Condensation of water vapor in the exhaled air stream as it passes over previously cooled membranes of the nasopharynx is thought to be a mechanism that reduces respiratory water loss in mammals and birds. Such a mechanism could be important in the overall water economy of these vertebrates, especially those species occupying desert habitats. However, this hypothesis was originally based on mea...

This paper is associated with a video winner of 2020 American Physical Society's Division Fluid Dynamics (DFD) Milton van Dyke Award for work presented at the DFD Gallery Motion. The original available online Motion, https://doi.org/10.1103/APS.DFD.2020.GFM.V0067.

BACKGROUND Nitric oxide (NO) is released by activated macrophages, neutrophils, and stimulated bronchial epithelial cells. Exhaled NO has been shown to be increased in patients with asthma and has been put forward as a marker of airways inflammation. However, we have found that exhaled NO is not raised in patients with cystic fibrosis, even during infective pulmonary exacerbation. One reason fo...

BACKGROUND Nitric oxide (NO) is involved in inflammation and host defence of the lung. It has been found in increased concentrations in the airways in asthmatic subjects but its levels in patients with chronic obstructive pulmonary disease (COPD) have not been investigated. A study was undertaken to determine whether markers of NO metabolism (NO in exhaled air, iNOS expression in sputum cells, ...

The importance of interaction of exhaled air with the airway surface was evaluated by comparing the effects of different breathing maneuvers and inhaled air temperature on the relationship between breath alcohol concentration (BRAC) and blood alcohol concentration (BAC). Breath alcohol was measured with an infrared absorption unit. Blood and simulator liquid alcohol concentrations were measured...

Exhaled breath condensate (EBC) may be an attractive noninvasive alternative to bronchoscopy, bronchoalveolar lavage and induced sputum for diagnosis and monitoring of pulmonary disease. The aim of the present study was to identify proteins in EBC by mass spectrometry. Protein in EBC was characterised by gel electrophoresis of freeze-dried EBC samples, and individual proteins were identified by...

Testing for drugs of abuse in sample matrices alternative to urine such as blood, sweat, and saliva have received increasing attention and is needed, for example, in traffic medicine. Human breath is known to contain a large number of substances including non-volatile molecules. We explore whether intake of amphetamines could be detected by analytical investigation of exhaled breath from drug a...

An increased concentration of nitric oxide (NO) in the exhaled air of asthmatic patients may reflect inflammation of the airways, and exhaled NO may, therefore, be useful in monitoring asthma control and the optimal use of anti-inflammatory treatment. We have studied the effect of reducing and then increasing the dose of inhaled steroid on exhaled NO, lung function and symptoms in 14 asthmatic ...

BACKGROUND Exhaled breath contains thousands of gaseous volatile organic compounds (VOCs) that may be used as non-invasive markers of lung disease. The electronic nose analyzes VOCs by composite nano-sensor arrays with learning algorithms. It has been shown that an electronic nose can distinguish the VOCs pattern in exhaled breath of lung cancer patients from healthy controls. We hypothesized t...