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C-Eci: A Cubic-Eci combined clearing method for 3D follicular content analysis In the ovary
No full textDeciphering mechanisms of oocyte development in female fishes still remains challenging and a comprehensive overview of this process at the level of the organ is still needed. The recent development optical tissue clearing methods have tremendously boosted the 3D imaging of large size biological samples that are naturally opaque. However, no attempt of clearing on fish ovary that accumulates extremely high concentration of lipids within oocytes has been reported to date. To face with this ovarian-specific challenge, we combined two existing clearing methods, the non-toxic solvent-based Eci method for efficient clearing and the CUBIC method to enhance lipid removal and reduce non-specific staining. The methyl green fluorescent dye was used to stain nuclei and delineate follicles. Using this procedure (named C-Eci), ovaries of both medaka and trout could be imaged in 3D and all follicles analyzed. To our knowledge this is the first procedure elaborated for clearing and imaging fish ovary in 3D. The C-Eci methods thus provides an interesting tool for getting precise quantitative data on follicular content in fish ovary and promises to be useful for further morphological studies
Murine genetic background overcomes gut microbiota changes to explain metabolic response to high-fat diet
No full textInteractions of diet, gut microbiota, and host genetics play essential roles in the development of metabolic diseases. A/J and C57BL/6J (C57) are two mouse strains known to display different susceptibilities to metabolic disorders. In this context, we analyzed gut microbiota composition in A/J and C57 mice, and assessed its responses to high-fat diet (HFD) and antibiotic (AB) treatment. We also exchanged the gut microbiota between the two strains following AB treatment to evaluate its impact on the metabolism. We showed that A/J and C57 mice have different microbiome structure and composition at baseline. Moreover, A/J and C57 microbiomes responded differently to HFD and AB treatments. Exchange of the gut microbiota between the two strains was successful as recipients’ microbiota resembled donor-strain microbiota. Seven weeks after inoculation, the differences between recipients persisted and were still closer from the donor-strain microbiota. Despite effective microbiota transplants, the response to HFD was not markedly modified in C57 and A/J mice. Particularly, body weight gain and glucose intolerance in response to HFD remained different in the two mouse strains whatever the changes in microbiome composition. This indicated that genetic background has a much stronger impact on metabolic responses to HFD than gut microbiome composition. Vie
A PCR, qPCR, and LAMP Toolkit for the Detection of the Wheat Blast Pathogen in Seeds
No full textWheat blast is a devastating disease caused by the pathogenic fungus Pyricularia oryzae. Wheat blast first emerged in South America before more recently reaching Bangladesh. Even though the pathogen can spread locally by air-dispersed spores, long-distance spread is likely to occur via infected wheat seed or grain. Wheat blast epidemics are caused by a genetic lineage of the fungus, called the Triticum lineage, only differing from the other P. oryzae lineages by less than 1% genetic divergence. In order to prevent further spread of this pathogen to other wheat-growing areas in the world, sensitive and specific detection tools are needed to test for contamination of traded seed lots by the P. oryzae Triticum lineage. In this study, we adopted a comparative genomics approach to identify new loci specific to the P. oryzae Triticum lineage and used them to design a set of new markers that can be used in conventional polymerase chain reaction (PCR), real-time PCR, or loop-mediated isothermal amplification (LAMP) for the detection of the pathogen, with improved inclusivity and specificity compared to currently available tests. A preliminary biological enrichment step of the seeds was shown to improve the sensitivity of the tests, which enabled the detection of the target at an infection rate as low as 0.25%. Combined with others, this new toolkit may be particularly beneficial in preventing the trade of contaminated seeds and in limiting the spread of the diseas
Sophie Nicklaus, le comportement alimentaire des enfants : Newsletter du Centre INRAE de Bourgogne-Franche-Comté
No full textDigestibilité des protéines, biodisponibilité des acides aminés : comment les mesurer et maitriser leurs facteurs de variation ?
No full textMultiblock PLS-DA on fecal and plasma visible-near-infrared spectra for discriminating young bulls according to their efficiency. Preliminary results
No full textUtilisation d’une puce très basse densité (1 100 SNP) pour la sélection génomique chez 3 races de porcs françaises
No full textTo reduce genotyping costs for genomic selection, a Low-Density SNP (LD) chip, designed in 2016, is now used routinely. This panel is composed of approximately 1 100 equidistant SNPs. The relevance of this chip has been studied in French populations of the Landrace, Large White and Pietrain pig breeds. The quality of imputation was estimated by the correlation between actual and imputed genotypes and error rates. The impact of imputation on the genomic evaluations was estimated by the correlation between the genomic values obtained for the candidates with imputed genotypes, and those obtained with the high-density genotypes. Average error rates of imputation estimated on all the chromosomes were 0.03, 0.11 and 0.14 for Landrace, Large White and Pietrain, respectively. The estimated correlations between actual and imputed genotypes were relatively high at 0.93, 0.92 and 0.88 forLandrace, Large White and Pietrain populations, respectively. Correlations between genomic breeding values predicted with high-density genomic data or imputed genomic data from the LD SNP panel ranged from 0.89-0.97 for Large White and Landrace populations for reproductive traits. They were higher than those obtained for the Pietrain population (0.80 and 0.97 for production traits, r espectively). In conclusion, despite the limited number of SNPs on the low-density panel used in this study, the imputation accuracy is sufficient to use the imputed genotypes in the genomic evaluations. In practice, genotyping candidates with a LD chip isa solution for selecting future breeding pigs at lower cos
Unintended consequences of environmental policies: the case of set-aside and agricultural intensification
No full textSet-aside policies providing agronomic and ecological benefits have been mainstream practices in European agriculture. Because they may lead to intensification on cultivated land, they can however have mixed environmental effects. To evaluate the indirect impact of a set-aside policy on crop intensification, we consider two elasticity indicators with respect to set-aside subsidy: chemical input demand and intensity of input use. We estimate a structural, multi-output micro-econometric model on a panel of French farmers from 2006 to 2010, accounting for multivariate selection on crops and land use (corner solutions). We estimate both a parametric and a more robust semi-nonparametric estimator, to detect deviations from normality and homoskedasticity. Our results show that a set-aside subsidy can provide farmers with incentives to intensify their production, leading to potential adverse environmental effects
Neurofibromatosis 1 French national guidelines based on an extensive literature review since 1966.
No full textNeurofibromatosis type 1 is a relatively common genetic disease, with a prevalence ranging between 1/3000 and 1/6000 people worldwide. The disease affects multiple systems with cutaneous, neurologic, and orthopedic as major manifestations which lead to significant morbidity or mortality. Indeed, NF1 patients are at an increased risk of malignancy and have a life expectancy about 10-15 years shorter than the general population. The mainstay of management of NF1 is a patient-centered longitudinal care with age-specific monitoring of clinical manifestations, aiming at the early recognition and symptomatic treatment of complications as they occur. Protocole national de diagnostic et de soins (PNDS) are mandatory French clinical practice guidelines for rare diseases required by the French national plan for rare diseases. Their purpose is to provide health care professionals with guidance regarding the optimal diagnostic and therapeutic management of patients affected with a rare disease; and thus, harmonizing their management nationwide. PNDS are usually developed through a critical literature review and a multidisciplinary expert consensus. The purpose of this article is to present the French guidelines on NF1, making them even more available to the international medical community. We further dwelled on the emerging new evidence that might have therapeutic potential or a strong impact on NF1 management in the coming feature. Given the complexity of the disease, the management of children and adults with NF1 entails the full complement healthcare providers and communication among the various specialties