234 research outputs found
Incertitude et stratégies de (sur)vie
Au xviiie siĂšcle, lâembarquement des marins signifiait, pour les Ă©pouses restĂ©es Ă terre, une pĂ©riode de solitude dont la durĂ©e, variable selon le type dâembarquement, pouvait se chiffrer en mois voire en annĂ©es. Une trĂšs grande incertitude rĂ©gnait quant Ă la date du retour, surtout en temps de guerre. Les femmes de partis en mer, la fois vulnĂ©rables et convoitĂ©es, dĂ©veloppaient, pour faire face Ă cette situation souvent inconfortable, des stratĂ©gies dâadaptation axĂ©es sur la quĂȘte de ressources complĂ©mentaires. Lâendettement, la pluriactivitĂ©, la mobilisation des rĂ©seaux de solidaritĂ© constituaient les rĂ©ponses habituelles aux difficultĂ©s inhĂ©rentes Ă cet Ă©tat de solitude prolongĂ©e.During the 18th Century, sailors left their wives alone during periods that could last months or years, depending on the type of sailing. The date of their return was always very uncertain, especially in wartime. The sailorsâ wives, vulnerable and lusted after, suffered economic hardships and had to seek supplementary resources. Debt, pluriactivity, the mobilization of local solidarities, especially among women, were the most common response to this situation of prolonged loneliness
Dictionnaire de la mer et des cĂŽtes
Il est rare quâun ouvrage de gĂ©ographie fasse lâobjet dâune recension dans les Annales de Bretagne et des Pays de lâOuestâ; on se souvient quâen 1995, Alain Croix et Nicole Croix-Bedos avaient Ă©crit une « note critique » Ă propos de GĂ©ographie et amĂ©nagement de la Bretagne, publiĂ© en 1994 aux Ăditions Skol Vreizh sous la direction de Pierre-Yves Le Rhun et Jean-RenĂ© Le QuĂ©au. PrĂšs de vingt ans plus tard, le compte-rendu dâun nouvel ouvrage sâimpose, celui du Dictionnaire de la mer et des cĂŽte..
Functional Diversity of AAA+ Protease Complexes in Bacillus subtilis
Here, we review the diverse roles and functions of AAA+ protease complexes in protein homeostasis, control of stress response and cellular development pathways by regulatory and general proteolysis in the Gram-positive model organism Bacillus subtilis. We discuss in detail the intricate involvement of AAA+ protein complexes in controlling sporulation, the heat shock response and the role of adaptor proteins in these processes. The investigation of these protein complexes and their adaptor proteins has revealed their relevance for Gram-positive pathogens and their potential as targets for new antibiotics
Control of membrane barrier during bacterial type-III protein secretion
Type-III secretion systems (T3SSs) of the bacterial flagellum and the evolutionarily related injectisome are capable of translocating proteins with a remarkable speed of several thousand amino acids per second. Here, we investigate how T3SSs are able to transport proteins at such a high rate while preventing the leakage of small molecules. Our mutational and evolutionary analyses demonstrate that an ensemble of conserved methionine residues at the cytoplasmic side of the T3SS channel create a deformable gasket (M-gasket) around fast-moving substrates undergoing export. The unique physicochemical features of the M-gasket are crucial to preserve the membrane barrier, to accommodate local conformational changes during active secretion, and to maintain stability of the secretion pore in cooperation with a plug domain (R-plug) and a network of salt-bridges. The conservation of the M-gasket, R-plug, and salt-bridge network suggests a universal mechanism by which the membrane integrity is maintained during high-speed protein translocation in all T3SSs.Peer Reviewe
Controlling membrane barrier during bacterial type-III protein secretion
Type-III secretion systems (T3SSs) of the bacterial flagellum and the evolutionarily related injectisome are capable of translocating proteins with a remarkable speed of several thousand amino acids per second. Here, we investigated how T3SSs are able to transport proteins at such a high rate while preventing the leakage of small molecules. Our mutational and evolutionary analyses demonstrate that an ensemble of conserved methionine residues at the cytoplasmic side of the T3SS channel create a deformable gasket (M-gasket) around fast-moving substrates undergoing export. The unique physicochemical features of the M-gasket are crucial to preserve the membrane barrier, to accommodate local conformational changes during active secretion, and to maintain stability of the secretion pore in cooperation with a plug domain (R-plug) and a network of salt-bridges. The conservation of the M-gasket, R-plug, and salt-bridge network suggests a universal mechanism by which the membrane integrity is maintained during high-speed protein translocation in all T3SSs
Report of depressive symptoms on waiting list and mortality after liver and kidney transplantation: a prospective cohort study
International audienceABSTRACT: BACKGROUND: Little research has explored pre-transplantation psychological factors as predictors of outcome after liver or kidney transplantation. Our objective is to determine whether report of depressive symptoms on waiting list predicts outcome of liver and kidney transplantation. METHODS: Patients on waiting list for liver or kidney transplantation were classified for report or non-report of depressive symptoms on waiting list. 339 were transplanted 6 months later on average, and followed prospectively. The main outcome measures were graft failure and mortality 18 months post-transplantation. RESULTS: Among the 339 patients, 51.6% reported depressive symptoms on waiting list, 16.5% had a graft failure and 7.4% died post-transplantation. Report of depressive symptoms on waiting list predicted a 3 to 4-fold decreased risk of graft failure and mortality 18-months post-transplantation, independently from age, gender, current cigarette smoking, anxiety symptoms, main primary diagnosis, UNOS score, number of comorbid diagnoses and history of transplantation. Data were consistent for liver and kidney transplantations. Other baseline predictive factors were: for graft failure, the main primary diagnosis and a shorter length since this diagnosis, and for mortality, older age, male gender and the main primary diagnosis. CONCLUSION: Further studies are needed to understand the underlying mechanisms of the association between report of depressive symptoms on waiting list and decreased risk of graft failure and mortality after transplantation
The Dark Side of the Salad: Salmonella typhimurium Overcomes the Innate Immune Response of Arabidopsis thaliana and Shows an Endopathogenic Lifestyle
Salmonella enterica serovar typhimurium contaminated vegetables and fruits are considerable sources of human infections. Bacteria present in raw plant-derived nutrients cause salmonellosis, the world wide most spread food poisoning. This facultative endopathogen enters and replicates in host cells and actively suppresses host immune responses. Although Salmonella survives on plants, the underlying bacterial infection mechanisms are only poorly understood. In this report we investigated the possibility to use Arabidopsis thaliana as a genetically tractable host system to study Salmonella-plant interactions. Using green fluorescent protein (GFP) marked bacteria, we show here that Salmonella can infect various Arabidopsis tissues and proliferate in intracelullar cellular compartments. Salmonella infection of Arabidopsis cells can occur via intact shoot or root tissues resulting in wilting, chlorosis and eventually death of the infected organs. Arabidopsis reacts to Salmonella by inducing the activation of mitogen-activated protein kinase (MAPK) cascades and enhanced expression of pathogenesis related (PR) genes. The induction of defense responses fails in plants that are compromised in ethylene or jasmonic acid signaling or in the MKK3-MPK6 MAPK pathway. These findings demonstrate that Arabidopsis represents a true host system for Salmonella, offering unique possibilities to study the interaction of this human pathogen with plants at the molecular level for developing novel drug targets and addressing current safety issues in human nutrition
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