Publications by authors named "Federico Gómez"

65 Publications

Heat knockdown resistance and chill-coma recovery as correlated responses to selection on mating success at high temperature in .

Ecol Evol 2020 Feb 6;10(4):1998-2006. Epub 2020 Feb 6.

Departamento de Ecología Genética y Evolución Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Buenos Aires Argentina.

Reproduction and related traits such as mating success are strongly affected by thermal stress. We tested direct and correlated responses to artificial selection in replicated lines of that were selected for mating success at high temperature. Knockdown resistance at high temperature (KRHT) and chill-coma recovery (CCR) were tested as correlated selection responses. Virgin flies were allowed to mate for four hours at 33°C in three replicated lines (S lines) to obtain the selected flies and then returned at 25°C to lay eggs. Other three replicated lines were maintained at 25°C without any selection as control (C lines). After 15 selection generations, KRHT and CCR were measured. Both traits were assessed in flies that did not receive any hardening pretreatments as well as in flies that were either heat or cold hardened. Thermotolerance traits showed significant correlated responses with higher KRHT in S than in C lines, both with a heat-hardening pretreatment and without a heat-hardening pretreatment. CCR time was longer in S than in C lines both with a cold-hardening pretreatment and without a cold-hardening pretreatment. Hardening treatments improved both KRHT and CCR in all cases excepting KRHT in C lines. Overall, KRHT and CCR showed an antagonistic pattern of correlated responses to our selection regime, suggesting either pleiotropy or tightly linked trait-specific genes partially affecting KRHT and CCR.
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http://dx.doi.org/10.1002/ece3.6032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7042739PMC
February 2020

Negative genetic correlation between longevity and its hormetic extension by dietary restriction in Drosophila melanogaster.

Biogerontology 2020 04 30;21(2):191-201. Epub 2019 Nov 30.

Facultad de Ciencias Exactas y Naturales, Departamento de Ecología, Genética y Evolución, Universidad de Buenos Aires, C-1428-EHA, Buenos Aires, Argentina.

Longevity is a highly malleable trait which is influenced by many genetic and environmental factors including nutrition. Mild stress of dietary restriction (DR) is often beneficial by extending longevity in many organisms. Here, DR-induced effects on longevity were tested for genetic variation in a set of recombinant inbred lines (RIL) in D. melanogaster. Genetic variability was significant in the longevity response following a DR-treatment across RIL, with detrimental effects in several RIL but beneficial effects in other RIL. One quantitative trait locus (QTL) was consistently significant in the middle of chromosome 2 for DR-induced changes in longevity, including hormesis (an increase in longevity by DR). Another QTL co-localized with a previously found QTL for starvation resistance in females. Several other QTL were also significant on most chromosomal arms. Longevity in controls was negatively correlated to DR effects across RIL for longevity in females, the sex showing higher DR-induced hormesis. This negative genetic correlation highlights the importance to further investigate the effects of genetic variation in the strength of DR-induced hormesis in longevity and its sex-specificity.
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http://dx.doi.org/10.1007/s10522-019-09852-zDOI Listing
April 2020

Microchip Electrophoresis Tools for the Analysis of Small Molecules.

Methods Mol Biol 2019 ;1906:197-206

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina.

Microchip electrophoresis (ME) results from miniaturization of capillary electrophoresis (CE) to a microfabricated separation device. Both techniques have common characteristics, but in some aspects, the microfluidic separation device has unique features resulting from its planar miniaturized format. Here we describe the process to transfer of CE to ME and the benefits and drawbacks of the chip with respect to the capillary. A practical guide for method development on the microchip for small ionizable molecules such as phenolic compounds, amino acids, or alkaloids is also presented.
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http://dx.doi.org/10.1007/978-1-4939-8964-5_13DOI Listing
June 2019

Natural deep eutectic solvents-mediated extractions: The way forward for sustainable analytical developments.

Anal Chim Acta 2018 Dec 26;1038:1-10. Epub 2018 Jul 26.

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina. Electronic address:

The concept of sustainable development has impacted in analytical chemistry changing the way of thinking processes and methods. It is important for analytical chemists to consider how sample preparation can integrate the basic concepts of Green Chemistry. In this sense, the replacement of traditional organic solvents is of utmost importance. Natural Deep Eutectic Solvents (NADES) have come to light as a green alternative. In the last few years, a growing number of contributions have applied these natural solvents proving their efficiency in terms of extraction ability, analyte stabilization capacity and detection compatibility. However, the arising question that has to be answered is: the use of NADES is enough to green an extraction process? This review presents an overview of knowledge regarding sustainability of NADES-based extraction procedures, focused on reported literature within the timeframe spanning from 2011 up to date. The contributions were analyzed from a green perspective in terms of energy, time, sample and solvent consumption. Moreover, we include a critical analysis to clarify whether the use of NADES as extraction media is enough for greening an analytical methodology; strategies to make them even greener are also presented. Finally, recent trends and future perspectives on how NADES-based extraction approaches in combination with computational methodologies can contribute are discussed.
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http://dx.doi.org/10.1016/j.aca.2018.07.059DOI Listing
December 2018

Determination of ellagic acid by capillary electrophoresis in Argentinian wines.

Electrophoresis 2018 07 24;39(13):1621-1627. Epub 2018 Apr 24.

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina.

Rising interest in ellagic acid (EA) present in functional foods is supported by its antimutagenic, anticarcinogenic, antiviral, antibacterial and antioxidative effects. The present approach presents for the first time the determination of ellagic acid and other phenolics in wines by miniaturized solid phase extraction prior to capillary zone electrophoresis (CZE) with UV. The extraction was performed using a home-made miniaturized pipette tip column. The procedure allowed a significant reduction in conditioning/sample/washing/elution volumes. The effects of important factors affecting the extraction efficiency as well as electrophoretic performance were investigated to acquire optimum conditions. The analytes were separated within 10 min with a BGE containing 30 mmol/L sodium tetraborate 10% v/v MeOH pH 9.10. The optimized method was applied to the determination of ellagic acid in commercial and pilot-scale wines. Indeed, the content of EA was correlated with viticultural parameters such as grape varietal, production area, and aging conditions (oak wood guard and glass bottle ward). In order to validate the results, a comparison between the CZE and HPLC data was made.
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http://dx.doi.org/10.1002/elps.201700487DOI Listing
July 2018

Instrumental drift removal in GC-MS data for breath analysis: the short-term and long-term temporal validation of putative biomarkers for COPD.

J Breath Res 2018 03 14;12(3):036007. Epub 2018 Mar 14.

Signal and Information Processing for Sensing Systems, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain.

Breath analysis holds the promise of a non-invasive technique for the diagnosis of diverse respiratory conditions including chronic obstructive pulmonary disease (COPD) and lung cancer. Breath contains small metabolites that may be putative biomarkers of these conditions. However, the discovery of reliable biomarkers is a considerable challenge in the presence of both clinical and instrumental confounding factors. Among the latter, instrumental time drifts are highly relevant, as since question the short and long-term validity of predictive models. In this work we present a methodology to counter instrumental drifts using information from interleaved blanks for a case study of GC-MS data from breath samples. The proposed method includes feature filtering, and additive, multiplicative and multivariate drift corrections, the latter being based on component correction. Biomarker discovery was based on genetic algorithms in a filter configuration using Fisher's ratio computed in the partial least squares-discriminant analysis subspace as a figure of merit. Using our protocol, we have been able to find nine peaks that provide a statistically significant area under the ROC curve of 0.75 for COPD discrimination. The method developed has been successfully validated using blind samples in short-term temporal validation. However, the attempt to use this model for patient screening six months later was not successful. This negative result highlights the importance of increasing validation rigor when reporting biomarker discovery results.
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http://dx.doi.org/10.1088/1752-7163/aaa492DOI Listing
March 2018

A novel Burkholderia ambifaria strain able to degrade the mycotoxin fusaric acid and to inhibit Fusarium spp. growth.

Microbiol Res 2018 Jan 22;206:50-59. Epub 2017 Sep 22.

Instituto de Investigaciones en Biociencias Agrícolas y Ambientales, Universidad de Buenos Aires, CONICET, FAUBA. Av. San Martín 4453, C1417DSE, Ciudad Autónoma de Buenos Aires, Argentina. Electronic address:

Fusaric acid (FA) is a fungal metabolite produced by several Fusarium species responsible for wilts and root rot diseases of a great variety of plants. Bacillus spp. and Pseudomonas spp. have been considered as promising biocontrol agents against phytopathogenic Fusarium spp., however it has been demonstrated that FA negatively affects growth and production of some antibiotics in these bacteria. Thus, the capability to degrade FA would be a desirable characteristic in bacterial biocontrol agents of Fusarium wilt. Taking this into account, bacteria isolated from the rhizosphere of barley were screened for their ability to use FA as sole carbon and energy source. One strain that fulfilled this requirement was identified according to sequence analysis of 16S rRNA, gyrB and recA genes as Burkholderia ambifaria. This strain, designated T16, was able to grow with FA as sole carbon, nitrogen and energy source and also showed the ability to detoxify FA in barley seedlings. This bacterium also exhibited higher growth rate, higher cell densities, longer survival, higher levels of indole-3-acetic acid (IAA) production, enhanced biofilm formation and increased resistance to different antibiotics when cultivated in Luria Bertani medium at pH 5.3 compared to pH 7.3. Furthermore, B. ambifaria T16 showed distinctive plant growth-promoting features, such as siderophore production, phosphate-solubilization, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, in vitro antagonism against Fusarium spp. and improvement of grain yield when inoculated to barley plants grown under greenhouse conditions. This strain might serve as a new source of metabolites or genes for the development of novel FA-detoxification systems.
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http://dx.doi.org/10.1016/j.micres.2017.09.008DOI Listing
January 2018

Pencil graphite electrodes for improved electrochemical detection of oleuropein by the combination of Natural Deep Eutectic Solvents and graphene oxide.

Electrophoresis 2017 11 25;38(21):2704-2711. Epub 2017 Sep 25.

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina.

A novel methodology is presented for the enhanced electrochemical detection of oleuropein in complex plant matrices by Graphene Oxide Pencil Grahite Electrode (GOPGE) in combination with a buffer modified with a Natural Deep Eutectic Solvent, containing 10% (v/v) of Lactic acid, Glucose and H O (LGH). The electrochemical behavior of oleuropein in the modified-working buffer was examined using differential pulse voltammetry. The combination of both modifications, NADES modified buffer and nanomaterial modified electrode, LGH-GOPGE, resulted on a signal enhancement of 5.3 times higher than the bare electrode with unmodified buffer. A calibration curve of oleuropein was performed between 0.10 to 37 μM and a good linearity was obtained with a correlation coefficient of 0.989. Detection and quantification limits of the method were obtained as 30 and 102 nM, respectively. In addition, precision studies indicated that the voltammetric method was sufficiently repeatable, %RSD 0.01 and 3.16 (n = 5) for potential and intensity, respectively. Finally, the proposed electrochemical sensor was successfully applied to the determination of oleuropein in an olive leaf extract prepared by ultrasound-assisted extraction. The results obtained with the proposed electrochemical sensor were compared with Capillary Zone Electrophoresis analysis with satisfactory results.
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http://dx.doi.org/10.1002/elps.201700173DOI Listing
November 2017

Novel approaches mediated by tailor-made green solvents for the extraction of phenolic compounds from agro-food industrial by-products.

Food Chem 2018 Jan 1;239:671-678. Epub 2017 Jul 1.

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina. Electronic address:

An environmentally friendly method for the phenolic compound extraction from agro-food industrial by-products was developed in order to contribute with their sustainable valorization. A Natural Deep Eutectic Solvent was chemometrically-designed for the first time and compared with traditional solvents in terms of analyte stabilization. The combination of lactic acid, glucose and 15% water (LGH-15) was selected as optimal. A high-efficiency ultrasound-assisted extraction mediated by LGH-15 prior to HPLC-DAD allows the determination of 14 phenols in onion, olive, tomato and pear industrial by-products. NADES synthesis as well as the extraction procedures were optimized by Response Surface Methodology. Thus, phenolic determination in these complex samples was achieved by a simple, non-expensive, eco-friendly and robust system. The application to different matrices demonstrated the versatility of the proposed method. NADES opens interesting perspectives for their potential use as vehicles of bioactive compounds as food additives or pharmaceuticals.
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http://dx.doi.org/10.1016/j.foodchem.2017.06.150DOI Listing
January 2018

Diabetes-Related Cognitive Decline, a Global Health Issue, and New Treatments Approaches.

Int J Priv Health Inf Manag 2017 Jul-Dec;5(2):58-70

Beth Israel Deaconess Medical Center, Boston, MA, USA.

The epidemic of type 2 diabetes (T2DM) is spreading around the globe and challenging the unprecedented success of health sciences in increasing longevity. T2DM has been linked to accelerated brain aging, functional decline in older adults and dementia. Brain insulin resistance and glycemic variability are potential mechanisms underlying T2DM-related brain damage and cognitive decline. Intranasal insulin therapy has emerged as a potential new treatment for T2DM-related cognitive impairment. Wearable technologies now allow better monitoring of behaviors and glycemic levels over several days and deliver real time feedback that can be used to improve self-management and lead to new prevention strategies and therapies for T2DM complications.
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http://dx.doi.org/10.4018/IJPHIM.2017070104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6159895PMC
October 2018

Quantitative Trait Loci and Antagonistic Associations for Two Developmentally Related Traits in the Drosophila Head.

J Insect Sci 2017 Jan 27;17(1). Epub 2017 Jan 27.

Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IEGEBA (CONICET-UBA), Buenos Aires, C-1428-EGA, Argentina.

In insects, some developmentally related traits are negatively correlated. Here, we mapped Quantitative Trait Loci (QTL) for traits of eye size and head capsule, in an intercontinental set of recombinant inbred lines (RILs) of Drosophila melanogaster Composite interval mapping identified QTL on all major chromosomes. Two negatively correlated traits (size of eyes and between-eyes distance) were influenced by one QTL that appeared to be antagonistic between the traits (QTL cytological range is 25F5-30A6), consistent with a negative genetic correlation between these traits of the head capsule. Comparisons of QTL across traits indicated a nonrandom distribution over the genome, with a considerable overlap between some QTL across traits. Developmentally-related traits were influenced by QTL in a pattern that is consistent both with 1) the sign of the genetic correlation between the traits and 2) a constraint in the micro-evolutionary differentiation in the traits.
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http://dx.doi.org/10.1093/jisesa/iew115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5270402PMC
January 2017

Enhanced electrochemical detection of quercetin by Natural Deep Eutectic Solvents.

Anal Chim Acta 2016 Sep 25;936:91-6. Epub 2016 Jul 25.

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina. Electronic address:

New trends in analytical chemistry encourage the development of smart techniques and methods aligned with Green Chemistry. In this sense, Natural Deep Eutectic Solvents represents an excellent opportunity as a new generation of green solvents. In this work a new application for them has been proposed and demonstrated. These solvents were synthesized by combinations of inexpensive and natural components like, Glucose, Fructose, Citric acid and Lactic acid. The different natural solvents were easily prepared and added to buffer solution in different concentrations, allowing the enhancement of electrochemical detection of an important representative antioxidant like quercetin (QR) with improved signal up to 380%. QR is a ubiquitous flavonoid widespread in plants and food of plant origin. The proposed method using phosphate buffer with a eutectic mixture of Citric acid, Glucose and water in combination with carbon screen printed electrodes exhibited a good analytical performance. Detection and quantification limits were of 7.97 and 26.3 nM respectively; and repeatability with %RSDs of 1.41 and 7.49 for peak potential and intensity respectively. In addition, it has proved to be faster, greener and cheaper than other sensors and chromatographic methods available with the additional advantage of being completely portable. Furthermore, the obtained results demonstrated that the proposed method is able for the determination of QR in complex food samples.
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http://dx.doi.org/10.1016/j.aca.2016.07.022DOI Listing
September 2016

Microchip electrophoresis for wine analysis.

Anal Bioanal Chem 2016 Dec 15;408(30):8643-8653. Epub 2016 Aug 15.

IBAM, UNCuyo, CONICET, Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Almirante Brown 500, M5528AHB, Chacras de Coria, Mendoza, Argentina.

The present critical review provides a summary of representative articles describing the analysis of wine by microchip electrophoresis. Special emphasis has been given to those compounds able to provide background information to achieve the differentiation of wines according to botanical origin, provenance, vintage and quality or assure wine authentication. This review focuses on capillary electrophoresis (CE) microchips dedicated to the analysis of wine covering all the contributions concerning this area. The most relevant compounds in wine analysis such as phenols, organic acids, inorganic species, aldehydes, sugars, alcohols, and neuroactive amines were considered. Moreover, a special section is dedicated to the potential of CE microchip for wine classification. Indeed, potential directions for the future are discussed.
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http://dx.doi.org/10.1007/s00216-016-9841-0DOI Listing
December 2016

Elevated extension of longevity by cyclically heat stressing a set of recombinant inbred lines of Drosophila melanogaster throughout their adult life.

Biogerontology 2016 11 3;17(5-6):883-892. Epub 2016 Aug 3.

Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - IEGEBA (CONICET-UBA), C-1428-EHA, Buenos Aires, Argentina.

An extremely high (about 100 %) increase in longevity is reported for a subset of recombinant inbred lines (RILs) of Drosophila melanogaster subjected to a cyclic heat stress throughout the adult life. Previous work showed that both longevity and heat sensitivity highly differed among RILs. The novel heat stress treatment used in this study consisted of 5 min at 38 °C applicated approximately every 125 min throughout the adult life starting at the age of 2 days. In spite of the exceptionally high increase in longevity in a set of RILs, the same heat stress treatment reduced rather than increased longevity in other RILs, suggesting that heat-induced hormesis is dependent on the genotype and/or the genetic background. Further, one quantitative trait locus (QTL) was identified for heat-induced hormesis on chromosome 2 (bands 28A1-34D2) in one RIL panel (RIL-D48) but it was not significant in its reciprocal panel (RIL-SH2). The level of heat-induced hormesis showed a sexual dimorphism, with a higher number of lines exhibiting higher hormesis effects in males than in females. The new heat stress treatment in this study suggests that longevity can be further extended than previously suggested by applying a cyclic and mild stress throughout the life, depending on the genotype.
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http://dx.doi.org/10.1007/s10522-016-9658-4DOI Listing
November 2016

Persistence of Breakage in Specific Chromosome Bands 6 Years after Acute Exposure to Oil.

PLoS One 2016 1;11(8):e0159404. Epub 2016 Aug 1.

Unitat de Biologia Cel·lular i Genètica Mèdica, Facultat de Medicina, Universitat Autònoma de Barcelona (UAB), Bellaterra, Spain.

Background: The identification of breakpoints involved in chromosomal damage could help to detect genes involved in genetic disorders, most notably cancer. Until now, only one published study, carried out by our group, has identified chromosome bands affected by exposure to oil from an oil spill. In that study, which was performed two years after the initial oil exposure in individuals who had participated in clean-up tasks following the wreck of the Prestige, three chromosomal bands (2q21, 3q27, 5q31) were found to be especially prone to breakage. A recent follow-up study, performed on the same individuals, revealed that the genotoxic damage had persisted six years after oil exposure.

Objectives: To determine whether there exist chromosome bands which are especially prone to breakages and to know if there is some correlation with those detected in the previous study. In addition, to investigate if the DNA repair problems detected previously persist in the present study.

Design: Follow-up study performed six years after the Prestige oil spill.

Setting: Fishermen cooperatives in coastal villages.

Participants: Fishermen highly exposed to oil spill who participated in previous genotoxic study six years after the oil.

Measurements: Chromosome damage in peripheral lymphocytes. For accurate identification of the breakpoints involved in chromosome damage of circulating lymphocytes, a sequential stain/G-banding technique was employed. To determine the most break-prone chromosome bands, two statistical methods, the Fragile Site Multinomial and the chi-square tests (where the bands were corrected by their length) were used. To compare the chromosome lesions, structural chromosome alterations and gaps/breaks between two groups of individuals we used the GEE test which takes into account a possible within-individual correlation. Dysfunctions in DNA repair mechanisms, expressed as chromosome damage, were assessed in cultures with aphidicolin by the GEE test.

Results: Cytogenetic analyses were performed in 47 exposed individuals. A total of 251 breakpoints in exposed individuals) were identified, showing a non-uniform distribution in the human ideogram. Ten chromosome bands were found to be especially prone to breakage through both statistical methods. By comparing these bands with those observed in certain exposed individuals who had already participated the previous study, it was found in both studies that four bands (2q21, 3q27, 5q31 and 17p11.2) are particularly sensitive to breakage. Additionally, the dysfunction in DNA repair mechanisms was not significantly higher in oil-exposed individuals than in non-exposed individuals.

Limitations: The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the high number of individuals who participated occasionally in clean-up tasks.

Conclusion: Our findings show the existence of at least four target bands (2q21, 3q27, 5q31 and 17p11.2) with a greater propensity to break over time after an acute exposure to oil. The breaks in these bands, which are commonly involved in hematological cancer, may explain the increase of cancer risk reported in chronically benzene-exposed individuals. In addition, a more efficiency of the DNA repair mechanisms has been detected six years after in fishermen who were highly exposed to the oil spill. To date, only this study, performed by our group on the previous and present genotoxic effects, has analyzed the chromosomal regions affected by breakage after an acute oil exposure.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0159404PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4969035PMC
August 2017

Lack of Correlation Between Pulmonary and Systemic Inflammation Markers in Patients with Chronic Obstructive Pulmonary Disease: A Simultaneous, Two-Compartmental Analysis.

Arch Bronconeumol 2016 Jul 24;52(7):361-7. Epub 2016 Feb 24.

CIBER Enfermedades Respiratorias (CIBERES), España; Institut del Tòrax, Hospital Clínic, IDIBAPS, Universitat de Barcelona, Barcelona, España.

Introduction: The origin of systemic inflammation in chronic obstructive pulmonary disease (COPD) patients remains to be defined, but one of the most widely accepted hypothesis is the 'spill over' of inflammatory mediators from the lung to the circulation.

Objective: To evaluate the relationship between pulmonary and systemic inflammation in COPD quantifying several inflammatory markers in sputum and serum determined simultaneously.

Methodology: Correlations between various inflammatory variables (TNF-α, IL6, IL8) in sputum and serum were evaluated in 133 patients from the PAC-COPD cohort study. A secondary objective was the evaluation of relationships between inflammatory variables and lung function.

Results: Inflammatory markers were clearly higher in sputum than in serum. No significant correlation was found (absolute value, r=0.03-0.24) between inflammatory markers in blood and in sputum. There were no significant associations identified between those markers and lung function variables, such as FEV1, DLCO and PaO2 neither.

Conclusions: We found no correlation between pulmonary and systemic inflammation in patients with stable COPD, suggesting different pathogenic mechanisms.
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http://dx.doi.org/10.1016/j.arbres.2016.01.003DOI Listing
July 2016

Follow-Up Genotoxic Study: Chromosome Damage Two and Six Years after Exposure to the Prestige Oil Spill.

PLoS One 2015 29;10(7):e0132413. Epub 2015 Jul 29.

Unitat de Biologia Cel·lular i Genètica Mèdica, Facultat de Medicina, Universitat Autònoma de Barcelona (UAB), Bellaterra, Spain.

Background: The north-west coast of Spain was heavily contaminated by the Prestige oil spill, in 2002. Individuals who participated in the clean-up tasks showed increased chromosome damage two years after exposure. Long-term clinical implications of chromosome damage are still unknown.

Objective: To realize a follow-up genotoxic study to detect whether the chromosome damage persisted six years after exposure to the oil.

Design: Follow-up study.

Setting: Fishermen cooperatives in coastal villages.

Participants: Local fishermen who were highly exposed (n = 52) and non-exposed (n = 23) to oil seven years after the spill.

Measurements: Chromosome damage in circulating lymphocytes.

Results: Chromosome damage in exposed individuals persists six years after oil exposure, with a similar incidence than those previously detected four years before. A surprising increase in chromosome damage in non-exposed individual was found six years after Prestige spill vs. those detected two years after the exposure.

Limitations: The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the approximately 300,000 individuals who participated occasionally in clean-up tasks.

Conclusion: The persistence of chromosome damage detected in exposed individuals six years after oil exposure seems to indicate that the cells of the bone marrow are affected. A surprising increase in chromosome damage in non-exposed individuals detected in the follow-up study suggests an indirect exposition of these individuals to some oil compounds or to other toxic agents during the last four years. More long-term studies are needed to confirm the presence of chromosome damage in exposed and non-exposed fishermen due to the association between increased chromosomal damage and increased risk of cancer. Understanding and detecting chromosome damage is important for detecting cancer in its early stages. The present work is the first follow-up cytogenetic study carried out in lymphocytes to determine genotoxic damage evolution between two and six years after oil exposure in same individuals.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0132413PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4519162PMC
April 2016

Melatonin in Arabidopsis thaliana acts as plant growth regulator at low concentrations and preserves seed viability at high concentrations.

Plant Physiol Biochem 2015 Sep 12;94:191-6. Epub 2015 Jun 12.

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina. Electronic address:

Since the discovery of melatonin in plants, several roles have been described for different species, organs, and developmental stages. Arabidopsis thaliana, being a model plant species, is adequate to contribute to the elucidation of the role of melatonin in plants. In this work, melatonin was monitored daily by UHPLC-MS/MS in leaves, in order to study its diurnal accumulation as well as the effects of natural and artificial light treatments on its concentration. Furthermore, the effects of exogenous application of melatonin to assess its role in seed viability after heat stress and as a regulator of growth and development of vegetative tissues were evaluated. Our results indicate that melatonin contents in Arabidopsis were higher in plants growing under natural radiation when compared to those growing under artificial conditions, and its levels were not diurnally-regulated. Exogenous melatonin applications prolonged seed viability after heat stress conditions. In addition, melatonin applications retarded leaf senescence. Its effects as growth promoter were dose and tissue-dependent; stimulating root growth at low concentrations and decreasing leaf area at high doses.
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http://dx.doi.org/10.1016/j.plaphy.2015.06.011DOI Listing
September 2015

Utility of noninvasive arrhythmia mapping in patients with adult congenital heart disease.

Card Electrophysiol Clin 2015 Mar;7(1):117-23

Department of Cardiology, Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK.

Arrhythmia management in patients with adult congenital heart disease (ACHD) is a challenge on many levels, as tachycardic episodes may lead to hemodynamic impairment in otherwise compensated patients even if episodes are only transient. Recently several technical advances, including 3-dimensional (3D) image integration, 3D mapping, and remote magnetic navigation, have been introduced to facilitate curatively intended ablation procedures in patients with ACHD. This review attempts to outline the role of a novel technology of simultaneous, noninvasive mapping in this patient cohort, and gives details of the authors' single-center experience.
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http://dx.doi.org/10.1016/j.ccep.2014.11.007DOI Listing
March 2015

Microchip electrophoresis-single wall carbon nanotube press-transferred electrodes for fast and reliable electrochemical sensing of melatonin and its precursors.

Electrophoresis 2015 Aug 21;36(16):1880-5. Epub 2015 Apr 21.

Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, Alcalá de Henares, Madrid, Spain.

In the current work, single-wall carbon nanotube press-transferred electrodes (SW-PTEs) were used for detection of melatonin (MT) and its precursors tryptophan (Trp) and serotonin (5-HT) on microchip electrophoresis (ME). SW-PTEs were simply fabricated by press transferring a filtered dispersion of single-wall carbon nanotubes on a nonconductive PMMA substrate, where single-wall carbon nanotubes act as exclusive transducers. The coupling of ME-SW-PTEs allowed the fast detection of MT, Trp, and 5-HT in less than 150 s with excellent analytical features. It exhibited an impressive antifouling performance with RSD values of ≤2 and ≤4% for migration times and peak heights, respectively (n = 12). In addition, sample analysis was also investigated by analysis of 5-HT, MT, and Trp in commercial samples obtaining excellent quantitative and reproducible recoveries with values of 96.2 ± 1.8%, 101.3 ± 0.2%, and 95.6 ± 1.2% for 5-HT, MT, and Trp, respectively. The current novel application reveals the analytical power of the press-transfer technology where the fast and reliable determination of MT and its precursors were performed directly on the nanoscale carbon nanotube detectors without the help of any other electrochemical transducer.
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http://dx.doi.org/10.1002/elps.201400580DOI Listing
August 2015

Determinants of exercise capacity in obese and non-obese COPD patients.

Respir Med 2014 May 12;108(5):745-51. Epub 2014 Feb 12.

Servei de Pneumologia (ICT), Hospital Clinic, IDIBAPS, Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Universitat de Barcelona, Villaroel 170, 08036 Barcelona, Catalonia, Spain.

Background: The effects of obesity in combination with chronic obstructive pulmonary disease (COPD) on exercise capacity are receiving increased attention. But, a comprehensive analysis of factors associated with aerobic capacity in obese COPD patients has not been performed.

Methods: Six-min walking test (6MWT) was performed in 251 COPD patients, and 159 of those also carried out an incremental cardiopulmonary exercise test (CPET) to evaluate exercise capacity. In all patients, anthropometrics, dyspnea and anxiety-depression scores, lung function, daily physical activity, co-morbidities and circulating inflammatory biomarkers were also assessed. Six-min walking distance (6MWD) and peak oxygen uptake (VO2 peak) during CPET were two primary outcome variables.

Results: 57% of the patients showed body mass index (BMI) < 30 kg/m2 (COPDN) and the remaining 43% were obese with a BMI ≥ 30 kg/m2 (COPDO). In patients with COPDN, 6MWD showed independent negative associations with age, dyspnea score, sedentarism, depression scores and a positive relationship with arterial oxygenation; whereas in COPDO, 6MWD showed an inverse relationship with BMI. In COPDN, VO2 peak showed a negative association with age and positive relationships with both FEV1 and DLCO. However, in COPDO the dyspnea score was the strongest determinant of VO2 peak.

Conclusions: Obese and non-obese COPD patients show different determinants of aerobic capacity, including pulmonary and non-pulmonary factors that are also dependent on the type of exercise protocol. These results could be considered in the evaluation of obese patients with COPD.
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http://dx.doi.org/10.1016/j.rmed.2014.02.004DOI Listing
May 2014

Hospital admissions and exercise capacity decline in patients with COPD.

Eur Respir J 2014 Apr 3;43(4):1018-27. Epub 2014 Jan 3.

and a list of the PAC-COPD Study Group members and their affiliations, see the Acknowledgements.

Exercise capacity declines with time and is an important determinant of health status and prognosis in patients with chronic obstructive pulmonary disease (COPD). We hypothesised that hospital admissions are associated with exercise capacity decline in these patients. Clinical and functional variables were collected for 342 clinically stable COPD patients. The 6-min walk distance (6MWD) was determined at baseline and after a mean±sd of 1.7±0.3 years. Information on hospitalisations during follow-up was obtained from centralised administrative databases. Linear regression was used to model changes in exercise capacity. Patients were mostly male (92%), with mean±sd age 67.9±8.6 years, post-bronchodilator forced expiratory volume in 1 s 54±17% predicted and baseline 6MWD 433±93 m. During follow-up, 6MWD decreased by 21.9±51.0 m·year(-1) and 153 (45%) patients were hospitalised at least once. Among patients admitted only for COPD-related causes (50% of those ever admitted), the proportion presenting a clinically significant loss of 6MWD was higher than in patients admitted for only nonrespiratory conditions (53% versus 29%, p=0.040). After adjusting for confounders, annual 6MWD decline was greater (26 m·year(-1), 95% CI 13-38 m·year(-1); p<0.001) in patients with more than one all-cause hospitalisation per year, as compared with those with no hospitalisations. Hospitalisations are related to a greater decline in exercise capacity in COPD.
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http://dx.doi.org/10.1183/09031936.00088313DOI Listing
April 2014

Chromosomal bands affected by acute oil exposure and DNA repair errors.

PLoS One 2013 26;8(11):e81276. Epub 2013 Nov 26.

Unitat de Biologia Cel·lular i Genètica Mèdica, Facultat de Medicina, Universitat Autònoma de Barcelona (UAB), Bellaterra, Spain.

Background: In a previous study, we showed that individuals who had participated in oil clean-up tasks after the wreckage of the Prestige presented an increase of structural chromosomal alterations two years after the acute exposure had occurred. Other studies have also reported the presence of DNA damage during acute oil exposure, but little is known about the long term persistence of chromosomal alterations, which can be considered as a marker of cancer risk.

Objectives: We analyzed whether the breakpoints involved in chromosomal damage can help to assess the risk of cancer as well as to investigate their possible association with DNA repair efficiency.

Methods: Cytogenetic analyses were carried out on the same individuals of our previous study and DNA repair errors were assessed in cultures with aphidicolin.

Results: Three chromosomal bands, 2q21, 3q27 and 5q31, were most affected by acute oil exposure. The dysfunction in DNA repair mechanisms, expressed as chromosomal damage, was significantly higher in exposed-oil participants than in those not exposed (p= 0.016).

Conclusion: The present study shows that breaks in 2q21, 3q27 and 5q31 chromosomal bands, which are commonly involved in hematological cancer, could be considered useful genotoxic oil biomarkers. Moreover, breakages in these bands could induce chromosomal instability, which can explain the increased risk of cancer (leukemia and lymphomas) reported in chronically benzene-exposed individuals. In addition, it has been determined that the individuals who participated in clean-up of the oil spill presented an alteration of their DNA repair mechanisms two years after exposure.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0081276PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3841120PMC
October 2014

Pulmonary vascular abnormalities in chronic obstructive pulmonary disease undergoing lung transplant.

J Heart Lung Transplant 2013 Dec;32(12):1262-9

Servei de Pneumologia (Institut del Tòrax), Hospital Clínic, Institut d'Investigacions Biomédiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Ciber Enfermedades Respiratories. Electronic address:

Background: Little is known about the structure and function relationships of pulmonary vessels in the most severe chronic obstructive pulmonary disease (COPD) spectrum. We investigated morphometric, cellular, and physiologic characteristics of pulmonary arteries from COPD patients undergoing bilateral lung transplant.

Methods: Seventeen patients with very severe COPD (forced expiratory volume in 1 second, 24% ± 7%) were assessed using inert gas exchange and pulmonary hemodynamics while breathing ambient air and 100% oxygen. Morphometry, in vitro reactivity to hypoxia, and inflammatory cell counts of pulmonary arteries were measured in explanted lungs.

Results: Patients had moderate ventilation-perfusion imbalance along with mild release of hypoxic pulmonary vasoconstriction. Mild pulmonary hypertension was observed in 7 patients. Explanted lungs had predominant emphysema with mild small airway involvement. In vitro reactivity was modestly altered, with relatively preserved endothelium-dependent relaxation, and vascular remodelling was discrete, with intense CD8+ T lymphocytes infiltrate. In vitro reactivity correlated with pulmonary vascular resistance (on ambient air) and oxygen-induced pulmonary artery pressure changes. Patients with pulmonary hypertension had more severe morphologic and physiologic emphysema.

Conclusions: In end-stage COPD patients undergoing lung transplant, pulmonary vascular involvement is unexpectedly modest, with low-grade endothelial dysfunction. In this sub-set of COPD patients, pulmonary emphysema may constitute the major determinant of the presence of pulmonary hypertension.
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http://dx.doi.org/10.1016/j.healun.2013.09.007DOI Listing
December 2013

Evaluation of the persistence of functional and biological respiratory health effects in clean-up workers 6 years after the prestige oil spill.

Environ Int 2014 Jan 26;62:72-7. Epub 2013 Oct 26.

Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address:

Fishermen who had participated in clean-up activities of the Prestige oil spill showed increased bronchial responsiveness and higher levels of respiratory biomarkers 2 years later. We aimed to evaluate the persistence of these functional and biological respiratory health effects 6 years after clean-up work. In 2008/2009 a follow-up study was done in 230 never-smoking fishermen who had been exposed to clean-up work in 2002/2003 and 87 non-exposed fishermen. Lung function and bronchial responsiveness testing and the determination of respiratory biomarkers in exhaled breath condensate were done identically as in the baseline survey in 2004/2005. Associations between participation in clean-up work and respiratory health parameters were assessed using linear and logistic regression analyses adjusting for sex and age. Information from 158 exposed (69%) and 57 non-exposed (66%) fishermen was obtained. Loss to follow-up in the non-exposed was characterised by less respiratory symptoms at baseline. During the 4-year follow-up period lung function, bronchial hyperresponsiveness and the levels of respiratory biomarkers of oxidative stress and growth factors had deteriorated notably more among non-exposed than among exposed. At follow-up, respiratory health indices were similar or better in clean-up workers than in non-exposed. No clear differences between highly exposed and moderately exposed clean-up workers were found. In conclusion, we could not detect long-term respiratory health effects in clean-up workers 6 years after the Prestige oil spill. Methodological issues that need to be considered in this type of studies include the choice of a non-exposed control group and limitation of follow-up to subgroups such as never smokers.
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http://dx.doi.org/10.1016/j.envint.2013.09.020DOI Listing
January 2014

Effects of dietary composition on life span of Drosophila buzzatii and its short-lived sibling species D. koepferae.

Biogerontology 2013 Aug 9;14(4):423-9. Epub 2013 Jul 9.

Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires-IEGEBA, Argentina.

Two sibling Drosophila species dramatically divergent in longevity, Drosophila buzzatii and D. koepferae, were examined for possible effects of both developmental culture medium and dietary composition (DC) on longevity. Longevity was greatly increased in the longer lived D. buzzatii when flies were reared and fed on a rich-in-nutrient and cactus-based culture (R-CBC) as compared to longevity in a poor nutrient culture (PNC). In D. buzzatii, life span was further increased by exposing flies to short periods of a poor-in-nutrient and cactus-based culture (P-CBC). In contrast, variation in the here used nutrient composition did not change life span in the shorter lived D. koepferae, as longevity in this species did not differ among R-CBC, P-CBC and PNC cultures. Hormesis is a plausible explanation for the beneficial biological effects against aging arising from brief exposure to a lowed calorie food source in D. buzzatii. This study shows that genetic variation between closely related species is substantial for dietary effects on longevity.
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http://dx.doi.org/10.1007/s10522-013-9441-8DOI Listing
August 2013

Analytical tools for elucidating the biological role of melatonin in plants by LC-MS/MS.

Electrophoresis 2013 Jun 20;34(12):1749-56. Epub 2013 May 20.

Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina.

Melatonin (MT) presence in higher plants was recently discovered and the knowledge of its function in vivo is limited. Several studies have recently shown the occurrence of MT and related compounds in grapes and wines. The analysis of MT in plants and foods represents a highly challenging task due to its wide concentration range, the difficulty in the selection of the extraction solvents because of its amphipathic nature, and the fact that it reacts quickly with other matrix components. Thus, sample processing factors; preparation/cleanup procedures; and chromatographic/detection parameters, such as HILIC and reverse phase (C(8) and C(18)) chromatographic modes, ESI, and atmospheric pressure chemical ionization (APCI) in both negative and positive modes were evaluated. Taken together, we have demonstrated that optimal conditions were quite different for each of the matrices under study. A sonication-mediated extraction step was necessary for grape skin (100% v/v methanol) and plant tissues (50% v/v methanol), while wine and must required a SPE preconcentration step. HILIC-(+) APCI ionization was better for MT standards, while C(8) -(+) APCI was the best choice for grape skin and C(18) -(+ESI) was suitable for wine. On the other hand, C(8) -(+)ESI was the most appropriate for vegetal tissues of Arabidopsis thaliana. Proposed methods were validated and the LODs were in the low picogram levels range. The optimized approaches were applied to the determination of MT and its isomer in different vegetal/food samples; levels found within the range: 4.9-440 ng/g.
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http://dx.doi.org/10.1002/elps.201200569DOI Listing
June 2013

Risk assessment on irrigation of Vitis vinifera L. cv Malbec with Hg contaminated waters.

Environ Sci Technol 2013 Jun 28;47(12):6606-13. Epub 2013 May 28.

Instituto de Biología Agrícola de Mendoza, IBAM-CONICET, Alte.Brown 500, Chacras de Coria, CP 5505 Mendoza, Argentina.

Concerns regard watering crops with Hg contaminated waters have arisen worldwide recently. In these sense Hg uptake by Vitis vinifera L. cv. Malbec was evaluated under greenhouse conditions by the administration of Hg(2+) for 4 days through irrigation water (short-term administration). Vines uptake Hg translocating it from roots through stems to leaves. Roots accumulated the higher Hg concentration. Hg in stems and leaves was accumulated mostly as organic Hg, bind to different moieties. Size exclusion chromatography (SEC) and ion pair chromatography (IPC) were employed to reach insights into these ligands. Hg is distributed mainly in high molecular weight fractions of 669 kDa in vine plants. In stems and leaves, Hg-S associations were found in 669 and 66 kDa fractions. Hg-S association at 66 kDa suggests a possible protein or peptide binding affecting vines normal physiology. Since Hg contamination through organomercurials is more harmful than Hg(2+) itself, methyl mercury, dimethyl mercury, and phenyl mercury, more toxic Hg species were evaluated with negative results.
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http://dx.doi.org/10.1021/es3047476DOI Listing
June 2013

Effect of nitric oxide inhalation on gas exchange in acute severe pneumonia.

Respir Physiol Neurobiol 2013 Jun 26;187(2):157-63. Epub 2013 Mar 26.

Department of Pulmonary Medicine, Institut Clínic del Tórax, Hospital Clínic, University of Barcelona, Barcelona, Spain.

Inhaled nitric oxide (NO) causes selective pulmonary vasodilatation and may improve gas exchange. The study was aimed to evaluate the acute effects of inhaled NO on pulmonary gas exchange in severe unilateral pneumonia, where hypoxemia results from increased intrapulmonary shunt. We studied 8 patients without preexisting lung disease (59±18 yr; 4M/4F) with early unilateral severe pneumonia and respiratory failure. Pulmonary and systemic hemodynamics and gas exchange, including ventilation-perfusion (V;A/Q;) distributions, were measured at baseline and while breathing 5 and 40 parts per million (ppm) of NO. Inhaled NO caused a dose-dependent fall in pulmonary vascular resistance (by 12% and 21%, with 5 and 40ppm, respectively; p<0.01, each) and improvement of PaO2 (by 25% and 23%; p<0.05, each), owing to the reduction of intrapulmonary shunt (by 23% and 27%; p<0.05, each), without changes in the amount of perfusion to low V;A/Q; ratio alveolar units. Patients with greater baseline intrapulmonary shunt exhibited greater improvement in arterial oxygenation (r(2)=0.55, p<0.05). We conclude that low doses of inhaled NO improve pulmonary gas exchange in acute severe pneumonia.
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http://dx.doi.org/10.1016/j.resp.2013.03.006DOI Listing
June 2013

Functional and biological characteristics of asthma in cleaning workers.

Respir Med 2013 May 20;107(5):673-83. Epub 2013 Feb 20.

Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.

Objectives: Cleaning workers have an increased risk of asthma but the underlying mechanisms are largely unknown. We studied functional and biological characteristics in asthmatic cleaners and compared these to healthy cleaners.

Methods: Forty-two cleaners with a history of asthma and/or recent respiratory symptoms and 53 symptom-free controls were identified. Fractional exhaled nitric oxide (FeNO) was measured and forced spirometry with reversibility testing was performed. Total IgE, pulmonary surfactant protein D and the 16 kDa Clara Cell secretory protein were measured in blood serum. Interleukins and other cytokines, growth factors, cys-leukotrienes and 8-isoprostane were measured in exhaled breath condensate. Information on occupational and domestic use of cleaning products was obtained in an interview. Associations between asthma status, specific characteristics and the use of cleaning products were evaluated using multivariable linear and logistic regression analyses.

Results: Asthma was associated with an 8% (95% confidence interval (CI) 1-15%) lower postbronchodilator FEV1, a higher prevalence of atopy (42% vs. 10%) and a 2.9 (CI 1.5-5.6) times higher level of total IgE. Asthma status was not associated with the other respiratory biomarkers. Most irritant products and sprays were more often used by asthmatic cleaners. The use of multiuse products, glass cleaners and polishes at work was associated with higher FeNO, particularly in controls.

Conclusions: Asthma in cleaning workers is characterised by non-reversible lung function decrement and increased total IgE. Oxidative stress, altered lung permeability and eosinophilic inflammation are unlikely to play an important underlying role, although the latter may be affected by certain irritant cleaning exposures.
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http://dx.doi.org/10.1016/j.rmed.2013.01.011DOI Listing
May 2013