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  • 1. Ahlén Bergman, Emma
    et al.
    Hartana, Ciputra Adijaya
    Johansson, Markus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Urology and Andrology. Department of Urology, Sundsvall Hospital, Sundsvall, Sweden..
    Linton, Ludvig B
    Berglund, Sofia
    Hyllienmark, Martin
    Lundgren, Christian
    Holmström, Benny
    Palmqvist, Karin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Urology and Andrology. Department of Surgery, Urology Section, Östersund County Hospital, Östersund, Sweden.
    Hansson, Johan
    Alamdari, Farhood
    Huge, Ylva
    Aljabery, Firas
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Winerdal, Malin E
    Krantz, David
    Zirakzadeh, A. Ali
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Urology and Andrology. Unit of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
    Marits, Per
    Sjöholm, Louise K
    Sherif, Amir
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Urology and Andrology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Winqvist, Ola
    Increased CD4+ T cell lineage commitment determined by CpG methylation correlates with better prognosis in urinary bladder cancer patients2018In: Clinical Epigenetics, E-ISSN 1868-7083, Vol. 10, article id 102Article in journal (Refereed)
    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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  • 2.
    Andersson, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Granberg, Christoffer
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    A novel system for quality assurance of radiology equipment2018In: EuroSafe Imaging 2018 / ESI-0064, EuroSafe Imaging , 2018Conference paper (Refereed)
  • 3.
    Andersson, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Karpe, Fredrik
    NIHR Oxford Biomedical Research Centre, Churchill Hospital, Oxford, UK.
    Sjöström, Lars-Göran
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Söderberg, Stefan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Olsson, Tommy
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Association of adipose tissue blood flow with fat depot sizes and adipokines in women2012In: International Journal of Obesity, ISSN 0307-0565, E-ISSN 1476-5497, Vol. 36, no 6, p. 783-789Article in journal (Refereed)
    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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  • 4.
    Andersson, Ronny
    et al.
    Umeå University, Faculty of Medicine, Radiation Sciences, Oncology.
    Hofer, Åke
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Dermatology and Venerology.
    Riklund-Åhlström, Katrine
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Henriksson, Roger
    Umeå University, Faculty of Medicine, Radiation Sciences, Oncology.
    Effects of interferon-[alpha], verapamil and dacarbazine in the treatment of advanced malignant melanoma2003In: Melanoma research, ISSN 0960-8931, E-ISSN 1473-5636, Vol. 13, no 1, p. 87-91Article in journal (Refereed)
    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.

  • 5. Arheden, Håkan
    et al.
    Aspelin, Peter
    Bajc, Marika
    Damm, Sabine
    Flodmark, Olof
    Friberg, Peter
    Gustafsson, Lars
    Holtås, Stig
    Modin, Agnes
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Rydh, Anders
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Functional imaging medicine: a new specialty with great prospects2006In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 103, no 39, p. 2883-2884Article in journal (Refereed)
  • 6.
    Asklund, Thomas
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Henriksson, Roger
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Bergström, Åsa
    Kasper, Maria
    Ögren, Margareta
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Toftgård, Rune
    Riklund, Katrine Åhlström
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Early and persisting response to vismodegib in a patient with bone metastasizing medulloblastoma2013In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 52, no 4, p. 862-865Article in journal (Refereed)
  • 7.
    Asklund, Thomas
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Sandström, Maria
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Shahidi, Saeed
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Henriksson, Roger
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Durable stabilization of three chordoma cases by bevacizumab and erlotinib2014In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 53, no 7, p. 980-984Article in journal (Refereed)
  • 8. 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 University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    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, Germany2018In: Molecular Imaging and Biology, ISSN 1536-1632, E-ISSN 1860-2002, Vol. 20, no 1, p. 4-20Article, review/survey (Refereed)
    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.

  • 9. 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 University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    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, Germany2016In: Molecular Imaging and Biology, ISSN 1536-1632, E-ISSN 1860-2002, Vol. 18, no 5, p. 637-650Article in journal (Refereed)
    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.

  • 10.
    Bergdahl, Jan
    et al.
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Nilsson, Lars-Göran
    Riklund Åhlström, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Nyberg, Lars
    Umeå University, Faculty of Social Sciences, Department of Psychology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Treatment of chronic stress in employees: subjective, cognitive and neural correlates2005In: Scandinavian Journal of Psychology, ISSN 0036-5564, E-ISSN 1467-9450, Vol. 46, no 5, p. 395-402Article in journal (Refereed)
    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.

  • 11.
    Björeland, Ulrika
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Nyholm, Tufve
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Jonsson, Joakim
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    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 University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Beckman, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Thellenberg-Karlsson, Camilla
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Impact of neoadjuvant androgen deprivation therapy on magnetic resonance imaging features in prostate cancer before radiotherapy2021In: Physics and Imaging in Radiation Oncology, E-ISSN 2405-6316, Vol. 17, p. 117-123Article in journal (Refereed)
    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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  • 12.
    Björeland, Ulrika
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Strandberg, Sara
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Söderkvist, Karin
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Nyholm, Tufve
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Jonsson, Joakim
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Skorpil, Mikael
    Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
    Blomqvist, Lennart
    Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Beckman, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Thellenberg-Karlsson, Camilla
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Diffusion-weighted MRI and 11C-acetate-PET/CT imaging in high-risk/very high-risk prostate cancerManuscript (preprint) (Other academic)
  • 13. Brolin, Gustav
    et al.
    Edenbrandt, Lars
    Granerus, Goeran
    Olsson, Anna
    Afzelius, David
    Gustafsson, Agneta
    Jonsson, Cathrine
    Hagerman, Jessica
    Johansson, Lena
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. EQUALIS AB, Uppsala, Sweden.
    Ljungberg, Michael
    The accuracy of quantitative parameters in Tc-99m-MAG3 dynamic renography: a national audit based on virtual image data2016In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 36, no 2, p. 146-154Article in journal (Refereed)
    Abstract [en]

    Assessment of image analysis methods and computer software used in Tc-99m-MAG3 dynamic renography is important to ensure reliable study results and ultimately the best possible care for patients. In this work, we present a national multicentre study of the quantification accuracy in Tc-99m-MAG3 renography, utilizing virtual dynamic scintigraphic data obtained by Monte Carlo-simulated scintillation camera imaging of digital phantoms with time-varying activity distributions. Three digital phantom studies were distributed to the participating departments, and quantitative evaluation was performed with standard clinical software according to local routines. The differential renal function (DRF) and time to maximum renal activity (T-max) were reported by 21 of the 28 Swedish departments performing Tc-99m-MAG3 studies as of 2012. The reported DRF estimates showed a significantly lower precision for the phantom with impaired renal uptake than for the phantom with normal uptake. The T-max estimates showed a similar trend, but the difference was only significant for the right kidney. There was a significant bias in the measured DRF for all phantoms caused by different positions of the left and right kidney in the anterior-posterior direction. In conclusion, this study shows that virtual scintigraphic studies are applicable for quality assurance and that there is a considerable uncertainty associated with standard quantitative parameters in dynamic Tc-99m-MAG3 renography, especially for patients with impaired renal function.

  • 14.
    Bäckström, David C
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences. DeDepartment of Neurology, Yale University, New Haven, CT, USA.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Trupp, Miles
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Zetterberg, Henrik
    Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Neurodegenerative Disease and UCL Queen Square Institute of Neurology, London, UK; UK Dementia Research Institute at UCL, London, UK.
    Blennow, Kaj
    Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Eriksson Domellöf, Magdalena
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Prediction and early biomarkers of cognitive decline in Parkinson disease and atypical parkinsonism: a population-based study2022In: Brain Communications, E-ISSN 2632-1297, Vol. 4, no 2Article in journal (Refereed)
    Abstract [en]

    The progression of cognitive decline is heterogeneous in the three most common idiopathic parkinsonian diseases: Parkinson disease, multiple system atrophy and progressive supranuclear palsy. The causes for this heterogeneity are not fully understood, and there are no validated biomarkers that can accurately identify patients who will develop dementia and when. In this population-based, prospective study, comprehensive neuropsychological testing was performed repeatedly in new-onset, idiopathic parkinsonism. Dementia was diagnosed until 10 years and participants (N = 210) were deeply phenotyped by multimodal clinical, biochemical, genetic and brain imaging measures. At baseline, before the start of dopaminergic treatment, mild cognitive impairment was prevalent in 43.4% of the patients with Parkinson disease, 23.1% of the patients with multiple system atrophy and 77.8% of the patients with progressive supranuclear palsy. Longitudinally, all three diseases had a higher incidence of cognitive decline compared with healthy controls, but the types and severity of cognitive dysfunctions differed. In Parkinson disease, psychomotor speed and attention showed signs of improvement after dopaminergic treatment, while no such improvement was seen in other diseases. The 10-year cumulative probability of dementia was 54% in Parkinson disease and 71% in progressive supranuclear palsy, while there were no cases of dementia in multiple system atrophy. An easy-to-use, multivariable model that predicts the risk of dementia in Parkinson disease within 10 years with high accuracy (area under the curve: 0.86, P < 0.001) was developed. The optimized model adds CSF biomarkers to four easily measurable clinical features at baseline (mild cognitive impairment, olfactory function, motor disease severity and age). The model demonstrates a highly variable but predictable risk of dementia in Parkinson disease, e.g. a 9% risk within 10 years in a patient with normal cognition and CSF amyloid-β42 in the highest tertile, compared with an 85% risk in a patient with mild cognitive impairment and CSF amyloid-β42 in the lowest tertile. Only small or no associations with cognitive decline were found for factors that could be easily modifiable (such as thyroid dysfunction). Risk factors for cognitive decline in multiple system atrophy and progressive supranuclear palsy included signs of systemic inflammation and eye movement abnormalities. The predictive model has high accuracy in Parkinson disease and might be used for the selection of patients into clinical trials or as an aid to improve the prevention of dementia. 

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  • 15.
    Bäckström, David C
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Lenfeldt, Niklas
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Neurofilament concentration in CSF correlates with disease severity, survival and imaging measures of neurodegeneration in incident Parkinson diseaseManuscript (preprint) (Other academic)
  • 16.
    Bäckström, David C
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    Lenfeldt, Niklas
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Neurosciences.
    NfL as a biomarker for neurodegeneration and survival in Parkinson disease2020In: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 95, no 7, p. e827-e838Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To determine whether neurofilament light chain protein in CSF (cNfL), a sensitive biomarker of neuroaxonal damage, reflects disease severity or can predict survival in Parkinson disease (PD).

    METHODS: We investigated whether disease severity, phenotype, or survival in patients with new-onset PD correlates with cNfL concentrations around the time of diagnosis in the population-based New Parkinsonism in Umeå (NYPUM) study cohort (n = 99). A second, larger new-onset PD cohort (n = 194) was used for independent validation. Association of brain pathology with the cNfL concentration was examined with striatal dopamine transporter imaging and repeated diffusion tensor imaging at baseline and 1 and 3 years.

    RESULTS: Higher cNfL in the early phase of PD was associated with greater severity of all cardinal motor symptoms except tremor in both cohorts and with shorter survival and impaired olfaction. cNfL concentrations above the median of 903 ng/L conferred an overall 5.8 times increased hazard of death during follow-up. After adjustment for age and sex, higher cNfL correlated with striatal dopamine transporter uptake deficits and lower fractional anisotropy in diffusion tensor imaging of several axonal tracts.

    CONCLUSIONS: cNfL shows usefulness as a biomarker of disease severity and to predict survival in PD. The present results indicate that the cNfL concentration reflects the intensity of the neurodegenerative process, which could be important in future clinical trials.

    CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with PD, cNfL concentrations are associated with more severe disease and shorter survival.

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  • 17.
    Bäckström, David
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Eriksson Domellöf, Magdalenax
    Umeå University, Faculty of Social Sciences, Department of Psychology. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Linder, Jan
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Early predictors of mortality in parkinsonism and Parkinson disease: A population-based study2018In: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 91, no 22, p. E2045-E2056Article in journal (Refereed)
    Abstract [en]

    Objective To examine mortality and associated risk factors, including possible effects of mild cognitive impairment, imaging, and CSF abnormalities, in a community-based population with incident parkinsonism and Parkinson disease. Methods One hundred eighty-two patients with new-onset, idiopathic parkinsonism were diagnosed from January 2004 through April 2009, in a catchment area of 142,000 inhabitants in Sweden. Patients were comprehensively investigated according to a multimodal research protocol and followed prospectively for up to 13.5 years. A total of 109 patients died. Mortality rates in the general Swedish population were used to calculate standardized mortality ratio and expected survival, and Cox proportional hazard models were used to investigate independent predictors of mortality. Results The standardized mortality ratio for all patients was 1.84 (95% confidence interval 1.50-2.22, p < 0.001). Patients with atypical parkinsonism (multiple system atrophy or progressive supranuclear palsy) had the highest mortality. In early Parkinson disease, a mild cognitive impairment diagnosis, freezing of gait, hyposmia, reduced dopamine transporter activity in the caudate, and elevated leukocytes in the CSF were significantly associated with shorter survival. Conclusion Although patients presenting with idiopathic parkinsonism have reduced survival, the survival is highly dependent on the type and characteristics of the parkinsonian disorder. Patients with Parkinson disease presenting with normal cognitive function seem to have a largely normal life expectancy. The finding of a subtle CSF leukocytosis in patients with Parkinson disease with short survival may have clinical implications.

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  • 18. de Boer, Lieke
    et al.
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Chowdhury, Rumana
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Dolan, Raymond J.
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology.
    Backman, Lars
    Guitart-Masip, Marc
    Dorsal striatal dopamine D1 receptor availability predicts an instrumental bias in action learning2019In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, no 1, p. 261-270Article in journal (Refereed)
    Abstract [en]

    Learning to act to obtain reward and inhibit to avoid punishment is easier compared with learning the opposite contingencies. This coupling of action and valence is often thought of as a Pavlovian bias, although recent research has shown it may also emerge through instrumental mechanisms. We measured this learning bias with a rewarded go/no-go task in 60 adults of different ages. Using computational modeling, we characterized the bias as being instrumental. To assess the role of endogenous dopamine (DA) in the expression of this bias, we quantified DA D1 receptor availability using positron emission tomography (PET) with the radioligand [11C]SCH23390. Using principal-component analysis on the binding potentials in a number of cortical and striatal regions of interest, we demonstrated that cortical, dorsal striatal, and ventral striatal areas provide independent sources of variance in DA D1 receptor availability. Interindividual variation in the dorsal striatal component was related to the strength of the instrumental bias during learning. These data suggest at least three anatomical sources of variance in DA D1 receptor availability separable using PET in humans, and we provide evidence that human dorsal striatal DA D1 receptors are involved in the modulation of instrumental learning biases.

  • 19. de Boer, Lieke
    et al.
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Dayan, Peter
    Backman, Lars
    Guitart-Masip, Marc
    Attenuation of dopamine-modulated prefrontal value signals underlies probabilistic reward learning deficits in old age2017In: eLIFE, E-ISSN 2050-084X, Vol. 6, article id e2642Article in journal (Refereed)
    Abstract [en]

    Probabilistic reward learning is characterised by individual differences that become acute in aging. This may be due to age-related dopamine (DA) decline affecting neural processing in striatum, prefrontal cortex, or both. We examined this by administering a probabilistic reward learning task to younger and older adults, and combining computational modelling of behaviour, fMRI and PET measurements of DA D1 availability. We found that anticipatory value signals in ventromedial prefrontal cortex (vmPFC) were attenuated in older adults. The strength of this signal predicted performance beyond age and was modulated by D1 availability in nucleus accumbens. These results uncover that a value-anticipation mechanism in vmPFC declines in aging, and that this mechanism is associated with DA D1 receptor availability.

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  • 20. de Boer, Lieke
    et al.
    Garzón, Benjamín
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Department of Radiation Sciences, Diagnostic Radiology, University Hospital, Umeå University, Umeå, Sweden.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Department of Radiation Sciences, Diagnostic Radiology, University Hospital, Umeå University, Umeå, Sweden.
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Department of Radiation Sciences, Diagnostic Radiology, University Hospital, Umeå University, Umeå, Sweden.
    Bäckman, Lars
    Guitart-Masip, Marc
    Corticostriatal White Matter Integrity and Dopamine D1 Receptor Availability Predict Age Differences in Prefrontal Value Signaling during Reward Learning2020In: Cerebral Cortex, ISSN 1047-3211, E-ISSN 1460-2199, Vol. 30, no 10, p. 5270-5280Article in journal (Refereed)
    Abstract [en]

    Probabilistic reward learning reflects the ability to adapt choices based on probabilistic feedback. The dopaminergically innervated corticostriatal circuit in the brain plays an important role in supporting successful probabilistic reward learning. Several components of the corticostriatal circuit deteriorate with age, as it does probabilistic reward learning. We showed previously that D1 receptor availability in NAcc predicts the strength of anticipatory value signaling in vmPFC, a neural correlate of probabilistic learning that is attenuated in older participants and predicts probabilistic reward learning performance. We investigated how white matter integrity in the pathway between nucleus accumbens (NAcc) and ventromedial prefrontal cortex (vmPFC) relates to the strength of anticipatory value signaling in vmPFC in younger and older participants. We found that in a sample of 22 old and 23 young participants, fractional anisotropy in the pathway between NAcc and vmPFC predicted the strength of value signaling in vmPFC independently from D1 receptor availability in NAcc. These findings provide tentative evidence that integrity in the dopaminergic and white matter pathways of corticostriatal circuitry supports the expression of value signaling in vmPFC which supports reward learning, however, the limited sample size calls for independent replication. These and future findings could add to the improved understanding of how corticostriatal integrity contributes to reward learning ability.

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  • 21.
    Ekman, Urban
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Eriksson, Johan
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Forsgren, Lars
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Jakobson Mo, Susanna
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Functional brain activity and presynaptic dopamine uptake in patients with Parkinson's disease and mild cognitive impairment: a cross-sectional study2012In: Lancet Neurology, ISSN 1474-4422, E-ISSN 1474-4465, Vol. 11, no 8, p. 679-687Article in journal (Refereed)
    Abstract [en]

    Background: Many patients with Parkinson's disease have mild cognitive impairment (MCI). Deficits in executive functions and working memory suggest dysfunctional frontostriatal brain circuitry. We aimed to assess brain responses during a working memory task in a cohort of newly diagnosed drug-naive patients with Parkinson's disease with and without MCI.

    Methods: Participants were recruited within a prospective cohort study of incident patients with idiopathic parkinsonism, including Parkinson's disease. Between Jan 1, 2004, and April 30, 2009, all physicians in the Umea catchment area were requested to refer all individuals with suspected parkinsonism to the Department of Neurology at lima University. Included patients fulfilled the UK Parkinson's Disease Society Brain Bank clinical diagnostic criteria for Parkinson's disease. Control individuals were matched on the basis of age and sex with the first 50 patients included in the study. Participants who scored 1.5 SDs or more below the population mean on at least two cognitive measures were diagnosed with MCI. The primary outcome measures were functional MRI blood-oxygen-level-dependent signal and SPECT presynaptic uptake. Functional MRI was done during a verbal two-back working memory task. Presynaptic dopamine SPECT was done to assess presynaptic striatal dopaminergic system integrity. Event-related transient analyses of functional MRI data were done for the whole brain and for frontostriatal regions of interest, and semi-quantitative SPECT analyses were done for striatal regions of interest.

    Findings: Compared with controls (n=24), patients with Parkinson's disease (n=77) had under-recruitment in an extensive brain network including bilateral striatal and frontal regions (p<0.001). Within the Parkinson's disease group, patients with Parkinson's disease and MCI (n=30) had additional under-recruitment in the right dorsal caudate nucleus (p=0.005) and the bilateral anterior cingulate cortex (p<0.001) compared with patients with Parkinson's disease without MCI (n=26). In patients with Parkinson's disease and MCI, SPECT uptake in the right caudate was lower than in patients with Parkinson's disease without MCI (p=0.008) and correlated with striatal functional MRI blood-oxygen-level-dependent signal (r=0.32, p=0.031).

    Interpretation: These altered brain responses in patients with Parkinson's disease and MCI suggest that cognitive impairment is linked to frontostriatal dysfunction.

  • 22.
    Elgh, Eva
    et al.
    Umeå University, Faculty of Medicine, Community Medicine and Rehabilitation, Geriatric Medicine.
    Sundström, Torbjörn
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Näsman, Birgitta
    Umeå University, Faculty of Medicine, Community Medicine and Rehabilitation, Geriatric Medicine.
    Riklund Åhlström, Katrine
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Nyberg, Lars
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Memory functions and rCBF (99m)Tc-HMPAO SPET: developing diagnostics in Alzheimer's disease2002In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, ISSN 1619-7070, Vol. 29, no 9, p. 1140-1148Article in journal (Refereed)
    Abstract [en]

    Alzheimer's disease (AD) is a primary degenerative disease of the brain. The prevalence increases with age, with devastating consequences for the individual and society. The aim of this study was to evaluate whether patients with early AD show an altered regional cerebral blood flow (rCBF) compared with control persons. Furthermore, we aimed to investigate the correlation between rCBF in sublobar volumes of the brain and performance on memory tests. Memory tests were chosen to evaluate episodic and semantic memory. Fourteen patients (aged 75.2+/-8.8 years) with early AD and 15 control persons (aged 71.4+/-3.2 years) were included. rCBF measurements with single-photon emission tomography (SPET) using technetium-99m hexamethylpropylene amine oxime (HMPAO) were performed. The rCBF (99m)Tc-HMPAO SPET images were spatially transformed to fit a brain atlas and normalised for differences in rCBF (Computerised Brain Atlas software). Cortical and subcortical volumes of interest (VOIs) were analysed and compared. Compared with the controls, AD patients showed a significantly lower rCBF ratio in temporoparietal regions, including the left hippocampus. The diagnostic sensitivity and specificity for AD were high in temporoparietal regions. AD patients had significantly reduced performance on semantic and, in particular, episodic memory tests compared with age-matched normative data, and their performance on several episodic tests correlated with rCBF ratios in parietal and temporal regions, including the left hippocampus. The correlation between rCBF ratio and level of episodic memory performance suggests that abnormalities in rCBF pattern underlie impaired episodic memory functioning in AD.

  • 23.
    Eriksson, David
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Blomberg, Jeanette
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Lindgren, Theres
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Löfroth, Per-Olov
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Johansson, Lennart
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Stigbrand, Torgny
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Iodine-131 induces mitotic catastrophes and activates apoptotic pathways in HeLa Hep2 cells2008In: Cancer Biotherapy and Radiopharmaceuticals, ISSN 1084-9785, E-ISSN 1557-8852, Vol. 23, no 5, p. 541-549Article in journal (Refereed)
    Abstract [en]

    Iodine-131 (131I) has been used both in unconjugated form and conjugated to antibody derivates (i.e., radioimmunotherapy; RIT) to treat malignant diseases. The mechanisms by which 131I-irradiation causes growth retardation are, however, inadequately understood. The aim of this study was to elucidate the sequential molecular and cellular events that initiate cell death in HeLa Hep2 cells exposed to 131I. In this paper, HeLa Hep2 cells were found to display a transient G2-M arrest following irradiation, but then reentered the cell cycle still containing unrepaired cellular damage. An increase of multipolar mitotic spindles, as well as a significant increase in centrosome numbers from 8.8% +/- 1.9% in controls to 54.7% +/- 2.2% in irradiated cells, was observed (p < 0.0001). A subsequent failure of cytokinesis caused the cells to progress into mitotic catastrophe. This was accompanied by the formation of giant cells with multiple nuclei, multilobulated nuclei, and an increased frequency of polyploidy cells. A fraction of the cells also displayed apoptotic features, including the activation of initiator caspases-2, -8, -9, and effector caspase-3, as well as cleavage of poly(ADP-ribose) polymerase, a cell-death substrate for active caspase-3. These findings demonstrate that mitotic catastrophes and the activation of a delayed type of apoptosis might be important mechanisms involved in cell death following the RIT of solid tumors with -emitting radionuclides, such as 131I.

  • 24.
    Eriksson, David
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Löfroth, Per-Olov
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Johansson, Lennart
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Stigbrand, Torgny
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Apoptotic signalling in HeLa Hep2 cells following 5 Gy of cobalt-60 gamma radiation2009In: Anticancer Research, ISSN 0250-7005, E-ISSN 1791-7530, Vol. 29, no 11, p. 4361-4366Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The apoptotic signalling pathways involved in the delayed type of apoptosis occurring in HeLa Hep2 cells following radiation were investigated. MATERIALS AND METHODS: HeLa Hep2 cells were exposed to 5 Gy of cobalt-60 radiation. The activation of caspase-2, caspase-8, caspase-9 and effector caspase-3 was investigated by caspase assay plates and Western blots. Cleavage of poly (ADP-ribose) polymerase (PARP) was analysed on Western blots. HeLa Hep2 cells were irradiated with or without preincubation with inhibitors of protein synthesis (cycloheximide, CHX) and caspases, followed by TUNEL staining and caspase assay plate evaluation. RESULTS: Initiator caspases-2, -8, -9, and effector caspase-3, were found to be activated and PARP cleaved following irradiation. CHX completely inhibited the caspase activation and the associated apoptosis. Pretreatment with caspase-2 inhibitor indicated that caspase-2 was involved in the execution of the apoptosis. CONCLUSION: Activation of the apoptotic signalling pathways following irradiation of HeLa Hep2 cells includes components from the intrinsic as well as the extrinsic pathways and seems to require de novo protein synthesis.

  • 25.
    Eriksson, David
    et al.
    Umeå University, Faculty of Medicine, Clinical Microbiology, Immunology/Immunchemistry.
    Löfroth, Per-Olov
    Umeå University, Faculty of Medicine, Radiation Sciences, Radiation Physics.
    Johansson, Lennart
    Umeå University, Faculty of Medicine, Radiation Sciences, Radiation Physics.
    Åhlström Riklund, Katrine
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Stigbrand, Torgny
    Umeå University, Faculty of Medicine, Clinical Microbiology, Immunology/Immunchemistry.
    Cell cycle disturbances and mitotic catastrophes in HeLa Hep2 cells following 2.5 to 10 Gy of ionizing radiation.2007In: Clin Cancer Res, ISSN 1078-0432, Vol. 13, no 18 Pt 2, p. 5501s-5508sArticle in journal (Refereed)
    Abstract [en]

    PURPOSE: Experimental radioimmunotherapy delivering absorbed doses of 2.5 to 10 Gy has been shown to cause growth retardation of tumors. The purpose of this study was to elucidate the sequential molecular and cellular events occurring in HeLa Hep2 cells exposed to such doses. METHODS: Dose-response curves, activation of cell cycle checkpoints, and mitotic behavior were investigated in HeLa Hep2 cells following 2.5- to 10-Gy irradiation by carrying out 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, Western blots, fluorescence-activated cell sorting analysis, and immunofluorescence stainings. Terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling staining was used to detect apoptosis. RESULTS: A G2-M arrest was shown by fluorescence-activated cell sorting analysis. p53 and p21 were found to be up-regulated but were not immediately related to the arrest. The G2-M arrest was transient and the cells reentered the cell cycle still containing unrepaired cellular damage. This premature entry caused an increase of anaphase bridges, lagging chromosomal material, and multipolar mitotic spindles as visualized by propidium iodide staining and immunofluorescence staining with alpha-tubulin and gamma-tubulin antibodies. Furthermore, a dose-dependent significant increase in centrosome numbers from 12.6+/-6.6% to 67+/-5.3% was identified as well as a dose-dependent increase of polyploid cells from 2.8+/-1.3% to 17.6+/-2.1% with the highest absorbed dose of 10 Gy. These disturbances caused the cells to progress into mitotic catastrophe and a fraction of these dying cells showed apoptotic features as displayed by terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling staining 5 to 7 days after irradiation. CONCLUSION: An absorbed dose of 2.5 to 10 Gy was shown to force HeLa Hep2 cells into mitotic catastrophe and delayed apoptosis. These might be important cell death mechanisms involved in tumor growth retardation following radioimmunotherapy of solid tumors.

  • 26.
    Eriksson, David
    et al.
    Umeå University, Faculty of Medicine, Clinical Microbiology.
    Mirzaie-Joniani, Homa
    Umeå University, Faculty of Medicine, Clinical Microbiology.
    Sheikholvaezin, Ali
    Umeå University, Faculty of Medicine, Clinical Microbiology.
    Löfroth, Per-Olov
    Umeå University, Faculty of Medicine, Radiation Sciences, Radiation Physics.
    Johansson, Lennart
    Umeå University, Faculty of Medicine, Radiation Sciences, Radiation Physics.
    Åhlström-Riklund, Katrine
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Stigbrand, Torgny
    Umeå University, Faculty of Medicine, Clinical Microbiology.
    Combined low dose radio- and radioimmunotherapy of experimental HeLa Hep 2 tumours.2003In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 30, no 6, p. 895-906Article in journal (Refereed)
    Abstract [en]

    Radiation therapy of malignant tumours can be delivered by external beam radiation (RT) or radioimmunotherapy (RIT), using nuclides attached to monoclonal antibodies (mAbs). These treatment modalities have now been combined in order to investigate putative therapeutic advantages and elucidate the biological responses involved. Nude mice were transplanted subcutaneously on the back with human HeLa Hep2 tumour cells. RT (3x5 Gy) and/or 100 microg (131)I-labelled mAb H7, against placental alkaline phosphatase, or (131)I-labelled mAb TS1, against cytokeratin, was administered separately or in combination (specific activity of 120-200 MBq/mg antibody). Significant tumour growth retardation was observed both with RT alone and with RIT alone. Combining these regimens enhanced the therapeutic effects further, and a significant reduction in tumour volume could be demonstrated. The tumours were subjected to extensive histochemical and immunohistochemical investigations in order to elucidate changes in biology and histology within them. The following stainings were used: haematoxylin-eosin (morphology), Ki67 (proliferation), M30 (apoptosis), TUNEL (apoptosis) and endoglin (vascularisation). Tumours in the control group grew fast, with an average tumour doubling time of 9 days. These tumours contained large viable tumour cell masses displaying vast proliferation zones of Ki67-positive tumour cells, as well as necrotic regions and small amounts of connective tissue. Apoptotic cells could be identified both with M30 and TUNEL staining. When RT was applied, the growth rate was significantly reduced (doubling time 19 days) and typical alterations in morphology were seen, with a relative increase in connective tissue and a decrease in necrotic regions. Apoptotic cells were identified and a decrease in cell density was also observed. When RIT alone was applied, the growth parameters indicated a longer lasting growth reduction, especially when TS1 was used separately or in combination with H7. The histological appearances of these tumours were somewhat different from the RT-treated tumours, with a larger portion of intratumoural cysts. These tumours also presented a reduced tumour cell density. Dramatic effects were observed when RT was combined with RIT, with a pronounced growth reduction seen in all combination treatment groups. Pronounced tumour volume reduction was also evident in both the RT + RIT ((131)I-TS1) group and RT + RIT ((131)I-TS1/(131)I-H7) group, and in some animals no tumour remained at all. The morphology of the tumour remnants at day 22 was chaotic with a drastically changed histology, with presence of abundant cysts, low fractions of Ki67-positive cells, reduction in cell density, increased amounts of connective tissue and a decrease in necrotic regions. Again, apoptotic cells could be identified, scattered throughout the viable regions. Combining RT and RIT seems to generate an efficient treatment with convincing and long-lasting tumour growth inhibition, which is reflected in a highly aberrant histology within the tumour. Results obtained in this study indicate that both necrosis and apoptosis may be involved in the process leading to this efficient therapy of epithelially derived tumours.

  • 27.
    Eriksson, Johan
    et al.
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund Åhlström, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Similar frontal and distinct posterior cortical regions mediate visual and auditory perceptual awareness2007In: Cerebral Cortex, ISSN 1047-3211, E-ISSN 1460-2199, Vol. 17, no 4, p. 760-765Article in journal (Refereed)
    Abstract [en]

    Activity in ventral visual cortex is a consistent neural correlate of visual consciousness. However, activity in this area seems insufficient to produce awareness without additional involvement of frontoparietal regions. To test the generality of the frontoparietal response, neural correlates of auditory awareness were investigated in a paradigm that previously has revealed frontoparietal activity during conscious visual perception. A within-experiment comparison showed that frontal regions were related to both visual and auditory awareness, whereas parietal activity was correlated with visual awareness and superior temporal activity with auditory awareness. These results indicate that frontal regions interact with specific posterior regions to produce awareness in different sensory modalities.

  • 28.
    Eriksson, Johan
    et al.
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Larsson, Anne
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund Åhlström, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Nyberg, Lars
    Umeå University, Faculty of Social Sciences, Department of Psychology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Visual consciousness: dissociating the neural correlates of perceptual transitions from sustained perception with fMRI2004In: Consciousness and Cognition, ISSN 1053-8100, E-ISSN 1090-2376, Vol. 13, no 1, p. 61-72Article in journal (Refereed)
    Abstract [en]

    To investigate the possible dichotomy between the neurophysiological bases of perceptual transitions versus sustaining a particular percept over time, an fMRI study was conducted with subjects viewing fragmented pictures. Unlike most other perceptually unstable stimuli, fragmented pictures give rise to only one perceptual transition and a continuous period of sustained perception. Earlier research is inconclusive on the subject of which anatomical regions should be attributed to what temporal aspect of perception, and the aim of the present study was to shed more light on the subject. In this study occipitotemporal and fronto-parietal regions were found to be activated for both aspects. However, regions in the medial-temporal lobe were activated specifically for transitions, whereas medial and dorsolateral prefrontal regions were activated specifically for sustained perception. These results provide further support for the theory that the initial creation of perceptual awareness and upholding perceptual awareness over time are separate processes involving different brain regions.

  • 29.
    Erlandsson, Ann
    et al.
    Umeå University, Faculty of Medicine, Clinical Microbiology.
    Eriksson, David
    Umeå University, Faculty of Medicine, Clinical Microbiology.
    Johansson, Lennart
    Umeå University, Faculty of Medicine, Radiation Sciences, Radiation Physics.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Stigbrand, Torgny
    Umeå University, Faculty of Medicine, Clinical Microbiology.
    Sundström, Birgitta Elisabeth
    In vivo clearing of idiotypic antibodies with antiidiotypic antibodies and their derivatives2006In: Molecular Immunology, ISSN 0161-5890, E-ISSN 1872-9142, Vol. 43, no 6, p. 599-606Article in journal (Refereed)
    Abstract [en]

    At immunolocalization of experimental tumors, idiotypic monoclonal antibodies, such as TS1 against cytokeratin 8, can be used to carry and deposit in vivo terapeutics in the tumor. These carriers also remain in the circulation and may cause negative side-effects in other tissues. In this report, several derivatives of the antiidiotypic antibody alphaTS1 were produced and tested for their clearing capacity of the idiotypic carrier antibody TS1. Intact monoclonal alphaTS1, scFv of a alphaTS1 and alphaTS1 Fab'2 and fragments were produced by recombinant technology or by cleavage with Ficin. The scFv was tailored by use of the variable domain genes of the light and heavy chain from the hybridoma clone in combination with a (Gly4Ser)3-linker, followed by expression in E. coli. When tested for clearing capacity, the intact divalent antiidiotypic IgG was found to be the most efficient. The divalent and the monovalent Fab fragment also demonstrated significant clearing, but lower than the intact antiidiotypic IgG. The alphaTS1 scFv antibody when injected separately was not found to clear the idiotype, but could do so when preincubated with the idiotype. Rapid excretion and in vivo instability of this low molecular weight antibody fragment may be the major reasons. Similar results were obtained when the system was reversed and the 131I-labeled antiidiotype IgG was cleared with the idiotype fragment. It is concluded that both intact antiidiotypic IgG, and Fab'2 fragments are able to clear the idiotypic antibodies. The experimental data support the conclusion that the Fc parts from both the idiotype and the antiidiotype may contribute to this elimination.

  • 30.
    Farnsworth von Cederwald, Bryn
    et al.
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Johansson, Jarkko
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Karalija, Nina
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Boraxbekk, Carl-Johan
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Danish Research Center for Magnetic Resonance (DRCMR), Center for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital, Amager and Hvidovre, Copenhagen, Denmark; Institute of Sports Medicine Copenhagen (ISMC) and Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark; Institute for Clinical Medicine, Faculty of Medical and Health Sciences, University of Copenhagen, Copenhagen, Denmark.
    White matter lesion load determines exercise-induced dopaminergic plasticity and working memory gains in aging2023In: Translational Psychiatry, E-ISSN 2158-3188, Vol. 13, no 1, article id 28Article in journal (Refereed)
    Abstract [en]

    Age-related dopamine reductions have been suggested to contribute to maladaptive working memory (WM) function in older ages. One promising intervention approach is to increase physical activity, as this has been associated with plasticity of the striatal dopamine system and WM improvements, however with individual differences in efficacy. The present work focused on the impact of individual differences in white-matter lesion burden upon dopamine D2-like receptor (DRD2) availability and WM changes in response to a 6 months physical activity intervention. While the intervention altered striatal DRD2 availability and WM performance in individuals with no or only mild lesions (p < 0.05), no such effects were found in individuals with moderate-to-severe lesion severity (p > 0.05). Follow-up analyses revealed a similar pattern for processing speed, but not for episodic memory performance. Linear analyses further revealed that lesion volume (ml) at baseline was associated with reduced DRD2 availability (r = −0.41, p < 0.05), and level of DRD2 change (r = 0.40, p < 0.05). Taken together, this study underlines the necessity to consider cerebrovascular health in interventions with neurocognitive targets. Future work should assess whether these findings extend beyond measures of DRD2 availability and WM.

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  • 31.
    Flodin, Pär
    et al.
    Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR). Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Jonasson, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Boraxbekk, Carl-Johan
    Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR). Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital, Hvidovre, Denmark.
    Does Aerobic Exercise Influence Intrinsic Brain Activity? An Aerobic Exercise Intervention among Healthy Old Adults2017In: Frontiers in Aging Neuroscience, E-ISSN 1663-4365, Vol. 9, article id 267Article in journal (Refereed)
    Abstract [en]

    Previous studies have indicated that aerobic exercise could reduce age related decline in cognition and brain functioning. Here we investigated the effects of aerobic exercise on intrinsic brain activity. Sixty sedentary healthy males and females (64–78 years) were randomized into either an aerobic exercise group or an active control group. Both groups recieved supervised training, 3 days a week for 6 months. Multimodal brain imaging data was acquired before and after the intervention, including 10 min of resting state brain functional magnetic resonance imaging (rs-fMRI) and arterial spin labeling (ASL). Additionally, a comprehensive battery of cognitive tasks assessing, e.g., executive function and episodic memory was administered. Both the aerobic and the control group improved in aerobic capacity (VO2-peak) over 6 months, but a significant group by time interaction confirmed that the aerobic group improved more. Contrary to our hypothesis, we did not observe any significant group by time interactions with regard to any measure of intrinsic activity. To further probe putative relationships between fitness and brain activity, we performed post hoc analyses disregarding group belongings. At baseline, VO2-peak was negativly related to BOLD-signal fluctuations (BOLDSTD) in mid temporal areas. Over 6 months, improvements in aerobic capacity were associated with decreased connectivity between left hippocampus and contralateral precentral gyrus, and positively to connectivity between right mid-temporal areas and frontal and parietal regions. Independent component analysis identified a VO2-related increase in coupling between the default mode network and left orbitofrontal cortex, as well as a decreased connectivity between the sensorimotor network and thalamus. Extensive exploratory data analyses of global efficiency, connectome wide multivariate pattern analysis (connectome-MVPA), as well as ASL, did not reveal any relationships between aerobic fitness and intrinsic brain activity. Moreover, fitness-predicted changes in functional connectivity did not relate to changes in cognition, which is likely due to absent cross- sectional or longitudinal relationships between VO2-peak and cognition. We conclude that the aerobic exercise intervention had limited influence on patterns of intrinsic brain activity, although post hoc analyses indicated that individual changes in aerobic capacity preferentially influenced mid-temporal brain areas.

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  • 32. Garzón, Benjamín
    et al.
    Lövdén, Martin
    de Boer, Lieke
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI).
    Bäckman, Lars
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology.
    Guitart-Masip, Marc
    Role of dopamine and gray matter density in aging effects and individual differences of functional connectomes2021In: Brain Structure and Function, ISSN 1863-2653, E-ISSN 1863-2661, Vol. 226, no 3, p. 743-758Article in journal (Refereed)
    Abstract [en]

    With increasing age, functional connectomes become dissimilar across normal individuals, reflecting heterogenous aging effects on functional connectivity (FC). We investigated the distribution of these effects across the connectome and their relationship with age-related differences in dopamine (DA) D1 receptor availability and gray matter density (GMD). With this aim, we determined aging effects on mean and interindividual variance of FC using fMRI in 30 younger and 30 older healthy subjects and mapped the contribution of each connection to the patterns of age-related similarity loss. Aging effects on mean FC accounted mainly for the dissimilarity between connectomes of younger and older adults, and were related, across brain regions, to aging effects on DA D1 receptor availability. Aging effects on the variance of FC indicated a global increase in variance with advancing age, explained connectome dissimilarity among older subjects and were related to aging effects on variance of GMD. The relationship between aging and the similarity of connectomes can thus be partly explained by age differences in DA modulation and gray matter structure.

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  • 33. Gatidis, Sergios
    et al.
    Beyer, Thomas
    Becker, Minerva
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Nikolaou, Konstantin
    Cyran, Clemens
    Pfannenberg, Christina
    State of affairs of hybrid imaging in Europe: two multi-national surveys from 20172019In: Insights into Imaging, E-ISSN 1869-4101, Vol. 10, no 1, article id 57Article in journal (Refereed)
    Abstract [en]

    Objectives: To assess the current state of hybrid imaging in Europe with respect to operations, reading and reporting, as well as qualification and training.

    Methods: The first survey (LOCAL) was sent to the heads of the departments of radiology and nuclear medicine in Europe in 2017, including 15 questions regarding the organisation of hybrid imaging operations, reporting strategies for PET/CT and the existence of relevant training programmes. The second survey (NATIONAL) consisted of 10 questions and was directed to the national ministries of health of 37 European countries addressing combined training options in radiology and nuclear medicine.

    Results: In the LOCAL survey, 61 valid responses from 26 European countries were received. In almost half of the institutions, hybrid imaging was performed within a single department, mainly in nuclear medicine departments (31%). In half of the centres (51%), PET/CT reports were performed jointly, while in 20% of the centres, reporting was performed by nuclear medicine physicians. Radiologists were responsible for presenting hybrid imaging results in clinical boards in 34% of responding sites. Integrated hybrid imaging training was available in 41% sites. In the NATIONAL survey, responses from 34 countries were received and demonstrated a heterogeneous landscape of official training possibilities in radiology and nuclear medicine with limited opportunities for additional qualifications in hybrid imaging.

    Conclusions: The results of these surveys demonstrate a notable heterogeneity in the current practice of hybrid imaging throughout Europe. This heterogeneity exists despite the general consensus that strong professional cooperation is required in order to ensure high clinical quality and to strengthen the clinical role of hybrid imaging.

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  • 34. Glimelius, Bengt
    et al.
    Melin, Beatrice
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Enblad, Gunilla
    Alafuzoff, Irina
    Beskow, Anna
    Ahlström, Håkan
    Bill-Axelson, Anna
    Birgisson, Helgi
    Björ, Ove
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Edqvist, Per-Henrik
    Hansson, Tony
    Helleday, Thomas
    Hellman, Per
    Henriksson, Kerstin
    Hesselager, Göran
    Hultdin, Magnus
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Häggman, Michael
    Höglund, Martin
    Jonsson, Håkan
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Larsson, Chatarina
    Lindman, Henrik
    Ljuslinder, Ingrid
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Mindus, Stephanie
    Nygren, Peter
    Pontén, Fredrik
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Rosenquist, Richard
    Sandin, Fredrik
    Schwenk, Jochen M.
    Stenling, Roger
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Stålberg, Karin
    Stålberg, Peter
    Sundström, Christer
    Thellenberg Karlsson, Camilla
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Westermark, Bengt
    Bergh, Anders
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Claesson-Welsh, Lena
    Palmqvist, Richard
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Sjöblom, Tobias
    U-CAN: a prospective longitudinal collection of biomaterials and clinical information from adult cancer patients in Sweden2018In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 57, no 2, p. 187-194Article in journal (Refereed)
    Abstract [en]

    Background: Progress in cancer biomarker discovery is dependent on access to high-quality biological materials and high-resolution clinical data from the same cases. To overcome current limitations, a systematic prospective longitudinal sampling of multidisciplinary clinical data, blood and tissue from cancer patients was therefore initiated in 2010 by Uppsala and Umea Universities and involving their corresponding University Hospitals, which are referral centers for one third of the Swedish population.

    Material and Methods: Patients with cancer of selected types who are treated at one of the participating hospitals are eligible for inclusion. The healthcare-integrated sampling scheme encompasses clinical data, questionnaires, blood, fresh frozen and formalin-fixed paraffin-embedded tissue specimens, diagnostic slides and radiology bioimaging data.

    Results: In this ongoing effort, 12,265 patients with brain tumors, breast cancers, colorectal cancers, gynecological cancers, hematological malignancies, lung cancers, neuroendocrine tumors or prostate cancers have been included until the end of 2016. From the 6914 patients included during the first five years, 98% were sampled for blood at diagnosis, 83% had paraffin-embedded and 58% had fresh frozen tissues collected. For Uppsala County, 55% of all cancer patients were included in the cohort.

    Conclusions: Close collaboration between participating hospitals and universities enabled prospective, longitudinal biobanking of blood and tissues and collection of multidisciplinary clinical data from cancer patients in the U-CAN cohort. Here, we summarize the first five years of operations, present U-CAN as a highly valuable cohort that will contribute to enhanced cancer research and describe the procedures to access samples and data.

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  • 35.
    Grefve, Josefine
    et al.
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Söderkvist, Karin
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Gunnlaugsson, Adalsteinn
    Department of Hematology, Oncology and Radiation Physics, Skane University Hospital, Lund University, Lund, Sweden.
    Sandgren, Kristina
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Jonsson, Joakim
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Keeratijarut Lindberg, Angsana
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Nilsson, Erik
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Axelsson, Jan
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Bergh, Anders
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Zackrisson, Björn
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Moreau, Mathieu
    Department of Hematology, Oncology and Radiation Physics, Skane University Hospital, Lund University, Lund, Sweden.
    Thellenberg-Karlsson, Camilla
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Olsson, Lars.E.
    Department of Translational Medicine, Medical Radiation Physics, Lund University, Malmö, Sweden.
    Widmark, Anders
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Riklund, Katrine
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Blomqvist, Lennart
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Berg Loegager, Vibeke
    Department of Radiology, Copenhagen University Hospital in Herlev, Herlev, Denmark.
    Strandberg, Sara
    Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Nyholm, Tufve
    Umeå University, Faculty of Medicine, Department of Diagnostics a