepare to deliver their speech or their pitch, whereas conversation is entirely spontaneous. I believe we're talking, um, apples and oranges here.

Bill Schmeer
Thomasville, Pennsylvania

A New Wrinkle
In his response to a reader's question in Ask the Wizard [R&D;, October], Richard Sontheimer of the University of Iowa College of Medicine incorrectly attributed wrinkling of the skin on the fingers after bathing to an accumulation of water in the stratum corneum of the skin. This process does occur, but it is not responsible for the wrinkles we associate with swimming or leisurely bathing. Wrinkling of the fingers is controlled by the autonomic nervous system via the sympathetic pathways in the sensory nerves. In 1973, O'Riain documented that a laceration of the digital nerves to the fingers will prevent wrinkles from forming on the fingers after any period of immersion. This fact is the basis of a common hand-surgery test (the wrinkle test) to determine nerve integrity in patients who are too young or are otherwise unable to report sensibility in the fingertips. Also, patients with leprosy, severe diabetes, or other severe peripheral nerve disorders are unable to form wrinkles in their fingers. Presumably the sympathetic reflex pathways act to cause contraction of the small muscle fibers that are attached to the deep skin layer and act to pull the fingertip skin into noticeable folds.

Gregory Borah, M.D.
Chief of Plastic Hand Surgery
Robert Wood Johnson Medical School
New Brunswick, New Jersey

Richard Sontheimer responds: Many dermatologists attribute water-related wrinkling of the skin on the fingers primarily to excessive hydration of the stratum corneum. Although the magnitude of this effect is not well documented, the role of the nervous system is even more ambiguous. There are published data supporting the idea that sympathetic nerve response can cause some such wrinkling, but this effect appears to be just one of several contributing factors. Some researchers have pointed out that children with cystic fibrosis—who have aberrations in the function of their autonomic nervous system—experience premature wrinkling after water immersion, not the delayed wrinkling one might expect. And while researchers have observed decreased water-related skin wrinkling in patients with diabetes, this phenomenon appears to be independent of the state of the patient's autonomic nervous system. It may be related to the well-recognized changes in thickness and rigidity of the skin of diabetics.

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