| 1. |
- Casas, Rosaura, 1954-, et al.
(författare)
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Impaired maturation of monocyte-derived dendritic cells from birch allergic individuals in association with birch-specific immune responses
- 2007
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Ingår i: Scandinavian Journal of Immunology. - : Wiley. - 0300-9475 .- 1365-3083. ; 66:5, s. 591-598
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Tidskriftsartikel (refereegranskat)abstract
- Optimal activation of T lymphocytes requires a costimulatory signal provided by the interaction of molecules on the surface of T cells with their ligands expressed on dendritic cells (DC). We investigated whether DC differentiated from monocytes from healthy and birch allergic asthmatic individuals and further maturated by stimulation with cat and birch allergens and LPS differ in their phenotypic receptor expression. Similar expression of DC surface markers, including HLA-DR, CD80, CD86, CD83, CD1a and CD11c, was detected in monocyte-derived DC from allergic and healthy individuals. Cells from healthy donors stimulated either antigen showed a similar activation of the CD80 and double CD80/CD86 costimulatory molecules when compared with non-stimulated cells. In the case of cells from allergic individuals, birch allergen was unable to produce the same increased expression of CD80 alone or in combination with CD80/CD86, in comparison with cells stimulated with cat and LPS. Levels of IL-6, IL-8, IL-10, MCP-1/MCAF and MIP-1β were similar in the supernatant of non-stimulated DC from both groups of subjects. By contrast, the spontaneous secretion of IL-12p70 and TNF-α was higher in the supernatant of DC from healthy subjects when compared with that from allergic individuals. Stimulation with birch and LPS resulted in an increased secretion of IL-12p70 in samples from healthy when compared with that in allergic individuals. The results suggest an impaired specific maturation of DC from birch allergic individuals in association with birch-specific immune responses. Lower secretion of IL-12p70 from birch-stimulated DC from allergic individuals suggests that not only maturation, but also the specific Th1 function of these cells seems to be affected in those individuals.
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| 2. |
- Lundberg, Anna, 1977-
(författare)
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Immune responses to lipopolysaccharide in relation to allergic disease : a TLR4 gene polymorphism and endotoxin exposure
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Allergic diseases have increased during the last decades, particularly in affluent countries, possibly due to a reduced and/or altered microbial exposure during infancy. Activation of the immune system by microbes early in life is probably required for accurate maturation of the immune system and tolerance development. It is not fully understood how microbial exposure is associated with the development of allergic diseases, however. Genetic factors may influence microbial induced immune responses. A certain polymorphism, in the gene coding for the Toll-like receptor 4, i.e. (TLR4 Asp299Gly), has been suggested to alter the immunological responsiveness to bacterial lipopolysaccharide (LPS).Aim: The aim of this thesis was to study the interplay between LPS induced immune responses, LPS signalling related genetic polymorphisms, allergic disease and endotoxin exposure.Subjects: The thesis is based on the results obtained from individuals in three different study groups, i.e. Estonian and Swedish children followed prospectively from birth up to five years of age, Swedish school-children eight and 14 years of age and young adults.Methods: The study subjects were clinically evaluated regarding allergic diseases with skin prick tests, circulating IgE levels, validated questionnaires and clinical examinations by paediatricians or research nurses. The gene polymorphisms TLR4 Asp299Gly and CD14/-159 were analysed. Peripheral blood mononuclear cells were isolated from blood and cultured with LPS from two Gram negative bacterial strains, i.e. Salmonella enterica serotype Typhimurium (Serotype Typhimurium) and Escherichia coli (E. coli). Cytokine and chemokine secretions were analysed with Luminex or ELISA technique. Receptor expression of circulating peripheral blood monocytes was analysed with flow cytometry. The phosphorylation of intracellular proteins involved in LPS signalling pathways was analysed with Luminex technique. mRNA expression of proteins involved in LPS signalling pathways and of markers for T regulatory cells were analysed with realtime-PCR.Results: In school-children and young adults, the TLR4 Asp299Gly gene polymorphism was associated with reduced LPS induced IκBα phosphorylation, IL-10 and IL-12 cytokine secretion. Interestingly, these findings were observed only when the cells were cultured with LPS from Serotype Typhimurium but not with LPS from E. coli. The polymorphism was positively associated with asthma, especially atopic asthma.Several differences in immunological responses to LPS were observed between allergic and non-allergic individuals. Asthma in school-children was associated with reduced LPS induced cytokine production of IL-10 and IL-12. The phosphorylation of IκBα was lower in adult allergic compared to non-allergic individuals. Swedish children who had developed allergic disease at five years of age had lower TLR2 mRNA expression at birth compared to children who remained healthy.Estonian children displayed generally lower LPS induced cytokine and chemokine production as compared to Swedish children both at birth and at 3 and 6 months of age. The mRNA expression of the T regulatory associated markers Foxp3 and Ebi3 were higher in the Estonian compared to the Swedish children at birth.Conclusion: Polymorphisms in genes coding for pattern recognition receptors can alter the immune responsiveness of the host to microbial components and may be of importance for the development of asthma. Lower LPS induced cytokine response and higher expression of T regulatory associated markers were seen in children from Estonia as compared to Sweden, suggesting an increased capacity for early immune regulation among infants from a country with a low prevalence of allergic disease.
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| 3. |
- Lundberg, Anna, 1977-, et al.
(författare)
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On the Effect of Variations in paper composition on print quality
- 2009
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Ingår i: International Conference on Digital Printing Technologies 2009. - : The Society for Imaging Science and Technology. - 9780892082872 ; , s. 316-319
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Konferensbidrag (refereegranskat)abstract
- During the last few years, digital printing technology has begun to play a significant role in the printing industry due to the quest for short runs and variable data printing. Digital printing using inkjet technology makes heavy demands on the paper's ability to rapidly absorb liquid and thereby increases the need to understand what parameters that affect the dynamics and interactions between paper and ink and how print quality is affected by these parameters. In this paper, the print quality for nine pilot papers with varying composition and eight different commercial papers has been studied. The printouts have been made with two small office/Home office printers; the print quality measurements for this study have been line quality-measurements and color -gamut volume measurements. The line quality and the color gamut volume for the commercial papers and the pilot papers are discussed.
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| 4. |
- Steenari, Britt-Marie, 1953, et al.
(författare)
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Investigation of Ash Sintering during Combustion of Agricultural Residues and the Effect of Additives
- 2009
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Ingår i: Energy & Fuels. - : American Chemical Society (ACS). - 1520-5029 .- 0887-0624. ; 23:11, s. 5655-5662
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Tidskriftsartikel (refereegranskat)abstract
- In the process of creating sustainable heat and power production systems it is important to find alternative, renewable fuels that are carbon dioxide neutral. Preferably these fuels Should be domestic, thus diminishing the need for transportation. One option could be to Use existing residues from local agriculture and food production. Development of combustion methods suitable for such residues is presently being pursued by a number of companies. Because many biomass fuels have compositions that makes them inclined to cause ash sintering problems and emissions of acid gases, there may be it need for the use of additives to decrease such problems. The aim of this work was to examine the ash characteristics of some agricultural crops and residues and to find mixtures of fuels and additives that can form the basis for production of fuel pellets with minimal problems. The work is focused on biomass fuel pellets for small-scale grate-fired combustors. Three additives (limestone powder, kaolin, and sodium bicarbonate) were investigated regarding their effects oil the ash melting behavior. The results Show that calcium carbonate and kaolin both serve as good additives to prevent the formation of slag. The best antislagging effect was achieved when both additives were used. Sodium bicarbonate can be used as a sulfur binding additive, but this cannot be recommended since it increases the slag formation considerably. The conclusion is that combustion of agricultural crops and residues may be hampered by problems such its slag formation and ash fouling. However, through the use of suitable additives, the ash sintering characteristics can be improved significantly. This means that agricultural residues can be competitive fuels on the energy market in the future.
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| 5. |
- Södergren, Anna, 1977-, et al.
(författare)
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Increased incidence of and impaired prognosis after acute myocardial infarction among patients with seropositive rheumatoid arthritis.
- 2007
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ Publishing Group Ltd & European League Against Rheumatism. - 0003-4967 .- 1468-2060. ; 66:2, s. 263-266
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To examine the incidence and outcome of acute myocardial infarction (AMI) in patients with rheumatoid arthritis compared with the general population, and to examine whether care and treatment of an AMI differs between patients and controls. Methods: The Multinational Monitoring of Trends and Determinants of Cardiovascular Disease register for northern Sweden was used to compare those incidences of AMI in a cohort of patients with rheumatoid arthritis with that in the general population. 35 patients with rheumatoid arthritis who had also experienced an AMI were identified. For each patient with rheumatoid arthritis, three controls with a history of AMI but without rheumatoid arthritis were randomly selected from the same register, and matched for age, sex and year of the AMI for evaluation of case fatality and potential differences in treatment of AMI. Results: The standardised incidence ratio for AMI was 2.9 in patients with rheumatoid arthritis compared with the general population (p<0.05). During the first 10 years after an AMI, patients with rheumatoid arthritis had a higher overall case fatality compared with controls (hazard ratio (HR) 1.67, 95% confidence interval (CI) 1.02 to 2.71). Survival time was decreased in the rheumatoid arthritis group compared with controls despite the same care and treatment. Conclusion: Both the incidence of and case fatality after an AMI were higher among patients with rheumatoid arthritis than among the general population. The results emphasise the necessity of optimising the preventive, diagnostic and caring strategies for AMI in rheumatoid arthritis.
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