Plasma appearance and correlation between coffee and green tea metabolites in human subjects

Coffee and green tea are two of the most widely consumed hot beverages in the world. Their respective bioavailability has been studied separately, but absorption of their respective bioactive phenolics has not been compared. In a randomised cross-over design, nine healthy subjects drank instant coffee and green tea. Blood samples were collected over 12h and at 24h to assess return to baseline. After green tea consumption, (−)-epigallocatechin (EGC) was the major catechin, appearing rapidly in the plasma; (−)-EGC gallate (EGCg) and (−)-epicatechin (EC) were also present, but (−)-EC gallate and C were not detected. Dihydroferulic acid and dihydrocaffeic acid were the major metabolites that appeared after coffee consumption with a long time needed to reach maximum plasma concentration, suggesting metabolism and absorption in the colon. Other phenolic acid equivalents (caffeic acid (CA), ferulic acid (FA) and isoferulic acid (iFA)) were detected earlier, and they peaked at lower concentrations. Summations of the plasma area under the curves (AUC) for the measured metabolites showed 1·7-fold more coffee-derived phenolic acids than green tea-derived catechins (P=0·0014). Furthermore, we found a significant correlation between coffee metabolites based on AUC. Inter-individual differences were observed, but individuals with a high level of CA also showed a correspondingly high level of FA. However, no such correlation was observed between the tea catechins and coffee phenolic acids. Correlation between AUC and maximum plasma concentration was also significant for CA, FA and iFA and for EGCg. This implies that the mechanisms of absorption for these two classes of compounds are different, and that a high absorber of phenolic acids is not necessarily a high absorber of catechin

Traits d'histoire de vie du Tamia de Sibérie Tamias sibiricus, espèce exotique naturalisée dans la forêt de Sénart (Essone) (démographie, biologie de la reproduction, occupation de l'espace et dispersion)

Le Tamia de Sibérie, Tamias sibiricus, est un Sciuridé originaire d Asie introduit en France depuis le début des années 70. Vendu comme animal de compagnie, il a été relâché par des propriétaires dans des forêts périurbaines où il est apte à s établir. A ce jour, onze populations sont identifiées en Île-de-France et Picardie. Les conséquences de sa présence d un point de vue écologique, sanitaire et économique étant peu documentées, un programme de recherche a été initié afin de déterminer si cette espèce est envahissante et quelles sont les caractéristiques qui encouragent son établissement et son expansion. Dans ce contexte, un suivi de population par capture-marquage-recapture a été mis en place dans la Forêt de Sénart (Essonne) où se situe la plus importante population en termes d effectifs. A travers l étude de la démographie de cette population, de son mode de reproduction et d occupation de l espace, et de la dispersion des juvéniles, des traits d histoire de vie de l espèce favorisant son établissement et son expansion ont été mis en évidence. L analyse démographique a permis de caractériser la structure de la population et sa forte croissance. Les taux de survie élevés, notamment en hiver, et la fécondité croissante semblent expliquer équitablement cette augmentation. Dans un deuxième temps, la biologie de la reproduction de l espèce, étape clé du processus de naturalisation, a été étudiée. Le système d accouplement de promiscuité (polygynandrie) et les deux saisons de reproduction par an favorisent aussi son établissement. Une étude de l occupation spatiale a permis de définir l organisation mise en place entre les sexes et confirme le système de promiscuité (chevauchement entre les sexes). Concernant les modalités d expansion du Tamia de Sibérie, la fidélité au site des adultes et la faible dispersion des juvéniles semblent plutôt limitantes. Toutefois, des déplacements sur de longues distances ont été observés chez les juvéniles. Le Tamia de Sibérie présente donc des traits d histoire de vie qui encouragent fortement son établissement, néanmoins ses capacités d expansion semblent limitées.The Siberian chipmunk, Tamias sibiricus, is an Asiatic Sciurid introduced in France since the 1970 s. Sold as pet, it was released in French suburban forests where it is established. To date, eleven populations have been identified in Île-de-France and Picardie. The ecological, sanitary or economical consequences of the presence of this species are not documented; thus, a research program was initiated in order to define if the species is invasive and what are the characteristics which encourage its establishment and its expansion. In this context, a monitoring program using capture-mark-recapture methods was established in the Forest of Sénart (Essonne) where the greatest population currently exists. By studying the population demography, the reproduction, the space occupation, and the natal dispersal, life parameters promoting establishment and expansion have been identified. In a first part, the demography analysis allowed to characterize the population structure and its high growth rate. The high survival rates, especially during winter and the increasing fecundity seem to explain fairly this increase. In a second part, the reproduction biology of the species, a key step of the naturalization process, was studied. The promiscuous mating system and the two periods of reproduction per year promote also the establishment. The study of space occupation allowed to define the organization between sexes and confirmed a promiscuous system (overlap between sexes). The study of expansion process of the Siberian chipmunk showed that site fidelity and the low availability of juveniles to disperse seem to limit the expansion. However, long-distance dispersal had been observed in some juveniles. Thus, Siberian chipmunk presents life history traits which promote strongly its establishment; nevertheless its capacities of dispersion seem limited.PARIS-Museum Hist.Naturelle (751052304) / SudocSudocFranceF

Factors affecting male and female reproductive success in a chipmunk (Tamias sibiricus) with a scramble competition mating system

While sexual selection in mammals with female defense systems has historically received considerable attention, much less is known about the factors affecting reproductive success in mammalian species with scramble competition mating systems. Using mark–recapture techniques and DNA microsatellite loci to assign parentage, we examined the mating system and factors affecting the variation of the annual reproductive success in an introduced population of the Siberian chipmunk, Tamias sibiricus, a small, monomorphic, solitary squirrel. Our analyses showed that breeding females were spatially dispersed, setting the stage for a scramble competition mating system. Male reproductive success was positively associated with the size of the home range. The strength of sexual selection on this behavioral trait was very strong, equaling previous estimates for morphological traits in female defense mating systems. These findings suggest that a behavioral trait, space use, strongly influences the annual reproductive success in males, which is consistent with expectations in a scramble competition mating system. In both sexes, reproductive success was influenced by habitat, with twice as many juveniles produced in semi-open than in closed habitat, possibly due to differences in food availability between the two habitats

Le lapin de garenne dans les grands parcs paysagers de la Seine-Saint-Denis

L’histoire des relations anthropozoologiques du lapin de garenne est longue, singulière et pleine de « rebondissements ». Originaire de la péninsule ibérique, Oryctolagus cuniculus (Linnaeus, 1758) est déplacé par les hommes dès l’Antiquité sur certaines îles de la Méditerranée. À partir du Moyen Âge, le lapin est diffusé par les hommes de manière spectaculaire à travers l’Europe, notamment grâce à la multiplication des garennes. Cette diffusion se poursuivra jusqu’aux temps modernes et conte..

Évaluation des connaissances, attitudes et pratiques sur le risque d'infection à lyssavirus chez les chiroptérologues français

Journées Nationales de l'Infectiologie et Journées Nationale de Formation des ParamédicauxNational audienc

Helminth fauna of the Siberian chipmunk, Tamias sibiricus Laxmann (Rodentia, Sciuridae) introduced in suburban French forests

International audienceThe spread of an immigrant host species can be influenced both by its specific helminth parasites that come along with it and by newly acquired infections from native fauna. The Siberian chipmunk, Tamias sibiricus Laxmann (Rodentia, Sciuridae), a northeastern Eurasiatic ground nesting Sciurid, has been introduced in France for less than three decades. Thirty individuals were collected from three suburban forests in the Ile-de-France Region between 2002 and 2006. Two intestinal nematode species dominated the helminth fauna: Brevistriata skrjabini [Prevalence, P, 99% C.I., 87% (64–97%); mean intensity, M.I., 99% C.I., 43 (28–78)] and Aonchotheca annulosa [P, 47% (25–69%); M.I., 35 (3–157)]. B. skrjabini is a direct life cycle nematode species of North Eurasiatic origin, with a restricted spectrum of phylogenetically related suitable hosts. This result indicates that B. skrjabini successfully settled and spread with founder pet chipmunks maintained in captivity and released in natura. Chipmunks acquired A. annulosa, a nematode species with a large spectrum of phylogenetically unrelated suitable host species, from local Muroid rodent species with similar behavior, life-history traits and habitats. Quantitative studies are needed to evaluate the potential for both B. skrjabini and A. annulosa to impede the spread of Tamias and for B. skrjabini to favor chipmunk colonization through detrimental effects upon native co-inhabiting host species

Body size information in large-scale acoustic bat databases

Background Citizen monitoring programs using acoustic data have been useful for detecting population and community patterns. However, they have rarely been used to study broad scale patterns of species traits. We assessed the potential of acoustic data to detect broad scale patterns in body size. We compared geographical patterns in body size with acoustic signals in the bat species Pipistrellus pipistrellus. Given the correlation between body size and acoustic characteristics, we expected to see similar results when analyzing the relationships of body size and acoustic signals with climatic variables. Methods We assessed body size using forearm length measurements of 1,359 bats, captured by mist nets in France. For acoustic analyses, we used an extensive dataset collected through the French citizen bat survey. We isolated each bat echolocation call (n = 4,783) and performed automatic measures of signals, including the frequency of the flattest part of the calls (characteristic frequency). We then examined the relationship between forearm length, characteristic frequencies, and two components resulting from principal component analysis for geographic (latitude, longitude) and climatic variables. Results Forearm length was positively correlated with higher precipitation, lower seasonality, and lower temperatures. Lower characteristic frequencies (i.e., larger body size) were mostly related to lower temperatures and northern latitudes. While conducted on different datasets, the two analyses provided congruent results. Discussion Acoustic data from citizen science programs can thus be useful for the detection of large-scale patterns in body size. This first analysis offers a new perspective for the use of large acoustic databases to explore biological patterns and to address both theoretical and applied questions

Temporal variation of <em>Borrelia burgdorferi</em> sl infection in introduced Siberian chipmunks (<em>Tamias sibiricus</em>) in a suburban forest

International audienc

Conséquences de l'introduction en Ile-de-France d'un écureuil exotique, le Tamia de Sibérie, dans la dynamique de la borréliose de Lyme

International audienc

Dynamique temporelle de l’infection des petits rongeurs par<em> Borrelia burgdorferi</em> sl en forêt de Sénart

National audienc