Evaluation of the limitations and methods to improve rapid phage-based detection of viable Mycobacterium avium subsp. paratuberculosis in the blood of experimentally infected cattle

Background Disseminated infection and bacteraemia is an underreported and under-researched aspect of Johne’s disease. This is mainly due to the time it takes for Mycobacterium avium subsp. paratuberculosis (MAP) to grow and lack of sensitivity of culture. Viable MAP cells can be detected in the blood of cattle suffering from Johne’s disease within 48 h using peptide-mediated magnetic separation (PMMS) followed by bacteriophage amplification. The aim of this study was to demonstrate the first detection of MAP in the blood of experimentally exposed cattle using the PMMS-bacteriophage assay and to compare these results with the immune response of the animal based on serum ELISA and shedding of MAP by faecal culture. Results Using the PMMS-phage assay, seven out of the 19 (37 %) MAP-exposed animals that were tested were positive for viable MAP cells although very low numbers of MAP were detected. Two of these animals were positive by faecal culture and one was positive by serum ELISA. There was no correlation between PMMS-phage assay results and the faecal and serum ELISA results. None of the control animals (10) were positive for MAP using any of the four detection methods. Investigations carried out into the efficiency of the assay; found that the PMMS step was the limiting factor reducing the sensitivity of the phage assay. A modified method using the phage assay directly on isolated peripheral blood mononuclear cells (without PMMS) was found to be superior to the PMMS isolation step. Conclusions This proof of concept study has shown that viable MAP cells are present in the blood of MAP-exposed cattle prior to the onset of clinical signs. Although only one time point was tested, the ability to detect viable MAP in the blood of subclinically infected animals by the rapid phage-based method has the potential to increase the understanding of the pathogenesis of Johne’s disease progression by warranting further research on the presence of MAP in blood

Melanosome transfer to keratinocytes as a valuable target to control skin pigmentation: role of 6-phosphogalactose

International audienc

RIVA (Risques d'Invasions en Vignobles Aquitains) : la présence confirmée d'Orientus ishidae, vecteur potentiel de la flavescence dorée

Les invasions biologiques sont souvent la source d’émergences nouvelles de maladies, et le résultat d’activités humaines et des changements globaux (e.g. changements climatiques, d’échanges commerciaux, d’occupation des terres, de pratiques phytosanitaires). C’est particulièrement vrai historiquement pour les vignobles français et bordelais, pour lesquels la plupart des ravageurs, vecteurs ou maladies de la vigne, ont été le résultat d’introductions plus ou moins récentes. Le projet RIVA (Risques d’Invasions en Vignobles Aquitain) vise à optimiser la mise en place de programmes d’épidémio-surveillance en 2015 et 2016, sur la partie sud du vignoble bordelais, région du Sauternais et des Graves. Son objectif était de détecter l’apparition ou la progression d'espèces invasives d'insectes ravageurs et vecteurs, en se focalisant sur des espèces à forts potentiels de risques pour la viticulture. Basé sur deux campagnes de surveillance menées dans la partie sud du vignoble bordelais (i.e., région du Sauternais) et à l’aide de différentes techniques de piégeage, ce projet s’est intéressé à la surveillance de différentes espèces : les espèces vectrices de la Flavescence dorée (Scaphoideus titanus et Orientus ishidae), la drosophile japonaise (Drosophila suzukii) et la mouche africaine de la figue (Zaprionus indianus), le fulgore du stolbur (Hyalesthes obsoletus) et différentes espèces de Cixiidae potentiellement vectrices du phytoplasme du bois noir, une chenille de papillon mineuse de feuilles introduite en 2006 en Italie (Antispila oinophylla), et les vecteurs potentiels de la maladie de Pierce (Xyllela fastidiosa). Les deux années de campagne ont permis d’identifier une large diversité de cicadelles avec 73 espèces collectées en 2015 et 78 en 2016. Nos résultats ont également mis en évidence la présence chronique d’O. ishidae sur certaines parcelles surveillées et ont confirmé que des proportions non négligeables d’individus capturés étaient porteuses d’une des souches du phytoplasme responsable de la Flavescence dorée

RIVA (Risques d'Invasions en Vignobles Aquitains) : la présence confirmée d'Orientus ishidae, vecteur potentiel de la flavescence dorée

Les invasions biologiques sont souvent la source d’émergences nouvelles de maladies, et le résultat d’activités humaines et des changements globaux (e.g. changements climatiques, d’échanges commerciaux, d’occupation des terres, de pratiques phytosanitaires). C’est particulièrement vrai historiquement pour les vignobles français et bordelais, pour lesquels la plupart des ravageurs, vecteurs ou maladies de la vigne, ont été le résultat d’introductions plus ou moins récentes. Le projet RIVA (Risques d’Invasions en Vignobles Aquitain) vise à optimiser la mise en place de programmes d’épidémio-surveillance en 2015 et 2016, sur la partie sud du vignoble bordelais, région du Sauternais et des Graves. Son objectif était de détecter l’apparition ou la progression d'espèces invasives d'insectes ravageurs et vecteurs, en se focalisant sur des espèces à forts potentiels de risques pour la viticulture. Basé sur deux campagnes de surveillance menées dans la partie sud du vignoble bordelais (i.e., région du Sauternais) et à l’aide de différentes techniques de piégeage, ce projet s’est intéressé à la surveillance de différentes espèces : les espèces vectrices de la Flavescence dorée (Scaphoideus titanus et Orientus ishidae), la drosophile japonaise (Drosophila suzukii) et la mouche africaine de la figue (Zaprionus indianus), le fulgore du stolbur (Hyalesthes obsoletus) et différentes espèces de Cixiidae potentiellement vectrices du phytoplasme du bois noir, une chenille de papillon mineuse de feuilles introduite en 2006 en Italie (Antispila oinophylla), et les vecteurs potentiels de la maladie de Pierce (Xyllela fastidiosa). Les deux années de campagne ont permis d’identifier une large diversité de cicadelles avec 73 espèces collectées en 2015 et 78 en 2016. Nos résultats ont également mis en évidence la présence chronique d’O. ishidae sur certaines parcelles surveillées et ont confirmé que des proportions non négligeables d’individus capturés étaient porteuses d’une des souches du phytoplasme responsable de la Flavescence dorée

Action of Mangifera indica Leaf Extract on Acne-Prone Skin through Sebum Harmonization and Targeting C. acnes

(1) Background: Preclinical studies report that the ethanolic fraction from Mangifera indica leaves is a potential anti-acne agent. Nevertheless, the biological activity of Mangifera indica leaves has scarcely been investigated, and additional data are needed, especially in a clinical setting, for establishing the actual effectiveness of Mangifera indica extract as an active component of anti-acne therapy. (2) Methods: The evaluation of the biological activity of Mangifera indica extract was carried out through different experimental phases, which comprised in silico, in vitro, ex vivo and clinical evaluations. (3) Results: In silico and in vitro studies allowed us to identify the phytomarkers carrying the activity of seboregulation and acne management. Results showed that Mangifera indica extract reduced lipid production by 40% in sebocytes, and an improvement of the sebum quality was reported after the treatment in analyses performed on sebaceous glands from skin explants. The evaluation of the sebum quantity and quality using triglyceride/free fatty acid analysis conducted on Caucasian volunteers evidenced a strong improvement and a reduction of porphyrins expression. The C. acnes lipase activity from a severe acne phylotype was evaluated in the presence of Mangifera indica, and a reduction by 29% was reported. In addition, the analysis of the skin microbiota documented that Mangifera indica protected the microbiota equilibrium while the placebo induced dysbiosis. (4) Conclusions: Our results showed that Mangifera indica is microbiota friendly and efficient against lipase activity of C. acnes and supports a role for Mangifera indica in the therapeutic strategy for prevention and treatment of acne

SNORD116 and growth hormone therapy impact IGFBP7 in Prader–Willi syndrome

International audiencePurpose: Prader-Willi syndrome (PWS) is a neurodevelopmental disorder with hypothalamic dysfunction due to deficiency of imprinted genes located on the 15q11-q13 chromosome. Among them, the SNORD116 gene appears critical for the expression of the PWS phenotype. We aimed to clarify the role of SNORD116 in cellular and animal models with regard to growth hormone therapy (GHT), the main approved treatment for PWS.Methods: We collected serum and induced pluripotent stem cells (iPSCs) from GH-treated PWS patients to differentiate into dopaminergic neurons, and in parallel used a Snord116 knockout mouse model. We analyzed the expression of factors potentially linked to GH responsiveness.Results: We found elevated levels of circulating IGFBP7 in naive PWS patients, with IGFBP7 levels normalizing under GHT. We found elevated IGFBP7 levels in the brains of Snord116 knockout mice and in iPSC-derived neurons from a SNORD116-deleted PWS patient. High circulating levels of IGFBP7 in PWS patients may result from both increased IGFBP7 expression and decreased IGFBP7 cleavage, by downregulation of the proconvertase PC1.Conclusion: SNORD116 deletion affects IGFBP7 levels, while IGFBP7 decreases under GHT in PWS patients. Modulation of the IGFBP7 level, which interacts with IGF1, has implications in the pathophysiology and management of PWS under GHT

Amniotic fluid peptides predict postnatal kidney survival in developmental kidney disease

Although a rare disease, bilateral congenital anomalies of the kidney and urinary tract (CAKUT) are the leading cause of end stage kidney disease in children. Ultrasound-based prenatal prediction of postnatal kidney survival in CAKUT pregnancies is far from accurate. To improve prediction, we conducted a prospective multicenter peptidome analysis of amniotic fluid spanning 140 evaluable fetuses with CAKUT. We identified a signature of 98 endogenous amniotic fluid peptides, mainly composed of fragments from extracellular matrix proteins and from the actin binding protein thymosin-β4. The peptide signature predicted postnatal kidney outcome with an area under the curve of 0.96 in the holdout validation set of patients with CAKUT with definite endpoint data. Additionally, this peptide signature was validated in a geographically independent sub-cohort of 12 patients (area under the curve 1.00) and displayed high specificity in non-CAKUT pregnancies (82 and 94% in 22 healthy fetuses and in 47 fetuses with congenital cytomegalovirus infection respectively). Change in amniotic fluid thymosin-β4 abundance was confirmed with ELISA. Knockout of thymosin-β4 in zebrafish altered proximal and distal tubule pronephros growth suggesting a possible role of thymosin β4 in fetal kidney development. Thus, recognition of the 98-peptide signature in amniotic fluid during diagnostic workup of prenatally detected fetuses with CAKUT can provide a long-sought evidence base for accurate management of the CAKUT disorder that is currently unavailable.</p

Amniotic fluid peptides predict postnatal kidney survival in developmental kidney disease

International audienceAlthough a rare disease, bilateral congenital anomalies of the kidney and urinary tract (CAKUT) are the leading cause of end stage kidney disease in children. Ultrasound-based prenatal prediction of postnatal kidney survival in CAKUT pregnancies is far from accurate. To improve prediction, we conducted a prospective multicenter peptidome analysis of amniotic fluid spanning 140 evaluable fetuses with CAKUT. We identified a signature of 98 endogenous amniotic fluid peptides, mainly composed of fragments from extracellular matrix proteins and from the actin binding protein thymosin-β4. The peptide signature predicted postnatal kidney outcome with an area under the curve of 0.96 in the holdout validation set of patients with CAKUT with definite endpoint data. Additionally, this peptide signature was validated in a geographically independent sub-cohort of 12 patients (area under the curve 1.00) and displayed high specificity in non-CAKUT pregnancies (82 and 94% in 22 healthy fetuses and in 47 fetuses with congenital cytomegalovirus infection respectively). Change in amniotic fluid thymosin-β4 abundance was confirmed with ELISA. Knockout of thymosin-β4 in zebrafish altered proximal and distal tubule pronephros growth suggesting a possible role of thymosin β4 in fetal kidney development. Thus, recognition of the 98-peptide signature in amniotic fluid during diagnostic workup of prenatally detected fetuses with CAKUT can provide a long-sought evidence base for accurate management of the CAKUT disorder that is currently unavailable