Exhaled breath profiling for diagnosing acute respiratory distress syndrome

The acute respiratory distress syndrome (ARDS) is a common, devastating complication of critical illness that is characterized by pulmonary injury and inflammation. The clinical diagnosis may be improved by means of objective biological markers. Electronic nose (eNose) technology can rapidly and non-invasively provide breath prints, which are profiles of volatile metabolites in the exhaled breath. We hypothesized that breath prints could facilitate accurate diagnosis of ARDS in intubated and ventilated intensive care unit (ICU) patients. Prospective single-center cohort study with training and temporal external validation cohort. Breath of newly intubated and mechanically ventilated ICU-patients was analyzed using an electronic nose within 24 hours after admission. ARDS was diagnosed and classified by the Berlin clinical consensus definition. The eNose was trained to recognize ARDS in a training cohort and the diagnostic performance was evaluated in a temporal external validation cohort. In the training cohort (40 patients with ARDS versus 66 controls) the diagnostic model for ARDS showed a moderate discrimination, with an area under the receiver-operator characteristic curve (AUC-ROC) of 0.72 (95%-confidence interval (CI): 0.63-0.82). In the external validation cohort (18 patients with ARDS versus 26 controls) the AUC-ROC was 0.71 [95%-CI: 0.54 - 0.87]. Restricting discrimination to patients with moderate or severe ARDS versus controls resulted in an AUC-ROC of 0.80 [95%-CI: 0.70 - 0.90]. The exhaled breath profile from patients with cardiopulmonary edema and pneumonia was different from that of patients with moderate/severe ARDS. An electronic nose can rapidly and non-invasively discriminate between patients with and without ARDS with modest accuracy. Diagnostic accuracy increased when only moderate and severe ARDS patients were considered. This implicates that breath analysis may allow for rapid, bedside detection of ARDS, especially if our findings are reproduced using continuous exhaled breath profiling. NTR2750, registered 11 February 201

In vivo imaging of the airway wall in asthma: fibered confocal fluorescence microscopy in relation to histology and lung function

<p>Abstract</p> <p>Background</p> <p>Airway remodelling is a feature of asthma including fragmentation of elastic fibres observed in the superficial elastin network of the airway wall. Fibered confocal fluorescence microscopy (FCFM) is a new and non-invasive imaging technique performed during bronchoscopy that may visualize elastic fibres, as shown by <it>in vitro </it>spectral analysis of elastin powder. We hypothesized that FCFM images capture <it>in vivo </it>elastic fibre patterns within the airway wall and that such patterns correspond with airway histology. We aimed to establish the concordance between the bronchial elastic fibre pattern in histology and FCFM. Second, we examined whether elastic fibre patterns in histology and FCFM were different between asthmatic subjects and healthy controls. Finally, the association between these patterns and lung function parameters was investigated.</p> <p>Methods</p> <p>In a cross-sectional study comprising 16 subjects (8 atopic asthmatic patients with controlled disease and 8 healthy controls) spirometry and bronchoscopy were performed, with recording of FCFM images followed by endobronchial biopsy at the airway main carina. Elastic fibre patterns in histological sections and FCFM images were scored semi-quantitatively. Agreement between histology and FCFM was analysed using linearly weighted kappa κ_w.</p> <p>Results</p> <p>The patterns observed in histological sections and FCFM images could be divided into 3 distinct groups. There was good agreement between elastic fibre patterns in histology and FCFM patterns (κ_w0.744). The semi-quantitative pattern scores were not different between asthmatic patients and controls. Notably, there was a significant difference in post-bronchodilator FEV₁%predicted between the different patterns by histology (p = 0.001) and FCFM (p = 0.048), regardless of asthma or atopy.</p> <p>Conclusion</p> <p>FCFM captures the elastic fibre pattern within the airway wall in humans <it>in vivo</it>. The association between post-bronchodilator FEV₁%predicted and both histological and FCFM elastic fibre patterns points towards a structure-function relationship between extracellular matrix in the airway wall and lung function.</p> <p>Trial registration</p> <p>Netherlands Trial Register <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=NTR1306">NTR1306</a></p

Breath analysis by gas chromatography-mass spectrometry and electronic nose to screen for pleural mesothelioma : a cross-sectional case-control study

Rationale: Malignant pleural mesothelioma (MPM) is mainly caused by previous exposure to asbestos fibers and has a poor prognosis. Due to a long latency period between exposure and diagnosis, MPM incidence is expected to peak between 2020-2025. Screening of asbestos-exposed individuals is believed to improve early detection and hence, MPM management. Recent developments focus on breath analysis for screening since breath contains volatile organic compounds (VOCs) which reflect the cell’s metabolism. Objectives: The goal of this cross-sectional, case-control study is to identify VOCs in exhaled breath of MPM patients with gas chromatography-mass spectrometry (GC-MS) and to assess breath analysis to screen for MPM using an electronic nose (eNose). Methods: Breath and background samples were taken from 64 subjects: 16 healthy controls (HC), 19 asymptomatic former asbestos-exposed (AEx) individuals, 15 patients with benign asbestos-related diseases (ARD) and 14 MPM patients. Samples were analyzed with both GC-MS and eNose. Results: Using GC-MS, AEx individuals were discriminated from MPM patients with 97% accuracy, with diethyl ether, limonene, nonanal, methylcyclopentane and cyclohexane as important VOCs. This was validated by eNose analysis. MPM patients were discriminated from AEx+ARD participants by GC-MS and eNose with 94% and 74% accuracy, respectively. The sensitivity, specificity, positive and negative predictive values were 100%, 91%, 82%, 100% for GC-MS and 82%, 55%, 82%, 55% for eNose, respectively. Conclusion: This study shows accurate discrimination of patients with MPM from asymptomatic asbestos-exposed persons at risk by GC-MS and eNose analysis of exhaled VOCs and provides proof-of-principle of breath analysis for MPM screening

Asthma control cost-utility randomized trial evaluation (ACCURATE): the goals of asthma treatment

Contains fulltext : 97659.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: Despite the availability of effective therapies, asthma remains a source of significant morbidity and use of health care resources. The central research question of the ACCURATE trial is whether maximal doses of (combination) therapy should be used for long periods in an attempt to achieve complete control of all features of asthma. An additional question is whether patients and society value the potential incremental benefit, if any, sufficiently to concur with such a treatment approach. We assessed patient preferences and cost-effectiveness of three treatment strategies aimed at achieving different levels of clinical control: 1. sufficiently controlled asthma 2. strictly controlled asthma 3. strictly controlled asthma based on exhaled nitric oxide as an additional disease marker DESIGN: 720 Patients with mild to moderate persistent asthma from general practices with a practice nurse, age 18-50 yr, daily treatment with inhaled corticosteroids (more then 3 months usage of inhaled corticosteroids in the previous year), will be identified via patient registries of general practices in the Leiden, Nijmegen, and Amsterdam areas in The Netherlands. The design is a 12-month cluster-randomised parallel trial with 40 general practices in each of the three arms. The patients will visit the general practice at baseline, 3, 6, 9, and 12 months. At each planned and unplanned visit to the general practice treatment will be adjusted with support of an internet-based asthma monitoring system supervised by a central coordinating specialist nurse. Patient preferences and utilities will be assessed by questionnaire and interview. Data on asthma control, treatment step, adherence to treatment, utilities and costs will be obtained every 3 months and at each unplanned visit. Differences in societal costs (medication, other (health) care and productivity) will be compared to differences in the number of limited activity days and in quality adjusted life years (Dutch EQ5D, SF6D, e-TTO, VAS). This is the first study to assess patient preferences and cost-effectiveness of asthma treatment strategies driven by different target levels of asthma control. Trial registration: Netherlands Trial Registration NTR1756

Publication Bias in Laboratory Animal Research: A Survey on Magnitude, Drivers, Consequences and Potential Solutions

Contains fulltext : 109229.pdf (publisher's version ) (Open Access)CONTEXT: Publication bias jeopardizes evidence-based medicine, mainly through biased literature syntheses. Publication bias may also affect laboratory animal research, but evidence is scarce. OBJECTIVES: To assess the opinion of laboratory animal researchers on the magnitude, drivers, consequences and potential solutions for publication bias. And to explore the impact of size of the animals used, seniority of the respondent, working in a for-profit organization and type of research (fundamental, pre-clinical, or both) on those opinions. DESIGN: Internet-based survey. SETTING: All animal laboratories in The Netherlands. PARTICIPANTS: Laboratory animal researchers. MAIN OUTCOME MEASURE(S): Median (interquartile ranges) strengths of beliefs on 5 and 10-point scales (1: totally unimportant to 5 or 10: extremely important). RESULTS: Overall, 454 researchers participated. They considered publication bias a problem in animal research (7 (5 to 8)) and thought that about 50% (32-70) of animal experiments are published. Employees (n = 21) of for-profit organizations estimated that 10% (5 to 50) are published. Lack of statistical significance (4 (4 to 5)), technical problems (4 (3 to 4)), supervisors (4 (3 to 5)) and peer reviewers (4 (3 to 5)) were considered important reasons for non-publication (all on 5-point scales). Respondents thought that mandatory publication of study protocols and results, or the reasons why no results were obtained, may increase scientific progress but expected increased bureaucracy. These opinions did not depend on size of the animal used, seniority of the respondent or type of research. CONCLUSIONS: Non-publication of "negative" results appears to be prevalent in laboratory animal research. If statistical significance is indeed a main driver of publication, the collective literature on animal experimentation will be biased. This will impede the performance of valid literature syntheses. Effective, yet efficient systems should be explored to counteract selective reporting of laboratory animal research

Refractory&quot; eosinophilic airway inflammation in severe asthma: effect of parenteral corticosteroids

It has been suggested that patients with refractory eosinophilic airway inflammation represent a separate &quot;eosinophilic&quot; asthma phenotype associated with increased morbidity and a poor prognosis. To investigate whether persistent eosinophilia in these patients is a fixed feature or can still be modified by treatment, we investigated the effect of high-dose intramuscular corticosteroids on eosinophils in induced sputum. Twenty-two patients with stable severe asthma (15 women, aged 21-73 years) participated in this double-blind, placebo-controlled study. All were using inhaled corticosteroids (у 1,600 g/day) or chronic oral prednisone. They were included if the percentage of eosinophils in induced sputum was above the upper limit of normal (у 2%). Two weeks after treatment with triamcinolone, but not placebo, sputum eosinophils almost completely disappeared from a median of 12.6-0.2% (p Ͻ 0.001). In 82% of patients, no eosinophils could be observed at all. In addition, the rescue medication score decreased from 1.4 to 0.8 (p ϭ 0.01), and FEV 1 improved from a median of 73.8-88.3% predicted (p ϭ 0.001). We conclude that persistent sputum eosinophilia despite extensive antiasthma treatment is not a refractory phenomenon but is still sensitive to high-dose systemic corticosteroids. This implies that these patients with severe asthma need additional or alternative antiinflammatory treatment to combat the eosinophilia and associated poor prognosis. Keywords: asthma; eosinophilia; glucocorticoids; phenotype; sputum; severity of illness index There is now accumulating evidence that patients with bronchial asthma are heterogeneous with respect to the type of inflammation in the airways and the response to antiinflammatory therapy (1-4). Most patients with asthma have eosinophilic airway inflammation with good response to treatment with inhaled corticosteroids (5). However, a relatively large proportion of adult asthma cases is characterized by neutrophilic airway inflammation (4, 6), in particular those with severe disease (7-9). These patients are more difficult to treat and often require high doses of inhaled or oral corticosteroids to control their disease. Remarkably, bronchial biopsy and bronchoalveolar lavage studies have shown that in a subgroup of patients with severe asthma such neutrophilic airway inflammation is accompanied by persistent eosinophilic inflammation (10, 11). Eosinophilic inflammation in the airway mucosa that persists despite the use of high doses of inhaled corticosteroids or oral corticosteroids has been observed in several studies Correspondence and requests for reprints should be addressed to Elisabeth H. and has been implicated by Wenzel and colleagues as a feature of a separate asthma phenotype, associated with poor asthma prognosis (10, 12). Indeed, studies have shown that eosinophilic inflammation despite vigorous antiasthma treatment is associated with remodeling of the airways, impaired lung function, and near-fatal asthma attacks Why eosinophilia is persisting in these patients is unknown. Moreover, it has not been investigated whether persistent eosinophilia is a permanent characteristic of a specific phenotype of severe asthma or can be modulated by more intensive treatment. In this study, we investigated the effect of high-dose intramuscular corticosteroids on sputum eosinophilia in a subgroup of patients with severe asthma featuring persistent eosinophilia despite extensive antiinflammatory treatment. In addition, the effect of intramuscular corticosteroids on asthma symptoms, lung function, peripheral blood eosinophils, and nitric oxide in exhaled breath was examined. The results of this study have been published previously in the form of an abstract (21). METHODS Patients The patients in this study were part of a cohort of severe asthma patients participating in studies aimed at identifying risk factors of asthma severity Design The study had a randomized, parallel, double-blind, placebo-controlled design. At baseline (Visit 1), patients&apos; characteristics were documented, and Borg score, postbronchodilator FEV 1 , and level of exhaled nitric oxide were assessed. A blood sample was taken, and sputum was induced. If the sputum eosinophil percentage exceeded 2%, patients were randomized to one of the two treatments, with stratification for daily use of oral steroids (strata yes/no), and level of sputum eosinophil percentage (strata 2-10% or Ͼ 10%). After 1 week (Visit 2), one single intramuscular injection of 3 ml (40 mg/ml) long-acting triamcinolone acetonide (Kenacort-A40; Bristol-Myers Squibb, Woerden, The Netherlands) or matched placebo (3 ml NaCl 0.9%) was given. Intramuscular administration was chosen instead of a course of oral corticosteroids to avoid any confounding by noncompliance with therapy. Two weeks thereafter (Visit 3), the measurements performed at Visit 1 were repeated. A diary was completed by the patients during the first and third weeks of the study. Measurements Postbronchodilator FEV 1 was assessed (24) 30 minutes after the inhalation of 400 g salbutamol, and exhaled nitric oxide measurements wer

Compartmentalized Synthesis of Triacylglycerol at the Inner Nuclear Membrane Regulates Nuclear Organization.

Cells dynamically adjust organelle organization in response to growth and environmental cues. This requires regulation of synthesis of phospholipids, the building blocks of organelle membranes, or remodeling of their fatty-acyl (FA) composition. FAs are also the main components of triacyglycerols (TGs), which enable energy storage in lipid droplets. How cells coordinate FA metabolism with organelle biogenesis during cell growth remains unclear. Here, we show that Lro1, an acyltransferase that generates TGs from phospholipid-derived FAs in yeast, relocates from the endoplasmic reticulum to a subdomain of the inner nuclear membrane. Lro1 nuclear targeting is regulated by cell cycle and nutrient starvation signals and is inhibited when the nucleus expands. Lro1 is active at this nuclear subdomain, and its compartmentalization is critical for nuclear integrity. These data suggest that Lro1 nuclear targeting provides a site of TG synthesis, which is coupled with nuclear membrane remodeling

Compartmentalized Synthesis of Triacylglycerol at the Inner Nuclear Membrane Regulates Nuclear Organization

Cells dynamically adjust organelle organization in response to growth and environmental cues. This requires regulation of synthesis of phospholipids, the building blocks of organelle membranes, or remodeling of their fatty-acyl (FA) composition. FAs are also the main components of triacyglycerols (TGs), which enable energy storage in lipid droplets. How cells coordinate FA metabolism with organelle biogenesis during cell growth remains unclear. Here, we show that Lro1, an acyltransferase that generates TGs from phospholipid-derived FAs in yeast, relocates from the endoplasmic reticulum to a subdomain of the inner nuclear membrane. Lro1 nuclear targeting is regulated by cell cycle and nutrient starvation signals and is inhibited when the nucleus expands. Lro1 is active at this nuclear subdomain, and its compartmentalization is critical for nuclear integrity. These data suggest that Lro1 nuclear targeting provides a site of TG synthesis, which is coupled with nuclear membrane remodeling

Metabolic differences between bronchial epithelium from healthy individuals and patients with asthma and the effect of bronchial thermoplasty

Background: Asthma is a heterogeneous disease with differences in onset, severity, and inflammation. Bronchial epithelial cells (BECs) contribute to asthma pathophysiology. Objective: We determined whether transcriptomes of BECs reflect heterogeneity in inflammation and severity in asthma, and whether this was affected in BECs from patients with severe asthma after their regeneration by bronchial thermoplasty. Methods: RNA sequencing was performed on BECs obtained by bronchoscopy from healthy controls (n = 16), patients with mild asthma (n = 17), patients with moderate asthma (n = 5), and patients with severe asthma (n = 17), as well as on BECs from treated and untreated airways of the latter (also 6 months after bronchial thermoplasty) (n = 23). Lipidome and metabolome analyses were performed on cultured BECs from healthy controls (n = 7); patients with severe asthma (n = 9); and, for comparison, patients with chronic obstructive pulmonary disease (n = 7). Results: Transcriptome analysis of BECs from patients showed a reduced expression of oxidative phosphorylation (OXPHOS) genes, most profoundly in patients with severe asthma but less profoundly and more heterogeneously in patients with mild asthma. Genes related to fatty acid metabolism were significantly upregulated in asthma. Lipidomics revealed enhanced levels of lipid species (phosphatidylcholines, lysophosphatidylcholines. and bis(monoacylglycerol)phosphate), whereas levels of OXPHOS metabolites were reduced in BECs from patients with severe asthma. BECs from patients with mild asthma characterized by hyperresponsive production of mediators implicated in neutrophilic inflammation had decreased expression of OXPHOS genes compared with that in BECs from patients with mild asthma with normoresponsive production. BECs obtained after thermoplasty had significantly increased expression of OXPHOS genes and decreased expression of fatty acid metabolism genes compared with BECs obtained from untreated airways. Conclusion: BECs in patients with asthma are metabolically different from those in healthy individuals. These differences are linked with inflammation and asthma severity, and they can be reversed by bronchial thermoplasty

Multiscale Variability and the Comparison of Ground and Satellite Radar Based Measures of Peatland Surface Motion for Peatland Monitoring

Peatland surface motion is highly diagnostic of peatland condition. Interferometric Synthetic Aperture Radar (InSAR) can measure this at the landscape scale but requires ground validation. This necessitates upscaling from point to areal measures (80 × 90 m) but is hampered by a lack of data regarding the spatial variability of peat surface motion characteristics. Using a nested precise leveling approach within two areas of upland and low-lying blanket peatland within the Flow Country, Scotland, we examine the multiscale variability of peat surface motion. We then compare this with InSAR timeseries data. We find that peat surface motion varies at multiple scales within blanket peatland with decreasing dynamism with height above the water table e.g., hummocks < lawn < hollows. This trend is dependent upon a number of factors including ecohydrology, pool size/density, peat density, and slope. At the site scale motion can be grouped into central, marginal, and upland peatlands with each showing characteristic amplitude, peak timing, and response to climate events. Ground measurements which incorporate local variability show good comparability with satellite radar derived timeseries. However, current limitations of phase unwrapping in interferometry means that during an extreme drought/event InSAR readings can only qualitatively replicate peat movement in the most dynamic parts of the peatland e.g., pool systems, quaking bog