Lower Breath Research Articles

Residential Proximity to a Major Roadway Is Associated with Features of Asthma Control in Children

BackgroundWhile several studies suggest that traffic-related air pollutants are detrimental for respiratory health, few studies have examined relationships between residential proximity to a major roadway and asthma control in children. Furthermore, a major limitation of existing research is reliance on self-reported outcomes. We therefore determined the spatial relationship between the distance from a major roadway and clinical, physiologic and inflammatory features of asthma in a highly characterized sample of asthmatic children 6–17 years of age across a wide range of severities. We hypothesized that a closer residential proximity to a major roadway would be associated with increased respiratory symptoms, altered pulmonary function and a greater magnitude of airway and systemic inflammation.Methodology/Principal Findings224 children 6–17 years with confirmed asthma completed questionnaires and underwent spirometry, plethysmography, exhaled nitric oxide determination, exhaled breath condensate collection and venipuncture. Residential distance from a major roadway was determined by mapping the geographic coordinates of the residential address in Geographic Information System software. The distance between the home address and the nearest major roadway was calculated according to the shortest distance between the two points (i.e., “as the crow flies”). Asthmatic children living in closer proximity to a major roadway had an increased frequency of wheezing associated with increased medication requirements and more hospitalizations even after controlling for potential confounders. These children also had increased airway resistance, increased airway inflammation reflected by a lower breath condensate pH, and higher plasma EGF concentrations.Conclusions/SignificanceThese findings suggest that closer residential proximity to a major roadway is associated with poorer asthma control in school-age children. Assessment of residential proximity to major roadways may be useful in the clinical evaluation of asthma in children.

Comparison of abdominal bloating severity between irritable bowel syndrome patients with high and low levels of breath hydrogen excretion in a lactulose breath test

There is growing evidence that gut flora plays a role in the development of Irritable Bowel Syndrome (IBS). Abdominal bloating is a common symptom in these patients and the severity of this symptom could be related to the variations in their fermentative profiles, obtained by measuring the levels of breath hydrogen excretion after lactulose ingestion. Our objective was to determine the difference in abdominal bloating severity between IBS patients with high vs low levels of breath hydrogen excretion after lactulose administration. Lactulose breath tests were carried out on IBS patients in our institution between July 2009 and August 2010. Patients were requested to fill out a validated questionnaire to assess the severity of their symptoms. Abdominal bloating severity score was compared among patients with high and low breath hydrogen levels. A total of 234 patients were enrolled. There was a statistically significant difference in the abdominal bloating severity score between groups: 7.0 (5.7-8.0) vs 6.5 (5.0-7.5), p=0.001. The comparison among IBS patients with constipation (IBS-C) in both groups also showed a statistically significant difference: 7.5 (6.0-8.5) vs 5.8 (3.5-7.2), p=0.0051. Those patients with a low level of breath hydrogen excretion after lactulose ingestion presented with significantly greater abdominal bloating than those with a high level of breath hydrogen excretion.

Toward the quantification of the 13CO2/12CO2 ratio in exhaled mouse breath with mid-infrared hollow waveguide gas sensors

Mouse sepsis models are used to gain insight into the complex processes involved with patients suffering from glucose metabolism disorders. Measuring the expiratory release of (13)CO(2) after administering stable labeled (13)C(6)-glucose enables assessment of the in vivo integrity and functionality of key metabolic processes. In the present study, we demonstrate that Fourier transform infrared spectroscopy operating in the mid-infrared spectral regime (2-20 μm) combined with hollow waveguide gas sensing modules simultaneously serving as a miniaturized gas cell and as a waveguide are capable of quantitatively monitoring (13)CO(2) enrichment levels in low volume mouse breath samples.

Does low dose13C-urea breath test maintain a satisfactory accuracy in diagnosing Helicobacter pylori infection?

The standard doses of (13)C-urea in (13)C-urea breath test is 75 mg. To assess the diagnostic accuracy of (13)C-urea breath test containing 25 mg of (13)C-urea comparing with the standard doses of 75 mg in the diagnosis of Helicobacter pylori infection. Two hundred seventy adult patients (96 males, 174 females, median age 41 years) performed the standard (13)C-urea breath test (75 mg (13)C-urea) and repeated the (13)C-urea breath test using only 25 mg of (13)C-urea within a 2 week interval. The test was performed using an infrared isotope analyzer. Patients were considered positive if delta over baseline was >4.0‰ at the gold standard test. One hundred sixty-one (59.6%) patients were H. pylori negative and 109 (40.4%) were positive by the gold standard test. Using receiver operating characteristic analysis we established a cut-off value of 3.4% as the best value of 25 mg (13)C-urea breath test to discriminate positive and negative patients, considering the H. pylori prevalence (95% CI: 23.9-37.3) at our setting. Therefore, we obtained to 25 mg (13)C-urea breath test a diagnostic accuracy of 92.9% (95% CI: 88.1-97.9), sensitivity 83.5% (95% CI: 75.4-89.3), specificity 99.4% (95% CI: 96.6-99.9), positive predictive value 98.3% (95% CI: 92.4-99.4), and negative predictive value 93.0% (95% CI: 88.6-96.1). Low-dose (13)C-urea breath test (25 mg (13)C-urea) does not reach accuracy sufficient to be recommended in clinical setting where a 30% prevalence of H. pylori infection is observed. Further studies should be done to determine the diagnostic accuracy of low doses of (13)C-urea in the urea breath test.

A Randomized Clinical Trial of a Therapeutic Workplace for Chronically Unemployed, Homeless, Alcohol-Dependent Adults

To assess the efficacy of the Therapeutic Workplace, a substance abuse intervention that promotes abstinence while simultaneously addressing the issues of poverty and lack of job skills, in promoting abstinence from alcohol among homeless alcoholics. Participants (n = 124) were randomly assigned to conditions either requiring abstinence from alcohol to engage in paid job skills training (Contingent Paid Training group), offering paid job skills training with no abstinence contingencies (Paid Training group) or offering unpaid job skill training with no abstinence contingencies (Unpaid Training group). Participants in the Contingent Paid Training group had significantly fewer positive (blood alcohol level ≥ 0.004 g/dl) breath samples than the Paid Training group in both randomly scheduled breath samples collected in the community and breath samples collected during monthly assessments. The breath sample results from the Unpaid Training group were similar in absolute terms to the Contingent Paid Training group, which may have been influenced by a lower breath sample collection rate in this group and fewer reported drinks per day consumed at intake. Overall, the results support the utility of the Therapeutic Workplace intervention to promote abstinence from alcohol among homeless alcoholics, and support paid training as a way of increasing engagement in training programs.

S128 Analysis of volatile biomarkers within exhaled breath for the diagnosis of pneumonia

IntroductionWhilst pneumonia is a common condition affecting both medical and surgical patients there is currently no definitive diagnostic test. One novel approach may be through the non-invasive analysis of volatile...

Breath Acetone Concentration Measured Using a Palm-Size Enzymatic Sensor System

A palm-size electrochemical sensor was developed that utilizes an acetone sensitive enzyme system to amperometrically measure the acetone concentration in human breath. A study of dieting individuals showed an increase in breath acetone from baseline to elevated concentrations as the diet progressed, demonstrating the utility of the device as an indication of the rate of fat metabolism. The sensor response current linearly increased with increasing vapor acetone concentration. The sensor was tested using human breath, and the current response was linear from 0.2 to 10 ppm (v/v). Simulated and human breath results were shown to be comparable, and acetone concentrations out to 24 ppm (v/v) were measured. The enzymatic sensor was capable of detecting the low baseline breath acetone concentrations found in nondieting, nonexercising individuals. The correlation of the enzymatic sensor to the gas chromatograph possessed a linear correlation coefficient greater than 0.950 in all cases.

M1082 Validation of a Low Dose Tablet Formulation 13C Urea and Citric Acid Breath Test Employing An Automated Non Dispersive Isotope Selective Infrared Spectroscopy Analyser (HeliFAN/FAN as) for the Diagnosis of Helicobacter pylori Infection in a Scottish Population

M1082 Validation of a Low Dose Tablet Formulation 13C Urea and Citric Acid Breath Test Employing An Automated Non Dispersive Isotope Selective Infrared Spectroscopy Analyser (HeliFAN/FAN as) for the Diagnosis of Helicobacter pylori Infection in a Scottish Population

Feeding Behavior and Habitat Use in a Waterbird Assemblage at a Marine Wetland in Coastal Patagonia, Argentina

Wetlands are critical foraging areas for many waterbird species, and their relatively high productivity often determines the coexistence of several species using food resources for breeding and/or refueling during migration. Between 18 October and 20 December 2000, we gathered information on foraging habitat use and feeding techniques of sixteen waterbirds during the austral spring at Malaspina inlet, Chubut, Argentina. We quantified the utilization by waterbirds of ten foraging habitat types and seven feeding techniques on seven fixed survey stations along the coastline, representing the different coastal habitats of the Malaspina inlet. The waterbird assemblage was structured in three main guilds: shallow water frequenters (three cormorants, two terns, a grebe, and two steamer-ducks), hard habitat peckers (two gulls, an egret, and an oystercatcher) and soft habitat frequenters (two oystercatchers, a sandpiper, and a duck). These differed greatly in their use of habitats and feeding techniques, suggesting clear differences in the use of food resources. Most of the groups defined used almost exclusively one feeding technique or habitat type. This fact and the low resource utilization breath values suggest the existence of a relatively high degree of specialization within this waterbird assemblage.

Healthy African Americans have an Increased Prevalence of Low Exhaled Breath Condensate pH values

Exhaled Breath Condensate (EBC) pH values are used as a marker of disease activity in asthma and other inflammatory conditions. Previous reports of mixed ethnicity cohorts cohorts have shown that only 3-5% of healthy subjects have an EBC pH <6.5.

LBOVI-B-2Describing the catabolism of orally administered 2-13C-uracil in normal and dihydropyrimidine dehydrogenase deficient subjects using a parent/metabolite/breath model

BACKGROUND Dihydropyrimidine dehydrogenase (DPD) deficiency leads to life-threatening 5-Fluorouracil toxicity. We developed a 2-13C-uracil (13C-Ura) breath test (BT) to rapidly screen cancer patients. Deficient patients have low breath 13CO2 concentrations due to reduced catabolism of 13C-Ura to 13C-dihydrouracil (13C-DHU) and 13CO2. AIM Develop a pharmacokinetic (PK) model to simultaneously describe 13C-Ura and catabolite concentrations in plasma and breath from normal and DPD deficient subjects. METHODS Blood and breath samples were collected for 3h after oral 13C-Ura (6 mg/kg) administration to 19 normal and 10 DPD deficient subjects. Plasma 13C-Ura, 13C-DHU, and breath 13CO2 concentrations were quantified. ADAPT II simultaneously fitted parent, metabolite, and breath concentration-time data. Akaike's Information Criterion was used to select the model. RESULTS A one compartment linear absorption/elimination parent/metabolite model with cumulative breath13CO2 elimination described concentration-time data of 13C-Ura, 13C-DHU, and 13CO2. Significant differences in modeled PK parameters between normal and DPD deficient subjects were observed. CONCLUSION This is the first model to simultaneously describe orally administered 13C-Ura disposition in normal and DPD deficient subjects. Bayesian parameter estimation and simulation studies will be used to identify an optimal limited sampling strategy to detect DPD deficiency in patients who aren't candidates for BT screening. (See Table) PK Parameter Normal Subjects (Mean ± SD) DPD Deficient Subjects (Mean ± SD) Mann-Whitney U Test p Value 13C-Ura Half-life (h) 0.18 ± 0.07 0.60 ± 0.67 ≤ 0.001 13C-Ura Clearance (L/kg/h) 1.54 ± 0.63 0.77 ± 0.30 ≤ 0.001 13C-DHU Formation Rate Constant (1/h) 3.23 ± 2.48 1.24 ± 0.64 ≤ 0.001 Clinical Pharmacology & Therapeutics (2005) 79, P83–P83; doi: 10.1016/j.clpt.2005.12.298

Glutathione S-transferase polymorphisms are linked to asthma and low breath condensate pH

RATIONALE: Human glutathione S-transferase (GST's) are a superfamily of proteins that protect against intracellular oxidative stress. We examined the effects of polymorphisms in the GSTM1, GSTT1, and GSTP1 genes on lung function.

Shaping Reduced Smoking in Smokers Without Cessation Plans.

Most smokers do not plan to quit in the next 6 months. The authors previously demonstrated that percentile schedules shape lower breath carbon monoxide (BCO) levels in smokers trying to quit (R. J. Lamb, A. R. Morral, K. C. Kirby, M. Y. Iguchi, & G. Galbicka, 2004). In that study, the authors set reinforcement criteria based on the 9 most recent samples. In this study, the authors examined whether a more responsive procedure using the 4 most recent samples is more effective in smokers not trying to quit. Following institution of the contingencies in both groups, BCO levels were substantially reduced, and readiness to quit and cessation self-efficacy increased. However, more individuals in the 4-sample window group achieved a BCO level below 4 ppm, indicating recent abstinence. These individuals did so more rapidly and for a greater number of visits.

The Effects of Exercise on Markers of Lipid Peroxidation in Renal Dialysis Patients Compared with Control Subjects

The purpose of this study was to compare the susceptibility to exercise-induced lipid peroxidation of patients on chronic maintenance dialysis (CMD) and non-CMD control subjects. Cross-sectional comparison of exercise-induced changes in breath ethane and pentane flux between patients on CMD (group A) and an age-, gender-, medical diagnosis-, smoking-, and ethanol consumption-matched comparison group (group B). Breath ethane and pentane were measured at rest before exercise, during cardiopulmonary exercise stress testing (CPX) at lactic acidosis threshold (Vo2lat), and 5 minutes after CPX. Group comparisons of clinical characteristics reveal that the groups were similar in terms of age, ethnicity, comorbid diagnoses, prevalence of medication use, BMI, measurements of aerobic exercise capacity, cigarette smoking and ethanol consumption behaviors. All subjects successfully completed the CPX protocol achieving Vo2lat. There were significant differences in breath ethane flux between group A and B subjects, with greater pre-exercise, Vo2lat, and postexercise ethane levels in group A compared with group B subjects, and significant group differences, with lower breath ethane/pentane flux ratios at rest, Vo2lat, and recovery with lower ratios in group B than group A subjects. This study shows that patients on CMD have greater lipid peroxidation compared with control subjects at rest and during and after physical exercise. In addition, compared with control subjects, patients on CMD preferentially peroxidize n-3 polyunsaturated fatty acids at rest and during physical exercise and recovery. The lipid peroxidation profile may result in an unfavorable endoperoxide shift and should be evaluated further, along with modalities to reduce oxidative stress among patients on CMD.

Evidence for impaired assimilation of protein in chronic renal failure

Protein malnutrition is a common finding in chronic renal failure (CRF) and is associated with poor outcome. We hypothesized that besides inadequate dietary protein intake and alterations in metabolism, deficient protein assimilation (digestion and absorption) might contribute to the pathogenesis of protein malnutrition in uremia. Protein assimilation was evaluated in 64 healthy volunteers and 119 CRF patients by means of a 13C protein breath test and/or quantification of p-cresol in a 24-hour urine collection. Both approaches provide reliable information on the efficiency of protein assimilation. Breath test results were expressed as maximum percentage of administered dose of 13C (%max) and cumulative percentage at the end of the test (%cum(end)). Data were stratified according to renal function. As compared to subjects with glomerular filtration rate (GFR) > or = 60 mL/min/1.73 m2, subjects with GFR < 30 mL/min/1.73 m2 demonstrated significantly lower breath test-derived parameters of protein assimilation (%max 3.97 +/- 0.23 vs. 5.20 +/- 0.23, P=0.0017; %cum(end) 13.91 +/- 0.86 vs. 17.40 +/- 0.80, P= 0.013) and significantly higher urinary output of p-cresol (54.88 mg/24 hours vs. 28.65 mg/24 hours, P= 0.0005). %max (r=0.399, P < 0.0001), %cum(end) (r=0.347, P=0.0007), and urinary p-cresol (r=-0.229, P=0.007) correlated significantly with GFR. Serum albumin correlated significantly with %max (r=0.399, P=0.0002), %cum(end) (r=0.408, P=0.0001), and urinary p-cresol output (r=-0.186, P=0.035). Our data provide evidence that protein assimilation is impaired in CRF. This impairment might contribute to protein malnutrition in CRF.

Improving contingency management programs for addiction

Contingency management interventions effectively reduce or eliminate some individuals' problem substance use. Typically, those who do not benefit never experience the reward or planned contingency available through the intervention because they never produce the behavior (often abstinence) on which the reward is contingent. With two analog studies, we examine whether the effectiveness contingency management interventions improves when contingencies are arranged in ways that improve the likelihood of all participants experiencing the available reward. Participants were smokers not planning to quit. In Study 1, smokers were paid $0, 1, 3, 10, or 30 each day for 5 days for delivery of breath carbon monoxide (CO) levels either ≤4 ppm or below half the median of their baseline levels. Higher payment amounts and the easier target criterion resulted in a higher likelihood of participants meeting criterion. Once participants met the 4 ppm criterion, however, they often maintained this behavior even in the absence of payments for reduced breath CO levels. An ineffective contingency management system was made effective based on these results. Study 2 examined the effectiveness of percentile schedules at reducing breath CO levels. Percentile schedules shaped lower breath CO levels. The effectiveness of percentile schedules in shaping abstinence was tested in treatment seekers, and percentile schedules were found to be effective at shaping abstinence.

Pulmonary involvement in type 1 Gaucher disease: functional and exercise findings in patients with and without clinical interstitial lung disease.

Pulmonary disease is a well-known complication of Type 1 Gaucher disease (GD), although its incidence is not well established and its severity varies. The purpose of this study was to determine the frequency and extent of pulmonary involvement in patients with GD. Pulmonary involvement was assessed by history, physical examination and chest radiograph in 150 consecutive patients with Type 1 GD presenting at a specialized center for genetic diseases. Five patients were noted to have clinical evidence of pulmonary involvement. Full pulmonary function tests were performed in these five patients and in an additional 13 patients randomly selected from the remaining 145. Many of the 18 patients also underwent radionuclide body imaging with 67 Gallium citrate and 111Indium-tagged leucocyte scans, as well as incremental cardiorespiratory exercise tests. Lung biopsies were available in two patients with lung disease, and a second examination of lung tissue was performed in one of these two patients post-mortem. Clinical lung disease was detected in five patients. All five had dyspnea, diffuse infiltrates, restrictive impairment and low single breath CO diffusing capacity (DLCOSB). Two of these patients underwent exercise testing and showed abnormalities consistent with lung disease (ventilatory limitation, excessive ventilation and increased dead space) as well as decreased VO2 max. and anaerobic threshold (AT). In contrast, in the other 13 patients, physical examination, chest radiographs and pulmonary function were normal (except for a low DLCOSB in one patient). Responses on exercise testing (performed in six of the 13 patients) were consistent with a circulatory impairment (decreased VO2 max. and AT). Our study found that <5% of patients with Type 1 GD have clinical interstitial lung disease. In addition, we found that some patients, without evident lung involvement, may experience limitations in physical exertion and are easily fatigued; this is attributable to impaired circulation.

Plasma fatty acids and [13C]linoleic acid metabolism in preterm infants fed a formula with medium-chain triglycerides

Most preterm infant formulas contain medium-chain triacylglycerols (MCT), but the effects of MCT on polyunsaturated fatty acid status and metabolism are controversial. Thus, we studied the effects of MCT on linoleic acid metabolism using stable isotopes. Enterally fed preterm infants were randomized to receive for 7 days 40% of fat as MCT (n = 10) or a formula without MCT (n = 9). At study day 5, infants received orally 2 mg/kg body weight of (13)C-labeled linoleic acid. Fatty acids in plasma lipid classes and (13)C enrichment of phospholipid fatty acids were measured and tracer oxidation was monitored. Compared with the control group, the MCT group showed lower breath (13)CO(2) and higher plasma triacylglycerol contents of octanoic acid, of decanoic acid, and of total long-chain polyunsaturated fatty acids (57.1 +/- 4.4 micro mol/l vs. 37.9 +/- 4.8 micro mol/l, P < 0.01). Concentrations of several polyunsaturated fatty acids in plasma phospholipids and non esterified fatty acids were higher in the MCT group. (13)C concentrations in phospholipid n-6 fatty acids indicated no difference in the relative conversion of linoleic to arachidonic acid. We conclude that oral MCT effectively reduce polyunsaturated fatty acid and long chain polyunsaturated fatty acid oxidation in preterm infants without compromising endogenous n-6 long chain polyunsaturated fatty acid synthesis.

On-line, simultaneous quantification of ethanol, some metabolites and water vapour in breath following the ingestion of alcohol

Selected ion flow tube mass spectrometry, SIFT-MS, has been used to measure simultaneously the concentrations in exhaled breath of ethanol, acetaldehyde, ammonia, acetone and, routinely, water vapour, following the ingestion of various amounts of ethanol in 500 ml of water. These breath analyses were obtained from only single exhalations, the results being available immediately in real time. The breath ethanol reaches concentrations that are only approximately consistent with its dilution in blood and body water. For moderate ethanol doses the decay quickly exhibits first-order kinetics (a single exponential decay) whereas for relatively large ethanol doses, the initial decay of ethanol from the breath is slow, indicating saturation kinetics. For smaller doses, and following a meal, the breath ethanol increases only slightly indicating that it is largely metabolized in the stomach. We suggest that the time delay (following ethanol ingestion) before the breath ethanol begins to increase is an indicator of the gastric emptying rate. Then the rate of decay of ethanol from the breath/blood is related to its rate of metabolism subsequent to its dispersal into the body water. The much lower breath acetaldehyde levels correlate well with the ethanol levels indicating that it is mostly formed from the metabolism of the ethanol. The breath ammonia is seen to ‘dip’ following the water/alcohol drink and this is consistent with previous work in which this same phenomenon was observed following the ingestion of comparable volumes of liquid meals. The simultaneous breath acetone concentrations increase somewhat with time as is expected during the fasting state. The water vapour measurements are indicators of the precision and accuracy of the breath analyses, these being sufficient to show the differences between the breath (body) temperatures of the individuals of less than 1 °C. This study demonstrates the potential of SIFT-MS for non-invasive physiological measurement.

Autonomic and EEG patterns distinguish transcending from other experiences during Transcendental Meditation practice

This study compared EEG and autonomic patterns during transcending to ‘other’ experiences during Transcendental Meditation (TM) practice. To correlate specific meditation experiences with physiological measures, the experimenter rang a bell three times during the TM session. Subjects categorized their experiences around each bell ring. Transcending, in comparison to ‘other’ experiences during TM practice, was marked by: (1) significantly lower breath rates; (2) higher respiratory sinus arrhythmia amplitudes; (3) higher EEG alpha amplitude; and (4) higher alpha coherence. In addition, skin conductance responses to the experimenter-initiated bell rings were larger during transcending. These findings suggest that monitoring patterns of physiological variables may index dynamically changing inner experiences during meditation practice. This could allow a more precise investigation into the nature of meditation experiences and a more accurate comparison of meditation states with other eyes-closed conditions.