Karsts, Paysages et Préhistoire

Collection edytem n°13Les Gorges de l’Ardèche. Quelle pouvait être l’impression d’un Homme parcourant celles-ci il y a plus de 30 000ans ? Quel regard portait-il sur ces versants abrupts, ces roches calcaires aux formes spectaculaires et ses nombreuxporches et autres abris sous roche ? Quelle conscience avait-il de leurs prolongements souterrains, dans la pénombred’abord, dans l’obscurité des grottes ensuite ? Force est de relever que ces différentes interrogations n’ont pas deréponse car quels que soient les modes d’investigation, il n’est guère possible de reconstituer ce qui est au plus profondde nous, les pensées, et ce d’autant moins si elles sont contemporaines d’une période sans écrit, comme c’est lecas de la Préhistoire. Cette absence de réponse ne signifie pas qu’il ne faille pas se pencher sur ces questions, bienau contraire, et sur la place des paysages, des monuments naturels, de lieux particuliers comme les grottes dans leschoix des Hommes de la Préhistoire pour les explorer, les aménager, les utiliser comme supports de représentationset de transmission des savoirs. Ne pouvant répondre directement à ces interrogations, il est nécessaire de définir desmodes de recherche permettant de bâtir des hypothèses les plus robustes possibles pour appréhender au mieux lesreprésentations et les actions des Hommes de la Préhistoire. La robustesse de ces hypothèses repose, à la fois, sur lesdonnées produites par les différents champs de recherche souhaitant s’investir sur ces questions et sur la multiplicitédes travaux sur différents terrains et aires culturelles. Cet ouvrage s’inscrit dans cette démarche en croisant différentsregards sur les paysages et patrimoines du Sud-Ardèche

Aspergillus fumigatus stimulates the NLRP3 inflammasome through a pathway requiring ROS production and the Syk tyrosine kinase

Invasive aspergillosis (IA) is a life-threatening disease that occurs in immunodepressed patients when infected with Aspergillus fumigatus. This fungus is the second most-common causative agent of fungal disease after Candida albicans. Nevertheless, much remains to be learned about the mechanisms by which A. fulmigatus activates the innate immune system. We investigated the inflammatory response to conidia and hyphae of A. fumigatus and specifically, their capacity to trigger activation of an inflammasome. Our results show that in contrast to conidia, hyphal fragments induce NLRP3 inflammasome assembly, caspase-1 activation and IL-1β release from a human monocyte cell line. The ability of Aspergillus hyphae to activate the NLRP3 inflammasome in the monocytes requires K+ efflux and ROS production. In addition, our data show that NLRP3 inflammasome activation as well as pro-IL-1β expression relies on the Syk tyrosine kinase, which is downstream from the pathogen recognition receptor Dectin-1, reinforcing the importance of Dectin-1 in the innate immune response against fungal infection. Furthermore, we show that treatment of monocytes with corticosteroids inhibits transcription of the gene encoding IL-1β. Thus, our data demonstrate that the innate immune response against A. fumigatus infection involves a two step activation process, with a first signal promoting expression and synthesis of pro-IL-1β; and a second signal, involving Syk-induced activation of the NLRP3 inflammasome and caspase-1, allowing processing and secretion of the mature cytokine

Salivary biomarkers for the diagnosis and monitoring of neurological diseases

Current research efforts on neurological diseases are focused on identifying novel disease biomarkers to aid in diagnosis, provide accurate prognostic information and monitor disease progression. With advances in detection and quantification methods in genomics, proteomics and metabolomics, saliva has emerged as a good source of samples for detection of disease biomarkers. Obtaining a sample of saliva offers multiple advantages over the currently tested biological fluids as it is a non-invasive, painless and simple procedure that does not require expert training or harbour undesirable side effects for the patients. Here, we review the existing literature on salivary biomarkers and examine their validity in diagnosing and monitoring neurodegenerative and neuropsychiatric disorders such as autism and Alzheimer\u27s, Parkinson\u27s and Huntington\u27s disease. Based on the available research, amyloid beta peptide, tau protein, lactoferrin, alpha-synuclein, DJ-1 protein, chromogranin A, huntingtin protein, DNA methylation disruptions, and micro-RNA profiles display a reliable degree of consistency and validity as disease biomarkers

Immunotherapies for Neurodegenerative Diseases

The current treatments for neurodegenerative diseases are mostly symptomatic without affecting the underlying cause of disease. Emerging evidence supports a potential role for immunotherapy in the management of disease progression. Numerous reports raise the exciting prospect that either the immune system or its derivative components could be harnessed to fight the misfolded and aggregated proteins that accumulate in several neurodegenerative diseases. Passive and active vaccinations using monoclonal antibodies and specific antigens that induce adaptive immune responses are currently under evaluation for their potential use in the development of immunotherapies. In this review, we aim to shed light on prominent immunotherapeutic strategies being developed to fight neuroinflammation-induced neurodegeneration, with a focus on innovative immunotherapies such as vaccination therapy

Aerobic oxidation of 1,6-hexanediol to adipic acid over Au-based catalysts: the role of basic supports

1,6-Hexanediol is a relevant building blocks that could be obtained from biomass and transformed under base free conditions into adipic acid used for polymer synthesis

Gurzil

Divinité chez les Laguatan* de Tripolitaine d’après Corippe (Johan., V, 22-26). Au moment d’engager le combat, les Laguatan lâchaient sur l’ennemi un taureau représentant leur dieu Gurzil. Ce dieu était né de l’accouplement du dieu Amon*, sans doute celui de Siwa*, et d’une vache. Cette divinité jouissait d’un culte organisé qui semble avoir dépassé celui qui était rendu aux dieux locaux africains ou aux simples génies*. Corippe mentionne, en effet, chez les Laguatan, la présence d’idoles en ..

Modeling Edar expression reveals the hidden dynamics of tooth signaling center patterning.

When patterns are set during embryogenesis, it is expected that they are straightly established rather than subsequently modified. The patterning of the three mouse molars is, however, far from straight, likely as a result of mouse evolutionary history. The first-formed tooth signaling centers, called MS and R2, disappear before driving tooth formation and are thought to be vestiges of the premolars found in mouse ancestors. Moreover, the mature signaling center of the first molar (M1) is formed from the fusion of two signaling centers (R2 and early M1). Here, we report that broad activation of Edar expression precedes its spatial restriction to tooth signaling centers. This reveals a hidden two-step patterning process for tooth signaling centers, which was modeled with a single activator-inhibitor pair subject to reaction-diffusion (RD). The study of Edar expression also unveiled successive phases of signaling center formation, erasing, recovering, and fusion. Our model, in which R2 signaling center is not intrinsically defective but erased by the broad activation preceding M1 signaling center formation, predicted the surprising rescue of R2 in Edar mutant mice, where activation is reduced. The importance of this R2-M1 interaction was confirmed by ex vivo cultures showing that R2 is capable of forming a tooth. Finally, by introducing chemotaxis as a secondary process to RD, we recapitulated in silico different conditions in which R2 and M1 centers fuse or not. In conclusion, pattern formation in the mouse molar field relies on basic mechanisms whose dynamics produce embryonic patterns that are plastic objects rather than fixed end points