Search the repository

A+ | A- | | SLO | ENG

Abstract: Background: The environment in swimming pools, which contain chlorine, might interact with the airway epithelium, resulting in oxidative stress and/or inflammation during high intensity training periods. Methods: We evaluated pulmonary functional (metacholine challenge test, FEV1 and VC), cellular (eosinophils and neutrophils), inflammatory (FeNo, IL-5, IL-6, IL-8 and TNF-[alpha]), oxidative (8-isoprostanes) and angiogenesis factors (VEGF) in induced sputum and peripheral blood of 41 healthy non-asthmatic elite swimmers (median 16 years) during the period of high intensity training before a national championship. The second paired sampling was performed seven months later after training had been stopped for one month. Results: There was a ten-fold increase (median 82-924 pg/ml; P < 0.001) in 8-isoprostanes in induced sputum and five-fold increase (median 82-924 pg/ml; P < 0.001) in sera during training in comparison to the period of rest. However, there was no difference in FEV1 (113 vs 116%), VC (119 vs 118%), FeNo (median 34 vs 38 ppb), eosinophils (2.7 vs 2.9% in sputum; 180 vs 165 cells/[micro]l in blood), neutrophils, different cytokines or VEGF in induced sputum or sera. The only exception was TNF-[alpha], which was moderately increased in sera (median 23 vs 40 pg/ml; P=0.02) during the peak training period. Almost half (18 of 41) of swimmers showed bronchial hyperresponsiveness during the peak training period (PC20 cutoff was 4 mg/ml). There was no correlation between hyperresponsiveness and the markers of oxidative stress or inflammation. Conclusions: High intensity training in healthy, non-asthmatic competitive swimmers results in marked oxidative stress at the airway and systemic levels, but does not lead to airway inflammation. However, we could not confirm that oxidative stress is associated with bronchial hyperresponsiveness (AHR), which is often observed during the peak exercise training period.
Keywords: bronchial diseases, swimming, oxidative stress, bronchial hyperresponsiveness, competitive swimmers, training
Published in DiRROS: 23.11.2020; Views: 1736; Downloads: 471
Link to file

Abstract: Crop plants are subjected to various biotic and abiotic stresses. Both root-knot nematodes (biotic stress) and water deficiency (abiotic stress) lead to similar drought symptoms in the plant canopy. In this work, hyperspectral imaging was used for early detection of nematode infestation and water deficiency (drought) stress in tomato plants. Hyperspectral data in the range from 400 to 2500 nm of plants subjected to different watering regimes and nematode infestation levels were analysed by partial least squares – discriminant analysis (PLS-DA) and partial least squares – support vector machine (PLS-SVM) classification. PLS-SVM classification achieved up to 100% accuracy differentiating between well-watered and water-deficient plants, and between 90 and 100% when identifying nematode-infested plants. Grouping the data according to the time of imaging increased the accuracy of classification. Shortwave infrared spectral regions associated with the OH and CH stretches were most relevant for the identification of nematode infested plants and severity of infestation. This study demonstrates the capability of hyperspectral imaging to identify and discriminate between biotic and abiotic plant stresses.
Keywords: nematode, Hyperspectral imaging, Drought stress, Root-knot nematode, Tomato
Published in DiRROS: 20.07.2018; Views: 3899; Downloads: 2407
Full text (847,87 KB)
This document has many files! More...