Correction of measurement error in a commercial multiple-breath washout device

AbstractRationaleNitrogen multiple-breath washout (N2MBW) is an established technique to assess functional residual capacity (FRC) and ventilation inhomogeneity in the lung. Accurate measurement of gas concentrations is essential for the appropriate calculation of clinical outcomes.ObjectivesWe investigated the accuracy of oxygen and carbon dioxide measurements used for the indirect calculation of nitrogen concentration in a commercial MBW device (Exhalyzer D, Eco Medics AG, Duernten, Switzerland) and its impact on FRC and lung clearance index (LCI).MethodsHigh precision calibration gas mixtures and mass spectrometry were used to evaluate sensor output. We assessed the impact of corrected signal processing on FRC and LCI in a dataset of healthy children and children with cystic fibrosis using custom analysis software.ResultsWe found inadequate correction for the cross sensitivity of the oxygen and carbon dioxide sensors in the Exhalyzer D device. This results in an overestimation of expired nitrogen concentration, and consequently FRC and LCI outcomes. Breath-by-breath correction of this error reduced mean (SD) FRC by 8.9 (2.2)% and LCI by 11.9 (4.0)%. It also resulted in almost complete disappearance of the tissue nitrogen signal at the end of measurements.ConclusionsInadequate correction for cross sensitivity between the oxygen and carbon dioxide gas sensors of the Exhalyzer D device leads to an overestimation of FRC and LCI. Correction of this error is possible and could be applied by re-analysing the measurements breath-by-breath in an updated software version.Grants, Gifts, Equipment, DrugsEco Medics AG (Duernten, Switzerland) provided a research version of their commercial software Spiroware 3.2.1 including insight on signal processing algorithms and helped with the acquisition of mass spectrometry measurements. This project was funded by the Swiss National Science Foundation, Grant Nr. 182719 (P. Latzin) and 168173 (K. Ramsey)

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Correction of sensor crosstalk error in Exhalyzer D multiple-breath washout device significantly impacts outcomes in children with cystic fibrosis

Journal of Applied Physiology ◽

10.1152/japplphysiol.00338.2021 ◽

2021 ◽

Author(s):

Florian Wyler ◽

Marc-Alexander H. Oestreich ◽

Bettina Sarah Frauchiger ◽

Kathryn A. Ramsey ◽

Philipp T. Latzin

Keyword(s):

Carbon Dioxide ◽

Cystic Fibrosis ◽

Functional Residual Capacity ◽

Nitrogen Concentration ◽

Lung Clearance ◽

Cross Sensitivity ◽

Carbon Dioxide Gas ◽

Lung Clearance Index ◽

Multiple Breath Washout ◽

Residual Capacity

Rationale: Nitrogen multiple-breath washout is an established technique to assess functional residual capacity and ventilation inhomogeneity in the lung. Accurate measurement of gas concentrations is essential for the appropriate calculation of clinical outcomes. Objectives: We investigated the accuracy of oxygen and carbon dioxide gas sensor measurements used for the indirect calculation of nitrogen concentration in a commercial multiple-breath washout device (Exhalyzer D, Eco Medics AG, Duernten, Switzerland) and its impact on functional residual capacity and lung clearance index. Methods: High precision calibration gas mixtures and mass spectrometry were used to evaluate sensor output. We assessed the impact of corrected signal processing on multiple-breath washout outcomes in a dataset of healthy children and children with cystic fibrosis using custom analysis software. Results: We found inadequate correction for the cross sensitivity of the oxygen and carbon dioxide sensors in the Exhalyzer D device. This results in an overestimation of expired nitrogen concentration, and consequently multiple-breath washout outcomes. Breath-by-breath correction of this error reduced the mean (SD) cumulative expired volume by 19.6 (5.0)%, functional residual capacity by 8.9 (2.2)%, and lung clearance index by 11.9 (4.0)%. It also substantially reduced the level of the tissue nitrogen signal at the end of measurements. Conclusions: Inadequate correction for cross sensitivity in the oxygen and carbon dioxide gas sensors of the Exhalyzer D device leads to an overestimation of functional residual capacity and lung clearance index. Correction of this error is possible and could be applied by re-analyzing the measurements in an updated software version.

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Do clinimetric properties of LCI change after correction of signal processing?

10.22541/au.164037495.54772910/v1 ◽

2021 ◽

Author(s):

Bettina Frauchiger ◽

Marc-Alexander Oestreich ◽

Florian Wyler ◽

Nathalie Monney ◽

Corin Willers ◽

...

Keyword(s):

Signal Processing ◽

Response To Intervention ◽

Cohort Studies ◽

Healthy Children ◽

Clinical Validity ◽

Clinical Routine ◽

Cross Sensitivity ◽

Multiple Breath Washout ◽

Health And Disease ◽

Over Time

Background: The recently described sensor-crosstalk error in the multiple-breath washout (MBW) device (Exhalyzer D, Eco Medics AG, Duernten, Switzerland) could highly influence clinimetric properties and the current interpretation of MBW results. This study reanalyzes MBW data from clinical routine in the corrected software version Spiroware® 3.3.1 and evaluates the effect on outcomes. Methods: We included nitrogen-MBW data from healthy children and children with CF from previously published trials and ongoing cohort studies. We specifically compared LCI analyzed in Spiroware 3.2.1 and 3.3.1 with regards to i) feasibility, ii) repeatability and iii) validity as outcome parameters in children with CF. Results: (i) All previously collected measurements could be reanalyzed and resulted in unchanged feasibility in Spiroware 3.3.1. (ii) Short- and midterm repeatability of LCI was similar in both software versions. (iii) Clinical validity of LCI remained similar in Spiroware 3.3.1, however, resulted in lower values. Discrimination between health and disease was comparable between both software versions. The increase in LCI over time was less pronounced with 0.16 LCI units/year (95% CI 0.08; 0.24) vs. 0.30 LCI units/year (95% CI 0.21; 0.38) in 3.2.1. Response to intervention in children receiving CFTR-modulator therapy resulted in a comparable improvement in LCI in both Spiroware versions. Conclusion: Our study confirms that clinimetric properties of LCI remain unaffected after correction for the cross-sensitivity error in Spiroware software.

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Climate-forced changes of bio-productivity of Belorussian terrestrial ecosystems

Исследования Земли из космоса ◽

10.31857/s0205-96142019677-88 ◽

2019 ◽

pp. 77-88

Author(s):

S. A. Lysenko

Keyword(s):

Climate Change ◽

Carbon Dioxide ◽

Vegetation Index ◽

Precipitation Amount ◽

Terrestrial Ecosystems ◽

Vegetation Period ◽

Climatic Trend ◽

Vegetation Growth ◽

Current Century ◽

The Impact

The spatial and temporal particularities of Normalized Differential Vegetation Index (NDVI) changes over territory of Belarus in the current century and their relationship with climate change were investigated. The rise of NDVI is observed at approximately 84% of the Belarus area. The statistically significant growth of NDVI has exhibited at nearly 35% of the studied area (t-test at 95% confidence interval), which are mainly forests and undeveloped areas. Croplands vegetation index is largely descending. The main factor of croplands bio-productivity interannual variability is precipitation amount in vegetation period. This factor determines more than 60% of the croplands NDVI dispersion. The long-term changes of NDVI could be explained by combination of two factors: photosynthesis intensifying action of carbon dioxide and vegetation growth suppressing action of air warming with almost unchanged precipitation amount. If the observed climatic trend continues the croplands bio-productivity in many Belarus regions could be decreased at more than 20% in comparison with 2000 year. The impact of climate change on the bio-productivity of undeveloped lands is only slightly noticed on the background of its growth in conditions of rising level of carbon dioxide in the atmosphere.

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Polyphenol Profiling of Chestnut Pericarp, Integument and Curing Water Extracts to Qualify These Food By-Products as a Source of Antioxidants

Molecules ◽

10.3390/molecules26082335 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2335

Author(s):

Gabriella Pinto ◽

Sabrina De Pascale ◽

Maria Aponte ◽

Andrea Scaloni ◽

Francesco Addeo ◽

...

Keyword(s):

Mass Spectrometry ◽

Negative Impact ◽

Tap Water ◽

Time Of Flight ◽

The Other ◽

Curing Process ◽

Flight Mass Spectrometry ◽

Water Curing ◽

The Impact ◽

By Products

Plant polyphenols have beneficial antioxidant effects on human health; practices aimed at preserving their content in foods and/or reusing food by-products are encouraged. The impact of the traditional practice of the water curing procedure of chestnuts, which prevents insect/mould damage during storage, was studied to assess the release of polyphenols from the fruit. Metabolites extracted from pericarp and integument tissues or released in the medium from the water curing process were analyzed by matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and electrospray-quadrupole-time of flight-mass spectrometry (ESI-qTOF-MS). This identified: (i) condensed and hydrolyzable tannins made of (epi)catechin (procyanidins) and acid ellagic units in pericarp tissues; (ii) polyphenols made of gallocatechin and catechin units condensed with gallate (prodelphinidins) in integument counterparts; (iii) metabolites resembling those reported above in the wastewater from the chestnut curing process. Comparative experiments were also performed on aqueous media recovered from fruits treated with processes involving: (i) tap water; (ii) tap water containing an antifungal Lb. pentosus strain; (iii) wastewater from a previous curing treatment. These analyses indicated that the former treatment determines a 6–7-fold higher release of polyphenols in the curing water with respect to the other ones. This event has a negative impact on the luster of treated fruits but qualifies the corresponding wastes as a source of antioxidants. Such a phenomenon does not occur in wastewater from the other curing processes, where the release of polyphenols was reduced, thus preserving the chestnut’s appearance. Polyphenol profiling measurements demonstrated that bacterial presence in water hampered the release of pericarp metabolites. This study provides a rationale to traditional processing practices on fruit appearance and qualifies the corresponding wastes as a source of bioactive compounds for other nutraceutical applications.

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Quantitative Analysis of Pyrazines and Their Perceptual Interactions in Soy Sauce Aroma Type Baijiu

Foods ◽

10.3390/foods10020441 ◽

2021 ◽

Vol 10 (2) ◽

pp. 441

Author(s):

Yan Yan ◽

Shuang Chen ◽

Yao Nie ◽

Yan Xu

Keyword(s):

Mass Spectrometry ◽

Quantitative Analysis ◽

Ultra Performance Liquid Chromatography ◽

Alcohol Solution ◽

Soy Sauce ◽

Tandem Mass ◽

Odor Thresholds ◽

Quantitative Results ◽

Odor Activity Value ◽

The Impact

Pyrazines are important compounds in soy sauce aroma type Baijiu (SSAB). In this work, a total of 16 pyrazines were analyzed using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC–MS/MS) in SSAB. The quantitative results showed that 2,3,5,6-tetramethylpyrazine, 2,6-dimethylpyrazine and 2,3,5-trimethylpyrazine were the three most concentrated pyrazines. The highest odor activity value (OAV) was determined for 2-ethyl-3,5-dimethylpyrazine. Quantitative analysis combined with descriptive sensory analysis revealed that sub-threshold pyrazines (2,3-dimethylpyrazine, 2,3-diethylpyrazine, 2,3-diethyl-5-methylpyrazine and 2-acetyl-3-methylpyrazine) are significantly correlated with the roasted aroma in SSAB. Our study focused on the impact of sub-threshold pyrazines on the perception of roasted aroma in SSAB. The effect of the sub-threshold pyrazines was detected by the addition of various pyrazines in SSAB samples, despite their sub-threshold concentrations. Furthermore, the presence of sub-threshold pyrazines in dilute alcohol solution resulted in a significant reduction in the odor thresholds of supra-threshold pyrazines. Sensory investigation indicated that pyrazines have a synergistic effect on the perception of roasted aroma. The results highlighted the contribution of some pyrazines to the roasted aroma in SSAB despite their sub-threshold concentrations.

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Matrix-assisted laser desorption ionisation (MALDI) mass spectrometry (MS): basics and clinical applications

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2019-0868 ◽

2020 ◽

Vol 58 (6) ◽

pp. 883-896 ◽

Cited By ~ 3

Author(s):

Muhammad Zubair Israr ◽

Dennis Bernieh ◽

Andrea Salzano ◽

Shabana Cassambai ◽

Yoshiyuki Yazaki ◽

...

Keyword(s):

Mass Spectrometry ◽

Laser Desorption ◽

Maldi Mass Spectrometry ◽

Clinical Applications ◽

Clinical Diagnostics ◽

Maldi Ms ◽

Therapeutic Drug ◽

The Impact ◽

Matrix Assisted Laser ◽

Matrix Assisted Laser Desorption

AbstractBackgroundMatrix-assisted laser desorption ionisation (MALDI) mass spectrometry (MS) has been used for more than 30 years. Compared with other analytical techniques, it offers ease of use, high throughput, robustness, cost-effectiveness, rapid analysis and sensitivity. As advantages, current clinical techniques (e.g. immunoassays) are unable to directly measure the biomarker; rather, they measure secondary signals. MALDI-MS has been extensively researched for clinical applications, and it is set for a breakthrough as a routine tool for clinical diagnostics.ContentThis review reports on the principles of MALDI-MS and discusses current clinical applications and the future clinical prospects for MALDI-MS. Furthermore, the review assesses the limitations currently experienced in clinical assays, the advantages and the impact of MALDI-MS to transform clinical laboratories.SummaryMALDI-MS is widely used in clinical microbiology for the screening of microbial isolates; however, there is scope to apply MALDI-MS in the diagnosis, prognosis, therapeutic drug monitoring and biopsy imaging in many diseases.OutlookThere is considerable potential for MALDI-MS in clinic as a tool for screening, profiling and imaging because of its high sensitivity and specificity over alternative techniques.

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Determination of multi pesticide residues in leaf and needle samples using a modified QuEChERS approach and gas chromatography-tandem mass spectrometry

Analytical Methods ◽

10.1039/d0ay02329a ◽

2021 ◽

Author(s):

Arnelle Löbbert ◽

Sonja Schanzer ◽

Henrik Krehenwinkel ◽

Franz Bracher ◽

Christoph Müller

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Tandem Mass Spectrometry ◽

Forest Ecosystems ◽

Tandem Mass ◽

Modified Quechers ◽

Chromatography Tandem Mass Spectrometry ◽

The Impact ◽

Impact Of Pesticides

A novel, validated QuEChERS-based GC-MS/MS method was developed, which will allow the assessment of the impact of pesticides on forest ecosystems.

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An Examination of Green Credit Promoting Carbon Dioxide Emissions Reduction: A Provincial Panel Analysis of China

Sustainability ◽

10.3390/su13137148 ◽

2021 ◽

Vol 13 (13) ◽

pp. 7148

Author(s):

Wenjie Zhang ◽

Mingyong Hong ◽

Juan Li ◽

Fuhong Li

Keyword(s):

Carbon Dioxide ◽

Carbon Emissions ◽

Carbon Dioxide Emissions ◽

Industrial Structure ◽

Emissions Reduction ◽

Green Finance ◽

Carbon Emissions Reduction ◽

Negative Effect ◽

Emissions Intensity ◽

The Impact

The implementation of green finance is a powerful measure to promote global carbon emissions reduction that has been highly valued by academic circles in recent years. However, the role of green credit in carbon emissions reduction in China is still lacking testing. Using a set of panel data including 30 provinces and cities, this study focused on the impact of green credit on carbon dioxide emissions in China from 2006 to 2016. The empirical results indicated that green credit has a significantly negative effect on carbon dioxide emissions intensity. Furthermore, after the mechanism examination, we found that the promotion impacts of green credit on industrial structure upgrading and technological innovation are two effective channels to help reduce carbon dioxide emissions. Heterogeneity analysis found that there are regional differences in the effect of green credit. In the western and northeastern regions, the effect of green credit is invalid. Quantile regression results implied that the greater the carbon emissions intensity, the better the effect of green credit. Finally, a further discussion revealed there exists a nonlinear correlation between green credit and carbon dioxide emissions intensity. These findings suggest that the core measures to promote carbon emission reduction in China are to continue to expand the scale of green credit, increase the technology R&D investment of enterprises, and to vigorously develop the tertiary industry.

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Effects of Sport-Based Interventions on Children’s Executive Function: A Systematic Review and Meta-Analysis

Brain Sciences ◽

10.3390/brainsci11060755 ◽

2021 ◽

Vol 11 (6) ◽

pp. 755

Author(s):

Falonn Contreras-Osorio ◽

Christian Campos-Jara ◽

Cristian Martínez-Salazar ◽

Luis Chirosa-Ríos ◽

Darío Martínez-García

Keyword(s):

Systematic Review ◽

Working Memory ◽

Executive Function ◽

Inhibitory Control ◽

Cognitive Flexibility ◽

Meta Analysis ◽

Scientific Evidence ◽

Healthy Children ◽

Meta Analyses ◽

The Impact

One of the most studied aspects of children’s cognitive development is that of the development of the executive function, and research has shown that physical activity has been demonstrated as a key factor in its enhancement. This meta-analysis aims to assess the impact of specific sports interventions on the executive function of children and teenagers. A systematic review was carried out on 1 November 2020 to search for published scientific evidence that analysed different sports programs that possibly affected executive function in students. Longitudinal studies, which assessed the effects of sports interventions on subjects between 6 and 18 years old, were identified through a systematic search of the four principal electronic databases: Web of Science, PubMed, Scopus, and EBSCO. A total of eight studies, with 424 subjects overall, met the inclusion criteria and were classified based on one or more of the following categories: working memory, inhibitory control, and cognitive flexibility. The random-effects model for meta-analyses was performed with RevMan version 5.3 to facilitate the analysis of the studies. Large effect sizes were found in all categories: working memory (ES −1.25; 95% CI −1.70; −0.79; p < 0.0001); inhibitory control (ES −1.30; 95% CI −1.98; −0.63; p < 0.00001); and cognitive flexibility (ES −1.52; 95% CI −2.20; −0.83; p < 0.00001). Our analysis concluded that healthy children and teenagers should be encouraged to practice sports in order to improve their executive function at every stage of their development.

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Mycosporine-Like Amino Acids from Red Macroalgae: UV-Photoprotectors with Potential Cosmeceutical Applications

Applied Sciences ◽

10.3390/app11115112 ◽

2021 ◽

Vol 11 (11) ◽

pp. 5112

Author(s):

Julia Vega ◽

Geniane Schneider ◽

Bruna R. Moreira ◽

Carolina Herrera ◽

José Bonomi-Barufi ◽

...

Keyword(s):

Mass Spectrometry ◽

Amino Acids ◽

High Performance ◽

Nitrogen Availability ◽

Antioxidant Properties ◽

Published Data ◽

Diverse Group ◽

Red Macroalgae ◽

Thermo Stability ◽

The Impact

Macroalgae belong to a diverse group of organisms that could be exploited for biomolecule application. Among the biocompounds found in this group, mycosporine-like amino acids (MAAs) are highlighted mainly due to their photoprotection, antioxidant properties, and high photo and thermo-stability, which are attractive characteristics for the development of cosmeceutical products. Therefore, here we revise published data about MAAs, including their biosynthesis, biomass production, extraction, characterization, identification, purification, and bioactivities. MAAs can be found in many algae species, but the highest concentrations are found in red macroalgae, mainly in the order Bangiales, as Porphyra spp. In addition to the species, the content of MAAs can vary depending on environmental factors, of which solar radiation and nitrogen availability are the most influential. MAAs can confer photoprotection due to their capacity to absorb ultraviolet radiation or reduce the impact of free radicals on cells, among other properties. To extract these compounds, different approaches can be used. The efficiency of these methods can be evaluated with characterization and identification using high performance liquid chromatography (HPLC), associated with other apparatus such as mass spectrometry (MS) and nuclear magnetic resonance (NMR). Therefore, the data presented in this review allow a broad comprehension of MAAs and show perspectives for their inclusion in cosmeceutical products.

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