(DOWNLOAD) "Breath Analysis: Potential for Clinical Diagnosis and Exposure Assessment." by Clinical Chemistry * Book PDF Kindle ePub Free
eBook details
- Title: Breath Analysis: Potential for Clinical Diagnosis and Exposure Assessment.
- Author : Clinical Chemistry
- Release Date : January 01, 2006
- Genre: Chemistry,Books,Science & Nature,
- Pages : * pages
- Size : 228 KB
Description
Physical, biochemical, and molecular biological methods for medical monitoring and diagnostics have rapidly developed in recent decades. The major developments in medical monitoring technologies and diagnostic methods have focused on blood and urine analysis for clinical diagnostics. Relatively, diagnostics based on breath analysis are much less developed and not yet widely used in clinical practice (1). Although a few types of breath tests have been successfully used as diagnostic tools in clinical analyses, such as the [[sup.13/14]C]urea breath test (UBT) (1) in the diagnosis of Helicobacter pylori infection (2-4) and the NO breath test in the diagnosis of airway inflammation (5-7), breath analysis could have many more potential applications in the clinical diagnosis of disease and monitoring of exposure to environmental pollutants. The bulk matrix of breath is a mixture of nitrogen, oxygen, C[O.sub.2], [H.sub.2]O, and inert gases. The remaining small fraction consists of more than 1000 trace volatile organic compounds (VOCs) with concentrations in the range of parts per million (ppm) to parts per trillion (ppt) by volume (5, 8-10). In terms of their origin, these volatile substances may be generated in the body (endogenous) or may be absorbed as contaminants from the environment (exogenous). The composition of VOCs in breath varies widely from person to person, both qualitatively and quantitatively. Phillips et al. (8) systematically assayed the VOCs and their variations in the breath of healthy humans. Although the number of VOCs found to date in human breath is more than 1000, only a few VOCs are common to all humans. These common VOCs, which include isoprene, acetone, ethane, and methanol, are products of core metabolic processes and are very informative for clinical diagnostics (10). The bulk matrix and trace VOCs in breath exchange between the blood and alveolar air at the blood--gas interface in the lung. One exception is NO, which is released into the airway in the case of airway inflammation.