Grocery store tomatoes began to taste funny back in the 1960s, when scientists created the first hybrids designed to stay fresh longer. The hybrids were a quick commercial hit, yet flavor lost out. To survive transport, stay-fresh tomatoes must be harvested while still green and firm, then ripened en route using nontoxic chemicals. So they never develop the delicate sugars or acids of vine-ripened tomatoes. Bioengineers tried to solve the problem in the early 1990s with the Flavr Savr tomato, but consumers balked at the still so-so taste.
Better winter salads may at last be at hand. Scientists at the Boyce Thompson Institute for Plant Research Inc. in Ithaca, N.Y., and the U.S. Agriculture Dept. have identified a "master key" gene that controls the ripening process in tomatoes and some other flowering plants. By tweaking this DNA sequence, team leader Jim Giovannoni, a project scientist at both BTI and the USDA, aims to achieve the Holy Grail of tomato-dom: a fruit that can vine-ripen but stay sturdy enough to transport.
The discovery may improve more than just tomatoes, says Jocelyn K.C. Rose, a professor of plant biology at Cornell University. Other fragile produce, including bananas, bell peppers, melons, and strawberries, could benefit, too. In the hunt for new drugs, researchers often come up with promising candidates only to find they're not soluble. That makes it hard to deliver the compound safely and effectively. By some counts, half of all chemicals discovered in the lab never make it any further for that reason alone.
Scientists at Baxter International, however, say they have found a way to turn that dead end into an entrance ramp. The secret? Miniaturization. To be taken intravenously, drug particles must be soluble and less than one micron in diameter. But even many small-molecule drugs form crystals 10 to 20 times that size. With the aid of patented "microprecipitators," Baxter scientists have been able consistently to produce very tiny particles, which can be homogenized to produce crystals one-quarter micron in size. The scientists then coat the tiny crystals so they do not clump back together and can be time-released once in the body.
Baxter is testing two drugs in animals and doing earlier-stage work on four others. It's also talking with big pharmaceutical companies about using the process to salvage compounds that have stumbled in clinical trials. Baxter plans to make injectable medications first but may use the technology later to make oral or inhaled drugs. Baxter says approvals from the Food & Drug Administration may be four years away. Here's further proof that women are from Venus and men from Mars. Researchers at the University of Minnesota Heart Institute Foundation report that emotional stress is more likely to trigger sudden cardiac arrest in women than physical exertion. But for men, the opposite is true.
The scientists studied 102 men and 20 women who had suffered cardiac arrest, which occurs when the heartbeat becomes so rapid that the organ stops working. It can lead to death within minutes. The patients in the study were asked to fill out detailed questionnaires about their activities prior to their attack. The results: 40% of the women said they were experiencing psychological stress at the time, and only 5% reported physical exertion. Among the men, however, 40% reported physical stress, while 16% were suffering from emotional stress. Dr. Norman B. Ratliff, a cardiologist at the Foundation, told an American Heart Assn. scientific meeting in Honolulu that the mechanism of sudden death may begin on a different biological pathway for women than for men. He also noted that half of the women had no prior symptoms, compared with one-third of the men. -- Lightning does strike twice in the same place. In fact, in the first worldwide survey of lightning patterns, researchers from NASA and the National Space Science & Technology Center in Huntsville (Ala.) have found a surprising regularity to the distribution of the super-bright bolts. Satellite data from as far back as 1995 show that regions where huge air masses routinely clash breed the most lightning shows. The top hot spots include Central Africa, the Himalayas, and the coasts of Florida. The most lightning-free zones are the North and South Poles. Next up: more sensitive lightning-detection gear will identify dangerous weather patterns over the U.S. as they develop.
-- Air travel could become safer and a bit quicker if a new system that tests boarding passes for explosive residues is put into use. The unit, being developed by Oak Ridge National Laboratory (ORNL) and Britain's Mass Spec Analytical Ltd., could replace existing procedures, in which inspectors swab the luggage and hands of selected passengers, then check for chemical bomb traces using a desktop ion-mobility spectrometer. ORNL's alternative turbocharges inspection by means of a faster, more sensitive mass spectrometer to sample every traveler's boarding pass. Plus the unit generates fewer false results, says ORNL's Gary Van Berkel. Pre-production units are being tested.