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Role of Backyard Flocks in Transmission Dynamics of Highly Pathogenic Avian Influenza A(H5N8) Clade 2.3.4.4, France, 2016-2017.
No full textHighly pathogenic avian influenza A(H5N8) clade 2.3.4.4 spread in France during 2016-2017. We assessed the biosecurity and avian influenza virus infection status of 70 backyard flocks near H5N8-infected commercial farms. One flock was seropositive for clade 2.3.4.4. Backyard flocks linked to commercial farms had elevated risk for H5 infection
Intestinal inflammation in children with cystic fibrosis is associated with crohn's-like microbiota disturbances
No full textCystic fibrosis (CF) is a systemic genetic disease that leads to pulmonary and digestive disorders. In the majority of CF patients, the intestine is the site of chronic inflammation and microbiota disturbances. The link between gut inflammation and microbiota dysbiosis is still poorly understood. The main objective of this study was to assess gut microbiota composition in CF children depending on their intestinal inflammation. We collected fecal samples from 20 children with CF. Fecal calprotectin levels were measured and fecal microbiota was analyzed by 16S rRNA sequencing. We observed intestinal inflammation was associated with microbiota disturbances characterized mainly by increased abundances of Staphylococcus, Streptococcus, and Veillonella dispar, along with decreased abundances of Bacteroides, Bifidobacterium adolescentis, and Faecalibacterium prausnitzii. Those changes exhibited similarities with that of Crohn's disease (CD), as evidenced by the elevated CD Microbial-Dysbiosis index that we applied for the first time in CF. Furthermore, the significant over-representation of Streptococcus in children with intestinal inflammation appears to be specific to CF and raises the issue of gut-lung axis involvement. Taken together, our results provide new arguments to link gut microbiota and intestinal inflammation in CF and suggest the key role of the gut-lung axis in the CF evolution
Unraveling the effects of the gut microbiota composition and function on horse endurance physiology
No full textAn integrated analysis of gut microbiota, blood biochemical and metabolome in 52 endurance horses was performed. Clustering by gut microbiota revealed the existence of two communities mainly driven by diet as host properties showed little effect. Community 1 presented lower richness and diversity, but higher dominance and rarity of species, including some pathobionts. Moreover, its microbiota composition was tightly linked to host blood metabolites related to lipid metabolism and glycolysis at basal time. Despite the lower fiber intake, community type 1 appeared more specialized to produce acetate as a mean of maintaining the energy supply as glucose concentrations fell during the race. On the other hand, community type 2 showed an enrichment of fibrolytic and cellulolytic bacteria as well as anaerobic fungi, coupled to a higher production of propionate and butyrate. The higher butyrate proportion in community 2 was not associated with protective effects on telomere lengths but could have ameliorated mucosal inflammation and oxidative status. The gut microbiota was neither associated with the blood biochemical markers nor metabolome during the endurance race, and did not provide a biomarker for race ranking or risk of failure to finish the race
III-5 Bio-protection by one strain of m. Pulcherrima: Microbiological and chemical impacts in red wines
No full textIn oenology, bio-protection consists in adding bacteria, yeasts or a mixture of microorganisms on grape must before fermentation in order to reduce the use of chemical compounds such as sulphites.
More particularly, non-Saccharomyces yeasts are used as a total or partial alternative to sulphites.
However, scientific data capable of proving the effectiveness of adding these yeasts on grape must remain scarce. A single study in white winemaking showed that early addition of a non-Saccharomyces T. del¬brueckii strain could be a microbiological and chemical alternative to sulphites (Simonin et al., 2018).
However, there is a lack of scientific data concerning red winemaking where the process allows to leave the yeasts added during the whole winemaking. This study reports for the first time the analysis of microbio¬logical and chemical effects of one Metschnikowia pulcherrima strain, inoculated at the beginning of the red winemaking process in three wineries as an alternative to sulphiting. The implantation of the M. pulcherri¬ma was successful in all the wineries and effectively limited the development of spoilage microorganisms in the same way as the addition of sulphites. The addition of non-Saccharomyces strain could protect must and wine from oxidation as demonstrated by the proanthocyanidin and anthocyanin analysis.
Adding M. pulcherrima had no effect on wine volatile compounds and sensorial analysis. However, the un¬targeted analysis by FTICR-MS highlighted a bio-protection signature and an activation of certain metabolic pathways
Multiple C2 domains and transmembrane region proteins (MCTPs) tether membranes at plasmodesmata.
No full textIn eukaryotes, membrane contact sites (MCS) allow direct communication between organelles. Plants have evolved a unique type of MCS, inside intercellular pores, the plasmodesmata, where endoplasmic reticulum (ER)-plasma membrane (PM) contacts coincide with regulation of cell-to-cell signalling. The molecular mechanism and function of membrane tethering within plasmodesmata remain unknown. Here, we show that the multiple C2 domains and transmembrane region protein (MCTP) family, key regulators of cell-to-cell signalling in plants, act as ER-PM tethers specifically at plasmodesmata. We report that MCTPs are plasmodesmata proteins that insert into the ER via their transmembrane region while their C2 domains dock to the PM through interaction with anionic phospholipids. A Atmctp3/Atmctp4 loss of function mutant induces plant developmental defects, impaired plasmodesmata function and composition, while MCTP4 expression in a yeast Δtether mutant partially restores ER-PM tethering. Our data suggest that MCTPs are unique membrane tethers controlling both ER-PM contacts and cell-to-cell signalling
Origanum syriacum essential oil chemical polymorphism according to soil type
No full textBackground: Origanum syriacum L. is an aromatic plant growing wild in Lebanon. This species is highly used in Lebanese traditional medicine and is a staple food in Lebanese gastronomy. Due to the over-harvesting, this species has become a cultivated crop rather than being collected from the wild. This study aims to evaluate the chemical polymorphism according to soil type. Methods: Plant samples were cultivated in different soil types including manure, potting mix, professional agriculture mixture, vegetable compost, nursery soils, and natural agricultural soil inoculated with arbuscular mycorrhizal fungi. After 16 weeks of culture, fresh shoot biomass was measured. Root colonization rate was evaluated and foliar biomasses were used for essential oil (EO) extraction. EO yield was calculated and the identification of the main chemical compounds of EO samples was performed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). Results: Our findings revealed that the soil type affects the O. syriacum chemotype. Indeed, the EO samples could be divided into two groups: thymol chemotype group including manure and vegetable compost soils and non-sterilized non-inoculated EO samples, and the thymol/carvacrol chemotype including potting mix, professional agriculture mixture, nursery mixture, sterilized non-inoculated, non-sterilized inoculated, and sterilized inoculated EO samples. These results showed that manure and vegetable compost soils promoted thymol synthesis, whereas potting mix, professional agriculture mixture, and nursery mixture soils were thymol/carvacrol chemotype. Moreover, mycorrhizal inoculation increased carvacrol and reduced thymol productions in comparison to non-inoculated conditions. Additionally, mycorrhizal inoculation showed significant enhancements in mycorrhizal rates and shoot biomass production with respect to the non-sterilized soil. Conclusions: These variations confirm the influence of the edaphic conditions on the chemical components biosynthesis pathways of oregano plants. The results of this investigation could be used for determining optimal soil type, leading to a good quality herb production
Implication of vitamin A in neuroprotection of dopaminergic neurons in a rat model of Parkinson's disease
No full textParkinson's disease (PD) is caused by a loss of dopaminergic neurons in the substantia nigra pars compacta (SNc), leading to strong motor impairments. Dopaminergic neurons from the SNc project to the striatum which allow the control of voluntary movements. Vitamin A, through the action of its active metabolite, retinoic acid (RA), is involved in the development, differentiation and neuroprotection of SNc dopaminergic neurons. Additionally, retinaldehyde dehydrogenase (RALDH), the synthesis enzyme of retinoic acid, is involved in cellular detoxification. However, the cerebral bioavailability of retinoic acid decreases with aging, which downregulates RALDH expression. This may precipitate neurodegenerative processes such as those observed in Parkinson's disease. Here we hypothesize that nutritional supplementation with vitamin A normalizes brain levels of retinoic acid and thus RALDH, which exhibit a neuroprotective effect on dopaminergic neurons, to delay the progression of the disease. To test our hypothesis, we modeled Parkinson's disease with unilateral injection of 6-hydroxydopamine (6-OHDA), a toxin that selectively destroys dopaminergic neurons, into rats' striatum. Rats were supplemented or not with dietary vitamin A (20 UI/g) for 5 weeks before the lesion. Motor impairments induced by 6-OHDA and protective effect of vitamin A were quantified with the step test, cylinder test and rotarod. Extend of dopaminergic neurons degeneration was assessed with stereological analysis of tyrosine hydroxylase, the production enzyme of dopamine, staining in the striatum. To evaluate the functionality of the dopaminergic system, levels of dopamine and its metabolites were measured in the striatum with HPLC. Finally, to precisely interrogate the impact of vitamin A supplementation on RALDH enzyme, its expression and localization will be assessed with immunostaining, western blot and RT-qPCR analyses. These experiments that are still in progress will allow a precise assessment of the neuroprotective effects of vitamin A supplementation on dopaminergic neurons in a rat model of Parkinson's disease. This work may open therapeutic strategies to prevent neurodegeneration