National Institute of Agronomic Research

Tunis, Tunisia

National Institute of Agronomic Research

Tunis, Tunisia
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Ghrab M.,University of Sfax | Chelli-Chaabouni A.,National Institute of Agronomic Research | Ben Mimoun M.,National Agronomic Institute of Tunisia
Acta Horticulturae | Year: 2016

In Tunisia, the usually used rootstock for pistachio is Pistacia vera. However, some wild pistachio species as P. atlantica and P. terebinthus spread naturally within Tunisia. They seem to be well adapted to the arid zone conditions where pistachio is planted. An experiment was carried out at the experimental station Taous (34°44'26"N, 10°45'37"E) in central Tunisia to study the scion-rootstock combinations of pistachio with two cultivars 'Mateur' and 'Kerman' grafted on P. vera and P. atlantica. Vegetative growth and physiological parameters were monitored for the four scion-rootstock combinations. Results showed that trees grafted on P. atlantica were more vigorous for both cultivars. Leaf chlorophyll and soluble sugar contents showed significant differences among scion-rootstock combinations. Pistacia atlantica induced higher leaf organic compounds (chlorophyll and soluble sugar) for both pistachio cultivars implying that it is a more interesting rootstock under Tunisian arid conditions characterized by high water scarcity and evaporative demand.


PubMed | University Hospital Galway, Galway Clinic, National Institute of Agronomic Research and NAMSA
Type: Comparative Study | Journal: Vascular | Year: 2016

The multilayer flow modulator (MFM; Cardiatis, Isnes, Belgium) is a self-expandable mesh of braided cobalt alloy wires, used for treatment of aortic and peripheral aneurysms. To further improve our understanding of this novel technology, the endothelialization kinetics of the MFM was investigated and compared with those of two marketed single-layer stents. Five porcine animal models were used in which a total of 19 stents were implanted in the iliac and carotid arteries between one and five weeks before sacrifice. All 19 stents were successfully delivered. For all devices, nonsignificant signs of inflammation or thrombosis were noted, and there was no evidence of local intolerance. The MFM developed a thin layer of endothelial cells earlier and was associated with less neointimal development than the two single-layer stents. A differing phenomenon of integration was also revealed and hypothesized as endothelialization from adhesion of circulating endothelial progenitor cells, as well as adhesion from the arterial wall, and also by the differences in trauma exposed to the arterial wall.


De Oliveira S.,Molecular Medicine Institute | De Oliveira S.,University of Lisbon | De Oliveira S.,University of Murcia | De Oliveira S.,Biomedical Research Institute of Murcia | And 5 more authors.
Journal of Immunology | Year: 2015

DUOX1-derived hydrogen peroxide (H2O2) and CXCL8 are two key neutrophil chemoattractants. H2O2 is critical at the early phase, whereas CXCL8 plays a key role in the late phases of recruitment, but the crosstalks between the two phases in vivo remain unknown. In this study using zebrafish, we report that H2O2 also contributes to neutrophil recruitment to injuries at the late phase as it induces Cxcl8 expression in vivo through a JNK/c-JUN/AP-1 signaling pathway. However, Erk and NF-κB signaling were not involved in this crosstalk. Strikingly, H2O2 also promotes cxcl8 expression through modulation of histone 3 lysine 4 trimethylation, histone 3 lysine 9 acetylation, and histone 3 lysine 9 trimethylation levels at its promoter. These results explain how early H2O2 signal regulates neutrophil recruitment at all phases, directly via Lyn oxidation or indirectly by modulating cxcl8 gene expression, via the activation of redox-sensitive signaling pathways, and further point out H2O2/DUOX1 as a key drug target for anti-inflammatory therapies. Copyright © 2015 by The American Association of Immunologists, Inc.


Peyron M.-A.,National Institute of Agronomic Research | Peyron M.-A.,University of Auvergne | Woda A.,University of Auvergne
Current Opinion in Food Science | Year: 2016

Developing masticatory apparatus, chewing robots or an artificial mouth is an old but ever more important goal in food science, nutrition or dental research fields, as reflected by the number of existing digital or biomechanical systems. Whatever the objective of the approach, basic knowledge of the physiology of mastication, adaptation and neurophysiological control is absolutely needed before conceiving an apparatus. Obviously, the final step in the development of a mastication simulator is its validation before performing food or food bolus characterization. This validation step is imperative to avoid biased interpretation and can be performed through in vivo-in vitro comparison of particle size distributions in food boluses obtained after normal mastication. This kind of validated machine offers the chance to produce boluses for other related uses such as nutrient bioaccessibility or digestion studies, for example. Such an apparatus can also be employed to simulate different dental states or ageing conditions. © 2016 Elsevier Ltd.


Gatineau E.,National Institute of Agronomic Research | Gatineau E.,Clermont 1 University | Savary-Auzeloux I.,National Institute of Agronomic Research | Savary-Auzeloux I.,Clermont 1 University | And 8 more authors.
Journal of Nutrition | Year: 2015

Background: Today, high chronic intake of added sugars is frequent, which leads to inflammation, oxidative stress, and insulin resistance. These 3 factors could reduce meal-induced stimulation of muscle protein synthesis and thus aggravate the age-related loss of muscle mass (sarcopenia). Objectives: Our aims were to determine if added sugars could accelerate sarcopenia and to assess the capacity of antioxidants and anti-inflammatory agents to prevent this. Methods: For 5 mo, 16-mo-old male rats were starch fed (13% sucrose and 49% wheat starch diet) or sucrose fed (62% sucrose and 0% wheat starch diet) with or without rutin (5 g/kg diet), vitamin E (4 times), vitamin A (2 times), vitamin D (5 times), selenium (10 times), and zinc (+44%) (R) supplementation. We measured the evolution of body composition and inflammation, plasma insulin-like growth factor 1 (IGF-I) concentration and total antioxidant status, insulin sensitivity (oral-glucose-tolerance test), muscle weight, superoxide dismutase activity, glutathione concentration, and in vivo protein synthesis rates. Results: Sucrose-fed rats lost significantly more lean body mass (-8.1% vs. -5.4%, respectively) and retained more fat mass (+0.2% vs. -33%, respectively) than starch-fed rats. Final muscle mass was 11% higher in starch-fed rats than in sucrose-fed rats. Sucrose had little effect on inflammation, oxidative stress, and plasma IGF-I concentration but reduced the insulin sensitivity index (divided by 2). Meal-induced stimulation of muscle protein synthesis was significantly lower in sucrose-fed rats (+7.3%) than in starch-fed rats (+22%). R supplementation slightly but significantly reduced oxidative stress and increasedmuscle protein concentration (+4%) but did not restore postprandial stimulation of muscle protein synthesis. Conclusions: High chronic sucrose intake accelerates sarcopenia in older male rats through an alteration of postprandial stimulation of muscle protein synthesis. This effect could be explained by a decrease of insulin sensitivity rather than by changes in plasma IGF-I, inflammation, and/or oxidative stress. © 2015 American Society for Nutrition.


Koubala B.B.,University of Maroua | Kansci G.,University of Yaounde I | Garnier C.,National Institute of Agronomic Research | Thibault J.-F.,National Institute of Agronomic Research | Ralet M.-C.,National Institute of Agronomic Research
Food and Bioprocess Technology | Year: 2013

The preparation of fibres from mango and ambarella peels can offer a way to upgrade by-products. Comparatively to lime, ambarella and mango fibres were prepared from their corresponding peels using ethanolic treatment (85% at 70 °C/5 min). The peels were characterised for their dry matter content, pH and apparent viscosity. The soluble dietary fibre (SDF) and insoluble dietary fibre (IDF) contents of the samples were determined. Hydration capacity of these fibres was evaluated. Results showed that the ethanolic treatment of the peels (85% at 70 °C/5 min) had significant (p < 0.05) effects on the contents of neutral sugars and uronic acid (from 105 to even 203 mg/g in case of mango fibre). For ambarella fibres, the proportion of IDF (51%) was highest and that of SDF (34%) was lowest. Mango and lime fibres exhibited similar values of IDF (40-43%) and SDF (50-57%). Mango peel fibres had higher hydration capacities than ambarella and lime fibres. The best dietary fibres content and the high hydration capacities of mango peel fibres favour their exploitation in dietary fibre-rich foods preparation. © 2011 Springer Science+Business Media, LLC.


Alvarez-Vasquez F.J.,National Institute of Agronomic Research | Freyre-Gonzalez J.A.,National Autonomous University of Mexico | Balderas-Martinez Y.I.,National Autonomous University of Mexico | Delgado-Carrillo M.I.,University of British Columbia | Collado-Vides J.,National Autonomous University of Mexico
Molecular BioSystems | Year: 2015

Transcription factors (TFs) modulate gene expression as a consequence of internal or exogenous changes in cell signaling. TFs can bind to DNA either with their effector bound (holo conformation), or as free proteins (apo conformation). With the aim of contributing to the understanding of the evolutionary fitness and organizational principles behind the different TF conformations, we inquire into the origins of these conformational differences by analyzing these two TF conformations from the perspective of Savageau's demand theory. For the control of a gene whose function is in high demand, we found that evolutionary constraints are responsible for activator TFs binding to DNA mainly in holo conformation whereas apo activation is under-represented. The mathematically controlled comparison of the apo and holo conformations reveals formal and evolutionary arguments in favor of this TF control asymmetry, which suggests that evolution favors holo activation under environmental conditions commonly found by E. coli in the human digestive tract. Specifically, the sensibility analysis performed for the holo conformation, in the positive mode of regulation, shows that the wild-type is more robust for situations where realizable changes in the model's parameters favored a better performance under non-stressful environmental conditions commonly found by E. coli in the human digestive tract. By contrast, the positive apo conformation is better adapted to adverse situations. On the other hand, the sensibility analysis performed for the negative mode of regulation showing none of the TF active conformations presents an advantage. © The Royal Society of Chemistry 2015.


Zardo D.M.,State University of Ponta Grossa | Silva K.M.,State University of Ponta Grossa | Guyot S.,National Institute of Agronomic Research | Nogueira A.,State University of Ponta Grossa
International Journal of Food Sciences and Nutrition | Year: 2013

This study evaluated the phenols of the Gala, Fuji and Golden Delicious varieties, which make up 95% of Brazilian production. The phenolic profiles (whole fruit) were determined by high pressure liquid chromatography, total phenols were determined using the Folin-Ciocalteau method and antioxidant capacity by the FRAP method (whole fruit, skin, pulp and centre). The Golden Delicious had the highest phenol content (408 mg/fruit) compared to Fuji (194 mg/fruit) and Gala (162 mg/fruit), and the antioxidant capacity of the Golden Delicious was 2.5 and 3.6 times higher than that found in the Fuji and Gala, respectively. The phenolic profile for the three varieties showed 5-caffeoylquinic acid, ( - )-epicatechin, procyanidin B2 and phloridzin as major components with procyanidins as the predominant class and quercetin as the minority. The consumption of apple pulp may provide 48-78% of the antioxidant capacity; however, if the peel is ingested, it may increase to 79-89%. The type of apple variety and the parts ingested are factors that must be taken into consideration in consumption. © 2013 Informa UK, Ltd.


PubMed | National Institute of Agronomic Research, Ehime University, Carolina AquaGyn, North Carolina State University and Hokkaido University
Type: | Journal: General and comparative endocrinology | Year: 2015

Fish egg yolk is largely derived from vitellogenins, which are synthesized in the liver, taken up from the maternal circulation by growing oocytes via receptor-mediated endocytosis and enzymatically processed into yolk proteins that are stored in the ooplasm. Lipid droplets are another major component of fish egg yolk, and these are mainly composed of neutral lipids that may originate from maternal plasma lipoproteins. This review aims to briefly summarize our current understanding of the molecular mechanisms underlying yolk formation in fishes. A hypothetical model of oocyte growth is proposed based on recent advances in our knowledge of fish yolk formation.


PubMed | National Institute of Agronomic Research
Type: Journal Article | Journal: Molecular bioSystems | Year: 2015

Transcription factors (TFs) modulate gene expression as a consequence of internal or exogenous changes in cell signaling. TFs can bind to DNA either with their effector bound (holo conformation), or as free proteins (apo conformation). With the aim of contributing to the understanding of the evolutionary fitness and organizational principles behind the different TF conformations, we inquire into the origins of these conformational differences by analyzing these two TF conformations from the perspective of Savageaus demand theory. For the control of a gene whose function is in high demand, we found that evolutionary constraints are responsible for activator TFs binding to DNA mainly in holo conformation whereas apo activation is under-represented. The mathematically controlled comparison of the apo and holo conformations reveals formal and evolutionary arguments in favor of this TF control asymmetry, which suggests that evolution favors holo activation under environmental conditions commonly found by E. coli in the human digestive tract. Specifically, the sensibility analysis performed for the holo conformation, in the positive mode of regulation, shows that the wild-type is more robust for situations where realizable changes in the models parameters favored a better performance under non-stressful environmental conditions commonly found by E. coli in the human digestive tract. By contrast, the positive apo conformation is better adapted to adverse situations. On the other hand, the sensibility analysis performed for the negative mode of regulation showing none of the TF active conformations presents an advantage.

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