Publications by authors named "Sylvie Briand Schumacher"

The bacterial human pathogen Helicobacter pylori produces a type IV secretion system (cagT4SS) to inject the oncoprotein CagA into gastric cells. The cagT4SS external pilus mediates attachment of the apparatus to the target cell and the delivery of CagA. While the composition of the pilus is unclear, CagI is present at the surface of the bacterium and required for pilus formation.

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Background: Extracellular vesicles are released upon cellular activation and mediate inter-cellular communication. Individual species of extracellular vesicles might have divergent roles in vascular homeostasis and may show different responses to therapies such as exercise training.

Aims: We examine endothelial effects of medium-size and small extracellular vesicles from the same individual with or without chronic coronary syndrome, and in chronic coronary syndrome patients participating in a four-week high-intensity interval training intervention.

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Background and Purpose- Inflammation is a major pathogenic component of ischemia/reperfusion brain injury, and as such, interventions aimed at inhibiting inflammatory mediators promise to be effective strategies in stroke therapy. JunD-a member of the AP-1 (activated protein-1) family of transcription factors-was recently shown to regulate inflammation by targeting IL (interleukin)-1β synthesis and macrophage activation. The purpose of the present study was to assess the role of JunD in ischemia/reperfusion-induced brain injury.

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Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is implicated in cardiovascular disease by modulating apoptosis and oxidative stress. We hypothesized that LOX-1 may be involved in pathophysiology of stroke by mediating ischaemia/reperfusion (I/R)-dependent cell death. Transient middle cerebral artery occlusion (tMCAO) was performed in wild-type (WT) mice, endothelial-specific LOX-1 transgenic mice (eLOX-1TG) and WT animals treated with LOX-1 silencing RNA (siRNA).

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Background: In acute ischemic stroke (AIS) patients, impaired blood-brain barrier (BBB) integrity is associated with hemorrhagic transformation and worsened outcome. Yet, the mechanisms underlying these relationships are poorly understood and consequently therapeutic strategies are lacking. This study sought to determine whether SIRT5 contributes to BBB damage following I/R brain injury.

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Aims: MicroRNAs (miRNA) are important non-coding modulators controlling patterns of gene expression. However, profiling and validation of circulating miRNA levels related to adverse cardiovascular outcome has not been performed in patients with an acute coronary syndrome (ACS).

Methods And Results: In a multicentre, prospective ACS cohort, 1002 out of 2168 patients presented with ST-segment elevation myocardial infarction (STEMI).

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Cellular senescence, a programmed state induced by multiple deleterious triggers, is characterised by permanent cell-cycle exit and altered gene expression and cell morphology. In humans it is considered a tumor suppressor mechanism, mediating removal of damaged or mutated cells from the cell-cycle pool, and may also contribute to the ageing process. In this study, we show that senescent human umbilical vein endothelial cells lose their ability to induce tissue factor (TF), a transmembrane protein with important roles in hemostasis and cancer progression, in response to thrombin or - independently of cell-surface receptors - phorbol-12-myristate-13-acetate.

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The function of human XPA protein, a key subunit of the nucleotide excision repair pathway, has been examined with site-directed substitutions in its putative DNA-binding cleft. After screening for repair activity in a host-cell reactivation assay, we analyzed mutants by comparing their affinities for different substrate architectures, including DNA junctions that provide a surrogate for distorted reaction intermediates, and by testing their ability to recruit the downstream endonuclease partner. Normal repair proficiency was retained when XPA mutations abolished only the simple interaction with linear DNA molecules.

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Synthetic glucocorticoids belong to the most frequently administered drugs in livestock production. These synthetic hormones are employed for therapeutic purposes against inflammatory reactions, disorders of the musculoskeletal system, bovine ketosis and many other diseases of farm animals. A widespread illegal use of synthetic glucocorticoids to improve feed intake and weight gain has also been observed.

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