| 1. |
- Kvarnung, Malin, et al.
(author)
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Ataxia in Patients With Bi-Allelic NFASC Mutations and Absence of Full-Length NF186
- 2019
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In: Frontiers in Genetics. - : Frontiers Media SA. - 1664-8021. ; 10
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Journal article (peer-reviewed)abstract
- The etiology of hereditary ataxia syndromes is heterogeneous, and the mechanisms underlying these disorders are often unknown. Here, we utilized exome sequencing in two siblings with progressive ataxia and muscular weakness and identified a novel homozygous splice mutation (c.3020-1G > A) in neurofascin (NFASC). In RNA extracted from fibroblasts, we showed that the mutation resulted in inframe skipping of exon 26, with a deprived expression of the full-length transcript that corresponds to NFASC isoform NF186. To further investigate the disease mechanisms, we reprogrammed fibroblasts from one affected sibling to induced pluripotent stem cells, directed them to neuroepithelial stem cells and finally differentiated to neurons. In early neurogenesis, differentiating cells with selective depletion of the NF186 isoform showed significantly reduced neurite outgrowth as well as fewer emerging neurites. Furthermore, whole-cell patch-clamp recordings of patient-derived neuronal cells revealed a lower threshold for openings, indicating altered Na+ channel kinetics, suggesting a lower threshold for openings as compared to neuronal cells without the NFASC mutation. Taken together, our results suggest that loss of the full-length NFASC isoform NF186 causes perturbed neurogenesis and impaired neuronal biophysical properties resulting in a novel early-onset autosomal recessive ataxia syndrome.
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| 2. |
- Nilsson, Anna-Malin, 1972, et al.
(author)
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A conjugated diene identified as a prohapten: contact allergenic activity and chemical reactivity of proposed epoxide metabolites.
- 2005
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In: Chemical research in toxicology. - : American Chemical Society (ACS). - 0893-228X .- 1520-5010. ; 18:2, s. 308-16
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Journal article (peer-reviewed)abstract
- A hapten causing allergic contact dermatitis binds covalently to macromolecules via nucleophilic-electrophilic reactions or radical couplings. A prohapten can be seen as a chemically inert compound without electrophilic or radical forming properties. To exert its activity, the prohapten is activated, for example, metabolically, to the hapten. We have investigated the contact allergenic properties of a diene, (5R)-5-isopropenyl-2-methyl-1-methylene-2-cyclohexene (1), as a potential prohapten, and we found it to be a sensitizer in animal studies. The activity is likely to be exerted via epoxide metabolites. Thus, two potential metabolites of the investigated diene, (4S)-1,2-epoxy-4-isopropenyl-1-methyl-6-methylene-cyclohexane (3) and (7R)-7-isopropenyl-4-methyl-1-oxa-spiro[2.5]oct-4-ene (4), were synthesized and subjected to animal tests. Both epoxides were sensitizers. They also elicited significant reactions when tested in animals induced with 1, which indicates that they are formed from the diene in the skin. Furthermore, incubation of 1 with human liver microsomes produced both epoxides. The chemical reactivity of 1, 3, and 4 was investigated in relation to a hexapeptide, H-Pro-His-Cys-Lys-Arg-Met-OH. No adducts were obtained from reactions between the peptide and 1. However, epoxide 3 bound covalently to the cysteine residue and epoxide 4 to both the cysteine and proline residues. Since it is possible to relate the sensitizing capacity of a compound to its key physicochemical properties, knowledge-based expert systems have been developed to predict the toxicity of novel compounds by comparing the structure with activity data stored in the computer database. A diene related to 1 found in the knowledge-based expert system DEREK was considered as a nonsensitizer by this system. Our study indicates that conjugated dienes can be metabolized to contact allergens in the skin. Thus, when constructing predictive test methods based on SARs, it is important to analyze not only the virtual chemical structure of a compound but also its ability to act as a prohapten.
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| 3. |
- Nilsson, Anna-Malin, 1972, et al.
(author)
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An alpha,beta-unsaturated oxime identified as a strong contact allergen. Indications of antigen formation via several pathways.
- 2005
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In: Food and chemical toxicology. - : Elsevier BV. - 0278-6915. ; 43:11, s. 1627-1636
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Journal article (peer-reviewed)abstract
- The aim of this study was to examine the possible skin sensitizing effect of oximes, employing an alpha,beta-unsaturated oxime as the model compound. Oximes are not frequently used as biologically active compounds. However, they have been shown to possess both anti-inflammatory and anti-allergic activities. Furthermore, in a recent study, a number of oximes and oxime-ethers of hydroxylated benzaldehydes and acetophenones were found to be powerful antioxidants suggested to be used in consumer products such as cosmetics and food. Although there are only few reports on the sensitizing effect of oximes, their ability to be hydrolyzed to the corresponding ketones or aldehydes makes them potential contact allergens. The oxime investigated in this study was demonstrated to be a strong contact allergen in both mice and guinea pigs, capable of sensitize the control animals after only one dermal exposure. In order to elucidate the mechanisms for the formation of the complete antigen, a variety of analogues with different reactivity were tested. The results indicate that alpha,beta-unsaturated oximes can react with proteins via several different pathways. Most likely, a metabolic transformation is involved. Due to the strong allergenic effect of the oxime investigated, we strongly advise against the use of such oximes in consumer products until a better understanding of their interactions with biological macromolecules has been obtained.
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| 4. |
- Nilsson, Anna-Malin, 1972, et al.
(author)
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Inhibition of the sensitizing effect of carvone by the addition of non-allergenic compounds.
- 2004
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In: Acta dermato-venereologica. - : Medical Journals Sweden AB. - 0001-5555. ; 84:2, s. 99-105
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Journal article (peer-reviewed)abstract
- We have previously reported a reduction of sensitization to carvone in guinea pigs when adding non-allergenic, structurally related compounds simultaneously at induction. This study investigates the criteria needed to obtain a reduction of sensitization in contact allergy. Linalool, a non-sensitizer structurally unrelated to carvone, significantly reduced the sensitizing capacity of carvone in guinea pigs. The effect of different concentrations of inhibitors in mixtures with carvone was investigated. No significant differences in response were obtained between the concentrations explored. A possible anti-inflammatory effect from the inhibitory chemicals was investigated in vitro. No suppression of the immune system was seen. This study shows that a non-allergenic compound with a structure not resembling the hapten can reduce the sensitizing effect of the hapten. It indicates that reduction of an allergenic effect might occur in consumer products that are mixtures of different chemicals. Further studies with chemically unrelated compounds with and without allergenic effect are needed.
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| 5. |
- Svensson, Mattias, 1982, et al.
(author)
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Fms-like tyrosine kinase 3 ligand controls formation of regulatory T cells in autoimmune arthritis.
- 2013
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In: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 8:1
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Journal article (peer-reviewed)abstract
- Fms-like tyrosine kinase 3 ligand (Flt3L) is known as the primary differentiation and survival factor for dendritic cells (DCs). Furthermore, Flt3L is involved in the homeostatic feedback loop between DCs and regulatory T cell (Treg). We have previously shown that Flt3L accumulates in the synovial fluid in rheumatoid arthritis (RA) and that local exposure to Flt3L aggravates arthritis in mice, suggesting a possible involvement in RA pathogenesis. In the present study we investigated the role of Flt3L on DC populations, Tregs as well as inflammatory responses in experimental antigen-induced arthritis. Arthritis was induced in mBSA-immunized mice by local knee injection of mBSA and Flt3L was provided by daily intraperitoneal injections. Flow cytometry analysis of spleen and lymph nodes revealed an increased formation of DCs and subsequently Tregs in mice treated with Flt3L. Flt3L-treatment was also associated with a reduced production of mBSA specific antibodies and reduced levels of the pro-inflammatory cytokines IL-6 and TNF-α. Morphological evaluation of mBSA injected joints revealed reduced joint destruction in Flt3L treated mice. The role of DCs in mBSA arthritis was further challenged in an adoptive transfer experiment. Transfer of DCs in combination with T-cells from mBSA immunized mice, predisposed naïve recipients for arthritis and production of mBSA specific antibodies. We provide experimental evidence that Flt3L has potent immunoregulatory properties. Flt3L facilitates formation of Treg cells and by this mechanism reduces severity of antigen-induced arthritis in mice. We suggest that high systemic levels of Flt3L have potential to modulate autoreactivity and autoimmunity.
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| 6. |
- Engström, Jens, et al.
(author)
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Energy absorption from parks of point-absorbing wave energy converters in the Swedish exclusive economic zone
- 2020
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In: Energy Science & Engineering. - : John Wiley & Sons. - 2050-0505. ; 8:1, s. 38-49
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Journal article (peer-reviewed)abstract
- In a future energy system based on renewable energy sources, wave energy will most likely play a role due to its high energy potential and low intermittency. The power production from parks of wave energy converters of point absorber type has been extensively studied. This is also the case for the wave energy resource at many coastal areas around the globe. Wave energy has not yet reached a commercial level, and a large variety of technologies exist; therefore, an established method to calculate the technical potential for wave energy has still not been established. To estimate the technical potential of wave energy conversion, some approximations inevitably need to be taken due to the systems high complexity. In this study, a detailed mapping of the wave climate and simulation of large arrays of hydrodynamically cross‐coupled wave energy converters are combined to calculate the technical potential for wave energy conversion in the Swedish exclusive economic zone. A 16‐year wave data set distributed in a 1.1 km × 1.1 km grid is used to calculate the absorbed energy from a park of 200 generic point absorbers. The areas with best potential have an average annual energy absorption of 16 GWh for the selected wave energy park adapted to 1 km2 when using a constant damping, while the theoretical upper bound is 63 GWh for the same area.
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| 7. |
- Jenholt Nolbris, Margaretha, 1956, et al.
(author)
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Young children’s voices in an unlocked Sweden during the COVID-19 pandemic
- 2022
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In: Scandinavian Journal of Public Health. - : Sage Publications. - 1403-4948 .- 1651-1905. ; 50:6, s. 693-702
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Journal article (peer-reviewed)abstract
- Aims: During the COVID-19 pandemic, Sweden was one of the few countries that rejected lockdowns in favour of recommendations for restrictions, including careful hand hygiene and social distancing. Preschools and primary schools remained open. Several studies have shown negative impacts of the pandemic on children, particularly high levels of anxiety. The study aim was to explore how Swedish school-aged children aged 6–14 years, experienced the COVID-19 pandemic and their perceived anxiety.Methods: In total, 774 children aged 6–14 years and their guardians answered an online questionnaire containing 24 questions, along with two instruments measuring anxiety: the Children’s Anxiety Questionnaire and the Numerical Rating Scale. A convergent parallel mixed-methods design was used for analysing the quantitative and qualitative data. Each data source was first analysed separately, followed by a merged interpretative analysis.Results: The results showed generally low levels of anxiety, with no significant sex differences. Children who refrained from normal social activities or group activities (n=377) had significantly higher levels of anxiety. Most of the children were able to appreciate the bright side of life, despite the social distancing and refraining from activities, which prevented them from meeting and hugging their loved ones.Conclusions: These Swedish children generally experienced low levels of anxiety, except those who refrained from social activities. Life was nonetheless mostly experienced as normal, largely because schools remained open. Keeping life as normal as possible could be one important factor in preventing higher anxiety and depression levels in children during a pandemic.
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| 8. |
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| 9. |
- Nilsson, Stefan, 1972, et al.
(author)
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Children's and adolescents' experiences of living with cancer
- 2021
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In: Nursing children and young people. - : RCN Publishing Ltd.. - 2046-2336 .- 2046-2344. ; 33:3, s. 10-16
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Journal article (peer-reviewed)abstract
- Background All healthcare professionals working with children should have a child-centred perspective, and should be responsive to children and adolescents who want to talk about their thoughts and feelings. The child's or adolescent's story is the starting point for mutual understanding between them and the healthcare professional, and is the basis for shared decision-making between patients and healthcare professionals in child-centred care. Aim To advance understanding of how Swedish children and adolescents with cancer perceived the effects of the disease and its treatment on their everyday life. Method Ten girls and five boys, aged between five and 18 years, with cancer were interviewed individually using four communication tools. The interviews lasted between 20 and 65 minutes and took place without their parents present. The data were analysed using content analysis. Findings Transition to an unpredictable everyday life was identified as a main theme, with five subthemes: struggling with side effects of the cancer and its treatment; treatment as an 'emotional rollercoaster'; changed self and being vulnerable; changed social life; and concerns about academic achievement. Conclusion To provide effective support and care for children and adolescents with cancer, healthcare professionals should strive to listen to them and focus on their perspectives.
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| 10. |
- Nilsson, Stefan, 1972, et al.
(author)
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To be or not to be vaccinated against COVID-19 - The adolescents' perspective - A mixed-methods study in Sweden.
- 2021
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In: Vaccine: X. - : Elsevier BV. - 2590-1362. ; 9
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Journal article (peer-reviewed)abstract
- Vaccination of the population seems to be an important strategy in halting the COVID-19 pandemic in both local and global society. The aim of this study was to explore Swedish adolescents' willingness to be vaccinated against COVID-19 and its association with sociodemographic and other possible factors. A survey was distributed in Sweden between 7 July and 8 November 2020. The main qualitative question concerned adolescents' thoughts on vaccination against COVID-19 and evaluated whether the adolescents would like to be vaccinated when a COVID-19 vaccine is made available. In total, 702 adolescents aged between 15 and 19 responded to the questionnaire. A convergent parallel mixed-methods design was used. The results showed that nearly one in three adolescents had not decided if they wanted to get a COVID-19 vaccine, i.e. 30.5%: n = 214. Of the participants 54.3% (n = 381) were willing to be vaccinated. Girls had higher levels of anxiety about the vaccine compared to boys. In addition, high levels of anxiety impacted on the participants' willingness to be vaccinated. One reason for being undecided about the vaccine was that participants felt they did not know enough about it. Practising social distancing increased willingness to be vaccinated, as reflected in the qualitative results which showed participants wanted to be vaccinated to protect others. The results impart important knowledge to healthcare professionals and contribute to their communication with adolescents about vaccine hesitancy.
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