Skin Cancer Risk and Asian Sand Vipers

• A protein called eristostatin has been extracted from the venom of the Asian sand viper that suppresses the spread of malignant melanoma cells. Melanoma is an aggressive kind of skin cancer that can spread to other organs of the body. The protein is apparently attracted to certain receptors of the surface of melanoma cells. When attached to the cancer cells, the protein attracts the attention of immune cells that move in and destroy the cancer cells. (The Economist, Jan. 5, 2013)

• Skin cancer is the most common form of cancer in the U.S.—one person dies of this kind of cancer every hour. A person’s risk for melanoma doubles if he or she has had more than five sunburns at any age. And one or more blistering sunburns in childhood or adolescence more than doubles a person’s changes of developing melanoma later in life. (www.skincancer.org)

• Under proper conditions, stem cells can specialize into many kinds of body tissue. These cells are equivalent to undifferentiated embryonic cells, and the best source of undifferentiated human stem cells is an early human embryo. Because obtaining stem cells from human embryos raises ethical questions, researchers sought other ways to produce human stem cells. In 2007, two research groups managed to convert adult skin cells into stem cells by introducing four activated genes into their nuclei. Now several drug companies hope to coax such stem cells into heart muscle, blood vessels, and nerve and liver cells. Once these cells grow into specialized cells in culture dishes, they can be used for drug toxicity studies. It is possible they can also be used in the case of Parkinson’s Disease, where cultured cells of stem cell origin can be transplanted into the brain to become nerve cells lost as the disease progresses. (The Economist, Jan. 2013)

• Australian researchers recently reported that dragonflies share a behavior previously described only for primates, that of selective attention. This means that a dragonfly has the “mental” ability to screen out useless visual information as it focuses, and remains focused, on a target. When a dragonfly encounters a swarm of prey insects, such as deerflies, flying ants, or mosquitoes, it flies in and around the swarm as it focuses on one prey insect to follow, capture, and eat. Once locked onto the target, aerobatic flight allows it to follow and devour the prey, in spite of other insects and distractions (such as other dragonflies) all around them. The researchers followed such flights and said dragonflies get their prey 97% of the time. The same researchers used a glass probe with a tip 1,500 times smaller than a human hair and were able to detect the specific group of neurons in the dragonfly’s brain responsible for targeting prey. (Weiderman and O’Carroll, Current Biology, Dec. 20, 2012; http://www.msnbc.msn.com/id/50307990/technology)