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LEFT AND RIGHT: A wild type st 45 Xenopus embryo with rightward heart looping and counter-clockwise gut coiling is shown on the left. In contrast, a st 45 embryo that was injected with Pitx2 at the 4 cell stage exhibits leftward heart looping and clockwise gut coiling. When it comes to organ orientation, one gene can make the difference between right and left. That gene, Pitx2 , has been identified as the key to asymmetry, or "handedness," the property describing on which side of the body the

Chimpanzees share almost all their gene sequences with humans, and this closeness has made them ideal animal models for many human diseases. But similarities between humans and nonhuman primates go beyond genetics. Nonhuman primates are very social animals, travel long distances to find food, sometimes live on the fringes of the wild, and often become afflicted with diseases closely resembling those of humans. PREP FOR FLIGHT: Handlers prepare chimpanzee Ham, one of the NASA "astrochimps," f

It was fitting, perhaps, that Cumulina the cloned mouse made her debut at a press conference in New York City on Gregor Mendel's birthday, July 22. As the father of genetics, Mendel explained genetic variability. As the first mouse cloned from an adult's cell nucleus, Cumulina represents the ultimate in genetic uniformity. So far, 50 mice have been cloned, some through three generations. Photo: ProBio America Inc. THREE GENERATIONS: Researchers at the University of Hawaii cloned these three g

Although these three alternatives to injections don't look alike, the mechanisms by which they protect against diseases have much in common. 

Recent research has shed new light on the sleep/wake cycle. In two papers featured on the cover of the July 10 issue of Cell (J.L. Price et al., Cell, 94:83-95, 1998; B. Kloss et al., Cell, 94:97-107, 1998), scientists from Rockefeller University reported the discovery of a gene in Drosophila, dubbed double-time (dbt). The dbt gene is believed to regulate the molecular cycles underlying circadian rhythms--patterns of activity that, in humans, regulate body temperature, mental alertness, pain

Rita Colwell GOOD-BYE ... ALMOST On July 10, University of Maryland bid a bittersweet "almost farewell" to Rita Colwell, who left the position of president of the university's Biotechnology Institute (UMBI) to become director of the National Science Foundation (NSF). Colwell's farewell to UMBI is only partial--she has committed herself to one day of research per week in her laboratory, where she studies, particularly, the bacteria that cause cholera. On hand July 10 to congratulate her and wi

Theoretically, scientists should be able to deliver antigens against E. coli, cholera, or other diarrhea-causing pathogens in just about any fruit or vegetable. But practicality may trump technology when it comes to picking how to package an edible vaccine. 

Pediatric vaccinations make children's skin resemble pincushions. Transcutaneous immunization methods in development aim to make their skin function like sponges. Harnessing the adjuvant activity of cholera toxin (CT) could make this immunization method feasible, predicts Gregory M. Glenn, scientific director of IOMAI Inc., a biotech company in Washington, D.C. Glenn and colleagues are developing a technique that mixes the toxin with antigens to boost immune responses. In one set of experimen

The eyes may be windows to the soul, but the nose is a gateway to the mucosal immune system. Drug companies are now developing vaccines to take advantage of that gateway. Courtesy of Aviron MISTING UP: Aviron's nasal flu vaccine, which has recently completed Phase III trials, targets the mucosal system and protects against both flu and ear infection. "If you can stimulate the mucosal immune system--that's the majority of the immune system," explains Larry G. Stambaugh, president and CEO of M

About ten years ago Antonia Demas, a self-described "middle-aged woman,'' returned to graduate school after raising a family, intending to develop the work she had been doing informally for many years. Volunteering in an elementary school in Trumansburg, N.Y., near Ithaca, she had used food and cooking in the classroom as teaching tools, and she proposed to explore ways of tying the school lunch program to the academic curriculum and improving education about nutrition. She has now become embro

SEALED AND DELIVERED: Pasteurized Eggs has won USDA's first seal certifying the efficacy of the process for making eggs nearly Salmonella-free. The difference between pasteurized and unpasteurized eggs from the shell is hardly visible. The pasteurized ones (top) are slightly cloudier. Eggs, sunny-side up, have been on the path to becoming a relic of the past. Salmonella enteritidis (SE) has become one of the most common causes of bacterial foodborne illness in humans in the United States, an

Four years after its discovery, the weight-controlling protein hormone leptin is still making news. At the American Diabetes Association meeting in Chicago June 14, researchers from Amgen Inc. of Thousand Oaks, Calif., announced promising results of a Phase I clinical trial of leptin. And more than 100 papers and posters featured leptin at the Endocrine Society's annual meeting in New Orleans, June 24 to 27. Much of the excitement, though, lies beyond leptin, with the other players in the sign