Written on Monday, September 10, 2007 by Gemini
Scientists are coming up with new ways to diagnose patients before the symptoms show; research could help in early detection of cancer, heart disease and other disorders…
Researchers in the US have established a technique that provides a new approach for detecting a number of genetic disorders found in infants and young children. Daniel Raftery, a professor of analytical and physical chemistry at Purdue University, and his collaborators used a simple chemical reaction to improve the ability to detect important molecules in complex fluids like blood and urine.
The technique makes the markers for some genetically caused metabolic disorders up to 100 times more visible, Raftery said. “This technique allows us to profile a class of biomarkers – molecules that indicate disease – that would otherwise be very difficult to detect,” he said. “The increased sensitivity could allow doctors to diagnose a range of diseases at very early stages.”
This method of analysis, called metabolomics, involves the simultaneous analysis of multiple small molecules, or metabolites, which occur in fluids and tissues in the body. These can indicate a response to biological stress or a specific disease state. “The metabolic profile found in biofluids, such as blood and urine, provides a snapshot of ongoing biological processes in the human body,” Raftery said. “This type of analysis could be a key to earlier detection of diseases.”
Just like an MRI
Researchers use nuclear magnetic resonance spectroscopy – a cousin of magnetic resonance imaging (MRI) – to detect hydrogen or carbon atoms to provide insight into the metabolites present. However, this standard approach has its disadvantages, Raftery said. The signals from carbon atoms are very weak and are difficult to detect, while the signals from hydrogen atoms often overlap. In particular, metabolites present in high concentrations overlap those present in low concentrations. Raftery and his team revolutionised this by enhancing the visibility of a certain type of metabolites – amino acids, by chemically tagging the molecules of interest so that they are more easily visible.
Faster and reproducible
In addition to its increased sensitivity, the new testing method requires little pretreatment of the sample and roughly 0.5 millilitres of blood to perform the test. The entire test can be performed in about half an hour, providing a quick turnaround for results and treatment decisions for patients, Raftery said.
“It is a very simple process and would not require much training to perform the tests,” he said. “It is an easily reproducible test that can be done over and over again, which is important to ensure accurate diagnosis. “This approach is applicable to a variety of molecule types and other fluids, and has the potential for additional applications,” he added. “We plan to test more samples and to determine if this methodology proves to be sensitive to cancer and heart disease, as it is for metabolic disorders.”
A blood test for cancer
In another study, British scientists claimed to have developed a blood test that offers the possibility of spotting cancer long before the symptoms appear.
The test successfully detected early signs of breast cancer in some women, and the scientists hope the vital clues will help them to revolutionise cancer prevention by offering cheaper and less invasive screening techniques in the next ten years. The University of Southampton research team studied blood samples collected from 11,000 women over the last 30 years, some of whom later developed cancer. The researchers looked for and spotted significant biomarkers of breast cancer in the samples. An all-purpose cancer blood test could be quicker, cheaper, more accurate and less invasive than other tests.