Publications by authors named "Olaf Bjarne Paulson"

Low-grade systemic inflammation contributes to ageing-related cognitive decline, possibly by triggering a neuroinflammatory response through glial activation. Using proton magnetic resonance spectroscopy ( H-MRS) at 7T in normal human individuals from 18 to 79 years in a cross-sectional study, we previously observed higher regional levels of myo-inositol (mIns), total creatine (tCr) and total choline (tCho) in older than younger age groups. Moreover, visuo-spatial working memory (vsWM) correlated negatively with tCr and tCho in anterior cingulate cortex (ACC) and mIns in hippocampus and thalamus.

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Proton MR spectroscopy (H-MRS) has been used to assess regional neurochemical brain changes during normal ageing, but results have varied. Exploiting the increased sensitivity at ultra-high field, we performed H-MRS in 60 healthy human volunteers to asses age-related differences in metabolite levels and their relation to cognitive ageing. Sex was balanced, and participants were assigned to a younger, middle, and older group according to their age, ranging from 18 to 79 years.

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After publication of the original article [1], the authors have notified us that an updated version of Figures 1, 2 and 3 should have been published. The incorrect and revised figures can be found below.

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Background: Sildenafil and calcitonin gene-related peptide both dilate the intradural segments of the middle meningeal artery measured with 3.0 tesla (T) MR angiography. Here we hypothesized that an increase in field strength to 7.

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Background: Sildenafil and calcitonin gene-related peptide are vasoactive substances that induce migraine attacks in patients. The intradural arteries are thought to be involved, but these have never been examined in vivo. Sildenafil is the only migraine-inducing compound for which cephalic, extracranial artery dilation is not reported.

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Article Synopsis
  • This study investigates how headache-inducing drugs like sildenafil and CGRP affect glutamate levels in the brainstem and thalamus, areas that may be significant in migraine research.
  • Using a specialized MRS protocol, 17 healthy participants were tested to observe glutamate changes after drug administration.
  • Results showed a temporary increase in glutamate levels in the brainstem after sildenafil but no changes from CGRP, indicating that CGRP might trigger headaches by affecting peripheral pain pathways instead.
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This study aims at developing a simulation system that predicts the optimal study design for attaining tracer steady-state conditions in brain and blood rapidly. Tracer kinetics was determined from bolus studies and used to construct the system. Subsequently, the system was used to design inputs for bolus infusion (BI) or programmed infusion (PI) experiments.

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Objective: To evaluate the prognostic value of the cortical N-acetyl aspartate to creatine ratio (NAA/Cr) in early relapsing-remitting multiple sclerosis (RRMS).

Methods: Sixteen patients with newly diagnosed RRMS were studied by serial MRI and MR spectroscopic imaging (MRSI) once every 6 months for 24 months. Clinical examinations, including the expanded disability status scale (EDSS), were performed at baseline, month 24, and at year 7.

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Resting-state functional magnetic resonance imaging (rs-fMRI) has been used to study changes in long-range functional brain connectivity in multiple sclerosis (MS). Yet little is known about how MS affects functional brain connectivity at the local level. Here we studied 42 patients with MS and 30 matched healthy controls with whole-brain rs-fMRI at 3 T to examine local functional connectivity.

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The adult visual cortex maintains a substantial potential for plasticity in response to a change in visual input. For instance, transcranial magnetic stimulation (TMS) studies have shown that binocular deprivation (BD) increases the cortical excitability for inducing phosphenes with TMS. Here, we employed TMS to trace plastic changes in adult visual cortex before, during, and after 48 h of monocular deprivation (MD) of the right dominant eye.

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