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121.
Jean-Marc Cavaillon Fabrice Chrétien 《Microbes and infection / Institut Pasteur》2019,21(5-6):213-221
Sepsis remains a contemporary threat, and its frequency remains high amongst an aging population. Its definition has been regularly revisited, but the impact of the translational research studying it remains very modest compared to the results seen after the introduction of hygiene and the use of antibiotics. In the past, the main forms of sepsis were hospital gangrene (also known as nosocomial fever or putrid fever) that affected the wounded, and puerperal fever that affected women shortly after delivery. In 1858, Armand Trousseau stated that these two pathologies were identical. Lucrezia Borgia, who died in 1519, is undoubtedly the most famous woman to die from puerperal fever. The notion of sepsis as a real epidemic was deplored. For decades doctors remained deaf to the recommendations of their clairvoyant colleagues who advocated for the use of hygienic measures. It was as early as 1795 that Alexander Gordon (UK) and later in 1843, Oliver Holmes (USA), called for the use of hygienic practices. In 1847, Ignaz Semmelweis, a Hungarian physician, provided an irrefutable demonstration of the importance of hygiene in the prevention of contamination by the hands of the practitioners. But Ignaz Semmelweis' life was a tragedy, his fight against the medical nomenklatura was a tragedy, and his death was a tragedy! Nowadays, Ignaz Semmelweis is receiving the honor that he deserves, but never received during his life. Carl Mayrhofer, Victor Feltz, and Léon Coze were the first to associate the presence of bacteria with sepsis. These observations were confirmed by Louis Pasteur who, thanks to his prestige, had a great influence on how to undertake measures to prevent infections. He inspired Joseph Lister who reduced mortality associated with surgery, particularly amputation, by utilizing antiseptic methods. 相似文献
122.
Félix-Faure Jim Gaillard Jérémie Descloux Stéphane Chanudet Vincent Poirel Alain Baudoin Jean-Marc Avrillier Jean-Noël Millery Annie Dambrine Etienne 《Ecosystems》2019,22(2):312-330
Ecosystems - When a water reservoir is created, the pre-existing soils and vegetation are flooded. Here, we took advantage of the complete emptying of the Sarrans Reservoir, which was flooded... 相似文献
123.
Sabrina Renaud Claire Delpine Ronan Ledevin Benoît Pisanu Jean‐Pierre Qur Emilie A. Hardouin 《Journal of Zoological Systematics and Evolutionary Research》2019,57(4):989-999
The house mouse (Mus musculus domesticus), as a successful invasive species worldwide, has to forage a variety of resources. Subantarctic mice display among the most notable diet shift from the usual omnivorous–granivorous diet, relying on a larger proportion of terrestrial animal prey. In agreement, a recent study of their mandible morphology evidenced an evolution of their mandible shape to optimize incisor biting and hence seize preys. Here, the incisors themselves are the focus of a morphometric analysis combined with a 3D study of their internal structure, aiming at a comparison between subantarctic populations (Guillou island, Kerguelen archipelago) with a range of western European continental, commensal mice. The predatory foraging behavior of Guillou mice was indeed associated with a sharper bevel of the lower incisor, which appears as an efficient morphology for piercing prey. The incisor of these mice also displays a reduced pulp cavity, suggesting slower eruption counterbalancing a reduced abrasion on such soft food material. The dynamics of the ever‐growing incisor may thus allow adaptive incisor sculpting and participate to the success of mice in foraging diverse resources. 相似文献
124.
Mariano Avino Garway T. Ng Yiying He Mathias S. Renaud Bradley R. Jones Art F. Y. Poon 《Ecology and evolution》2019,9(12):6756-6771
Cophylogeny is the congruence of phylogenetic relationships between two different groups of organisms due to their long‐term interaction. We investigated the use of tree shape distance measures to quantify the degree of cophylogeny. We implemented a reverse‐time simulation model of pathogen phylogenies within a fixed host tree, given cospeciation probability, host switching, and pathogen speciation rates. We used this model to evaluate 18 distance measures between host and pathogen trees including two kernel distances that we developed for labeled and unlabeled trees, which use branch lengths and accommodate different size trees. Finally, we used these measures to revisit published cophylogenetic studies, where authors described the observed associations as representing a high or low degree of cophylogeny. Our simulations demonstrated that some measures are more informative than others with respect to specific coevolution parameters especially when these did not assume extreme values. For real datasets, trees’ associations projection revealed clustering of high concordance studies suggesting that investigators are describing it in a consistent way. Our results support the hypothesis that measures can be useful for quantifying cophylogeny. This motivates their usage in the field of coevolution and supports the development of simulation‐based methods, i.e., approximate Bayesian computation, to estimate the underlying coevolutionary parameters. 相似文献
125.
Stphanie Sherpa Maya Guguen Julien Renaud Michael G. B. Blum Thierry Gaude Frdric Laporte Mustafa Akiner Bulent Alten Carles Aranda Hlne Barre‐Cardi Romeo Bellini Mikel Bengoa Paulis Xiao‐Guang Chen Roger Eritja Eleonora Flacio Cipriano Foxi Intan H. Ishak Katja Kalan Shinji Kasai Fabrizio Montarsi Igor Pajovi Duan Petri Rosa Termine Nataa Turi Gonzalo M. Vazquez‐Prokopec Enkelejda Velo Goran Vignjevi Xiaohong Zhou Laurence Desprs 《Ecology and evolution》2019,9(22):12658-12675
Invasive species can encounter environments different from their source populations, which may trigger rapid adaptive changes after introduction (niche shift hypothesis). To test this hypothesis, we investigated whether postintroduction evolution is correlated with contrasting environmental conditions between the European invasive and source ranges in the Asian tiger mosquito Aedes albopictus. The comparison of environmental niches occupied in European and source population ranges revealed more than 96% overlap between invasive and source niches, supporting niche conservatism. However, we found evidence for postintroduction genetic evolution by reanalyzing a published ddRADseq genomic dataset from 90 European invasive populations using genotype–environment association (GEA) methods and generalized dissimilarity modeling (GDM). Three loci, among which a putative heat‐shock protein, exhibited significant allelic turnover along the gradient of winter precipitation that could be associated with ongoing range expansion. Wing morphometric traits weakly correlated with environmental gradients within Europe, but wing size differed between invasive and source populations located in different climatic areas. Niche similarities between source and invasive ranges might have facilitated the establishment of populations. Nonetheless, we found evidence for environmental‐induced adaptive changes after introduction. The ability to rapidly evolve observed in invasive populations (genetic shift) together with a large proportion of unfilled potential suitable areas (80%) pave the way to further spread of Ae. albopictus in Europe. 相似文献
126.
Jean-Marc Bielser Jakub Domaradzki Jonathan Souquet Hervé Broly Massimo Morbidelli 《Biotechnology progress》2019,35(3):e2790
Perfusion cell culture, confined traditionally to the production of fragile molecules, is currently gaining broader attention in the biomanufacturing of therapeutic proteins. The development of these processes is made difficult by the limited availability of appropriate scale-down models. This is due to the continuous operation that requires complex control and cell retention capacity. For example, the determination of an optimal perfusion and bleed rate for continuous cell culture is often performed in scale-down bioreactors and requires a substantial amount of time and effort. To increase the experimental throughput and decrease the required workload, a semi-continuous procedure, referred to as the VCDmax (viable cell density) approach, has been developed on the basis of shake tubes (ST) and deepwell plates (96-DWP). Its effectiveness has been demonstrated for 12 different CHO-K1-SV cell lines expressing an IgG1. Further, its reliability has been investigated through proper comparisons with perfusion runs in lab-scale bioreactors. It was found that the volumetric productivity and the CSPRmin (cell specific perfusion rate) determined using the ST and 96-DWP models were successfully (mostly within the experimental error) confirmed in lab-scale bioreactors, which then covered a significant scale-up from the half milliliter to the liter scale. These scale-down models are very useful to design and scale-up optimal bioreactor operating conditions as well as screening for different media and cell lines. 相似文献
127.
128.
beta-Oxidation is a cyclic pathway involved in the degradation of lipids. In yeast, it occurs in peroxisomes and the first step is catalyzed by an acyl-CoA oxidase (Aoxp). The yeast Yarrowia lipolytica possesses several genes (POX) coding for Aoxps. This study is based on the factorial analysis of results obtained with the many POX derivative strains that have been constructed previously. The effect of interactions between Aoxps on the acyl-CoA oxidase (Aox) activity was important even at the second order. We then investigated the effect of Aox activity on growth and lactone production. Aox activity was correlated with acidification of the medium by cells and with cellular growth but not with lactone production, although Aox activity on short chains was inversely correlated with lactone accumulation. Due to the poor correlation between Aox activity and lactone production, the modeling of this parameter gave no satisfactory results but growth depending on Aox activity was modeled. 相似文献
129.
In the nucleus of eukaryotic cells, histone proteins organize the linear genome into a functional and hierarchical architecture. In this paper, we use the crystal structures of the nucleosome core particle, B-DNA and the globular domain of H5 linker histone to build the first all-atom model of compact chromatin fibers. In this 3D jigsaw puzzle, DNA bending is achieved by solving an inverse kinematics problem. Our model is based on recent electron microscopy measurements of reconstituted fiber dimensions. Strikingly, we find that the chromatin fiber containing linker histones is a polymorphic structure. We show that different fiber conformations are obtained by tuning the linker histone orientation at the nucleosomes entry/exit according to the nucleosomal repeat length. We propose that the observed in vivo quantization of nucleosomal repeat length could reflect nature's ability to use the DNA molecule's helical geometry in order to give chromatin versatile topological and mechanical properties. 相似文献
130.
Lefevre T Thomas F Schwartz A Levashina E Blandin S Brizard JP Le Bourligu L Demettre E Renaud F Biron DG 《Proteomics》2007,7(11):1908-1915
Despite increasing evidence of behavioural manipulation of their vectors by pathogens, the underlying mechanisms causing infected vectors to act in ways that benefit pathogen transmission remain enigmatic in most cases. Here, 2-D DIGE coupled with MS were employed to analyse and compare the head proteome of mosquitoes (Anopheles gambiae sensu stricto (Giles)) infected with the malarial parasite (Plasmodium berghei) with that of uninfected mosquitoes. This approach detected altered levels of 12 protein spots in the head of mosquitoes infected with sporozoites. These proteins were subsequently identified using MS and functionally classified as belonging to metabolic, synaptic, molecular chaperone, signalling, and cytoskeletal groups. Our results indicate an altered energy metabolism in the head of sporozoite-infected mosquitoes. Some of the up-/down-regulated proteins identified, such as synapse-associated protein, 14-3-3 protein and calmodulin, have previously been shown to play critical roles in the CNS of both invertebrates and vertebrates. Furthermore, a heat shock response (HSP 20) and a variation of cytoarchitecture (tropomyosins) have been shown. Discovery of these proteins sheds light on potential molecular mechanisms that underlie behavioural modifications and offers new insights into the study of intimate interactions between Plasmodium and its Anopheles vector. 相似文献