Pickens writes: "US News and World Reports reports that the needle pricks involved in acupuncture may help relieve pain by triggering a natural painkilling chemical called adenosine, and that acupuncture's effectiveness can be enhanced by coupling the process with a well-known cancer drug — deoxycoformycin — that maintains adenosine levels longer than usual. Working exclusively with mice, Dr. Maiken Nedergaard, co-director of the Center for Translational Neuromedicine at the University of Rochester Medical Center and her colleagues administered half-hour acupuncture treatments to a group with paw discomfort. The investigators found adenosine levels in tissue near the needle insertion points was 24 times greater after treatment, and those mice with normal adenosine function experienced a two-thirds drop in paw pain. By contrast, mice that were genetically engineered to have no adenosine function gained no benefit from the treatment. However many remain skeptical of acupuncture claims. Ed Tong writes in Discover Magazine that previous clinical trials have used sophisticated methods to measure the benefits of acupuncture, including “sham needles”, where the needle’s point retracts back into the shaft like the blade of a movie knife to determine if the benefits of acupuncture are really only due to the placebo effect. "Last year, one such trial (which was widely misreported) found that acupuncture does help to relieve chronic back pain and outperformed “usual care”. However, it didn’t matter whether the needles actually pierce the skin, because sham needles were just as effective," writes Tong. "Nor did it matter where the needles were placed, contrary to what acupuncturists would have us believe.""