From Male Baldness to Scorpionfish

• A recent study showed that balding men have high amounts of a molecule called prostaglandin D2 in the hairless part of their scalp (let’s refer to the molecule as “D2”). The part of the scalp that retains hair shows low amounts of the molecule. Could the presence of high amounts of D2 be a clue to hair loss? Further studies showed that follicle stem cells, which normally bring about hair growth, are present but inactive in bald patches. It was as if the stem cells were blocked from becoming cells that actively grew hair. After a number of studies it was discovered that when the level of D2 increases in the scalp, the molecules bind to the surface receptors of follicle stem cells and turn “off” their ability to grow hair. If a treatment could be devised that inactivates D2 receptors, the bald portion of the scalp could be induced to grow new hair. In other words, follicle stem cells would be turned “on.” Efforts are now underway to achieve this goal. As is often the case in science, the study answers one question but raises several more. Why does the level of prostaglandin D2 rise in the first place? And what role does testosterone play in the process, for this hormone also plays a role in male baldness. (Cotsarelis et al, 1912, in Science Translational Medicine, March 21; Science News, April 21, 2012)

• When researchers tested the blood levels of vitamin D in 3,000 men between the ages of 40 and 79 and assessed their cognitive (mental) ability, they found that subjects with low levels of vitamin D did poorly on mental tests compared to those with higher levels. Vitamin D is supplied by exposure to sunlight and the consumption of foods such as oily fish, fortified dairy products, egg yolk, and liver. (Mind, Mood & Memory, Mass. General Hospital, 2010)

• Does the Gulf Stream really warm Europe? It has long been known that some combination of wind and ocean currents makes for milder European winters than in states of North America on the same latitude. Research has shown that the warm waters of the Gulf Stream benefit Scandinavia, while warm prevailing winds are responsible for mild winters in the rest of Europe. What happens is that winds from the southwest pick up heat from the waters of the Atlantic; these winds, combined with a minor effect by the Gulf Stream, result in British winters being 15 to 20 degrees F warmer than Labrador’s. (ScienceNOW, Sept. 26, 2002)

• A group of venomous fish, known collectively as scorpionfish, are not only ugly but also deadly. They have grooved spines on their back and fins that carry venom from a sac at the base of the spines. Their bodies are decorated with knobs, tassels, and colored patches that help them blend into their surroundings. Lionfish are one type of scorpionfish. Native to the Indian and Pacific Oceans, they were accidentally introduced into Atlantic and Caribbean waters in the 1990s, where they have no natural predators. Lionfish reach a length of 12 to 15 inches, and their rapid growth around Florida is now threatening fish populations, for they devour juvenile grouper, snapper, and the young of other commercial species. Many commercial lobster fishermen are complaining that their traps are filling up with lionfish rather than lobsters. Now officials are hoping that chefs will create recipes using lionfish and that restaurants will begin to feature them on their menus. This would create a market that might deplete the population. The fish are apparently quite tasty, and cooking them neutralizes the poison in their spines. It is best, however, to encounter a lionfish on a plate rather than in the ocean, because humans stung by these fish experience intense throbbing pain and may have to be taken to a hospital emergency room and treated for shock. (www.cnn.com/2012/04/24; http://www.reef.org)