Publications by authors named "Julia Reinhardt"

35 Publications

Oral insulin immunotherapy in children at risk for type 1 diabetes in a randomised controlled trial.

Diabetologia 2021 Jan 30. Epub 2021 Jan 30.

Institute of Diabetes Research, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany.

Aims/hypothesis: Oral administration of antigen can induce immunological tolerance. Insulin is a key autoantigen in childhood type 1 diabetes. Here, oral insulin was given as antigen-specific immunotherapy before the onset of autoimmunity in children from age 6 months to assess its safety and immune response actions on immunity and the gut microbiome.

Methods: A phase I/II randomised controlled trial was performed in a single clinical study centre in Germany. Participants were 44 islet autoantibody-negative children aged 6 months to 2.99 years who had a first-degree relative with type 1 diabetes and a susceptible HLA DR4-DQ8-containing genotype. Children were randomised 1:1 to daily oral insulin (7.5 mg with dose escalation to 67.5 mg) or placebo for 12 months using a web-based computer system. The primary outcome was immune efficacy pre-specified as induction of antibody or T cell responses to insulin and measured in a central treatment-blinded laboratory.

Results: Randomisation was performed in 44 children. One child in the placebo group was withdrawn after the first study visit and data from 22 insulin-treated and 21 placebo-treated children were analysed. Oral insulin was well tolerated with no changes in metabolic variables. Immune responses to insulin were observed in children who received both insulin (54.5%) and placebo (66.7%), and the trial did not demonstrate an effect on its primary outcome (p = 0.54). In exploratory analyses, there was preliminary evidence that the immune response and gut microbiome were modified by the INS genotype Among children with the type 1 diabetes-susceptible INS genotype (n = 22), antibody responses to insulin were more frequent in insulin-treated (72.7%) as compared with placebo-treated children (18.2%; p = 0.03). T cell responses to insulin were modified by treatment-independent inflammatory episodes.

Conclusions/interpretation: The study demonstrated that oral insulin immunotherapy in young genetically at-risk children was safe, but was not associated with an immune response as predefined in the trial primary outcome. Exploratory analyses suggested that antibody responses to oral insulin may occur in children with a susceptible INS genotype, and that inflammatory episodes may promote the activation of insulin-responsive T cells.

Trial Registration: Clinicaltrials.gov NCT02547519 FUNDING: The main funding source was the German Center for Diabetes Research (DZD e.V.).
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http://dx.doi.org/10.1007/s00125-020-05376-1DOI Listing
January 2021

Cats and Apples: Semantic Fluency Performance for Living Things Identifies Patients with Very Early Alzheimer's Disease.

Arch Clin Neuropsychol 2020 Nov 25. Epub 2020 Nov 25.

Faculty of Psychology, University of Basel, Basel, Switzerland.

Objective: Reduced semantic memory performance is a known neuropsychological marker of very early Alzheimer's disease (AD), but the task format that best predicts disease status is an open question. The present study aimed to identify the semantic fluency task and measure that best discriminates early-stage AD patients (PATs) from cognitively healthy controls.

Method: Semantic fluency performance for animals, fruits, tools, and vehicles was assessed in 70 early-stage AD PATs and 67 cognitively healthy participants. Logistic regressions and receiver operating characteristics were calculated for five total score semantic fluency measures.

Results: Compared with all other measures, living things (i.e., total correct animals + total correct fruits) achieved highest z-statistics, highest area under the curve and smallest difference between the upper and lower 95% confidence intervals.

Conclusion: Living things total correct is a powerful tool to detect the earliest signs of incipient AD.
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http://dx.doi.org/10.1093/arclin/acaa109DOI Listing
November 2020

Neural Correlates of Stepping in Healthy Elderly: Parietal and Prefrontal Cortex Activation Reflects Cognitive-Motor Interference Effects.

Front Hum Neurosci 2020 29;14:566735. Epub 2020 Sep 29.

Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland.

Gait analysis involving cognitive-motor dual task (DT) is a diagnostic tool in geriatrics. Cognitive-motor interference effects during DT, such as decreased walking speed and increased step-to-step variability, have a high predictive value for fall risk and cognitive decline. Previously we showed the feasibility of DT during functional magnetic resonance imaging (fMRI) using an MRI-compatible stepping device. Here, we improved the DT-fMRI protocol with respect to task difficulty and signal robustness, making it more suitable for individualized analysis to better understand the neuronal substrates of cognitive-motor interference effects. Thirty healthy elderly subjects performed cognitive and motor single tasks (ST; stepping or finger tapping), as well as combined cognitive-motor DT during fMRI. After whole brain group level analysis, a region-of-interest (ROI) analysis and the computation of dual task costs (DTC = activation difference ratio ST/DT) at individual level were performed. Activations in the primary (M1) and secondary motor as well as in parietal and prefrontal cortex were measured at the group level during DT. Motor areas showed decreased activation whereas parietal and prefrontal areas showed increased activation in DT vs. ST. Stepping yielded more distinctive activations in DT vs. ST than finger tapping. At the individual level, the most robust activations (based on occurrence probability and signal strength) were measured in the stepping condition, in M1, supplementary motor area (SMA) and superior parietal lobule/intraparietal sulcus (SPL/IPS). The distribution of individual DTC in SPL/IPS during stepping suggested a separation of subjects in groups with high vs. low DTC. This study proposes an improved cognitive-motor DT-fMRI protocol and a standardized analysis routine of functional neuronal markers for cognitive-motor interference at the individual level.
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http://dx.doi.org/10.3389/fnhum.2020.566735DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7550687PMC
September 2020

Mass Cytometry-A Tool for the Curious: Networking in Berlin.

Cytometry A 2020 08 16;97(8):764-767. Epub 2020 Apr 16.

DRFZ Berlin, a Leibniz Institute, Berlin, Germany.

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http://dx.doi.org/10.1002/cyto.a.24015DOI Listing
August 2020

Hematopoietic stem cell response to acute thrombocytopenia requires signaling through distinct receptor tyrosine kinases.

Blood 2019 09 21;134(13):1046-1058. Epub 2019 Aug 21.

Institute for Clinical Chemistry and Laboratory Medicine.

Although bone marrow niche cells are essential for hematopoietic stem cell (HSC) maintenance, their interaction in response to stress is not well defined. Here, we used a mouse model of acute thrombocytopenia to investigate the cross talk between HSCs and niche cells during restoration of the thrombocyte pool. This process required membrane-localized stem cell factor (m-SCF) in megakaryocytes, which was regulated, in turn, by vascular endothelial growth factor A (VEGF-A) and platelet-derived growth factor-BB (PDGF-BB). HSCs and multipotent progenitors type 2 (MPP2), but not MPP3/4, were subsequently activated by a dual-receptor tyrosine kinase (RTK)-dependent signaling event, m-SCF/c-Kit and VEGF-A/vascular endothelial growth factor receptor 2 (VEGFR-2), contributing to their selective and early proliferation. Our findings describe a dynamic network of signals in response to the acute loss of a single blood cell type and reveal the important role of 3 RTKs and their ligands in orchestrating the selective activation of hematopoietic stem and progenitor cells (HSPCs) in thrombocytopenia.
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http://dx.doi.org/10.1182/blood.2019000721DOI Listing
September 2019

Assessment of the impact of sex in intensity, skin flares and central processing of histaminergic itch-A pilot study.

Exp Dermatol 2019 12 9;28(12):1493-1500. Epub 2019 Sep 9.

Department of Psychiatry, University of Basel, Basel, Switzerland.

Itch is the commonest skin-related symptom, and sex differences are increasingly recognised as important determinants in stratified medicine, but only little is known about sex differences in itch. Questionnaire-based studies indicated that women perceive itch as more intensive and bothersome in comparison with men. However, data of studies using standardised itch models to objectify sex differences are scarce and inconsistent. To determine sex differences in intensity, skin flares and central processing of histaminergic itch, we compared 15 female and 15 male healthy subjects in a double-blinded, within-subject, placebo-controlled study using a histamine skin prick itch model (histamine 1% applied onto the volar forearm) and functional MRI. We found trends in higher mean itch intensity (0.58 VAS, CI 95% 0.004-1.19, P = .056) and maximum itch intensity (men 3.93 VAS ± 0.39 SD at 3 minutes, women 4.73 VAS ± 0.31 SD at 4 minutes, P = .073) in women paralleled by a trend in a stronger positive correlation between itch intensity and blood oxygen level-dependent (BOLD) activity in brain structures identified during itch in comparison with men (r in women: .46, P = .08, r in men: .07, P = .79). The erythema and wheal following histamine skin pricking were (non-significantly) larger in men, indicating that higher mean itch intensities on the right volar forearm in women may not be explained by more intense flares. The comparison of the activation patterns between the sexes revealed increased activity in men compared to women in the left middle temporal gyrus (temporooccipital part)/lateral occipital cortex. Thus, our findings indicate that histaminergic itch perception and central itch processing differ between the sexes under standardised conditions.
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http://dx.doi.org/10.1111/exd.14021DOI Listing
December 2019

Golden-angle radial sparse parallel (GRASP) MRI in clinical routine detection of pituitary microadenomas: First experience and feasibility.

Magn Reson Imaging 2019 07 27;60:38-43. Epub 2019 Mar 27.

Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland; Division of Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland.

Background and purpose To demonstrate the clinical feasibility of a novel MRI pulse sequence, Golden-angle radial sparse parallel MRI (GRASP) through comparison to the current imaging technique, dynamic T1- weighted contrast enhanced (DCE) imaging in terms of image quality and lesion depiction in the detection of microlesions (microadenomas and cysts) of the pituitary gland.

Materials And Methods: 16 patients (11 microadenomas, 5 cysts) underwent two MRI examinations (Siemens 1.5T and 3T) on separate dates, one using standard DCE (temporal resolution 30 s) and the other using GRASP (temporal resolution of 4.4 s). Two neuroradiologists separately recorded measures of image quality (Scale 1-5, 5 = best), lesion size and contrast arrival times in terms of first and best lesion conspicuity.

Results: In qualitiative analysis there were no significant differences in terms of average visual image sharpness (DCE 3.9 ± 0.9, GRASP 3.9 ± 0.9) or visual contrast scores (DCE 4.1 ± 1.2, GRASP 4.4 ± 0.8). Pearson's correlation coefficients for interreader lesion measurements (width and height, mm) ranged from substantial to almost perfect agreement (r = 0.73 to 0.88). Analysis of contrast arrival times revealed an average lesion first-conspicuity time of 60.7 ± 16.7 s for DCE compared to 50.2 ± 10.3 s for GRASP with a difference of 10.5 ± 16.2 s (p = 0.023).

Conclusion: Depiction of pituitary microlesions is feasible with GRASP, which has the potential to increase sensitivity through higher temporal resolutions combined with isotropic acquisition allowing for multi-planar reconstructions; this remains to be proven in larger cohorts.
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http://dx.doi.org/10.1016/j.mri.2019.03.015DOI Listing
July 2019

Structured Reporting in Neuroradiology: Intracranial Tumors.

Front Neurol 2018 6;9:32. Epub 2018 Feb 6.

Division of Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland.

Purpose: The aim of this pilot study was to assess the clinical feasibility, diagnostic yield, advantages, and disadvantages of structured reporting for routine MRI-reading in patients with primary diagnosis of intracranial tumors as compared to traditional neuroradiological free text reporting.

Methods: A structured MRI reporting template was developed covering pathological, anatomical, and functional aspects in an itemized fashion. Retrospectively, 60 consecutive patients with first diagnosis of an intracranial tumor were selected from the radiology information system/PACS system. Structured reporting was performed by a senior neuroradiologist, blinded to clinical and radiological data. Reporting times were measured per patient. The diagnostic content was compared to free text reporting which was independently performed on the same MRI exams by two other neuroradiologists. The comparisons were categorized per item as: "congruent," "partially congruent," "incongruent," or "not mentioned in free-style report."

Results: Tumor-related items: congruent findings were found for all items (17/17) with congruence rates ranging between 98 and 39% per item. Four items achieved congruence rates ≥90%, 5 items >80%, and 9 items ≥70%. Partially congruent findings were found for all items in up to 50% per item. Incongruent findings were present in 7/17 items in up to 5% per item. Free text reports did not mention 12 of 17 items (range 7-43% per item). Non-tumor-related items, including brain atrophy, microangiopathy, vascular pathologies, and various extracranial pathologies, which were not mentioned in free-text reports between 18 and 85% per item. Mean reporting time for structured reporting was 7:49 min (3:12-17:06 min).

Conclusion: First results showed that expert structured reporting ensured reliable detection of all relevant brain pathologies along with reproducible documentation of all predefined diagnostic items, which was not always the case for free text reporting. A mean reporting time of 8 min per patient seems clinically feasible.
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http://dx.doi.org/10.3389/fneur.2018.00032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5808104PMC
February 2018

In Vivo Labeling by CD73 Marks Multipotent Stromal Cells and Highlights Endothelial Heterogeneity in the Bone Marrow Niche.

Cell Stem Cell 2018 02;22(2):262-276.e7

Institute of Physiology I, Life&Brain Center, Medical Faculty, University of Bonn, 53105 Bonn, Germany. Electronic address:

Despite much work studying ex vivo multipotent stromal cells (MSCs), the identity and characteristics of MSCs in vivo are not well defined. Here, we generated a CD73-EGFP reporter mouse to address these questions and found EGFP MSCs in various organs. In vivo, EGFP mesenchymal cells were observed in fetal and adult bones at proliferative ossification sites, while in solid organs EGFP cells exhibited a perivascular distribution pattern. EGFP cells from the bone compartment could be clonally expanded ex vivo from single cells and displayed trilineage differentiation potential. Moreover, in the central bone marrow CD73-EGFP specifically labeled sinusoidal endothelial cells, thought to be a critical component of the hematopoietic stem cell niche. Purification and molecular characterization of this CD73-EGFP population revealed an endothelial subtype that also displays a mesenchymal signature, highlighting endothelial cell heterogeneity in the marrow. Thus, the CD73-EGFP mouse is a powerful tool for studying MSCs and sinusoidal endothelium.
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http://dx.doi.org/10.1016/j.stem.2018.01.008DOI Listing
February 2018

GM-CSF producing autoreactive CD4 T cells in type 1 diabetes.

Clin Immunol 2018 03 8;188:23-30. Epub 2017 Dec 8.

CRTD-DFG Center for Regenerative Therapies Dresden, Carl Gustav Carus Faculty of Medicine, Technische Universität Dresden, Dresden 01307, Germany; Forschergruppe Diabetes, Klinikum rechts der Isar, Technische Universität München, Neuherberg, Germany; German Center for Diabetes Research (DZD), Neuherberg 85764, Germany. Electronic address:

The phenotype of autoreactive T cells in type 1 diabetes is described as Th1, Th17 and/or Th21, but is largely uncharacterized. We combined multi-parameter cytokine profiling and proliferation, and identified GM-CSF producing cells as a component of the response to beta cell autoantigens proinsulin and GAD65. Overall cytokine profiles of CD4 T cell were not altered in type 1 diabetes. In contrast, patients with recent onset type 1 diabetes had increased frequencies of proinsulin-responsive CD4CD45RA T cells producing GM-CSF (p=0.002), IFNγ (p=0.004), IL-17A (p=0.008), IL-21 (p=0.011), and IL-22 (p=0.007), and GAD65-responsive CD4CD45RA T cells producing IL-21 (p=0.039). CD4 T cells with a GM-CSFIFNγIL-17AIL-21IL-22 phenotype were increased in patients for responses to both proinsulin (p=0.006) and GAD65 (p=0.037). GM-CSF producing T cells are a novel phenotype in the repertoire of T helper cells in type 1 diabetes and consolidate a Th1/Th17 pro-inflammatory pathogenesis in the disease.
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http://dx.doi.org/10.1016/j.clim.2017.12.002DOI Listing
March 2018

Imaging gait analysis: An fMRI dual task study.

Brain Behav 2017 08 21;7(8):e00724. Epub 2017 Jul 21.

Division of Diagnostic and Interventional Neuroradiology Department of Radiology University of Basel Hospital and University of Basel Basel Switzerland.

Introduction: In geriatric clinical diagnostics, gait analysis with cognitive-motor dual tasking is used to predict fall risk and cognitive decline. To date, the neural correlates of cognitive-motor dual tasking processes are not fully understood. To investigate these underlying neural mechanisms, we designed an fMRI paradigm to reproduce the gait analysis.

Methods: We tested the fMRI paradigm's feasibility in a substudy with fifteen young adults and assessed 31 healthy older adults in the main study. First, gait speed and variability were quantified using the GAITRite electronic walkway. Then, participants lying in the MRI-scanner were stepping on pedals of an MRI-compatible stepping device used to imitate gait during functional imaging. In each session, participants performed cognitive and motor single tasks as well as cognitive-motor dual tasks.

Results: Behavioral results showed that the parameters of both gait analyses, GAITRite and fMRI, were significantly positively correlated. FMRI results revealed significantly reduced brain activation during dual task compared to single task conditions. Functional ROI analysis showed that activation in the superior parietal lobe (SPL) decreased less from single to dual task condition than activation in primary motor cortex and in supplementary motor areas. Moreover, SPL activation was increased during dual tasks in subjects exhibiting lower stepping speed and lower executive control.

Conclusion: We were able to simulate walking during functional imaging with valid results that reproduce those from the GAITRite gait analysis. On the neural level, SPL seems to play a crucial role in cognitive-motor dual tasking and to be linked to divided attention processes, particularly when motor activity is involved.
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http://dx.doi.org/10.1002/brb3.724DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5561304PMC
August 2017

MAPK Signaling and Inflammation Link Melanoma Phenotype Switching to Induction of CD73 during Immunotherapy.

Cancer Res 2017 09 26;77(17):4697-4709. Epub 2017 Jun 26.

Unit for RNA Biology, Department of Clinical Chemistry and Clinical Pharmacology, University of Bonn, Bonn, Germany.

Evolution of tumor cell phenotypes promotes heterogeneity and therapy resistance. Here we found that induction of CD73, the enzyme that generates immunosuppressive adenosine, is linked to melanoma phenotype switching. Activating MAPK mutations and growth factors drove CD73 expression, which marked both nascent and full activation of a mesenchymal-like melanoma cell state program. Proinflammatory cytokines like TNFα cooperated with MAPK signaling through the c-Jun/AP-1 transcription factor complex to activate CD73 transcription by binding to an intronic enhancer. In a mouse model of T-cell immunotherapy, CD73 was induced in relapse melanomas, which acquired a mesenchymal-like phenotype. We also detected CD73 upregulation in melanoma patients progressing under adoptive T-cell transfer or immune checkpoint blockade, arguing for an adaptive resistance mechanism. Our work substantiates CD73 as a target to combine with current immunotherapies, but its dynamic regulation suggests limited value of CD73 pretreatment expression as a biomarker to stratify melanoma patients. .
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http://dx.doi.org/10.1158/0008-5472.CAN-17-0395DOI Listing
September 2017

Targeting Adenosine in BRAF-Mutant Melanoma Reduces Tumor Growth and Metastasis.

Cancer Res 2017 09 26;77(17):4684-4696. Epub 2017 Jun 26.

Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia.

Increasing evidence exists for the role of immunosuppressive adenosine in promoting tumor growth and spread in a number of cancer types, resulting in poor clinical outcomes. In this study, we assessed whether the CD73-adenosinergic pathway is active in melanoma patients and whether adenosine restricts the efficacy of clinically approved targeted therapies for commonly mutated BRAF melanoma. In AJCC stage III melanoma patients, CD73 expression (the enzyme that generates adenosine) correlated significantly with patients presenting nodal metastatic melanoma, suggesting that targeting this pathway may be effective in advanced stage disease. In addition, dabrafenib and trametinib treatment of CD73 BRAF-mutant melanomas caused profound CD73 downregulation in tumor cells. Inhibition of BRAF and MEK in combination with the A2A adenosine receptor provided significant protection against tumor initiation and metastasis formation in mice. Our results suggest that targeting adenosine may enhance therapeutic responses for melanoma patients receiving targeted or immune-based therapies. .
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http://dx.doi.org/10.1158/0008-5472.CAN-17-0393DOI Listing
September 2017

Prevalence and function of Heschl's gyrus morphotypes in musicians.

Brain Struct Funct 2017 Nov 10;222(8):3587-3603. Epub 2017 Apr 10.

Division of Diagnostic and Interventional Neuroradiology, Department of Radiology, University of Basel Hospital, Petersgraben 4, 4031, Basel, Switzerland.

Morphological variations of the first transverse Heschl's gyrus (HG) in the human auditory cortex (AC) are common, yet little is known about their functional implication. We investigated individual morphology and function of HG variations in the AC of 41 musicians, using structural and functional magnetic resonance imaging (fMRI) as well as magnetoencephalography (MEG). Four main morphotypes of HG were (i) single HG, (ii) common stem duplication (CSD), (iii) complete posterior duplication (CPD), and (iv) multiple duplications (MD). The vast majority of musicians (90%) exhibited HG multiplications (type ii-iv) in either one (39%) or both (51%) hemispheres. In 27% of musicians, MD with up to four gyri were found. To probe the functional contribution of HG multiplications to auditory processing we performed fMRI and MEG with auditory stimulation using analogous instrumental tone paradigms. Both methods pointed to the recruitment of all parts of HG during auditory stimulation, including multiplications if present. FMRI activations extended with the degree of HG gyrification. MEG source waveform patterns were distinct for the different types of HG: (i) hemispheres with single HG and (ii) CSD exhibited dominant N1 responses, whereas hemispheres with (iii) CPD and (iv) MD exhibited dominant P1 responses. N1 dipole amplitudes correlated with the localization of the first complete Heschl's sulcus (cHS), designating the most posterior anatomical border of HG. P2 amplitudes were significantly higher in professional as compared to amateur musicians. The results suggest that HG multiplications occur much more frequently in musicians than in the general population and constitute a functional unit with HG.
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http://dx.doi.org/10.1007/s00429-017-1419-xDOI Listing
November 2017

Parietal lobe critically supports successful paired immediate and single-item delayed memory for targets.

Neurobiol Learn Mem 2017 May 24;141:53-59. Epub 2017 Mar 24.

Memory Clinic, University Center for Medicine of Aging Basel, Felix Platter Hospital, Burgfelderstrasse 101, Postfach, CH-4002 Basel, Switzerland; Faculty of Psychology, University of Basel, Missionsstrasse 60/62, CH-4055 Basel, Switzerland; Centre for Speech, Language and the Brain, Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, United Kingdom. Electronic address:

The parietal lobe is important for successful recognition memory, but its role is not yet fully understood. We investigated the parietal lobes' contribution to immediate paired-associate memory and delayed item-recognition memory separately for hits (targets) and correct rejections (distractors). We compared the behavioral performance of 56 patients with known parietal and medial temporal lobe dysfunction (i.e. early Alzheimer's Disease) to 56 healthy control participants in an immediate paired and delayed single item object memory task. Additionally, we performed voxel-based morphometry analyses to investigate the functional-neuroanatomic relationships between performance and voxel-based estimates of atrophy in whole-brain analyses. Behaviorally, all participants performed better identifying targets than rejecting distractors. The voxel-based morphometry analyses associated atrophy in the right ventral parietal cortex with fewer correct responses to familiar items (i.e. hits) in the immediate and delayed conditions. Additionally, medial temporal lobe integrity correlated with better performance in rejecting distractors, but not in identifying targets, in the immediate paired-associate task. Our findings suggest that the parietal lobe critically supports successful immediate and delayed target recognition memory, and that the ventral aspect of the parietal cortex and the medial temporal lobe may have complementary preferences for identifying targets and rejecting distractors, respectively, during recognition memory.
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http://dx.doi.org/10.1016/j.nlm.2017.03.016DOI Listing
May 2017

Functional magnetic resonance imaging in dermatology: The skin, the brain and the invisible.

Exp Dermatol 2017 10 21;26(10):845-853. Epub 2017 Apr 21.

Department of Dermatology, University Hospital Basel, Basel, Switzerland.

The skin and brain have a close bi-directional anatomical and functional connection. Historically, the skin-brain axis and the brain-skin axis have been well described. However, brain function in this context has only recently been demystified with the introduction of functional neuroimaging in dermatology. Functional neuroimaging, especially functional magnetic resonance imaging (fMRI), allows indirect visualisation of brain function. This review looks back to the beginnings of functional neuroimaging in dermatology, summarises the currently available dermatology-related fMRI studies and discusses the potential future role of fMRI as a stratifying tool in clinical dermatology and in the development of novel therapies. According to the main body of research made in this field, the focus is placed on experimental itch studies, which described the brain structures involved in itch processing, the regulation of the scratch response, contagious itch and itch suppression.
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http://dx.doi.org/10.1111/exd.13305DOI Listing
October 2017

Association between changes in cerebral grey matter volume and postoperative cognitive dysfunction in elderly patients: study protocol for a prospective observational cohort study.

BMC Anesthesiol 2016 11 25;16(1):118. Epub 2016 Nov 25.

Department of Anesthesia, Surgical Intensive Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, University of Basel, Spitalstrasse 21, CH-4031, Basel, Switzerland.

Background: Cognitive decline is frequently observed in elderly patients after major surgery. The pathophysiology of postoperative cognitive dysfunction (POCD) remains unclear. The aim of our investigation is to identify potential associations between brain volume change and POCD in elderly patients undergoing major surgery.

Methods: This is a prospective observational cohort study approved by the regional ethics board. We intend to compare specific brain volumes (hippocampus, lateral ventricle, total grey matter volume, regional cortical thickness) on magnetic resonance imaging and cognitive functions determined by a neuropsychological assessment battery in 70 study participants aged ≥65 years before and 3 and 12 months after major noncardiac surgery. Thirty volunteers will be included as matched nonsurgical controls. The primary endpoint of the study is the change in hippocampal volume over time in patients with and without POCD. The secondary endpoint is the correlation between the change in cerebral volume and cognitive function. We will follow the STROBE guidelines for reporting the results of observational studies.

Discussion: We hypothesize that surgery under general anesthesia is associated with a loss of cerebral grey matter, and that the degree of postoperative cognitive dysfunction correlates with the extent of atrophy in areas of the brain that are relevant for cognitive functions. The validation of reproducible anatomical biomarkers, such as the specific brain volumes examined in our cohort, may serve to evaluate the effect of preventive strategies and treatment interventions for POCD in follow-up studies.

Trial Registration: Clinicaltrials.gov NCT02045004 . Registered 22 January 2014. Kofam.ch SNCTP000001751. Registered 21 April 2016 (retrospectively registered).
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http://dx.doi.org/10.1186/s12871-016-0285-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5123242PMC
November 2016

Presurgical motor, somatosensory and language fMRI: Technical feasibility and limitations in 491 patients over 13 years.

Eur Radiol 2017 Jan 19;27(1):267-278. Epub 2016 May 19.

Division of Diagnostic and Interventional Neuroradiology, University Hospital Basel, Basel, Switzerland.

Objectives: To analyse the long-term feasibility and limitations of presurgical fMRI in a cohort of tumour and epilepsy patients with different MR-scanners at 1.5 and 3.0 T.

Methods: Four hundred and ninety-one consecutive patients undergoing presurgical fMRI between 2000 and 2012 on five different MR-scanners using established paradigms and semi-automated data processing were included. Success rates of task performance and BOLD-activation were determined for motor and somatosensory somatotopic mapping and language localisation. Procedural success, failures and imaging artifacts were analysed. MR-field strengths were compared.

Results: Two thousand three hundred fifteen of 2348 (98.6 %) attempted paradigms (1033 motor, 1220 speech, 95 somatosensory) were successfully performed. 100 paradigms (4.3 %) were repetition runs. 23 speech, 6 motor and 2 sensory paradigms failed for non-compliance and technical issues. Most language paradigm failures were noted in overt sentence generation. Average significant BOLD-activation was higher for motor than language paradigms (95.8 vs. 81.6 %). Most language paradigms showed significantly higher activation rates at 3 T compared to 1.5 T, whereas no significant difference was found for motor paradigms.

Conclusions: fMRI proved very robust for the presurgical localisation of the different motor and somatosensory body representations, as well as Broca's and Wernicke's language areas across different MR-scanners at 1.5 and 3.0 T over 13 years.

Key Points: • Standardised presurgical motor and language fMRI is robust across various MRI platforms. • Motor fMRI is less dependent on field strength than language fMRI. • fMRI task failures are relatively low and are reduced by paradigm repetition.
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http://dx.doi.org/10.1007/s00330-016-4369-4DOI Listing
January 2017

Neuropsychological Markers of Medial Perirhinal and Entorhinal Cortex Functioning are Impaired Twelve Years Preceding Diagnosis of Alzheimer's Dementia.

J Alzheimers Dis 2016 03;52(2):573-80

Memory Clinic, University Center for Medicine of Aging Basel, Felix-Platter Hospital, Basel, Switzerland.

Neurofibrillary pathology in Alzheimer's dementia (AD) is associated with cognitive impairments and cortical thinning, and begins in medial perirhinal cortex (mPRC) before entering entorhinal cortex (ERC). Thus, mPRC dysfunction (e.g., semantic object memory impairments) may predate or accompany ERC (i.e., episodic memory) dysfunction in the preclinical course of typical AD. We developed formulae estimating mPRC and ERC integrity (i.e., cortical thickness) using common neuropsychological tests in 31 healthy individuals and 58 early AD patients. These formulae estimated the longitudinal courses of mPRC and ERC functioning in independent groups of 28 optimally healthy individuals who developed AD (NC-AD) over 2.8-13.4 years and 28 pairwise-matched, stable, healthy individuals (NC-NC). Mixed models demonstrated significantly worse NC-AD than NC-NC estimated mPRC and ERC functioning at the earliest observation, 12 years preceding diagnosis, and a significant decline 4 years preceding the AD diagnosis. These findings demonstrate that specific neuropsychological impairments occur early in the course of preclinical AD and that tasks measuring mPRC functioning may serve as additional, powerful markers of preclinical AD.
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http://dx.doi.org/10.3233/JAD-150158DOI Listing
March 2016

Cortical thinning of parahippocampal subregions in very early Alzheimer's disease.

Neurobiol Aging 2016 Feb 10;38:188-196. Epub 2015 Nov 10.

Memory Clinic, University Center for Medicine of Aging Basel, Felix-Platter Hospital, Basel, Switzerland; Faculty of Psychology, University of Basel, Basel, Switzerland; Centre for Speech, Language and the Brain, Department of Experimental Psychology, University of Cambridge, Cambridge, UK.

The stereotypical pattern of neurofibrillary tangle spreading in the earliest stages of typical Alzheimer's dementia (AD) predicts that medial perirhinal cortex (mPRC) atrophy precedes entorhinal cortex (ERC) atrophy, whereas the status of the parahippocampal cortex (PHC) remains unclear. Atrophy studies have focused on more advanced rather than early AD patients, and usually segment the entire PRC as opposed to the mPRC versus lateral PRC (lPRC). The present study therefore determined the extent of ERC, mPRC, lPRC, and PHC atrophy in very early AD (mean Mini-Mental State Examination score = 26) patients and its presumed prodrome amnestic mild cognitive impairment (mean Mini-Mental State Examination score = 28) compared to demographically matched controls. PHG structures were manually segmented (blinded rater) and cortical thicknesses extracted. ERC and mPRC were similarly atrophied in both patient groups. The lPRC was atrophied in the AD group only. Thus, atrophic changes in very early AD broadly map onto the pattern of neurofibrillary tangle spreading and suggest that mPRC, ERC, and lPRC, but not PHC-associated functional impairments, characterize very early-stage AD.
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http://dx.doi.org/10.1016/j.neurobiolaging.2015.11.001DOI Listing
February 2016

A Genome-wide CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) Screen Identifies NEK7 as an Essential Component of NLRP3 Inflammasome Activation.

J Biol Chem 2016 Jan 9;291(1):103-9. Epub 2015 Nov 9.

From the Institute of Molecular Medicine and the Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, 81377 Munich, Germany

Inflammasomes are high molecular weight protein complexes that assemble in the cytosol upon pathogen encounter. This results in caspase-1-dependent pro-inflammatory cytokine maturation, as well as a special type of cell death, known as pyroptosis. The Nlrp3 inflammasome plays a pivotal role in pathogen defense, but at the same time, its activity has also been implicated in many common sterile inflammatory conditions. To this effect, several studies have identified Nlrp3 inflammasome engagement in a number of common human diseases such as atherosclerosis, type 2 diabetes, Alzheimer disease, or gout. Although it has been shown that known Nlrp3 stimuli converge on potassium ion efflux upstream of Nlrp3 activation, the exact molecular mechanism of Nlrp3 activation remains elusive. Here, we describe a genome-wide CRISPR/Cas9 screen in immortalized mouse macrophages aiming at the unbiased identification of gene products involved in Nlrp3 inflammasome activation. We employed a FACS-based screen for Nlrp3-dependent cell death, using the ionophoric compound nigericin as a potassium efflux-inducing stimulus. Using a genome-wide guide RNA (gRNA) library, we found that targeting Nek7 rescued macrophages from nigericin-induced lethality. Subsequent studies revealed that murine macrophages deficient in Nek7 displayed a largely blunted Nlrp3 inflammasome response, whereas Aim2-mediated inflammasome activation proved to be fully intact. Although the mechanism of Nek7 functioning upstream of Nlrp3 yet remains elusive, these studies provide a first genetic handle of a component that specifically functions upstream of Nlrp3.
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http://dx.doi.org/10.1074/jbc.C115.700492DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4697147PMC
January 2016

MITF and c-Jun antagonism interconnects melanoma dedifferentiation with pro-inflammatory cytokine responsiveness and myeloid cell recruitment.

Nat Commun 2015 Nov 4;6:8755. Epub 2015 Nov 4.

Unit for RNA Biology, Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany.

Inflammation promotes phenotypic plasticity in melanoma, a source of non-genetic heterogeneity, but the molecular framework is poorly understood. Here we use functional genomic approaches and identify a reciprocal antagonism between the melanocyte lineage transcription factor MITF and c-Jun, which interconnects inflammation-induced dedifferentiation with pro-inflammatory cytokine responsiveness of melanoma cells favouring myeloid cell recruitment. We show that pro-inflammatory cytokines such as TNF-α instigate gradual suppression of MITF expression through c-Jun. MITF itself binds to the c-Jun regulatory genomic region and its reduction increases c-Jun expression that in turn amplifies TNF-stimulated cytokine expression with further MITF suppression. This feed-forward mechanism turns poor peak-like transcriptional responses to TNF-α into progressive and persistent cytokine and chemokine induction. Consistently, inflammatory MITF(low)/c-Jun(high) syngeneic mouse melanomas recruit myeloid immune cells into the tumour microenvironment as recapitulated by their human counterparts. Our study suggests myeloid cell-directed therapies may be useful for MITF(low)/c-Jun(high) melanomas to counteract their growth-promoting and immunosuppressive functions.
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http://dx.doi.org/10.1038/ncomms9755DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4659938PMC
November 2015

Subcortical brain segmentation of two dimensional T1-weighted data sets with FMRIB's Integrated Registration and Segmentation Tool (FIRST).

Neuroimage Clin 2015 18;7:43-52. Epub 2014 Nov 18.

Department of Neurology, University Hospital Basel, Petersgraben 4, Basel 4031, Switzerland ; Division of Diagnostic and Interventional Neuroradiology, Department of Radiology, Petersgraben 4, Basel 4031, Switzerland.

Brain atrophy has been identified as an important contributing factor to the development of disability in multiple sclerosis (MS). In this respect, more and more interest is focussing on the role of deep grey matter (DGM) areas. Novel data analysis pipelines are available for the automatic segmentation of DGM using three-dimensional (3D) MRI data. However, in clinical trials, often no such high-resolution data are acquired and hence no conclusions regarding the impact of new treatments on DGM atrophy were possible so far. In this work, we used FMRIB's Integrated Registration and Segmentation Tool (FIRST) to evaluate the possibility of segmenting DGM structures using standard two-dimensional (2D) T1-weighted MRI. In a cohort of 70 MS patients, both 2D and 3D T1-weighted data were acquired. The thalamus, putamen, pallidum, nucleus accumbens, and caudate nucleus were bilaterally segmented using FIRST. Volumes were calculated for each structure and for the sum of basal ganglia (BG) as well as for the total DGM. The accuracy and reliability of the 2D data segmentation were compared with the respective results of 3D segmentations using volume difference, volume overlap and intra-class correlation coefficients (ICCs). The mean differences for the individual substructures were between 1.3% (putamen) and -25.2% (nucleus accumbens). The respective values for the BG were -2.7% and for DGM 1.3%. Mean volume overlap was between 89.1% (thalamus) and 61.5% (nucleus accumbens); BG: 84.1%; DGM: 86.3%. Regarding ICC, all structures showed good agreement with the exception of the nucleus accumbens. The results of the segmentation were additionally validated through expert manual delineation of the caudate nucleus and putamen in a subset of the 3D data. In conclusion, we demonstrate that subcortical segmentation of 2D data are feasible using FIRST. The larger subcortical GM structures can be segmented with high consistency. This forms the basis for the application of FIRST in large 2D MRI data sets of clinical trials in order to determine the impact of therapeutic interventions on DGM atrophy in MS.
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http://dx.doi.org/10.1016/j.nicl.2014.11.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4299953PMC
September 2015

Comparison between balanced steady-state free precession and standard spoiled gradient echo magnetization transfer ratio imaging in multiple sclerosis: methodical and clinical considerations.

Neuroimage 2015 Mar 20;108:87-94. Epub 2014 Dec 20.

Division of Medical Physics, Department of Radiology, University Hospital Basel, Petersgraben 4, 4031 Basel, Switzerland.

Different pathological processes like demyelination and axonal loss can alter the magnetisation transfer ratio (MTR) in brain tissue. The standard method to measure this effect is to scan the respective tissue twice, one with and one without a specific saturation pulse. A major drawback of this technique based on spoiled gradient echo (GRE) sequences relates to its long acquisition time due to the saturation pulses. Recently, an alternative concept for MT imaging based on balanced steady state free precession (bSSFP) has been proposed. Modification of the duration of the radiofrequency pulses for imaging allows scanning MT sensitive and non-sensitive images. The steady-state character of bSSFP with high intrinsic signal-to-noise ratio (SNR) allows three-dimensional (3D) whole brain MTR at high spatial resolution within short and thus clinically feasible acquisition times. In the present study, both bSSFP-MT and 2D GRE-MT imaging were used in a cohort of 31 patients with multiple sclerosis (MS) to characterize different normal appearing (NA) and pathological brain structures. Under the constraint of identical SNR and scan time, a 3.4 times higher voxel size could be achieved with bSSFP. This increased resolution allowed a more accurate delineation of the different brain structures, especially of cortex, hippocampus and MS lesions. In a multiple linear regression model, we found an association between MTR of cortical lesions and a clinical measure of disability (r= -0.407, p=0.035) in the bSSFP dataset only. The different relaxation weighting of the base images (T2/T1 in bSSFP, proton density in GRE) had no effects besides a larger spreading of the MTR values of the different NA structures. This was demonstrated by the nearly perfect linearity between the NA matter MTR of both techniques as well as in the absolute MTR differences between NA matter and the respective lesions.
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http://dx.doi.org/10.1016/j.neuroimage.2014.12.045DOI Listing
March 2015

Primary motor cortex activation and lateralization in patients with tumors of the central region.

Neuroimage Clin 2013 14;2:221-8. Epub 2013 Jan 14.

Division of Diagnostic and Interventional Neuroradiology, Department of Radiology and Nuclear Medicine, University Hospital of Basel, Basel, Switzerland.

Hemispheric lateralization is a frequently encountered phenomenon of cortical function. It describes the functional specialization of a region on one side of the brain for a given task. It is well characterized in motor and sensory, as well as language systems and becomes more and more known for various cognitive domains. While in the adult healthy brain hemispheric lateralization is mostly set, pathological processes may lead to cortical reorganization. In these cases neuroplasticity of the corresponding region in the non-dominant hemisphere seems to play an important role. In a previous study we investigated language associated regions in right-handed patients with frontal and temporal tumors of the left hemisphere. We observed a marked change of language lateralization in these patients towards the non-dominant hemisphere as measured by functional MRI (Partovi et al., 2012). In the present study we evaluated activation and lateralization of cortical motor areas in patients with tumors of the central region. BOLD fMRI was performed during unilateral voluntary movements of the contralesional hand in 87 patients. Individual correlations of measured BOLD-signals with the model hemodynamic reference function were determined on a ROI basis in single subjects and compared to those of 16 healthy volunteers. In volunteers the strongest activation is usually found in the M1 hand representation contralateral to the movement, while a weaker homotopic co-activation is observed in ipsilateral M1 (Stippich et al., 2007a). In the patient group our results show significant changes of motor activations, ranging from a reduction of M1 lateralization to equalization of M1 activations or even inversion of M1 lateralization during contralesional movements. This study corroborates in a large patient group the idea that lesions affecting M1 may lead to functional reorganization of cortical motor systems and in particular equalize hemispheric lateralization. However, it is not yet clear whether these changes are only an epiphenomenon or indeed reflect an attempt of recovery of brain function.
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http://dx.doi.org/10.1016/j.nicl.2013.01.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777836PMC
November 2013

Siglec-h on activated microglia for recognition and engulfment of glioma cells.

Glia 2013 Jul 30;61(7):1122-33. Epub 2013 Apr 30.

Neural Regeneration Group, Institute of Reconstructive Neurobiology, Medical Faculty, University Bonn, Bonn, Germany.

Sialic-acid-binding immunoglobulin-like lectin-h (Siglec-h) is a recently identified mouse-specific CD33-related Siglec that signals via DAP12/TYROBP. Expression of Siglec-h has been observed on plasmacytoid dendritic cells and microglia, but the ligand and the function of Siglec-h remained elusive. Here, we demonstrate gene transcription and protein expression of Siglec-h by mouse microglia after interferon-γ treatment or polarization into a M1-subtype. Microglial Siglec-h acted as phagocytosis receptor since targeting of microsphere beads to Siglec-h triggered their uptake into the microglia. The extracellular domain of Siglec-h protein bound to mouse glioma lines, but not to astrocytes or other normal mouse cells. Microglial cells stimulated to express Siglec-h engulfed intact glioma cells without prior induction of apoptosis and slightly reduced glioma cell number in culture. Phagocytosis of glioma cells by activated microglia was dependent on Siglec-h and its adapter molecule DAP12. Thus, data show that M1-polarized microglial cells can engulf glioma cells via a DAP12-mediated Siglec-h dependent mechanism.
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http://dx.doi.org/10.1002/glia.22501DOI Listing
July 2013

Increased volume and function of right auditory cortex as a marker for absolute pitch.

Cereb Cortex 2014 May 9;24(5):1127-37. Epub 2013 Jan 9.

Department of Neuroradiology, University of Heidelberg Medical School, 69120 Heidelberg, Germany.

Absolute pitch (AP) perception is the auditory ability to effortlessly recognize the pitch of any given tone without external reference. To study the neural substrates of this rare phenomenon, we developed a novel behavioral test, which excludes memory-based interval recognition and permits quantification of AP proficiency independently of relative pitch cues. AP- and non-AP-possessing musicians were studied with morphological and functional magnetic resonance imaging (fMRI) and magnetoencephalography. Gray matter volume of the right Heschl's gyrus (HG) was highly correlated with AP proficiency. Right-hemispheric auditory evoked fields were increased in the AP group. fMRI revealed an AP-dependent network of right planum temporale, secondary somatosensory, and premotor cortices, as well as left-hemispheric "Broca's" area. We propose the right HG as an anatomical marker of AP and suggest that a right-hemispheric network mediates AP "perception," whereas pitch "labeling" takes place in the left hemisphere.
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http://dx.doi.org/10.1093/cercor/bhs391DOI Listing
May 2014

Exercise might bias skeletal-muscle fat fraction calculation from Dixon images.

Neuromuscul Disord 2012 Oct;22 Suppl 2:S107-10

University of Basel Hospital, Department of Radiology and Nuclear Medicine, Division of Diagnostic and Interventional Neuroradiology, Petersgraben 4, CH-4031 Basel, Switzerland.

We examined the influence of a single exercise session on quantitative muscle fat fraction MRI measurements. Ten healthy volunteers were scanned on a 3T body scanner before and after a session of bilateral squats until muscular fatigue. Axial in- and opposed phase images were acquired at a fixed distance from the knee joint and fat fractions were calculated using a 2-point Dixon technique as well as muscle cross sectional area at the same position. After the squat session, calculated fat fraction in the quadriceps bilaterally appeared to be significantly decreased, while all but one non-exercised muscles showed no change. In conclusion exercise might modify the measured apparent fat fraction. Trials using quantitative MRI should consider the timing of scanning sessions and physical examinations to avoid bias caused by the influence of exercise on measurements.
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http://dx.doi.org/10.1016/j.nmd.2012.05.014DOI Listing
October 2012

Clinical functional MRI of sensorimotor cortex using passive motor and sensory stimulation at 3 Tesla.

J Magn Reson Imaging 2011 Aug;34(2):429-37

Department of Neuroradiology, University of Heidelberg Medical School, Heidelberg, Germany.

Purpose: To establish a passive motor paradigm for clinical functional MRI (fMRI) that could be beneficial for patients with motor or attention deficits who are not able to perform active motor tasks.

Materials And Methods: A novel standardized sensorimotor fMRI protocol was applied in 16 healthy volunteers at 3 Tesla (T) using active and passive motor tasks as well as sensory stimulation of hands and feet. Data analysis was carried out individually using a dynamic thresholding routine.

Results: Active motor tasks yielded time efficient and robust blood-oxygen-level-dependent (BOLD) signals in primary motor cortex. Noteworthy, it was possible to achieve equal activation levels within identical anatomical localization for passive and active motor tasks with these paradigms.

Conclusion: Patients unable to perform active movements can benefit from paradigms with passive motor and sensory stimulation. Therefore, we recommend these paradigms for functional somatotopic mapping of the central region at 3T in clinical routine.
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http://dx.doi.org/10.1002/jmri.22629DOI Listing
August 2011

[Magnetic resonance imaging of stents: quantitative in vitro examination at 3 Tesla].

Z Med Phys 2009 25;19(4):278-87. Epub 2009 Jun 25.

Sektion Experimentelle Radiologie, Neurologische Universitätsklinik Heidelberg, Im Neuenheimer Feld 400, D-69120 Heidelberg, Germany.

Purpose: The aim of this study was to qualitatively and quantitatively study MR artifacts of various stents on the basis of in vitro experiments. We were particularly interested whether sequence type and orientation of the stent with respect to the static magnetic field influences the artifact.

Material And Methods: We examined 18 stents of different material (nitinol, stainless steel, cobalt alloy), different design of the stent meshes (AccuLink, OmniLink, DynaLink, Xact, Protoge, Wallstent Monorail), different diameter (5-10mm) and different length (18-58 mm) with a turbo spin echo (TSE), a 2D-fast low angle shot (FLASH) and a 3D-FLASH sequence. The MR images were examined qualitatively with respect to possible artifacts. Furthermore we examined the MR data quantitatively: The contrast-noise-ratio (CNR) was determined both within the stent and outside (within the tube); based on these values we calculated the transparency factor P, furthermore we calculated the apparent vascular lumen within the tube and within the stent.

Results: The stents made of stainless steel and cobalt alloy displayed severe susceptibility artifacts. Therefore the vessel lumen within the stent could not be assessed. The nitinol stents showed different artifact patterns: The AccuLink and DynaLink stents showed less artifacts compared to the Xact and Protoge stents. Besides the susceptibility artifacts we found artifacts due to RF shielding by the stent mesh, particularly in TSE sequences.

Conclusion: A MR control of patients after stenting is possible and may yield diagnostic information when using the AccuLink or DynaLink stents. However, it is important to make sure that the stent is MR safe for the field strength used for the examination.
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http://dx.doi.org/10.1016/j.zemedi.2009.06.002DOI Listing
April 2010