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  • 147401.
    Ullman, Gustaf
    et al.
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiofysik.
    Sandborg, Michael
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiofysik. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Dance, D
    Hunt, R
    Alm-Carlsson, Gudrun
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiofysik. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    The influence of patient thickness and imaging system on patient dose and physical image quality in digital chest imaging2005Inngår i: Radiation Protection Dosimetry, ISSN 0144-8420, E-ISSN 1742-3406, Vol. 114, nr 1-3, s. 294-297Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this work was to study the influence of patient thickness, tube voltage and image detector on patient dose, contrast and ideal observer signal-to-noise ratio (SNRI), for pathological details positioned at different regions in the image in posterior-anterior (PA) chest radiology. A Monte Carlo computational model was used to compute measures of physical image quality (contrast, SNRI) and patient effective dose, E. Two metastasis-like details positioned in the central right lung and right lung near the spine, respectively, were studied. The tube voltage was varied between 100 and 150 kV and the patient thickness between 20 and 28 cm. Both, a computed radiography (CR) system and a direct radiography (DR) system, were investigated. The DR system provides both lower doses and better image quality compared with the CR system. The SNRI2/E is ∼2.9 times higher for the DR system compared with the CR system. © The Author 2005. Published by Oxford University Press. All rights reserved.

  • 147402.
    Ullman, Gustaf
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Dance, David R.
    Joint Department of Physics, The Royal Marsden NHS Foundation Trust and Institute of Cancer Research, London, UK.
    Hunt, Roger A.
    Joint Department of Physics, The Royal Marsden NHS Foundation Trust and Institute of Cancer Research, London, UK.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Towards optimization in digital chest radiography using Monte Carlo modelling2006Inngår i: Physics in medicine and biology, ISSN 0031-9155, Vol. 51, nr 11, s. 2729-2743Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A Monte Carlo based computer model of the x-ray imaging system was used to investigate how various image quality parameters of interest in chest PA radiography and the effective dose E vary with tube voltage (90–150 kV), additional copper filtration (0–0.5 mm), anti-scatter method (grid ratios 8–16 and air gap lengths 20–40 cm) and patient thickness (20–28 cm) in a computed radiography (CR) system. Calculated quantities were normalized to a fixed value of air kerma (5.0 µGy) at the automatic exposure control chambers. Soft-tissue nodules were positioned at different locations in the anatomy and calcifications in the apical region. The signal-to-noise ratio, SNR, of the nodules and the nodule contrast relative to the contrast of bone (C/CB) as well as relative to the dynamic range in the image (Crel) were used as image quality measures. In all anatomical regions, except in the densest regions in the thickest patients, the air gap technique provides higher SNR and contrast ratios than the grid technique and at a lower effective dose E. Choice of tube voltage depends on whether quantum noise (SNR) or the contrast ratios are most relevant for the diagnostic task. SNR increases with decreasing tube voltage while C/CB increases with increasing tube voltage.

  • 147403.
    Ullman, Gustaf
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Dance, David R.
    Joint Department of Physics, The Royal Marsden NHS Trust, London, UK .
    Hunt, Roger
    Joint Department of Physics, The Royal Marsden NHS Trust, London, UK .
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Distributions of scatter to primary ratios and signal to noise ratios per pixel in digital chest imaging2005Inngår i: Radiation protection dosimetry, ISSN 0144-8420, Vol. 114, nr 1-3, s. 355-358Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this work was to calculate distributions of scatter-to-primary ratios (s/p) and signal-to-noise ratios per pixel (SNRp) in chest images. Such distributions may provide useful information on how physical image quality (contrast, SNR) is distributed over the posterior/anterior (PA) chest image. A Monte Carlo computer program was used for the calculations, including a model of both the patient (voxel phantom) and the imaging system (X-ray tube, anti-scatter grid and image detector). The calculations were performed for three PA thicknesses 20, 24 and 28 cm. For a 24 cm patient, the s/p varies between 0.5 in the lung to 2.5 behind the spine and heart. The corresponding variation of the SNRp is a factor of 3, with the highest values in the lung. Increasing the patient thickness from 20 to 28 cm increases the s/p by a factor of 2.2 behind the spine and heart.

  • 147404.
    Ullman, Gustaf
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Dance, David R.
    Joint Department of Physics, The Royal Marsden NHS Trust, London, UK.
    Yaffe, Martin
    Department of Medical Biophysics, University of Toronto, Sunnybrook and Women's College Health Sciences Centre, Ontario, Canada.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    A search for optimal x‐ray spectra in iodine contrast media mammography2005Inngår i: Physics in medicine and biology, ISSN 0031-9155, Vol. 50, nr 13, s. 3143-3152Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this work was to search for the optimal x-ray tube voltage and anode–filter combination in digital iodine contrast media mammography. In the optimization, two entities were of interest: the average glandular dose, AGD, and the signal-to-noise ratio, SNR, for detection of diluted iodine contrast medium. The optimum is defined as the technique maximizing the figure of merit, SNR2/AGD. A Monte Carlo computer program was used which simulates the transport of photons from the x-ray tube through the compression plate, breast, breast support plate, anti-scatter grid and image detector. It computes the AGD and the SNR of an iodine detail inside the compressed breast. The breast thickness was varied between 2 and 8 cm with 10–90% glandularity. The tube voltage was varied between 20 and 55 kV for each anode material (Rh, Mo and W) in combination with either 25 µm Rh or 0.05–0.5 mm Cu added filtration. The x-ray spectra were calculated with MCNP4C (Monte Carlo N-Particle Transport Code System, version 4C). A CsI scintillator was used as the image detector. The results for Rh/0.3mmCu, Mo/0.3mmCu and W/0.3mmCu were similar. For all breast thicknesses, a maximum in the figure of merit was found at approximately 45 kV for the Rh/Cu, Mo/Cu and W/Cu combinations. The corresponding results for the Rh/Rh combination gave a figure of merit that was typically lower and more slowly varying with tube voltage. For a 4 cm breast at 45 kV, the SNR2/AGD was 3.5 times higher for the Rh/0.3mmCu combination compared with the Rh/Rh combination. The difference is even larger for thicker breasts. The SNR2/AGD increases slowly with increasing Cu-filter thickness. We conclude that tube voltages between 41 and 55 kV and added Cu-filtration will result in significant dose advantage in digital iodine contrast media mammography compared to using the Rh/Rh anode/filter combination at 25–32 kV.

  • 147405.
    Ullman, Gustav
    et al.
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Validation of Voxman Monte Carlo code and calibration for digital systems2003Rapport (Annet vitenskapelig)
    Abstract [en]

    The objective of this work was to test the Monte Carlo model ‘Voxman’ against measurements on x-ray systems in the clinic. X-ray transmission experiments are performed to test of the accuracy of the Monte Carlo photon transport. Experiments were also performed with an image plate (CR) system in the clinic to compare the measured pixel values with calculated pixel values. Measurements were also performed with the automatic exposure control (AEC) chambers used in Linköping and Motala. The purpose for those measurements was to choose a normalisation of the entrance surface dose.

  • 147406.
    Ullman, Gustav
    et al.
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Dance, David R
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Båth, M.
    Department of Radiation Physics, Göteborg, Sweden.
    Håkansson, M.
    Department of Radiation Physics, Göteborg, Sweden.
    Börjesson, S.
    Department of Radiation Physics, Göteborg, Sweden.
    Hunt, Roger
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    On the extent of quantum noise limitation in digital chest radiography2004Rapport (Annet vitenskapelig)
    Abstract [en]

    The aim for this work was to study to what extent the detection of nodules is quantum noise limited, based on the combined results from a nodule-detection clinical trial and a Monte Carlo computational model of a digital chest imaging system. The Monte Carlo computer program computes measures of physical image quality such as image contrast, C and signalto-noise ratio, SNR for nodules of any size. A computed radiography (CR) imaging system used simulated. The patient anterior-posterior thickness was 25 cm and nodules with diameters between 1-40 mm were included. The image contrast and SNR was calculated for 1600 (40x40) positions in the chest image and averaged over five anatomical regions of interest (lateral pulmonary, retrocardial, hilar, lower- and upper mediastinal regions). Threshold contrasts for each region, Cth, corresponding to Az=0.80 for detecting a 10 mm nodule, were deduced from the clinical trial. A threshold is also used for the quantum noise signal-to-noise ratio, SNRth. The model computes the diameter of a disk-shaped object that is required to comply with the two criteria: SNR≥SNRth and C≥Cth. A system is said to be quantum noise limited when the nodule size required to fulfil both criteria is not limited by the contrast but by the SNR. The required nodule diameter is largest in the hilar region (25 mm) and smallest in the lateral pulmonary region (11 mm). When the threshold SNRth=25 is used, the lower mediastinal region is quantum noise limited already at low speed classes (S>100). The hilar region is never quantum noise limited at realistic speed classes (S<1000). The accuracy of this model will be tested in the future by more sophisticated modelling of anatomical background and noise in the SNR-expression.

  • 147407.
    Ullman, Gustav
    et al.
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Dance, David R
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Hunt, Roger
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Distributions of scatter-to-primary ratios in chest PA radiography using grid or air gap for scatter-rejection2004Rapport (Annet vitenskapelig)
    Abstract [en]

    The aim for this work was to calculate distributions of scatter-to-primary ratios (εs/εp) and signal-to-noise ratios per pixel (SNRp) for a large set of imaging systems with either grid or air gap for scatter rejection. Grids with ratio 8-16 and air gap length 20 and 40 cm were used. The tube voltage was varied between 90-150 kV and three patient thickness between 20-28 cm were tested in order to compare scatter-rejections techniques for different conditions. Distributions of this sort may provide useful information on how physical image quality (contrast, SNR) is distributed over the chest PA image. A Monte Carlo computer program was used for the calculations, including a model of both the patient (voxel phantom) and the imaging system. The mean value of the εs/εp is 0.39 in the hilar region and 1.72 in the lower mediastinal region. For a 28 cm patient, the corresponding values are 0.42 in the hilar region and 2.58 in the lower mediastinal region. The grid with ratio 16 is the most efficient scatter rejection technique in all regions except the hilar region. In the hilar region, the most efficient technique is the 40 cm air gap.

  • 147408.
    Ullman, Gustav
    et al.
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Dance, David R
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Hunt, Roger
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Optimisation of chest radiology by computer modelling of image quality measures and patient effective dose2004Rapport (Annet vitenskapelig)
    Abstract [en]

    A set of modelled computed radiography (CR) systems are compared with a reference system. Calculations are performed, which compares the effective dose and a set of figures of merit corresponding to the image quality of both the modelled systems and the reference system. For a nodule with soft tissue corresponding, the signal-to-noise ratio, SNR, is found to decrease with increasing tube voltage. On the other hand, the ratio of the contrast of the nodule compared to the contrast of a rib (nodule-to-rib contrast-ratio) is found to increase with increasing tube voltage.

  • 147409.
    Ullman, Gustav
    et al.
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Hunt, Roger
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Dance, David R
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Implementation of pathologies in the Monte Carlo model in chest and breast imaging2003Rapport (Annet vitenskapelig)
    Abstract [en]

    The Monte Carlo simulation model of the chest and breast imaging systems including a voxelised model of the patient are used to compute measures of image quality and patient absorbed dose. It is important that the model computes measures of image quality of pathological details that are similar in size, composition and position as real pathological details in typical chest and breast images. Moreover, the other partners of the co-coordinated research project will produce hybrid images with pathological details and have these images assessed by a group of radiologist. The model will then be used to study to what extent variations in clinical image quality can be explained by variations in physical image quality, for example signal-to-noise ratio. This report summarizes the selection of pathological details to include in the model of chest and breast imaging systems.

  • 147410.
    Ullman, Gustav
    et al.
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet.
    Sandborg, Michael
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Tingberg, Anders
    Department of Radiation Physics, Malmö University Hospital, Sweden.
    Dance, David R
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Hunt, Roger
    Department of Physics, The Royal Marsden NHS Trust, UK.
    Alm Carlsson, Gudrun
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Comparison of clinical and physical measures of image quality in chest PA and pelvis AP views at varying tube voltages2004Rapport (Annet vitenskapelig)
    Abstract [en]

    Image quality in digital chest PA and pelvis AP was assessed using two different methods; one based on observations of images of an anthropomorphic phantom, one based on computer modelling using an anthropomorphic voxel phantom. The tube voltage was varied within a broad range (50-150 kV), including those values typically used with screen-film radiography. The tube charge was altered so that approximately the same effective dose was achieved in the modelled patient (anthropomorphic phantom). Two x-ray units were employed using a digital image detector (computed radiography, CR, system) with standard tube filtration and anti-scatter device. Clinical image quality was assessed by a group of radiologists using a visual grading analysis (VGA) technique based on the revised CEC image criteria. Physical image quality was derived from the computer model in terms of the signal-to-noise ratio, SNR for fixed effective dose in the voxel phantom. The computer model uses Monte Carlo simulations of the patient and complete imaging system. Both the VGAS (visual grading analysis score) and SNR increase with decreasing tube voltage in both chest PA and pelvis AP examinations, indicating superior performance if lower tube voltages than used today are employed in digital radiology. A positive correlation between clinical and physical measures of image quality was found. The pros and cons of using lower tube voltages with CR digital radiography than typically used in analogue screen-film radiography are discussed as well as the relevance of using VGAS and quantum noise SNR as measures of image quality.

  • 147411. Ullman, Johan
    et al.
    Kangas, Nils
    Ullman, Pia
    Wartenberg, Fredrik
    Ericson, Mats
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekonomi och organisation (Inst.), Industriell ekonomi och organisation (Avd.) (stängd 20130101).
    A new approach to the mouse arm syndrome.2003Inngår i: International Journal of Occupational Safety and Ergonomics, ISSN 1080-3548, E-ISSN 2376-9130, Vol. 9, nr 4, s. 463-477Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    OBJECTIVES: The study validates a new computer mouse concept. The tested device is a small mouse with a pivoting pen-shaped handle. The hypothesis behind the design is the assumptions that the pen grip requires less static tension than the normal mouse grip and that fine-motor, high precision tasks normally are done with finger movements with forearm at rest.

    METHODS: Four muscles were monitored with electromyography (EMG) during work with a new mouse and with a traditional mouse.

    RESULTS: EMG activity was significant lower, in M. pronator teres--46%, M. extensor digitorum--46%, M. trapezius--69%, and M. levator scapulae--82%, during work with the new mouse as compared to the traditional mouse.

    CONCLUSION: Altering the design of the computer mouse can significantly reduce muscular tension.

  • 147412.
    Ullmark, Gösta
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Femoral head fractures: hemiarthroplasty or total hip arthroplasty?2014Inngår i: HIP International, ISSN 1120-7000, E-ISSN 1724-6067, Vol. 24, nr S10, s. S12-S14Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Most femoral neck fractures are osteoporotic fractures in the elderly. The one-year mortality after neck fracture in this group is 24%. For hemiarthroplasty (HA) the bipolar heads have a risk reduction for reoperation due to acetabular erosion compared with monoblock heads. Surprisingly, the bipolar head had an increased reoperation risk for dislocation, infection and for periprosthetic fracture. Total hip arthroplasty (THA) after fracture has a four-fold raised risk for dislocation compared with THA after osteoarthritis. A larger head on the same neck (head to neck ratio) results in a theoretically larger range of movement and hence less risk for dislocation. The dual mobility bearing has, theoretically, the largest range of movement and good clinical results. Functional results are better for THA compared with HA. Arthroplasty for fracture has much better results compared with arthroplasty after a failed internal fixation; the risk for reoperation is more than doubled for the latter. A Swedish hip arthroplasty register study found a 20-fold higher risk for periprosthetic fracture when comparing uncemented HA with matt cemented HA. Also a polished cemented stem had 131/2-fold higher risks compared with a matt. The mortality during the first day after surgery is higher for cemented compared with uncemented arthroplasties, but lower after one week, one month and one year. Analysing the time points together resulted in no difference. A matt cemented THA with a maximum head size, maybe dual mobility, has the best results, and is also for the low-demanding elderly.

  • 147413.
    Ullmark, Gösta
    Uppsala universitet, Medicinska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper.
    Morcelised Impacted Cortico-Cancellous Bone Allografts in Revision Surgery for Endoprosthetic Loosening with Osteolysis2001Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Revision total hip arthroplasty (RTHA) and filling of the bone defects with impacted particulated bone allograft is the concept that has been studied in this thesis.

    In three in vitro models, biomechanical aspects of morcelised and impacted bone allografts were studied. The recoil of an impacted graft bed (as the impaction device was released) was found to be substantial (11-34 %). The clinical implication of this is that the space for a cement mantle may disappear. The recoil was higher using smaller bone chips and using higher compaction pressure. Higher initial impaction energy was found to create a more stable graft bed, which also was the case for larger bone chips. The rotational stability for a cup cemented on an impacted graft bed was doubled when using larger chips compared to smaller. When the larger chips were defatted, the stability was doubled again.

    Clinical and radiological results after revision total hip arthroplasty using impaction grafting was studied for Charnley and Lubinus prosthesis after a mean follow-up 64 months. The clinical results were good for both groups. Minor subsidence of the femoral stem occurred in a few RTHA in both groups. Mechanical failure was four per cent in both groups.

    A surgical method for revision total knee arthroplasty with impaction grafting was demonstrated. The clinical and radiological medium term results were good.

    Morphological outcome in biopsies was studied from 20 patients with impaction bone grafting. One month after RTHA a fibrous stroma and some newly formed trabecular bone was found. In-growth of living bone was almost complete after 48 months.

    Positron Emission Tomography (PET) was used to evaluate the metabolic events taking place after impaction bone grafting. Already eight days after surgery there was a high activity inside the graft beds indicating neovascularisation and active calcium metabolism. After one year this activity had diminished.

  • 147414.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Kärrholm, Johan
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Bone metabolism analyzed by PET and DXA following revision THA using a distally fixed stem: A pilot study2011Inngår i: HIP International, ISSN 1120-7000, E-ISSN 1724-6067, Vol. 21, nr 1, s. 30-38Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a pilot study we analyzed bone remodeling using F-18-PET (positon emission tomography) scanning or DXA (dual-energy x-ray absorptiometry) in 3 patient groups, one with a loose femoral stem and 2 after revision using a modular stem (MP). In loose implants (group 1), bone formation activity compared to the contralateral healthy femur was 261 %. In the proximal part of the femur bone formation was increased by 253 % one week after revision (group 2) and did not normalize within 1 year. In the distal region it decreased to normal after one year. In the second revision group DXA showed decreased bone mineral density at 6 and 24 months (group 3). The PET technique provided evidence of bone healing despite osteolysis and prosthetic loosening which continued after revision. Decreasing BMD after revision in the third group is multifactorial, but suggests that despite intensive bone formation resorption was still higher.

  • 147415.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Nilsson, Olle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Maripuu, Enn
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Radiologi.
    Analysis of bone mineralization on uncemented femoral stems by [18F]-fluoride-PET2013Inngår i: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 84, nr 2, s. 138-144Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose We present the first study using fluoride-positron emission CT (F-PET/CT) to analyze mineralization of bone in the femur adjacent to uncemented stems following total hip arthroplasty (THA). We studied patients who were operated bilaterally for osteoarthritis with 2 different stems during the same surgical session. Patients and methods THA was performed bilaterally during the same surgical session in 8 patients with bilateral osteoarthritis of the hip. An SL-PLUS stem was inserted in one hip and a Beta Cone stem was inserted in the contralateral hip, with randomization of side and sequence. A second group of 12 individuals with a normal healthy hip was used as reference for normal bone metabolism. Clinical and radiographic evaluation was performed preoperatively, postoperatively, and at 2 years. We used [18F]-fluoride-PET/CT to analyze bone mineralization adjacent to the stems 1 week, 4 months, and 12 months after surgery. We modified the Polar Map system to fit the upper femur for analysis and presentation of the PET results from 12 regions of interest adjacent to the whole stem. Results The clinical results were good at 2 years. By radiography, all stems were stable. At PET analyses 1 week after surgery, the activity was higher for the SL-PLUS group than for the BetaCone group. The activity was statistically significantly higher for both stems than the reference values at 4 months, and was most pronounced in the upper femur. At one year, the activity had declined more for the BC group than for the SL group. Interpretation The bone mineralization activity varied between different regions for the same stem and between different time periods for each group. F-PET/CT is a novel and valuable tool for analysis of bone mineralization patterns around uncemented femoral stems in detail. The combination of PET/CT analysis and the modified Polar Map system may provide a useful tool for future studies of metabolic bone responses to prosthetic implants.

  • 147416.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Obrant, KJ
    Histology of impacted bone-graft incorporation2002Inngår i: The Journal of Arthroplasty, ISSN 0883-5403, E-ISSN 1532-8406, Vol. 17, nr 2, s. 150-157Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We describe the histologic findings of 31 tissue samples from 21 cases in 19 different patients taken 1 to 48 months after revision arthroplasty and impaction grafting in the hip (Lubinus SP-II prosthesis Waldemar Link, Hamburg, Germany, or Charnley Elite prosthesis, Johnson & Johnson, New Brunswick, NJ) and the knee (Link Rotation Knee Waldemar Link). One month after surgery, a fibrous stroma and some newly formed woven bone were found in the graft bed. After 4 months, many of the dead trabeculae in the graft bed had layers of living bone and osteoid in all samples. These layers, indicating a gradual ingrowth of living bone, increased over time. In the proximal end of the femur examined after 48 months, a significant proportion of the graft bone remained dead, whereas in the rest of the femur, the bone healing was complete. A similar but possibly less frequent bone formation was found in the 2 cases evaluated after a revision total knee arthroplasty combined with impaction grafting.

  • 147417.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Sundgren, Kent
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Milbrink, Jan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Nilsson, Olle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Klinisk fysiologi.
    Femoral head viability following resurfacing arthroplasty: A clinical positron emission tomography study2011Inngår i: HIP International, ISSN 1120-7000, E-ISSN 1724-6067, Vol. 21, nr 1, s. 66-70Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hip resurfacing (HR) carries attendant risks of avascular necrosis (AVN) and femoral neck fracture. We used fluoride positor emission tomography (PET) scans to analyze bone metabolism 2-5 years after surgery in 35 cases. Three of the patients had been clinical failures. Using PET scans in the remaining 32 cases, 7 were found to have an area of non-viable bone in the femoral head. This was seen following both posterior and antero lateral approaches. Fluoride PET is a sensitive and useful method for evaluating bone metabolism following HR.

  • 147418.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Sundgren, Kent
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Milbrink, Jan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Nilsson, Olle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Metabolic development of necrotic bone in the femoral head following resurfacing arthroplasty: A clinical [(18)F]fluoride-PET study in 11 asymptomatic hips2012Inngår i: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 83, nr 1, s. 22-25Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background and purpose

    One concern regarding resurfacing arthroplasty is the viability of the diminished femoral head and the postoperative risk of collapse, or a femoral neck fracture. (18)F-fluoride positron emission tomography (F-PET) enables us to assess bone viability despite there being a covering metal component. By F-PET studies, we recently showed the absence of metabolism in the remaining part of femoral heads, 1-4 years after surgery in 11 of 46 consecutive cases. We now present the further development of bone metabolism in these 11 cases.

    Patients and methods

    10 patients (11 chips) with previously shown loss of femoral head metabolism were evaluated by radiography and repeated F-PET scans, 3-6.5 years after surgery. The size of the area with low (18)F-fluoride PET uptake in the femoral head was compared to that in earlier PET images.

    Results

    No patients had any clinical symptoms; nor was any necrotic bone area visible in plain radiographs. On F-PET scans, 2 patients showed a diminished area with low uptake, 4 were unchanged, and 5 had enlarged areas.

    Interpretation

    Bone metabolism surrounding a volume of bone with no metabolic activity changes dynamically even 5 years after surgery. The presence of bone with minor uptake of F-tracer, indicating low or no bone metabolism, with further progression in 5 of 11 cases leads us to conclude that resurfacing THA should be used restrictively.

  • 147419.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Sundgren, Kent
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Milbrink, Jan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Nilsson, Olle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Osteonecrosis following resurfacing arthroplasty: A clinical positron emission tomography study of 14 cases2009Inngår i: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 80, nr 6, s. 670-674Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND AND PURPOSE: One of the main concerns regarding resurfacing arthroplasty is the viability of the remaining part of the femoral head, and the postoperative risk of a femoral neck fracture or collapse. In contrast to radiographic methods, positron emission tomography using the radiotracer [18F]-fluoride (Fluoride-PET) enables us to visualize the viability of bone in the remaining part of the head, despite the presence of the covering metal component. PATIENTS AND METHODS: This is preliminary prospective study of 14 patients who underwent an ASR resurfacing arthroplasty. Apart from clinical and radiographic analyses, all patients were analyzed by PET scan 1 week, 4 months, and 1 year after surgery. RESULTS: 1 patient had a minor region of osteonecrosis on PET scan at 1 week and at 4 months. After 1 year, the necrosis had increased to include most of the head. 2 other patients, normal at 4 months, had developed equally large osteonecrosis at 1 year. A fourth patient had a minor osteonecrosis at 1 year. None of the patients had clinical symptoms, and the necrotic areas were not visible on plain radiographs. CONCLUSIONS: We found Fluoride PET to be a sensitive and useful method for evaluation of bone metabolism at resurfacing arthroplasty. 3 of the 14 patients had developed osteonecrosis, involving most of the head at 1 year. The late onset of the phenomenon does not support the hypothesis of surgically damaged vascularity. The presence of this complication together with the lack of visibility on plain radiographs gives reason for concern.

  • 147420.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Långström, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    Nilsson, Olle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper.
    Bone regeneration 6 years after impaction bone grafting: A PET analysis2007Inngår i: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 78, nr 2, s. 201-205Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Impacted morselized bone allograft in revision total hip arthroplasty for prosthetic loosening has gained widespread clinical use during the last decades. The clinical results are good but little is known about the bone regeneration in the graft. PATIENTS AND METHODS: 5 patients were revised with impaction of morselized frozen allograft and a cemented total hip arthroplasty (THA) due to loosening and osteolysis of a primary THA. We used positron emission tomography ([18F]-fluoride PET) to produce quantitative images of new bone formation in the allograft surrounding the femur stem 6 years after surgery. RESULTS: The 5 patients had previously been analyzed by [18F]-fluoride PET during the first year after surgery (Sörensen et al. 2003). During the first year, bone formation proceeded through the graft layer and reached the cement layer surrounding the femoral stems. The clinical and radiographic results were excellent at 6 years. PET analyses at 6 years showed that the bone metabolism was significantly reduced in most areas of the proximal femur, compared to the elevated activity during the first year after surgery, and also normalized compared to the contralateral healthy femur. Graft bone metabolism distal to the stem tip remained slightly increased. Small patchy areas of increased uptake remained along the proximal femoral stem, probably reflecting small volumes of fibrous healing. INTERPRETATION: The metabolism of the allografted bone had normalized compared to native bone, indicating full regeneration throughout the graft--and a good long-term prognosis for implant fixation.

  • 147421. Ullmark, Gösta
    et al.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Nilsson, Olle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Analysis of bone formation on porous and calcium phosphate-coated acetabular cups: a randomised clinical [18F]fluoride PET study2012Inngår i: HIP International, ISSN 1120-7000, E-ISSN 1724-6067, Vol. 22, nr 2, s. 172-178Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a study using Fluoride-Positron Emission Tomography (F-PET/CT) to analyse new bone formation in periacetabular bone adjacent to press fit cups following THA. In 16 THA (8 patients) with bilateral hip osteoarthritis simultaneous bilateral total hip arthroplasty (THA) was performed, employing electrochemically applied calcium phosphate coated (HA) cups or porous-coated (PC) cups allocated at random to compare the two sides. A reference group of 13 individuals with a normal healthy hip was used to determine 'normal' bone metabolism. [18F]fluoride -PET/CT was used to analyze bone formation adjacent to the cups 1 week, 4 months and 12 months after surgery. Clinical and radiographic evaluation was performed preoperatively, postoperatively and at 2 years. Bone forming activity had a mean of 5.71, 4.69 and 3.47 SUV around the HA- and 5.04, 4.80 and 3.50 SUV around the PC-cups at 1 week, 4 months and 12 months respectively. Normal bone metabolism was 3.68 SUV. After 1 year activity had declined to normal levels for both groups. The clinical results were good in all cases. HA coating resulted in higher uptake indicating higher bone forming activity after 1 week. F-PET/CT is a valuable tool to analyse bone formation and secondary stabilisation of an acetabular cup.

  • 147422.
    Ullmark, Gösta
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Gävleborg.
    Sörensen, Jens
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för radiologi, onkologi och strålningsvetenskap, Enheten för nuklearmedicin och PET.
    Nilsson, Olle
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Bone healing of severe acetabular defects after revision arthroplasty2009Inngår i: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 80, nr 2, s. 179-183Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND AND PURPOSE: Healing of acetabular bone grafts may be difficult to assess in conventional radiographs. We used PET to analyze healing of morselized bone allografts, impacted in large osteolytic acetabular defects at revision arthroplasty. PATIENTS AND METHODS: 7 cases had a cup revision because of loosening, with repair of a segmental defect using a perforated, wide and thin plate. The osteolytic acetabulum was impacted with morselized bone allograft before cementing a polyethylene cup. [(18)F]-fluoride PET scans were used to monitor bone healing inside the graft bed 1 week, 4 weeks, and 12 months after surgery. The contralateral pelvic bone above the acetabulum was used as reference. A second group of 4 cases was analyzed for bone-forming activity in the state of mechanical loosening of an acetabular component of a THA. RESULTS: Preoperatively, the uptake was raised by 64% compared to the reference. 1 week after surgery it was increased by 77% in segmental regions, while the uptake was at the reference level in cavitary regions. After 4 months the uptake was increased by 91% in cavitary regions and by 117% in segmental regions. 1 year after surgery, the increase in uptake was 20% in both regions. All implants were stable on radiographs. INTERPRETATION: We found PET to be a sensitive and useful method for evaluation of the spatial and temporal development of bone formation.

  • 147423.
    Ulloa Andersson, Sofie
    et al.
    Högskolan Kristianstad, Sektionen för Hälsa och Samhälle.
    Nilsson, Maria
    Högskolan Kristianstad, Sektionen för Hälsa och Samhälle.
    Rubin, Sandra
    Högskolan Kristianstad, Sektionen för Hälsa och Samhälle.
    Mötet mellan hemlösa personer och vårdpersonal2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Bakgrund: Att leva som hemlös kan innebära hälsoproblem. Forskning visar att hemlösa på grund av dåligt bemötande inte söker sig till vården. Mötet med hemlösa personer ska bygga på respekt och omtanke. Vårdpersonal behöver därför vara medvetna om och reflektera över beroendet av varandra i mötet. Kunskap och förståelse för hemlösa personers problematik kan bidra till att förbättra omvårdnaden. Syfte: Att beskriva mötet mellan hemlösa personer och vårdpersonal. Metod: Studien utfördes som en allmän litteraturstudie och tretton vetenskapliga studier granskades, analyserades och delades in i tre kategorier. Resultat: Resultatet visade att respekt för värdighet och integritet, upplevelser av tillit och respekt för självbestämmande påverkade mötet mellan hemlösa personer och vårdpersonal. Slutsats: En ökad kunskap om problematiken i mötet mellan hemlösa personer och vårdpersonal behövs för att kunna förverkliga målet om lika vård på lika villkor.

  • 147424.
    Ullsten, Alexandra
    Kungl. Musikhögskolan, Institutionen för musik, pedagogik och samhälle.
    "Det finns ett språk bortom orden": en kunskapsöversikt av musikterapeutisk rehabilitering av skador i prosodi och pragmatik vid högersidiga traumatiska hjärnskador2010Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
  • 147425.
    Ullsten, Alexandra
    Örebro universitet, Musikhögskolan. Music and Art Therapy Department, Värmland County Council, Karlstad, Sweden.
    Family-centred music intervention - an emotional factor that modulates, modifies and alleviates infants' pain experiences2017Inngår i: Acta Paediatrica, ISSN 0803-5253, E-ISSN 1651-2227, Vol. 106, nr 3, s. 361-362Artikkel i tidsskrift (Fagfellevurdert)
  • 147426.
    Ullsten, Alexandra
    et al.
    Örebro universitet, Musikhögskolan. Centre for Clinical Research, Värmland County Council, Karlstad, Sweden.
    Eriksson, Mats
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Klässbo, Maria
    Centre for Clinical Research, Värmland County Council, Karlstad, Sweden.
    Volgsten, Ulrik
    Örebro universitet, Musikhögskolan.
    Live music therapy with lullaby singing as affective support during venepuncture: A case study with microanalysis of two premature born infants2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Introduction: Acute and repeated pain has long-term negative impact on infants’ development and future behaviour. The use of analgesic drugs has negative side-effects, which emphasizes the need for complementary approaches to pain management.

    Objective: The objectives were to analyze the live lullaby singing for two premature infants during venepuncture in comparison to standard care only, and the infants’ physiological and affective responses emerging before, during and after this procedure.

    Methods: Preterm and ill term infants (n=38) were subjected to venepuncture with and without live infant-directed lullaby singing, in a randomised order with a cross over design. Physiological data were collected and the procedures were videotaped. Two premature infants’ behavioural and physiological responses as well asthe live-performed lullaby, were analysed in-depth with microanalysis and with the pain assessment tool Behavioral Indicators of Infant Pain (BIIP).Results: Live singing with premature infants is a social communicative interaction. If the vocal performance is predictable and regular from start, it may optimize homeostasis during painful procedures.

    Conclusion: Since emotional regulation is a central feature of music therapy this case study brings important clinical implications for how the affective interaction between the music therapist or the parent and the infant should be composed during painful procedures.Pain involves the interaction of biopsychosocial and situational factors, therefore more research is needed to explore the potential benefits of music therapy including the role of the parents.

  • 147427.
    Ullsten, Alexandra
    et al.
    Örebro universitet, Musikhögskolan. Landstinget i Värmland, Karlstad, Sweden.
    Eriksson, Mats
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Klässbo, Maria
    Centrum för klinisk forskning, Landstinget i Värmland, Karlstad, Sweden.
    Volgsten, Ulrik
    Örebro universitet, Musikhögskolan.
    Live music therapy with lullaby singing as affective support during venepuncture. A case study with microanalysis of two premature born infants.2015Konferansepaper (Fagfellevurdert)
  • 147428.
    Ullsten, Alexandra
    et al.
    Örebro universitet, Musikhögskolan. Landstinget i Värmland, Karlstad, Sweden.
    Eriksson, Mats
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Klässbo, Maria
    Centrum för klinisk forskning, Landstinget i Värmland, Karlstad, Sweden.
    Volgsten, Ulrik
    Örebro universitet, Musikhögskolan.
    Live music therapy with lullaby singing as affective support during venepuncture. A case study with microanalysis of two premature born infants.2015Konferansepaper (Fagfellevurdert)
  • 147429.
    Ullsten, Alexandra
    et al.
    Örebro universitet, Musikhögskolan. Landstinget i Värmland, Karlstad, Sweden.
    Eriksson, Mats
    Örebro universitet, Institutionen för hälsovetenskap och medicin. Örebro universitet, Institutionen för hälsovetenskaper.
    Klässbo, Maria
    Centrum för klinisk forskning, Landstinget i Värmland, Karlstad, Sweden.
    Volgsten, Ulrik
    Örebro universitet, Musikhögskolan.
    Live music therapy with lullaby singing during painful procedures in neonatal care2017Konferansepaper (Annet vitenskapelig)
  • 147430.
    Ullsten, Alexandra
    et al.
    Örebro universitet, Musikhögskolan. Värmland County Council, Karlstad, Sweden.
    Hugoson, Pernilla
    Department of Music, University of Jyväskylä, Jyväskylä, Finland.
    Forsberg, Malin
    Department of Women's and Children's Health, Karolinska Institutet, Stockholm, sweden.
    Forzelius, Lisa
    Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
    Klässbo, Maria
    Clinical Research Center, Värmland County Council, Karlstad, Sweden.
    Olsson, Emma
    Örebro universitet, Institutionen för medicinska vetenskaper.
    Volgsten, Ulrik
    Örebro universitet, Musikhögskolan.
    Westrup, Björn
    Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
    Ådén, Ulrika
    Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
    Bergqvist, Lena
    Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
    Eriksson, Mats
    Örebro universitet, Institutionen för hälsovetenskaper. Region Örebro län.
    Efficacy of Live Lullaby Singing During Procedural Pain in Preterm and Term Neonates2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Background: Acute and repeated pain has long-term negative impact on infants’ development and future behaviour. The use of analgesic drugs has negative side-effects, which emphasizes the need for complementary approaches to pain management.

    Aim: This study is the first clinical trial measuring if live lullaby singing can influence behavioural and physiological pain responses during venepuncture in preterm and term neonates.

    Method: Preterm and term infants (n=38) were subjected to venepuncture with and without live lullaby singing, in a randomised order with a cross over design. Parent-preferred lullabies were performed live and standard care was provided for all neonates. Behavioural and physiological pain responses were assessed.

    Results: The live lullaby singing did not show a statistically significant effect on the infants’ pain score. There was a significantly calmer breathing pattern in the lullaby intervention versus the control condition in the pre-needle stage. There were non-significant indications of fewer and shorter skin punctures with lullaby singing.

    Conclusions: The additive effect of live lullaby singing has not been shown to alleviate infants’ behavioural pain responses during venepuncture; however nor has it been shown to be harmful. More research is needed to explore the potential benefits of music therapy including the role of the parents.

  • 147431.
    Ullsten, Alexandra
    et al.
    Örebro universitet, Musikhögskolan. Centre for Clinical Research, Värmland County Council, Karlstad, Sweden.
    Hugosson, Pernilla
    Department of Music, University of Jyväskylä, Jyväskylä, Finland; Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden .
    Forsberg, Malin
    County Council of Dalarna, Mora Hospital, Mora, Sweden.
    Forzelius, Lisa
    County Council of Västernorrland, Sundsvall Hospital, Sundsvall, Sweden.
    Klässbo, Maria
    Centre for Clinical Research, Värmland County Council, Karlstad, Sweden.
    Olsson, Emma
    Örebro universitet, Institutionen för hälsovetenskaper. Region Örebro län. Department of Pediatrics, Örebro University Hospital, Örebro, Sweden.
    Volgsten, Ulrik
    Örebro universitet, Musikhögskolan.
    Westrup, Björn
    Department of Women’s and Children’s Health, Karolinska Institute, Karolinska University Hospital-Danderyd, Stockholm, Sweden.
    Ådén, Ulrika
    Neonatal Research Unit, Department of Women’s and Children’s Health, Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden.
    Bergqvist, Lena
    Department of Clinical Science, Intervention and Technology, Unit of Pediatrics, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
    Eriksson, Mats
    Örebro universitet, Institutionen för hälsovetenskaper.
    Efficacy of Live Lullaby Singing During Procedural Pain in Preterm and Term Neonates2017Inngår i: Music and Medicine, ISSN 1943-8621, Vol. 9, nr 2, s. 73-85Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This clinical trial tested the pain relieving effect of live lullaby singing on behavioral and physiological pain responses during venepuncture in 38 preterm and full term neonates. Acute and repeated pain, as well as the use of analgesic drugs, may have long-term negative impact on infants’ development and future behaviour. This emphasizes the need for complementary approaches to pain management such as music therapy.

    Parent-preferred lullabies were performed live and standard care was provided for all neonates. Behavioral responses with regard to pain were assessed with Premature Infant Pain Profile-Revised (PIPP-R) and Behavioral Indicators of Infant Pain (BIIP). Heart rate, respiratory rate and oxygen saturation were measured each tenth second.

    Although the live lullaby singing did not show a statistically significant effect on the infants’ pain score, there was a significantly calmer breathing pattern in the lullaby intervention versus the control condition in the pre-needle stage, showing a non-significant trend towards higher oxygen saturation levels and calmer heart rate in the lullaby intervention versus the control condition in the pre-needle stage. There were non-significant indications of fewer and shorter skin punctures with lullaby singing. More research is needed to explore such positive trends in the data.

  • 147432.
    Ullsten, Henrik
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymera material.
    Processing and Development of Wheat Gluten Plastics2008Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

     Renewable packaging materials are of interest for a more sustainable environment. Wheat gluten is one of the most interesting candidates to replace petroleum-based oxygen-barrier polymers for packaging applications. The high amount of hydrogen bonds makes wheat gluten interesting as oxygen barrier films with sufficient elastomeric mechanical properties. Wheat gluten based materials are homogeneous, mechanically strong and relatively water insoluble compared with other biological materials. Several studies of wheat gluten films have been performed on solution cast films and a few studies have been executed on compression molding. Extrusion, without solvents, is the most common and fastest processing method for the production of packaging films. In order to develop wheat gluten films to commercially competitive material it is crucial to make the material extrudable.The temperature window for extrusion of glycerol-plasticized wheat gluten was increased by the use of salicylic acid, a known scorch retarder and radical scavenger. Small effects of shear-induced heating during extrusion at the higher temperatures suggested that the acid acted as a lubricant and viscosity reducer. The latter was suggested to originate primarily from the salicylic-acid-induced reduction in the degree of protein aggregation/crosslinking, as indicated by size-exclusion high-performance liquid chromatography and chemiluminescence. Electron paramagnetic resonance spectroscopy on extruded films indicated that the beneficial effect of salicylic acid was due to its radical scavenging effect. The complex shear modulus increased more slowly with increasing salicylic acid content above 110-120°C, indicating that the aggregation/crosslinking rate was slower with salicylic acid, i.e. that it did have a scorch-retarding effect, besides yielding a lower final degree/complexity of aggregation.Sodium hydroxide was used as an additive to be able to extrude gluten at alkaline conditions. The oxygen barrier, at dry conditions, was improved significantly with the addition of sodium hydroxide. Oxygen transmission rate measurements, tensile tests, protein solubility, glycerol migration, infrared spectroscopy and electrophoresis were used to assess the properties of the extrudate. It was observed that the extrudate with 3 wt.% sodium hydroxide had the most suitable combination of properties, low oxygen permeability, large strain at break and relatively small aging-induced changes in mechanical properties, the reason probably due to high protein aggregation and low plasticizer migration.As an alternative method to get alkaline conditions ammonium hydroxide was added. It resulted in a three times stronger film compared to the pure gluten glycerol material and had an oxygen barrier that can favorably be compared with these of oriented polyethylene terephtalat or Nylon 66.Several plasticizers were examined in a screening test where the extrusion properties were predicted in a plasticorder. The temperature and melt viscosity were recorded during the kneading. The most promising plasticizers were chosen to further studies with tensile tests. Glycerol was shown to be the most efficient plasticizer for thermoformed gluten films.In order to use wheat gluten as a packaging material, it is important to be able to seal it. Wheat gluten films, molded at 100–130°C, were sealed by impulse sealing at 120– 175°C. The lap-shear and peel strength of the sealed films were evaluated. The lapshear strength was greater than or similar to that of polyethylene film, although the peel strength was poorer.

  • 147433. Ullsten, Sara
    Evaluation of Progesterone Receptor Membrane Component 1 as a potential fertility and/or ovulation marker2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 147434.
    Ullsten, Sara
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    The Impact of Pancreatic Islet Vascular Heterogeneity on Beta Cell Function and Disease2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Diabetes Mellitus is a group of complex and heterogeneous metabolic disorders characterized by hyperglycemia. Even though the condition has been extensively studied, its causes and complex pathologies are still not fully understood. The occurring damage to the pancreatic islets is strikingly heterogeneous. In type 1 diabetes, the insulin producing beta cells are all destroyed within some islets, and similarly in type 2 diabetes, some islets may be severely affected by amyloid. At the same time other islets, in the near vicinity of the ones that are affected by disease, may appear fully normal in both diseases. Little is known about this heterogeneity in susceptibility to disease between pancreatic islets. This thesis examines the physiological and pathophysiological characteristics of islet subpopulations.

    Two subpopulations of islets were studied; one constituting highly vascularized islets with superior beta cell functionality, and one of low-oxygenated islets with low metabolic activity. The highly functional islets were found to be more susceptible to cellular stress both in vitro and in vivo, and developed more islet amyloid when metabolically challenged. Highly functional islets preferentially had a direct venous drainage, facilitating the distribution of islet hormones to the peripheral tissues. Further, these islets had an increased capacity for insulin secretion at low glucose levels, a response that was observed abolished in patients with recent onset type 1 diabetes.  The second investigated islet subpopulation, low-oxygenated islets, was found to be an over time stable subpopulation of islets with low vascular density and beta cell proliferation.

    In summary, two subpopulations of islets can be identified in the pancreas based on dissimilarities in vascular support and blood flow. These subpopulations appear to have different physiological functions of importance for the maintenance of glucose homeostasis. However, they also seem to differ in vulnerability, and a preferential death of the highly functional islets may accelerate the progression of both type 1 and type 2 diabetes.

  • 147435.
    Ullsten, Sara
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Bohman, Sara
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Oskarsson, Marie E
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Nilsson, K Peter R
    Linkoping Univ, Dept Chem, Linkoping, Sweden.
    Westermark, Gunilla
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Carlsson, Per-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Transplantation och regenerativ medicin.
    Islet amyloid deposits preferentially in the highly functional and most blood-perfused islets.2017Inngår i: Endocrine Connections, ISSN 2049-3614, E-ISSN 2049-3614, Vol. 6, nr 7, s. 458-468Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Islet amyloid and beta cell death in type 2 diabetes are heterogeneous events, where some islets are affected early in the disease process, whereas others remain visibly unaffected. This study investigated the possibility that inter-islet functional and vascular differences may explain the propensity for amyloid accumulation in certain islets. Highly blood-perfused islets were identified by microspheres in human islet amyloid polypeptide expressing mice fed a high-fat diet for three or 10 months. These highly blood-perfused islets had better glucose-stimulated insulin secretion capacity than other islets and developed more amyloid deposits after 10 months of high-fat diet. Similarly, human islets with a superior release capacity formed more amyloid in high glucose culture than islets with a lower release capacity. The amyloid formation in mouse islets was associated with a higher amount of prohormone convertase 1/3 and with a decreased expression of its inhibitor proSAAS when compared to islets with less amyloid. In contrast, levels of prohormone convertase 2 and expression of its inhibitor neuroendocrine protein 7B2 were unaltered. A misbalance in prohormone convertase levels may interrupt the normal processing of islet amyloid polypeptide and induce amyloid formation. Preferential amyloid load in the most blood-perfused and functional islets may accelerate the progression of type 2 diabetes.

  • 147436.
    Ullsten, Sara
    et al.
    Uppsala University, Sweden.
    Bohman, Sara
    Uppsala University, Sweden.
    Oskarsson, Marie E.
    Uppsala University, Sweden.
    Nilsson, Peter
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Westermark, Gunilla T.
    Uppsala University, Sweden.
    Carlsson, Per-Ola
    Uppsala University, Sweden.
    Islet amyloid deposits preferentially in the highly functional and most blood-perfused islets2017Inngår i: Endocrine Connections, ISSN 2049-3614, E-ISSN 2049-3614, Vol. 6, nr 7, s. 458-468Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Islet amyloid and beta cell death in type 2 diabetes are heterogeneous events, where some islets are affected early in the disease process, whereas others remain visibly unaffected. This study investigated the possibility that inter-islet functional and vascular differences may explain the propensity for amyloid accumulation in certain islets. Highly blood-perfused islets were identified by microspheres in human islet amyloid polypeptide expressing mice fed a high-fat diet for three or 10 months. These highly blood-perfused islets had better glucose-stimulated insulin secretion capacity than other islets and developed more amyloid deposits after 10 months of high-fat diet. Similarly, human islets with a superior release capacity formed more amyloid in high glucose culture than islets with a lower release capacity. The amyloid formation in mouse islets was associated with a higher amount of prohormone convertase 1/3 and with a decreased expression of its inhibitor proSAAS when compared to islets with less amyloid. In contrast, levels of prohormone convertase 2 and expression of its inhibitor neuroendocrine protein 7B2 were unaltered. A misbalance in prohormone convertase levels may interrupt the normal processing of islet amyloid polypeptide and induce amyloid formation. Preferential amyloid load in the most blood-perfused and functional islets may accelerate the progression of type 2 diabetes.

  • 147437.
    Ullsten, Sara
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Espes, Daniel
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Quach, My
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Fex, Malin
    Lund University, Lund University Diabetes Center, Department of Clinical Sciences.
    Sandberg, Monica
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Carlsson, Per-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Heterogeneities in vascularity and function between pancreatic islets may explain dissimilar propensities for disease development in type 1 diabetesManuskript (preprint) (Annet vitenskapelig)
  • 147438.
    Ullsten, Sara
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Grapensparr, Liza
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Sandberg, Monica
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Carlsson, Per-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Transplantation och regenerativ medicin.
    Schwann cells regulate angiogenesis and blood vessel structure in native and transplanted pancreatic2015Inngår i: Xenotransplantation, ISSN 0908-665X, E-ISSN 1399-3089, Vol. 22, s. S46-S46Artikkel i tidsskrift (Annet vitenskapelig)
  • 147439.
    Ullsten, Sara
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Grapensparr, Liza
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Sandberg, Monica
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Carlsson, Per-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Schwann Cells Regulate Angiogenesis And Blood Vessel Structure In Native And Transplanted Pancreatic Islets2015Inngår i: Transplantation, ISSN 0041-1337, E-ISSN 1534-6080, Vol. 99, nr 11, s. S75-S75Artikkel i tidsskrift (Annet vitenskapelig)
  • 147440.
    Ullsten, Sara
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Lau, Joey
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Carlsson, Per-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Decreased beta cell proliferation and vascular density in a subpopulation of low-oxygenated rat isletsManuskript (preprint) (Annet vitenskapelig)
  • 147441.
    Ullsten, Sara
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Lau, Joey
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Carlsson, Per-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Transplantation och regenerativ medicin.
    Vascular heterogeneity between native rat pancreatic islets is responsible for differences in survival and revascularisation post transplantation2015Inngår i: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 58, nr 1, s. 132-139Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    AIMS/HYPOTHESIS: Highly blood-perfused islets have been observed to be the most functional islets in the native pancreas. We hypothesised that differences in vascular support of islets in donor pancreases influence their susceptibility to cellular stress and capacity for vascular engraftment after transplantation. METHODS: Highly blood-perfused islets in rats were identified by injection of microspheres into the ascending aorta before islet isolation. Cell death was evaluated after in vitro cytokine or hypoxia exposure, and 2days post transplantation. One month post transplantation, islet engraftment, including vascular density, blood perfusion and oxygen tension (pO2) in the tissue, was evaluated. RESULTS: Microsphere-containing islets had a similar frequency of cell death during standard culture conditions but increased cell death after exposure to cytokines and hypoxia in comparison with other islets. Two days after transplantation the percentage of apoptotic or necrotic cells was also higher in grafts of such islets and 1month post transplantation these grafts were composed of substantially more connective tissue. Grafts of highly blood-perfused islets in the native pancreas regained a higher vascular density, blood perfusion and pO2 in comparison with grafts of other islets. CONCLUSIONS/INTERPRETATION: Native islets that are highly blood-perfused regained this feature after transplantation, indicating a superior capacity for revascularisation and post-transplant function. However, the same group of islets was more vulnerable to different kinds of cellular stress, which limited their early survival post transplantation. Preferential death of these most active islets may contribute to the high number of islets needed to provide cure with islet transplantation.

  • 147442.
    Ullsten, Sara
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Lau, Joey
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Welsh, Nils
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
    Carlsson, Per-Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Vascular Heterogeneity Between Native Pancreatic Islets Determines Their Fate of Survival and Revascularization Posttransplantation2013Inngår i: Transplantation, ISSN 0041-1337, E-ISSN 1534-6080, Vol. 96, nr 6, s. S21-S21Artikkel i tidsskrift (Annet vitenskapelig)
  • 147443.
    Ullström, Hannah
    et al.
    Linköpings universitet, Institutionen för samhälls- och välfärdsstudier. Linköpings universitet, Medicinska fakulteten.
    Hanning, Jessica
    Linköpings universitet, Institutionen för samhälls- och välfärdsstudier. Linköpings universitet, Medicinska fakulteten.
    Sjuksköterskans upplevelse av vilka omvårdnadsbehov patienter i palliativ vård har och hur dessa behov kan tillgodoses2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Bakgrund: Det är viktigt att det finns kunskap om palliativ vård inom alla verksamheter då patienter i palliativ vård finns överallt inom vården. Finns inte kunskapen kan patientens behov lätt missas. Författarna till den här studien ville få en förståelse för vilka omvårdnadsbehov sjuksköterskor upplever att patienten har i det palliativa skedet.

    Syfte: Syftet var att undersöka vilka omvårdnadsbehov sjuksköterskor upplever att patienten har i det palliativa skedet och hur dessa behov kan tillgodoses.

    Metod: En kvalitativ intervjustudie genomfördes på ett sjukhus. Sju sjuksköterskor intervjuades och intervjumaterialet analyserades med manifest innehållsanalys.

    Resultat: Resultatet visade att sjuksköterskorna upplevde att patienten i palliativ vård har två övergripande omvårdnadsbehov. Dessa är psykosociala behov och omvårdnadsbehov. I psykosociala behov ingår autonomi, behov av uppmärksamhet, kommunikation och socialt nätverk. I omvårdnadsbehov ingår förutom behovet av omvårdnad även behov av omvårdnadskompetent personal.

    Konklusion: Studien visade att sjuksköterskorna upplevde att patienten i det palliativa skedet har behov av symptomlindring, samtal, bevarad autonomi, att bli behandlad som en individ, att ha ett stödjande socialt nätverk och kompetent personal.

  • 147444.
    Ulltin, Jenny
    et al.
    Ersta Sköndal högskola, Institutionen för vårdvetenskap.
    Carlsson, Sabina
    Ersta Sköndal högskola, Institutionen för vårdvetenskap.
    Sjuksköterskans erfarenheter av att vårda kvinnor som blivit utsatta för våld i en nära relation: En litteraturöversikt2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Background: Domestic violence is a globally widespread problem. One in three women will at some point during their lifetime suffer from domestic violence. These women, who come from all groups of society, often seek contact with health care and therefore the nurse plays a vital role in caring for these women.

    Aim: The aim of this study was to describe nurses’ experiences of caring for women subjected to domestic violence.

    Method: Literature review based on twelve original articles.

    Result: The result is presented in four main themes: Lack of knowledge and education, The nurse’s approach and attitude in the encounter with women who suffered domestic violence, The nurse’s emotional challenges in the encounter with women who suffered domestic violence and The nurse’s experience of identification of domestic violence victims.

    Discussion: Education is important on several levels for the nurse's work with domestic violence victims. Education is required in order to efficiently identify the women, manage emotional impact and to respond to women in a professional manner.

  • 147445. Ullum, H.
    et al.
    Kamper-Jorgensen, M.
    Edgren, G.
    Rostgaard, K.
    Melbye, M.
    Nyrén, O.
    Norda, Rut
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för klinisk immunologi och transfusionsmedicin.
    Hjalgrim, H.
    FREQUENCY OF BLOOD DONATION DOES NOT AFFECT BLOOD DONOR SURVIVAL2010Inngår i: Vox Sanguinis, ISSN 0042-9007, E-ISSN 1423-0410, Vol. 99, s. 184-185Artikkel i tidsskrift (Annet vitenskapelig)
  • 147446.
    Ullum, Henrik
    et al.
    Copenhagen Univ Hosp, Ctr Clin Invest, Dept Clin Immunol, Copenhagen, Denmark..
    Rostgaard, Klaus
    Statens Serum Inst, Dept Epidemiol Res, DK-2300 Copenhagen, Denmark..
    Kamper-Jorgensen, Mads
    Statens Serum Inst, Dept Epidemiol Res, DK-2300 Copenhagen, Denmark.;Univ Copenhagen, Dept Publ Hlth, Copenhagen, Denmark..
    Reilly, Marie
    Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden..
    Melbye, Mads
    Statens Serum Inst, Dept Epidemiol Res, DK-2300 Copenhagen, Denmark..
    Nyren, Olof
    Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden..
    Norda, Rut
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Klinisk immunologi.
    Edgren, Gustaf
    Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden.;Karolinska Univ Hosp, Hematol Ctr, Stockholm, Sweden..
    Hjalgrim, Henrik
    Statens Serum Inst, Dept Epidemiol Res, DK-2300 Copenhagen, Denmark..
    Blood donation and blood donor mortality after adjustment for a healthy donor effect2015Inngår i: Transfusion, ISSN 0041-1132, E-ISSN 1537-2995, Vol. 55, nr 10, s. 2479-2485Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND Studies have repeatedly demonstrated that blood donors experience lower mortality than the general population. While this may suggest a beneficial effect of blood donation, it may also reflect the selection of healthy persons into the donor population. To overcome this bias, we investigated the relation between blood donation frequency and mortality within a large cohort of blood donors. In addition, our analyses also took into consideration the effects of presumed health differences linked to donation behavior.

    STUDY DESIGN AND METHODS Using the Scandinavian Donation and Transfusion database (SCANDAT), we assessed the association between annual number of donations in 5-year windows and donor mortality by means of Poisson regression analysis. The analyses included adjustment for demographic characteristics and for an internal healthy donor effect, estimated among elderly donors exempted from continued donation because of age criteria.

    RESULTS Statistical analyses included 1,182,495 donors of whom 15,401 died during 9,526,627 person-years of follow-up. Analyses adjusted only for demographic characteristics showed a 18.6% reduction in mortality per additional annual donation (95% confidence interval [CI], 16.8%-20.4%). After additional adjustment for the internal healthy donor effect, each additional annual donation was associated with a 7.5% decreased mortality risk 7.5% (95% CI, 5.7%-9.4%).

    CONCLUSION We observed an inverse relationship between donation frequency and mortality. The magnitude of the association was reduced after adjustment for an estimate of self-selection in the donor population. Our observations indicate that repeated blood donation is not associated with premature death, but cannot be interpreted as conclusive evidence of a beneficial health effect.

  • 147447. Ullén, A
    et al.
    Sandström, P
    Riklund Åhlström, K
    Sundström, Birgitta
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap.
    Nilsson, B
    Ärlestig, L
    Stigbrand, T
    Use of anticytokeratin monoclonal antiidiotypic antibodies to improve tumor / non tumor ratio at experimental radioimmunolocalisation1995Inngår i: Cancer Research 1995;55: 5868s-5873sArtikkel i tidsskrift (Fagfellevurdert)
  • 147448.
    Ullén, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Klinisk immunologi.
    Strategies to improve cancer radioimmunotargeting1996Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Radioimmunotherapy (RIT) and radioimmunolocalisation (RIL) are developing and promising technologies to diagnose and treat tumours by use of radiolabelled antibodies targeting tumour specific antigens. The major reason why RIL and RIT not are efficient enough, is the comparatively low accumulation of radiolabelled antibodies in the tumours. Irrespective of the antigen - antibody system used, the maximal tumour uptake in humans is often limited to below 0.1 % of the total injected dose, with significant radionuclide remaining in the blood pool and extravascular fluid.

    In the present thesis, the following putative improvement techniques for radioimmunotargeting have been evaluated in an experimental model using HeLa cell-xenografted nude mice: 1) Repetitive, simultaneous targeting of different antigens, 2) Removal of non-targeting antibodies using secondary antiidiotypic antibodies, 3) Preinjection of unlabelled antibody to remove shedded antigen and 4) Use of fractionated antibody administration. By use of multiple injections of mixtures of two different 131I-labelled monoclonal antibodies targeting placental alkaline phosphatase (H7) and cytokeratin 8 (TS1), respectively, a significant tumour growth inhibition compared to controls, was obtained. In the treated group, a negligible increase in tumour volume was seen compared to the control group, in which a 20-fold increase was observed. Quantitative determinations of volume densities of viable tumour cells, necrotic cells and connective tissue demonstrated no significant differences in the relative proportions between the groups, indicating that the irradiation caused decelerated growth. Using hybridoma technology, monoclonal antiidiotypic antibodies were generated against both TS1 and H7. The in vitro and in vivo effects of these antibodies, aH7 and aTSl, were investigated. Both these antiidiotypes were found to generate stable complexes with the radiolabelled idiotypic antibody, as revealed by gel-electrophoresis and autoradiography. Using biosensor technology (BIAcore, Pharmacia) the interactions were followed in real time and the association rate-, dissociation rate-, and affinity constants between the reactants were determined. In vivo, the antiidiotypes promoted a rapid dose dependent clearance of the 125I-labelled idiotypes with a decrease in total body radioactivity and concomitant dramatic increase in non-protein bound 125I excreted in the urine. The syngeneic monoclonal antiidiotypic antibody αTSl, was furthermore evaluated as a secondary clearing antibody at radioimmunolocalisation. Injection of αTSl in a molar ratio of 0.5-0.75:1 to TS1, 24 hours after the 125I-labelled TS1 improved the tumour to normal tissue ratio 2-3 fold. This was due to a decreased level of total body radioactivity as well as a slight decrease in tumour-radioactivity. A model describing the kinetics of the involved components, i.e. the antigen, the idiotype and the antiidiotype was presented. It is concluded that high affinity monoclonal antiidiotypes can be used as tools to regulate the levels of idiotypic antibodies in vivo. This strategy, combined with preinjection of non­labelled idiotypic antibodies, caused accumulated doses of 3 Gy to the tumour and 0.9 Gy to non tumour tissues as calculated for 125I-labelled antibodies (80 MBq/mg) by MIRD formalism based on repetitive quantitative radioimmunoscintigraphies. By approaching the maximal tolerated whole body radiation dose for mice (i.e. 6 Gy), it can be estimated that doses up to 20 Gy are possible to obtain following one single injection of labelled antibody. It was furthermore demonstrated that a single bolus injection of antibody is to be preferred, compared to exactly the same dose divided into three or ten fractions. Thus, not only the dose of radioactivity, but also the amount of antibody should be considered for fractionated RIT.

    In summary, the thesis demonstrates that several techniques can be used to improve radioimmunolocalisation and to approach the proposed 70 Gy required to sterilise tumours at radioimmunotherapy.

  • 147449. Ullén, Fredrik
    et al.
    de Manzano, Örjan
    Theorell, Töres
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Stressforskningsinstitutet.
    Harmat, Lazlo
    The physiology of Effortless Attention: Correlates of State Flow and Flow Proneness.2010Inngår i: Effortless Attention: A New Perspective in the Cognitive Science of Attention and Action / [ed] Bruya Brian, Bradford Books , 2010, 1, s. 205-218Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 147450.
    Ullén, Fredrik
    et al.
    Department of Woman and Child Health, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
    Forsman, Lea
    Department of Woman and Child Health, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
    Blom, Örjan
    Department of Woman and Child Health, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
    Karabanov, Anke
    Department of Woman and Child Health, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
    Madison, Guy
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Intelligence and variability in a simple timing task share neural substrates in the prefrontal white matter2008Inngår i: Journal of Neuroscience, ISSN 0270-6474, EISSN 1529-2401, Vol. 28, nr 16, s. 4238-4243Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    General intelligence is correlated with the mean and variability of reaction time in elementary cognitive tasks, as well as with performance on temporal judgment and discrimination tasks. This suggests a link between the temporal accuracy of neural activity and intelligence. However, it has remained unclear whether this link reflects top-down mechanisms such as attentional control and cognitive strategies or basic neural properties that influence both abilities. Here, we investigated whether millisecond variability in a simple, automatic timing task, isochronous tapping, correlates with intellectual performance and, using voxel based morphometry, whether these two tasks share neuroanatomical substrates. Stability of tapping and intelligence were correlated and related to regional volume in overlapping right prefrontal white matter regions. These results suggest a bottom-up explanation of the link between temporal stability and intellectual performance, where more extensive prefrontal connectivity underlies individual differences in both variables.

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