11. |
- Maria Psonka-Antonczyk, Katarzyna, et al.
(author)
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Nanoscopic and Photonic Ultrastructural Characterization of Two Distinct Insulin Amyloid States
- 2012
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In: International Journal of Molecular Sciences. - : MDPI AG, POSTFACH, CH-4005 BASEL, SWITZERLAND. - 1661-6596 .- 1422-0067. ; 13:2, s. 1461-1480
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Journal article (peer-reviewed)abstract
- Two different conformational isoforms or amyloid strains of insulin with different cytotoxic capacity have been described previously. Herein these filamentous and fibrillar amyloid states of insulin were investigated using biophysical and spectroscopic techniques in combination with luminescent conjugated oligothiophenes (LCO). This new class of fluorescent probes has a well defined molecular structure with a distinct number of thiophene units that can adopt different dihedral angles depending on its binding site to an amyloid structure. Based on data from surface charge, hydrophobicity, fluorescence spectroscopy and imaging, along with atomic force microscopy (AFM), we deduce the ultrastructure and fluorescent properties of LCO stained insulin fibrils and filaments. Combined total internal reflection fluorescence microscopy (TIRFM) and AFM revealed rigid linear fibrous assemblies of fibrils whereas filaments showed a short curvilinear morphology which assemble into cloudy deposits. All studied LCOs bound to the filaments afforded more blue-shifted excitation and emission spectra in contrast to those corresponding to the fibril indicating a different LCO binding site, which was also supported by less efficient hydrophobic probe binding. Taken together, the multi-tool approach used here indicates the power of ultrastructure identification applying AFM together with LCO fluorescence interrogation, including TIRFM, to resolve structural differences between amyloid states.
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12. |
- Nilsson, Anna-Lena, et al.
(author)
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Relationship between Ljungan virus antibodies, HLA-DQ8, and insulin autoantibodies in newly diagnosed type 1 diabetes children
- 2013
-
In: Viral immunology. - : Mary Ann Liebert, Inc.. - 0882-8245 .- 1557-8976. ; 26:3, s. 207-215
-
Journal article (peer-reviewed)abstract
- Environmental factors, including viral infections, may explain an increasing and fluctuating incidence of childhood type 1 diabetes (T1D). Ljungan virus (LV) isolated from bank voles have been implicated, but it is unclear whether LV contributes to islet autoimmunity, progression to clinical onset, or both, of T1D. The aim was to test whether LV antibodies (LVAb) were related to HLA-DQ and islet autoantibodies in newly diagnosed T1D patients (n = 676) and controls (n = 309). Patients, 0-18 years of age, diagnosed with T1D in 1996-2005 were analyzed for LVAb, HLA-DQ genotypes, and all seven known islet autoantibodies (GADA, IA-2A, IAA, ICA, ZnT8RA, ZnT8WA, and ZnT8QA). LVAb at 75th percentile, defined as cut off, was 90 (range 6-3936) U/mL and 4th quartile LVAb were found in 25% (170/676) of which 64% were < 10 (n = 108, p < 0.0001), and 27% were < 5 (n = 45; p < 0.0001) years old. The 4th quartile LVAb in children < 10 years of age correlated to HLA DQ2/8, 8/8, and 8/X (p < 0.0001). Furthermore, in the group with 4th quartile LVAb, 55% were IAA positive (p = 0.01) and correlation was found between 4th quartile LVAb and IAA in children < 10 years of age (p = 0.035). It is concluded that 1) LVAb were common among the young T1D patients and LVAb levels were higher in the younger age groups; 2) 4th quartile LVAb correlated with IAA; and 3) there was a correlation between 4th quartile LVAb and HLA-DQ8, particularly in the young patients. The presence of LVAb supports the notion that prior exposure to LV may be associated with T1D.
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13. |
- Nilsson, Anna-Lena, et al.
(author)
-
Relationship Between Ljungan Virus Antibodies, HLA-DQ8, and Insulin Autoantibodies in Newly Diagnosed Type 1 Diabetes Children
- 2013
-
In: Viral Immunology. - : Mary Ann Liebert Inc. - 0882-8245 .- 1557-8976. ; 26:3, s. 207-215
-
Journal article (peer-reviewed)abstract
- Environmental factors, including viral infections, may explain an increasing and fluctuating incidence of childhood type 1 diabetes (T1D). Ljungan virus (LV) isolated from bank voles have been implicated, but it is unclear whether LV contributes to islet autoimmunity, progression to clinical onset, or both, of T1D. The aim was to test whether LV antibodies (LVAb) were related to HLA-DQ and islet autoantibodies in newly diagnosed T1D patients (n = 676) and controls (n = 309). Patients, 0-18 years of age, diagnosed with T1D in 1996-2005 were analyzed for LVAb, HLA-DQ genotypes, and all seven known islet autoantibodies (GADA, IA-2A, IAA, ICA, ZnT8RA, ZnT8WA, and ZnT8QA). LVAb at 75th percentile, defined as cut off, was 90 (range 6-3936) U/mL and 4th quartile LVAb were found in 25% (170/676) of which 64% were < 10 (n = 108, p < 0.0001), and 27% were < 5 (n = 45; p < 0.0001) years old. The 4th quartile LVAb in children < 10 years of age correlated to HLA DQ2/8, 8/8, and 8/X (p < 0.0001). Furthermore, in the group with 4th quartile LVAb, 55% were IAA positive (p = 0.01) and correlation was found between 4th quartile LVAb and IAA in children < 10 years of age (p = 0.035). It is concluded that 1) LVAb were common among the young T1D patients and LVAb levels were higher in the younger age groups; 2) 4th quartile LVAb correlated with IAA; and 3) there was a correlation between 4th quartile LVAb and HLA-DQ8, particularly in the young patients. The presence of LVAb supports the notion that prior exposure to LV may be associated with T1D.
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14. |
- Nilsson, Susanna, et al.
(author)
-
Cross-Organizational Collaboration Supported by Augmented Reality
- 2011
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In: IEEE Transactions on Visualization and Computer Graphics. - : Institute of Electrical and Electronics Engineers (IEEE). - 1077-2626 .- 1941-0506. ; 17:10, s. 1380-1392
-
Journal article (peer-reviewed)abstract
- This paper presents a study where Augmented Reality (AR) technology has been used as a tool for supporting collaboration between the rescue services, the police and military personnel in a crisis management scenario. There are few studies on how AR systems should be designed to improve cooperation between actors from different organizations while at the same time supporting individual needs. In the present study, an AR system was utilized for supporting joint planning tasks by providing organization specific views of a shared map. The study involved a simulated emergency event conducted in close to real settings with representatives from the organizations for which the system is developed. As a baseline, a series of trials without the AR system was carried out. Results show that the users were positive toward the AR system and would like to use it in real work. They also experience some performance benefits of using the AR system compared to their traditional tools. Finally, the problem of designing for collaborative work as well as the benefits of using an iterative design processes is discussed.
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15. |
- Nilsson, Susanna, et al.
(author)
-
Cross-Organizational Collaboration Supported by Augmented Reality
- 2011
-
In: IEEE Transactions on Visualization and Computer Graphics. - : Institute of Electrical and Electronics Engineers (IEEE). - 1077-2626 .- 1941-0506. ; 17:10, s. 1380-1392
-
Journal article (peer-reviewed)abstract
- This paper presents a study where Augmented Reality (AR) technology has been used as a tool for supporting collaboration between the rescue services, the police and military personnel in a crisis management scenario. There are few studies on how AR systems should be designed to improve cooperation between actors from different organizations while at the same time supporting individual needs. In the present study, an AR system was utilized for supporting joint planning tasks by providing organization specific views of a shared map. The study involved a simulated emergency event conducted in close to real settings with representatives from the organizations for which the system is developed. As a baseline, a series of trials without the AR system was carried out. Results show that the users were positive toward the AR system and would like to use it in real work. They also experience some performance benefits of using the AR system compared to their traditional tools. Finally, the problem of designing for collaborative work as well as the benefits of using an iterative design processes is discussed.
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16. |
- Nyström, Sofie, et al.
(author)
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Evidence for Age-Dependent in Vivo Conformational Rearrangement within A beta Amyloid Deposits
- 2013
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In: ACS Chemical Biology. - : American Chemical Society. - 1554-8929 .- 1554-8937. ; 8:6, s. 1128-1133
-
Journal article (peer-reviewed)abstract
- Deposition of aggregated A beta peptide in the brain is one of the major hallmarks of Alzheimers disease. Using a combination of two structurally different, but related, hypersensitive fluorescent amyloid markers, LCOs, reporting on separate ultrastructural elements, we show that conformational rearrangement occurs within A beta plaques of transgenic mouse models as the animals age. This important mechanistic insight should aid the design and evaluation of experiments currently using plaque load as readout.
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17. |
- Schmidt, Eva, et al.
(author)
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Expression of the Hutchinson-Gilford progeria mutation during osteoblast development results in loss of osteocytes, irregular mineralization, and poor biomechanical properties.
- 2012
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In: The Journal of biological chemistry. - 1083-351X. ; 287:40, s. 33512-33522
-
Journal article (peer-reviewed)abstract
- Hutchinson-Gilford progeria syndrome (HGPS) is a very rare genetic disorder that is characterized by multiple features of premature aging and largely affects tissues of mesenchymal origin. In this study, we describe the development of a tissue-specific mouse model that overexpresses the most common HGPS mutation (LMNA, c.1824C>T, p.G608G) in osteoblasts. Already at the age of 5 weeks, HGPS mutant mice show growth retardation, imbalanced gait and spontaneous fractures. Histopathological examination revealed an irregular bone structure, characterized by widespread loss of osteocytes, defects in mineralization, and a hypocellular red bone marrow. Computerized tomography analysis demonstrated impaired skeletal geometry and altered bone structure. The skeletal defects, which resemble the clinical features reported for bone disease in HGPS patients, was associated with an abnormal osteoblast differentiation. The osteoblast-specific expression of the HGPS mutation increased DNA damage and affected Wnt signaling. In the teeth, irregular dentin formation, as was previously demonstrated in human progeria cases, caused severe dental abnormalities affecting the incisors. The observed phenotype also shows similarities to reported bone abnormalities in aging mice and may therefore help to uncover general principles of the aging process.
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18. |
- van de Ven, Johannes P. H., et al.
(author)
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A functional variant in the CFI gene confers a high risk of age-related macular degeneration
- 2013
-
In: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 45:7, s. 813-813
-
Journal article (peer-reviewed)abstract
- Up to half of the heritability of age-related macular degeneration (AMD) is explained by common variants(1-5). Here, we report the identification of a rare, highly penetrant missense mutation in CFI encoding a p.Gly119Arg substitution that confers high risk of AMD (P = 3.79 x 10(-6); odds ratio (OR) = 22.20, 95% confidence interval (CI) = 2.98-164.49). Plasma and sera from cases carrying the p.Gly119Arg substitution mediated the degradation of C3b, both in the fluid phase and on the cell surface, to a lesser extent than those from controls. Recombinant protein studies showed that the Gly119Arg mutant protein is both expressed and secreted at lower levels than wild-type protein. Consistent with these findings, human CFI mRNA encoding Arg119 had reduced activity compared to wild-type mRNA encoding Gly119 in regulating vessel thickness and branching in the zebrafish retina. Taken together, these findings demonstrate that rare, highly penetrant mutations contribute to the genetic burden of AMD.
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