Publications by authors named "Posada I"

Introduction: Motor fluctuations are one of the most common complications of Parkinson's disease and their treatment is still a complex matter. Therefore, from the Neurology Movement Disorders Group we present our clinical experience in the treatment of these complications, with the intention of it being useful in decision-making in daily clinical practice.

Development: Nineteen questions were developed based on a literature review and an open survey answered by members of this group.

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Introduction: Both recessive and dominant genetic forms of Parkinson's disease have been described. The aim of this study was to assess the contribution of several genes to the pathophysiology of early onset Parkinson's disease in a cohort from central Spain.

Methods/patients: We analyzed a cohort of 117 unrelated patients with early onset Parkinson's disease using a pipeline, based on a combination of a next-generation sequencing panel of 17 genes previously related with Parkinson's disease and other Parkinsonisms and CNV screening.

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Objective: Although the cerebello-thalamo-cortical network has often been suggested to be of importance in the pathogenesis of essential tremor (ET), the origins of tremorgenic activity in this disease are not fully understood. We used a combination of cortical thickness imaging and neurophysiological studies to analyze whether the severity of tremor was associated with anatomical changes in the brain in ET patients

Methods: Magnetic resonance imaging (MRI) and a neurophysiological assessment were performed in 13 nondemented ET patients. High field structural brain MRI images acquired in a 3T scanner and analyses of cortical thickness and surface were carried out.

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There remains much to learn about the changes in cortical anatomy that are associated with tremor severity in Parkinson's disease (PD). For this reason, we used a combination of structural neuroimaging to measure cortical thickness and neurophysiological studies to analyze whether PD tremor was associated with cortex integrity. Magnetic resonance imaging and neurophysiological assessment were performed in 13 nondemented PD patients (9 women, 69.

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Introduction: Botulinum toxin type A (BTA) is a bacterial endotoxin, whose therapeutic use has had a dramatic impact on different neurological disorders, such as dystonia and spasticity.

Aim: To analyze and summarize different questions about the use of BTA in our clinical practice.

Development: A group of experts in neurology developed a list of topics related with the use of BTA.

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As a major growth factor transducer, Ras is an upstream activator of mTORC1, which further integrates nutrient and energy inputs. To ensure a contextual coupling of cell division via Ras/MAPK-signalling and growth via mTORC1-signalling, feedback loops from one pathway back to the other are required. Here we describe a novel feedback from mTORC1, which oppositely affects oncogenic H-ras- and K-ras-signalling output, and as a consequence stemness properties of tumourigenic cells.

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Currently several combination treatments of mTor- and Ras-pathway inhibitors are being tested in cancer therapy. While multiple feedback loops render these central signaling pathways robust, they complicate drug targeting.Here, we describe a novel H-ras specific feedback, which leads to an inadvertent rapalog induced activation of tumorigenicity in Ras transformed cells.

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Ras-induced senescence mediated through ASPP2 represents a barrier to tumour formation. It is initiated by ASPP2's interaction with Ras at the plasma membrane, which stimulates the Raf/MEK/ERK signaling cascade. Ras to Raf signalling requires Ras to be organized in nanoscale signalling complexes, called nanocluster.

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Introduction: Although antidepressants are widely used in Parkinson's disease (PD), few well-designed studies to support their efficacy have been conducted.

Development: These clinical guidelines are based on a review of the literature and the results of an AMN movement disorder study group survey.

Conclusions: Evidence suggests that nortriptyline, venlafaxine, paroxetine, and citalopram may be useful in treating depression in PD, although studies on paroxetine and citalopram yield conflicting results.

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Cancer stem cells (CSCs) are considered to be responsible for treatment relapse and have therefore become a major target in cancer research. Salinomycin is the most established CSC inhibitor. However, its primary mechanistic target is still unclear, impeding the discovery of compounds with similar anti-CSC activity.

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Essential tremor (ET) has been associated with a spectrum of clinical features, with both motor and nonmotor elements, including cognitive deficits. We employed resting-state functional magnetic resonance imaging (fMRI) to assess whether brain networks that might be involved in the pathogenesis of nonmotor manifestations associated with ET are altered, and the relationship between abnormal connectivity and ET severity and neuropsychological function.Resting-state fMRI data in 23 ET patients (12 women and 11 men) and 22 healthy controls (HC) (12 women and 10 men) were analyzed using independent component analysis, in combination with a "dual-regression" technique, to identify the group differences of resting-state networks (RSNs) (default mode network [DMN] and executive, frontoparietal, sensorimotor, cerebellar, auditory/language, and visual networks).

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Ras isoforms H-, N-, and K-ras are each mutated in specific cancer types at varying frequencies and have different activities in cell fate control. On the plasma membrane, Ras proteins are laterally segregated into isoform-specific nanoscale signaling hubs, termed nanoclusters. As Ras nanoclusters are required for Ras signaling, chemical modulators of nanoclusters represent ideal candidates for the specific modulation of Ras activity in cancer drug development.

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Rab proteins constitute the largest subfamily of Ras-like small GTPases. They are central to vesicular transport and organelle definition in eukaryotic cells. Unlike their Ras counterparts, they are not a hallmark of cancer.

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Nonmotor symptoms (NMS) in Parkinson's disease (PD) can precede onset of motor symptoms. Relationship between premotor symptoms onset and motor features is limited. Our aim is to describe the presence and perceived onset of NMS in PD as well as their possible association with motor phenotype.

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Article Synopsis
  • Human phospholipid scramblase 1 (SCR) facilitates the movement of phospholipids across membranes and is thought to interact with the membrane's hydrophobic core through its transmembrane domain and palmitoyl groups.
  • Recent research investigates how the SCR's transmembrane domain interacts with cholesterol, revealing a specific region at the C-terminal that has a strong affinity for cholesterol despite not having the typical CRAC sequence.
  • This cholesterol-binding region is partly located within the C-terminal part of the transmembrane domain and the initial amino acids of the SCR's C-terminal extracellular region, which may explain its preference for cholesterol-rich membrane areas.
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Human phospholipid scramblase 1 (SCR) consists of a large cytoplasmic domain and a small presumed transmembrane domain near the C-terminal end of the protein. Previous studies with the SCRΔ mutant lacking the C-terminal portion (last 28 aa) revealed the importance of this C-terminal moiety for protein function and calcium-binding affinity. The present contribution is intended to elucidate the effect of the transmembrane domain suppression on SCRΔ binding to model membranes (lipid monolayers and bilayers) and on SCRΔ reconstitution in proteoliposomes.

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Background: Our aim was to assess the diagnostic agreement among the neurologists in the Neurological Disorders in Central Spain 2 (NEDICES-2) study; these neurologists were assigning diagnoses of essential tremor (ET) vs. no ET.

Methods: Clinical histories and standardized video-taped neurological examinations of 26 individuals (11 ET, seven Parkinson's disease, three diagnostically unclear, four normal, one with a tremor disorder other than ET) were provided to seven consultant neurologists, six neurology residents, and five neurology research fellows (18 neurologists total).

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Human phospholipid scramblase 1 (SCR) is a 318 amino acid protein that was originally described as catalyzing phospholipid transbilayer (flip-flop) motion in plasma membranes in a Ca²⁺-dependent, ATP-independent way. Further studies have suggested an intranuclear role for this protein in addition. A putative transmembrane domain located at the C terminus (aa 291-309) has been related to the flip-flop catalysis.

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Human phospholipid scramblase 1 (SCR) was originally described as an intrinsic membrane protein catalyzing transbilayer phospholipid transfer in the absence of ATP. More recently, a role as a nuclear transcription factor has been proposed for SCR, either in addition or alternatively to its capacity to facilitate phospholipid flip-flop. Uncertainties exist as well from the structural point of view.

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Hemifacial spasm (HFS) is usually produced by compression of the facial nerve by tortuous blood vessels at the root exit zone, including vertebrobasilar dolichoectasia (VBD). Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder with a variety of symptoms, affecting mainly the skin and nervous system. Cerebrovascular abnormalities are becoming a recognized complication of the disease and the most constantly described lesions are stenosis and occlusions affecting the internal carotid artery.

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Most studies of mortality in Parkinson's disease have been clinical studies, yielding results that are not representative of the general population. We assessed the risk of mortality from Parkinson's disease in the Neurological Disorders in Central Spain (NEDICES) study, a prospective population-based study in which Parkinson's disease patients who were not ascertained through medical practitioners were also included. The cohort consisted of 5262 elderly subjects (mean baseline age, 73.

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Background: Population-based assessments of cognitive function in patients with early Parkinson's disease (PD) are rare. We examined whether patients with early PD have cognitive deficits when compared with matched controls

Methods: All participants were age 65 years or older (median=76 years) and were enrolled in the Neurological Disorders in Central Spain (NEDICES) study in central Spain. We identified all participants with early PD (<5 years duration) (N=46).

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To evaluate the mortality, thirteen years after the baseline wave (1994), of participants suffering dementia in the Neurological Disorders in Central Spain (NEDICES) Cohort Study, we conducted a population-based cohort study in the elderly (65 years and more) with 5,278 screened participants at baseline. Mortality has been evaluated by means of the National Death Registry of Spain at 1-5-2007, 13 years after enrolment. Cox's proportional hazards regression models were used to evaluate the hazard of death according to dementia severity and type, adjusting for potential covariates (gender, age, level of education, and co-morbidity).

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