Ouverture du colloque par Christian Robin, membre de l'Institut et François BRON, directeur d'études à l'École Pratique des Hautes Études. : Treizième Rencontres sabéennes: Actualités de la recherche sur l'archéologie et l'épigraphie de l'Arabie ancienne (colloque organisé par l'UMR 8167 "Orient et Méditerranée").

Corpus "Colloques programme AAR"Le colloque "Rencontres Sabéennes" est organisé depuis douze ans par différents centres de recherche qui s'intéressent à la civilisation de l'Arabie du Sud préislamique. Ce colloque permet aux chercheurs d'échanger régulièrement des informations sur l'avancement des recherches dans leur domaine et sur toutes les dernières découvertes sur le terrain, puis de discuter des sujets définis dans le cadre des ateliers thématiques. PRESIDENCE: Christian ROBIN (Membre de l'Institut, Directeur de recherche au CNRS, directeur de l'équipe UMR 8167 - Orient et Méditerranée, domaine de recherche : histoire et épigraphie sud-arabique). ORGANISATION SCIENTIFIQUE: Iwona GAJDA (Chargée de recherche au CNRS, Laboratoire des Etudes sémitiques anciennes, UMR 8167); François BRON (Directeur d'études à l'EPHE, IVe section); Guillaume CHARLOUX (Ingénieur de recherche au CNRS, UMR 8167); Jérémie SCHIETTECATTE (Post-doctorant au CNRS)

Bcl-2 overexpression in type II epithelial cells does not prevent hyperoxia-induced acute lung injury in mice

Bcl-2 is an anti-apoptotic molecule preventing oxidative stress damage and cell death. We have previously shown that Bcl-2 is able to prevent hyperoxia-induced cell death when overexpressed in a murine fibrosarcoma cell line L929. We hypothesized that its specific overexpression in pulmonary epithelial type II cells could prevent hyperoxia-induced lung injury by protecting the epithelial side of the alveolo-capillary barrier. In the present work, we first showed that in vitro Bcl-2 can rescue murine pulmonary epithelial cells (MLE12) from oxygen-induced cell apoptosis, as shown by analysis of LDH release, annexin V/propidium staining, and caspase-3 activity. We then generated transgenic mice overexpressing specifically Bcl-2 in lung epithelial type II cells under surfactant protein C (SP-C) promoter (Tg-Bcl-2) and exposed them to hyperoxia. Bcl-2 did not hinder hyperoxia-induced mitochondria and DNA oxidative damage of type II cell in vivo. Accordingly, lung damage was identical in both Tg-Bcl-2 and littermate mice strains, as measured by lung weight, bronchoalveolar lavage, and protein content. Nevertheless, we observed a significant lower number of TUNEL-positive cells in type II cells isolated from Tg-Bcl-2 mice exposed to hyperoxia compared with cells isolated from littermate mice. In summary, these results show that although Bcl-2 overexpression is able to prevent hyperoxia-induced cell death at single cell level in vitro and ex vivo, it is not sufficient to prevent cell death of parenchymal cells and to protect the lung from acute damage in mice

Screening for retinopathy of prematurity: Insight into optimizing screening

International audiencePurpose: To determine the factors influencing the time from preterm birth and retinopathy of prematurity (ROP) detection to optimize the timing of the initial screening. Methods: This multicenter retrospective study enrolled preterm infants born before 32 weeks of gestational age (GA) and/or weighing less than 1,500 g between January 1, 2011, and December 31, 2015. ROP screening was performed using fundus photography with a wide-field camera. Population a nd follow-up characteristics were recorded. Results: Among the 1,266 preterm infants observed, 795 were retained for analysis. One hundred seventy-four (21.6%) cases of ROP were detected with the first examination performed at 32.3 +/- 1.6 weeks of postmenstrual age (PMA) and 5.4 +/- 1.0 weeks of postnatal age (PNA). The first signs of ROP were detected at 34.0 +/- 1.9 weeks of PMA and 7.2 +/- 1.8 weeks of PNA, respectively. In the multivariate analysis, an older GA, a longer duration of mechanical ventilation, and a lower birth weight were correlated with a longer time between preterm birth and ROP detection (p < 0.0001, p < 0.0001, and p = 0.0359, respectively). Conclusion: The first examination for ROP screening should be individualized to fit the first screening examination as closely as possible to the first signs of ROP in order to avoid unnecessary examinations without missing ROP

Salivary microbiome of healthy women of reproductive age

ABSTRACT The human salivary microbial community plays a crucial role in local and systemic diseases. Biological and lifestyle factors such as menstrual cycle, oral hygiene, and smoking have been documented to impact this community. However, while hormonal contraceptives are the most prescribed drug in healthy women and intimate partners play key roles in microbial exchange between humans, their impact on the salivary microbiome of women of reproductive age have been understudied. Additionally, the role of other lifestyle factors such as diet, allergies, age, and stress on the saliva microbiome of the general population is not well understood. Here, we studied the salivary microbiome of 255 healthy women of reproductive age using self-sampling kits and 16S rRNA amplicon sequencing combined with questionnaires on lifestyle and host-related parameters. A preserved salivary bacterial community of 12 genera (Actinobacillus, Actinomyces, Alloprevotella, Campylobacter, Fusobacterium, Gemella, Granulicatella, Leptotrichia, Neisseria, Prevotella, Streptococcus, and Veillonella) was identified. Contrary to what we expected, the number of intimate partners or specific contraceptive use did not have a major impact on these bacterial communities. However, recent use of oral antibiotics was associated with a significant decrease in richness at genus level and increase in mean relative abundances of several taxa. Being stressed or nervous was associated with a significantly increased richness of the salivary microbiome at the level of amplicon sequencing variants . Nevertheless, these associations with host-related and lifestyle variables only appeared to be subtle, suggesting that the salivary microbiome is mainly driven by the buccal environment and health status of an individual. IMPORTANCE The salivary microbiome has been proven to play a crucial role in local and systemic diseases. Moreover, the effects of biological and lifestyle factors such as oral hygiene and smoking on this microbial community have already been explored. However, what was not yet well understood was the natural variation of the saliva microbiome in healthy women and how this is associated with specific use of hormonal contraception and with the number of different sexual partners with whom microbiome exchange is expected regularly. In this paper, we characterized the salivary microbiome of 255 healthy women of reproductive age using an in-depth questionnaire and self-sampling kits. Using the large metadata set, we were able to investigate the associations of several host-related and lifestyle variables with the salivary microbiome profiles. Our study shows a high preservation between individuals

The nasal mutualist Dolosigranulum pigrum AMBR11 supports homeostasis via multiple mechanisms

Summary: Comparing the nasal microbiome of healthy individuals and chronic rhinosinusitis (CRS) patients revealed Dolosigranulum pigrum as a species clearly associated with nasal health, although isolates obtained from healthy individuals are scarce. In this study, we explored the properties of this understudied lactic acid bacterium by integrating comparative genomics, habitat mining, cultivation, and functional characterization of interaction capacities. Mining 10.000 samples from the Earth Microbiome Project of 17 habitat types revealed that Dolosigranulum is mainly associated with the human nasal cavity. D. pigrum AMBR11 isolated from the nose of a healthy individual exerted antimicrobial activity against Staphylococcus aureus, decreased proinflammatory cytokine production in airway epithelial cells, and Galleria mellonella larvae mortality induced by this important nasal pathobiont. Furthermore, the strain protected the nasal barrier function in a mouse model using interleukin-4 as disruptive cytokine. Hence, D. pigrum AMBR11 is a mutualist with high potential as topical live biotherapeutic product

Different phenotypes in dermatomyositis associated with anti-MDA5 antibody

International audienceObjectives The predominance of extramuscular manifestations (e.g., skin rash, arthralgia, interstitial lung disease [ILD]) as well as the low frequency of muscle signs in anti–melanoma differentiation-associated gene 5 antibody–positive (anti-MDA5+) dermatomyositis caused us to question the term myositis-specific antibody for the anti-MDA5 antibody, as well as the homogeneity of the disease. Methods To characterize the anti-MDA5+ phenotype, an unsupervised analysis was performed on anti-MDA5+ patients (n = 83/121) and compared to a group of patients with myositis without anti-MDA5 antibody (anti-MDA5−; n = 190/201) based on selected variables, collected retrospectively, without any missing data. Results Within anti-MDA5+ patients (n = 83), 3 subgroups were identified. One group (18.1%) corresponded to patients with a rapidly progressive ILD (93.3%; p < 0.0001 across all) and a very high mortality rate. The second subgroup (55.4%) corresponded to patients with pure dermato-rheumatologic symptoms (arthralgia; 82.6%; p < 0.01) and a good prognosis. The third corresponded to patients, mainly male (72.7%; p < 0.0001), with severe skin vasculopathy, frequent signs of myositis (proximal weakness: 68.2%; p < 0.0001), and an intermediate prognosis. Raynaud phenomenon, arthralgia/arthritis, and sex permit the cluster appurtenance (83.3% correct estimation). Nevertheless, an unsupervised analysis confirmed that anti-MDA5 antibody delineates an independent group of patients (e.g., dermatomyositis skin rash, skin ulcers, calcinosis, mechanic's hands, ILD, arthralgia/arthritis, and high mortality rate) distinct from anti-MDA5− patients with myositis. Conclusion Anti-MDA5+ patients have a systemic syndrome distinct from other patients with myositis. Three subgroups with different prognosis exist