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Exposure assessment to ochratoxin A in Catalonia (Spain) based on the consumption of cereals, nuts, coffee, wine, and beer

  • Coronel, María Bernarda
  • Marín Sillué, Sònia
  • Cano Sancho, German
  • Ramos Girona, Antonio J.
  • Sanchís Almenar, Vicente
Ochratoxin A (OTA) was analysed in composite samples of cereal-based baby foods, beer, breakfast cereals (corn- and rice and wheat-based), loaf bread, peanuts and pistachios. Foodstuffs were collected in hypermarkets and supermarkets from 12 cities in the Spanish region of Catalonia, and composite samples were prepared for analysis involving liquid–liquid extraction, followed by immunoaffinity column clean-up and HPLC with fluorescence detection. Consumption data for the selected foodstuffs were collected by means of a food-frequency questionnaire. The studied population was grouped by age in infants, children, adolescents and adults; and exposure to OTA through the specified foodstuffs, and through wine and coffee, was assessed. Exposure assessment was done through deterministic and probabilistic modelling of the contamination and consumption data. OTA occurrence and mean of positive samples (ng g−1 or ng ml−1, for beer) were the following: 8.7% and 0.233 in baby foods; 88.7% and 0.022 in beer; 2.8% and 0.728 in corn-based breakfast cereals; 25% and 0.293 in wheat-based breakfast cereals; 12.9% and 0.283 in loaf bread; 41.7% and 0.241 in peanuts; and 2.9% and 0.228 in pistachios. The median estimated daily intake of OTA through the foodstuffs by each age group were below the latest provisional tolerable daily intakes (PTDIs) of 17 and 14 ng kg−1 bw day−1 recommended by the European Food Safety Authority (EFSA) in 2006 and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 2007, respectively, ranging from 1% and 2% of those values in adolescents and children, to 3% and 11% in adults and infants.
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Relationships between big five personality factors and values

  • Aluja Fabregat, Antón
  • García Rodríguez, Luis Francisco
An analysis of principal components showed a robust structure of three factors formed by 25 of the 30 values studied. These factors were called Social Power, Order and Benevolence values. Those factors match with some of Schwartz’s (1992) types of values. Sex differences and correlations between traits and values replicate other authors’ findings. Path analysis results, performed separately for females and males, yielded a better fit for the female than for the male group. However, although there were no substantial differences with regard to the prediction of Surgency, Conscientiousness, Unfriendliness and Neuroticism, Order values (order, neatness, responsibility) for males and Social Power values (power, prestige, fame) for females predicted the Intellect trait. This pattern of results is discussed in relation to changes in gender roles.
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Relationship between empathy and the big five personality traits in a sample of Spanish adolescents

  • Barrio, María Victoria del
  • Aluja Fabregat, Antón
  • García Rodríguez, Luis Francisco
Empathy has been considered a central feature of our temperamental dispositions in childhood and adolescence. It plays a central role in the development of prosocial behavior and moral reasoning. However, the links between empathy and the major factors of personality have not yet been well described. This study explores the relationships between an index of empathy and the Big-Five personality model in a sample of 832 Spanish adolescents. As expected, results show that empathy correlates strongly with Friendliness. Positive correlations with Conscientiousness, Energy, and Openness traits have also been observed, but regression analyses show that relationships of empathy with those three factors were of negligible importance. Contrary to expectations, empathy did not correlate with Emotional stability. This pattern of results was replicated across boys and girls.
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Intraspecific variability of growth and patulin production of 79 Penicillium expansum isolates at two temperatures

  • Garcia, Daiana
  • Ramos Girona, Antonio J.
  • Sanchís Almenar, Vicente
  • Marín Sillué, Sònia
Penicillium expansum is the main species responsible for patulin production in apples and pears. Generally, fruit is stored at suboptimal conditions for mould growth and this situation could influence on the intra-species variability in both capability for growth and mycotoxin production. The aim of this research was to assess the impact of suboptimal environmental conditions on the intra-specific variability of P. expansum growth and patulin production using seventy nine isolates of this mould. Petri dishes with Apple Concentrate Agar Medium (ACAM) were inoculated centrally and incubated at two temperatures, one near optimal (20 °C) and the other representative of suboptimal cold storage (1 °C). For each condition, 10 Petri dishes were inoculated, and colony growth and patulin production was measured over time. The Kruskal–Wallis test revealed significant differences among growth rate (μ) and lag phase (λ) within the seventy nine assayed isolates. Coefficients of variation revealed a wider dispersion of μ (mm/day) and λ (days) at 1 °C compared with 20 °C. There were significant differences (p < 0.05) among patulin levels (ng/mm2) for the different conditions, values being lower at the lower temperature. Coefficients of variation revealed a wider dispersion of mycotoxin production at 1 °C. In order to address the strain variability in growth initiation and prove the well-established notion of reducing patulin production in foods by preventing fungal growth, a greater number of strains should be included.
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Harvester ant (Messor barbarus (L.)) density as related to soil properties, topography and management in semi-arid cereals

  • Baraibar Padró, Bàrbara
  • Torra Farré, Joel
  • Westerman, Paula Renate
Harvester ants are important weed seed predators in semi-arid cereal fields. Densities of harvester ants vary considerably across fields and so do concomitant weed seed predation rates, however, causes for variability are largely unknown. Understanding the factors that affect ant density may help to identify areas where high natural weed seed control is likely and management factors that could help to enhance ant densities where they are low. Messor barbarus ant density was approximated by estimates of nest density and nest size, and these were correlated to different edaphic, topographic and crop management factors in 34 no-till and 6 minimally tilled cereal fields. The number of years since conversion to no-till explained 12.6% of variability in ant nest density. No other variable could explain nest densities. M. barbarus ant and nest densities increased with increasing number of years of no-till, reached a peak at 11–12 years, after which densities decreased again. Overcompensation by a large cohort of newly established queens could provide an explanation for this observation. Other factors not included in this study, in particular food (seeds) availability, may play an additional role in determining ant density.
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Endonuclease G is a novel determinant of cardiac hypertrophy and mitochondrial function

  • McDermott Roe, Chris
  • Ye, Junmei
  • Ahmed, Rizwan
  • Sun, Xi-Ming
  • Serafín, Anna
  • Ware, James
  • Bottolo, Leonardo
  • Muckett, Phil
  • Cañas, Xavier
  • Zhang, Jisheng
  • Rowe, Glenn C.
  • Buchan, Rachel
  • Lu, Han
  • Braithwaite, Adam
  • Mancini, Massimiliano
  • Hauton, David
  • Martí, Ramon
  • García Arumí, Elena
  • Hubner, Norbert
  • Jacob, Howard
  • Serikawa, Tadao
  • Zidek, Vaclav
  • Papousek, Frantisek
  • Kolar, Frantisek
  • Cardona Colom, Maria
  • Ruiz Meana, Marisol
  • García Dorado, David
  • Comella i Carnicé, Joan Xavier
  • Felkin, Leanne E.
  • Barton, Paul J. R.
  • Zoltan Arany
  • Pravenec, Michal
  • Petretto, Enrico
  • Sanchis, Daniel
  • Cook, Stuart A.
Left ventricular mass (LVM) is a highly heritable trait1 and an independent risk factor for all-cause mortality2. So far, genome-wide association studies have not identified the genetic factors that underlie LVM variation3, and the regulatory mechanisms for blood-pressure-independent cardiac hypertrophy remain poorly understood4, 5. Unbiased systems genetics approaches in the rat6, 7 now provide a powerful complementary tool to genome-wide association studies, and we applied integrative genomics to dissect a highly replicated, blood-pressure-independent LVM locus on rat chromosome 3p. Here we identified endonuclease G (Endog), which previously was implicated in apoptosis8 but not hypertrophy, as the gene at the locus, and we found a loss-of-function mutation in Endog that is associated with increased LVM and impaired cardiac function. Inhibition of Endog in cultured cardiomyocytes resulted in an increase in cell size and hypertrophic biomarkers in the absence of pro-hypertrophic stimulation. Genome-wide network analysis unexpectedly implicated ENDOG in fundamental mitochondrial processes that are unrelated to apoptosis. We showed direct regulation of ENDOG by ERR-α and PGC1α (which are master regulators of mitochondrial and cardiac function)9, 10, 11, interaction of ENDOG with the mitochondrial genome and ENDOG-mediated regulation of mitochondrial mass. At baseline, the Endog-deleted mouse heart had depleted mitochondria, mitochondrial dysfunction and elevated levels of reactive oxygen species, which were associated with enlarged and steatotic cardiomyocytes. Our study has further established the link between mitochondrial dysfunction, reactive oxygen species and heart disease and has uncovered a role for Endog in maladaptive cardiac hypertrophy.
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Ochratoxin A in adult population of Lleida, Spain: presence in blood plasma and consumption in different regions and seasons

  • Coronel, María Bernarda
  • Sanchís Almenar, Vicente
  • Ramos Girona, Antonio J.
  • Marín Sillué, Sònia
Ochratoxin A (OTA) levels in blood plasma, as well as the consumption of possibly contaminated foodstuffs by adult inhabitants, were determined in three seasons in the plain and the mountain regions of the province of Lleida (Spain). Daily intake of the toxin was estimated in order to evaluate the exposure of the studied population. OTA was extracted from plasma through liquid–liquid extraction followed by immunoaffinity chromatography columns clean-up. Detection was done through HPLC-fluorescence, and limit of detection was 0.018 ng/mL. Consumption data of the participants were obtained by means of a food frequency questionnaire. Occurrence of OTA in plasma was 100%. Range was 0.06–10.92 ng/mL, and median was 0.50 ng/mL. Differences between genders, regions or seasons were not significant, whereas significant differences were found among age groups. Regarding food consumption, significant differences were found between genders, but not between age groups, regions, or seasons. OTA plasma levels were not correlated with food consumption. Distributions of the intake estimations based on plasma levels differed from those based on food consumption and contamination. Mean and median values of the daily intake estimations were below the latest provisional tolerable daily intake of 14 ng/kg bw/day, but some high percentiles were above it.
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Oxidative damage compromises energy metabolism in the axonal degeneration mouse model of X-Adrenoleukodystrophy

  • Fourcade, Stéphane
  • Schlüter, Agatha
  • López Erauskin, Jone
  • Guilera, Cristina
  • Jové Font, Mariona
  • Naudí i Farré, Alba
  • García Arumí, Elena
  • Andreu, Antoni L.
  • Starkov, Anatoly A.
  • Pamplona Gras, Reinald
  • Ferrer, Isidre
  • Portero Otín, Manuel
  • Pujol, Aurora
Aims: Chronic metabolic impairment and oxidative stress are associated with the pathogenesis of axonal dysfunction in a growing number of neurodegenerative conditions. To investigate the intertwining of both noxious factors, we have chosen the mouse model of adrenoleukodystrophy (X-ALD), which exhibits axonal degeneration in spinal cords and motor disability. The disease is caused by loss of function of the ABCD1 transporter, involved in the import and degradation of very long-chain fatty acids (VLCFA) in peroxisomes. Oxidative stress due to VLCFA excess appears early in the neurodegenerative cascade. Results: In this study, we demonstrate by redox proteomics that oxidative damage to proteins specifically affects five key enzymes of glycolysis and TCA (Tricarboxylic acid) cycle in spinal cords of Abcd1− mice and pyruvate kinase in human X-ALD fibroblasts. We also show that NADH and ATP levels are significantly diminished in these samples, together with decrease of pyruvate kinase activities and GSH levels, and increase of NADPH. Innovation: Treating Abcd1− mice with the antioxidants N-acetylcysteine and α-lipoic acid (LA) prevents protein oxidation; preserves NADH, NADPH, ATP, and GSH levels; and normalizes pyruvate kinase activity, which implies that oxidative stress provoked by VLCFA results in bioenergetic dysfunction, at a presymptomatic stage. Conclusion: Our results provide mechanistic insight into the beneficial effects of antioxidants and enhance the rationale for translation into clinical trials for X-adrenoleukodystrophy. Antioxid. Redox Signal. 15, 2095–2107.
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Assessing yield losses caused by the harvester ant Messor barbarus (L.) in winter cereals

  • Baraibar Padró, Bàrbara
  • Ledesma, Raquel
  • Royo-Esnal, Aritz
  • Westerman, Paula Renate
Harvester ants from the species Messor barbarus (L.) are important seed predators in semi-arid cereal fields of NE Spain, and can contribute substantially to weed control. However, occasionally they harvest newly sown crop seeds at sowing in autumn, or ripe cereal grains close to harvest in summer, causing yield losses. A preliminary study was conducted in 34 commercial winter cereal fields to measure yield loss, and to identify factors that influence it. The area affected by ants was measured ten days prior to the anticipated harvest date. Ant colony size, nest density, crop height, weed densities and temperatures at sowing were assessed. At sowing, harvester ants did not cause yield losses (0.2% of potential yield on average). At harvest, yield losses were generally low as well (0.6%) although occasionally higher losses were recorded (max. 9.2%). Yield losses significantly increased with increasing nest density, nest size and with number of years of no-till. The results of this study show that in 2009 yield losses caused by M. barbarus were insignificant and more than offset by the benefits provided by the destruction of weed seeds.
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Mould growth and mycotoxin production as affected by Equisetum arvense and Stevia rebaudiana extracts

  • García, Daiana
  • García Cela, Esther
  • Ramos Girona, Antonio J.
  • Sanchís Almenar, Vicente
  • Marín Sillué, Sònia
Cereals are very important for human and animal diet. However, agricultural products can be contaminated by moulds and their mycotoxins. On the other hand, natural plant products with antimicrobial properties could be a possibility to control mycotoxigenic fungi in foods and feeds. In this study, Equisetum arvense and Stevia rebaudiana extracts were tested for their efficacy against a range of mycotoxigenic fungi. Maize agar medium (MAM 2%) was used for this study and E. arvense and S. rebaudiana extracts were added at different concentrations (1–3%) under different water activity (aw) levels (0.85–0.95). Six mycotoxigenic moulds were inoculated and incubated at different temperatures (15–30 °C) during 21 days. In general, no growth was observed with E. arvense extract at 3% in all studied conditions for all isolates. However, with S. rebaudiana extract at 2–3%, growth was not significantly decreased (p < 0.05) in most of the cases. Finally, in terms of toxin production, results were not conclusive. The use of E. arvense extracts as antifungals and antimycotoxigenics and their application should be further explored.
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