Exhaled volatile organic compounds (VOCs) are of interest for their potential to diagnose disease non-invasively. However, most breath VOC studies have analyzed single breath samples from an individual and assumed them to be wholly consistent representative of the person. This provided the motivation for an investigation of the variability of breath profiles when three breath samples are taken ...

Over the last few years, breath analysis for the routine monitoring of metabolic disorders has attracted a considerable amount of scientific interest, especially since breath sampling is a non-invasive technique, totally painless and agreeable to patients. The investigation of human breath samples with various analytical methods has shown a correlation between the concentration patterns of vola...

Non-invasive breath tests can serve as valuable diagnostic tools in medicine as they can determine particular enzymatic and metabolic functions in vivo. However, methodological pitfalls have limited the actual clinical application of those tests till today. A major challenge of non-invasive breath tests has remained the provision of individually reliable test results. To overcome these limitati...

The selected ion flow tube technique was used to quantify in breath the trace gases acetone, ammonia, ethanol, isoprene, and methanol during single exhalations while fasting and in response to feeding. Six normal volunteers were fasted for 12 h, and, after baseline breath samples were obtained, were fed a liquid protein-calorie meal to provide 0.47 g/kg of protein (Fortisip). Further breath sam...

Methods A group of 7 healthy volunteers were instructed to hyperventilate for 1 and 2 minutes followed by a long free breath hold. A second group of 5 aquatic athletes performed a 60s breath hold and a free maximal breath hold. BOLD-sensitive SSFP cines were acquired during breath holds as well as before and after hyperventilation. Changes in signal intensity over the procedures were expressed ...

Purpose Many sick adults and children are unable to perform long breath-holds required for conventional, Cartesian phase-contrast (PC) sequences. Using a prospectivelytriggered spiral PCMR sequence accelerated with sensitivity encoding (SENSE), it should be possible to achieve high resolution PCMR data in a short breath-hold. The aim of this study was to compare flow volumes measured using: a) ...

Alter Breath-hold duration Increasing parallel-imaging factors (up to x 4 routinely) will reduce breath-hold with minimal impact on SSFP quality. Reduce spatial resolution small reductions in phase resolution will significantly reduce breath-hold Increasing the echo train/segments shorten breathhold, with slight decrease in temporal resolution Increase the number of averages(3-5) for free-breat...

For medicolegal purposes, breath alcohol content is typically determined from an end-expiratory sample. Measurements obtained by this method necessarily underestimate the alveolar breath alcohol content, and therefore underestimate the blood alcohol content. We suggest and analyse an improved paradigm which uses the entire time-series of breath alcohol measurements during exhalation, not simply...

Breath tests are among the least invasive methods available for clinical diagnosis, disease state monitoring, and environmental exposure assessment. In recent years, interest in breath analysis for clinical purposes has increased. This review is intended to describe the potential applications of breath tests, including clinical diagnosis of diseases and monitoring of environmental pollutant exp...

Background: Pathogenic yersiniae (Y. pestis, Y. pseudotuberculosis, Y. enterocolitica) share a virulence plasmid encoding a type three secretion system (T3SS). This T3SS comprises more than 40 constituents. Among these are the transport substrates called Yops (Yersinia outer proteins), the specific Yop chaperones (Sycs), and the Ysc (Yop secretion) proteins which form the transport machinery. T...