Publications by authors named "Valerie Jeanneret"

Objectives: To report a case of a patient with overlapping posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS), and review the existing literature emphasizing the pathophysiological overlap of these two entities.

Materials And Methods: We conducted a literature search in electronic database PubMed identifying studies reporting the overlap of PRES and RCVS.

Results: PRES and RCVS are two increasingly recognized entities that share similar clinical and imaging features.

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A 55-year-old woman presented with recurrent episodes of headache, vision changes, and language disturbances. Brain MRI showed multifocal white matter lesions, microhemorrhages, and enlarged perivascular spaces. After an extensive and unrevealing workup, she underwent a biopsy of brain and meninges that revealed thick and hyalinized leptomeningeal and cortical vessel walls that were strongly positive for β-amyloid by immunohistochemical staining, suggestive of cerebral amyloid angiopathy (CAA).

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A wide number of neurological manifestations have been described in association with coronavirus disease 19 (COVID-19). We describe an unusual case of a young man who developed severe rhombencephalitis after COVID-19. He demonstrated clinical and radiological improvement with high dose corticosteroids, plasma exchange and intravenous immune globulin.

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Purpose: Studies examining seizures (Szs) and epileptiform abnormalities (EAs) using continuous EEG in acute ischemic stroke (AIS) are limited. Therefore, we aimed to describe the prevalence of Sz and EA in AIS, its impact on anti-Sz drug management, and association with discharge outcomes.

Methods: The study included 132 patients with AIS who underwent continuous EEG monitoring >6 hours.

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Neuronal depolarization induces the synaptic release of tissue-type plasminogen activator (tPA). Cyclin-dependent kinase-5 (Cdk5) is a member of the family of cyclin-dependent kinases that regulates cell migration and synaptic function in postmitotic neurons. Cdk5 is activated by its binding to p35 (also known as Cdk5r1), a membrane-anchored protein that is rapidly degraded by the proteasome.

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Cerebral ischemia causes the presynaptic release of tissue-type plasminogen activator (tPA). The postsynaptic density (PSD) is a postsynaptic structure that provides a matrix where signaling transduction of excitatory synapses takes place. The postsynaptic density protein-95 (PSD-95) is the most abundant scaffolding protein in the postsynaptic density (PSD), where it modulates the postsynaptic response to the presynaptic release of glutamate by regulating the anchoring of glutamate receptors to the PSD.

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Urokinase-type plasminogen activator (uPA) is a serine proteinase that, upon binding to its receptor (uPAR), catalyzes the conversion of plasminogen into plasmin on the cell surface. Our previous studies indicate that uPA and uPAR expression increase in the ischemic brain during the recovery phase from an acute ischemic injury and that uPA binding to uPAR promotes neurological recovery after an acute ischemic stroke. Here, we used male mice genetically deficient on either uPA (uPA) or uPAR (uPAR) or with a four-amino acid substitution into the growth factor domain of uPA that abrogates its binding to uPAR () to investigate the mechanism whereby uPA promotes neurorepair in the ischemic brain.

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Membrane depolarization induces the release of the serine proteinase tissue-type plasminogen activator (tPA) from the presynaptic terminal of cerebral cortical neurons. Once in the synaptic cleft this tPA promotes the exocytosis and subsequent endocytic retrieval of glutamate-containing synaptic vesicles, and regulates the postsynaptic response to the presynaptic release of glutamate. Indeed, tPA has a bidirectional effect on the composition of the postsynaptic density (PSD) that does not require plasmin generation or the presynaptic release of glutamate, but varies according to the baseline level of neuronal activity.

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Axonal injury is a common cause of neurological dysfunction. Unfortunately, in contrast to axons from the peripheral nervous system, the limited capacity of regeneration of central nervous system (CNS) axons is a major obstacle for functional recovery in patients suffering neurological diseases that involve the subcortical white matter. Urokinase-type plasminogen activator (uPA) is a serine proteinase that upon binding to the urokinase-type plasminogen activator receptor (uPAR) catalyzes the conversion of plasminogen into plasmin on the cell surface.

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Tissue-type plasminogen activator (tPA) is a serine proteinase released by the presynaptic terminal of cerebral cortical neurons following membrane depolarization (Echeverry et al., 2010). Recent studies indicate that the release of tPA triggers the synaptic vesicle cycle and promotes the exocytosis (Wu et al.

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Advances in neurocritical care and interventional neuroradiology have led to a significant decrease in acute ischemic stroke (AIS) mortality. In contrast, due to the lack of an effective therapeutic strategy to promote neuronal recovery among AIS survivors, cerebral ischemia is still a leading cause of disability in the world. Ischemic stroke has a harmful impact on synaptic structure and function, and plasticity-mediated synaptic recovery is associated with neurological improvement following an AIS.

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Background: Ultraviolet light exposure has a pathogenic effect on the development of skin cancer, whose prevalence increases worldwide. In Chile and the rest of the world, preventive educational campaigns are carried out to change high risk sun exposure behaviors.

Aim: To study the behavior of the Chilean population towards skin cancer prevention and to identify erroneous preventive practices and concepts.

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Angiotensin Converting Enzyme (ACE) or Kininase II has a pivotal role determining the local activity of the renin angiotensin and kallikrein kinin systems. Angiotensin II (Ang II), a main hormone of the renin system, has a well established participation as a renal injury agent in models of renal disease with tubulointerstitial fibrosis. Although, since its discovery, ACE has been known to convert Ang I to Ang II, and to inactivate bradykinin (BK), only recently has been emerged evidence for a role of BK with renal protective and antifibrotic effects opposing Ang II.

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