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Extracellular vesicles from olive co-products: Isolation, characterization and antioxidant activity
No full textExtracellular vesicles (EVs) are nanoscopic membranous structures which are involved
in intercellular communication between cells and could have interesting antioxidant/antiinflammatory
properties. Recent works highlighted the existence of EVs secreted by
plant cells.
The objective of our study, is to characterize the main physico-chemical properties of
EVs isolated from two types of olive coproducts (wastewater and pomace) and compare
the properties of EVs to the one of the initial co-products they were extracted from.
Isolation was carried out using successive centrifugations using as raw materials: one
wastewater and two pomaces (one mono varietal, one plurivarietal). Pomaces were
either used without pretreatment or after lyophilization. In total, EVs were isolated from
four types of raw material: wastewaters (WW), fresh mono varietal pomace (MP), fresh
plurivarietal pomace (PM), lyophilized plurivarietal pomace (LP). The main physical
characterizations were size and charge using Dynamic Light Scattering (DLS) and Zeta
Potential (ZP). The chemical characterization included phenolic compounds
characterization using HPLC and lipid classes with TLC. Furthermore, test of their
antioxidant activity was conducted using DPPH and CAT (Conjugated autoxidizable
triene) assay. DPPH gave access to reducing power in homogeneous media and gave
an insight into intrinsic reducing power of the constituent EVs molecules. CAT assay
gave access to antioxidant activity in dispersed (emulsion based) media and preserve
the bioassembly effect of EVs.
EVs isolated from the four co-products (WW, MP, PP, LP) presented distinct physicochemical
properties. EVs diameter ranged 20-300nm according to the type of coproduct.
Most EVs presented on a [2-7] pH range an evolution of charge from positive
values at acidic pH to negative ones at basic pH, with an isoelectric point ranging
between [2-3]. EVs isolated from wastewaters were the most concentrated with phenolic
compounds (0.5mM eq HT) and contained more neutral lipids than EVs isolated from
pomace. However similar polar lipids classes (PA>PC>MGDG>PE) were found in all
fractions. Wastewaters EVs was the fraction with the highest antioxidant activity in both
antioxidant activity tests: DPPH and CAT.
Physical characteristics (size, charge) of isolated fractions are in agreement with values
reported for vesicles in literature. EVs isolated from wastewaters were more
concentrated in polar lipids (membranous lipids) and phenolic compounds. Furthermore
DPPH and CAT assay showed an antioxidant effect for putative EVs, indicating
promising potential of these assemblies
Phenomenal: An automatic open source library for 3D shoot architecture reconstruction and analysis for image-based plant phenotyping
No full textIn the era of high-throughput visual plant phenotyping, it is crucial to design fully automated and flexible workflows able to derive quantitative traits from plant images. Over the last years, several software supports the extraction of architectural features of shoot systems. Yet currently no end-to-end systems are able to extract both 3D shoot topology and geometry of plants automatically from images on large datasets and a large range of species. In particular, these software essentially deal with dicotyledons, whose architecture is comparatively easier to analyze than monocotyledons. To tackle these challenges, we designed the Phenomenal software featured with: (i) a completely automatic workflow system including data import, reconstruction of 3D plant architecture for a range of species and quantitative measurements on the reconstructed plants; (ii) an open source library for the development and comparison of new algorithms to perform 3D shoot reconstruction and (iii) an integration framework to couple workflow outputs with existing models towards model-assisted phenotyping. Phenomenal analyzes a large variety of data sets and species from images of high-throughput phenotyping platform experiments to published data obtained in different conditions and provided in a different format. Phenomenal has been validated both on manual measurements and synthetic data simulated by 3D models. It has been also tested on other published datasets to reproduce a published semi-automatic reconstruction workflow in an automatic way. Phenomenal is available as an open-source software on a public repository
Inflammation: friend or foe of bovine reproduction?
No full textInflammation is not only the first line of defense of the organism but is also required in many reproductive processes such as ovulation, corpus luteum development, luteolysis, uterine clearance after insemination and post partum. Nevertheless, if excessive or persistent, inflammation can switch from a positive mechanism to a deleterious process, impairing oocyte quality and embryo development. Not only uterine but also non genital inflammatory sites can depreciate reproductive performances, with a carry over effect of 2 to 4 months. Since the metabolic challenges of the peripartum transition period make difficult for the cow to control inflammation, dairy cows are frequently in a pro-inflammatory stage, suggesting that inflammation, rather than infection, is a limiting factor of fertility in modern dairy cows. Within the first week after calving, cows have to mount an intense inflammatory response to the bacterial invasion of the uterine cavity with the challenge of being able to switch it off in no more than 5-6 weeks. The absence of neutrophils on endometrial smear is associated with the highest success rate at insemination. Since a fine tuning - rather than an absence - of inflammation is required along the reproductive cycle, anti-inflammatory drugs do not allow any improvement of pregnancy rate, except in the specific case of embryo transfer. Appropriate management of the transition period (especially nutritional) and in a long term perspective, genetic selection contribute to improve the aptitude of cows to controls the intensity of inflammatory process
Peptidoglycan-dependent NF-κB activation in a small subset of brain octopaminergic neurons controls female oviposition
No full textWhen facing microbes, animals engage in behaviors that lower the impact of the infection. We previously demonstrated that internal sensing of bacterial peptidoglycan reduces Drosophila female oviposition via NF-kappaB pathway activation in some neurons (Kurz et al., 2017). Although we showed that the neuromodulator octopamine is implicated, the identity of the involved neurons, as well as the physiological mechanism blocking egg-laying, remained unknown. In this study, we identified few ventral nerve cord and brain octopaminergic neurons expressing an NF-kappaB pathway component. We functionally demonstrated that NF-kappaB pathway activation in the brain, but not in the ventral nerve cord octopaminergic neurons, triggers an egg-laying drop in response to infection. Furthermore, we demonstrated via calcium imaging that the activity of these neurons can be directly modulated by peptidoglycan and that these cells do not control other octopamine-dependent behaviors such as female receptivity. This study shows that by sensing peptidoglycan and hence activating NF-kappaB cascade, a couple of brain neurons modulate a specific octopamine-dependent behavior to adapt female physiology status to their infectious state
Effet de l’association du haricot mungo sur le rendement du mil dans le Bassin arachidier, Sénégal
No full textLa production agricole au Sénégal est limitée par la variabilité des précipitations, les sécheresses
persistantes et la faible fertilité des sols. Ces contraintes ont contribué à la baisse des rendements du
mil au Sénégal. Le haricot mungo, une légumineuse à graines à cycle court et relativement tolérante à
la sécheresse, est capable d'améliorer la fertilité du sol et d’augmenter la production agricole. Pour
étudier le potentiel du haricot mungo à augmenter le rendement du mil, des essais ont été menés
pendant la saison culturale de 2017 à Bambey (Diourbel). Les systèmes d’association (mil seul (T1),
haricot mungo seul (T2) et 23% (T3), 43% (T4), 47% (T5), 62% (T6), 125% (T7) et 164% (T8) de haricot
mungo en association avec le mil) ont été disposés en blocs complets randomisés et répliqués quatre
fois. Les données collectées comprennent les paramètres de rendement du mil et du haricot mungo et
le rendement total en grains, l'indice de végétation par différence normalisée (NDVI), le taux de
couverture du sol, et le land equivalent ratio (LER). L’association du mil avec le haricot mungo n'a pas
significativement augmenté la biomasse et le rendement en grains du mil par rapport au mil seul.
Cependant, le rendement en grains, le nombre de gousses et de graines, et la hauteur des plants de
haricot mungo ont été significativement plus élevés pour les traitements T7 et T8 par rapport aux autres
traitements. Le rendement total en grains était aussi significativement (P ≤ 0,05) plus élevé (jusqu'à
56%) en association. De même, l’association des cultures a entrainé des différences significatives pour
le LER et le taux de couverture du sol (62%) mais pas pour les valeurs de NDVI. Les résultats de cette
première année suggèrent que l'association avec le haricot mungo pourrait soutenir la production de mil
grâce à la diversification des systèmes agricoles.Agricultural production in Senegal is constrained by rainfall variability, persistent droughts, and low soil
fertility. These constraints have decreased pearl millet yield in Senegal. Mungbean, a short-duration and
relatively drought-tolerant grain legume, is capable of improving soil fertility and increasing crop
production. To investigate the potential of mungbean for increasing millet yield through intercropping,[br/]
field experiments were conducted during the 2017 growing season in Bambey (Senegal). Intercropping
treatments (sole millet (T1), sole mungbean (T2), and 23% (T3), 43% (T4), 47% (T5), 62% (T6), 125% (T7)
et 164% (T8) of mungbean in sole millet) were laid out in a randomized complete block design and
replicated four times. Studied parameters included millet and mungbean yield parameters and combined
yields, normalized difference vegetation index (NDVI), canopy cover, and land equivalent ratio (LER).
Intercropping (millet + mungbean) did not significantly increase millet biomass or grain yield compared
to millet alone. However, grain yield, number of pods and seeds, and plant height of mungbean plants
were significantly higher in T7 and T8 compared to other treatments. Combined yields were also
significantly (P ≤ 0.05) higher (up to 56%) under millet – mungbean intercropping. Similarly,
intercropping significantly (P ≤ 0.05) increased LER and canopy cover (62%) over millet alone but not
NDVI values. Results from this first-year suggest that intercropping with mungbean could sustain millet
production through diversification of agricultural systems
Valuing health surveillance as an information system: Interdisciplinary insights
No full textThe economic evaluation of health surveillance systems and of health information is a methodological challenge, as for information systems in general. Main present threads are considering cost-effectiveness solutions, minimizing costs for a given technically required output, or cost-benefit analysis, balancing costs with economic benefits of duly informed public interventions. The latter option, following a linear command-and-control perspective, implies considering a main causal link between information, decision, action, and health benefits. Yet, valuing information, taking into account its nature and multiple sources, the modalities of its processing cycle, from production to diffusion, decentralized use and gradual building of a shared information capital, constitutes a promising challenge. This work proposes an interdisciplinary insight on the value of health surveillance to get a renewed theoretical framework integrating information and informatics theory and information economics. The reflection is based on a typological approach of value, basically distinguishing between use and non-use values. Through this structured discussion, the main idea is to expand the boundaries of surveillance evaluation, to focus on changes and trends, on the dynamic and networked structure of information systems, on the contribution of diverse data, and on the added value of combining qualitative and quantitative information. Distancing itself from the command-and-control model, this reflection considers the behavioral fundaments of many health risks, as well as the decentralized, progressive and deliberative dimension of decision-making in risk management. The framework also draws on lessons learnt from recent applications within and outside of health sector, as in surveillance of antimicrobial resistance, inter-laboratory networks, the use of big data or web sources, the diffusion of technological products and large-scale financial risks. Finally, the paper poses the bases to think the challenge of a workable approach to economic evaluation of health surveillance through a better understanding of health information value. It aims to avoid over-simplifying the range of health information benefits across society while keeping evaluation within the boundaries of what may be ascribed to the assessed information system
DAIRYdb: a manually curated reference database for improved taxonomy annotation of 16S rRNA gene sequences from dairy products
No full textNew sequencing technologies allowed the development of methods such as metabarcoding. They use 16S rRNA, the ubiquitous gene of the bacteria domain, as a biomarker to study bacterial communities from samples of complex environments.
The bioinformatic pipelines used to handle this type of data are well known but the taxonomic assignment is still a critical point. Misannotations are caused by short size sequences and high identity between bacterial species. Indeed, current technologies only allow to sequence two hyper-variable regions among the nine which compose the 16S rRNA. The available generalist databases (Greengenes, SILVA) do not reach enough accuracy to assign to the species rank. It is needed to create a curated reference database dedicated to the studied environment.
Here we introduce the DAIRYdb, a manually curated database composed of full length 16S rRNA sequences from samples of dairy products and close environments (cheese, milk, teat surface, starter, whey). The DAIRYdb was constructed using the 16S rRNA sequences deposited in EMBL and NCBI. After bioinformatic treatments, automatic and manual curative steps, DAIRYdb is finally composed of 10290 complete 16S sequences. It shows a higher assignment accuracy compared to other databases, at all taxonomic ranks and with any assignment tool tested. Depending on the variable region used, up to 90% of the tested sequences are reassigned to the species level with DAIRYdb.
DAIRYdb significantly improves taxonomic assignment accuracy for dairy environmental microbiome studies. It is available on public a repository (https://forgemia.inra.fr/umrf/dairydb)
PPR Control in a Sahelian setting: What vaccination strategy for Mauritania?
No full textPeste des Petits Ruminants (PPR) is a viral disease affecting domestic and small wild ruminants. Endemic in large parts of the world, PPR causes severe damages to animal production and household economies. In 2015, FAO and OIE launched a global eradication program (GCSE) based on vaccination campaigns. The success of GCSE shall depend on the implementation of vaccination campaigns, accounting for husbandry practices, mobility and the periodicity of small ruminants' population renewal. In Mauritania, PPR outbreaks occur annually despite ongoing annual vaccination campaigns since 2008. Here, we developed a mathematical model to assess the impact of four vaccination strategies (including the GSCE one), the importance of their timing of implementation and the usefulness of individual animal identification on the reduction of PPR burden. The model was calibrated on data collected through ad-hoc surveys about demographic dynamics, disease impact, and national seroprevalence using Monte Carlo Markov Chain procedure. Numerical simulations were used to estimate the number of averted deaths over the next 12 years. The model results showed that the GSCE strategy prevented the largest number of deaths (9.2 million vs. 6.2 for random strategy) and provided one of the highest economic returns among all strategies (Benefit-Cost Ratio around 16 vs. 7 for random strategy). According to its current cost, identification would be a viable investment that could reduce the number of vaccine doses to distribute by 20-60%. Whilst the implementation of the identification system is crucial for PPR control, its success depends also on a coordinated approach at the regional level
Short Food Supply Chains and Their Contributions to Sustainability: Participants’ Views and Perceptions from 12 European Cases
No full textThe present food system faces major challenges in terms of sustainable development along social, economic and environmental dimensions. These challenges are often associated with industrialised production processes and longer and less transparent distribution chains. Thus, closer distribution systems through Short Food Supply Chains (SFSCs) may be considered as a sustainable alternative. This study explores the role of different types of SFSCs and their contribution to sustainability through participants’ (consumers, retailers and producers) views and perceptions. As part of the European H2020 project “Strength2Food” we conducted a cross-case analysis and examined 12 European SFSC cases from six countries: France, Hungary, Italy, Norway, Poland and the UK. We applied a mixed method approach including primary data collection, via in-depth interviews and customer surveys, as well as desk research. The findings suggest that, irrespective of the type of SFSC, a strong agreement among the participants were found on the contribution of SFSCs to social sustainability. However, participants’ views considerably differ regarding the economic and environmental dimensions of sustainability. These differences relate to the way the SFSCs were organised and to some degrees to regional differences attributed to the significance of SFSC in different parts of Europe. The article concludes that the spatial heterogeneity of SFSCs, including supply chain actor differences, different types and organisational forms of SFSCs as well as regional and territorial characteristics, must be taken into account and further emphasised in future policies aimed at strengthening European food chain sustainability