Martin Schain

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BACKGROUND Progressive supranuclear palsy (PSP) is difficult to diagnose accurately. The recently developed tau PET tracers may improve the diagnostic work-up of PSP. METHODS Regional tau accumulation was studied using 18 F-AV-1451 PET in 11 patients with PSP and 11 age-matched healthy controls in the Swedish BioFinder study. RESULTS 18 F-AV-1451(More)
BACKGROUNDS AND PURPOSE The main objectives of the present study were (i) to measure density changes of activated microglia and the peripheral benzodiazepine receptor/translocator protein (TSPO) system during normal ageing in the human brain with positron emission tomography (PET) using the TSPO molecular imaging biomarker [(11)C]vinpocetine and (ii) to(More)
Changes in P-glycoprotein and ABCG2 densities may play a role in amyloid-beta accumulation in Alzheimer's disease. However, previous studies report conflicting results from different brain regions, without correcting for changes in vessel density. We developed an automated method to measure transporter density exclusively within the vascular space, thereby(More)
Although there is increasing evidence for microglial activation after an ischaemic stroke in the infarct core and the peri-infarct region, the "evolution" of the process in stroke patients is poorly known. Using PET and [((11))C]vinpocetine, we measured the regional changes of TSPO in the brain of nine ischaemic stroke patients up to 14weeks after the(More)
The serotonin system is involved in many physiological functions and clinical conditions. Serotonergic neurons originate from the raphe nuclei in the brainstem, and reliable estimates of receptor/transporter availability in the raphe in vivo are thus of interest. Though positron emission tomography (PET) can be used to quantify receptor distribution in the(More)
Manual definition of regions of interest (ROIs) has been considered the reference standard method in PET data evaluation. The method is labor-intensive, prone to rater bias and may show low reproducibility. Automated template-based methods for ROI definition may overcome these limitations. The aim of this study was to validate the two automated methods(More)
[11C]AZ10419369 is a recently developed 5-HT1B receptor radioligand that is sensitive to changes in endogenous serotonin concentrations in the primate brain. Thus, [11C] AZ10419369 may serve as a useful tool in clinical studies of the pathophysiology and pharmacological treatment of diseases related to the serotonin system, such as depression and anxiety(More)
A metabolite corrected arterial input function is a prerequisite for quantification of positron emission tomography (PET) data by compartmental analysis. This quantitative approach is also necessary for radioligands without suitable reference regions in brain. The measurement is laborious and requires cannulation of a peripheral artery, a procedure that can(More)
UNLABELLED The High Resolution Research Tomograph (HRRT) is the PET system providing the highest resolution for imaging of the human brain. In this study, the improved quantitative performance of the HRRT was evaluated in comparison with a previously developed lower resolution PET system, the ECAT HR. The radioligand [(11)C]MADAM was chosen for the purpose(More)
The mammalian circadian clock underlies both diurnal and seasonal changes in physiology, and its function is thought to be disturbed in both seasonal and non-seasonal depression. In humans, molecular imaging studies have reported seasonal changes in the serotonin system. Despite the role of the circadian clock in generating seasonal physiological changes,(More)