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  • 1.
    Abdul Qadhr, Göran
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Molin, Daniel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Åström, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Suurküla, Madis
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Hagberg, Hans
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Whole-body diffusion-weighted imaging compared with FDG-PET/CT in staging of lymphoma patients2011In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 52, no 2, p. 173-180Article in journal (Refereed)
    Abstract [en]

    Background:

    Diffusion-weighted imaging (DWI) has become increasingly valuable in lymph node imaging, yet the clinical utility of this technique in the staging of lymphoma has not been established.

    Purpose:

    To compare whole-body DWI with FDG-PET/CT in the staging of lymphoma patients.

    Material and Methods:

    Thirty-one patients, eight with Hodgkin lymphoma (HL) and 23 with non-Hodgkin's lymphoma (18 aggressive and five indolent) underwent both whole-body DWI, whole-body MRI (T1W and T2W-STIR) and FDG-PET/CT. Lesions on whole-body DWI were only considered positive if they correlated with lesions on T1W and T2W-STIR images. The staging given by each technique was compared, according to the Ann Arbor staging system. Differences in staging were solved using biopsy results, and clinical and CT follow-ups as standard of reference.

    Results:

    The staging was the same for DWI and FDG-PET/CT in 28 (90.3%) patients and different in three (9.7%). Of the 28 patients with the same staging, 11 had stage IV in both techniques and 17 had stages 0-III. No HL or aggressive non-Hodgkin's lymphoma patients had different staging. Three indolent small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) lymphoma had higher staging with DWI when compared with FDG-PET/CT. One small subcutaneous breast lymphoma was not seen but all other extranodal sites were detected by both techniques.

    Conclusion:

    Whole-body DWI is a promising technique for staging of both (aggressive and indolent) non-Hodgkin's lymphoma and HL.

  • 2.
    Benedict, Christian
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Brooks, Samantha J
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Burgos, Jonathan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kempton, Matthew J
    Nordenskjöld, Richard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Nylander, Ruta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Kilander, Lena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Craft, Suzanne
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Schiöth, Helgi B
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Impaired Insulin Sensitivity as Indexed by the HOMA Score Is Associated With Deficits in Verbal Fluency and Temporal Lobe Gray Matter Volume in the Elderly2012In: Diabetes Care, ISSN 0149-5992, E-ISSN 1935-5548, Vol. 35, no 3, p. 488-494Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE

    Impaired insulin sensitivity is linked to cognitive deficits and reduced brain size. However, it is not yet known whether insulin sensitivity involves regional changes in gray matter volume. Against this background, we examined the association between insulin sensitivity, cognitive performance, and regional gray matter volume in 285 cognitively healthy elderly men and women aged 75 years from the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study.

    RESEARCH DESIGN AND METHODS

    Insulin sensitivity was calculated from fasting serum insulin and plasma glucose determinations using the homeostasis model assessment of insulin resistance (HOMA-IR) method. Cognitive performance was examined by a categorical verbal fluency. Participants also underwent a magnetic resonance imaging (MRI) brain scan. Multivariate analysis using linear regression was conducted, controlling for potential confounders (sex, education, serum LDL cholesterol, mean arterial blood pressure, and abdominal visceral fat volume).

    RESULTS

    The HOMA-IR was negatively correlated with verbal fluency performance, brain size (S1), and temporal lobe gray matter volume in regions known to be involved in speech production (Brodmann areas 21 and 22, respectively). No such effects were observed when examining diabetic (n = 55) and cognitively impaired (n = 27) elderly subjects as separate analyses.

    CONCLUSIONS

    These cross-sectional findings suggest that both pharmacologic and lifestyle interventions improving insulin signaling may promote brain health in late life but must be confirmed in patient studies.

  • 3.
    Benedict, Christian
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Brooks, Samantha J
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Nordenskjöld, Richard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Burgos, Jonathan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Le Grevès, Madeleine
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kilander, Lena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiovascular epidemiology.
    Schiöth, Helgi B
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Association between physical activity and brain health in older adults2013In: Neurobiology of Aging, ISSN 0197-4580, E-ISSN 1558-1497, Vol. 34, no 1, p. 83-90Article in journal (Refereed)
    Abstract [en]

    In the present cross-sectional study, we examined physical activity (PA) and its possible association with cognitive skills and brain structure in 331 cognitively healthy elderly. Based on the number of self-reported light and hard activities for at least 30 minutes per week, participants were assigned to 4 groups representing different levels of PA. The cognitive skills were assessed by the Mini Mental State Examination score, a verbal fluency task, and the Trail-making test as a measure of visuospatial orientation ability. Participants also underwent a magnetic resonance imaging of the brain. Multiple regression analysis revealed that greater PA was associated with a shorter time to complete the Trail-making test, and higher levels of verbal fluency. Further, the level of self-reported PA was positively correlated with brain volume, white matter, as well as a parietal lobe gray matter volume, situated bilaterally at the precuneus. These present cross-sectional results indicate that PA is a lifestyle factor that is linked to brain structure and function in late life.

  • 4.
    Berglund, Johan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Two-point dixon method with flexible echo times2011In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 65, no 4, p. 994-1004Article in journal (Refereed)
    Abstract [en]

    The two-point Dixon method is a proton chemical shift imaging technique that produces separated water-only and fat-only images from a dual-echo acquisition. It is shown how this can be achieved without the usual constraints on the echo times. A signal model considering spectral broadening of the fat peak is proposed for improved water/fat separation. Phase errors, mostly due to static field inhomogeneity, must be removed prior to least-squares estimation of water and fat. To resolve ambiguity of the phase errors, a corresponding global optimization problem is formulated and solved using a message-passing algorithm. It is shown that the noise in the water and fat estimates matches the Cramér-Rao bounds, and feasibility is demonstrated for in vivo abdominal breath-hold imaging. The water-only images were found to offer superior fat suppression compared with conventional spectrally fat suppressed images.

  • 5.
    Berglund, Johan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Three-point Dixon method enables whole-body water and fat imaging of obese subjects2010In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 63, no 6, p. 1659-1668Article in journal (Refereed)
    Abstract [en]

    Dixon imaging techniques derive chemical shift-separated water and fat images, enabling the quantification of fat content and forming an alternative to fat suppression. Whole-body Dixon imaging is of interest in studies of obesity and the metabolic syndrome, and possibly in oncology. A three-point Dixon method is proposed where two solutions are found analytically in each voxel. The true solution is identified by a multiseed three-dimensional region-growing scheme with a dynamic path, allowing confident regions to be solved before unconfident regions, such as background noise. 2 pi-Phase unwrapping is not required. Whole-body datasets (256 x 184 x 252 voxels) were collected from 39 subjects (body mass index 19.8-45.4 kg/m(2)), in a mean scan time of 5 min 15 sec. Water and fat images were reconstructed offline, using the proposed method and two reference methods. The resulting images were subjectively graded on a four-grade scale by two radiologists, blinded to the method used. The proposed method was found superior to the reference methods. It exclusively received the two highest grades, implying that only mild reconstruction failures were found. The computation time for a whole-body dataset was 1 min 51.5 sec +/- 3.0 sec. It was concluded that whole-body water and fat imaging is feasible even for obese subjects, using the proposed method.

  • 6. Bergström, G
    et al.
    Berglund, G
    Blomberg, A
    Brandberg, J
    Engström, G
    Engvall, J
    Eriksson, M
    de Faire, U
    Flinck, A
    Hansson, Mats G
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Centre for Research Ethics and Bioethics.
    Hedblad, B
    Hjelmgren, O
    Janson, Christer
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Jernberg, T
    Johnsson, Å
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Löfdahl, C-G
    Melander, O
    Östgren, C J
    Persson, A
    Persson, M
    Sandström, A
    Schmidt, C
    Söderberg, S
    Sundström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Toren, K
    Waldenström, A
    Wedel, H
    Vikgren, J
    Fagerberg, B
    Rosengren, A
    The Swedish CArdioPulmonary BioImage Study: objectives and design2015In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 278, no 6, p. 645-659Article in journal (Refereed)
    Abstract [en]

    Cardiopulmonary diseases are major causes of death worldwide, but currently recommended strategies for diagnosis and prevention may be outdated because of recent changes in risk factor patterns. The Swedish CArdioPulmonarybioImage Study (SCAPIS) combines the use of new imaging technologies, advances in large-scale 'omics' and epidemiological analyses to extensively characterize a Swedish cohort of 30 000 men and women aged between 50 and 64 years. The information obtained will be used to improve risk prediction of cardiopulmonary diseases and optimize the ability to study disease mechanisms. A comprehensive pilot study in 1111 individuals, which was completed in 2012, demonstrated the feasibility and financial and ethical consequences of SCAPIS. Recruitment to the national, multicentre study has recently started.

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  • 7.
    Bjermo, Helena
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism.
    Iggman, David
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm , Center for Clinical Research Dalarna.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Dahlman, Ingrid
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Persson, Lena
    Berglund, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Pulkki, Kari
    Basu, Samar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Oxidative Stress and Inflammation.
    Uusitupa, Matti
    Rudling, Mats
    Arner, Peter
    Cederholm, Tommy
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Risérus, Ulf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism.
    Effects of n-6 PUFAs compared with SFAs on liver fat, lipoproteins, and inflammation in abdominal obesity: a randomized controlled trial2012In: American Journal of Clinical Nutrition, ISSN 0002-9165, E-ISSN 1938-3207, Vol. 95, no 5, p. 1003-1012Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    Replacing SFAs with vegetable PUFAs has cardiometabolic benefits, but the effects on liver fat are unknown. Increased dietary n-6 PUFAs have, however, also been proposed to promote inflammation-a yet unproven theory.

    OBJECTIVE:

    We investigated the effects of PUFAs on liver fat, systemic inflammation, and metabolic disorders.

    DESIGN:

    We randomly assigned 67 abdominally obese subjects (15% had type 2 diabetes) to a 10-wk isocaloric diet high in vegetable n-6 PUFA (PUFA diet) or SFA mainly from butter (SFA diet), without altering the macronutrient intake. Liver fat was assessed by MRI and magnetic resonance proton (1H) spectroscopy (MRS). Proprotein convertase subtilisin/kexin type-9 (PCSK9, a hepatic LDL-receptor regulator), inflammation, and adipose tissue expression of inflammatory and lipogenic genes were determined.

    RESULTS:

    A total of 61 subjects completed the study. Body weight modestly increased but was not different between groups. Liver fat was lower during the PUFA diet than during the SFA diet [between-group difference in relative change from baseline; 16% (MRI; P < 0.001), 34% (MRS; P = 0.02)]. PCSK9 (P = 0.001), TNF receptor-2 (P < 0.01), and IL-1 receptor antagonist (P = 0.02) concentrations were lower during the PUFA diet, whereas insulin (P = 0.06) tended to be higher during the SFA diet. In compliant subjects (defined as change in serum linoleic acid), insulin, total/HDL-cholesterol ratio, LDL cholesterol, and triglycerides were lower during the PUFA diet than during the SFA diet (P < 0.05). Adipose tissue gene expression was unchanged.

    CONCLUSIONS:

    Compared with SFA intake, n-6 PUFAs reduce liver fat and modestly improve metabolic status, without weight loss. A high n-6 PUFA intake does not cause any signs of inflammation or oxidative stress. Downregulation of PCSK9 could be a novel mechanism behind the cholesterol-lowering effects of PUFAs.

  • 8.
    Bjerner, Tomas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wikström, Gerhard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ericsson, Anders
    Briley-Soebo, Karen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjørnerud, Atle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    In and ex vivo MR evaluation of acute myocardial ischemia in pigs by determining R1 in steady state after the administration of the intravascular contrast agent NC100150 injection2004In: Investigative Radiology, ISSN 0020-9996, E-ISSN 1536-0210, Vol. 39, no 8, p. 479-486Article in journal (Refereed)
  • 9.
    Bjerner, Tomas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wikström, Gerhard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    High in-plane resolution T2-weighted magnetic resonance imaging of acute myocardial ischemia in pigs using the intravascular contrast agent NC100150 injection.2004In: Investigative Radiology, ISSN 0020-9996, E-ISSN 1536-0210, Vol. 39, no 8, p. 470-478Article in journal (Refereed)
    Abstract [en]

    Rationale and Objectives: The intravascular contrast agent NC100150 injection was tested for its ability to demarcate nonperfused myocardium in a porcine model of coronary occlusion.

    Materials and Methods: A T2-weighted fast spin echo sequence was acquired ex vivo and in vivo during first pass and steady-state circulation of the contrast agent in 2 dosages (2 and 5 mg Fe/kg bw) or saline.

    Results: Ex vivo, in the high-dose group, the volume of nonperfused myocardium determined from T2-weighted images was 99% of that determined from photographs where perfused myocardium stained with fluorescein. A significantly higher contrast to noise ratio between perfused and nonperfused myocardium was found (both ex and in vivo in steady state) compared with the control group. During first pass, a significant reduction in signal intensity (74 ± 18%) was found in perfused myocardium after contrast injection.

    Conclusion: NC100150 injection, combined with T2-weighted turbo spin echo imaging, allowed detailed visualization of non-perfused myocardium in the steady state, which corresponded to the area at risk as determined by fluorescein.

  • 10.
    Bjornerud, Atle
    et al.
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Radiologi.
    Johansson, Lars
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Radiologi.
    The utility of superparamagnetic contrast agents in MRI: theoretical consideration and applications in the cardiovascular system.2004In: NMR Biomed, ISSN 0952-3480, Vol. 17, no 7, p. 465-77Article in journal (Other scientific)
  • 11.
    Björnerud, Atle
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Assessment of myocardial blood volume and water exchange: theoretical considerations and in vivo results.2003In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 49, no 5, p. 828-837Article in journal (Refereed)
  • 12.
    Bjørnerud, Atle
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars O.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan K.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Renal T(*)(2) perfusion using an iron oxide nanoparticle contrast agent: influence of T(1) relaxation on the first-pass response2002In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 47, no 2, p. 298-304Article in journal (Refereed)
    Abstract [en]

    Quantitative perfusion measurements require accurate knowledge of the correlation between first-pass signal changes and the corresponding tracer concentration in tissue. In the present study, a detailed analysis of first-pass renal cortical changes in T(1) and T(*)(2) following bolus injection of the iron oxide nanoparticle NC100150 Injection was investigated in a pig model using a double-echo gradient-echo sequence. The estimated change in 1/T(*)(2) during first pass calculated from single-echo sequences was compared to the true double-echo-derived 1/T(*)(2) curves. Using a single-echo (TE = 6 ms) spoiled gradient-echo sequence, the first-pass 1/T(*)(2) response following a bolus injection of 1 mg Fe/kg of NC100150 Injection was significantly underestimated due to counteracting T(1) effects. Signal response simulations showed that the relative error in the first-pass response decreased with increasing TE and contrast agent dose. However, both the maximum TE and the maximum dose are limited by excessive cortical signal loss, and the maximum TE is further limited by high temporal resolution requirements. The problem of T(1) contamination can effectively be overcome by using a double-echo gradient-echo sequence. This yields a first-pass response that truly reflects the tissue tracer concentration, which is a critical requirement for quantitative renal perfusion assessment.

  • 13.
    Bjørnerud, Atle
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Radiologi.
    Johansson, Lars O.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Briley-Sæbø, Karen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Radiologi.
    Ahlström, Håkan K.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Assessment of T1 and T2* effects in vivo and ex vivo using iron oxide nanoparticles in steady state: dependence on blood volume and water exchange2002In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 47, no 3, p. 461-471Article in journal (Refereed)
    Abstract [en]

    Accurate knowledge of the relationship between contrast agent concentration and tissue relaxation is a critical requirement for quantitative assessment of tissue perfusion using contrast-enhanced MRI. In the present study, using a pig model, the relationship between steady-state blood concentration levels of an iron oxide nanoparticle with a hydrated diameter of 12 nm (NC100150 Injection) and changes in the transverse and longitudinal relaxation rates (1/T2* and 1/T1, respectively) in blood, muscle, and renal cortex was investigated at 1.5 T. Ex vivo measurements of 1/T2* and 1/T1 were additionally performed in whole pig blood spiked with different concentrations of the iron oxide nanoparticle. In renal cortex and muscle, 1/T2* increased linearly with contrast agent concentration with slopes of 101 +/-22 s(-1)mM(-1) and 6.5 +/-0.9 s(-1)mM(-1) (mean +/- SD), respectively. In blood, 1/T2* increased as a quadratic function of contrast agent concentration, with different quadratic terms in the ex vivo vs. the in vivo experiments. In vivo, 1/T1 in blood increased linearly with contrast agent concentration, with a slope (T1-relaxivity) of 13.9 +/- 0.9 s(-1)mM(-1). The achievable increase in 1/T1 in renal cortex and muscle was limited by the rate of water exchange between the intra- and extravascular compartments and the 1/T1-curves were well described by a two-compartment water exchange limited relaxation model.

  • 14. Bolinder, Jan
    et al.
    Ljunggren, Östen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Metabolic Bone Diseases.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wilding, John
    Langkilde, Anna Maria
    Sugg, Jennifer
    Parikh, Shamik
    Effects of dapagliflozin on body weight, total fat mass, and regional adipose tissue distribution in patients with type 2 diabetes mellitus with inadequate glycemic control on metformin2012In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 97, no 3, p. 1020-1031Article in journal (Refereed)
    Abstract [en]

    Context:

    Dapagliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, reduces hyperglycemia in patients with type 2 diabetes mellitus (T2DM) by increasing urinary glucose excretion, and weight loss is a consistent associated finding.

    Objectives:

    Our objectives were to confirm weight loss with dapagliflozin and establish through body composition measurements whether weight loss is accounted for by changes in fat or fluid components.

    Design and Setting:

    This was a 24-wk, international, multicenter, randomized, parallel-group, double-blind, placebo-controlled study with ongoing 78-wk site- and patient-blinded extension period at 40 sites in five countries.

    Patients:

    Included were 182 patients with T2DM (mean values: women 63.3 and men 58.6 yr of age; hemoglobin A1c 7.17%, body mass index 31.9 kg/m2, and body weight 91.5 kg) inadequately controlled on metformin.

    Intervention:

    Dapagliflozin 10 mg/d or placebo was added to open-label metformin for 24 wk.

    Main Outcome Measures:

    Primary endpoint was total body weight (TBW) change from baseline at wk 24. Key secondary endpoints were waist circumference and dual-energy x-ray absorptiometry total-body fat mass (FM) changes from baseline at wk 24, and patient proportion achieving body weight reduction of at least 5% at wk 24. In a subset of patients, magnetic resonance assessment of visceral adipose tissue (VAT) and sc adipose tissue (SAT) volume and hepatic lipid content were also evaluated.

    Results:

    At wk 24, placebo-corrected changes with dapagliflozin were as follows: TBW, −2.08 kg [95% confidence interval (CI) = −2.84 to −1.31; P < 0.0001]; waist circumference, −1.52 cm (95% CI = −2.74 to −0.31; P = 0.0143); FM, −1.48 kg (95% CI = −2.22 to −0.74; P = 0.0001); proportion of patients achieving weight reduction of at least 5%, +26.2% (95% CI = 15.5 to 36.7; P < 0.0001); VAT, −258.4 cm3 (95% CI = −448.1 to −68.6; nominal P = 0.0084); SAT, −184.9 cm3 (95% CI = −359.7 to −10.1; nominal P = 0.0385). In the dapagliflozin vs. placebo groups, respectively, serious adverse events were reported in 6.6 vs. 1.1%; events suggestive of vulvovaginitis, balanitis, and related genital infection in 3.3 vs. 0%; and lower urinary tract infections in 6.6 vs. 2.2%.

    Conclusions:

    Dapagliflozin reduces TBW, predominantly by reducing FM, VAT and SAT in T2DM inadequately controlled with metformin.

  • 15.
    Briley-Saebo, Karen C.
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Johansson, Lars O.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Hustvedt, Svein Olaf
    Haldorsen, Anita G.
    Bjornerud, Atle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Fayad, Zahi A.
    Ahlström, Håkan K.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Clearance of iron oxide particles in rat liver: effect of hydrated particle size and coating material on liver metabolism2006In: Investigative Radiology, ISSN 0020-9996, E-ISSN 1536-0210, Vol. 41, no 7, p. 560-571Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: We sought to evaluate the effect of the particle size and coating material of various iron oxide preparations on the rate of rat liver clearance. MATERIALS AND METHODS: The following iron oxide formulations were used in this study: dextran-coated ferumoxide (size = 97 nm) and ferumoxtran-10 (size = 21 nm), carboxydextran-coated SHU555A (size = 69 nm) and fractionated SHU555A (size = 12 nm), and oxidized-starch coated materials either unformulated NC100150 (size = 15 nm) or formulated NC100150 injection (size = 12 nm). All formulations were administered to 165 rats at 2 dose levels. Quantitative liver R2* values were obtained during a 63-day time period. The concentration of iron oxide particles in the liver was determined by relaxometry, and these values were used to calculate the particle half-lives in the liver. RESULTS: After the administration of a high dose of iron oxide, the half-life of iron oxide particles in rat liver was 8 days for dextran-coated materials, 10 days for carboxydextran materials, 14 days for unformulated oxidized-starch, and 29 days for formulated oxidized-starch. CONCLUSIONS: The results of the study indicate that materials with similar coating but different sizes exhibited similar rates of liver clearance. It was, therefore, concluded that the coating material significantly influences the rate of iron oxide clearance in rat liver.

  • 16.
    Brooks, Samantha J
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Benedict, Christian
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Burgos, J
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Kempton, M J
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Nordenskjöld, Richard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Kilander, Lena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Nylander, Ruta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Schiöth, Helgi B
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Late-life obesity is associated with smaller global and regional gray matter volumes: a voxel-based morphometric study2013In: International Journal of Obesity, ISSN 0307-0565, E-ISSN 1476-5497, Vol. 37, no 2, p. 230-236Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: 

    Obesity adversely affects frontal lobe brain structure and function. Here we sought to show that people who are obese versus those who are of normal weight over a 5-year period have differential global and regional brain volumes.

    DESIGN: 

    Using voxel-based morphometry, contrasts were done between those who were recorded as being either obese or of normal weight over two time points in the 5 years prior to the brain scan. In a post-hoc preliminary analysis, we compared scores for obese and normal weight people who completed the trail-making task.

    SUBJECTS: 

    A total of 292 subjects were examined following exclusions (for example, owing to dementia, stroke and cortical infarcts) from the Prospective Investigation of the Vasculature in Uppsala Seniors cohort with a body mass index of normal weight (<25 kg m−2) or obese (30 kg m−2).

    RESULTS: 

    People who were obese had significantly smaller total brain volumes and specifically, significantly reduced total gray matter (GM) volume (GMV) (with no difference in white matter or cerebrospinal fluid). Initial exploratory whole brain uncorrected analysis revealed that people who were obese had significantly smaller GMV in the bilateral supplementary motor area, bilateral dorsolateral prefrontal cortex (DLPFC), left inferior frontal gyrus and left postcentral gyrus. Secondary more stringent corrected analyses revealed a surviving cluster of GMV difference in the left DLPFC. Finally, post-hoc contrasts of scores on the trail-making task, which is linked to DLPFC function, revealed that obese people were significantly slower than those of normal weight.

    CONCLUSION: 

    These findings suggest that in comparison with normal weight, people who are obese have smaller GMV, particularly in the left DLPFC. Our results may provide evidence for a potential working memory mechanism for the cognitive suppression of appetite that may lower the risk of developing obesity in later life.

  • 17.
    Carlbom, Lina
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Espes, Daniel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Lubberink, Mark
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Eriksson, Olof
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Division of Molecular Imaging.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Jansson, Leif
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Carlsson, Per-Ola
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Transplantation and regenerative medicine.
    Pancreatic perfusion and subsequent response to glucose in healthy individuals and patients with type 1 diabetes2016In: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 59, no 9, p. 1968-1972Article in journal (Refereed)
    Abstract [en]

    AIMS/HYPOTHESIS: The aim of this study was to investigate pancreatic perfusion and its response to a glucose load in patients with type 1 diabetes mellitus compared with non-diabetic ('healthy') individuals.

    METHODS: Eight individuals with longstanding type 1 diabetes and ten sex-, age- and BMI-matched healthy controls underwent dynamic positron emission tomography scanning with (15)O-labelled water before and after intravenous administration of glucose. Perfusion in the pancreas was measured. Portal and arterial hepatic perfusion were recorded as references.

    RESULTS: Under fasting conditions, total pancreatic perfusion was on average 23% lower in the individuals with diabetes compared with healthy individuals. Glucose increased total pancreatic and portal hepatic blood perfusion in healthy individuals by 48% and 38%, respectively. In individuals with diabetes there was no significant increase in either total pancreatic or portal hepatic perfusion.

    CONCLUSIONS/INTERPRETATION: Individuals with type 1 diabetes have reduced basal pancreatic perfusion and a severely impaired pancreatic and splanchnic perfusion response to intravenous glucose stimulation.

  • 18.
    Carlbom, Lina
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Espes, Daniel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Lubberink, Mark
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Martinell, Mats
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Family Medicine and Preventive Medicine.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Carlsson, Per-Ola
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Transplantation and regenerative medicine.
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Eriksson, Olof
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry.
    [(11)C]5-Hydroxy-Tryptophan PET for Assessment of Islet Mass During Progression of Type 2 Diabetes2017In: Diabetes, ISSN 0012-1797, E-ISSN 1939-327X, Vol. 66, no 5, p. 1286-1292Article in journal (Refereed)
    Abstract [en]

    [(11)C]5-hydroxy-tryptophan ([(11)C]5-HTP) PET of the pancreas has been shown to be a surrogate imaging biomarker of pancreatic islet mass. The change in islet mass in different stages of type 2 diabetes (T2D) as measured by non-invasive imaging is currently unknown. Here, we describe a cross-sectional study where subjects at different stages of T2D development with expected stratification of pancreatic islet mass were examined in relation to non-diabetic individuals. The primary outcome was the [(11)C]5-HTP uptake and retention in pancreas, as a surrogate marker for the endogenous islet mass.We found that metabolic testing indicated a progressive loss of beta cell function, but that this was not mirrored by a decrease in [(11)C]5-HTP tracer accumulation in the pancreas. This provides evidence of retained islet mass despite decreased beta cell function. The results herein indicates that beta cell dedifferentiation, and not necessarily endocrine cell loss, constitute a major cause of beta cell failure in T2D.

  • 19.
    Carlbom, Lina
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Weis, Jan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Pre-transplantation ³¹P-magnetic resonance spectroscopy for quality assessment of human pancreatic grafts: A feasibility study2017In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 39, p. 98-102Article in journal (Refereed)
    Abstract [en]

    Objective: To investigate the feasibility of using (31)P-MRS for objective non-invasive quality assessment of human pancreas grafts prior to transplantation or islet isolation.

    Materials and methods: Pancreata from 5 human donors, 3 males and 2 females, aged 49-78years, with body mass index (BMI) 22-31kg/m(2), were included. Pancreata were perfused with histidine-tryptophan-ketoglutarate solution during procurement and stored in hypothermic condition (4°C) for 21-44h. During the period of hypothermic storage repeated spectra were obtained for each graft by (31)P-MRS (1.5Tesla) to measure the cold ischemia time (CIT) dependent changes of the phosphorous metabolites adenosine triphosphate (ATP), phosphomonoesters (PME), phosphodiesters (PDE) and inorganic phosphate (Pi), in the grafts. Graft temperature was measured immediately before and after MR-examination. Reference spectrum for non-viable tissue was obtained after graft exposure to room temperature.

    Results: PME/Pi, PDE/Pi and ATP/Pi spectral intensities ratios decreased with increasing CIT, reflecting the decreased viability of the grafts. PME/Pi ratio was the most discriminatory variable at prolonged CIT. (31)P-MRS could be performed without significantly increasing graft temperature.

    Conclusions: (31)P-MRS may provide quantitative parameters for evaluating graft viability ex vivo, and is a promising tool for objective non-invasive assessment of the quality of human pancreas grafts prior to transplantation or islet isolation.

  • 20.
    Christoffersson, Gustaf
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Henriksnäs, Johanna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Rolny, Charlotte
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Caballero-Corbalán, José
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Segersvärd, Ralf
    Permert, Johan
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Carlsson, Per-Ola
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Phillipson, Mia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Clinical and Experimental Pancreatic Islet Transplantation to Striated Muscle: Establishment of a Vascular System Similar to that in Native Islets2010In: Diabetes, ISSN 0012-1797, E-ISSN 1939-327X, Vol. 59, no 10, p. 2569-2578Article in journal (Refereed)
    Abstract [en]

    Objective: Curing type 1 diabetes by transplanting pancreatic islets into the liver is associated with poor long-term outcome and graft failure at least partly due to inadequate graft revascularization. The aim of the current study was to evaluate striated muscle as a potential angiogenic site for islet transplantation. Research Design and Methods: The current study presents a new experimental model which is found applicable to clinical islet transplantation. Islets were implanted into striated muscle where after intra-islet vascular density and blood flow were visualized with intravital and confocal microscopy in mice, and by magnetic resonance imaging in three auto-transplanted pancreatectomized patients. Mice were rendered neutropenic by repeated injections of Gr-1 antibody and diabetes was induced by alloxan treatment. Results: Contrary to liver-engrafted islets, islets transplanted to mouse muscle were revascularized with vessel densities and blood flow entirely comparable to islets within intact pancreas. Initiation of islet revascularization at the muscular site was dependent on neutrophils, and the function of islets transplanted to muscle was proven by curing diabetic mice. The experimental data were confirmed in auto-transplanted patients where higher plasma volumes were measured in islets engrafted in forearm muscle compared to adjacent muscle tissue through high-resolution magnetic resonance imaging. Conclusions: This study presents a novel paradigm in islet transplantation whereby recruited neutrophils are crucial for the functionally restored intra-islet blood perfusion following transplantation to striated muscle under experimental and clinical situations.

  • 21.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Hansen, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Andersson, Jessika
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Hulthe, Johannes
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Clinically unrecognized myocardial infarction detected at MR imaging may not be associated with atherosclerosis2007In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 245, no 1, p. 103-110Article in journal (Refereed)
    Abstract [en]

    Purpose: To prospectively investigate whether there is support for the hypothesis that clinically unrecognized myocardial infarctions (UMIs) detected at magnetic resonance (MR) imaging have an atherosclerotic pathogenesis similar to that of recognized myocardial infarctions (RMIs).

    Materials and Methods: After ethics committee approval and informed consent were obtained, gadolinium-enhanced whole-body MR angiography and late-enhancement MR imaging were performed in 248 randomly chosen 70-year-old subjects (123 women, 125 men). Imaging included the aorta and the carotid, renal, and lower limb arteries to the ankle, but not the coronary arteries. Subjects with myocardial infarction (MI) scars at late-enhancement MR imaging were classified as having RMI (n = 11) (those with a diagnosis of MI at the hospital) or UMI (n = 49) (those without a diagnosis of MI at the hospital). The presence of 50% or higher luminal narrowing in any vessel at whole-body MR angiography was considered to represent significant atherosclerosis. Intima-media thickness of the common carotid artery was measured with ultrasonography. C-reactive protein level was measured, and coronary heart disease risk was estimated. Observers were blinded to any previous results. The chi(2) test analysis of variance, and Bonferroni correction were used for statistical analyses.

    Results: None of the measured parameters differed significantly between the group without MI scars and the UMI group, but parameters were significantly increased in the RMI group (P < .05) compared with those in the group without MI scars. Forty-two of 49 UMIs and nine of 11 RMIs were located within inferolateral segments of the left ventricle.

    Conclusion: MR imaging-detected UMIs might have a different pathogenesis from that of RMIs or may have the same pathogenesis but may manifest at an earlier stage.

  • 22.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Myocardial scars more frequent than expected - Magnetic resonance imaging detects potential risk group2006In: Journal of the American College of Cardiology, ISSN 0735-1097, E-ISSN 1558-3597, Vol. 48, no 4, p. 765-771Article in journal (Refereed)
    Abstract [en]

    Objectives: The aim of this study was to investigate the prevalence of clinically recognized myocardial infarctions (RMIs) and unrecognized myocardial infarctions (UMIs) in 70-year-old subjects, assessed with magnetic resonance imaging (MRI), and to relate the findings to cardiac function and morbidity. Background: Late enhancement MRI identifies myocardial scars and thereby has the potential to detect UMI. Methods: Cardiac MRI was performed on 259 randomly chosen 70-year-old subjects. Late enhancement and cine sequences were acquired, and the ejection fraction and left ventricular (LV) mass were calculated. Late enhancement involving the subendocardial layer was considered to represent myocardial infarction (MI) scars, and their volumes were calculated. Information on cardiac morbidity and risk factors was collected from medical records and from a health examination. Subjects with MI scars, with or without a hospital diagnosis of MI were classified as RMI or UMI, respectively. Results: The images from 248 subjects (123 women, 125 men) were assessable. Myocardial infarction scars were found in 60 subjects (24.2%), in 49 of whom (19.8%) they were UMIs. The volumes of the UMIs were significantly smaller than those of the RMIs. There was an increased frequency of chest pain symptoms among the subjects with UMI or RMI compared with those without MI scars. Ejection fraction was significantly lower and LV mass significantly larger in the subjects with UMI or RMI than in those without MI scars. Conclusions: Unrecognized MI detected with MRI was more frequent than expected in 70-year-old subjects. The subjects displaying these UMIs may represent a previously unknown potential risk group for future cardiovascular events.

  • 23.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Bjerner, Thomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    The exactness of left ventricular segmentation in cine magnetic resonance imaging and its impact on systolic function values2007In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 48, no 3, p. 285-291Article in journal (Refereed)
    Abstract [en]

    Purpose: To evaluate the impact of exactness of the segmentation of the left ventricle (LV), using cine magnetic resonance imaging (MRI). Material and methods: Steady-state free-precession cine MRI was performed on 100 randomly selected subjects. Myocardial borders were outlined on short-axis images using three methods: method 1 was computer assisted, excluding papillary muscles from the left ventricular mass (LVM); method 2 was similar but included papillary muscles; and method 3 was manually traced including papillary muscles. LV end-systolic (ES) and end-diastolic (ED) masses and volumes, ejection fraction (EF), stroke volume (SV), and cardiac output (CO) were calculated from these measurements. The difference between the ES and ED LVM was used to estimate the exactness of the methods. Results: Method 3 was the most exact, and method 1 was the least exact. The three methods generated differing EF, SV, and CO measurements. With an ES-ED LVM difference exceeding 20 g, the mean SV measurement error was 8.83.6 ml. Conclusion: Manual tracing proved more exact than computer-assisted quantification. Exactness had an impact on EF, SV, and CO measurements, and the ES-ED LVM difference can be used to identify assessments that would benefit from more exact segmentation.

  • 24.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Several sources of error in estimation of left ventricular mass with M-mode echocardiography in elderly subjects2011In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 116, no 4, p. 258-64Article in journal (Refereed)
    Abstract [en]

    Introduction. M-mode echocardiography estimates of the left ventricular mass (LVM) were greater than magnetic resonance imaging (MRI) estimates. There are substantial differences between the methods both in the means of measuring and the calculation formula. The aim of this study was to investigate whether any difference in estimates of LVM between M-mode echocardiography and MRI is due to the means of measuring or to the calculation formula, using MRI as the gold standard.

    Material and methods. M-mode echocardiography and MRI were performed on 229 randomly selected 70-year-old community-living subjects. LVM was calculated from echocardiography (LVM(echo)) and from MRI (LVM(MRI)) measurements using standard techniques. Additionally LVM was calculated with the echocardiography formula from echo-mimicking measurements made on MR images (LVM(MRI/ASE)).

    Results. There were significant differences between all three LVM estimates in women, in men, and in the entire population. Echocardiography estimated LVM to be larger than did MRI, and the LVM(MRI/ASE) estimate was larger than the LVM(MRI). The difference between LVM(MRI) and LVM(MRI/ASE) was larger than the difference between LVM(echo) and LVM(MRI/ASE). There was a low correlation between LVM(echo) and LVM(MRI) (R(2) = 0.46) as well as between LVM(MRI/ASE) and LVM(MRI) (R(2) = 0.65).

    Conclusion. The means of measuring and the calculation formula both independently add to the error in LVM estimation with M-mode echocardiography. The error of the calculation formula seems to be greater than the error of the means of measuring in a population of community-living elderly men and women.

  • 25.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Apolipoprotein B/A-I ratio related to visceral but not to subcutaneous adipose tissue in elderly Swedes2010In: Atherosclerosis, ISSN 0021-9150, E-ISSN 1879-1484, Vol. 211, no 2, p. 656-659Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To investigate whether the amount of visceral (VAT) or subcutaneous adipose tissue (SAT) independently of the other can determine the apolipoprotein (apo)B/A-I ratio. METHODS: VAT and SAT areas were assessed using magnetic resonance imaging in 247 randomly selected 70-year-old men and women who did not use lipid-lowering drugs. Their adipose tissue areas were compared to their apoB and apo A-I levels and to their apoB/A-I ratios. RESULTS: The VAT area and the gender were significantly related to the apoB/A-I ratio whereas the SAT area was not. There was a positive relationship between the VAT area and the apoB/A-I ratio. CONCLUSION: A positive relationship was established between the amount of VAT and the apoB/A-I ratio, whereas there was no relationship between the amount of SAT and the apoB/A-I ratio. This observation supports the notion that VAT is metabolically active.

  • 26.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Nylander, Ruta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Themudo, Raquel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Prevalence of unrecognized myocardial infarction detected with magnetic resonance imaging and its relationship to cerebral ischemic lesions in both sexes2011In: Journal of the American College of Cardiology, ISSN 0735-1097, E-ISSN 1558-3597, Vol. 58, no 13, p. 1372-1377Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: The purpose of this study was to investigate the prevalence of unrecognized myocardial infarction (UMI) detected with magnetic resonance imaging (MRI) and whether it is related to cerebral ischemic lesions on MRI in an elderly population-based cohort.

    BACKGROUND: There is a correlation between stroke and recognized myocardial infarction (RMI) and between stroke and UMI detected with electrocardiography, whereas the prevalence of stroke in subjects with MRI-detected UMI is unknown.

    METHODS: Cerebral MRI and cardiac late-enhancement MRI were performed on 394 randomly selected 75-year-old subjects (188 women, 206 men). Images were assessed for cerebral ischemic lesions and myocardial infarction (MI) scars. Medical records were scrutinized. Subjects with MI scars, with or without a hospital diagnosis of MI, were classified as RMI or UMI, respectively.

    RESULTS: UMIs were found in 120 subjects (30%) and RMIs in 21 (5%). The prevalence of UMIs (p = 0.004) and RMIs (p = 0.02) was greater in men than in women. Men with RMI displayed an increased prevalence of cortical and lacunar cerebral infarctions, whereas women with UMI more frequently had cortical cerebral infarctions (p = 0.003).

    CONCLUSIONS: MI scars are more frequent in men than in women at 75 years of age. The prevalence of RMI is related to that of cerebral infarctions.

  • 27.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Themudo, Raquel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiovascular epidemiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Long-term prognosis of unrecognized myocardial infarction detected with cardiovascular magnetic resonance in an elderly population2016In: Journal of Cardiovascular Magnetic Resonance, ISSN 1097-6647, E-ISSN 1532-429X, Vol. 18, no 1, p. 43-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Individuals with unrecognized myocardial infarctions (UMIs) detected with cardiovascular magnetic resonance (CMR) constitute a recently defined group whose prognosis has not been fully evaluated. However, increasing evidence indicate that these individuals may be at considerable cardiovascular risk. The aim of the present study was to investigate the prognostic impact of CMR detected UMIs for major adverse cardiac events (MACE) in community living elderly individuals.

    METHODS: Late gadolinium enhancement CMR was performed in 248 randomly chosen 70-year-olds. Individuals with myocardial infarction (MI) scars, with or without a hospital diagnosis of MI were classified as recognized MI (RMI) or UMI, respectively. Medical records and death certificates were scrutinized. MACE was defined as cardiac death, non-fatal MI, a new diagnosis of angina pectoris, or symptom-driven coronary artery revascularization.

    RESULTS: During follow-up (mean 11 years) MACE occurred in 10 % (n = 18/182) of the individuals without MI scars, in 20 % (n = 11/55) of the individuals with UMI, and in 45 % (n = 5/11) of the individuals with RMI, with a significant difference between the UMI group and the group without MI scars (p = 0.045), and between the RMI group and the group without MI scars (p = 0.0004). Cardiac death and/or non-fatal MI occurred in 15, 5, and 3 of the individuals in the NoMI, UMI, and RMI group respectively. Hazards ratios for MACE adjusted for risk factors and sex were 2.55 (95 % CI 1.20-5.42; p = 0.015) for UMI and 3.28 (95 % CI1.16-9.22; p = 0.025) for RMI.

    CONCLUSIONS: The presence of a CMR detected UMI entailed a more than double risk for MACE in community living 70-year-old individuals.

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  • 28.
    Ebeling Barbier, Charlotte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Themudo, Raquel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lindahl, Bertil
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Venge, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiovascular epidemiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Cardiac Troponin I Associated with the Development of Unrecognized Myocardial Infarctions Detected with MRI2014In: Clinical Chemistry, ISSN 0009-9147, E-ISSN 1530-8561, Vol. 60, no 10, p. 1327-1335Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    Late enhancement MRI (LE-MRI) and cardiac troponin I (cTnI) are sensitive methods to detect subclinical myocardial injury. We sought to investigate the relation between plasma concentrations of cTnI measured with a high-sensitivity assay (hs-cTnI) and the development of unrecognized myocardial infarctions (UMIs) detected with LE-MRI.

    METHODS:

    After approval from the ethics committee and written informed consent were obtained, LE-MRI was performed on 248 randomly selected community-living 70-year-old volunteers and hs-cTnI was determined with a highly sensitive premarket assay. Five years later these individuals were invited to a second LE-MRI, and 176 of them (82 women, 94 men), who did not have a hospital diagnosis of MI, constitute the present study population. LE-MR images were analyzed by 2 radiologists independently and in a consensus reading, blinded to any information on previous disease or assessments.

    RESULTS:

    New or larger UMIs were detected in 37 participants during follow-up. Plasma concentrations of hs-cTnI at 70 years of age, which were mainly within what is considered to be the reference interval, were related to new or larger UMIs at 75 years of age with an odds ratio of 1.98 per 1 unit increase in ln-transformed cTnI (95% CI, 1.17-3.35; P = 0.010). Plasma concentrations of hs-cTnI at 70 years of age were associated with the volumes of the UMIs detected at 75 years of age (P = 0.028).

    CONCLUSIONS:

    hs-cTnI in 70-year-old community-living women and men was associated with the development of MRI-detected UMIs within 5 years.

  • 29.
    Elmsjö, Albert
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry.
    Rosqvist, Fredrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism.
    Engskog, Mikael K R
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry.
    Haglöf, Jakob
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Iggman, David
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Arvidsson, Torbjörn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry.
    Risérus, Ulf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism.
    Pettersson, Curt
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry.
    NMR-based metabolic profiling in healthy individuals overfed different types of fat: links to changes in liver fat accumulation and lean tissue mass.2015In: Nutrition & Diabetes, ISSN 2044-4052, E-ISSN 2044-4052, Vol. 5, no 19, p. e182-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Overeating different dietary fatty acids influence the amount of liver fat stored during weight gain, however, the mechanisms responsible are unclear. We aimed to identify non-lipid metabolites that may differentiate between saturated (SFA) and polyunsaturated fatty acid (PUFA) overfeeding using a non-targeted metabolomic approach. We also investigated the possible relationships between plasma metabolites and body fat accumulation.

    METHODS: In a randomized study (LIPOGAIN study), n=39 healthy individuals were overfed with muffins containing SFA or PUFA. Plasma samples were precipitated with cold acetonitrile and analyzed by nuclear magnetic resonance (NMR) spectroscopy. Pattern recognition techniques were used to overview the data, identify variables contributing to group classification and to correlate metabolites with fat accumulation.

    RESULTS: We previously reported that SFA causes a greater accumulation of liver fat, visceral fat and total body fat, whereas lean tissue levels increases less compared with PUFA, despite comparable weight gain. In this study, lactate and acetate were identified as important contributors to group classification between SFA and PUFA (P<0.05). Furthermore, the fat depots (total body fat, visceral adipose tissue and liver fat) and lean tissue correlated (P(corr)>0.5) all with two or more metabolites (for example, branched amino acids, alanine, acetate and lactate). The metabolite composition differed in a manner that may indicate higher insulin sensitivity after a diet with PUFA compared with SFA, but this needs to be confirmed in future studies.

    CONCLUSION: A non-lipid metabolic profiling approach only identified a few metabolites that differentiated between SFA and PUFA overfeeding. Whether these metabolite changes are involved in depot-specific fat storage and increased lean tissue mass during overeating needs further investigation.

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  • 30.
    Engström, Mats
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Abdsaleh, Shahin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ståhlberg, Erik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    Jonsson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Serial gadolinium-enhanced magnetic resonance imaging and assessment of facial nerve function in Bell's palsy1997In: Otolaryngology and head and neck surgery, ISSN 0194-5998, E-ISSN 1097-6817, Vol. 117, no 5, p. 559-566Article in journal (Refereed)
    Abstract [en]

    Eleven patients with mild or moderate acute idiopathic peripheral facial palsy, so-called Bell's palsy, were serially examined by gadolinium-DTPA-enhanced MRI on mean days 11, 40, and 97 (third examination, n = 10) after the onset of palsy. Results of the clinical and neurophysiologic assessment of facial nerve function were compared with the gadolinium-enhanced MRI findings. Eight of the 11 patients demonstrated contrast enhancement of the facial nerve at the initial examination, but in 7 of them, the enhancement had disappeared by the time of the serial follow-up gadolinium-enhanced MRI scans. The disappearance of facial nerve enhancement was found to be related to clinical and neurophysiologic improvements in facial nerve function during recovery from Bell's palsy. The three patients whose scans were negative at the initial gadolinium-enhanced MRI examination had the same clinical severity of palsy, but initially they had milder neurophysiologic involvement than those who demonstrated enhancement; these three patients did not exhibit enhancement at serial follow-up scans. These findings indicate that the presence of enhancement at the initial MRI scan is not necessarily indicative of a poor prognosis for recovery.

  • 31. Eriksson, Jan W.
    et al.
    Jansson, Per-Anders
    Carlberg, Bo
    Hägg, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Kurland, Lisa
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Svensson, Maria K.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Ström, Conny
    Lönn, Lars
    Öjbrandt, Kristina
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Hydrochlorothiazide, but not Candesartan, aggravates insulin resistance and causes visceral and hepatic fat accumulation: the mechanisms for the diabetes preventing effect of Candesartan (MEDICA) Study2008In: Hypertension, ISSN 0194-911X, E-ISSN 1524-4563, Vol. 52, no 6, p. 1030-1037Article in journal (Refereed)
    Abstract [en]

    Treatment with angiotensin II receptor blockers is associated with lower risk for the development of type 2 diabetes mellitus compared with thiazide diuretics. The Mechanisms for the Diabetes Preventing Effect of Candesartan Study addressed insulin action and secretion and body fat distribution after treatment with candesartan, hydrochlorothiazide, and placebo. Twenty-six nondiabetic, abdominally obese, hypertensive patients were included in a multicenter 3-way crossover trial, and 22 completers (by predefined criteria; 10 men and 12 women) were included in the analyses. They underwent 12-week treatment periods with candesartan (C; 16 to 32 mg), hydrochlorothiazide (H; 25 to 50 mg), and placebo (P), respectively, and the treatment order was randomly assigned and double blinded. Intravenous glucose tolerance tests and euglycemic hyperinsulinemic (56 mU/m(2) per minute) clamps were performed. Intrahepatic and intramyocellular and extramyocellular lipid content and subcutaneous and visceral abdominal adipose tissue were measured using proton magnetic resonance spectroscopy and MRI. Insulin sensitivity (M-value) was reduced following H versus C and P (6.07+/-2.05, 6.63+/-2.04, and 6.90+/-2.10 mg/kg of body weight per minute, mean+/-SD; P<or=0.01). Liver fat content was higher (P<0.05) following H than both P and C. The subcutaneous to visceral abdominal adipose tissue ratio was reduced following H versus C and P (P<0.01). Glycosylated hemoglobin, alanine aminotransferase, aspartate aminotransferase, and high-sensitivity C-reactive protein levels were higher (P<0.05) after H, but not C, versus P. There were no changes in body fat, intramyocellular lipid, extramyocellular lipid, or first-phase insulin secretion. Blood pressure was reduced similarly by C and H versus P. In conclusion, visceral fat redistribution, liver fat accumulation, low-grade inflammation, and aggravated insulin resistance were demonstrated after hydrochlorothiazide but not candesartan treatment. These findings can partly explain the diabetogenic potential of thiazides.

  • 32.
    Eriksson, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Åberg, Ola
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Selvaraju, Ram K
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science.
    Eriksson, Olof
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Strategy to develop a MAO-A-resistant 5-hydroxy-L-[beta-C-11]tryptophan isotopologue based on deuterium kinetic isotope effects2014In: EJNMMI Research, E-ISSN 2191-219X, Vol. 4, no 1, article id 62Article in journal (Refereed)
    Abstract [en]

    Background

    The serotonin precursor 5-hydroxy-L-[β-11C]tryptophan ([11C]HTP) is in clinical use for localization of neuroendocrine tumors and has been suggested as a proxy marker for pancreatic islet cells. However, degradation by monoamine oxidase-A (MAO-A) reduces retention and the contrast to non-endocrine tissue.

    Methods

    A synthesis method was developed for 5-hydroxy-L-[β-11C2H]tryptophan ([11C]DHTP), an isotopologue of [11C]HTP, labeled with 11C and 2H at the β-position adjacent to the carbon involved in MAO-A decarboxylation. MAO-A-mediated degradation of [11C]DHTP was evaluated and compared to non-deuterated [11C]HTP.

    Results

    [11C]DHTP was synthesized with a radiochemical purity of >98%, radioactivity of 620 ± 190 MBq, and deuterium (2H or 2H2) incorporation at the β-position of 22% ±5%. Retention and resistance to MAO-A-mediated degradation of [11C]DHTP were increased in cells but not in non-human primate pancreas.

    Conclusions

    Partial deuteration of the β-position yields improved resistance to MAO-A-mediated degradation in vitro but not in vivo.

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  • 33.
    Eriksson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Espes, Daniel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Selvaraju, Ram K
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Jansson, Emma
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Lubberink, Mark
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Biglarnia, Alireza
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Transplantation Surgery.
    Eriksson, Jan W
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical diabetology and metabolism.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Carlsson, Per-Ola
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Transplantation and regenerative medicine.
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    The Positron Emission Tomography ligand [11C]5-Hydroxy-Tryptophan can be used as a surrogate marker for the human endocrine pancreas2014In: Diabetes, ISSN 0012-1797, E-ISSN 1939-327X, Vol. 63, no 10, p. 3428-3437Article in journal (Refereed)
    Abstract [en]

    In humans a well-developed serotonin system is localized to the pancreatic islets while being absent in exocrine pancreas. Assessment of pancreatic serotonin biosynthesis could therefore be used to estimate the human endocrine pancreas. Proof of concept was tested in a prospective clinical trial by comparisons of type 1 diabetic (T1D) patients, with extensive reduction of beta cells, with healthy volunteers (HV).C-peptide negative (i.e. insulin-deficient) T1D subjects (n=10) and HV (n=9) underwent dynamic Positron Emission Tomography with the radiolabeled serotonin precursor [(11)C]5-Hydroxy-Tryptophan ([(11)C]5-HTP).A significant accumulation of [(11)C]5-HTP was obtained in the pancreas of the HV, with large inter-individual variation. A substantial and highly significant reduction (66%) in the pancreatic uptake of [(11)C]5-HTP in T1D subjects was observed, and this was most evident in the corpus and caudal regions of the pancreas where beta-cells normally are the major constituent of the islets.[(11)C]5-HTP retention in the pancreas was reduced in T1D compared to non-diabetic subjects. Accumulation of [(11)C]5-HTP in the pancreas of both HV and subjects with T1D were in agreement with previously reported morphological observations on the beta cell volume implying that [(11)C]5-HTP retention is a useful non-invasive surrogate marker for the human endocrine pancreas.

  • 34.
    Eriksson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Jahan, Mahabuba
    Johnström, Peter
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Clinical Immunology.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Halldin, Christer
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    In vivo and in vitro characterization of [18F]-FE-(+)-DTBZ as a tracer for beta-cell mass2010In: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 37, no 3, p. 357-363Article in journal (Refereed)
    Abstract [en]

    INTRODUCTION: The positron emission tomography (PET) tracer 9-[(18)F]fluoroethyl-(+)-dihydrotetrabenazine ([(18)F]-FE-(+)-DTBZ) is a potential candidate for quantifying beta-cell mass in vivo. The purpose was to investigate in vitro and in vivo utility of this tracer for the assessment of beta-cell mass.

    METHODS: Three pigs were intravenously administered [(18)F]-FE-(+)-DTBZ and examined by PET/computed tomography. Binding parameters were estimated by kinetic modeling. In vitro k(D) and B(max) were determined by saturation binding studies of endocrine and exocrine human tissue homogenates. In vitro pancreatic uptake was determined by tissue autoradiography with pancreases from patients with types 1 (T1DM) and 2 diabetes mellitus (T2DM) and healthy controls.

    RESULTS: [(18)F]-FE-(+)-DTBZ had a k(D) of 3.5+/-1.0 nM, a B(max) of 382+/-108 fmol/mg protein and a specificity of 89+/-1.8% in islet homogenates. The total exocrine uptake was lower and 65% was nondisplaceable. No uptake difference was observed in pancreatic tissue slices from patients with T1DM, T2DM or healthy controls. The in vivo porcine pancreatic uptake reached a peak of standardized uptake value (SUV) of 2.8 with a low distribution volume ratio in all animals. Moderate to high tracer uptake was identified in the bile system and in bone.

    CONCLUSIONS: [(18)F]-FE-(+)-DTBZ binds to vesicular monoamine transporter 2 (VMAT2) with high specificity in pure islet tissue in vitro. However, there is high nondisplaceable binding to exocrine tissue. In addition, in vivo tracer metabolism and dehalogenation result in severe underestimation of porcine pancreatic VMAT2 expression and BCM. The results do not support [(18)F]-FE-(+)-DTBZ as a suitable tracer for in vivo beta-cell imaging.

  • 35.
    Eriksson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Selvaraju, Ram K
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Eriksson, Jan W
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical diabetology and metabolism.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Oncology.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Quantitative Imaging of Serotonergic Biosynthesis and Degradation in the Endocrine Pancreas2014In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 55, no 3, p. 460-465Article in journal (Refereed)
    Abstract [en]

    Serotonergic biosynthesis in the endocrine pancreas, of which the islets of Langerhans is the major constituent, has been implicated in insulin release and β cell proliferation. In this study, we investigated the feasibility of quantitative noninvasive imaging of the serotonergic metabolism in the pancreas using the PET tracer (11)C-5-hydroxy-l-tryptophan ((11)C-5-HTP).

    METHODS: Uptake of (11)C-5-HTP, and its specificity for key enzymes in the serotonergic metabolic pathway, was assessed in vitro (INS-1 and PANC1 cells and human islet and exocrine preparations) and in vivo (nonhuman primates and healthy and diabetic rats).

    RESULTS: In vitro tracer uptake in endocrine cells (INS-1 and human islets), but not PANC1 and exocrine cells, was mediated specifically by intracellular conversion into serotonin. Pancreatic uptake of (11)C-5-HTP in nonhuman primates was markedly decreased by inhibition of the enzyme dopa decarboxylase, which converts (11)C-5-HTP to (11)C-serotonin and increased after inhibition of monoamine oxidase-A, the main enzyme responsible for serotonin degradation. Uptake in the rat pancreas was similarly modulated by inhibition of monoamine oxidase-A and was reduced in animals with induced diabetes.

    CONCLUSION: The PET tracer (11)C-5-HTP can be used for quantitative imaging of the serotonergic system in the endocrine pancreas.

  • 36.
    Eriksson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Velikyan, Irina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Biomedical Radiation Sciences.
    Selvaraju, Ram K
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Kandeel, Fouad
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preclinical PET Platform.
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Korsgren, Olle
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Detection of Metastatic Insulinoma by Positron Emission Tomography with [(68)Ga]Exendin-4 -: a case report2014In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 99, no 5, p. 1519-1524Article in journal (Refereed)
    Abstract [en]

    Context:

    Insulinomas are the most common cause of endogenous hyperinsulinaemic hypoglycaemia in non-diabetic adult patients. They are usually benign and curative surgery is the "gold standard" treatment if they can be localized. Malignant insulinomas are seen in less than 10% and their prognosis is poor. The Glucagon Like Peptide-1 receptor (GLP-1R) is markedly upregulated in insulinomas - especially benign lesions which are difficult to localize with current imaging techniques.

    Objective:

    To assess the possibility of the detection of primary and metastatic insulinoma by PET using [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4 ([(68)Ga]Exendin-4) in a patient with severe hypoglycemia.

    Design:

    Dynamic and static PET/CT examination of a patient using [68Ga]Exendin-4.

    Setting:

    Uppsala University Hospital, Uppsala, Sweden.

    Patients:

    A patient presented with hypoglycemia requiring continuous intravenous glucose infusions. A pancreatic insulinoma was suspected and an exploratory laparotomy was urgently performed. At surgery, a tumor in the pancreatic tail with an adjacent metastasis was found and a distal pancreatic resection (plus splenectomy) and removal of lymph node was performed. Histopathology showed a WHO grade II insulinoma. Postoperatively hypoglycemia persisted but a PET/CT examination using the neuroendocrine marker [(11)C]-5-hydroxy-L-tryptophan was negative.

    Interventions:

    The patient was administered with [(68)Ga]Exendin-4 and examined by dynamic PET over the liver and pancreas.

    Main Outcome Measures:

    N/A

    Results:

    The stable GLP-1 analogue Exendin-4 was labeled with (68)Ga for PET imaging of GLP-1R expressing tumors. The patient was examined by [(68)Ga]Exendin-4-PET/CT which confirmed several small GLP-1R positive lesions in the liver and a lymph node that could not be conclusively identified by other imaging techniques. The results obtained from the [(68)Ga]Exendin-4-PET/CT examination provided the basis for continued systemic treatment.

    Conclusion:

    The results of the [(68)Ga]Exendin-4-PET/CT examination governed the treatment strategy of this particular patient and demonstrated the potential of this technique for future management of patients with this rare, but potentially fatal disease.

  • 37.
    Eriksson, Rolf
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Dobutamine-induced stress affects intracellular uptake of manganese: a quantitative magnetic resonance imaging study in pigs2004In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 21, no 4, p. 360-364Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    To determine whether there are differences in increase in longitudinal relaxation rate (DeltaR1) in the myocardium between bolus administration of Mn(2+) ions during rest and during dobutamine-induced stress and, additionally, to determine whether there are differences in DeltaR1 between bolus injection and infusion of Mn(2+) ions during dobutamine-induced stress.

    MATERIALS AND METHODS:

    Pigs were divided into three groups with six pigs in each group. All animals received 15 mumol MnCl(2)/kg of body weight (b.w.) intravenously either as a bolus injection (groups 1 and 2) or as an infusion over one minute (group 3). The animals in groups 2 and 3 were subjected to dobutamine stress before injection of MnCl(2), while those in group 1 were not given dobutamine. T1 was quantified in the myocardium and left ventricular blood pool before contrast injection and repeatedly during a one-hour postinjection period.

    RESULTS:

    A significant difference in DeltaR1 between the groups with and the group without dobutamine stress was noted in the myocardium up to 45 minutes after contrast agent injection. No such significant difference was found between pigs that received the contrast agent as a bolus injection compared to infusion.

    CONCLUSION:

    Dobutamine stress increases uptake of manganese ions in the myocardium. This increase was independent of whether the contrast agent was administered as a bolus injection or as an infusion.

  • 38.
    Eriksson, Rolf
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Briley Saebo, Karen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Uptake of MnCl2 and mangafodipir trisodium in the myocardium: a magnetic resonance imaging study in pigs2004In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 19, no 5, p. 564-569Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    To examine the changes in the longitudinal relaxation times (DeltaR1) induced in pig myocardium and blood following injections of 5, 10, and 15 micromol mangafodipir trisodium (Mn-DPDP) or MnCl2/kg of body weight (b.w.).

    MATERIALS AND METHODS:

    Twelve pigs were divided into two groups, one group receiving MnCl2 and the other receiving Mn-DPDP. Three consecutive doses of contrast agent (5, 10, and 15 micromol/kg of b.w.) were injected in each animal with a 40-minute time interval between each dose. Measurements of T1 in blood and myocardium were made 5, 15, 25, and 35 minutes after each injection. Additionally, relaxivity measurements in blood samples were performed.

    RESULTS:

    An increase in myocardial R1 was observed for both contrast agents at all concentration levels tested. This increase peaked 5 minutes after injection and then declined. An increase could still be detected 35 minutes after injection. The effect was larger when using MnCl2 than when using Mn-DPDP.

    CONCLUSION:

    The dissociation kinetics of Mn2+ from the DPDP ligand limits the relaxation increase of Mn-DPDP relative to that of MnCl2. On the other hand, the toxicity of MnCl2 may exclude it from clinical use.

  • 39.
    Eriksson, Rolf
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Karlsson, Jan Olof G.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Contrast enhancement of manganese-hydroxypropyl-tetraacetic acid, an MR contrast agent with potential for detecting differences in myocardial blood flow2006In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 24, no 4, p. 858-863Article in journal (Refereed)
    Abstract [en]

    Purpose: To determine whether the contrast agent MnHPTA has potential for detecting differences in myocardial blood flow.

    Materials and Methods: R1 in the myocardium was calculated from MR signal intensity measurements in 18 pigs after intravenous injection of 5, 15, or 25 mu mol MnHPTA/kg body weight. Measurements were made in each animal after administration at rest and during dobutamine-induced stress.

    Results: A difference of approximately 0.1 see(-1) in the R1 increase between rest and stress still remained 31 minutes after administration of 25 mu mol MnHPTA/kg body weight. When two consecutive MnHPTA injections were performed, the second injection induced a lower R1 increase than the corresponding first injection.

    Conclusion: MnHPTA at a dose of 25 mu mol/kg body weight (b.w.) has the potential to detect perfusion differences in myocardium. When two consecutive injections of MnHPTA were administered, the RI change after the second injection was affected by the earlier administration. Therefore, a protocol including more than one administration is not ideal for this contrast agent.

  • 40.
    Forsberg, Anders
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Agartz, Ingrid
    Department of Clinical Neuroscience, Karolinska Institutet and Hospital.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Henriksson, Karin
    Department of Laboratory Medicine, Lund University.
    Landmark-Based Software for Anatomical Measurements: A Precision Study2009In: Clinical anatomy (New York, N.Y. Print), ISSN 0897-3806, E-ISSN 1098-2353, Vol. 22, no 4, p. 456-462Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to develop a software program, called Landmarker, which would aid studies of complex anatomical morphometry by simplifying the manual identification of landmarks in 3D images. We also tested its precision on routine magnetic resonance imaging (MRI) scans. To understand human biological variation, there is a need to identify morphological characteristics from the exterior and the interior of human anatomy. MRI, as opposed to other radiographic methods (mainly based on X-ray techniques), supplies good soft tissue contrast, which allows for more complex assessments than what bony landmarks can provide. Because automation of this assessment is highly demanding, one of the primary goals for the new software was to enable more rapid identification of landmark sets in 3D image data. Repeat acquisition of head MRIs having a resolution of 0.94 x 0.94 x 1.20 mm3 were performed on 10 volunteers. Intra- and interoperator, as well as interacquisition variations of manual identification of exterior, craniofacial interior, and brain landmarks were studied. The average distances between landmarks were <1.8 mm, <2.3 mm, and <2.0 mm in the intra- and interoperator, and interacquisition evaluations, respectively. This study presents new software for time efficient identification of complex craniofacial landmarks in 3D MRI. To the best of our knowledge, no evaluation of software for rapid landmark-based analysis of complex anatomies from 3D MR data has yet been presented. This software may also be useful for studies in other anatomical regions and for other types of image data.

  • 41.
    Gao, Xiang
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Sandberg, Monica
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Quach, My
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Bodin, Birgitta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Jansson, Leif
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Effects of Mn-DPDP and manganese chloride on hemodynamics and glucose tolerance in anesthetized rats2014In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 55, no 3, p. 328-334Article in journal (Refereed)
    Abstract [en]

    Background Previous studies have demonstrated that magnetic resonance imaging may be a method of choice to visualize transplanted pancreatic islets. However, contrast agents may interfere with microcirculation and affect graft function. Purpose To evaluate the effects manganese-containing contrast media on regional blood flow and glucose tolerance. Material and Methods Anesthetized rats were injected intravenously with MnCl2 (10 mu M/kg body weight) or Mn-DPDP (Teslascan; 5 mu M/kg body weight). Blood flow measurements were made with a microsphere technique 10min later. In separate animals vascular arteriolar reactivity in isolated, perfused islets was examined. Furthermore, an intraperitoneal glucose tolerance test was performed in separate rats. Results Glucose tolerance was unaffected by both agents. No changes in regional blood flow were seen after administration of Mn-DPDP, except for an increase in arterial liver blood flow. MnCl2 increased all blood flow values except that of the kidney. MnCl2, but not Mn-DPDP, caused a vasoconstriction in isolated rat islet arterioles but only at very high doses. Conclusion Mn-DPDP administration does not affect glucose tolerance or regional blood flow, besides an increase in arterial hepatic blood flow, and may therefore be suitable for visualization of islets.

  • 42.
    Hagström, Emil
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Kilander, Lena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Nylander, Ruta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Michaëlsson, Karl
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Melhus, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical pharmacogenomics and osteoporosis.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiovascular epidemiology.
    Arnlöv, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular epidemiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Plasma Parathyroid Hormone Is Associated with Vascular Dementia and Cerebral Hyperintensities in Two Community-Based Cohorts2014In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 99, no 11, p. 4181-4189Article in journal (Refereed)
    Abstract [en]

    Context:

    In diseases with increased PTH such as hyperparathyroidism and chronic renal failure, dementia is common. Little is known of PTH and dementia in the community.

    Objective:

    We sought to investigate relations between PTH, clinical dementia and cerebral micro-vascular disease.

    Setting and Design:

    The Uppsala Longitudinal Study Of Adult Men (ULSAM) was prospective, baseline, 1991-1995; followup, 15.8 years. The Prospective Investigation Of The Vasculature In Uppsala Seniors (PIVUS) was cross-sectional, baseline, 2001. Both settings were community based.

    Participants and Main Outcome Measure:

    In the ULSAM study of 998 men (age 71) the association between PTH and dementia was investigated. In the PIVUS study of 406 men and women (age 70) the relation between PTH and magnetic resonance imaging signs of cerebral small vascular disease was investigated.

    Results:

    During followup, 56 individuals were diagnosed with vascular, 91 with Alzheimer's, and 59 with other dementias. In Cox-regression analyses, higher PTH was associated with vascular dementia (hazard ratio per 1 SD increase of PTH, 1.41; P < .01), but not with other dementias. The top tertile of PTH accounted for 18.5% of the population-attributable risk for vascular dementia, exceeding all other risk factors. In linear regression analysis in PIVUS, PTH was associated with increasing white matter hyperintensities (WMHI), reflecting increasing burden of cerebral small vessel disease (1 SD PTH increase, 0.31 higher category of WMHI; P = .016). All models were adjusted for vascular risk factors and mineral metabolism.

    Conclusions:

    In two community-based samples, PTH predicted clinically diagnosed and neuroimaging indices of vascular dementia and cerebral small vessel disease. Our data suggest a role for PTH in the development of vascular dementia.

  • 43.
    Hagström, Emil
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Michaëlsson, Karl
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Melhus, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical pharmacogenomics and osteoporosis.
    Hansen, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Ingelsson, Erik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular epidemiology.
    Sundström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiovascular epidemiology.
    Arnlöv, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular epidemiology.
    Plasma-Parathyroid Hormone Is Associated With Subclinical and Clinical Atherosclerotic Disease in 2 Community-Based Cohorts2014In: Arteriosclerosis, Thrombosis and Vascular Biology, ISSN 1079-5642, E-ISSN 1524-4636, Vol. 34, no 7, p. 1567-73Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Cardiovascular risk factors have different impact on different arterial territories. Diseases with elevated circulating parathyroid hormone (PTH) such as primary hyperparathyroidism and chronic renal failure have been shown to be associated with an increased risk of cardiovascular disease, predominantly heart or cerebrovascular diseases. However, data on the associations between circulating PTH and peripheral atherosclerosis are limited.

    APPROACH AND RESULTS: Two prospective, community-based studies were used. In 306 men and women, who were 70 years old, from the Prospective investigation of the vasculature in Uppsala seniors (PIVUS) study, cross-sectional relations between PTH and atherosclerotic burden assessed by whole-body magnetic resonance angiography were investigated. In 998 men, who were 71 years old, from the Uppsala longitudinal study of adult men (ULSAM) study, the association between PTH concentration and risk of subsequent nonfatal atherosclerotic disease (excluding coronary or cerebrovascular disease) was investigated. Adjusting for established vascular risk factors, PTH was associated with burden of atherosclerosis (increase in total atherosclerotic score per SD PTH increase: 0.04, 0.003-0.08; P=0.03) in the PIVUS study. During follow-up in the ULSAM study (median 16.7 years), 89 men were diagnosed with nonfatal atherosclerotic disease. In Cox-regression analyses adjusting for established vascular risk factors and mineral metabolism, higher PTH was associated with an increased risk of nonfatal atherosclerotic disease (hazard ratio for 1 SD increase of PTH: 1.55, 1.33-1.88; P<0.0001). Results were similar when including fatal atherosclerotic disease in the outcome.

    CONCLUSIONS: In 2 independent community-based cohorts, PTH was associated to the degree of atherosclerosis and risk of clinically overt atherosclerotic disease, respectively. Our data confirm and extend previous studies supporting a role for PTH in the development of atherosclerotic disease.

  • 44. Hammar, P.
    et al.
    Duvernoy, Olov
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lindahl, Bertil
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Nordenskjold, A. M.
    Hadziosmanovic, Nermin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Johansson, Lars O.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Unrecognized myocardial infarction assessed by CMR is associated with hemodynamically significant stenosis at coronary angiography in patients with stable angina pectoris2013In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 34, no S1, p. 818-818Article in journal (Other academic)
  • 45.
    Hammar, Per
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Nordenskjöld, Anna M
    Lindahl, Bertil
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Duvernoy, Olov
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Hadziosmanovic, Nermin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Unrecognized myocardial infarctions assessed by cardiovascular magnetic resonance are associated with the severity of the stenosis in the supplying coronary artery2015In: Journal of Cardiovascular Magnetic Resonance, ISSN 1097-6647, E-ISSN 1532-429X, Vol. 17, article id 98Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: A previous study has shown an increased prevalence of late gadolinium enhancement cardiovascular magnetic resonance (LGE CMR) detected unrecognized myocardial infarction (UMI) with increasing extent and severity of coronary artery disease. However, the coronary artery disease was evaluated on a patient level assuming normal coronary anatomy. Therefore, the aims of the present study were to investigate the prevalence of UMI identified by LGE CMR imaging in patients with stable angina pectoris and no known previous myocardial infarction; and to investigate whether presence of UMI is associated with stenotic lesions in the coronary artery supplying the segment of the myocardium in which the UMI is located, using coronary angiography to determine the individual coronary anatomy in each patient.

    METHODS: In this prospective multicenter study, we included patients with stable angina pectoris and without prior myocardial infarction, scheduled for coronary angiography. A LGE CMR examination was performed prior to the coronary angiography. The study cohort consisted of 235 patients (80 women, 155 men) with a mean age of 64.8 years.

    RESULTS: UMIs were found in 25 % of patients. There was a strong association between stenotic lesions (≥70 % stenosis) in a coronary artery and the presence of an UMI in the myocardial segments supplied by the stenotic artery; it was significantly more likely to have an UMI downstream a stenosis ≥ 70 % as compared to < 70 % (OR 5.1, CI 3.1-8.3, p < 0.0001). 56 % of the UMIs were located in the inferior and infero-lateral myocardial segments, despite predominance for stenotic lesions in the left anterior descending artery.

    CONCLUSION: UMI is common in patients with stable angina and the results indicate that the majority of the UMIs are of ischemic origin due to severe coronary atherosclerosis. In contrast to what is seen in recognized myocardial infarctions, UMIs are predominately located in the inferior and infero-lateral myocardial segments.

    TRIAL REGISTRATION: The PUMI study is registered at ClinicalTrials.gov ( NCT01257282 ).

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  • 46.
    Hansen, Tomas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Whole-body screening of atherosclerosis with magnetic resonance angiography.2007In: Topics in Magnetic Resonance Imaging (TMRI), ISSN 0899-3459, E-ISSN 1536-1004, Vol. 18, no 5, p. 329-337Article in journal (Refereed)
    Abstract [en]

    With whole-body magnetic resonance angiography (WBMRA), it is possible to examine the whole arterial tree except intracranial and coronary vessels in a single examination without the risks involved in ionizing radiation or arterial cannulation. Whole-body magnetic resonance angiography is well suited for repeated clinical examinations in patients with systemic diseases such as vasculitis or atherosclerosis and can also be used for scientific purposes. On the basis of the WBMRA overview, a possible further development of the WBMRA concept can be to perform further acquisitions at sites with atherosclerotic plaques with higher-resolution scans to determine the degree of stenosis more accurately or to achieve plaque characterization. A total validation of WBMRA compared with digital subtraction angiography (DSA) is not possible owing to the hazards of ionizing radiation. Studies have shown a high sensitivity and specificity for the pelvic and lower limb arteries in comparison with DSA. No systematic validation against DSA has been performed for the renal, aortic, and carotid arteries. Various methods have been used, however, for confirmation of vascular abnormalities found on WBMRA such as ultrasonography, dedicated MRA, or DSA, with reasonably high agreement. The WBMRA method has not been studied with regard to prediction of future cardiovascular (CV) events, as have intima media thickness, coronary artery calcium scoring, and the ankle-brachial index. The full usefulness of WBMRA in an epidemiological setting and as a complementary screening tool for assessing CV risk still needs to be validated against future CV events.

  • 47.
    Hansen, Tomas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Söderberg, S.
    Hulthe, J.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Internal Medicine.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Visceral adipose tissue, adiponectin levels and insulin resistance are related to atherosclerosis as assessed by whole-body magnetic resonance angiography in an elderly population2009In: Atherosclerosis, ISSN 0021-9150, E-ISSN 1879-1484, Vol. 205, no 1, p. 163-167Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The principal aim of this study was to determine whether the amount of visceral adipose tissue (VAT) is more related than subcutaneous adipose tissue (SAT) to atherosclerosis assessed by whole-body MRA (WBMRA). A further objective was to investigate whether traditional risk factors, inflammation, or adipokines could explain the hypothesized relationship between VAT and atherosclerosis. METHODS: Men and women aged 70 were recruited from the general population into the Prospective Investigation of The Vasculature in Uppsala Seniors (PIVUS) and 306 of them underwent WBMRA in a clinical 1.5-T scanner. The arterial tree was assessed for degree of stenosis or occlusion and a total atherosclerotic score (TAS) was established. Information on risk factors and BMI and on SAT and VAT, segmented on an axial MR scan was collected. Adiponectin, leptin, and high sensitive C-reactive protein (hsCRP) were measured in serum. HOMA index was used as a marker of insulin resistance. RESULTS: VAT was related to TAS independently of gender, total obesity (BMI), amount of SAT, hsCRP and also to the traditional risk factors included in the Framingham risk score (FRS) in an elderly population. Adiponectin or the HOMA insulin resistance, but not leptin or VAT, together with FRS was significantly related to TAS in a multiple censored regression model. CONCLUSION: Adiponectin attenuated the relationship between VAT and TAS, suggesting that adiponectin and insulin resistance is an important link between visceral adiposity and atherosclerosis.

  • 48.
    Hansen, Tomas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    A total atherosclerotic score for whole-body MRA and its relation to traditional cardiovascular risk factors2008In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 18, no 6, p. 1174-1180Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to create a scoring system for whole-body magnetic resonance angiography (WBMRA) that allows estimation of atherosclerotic induced luminal narrowing, and determine whether the traditional cardiovascular (CV) risk factors included in the Framingham risk score (FRS) were related to this total atherosclerotic score (TAS) in an elderly population. A group of 306 subjects, aged 70, were recruited from the general population and underwent WBMRA in a 1.5-T scanner. Three-dimensional sequences were acquired after administration of one i.v. injection of 40 ml gadodiamide. The arterial tree was divided into five territories (carotid, aorta, renal, upper and lower leg) comprising 26 vessel segments, and assessed according to its degree of stenosis or occlusion. FRS correlated to TAS (r=0.30, P < 0.0001), as well as to the atherosclerotic score for the five individual territories. Of the parameters included in the FRS, male gender (P < 0.0001), systolic blood pressure (P=0.0002), cigarette pack-years (P=0.0008) and HDL cholesterol (P=0.008) contributed to the significance. A scoring system for WBMRA was created. The significant relation towards traditional CV risk factors indicates that the proposed scoring system could be of value for assessing atherosclerotically induced luminal narrowing.

  • 49.
    Hansen, Tomas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Wanhainen, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Vascular Surgery.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Radiology.
    Lymph nodes as a potential pitfall in carotid plaque imaging with FDG-PET/CT2011In: Atherosclerosis, ISSN 0021-9150, E-ISSN 1879-1484, Vol. 215, no 1, p. 247-248Article in journal (Refereed)
  • 50.
    Hansen, Tomas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Johansson, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Radiology.
    The Prevalence and Quantification of Atherosclerosis in an Elderly Population Assessed by Whole-Body Magnetic Resonance Angiography2007In: Arteriosclerosis, Thrombosis and Vascular Biology, ISSN 1079-5642, E-ISSN 1524-4636, Vol. 27, no 3, p. 649-654Article in journal (Refereed)
    Abstract [en]

    Objective-The principal aim of the present study was to explore the feasibility of using whole-body magnetic resonance angiography to assess atherosclerosis in different vascular territories in a cohort of elderly. Methods and Results-Three hundred six 70-year-old subjects (145 women, 161 men) recruited from a population-based cohort study (Prospective Investigation of the Vasculature in Uppsala Seniors, ie, the PIVUS study) underwent 1.5-T whole-body magnetic resonance angiography with gadodiamide. The arteries were divided into 26 segments. In total, 7956 vessel segments were evaluated with 7900 segments (99.3%) possible to evaluate. Of these, 7186 segments (91%) were normal. Luminal narrowing of ≥50% was observed in 9 (1.5%) of the renal arteries, 12 (1.8%) of the carotid arteries, in 31 segments (1.1%) of the pelvic/upper leg territories, and in 136 segments (6.2%) of territories in the lower leg. Approximately one-third of the sample had no vascular abnormalities, one-third had stenoses of <50%, and the remainder had stenoses ≥50% or occlusions. Six subjects (2%) had aortic aneurysms. In subjects without evident vascular disease, 26% had significant vascular abnormalities. Conclusions-Whole-body magnetic resonance angiography performed with a clinical scanner can be used for quantifying atherosclerosis in different vascular territories in a single examination in an elderly population.

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