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  • 1. Affatato, S.
    et al.
    Leardini, W.
    Jedenmalm, Anneli
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Ruggeri, O.
    Toni, A.
    Larger diameter bearings reduce wear in metal-on-metal hip implants2007Inngår i: Clinical Orthopaedics and Related Research, ISSN 0009-921X, E-ISSN 1528-1132, nr 456, s. 153-158Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Metal-on-metal hip arthroplasty has the longest clinical history of all total arthroplasties. We asked whether large diameter femoral heads would result in less wear than those with small diameters. We also asked if there is a threshold diameter that ensures good wear behavior. We tested three batches of cast high-carbon cobalt-chromium-molybdenum hip implants (28 mm, 36 min, and 54 min diameters) in a hip simulator for 5 million cycles. We used bovine serum as lubricant and weighed the samples at regular intervals during testing. The 28-mm configuration had almost twice the wear of the 54-mm configuration, but we observed no difference between the 36-mm and the 54-mm configurations. The similarity in the wear performances of the larger configurations supports the presence of a threshold diameter that ensures good wear behavior.

  • 2. Aitken, Candice L.
    et al.
    Gorniak, Richard J. T.
    New York University.
    Kramer, Elissa L.
    New York University.
    Noz, Marilyn E.
    New York University.
    Farrell, Eward J.
    IBM Research.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Reddy, David P.
    Comparison of three methods used for fusion of SPECT-CT images of liver matastases1998Inngår i: Fusion98, International Conference on Multisource-Mulltisensor Information Fusion / [ed] Hamid R. Arabnia and Dongping (Daniel) Zhu, CSREA Press , 1998, s. 435-442Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We compare three methods for fusing SPECT-CT images: ImageMatch - an automatic three-dimensional/two-dimensional method developed by Focus Imaging; IBM Visualization Data Explorer - a three-diemensional interactive method developed by Internation Business Machines, Inc.; and qsh - an interactive three-dimensional/two-dimensional method developed at New York University. While many fusion methods have proved successful for registering brain images, most methods have been less successful for thoracic and abdominal images. We use images of liver metastases obtained with a radiolabeled breast tumor-directed antibody to illustrate the strengths and weakness of the methods reviewed. The images used are typical clinical images from eigth patients. We conclude that an optimal image fusion program should combine the strengths of each of the methods reviewed.

  • 3. Aitken, Candice L.
    et al.
    Mahmoud, Faaiza
    McGuinness, Georgeann
    Kramer, Elissa L.
    Maguire, Gerald Q. Jr.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Noz, Marilyn E.
    New York University.
    Tumor localization and image registration of F-18FDG coincidence detection scans with computed tomographic scans2002Inngår i: Clinical Nuclear Medicine, ISSN 0363-9762, E-ISSN 1536-0229, Vol. 27, nr 4, s. 275-282Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management. Methods: F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated. Results: All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%. Conclusions: Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.

  • 4.
    Aitken, Candice L.
    et al.
    New York University.
    McGuinness, Georgeann
    New York University.
    Siddiqui, Faaiza
    New York University.
    Ton, Anthony
    New York University.
    Kramer, Elissa L
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Tumor localization and image registration of 18-FDG SPECT scans with CT scans1999Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 40, nr 5, s. 290P-291PArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    PURPOSE:

    The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management.

    METHODS:

    F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated.

    RESULTS:

    All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm +/- 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%.

    CONCLUSIONS:

    Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.

  • 5.
    Akan, Rabia
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Frisk, Thomas
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Lundberg, Fabian
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Ohlin, Hanna
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Johansson, Ulf
    Lund Univ, MAX IV Lab, S-22100 Lund, Sweden..
    Li, Kenan
    SLAC Natl Accelerator Lab, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA..
    Sakdinawat, Anne
    SLAC Natl Accelerator Lab, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA..
    Vogt, Ulrich
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Metal-Assisted Chemical Etching and Electroless Deposition for Fabrication of Hard X-ray Pd/Si Zone Plates2020Inngår i: Micromachines, ISSN 2072-666X, E-ISSN 2072-666X, Vol. 11, nr 3, artikkel-id 301Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Zone plates are diffractive optics commonly used in X-ray microscopes. Here, we present a wet-chemical approach for fabricating high aspect ratio Pd/Si zone plate optics aimed at the hard X-ray regime. A Si zone plate mold is fabricated via metal-assisted chemical etching (MACE) and further metalized with Pd via electroless deposition (ELD). MACE results in vertical Si zones with high aspect ratios. The observed MACE rate with our zone plate design is 700 nm/min. The ELD metallization yields a Pd density of 10.7 g/cm3, a value slightly lower than the theoretical density of 12 g/cm3. Fabricated zone plates have a grid design, 1:1 line-to-space-ratio, 30 nm outermost zone width, and an aspect ratio of 30:1. At 9 keV X-ray energy, the zone plate device shows a first order diffraction efficiency of 1.9%, measured at the MAX IV NanoMAX beamline. With this work, the possibility is opened to fabricate X-ray zone plates with low-cost etching and metallization methods.

  • 6.
    Akkus, Zeynettin
    et al.
    KTH. Department of Medical Physics, University Hospitals of Leicester, NHS Trust, Leicester, UK.
    Ramnarine, K. V.
    Dynamic assessment of carotid plaque motion2010Inngår i: Ultrasound, ISSN 1742-271X, Vol. 18, nr 3, s. 140-147Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Assessment of dynamic plaque behaviour may help identify vulnerable carotid plaque before rupture and hence has potential clinical value for screening patients at risk of stroke. The aim of this study was to develop non-invasive ultrasound methods for quantifying dynamic plaque and vessel wall behaviour and assess their potential clinical utility. Ultrasound data from the carotid arteries of one normal subject and four patients with atherosclerotic disease were acquired using a 10 MHz linear array transducer recording raw RF/IQ data at a frame rate up to 80 Hz for 3-6 seconds. Image reconstruction and processing was performed using Matlab. Speckle tracking techniques were developed to characterize: (1) intraplaque deformation; and (2) plaque surface and vessel wall motion. Speckle tracking techniques were able to measure the range of intraplaque tissue deformation (-1.3 to 1.7 mm), plaque surface displacement (0.2-0.7 mm) and vessel wall radial strain (0.02-0.13) throughout the cardiac cycle. The feasibility of using an intraplaque deformation parameter, based on the deformation of a square template, is demonstrated. Speckle tracking techniques can be used to assess dynamic carotid plaque behaviour. Further work is required to evaluate how best to quantify biomechanical behaviour to help predict plaque rupture and hence improve risk stratification models for stroke.

  • 7.
    Alagic, Zlatan
    et al.
    Karolinska Univ Hosp, Funct Unit Musculoskeletal Radiol Funct Imaging &, S-17176 Stockholm, Sweden.;Karolinska Inst, Clin Sci Intervent & Technol CLINTEC, Stockholm, Sweden..
    Alagic, Haris
    Karolinska Inst, Inst Mol Med & Surg MMK, Diagnost Radiol, Stockholm, Sweden..
    Bujila, Robert
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Srivastava, Subhash
    Karolinska Univ Hosp, Funct Unit Musculoskeletal Radiol Funct Imaging &, S-17176 Stockholm, Sweden..
    Jasim, Saif
    Karolinska Univ Hosp, Funct Unit Musculoskeletal Radiol Funct Imaging &, S-17176 Stockholm, Sweden..
    Lindqvist, Maria
    Karolinska Univ Hosp, Funct Unit Musculoskeletal Radiol Funct Imaging &, S-17176 Stockholm, Sweden..
    Wick, Marius C.
    Karolinska Univ Hosp, Funct Unit Musculoskeletal Radiol Funct Imaging &, S-17176 Stockholm, Sweden.;Karolinska Inst, Inst Mol Med & Surg MMK, Diagnost Radiol, Stockholm, Sweden..
    First experiences of a low-dose protocol for CT-guided musculoskeletal biopsies combining different radiation dose reduction techniques2020Inngår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 61, nr 1, s. 28-36Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background The use of computed tomography (CT) for image guidance during biopsies is a powerful approach. The method is, however, often associated with a significant level of radiation exposure to the patient and operator. Purpose To investigate if a low-dose protocol for CT-guided musculoskeletal (MSK) biopsies, including a combination of different radiation dose (RD) techniques, is feasible in a clinical setting. Material and Methods Fifty-seven patients underwent CT-guided fine-needle aspiration cytology (FNAC) utilizing the low-dose protocol (group A). A similar number of patients underwent CT-guided FNAC using the reference protocol (group B). Between-group comparisons comprised radiation dose, success rate, image quality parameters, and workflow. Results In group A, the mean total dose-length product (DLP) was 41.2 +/- 2.9 mGy*cm, which was statistically significantly lower than of group B (257.4 +/- 22.0 mGy*cm), corresponding to a mean dose reduction of 84% (P<0.001). The mean CTDIvol for the control scans were 1.88 +/- 0.09 mGy and 13.16 +/- 0.40 mGy for groups A and B, respectively (P < 0.001). The success rate in group A was 91.2% and 87.9% in group B (P = 0.56). No negative effect on image-quality parameters, time of FNAC, and number of control scans were found. Conclusion We successfully developed a low-dose protocol for CT-guided MSK biopsies that maintains diagnostic accuracy and image quality at a fraction of the RD compared to the reference biopsy protocol at our clinic.

  • 8.
    Alcala, Yvonne
    et al.
    New York Medical College .
    Olivecrona, Henrik
    Karolinska.
    Olivecrona, Lotta
    Karolinska.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    Zeleznik, Michael P.
    Sollerman, Christer
    Sahlgrenska University Hospital, Göteborg, Sweden.
    Qualifying CT for wrist arthroplasty: Extending techniques for total hip arthroplasty to total wrist arthroplasty2005Inngår i: Medical Imaging 2005: Image Processing, Pt 1-3 / [ed] Fitzpatrick, JM; Reinhardt, JM, SPIE - The International Sooceity for Optical Engineeering , 2005, Vol. 5747, s. 1155-1164Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The purpose of this study was to extend previous work to detect migration of total wrist arthroplasty non-invasively, and with greater accuracy. Two human cadaverous arms, each with a cemented total wrist implant, were used in this study. In one of the arms, I mm tantalum balls were implanted, six in the carpal bones and five in the radius. Five CT scans of each arm were acquired, changing the position of the arm each time to mimic different positions patients might take on repeated examinations. Registration of CT volume data sets was performed using an extensively validated, 3D semi-automatic volume fusion tool in which co-homologous point pairs (landmarks) are chosen on each volume to be registered. Three sets of ten cases each were obtained by placing landmarks on 1) bone only (using only arm one), 2) tantalum implants only, and 3) bone and tantalum implants (both using only arm two). The accuracy of the match was assessed visually in 2D and 3D, and numerically by calculating the distance difference between the actual position of the transformed landmarks and their ideal position (i.e., the reference landmark positions). All cases were matched visually within one width of cortical bone and numerically within one half CT voxel (0.32 mm, p = 0.05). This method matched only the bone/arm and not the prosthetic component per se, thus making it possible to detect prosthetic movement and wear. This method was clinically used for one patient with pain. Loosening of the carpal prosthetic component was accurately detected and this was confirmed at surgery.

  • 9.
    Al-Farsi, Hissa M.
    et al.
    Karolinska Inst, Dept Lab Med, Div Clin Microbiol, Stockholm, Sweden.;Minist Hlth, Cent Publ Hlth Labs, Muscat, Oman..
    Al-Adwani, Salma
    Karolinska Inst, Dept Lab Med, Div Clin Microbiol, Stockholm, Sweden.;Sultan Qaboos Univ, Coll Agr & Marine Sci, Dept Anim & Vet Sci, Muscat, Oman..
    Ahmed, Sultan
    Karolinska Inst, Dept Lab Med, Div Clin Microbiol, Stockholm, Sweden..
    Vogt, Carmen
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik. KTH, Skolan för bioteknologi (BIO), Centra, Albanova VinnExcellence Center for Protein Technology, ProNova.
    Ambikan, Anoop T.
    Karolinska Inst, Dept Lab Med, Div Clin Microbiol, Stockholm, Sweden..
    Leber, Anna
    Karolinska Inst, Dept Lab Med, Div Clin Microbiol, Stockholm, Sweden..
    Al-Jardani, Amina
    Minist Hlth, Cent Publ Hlth Labs, Muscat, Oman..
    Al-Azri, Saleh
    Minist Hlth, Cent Publ Hlth Labs, Muscat, Oman..
    Al-Muharmi, Zakariya
    Sultan Qaboos Univ, Coll Med & Hlth Sci, Dept Microbiol & Immunol, Muscat, Oman..
    Toprak, Muhammet
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik. KTH, Skolan för bioteknologi (BIO), Centra, Albanova VinnExcellence Center for Protein Technology, ProNova.
    Giske, Christian G.
    Karolinska Inst, Dept Lab Med, Div Clin Microbiol, Stockholm, Sweden.;Karolinska Univ Hosp, Dept Clin Microbiol, Stockholm, Sweden..
    Bergman, Peter
    Karolinska Inst, Dept Lab Med, Div Clin Microbiol, Stockholm, Sweden.;Karolinska Univ Hosp, Immunodeficiency Unit, Infect Dis Clin, Stockholm, Sweden..
    Effects of the Antimicrobial Peptide LL-37 and Innate Effector Mechanisms in Colistin-Resistant Klebsiella pneumoniae With mgrB Insertions2019Inngår i: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 10, artikkel-id 2632Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background Colistin is a polypeptide antibiotic drug that targets lipopolysaccharides in the outer membrane of Gram-negative bacteria. Inactivation of the mgrB-gene is a common mechanism behind colistin-resistance in Klebsiella pneumoniae (Kpn). Since colistin is a cyclic polypeptide, it may exhibit cross-resistance with the antimicrobial peptide LL-37, and with other innate effector mechanisms, but previous results are inconclusive. Objective To study potential cross-resistance between colistin and LL-37, as well as with other innate effector mechanisms, and to compare virulence of colistin-resistant and susceptible Kpn strains. Materials/Methods Carbapenemase-producing Kpn from Oman (n = 17) were subjected to antimicrobial susceptibility testing and whole genome sequencing. Susceptibility to colistin and LL-37 was studied. The surface charge was determined by zeta-potential measurements and the morphology of treated bacteria was analyzed with electron microscopy. Bacterial survival was assessed in human whole blood and serum, as well as in a zebrafish infection-model. Results Genome-analysis revealed insertion-sequences in the mgrB gene, as a cause of colistin resistance in 8/17 isolates. Colistin-resistant (Col-R) isolates were found to be more resistant to LL-37 compared to colistin-susceptible (Col-S) isolates, but only at concentrations >= 50 mu g/ml. There was no significant difference in surface charge between the isolates. The morphological changes were similar in both Col-R and Col-S isolates after exposure to LL-37. Finally, no survival difference between the Col-R and Col-S isolates was observed in whole blood or serum, or in zebrafish embryos. Conclusion Cross-resistance between colistin and LL-37 was observed at elevated concentrations of LL-37. However, Col-R and Col-S isolates exhibited similar survival in serum and whole blood, and in a zebrafish infection-model, suggesting that cross-resistance most likely play a limited role during physiological conditions. However, it cannot be ruled out that the observed cross-resistance could be relevant in conditions where LL-37 levels reach high concentrations, such as during infection or inflammation.

  • 10.
    Aljadi, Zenib
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab. Department of Clinical Science and Education, Karolinska Institutet, Stockholm, Sweden.
    Kalm, Frida
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab. Department of Clinical Science and Education, Karolinska Institutet, Stockholm, Sweden;Sachs´ Children and Youth Hospital, Södersjukhuset, Stockholm, Sweden.
    Nilsson, Caroline
    Karolinska Inst, Dept Clin Sci & Educ, Stockholm, Sweden.;Soder Sjukhuset, Sachs Children & Youth Hosp, Stockholm, Sweden..
    Winqvist, Ola
    Karolinska Univ Hosp, Dept Clin Immunol, Stockholm, Sweden..
    Russom, Aman
    KTH, Centra, Science for Life Laboratory, SciLifeLab. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Nanobioteknologi.
    Lundahl, Joachim
    Karolinska Inst, Dept Clin Sci & Educ, Stockholm, Sweden.;Soder Sjukhuset, Sachs Children & Youth Hosp, Stockholm, Sweden..
    Nopp, Anna
    Karolinska Inst, Dept Clin Sci & Educ, Stockholm, Sweden.;Soder Sjukhuset, Sachs Children & Youth Hosp, Stockholm, Sweden..
    A novel tool for clinical diagnosis of allergy operating a microfluidic immunoaffinity basophil activation test technique2019Inngår i: Clinical Immunology, ISSN 1521-6616, E-ISSN 1521-7035, Vol. 209, artikkel-id UNSP 108268Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Basophil Activation Test (BAT) is a valuable allergy diagnostic tool but is time-consuming and requires skilled personnel and cumbersome processing, which has limited its clinical use. We therefore investigated if a microfluidic immunoaffinity BAT (miBAT) technique can be a reliable diagnostic method. Blood was collected from allergic patients and healthy controls. Basophils were challenged with negative control, positive control (anti-FccRI), and two concentrations of a relevant and non-relevant allergen. CD203c and CD63 expression was detected by fluorescent microscopy and flow cytometry. In basophils from allergic patients the CD63% was significantly higher after allergen activation as compared to the negative control (p < .0001-p = .0004). Activation with non-relevant allergen showed equivalent CD63% expression as the negative control. Further, the miBAT data were comparable to flow cytometry. Our results demonstrate the capacity of the miBAT technology to measure different degrees of basophil allergen activation by quantifying the CD63% expression on captured basophils.

  • 11.
    Aljadi, Zenib
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab. Karolinska Inst, Dept Clin Sci & Educ, Stockholm, Sweden; Soder Sjukhuset, Stockholm, Sweden .
    Kalm, Frida
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab. Karolinska Inst, Dept Clin Sci & Educ, Stockholm, Sweden; Soder Sjukhuset, Stockholm, Sweden.
    Ramachandraiah, Harisha
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Nopp, Anna
    Karolinska Inst, Dept Clin Sci & Educ, Stockholm, Sweden.;Soder Sjukhuset, Stockholm, Sweden..
    Lundahl, Joachim
    Karolinska Inst, Dept Clin Sci & Educ, Stockholm, Sweden.;Soder Sjukhuset, Stockholm, Sweden..
    Russom, Aman
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap, Nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Microfluidic Immunoaffinity Basophil Activation Test for Point-of-Care Allergy Diagnosis2019Inngår i: Journal of Applied Laboratory Medicine (JALM), ISSN 2475-7241, Vol. 4, nr 2, s. 152-163Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: The flow cytometry-based basophil activation test (BAT) is used for the diagnosis of allergic response. However, flow cytometry is time-consuming, requiring skilled personnel and cumbersome processing, which has limited its use in the clinic. Here, we introduce a novel microfluidic-based immunoaffinity BAT (miBAT) method. Methods: The microfluidic device, coated with anti-CD203c, was designed to capture basophils directly from whole blood. The captured basophils are activated by anti-FceRI antibody followed by optical detection of CD63 expression (degranulation marker). The device was first characterized using a basophil cell line followed by whole blood experiments. Weevaluated the device with ex vivo stimulation of basophils in whole blood from healthy controls and patients with allergies and compared it with flow cytometry. Results: The microfluidic device was capable of capturing basophils directly from whole blood followed by in vitro activation and quantification of CD63 expression. CD63 expression was significantly higher (P = 0.0002) in on-chip activated basophils compared with nonactivated cells. The difference in CD63 expression on anti-FceRI-activated captured basophils in microfluidic chip was significantly higher (P = 0.03) in patients with allergies compared with healthy controls, and the results were comparable with flow cytometry analysis (P = 0.04). Furthermore, there was no significant difference of CD63% expression in anti-FceRI-activated captured basophils in microfluidic chip compared with flow cytometry. Conclusions: We report on the miBAT. This device is capable of isolating basophils directly from whole blood for on-chip activation and detection. The new miBAT method awaits validation in larger patient populations to assess performance in diagnosis and monitoring of patients with allergies at the point of care.

  • 12. Alkharusi, Amira
    et al.
    Yu, Shengze
    KTH, Skolan för bioteknologi (BIO).
    Landazuri, Natalia
    Zadjali, Fahad
    Davodi, Belghis
    Nystrom, Thomas
    Gräslund, Torbjörn
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Rahbar, Afsar
    Norstedt, Gunnar
    Stimulation of prolactin receptor induces STAT-5 phosphorylation and cellular invasion in glioblastoma multiforme2016Inngår i: OncoTarget, ISSN 1949-2553, E-ISSN 1949-2553, Vol. 7, nr 48, s. 79558-79569Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor in humans and is characterized with poor outcome. In this study, we investigated components of prolactin (Prl) system in cell models of GBM and in histological tissue sections obtained from GBM patients. Expression of Prolactin receptor (PrlR) was detected at high levels in U251-MG, at low levels in U87-MG and barely detectable in U373 cell lines and in 66% of brain tumor tissues from 32 GBM patients by immunohistochemical technique. In addition, stimulation of U251-MG and U87-MG cells but not U373 with Prl resulted in increased STAT5 phosphorylation and only in U251-MG cells with increased cellular invasion. Furthermore, STAT5 phosphorylation and cellular invasion induced in Prl stimulated cells were significantly reduced by using a Prl receptor antagonist that consists of Prl with four amino acid replacements. We conclude that Prl receptor is expressed at different levels in the majority of GBM tumors and that blocking of PrlR in U251-MG cells significantly reduce cellular invasion.

  • 13. Altai, M.
    et al.
    Honarvar, H.
    Wallberg, H.
    Strand, J.
    Varasteh, Z.
    Orlova, A.
    Dunas, F.
    Sandstrom, M.
    Rosestedt, M.
    Löfblom, John
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Tolmachev, V.
    Ståhl, Stefan
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Selection of an optimal cysteine-containing peptide-based chelator for labeling of Affibody molecules with Re-1882013Inngår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 40, s. S219-S220Artikkel i tidsskrift (Annet vitenskapelig)
  • 14.
    Altai, M.
    et al.
    Uppsala Univ, Imuunol Genet & Pathol, Uppsala, Sweden..
    Liu, Hao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap. KTH, Div Prot Technol, Stockholm, Sweden..
    Orlova, A.
    Div Mol Imaging, Dept Med Chem, Uppsala, Sweden..
    Tolmachev, V.
    Uppsala Univ, Imuunol Genet & Pathol, Uppsala, Sweden..
    Gräslund, Torbjörn
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Proteinvetenskap. KTH, Div Prot Technol, Stockholm, Sweden..
    Improving of molecular design of a novel Affibody-fused HER2-recognising anticancer toxin using radionuclide-based techniques2016Inngår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 43, s. S178-S178Artikkel i tidsskrift (Annet vitenskapelig)
  • 15. Altai, M.
    et al.
    Perols, Anna
    KTH, Skolan för bioteknologi (BIO), Molekylär Bioteknologi (stängd 20130101).
    Eriksson Karlström, Amelie
    KTH, Skolan för bioteknologi (BIO), Molekylär Bioteknologi (stängd 20130101).
    Sandström, M.
    Boschetti, F.
    Orlova, A.
    Tolmachev, V.
    Evaluation of a maleimido derivative of NODAGA for site-specific In-111-labeling of Affibody molecules2011Inngår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 38, s. S146-S146Artikkel i tidsskrift (Annet vitenskapelig)
  • 16. Altai, M.
    et al.
    Strand, J.
    Rosik, Daniel
    KTH, Skolan för bioteknologi (BIO), Molekylär Bioteknologi (stängd 20130101).
    Selvaraju, R.
    Eriksson Karlström, Amelie
    KTH, Skolan för bioteknologi (BIO), Molekylär Bioteknologi (stängd 20130101).
    Orlova, A.
    Tolmachev, V.
    Comparative evaluation of anti-HER2 affibody molecules labeled with 68Ga and 111In using maleimido derivatives of DOTA and NODAGA.2012Inngår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 39, s. S299-S299Artikkel i tidsskrift (Fagfellevurdert)
  • 17. Altai, M.
    et al.
    Wallberg, H.
    Honarvar, H.
    Strand, J.
    Orlova, A.
    Löfblom, John
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Varasteh, Z.
    Sandström, M.
    Ståhl, Stefan
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Tolmachev, V.
    Re-188-Z(HER2: V2), a promising targeting agent against HER2-expressing tumors: in vitro and in vivo assessment2013Inngår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 40, s. S119-S119Artikkel i tidsskrift (Annet vitenskapelig)
  • 18.
    Altai, M.
    et al.
    Inst Immunol Genet & Pathol, Uppsala, Sweden..
    Westerlund, Kristina
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Konijnenberg, M.
    Erasmus MC, Dept Nucl Med & Radiol, Rotterdam, Netherlands..
    Mitran, B.
    Div Mol Imaging, Uppsala, Sweden..
    Oroujeni, M.
    Inst Immunol Genet & Pathol, Uppsala, Sweden..
    de Jong, M.
    Erasmus MC, Dept Nucl Med & Radiol, Rotterdam, Netherlands..
    Eriksson Karlström, Amelie
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Orlova, A.
    Div Mol Imaging, Uppsala, Sweden..
    Tolmachev, V.
    Inst Immunol Genet & Pathol, Uppsala, Sweden..
    Pretargeted radionuclide therapy of HER2-expressing SKOV-3 human xenografts using an Affibody molecule-based PNA-mediated pretargeting2017Inngår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 44, s. S142-S142Artikkel i tidsskrift (Annet vitenskapelig)
  • 19. Altai, M.
    et al.
    Westerlund, Kristina
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Velletta, J.
    Mitran, B.
    Honarvar, H.
    Eriksson Karlström, Amelie
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Evaluation of affibody molecule-based PNA-mediated radionuclide pretargeting: Development of an optimized conjugation protocol and 177Lu labeling2017Inngår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 54, s. 1-9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Introduction We have previously developed a pretargeting approach for affibody-mediated cancer therapy based on PNA–PNA hybridization. In this article we have further developed this approach by optimizing the production of the primary agent, ZHER2:342-SR-HP1, and labeling the secondary agent, HP2, with the therapeutic radionuclide 177Lu. We also studied the biodistribution profile of 177Lu-HP2 in mice, and evaluated pretargeting with 177Lu-HP2 in vitro and in vivo. Methods The biodistribution profile of 177Lu-HP2 was evaluated in NMRI mice and compared to the previously studied 111In-HP2. Pretargeting using 177Lu-HP2 was studied in vitro using the HER2-expressing cell lines BT‐474 and SKOV-3, and in vivo in mice bearing SKOV-3 xenografts. Results and conclusion Using an optimized production protocol for ZHER2:342-SR-HP1 the ligation time was reduced from 15 h to 30 min, and the yield increased from 45% to 70%. 177Lu-labeled HP2 binds specifically in vitro to BT474 and SKOV-3 cells pre-treated with ZHER2:342-SR-HP1. 177Lu-HP2 was shown to have a more rapid blood clearance compared to 111In-HP2 in NMRI mice, and the measured radioactivity in blood was 0.22 ± 0.1 and 0.68 ± 0.07%ID/g for 177Lu- and 111In-HP2, respectively, at 1 h p.i. In contrast, no significant difference in kidney uptake was observed (4.47 ± 1.17 and 3.94 ± 0.58%ID/g for 177Lu- and 111In-HP2, respectively, at 1 h p.i.). Co-injection with either Gelofusine or lysine significantly reduced the kidney uptake for 177Lu-HP2 (1.0 ± 0.1 and 1.6 ± 0.2, respectively, vs. 2.97 ± 0.87%ID/g in controls at 4 h p.i.). 177Lu-HP2 accumulated in SKOV-3 xenografts in BALB/C nu/nu mice when administered after injection of ZHER2:342-SR-HP1. Without pre-injection of ZHER2:342-SR-HP1, the uptake of 177Lu-HP2 was about 90-fold lower in tumor (0.23 ± 0.08 vs. 20.7 ± 3.5%ID/g). The tumor-to-kidney radioactivity accumulation ratio was almost 5-fold higher in the group of mice pre-injected with ZHER2:342-SR-HP1. In conclusion, 177Lu-HP2 was shown to be a promising secondary agent for affibody-mediated tumor pretargeting in vivo.

  • 20. Altai, Mohamed
    et al.
    Perols, Anna
    KTH, Skolan för bioteknologi (BIO), Molekylär Bioteknologi.
    Eriksson Karlström, Amelie
    KTH, Skolan för bioteknologi (BIO), Molekylär Bioteknologi.
    Sandström, Mattias
    Boschetti, Frederic
    Orlova, Anna
    Tolmachev, Vladimir
    Preclinical evaluation of anti-HER2 Affibody molecules site-specifically labeled with In-111 using a maleimido derivative of NODAGA2012Inngår i: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 39, nr 4, s. 518-529Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Introduction: Affibody molecules have demonstrated potential for radionuclide molecular imaging. The aim of this study was to synthesize and evaluate a maleimido derivative of the 1,4,7-triazacyclononane-l-glutaric acid-4,7-diacetic acid (NODAGA) for site-specific labeling of anti-HER2 Affibody molecule. Methods: The maleimidoethylmonoamide NODAGA (MMA-NODAGA) was synthesized and conjugated to Z(HER2:2395) Affibody molecule having a C-terminal cysteine. Labeling efficiency, binding specificity to and cell internalization by HER2-expressing cells of [In-111-MMA-NODAGA-Cys(61)]-Z(HER2:2395) were studied. Biodistribution of [In-111-MMA-NODAGA-Cys(61)]-Z(HER2:2395) and [In-111-MMA-DOTA-Cys(61)]-Z(HER2:2395) was compared in mice. Results: The affinity of [MMA-NODAGA-Cys(61)]-Z(HER2:2395) binding to HER2 was 67 pM. The In-1111-labeling yield was 99.6%+/- 0.5% after 30 min at 60 degrees C. [In-111-MMA-NODAGA-Cys(61)]-Z(HER2:2395) bound specifically to HER2-expressing cells in vitro and in vivo. Tumor uptake of [In-111-MMA-NODAGA-Cys(61)]-ZHER(2:2395) in mice bearing DU-145 xenografts (4.7%+/- 0.8% ID/g) was lower than uptake of [In-111-MMA-DOTA-Cys(61)]-Z(HER2:2395) (7.5%+/- 1.6% ID/g). However, tumor-to-organ ratios were higher for [In-111-MMA-NODAGA-Cys(61)]-Z(HER2:2395) due to higher clearance rate from normal tissues. Conclusions: MMA-NODAGA is a promising chelator for site-specific labeling of targeting proteins containing unpaired cysteine. Appreciable influence of chelators on targeting properties of Affibody molecules was demonstrated.

  • 21. Altai, Mohamed
    et al.
    Perols, Anna
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Tsourma, Maria
    Mitran, Bogdan
    Honarvar, Hadis
    Robillard, Marc
    Rossin, Raffaella
    ten Hoeve, Wolter
    Lubberink, Mark
    Orlova, Anna
    Karlström, Amelie Eriksson
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Tolmachev, Vladimir
    Feasibility of Affibody-Based Bioorthogonal Chemistry Mediated Radionuclide Pretargeting2016Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 57, nr 3, s. 431-436Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Affibody molecules constitute a new class of probes for radionuclide tumor targeting. The small size of Affibody molecules is favorable for rapid localization in tumors and clearance from circulation. However, high renal reabsorption of Affibody molecules prevents the use of residualizing radiometals, including several promising low-energy (beta- and alpha-emitters, for radionuclide therapy. We tested a hypothesis that Affibody-based pretargeting mediated by a bioorthogonal interaction between trans-cyclooctene (TCO) and tetrazine would provide higher accumulation of radiometals in tumor xenografts than in the kidneys. Methods: TCO was conjugated to the anti-human epidermal growth factor receptor 2 (HER2) Affibody molecule Z(2395). DOTA-tetrazine was labeled with In-111 and Lu-177. In vitro pretargeting was studied in HER2-expressing SKOV-3 and BT474 cell lines. In vivo studies were performed on BALB/C nu/nu mice bearing SKOV-3 xenografts. Results: I-125-Z(2395)-TCO bound specifically to HER2-expressing cells in vitro with an affinity of 45 +/- 16 pM. In-111-tetrazine bound specifically and selectively to Z(2325)-TCO pretreated cells. In vivo studies demonstrated HER2-specific I-125-Z(2395)-TCO accumulation in xenografts. TCO-mediated In-111-tetrazine localization was shown in tumors, when the radiolabeled tracer was injected 4 h after an injection of Z(2395)-TCO. At 1 h after injection, the tumor uptake of In-111-tetrazine and Lu-177-tetrazine was approximately 2-fold higher than the renal uptake. Pretargeting provided more than a 56-fold reduction of renal uptake of In-111 in comparison with direct targeting. Conclusion: The feasibility of Affibody-based bioorthogonal chemistry-mediated pretargeting was demonstrated. The use of pre-targeting provides a substantial reduction of radiometal accumulation in kidneys, creating preconditions for palliative radionuclide therapy.

  • 22. Altai, Mohamed
    et al.
    Wållberg, Helena
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Honarvar, Hadis
    Strand, Joanna
    Orlova, Anna
    Varasteh, Zohreh
    Sandström, Mattias
    Löfblom, John
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Larsson, Erik
    Strand, Sven-Erik
    Lubberink, Mark
    Ståhl, Stefan
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi. Uppsala University, Sweden.
    Tolmachev, Vladimir
    Re-188-Z(HER2:V2), a Promising Affibody-Based Targeting Agent Against HER2-Expressing Tumors: Preclinical Assessment2014Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 55, nr 11, s. 1842-1848Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Affibody molecules are small (7 kDa) nonimmunoglobulin scaffold proteins with favorable tumor-targeting properties. Studies concerning the influence of chelators on biodistribution of Tc-99m-labeled Affibody molecules demonstrated that the variant with a C-terminal glycyl-glycyl-glycyl-cysteine peptide-based chelator (designated Z(HER2:V2)) has the best biodistribution profile in vivo and the lowest renal retention of radioactivity. The aim of this study was to evaluate Re-188-Z(HER2:v2) as a potential candidate for radionuclide therapy of human epidermal growth factor receptor type 2 (HER2)-expressing tumors. Methods: Z(HER2:V2) was labeled with Re-188 using a gluconate-containing kit. Targeting of HER2-overexpressing SKOV-3 ovarian carcinoma xenografts in nude mice was studied for a dosimetry assessment. Results: Binding of Re-188-Z(HER2:V2) to living SKOV-3 cells was demonstrated to be specific, with an affinity of 6.4 +/- 0.4 pM. The biodistribution study showed a rapid blood clearance (1.4 +/- 0.1 percentage injected activity per gram [%ID/g] at 1 h after injection). The tumor uptake was 14 +/- 2, 12 +/- 2, 5 +/- 2, and 1.8 +/- 0.5 %IA/g at 1, 4, 24, and 48 h after injection, respectively. The in vivo targeting of HER2-expressing xenografts was specific. Already at 4 h after injection, tumor uptake exceeded kidney uptake (2.1 +/- 0.2 %IA/g). Scintillation-camera imaging showed that tumor xenografts were the only sites with prominent accumulation of radioactivity at 4 h after injection. Based on the biokinetics, a dosimetry evaluation for humans suggests that Re-188-Z(HER2:v2) would provide an absorbed dose to tumor of 79 Gy without exceeding absorbed doses of 23 Gy to kidneys and 2 Gy to bone marrow. This indicates that future human radiotherapy studies may be feasible. Conclusion: (188)ReZ(HER2:v2) can deliver high absorbed doses to tumors without exceeding kidney and bone marrow toxicity limits.

  • 23.
    Anderlind, Eva
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Människa-datorinteraktion, MDI (stängd 20111231).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Sallnäs Pysander, Eva-Lotta
    KTH, Skolan för datavetenskap och kommunikation (CSC), Numerisk Analys och Datalogi, NADA.
    Lind, Bengt K.
    Karolinska Institute, Department of Medical Radiation Physics.
    Maguire, Gerald Q. Jr.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Will haptic feedback speed up medical imaging? An application to radiation treatment planning2008Inngår i: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 47, nr 1, s. 32-37Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Haptic technology enables us to incorporate the sense of touch into computer applications, providing an additional input/output channel. The purpose of this study was to examine if haptic feedback can help physicians and other practitioners to interact with medical imaging and treatment planning systems. A haptic application for outlining target areas (a key task in radiation therapy treatment planning) was implemented and then evaluated via a controlled experiment with ten subjects. Even though the sample size was small, and the application only a prototype, results showed that haptic feedback can significantly increase (p0.05) the speed of outlining target volumes and organs at risk. No significant differences were found regarding precision or perceived usability. This promising result warrants further development of a full haptic application for this task. Improvements to the usability of the application as well as to the forces generated have been implemented and an experiment with more subjects is planned.

  • 24.
    Anderlind, Eva
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Människa-datorinteraktion, MDI (stängd 20111231).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Sallnäs Pysander, Eva-Lotta
    KTH, Skolan för datavetenskap och kommunikation (CSC), Människa-datorinteraktion, MDI (stängd 20111231).
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Lind, Bengt K.
    Karolinska Institute, Medical Radiation Physics.
    The value of haptic feedback in medical imaging and treatment planning2006Inngår i: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 81, s. 1277-Artikkel i tidsskrift (Fagfellevurdert)
  • 25.
    Andersson, Ken G.
    et al.
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Oroujeni, Maryam
    Garousi, Javad
    Mitran, Bogdan
    Ståhl, Stefan
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Orlova, Anna
    Löfblom, John
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Tolmachev, Vladimir
    Feasibility of imaging of epidermal growth factor receptor expression with ZEGFR:2377 affibody molecule labeled with Tc-99m using a peptide-based cysteine-containing chelator2016Inngår i: International Journal of Oncology, ISSN 1019-6439, Vol. 49, nr 6, s. 2285-2293Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The epidermal growth factor receptor (EGFR) is overexpressed in a number of malignant tumors and is a molecular target for several specific anticancer antibodies and tyrosine kinase inhibitors. The overexpression of EGFR is a predictive biomarker for response to several therapy regimens. Radionuclide molecular imaging might enable detection of EGFR overexpression by a non-invasive procedure and could be used repeatedly. Affibody molecules are engineered scaffold proteins, which could be selected to have a high affinity and selectivity to predetermined targets. The anti-EGFR ZEGFR:2377 affibody molecule is a potential imaging probe for EGFR detection. The use of the generator-produced radionuclide Tc-99m should facilitate clinical translation of an imaging probe due to its low price, availability and favorable dosimetry of the radionuclide. In the present study, we evaluated feasibility of ZEGFR:2377 labeling with Tc-99m using a peptide-based cysteine-containing chelator expressed at the C-terminus of ZEGFR:2377. The label was stable in vitro under cysteine challenge. In addition, Tc-99m-ZEGFR:2377 was capable of specific binding to EGFR-expressing cells with high affinity (274 pM). Studies in BALB/C nu/nu mice bearing A431 xenografts demonstrated that Tc-99m-ZEGFR:2377 accumulates in tumors in an EGFR-specific manner. The tumor uptake values were 3.6 1 and 2.5 0.4% ID/g at 3 and 24 h after injection, respectively. The corresponding tumor-to-blood ratios were 1.8 0.4 and 8 3. The xenografts were clearly visualized at both time-points. This study demonstrated the potential of Tc-99m-labeled ZEGFR:2377 for imaging of EGFR in vivo.

  • 26.
    Andersson, Ken G.
    et al.
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Varasteh, Z.
    Rosenstedt, M.
    Rosestedt, M.
    Malm, M.
    KTH.
    Sandström, M.
    KTH.
    Tolmachev, V.
    Löfblom, John
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Ståhl, Stefan
    KTH, Skolan för bioteknologi (BIO), Proteinteknologi.
    Orlova, A.
    111In-labeled NOTA-conjugated Affibody molecules for visualization of HER3 expression in malignant tumors2014Inngår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 41, s. S311-S311Artikkel i tidsskrift (Annet vitenskapelig)
  • 27. Andersson, Malin
    et al.
    Jägervall, Karl
    Eriksson, Per
    Persson, Anders
    Granerus, Göran
    Wang, Chunliang
    Linköping Univ, Sweden.
    Smedby, Örjan
    Linköping Univ, Sweden.
    How to measure renal artery stenosis - a retrospective comparison of morphological measurement approaches in relation to hemodynamic significance2015Inngår i: BMC Medical Imaging, ISSN 1471-2342, E-ISSN 1471-2342, Vol. 15, artikkel-id 42Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Although it is well known that renal artery stenosis may cause renovascular hypertension, it is unclear how the degree of stenosis should best be measured in morphological images. The aim of this study was to determine which morphological measures from Computed Tomography Angiography (CTA) and Magnetic Resonance Angiography (MRA) are best in predicting whether a renal artery stenosis is hemodynamically significant or not. Methods: Forty-seven patients with hypertension and a clinical suspicion of renovascular hypertension were examined with CTA, MRA, captopril-enhanced renography (CER) and captopril test (Ctest). CTA and MRA images of the renal arteries were analyzed by two readers using interactive vessel segmentation software. The measures included minimum diameter, minimum area, diameter reduction and area reduction. In addition, two radiologists visually judged the diameter reduction without automated segmentation. The results were then compared using limits of agreement and intra-class correlation, and correlated with the results from CER combined with Ctest (which were used as standard of reference) using receiver operating characteristics (ROC) analysis. Results: A total of 68 kidneys had all three investigations (CTA, MRA and CER + Ctest), where 11 kidneys (16.2 %) got a positive result on the CER + Ctest. The greatest area under ROC curve (AUROC) was found for the area reduction on MRA, with a value of 0.91 (95 % confidence interval 0.82-0.99), excluding accessory renal arteries. As comparison, the AUROC for the radiologists' visual assessments on CTA and MRA were 0.90 (0.82-0.98) and 0.91 (0.83-0.99) respectively. None of the differences were statistically significant. Conclusions: No significant differences were found between the morphological measures in their ability to predict hemodynamically significant stenosis, but a tendency of MRA having higher AUROC than CTA. There was no significant difference between measurements made by the radiologists and measurements made with fuzzy connectedness segmentation. Further studies are required to definitely identify the optimal measurement approach.

    Fulltekst (pdf)
    Andersson 2015 renal artery stenosis
  • 28. Andersson, Thord
    et al.
    Romu, Thobias
    Karlsson, Anette
    Norén, Bengt
    Forsgren, Mikael F
    Smedby, Örjan
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinsk bildbehandling och visualisering. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning. Linköping University.
    Kechagias, Stergios
    Almer, Sven
    Lundberg, Peter
    Borga, Magnus
    Leinhard, Olof Dahlqvist
    Consistent intensity inhomogeneity correction in water-fat MRI2015Inngår i: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 42, nr 2Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    PURPOSE: To quantitatively and qualitatively evaluate the water-signal performance of the consistent intensity inhomogeneity correction (CIIC) method to correct for intensity inhomogeneities

    METHODS: Water-fat volumes were acquired using 1.5 Tesla (T) and 3.0T symmetrically sampled 2-point Dixon three-dimensional MRI. Two datasets: (i) 10 muscle tissue regions of interest (ROIs) from 10 subjects acquired with both 1.5T and 3.0T whole-body MRI. (ii) Seven liver tissue ROIs from 36 patients imaged using 1.5T MRI at six time points after Gd-EOB-DTPA injection. The performance of CIIC was evaluated quantitatively by analyzing its impact on the dispersion and bias of the water image ROI intensities, and qualitatively using side-by-side image comparisons.

    RESULTS: CIIC significantly ( P1.5T≤2.3×10-4,P3.0T≤1.0×10-6) decreased the nonphysiological intensity variance while preserving the average intensity levels. The side-by-side comparisons showed improved intensity consistency ( Pint⁡≤10-6) while not introducing artifacts ( Part=0.024) nor changed appearances ( Papp≤10-6).

    CONCLUSION: CIIC improves the spatiotemporal intensity consistency in regions of a homogenous tissue type.

  • 29. Andrade, Pedro Amarante
    et al.
    Wistbacka, Greta
    Larsson, Hans
    Sodersten, Maria
    Hammarberg, Britta
    Simberg, Susanna
    Svec, Jan G.
    Granqvist, Svante
    KTH, Skolan för teknik och hälsa (STH), Naturvetenskap och biomedicin. Karolinska Institutet, Sweden.
    The Flow and Pressure Relationships in Different Tubes Commonly Used for Semi-occluded Vocal Tract Exercises2016Inngår i: Journal of Voice, ISSN 0892-1997, E-ISSN 1873-4588, Vol. 30, nr 1, s. 36-41Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This experimental study investigated the back pressure (Pback) versus flow (U) relationship for 10 different tubes commonly used for semi-occluded vocal tract exercises, that is, eight straws of different lengths and diameters, a resonance tube, and a silicone tube similar to a Lax Vox tube. All tubes were assessed with the free end in air. The resonance tube and silicone tube were further assessed with the free end under water at the depths from 1 to 7 cm in steps of 1 cm. The results showed that relative changes in the diameter of straws affect Pback considerably more compared with the same amount of relative change in length. Additionally, once tubes are submerged into water, Pback needs to overcome the pressure generated by the water depth before flow can start. Under this condition, only a small increase in Pback was observed as the flow was increased. Therefore, the wider tubes submerged into water produced an almost constant Pback determined by the water depth, whereas the thinner straws in air produced relatively large changes to Pback as flow was changed. These differences may be taken advantage of when customizing exercises for different users and diagnoses and optimizing the therapy outcome.

  • 30.
    Andreasson, A.
    et al.
    Karolinska Inst Huddinge, Stockholm, Sweden..
    Uttervall, K.
    Karolinska Inst, Stockholm, Sweden..
    Liwing, J.
    Janssen AB, Sollentuna, Sweden..
    Alici, E.
    Karolinska Inst, Stockholm, Sweden..
    Näsman, Per
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE).
    Aschan, J.
    Janssen AB, Sollentuna, Sweden..
    Nahi, H.
    Karolinska Inst, Stockholm, Sweden..
    Bortezomib, response and retreatment in 1st, 2nd, 3rd and 4th line of treatment in patients with multiple myeloma2012Inngår i: Haematologica, ISSN 0390-6078, E-ISSN 1592-8721, Vol. 97, s. 610-610Artikkel i tidsskrift (Annet vitenskapelig)
  • 31.
    Arruda, Lucas C. M.
    et al.
    Karolinska Inst, Dept Clin Sci Intervent & Technol, Stockholm, Sweden..
    Gaballa, Ahmed
    Karolinska Inst, Dept Clin Sci Intervent & Technol, Stockholm, Sweden..
    Uhlin, Michael
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik. KTH, Centra, Science for Life Laboratory, SciLifeLab. Karolinska Inst, Dept Clin Sci Intervent & Technol, Stockholm, Sweden.;Karolinska Univ Hosp, Dept Immunol & Transfus Med, Stockholm, Sweden..
    Impact of gamma delta T cells on clinical outcome of hematopoietic stem cell transplantation: systematic review and meta-analysis2019Inngår i: Blood Advances, ISSN 2473-9529, Vol. 3, nr 21, s. 3436-3448Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Allogeneic hematopoietic stem cell transplantation (HSCT) using alpha beta T-/B-cell-depleted grafts recently emerged as a transplant strategy and highlighted the potential role of gamma delta T cells on HSCT outcomes. Our aim was to scrutinize available evidence of gamma delta T-cell impact on relapse, infections, survival, and acute graft-versus-host disease (aGVHD). We performed a systematic review and meta-analysis of studies assessing gamma delta T cells in HSCT. We searched PubMed, Web of Science, Scopus, and conference abstracts from inception to March 2019 for relevant studies. We included all studies that assessed gamma delta T cells associated with HSCT. Data were extracted independently by 2 investigators based on strict selection criteria. A random-effects model was used to pool outcomes across studies. Primary outcome was disease relapse. We also assessed infections, survival, and aGVHD incidence. The review was registered with PROSPERO (CRD42019133344). Our search returned 2412 studies, of which 11 (919 patients) were eligible for meta-analysis. Median follow-up was 30 months (interquartile range, 22-32). High gamma delta T-cell values after HSCT were associated with less disease relapse (risk ratio [RR], 0.58; 95% confidence interval [95% CI], 0.40-0.84; P = .004; I-2 = 0%), fewer viral infections (RR, 0.59; 95% CI, 0.43-0.82; P < .002; I-2 = 0%) and higher overall (HR, 0.28; 95% CI, 0.18-0.44; P < .00001; I-2 = 0%) and disease-free survivals (HR 0.29; 95% CI, 0.18-0.48; P < .00001; I-2 = 0%). We found no association between high gd T-cell values and aGVHD incidence (RR, 0.72; 95% CI, 0.41-1.27; P = .26; I-2 = 0%). In conclusion, high gd T cells after HSCT is associated with a favorable clinical outcome but not with aGVHD development, suggesting that gd T cells have a significant effect on the success of HSCT. This study was registered with PROSPERO as #CRD42019133344.

  • 32.
    Asem, Heba
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Material- och nanofysik, Funktionella material, FNM. Karolinska Inst, Sweden.
    Abd El-Fattah, Ahmed
    Nafee, Noha
    Zhao, Ying
    Khalil, Labiba
    Muhammed, Mamoun
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Material- och nanofysik, Funktionella material, FNM.
    Hassan, Moustapha
    Kandil, Sherif
    Development and biodistribution of a theranostic aluminum phthalocyanine nanophotosensitizer2016Inngår i: Photodiagnosis and Photodynamic Therapy, ISSN 1572-1000, E-ISSN 1873-1597, Vol. 13, s. 48-57Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Aluminum phthalocyanine (AlPc) is an efficient second generation photosensitizer (PS) with high fluorescence ability. Its use in photodynamic therapy (PDT) is hampered by hydrophobicity and poor biodistribution. Methods: AlPc was converted to a biocompatible nanostructure by incorporation into amphiphilic polyethylene glycol-polycaprolactone (PECL) copolymer nanoparticles, allowing efficient entrapment of the PS in the hydrophobic core, water dispersibility and biodistribution enhancement by PEG-induced surface characteristics. A series of synthesized PECL copolymers were used to prepare nanophotosensitizers with an average diameter of 66.5-99.1 nm and encapsulation efficiency (EE%) of 66.4-78.0%. One formulation with favorable colloidal properties and relatively slow release over 7 days was selected for in vitro photophysical assessment and in vivo biodistribution studies in mice. Results: The photophysical properties of AlPc were improved by encapsulating AlPc into PECL-NPs, which showed intense fluorescence emission at 687 nm and no AlPc aggregation has been induced after entrapment into the nanoparticles. Biodistribution of AlPc loaded NPs (AlPc-NPs) and free AlPc drug in mice was monitored by in vivo whole body fluorescence imaging and ex vivo organ imaging, with in vivo imaging system (IVIS). Compared to a AlPc solution in aqueous TWEEN 80 (2 w/v%), the developed nanophotosensitizer showed targeted drug delivery to lungs, liver and spleen as monitored by the intrinsic fluorescence of AlPc at different time points (1 h, 24 h and 48 h) post iv. administration. Conclusions: The AlPc-based copolymer nanoparticles developed offer potential as a single agent multifunctional theranostic nanophotosensitizer for PDT coupled with imaging-guided drug delivery and biodistribution, and possibly also fluorescence diagnostics.

  • 33.
    Astaraki, Mehdi
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning. Karolinska Inst, Dept Oncol Pathol, Karolinska Univ Sjukhuset, SE-17176 Stockholm, Sweden.
    Wang, Chunliang
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning.
    Buizza, Giulia
    Politecn Milan, Dept Elect Informat & Bioengn, Piazza Leonardo da Vinci 42, I-20133 Milan, Italy..
    Toma-Dasu, Iuliana
    Karolinska Inst, Dept Oncol Pathol, Karolinska Univ Sjukhuset, SE-17176 Stockholm, Sweden.;Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden..
    Lazzeroni, Marta
    Karolinska Inst, Dept Oncol Pathol, Karolinska Univ Sjukhuset, SE-17176 Stockholm, Sweden.;Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden..
    Smedby, Örjan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Medicinsk avbildning.
    Early survival prediction in non-small cell lung cancer from PET/CT images using an intra-tumor partitioning method2019Inngår i: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 60, s. 58-65Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: To explore prognostic and predictive values of a novel quantitative feature set describing intra-tumor heterogeneity in patients with lung cancer treated with concurrent and sequential chemoradiotherapy. Methods: Longitudinal PET-CT images of 30 patients with non-small cell lung cancer were analysed. To describe tumor cell heterogeneity, the tumors were partitioned into one to ten concentric regions depending on their sizes, and, for each region, the change in average intensity between the two scans was calculated for PET and CT images separately to form the proposed feature set. To validate the prognostic value of the proposed method, radiomics analysis was performed and a combination of the proposed novel feature set and the classic radiomic features was evaluated. A feature selection algorithm was utilized to identify the optimal features, and a linear support vector machine was trained for the task of overall survival prediction in terms of area under the receiver operating characteristic curve (AUROC). Results: The proposed novel feature set was found to be prognostic and even outperformed the radiomics approach with a significant difference (AUROC(sALop) = 0.90 vs. AUROC(radiomic) = 0.71) when feature selection was not employed, whereas with feature selection, a combination of the novel feature set and radiomics led to the highest prognostic values. Conclusion: A novel feature set designed for capturing intra-tumor heterogeneity was introduced. Judging by their prognostic power, the proposed features have a promising potential for early survival prediction.

  • 34.
    Atefi, Seyed Reza
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Electrical Bioimpedance cerebral monitoring. Preliminary results from measurements on stroke patients2012Inngår i: Engineering in Medicine and Biology Society (EMBC), 2012 Annual International Conference of the IEEE, IEEE , 2012, s. 126-129Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Electrical Bioimpedance Spectroscopy (EBIS) is currently used in different tissue characterization applications. In this work we aim to use EBIS to study changes in electrical properties of the cerebral tissues after an incident of hemorrhage/ischemic stroke. To do so a case-control study was conducted using six controls and three stroke cases. The preliminary results of this study show that by using Cole-based analysis on EBIS measurements and analyzing the Cole parameters R0 and R∞, it is possible to detect changes on electrical properties of cerebral tissue after stroke. 

  • 35.
    Ayoglu, Burcu
    et al.
    KTH, Skolan för bioteknologi (BIO), Proteomik och nanobioteknologi.
    Kockum, Ingrid
    Olsson, Tomas
    Nilsson, Peter
    KTH, Skolan för bioteknologi (BIO), Proteomik och nanobioteknologi.
    Anoctamin 2 identified as an autoimmune target in multiple sclerosis2016Inngår i: Multiple Sclerosis, ISSN 1352-4585, E-ISSN 1477-0970, Vol. 22, s. 10-10Artikkel i tidsskrift (Annet vitenskapelig)
  • 36.
    Ayoglu, Burcu
    et al.
    KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Mitsios, N.
    Karolinska Inst, Neurosci, Stockholm, Sweden..
    Kockum, I.
    Karolinska Inst, Clin Neurosci, Stockholm, Sweden..
    Olsson, T.
    Karolinska Inst, Clin Neurosci, Stockholm, Sweden..
    Nilsson, Peter
    KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Anoctamin 2 identified as an autoimmune target in multiple sclerosis2016Inngår i: European Journal of Neurology, ISSN 1351-5101, E-ISSN 1468-1331, Vol. 23, s. 57-57Artikkel i tidsskrift (Annet vitenskapelig)
  • 37. Bak, Z
    et al.
    Abildgård, L
    Lisander, B
    Janerot-Sjöberg, B
    Hälsouniversitetet, Linköping University.
    Transesophageal echocardiographic hemodynamic monitoring during preoperative acute normovolemic hemodilution.2000Inngår i: Anesthesiology, ISSN 0003-3022, E-ISSN 1528-1175, Vol. 92, nr 5, s. 1250-6Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Preoperative acute normovolemic hemodilution may compromise oxygen transport. The aims of our study were to describe the hemodynamic effects of normovolemic hemodilution and to determine its effect on systolic and diastolic cardiac function by multiplane transesophageal echocardiography.

    METHODS: In eight anesthetized patients (aged 13-51 yr) without heart disease, hemoglobin was reduced in steps from 123 +/- 8 (mean +/- SD) to 98 +/- 3 and to 79 +/- 5 g/l. Hemodynamic measurements (intravascular pressures, thermodilution cardiac output, and echocardiographic recordings) were obtained during a stabilization period and at each level of hemodilution. Left ventricular wall motion was monitored continuously, and Doppler variables, annular motion, and changes in ejection fractional area were analyzed off-line.

    RESULTS: During hemodilution, cardiac output by thermodilution increased by 16 +/- 7% and 26 +/- 10%, corresponding well to the increase in cardiac output as measured by Doppler (difference, 0.32 +/- 1.2 l/min). Systemic vascular resistance fell 16 +/- 14% and 23 +/- 9% and pulmonary capillary wedge pressure increased slightly (2 +/- 2 mmHg), whereas other pressures, heart rate, wall motion, and diastolic Doppler variables remained unchanged. Ejection fractional area change increased from 44 +/- 7% to 54 +/- 10% and 60 +/- 9% as a result of reduced end-systolic and increased end-diastolic left ventricular areas.

    CONCLUSIONS: A reduction in hemoglobin to 80 g/l during acute normovolemic hemodilution does not normally compromise systolic or diastolic myocardial function as determined by transesophageal echocardiography. Preload, left ventricular ejection fraction, and cardiac output increase with a concomitant fall in systemic vascular resistance.

  • 38. Bak, Z
    et al.
    Sjöberg, F
    Eriksson, O
    Steinvall, I
    Janerot-Sjöberg, Birgitta
    Department of Clinical Physiology, Heart Centre, Linköping University Hospital, Sweden.
    Cardiac dysfunction after burns2008Inngår i: Burns, ISSN 0305-4179, E-ISSN 1879-1409, Vol. 34, nr 5, s. 603-609Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    OBJECTIVES: Using transoesophageal echocardiography (TEE) we investigated the occurrence, and the association of possible abnormalities of motion of the regional wall of the heart (WMA) or diastolic dysfunction with raised troponin concentrations, or both during fluid resuscitation in patients with severe burns.

    PATIENTS AND METHODS: Ten consecutive adults (aged 36-89 years, two women) with burns exceeding 20% total burned body surface area who needed mechanical ventilation were studied. Their mean Baux index was 92.7, and they were resuscitated according to the Parkland formula. Thirty series of TEE examinations and simultaneous laboratory tests for myocyte damage were done 12, 24, and 36h after the burn.

    RESULTS: Half (n=5) the patients had varying grades of leakage of the marker that correlated with changeable WMA at 12, 24 and 36h after the burn (p< or =0.001, 0.044 and 0.02, respectively). No patient had WMA and normal concentrations of biomarkers or vice versa. The mitral deceleration time was short, but left ventricular filling velocity increased together with stroke volume.

    CONCLUSION: Acute myocardial damage recorded by both echocardiography and leakage of troponin was common, and there was a close correlation between them. This is true also when global systolic function is not deteriorated. The mitral flow Doppler pattern suggested restrictive left ventricular diastolic function.

  • 39. Bak, Z
    et al.
    Sjöberg, F
    Rousseau, A
    Steinvall, I
    Janerot-Sjöberg, Birgitta
    Department of Clinical Physiology, Heart Center, Linköping University Hospital.
    Human cardiovascular dose-response to supplemental oxygen2007Inngår i: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 191, nr 1, s. 15-24Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    AIM: The aim of the study was to examine the central and peripheral cardiovascular adaptation and its coupling during increasing levels of hyperoxaemia. We hypothesized a dose-related effect of hyperoxaemia on left ventricular performance and the vascular properties of the arterial tree.

    METHODS: Oscillometrically calibrated arterial subclavian pulse trace data were combined with echocardiographic recordings to obtain non-invasive estimates of left ventricular volumes, aortic root pressure and flow data. For complementary vascular parameters and control purposes whole-body impedance cardiography was applied. In nine (seven males) supine, resting healthy volunteers, aged 23-48 years, data was collected after 15 min of air breathing and at increasing transcutaneous oxygen tensions (20, 40 and 60 kPa), accomplished by a two group, random order and blinded hyperoxemic protocol.

    RESULTS: Left ventricular stroke volume [86 +/- 13 to 75 +/- 9 mL (mean +/- SD)] and end-diastolic area (19.3 +/- 4.4 to 16.8 +/- 4.3 cm(2)) declined (P < 0.05), and showed a linear, negative dose-response relationship to increasing arterial oxygen levels in a regression model. Peripheral resistance and characteristic impedance increased in a similar manner. Heart rate, left ventricular fractional area change, end-systolic area, mean arterial pressure, arterial compliance or carbon dioxide levels did not change.

    CONCLUSION: There is a linear dose-response relationship between arterial oxygen and cardiovascular parameters when the systemic oxygen tension increases above normal. A direct effect of supplemental oxygen on the vessels may therefore not be excluded. Proximal aortic and peripheral resistance increases from hyperoxaemia, but a decrease of venous return implies extra cardiac blood-pooling and compensatory relaxation of the capacitance vessels.

  • 40. Bak, Zoltan
    et al.
    Sjöberg, Folke
    Hälsouniversitetet, Linköping University.
    Eriksson, Olle
    Steinvall, Ingrid
    Janerot-Sjoberg, Birgitta
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik.
    Hemodynamic changes during resuscitation after burns using the Parkland formula2009Inngår i: Journal of Trauma, ISSN 0022-5282, E-ISSN 1529-8809, Vol. 66, nr 2, s. 329-336Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: The Parkland formula (2-4 mL/kg/burned area of total body surface area %) with urine output and mean arterial pressure (MAP) as endpoints for the fluid resuscitation in burns is recommended all over the world. There has recently been a discussion on whether central circulatory endpoints should be used instead, and also whether volumes of fluid should be larger. Despite this, there are few central hemodynamic data available in the literature about the results when the formula is used correctly.

    METHODS: Ten burned patients, admitted to our unit early, and with a burned area of >20% of total body surface area were investigated at 12, 24, and 36 hours after injury. Using transesophageal echocardiography, pulmonary artery catheterization, and transpulmonary thermodilution to monitor them, we evaluated the cardiovascular coupling when urinary output and MAP were used as endpoints.

    RESULTS: Oxygen transport variables, heart rate, MAP, and left ventricular fractional area, did not change significantly during fluid resuscitation. Left ventricular end-systolic and end-diastolic area and global end-diastolic volume index increased from subnormal values at 12 hours to normal ranges at 24 hours after the burn. Extravascular lung water: intrathoracal blood volume ratio was increased 12 hours after the burn.

    CONCLUSIONS: Preload variables, global systolic function, and oxygen transport recorded simultaneously by three separate methods showed no need to increase the total fluid volume within 36 hours of a major burn. Early (12 hours) signs of central circulatory hypovolemia, however, support more rapid infusion of fluid at the beginning of treatment.

  • 41.
    Ban, Yifang
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Fredman, David
    Jonsson, Martin
    Svensson, Leif
    Multi-Criteria Evaluations for Improved Placement of Defibrillators: Preliminary Results2013Inngår i: Circulation, ISSN 0009-7322, E-ISSN 1524-4539, Vol. 128, nr 22, s. 78-Artikkel i tidsskrift (Annet vitenskapelig)
  • 42. Baptista La, Filipa Martins
    et al.
    Sundberg, Johan
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Pregnancy and the Singing Voice: Reports From a Case Study2012Inngår i: Journal of Voice, ISSN 0892-1997, E-ISSN 1873-4588, Vol. 26, nr 4, s. 431-439Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Objectives. Significant changes in body tissues occur during pregnancy; however, literature concerning the effects of pregnancy on the voice is sparse, especially concerning the professional classically trained voice. Hypotheses. Hormonal variations and associated bodily changes during pregnancy affect phonatory conditions, such as vocal fold motility and glottal adduction. Design. Longitudinal case study with a semiprofessional classically trained singer. Methods. Audio, electrolaryngograph, oral pressure, and air flow signals were recorded once a week during the last 12 weeks of pregnancy, 48 hours after birth and during the following consecutive 11 weeks. Vocal tasks included diminuendo sequences of the syllable /pae/sung at various pitches, and performing a Lied. Phonation threshold pressures (PTPs) and collision threshold pressures (CTPs), normalized amplitude quotient (NAQ), alpha ratio, and the dominance of the voice source fundamental were determined. Concentrations of sex female steroid hormones were measured on three occasions. A listening test of timbral brightness and vocal fatigue was carried out. Results. Results demonstrated significantly elevated concentrations of estrogen and progesterone during pregnancy, which were considerably reduced after birth. During pregnancy, CTPs and PTPs were high; and NAQ, alpha ratio, and dominance of the voice source fundamental suggested elevated glottal adduction. In addition, a perceptible decrease of vocal brightness was noted. Conclusions. The elevated CTPs and PTPs during pregnancy suggest reduced vocal fold motility and increased glottal adduction. These changes are compatible with expected effects of elevated concentrations of estrogen and progesterone on tissue viscosity and water retention.

  • 43. Bartonek, A.
    et al.
    Lidbeck, C. M.
    Gutierrez-Farewik, Elena
    KTH, Skolan för teknikvetenskap (SCI), Mekanik, Biomekanik.
    Influence of external visual focus on gait in children with bilateral cerebral palsy2016Inngår i: Pediatric Physical Therapy, ISSN 0898-5669, E-ISSN 1538-005X, Vol. 28, nr 4, s. 393-399Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: To explore whether focusing a target influenced gait in children with cerebral palsy (CP) and typical development (TD). Methods: Thirty children with bilateral CP (Gross Motor Function Classification System [GMFCS] I-III) and 22 with TD looked at a light at walkway end (Gaze Target) while walking and returned (No Target). Results: During Gaze versus No Target, children with TD reduced temporal-spatial parameters and movements in the sagittal (SPM) and transverse planes. In comparison, during Gaze Target, children in CP1 (GMFCS I) had larger trunk SPM, children in CP2 (GMFCS II) larger neck (SPM), and children in CP3 (GMFCS III) greater head and neck frontal plane movements, and reduced cadence and single support. Conclusions: Focusing a target altered gait in children with CP. Children in CP1 reduced movements similar to children with TD, children in CP2 behaved nearly unchanged, whereas children in CP3 reduced movements and temporalspatial parameters, potentially as a consequence of lack of sensory information from lower limbs.

  • 44. Baskaran, Karthikeyan
    et al.
    Rosén, Robert
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Lewis, Peter
    Unsbo, Peter
    Gustafsson, Jörgen
    Benefit of Adaptive Optics Aberration Correction at Preferred Retinal Locus2012Inngår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 89, nr 9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: To investigate the effect of eccentric refractive correction and full aberration correction on both high and low contrast grating resolution at the preferred retinal locus (PRL) of a single low vision subject with a longstanding central scotoma.

    Methods: The subject was a 68 year-old female with bilateral absolute central scotoma due to Stargardt’s disease. She has developed a single PRL located 25° nasally of the damaged macula in her left eye, this being the better of the two eyes. High- (100%) and low contrast (25% & 10%) grating resolution acuity was evaluated using four different correction conditions. The first two corrections were solely refractive error corrections; namely habitual spectacle correction and full sphero-cylindrical correction. The latter two corrections were two versions of adaptive optics corrections of all aberrations; namely full sphero-cylindrical refractive correction with additional aberration correction and habitual spectacle correction with aberration correction.

    Results: The mean high contrast (100%) resolution acuity with her habitual correction was 1.06 logMAR, which improved to 1.00 logMAR with full sphero-cylindrical correction. Under the same conditions, low contrast (25%) acuity improved from 1.30 logMAR to 1.14 logMAR. With adaptive optics aberration correction, the high contrast resolution acuities improved to 0.92/0.89 logMAR and the low contrast acuities, to 1.06/1.04 logMAR under both correction modalities. The low contrast (10%) resolution acuity was 1.34 logMAR with adaptive optics aberration correction; however, with purely refractive error corrections she was unable to identify the orientation of the gratings.

    Conclusion: Correction of all aberrations using adaptive optics improves both high and low contrast resolution acuity at the PRL of a single low vision subject with longstanding absolute central scotoma.

  • 45. Baskaran, Karthikeyan
    et al.
    Unsbo, Peter
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Gustafsson, Jörgen
    Influence of Age on Peripheral Ocular Aberrations2011Inngår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 88, nr 9, s. 1088-1098Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose. To compare peripheral lower and higher order aberrations across the horizontal (+/- 40 degrees) and inferior (-20 degrees) visual fields in healthy groups of young and old emmetropes. Methods. We have measured off-axis aberrations in the groups of 30 younger (24 +/- 3 years) and 30 older (58 +/- 5 years) emmetropes. The aberrations of OD were measured using the COAS-HD VR Shack-Hartmann aberrometer in 10 degrees steps to +/- 40 degrees horizontally and -20 degrees inferiorly in the visual field. The aberrations were quantified with Zernike polynomials for a 4 mm pupil diameter. The second-order aberration coefficients were converted to their respective refraction components (M, J(45), and J(180)). Mixed between-within subjects, analysis of variance were used to determine whether there were significant differences in the refraction and aberration components for the between-subjects variable age and the within-subjects variable eccentricity. Results. Peripheral refraction components were similar in both age groups. Among the higher order coefficients, horizontal coma (C(3)(1)) and spherical aberration (C(4)(0)) varied mostly between the groups. Coma increased linearly with eccentricity, at a more rapid rate in the older group than in the younger group. Spherical aberration was more positive in the older group compared with the younger group. Higher order root mean square increased more rapidly with eccentricity in the older group. Conclusions. Like the axial higher order aberrations, the peripheral higher order aberrations of emmetropes increase with age, particularly coma and spherical aberration.

  • 46.
    Batool, Nazre
    KTH, Skolan för teknik och hälsa (STH).
    Detection and Spatial Analysis of Hepatic Steatosis in Histopathology Images using Sparse Linear Models2016Inngår i: 2016 SIXTH INTERNATIONAL CONFERENCE ON IMAGE PROCESSING THEORY, TOOLS AND APPLICATIONS (IPTA), IEEE, 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Hepatic steatosis is a defining feature of nonalcoholic fatty liver disease, emerging with the increasing incidence of obesity and metabolic syndrome. The research in image-based analysis of hepatic steatosis mostly focuses on the quantification of fat in biopsy images. This work furthers the image-based analysis of hepatic steatosis by exploring the spatial characteristics of fat globules in whole slide biopsy images after performing fat detection. An algorithm based on morphological filtering and sparse linear models is presented for fat detection. Then the spatial properties of detected fat globules in relation to the hepatic anatomical structures of central veins and portal tracts are explored. The test dataset consists of 38 high resolution images from 21 patients. The experimental results provide an insight into the size distributions of fat globules and their location with respect to the anatomical structures.

  • 47.
    Bauer, Margit
    et al.
    Med Univ Graz, Dept Obstet & Gynecol, Graz, Austria..
    Mazza, Edoardo
    Swiss Fed Inst Technol, Dept Mech & Proc Engn, Zurich, Switzerland..
    Jabareen, Mahmood
    Swiss Fed Inst Technol, Dept Mech & Proc Engn, Zurich, Switzerland..
    Sultan, Leila
    Univ Zurich Hosp, Dept Obstet & Gynecol, CH-8091 Zurich, Switzerland..
    Bajka, Michael
    Univ Zurich Hosp, Dept Obstet & Gynecol, CH-8091 Zurich, Switzerland..
    Lang, Uwe
    Med Univ Graz, Dept Obstet & Gynecol, Graz, Austria..
    Zimmermann, Roland
    Univ Zurich Hosp, Dept Obstet & Gynecol, CH-8091 Zurich, Switzerland..
    Holzapfel, Gerhard A.
    KTH, Skolan för elektro- och systemteknik (EES).
    In Vivo Biomechanical Testing of the Human Uterine Cervix in Pregnancy Using an Aspiration Device2009Inngår i: Reproductive Sciences, ISSN 1933-7191, E-ISSN 1933-7205, Vol. 16, nr 3, s. 197A-197AArtikkel i tidsskrift (Annet vitenskapelig)
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    Baxter, Brent S.
    et al.
    University of Utah.
    Hitchner, Lewis E.
    University of Utah.
    Maguire Jr., Gerald Q.
    Columbia University.
    A standard format for digital image exchange1982Bok (Annet vitenskapelig)
  • 49.
    Baxter, Brent S.
    et al.
    University of Utah.
    Zeleznik, Michael P.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    What Types of Standards would be useful in PACS Activities1983Inngår i: Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0361-0748, Vol. 418, s. 146-150Artikkel i tidsskrift (Fagfellevurdert)
  • 50.
    Beckman, Claes
    University of Waterloo.
    The influence of increased interocular lightscatter on the contrast in a confocal scanning laserophthalmoscope image1995Inngår i: Vision Science and Its Application, Vol. 1 of 1995 OSA Technical Digest Series (Optical Society of America, 1995) / [ed] Optical Society of America, Washington, 1995, Vol. 1, s. 106-109Konferansepaper (Fagfellevurdert)
    Abstract [en]

    the influence of increased intraocular light scatter on image quality in a confocal scanning laserophthalmoscope (CSLO) is quntified through computer simulations and model eye experiments.

    Fulltekst (pdf)
    fulltext
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