A polyphasic approach to study the dynamics of microbial population of an organic wheat sourdough during its conversion to gluten-free sourdough

To develop a method for organic gluten-free (GF) sourdough bread production, a long-term and original wheat sourdough was refreshed with GF flours. The dynamics of the sourdough microbiota during five months of back-slopping were analyzed by classical enumeration and molecular methods, including PCR-temporal temperature gel electrophoresis (PCR-TTGE), multiplex PCR, and pulsed field gel electrophoresis (PFGE). The results showed that the yeast counts remained constant, although Saccharomyces cerevisiae, present in the initial wheat sourdough, was no longer detected in the GF sourdough, while lactic acid bacteria (LAB) counts increased consistently. In the first phase, which was aimed at obtaining a GF sourdough from wheat sourdough, Lactobacillus sanfranciscensis, L. plantarum, and L. spicheri were the main LAB species detected. During the second phase, aimed at maintaining the GF sourdough, the L. plantarum and L. spicheri populations decreased whereas L. sanfranciscensis persisted and L. sakei became the predominant species. Multiplex PCRs also revealed the presence of several L. sakei strains in the GF sourdough. In a search for the origin of the LAB species, PCR-TTGE was performed on the flour samples but only L. sanfranciscensis was detected, suggesting a flour origin for this typical sourdough species. Thus, while replacement of the wheat flour by GF flour influenced the sourdough microbiota, some of the original sourdough LAB and yeast species remained in the GF sourdough. [Int Microbiol 2014; 17(1):1-9]Keywords: Lactobacillus spp. · Saccharomyces · Candida ·  sourdough · gluten-free food · organic · lactic acid bacteria · yeas

Poor glycemic control in type 2 diabetes enhances functional and compositional alterations of small, dense HDL3c

High-density lipoprotein (HDL) possesses multiple biological activities; small, dense HDL3c particles displaying distinct lipidomic composition exert potent antiatherogenic activities which can be compromised in dyslipidemic, hyperglycemic insulin-resistant states. However, it remains indeterminate (i) whether such functional HDL deficiency is related to altered HDL composition, and (ii) whether it originates from atherogenic dyslipidemia, dysglycemia, or both. In the present work we analyzed compositional characteristics of HDL subpopulations and functional activity of small, dense HDL3c particles in treatment-naïve patients with well-controlled (n=10) and poorly-controlled (n=8) type 2 diabetes (T2D) and in normolipidemic age- and sex-matched controls (n=11). Our data reveal that patients with both well- and poorly-controlled T2D displayed dyslipidemia and low-grade inflammation associated with altered HDL composition. Such compositional alterations in small, dense HDL subfractions were specifically correlated with plasma HbA1c levels. Further analysis using a lipidomic approach revealed that small, dense HDL3c particles from T2D patients with poor glycemic control displayed additional modifications of their chemical composition. In parallel, antioxidative activity of HDL3c towards oxidation of low-density lipoprotein was diminished. These findings indicate that defective functionality of small, dense HDL particles in patients with T2D is not only affected by the presence of atherogenic dyslipidemia, but also by the level of glycemic control, reflecting compositional alterations of HDL. Keywords: Antioxidative activity; Functionality; HDL; Lipidomics; Type 2 diabetes

Key Role of Polyphosphoinositides in Dynamics of Fusogenic Nuclear Membrane Vesicles

The role of phosphoinositides has been thoroughly described in many signalling and membrane trafficking events but their function as modulators of membrane structure and dynamics in membrane fusion has not been investigated. We have reconstructed models that mimic the composition of nuclear envelope precursor membranes with naturally elevated amounts of phosphoinositides. These fusogenic membranes (membrane vesicle 1(MV1) and nuclear envelope remnants (NER) are critical for the assembly of the nuclear envelope. Phospholipids, cholesterol, and polyphosphoinositides, with polyunsaturated fatty acid chains that were identified in the natural nuclear membranes by lipid mass spectrometry, have been used to reconstruct complex model membranes mimicking nuclear envelope precursor membranes. Structural and dynamic events occurring in the membrane core and at the membrane surface were monitored by solid-state deuterium and phosphorus NMR. “MV1-like” (PC∶PI∶PIP∶PIP2, 30∶20∶18∶12, mol%) membranes that exhibited high levels of PtdIns, PtdInsP and PtdInsP2 had an unusually fluid membrane core (up to 20% increase, compared to membranes with low amounts of phosphoinositides to mimic the endoplasmic reticulum). “NER-like” (PC∶CH∶PI∶PIP∶PIP2, 28∶42∶16∶7∶7, mol%) membranes containing high amounts of both cholesterol and phosphoinositides exhibited liquid-ordered phase properties, but with markedly lower rigidity (10–15% decrease). Phosphoinositides are the first lipids reported to counterbalance the ordering effect of cholesterol. At the membrane surface, phosphoinositides control the orientation dynamics of other lipids in the model membranes, while remaining unchanged themselves. This is an important finding as it provides unprecedented mechanistic insight into the role of phosphoinositides in membrane dynamics. Biological implications of our findings and a model describing the roles of fusogenic membrane vesicles are proposed

Metabolic alterations, HFE gene mutations and atherogenic lipoprotein modifications in patients with primary iron overload

Abstract Iron overload (IO) has been associated with glucose metabolism alterations and increased risk of cardiovascular disease (CVD). Primary IO is associated with mutations in the HFE gene. To which extent HFE gene mutations and metabolic alterations contribute to the presence of atherogenic lipoprotein modifications in primary IO remains undetermined. The present study aimed to assess small, dense low-density lipoprotein (LDL) levels, chemical composition of LDL and high-density lipoprotein (HDL) particles, and HDL functionality in IO patients. Eighteen male patients with primary IO and 16 sex-and age-matched controls were recruited. HFE mutations (C282Y, H63D and S65C), measures of insulin sensitivity and secretion (calculated from the oral glucose tolerance test), chemical composition and distribution profile of LDL and HDL subfractions (isolated by gradient density ultracentrifugation) and HDL functionality (as cholesterol efflux and antioxidative activity) were studied. IO patients compared with controls exhibited insulin resistance (HOMA-IR (homoeostasis model assessment-estimated insulin resistance): +93 %, P < 0.001). Metabolic profiles differed across HFE genotypes. C282Y homozygotes (n = 7) presented a reduced β-cell function and insulin secretion compared with non-C282Y patients (n = 11) (−58 % and −73 %, respectively, P < 0.05). In addition, C282Y homozygotes featured a predominance of large, buoyant LDL particles (C282Y: 43 + − 5; non-C282Y: 25 + − 8; controls: 32 + − 7 %; P < 0.001), whereas non-C282Y patients presented higher amounts of small, dense LDL (C282Y: 23 + − 5; non-C282Y: 39 + − 10; controls: 26 + − 4 %; P < 0.01). HDL particles were altered in C282Y homozygotes. However, HDL functionality was conserved. In conclusion, metabolic alterations and HFE gene mutations are involved in the presence of atherogenic lipoprotein modifications in primary IO. To what extent such alterations could account for an increase in CVD risk remains to be determined

Le tuf calcaire de La Celle-sur-Seine (Seine et Marne) : nouvelles données sur un site clé du stade 11 dans le Nord de la France

De nouvelles études morphostratigraphiques et biostratigraphiques ainsi que des datations ont été entreprises sur le célèbre dépôt de tuf calcaire de La Celle-sur-Seine afin d'obtenir une reconstruction détaillée des successions paléoenvironnementales et climatiques enregistrées dans cette formation interglaciaire du Pléistocène moyen. L'approche développée a privilégié l'aspect pluridisciplinaire afin d'exploiter la richesse paléontologique du gisement, de mieux appréhender ses caractères morphostratigraphiques et de préciser sa position chronologique. Les premiers résultats obtenus à partir des études malacologiques montrent que le dépôt, composé de tufs et de niveaux limono-argileux, s'est construit en progradant le long du versant. Ainsi l'épaisseur totale de la formation atteint près de 9 mètres. Les malacofaunes permettent de reconstituer une évolution paléoenvironnementale correspondant au début puis à l'optimum d'une phase climatique interglaciaire. Les niveaux sommitaux sont, eux, caractérisés par un net recul de la couverture forestière.La création de nouveaux profils stratigraphiques a permis la découverte dans un niveau de limon gris tufacé d'une abondante faune de mammifères accompagnée par quelques silex taillés. Cet horizon appartient à la malacozone la plus riche en taxons thermophiles qui est interprétée comme la phase optimum de l'Interglaciaire. La signification environnementale et climatique du cortège mammalogique, qui comprend en particulier de l'hippopotame et du macaque, corrobore les résultats malacologiques. L'industrie lithique est de type bifaciale en cohérence avec les récoltes de bifaces acheuléens effectuées à la fin du 19ème siècle. La composition du cortège de mollusques permet de rapprocher la faune de La Celle de "l'assemblage à Lyrodiscus", caractéristique des tufs du stade 11 dans le nord-ouest de l'Europe. Cette attribution chronologique est confirmée par les premières mesures radiométriques obtenus par U-Th sur des échantillons de tuf induré et par RPE/U-Th sur une dent de cheval. Enfin la révision des collections paléontologiques d'empreintes foliaires permet, en conjonction avec les données malacologiques, d'initier la discussion sur l'interprétation paléoclimatique du biome à Lyrodiscus. L'association floristique et faunique de La Celle qui comprend quelques taxons arboréens méditerranéens et nombre de gastéropodes éteints ou de répartition actuelle centre-européenne et océanique rend compte d'un environnement tempéré de forêt humide. La présence de ces espèces allochtones dans le nord de la France est mise en parallèle avec la durée exceptionnellement longue du Stade Isotopique Marin (SIM) 11 et de faibles amplitudes de températures saisonnières, qui auraient permis à plusieurs taxons méridionaux de coloniser cette zone septentrionale, plutôt qu'avec un climat plus tempéré que l'actuel.New morpho and biostratigraphical studies have been undertaken at the famous calcareous tufa deposit of La Celle-sur-Seine in order to obtain a detailed paleoenvironmental and climatic reconstruction from this Middle Pleistocene Interglacial formation. Multiproxy approach allows to study palaeontological contain of the tufa as well as its morphostratigraphical aspects and chronological allocation. First results from malacological study show that the tufa edificated downwards the slope reaching a total thickness of 9 metres high. Moreover molluscs show palaeoenvironmental succession corresponding to the early part of an Interglacial period followed by an optimum phase. Finally, at the top of the deposit faunas clearly indicate decrease of forest biotopes.Excavation of new profiles have allowed to discover a grey silty tufa horizon (lgt) yielding abundant mammal remains and a few lithic artefacts. This level is part of the molluscs zone 3 corresponding to the climatic optimum. Palaeoenvironmental and climatic conditions inferred from mammal assemblage (including Hippopotamus and Macaca) strengthened the malacological interpretation. The lithic industry is identified as Acheulean and appears in agreement with earliest handaxes discoveries during the late 19th century.La Celle malacological fauna belongs to the well-known MIS 11 "Lyrodiscus assemblage" in north-west Europe. This chronological allocation is confirmed by first U-series radiometric measures. Finally reappraisal of leaf print collections allows together with malacological data to discuss palaeoclimatic interpretation of the "Lyrodiscus biome". Flora and fauna from La Celle include a few mediterranean trees and several extinct gastropods together with few molluscs of central Europe modern range, allowing to describe a forest and humid lanscape. Presence of these peculiar species in northern France is thought to be related with the long length of MIS 11 and lower seasonal temperature contrast, that have allowed northern colonisation by southern species, rather than with occurrence of temperature higher than today

Development of a World Health Organization International Reference Panel for different genotypes of hepatitis E virus for nucleic acid amplification testing.

Globally, hepatitis E virus (HEV) is a major cause of acute viral hepatitis. Epidemiology and clinical presentation of hepatitis E vary greatly by location and are affected by the HEV genotype. Nucleic acid amplification technique (NAT)-based assays are important for the detection of acute HEV infection as well for monitoring chronic cases of hepatitis E. The aim of the study was to evaluate a panel of samples containing different genotypes of HEV for use in nucleic NAT-based assays. The panel of samples comprises eleven different members including HEV genotype 1a (2 strains), 1e, 2a, 3b, 3c, 3e, 3f, 4c, 4g as well as a human isolate related to rabbit HEV. Each laboratory assayed the panel members directly against the 1 World Health Organization (WHO) International Standard (IS) for HEV RNA (6329/10) which is based upon a genotype 3 a strain. The samples for evaluation were distributed to 24 laboratories from 14 different countries and assayed on three separate days. Of these, 23 participating laboratories returned a total of 32 sets of data; 17 from quantitative assays and 15 from qualitative assays. The assays used consisted of a mixture of in-house developed and commercially available assays. The results showed that all samples were detected consistently by the majority of participants, although in some cases, some samples were detected less efficiently. Based on the results of the collaborative study the panel (code number 8578/13) was established as the "1st International Reference Panel (IRP) for all HEV genotypes for NAT-based assays" by the WHO Expert Committee on Biological Standardization. This IRP will be important for assay validation and ensuring adequate detection of different genotypes and clinically important sub-genotypes of HEV

Antiquaires et recherches sur la religion romaine à l'époque du Haut-Empire

Le De Verborum Significatione de Festus conservé par un unique manuscrit incomplet et mutilé, le Farnesianus (Naples, Bibl. nat. IV. A. 3, 11e siècle) pose de nombreux problèmes d édition et de composition. Le texte est généralement complété par les excepta du moine Paul Diacre, réalisés à la fin du 8e siècle et dédiés à Charlemagne. Mais l essentiel des informations remonte à Verrius Flaccus, un célèbre grammairien entré au service d Auguste, qui sollicite de nombreux antiquaires du dernier siècle de la République et du début du principat. Les monographies très spécialisées de ces hommes sont encore citées par les compilateurs du Haut-Empire comme Pline, Aulu Gelle, Festus, et plus tardif, Macrobe et Servius. Malgré les différences de statut et des titres d ouvrages, ces érudits ont souvent écrit sur les mêmes sujets, en utilisant les mêmes outils, dont l étymologie, et en puisant aux récits des origines de Rome. Ils se retrouvent dans l entourage des hommes de pouvoir à qui ils dédient leurs travaux, et ont peut-être participé directement aux restaurations de la religion traditionnelle. L étude et la traduction de 800 articles sur 3300, qui portent sur cette religion romaine, permettent de constater que la description de la religion n est pas exhaustive, mais se concentre sur les obscurités des rites traditionnels, pour lesquelles sont accumulées les versions de différents savants. Les annexes de la thèse proposent des outils pratiques pour la manipulation de l ensemble du lexique, et un répertoire bibliographique des travaux qui portent sur des articles de Festus.The De Verborum Significatione of Festus has been preserved by only one manuscript of the 11th century (Farnesianus, Cod. Neapol. IV. A. 3), incomplete and severely damaged. But most datas date back to Verrius Flaccus, a famous grammarian teaching Augustus s grandsons. He quotes lots of antiquarians of the last century of the Republic and of the beginning on the Principate. The monographs of these men are still quoted by compilers of the Empire, such as Plinius, Aulus Gellius, Festus or Macrobius. In spite of their different social status and of the different titles, these erudites used to work on the same subjects and resorted to the same tools, such as etymology. They are advisers to powerful men they probably helped to reform traditional religion. The study and translation of 800 articles on 3300, bearing on roman religion, allow us to remark that the description of religion is not exhaustive but centered on the difficulties of traditional rituals. The annexes offer some practical tools to make the use of this lexicon easier, and, a bibliographical directory of various modern works on Festus articles.PARIS-EPHE-Sciences religieuses (751052336) / SudocSudocFranceF

Caractéristiques cliniques et résultats thérapeutiques des adénocarcinomes mucineux de l'ovaire. Etude rétrospective à propos de 129 cas traités à l'Institut Gustave Roussy (IGR) entre 1975 et 2005

REIMS-BU Santé (514542104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Comment comprenons-nous les métaphores ?

Summary : How do we understand metaphors ? This article is a review of the experimental research on metaphor. We describe briefly the concept of metaphor and present two main theories about metaphor : the comparison theory (or similarity theory) and the interaction theory. According to the comparison theory, a comparison of features between the two concepts involved in the metaphor is the fundamental process underlying the interpretation of metaphor. According to the interaction theory, a metaphor induces the emergence of features that are associated neither with the topic nor with the vehicle ofthe metaphor. In order tofind arguments infavour of one or the other theory, we present the experimental results which were obtained using two kinds ofmethods : macroscopic methods including sentence completion tasks, judgment tasks, and memory tasks ; and microscopic methods which include lexical decision tasks, reading time, and functional imaging techniques. Macroscopic methods aim at describing what the characteristics of metaphors and apprehending the resuit of metaphor interpretation. Microscopic methods try to follow the comprehension of a metaphor. While examining data, a synthesis of main factors which have been investigated (similarity, comprehensibility, context) is presenled. We conclude on the difflculty to favor one or the other theory, and the necessity to develop interdisciplinary research.Résumé Cet article a pour but de présenter un état de la recherche cognitive sur la compréhension des métaphores. Après un bref exposé des principales théories — théorie de la comparaison et théorie de l'interaction —, sont décrites les études expérimentales reposant sur deux grandes classes de méthodes : les méthodes macroscopiques incluant les tâches de compréhension de phrases, de jugement, de rappel, et les méthodes microscopiques qui incluent les tâches de décision lexicale, de temps de lecture, et les techniques d'imagerie fonctionnelle, d'introduction récente. Les premières permettent d'appréhender ce qui subsiste de l'interprétation de la métaphore, les secondes tentent d'en suivre le cours. Parallèlement à l'examen attentif des résultats obtenus par ces deux types de méthodes, un bilan des principaux facteurs étudiés (ressemblance, contexte, compréhensibilité) est présenté. On conclut sur l'impossibilité de privilégier l'une ou l'autre des deux théories et sur les perspectives qu'offriraient les rapprochements disciplinaires. Mots-clés : compréhension des métaphores, comparaison, émergence de représentations.Gineste M.-D., Scart-Lhomme Véronique. Comment comprenons-nous les métaphores ?. In: L'année psychologique. 1999 vol. 99, n°3. pp. 447-492

Specific roles of phosphatidylglycerols in hosts and microbes

International audiencePhosphatidylglycerols (PGs) are specific phospholipids bearing negatively charged polar headgroups. Although recognized for long as a major lipid component of membranes in bacteria, it is considered a minor lipid in higher eukaryotes, due to its low abundance in biological fluids or tissues. However, new sensitive lipidomic approaches now provide tools for accurate quantification of PGs in biological samples, and this is likely to uncover new roles for these phospholipids in the near future. This paper reviews our present knowledge in PG function, from studies in microbes and eukaryotic cells, and gathers in one place a diverse range of information spread across many fields. The physical properties of PGs, their biological distribution and molecular functions make them potential actors in host-microbe interaction