Early warning

Geddes, who heads a panel that advises Edmonds on research grant applications, does not apologise for bragging. He says his system8212;known as Microwave Accelerated Metal Enhanced Fluorescence8212;could generate a wide range of medical detectors, such as test kits to check for avian bird flu, anthrax or toxic shock. 8216;8216;Potentially it could save a lot of lives,8217;8217; said Geddes. Other experts are more cautious. Said Robert H. Christenson, a pathologist at the University of Maryland School of Medicine and an authority on the body8217;s internal responses to heart attack: 8216;8216;I8217;m enthusiastic about it. I just don8217;t want to see it hyped.8217;8217;

For heart attacks, Geddes envisions a device similar to the test kits used by diabetics who draw blood with a finger prick and insert the blood in a pen-sized tube to monitor their glucose levels. 8216;8216;The technology for delivering the system already exists. It8217;s just a matter of adapting it,8217;8217; Geddes said. 8216;8216;But it8217;s inevitable that it8217;s going to take some time.8217;8217;

Geddes8217; specialty is fluorescence spectroscopy, a method of determining the presence of different compounds8212;in blood, tissues and other substances8212;by the colours emitted when a sample is exposed to different light wavelengths. One breakthrough for Geddes and UMBI researchers came four years ago, when they found that pre-treating the samples they were testing with silver, gold and other metals improved the effectiveness of the spectroscope. More recently, Geddes and a UMBI colleague, Kadir Aslan, found that heating a blood or tissue sample speeds up the detection of certain biomarkers, such as those signalling heart attacks. They published their findings in November in Analytical Chemistry

When a heart attack kills heart cells, they release a chemical called troponin into the bloodstream. Hospitals commonly test for troponin and other biomarkers, as they are known, to determine whether a patient has had a heart attack. An initial electrocardiogram ECG, which measures heart rhythm, can sometimes determine whether someone experiencing chest pains has had a heart attack. But in 50 percent to 70 percent of all cases, an ECG is inconclusive, so doctors look for troponin levels and other biomarkers in the blood. However, because it takes time for troponin to accumulate in the blood stream, tests for troponin are usually conducted at timed intervals over six to eight hours.

Geddes said his system can identify troponin and another biomarker for internal injuries, known as myoglobin, at previously undetectable levels. Drawing and testing the blood takes less than 20 seconds, he said.

The longer a heart attack goes untreated, the greater the likelihood of long-term damage to vital heart muscles. However, because heart medications carry their own risks, doctors treat patients for heart attack only after it has been diagnosed, meaningmeans earlier diagnosis could save more lives.

LAT-WP