886 resultados para nutrition and dietetics


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[EN] Since paralarval rearing is still the main bottleneck for the development of octopus culture, the aim of the present study was to obtain some information on the feeding strategy and nutritional requirements during paralarval stage. For that purpose just hatched out octopus paralarvae were fed with live preys in three different combinations, trying to match their natural food: Enriched Artemia metanauplii, Grapsus grapsus zoeas supplemented with enriched Artemia, and Plagusia depressa zoeas supplemented with enriched Artemia. Paralarval treatments were carried out during 28 days in triplicates; fibre glass 120 l tanks in flow through system were used. Growth, in terms of dry body weight, mantle length and width, was determined each seven days. A histological study of the paralarval development was carried out. Biochemical composition of preys and paralarvae were determined. Growth was significantly better in paralarvae fed with zoeas and Artemia than in those fed only with Artemia, from day 8 after hatching. Besides a clear effect on the digestive gland histology morphology was observed.

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[ES] Main deformities such as lordosis, opercular deformities and upper/lower jaws shortening are considered as quality descriptors in commercial marine fish fry production and seem to be related with larval culture conditions in early larval stages. The aim of this work was to obtain information about the contribution of the diet and rearing system to the apparition of these abnormalities in gilthead sea bream (Sparus aurata) larvae in semi-industrial scale facilities. For that purpose, two different larval rearing systems semi-intensive and intensive were compared; besides, two different rotifer enrichments, DHA Protein Selco, (Inve Aquaculture, Dendermonde, Belgium) (R1) and Red Pepper Paste, (Bernaqua bvba, Turnhout, Belgium) were tested in the intensive system. Biochemical composition of larvae, preys and commercial products was analysed. At 50 days post hatching six hundred fish per treatment were individually studied under stereoscope and deformity frequency recorded. Besides at 95 days post hatching fry were soft X ray monitored. Both rotifer enrichment and rearing system affected survival, growth and deformity frequency. Rearing system did not affect total larvae fatty acid content except at 20 dah, where DHA were significantly higher and EPA significantly lower in Semi-intensive system. A significantly lower percentage of deformity rates together with better survival and growth were obtained in the semi-intensive system. In dietary treatment, rotifer enrichment significantly affected larval survival. R1 rotifers enrichment significantly (P<0.05) improved survival when compared to fed R2 larvae. The content of DPA was significantly (P<0.05) higher in R2 fed larvae reflecting the R2 rotifers content of this fatty acid. The level of this FA tended to decrease in concordance with the rotifers replacement by artemia in the diet. The effects n-3-HUFA and DPA (22:5n-6) over larval survival and skeletal deformities development is discussed.

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Copper and Zn are essential micronutrients for plants, animals, and humans; however, they may also be pollutants if they occur at high concentrations in soil. Therefore, knowledge of Cu and Zn cycling in soils is required both for guaranteeing proper nutrition and to control possible risks arising from pollution.rnThe overall objective of my study was to test if Cu and Zn stable isotope ratios can be used to investigate into the biogeochemistry, source and transport of these metals in soils. The use of stable isotope ratios might be especially suitable to trace long-term processes occurring during soil genesis and transport of pollutants through the soil. In detail, I aimed to answer the questions, whether (1) Cu stable isotopes are fractionated during complexation with humic acid, (2) 65Cu values can be a tracer for soil genetic processes in redoximorphic soils (3) 65Cu values can help to understand soil genetic processes under oxic weathering conditions, and (4) 65Cu and 66Zn values can act as tracers of sources and transport of Cu and Zn in polluted soils.rnTo answer these questions, I ran adsorption experiments at different pH values in the laboratory and modelled Cu adsorption to humic acid. Furthermore, eight soils were sampled representing different redox and weathering regimes of which two were influenced by stagnic water, two by groundwater, two by oxic weathering (Cambisols), and two by podzolation. In all horizons of these soils, I determined selected basic soil properties, partitioned Cu into seven operationally defined fractions and determined Cu concentrations and Cu isotope ratios (65Cu values). Finally, three additional soils were sampled along a deposition gradient at different distances to a Cu smelter in Slovakia and analyzed together with bedrock and waste material from the smelter for selected basic soil properties, Cu and Zn concentrations and 65Cu and 66Zn values.rnMy results demonstrated that (1) Copper was fractionated during adsorption on humic acid resulting in an isotope fractionation between the immobilized humic acid and the solution (65CuIHA-solution) of 0.26 ± 0.11‰ (2SD) and that the extent of fractionation was independent of pH and involved functional groups of the humic acid. (2) Soil genesis and plant cycling causes measurable Cu isotope fractionation in hydromorphic soils. The results suggested that an increasing number of redox cycles depleted 63Cu with increasing depth resulting in heavier 65Cu values. (3) Organic horizons usually had isotopically lighter Cu than mineral soils presumably because of the preferred uptake and recycling of 63Cu by plants. (4) In a strongly developed Podzol, eluviation zones had lighter and illuviation zones heavier 65Cu values because of the higher stability of organo-65Cu complexes compared to organo-63Cu complexes. In the Cambisols and a little developed Podzol, oxic weathering caused increasingly lighter 65Cu values with increasing depth, resulting in the opposite depth trend as in redoximorphic soils, because of the preferential vertical transport of 63Cu. (5) The 66Zn values were fractionated during the smelting process and isotopically light Zn was emitted allowing source identification of Zn pollution while 65Cu values were unaffected by the smelting and Cu emissions isotopically indistinguishable from soil. The 65Cu values in polluted soils became lighter down to a depth of 0.4 m indicating isotope fractionation during transport and a transport depth of 0.4 m in 60 years. 66Zn values had an opposite depth trend becoming heavier with depth because of fractionation by plant cycling, speciation changes, and mixing of native and smelter-derived Zn. rnCopper showed measurable isotope fractionation of approximately 1‰ in unpolluted soils, allowing to draw conclusions on plant cycling, transport, and redox processes occurring during soil genesis and 65Cu and 66Zn values in contaminated soils allow for conclusions on sources (in my study only possible for Zn), biogeochemical behavior, and depth of dislocation of Cu and Zn pollution in soil. I conclude that stable Cu and Zn isotope ratios are a suitable novel tool to trace long-term processes in soils which are difficult to assess otherwise.rn

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The growing substrate of the putting greens is considered a key factor for a healthy turf ecosystem. Actually detailed study on the effects of growth promoting bacteria and biostimulants on a professional sport turf are very limited. This thesis aimed to study the effectiveness of different microorganisms and biostimulants in order to improve the knowledge relative to the relationship between the beneficial microflora and root apparatus of sport turfs. The research project was divided in three principal steps: Initially, commercial products based on biostimulants and microorganisms were tested on a Lolium perenne L. essence grown in a controlled-environment. The principal evaluations were the study of the habitus of plants, biomass production and length of leaves and roots. Were studied the capacity of colonization of microorganisms within root tissues and rhizosphere. In the second step were developed two different biostimulant solutions based on effective microorganisms, mycorrhizae and humic acids. This test was conducted both on an Agrostis stolonifera putting green (Modena Golf & Country Club) in a semi-field condition and within a growth chamber on a Lolium perenne L. essence. Fungicide and chemicals applications were suspended in order to assess the effectiveness of the inoculants for nutrition and control of pests. In the last step, different microorganism mixes and biostimulants were tested on an experimental putting green in the Turf Research Center (TRC) (Virginia Tech, United States) in a real managing situation. The effects of different treatments were studied maintaining all chemicals and mechanicals managements scheduled during a sport season. Both growth-chamber and field results confirmed the capacity of microorganisms based biostimulants to promote the physiologic conditions of the plants, improve the growth of the roots and enhance the aesthetic performance of the turf. Molecular analysis confirmed the capacity of microorganisms to colonize the root tissues.

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The antiinflammatory agent curcumin (diferuloylmethane) has a potential to mitigate cancer therapy-induced mucositis. We assessed the in vitro extent of its bactericidal activity and determined the kinetics of its antiinflammatory effect on pharyngeal cells. Bactericidal activity was assessed using the LIVE/DEAD® Kit after 4 h of exposure to curcumin (50-200 μM) in 18 oropharyngeal species commonly associated with bacteremia in febrile neutropenia. Moraxella catarrhalis or its outer membrane vesicles were used to determine the inhibitory effect of curcumin on bacteria-induced proinflammatory activity as determined by cytokine release into the supernatant of Detroit 562 pharyngeal cells using the Luminex® xMAP® technology. Curcumin exerted a concentration-dependent bactericidal effect on all 18 species tested. After 4 h at 200 μM, 12 species tested were completely killed. Preincubation of Detroit cells with 200 μM curcumin for 5 to 60 min resulted in complete suppression of the release of tumor necrosis factor-α, interleukin (IL)-6, IL-8, monocyte chemoattractant protein 1, granulocyte macrophage-colony stimulating factor, and vascular endothelial growth factor. Fibroblast growth factor-2 and interferon-γ were not affected. Repetitive exposure to curcumin resulted in repetitive suppression of cytokine/chemokine expression lasting from 4 to 6 h. Through reduction of oral microbial density as well as suppression of inflammation cascades curcumin may prevent cancer therapy-induced oral mucositis, e.g., when applied as multiple daily mouth washes.

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INTRODUCTION The ATP-binding cassette (ABC) transporter A1 (ABCA1) and ABCG1 are highly expressed in the placenta in various compartments, including the villous syncytiotrophoblast (V-STB) and foetal endothelial cells. Among other not yet characterized functions, they play a role in the foeto-maternal transport of cholesterol and other lipophilic molecules. In humans, preliminary data suggest expressional changes of ABCA1 and ABCG1 in pathologic gestation, particularly under hypoxic conditions, but a systematic expression analysis in common human pregnancy diseases has never been performed. OBJECTIVES The aim of the present study was to characterize ABCA1 and ABCG1 expression in a large series of pathologic placentas, in particular from preeclampsia (PE) and intrauterine growth restriction (IUGR) which are associated with placental hypoxia. METHODS Placentas from 152 pathological pregnancies, including PE and/or HELLP (n=24) and IUGR (n=21), and 20 normal control placentas were assessed for their ABCA1 and ABCG1 mRNA and protein expression with quantitative RT-PCR and semi-quantitative immunohistochemical analysis, respectively. RESULTS ABCA1 protein expression in the V-STB was significantly less extensive in PE compared with normal controls (<10% of V-STB stained for ABCA1 in 58% PE placentas vs. 25% controls; p=0.035). Conversely, it was significantly more wide-spread in IUGR (>75% of V-STB stained in 57% IUGR placentas vs. 15% controls; p=0.009). Moreover, there was an insignificant trend for increased ABCA1 expression in fetal endothelial cells of stem villi in PE (p=0.0588). ABCA1 staining levels in V-STB were significantly associated with placental histopathological features related with hypoxia: they were decreased in placentas exhibiting syncytial knotting (p=0.033) and decidual vasculopathy (p=0.0437) and increased in low weight placentas (p=0.015). The significant and specific alterations in ABCA1 protein expression found at a specific cellular level were not paralleled by changes in ABCA1 mRNA abundance of total placental tissue. ABCG1 staining was universally extensive in the V-STB of normal placentas, always affecting more than 90% of V-STB surface. In comparison, ABCG1 staining of the V-STB was generally often reduced in pregnancy diseases. In particular, less than 90% of V-STB exhibited ABCG1 staining in 26% of PE placentas (p=0.022) and 35% of IUGR placentas (p=0.003). Similarly to ABCA1, ABCG1 mRNA expression in total placental tissue was not significantly different between controls and PE or IUGR. CONCLUSION ABCA1 and ABCG1 proteins are differentially expressed, with either down- or up-regulation, in the V-STB of placentas exhibiting features of chronic hypoxia, such as in PE and IUGR. This suggests that other factors in addition to hypoxia regulate the expression of placental lipid transporters. The specific changes on a cellular level were masked when only total tissue mRNA was analysed underlining the importance of cell specific expression analysis. The potential effects of decreased placental ABCA1 and ABCG1 expression on foetal nutrition and development remain to be elucidated.

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As part of the ESA-funded MELiSSA program, the suitability, the growth and the development of four bread wheat cultivars were investigated in hydroponic culture with the aim to incorporate such a cultivation system in an Environmental Control and Life Support System (ECLSS). Wheat plants can fulfill three major functions in space: (a) fixation of CO2 and production of O2, (b) production of grains for human nutrition and (c) production of cleaned water after condensation of the water vapor released from the plants by transpiration. Four spring wheat cultivars (Aletsch, Fiorina, Greina and CH Rubli) were grown hydroponically and compared with respect to growth and grain maturation properties. The height of the plants, the culture duration from germination to harvest, the quantity of water used, the number of fertile and non-fertile tillers as well as the quantity and quality of the grains harvested were considered. Mature grains could be harvested after around 160 days depending on the varieties. It became evident that the nutrient supply is crucial in this context and strongly affects leaf senescence and grain maturation. After a first experiment, the culture conditions were improved for the second experiment (stepwise decrease of EC after flowering, pH adjusted twice a week, less plants per m2) leading to a more favorable harvest (higher grain yield and harvest index). Considerably less green tillers without mature grains were present at harvest time in experiment 2 than in experiment 1. The harvest index for dry matter (including roots) ranged from 0.13 to 0.35 in experiment 1 and from 0.23 to 0.41 in experiment 2 with modified culture conditions. The thousand-grain weight for the four varieties ranged from 30.4 to 36.7 g in experiment 1 and from 33.2 to 39.1 g in experiment 2, while market samples were in the range of 39.4–46.9 g. Calcium levels in grains of the hydroponically grown wheat were similar to those from field-grown wheat, while potassium, magnesium, phosphorus, iron, zinc, copper, manganese and nickel levels tended to be higher in the grains of experimental plants. It remains a challenge for future experiments to further adapt the nutrient supply in order to improve senescence of vegetative plant parts, harvest index and the composition of bread wheat grains.

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Abstract Many plants form associations with arbuscular mycorrhizal fungi (AMF) because they profit from improved phosphorus nutrition and from protection against pathogens. Whereas mycorrhiza-induced pathogen protection is well understood in agricultural plant species, it is rarely studied in wild plants. As many pathogens infest plants in the first days after germination, mycorrhiza-induced pathogen protection may be especially important in the first few weeks of plant establishment. Here, we investigated interacting effects of {AMF} and the seedling pathogen Pythium ultimum on the performance of six- to seven-week-old seedlings of six wild plant species of the family Asteraceae in a full factorial experiment. Plant species differed in their response to AMF, the pathogen and their interactions. {AMF} increased and the pathogen decreased plant biomass in one and three species, respectively. Two plant species were negatively affected by {AMF} in the absence, but positively or not affected in the presence of the pathogen, indicating protection by AMF. This mycorrhiza-induced pathogen protection is especially surprising as we could not detect mycorrhizal structure in the roots of any of the plants. Our results show that even seedlings without established intraradical hyphal network can profit from AMF, both in terms of growth promotion in the absence of a pathogen and pathogen protection. The function of {AMF} is highly species-specific, but tends to be similar for more closely related plant species, suggesting a phylogenetic component of mycorrhizal function. Further studies should test a wider range of plant species, as our study was restricted to one plant family, and investigate whether plants profit from early mycorrhizal benefits in the long term.

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INTRODUCTION Supplementation with beta-alanine may have positive effects on severe-intensity, intermittent, and isometric strength-endurance performance. These could be advantageous for competitive alpine skiers, whose races last 45 to 150 s, require metabolic power above the aerobic maximum, and involve isometric muscle work. Further, beta-alanine supplementation affects the muscle force-frequency relationship, which could influence explosiveness. We explored the effects of beta-alanine on explosive jump performance, severe exercise energy metabolism, and severe-intensity ski-like performance. METHODS Nine male elite alpine skiers consumed 4.8 g/d beta-alanine or placebo for 5 weeks in a double-blind fashion. Before and after, they performed countermovement jumps (CMJ), a 90-s cycling bout at 110% VO2max (CLT), and a maximal 90-s box jump test (BJ90). RESULTS Beta-alanine improved maximal (+7 ± 3%, d = 0.9) and mean CMJ power (+7 ± 2%, d = 0.7), tended to reduce oxygen deficit (-3 ± 8%, p = .06) and lactate accumulation (-12 ± 31%) and enhance aerobic energy contribution (+1.3 ± 2.9%, p = .07) in the CLT, and improved performance in the last third of BJ90 (+7 ± 4%, p = .02). These effects were not observed with placebo. CONCLUSIONS Beta-alanine supplementation improved explosive and repeated jump performance in elite alpine skiers. Enhanced muscle contractility could possibly explain improved explosive and repeated jump performance. Increased aerobic energy production could possibly help explain repeated jump performance as well.

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Food security is the main concern in Africa as the production and productivity of crops are under continuous threat. Indigenous crops also known as orphan- or as underutilized- crops provide key contributions to food security under the present scenario of increasing world population and changing climate. Hence, these crops which belong to the major categories of cereals, legumes, fruits and root crops play a key role in the livelihood of the resource-poor farmers and consumers since they perform better than the major world crops under extreme soil and climate conditions prevalent in the continent. These indigenous crops have the major advantage that they fit well into the general socio-economic and ecological context of the region. However, despite their huge importance, African crops have generally received little attention by the global scientific community. With the current production systems, only a fraction of yield potential was achieved for most of these crops. In order to devise strategies towards boosting crop productivity in Africa, the current production constraints should be investigated and properly addressed. Key traits known to increase productivity and/or improve nutrition and diverse conventional and modern crop improvement techniques need to be implemented. Commitments in the value-chain from the research, production, marketing to distribution of improved seeds are required by relevant national and international institutions as well as African governments to promote food security in a sustainable manner. The review also presents major achievements and suggestions for stakeholders interested in African agriculture.