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  • 1.
    af Bjerkén, Sara
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Flygare, Carolina
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Remes, Jussi
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Strandberg, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Eriksson, Linda
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Bäckström, David C.
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Reliability and validity of visual analysis of [18F]FE-PE2I PET/CT in early Parkinsonian disease2023Ingår i: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 44, nr 5, s. 397-406Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: [18F]FE-PE2I (FE-PE2I) is a new radiotracer for dopamine transporter (DAT) imaging with PET. The aim of this study was to evaluate the visual interpretation of FE-PE2I images for the diagnosis of idiopathic Parkinsonian syndrome (IPS). The inter-rater variability, sensitivity, specificity, and diagnostic accuracy for visual interpretation of striatal FE-PE2I compared to [123I]FP-CIT (FP-CIT) single-photon emission computed tomography (SPECT) was evaluated.

    Methods: Thirty patients with newly onset parkinsonism and 32 healthy controls with both an FE-PE2I and FP-CIT were included in the study. Four patients had normal DAT imaging, of which three did not fulfil the IPS criteria at the clinical reassessment after 2 years. Six raters evaluated the DAT images blinded to the clinical diagnosis, interpreting the image as being ‘normal’ or ‘pathological’, and assessed the degree of DAT-reduction in the caudate and putamen. The inter-rater agreement was assessed with intra-class correlation and Cronbach’s α. For calculation of sensitivity and specificity, DAT images were defined as correctly classified if categorized as normal or pathological by ≥4/6 raters.

    Results: The overall agreement in visual evaluation of the FE-PE2I- and FP-CIT images was high for the IPS patients (α = 0.960 and 0.898, respectively), but lower in healthy controls (FE-PE2I: α = 0.693, FP-CIT: α = 0.657). Visual interpretation gave high sensitivity (both 0.96) but lower specificity (FE-PE2I: 0.86, FP-CIT: 0.63) with an accuracy of 90% for FE-PE2I and 77% for FP-CIT.

    Conclusion: Visual evaluation of FE-PE2I PET imaging demonstrates high reliability and diagnostic accuracy for IPS.

  • 2.
    af Bjerkén, Sara
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Stenmark Persson, Rasmus
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap. Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Barkander, Anna
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Karalija, Nina
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Pelegrina-Hidalgo, Noelia
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Gerhardt, Greg A
    Virel, Ana
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Strömberg, Ingrid
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Noradrenaline is crucial for the substantia nigra dopaminergic cell maintenance2019Ingår i: Neurochemistry International, ISSN 0197-0186, E-ISSN 1872-9754, Vol. 131, artikel-id 104551Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In Parkinson's disease, degeneration of substantia nigra dopaminergic neurons is accompanied by damage on other neuronal systems. A severe denervation is for example seen in the locus coerulean noradrenergic system. Little is known about the relation between noradrenergic and dopaminergic degeneration, and the effects of noradrenergic denervation on the function of the dopaminergic neurons of substantia nigra are not fully understood. In this study, N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) was injected in rats, whereafter behavior, striatal KCl-evoked dopamine and glutamate releases, and immunohistochemistry were monitored at 3 days, 3 months, and 6 months. Quantification of dopamine-beta-hydroxylase-immunoreactive nerve fiber density in the cortex revealed a tendency towards nerve fiber regeneration at 6 months. To sustain a stable noradrenergic denervation throughout the experimental timeline, the animals in the 6-month time point received an additional DSP4 injection (2 months after the first injection). Behavioral examinations utilizing rotarod revealed that DSP4 reduced the time spent on the rotarod at 3 but not at 6 months. KCl-evoked dopamine release was significantly increased at 3 days and 3 months, while the concentrations were normalized at 6 months. DSP4 treatment prolonged both time for onset and reuptake of dopamine release over time. The dopamine degeneration was confirmed by unbiased stereology, demonstrating significant loss of tyrosine hydroxylase-immunoreactive neurons in the substantia nigra. Furthermore, striatal glutamate release was decreased after DSP4. In regards of neuroinflammation, reactive microglia were found over the substantia nigra after DSP4 treatment. In conclusion, long-term noradrenergic denervation reduces the number of dopaminergic neurons in the substantia nigra and affects the functionality of the nigrostriatal system. Thus, locus coeruleus is important for maintenance of nigral dopaminergic neurons.

  • 3. Ahlén Bergman, Emma
    et al.
    Hartana, Ciputra Adijaya
    Johansson, Markus
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Urologi och andrologi. Department of Urology, Sundsvall Hospital, Sundsvall, Sweden..
    Linton, Ludvig B
    Berglund, Sofia
    Hyllienmark, Martin
    Lundgren, Christian
    Holmström, Benny
    Palmqvist, Karin
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Urologi och andrologi. Department of Surgery, Urology Section, Östersund County Hospital, Östersund, Sweden.
    Hansson, Johan
    Alamdari, Farhood
    Huge, Ylva
    Aljabery, Firas
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Winerdal, Malin E
    Krantz, David
    Zirakzadeh, A. Ali
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Urologi och andrologi. Unit of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
    Marits, Per
    Sjöholm, Louise K
    Sherif, Amir
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Urologi och andrologi. Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Winqvist, Ola
    Increased CD4+ T cell lineage commitment determined by CpG methylation correlates with better prognosis in urinary bladder cancer patients2018Ingår i: Clinical Epigenetics, E-ISSN 1868-7083, Vol. 10, artikel-id 102Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Urinary bladder cancer is a common malignancy worldwide. Environmental factors and chronic inflammation are correlated with the disease risk. Diagnosis is performed by transurethral resection of the bladder, and patients with muscle invasive disease preferably proceed to radical cystectomy, with or without neoadjuvant chemotherapy. The anti-tumour immune responses, known to be initiated in the tumour and draining lymph nodes, may play a major role in future treatment strategies. Thus, increasing the knowledge of tumour-associated immunological processes is important. Activated CD4+ T cells differentiate into four main separate lineages: Th1, Th2, Th17 and Treg, and they are recognized by their effector molecules IFN-γ, IL-13, IL-17A, and the transcription factor Foxp3, respectively. We have previously demonstrated signature CpG sites predictive for lineage commitment of these four major CD4+ T cell lineages. Here, we investigate the lineage commitment specifically in tumour, lymph nodes and blood and relate them to the disease stage and response to neoadjuvant chemotherapy.

    RESULTS: Blood, tumour and regional lymph nodes were obtained from patients at time of transurethral resection of the bladder and at radical cystectomy. Tumour-infiltrating CD4+ lymphocytes were significantly hypomethylated in all four investigated lineage loci compared to CD4+ lymphocytes in lymph nodes and blood (lymph nodes vs tumour-infiltrating lymphocytes: IFNG -4229 bp p < 0.0001, IL13 -11 bp p < 0.05, IL17A -122 bp p < 0.01 and FOXP3 -77 bp p > 0.05). Examination of individual lymph nodes displayed different methylation signatures, suggesting possible correlation with future survival. More advanced post-cystectomy tumour stages correlated significantly with increased methylation at the IFNG -4229 bp locus. Patients with complete response to neoadjuvant chemotherapy displayed significant hypomethylation in CD4+ T cells for all four investigated loci, most prominently in IFNG p < 0.0001. Neoadjuvant chemotherapy seemed to result in a relocation of Th1-committed CD4+ T cells from blood, presumably to the tumour, indicated by shifts in the methylation patterns, whereas no such shifts were seen for lineages corresponding to IL13, IL17A and FOXP3.

    CONCLUSION: Increased lineage commitment in CD4+ T cells, as determined by demethylation in predictive CpG sites, is associated with lower post-cystectomy tumour stage, complete response to neoadjuvant chemotherapy and overall better outcome, suggesting epigenetic profiling of CD4+ T cell lineages as a useful readout for clinical staging.

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  • 4.
    Ahmed, Maghfoor
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Antibiotikaanvändning före diagnos och överlevnad vidkolorektalcancer stadium IV.2022Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 5.
    Ala-Prinkkilä, Aleksi
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Explorativ analys av motorisk aktivitet under sömn på3-åriga barn2022Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 6.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Harstad, Herlof
    Haugen, Simen
    Ohberg, Lars
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Sclerosing polidocanol injections to treat chronic painful shoulder impingement syndrome-results of a two-centre collaborative pilot study.2006Ingår i: Knee Surg Sports Traumatol Arthrosc, ISSN 0942-2056, Vol. 14, nr 12, s. 1321-6Artikel i tidskrift (Refereegranskat)
  • 7.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Masci, Lorenzo
    Öhberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Partial midportion Achilles tendon ruptures: new sonographic findings helpful for diagnosis.2011Ingår i: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, nr 5, s. 429-432Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Partial Achilles tendon ruptures are not always easy to diagnose. A history including a sudden onset of pain, and/or relative weakness in plantar flexion force, are indicators. The most loaded side of the Achilles tendon is the dorsal side (skin side). OBJECTIVE: To evaluate the ultrasound (US) and Doppler (CD) findings in patients with a suspected partial rupture in the Achilles tendon. Material and METHODS: Seventeen patients (16 men and 1 woman) with a mean age of 36 years (range 23-71) were examined clinically and by US+CD because of midportion Achilles tendon pain. There was an acute onset in 14/17 patients, and all had painful weakness during tendon loading activity. RESULTS: In all patients the US examination showed a partial Achilles tendon rupture, presented as a disrupted dorsal (skin side) tendon line and an irregular tendon structure mainly located in the dorsal and mid-tendon. The size of the rupture varied from 1/3 to 2/3 of the tendon thickness. In the dorsal part of the tendon, corresponding to the region with disrupted tendon line and irregular structure, CD examination showed high blood flow-most often of a longitudinal character. Six of the patients were surgically treated, and macroscopical examination verified the ultrasound findings, showing disruption on the dorsal side, and a partial rupture in the dorsal and mid- tendon. CONCLUSIONS: Ultrasound and Doppler examination can be helpful tools to diagnose partial midportion Achilles tendon ruptures. The characteristic findings of a disrupted dorsal tendon line, and high blood flow in the structurally abnormal dorsal tendon, indicate a partial rupture.

  • 8.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Ohberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Increased intratendinous vascularity in the early period after sclerosing injection treatment in Achilles tendinosis: a healing response?2006Ingår i: Knee Surg Sports Traumatol Arthrosc, ISSN 0942-2056, Vol. 14, nr 4, s. 399-401Artikel i tidskrift (Refereegranskat)
  • 9.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Pietilä, Tom
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Öhberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Lorentzon, Ronny
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Achilles tendinosis and calf muscle strength: the effect of short-term immobilization after surgical treatment1998Ingår i: American Journal of Sports Medicine, ISSN 0363-5465, E-ISSN 1552-3365, Vol. 26, nr 2, s. 166-71Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We prospectively studied calf muscle strength in 7 men and 4 women (mean age, 40.9 +/- 10.1 years) who had surgical treatment for chronic Achilles tendinosis. Surgery was followed by immobilization in a weightbearing below-the-knee plaster cast for 2 weeks followed by a stepwise increasing strength training program. Strength measurements (peak torque and total work) were done preoperatively (Week 0) and at 16, 26, and 52 weeks postoperatively. We measured isokinetic concentric plantar flexion strength at 90 and 225 deg/sec and eccentric flexion strength at 90 deg/sec on both the injured and noninjured sides. Preoperatively, concentric and eccentric strength were significantly lower on the injured side at 90 and 225 deg/sec. Postoperatively, concentric peak torque on the injured side decreased significantly between Weeks 0 and 16 and increased significantly between Weeks 26 and 52 at 90 deg/sec but was significantly lower than that on the noninjured side at all periods and at both velocities. The eccentric strength was significantly lower on the injured side at Week 26 but increased significantly until at Week 52 no significant differences between the sides could be demonstrated. It seems, therefore, that the recovery in concentric and eccentric calf muscle strength after surgery for Achilles tendinosis is slow. We saw no obvious advantages in recovery of muscle strength with a short immobilization time (2 weeks) versus a longer (6 weeks) period used in a previous study.

  • 10.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap.
    Willberg, Lotta
    Öhberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Forsgren, Sture
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Anatomi.
    Ultrasound and doppler-guided artthroscopic shaving for the treatment of patellar tendinopathy/jumper´s knee: biological background and description of method2011Ingår i: Anterior knee pain and patellar instability / [ed] Sanchis-Alfonso, Vicente, London: Springer London, 2011, s. 367-371Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Treatment with ultrasound and Doppler-guided arthroscopic shaving of the region with vessels and nerves outside the dorsal tendon has shown promising clinical results in patients with proximal patellar tendinopathy/Jumper´s knee. The results concerning only a limited patient material has been published in a scientific paper. Results on larger materials are under evaluation for later publication. Proper understanding of the ultrasound and Doppler findings, to enable for a precise and minimal arthroscopic shaving procedure on the dorsal side of the tendon, are cornerstones using this new type of treatment.

  • 11.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Öhberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Neovascularisation in chronic painful patellar tendinosis - promising results after sclerosing neovessels outside the tendon challenge the need for surgery2005Ingår i: Knee Surg Sports Traumatol Arthrosc, ISSN 0942-2056, Vol. 13, nr 2, s. 74-80Artikel i tidskrift (Refereegranskat)
  • 12.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Öhberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Sclerosing injections to areas of neo-vascularisation reduce pain in chronic Achilles tendinopathy: a double-blind randomised controlled trial2005Ingår i: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 13, nr 4, s. 338-344Artikel i tidskrift (Refereegranskat)
  • 13.
    Alfredson, Håkan
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Öhberg, Lars
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Zeisig, Ewa
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Lorentzon, Ronny
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Treatment of midportion Achilles tendinosis: similar clinical results with US and CD-guided surgery outside the tendon and sclerosing polidocanol injections.2007Ingår i: Knee Surg Sports Traumatol Arthrosc, ISSN 0942-2056, Vol. 15, nr 12, s. 1504-1509Artikel i tidskrift (Refereegranskat)
  • 14.
    Alkstedt, Karl
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Respiratory gated PET/CT in lung cancer, a comparison with static PET/CT2012Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 15. Allocca, Giancarlo
    et al.
    Ma, Sherie
    Martelli, Davide
    Cerri, Matteo
    Del Vecchio, Flavia
    Bastianini, Stefano
    Zoccoli, Giovanna
    Amici, Roberto
    Morairty, Stephen R.
    Aulsebrook, Anne E.
    Blackburn, Shaun
    Lesku, John A.
    Rattenborg, Niels C.
    Vyssotski, Alexei L.
    Wams, Emma
    Porcherer, Kate
    Wulff, Katharina
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten). Centre for Molecular Medicine (WCMM), Umeå University, Sweden.
    Foster, Russell
    Chan, Julia K. M.
    Nicholas, Christian L.
    Freestone, Dean R.
    Johnston, Leigh A.
    Gundlachla, Andrew L.
    Validation of 'Somnivore', a Machine Learning Algorithm for Automated Scoring and Analysis of Polysomnography Data2019Ingår i: Frontiers in Neuroscience, ISSN 1662-4548, E-ISSN 1662-453X, Vol. 13, artikel-id 207Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Manual scoring of polysomnography data is labor-intensive and time-consuming, and most existing software does not account for subjective differences and user variability. Therefore, we evaluated a supervised machine learning algorithm, Somnivore (TM), for automated wake-sleep stage classification. We designed an algorithm that extracts features from various input channels, following a brief session of manual scoring, and provides automated wake-sleep stage classification for each recording. For algorithm validation, polysomnography data was obtained from independent laboratories, and include normal, cognitively-impaired, and alcohol-treated human subjects (total n = 52), narcoleptic mice and drug-treated rats (total n = 56), and pigeons (n = 5). Training and testing sets for validation were previously scored manually by 1-2 trained sleep technologists from each laboratory. F-measure was used to assess precision and sensitivity for statistical analysis of classifier output and human scorer agreement. The algorithm gave high concordance with manual visual scoring across all human data (wake 0.91 +/- 0.01; N1 0.57 +/- 0.01; N2 0.81 +/- 0.01; N3 0.86 +/- 0.01; REM 0.87 +/- 0.01), which was comparable to manual inter-scorer agreement on all stages. Similarly, high concordance was observed across all rodent (wake 0.95 +/- 0.01; NREM 0.94 +/- 0.01; REM 0.91 +/- 0.01) and pigeon (wake 0.96 +/- 0.006; NREM 0.97 +/- 0.01; REM 0.86 +/- 0.02) data. Effects of classifier learning from single signal inputs, simple stage reclassification, automated removal of transition epochs, and training set size were also examined. In summary, we have developed a polysomnography analysis program for automated sleep-stage classification of data from diverse species. Somnivore enables flexible, accurate, and high-throughput analysis of experimental and clinical sleep studies.

  • 16.
    Ambarki, Khalid
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Hallberg, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Jóhannesson, Gauti
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Lindén, Christina
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Zarrinkoob, Laleh
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Wåhlin, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Birgander, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Malm, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Eklund, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Blood flow of ophthalmic artery in healthy individuals determined by phase-contrast magnetic resonance imaging2013Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 54, nr 4, s. 2738-2745Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: Recent development of magnetic resonance imaging (MRI) offers new possibilities to assess ocular blood flow. This prospective study evaluates the feasibility of phase-contrast MRI (PCMRI) to measure flow rate in the ophthalmic artery (OA) and establish reference values in healthy young (HY) and elderly (HE) subjects.

    METHODS: Fifty HY subjects (28 females, 21-30 years of age) and 44 HE (23 females, 64-80 years of age) were scanned on a 3-Tesla MR system. The PCMRI sequence had a spatial resolution of 0.35 mm per pixel, with the measurement plan placed perpendicularly to the OA. Mean flow rate (Qmean), resistive index (RI), and arterial volume pulsatility of OA (ΔVmax) were measured from the flow rate curve. Accuracy of PCMRI measures was investigated using a vessel-phantom mimicking the diameter and the flow rate range of the human OA.

    RESULTS: Flow rate could be assessed in 97% of the OAs. Phantom investigations showed good agreement between the reference and PCMRI measurements with an error of <7%. No statistical difference was found in Qmean between HY and HE individuals (HY: mean ± SD = 10.37 ± 4.45 mL/min; HE: 10.81 ± 5.15 mL/min, P = 0.655). The mean of ΔVmax (HY: 18.70 ± 7.24 μL; HE: 26.27 ± 12.59 μL, P < 0.001) and RI (HY: 0.62 ± 0.08; HE: 0.67 ± 0.1, P = 0.012) were significantly different between HY and HE.

    CONCLUSIONS: This study demonstrated that the flow rate of OA can be quantified using PCMRI. There was an age difference in the pulsatility parameters; however, the mean flow rate appeared independent of age. The primary difference in flow curves between HE and HY was in the relaxation phase of the systolic peak.

  • 17.
    Ambarki, Khalid
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Israelsson, Hanna
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Neurologi.
    Wåhlin, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Birgander, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Eklund, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Malm, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Neurologi.
    Brain ventricular size in healthy elderly: comparison between evans index and volume measurement.2010Ingår i: Neurosurgery, ISSN 0148-396X, E-ISSN 1524-4040, Vol. 67, nr 1, s. 94-99Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: A precise definition of ventricular enlargement is important in the diagnosis of hydrocephalus as well as in assessing central atrophy. The Evans index (EI), a linear ratio between the maximal frontal horn width and the cranium diameter, has been extensively used as an indirect marker of ventricular volume (VV). With modern imaging techniques, brain volume can be directly measured. OBJECTIVE: To determine reference values of intracranial volumes in healthy elderly individuals and to correlate volumes with the EI. METHODS: Magnetic resonance imaging (3 T) was performed in 46 healthy white elderly subjects (mean age +/- standard deviation, 71 +/- 6 years) and in 20 patients (74 +/- 7 years) with large ventricles according to visual inspection. VV, relative VV (RVV), and EI were assessed. Ventricular dilation was defined using VV and EI by a value above the 95th percentile range for healthy elderly individuals. RESULTS: In healthy elderly subjects, we found VV = 37 +/- 18 mL, RVV = 2.47 +/- 1.17%, and EI = 0.281 +/- 0.027. Including the patients, there was a strong correlation between EI and VV (R = 0.94) as well as between EI and RVV (R = 0.95). However, because of a wide 95% prediction interval (VV: +/-45 mL; RVV: +/- 2.54%), EI did not give a sufficiently good estimate of VV and RVV. CONCLUSION: VV (or RVV) and the EI reflect different properties. The exclusive use of EI in clinical studies as a marker of enlarged ventricles should be questioned. We suggest that the definition of dilated ventricles in white elderly individuals be defined as VV >77 mL or RVV >4.96 %. Future studies should compare intracranial volumes with clinical characteristics and prognosis.

  • 18.
    Ambarki, Khalid
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Centrum för medicinsk teknik och fysik (CMTF).
    Lindqvist, Tomas
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Centrum för medicinsk teknik och fysik (CMTF).
    Wåhlin, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Centrum för medicinsk teknik och fysik (CMTF).
    Petterson, E
    Warntjes, JBM
    Birgander, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Malm, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Eklund, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Centrum för medicinsk teknik och fysik (CMTF).
    Evaluation of automatic measurement of the intracranial volume based on quantitative MR imaging2012Ingår i: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 33, nr 10, s. 1951-1956Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND AND PURPOSE: Brain size is commonly described in relation to ICV, whereby accurate assessment of this quantity is fundamental. Recently, an optimized MR sequence (QRAPMASTER) was developed for simultaneous quantification of T1, T2, and proton density. ICV can be measured automatically within minutes from QRAPMASTER outputs and a dedicated software, SyMRI. Automatic estimations of ICV were evaluated against the manual segmentation.

    MATERIALS AND METHODS: In 19 healthy subjects, manual segmentation of ICV was performed by 2 neuroradiologists (Obs1, Obs2) by using QBrain software and conventional T2-weighted images. The automatic segmentation from the QRAPMASTER output was performed by using SyMRI. Manual corrections of the automatic segmentation were performed (corrected-automatic) by Obs1 and Obs2, who were blinded from each other. Finally, the repeatability of the automatic method was evaluated in 6 additional healthy subjects, each having 6 repeated QRAPMASTER scans. The time required to measure ICV was recorded.

    RESULTS: No significant difference was found between reference and automatic (and corrected-automatic) ICV (P > .25). The mean difference between the reference and automatic measurement was -4.84 ± 19.57 mL (or 0.31 ± 1.35%). Mean differences between the reference and the corrected-automatic measurements were -0.47 ± 17.95 mL (-0.01 ± 1.24%) and -1.26 ± 17.68 mL (-0.06 ± 1.22%) for Obs1 and Obs2, respectively. The repeatability errors of the automatic and the corrected-automatic method were <1%. The automatic method required 1 minute 11 seconds (SD = 12 seconds) of processing. Adding manual corrections required another 1 minute 32 seconds (SD = 38 seconds).

    CONCLUSIONS: Automatic and corrected-automatic quantification of ICV showed good agreement with the reference method. SyMRI software provided a fast and reproducible measure of ICV.

  • 19.
    Ambarki, Khalid
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Wåhlin, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Birgander, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Eklund, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Malm, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    MR imaging of brain volumes: evaluation of a fully automatic software2011Ingår i: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 32, nr 2, s. 408-412Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND AND PURPOSE: Automatic assessment of brain volumes is needed in researchand clinical practice. Manual tracing is still the criterionstandard but is time-consuming. It is important to validatethe automatic tools to avoid the problems of clinical studiesdrawing conclusions on the basis of brain volumes estimatedwith methodologic errors. The objective of this study was toevaluate a new commercially available fully automatic softwarefor MR imaging of brain volume assessment. Automatic and expertmanual brain volumes were compared.

    MATERIALS AND METHODS: MR imaging (3T, axial T2 and FLAIR) was performed in 41 healthyelderly volunteers (mean age, 70 ± 6 years) and 20 patientswith hydrocephalus (mean age, 73 ± 7 years). The softwareQBrain was used to manually and automatically measure the followingbrain volumes: ICV, BTV, VV, and WMHV. The manual method hasbeen previously validated and was used as the reference. Agreementbetween the manual and automatic methods was evaluated by usinglinear regression and Bland-Altman plots.

    RESULTS: There were significant differences between the automatic andmanual methods regarding all volumes. The mean differences wereICV = 49 ± 93 mL (mean ± 2SD, n = 61), BTV = 11± 70 mL, VV = –6 ± 10 mL, and WMHV = 2.4± 9 mL. The automatic calculations of brain volumes tookapproximately 2 minutes per investigation.

    CONCLUSIONS: The automatic tool is promising and provides rapid assessmentof brain volumes. However, the software needs improvement beforeit is incorporated into research or daily use. Manual segmentationremains the reference method.

  • 20. Andersson, Elisabeth
    et al.
    Dai Ydrefelt, Ying
    Johannesson, Marit
    Lundbäck, Maria
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Mannila, Maria
    Persson, Margaretha
    Swahn, Eva
    Bolejko, Anetta
    Surveillance of indeterminate pulmonary nodules detected with CT in a Swedish population-based study (SCAPIS): Psychosocial consequences and impact on health-related quality of life - A multicentre prospective cross-sectional study2021Ingår i: BMJ Open, E-ISSN 2044-6055, Vol. 11, nr 9, artikel-id e048721Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives: To investigate whether surveillance of pulmonary nodules detected with low-dose CT (LDCT) impacted health-related quality of life and psychosocial consequences in the Swedish population-based study, Swedish CArdioPulmonary bioImage Study (SCAPIS).

    Design: A prospective cross-sectional study.

    Settings and participants: This multicentre (five sites) observational study, which included a cohort from SCAPIS, consisted of 632 participants with indeterminate pulmonary nodules detected with LDCT. These participants continued surveillance for up to 36 months, during which lung cancer was not detected (surveillance group). Additionally, 972 participants with a negative pulmonary LDCT scan were included as a control group. Matching criteria were LDCT date (±2 weeks), gender and site.

    Outcome measures: All participants completed a health-related quality of life questionnaire (RAND-36) and the Consequences of Screening (COS) questionnaire, an average of 3 years after LDCT was conducted at entry into SCAPIS.

    Results: Participants were 51-70 years old at study commencement. Overall, the two groups did not differ in demographic or psychosocial variables, smoking habits or pulmonary medical history. Individuals from countries other than Sweden and those with low socioeconomic status were less likely to participate (p<0.001). No effects on health-related quality of life were observed via RAND-36. In COS, the surveillance group demonstrated a higher OR for anxiety about lung cancer (OR 3.96, 95% CI 2.35 to 6.66, p<0.001), experiencing a sense of dejection (OR 1.35, 95% CI 1.06 to 1.72, p=0.015) and thoughts about existential values (OR 1.30, 95% CI 1.04 to 1.60, p=0.018).

    Conclusions: Lung surveillance with LDCT contributed to significant experiences of sense of dejection, anxiety about lung cancer and development of thoughts about existential values among participants in the surveillance group compared with the controls. The risk of side effects should be communicated for informed decision-making about (non-)attendance in lung cancer screening.

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  • 21.
    Andersson, Jonas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Granberg, Christoffer
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    A novel system for quality assurance of radiology equipment2018Ingår i: EuroSafe Imaging 2018 / ESI-0064, EuroSafe Imaging , 2018Konferensbidrag (Refereegranskat)
  • 22.
    Andersson, Jonas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Karpe, Fredrik
    NIHR Oxford Biomedical Research Centre, Churchill Hospital, Oxford, UK.
    Sjöström, Lars-Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Söderberg, Stefan
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Olsson, Tommy
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Association of adipose tissue blood flow with fat depot sizes and adipokines in women2012Ingår i: International Journal of Obesity, ISSN 0307-0565, E-ISSN 1476-5497, Vol. 36, nr 6, s. 783-789Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: To explore possible associations between adipose tissue (AT) blood flow (ATBF), AT depot sizes and adipocyte-derived hormones (adipokines) in women.

    Subjects: In all, 43 healthy women were divided into four groups: normal-weight (n=11) and obese (n=11) pre-menopausal women and normal-weight (n=10) and obese (n=11) post-menopausal women.

    Methods: Fasting levels of adipokines were obtained, and a single-slice computed tomography scan at the level of L4-L5 was used to estimate fat depot sizes. ATBF was assessed by xenon washout while in a fasting state and after oral glucose load. We also measured glucose, insulin and non-esterified fatty acids.

    Results: Total, subcutaneous and visceral AT areas strongly correlated with ATBF (all P<0.001). Circulating leptin levels strongly and inversely correlated with ATBF (P=0.001), but this association did not remain after adjustment for body mass index. Adiponectin was not associated with blood flow.

    Conclusion: ATBF is closely linked to subcutaneous and visceral AT size. Further analyses are needed to determine possible mediators of this association, including mechanistic studies to assess a putative role for leptin as a significant modulator of blood flow. International Journal of Obesity advance online publication, 26 July 2011; doi:10.1038/ijo.2011.152.

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  • 23.
    Andersson, Linus
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Claesson, Anna-Sara
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi. Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Stenberg, Berndt
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Dermatologi och venereologi.
    Nordin, Steven
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Brain responses to olfactory and trigeminal exposure in idiopathic environmental illness (IEI) attributed to smells: An fMRI study2014Ingår i: Journal of Psychosomatic Research, ISSN 0022-3999, E-ISSN 1879-1360, Vol. 77, nr 5, s. 401-408Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: Idiopathic environmental intolerance (IEI) to smells is a prevalent medically unexplained illness. Sufferers attribute severe symptoms to low doses of non-toxic chemicals. Despite the label, IEI is not characterized by acute chemical senses. Theoretical models suggest that sensitized responses in the limbic system of the brain constitute an important mechanism behind the symptoms. The aim was to investigate whether and how brain reactions to low-levels of olfactory and trigeminal stimuli differ in individuals with and without IEI. METHODS: Brain responses to intranasally delivered isoamyl acetate and carbon dioxide were assessed in 25 women with IEI and 26 non-ill controls using functional magnetic resonance imaging. RESULTS: The IEI group had higher blood-oxygenated-level-dependent (BOLD) signal than controls in the thalamus and a number of, mainly, parietal areas, and lower BOLD signal in the superior frontal gyrus. The IEI group did not rate the exposures as more intense than the control group did, and there were no BOLD signal differences between groups in the piriform cortex or olfactory regions of the orbitofrontal cortex. CONCLUSIONS: The IEI reactions were not characterized by hyper-responsiveness in sensory areas. The results can be interpreted as a limbic hyperreactivity and speculatively as an inability to inhibit salient extemal stimuli.

  • 24.
    Andersson, Linus
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Eriksson, Johan
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Stillesjö, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Juslin, Peter
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Karlsson Wirebring, Linnea
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Neurocognitive processes underlying heuristic and normative probability judgments2020Ingår i: Cognition, ISSN 0010-0277, E-ISSN 1873-7838, Vol. 196, s. 1-7, artikel-id 104153Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Judging two events in combination (A&B) as more probable than one of the events (A) is known as a conjunction fallacy. According to dual-process explanations of human judgment and decision making, the fallacy is due to the application of a heuristic, associative cognitive process. Avoiding the fallacy has been suggested to require the recruitment of a separate process that can apply normative rules. We investigated these assumptions using functional magnetic resonance imaging (fMRI) during conjunction tasks. Judgments, whether correct or not, engaged a network of brain regions identical to that engaged during similarity judgments. Avoidance of the conjunction fallacy additionally, and uniquely, involved a fronto-parietal network previously linked to supervisory, analytic control processes. The results lend credibility to the idea that incorrect probability judgments are the result of a representativeness heuristic that requires additional neurocognitive resources to avoid.

  • 25.
    Andersson, Linus
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Sandberg, Petra
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Åström, Elisabeth
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Lillqvist, Moa
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Claeson, Anna-Sara
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Chemical Intolerance Is Associated With Altered Response Bias, not Greater Sensory Sensitivity2020Ingår i: i-Perception, E-ISSN 2041-6695, Vol. 11, nr 6, artikel-id 2041669520978424Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chemical intolerance is a surprisingly prevalent condition or affliction characterized by adverse reactions to low levels of chemical, often odorous stimulation. Sufferers often assume that their plight is due to an uncommon sensory acuteness, yet studies repeatedly fail to reveal altered detection thresholds. Here, we investigated whether self-reported chemical intolerance is associated with altered sensory sensitivity or response bias. The sensory acuity (sensitivity; A) and sensory decision rule (criterion; B) to n-butanol was assessed using the method of constant stimuli in 82 participants with different degrees of chemical intolerance (low to high). Higher self-reported chemical intolerance was associated with a lower criterion, but not with sensitivity.

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  • 26.
    Andersson, Ronny
    et al.
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Onkologi.
    Hofer, Åke
    Umeå universitet, Medicinsk fakultet, Folkhälsa och klinisk medicin, Dermatologi och venereologi.
    Riklund-Åhlström, Katrine
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Henriksson, Roger
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Onkologi.
    Effects of interferon-[alpha], verapamil and dacarbazine in the treatment of advanced malignant melanoma2003Ingår i: Melanoma research, ISSN 0960-8931, E-ISSN 1473-5636, Vol. 13, nr 1, s. 87-91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Treatment of patients with metastatic melanoma with either dacarbazine (DTIC) or interferon-[alpha] (IFN[alpha]) as single drugs, or in combination, results in a response rate of approximately 15–20%. This study evaluated the activity and toxicity following treatment with a combination of DTIC, IFN[alpha]2b and verapamil (VPL). Thirty patients with disseminated metastatic melanoma received DTIC 250 mg/m2 on days 1–5 of a 4 week schedule, IFN[alpha]2b 3 MIU on days 1–5 each week, and VPL 80 mg three times a day throughout the cycle, until either disease progression or serious toxicity was observed. Among the 28 evaluable patients, there were four complete responses (CRs), five partial responses (PRs) and eight patients with stable disease (SD). The overall response rate (CR + PR) was 32%. Two patients with a CR were long-term survivors (45 and 34 months) and a third is still in complete remission after 49 months. The fourth CR patient relapsed and died with progressive brain metastases after 8 months. Among the eight patients with SD, one survived for 22 months and another for 34 months. Despite one toxic death, these results suggest that this treatment regimen is well tolerated and seems to be more effective than DTIC alone in a subset of patients. A controlled randomized study would be required to determine the value of adding VPL and IFN[alpha]2b to DTIC.

  • 27.
    Andersson, Sara
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå University Hospital.
    Josefsson, Maria
    Umeå universitet, Samhällsvetenskapliga fakulteten, Handelshögskolan vid Umeå universitet, Statistik. Umeå universitet, Samhällsvetenskapliga fakulteten, Enheten för demografi och åldrandeforskning (CEDAR).
    Stiernman, Lars J.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Rieckmann, Anna
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Center for the Economics of Aging, Max Planck Institute for Social Law and Social Policy, Germany.
    Cognitive decline in Parkinson’s disease: a subgroup of extreme decliners revealed by a data-driven analysis of longitudinal progression2021Ingår i: Frontiers in Psychology, E-ISSN 1664-1078, Vol. 12, artikel-id 729755Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cognitive impairment is an important symptom of Parkinson’s disease (PD) and predicting future cognitive decline is crucial for clinical practice. Here, we aim to identify latent sub-groups of longitudinal trajectories of cognitive change in PD patients, and explore predictors of differences in cognitive change. Longitudinal cognitive performance data from 349 newly diagnosed PD patients and 145 healthy controls from the Parkinson Progression Marker Initiative were modeled using a multivariate latent class linear mixed model. Resultant latent classes were compared on a number of baseline demographics, and clinical variables, as well as cerebrospinal fluid (CSF) biomarkers and striatal dopamine transporter (DAT) density markers of neuropathology. Trajectories of cognitive change in PD were best described by two latent classes. A large subgroup (90%), which showed a subtle impairment in cognitive performance compared to controls but remained stable over the course of the study, and a small subgroup (10%) which rapidly declined in all cognitive performance measures. Rapid decliners did not differ significantly from the larger group in terms of disease duration, severity or motor symptoms at baseline. However, rapid decliners had lower CSF amyloidß42 levels, a higher prevalence of sleep disorder and pronounced loss of caudate DAT density at baseline. These data suggest the existence of a distinct minority sub-type of PD in which rapid cognitive change in PD can occur uncoupled from motor symptoms or disease severity, likely reflecting early pathological change that extends from motor areas of the striatum into associative compartments and cortex.

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  • 28. Arheden, Håkan
    et al.
    Aspelin, Peter
    Bajc, Marika
    Damm, Sabine
    Flodmark, Olof
    Friberg, Peter
    Gustafsson, Lars
    Holtås, Stig
    Modin, Agnes
    Riklund, Katrine
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Rydh, Anders
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Functional imaging medicine: a new specialty with great prospects2006Ingår i: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 103, nr 39, s. 2883-2884Artikel i tidskrift (Refereegranskat)
  • 29.
    Arnerlöv, Conny
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Söderström, Minette
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Öhberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Mobile kidney pain provocation ultrasonography before surgery for symptomatic mobile kidney: A prospective study of 43 consecutive patients2016Ingår i: Scandinavian journal of urology, ISSN 2168-1805, E-ISSN 2168-1813, Vol. 50, nr 1, s. 61-64Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: The aim of this study was to evaluate whether mobile kidney pain provocation ultrasonography together with intravenous pyelography in supine and standing positions and a full medical history can confirm the diagnosis of the clinical condition of symptomatic mobile kidney and aid the selection of patients for surgical treatment.

    MATERIALS AND METHODS: In a consecutive study, 43 patients with the clinical picture of symptomatic mobile kidney, a positive mobile kidney pain provocation ultrasonography and a renal descent of at least 2 lumbar vertebral heights on intravenous pyelography in the standing position, were operated on with nephropexy. Patients' pain relief after nephropexy was evaluated by clinical follow-up, a questionnaire and visual analogue scale (VAS) scoring.

    RESULTS: Reduction of pain after nephropexy was associated with a significant decrease in VAS scoring from a median of 8 (range 4-10) preoperatively to a median of 0 (range 0-7) postoperatively (p < 0.001). Thirty-four patients (79%) were cured of their pain and seven patients (16%) experienced substantial relief from their pain symptoms. In two patients (5%) the symptoms were unchanged.

    CONCLUSION: The results indicate that mobile kidney pain provocation ultrasonography and intravenous pyelography in supine and standing positions can verify the diagnosis of symptomatic mobile kidney and aid the selection of patients who will benefit from nephropexy.

  • 30.
    Arnerlöv, Conny
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Öhberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Ghaffarpour, Ramin
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Urologi och andrologi.
    Trippeldiagnostik säker vid symtomgivande rörlig njure: [Triple diagnostic can establish the diagnosis of symptomatic mobile kidney and nephropexy can give freedom of pain]2020Ingår i: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 117, nr 37, artikel-id 20025Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Symtomatic mobile kidney is a rare condition and diagnosis is difficult. Typical symptoms are position dependent back-flank-abdominal pain with increase of pain when walking, jogging and lifting or other physical activities which increase the descent of the kidney. Triple diagnostic with typical pain history, an intravenous pyelography with a renal descent of ≥ 2 lumbar vertebral heights in the erect position, and an ultrasound with a positive pain provocation can establish the diagnosis of symptomatic mobile kidney. In our study nephropexy gives freedom of pain for 75% of patients and substantial relief for 15% of patients with severe pain.

  • 31.
    Asklund, Thomas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Henriksson, Roger
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Bergström, Åsa
    Kasper, Maria
    Ögren, Margareta
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Toftgård, Rune
    Riklund, Katrine Åhlström
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Early and persisting response to vismodegib in a patient with bone metastasizing medulloblastoma2013Ingår i: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 52, nr 4, s. 862-865Artikel i tidskrift (Refereegranskat)
  • 32.
    Asklund, Thomas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Sandström, Maria
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Shahidi, Saeed
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Henriksson, Roger
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Durable stabilization of three chordoma cases by bevacizumab and erlotinib2014Ingår i: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 53, nr 7, s. 980-984Artikel i tidskrift (Refereegranskat)
  • 33.
    Avelar-Pereira, Barbara
    et al.
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
    Bäckman, Lars
    Wåhlin, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Salami, Alireza
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
    Increased functional homotopy of the prefrontal cortex is associated with corpus callosum degeneration and working memory decline2020Ingår i: Neurobiology of Aging, ISSN 0197-4580, E-ISSN 1558-1497, Vol. 96, s. 68-78Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Functional homotopy reflects the link between spontaneous activity in a voxel and its counterpart in the opposite hemisphere. Alterations in homotopic functional connectivity (FC) are seen in normal aging, with highest and lowest homotopy being present in sensory-motor and higher-order regions, respectively. Homotopic FC relates to underlying structural connections, but its neurobiological underpinnings remain unclear. The genu of the corpus callosum joins symmetrical parts of the prefrontal cortex (PFC) and is susceptible to age-related degeneration, suggesting that PFC homotopic connectivity is linked to changes in white-matter integrity. We investigated homotopic connectivity changes and whether these were associated with white-matter integrity in 338 individuals. In addition, we examined whether PFC homotopic FC was related to changes in the genu over 10 years and working memory over 5 years. There were increases and decreases in functional homotopy, with the former being prevalent in subcortical and frontal regions. Increased PFC homotopic FC was partially driven by structural degeneration and negatively associated with working memory, suggesting that it reflects detrimental age-related changes. (C) 2020 The Author(s). Published by Elsevier Inc.

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  • 34.
    Backeström, Anna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Allmänmedicin.
    Papadopoulos, Konstantin
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Allmänmedicin.
    Eriksson, Sture
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Näringsforskning.
    Olsson, Tommy
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för medicin.
    Andersson, Micael
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Blennow, Kaj
    Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at University of Gothenburg, Mö lndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mö lndal, Sweden.
    Zetterberg, Henrik
    Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mö lndal, Sweden; Department of Neurodegenerative Disease, Ucl Institute of Neurology, Queen Square, London, United Kingdom; UK Dementia Research Institute at Ucl, London, United Kingdom.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Rolandsson, Olov
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Allmänmedicin.
    Acute hyperglycaemia leads to altered frontal lobe brain activity and reduced working memory in type 2 diabetes2021Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 16, nr 3, artikel-id e0247753Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    How acute hyperglycaemia affects memory functions and functional brain responses in individuals with and without type 2 diabetes is unclear. Our aim was to study the association between acute hyperglycaemia and working, semantic, and episodic memory in participants with type 2 diabetes compared to a sex- A nd age-matched control group. We also assessed the effect of hyperglycaemia on working memory-related brain activity. A total of 36 participants with type 2 diabetes and 34 controls (mean age, 66 years) underwent hyperglycaemic clamp or placebo clamp in a blinded and randomised order. Working, episodic, and semantic memory were tested. Overall, the control group had higher working memory (mean z-score 33.15 ± 0.45) than the group with type 2 diabetes (mean z-score 31.8 ± 0.44, p = 0.042) considering both the placebo and hyperglycaemic clamps. Acute hyperglycaemia did not influence episodic, semantic, or working memory performance in either group. Twenty-two of the participants (10 cases, 12 controls, mean age 69 years) were randomly invited to undergo the same clamp procedures to challenge working memory, using 1-, 2-, and 3-back, while monitoring brain activity by blood oxygen level-dependent functional magnetic resonance imaging (fMRI). The participants with type 2 diabetes had reduced working memory during the 1- A nd 2-back tests. fMRI during placebo clamp revealed increased BOLD signal in the left lateral frontal cortex and the anterior cingulate cortex as a function of working memory load in both groups (3>2>1). During hyperglycaemia, controls showed a similar load-dependent fMRI response, whereas the type 2 diabetes group showed decreased BOLD response from 2-to 3-back. These results suggest that impaired glucose metabolism in the brain affects working memory, possibly by reducing activity in important frontal brain areas in persons with type 2 diabetes.

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  • 35.
    Backman, Lars
    et al.
    Aging Research Center, Karolinska Institute and University of Stockholm, Stockholm,.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Dopamine and training-related working-memory improvement2013Ingår i: Neuroscience and Biobehavioral Reviews, ISSN 0149-7634, E-ISSN 1873-7528, Vol. 37, nr 9, s. 2209-2219Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Converging evidence indicates that the neurotransmitter dopamine (DA) is implicated in working-memory (WM) functioning and that WM is trainable. We review recent work suggesting that DA is critically involved in the ability to benefit from WM interventions. Functional MRI studies reveal increased striatal BOLD activity following certain forms of WM interventions, such as updating training. Increased striatal BOLD activity has also been linked to transfer of learning to non-trained WM tasks, suggesting a neural signature of transfer. The striatal BOLD signal is partly determined by DA activity. Consistent with this assertion, PET research demonstrates increased striatal DA release during updating of information in WM after training. Genetic studies indicate larger increases in WM performance post training for those who carry advantageous alleles of DA-relevant genes. These patterns of results corroborate the role of DA in WM improvement. Future research avenues include: (a) neuromodulatory correlates of transfer; (b) the potential of WM training to enhance DA release in older adults; (c) comparisons among different WM processes (i.e., updating, switching, inhibition) regarding regional patterns of training-related DA release; and (d) gene-gene interactions in relation to training-related WM gains.

  • 36. Bailey, D. L.
    et al.
    Pichler, B. J.
    Gueckel, B.
    Antoch, G.
    Barthel, H.
    Bhujwalla, Z. M.
    Biskup, S.
    Biswal, S.
    Bitzer, M.
    Boellaard, R.
    Braren, R. F.
    Brendle, C.
    Brindle, K.
    Chiti, A.
    la Fougere, C.
    Gillies, R.
    Goh, V.
    Goyen, M.
    Hacker, M.
    Heukamp, L.
    Knudsen, G. M.
    Krackhardt, A. M.
    Law, I.
    Morris, J. C.
    Nikolaou, K.
    Nuyts, J.
    Ordonez, A. A.
    Pantel, K.
    Quick, H. H.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Sabri, O.
    Sattler, B.
    Troost, E. G. C.
    Zaiss, M.
    Zender, L.
    Beyer, Thomas
    Combined PET/MRI: Global Warming-Summary Report of the 6th International Workshop on PET/MRI, March 27-29, 2017, Tubingen, Germany2018Ingår i: Molecular Imaging and Biology, ISSN 1536-1632, E-ISSN 1860-2002, Vol. 20, nr 1, s. 4-20Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The 6th annual meeting to address key issues in positron emission tomography (PET)/magnetic resonance imaging (MRI) was held again in Tubingen, Germany, from March 27 to 29, 2017. Over three days of invited plenary lectures, round table discussions and dialogue board deliberations, participants critically assessed the current state of PET/MRI, both clinically and as a research tool, and attempted to chart future directions. The meeting addressed the use of PET/MRI and workflows in oncology, neurosciences, infection, inflammation and chronic pain syndromes, as well as deeper discussions about how best to characterise the tumour microenvironment, optimise the complementary information available from PET and MRI, and how advanced data mining and bioinformatics, as well as information from liquid biomarkers (circulating tumour cells and nucleic acids) and pathology, can be integrated to give a more complete characterisation of disease phenotype. Some issues that have dominated previous meetings, such as the accuracy of MR-based attenuation correction (AC) of the PET scan, were finally put to rest as having been adequately addressed for the majority of clinical situations. Likewise, the ability to standardise PET systems for use in multicentre trials was confirmed, thus removing a perceived barrier to larger clinical imaging trials. The meeting openly questioned whether PET/MRI should, in all cases, be used as a whole-body imaging modality or whether in many circumstances it would best be employed to give an in-depth study of previously identified disease in a single organ or region. The meeting concluded that there is still much work to be done in the integration of data from different fields and in developing a common language for all stakeholders involved. In addition, the participants advocated joint training and education for individuals who engage in routine PET/MRI. It was agreed that PET/MRI can enhance our understanding of normal and disrupted biology, and we are in a position to describe the in vivo nature of disease processes, metabolism, evolution of cancer and the monitoring of response to pharmacological interventions and therapies. As such, PET/MRI is a key to advancing medicine and patient care.

  • 37. Bailey, D. L.
    et al.
    Pichler, B. J.
    Gueckel, B.
    Barthel, H.
    Beer, A. J.
    Botnar, R.
    Gillies, R.
    Goh, V.
    Gotthardt, M.
    Hicks, R. J.
    Lanzenberger, R.
    la Fougere, C.
    Lentschig, M.
    Nekolla, S. G.
    Niederdraenk, T.
    Nikolaou, K.
    Nuyts, J.
    Olego, D.
    Åhlstrom Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Signore, A.
    Schaefers, M.
    Sossi, V.
    Suminski, M.
    Veit-Haibach, P.
    Umutlu, L.
    Wissmeyer, M.
    Beyer, T.
    Combined PET/MRI: from Status Quo to Status Go. Summary Report of the Fifth International Workshop on PET/MR Imaging; February 15-19, 2016; Tubingen, Germany2016Ingår i: Molecular Imaging and Biology, ISSN 1536-1632, E-ISSN 1860-2002, Vol. 18, nr 5, s. 637-650Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article provides a collaborative perspective of the discussions and conclusions from the fifth international workshop of combined positron emission tomorgraphy (PET)/magnetic resonance imaging (MRI) that was held in Tubingen, Germany, from February 15 to 19, 2016. Specifically, we summarise the second part of the workshop made up of invited presentations from active researchers in the field of PET/MRI and associated fields augmented by round table discussions and dialogue boards with specific topics. This year, this included practical advice as to possible approaches to moving PET/MRI into clinical routine, the use of PET/MRI in brain receptor imaging, in assessing cardiovascular diseases, cancer, infection, and inflammatory diseases. To address perceived challenges still remaining to innovatively integrate PET and MRI system technologies, a dedicated round table session brought together key representatives from industry and academia who were engaged with either the conceptualisation or early adoption of hybrid PET/MRI systems. Discussions during the workshop highlighted that emerging unique applications of PET/MRI such as the ability to provide multi-parametric quantitative and visual information which will enable not only overall disease detection but also disease characterisation would eventually be regarded as compelling arguments for the adoption of PET/MR. However, as indicated by previous workshops, evidence in favour of this observation is only growing slowly, mainly due to the ongoing inability to pool data cohorts from independent trials as well as different systems and sites. The participants emphasised that moving from status quo to status go entails the need to adopt standardised imaging procedures and the readiness to act together prospectively across multiple PET/MRI sites and vendors.

  • 38.
    Bergdahl, Jan
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Nilsson, Lars-Göran
    Riklund Åhlström, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Nyberg, Lars
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Treatment of chronic stress in employees: subjective, cognitive and neural correlates2005Ingår i: Scandinavian Journal of Psychology, ISSN 0036-5564, E-ISSN 1467-9450, Vol. 46, nr 5, s. 395-402Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study reports the effect of an affect-focused intervention program, the Affect School, on stress, psychological symptoms, cognitive functioning and neural activity. Fifty employees in social service and education, with high levels of chronic stress, were randomly divided into a treatment (N= 27) and control (N= 23) group. Complete sets of data were available in 20 participants in the treatment group and 17 in the control group. The Perceived Stress Questionnaire assessed stress and the Symptom Check List-90 psychological symptoms before and after treatment. Episodic-memory functioning under focused and divided attention conditions was also assessed. Prior and after the Affect School, seven participants in the treatment group were studied with functional magnetic resonance imaging (fMRI) during episodic memory processing. After the Affect School there was a reduction in stress and psychological symptoms for the treatment group but not in the control group. The controls showed a reduction in episodic memory functioning whereas the performance of the treatment group remained intact. The fMRI scanning indicated a qualitative change in the neural network subserving episodic memory. These preliminary results suggest that the Affect School is effective on individuals with high stress.

  • 39. Bergdahl, Maud
    et al.
    Bergdahl, Jan
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Nilsson, Lars-Göran
    Psykologiska institutionen, Stockholms universitet.
    Difference in apolipoprotein E type 4 allele (APOE e4) amongdentate and edentulous subjects2008Ingår i: Gerodontology, ISSN 0734-0664, E-ISSN 1741-2358, Vol. 25, nr 3, s. 179-186Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives: To evaluate the frequency of apolipoprotein (APOE) alleles and determine whether APOE type 4 allele (e4) was associated with edentulousness even when certain factors were controlled.Background: The APOE are important in lipid homeostasis, and APOE e4 has been found in many diseases and to have a negative impact on longevity. Tooth loss is more common in ill aged subjects with low income and education.Materials and methods: In a population-based study involving 1860 subjects between 35 and 85 years 1321 dentate (mean age = 54; 54% women, 46% men) and 539 edentulous (mean age = 72; 62% women, 38% men) subjects were studied. Logistic regression was performed with dentate/edentulous as dependent variables and years of education, socio-economic status, social network, stress level, handicap from birth, 23 various diseases and APOE e4 as covariates. Thereafter, APOE e4 frequencies were studied in 342 dentateand 336 edentulous subjects 50–85 years of age. The subjects were matched with regard to age, gender, years of education, living condition, stress level, handicap from birth and 23 various diseases.Results: APOE allele frequency in the total group was e2 = 7.8%, e3 = 76.4% and e4 = 15.8%. Age, living condition, years of education and APOE e4 were significant covariates in edentulous subjects (p £ 0.001).APOE e4 in the matched groups revealed significant differences between the dentate group and the edentulous group (v2 = 5.68; p = 0.017). There was no group effect (F(29,648) = 0.849; p < 0.696; Wilks’ lambda = 0.963). In the dentate group, the frequencies of APOE were: e2 = 8.8%, e3 = 77.9% ande4 = 13.3%. Corresponding frequencies of APOE in the edentulous group were: e2 = 6.6%, e3 = 75.4% and e4 = 18.0%.Conclusion: Despite matching both groups with regard to different background factors, the edentulous group had a higher frequency of APOE e4 than the dentate group. Thus, genetic factors might contribute to greater risk in developing complex oral diseases leading to tooth loss or just be an indication that the subjects in our study carrying APOE e4 are more fragile.

  • 40. Bergdahl, Maud
    et al.
    Habib, Reza
    Bergdahl, Jan
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Nilsson, Lars-Göran
    Natural teeth and cognitive function in humans2007Ingår i: Scandinavian Journal of Psychology, ISSN 0036-5564, E-ISSN 1467-9450, Vol. 48, nr 6, s. 557-565Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A number of neurobiological, psychological and social factors may account for cognitive impairment. In animal studies a relation between dental status and cognitive performance has been found. It is unclear whether such a relation exists for humans. In a first step we compared the performance of 1,351 participants (53% women, 47% men; age M = 54.0) with natural teeth to 487 edentulous participants (59% women, 41% men; age M = 71.3) on 12 cognitive tests. The natural teeth group had a lower mean age, fewer women, more years of education, higher mini-mental state (MMSE), and performed significantly higher on several cognitive tests. In a subsequent analysis, the cognitive performance of a subset of the participants (50–85 years) was examined. In this analysis, 211 had natural dentition and 188 were edentulous. The groups were matched for gender, age, social variables, diseases, stress and MMSE. The cognitive disadvantage of the edentulous group was still apparent. The results suggest that functional natural teeth relate to relatively preserved cognitive functioning in older age.

  • 41.
    Berginström, Nils
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Geriatrik.
    Nordström, Peter
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Geriatrik.
    Ekman, Urban
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi. Karolinska Inst, Dept Neurobiol Care Sci & Soc, Stockholm, Sweden.
    Eriksson, Johan
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi.
    Andersson, Micael
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi.
    Nordström, Anna
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin. Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Geriatrik.
    Using Functional Magnetic Resonance Imaging to Detect Chronic Fatigue in Patients With Previous Traumatic Brain Injury: changes linked to altered Striato-Thalamic-Cortical Functioning2018Ingår i: The journal of head trauma rehabilitation, ISSN 0885-9701, E-ISSN 1550-509X, Vol. 33, nr 4, s. 266-274Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: To investigate whether functional magnetic resonance imaging (fMRI) can be used to detect fatigue after traumatic brain injury (TBI).

    Setting: Neurorehabilitation clinic.

    Participants: Patients with TBI (n = 57) and self-experienced fatigue more than 1 year postinjury, and age- and gender-matched healthy controls (n = 27).

    Main Measures: Self-assessment scales of fatigue, a neuropsychological test battery, and fMRI scanning during performance of a fatiguing 27-minute attention task.

    Results: During testing within the fMRI scanner, patients showed a higher increase in self-reported fatigue than controls from before to after completing the task (P < .001).The patients also showed lower activity in several regions, including bilateral caudate, thalamus, and anterior insula (all P < .05). Furthermore, the patients failed to display decreased activation over time in regions of interest: the bilateral caudate and anterior thalamus (all P < .01). Left caudate activity correctly identified 91% of patients and 81% of controls, resulting in a positive predictive value of 91%.

    Conclusion: The results suggest that chronic fatigue after TBI is associated with altered striato-thalamic-cortical functioning. It would be of interest to study whether fMRI can be used to support the diagnosis of chronic fatigue in future studies.

  • 42.
    Berginström, Nils
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Geriatrik.
    Nordström, Peter
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Geriatrik. School of Sport Sciences, The Arctic University of Norway, Tromsø, Norway Medicine.
    Ekman, Urban
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
    Eriksson, Johan
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Nordström, Anna
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för hållbar hälsa. School of Sport Sciences, The Arctic University of Norway, Tromsø, Norway.
    Pharmaco-fMRI in Patients With Traumatic Brain Injury: A Randomized Controlled Trial With the Monoaminergic Stabilizer (-)-OSU61622019Ingår i: The journal of head trauma rehabilitation, ISSN 0885-9701, E-ISSN 1550-509X, Vol. 34, nr 3, s. 189-198Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: To examine the effects of monoaminergic stabilizer (-)-OSU6162 on brain activity, as measured by blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI), in patients in the chronic phase of traumatic brain injury suffering from fatigue.

    SETTING: Neurorehabilitation clinic.

    PARTICIPANTS: Patients with traumatic brain injury received either placebo (n = 24) or active treatment (n = 28). Healthy controls (n = 27) went through fMRI examination at one point and were used in sensitivity analysis on normalization of BOLD response.

    DESIGN: Randomized, double-blinded, placebo-controlled design.

    MAIN MEASURES: Effects on BOLD signal changes from before to after treatment during performance of a fatiguing attention task.

    RESULTS: The fMRI results revealed treatment effects within the right occipitotemporal cortex and the right orbitofrontal cortex. In these regions, the BOLD response was normalized relative to healthy controls at the postintervention fMRI session. No effects were seen in regions in which we previously observed activity differences between patients and healthy controls while performing this fMRI task, such as the striatum.

    CONCLUSION: (-)-OSU6162 treatment had influences on functional brain activity, although the normalized regional BOLD response was observed in regions that were not a priori hypothesized to be sensitive to this particular treatment, and was not accompanied by any effects on in-scanner test performance or on fatigue.

  • 43.
    Berginström, Nils
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Geriatrik. Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Nordström, Peter
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Geriatrik.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Nordström, Anna
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för hållbar hälsa. School of Sport Sciences, The Arctic University of Norway, Tromsø, Norway..
    White matter hyperintensities increases with traumatic brain injury severity: associations to neuropsychological performance and fatigue2020Ingår i: Brain Injury, ISSN 0269-9052, E-ISSN 1362-301X, Vol. 34, nr 3, s. 415-420Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: To examine the prevalence of white matter hyperintensities (WMHs) in patients with traumatic brain injury (TBI) as compared to healthy controls, and to investigate whether there is an association between WMH lesion burden and performance on neuropsychological tests in patients with TBI.

    Methods: A total of 59 patients with TBI and 27 age- and gender-matched healthy controls underwent thorough neuropsychological testing and magnetic resonance imaging. The quantification of WMH lesions was performed using the fully automated Lesion Segmentation Tool.

    Results: WMH lesions were more common in patients with TBI than in healthy controls (p = .032), and increased with higher TBI severity (p = .025). Linear regressions showed that WMH lesions in patients with TBI were not related to performance on any neuropsychological tests (p > .05 for all). However, a negative relationship between number of WMH lesions in patients with TBI and self-assessed fatigue was found (r = - 0.33, p = .026).

    Conclusion: WMH lesions are more common in patients with TBI than in healthy controls, and WMH lesions burden increases with TBI severity. These lesions could not explain decreased cognitive functioning in patients with TBI but did relate to decreased self-assessment of fatigue after TBI.

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  • 44.
    Berglin, Eva
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Reumatologi.
    Lorentzon, Ronnie
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Idrottsmedicin.
    Nordmark, L
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Nilsson-Sojka, Birgitta
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Klinisk immunologi.
    Rantapää Dahlqvist, Solbritt
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Reumatologi.
    Predictors of radiological progression and changes in hand bone density in early rheumatoid arthritis2003Ingår i: Rheumatology, ISSN 1462-0324, E-ISSN 1462-0332, Vol. 42, nr 2, s. 268-275Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: To identify predictors for radiological and functional outcome and bone loss in the hands in early rheumatoid arthritis (RA) during the first 2 yr of disease and to study the relationship between these variables.

    METHODS: An inception cohort of consecutively recruited patients was examined at baseline and after 12 and 24 months using X-rays of hands and feet, clinical [28-joint count, Health Assessment Questionnaire (HAQ), global visual analogue scale (VAS), grip strength] and laboratory (erythrocyte sedimentation rate, C-reactive protein, markers of bone formation and resorption) measurements and dual-energy X-ray absorptiometry measurements of the hands.

    RESULTS: Joint destruction increased significantly during the study, with the Larsen score at baseline as the strongest predictor. Radiological progression and bone loss over 24 months were significantly retarded in patients responding to therapy. The effects of the shared epitope and initial high inflammatory activity on radiological progression were overridden by the therapeutic response. Radiological progression correlated significantly with bone loss. Global VAS, Larsen score and HAQ at inclusion significantly predicted change in HAQ over time.

    CONCLUSIONS: Radiological progression and bone loss were retarded by early therapeutic response. Bone loss was related to radiological progression.

  • 45. Berglund, Johan
    et al.
    Skorpil, Mikael
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Multi-scale graph-cut algorithm for efficient water-fat separation2017Ingår i: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 78, nr 3, s. 941-949Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To improve the accuracy and robustness to noise in water-fat separation by unifying the multiscale and graph cut based approaches to B0 -correction.

    METHODS: A previously proposed water-fat separation algorithm that corrects for B0 field inhomogeneity in 3D by a single quadratic pseudo-Boolean optimization (QPBO) graph cut was incorporated into a multi-scale framework, where field map solutions are propagated from coarse to fine scales for voxels that are not resolved by the graph cut. The accuracy of the single-scale and multi-scale QPBO algorithms was evaluated against benchmark reference datasets. The robustness to noise was evaluated by adding noise to the input data prior to water-fat separation.

    RESULTS: Both algorithms achieved the highest accuracy when compared with seven previously published methods, while computation times were acceptable for implementation in clinical routine. The multi-scale algorithm was more robust to noise than the single-scale algorithm, while causing only a small increase (+10%) of the reconstruction time.

    CONCLUSION: The proposed 3D multi-scale QPBO algorithm offers accurate water-fat separation, robustness to noise, and fast reconstruction. The software implementation is freely available to the research community. Magn Reson Med, 2016. © 2016 International Society for Magnetic Resonance in Medicine.

  • 46.
    Bergman, Frida
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Allmänmedicin.
    Matsson-Frost, Tove
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Allmänmedicin.
    Jonasson, Lars S.
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Chorell, Elin
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för medicin.
    Sörlin, Ann
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering.
    Wennberg, Patrik
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Allmänmedicin.
    Öhberg, Fredrik
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Ryberg, Mats
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för medicin.
    Levine, James A
    Mayo Clinic Rochester MN, USA; Fondation IPSEN, Paris, France.
    Olsson, Tommy
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för medicin.
    Boraxbekk, Carl-Johan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Danish Research Center for Magnetic Resonance (DRCMR), Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital, Hvidovre, Denmark; Institute of Sports Medicine Copenhagen (ISMC), Copenhagen University Hospital, Copenhagen, Denmark.
    Walking Time Is associated With Hippocampal Volume in Overweight and Obese Office Workers2020Ingår i: Frontiers in Human Neuroscience, E-ISSN 1662-5161, Vol. 14, artikel-id 307Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives: To investigate the long-term effects on cognition and brain function after installing treadmill workstations in offices for 13 months.

    Methods: Eighty healthy overweight or obese office workers aged 40–67 years were individually randomized to an intervention group, receiving a treadmill workstation and encouraging emails, or to a control group, continuing to work as usual. Effects on cognitive function, hippocampal volume, prefrontal cortex (PFC) thickness, and circulating brain-derived neurotrophic factor (BDNF) were analyzed. Further, mediation analyses between changes in walking time and light-intensity physical activity (LPA) on changes in BDNF and hippocampal volume between baseline and 13 months, and multivariate analyses of the baseline data with percentage sitting time as the response variable, were performed.

    Results: No group by time interactions were observed for any of the outcomes. In the mediation analyses, positive associations between changes in walking time and LPA on changes in hippocampal volume were observed, although not mediated by changes in BDNF levels. In the multivariate analyses, a negative association between percentage sitting time and hippocampal volume was observed, however only among those older than 51 years of age.

    Conclusion: Although no group by time interactions were observed, our analyses suggest that increased walking and LPA may have positive effects on hippocampal volume and that sedentary behavior is associated with brain structures of importance for memory functions.

    Trial Registration: www.ClinicalTrials.gov as NCT01997970.

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  • 47.
    Bergouignan, Loretxu
    et al.
    BCBL, Basque Center on Cognition, Brain and Language, Donostia, Spain.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Ehrsson, H. Henrik
    Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Out-of-body memory encoding causes third-person perspective at recall2022Ingår i: Journal of Cognitive Psychology, ISSN 2044-5911, E-ISSN 2044-592X, Vol. 34, nr 1, s. 160-178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sigmund Freud famously noted some memories are recalled with a perspective of “an observer from outside the scene”. According to Freud—and most memory researchers today—the third-person perspective occurs due to reconstructive processes at recall. An alternative possibility is that the third-person perspective have been adopted when the actual event is experienced and later recalled in its original form. Here we test this hypothesis using a perceptual out-of-body illusion during the encoding of real events. Participants took part in a social interaction while experiencing an out-of-body illusion where they viewed the event and their own body from a third-person perspective. In recall sessions ∼1 week later, events encoded in the out-of-body compared to the in-body control condition were significantly less recalled from a first-person perspective. An out-of-body experience leads to more third-person perspective during recollection.

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  • 48. Bergouignan, Loretxu
    et al.
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Ehrsson, H. Henrik
    Out-of-body-induced hippocampal amnesia2014Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 111, nr 12, s. 4421-4426Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Theoretical models have suggested an association between the ongoing experience of the world from the perspective of one's own body and hippocampus-based episodic memory. This link has been supported by clinical reports of long-term episodic memory impairments in psychiatric conditions with dissociative symptoms, in which individuals feel detached from themselves as if having an out-of-body experience. Here, we introduce an experimental approach to examine the necessary role of perceiving the world from the perspective of one's own body for the successful episodic encoding of real-life events. While participants were involved in a social interaction, an out-of-body illusion was elicited, in which the sense of bodily self was displaced from the real body to the other end of the testing room. This condition was compared with a well-matched in-body illusion condition, in which the sense of bodily self was colocalized with the real body. In separate recall sessions, performed similar to 1 wk later, we assessed the participants' episodic memory of these events. The results revealed an episodic recollection deficit for events encoded out-of-body compared with in-body. Functional magnetic resonance imaging indicated that this impairment was specifically associated with activity changes in the posterior hippocampus. Collectively, these findings show that efficient hippocampus-based episodic-memory encoding requires a first-person perspective of the natural spatial relationship between the body and the world. Our observations have important implications for theoretical models of episodic memory, neurocognitive models of self, embodied cognition, and clinical research into memory deficits in psychiatric disorders.

  • 49.
    Bitar, Robert
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    The prevalence and clinical features of SWEDD in the NYPUM study -a retrospective analysis2016Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 50.
    Björeland, Ulrika
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Nyholm, Tufve
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Jonsson, Joakim
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Skorpil, Mikael
    Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
    Blomqvist, Lennart
    Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
    Strandberg, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Beckman, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Thellenberg-Karlsson, Camilla
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Onkologi.
    Impact of neoadjuvant androgen deprivation therapy on magnetic resonance imaging features in prostate cancer before radiotherapy2021Ingår i: Physics and Imaging in Radiation Oncology, E-ISSN 2405-6316, Vol. 17, s. 117-123Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background and purpose: In locally advanced prostate cancer (PC), androgen deprivation therapy (ADT) in combination with whole prostate radiotherapy (RT) is the standard treatment. ADT affects the prostate as well as the tumour on multiparametric magnetic resonance imaging (MRI) with decreased PC conspicuity and impaired localisation of the prostate lesion. Image texture analysis has been suggested to be of aid in separating tumour from normal tissue. The aim of the study was to investigate the impact of ADT on baseline defined MRI features in prostate cancer with the goal to investigate if it might be of use in radiotherapy planning.

    Materials and methods: Fifty PC patients were included. Multiparametric MRI was performed before, and three months after ADT. At baseline, a tumour volume was delineated on apparent diffusion coefficient (ADC) maps with suspected tumour content and a reference volume in normal prostatic tissue. These volumes were transferred to MRIs after ADT and were analysed with first-order -and invariant Haralick -features.

    Results: At baseline, the median value and several of the invariant Haralick features of ADC, showed a significant difference between tumour and reference volumes. After ADT, only ADC median value could significantly differentiate the two volumes.

    Conclusions: Invariant Haralick -features could not distinguish between baseline MRI defined PC and normal tissue after ADT. First-order median value remained significantly different in tumour and reference volumes after ADT, but the difference was less pronounced than before ADT.

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