Publications by authors named "Obeso J"

Progressive loss of the ascending dopaminergic projection in the basal ganglia is a fundamental pathological feature of Parkinson's disease. Studies in animals and humans have identified spatially segregated functional territories in the basal ganglia for the control of goal-directed and habitual actions. In patients with Parkinson's disease the loss of dopamine is predominantly in the posterior putamen, a region of the basal ganglia associated with the control of habitual behaviour.

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The feedback of biodiversity on individual trait variation is a poorly explored mechanistic pathway in ecological research. We analysed the relationship between biodiversity and individual performance by focusing on vocal mimicry, a widespread interaction that may serve in intra- and interspecific communication. We studied the songs of two lark species (genus Galerida) that increase the complexity of their song displays by mimicking other birds, and analysed the influence of bird species richness on individual song performance.

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Functional stereotaxy was introduced in the late 1940s to reduce the morbidity of lobotomy in psychiatric disease by using more focal lesions. The advent of neuroleptics led to a drastic decline in psychosurgery for several decades. Functional stereotactic neurosurgery has recently been revitalized, starting with treatment of Parkinson's disease, in which deep brain stimulation (DBS) facilitates reversible focal neuromodulation of altered basal ganglia circuits.

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We present single photon emission computed tomography (SPECT) studies using 123IFP-CIT (DAT scan) and 123I-IBZM imaging, performed on four members of a family with genetically proven spinocerebellar ataxia type 3 (SCA-3). DAT scan showed significant asymmetric decreased binding in the striatum in the two members with predominant parkinsonian phenotype, with mild and symmetric decreased binding in the member with the cerebellar phenotype, and normal in the asymptomatic member. The IBZM SPECT studies showed mild and asymmetrical reduction of the striatal dopamine D2 receptor density (parkinsonian members).

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Objective: To investigate chaperone-mediated autophagy in the pathogenesis of Parkinson disease (PD).

Design: Postmortem observational study.

Setting: University Department of Clinical Neuroscience, Institute of Neurology, University College London.

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Melevodopa hydrochloride plus carbidopa in effervescent tablets (M/C) is a readily soluble antiparkinsonian tablet formulation. A total of 221 patients with Parkinson's disease and motor fluctuations entered a randomized, double-blind, double-dummy, controlled parallel group study, which compared the effectiveness of oral M/C effervescent tablets with standard oral formulation levodopa/carbidopa tablets (L/C; Sinemet) in reducing total daily OFF time. The difference of total daily OFF time (intention-to-treat population) between the two groups was not statistically significant (P = 0.

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The use of bacteriophages provides an attractive approach to the fight against food-borne pathogenic bacteria, since they can be found in different environments and are unable to infect humans, both characteristics of which support their use as biocontrol agents. Two lytic bacteriophages, vB_SauS-phiIPLA35 (phiIPLA35) and vB_SauS-phiIPLA88 (phiIPLA88), previously isolated from the dairy environment inhibited the growth of Staphylococcus aureus. To facilitate the successful application of both bacteriophages as biocontrol agents, probabilistic models for predicting S.

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Since the advent of deep brain stimulation (DBS) for the treatment of Parkinson's disease (PD), subsequent cognitive and neuropsychiatric effects of this procedure have become well-chronicled. Yet, thermolitic lesion of the subthalamic nucleus (STN) is still a valid option when DBS cannot be applied, and little has been published regarding its impact on cognition and mood. We examined the cognitive and neuropsychiatric functions of 10 consecutive patients with advanced PD undergoing simultaneous bilateral subthalamotomies.

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Parkinson's disease is a neurodegenerative process characterized by numerous motor and nonmotor clinical manifestations for which effective, mechanism-based treatments remain elusive. Here we discuss a series of critical issues that we think researchers need to address to stand a better chance of solving the different challenges posed by this pathology.

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In Parkinson's disease (PD), the oscillatory activity recorded from the basal ganglia shows dopamine-dependent changes. In the "off" parkinsonian motor state, there is prominent activity in the beta band (12-30 Hz) that is mostly attenuated after dopaminergic therapy ("on" medication state). The on state is also characterized by activity in the gamma (60-80 Hz) and high-frequency (300 Hz) bands that is modulated by movement.

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The current basal ganglia model considers the internal division of the globus pallidus and the substantia nigra pars reticulata as the sole sources of basal ganglia output to the thalamus. However, following the delivery of retrograde tracers into the ventral anterior/ventral lateral thalamic nuclei, a moderate number of labeled neurons were found within the subthalamic nucleus (STN) in control cases, MPTP-treated monkeys and animals with levodopa-induced dyskinesias. Furthermore, dual tracing experiments showed that subthalamo-thalamic and subthalamo-pallidal projections arise from different subpopulations of STN efferent neurons.

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Although levodopa provides therapeutic benefit over the entire course of Parkinson's disease, most patients eventually notice a decline in the duration of benefit from each dose, a phenomenon termed 'wearing-off' or 'end of dose' deterioration. This is an important indicator that the patient is entering a more complex phase of the disease. Wearing-off has been classically associated with the later stages of Parkinson's disease, but it is becoming apparent that patients with early disease, presenting as well controlled, may already be experiencing fluctuations in their response to levodopa.

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Unlabelled: Dopaminergic depletion in the nigrostriatal system is the neurochemical hallmark of Parkinson's disease (PD). Although numerous efforts have been made to determine the evolution of dopaminergic depletion in PD, "in vivo" data concerning the stages of this process are still scarce. We evaluated 6-[18F]-fluoro-l-DOPA ((18)F-DOPA) and 11C-(+)-alpha-dihydrotetrabenazine ((11)C-DTBZ) using PET in a model of chronically MPTP-induced parkinsonism in non-human primates.

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We report the 5 to 6 year follow-up of a multicenter study of bilateral subthalamic nucleus (STN) and globus pallidus internus (GPi) deep brain stimulation (DBS) in advanced Parkinson's disease (PD) patients. Thirty-five STN patients and 16 GPi patients were assessed at 5 to 6 years after DBS surgery. Primary outcome measure was the stimulation effect on the motor Unified Parkinson's Disease Rating Scale (UPDRS) assessed with a prospective cross-over double-blind assessment without medications (stimulation was randomly switched on or off).

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The ability of bone marrow cells (BMCs) to migrate to different organs can be used for indirect cell therapy, a procedure based on the engraftment of therapeutic cells in a different place from where they will finally move to and perform their action and which could be particularly useful for chronic illness where a persistent and long-lasting therapeutic action is required. Thus, establishing a stable colony of engineered BMCs is a requisite for the chronic provision of damaged tissues with engineered cells. Reported here is a procedure for creating such a cell colony in a portion of the bone marrow (BM).

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Objective: The observation of a voluntary movement executed by another person is associated with an alpha and beta EEG desynchronization over the motor cortex, thought to reflect activity from the human "mirror neuron" system. The aim of our work was to study the changes in local field potentials (LFP) recorded from the subthalamic nucleus (STN) and their relationship with cortical activity, during movement observation.

Methods: Bilateral EEG and STN LFP recordings were acquired in 18 patients with Parkinson's disease, through surgically implanted electrodes for deep brain stimulation.

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Cell-based therapies that involve transplantation into the striatum of dopaminergic cells have attracted considerable interest as possible treatments for Parkinson's disease (PD). However, all double-blind, sham-controlled, studies have failed to meet their primary endpoints, and transplantation of dopamine cells derived from the fetal mesencephalon is associated with a potentially disabling form of dyskinesia that persists even after withdrawal of levodopa (off-medication dyskinesia). In addition, disability in advanced patients primarily results from features such as gait dysfunction, freezing, falling, and dementia, which are likely due to nondopaminergic pathology.

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Dopamine is an essential neurotransmitter for many brain functions, and its dysfunction has been implicated in both neurological and psychiatric disorders. Parkinson's disease is an archetypal disorder of dopamine dysfunction characterised by motor, cognitive, behavioural, and autonomic symptoms. While effective for motor symptoms, dopamine replacement therapy is associated not only with motor side-effects, such as levodopa-induced dyskinesia, but also behavioural side-effects such as impulse control disorders (eg, pathological gambling and shopping, binge eating, and hypersexuality), punding (ie, abnormal repetitive non-goal oriented behaviours), and compulsive medication use.

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A dopaminergic deficiency in patients with Parkinson's disease (PD) causes abnormalities of movement, behaviour, learning, and emotions. The main motor features (ie, tremor, rigidity, and akinesia) are associated with a deficiency of dopamine in the posterior putamen and the motor circuit. Hypokinesia and bradykinesia might have a dual anatomo-functional basis: hypokinesia mediated by brainstem mechanisms and bradykinesia by cortical mechanisms.

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Background And Purpose: Linkage analysis in familial Parkinson's disease (PD) identified a locus in 2q36-37 (PARK11). Sequencing of GIGYF2 identified several variants only present amongst PD individuals.

Methods: We analyzed the presence of disease-associated GIGYF2 variants in familial and sporadic PD from Spanish origin by sequencing of 147 PD individuals.

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The genomes of the two lytic mutant Staphylococcus aureus bacteriophages, vB_SauS-phiIPLA35 (phiIPLA35) and vB_SauS-phiIPLA88 (phiIPLA88), isolated from milk have been analyzed. Their genomes are 45,344 bp and 42,526 bp long, respectively, and contain 62 and 61 open reading frames (ORFS). Enzymatic analyses and sequencing revealed that the phiIPLA35 DNA molecule has 3'-protruding cohesive ends (cos) 10 bp long, whereas phiIPLA88 DNA is 4.

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The diagnosis of Parkinson's disease (PD) is still based on the recognition of the cardinal motor features. However, it is now recognized that non-motor manifestations (NMM) may actually precede the emergence of motor manifestations. NMM are very frequently present in the overall population of PD patients and are a major determinant of their quality of life.

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Background: Dystonia is a complex clinical syndrome originated by a wide range of aetiologies. The diagnosis of dystonia is made after the evaluation of aetiological, phenomenological and genetic factors. Medications, except in patients with dopa-responsive dystonia, are of limited efficacy.

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