Fever seems to improve behavior

AUTISM
When we think of fever, our first thought is of illness. But a new observational study from the Kennedy Krieger Institute in Baltimore suggests that children with autism who develop a fever often have improved behavior while they have a temperature. Autism is a neurodevelopmental disease that is rising in incidence - nearly 1 in 150 children are diagnosed with the illness. Researchers first became interested in the link between autism and fever after parents began to provide anecdotes of their children exhibiting improved behaviors when they had a temperature. To study this observation systematically, lead researcher Dr. Andrew Zimmerman, examined 60 autistic children over a two-year period, half of whom developed fevers and half who remained fever-free, and studied whether fever impacted behaviors characteristic of autism, such as inattention, disruptive activity, self-injury, and repetitive speech. While they were feverish, the children's attention span, language, and hyperactivity improved significantly compared to children without a fever. Why fever should improve behavior isn't clear, but it may have something to do with cytokines - chemicals released into the blood during a fever response - which may affect the way cells in the brain communicate.

BOTTOM LINE: Fever seems to improve the symptoms of autism - providing clues into understanding how the cells in the brain malfunction in the autistic patient.

CAUTIONS: The study's sample size was relatively small. Future studies will help to refine the observations made here.

WHAT'S NEXT: "We plan on performing some blood tests during fever to look for changes in cytokines and other chemicals" in an effort to uncover the biology behind this phenomenon, Zimmerman said.

WHERE TO FIND IT: Pediatrics, Dec. 3
SUSHRUT JANGI

Biology

Regenerating tissues is a common feat among many creatures in the animal kingdom; when one of these animals loses its head or tail, it simply grows a new one. But how does the creature know to grow a head instead of a tail? Two teams of biologists at Whitehead Institute for Biomedical Research and the University of Utah School of Medicine may have found the answer to this centuries-old question - called regeneration polarity - at least in one animal: the planarian flatworm. Widely regarded as a good model for regeneration, planarians can regrow a head or tail in less than a week. The organism shares more than 50 percent of its genome with other animals, including the evolutionary preserved Wnt signaling pathway, a key player in many body functions found in every animal ever studied. The two research groups, one led by Peter Reddien at Whitehead and the other by Alejandro Sanchez Alvarado in Utah, have found that manipulating a protein called Beta-catenin involved in Wnt signaling determines whether the worm grows a new head or tail. A decrease in Wnt signaling resulted in the regeneration of heads, while an increase produced new tails.

BOTTOM LINE: "One of the basic questions asked by anyone - from elementary school students to biology professors - looking at a regenerating planarian is: After amputation, how does a piece of the animal 'know' whether to make a head or a tail?" says Phillip Newmark, a biologist at the University of Illinois at Urbana-Champaign not affiliated with either study. "This work provides an entry point for answering this fundamental question."

CAUTIONS: Though the Wnt pathway is found throughout the animal kingdom, it's not clear what role it plays in tissue regeneration in other animals.

WHAT'S NEXT: "We know that some switch is thrown at wound sites that specifies anterior-posterior polarity, and this is the switch in planarian," Reddien said. "The next step will be to look at how the switch works."

WHERE TO FIND IT: Science Express Online, Dec. 6
KELLI WHITLOCK BURTON