Research published simultaneously in PNAS and Nature details how scientists have successfully transplanted most of the "nose" of the mosquito that spreads malaria into frog eggs and fruit flies and are employing these surrogates to combat the spread of the deadly disease that afflicts 500 million people worldwide. The mosquito's "nose" is centered in its antennae, which are filled with nerve cells covered with special "odorant receptors" that react to different chemical compounds. The insect ORs are comparable to analogous receptors in the human nose and taste buds on the tongue.
California's coastal fog is decreasing significantly and may endanger redwood trees along the coast dependent on cool, humid summers, according to a new study to be published in PNAS. It is unclear whether this is part of a natural cycle of the result of human activity, but the change could affect the entire redwood ecosystem.
The results came from analysis of new records recently made available by the National Climate Data Center. The U.S. Surface Airways data come from airports around the country, which have recorded for more than 60 years hourly information such as cloud cover (cloud ceiling height), visibility, wind and temperature.
Human cells contain 46 strands of DNA that code for all our genes. Certain chemicals and UV light can break these strands into pieces, a process that typically leads to cell death or diseases such as cancer if the damage is not repaired quickly. But new research, published in PNAS, shows for the first time that stem cells will intentionally cut and then repair their own DNA as a mechanism of activating genes that promote the development of new tissues.
The discovery could help researchers develop better ways to activate stem cells, so that they can produce new tissues for therapeutic purposes. It also suggests that DNA mutations, which can contribute to a variety of diseases, may initially occur as a result of a normal cellular process.
Researchers from the University of Illinois say they know how to exploit an unusual chemical reaction mechanism that allows malaria parasites and many disease-causing bacteria to survive. The findings, detailed in PNAS, could eventually lead to new anti-malarial and antibacterial drugs.
The new study focused on an essential chemical pathway that occurs in malaria parasites and in most bacteria but not in humans or other animals, making it an ideal drug target. Several teams of researchers have spent nearly a decade trying to understand an important player in this cascade of chemical reactions, an enzyme known as IspH. This enzyme promotes the synthesis of a class of compounds, called isoprenoids, which are essential to life.
A surprising new study in the Journal of Clinical Sleep Medicine reveals that sleepiness at the wheel and poor sleep quality significantly increase the risk of motor vehicle accidents for teenage drivers.
Results indicate that adolescent drivers were twice as likely to have had a crash if they experienced sleepiness while driving (adjusted odds ratio = 2.1) or reported having bad sleep (OR = 1.9). Eighty of the 339 students had already crashed at least once, and 15 percent of them considered sleepiness to have been the main cause of the crash. Fifty-six percent of students who had at least one previous crash reported driving while sleepy, compared with 35 percent of subjects who had not been in a crash.
Infants averaging six months of age who exhibited positional plagiocephaly (flat head syndrome) had lower scores than typical infants in observational tests used to evaluate cognitive and motor development, according to a new study in Pediatrics. Positional or deformational plagiocephaly may occur when external forces shape an infant's skull while it is still soft and malleable, such as extended time spent lying on a hard surface or in one position. Researchers say the findings suggest that babies with plagiocephaly should be screened early in life for possible motor and cognitive delays.
