| 1. |
- Eriksson, Anders D, et al.
(författare)
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Alginate impressions for fixed prosthodontics : A 20 year follow up study
- 2004
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Ingår i: Swedish Dental Journal. - 0347-9994. ; 28:2, s. 53-59
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to estimate whether the survival ratios after 20 years of fixed prosthodontics made of alginate impressions was higher, equivalent or lower, compared to the survival ratios, shown in studies, where different impression materia Is were used. 151 females and 104 males were screened regarding the condition and age of the restorations at the an nu a I check-up in one of the authors surgeries. Average ages were 55 and 54 years respectively, when the fixed prosthodontics were seated. A total of 1.271 units were produced during the twenty years, 911 abutment teeth and 360 pontics. The type of prosthetic work was divided into three groups: 1) larger fixed prosthodontics 6-14 units (469), 2) smaller fixed prosthodontics 2-5 units (541) and 3) single crowns (261). The results show that alginate impressions can produce fixed prosthodontics with survival ratios similar to those presented in other studies, after 5 years (99%) 10 years (93-96%) and 15 years (74-96%). After 20 years the survival ratio was 61-63%. In conclusion, fixed prosthodontics made according to the syringe-tray alginate impression method may have the same success rates after 20 years compared to that of fixed prosthodontics presented in previous longitudinal clinical studies where other impression materials had been used. In this study, caries and root fractures were the main reasons for removing abutment teeth and pontics.
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| 2. |
- Eriksson, Olof, et al.
(författare)
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Quantitative Imaging of Serotonergic Biosynthesis and Degradation in the Endocrine Pancreas
- 2014
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Ingår i: Journal of Nuclear Medicine. - : Society of Nuclear Medicine. - 0161-5505 .- 1535-5667 .- 2159-662X. ; 55:3, s. 460-465
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Tidskriftsartikel (refereegranskat)abstract
- Serotonergic biosynthesis in the endocrine pancreas, of which the islets of Langerhans is the major constituent, has been implicated in insulin release and β cell proliferation. In this study, we investigated the feasibility of quantitative noninvasive imaging of the serotonergic metabolism in the pancreas using the PET tracer (11)C-5-hydroxy-l-tryptophan ((11)C-5-HTP).METHODS: Uptake of (11)C-5-HTP, and its specificity for key enzymes in the serotonergic metabolic pathway, was assessed in vitro (INS-1 and PANC1 cells and human islet and exocrine preparations) and in vivo (nonhuman primates and healthy and diabetic rats).RESULTS: In vitro tracer uptake in endocrine cells (INS-1 and human islets), but not PANC1 and exocrine cells, was mediated specifically by intracellular conversion into serotonin. Pancreatic uptake of (11)C-5-HTP in nonhuman primates was markedly decreased by inhibition of the enzyme dopa decarboxylase, which converts (11)C-5-HTP to (11)C-serotonin and increased after inhibition of monoamine oxidase-A, the main enzyme responsible for serotonin degradation. Uptake in the rat pancreas was similarly modulated by inhibition of monoamine oxidase-A and was reduced in animals with induced diabetes.CONCLUSION: The PET tracer (11)C-5-HTP can be used for quantitative imaging of the serotonergic system in the endocrine pancreas.
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| 3. |
- Eriksson, Olof, et al.
(författare)
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The Positron Emission Tomography ligand [11C]5-Hydroxy-Tryptophan can be used as a surrogate marker for the human endocrine pancreas
- 2014
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 63:10, s. 3428-3437
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Tidskriftsartikel (refereegranskat)abstract
- In humans a well-developed serotonin system is localized to the pancreatic islets while being absent in exocrine pancreas. Assessment of pancreatic serotonin biosynthesis could therefore be used to estimate the human endocrine pancreas. Proof of concept was tested in a prospective clinical trial by comparisons of type 1 diabetic (T1D) patients, with extensive reduction of beta cells, with healthy volunteers (HV).C-peptide negative (i.e. insulin-deficient) T1D subjects (n=10) and HV (n=9) underwent dynamic Positron Emission Tomography with the radiolabeled serotonin precursor [(11)C]5-Hydroxy-Tryptophan ([(11)C]5-HTP).A significant accumulation of [(11)C]5-HTP was obtained in the pancreas of the HV, with large inter-individual variation. A substantial and highly significant reduction (66%) in the pancreatic uptake of [(11)C]5-HTP in T1D subjects was observed, and this was most evident in the corpus and caudal regions of the pancreas where beta-cells normally are the major constituent of the islets.[(11)C]5-HTP retention in the pancreas was reduced in T1D compared to non-diabetic subjects. Accumulation of [(11)C]5-HTP in the pancreas of both HV and subjects with T1D were in agreement with previously reported morphological observations on the beta cell volume implying that [(11)C]5-HTP retention is a useful non-invasive surrogate marker for the human endocrine pancreas.
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| 4. |
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| 5. |
- Burkert, Till, et al.
(författare)
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Giant Magnetic Anisotropy in Tetragonal FeCo Alloys
- 2004
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 93:2, s. 027203-
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Tidskriftsartikel (refereegranskat)abstract
- The magnetic anisotropy energy (MAE) of hcp Gd was calculated from first principles using the full-potential linear muffin-tin orbital method. It was found that the principal contributions to the MAE are the dipole-dipole interaction between the localized 4f spins and the spin-orbit interaction of the valence band states. The dipole contribution has the form 1/2K(1)(d)(1-cos 2 theta), where theta is the angle between the magnetization direction and the c axis. The contribution of the spin-orbit interaction is shown to arise from the polarization of the conduction band that becomes exchange split due to exchange interaction with the localized 4f electrons. We argue that this leads to significant contributions from higher order anisotropy constants. An imposed reduced 4f moment leads to a repopulation of the electronic states at the Fermi level and a reduced exchange splitting of the valence states, which we demonstrate leads to a modification of the MAE. This modification is in qualitative agreement with the observed temperature dependence of the MAE. In addition, the dependence of the MAE on the c/a ratio has been studied.
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| 6. |
- Cheung, Pierre, et al.
(författare)
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[18F]MK-7246 for Positron Emission Tomography Imaging of the Beta-Cell Surface Marker GPR44
- 2023
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Ingår i: Pharmaceutics. - : MDPI. - 1999-4923. ; 15:2
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Tidskriftsartikel (refereegranskat)abstract
- The progressive loss of beta-cell mass is a hallmark of diabetes and has been suggested as a complementary approach to studying the progression of diabetes in contrast to the beta-cell function. Non-invasive nuclear medicinal imaging techniques such as Positron Emission Tomography using radiation emitting tracers have thus been suggested as more viable methodologies to visualize and quantify the beta-cell mass with sufficient sensitivity. The transmembrane G protein-coupled receptor GPR44 has been identified as a biomarker for monitoring beta-cell mass. MK-7246 is a GPR44 antagonist that selectively binds to GPR44 with high affinity and good pharmacokinetic properties. Here, we present the synthesis of MK-7246, radiolabeled with the positron emitter fluorine-18 for preclinical evaluation using cell lines, mice, rats and human pancreatic cells. Here, we have described a synthesis and radiolabeling method for producing [18F]MK-7246 and its precursor compound. Preclinical assessments demonstrated the strong affinity and selectivity of [18F]MK-7246 towards GPR44. Additionally, [18F]MK-7246 exhibited excellent metabolic stability, a fast clearance profile from blood and tissues, qualifying it as a promising radioactive probe for GPR44-directed PET imaging.
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| 7. |
- Cheung, Pierre, et al.
(författare)
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PET Imaging of GPR44 by Antagonist [C-11]MK-7246 in Pigs
- 2021
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Ingår i: Biomedicines. - : MDPI. - 2227-9059. ; 9:4
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Tidskriftsartikel (refereegranskat)abstract
- A validated imaging marker for beta-cell mass would improve understanding of diabetes etiology and enable new strategies in therapy development. We previously identified the membrane-spanning protein GPR44 as highly expressed and specific to the beta cells of the pancreas. The selective GPR44 antagonist MK-7246 was radiolabeled with carbon-11 and the resulting positron-emission tomography (PET) tracer [C-11]MK-7246 was evaluated in a pig model and in vitro cell lines. The [C-11]MK-7246 compound demonstrated mainly hepatobiliary excretion with a clearly defined pancreas, no spillover from adjacent tissues, and pancreatic binding similar in magnitude to the previously evaluated GPR44 radioligand [C-11]AZ12204657. The binding could be blocked by preadministration of nonradioactive MK-7246, indicating a receptor-binding mechanism. [C-11]MK-7246 showed strong potential as a PET ligand candidate for visualization of beta-cell mass (BCM) and clinical translation of this methodology is ongoing.
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| 8. |
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| 9. |
- Cheung, Pierre, et al.
(författare)
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Preclinical evaluation of Affibody molecule for PET imaging of human pancreatic islets derived from stem cells
- 2023
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Ingår i: EJNMMI Research. - : Springer Nature. - 2191-219X. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Beta-cell replacement methods such as transplantation of isolated donor islets have been proposed as a curative treatment of type 1 diabetes, but widespread application is challenging due to shortages of donor tissue and the need for continuous immunosuppressive treatments. Stem-cell-derived islets have been suggested as an alternative source of beta cells, but face transplantation protocols optimization difficulties, mainly due to a lack of available methods and markers to directly monitor grafts survival, as well as their localization and function. Molecular imaging techniques and particularly positron emission tomography has been suggested as a tool for monitoring the fate of islets after clinical transplantation. The integral membrane protein DGCR2 has been demonstrated to be a potential pancreatic islet biomarker, with specific expression on insulin-positive human embryonic stem-cell-derived pancreatic progenitor cells. The candidate Affibody molecule ZDGCR2:AM106 was radiolabeled with fluorine-18 using a novel click chemistry-based approach. The resulting positron emission tomography tracer [18F]ZDGCR2:AM106 was evaluated for binding to recombinant human DGCR2 and cryosections of stem-cell-derived islets, as well as in vivo using an immune-deficient mouse model transplanted with stem-cell-derived islets. Biodistribution of the [18F]ZDGCR2:AM106 was also assessed in healthy rats and pigs. Results: [18F]ZDGCR2:AM106 was successfully synthesized with high radiochemical purity and yield via a pretargeting approach. [18F]ZDGCR2:AM106 retained binding to recombinant human DCGR2 as well as to cryosectioned stem-cell-derived islets, but in vivo binding to native pancreatic tissue in both rat and pig was low. However, in vivo uptake of [18F]ZDGCR2:AM106 in stem-cell-derived islets transplanted in the immunodeficient mice was observed, albeit only within the early imaging frames after injection of the radiotracer. Conclusion: Targeting of DGCR2 is a promising approach for in vivo detection of stem-cell-derived islets grafts by molecular imaging. The synthesis of [18F]ZDGCR2:AM106 was successfully performed via a pretargeting method to label a site-specific covalently bonded fluorine-18 to the Affibody molecule. However, the rapid washout of [18F]ZDGCR2:AM106 from the stem-cell-derived islets graft indicates that dissociation kinetics can be improved. Further studies using alternative binders of similar classes with improved binding potential are warranted.
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| 10. |
- Damberg, Mattias, et al.
(författare)
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Investigation of transcription factor AP-2 beta genotype in women with premenstrual dysphoric disorder.
- 2005
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Ingår i: Neuroscience letters. - : Elsevier BV. - 0304-3940. ; 377:1, s. 49-52
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Tidskriftsartikel (refereegranskat)abstract
- It has repeatedly been shown that the serotonergic system is involved in the symptomatology of premenstrual dysphoric disorder (PMDD). Women with PMDD are reported to differ from symptom-free controls with regard to serotonin-related biological markers. Evidence from family and twin studies suggests a genetic contribution to the aetiology of PMDD. The expression of human transcription factor AP-2beta in neural crest cell lineages and neuroectodermal cells suggests that this protein may be of importance for functional characteristics of neurons by regulating the expression of target genes. Within the monoaminergic systems, several genes have binding sites for AP-2beta in regulatory regions, suggesting an involvement of AP-2beta in these systems. The gene encoding AP-2beta is located on chromosome 6p12-p21.1 and includes a polymorphic region consisting of a variable number of [CAAA] repeats located in the second intron. We have earlier shown that AP-2beta genotype is associated with serotonergic phenotypes and that brainstem levels of AP-2beta correlate positively to serotonin metabolism in rat frontal cortex. The aim of this study was to investigate the relationship between PMDD and transcription factor AP-2beta genotype. The participants included 176 women with PMDD and 91 healthy controls. Genotyping was performed by polymerase chain reactions. We did not observe any differences in AP-2beta genotype frequencies between PMDD subjects and controls. Our results suggest that AP-2beta genotype is not a risk factor for PMDD. To our knowledge, this is the first study investigating transcription factor AP-2beta genotype in women with PMDD. Hence, these results should be considered preliminary until replicated.
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| 11. |
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| 12. |
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| 13. |
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| 14. |
- Eriksson, Britt, 1967-, et al.
(författare)
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Fat-free mass hydration in newborns : assessment and implications for body composition studies
- 2011
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Ingår i: Acta Paediatrica. - Hoboken, USA : Wiley-Blackwell. - 0803-5253 .- 1651-2227. ; 100:5, s. 680-686
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Tidskriftsartikel (refereegranskat)abstract
- Equipment (Pea Pod) for assessing infant body density accurately and conveniently has recently become available. This density can be converted to body composition using the “Fomon” or the “Butte” model. These models differ regarding the water content in fat-free mass (hydration factor, HF). We assessed HF and its biological variability in newborns and compared results calculated using the two models at one and 12 weeks. Body volume and body weight were measured in 12 infants less than 10 days old using Pea Pod. Their total body water was assessed using isotope dilution. Their HF was found to be 80.9% with low biological variability (0.81% of average HF). Further, Pea Pod was used to assess body density of 108 infants at one and 12 weeks of age. Values for body fat (%) calculated using the “Butte” model were significantly lower than when using the “Fomon” model at one week (p<0.05) and 12 weeks (p<0.01). The difference between the two models was particularly large at one week, probably due to their different HF-values. Our HF-value is in agreement with that in the “Fomon” model and our results support the conclusion that this model is preferable when calculating body composition in infants.
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| 15. |
- Eriksson, Daniel, et al.
(författare)
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Cytokine Autoantibody Screening in the Swedish Addison Registry Identifies Patients With Undiagnosed APS1
- 2018
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 103:1, s. 179-186
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Tidskriftsartikel (refereegranskat)abstract
- Context: Autoimmune polyendocrine syndrome type 1 (APS1) is a monogenic disorder that features autoimmune Addison disease as a major component. Although APS1 accounts for only a small fraction of all patients with Addison disease, early identification of these individuals is vital to prevent the potentially lethal complications of APS1.Objective: To determine whether available serological and genetic markers are valuable screening tools for the identification of APS1 among patients diagnosed with Addison disease.Design: We systematically screened 677 patients with Addison disease enrolled in the Swedish Addison Registry for autoantibodies against interleukin-22 and interferon-α4. Autoantibody-positive patients were investigated for clinical manifestations of APS1, additional APS1-specific autoantibodies, and DNA sequence and copy number variations of AIRE.Results: In total, 17 patients (2.5%) displayed autoantibodies against interleukin-22 and/or interferon-α4, of which nine were known APS1 cases. Four patients previously undiagnosed with APS1 fulfilled clinical, genetic, and serological criteria. Hence, we identified four patients with undiagnosed APS1 with this screening procedure.Conclusion: We propose that patients with Addison disease should be routinely screened for cytokine autoantibodies. Clinical or serological support for APS1 should warrant DNA sequencing and copy number analysis of AIRE to enable early diagnosis and prevention of lethal complications.
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| 16. |
- Eriksson, D, et al.
(författare)
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Extended exome sequencing identifies BACH2 as a novel major risk locus for Addison's disease
- 2016
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 286:6, s. 595-608
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Autoimmune disease is one of the leading causes of morbidity and mortality worldwide. In Addison's disease, the adrenal glands are targeted by destructive autoimmunity. Despite being the most common cause of primary adrenal failure, little is known about its aetiology.METHODS: To understand the genetic background of Addison's disease, we utilized the extensively characterized patients of the Swedish Addison Registry. We developed an extended exome capture array comprising a selected set of 1853 genes and their potential regulatory elements, for the purpose of sequencing 479 patients with Addison's disease and 1394 controls.RESULTS: We identified BACH2 (rs62408233-A, OR = 2.01 (1.71-2.37), P = 1.66 × 10(-15) , MAF 0.46/0.29 in cases/controls) as a novel gene associated with Addison's disease development. We also confirmed the previously known associations with the HLA complex.CONCLUSION: Whilst BACH2 has been previously reported to associate with organ-specific autoimmune diseases co-inherited with Addison's disease, we have identified BACH2 as a major risk locus in Addison's disease, independent of concomitant autoimmune diseases. Our results may enable future research towards preventive disease treatment.
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| 17. |
- Eriksson, Jenny, 1975-, et al.
(författare)
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Skattning av cykeltrafikarbetet : en pilotstudie i tre kommuner
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Nationellt (via gång- cykel- och kollektivtrafikmålet), regionalt och i många av Sveriges kommuner finns målsättningar om ökad cykling. Dessa målsättningar är dock svåra att följa upp, då cykeltrafikens storlek inte mäts och följs upp. Med de metoder som används idag för flödesmätningar är det inte möjligt att skatta cykeltrafikarbetet i hela kommunen, då flödesmätningarna inte genomförs på systemnivå för det cykelbara vägnätet. Det övergripande syftet med pilotstudien är att ta fram en accepterad, tillförlitlig, tillämpbar och enhetlig metod för att skatta cykeltrafikarbetet i kommunen genom flödesmätningar. Kommunerna Stockholm, Uppsala och Östersund ingår i pilotstudien. Det genomfördes 135 veckomätningar i varje kommun; 100 på gång- och cykelvägnätet och 35 i blandtrafik, uppdelat på fem etapper. De kontinuerligt mätta flödespunkterna användes som information för uppräkning på helårsnivå. Cykelvägnätet omfattar inte grusvägar, enskilda väghållare och vägar med skyltad hastighet 80 km/h och högre. Länkarna delades in i stratum, där det i varje stratum gjordes ett systematiskt urval på den totala länklängden. Skattningsmetoden tog hänsyn till både rum och tid. Under det brutna året vecka 35 år 2020 till vecka 34 år 2021 cyklades det 145±43 miljoner kilometer i Stockholm, 59±23 miljoner kilometer i Uppsala och 9±3 miljoner kilometer i Östersund. Osäkerheten i skattningen, utgör mellan 30 och 40 procent av punktskattningen. Det är en ganska stor osäkerhet i skattningen, men tillräckligt liten för att se att det exempelvis är skillnader mellan kommunerna. Något som framkommit i denna studie är att cyklandet i blandtrafik inte är försumbar och kommunerna bör ha detta i beaktande. För att studien ska komma till sin rätt bör den upprepas en gång till i minst en av dessa kommuner.
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| 18. |
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| 19. |
- Eriksson, Jonas, et al.
(författare)
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Synthesis and preclinical evaluation of the CRTH2 antagonist [11C]MK-7246 as a novel PET tracer and potential surrogate marker for pancreatic beta-cell mass
- 2019
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Ingår i: Nuclear Medicine and Biology. - : Elsevier BV. - 0969-8051 .- 1872-9614. ; 71, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: MK-7246 is a potent and selective antagonist for chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2). Within the pancreas CRTH2 is selectively expressed in pancreatic β-cells where it is believed to play a role in insulin release. Reduction in β-cell mass and insufficient insulin secretion in response to elevated blood glucose levels is a hallmark for type 1 and type 2 diabetes. Reported here is the synthesis of [11C]MK-7246 and initial preclinical evaluation towards CRTH2 imaging. The aim is to develop a method to quantify β-cell mass with PET and facilitate non-invasive studies of disease progression in individuals with type 2 diabetes.Methods: The precursor N-desmethyl-O-methyl MK-7246 was synthesized in seven steps and subjected to methylation with [11C]methyl iodide followed by hydrolysis to obtain [11C]MK-7246 labelled in the N-methyl position. Preclinical evaluation included in vitro radiography and immune-staining performed in human pancreatic biopsies. Biodistribution studies were performed in rat by PET-MRI and in pig by PET-CT imaging. The specific tracer uptake was examined in pig by scanning before and after administration of MK-7246 (1 mg/kg). Predicted dosimetry of [11C]MK-7246 in human males was estimated based on the biodistribution in rat.Results: [11C]MK-7246 was obtained with activities sufficient for the current investigations (270±120 MBq) and a radiochemical purity of 93±2%. The tracer displayed focal binding in areas with insulin positive islet of Langerhans in human pancreas sections. Baseline uptake in pig was significantly reduced in CRTH2-rich areas after administration of MK-7246; pancreas (66% reduction) and spleen (88% reduction). [11C]MK-7246 exhibited a safe human predicted dosimetry profile as extrapolated from the rat biodistribution data.Conclusions: Initial preclinical in vitro and in vivo evaluation of [11C]MK-7246 show binding and biodistribution properties suitable for PET imaging of CRTH2. Further studies are warranted to assess its potential in β-cell mass imaging and CRTH2 drug development.
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| 20. |
- Eriksson, Olof, et al.
(författare)
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Detection of Metastatic Insulinoma by Positron Emission Tomography with [(68)Ga]Exendin-4 - : a case report
- 2014
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 99:5, s. 1519-1524
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Tidskriftsartikel (refereegranskat)abstract
- Context: Insulinomas are the most common cause of endogenous hyperinsulinaemic hypoglycaemia in non-diabetic adult patients. They are usually benign and curative surgery is the "gold standard" treatment if they can be localized. Malignant insulinomas are seen in less than 10% and their prognosis is poor. The Glucagon Like Peptide-1 receptor (GLP-1R) is markedly upregulated in insulinomas - especially benign lesions which are difficult to localize with current imaging techniques.Objective:To assess the possibility of the detection of primary and metastatic insulinoma by PET using [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4 ([(68)Ga]Exendin-4) in a patient with severe hypoglycemia.Design:Dynamic and static PET/CT examination of a patient using [68Ga]Exendin-4.Setting:Uppsala University Hospital, Uppsala, Sweden.Patients:A patient presented with hypoglycemia requiring continuous intravenous glucose infusions. A pancreatic insulinoma was suspected and an exploratory laparotomy was urgently performed. At surgery, a tumor in the pancreatic tail with an adjacent metastasis was found and a distal pancreatic resection (plus splenectomy) and removal of lymph node was performed. Histopathology showed a WHO grade II insulinoma. Postoperatively hypoglycemia persisted but a PET/CT examination using the neuroendocrine marker [(11)C]-5-hydroxy-L-tryptophan was negative.Interventions:The patient was administered with [(68)Ga]Exendin-4 and examined by dynamic PET over the liver and pancreas.Main Outcome Measures:N/AResults:The stable GLP-1 analogue Exendin-4 was labeled with (68)Ga for PET imaging of GLP-1R expressing tumors. The patient was examined by [(68)Ga]Exendin-4-PET/CT which confirmed several small GLP-1R positive lesions in the liver and a lymph node that could not be conclusively identified by other imaging techniques. The results obtained from the [(68)Ga]Exendin-4-PET/CT examination provided the basis for continued systemic treatment.Conclusion:The results of the [(68)Ga]Exendin-4-PET/CT examination governed the treatment strategy of this particular patient and demonstrated the potential of this technique for future management of patients with this rare, but potentially fatal disease.
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| 21. |
- Eriksson, Olle, et al.
(författare)
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Many-body projector orbitals for electronic structure theory of strongly correlated electrons
- 2005
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Ingår i: INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY. - : Wiley. - 0020-7608 .- 1097-461X. ; 105:2, s. 160-
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Tidskriftsartikel (refereegranskat)abstract
- We describe a technique to evaluate projector functions to be used, e.g., in self-interaction corrected versions of the Kohn-Sham equation (or in the LSDA+U method). The projector functions reproduce by construction the expectation values of spin and orbital moments (or any other property one is interested in) for the atomic many-body state. We therefore refer to these projector functions as many-body projector orbitals (MBPO). We describe how, once these projector states have been calculated, one can use them in any electronic structure method for a solid or molecule, to calculate ground-state properties of materials with strongly correlated states.
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| 22. |
- Eriksson, Olle, 1954-, et al.
(författare)
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Ovarian morphology in premenstrual dysphoria
- 2012
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Ingår i: Psychoneuroendocrinology. - : Elsevier BV. - 0306-4530 .- 1873-3360. ; 37:6, s. 742-751
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Tidskriftsartikel (refereegranskat)abstract
- Ovarian cyclicity is a prerequisite for premenstrual dysphoria (PMD), as illustrated by the fact that this condition is effectively eliminated by ovariectomy or by treatment with a GnRH agonist. Despite the possibility of differences in ovarian function between women with and without PMD, no study comparing ovarian morphology in these two groups has ever been published. Fifty-two women were recruited for this study; 26 had premenstrual dysphoria, fulfilling criteria slightly modified from those of the premenstrual dysphoric disorder, and 26 were asymptomatic age-matched controls. Ovarian morphology was assessed using transvaginal 7MHz ultrasonography on day 5 after the start of menses, and venous blood was sampled for hormone analysis on days 3 and 8, the expected day of ovulation, and day -4 of the menstrual cycle. There were no significant differences between the groups with respect to the prevalence of polycystic ovaries (PCO), the total number of follicles, the total ovarian volume or serum levels of androgen hormones. In addition, serum free testosterone levels in late premenstrual phase showed an inverse association to premenstrual symptoms of irritability and a similar inverse association trend to symptoms of depressed mood. Unexpectedly, the prevalence of ovaries with fewer than five antral or growing follicles was significantly higher in women with PMD than in controls (p=0.016). While the results do not support a role for PCO or androgen hormones in eliciting late luteal phase irritability, the possible relationship between oligofollicular ovaries and PMD deserves further study.
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| 23. |
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| 24. |
- Eriksson, Therese, et al.
(författare)
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Crystal and magnetic structure of Mn3IrSi
- 2004
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 69:5, s. 054422-
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Tidskriftsartikel (refereegranskat)abstract
- A new ternary Ir-Mn-Si phase with stoichiometry Mn3IrSi has been synthesized and found to crystallize in the cubic AlAu4-type structure, space group P213 with Z=4, which is an ordered form of the β-Mn structure. The unit cell dimension was determined by x-ray powder diffraction to a=6.4973(3)Å. In addition to the crystal structure, we have determined the magnetic structure and properties using superconducting quantum interference device magnetometry and Rietveld refinements of neutron powder diffraction data. A complex noncollinear magnetic structure is found, with magnetic moments of 2.97(4)μB at 10 K only on the Mn atoms. The crystal structure consists of a triangular network built up by Mn atoms, on which the moments are rotated 120° around the triangle axes. The magnetic unit cell is the same as the crystallographic and carries no net magnetic moment. The Néel temperature was determined to be 210 K. A first-principles study, based on density functional theory in a general noncollinear formulation, reproduces the experimental results with good agreement. The observed magnetic structure is argued to be the result of frustration of antiferromagnetic couplings by the triangular geometry.
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| 25. |
- Eriksson, Therese, et al.
(författare)
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Crystal structure and magnetic properties of the new phase Mn3IrSi
- 2004
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Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853. ; :272-276, s. 823-825
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Tidskriftsartikel (refereegranskat)abstract
- A new phase in the ternary Ir–Mn–Si system has been synthesised. From powder neutron diffraction data the crystal structure was determined to be of the AlAu4 type and to be described in the cubic space group P213 with the unit cell a=6.4973(3) Å. Susceptibility measurements using a SQUID-magnetometer showed a transition typical of antiferromagnetism, with TN=210 K. Low temperature antiferromagnetic order is confirmed by extra peaks in neutron diffractograms recorded at 10 and 80 K.
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| 26. |
- Eriksson, Therese, et al.
(författare)
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Cycloidal magnetic order in the compound IrMnSi
- 2005
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 71:17
-
Tidskriftsartikel (refereegranskat)abstract
- A new compound, IrMnSi, has been synthesized, and its crystal structure and magnetic properties have been investigated by means of neutron powder diffraction, magnetization measurements, and first-principles theory. The crystal structure is found to be of the TiNiSi type (ordered Co2P, space groupPnma). The Mn-projected electronic states are situated at the Fermi level, giving rise to metallic binding, whereas a certain degree of covalent character is observed for the chemical bond between the Ir and Si atoms. A cycloidal, i.e., noncollinear, magnetic structure was observed below 460 K, with the propagation vector q=[0,0,0.4530(5)] at 10 K. The magnetism is dominated by large moments on the Mn sites, 3.8μB∕atom from neutron diffraction. First-principles theory reproduces the propagation vector of the experimental magnetic structure as well as the angles between the Mn moments. The calculations further result in a magnetic moment of 3.2μB for the Mn atoms, whereas the Ir and Si moments are negligible, in agreement with observations. A calculation that more directly incorporates electron-electron interactions improves the agreement between the theoretical and experimental magnetic moments. A band mechanism is suggested to explain the observed magnetic order.
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| 27. |
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| 28. |
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| 29. |
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| 30. |
- Eriksson, Therese, et al.
(författare)
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Structural and magnetic characterization of Mn3IrGe and Mn3Ir(Si1-xGex) : experiments and theory
- 2004
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Ingår i: Journal of Solid State Chemistry. - : Elsevier BV. - 0022-4596 .- 1095-726X. ; 177:11, s. 4058-4066
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Tidskriftsartikel (refereegranskat)abstract
- The Structural and magnetic propertiesof a new ternary Ir-Mn-Ge phase, Mn3IrGe, as well as the solid solution Mn3Ir(Si1_xGex), O ordering is found below a critical temperature of about 225 K. The magnetic structure is noncollinear, as a result of frustrated magnetic interactions on a triangular network of Mn atoms, on which the moments rotate 120° around the triangle axes. The magnitude of the magnetic moment at 10 K is 3.39(4) µB for Mn3IrGe. The theoretical calculations reproduce with very good accuracy the magnitudes as well as the directions of the experimentally observed magnetic moments.
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| 31. |
- Etz, Corina, et al.
(författare)
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Atomistic spin dynamics and surface magnons
- 2015
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Ingår i: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 27:24
-
Forskningsöversikt (refereegranskat)abstract
- Atomistic spin dynamics simulations have evolved to become a powerful and versatile tool for simulating dynamic properties of magnetic materials. It has a wide range of applications, for instance switching of magnetic states in bulk and nano-magnets, dynamics of topological magnets, such as skyrmions and vortices and domain wall motion. In this review, after a brief summary of the existing investigation tools for the study of magnons, we focus on calculations of spin-wave excitations in low-dimensional magnets and the effect of relativistic and temperature effects in such structures. In general, we find a good agreement between our results and the experimental values. For material specific studies, the atomistic spin dynamics is combined with electronic structure calculations within the density functional theory from which the required parameters are calculated, such as magnetic exchange interactions, magnetocrystalline anisotropy, and Dzyaloshinskii-Moriya vectors.
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| 32. |
- Fang, C.M., et al.
(författare)
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General trend of the mechanical properties of the ternary carbides M3SiC2 (M=transition metal)
- 2006
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 74:5, s. 054106-
-
Tidskriftsartikel (refereegranskat)abstract
- We present results from first-principles calculations of ternary transition metal carbides in the M3SiC2 series (where M=early transition metal). We predict structural and mechanical properties of these new MN+1AXN phases. The bulk modulus of the ternary carbides, M3SiC2, are in the calculations found to be proportional to the bulk modulus of the corresponding binary carbides, MC. We have analyzed this behavior using a simple, nearest-neighbor bond model, as well as from first-principles total energy calculations and have found that it is caused by a considerably weaker M-Si bond compared to the M-C bond.
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| 33. |
- Forsman, Åsa, 1972-, et al.
(författare)
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Prognosintervall för antal allvarligt skadade i vägtrafikolyckor
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet med denna studie har varit att visa hur stor osäkerheten är i prognoserna för antalet allvarligt och mycket allvarligt skadade personer inom olika delpopulationer, med avseende på geografiska områden, trafikantkategorier, ålder och kön. Måttet allvarlig skada används både för att följa den allmänna trafiksäkerhetsutvecklingen i Sverige och i mer specifika studier om till exempel olika trafikantgrupper. Som allvarligt skadad definieras den som i samband med en vägtrafikolycka får skador som leder till minst 1 procents permanent medicinsk invaliditet. Som komplement används också begreppet mycket allvarlig skada som definieras på motsvarande sätt men avser skador som leder till minst 10 procents permanent medicinsk invaliditet. Eftersom invaliditetsgraden inte är känd vid olyckstillfället prognosticerar man istället antal allvarligt och mycket allvarligt skadade. Grunden för prognoserna är Strada, den nationella databasen för vägtrafikolyckor i Sverige, och en metod som tagits fram av Folksam som baseras på risken att en persons skador kommer att leda till permanent medicinsk invaliditet i framtiden. Osäkerheten i prognoserna illustreras med prognosintervall. Det visade sig under arbetets gång att härledningen av prognosintervallen var relativt rättfram för fallet med en skada per person men betydligt svårare när personerna kunde ha en kombination av flera olika skador. Prognosintervallen bestämdes därför med hjälp av simulering istället för teoretiska beräkningar.
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| 34. |
- Isaeva, Leyla, et al.
(författare)
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Dynamic stabilization of cubic AuZn
- 2015
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Ingår i: Materials today: Proceedings. - : Elsevier BV. ; , s. S569-S572
-
Konferensbidrag (refereegranskat)abstract
- A recently developed temperature-dependent effective potential method is employed to study the martensitic phase transformation in AuZn. This method is based on ab initio molecular dynamics and allows to obtain finite-temperature lattice vibrational properties. We show that the transversal acoustic TA(2)[110] mode associated with the phase transition is stabilized at 300 K. Temperature evolution of single-phonon dynamic structure factor at the wave vector q= 1/3[1,1,0], associated with phonon softening and Fermi surface nesting, was also studied.
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| 35. |
- Lidestam, Björn, 1968-, et al.
(författare)
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Speed perception affected by field of view : Energy-based versus rhythm-based processing
- 2019
-
Ingår i: Transportation Research Part F. - : Elsevier. - 1369-8478 .- 1873-5517. ; 65, s. 227-241
-
Tidskriftsartikel (refereegranskat)abstract
- Two experiments were carried out to test speed perception dependency on field of view (FoV), virtual road markings (VRMs), and presentation orders. The primary purpose was to examine how the extent of the optic flow (foremost peripherally–vertically) informs the driver about egospeed. A second purpose was to examine different task demands and stimulus characteristics supporting rhythm-based versus energy-based processing. A third purpose was to examine speed changes indicative of changes in motion sensitivity. Participants were tested in a car simulator, with FoV resembling low front-door windows, and with VRMs inside the car. Three main results were found. Larger FoV, both horizontally and peripherally–vertically, significantly reduced participants' speed, as did VRMs. Delineator posts and road center lines were used for participants' rhythm-based processing, when the task was to drive at target speeds. Rich motion-flow cues presented initially resulted in lower egospeed in subsequent conditions with relatively less motion-flow cues. The practical implication is that non-iconic, naturalistic and intuitive interfaces can effectively instill spontaneous speed adaptation in drivers.
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| 36. |
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| 37. |
- Selvaraju, Ram Kumar, et al.
(författare)
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Pre-clinical evaluation of [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4 for imaging of insulinoma
- 2014
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Ingår i: Nuclear Medicine and Biology. - : Elsevier BV. - 0969-8051 .- 1872-9614. ; 41:6, s. 471-476
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Insulinoma is the most common form of pancreatic endocrine tumors responsible for hyperinsulinism in adults. These tumors overexpress glucagon like peptide-1 (GLP-1) receptor, and biologically stable GLP-1 analogs have therefore been proposed as potential imaging agents. Here, we evaluate the potential of a positron emission tomography (PET) tracer, [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4, for imaging and quantification of GLP-1 receptors (GLP-1R) in insulinoma.METHODS: [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4 was evaluated for binding to GLP-1R by in vitro autoradiography binding studies in INS-1 tumor from xenografts. In vivo biodistribution was investigated in healthy control mice, INS-1 xenografted and PANC1 xenografted immunodeficient mice at two different doses of peptide: 2.5μg/kg (baseline) and 100μg/kg (block). In vivo imaging of [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4 in xenografted mice was evaluated by small animal PET/CT using a direct comparison with the clinically established insulinoma marker [(11)C]5-hydroxy-tryptophan ([(11)C]5-HTP).RESULTS: GLP-1 receptor density could be quantified in INS-1 tumor biopsies. [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4 showed significant uptake (p≤0.05) in GLP1-R positive tissues such as INS-1 tumor, lungs and pancreas upon comparison between baseline and blocking studies. In vivo imaging showed concordant results with higher tumor-to-muscle ratio in INS-1 xenografted mice compared with [(11)C]5-HTP.CONCLUSION: [(68)Ga]Ga-DO3A-VS-Cys(40)-Exendin-4 has high affinity and specificity for GLP-1R expressed on insulinoma in vitro and in vivo.
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| 38. |
- Spreco, Armin, et al.
(författare)
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Nowcasting (Short-Term Forecasting) of COVID-19 Hospitalizations Using Syndromic Healthcare Data, Sweden, 2020
- 2022
-
Ingår i: Emerging Infectious Diseases. - : Centers for Disease Control and Prevention (CDC). - 1080-6040 .- 1080-6059. ; 28:3, s. 564-571
-
Tidskriftsartikel (refereegranskat)abstract
- We report on local nowcasting (short-term forecasting) of coronavirus disease (COVID-19) hospitalizations based on syndromic (symptom) data recorded in regular healthcare routines in Östergötland County (population ≈465,000), Sweden, early in the pandemic, when broad laboratory testing was unavailable. Daily nowcasts were supplied to the local healthcare management based on analyses of the time lag between telenursing calls with the chief complaints (cough by adult or fever by adult) and COVID-19 hospitalization. The complaint cough by adult showed satisfactory performance (Pearson correlation coefficient r>0.80; mean absolute percentage error <20%) in nowcasting the incidence of daily COVID-19 hospitalizations 14 days in advance until the incidence decreased to <1.5/100,000 population, whereas the corresponding performance for fever by adult was unsatisfactory. Our results support local nowcasting of hospitalizations on the basis of symptom data recorded in routine healthcare during the initial stage of a pandemic. © 2022 Centers for Disease Control and Prevention (CDC). All rights reserved.
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| 39. |
- Svensson, Nina, 1988-, et al.
(författare)
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Ride the future – strategisk satsning : fem studier med fokus på autonoma bussar i städer
- 2022
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fem noga utvalda förstudier har initierats av VTI som en del i den strategiska satsningen ”Ride the future” kopplad till framtidens mobilitetslösningar. Förstudiernas titel är följande: ▪ Databearbetning och visualisering av mobila luftkvalitetsmätningar. ▪ SUMO och Unreal Engine för co-simulering. ▪ Exploring spatio-temporal accessibility in Lambohov: a pre-study. ▪ Vägytans betydelse för vibrationer och komfort i långsamma fordon. ▪ Infrastrukturbehov vid busshållplatser. Föreliggande pm innehåller en kort beskrivning av studierna och den mer utförliga redovisningen återfinns i bilagan.
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| 40. |
- Timpka, Toomas, et al.
(författare)
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A neighborhood susceptibility index for planning of local physical interventions in response to pandemic influenza outbreaks
- 2010
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Ingår i: AMIA Annual Symposium Proceedings. - 1942-597X. ; 2010, s. 792-796
-
Tidskriftsartikel (refereegranskat)abstract
- The global spread of a novel A (H1N1) influenza virus in 2009 has highlighted the possibility of a devastating pandemic similar to the 'Spanish flu' of 1917-1918. Responding to such pandemics requires careful planning for the early phases where there is no availability of pandemic vaccine. We set out to compute a Neighborhood Influenza Susceptibility Index (NISI) describing the vulnerability of local communities of different geo-socio-physical structure to a pandemic influenza outbreak. We used a spatially explicit geo-physical model of Linköping municipality (pop. 136,240) in Sweden, and employed an ontology-modeling tool to define simulation models and transmission settings. We found considerable differences in NISI between neighborhoods corresponding to primary care areas with regard to early progress of the outbreak, as well as in terms of the total accumulated share of infected residents counted after the outbreak. The NISI can be used in local preparations of physical response measures during pandemics.
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| 41. |
- Timpka, Toomas, et al.
(författare)
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Age as a determinant for dissemination of seasonal and pandemic influenza : An open cohort study of influenza outbreaks in Östergötland County, Sweden
- 2012
-
Ingår i: PLOS ONE. - San Francisco : Public Library of Science. - 1932-6203. ; 7:2, s. e31746-
-
Tidskriftsartikel (refereegranskat)abstract
- An understanding of the occurrence and comparative timing of influenza infections in different age groups is important for developing community response and disease control measures. This study uses data from a Scandinavian county (population 427,000) to investigate whether age was a determinant for being diagnosed with influenza 2005–2010 and to examine if age was associated with case timing during outbreaks. Aggregated demographic data were collected from Statistics Sweden, while influenza case data were collected from a county-wide electronic health record system. A logistic regression analysis was used to explore whether case risk was associated with age and outbreak. An analysis of variance was used to explore whether day for diagnosis was also associated to age and outbreak. The clinical case data were validated against case data from microbiological laboratories during one control year. The proportion of cases from the age groups 10–19 (p<0.001) and 20–29 years old (p<0.01) were found to be larger during the A pH1N1 outbreak in 2009 than during the seasonal outbreaks. An interaction between age and outbreak was observed (p<0.001) indicating a difference in age effects between circulating virus types; this interaction persisted for seasonal outbreaks only (p<0.001). The outbreaks also differed regarding when the age groups received their diagnosis (p<0.001). A post-hoc analysis showed a tendency for the young age groups, in particular the group 10–19 year olds, led outbreaks with influenza type A H1 circulating, while A H3N2 outbreaks displayed little variations in timing. The validation analysis showed a strong correlation (r = 0.625; p<0.001) between the recorded numbers of clinically and microbiologically defined influenza cases. Our findings demonstrate the complexity of age effects underlying the emergence of local influenza outbreaks. Disentangling these effects on the causal pathways will require an integrated information infrastructure for data collection and repeated studies of well-defined communities.
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| 42. |
- Timpka, Toomas, et al.
(författare)
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Performance of eHealth data sources in local influenza surveillance : a 5-year open cohort study
- 2014
-
Ingår i: Journal of Medical Internet Research. - : JMIR Publications Inc.. - 1438-8871. ; 16:4, s. 216-225
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: There is abundant global interest in using syndromic data from population-wide health information systems-referred to as eHealth resources-to improve infectious disease surveillance. Recently, the necessity for these systems to achieve two potentially conflicting requirements has been emphasized. First, they must be evidence-based; second, they must be adjusted for the diversity of populations, lifestyles, and environments.OBJECTIVE: The primary objective was to examine correlations between data from Google Flu Trends (GFT), computer-supported telenursing centers, health service websites, and influenza case rates during seasonal and pandemic influenza outbreaks. The secondary objective was to investigate associations between eHealth data, media coverage, and the interaction between circulating influenza strain(s) and the age-related population immunity.METHODS: An open cohort design was used for a five-year study in a Swedish county (population 427,000). Syndromic eHealth data were collected from GFT, telenursing call centers, and local health service website visits at page level. Data on mass media coverage of influenza was collected from the major regional newspaper. The performance of eHealth data in surveillance was measured by correlation effect size and time lag to clinically diagnosed influenza cases.RESULTS: Local media coverage data and influenza case rates showed correlations with large effect sizes only for the influenza A (A) pH1N1 outbreak in 2009 (r=.74, 95% CI .42-.90; P<.001) and the severe seasonal A H3N2 outbreak in 2011-2012 (r=.79, 95% CI .42-.93; P=.001), with media coverage preceding case rates with one week. Correlations between GFT and influenza case data showed large effect sizes for all outbreaks, the largest being the seasonal A H3N2 outbreak in 2008-2009 (r=.96, 95% CI .88-.99; P<.001). The preceding time lag decreased from two weeks during the first outbreaks to one week from the 2009 A pH1N1 pandemic. Telenursing data and influenza case data showed correlations with large effect sizes for all outbreaks after the seasonal B and A H1 outbreak in 2007-2008, with a time lag decreasing from two weeks for the seasonal A H3N2 outbreak in 2008-2009 (r=.95, 95% CI .82-.98; P<.001) to none for the A p H1N1 outbreak in 2009 (r=.84, 95% CI .62-.94; P<.001). Large effect sizes were also observed between website visits and influenza case data.CONCLUSIONS: Correlations between the eHealth data and influenza case rates in a Swedish county showed large effect sizes throughout a five-year period, while the time lag between signals in eHealth data and influenza rates changed. Further research is needed on analytic methods for adjusting eHealth surveillance systems to shifts in media coverage and to variations in age-group related immunity between virus strains. The results can be used to inform the development of alert-generating eHealth surveillance systems that can be subject for prospective evaluations in routine public health practice.
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| 43. |
- Timpka, Toomas, et al.
(författare)
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Predictive performance of telenursing complaints in influenza surveillance: a prospective cohort study in Sweden
- 2014
-
Ingår i: Eurosurveillance. - : EUR CENTRE DIS PREVENTION and CONTROL. - 1025-496X .- 1560-7917. ; 19:46, s. 24-32
-
Tidskriftsartikel (refereegranskat)abstract
- Syndromic data sources have been sought to improve the timely detection of increased influenza transmission. This study set out to examine the prospective performance of telenursing chief complaints in predicting influenza activity. Data from two influenza seasons (2007/08 and 2008/09) were collected in a Swedish county (population 427,000) to retrospectively determine which grouping of telenursing chief complaints had the largest correlation with influenza case rates. This grouping was prospectively evaluated in the three subsequent seasons. The best performing telenursing complaint grouping in the retrospective algorithm calibration was fever (child, adult) and syncope (r=0.66; pless than0.001). In the prospective evaluation, the performance of 14-day predictions was acceptable for the part of the evaluation period including the 2009 influenza pandemic (area under the curve (AUC)=0.84; positive predictive value (PPV)=0.58), while it was strong (AUC=0.89; PPV=0.93) for the remaining evaluation period including only influenza winter seasons. We recommend the use of telenursing complaints for predicting winter influenza seasons. The method requires adjustments when used during pandemics.
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| 44. |
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| 45. |
- Timpka, Toomas, et al.
(författare)
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Requirements and Design of the PROSPER Protocol for Implementation of Information Infrastructures Supporting Pandemic Response: A Nominal Group Study
- 2011
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:3, s. 0017941-
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Advanced technical systems and analytic methods promise to provide policy makers with information to help them recognize the consequences of alternative courses of action during pandemics. Evaluations still show that response programs are insufficiently supported by information systems. This paper sets out to derive a protocol for implementation of integrated information infrastructures supporting regional and local pandemic response programs at the stage(s) when the outbreak no longer can be contained at its source. Methods: Nominal group methods for reaching consensus on complex problems were used to transform requirements data obtained from international experts into an implementation protocol. The analysis was performed in a cyclical process in which the experts first individually provided input to working documents and then discussed them in conferences calls. Argument-based representation in design patterns was used to define the protocol at technical, system, and pandemic evidence levels. Results: The Protocol for a Standardized information infrastructure for Pandemic and Emerging infectious disease Response (PROSPER) outlines the implementation of information infrastructure aligned with pandemic response programs. The protocol covers analyses of the community at risk, the response processes, and response impacts. For each of these, the protocol outlines the implementation of a supporting information infrastructure in hierarchical patterns ranging from technical components and system functions to pandemic evidence production. Conclusions: The PROSPER protocol provides guidelines for implementation of an information infrastructure for pandemic response programs both in settings where sophisticated health information systems already are used and in developing communities where there is limited access to financial and technical resources. The protocol is based on a generic health service model and its functions are adjusted for community-level analyses of outbreak detection and progress, and response program effectiveness. Scientifically grounded reporting principles need to be established for interpretation of information derived from outbreak detection algorithms and predictive modeling.
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| 46. |
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| 47. |
- Wegrzyniak, Olivia, et al.
(författare)
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Imaging of fibrogenesis in the liver by [18F]TZ-Z0959 : an Affibody molecule targeting platelet derived growth factor receptor β
- 2023
-
Ingår i: EJNMMI Radiopharmacy and Chemistry. - : Springer Nature. - 2365-421X. ; 8:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Platelet-derived growth factor receptor beta (PDGFRβ) is a receptor overexpressed on activated hepatic stellate cells (aHSCs). Positron emission tomography (PET) imaging of PDGFRβ could potentially allow the quantification of fibrogenesis in fibrotic livers. This study aims to evaluate a fluorine-18 radiolabeled Affibody molecule ([18F]TZ-Z09591) as a PET tracer for imaging liver fibrogenesis. Results: In vitro specificity studies demonstrated that the trans-Cyclooctenes (TCO) conjugated Z09591 Affibody molecule had a picomolar affinity for human PDGFRβ. Biodistribution performed on healthy rats showed rapid clearance of [18F]TZ-Z09591 through the kidneys and low liver background uptake. Autoradiography (ARG) studies on fibrotic livers from mice or humans correlated with histopathology results. Ex vivo biodistribution and ARG revealed that [18F]TZ-Z09591 binding in the liver was increased in fibrotic livers (p = 0.02) and corresponded to binding in fibrotic scars. Conclusions: Our study highlights [18F]TZ-Z09591 as a specific tracer for fibrogenic cells in the fibrotic liver, thus offering the potential to assess fibrogenesis clearly. Graphical abstract: [Figure not available: see fulltext.]
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| 48. |
- Aasa, Anna, et al.
(författare)
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Collecting dialect data and making use of them an interim report from Swedia 2000
- 2000
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Ingår i: Proceedings FONETIK 2000. ; , s. 17-20
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper consists of two, somewhat disparate parts. In the first part, some experiences of two years of fieldwork are summarized, concentrating, as the subtitle suggests, on the very heart of phonetic fieldwork: the encounters and interviews with the informants. As a result of the fieldwork, the project now has access to recordings from approximately 1300 speakers of more than 100 dialects of Swedish. We are currently initiating research on various aspects of the sound patterns of these dialects. The second part of the paper is meant to give an overview of some of our research plans for the near future.
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| 49. |
- Aasa, Anna, et al.
(författare)
-
Vowel quantity in West Swedish - the villain of the piece?
- 2000
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Ingår i: Proceedings of the Swedish Phonetics Conference FONETIK 2000.. ; , s. 17-20
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper consists of two, somewhat disparate parts. In the first part, some experiences of two years of fieldwork are summarized, concentrating, as the subtitle suggests, on the very heart of phonetic fieldwork: the encounters and interviews with the informants. As a result of the fieldwork, the project now has access to recordings from approximately 1300 speakers of more than 100 dialects of Swedish. We are currently initiating research on various aspects of the sound patterns of these dialects. The second part of the paper is meant to give an overview of some of our research plans for the near future.
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| 50. |
- Abdel-Hafiez, Mahmoud, et al.
(författare)
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From Insulator to Superconductor : A Series of Pressure-Driven Transitions in Quasi-One-Dimensional TiS3 Nanoribbons
- 2024
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 24:18, s. 5562-5569
-
Tidskriftsartikel (refereegranskat)abstract
- Transition metal trichalcogenides (TMTCs) offer remarkable opportunities for tuning electronic states through modifications in chemical composition, temperature, and pressure. Despite considerable interest in TMTCs, there remain significant knowledge gaps concerning the evolution of their electronic properties under compression. In this study, we employ experimental and theoretical approaches to comprehensively explore the high-pressure behavior of the electronic properties of TiS3, a quasi-one-dimensional (Q1D) semiconductor, across various temperature ranges. Through high-pressure electrical resistance and magnetic measurements at elevated pressures, we uncover a distinctive sequence of phase transitions within TiS3, encompassing a transformation from an insulating state at ambient pressure to the emergence of an incipient superconducting state above 70 GPa. Our findings provide compelling evidence that superconductivity at low temperatures of ∼2.9 K is a fundamental characteristic of TiS3, shedding new light on the intriguing high-pressure electronic properties of TiS3 and underscoring the broader implications of our discoveries for TMTCs in general.
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