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This article reviews neuronal activity related to reward processing in primate and human brains. In the primate brain, neurophysiological methods provide a differentiated view of reward processing in a limited number of brain structures. Dopamine neurons respond to unpredictable rewards and produce a global reinforcement signal. Some neurons in the striatum(More)
Regional cerebral blood flow (rCBF) in healthy controls and non-demented, non-depressed Parkinsonian patients was measured using H2(15)O PET while subjects performed a prelearned pattern recognition task with delayed response. To investigate differences between the two groups in response to reward, the experimental design consisted of three reinforcement(More)
OBJECTIVES Botulinum toxin injections have become a first line therapeutic approach in cervical dystonia. Nevertheless, published dosing schedules, responder rates, and frequency of adverse events vary widely. The present prospective multicentre placebo controlled double blind dose ranging study was performed in a homogenous group of previously untreated(More)
The coordinated orientation of ciliary beat in the larval epidermis of amphibians, evident in an organized streamline pattern, suggests a planar polarity of the epithelium, i.e., a polarity within the plane of the cell sheet. It has been proposed that the direction of ciliary beat is determined at mid gastrula by a gradient of a diffusible factor produced(More)
Investigations of the marine-derived fungus Monodictys putredinis led to the isolation of two novel dimeric chromanones (1, 2) that consist of two uniquely modified xanthone-derived units. The structures were elucidated by extensive spectroscopic measurements including NOE experiments and CD analysis to deduce the configuration. The compounds (1, 2) were(More)
Investigation of the fungal strain Monodictys putredinis isolated from the inner tissue of a marine green alga led to the isolation of four new monomeric xanthones and a benzophenone. All structures were elucidated by extensive spectroscopic measurements. The relative configuration of compound 1 was determined by X-ray crystal structure analysis, while for(More)
Investigation of the fungus Phaeosphaeria spartinae, an endophyte of the marine red alga Ceramium sp., led to the isolation of spartopregnenolone (1), a metabolite whose structure includes features of triterpenes and steroids, i.e. a Δ(8,9) double bond as occurring in lanosterol type triterpenoids, a carboxyl group at C-4 which is characteristic for(More)
It is not yet established whether oxidative stress is a major cause of cell death or simply a consequence of an unknown pathogenetic factor. Concerning chronic diseases, as Parkinson's and Alzheimer's disease are assumed to be, it is possible that a gradual impairment of cellular defense mechanisms leads to cell damage because of toxic substances being(More)
Tobacco smoking is the most frequent form of substance abuse. Several studies have shown that the addictive action of nicotine is mediated by the mesolimbic dopamine system. This system is implicated in reward processing. In order to better understand the relationship between nicotine addiction and reward in humans, we investigated differences between(More)
A four- to fivefold overexpression of the gene for the Alzheimer beta/A4 amyloid precursor protein (APP) in individuals with Down's Syndrome (DS) appears to be responsible for the fifty year earlier onset of Alzheimer's disease (AD) pathology in DS compared to the normal population. It is therefore likely that a deregulated overexpression of the APP gene is(More)