Publications by authors named "F Berthelot"

The long-term dynamics of predator populations may be driven by fluctuations in resource availability and reflect ecosystem changes such as those induced by climate change. The Icelandic Arctic fox (Vulpes lagopus) population has known major fluctuations in size since the 1950s. Using stable isotopes analysis of bone collagen over a long-time series (1979-2018), we aimed at identifying the main resources used by Icelandic Arctic foxes during periods of growth and decline to assess if the variations in their population size are linked to fluctuations in the availability of resources.

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In mammals, desynchronized circadian rhythm leads to various biological symptoms. In skin and hair, human epidermal stem cell function in vitro is regulated by circadian oscillations, and thus contributes to tissue aging when deregulated. In mice, circadian arrhythmia of hair follicle stem cells contributes to age-related hair follicle cycling defects.

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The aim of this study was to identify genetic and non genetic factors which might affect results of embryo production of Large White (LW) cyclic gilts from data collected in one herd during 6 years. Donors (n=1060) were synchronized with a progestogen treatment and luteolysis was induced 13-15 days later by 2 injections of cloprostenol. To stimulate follicular development 800IU eCG was then injected 24h later, followed by 500IU hCG 48h later.

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Polymorphonuclear neutrophils (PMN) play a key role in host defenses against invading microorganisms but also potentiate inflammatory reactions in case of excessive or misdirected responses. Release of the alarmin high-mobility group box 1 (HMGB1) by cells that die at an inflammatory site may act as an alert signal for the immune system. We studied the effect of HMGB1 on human PMN migration, using whole-blood samples to avoid cell activation associated with isolation procedures.

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Unhatched blastocysts from Large White hyperprolific gilts (n=103) were identified, measured and vitrified using the Open Pulled Straw (OPS) technique to evaluate the effects of the collected blastocyst size and cryoprotectant concentrations used for vitrification, and the number of embryos transferred per recipient. Vitrified/warmed blastocyst viability was estimated in vitro, as the percentage of embryos developing after 72h, and in vivo, on pregnancy Day 30. In the in vitro study, we compared the use of three cryoprotectant concentrations (16.

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