DEET, bunions and odiferous cancer

Here's a few recent items hot off sundry lab benches:

--At UC Davis, scientists acertained how DEET works: Apparently, mosquitos can't stand the stuff. The news is published in the journal Proceedings of the National Academy of Sciences as a paper entitled "Mosquitos smell and avoid the insect repellant DEET."

It may seem obvious that a repellent should be repellent, but in fact, the "smells nasty" DEET theory overturns another, long-held one--that mosquitos refrain biting around DEET because it interferes with their ability to properly smell and home in on the succulent arms and legs of picnickers and hikers.

--People who've had bunions removed are safe behind the wheel 6 weeks after the operation, according to a study in the Journal of Bone and Joint Surgery. Scientists at the Glasgow Royal Infirmary in the UK ascertained this by measuring emergency brake time response using a driving simulator of 28 patients who'd gotten a common bunion surgery called a first metatarsal osteotomy. The study found that at six weeks the reaction times matched those of people of similar age and driving experience, but healthy feet.

--Skin cancers carry a distinctive odor. This may be why some dogs can reputedly sniff cancers. (On a side note, you may be interested to know that a Japanese cancer-sniffing dog, Marine, is reportedly being cloned.) Scientists at the Monell Chemical Senses Center in Philadelphia sampled the air above a type of skin cancer called a basal cell carcinoma in 11 patients and compared it to the air over similar areas of skin on 11 healthy patients. They found a changed pattern of so-called volatile organic compounds, organic molecules that waft easily into the air, in the cancer samples--amounts of certain chemicals were increased relative to healthy samples while others were decreased.

--Rosie Mestel

Photo by Robert Durell/L.A. Times