| 1. |
- Andersson, Erika, et al.
(författare)
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A contrast variation SANS and SAXS study of soil derived dissolved organic matter, and its interactions with hematite nanoparticles
- 2023
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Ingår i: JCIS Open. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Soil derived dissolved organic matter (DOM) is an important component of the carbon cycle and influences numerous biogeochemical processes, including the formation of mineral-organic associations. DOM ranges in size from small organic molecules to macromolecules and colloidal aggregates. In this study we have used small angle neutron (SANS) and X-ray (SAXS) scattering to characterize the colloidal DOM fraction from the organic layer of a boreal forest soil, and its interactions with hematite (α-Fe2O3) mineral nanoparticles. Comparison between SAXS and contrast variation SANS patterns revealed that the scattering form factor of the colloidal DOM aggregates was essentially independent of the scattering contrast, implying that the colloidal aggregates have an essentially homogeneous chemical composition, down to the nanometre length scale. Variation of the D2O/H2O ratio of the solvent yielded a SANS intensity minimum at ca. 40 vol % D2O, which was consistent with colloids composed of mainly polysaccharides. At pH 5.5 the pure hematite nanoparticles were colloidally stable in water and characterized by a ζ-potential of +25 mV and a hydrodynamic radius of ca. 70 nm. In the presence of DOM, the hematite nanoparticles lost the colloidal stability and aggregated into larger clusters, displaying a negative ζ-potential of ca. −25 mV. The charge reversal suggested that negatively charged polyanions of DOM adsorbed onto the hematite particles, possibly leading to bridging flocculation. Our results suggested that mainly low molecular weight components induced hematite aggregation because no or very limited interactions between DOM colloids and hematite were detected.
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| 2. |
- Andersson, Erika, et al.
(författare)
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Generation and properties of organic colloids extracted by water from the organic horizon of a boreal forest soil
- 2023
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Ingår i: Geoderma. - : Elsevier BV. - 0016-7061. ; 432
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Tidskriftsartikel (refereegranskat)abstract
- Organic colloids are an important part of dissolved organic matter (DOM) yet many of their properties remain elusive. The main aims of this study were to assess how the colloidal properties of DOM extracted with water from an organic boreal soil horizon varied with the extraction protocol, and thereby provide insight into the nature of the DOM colloids and develop a mechanistic understanding of how the colloids were generated from the parent soil aggregates. This was accomplished by systematic variations of extraction temperature (4 °C–100 °C), time, mechanical agitation, and pH, together with a combination of chemical analyses, and light and X-ray scattering. Our results agreed with the previous identification of two main colloidal DOM species, one fractal cluster and a second, smaller colloidal DOM species described as chains or coils. Fractal clusters completely dominated the colloidal DOM in extracts from our soil at room temperature and below. Colloidal coils only existed in DOM extracted above room temperature, and their amount increased significantly between 50 °C–100 °C. Moreover, the temperature variation indicated that the fractal clusters partly dissolved into colloidal coils at elevated temperatures. Mechanical agitation at 4 °C significantly increased the amount of DOM extracted, increasing the concentrations of both fractal clusters and low-molecular weight organic compounds. While the clusters were extracted from agitated and non-agitated soil suspensions, the low molecular weight organics were mainly released by agitation. Based on the experimental observations, we propose a conceptual model where parent soil aggregates contain the fractal clusters in mobile and occluded forms, and that the occluded clusters co-exist with occluded low molecular weight organics. These occluded forms may be released by mechanical forces, increasing pH and temperature. At higher temperatures, the soil aggregates and the fractal clusters start to break up, and subsequently individual colloidal coils, presumably carbohydrates, disperse in the water phase. The model explains the origin and properties of the fractal clusters that completely dominate the colloidal DOM extracted from our soil at room temperature and below.
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| 3. |
- Aybay, Erdem, et al.
(författare)
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Extended cleavage specificities of human granzymes A and K, two closely related enzymes with conserved but still poorly defined functions in T and NK cell-mediated immunity
- 2023
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Ingår i: Frontiers in Immunology. - : Frontiers Media S.A.. - 1664-3224. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Granzymes A and K are two highly homologous serine proteases expressed by mammalian cytotoxic T cells (CTL) and natural killer cells (NK). Granzyme A is the most abundant of the different granzymes (gzms) expressed by these two cell types. Gzms A and K are found in all jawed vertebrates and are the most well conserved of all hematopoietic serine proteases. Their potential functions have been studied extensively for many years, however, without clear conclusions. Gzm A was for many years thought to serve as a key component in the defense against viral infection by the induction of apoptosis in virus-infected cells, similar to gzm B. However, later studies have questioned this role and instead indicated that gzm A may act as a potent inducer of inflammatory cytokines and chemokines. Gzms A and K form clearly separate branches in a phylogenetic tree indicating separate functions. Transcriptional analyses presented here demonstrate the presence of gzm A and K transcripts in both CD4+ and CD8+ T cells. To enable screening for their primary biological targets we have made a detailed analysis of their extended cleavage specificities. Phage display analysis of the cleavage specificity of the recombinant enzymes showed that both gzms A and K are strict tryptases with high selectivity for Arg over Lys in the P1 position. The major differences in the specificities of these two enzymes are located N-terminally of the cleavage site, where gzm A prefers small amino acids such as Gly in the P3 position and shows a relatively relaxed selectivity in the P2 position. In contrast, gzm K prefers large amino acids such as Phe, Tyr, and Trp in both the P2 and P3 positions and does not tolerate negatively charged residues in the P2 position. This major distinction in extended specificities is likely reflected also in preferred in vivo targets of these two enzymes. This information can now be utilized for high-precision screening of primary targets for gzms A and K in search of their highly conserved but still poorly defined functions in vertebrate immunity.
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| 4. |
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| 5. |
- Betancourt, Lazaro Hiram, et al.
(författare)
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The human melanoma proteome atlas-Defining the molecular pathology
- 2021
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Ingår i: Clinical and Translational Medicine. - : Wiley. - 2001-1326. ; 11:7, s. 1-20
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Tidskriftsartikel (refereegranskat)abstract
- The MM500 study is an initiative to map the protein levels in malignant melanoma tumor samples, focused on in-depth histopathology coupled to proteome characterization. The protein levels and localization were determined for a broad spectrum of diverse, surgically isolated melanoma tumors originating from multiple body locations. More than 15,500 proteoforms were identified by mass spectrometry, from which chromosomal and subcellular localization was annotated within both primary and metastatic melanoma. The data generated by global proteomic experiments covered 72% of the proteins identified in the recently reported high stringency blueprint of the human proteome. This study contributes to the NIH Cancer Moonshot initiative combining detailed histopathological presentation with the molecular characterization for 505 melanoma tumor samples, localized in 26 organs from 232 patients.
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| 6. |
- Danielsson, Tatiana
(författare)
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Further Investigations of Convergence Results for Homogenization Problems with Various Combinations of Scales
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is based on six papers. We study the homogenization of selected parabolic problems with one or more microscopic scales in space and time, respectively. The approaches are prepared by means of certain methods, like two-scale convergence, multiscale convergence and also the evolution setting of multiscale convergence and very weak multiscale convergence. Paper I treats a linear parabolic homogenization problem with rapid spatial and temporal oscillations in perforated domains. Suitable results of two-scale convergence type are established. Paper II deals with further development of compactness results which can be used in the homogenization procedure engaging a certain limit condition. The homogenization procedure deals with a parabolic problem with a certain matching between a fast spatial and a fast temporal scale and a coefficient passing to zero that the time derivative is multiplied with. Papers III and IV are further generalizations of Paper II and investigate homogenization problems with different types of matching between the microscopic scales. Papers III and IV deal with one and two rapid scales in both space and time respectively. Paper V treats the nonlinearity of monotone parabolic problems with an arbitrary number of spatial and temporal scales by applying the perturbed test functions method together with multiscale convergence and very weak multiscale convergence adapted to the evolution setting. In Paper VI we discuss the relation between two-scale convergence and the unfolding method and potential extensions of existing results. The papers above are summarized in Chapter 4. Chapter 1 gives a brief introduction to the topic and Chapters 2 and 3 are surveys over some important previous results.
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| 7. |
- Dixon-Suen, Suzanne C, et al.
(författare)
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Physical activity, sedentary time and breast cancer risk : a Mendelian randomisation study
- 2022
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Ingår i: British Journal of Sports Medicine. - : BMJ Publishing Group Ltd. - 0306-3674 .- 1473-0480. ; 56:20, s. 1157-1170
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Physical inactivity and sedentary behaviour are associated with higher breast cancer risk in observational studies, but ascribing causality is difficult. Mendelian randomisation (MR) assesses causality by simulating randomised trial groups using genotype. We assessed whether lifelong physical activity or sedentary time, assessed using genotype, may be causally associated with breast cancer risk overall, pre/post-menopause, and by case-groups defined by tumour characteristics.METHODS: We performed two-sample inverse-variance-weighted MR using individual-level Breast Cancer Association Consortium case-control data from 130 957 European-ancestry women (69 838 invasive cases), and published UK Biobank data (n=91 105-377 234). Genetic instruments were single nucleotide polymorphisms (SNPs) associated in UK Biobank with wrist-worn accelerometer-measured overall physical activity (nsnps=5) or sedentary time (nsnps=6), or accelerometer-measured (nsnps=1) or self-reported (nsnps=5) vigorous physical activity.RESULTS: Greater genetically-predicted overall activity was associated with lower breast cancer overall risk (OR=0.59; 95% confidence interval (CI) 0.42 to 0.83 per-standard deviation (SD;~8 milligravities acceleration)) and for most case-groups. Genetically-predicted vigorous activity was associated with lower risk of pre/perimenopausal breast cancer (OR=0.62; 95% CI 0.45 to 0.87,≥3 vs. 0 self-reported days/week), with consistent estimates for most case-groups. Greater genetically-predicted sedentary time was associated with higher hormone-receptor-negative tumour risk (OR=1.77; 95% CI 1.07 to 2.92 per-SD (~7% time spent sedentary)), with elevated estimates for most case-groups. Results were robust to sensitivity analyses examining pleiotropy (including weighted-median-MR, MR-Egger).CONCLUSION: Our study provides strong evidence that greater overall physical activity, greater vigorous activity, and lower sedentary time are likely to reduce breast cancer risk. More widespread adoption of active lifestyles may reduce the burden from the most common cancer in women.
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| 8. |
- Duque-Salazar, Juan Diego, et al.
(författare)
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Implementing Gender Provisions : A Study of the Comprehensive Agreement on the Bangsamoro in the Philippines
- 2023
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Ingår i: International Negotiation. - : Brill Nijhoff. - 1382-340X .- 1571-8069. ; 28:2, s. 306-337
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Tidskriftsartikel (refereegranskat)abstract
- While scholars on gender provisions have focused on why and how this type of peace agreement clause gets incorporated, few studies have sought to improve our understanding of the implementation process. Addressing this gap empirically, this study utilizes unique interview material to analyze the initial stages of realizing the 2014 Comprehensive Agreement on the Bangsamoro in the Philippines. The article bridges and expands on key theoretical insights based on three explanations suggested by previous research: 1) state capacity on promoting gender equality; 2) the mobilization of women's organizations; and 3) gender awareness of international actors. We find that the strategic actions of women's organizations combined with state capacity accelerated the implementation. However, their influence was dependent on whether or not the government prioritized the gender provisions, and whether international actors provided financial support to the agreement infrastructure.
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| 9. |
- Dyrrdal, Anita Verpe, et al.
(författare)
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Changes in design precipitation over the Nordic-Baltic region as given by convection-permitting climate simulations
- 2023
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Ingår i: Weather and Climate Extremes. - 2212-0947. ; 42
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Tidskriftsartikel (refereegranskat)abstract
- The increased risk of flooding due to global warming and subsequent heavy rainfall events in the Nordic-Baltic region, call for recommendations directed at long-term planning. One example of such recommendations are climate change allowances. These are often based on expected changes in design precipitation as given by climate model simulations, and are used as a buffer on top of current design values to avoid a future increased damage potential as a consequence of climate change. We here compute expected changes in precipitation design values, so-called climate factors (CFs), for the Nordic-Baltic region, based on 3 km convection permitting simulations from the Nordic Convection Permitting Climate Projections project. These have the advantage of explicitly resolving convection, which has been shown to be the main contributor to increased rainfall. We assess the dependence of the CFs on rainfall duration, return period, and geographical location, focusing on the summer (convective) season, short durations and the high emission scenario RCP8.5. We also compare these CFs to those computed from a non-convection permitting regional climate model ensemble. We found higher CFs for the longer return period, with only few exceptions, and distinctly higher CFs going from daily to sub-daily durations. However, the different simulations give conflicting results for very short-duration rainfall (<3 h). The huge difference in the climate sensitivity of driving GCMs dominates the magnitude of estimated return levels. Our analysis is shaped by the high computational costs of running convection permitting models, resulting in a very limited ensemble (3 members) representing a single emission scenario (RCP8.5). Therefore, we believe that combining results from convection permitting simulations with a larger ensemble (21 members) of non-convection permitting simulations adds value to the assessment of robust climate change allowances for heavy precipitation in the Nordic-Baltic region.
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| 10. |
- Floudas, Dimitrios, et al.
(författare)
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X-ray scattering reveals two mechanisms of cellulose microfibril degradation by filamentous fungi
- 2022
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Ingår i: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 88:17
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Tidskriftsartikel (refereegranskat)abstract
- Mushroom-forming fungi (Agaricomycetes) employ enzymatic and nonenzymatic cellulose degradation mechanisms, the latter presumably relying on Fenton-generated radicals. The effects of the two mechanisms on the cellulose microfibrils structure remain poorly understood. We examined cellulose degradation caused by litter decomposers and wood decomposers, including brown-rot and white-rot fungi and one fungus with uncertain wood decay type, by combining small- and wide-angle X-ray scattering. We also examined the effects of commercial enzymes and Fenton-generated radicals on cellulose using the same method. We detected two main degradation or modification mechanisms. The first characterized the mechanism used by most fungi and resembled enzymatic cellulose degradation, causing simultaneous microfibril thinning and decreased crystalline cellulose. The second mechanism was detected in one brown-rot fungus and one litter decomposer and was characterized by patchy amorphogenesis of crystalline cellulose without substantial thinning of the fibers. This pattern did not resemble the effect of Fenton-generated radicals, suggesting a more complex mechanism is involved in the destruction of cellulose crystallinity by fungi. Furthermore, our results showed a mismatch between decay classifications and cellulose degradation patterns and that even within litter decomposers two degradation mechanisms were found, suggesting higher functional diversity under current ecological classifications of fungi.IMPORTANCE Cellulose degradation by fungi plays a fundamental role in terrestrial carbon cycling, but the mechanisms by which fungi cope with the crystallinity of cellulose are not fully understood. We used X-ray scattering to analyze how fungi, a commercial enzyme mix, and a Fenton reaction-generated radical alter the crystalline structure of cellulose. Our data revealed two mechanisms involved in crystalline cellulose degradation by fungi: one that results in the thinning of the cellulose fibers, resembling the enzymatic degradation of cellulose, and one that involves amorphogenesis of crystalline cellulose by yet-unknown pathways, resulting in a patchy-like degradation pattern. These results pave the way to a deeper understanding of cellulose degradation and the development of novel ways to utilize crystalline cellulose.
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| 11. |
- Forsberg, Erika, Docent, 1976-, et al.
(författare)
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Examining Gender Inequality and Armed Conflict at the Subnational Level
- 2021
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Ingår i: Journal of Global Security Studies. - : Oxford University Press (OUP). - 2057-3170 .- 2057-3189. ; 6:2
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Tidskriftsartikel (refereegranskat)abstract
- A growing body of quantitative research points to a robust relationship between gender inequality and armed conflict. In order to progress our understanding of this relationship, we make two contributions. First, we identify three potential explanations as to why gender inequality can be associated with conflict—gender inequality norms, societal capacity, and gendered socioeconomic development—and suggest an empirical strategy to gauge the explanatory leverage of each explanation. Second, we offer a more nuanced treatment of the dependent variable at the subnational level, moving beyond a dichotomized view of armed conflict to accounting for both its level and type. We test our hypotheses using district-level data on gender inequality and conflicts in India, covering the 1989–2014 period. Our findings show that the three explanations do not produce the same outcomes in the data. We argue that this speaks to the need to adjudicate between different forms of mechanisms that can connect gender inequality to conflict. Our results show support for women's status being important for understanding a society's capacity to handle conflict nonviolently. On the negative side, gendered socioeconomic developments resulting in a male surplus create conditions conducive for armed conflict, particularly in urban areas. A more surprising finding is that the gender inequality norm, in and of itself, does not appear to have a strong effect on the risk of armed conflict. This does not mean that we can disregard the explanation, but it underlines that there can be inherent problems with this commonly used argument.
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| 12. |
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| 13. |
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| 14. |
- Fridén, Michael, et al.
(författare)
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Substitution analyses of foods with varying fat quality and the associations with all-cause mortality and impact of the FADS-1 genotype in elderly men
- 2023
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Ingår i: European Journal of Nutrition. - : Springer Berlin/Heidelberg. - 1436-6207 .- 1436-6215. ; 63, s. 145-153
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Tidskriftsartikel (refereegranskat)abstract
- Purpose To investigate associations between substitutions of foods varying in fat quality and all-cause mortality in elderly Swedish men and to examine effect measure modification by a gene involved in fatty acid desaturation (rs174550 FADS1).Methods Using Cox-regression models in the ULSAM cohort (n = 1133 men aged 71), we aimed to investigate; (1) Associations between the substitution of a nutrient or food for another on all-cause mortality (primary outcome) and CVD (secondary outcome) and (2) Associations between the addition of various fat-rich foods to the habitual diet and all-cause mortality and CVD. Subgroup analyses based on the rs174550 FADS1 genotype were conducted.Results Over a mean follow-up of 11.6–13.7 years, n = 774 died and n = 494 developed CVD, respectively. No clear associations were observed for the vast majority of substitution nor addition models. Adding saturated fatty acids (SFA) on top of the habitual diet was however associated with an increased risk of mortality in men with the CT/CC-genotype [HR (95% CI) 1.44 (1.05, 1.97)]. Post-hoc analyses showed an inverse association of substituting SFA with carbohydrates [HR (95% CI) 0.79 (0.65, 0.97)], which was somewhat stronger in men with the CT/CC-genotype compared to men carrying the TT-genotype.Conclusions Few associations were observed between diet and all-cause mortality and CVD in this population. However, substituting SFA with carbohydrates was associated with lower mortality in post-hoc analyses and adding SFA to the habitual diet increased mortality in men with the CT/CC-genotype. The latter observation is novel and warrants further investigation in larger cohort studies including women.
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| 15. |
- Huijser, Erika, et al.
(författare)
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Serum IFNα2 measured by single-molecule array associates with systemic disease manifestations in Sjögren's syndrome
- 2022
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Ingår i: Rheumatology (Oxford, England). - : Oxford University Press (OUP). - 1462-0332 .- 1462-0324. ; 61:5, s. 2156-2166
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Type I IFN (IFN-I) activation is a prominent feature of primary SS (pSS), SLE, and SSc. Ultrasensitive single-molecule array (Simoa) technology has facilitated the measurement of subfemtomolar concentrations of IFNs. Here, we aimed to measure IFNα2 in serum from pSS, SLE, and SSc using a Simoa immunoassay and correlate these levels to blood IFN-stimulated gene (ISG) expression and disease activity.METHODS: Serum IFNα2 was measured in patients with pSS (n = 85; n = 110), SLE (n = 24), and SSc (n = 23), and healthy controls (HC; n = 68) using an IFNα Simoa assay on a HD-X analyser. IFN-I pathway activation was additionally determined from serum by an IFN-I reporter assay and paired samples of whole blood ISG expression of IFI44, IFI44L, IFIT1, IFIT3, and MxA by RT-PCR or MxA-ELISA.RESULTS: Serum IFNα2 levels were elevated in pSS (median=61.3 fg/mL) compared to HC (median ≤5 fg/mL; p < 0.001) and SSc (median=11.6 fg/mL; p = 0.043), lower compared to SLE (median=313.5 fg/mL; p = 0.068), and positively correlated with blood ISG expression (r = 0.66-0.94; p < 0.001). Comparable to MxA-ELISA (AUC=0.93), IFNα2 measurement using Simoa identified pSS with high ISG expression (AUC=0.90) with 80-93% specificity and 71-84% sensitivity. Blinded validation in an independent pSS cohort yielded a comparable accuracy. Multiple regression indicated independent associations of autoantibodies, IgG, HCQ treatment, cutaneous disease and history of extraglandular manifestations with serum IFNα2 concentrations in pSS.CONCLUSION: Thus, Simoa serum IFNα2 reflects blood ISG expression in pSS, SLE, and SSc. In light of IFN-targeting treatments, Simoa could potentially be applied for patient stratification or retrospective analysis of historical cohorts.
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| 16. |
- Martin-Bertelsen, Birte, et al.
(författare)
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Revisiting the dissolution of cellulose in NaOH as "Seen" by X-rays
- 2020
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Ingår i: Polymers. - : MDPI AG. - 2073-4360. ; 12:2
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Tidskriftsartikel (refereegranskat)abstract
- Cotton production is reaching a global limit, leading to a growing demand for bio-based textile fibers produced by other means. Textile fibers based on regenerated cellulose from wood holds great potential, but in order to produce fibers, the components need to be dissolved in suitable solvents. Furthermore, the dissolution process of cellulose is not yet fully understood. In this study, we investigated the dissolution state of microcrystalline cellulose in aqueous NaOH by using primarily scattering methods. Contrary to previous findings, this study indicated that cellulose concentrations of up to 2 wt % are completely molecularly dissolved in 8 wt % NaOH. Scattering data furthermore revealed the presence of semi-flexible cylinders with stiff segments. In order to improve the dissolution capability of NaOH, the effects of different additives have been of interest. In this study, scattering data indicated that the addition of ZnO decreased the formation of aggregates, while the addition of PEG did not improve the dissolution properties significantly, although preliminary NMR data did suggest a weak attraction between PEG and cellulose. Overall, this study sheds further light on the dissolution of cellulose in NaOH and highlights the use of scattering methods to assess solvent quality. © 2020 by the authors.
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| 17. |
- Meklesh, Viktoriia, et al.
(författare)
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Characterization of the Colloidal Properties of Dissolved Organic Matter From Forest Soils
- 2022
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Ingår i: Frontiers in Soil Science. - : Frontiers Media SA. - 2673-8619.
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Tidskriftsartikel (refereegranskat)abstract
- Components of dissolved organic matter (DOM) span from sub-nm molecules to colloidal aggregates of several hundred nm. The colloidal fraction is important for the transport of organic matter and associated elements in the environment, and for the stability of DOM constituents with respect to microbial decomposition. This study focuses on the colloidal properties of DOM extracted from spruce forest soils of a chronosequence. The DOM samples were obtained by common water extraction procedures at 21 and 100°C, respectively. We applied an experimental approach combining chemical analysis with light and X-ray scattering techniques that informed on the colloidal size, charge, and structure of DOM. Results showed that two main types of colloids were present: semi-flexible cylinders and fractal aggregates. The cylinders consisted of carbohydrates, presumably hemicelluloses, while the aggregates were a composite material containing a large fraction of carbohydrates together with aliphatics and clay particles. These fractal aggregates dominated the cold-water extracts whereas the strong increase in total organic carbon by hot-water extraction caused a concomitantly strong increase of semi-flexible cylinders, which became the predominant species. Comparison between the chronosequence soils showed that with increasing forest age, the amount of carbon extracted per gram of soil declined and the concentration of the semi-flexible cylinders decreased. Thus, the distribution between the fractal aggregates and cylinders in the forest soil DOM samples depends on the composition of the soil organic matter and the leaching temperature. Changes in this distribution may have important implications for the reactivity and stability of DOM colloids.
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| 18. |
- Olsson, Erika, 1970-
(författare)
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Diet and common neurological disorders: cohort studies on dementia, Parkinson’s disease, and stroke
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Risk factors for dementia, Parkinson’s disease, and stroke have been widely studied but there are still research gaps concerning the role of diet for the development of these diseases. The overall aim of this thesis was to investigate whether various aspects of diet are associated with common disorders and diseases in the brain. Paper I and II are based on the Uppsala Longitudinal Study of Adult Men (ULSAM). Paper III and IV are based on the Swedish Mammography Cohort (SMC) and the Cohort of Swedish Men (COSM). In paper I, we investigated the associations between three different dietary patterns and incidence of Alzheimer’s disease (AD), dementia, and cognitive impairment. We observed no associations between adherence to the Healthy Diet Indicator and any of the outcomes studied, or between adherence to a Mediterranean-like diet (mMDS) and AD or dementia. There was a tendency towards a lower risk of cognitive impairment with higher adherence to the mMDS, and a weak association between adherence to a Low Carbohydrate High Protein score and higher risk of all-type dementia. Overall, there were no strong associations with the studied dietary patterns and development of dementia or cognitive impairment. In paper II, we found no associations of vitamin D measured as vitamin D intake, plasma 25-hydroxyvitamin D concentrations, or a vitamin D synthesis genetic risk score with incident AD, vascular dementia, dementia, or performance in the Mini-Mental State Examination.In paper III, we observed a weak higher risk of PD associated with milk consumption but there was no dose-response relationship. Thus, this association needs to be interpreted with caution. Fermented milk intake was not associated with PD.In paper IV, we found that a higher long-term milk consumption based on repeated measures of intake was not associated with total stroke, weakly and non-linearly associated with lower risk of cerebral infarction and higher risk of hemorrhagic stroke. Fermented milk consumption was not associated with any stroke type. Our results highlight the importance of repeated measurements of food intake, separate analyses of milk and fermented milk consumption, and to study stroke types separately.Despite the lack of strong associations, the findings of this thesis have increased our knowledge about the potential role of overall diet, vitamin D, and milk and fermented consumption in the prevention or development of common neurodegenerative diseases and stroke.
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| 19. |
- Olsson, Erika, 1970-, et al.
(författare)
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Milk and Fermented Milk Consumption and Risk of Stroke : Longitudinal Study
- 2022
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Ingår i: Nutrients. - : MDPI AG. - 2072-6643. ; 14:5
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Tidskriftsartikel (refereegranskat)abstract
- The role of milk and fermented milk consumption in stroke risk is unclear. We investigated associations of time-updated information on milk and fermented milk consumption (1997 and 2009) with total stroke, cerebral infarction, and hemorrhagic stroke risk among 79,618 Swedish women and men (mean age 61.3 years). During a mean follow-up of 17.7 years, we identified 9735 incident cases of total stroke, of which 7573 were cerebral infarctions, 1470 hemorrhagic strokes, and 692 unspecified strokes. Compared with an intake of 100 g/day of milk, the multivariable-adjusted hazard ratios (95% confidence interval) of cerebral infarction were 1.05 (1.02-1.08) for 0 g/day, 0.97 (0.95-0.99) for 200 g/day, 0.96 (0.92-1.00) for 400 g/day, 0.98 (0.94-1.03) for 600 g/day, and 1.01 (0.94-1.07) for 800 g/day. Corresponding estimates for hemorrhagic stroke were 0.98 (0.91-1.05) for 0 g/day, 1.02 (0.97-1.07) for 200 g/day, 1.07 (0.98-1.17) for 400 g/day, 1.13 (1.02-1.25) for 600 g/day, and 1.19 (1.03-1.36) for 800 g/day. No associations were observed between milk consumption and total stroke or for fermented milk consumption and any of the stroke outcomes. Higher long-term milk consumption based on repeated measures of intake was weakly and non-linearly associated with cerebral infarction, and was directly associated with hemorrhagic stroke.
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| 20. |
- Olsson, Erika, et al.
(författare)
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Milk and Fermented Milk Intake and Parkinson's Disease : Cohort Study
- 2020
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Ingår i: Nutrients. - : MDPI. - 2072-6643. ; 12:9
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Tidskriftsartikel (refereegranskat)abstract
- Milk and fermented milk consumption has been linked to health and mortality but the association with Parkinson's disease (PD) is uncertain. We conducted a study to investigate whether milk and fermented milk intakes are associated with incident PD. This cohort study included 81,915 Swedish adults (with a mean age of 62 years) who completed a questionnaire, including questions about milk and fermented milk (soured milk and yogurt) intake, in 1997. PD cases were identified through linkage with the Swedish National Patient and Cause of Death Registers. Multivariable-adjusted hazard ratios were obtained from Cox proportional hazards regression models. During a mean follow-up of 14.9 years, 1251 PD cases were identified in the cohort. Compared with no or low milk consumption (<40 mL/day), the hazard ratios of PD across quintiles of milk intake were 1.29 (95% CI 1.07, 1.56) for 40-159 mL/day, 1.19 (95% CI 0.99, 1.42) for 160-200 mL/day, 1.29 (95% CI 1.08, 1.53) for 201-400 mL/day, and 1.14 (95% CI 0.93, 1.40) for >400 mL/day. Fermented milk intake was not associated with PD. We found a weak association between milk intake and increased risk of PD but no dose-response relationship. Fermented milk intake was not associated with increased risk of PD.
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| 21. |
- Olsson, Jonas, et al.
(författare)
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An Analysis of (Sub-)Hourly Rainfall in Convection-Permitting Climate Simulations Over Southern Sweden From a User’s Perspective
- 2021
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Ingår i: Frontiers in Earth Science. - : Frontiers Media SA. - 2296-6463. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- To date, the assessment of hydrological climate change impacts, not least on pluvial flooding, has been severely limited by i) the insufficient spatial resolution of regional climate models (RCMs) as well as ii) the simplified description of key processes, e.g., convective rainfall generation. Therefore, expectations have been high on the recent generation of high-resolution convection-permitting regional climate models (CPRCMs), to reproduce the small-scale features of observed (extreme) rainfall that are driving small-scale hydrological hazards. Are they living up to these expectations? In this study, we zoom in on southern Sweden and investigate to which extent two climate models, a 3-km resolution CPRCM (HCLIM3) and a 12-km non-convection permitting RCM (HCLIM12), are able to reproduce the rainfall climate with focus on short-duration extremes. We use three types of evaluation–intensity-based, time-based and event-based–which have been designed to provide an added value to users of high-intensity rainfall information, as compared with the ways climate models are generally evaluated. In particular, in the event-based evaluation we explore the prospect of bringing climate model evaluation closer to the user by investigating whether the models are able to reproduce a well-known historical high-intensity rainfall event in the city of Malmö 2014. The results very clearly point at a substantially reduced bias in HCLIM3 as compared with HCLIM12, especially for short-duration extremes, as well as an overall better reproduction of the diurnal cycles. Furthermore, the HCLIM3 model proved able to generate events similar to the one in Malmö 2014. The results imply that CPRCMs offer a clear potential for increased confidence in future projections of small-scale hydrological climate change impacts, which is crucial for climate-proofing, e.g., our cities, as well as climate modeling in general.
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| 22. |
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| 23. |
- Petersson, M., et al.
(författare)
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Natural history and surgical outcome of Rathke's cleft cysts-A study from the Swedish Pituitary Registry
- 2022
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Ingår i: Clinical Endocrinology. - : Wiley. - 0300-0664 .- 1365-2265. ; 96:1, s. 54-61
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Tidskriftsartikel (refereegranskat)abstract
- Objective Rathke's cleft cysts are benign, embryological remnants in the pituitary gland. The majority of them are small and asymptomatic but a few may become large, and cause mass effects, pituitary hormone deficiencies and visual impairment. Recommendations for the follow-up of Rathke's cleft cysts vary since data on the natural history are sparse. Patients and Design Data at diagnosis and at 1, 5 and 10 years for patients with a Rathke's cleft cyst (434 at diagnosis, 317 females) were retrieved from the Swedish Pituitary Registry. Cysts <= 3 mm in diameter were excluded from the study. Measurements Data included demographics, cyst size, pituitary function, visual defects and surgery. Results The mean age at diagnosis was 45 years. In patients with cysts <10 mm in diameter (n = 204) 2.9% had pituitary hormone deficiencies and 2% had visual field impairments. Cyst size did not progress during the 5 years. Cysts with a diameter of >= 10 mm that were not operated (n = 174) decreased in size over the years (p < .01). Pituitary hormone deficiencies and visual impairments were more frequent (18% and 5.7%, respectively) but were stable over time. Transphenoidal surgery was performed in 56 patients of whom 51 underwent surgery before the 1-year follow-up. The mean cyst diameter at diagnosis was 18 mm (range: 930 mm), 36% had pituitary hormone deficiency, 45% had visual field defects and 20% had impaired visual acuity. One year after surgery 60% had no cyst remnants, 50% had a pituitary deficiency, 26% had visual field defects and 12% had impaired visual acuity. No major changes were observed after 5 years. Twelve of the operated patients had a follow-up at 10 years, in eight the cyst remnants or recurrences increased in size over time (p < .05). Conclusions Rathke's cleft cysts with a size less than 10 mm rarely grow and our results indicate that radiological follow-up can be restricted to 5 years. In contrast, progression of postoperative remnants or recurrent cysts is more likely and require long-term follow-up.
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| 24. |
- Vestin, Erika, et al.
(författare)
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Herpes simplex viral infection doubles the risk of dementia in a contemporary cohort of older adults : a prospective study
- 2024
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 97:4, s. 1841-1850
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Tidskriftsartikel (refereegranskat)abstract
- Background: Evidence indicates that herpes simplex virus (HSV) participates in the pathogenesis of Alzheimer’s disease (AD).Objective: We investigated AD and dementia risks according to the presence of herpesvirus antibodies in relation to anti-herpesvirus treatment and potential APOE ε4 carriership interaction.Methods: This study was conducted with 1002 dementia-free 70-year-olds living in Sweden in 2001–2005 who were followed for 15 years. Serum samples were analyzed to detect anti-HSV and anti-HSV-1 immunoglobulin (Ig) G, anti-cytomegalovirus (CMV) IgG, anti-HSV IgM, and anti-HSV and anti-CMV IgG levels. Diagnoses and drug prescriptions were collected from medical records. Cox proportional-hazards regression models were applied.Results: Cumulative AD and all-cause dementia incidences were 4% and 7%, respectively. Eighty-two percent of participants were anti-HSV IgG carriers, of whom 6% received anti-herpesvirus treatment. Anti-HSV IgG was associated with a more than doubled dementia risk (fully adjusted hazard ratio = 2.26, p = 0.031). No significant association was found with AD, but the hazard ratio was of the same magnitude as for dementia. Anti-HSV IgM and anti-CMV IgG prevalence, anti-herpesvirus treatment, and anti-HSV and -CMV IgG levels were not associated with AD or dementia, nor were interactions between anti-HSV IgG and APOE ε4 or anti-CMV IgG. Similar results were obtained for HSV-1.Conclusions: HSV (but not CMV) infection may be indicative of doubled dementia risk. The low AD incidence in this cohort may have impaired the statistical power to detect associations with AD.
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| 25. |
- Vestin, Erika, et al.
(författare)
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Herpes Simplex Viral Infection Doubles the Risk of Dementia in a Contemporary Cohort of Older Adults : A Prospective Study
- 2024
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 97:4, s. 1841-1850
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Tidskriftsartikel (refereegranskat)abstract
- Background: Evidence indicates that herpes simplex virus (HSV) participates in the pathogenesis of Alzheimer's disease (AD). Objective: We investigated AD and dementia risks according to the presence of herpesvirus antibodies in relation to antiherpesvirus treatment and potential APOE epsilon 4 carriership interaction. Methods: This studywas conducted with 1002 dementia-free 70-year-olds living in Sweden in 2001-2005 who were followed for 15 years. Serum samples were analyzed to detect anti-HSV and anti-HSV-1 immunoglobulin (Ig) G, anti-cytomegalovirus (CMV) IgG, anti-HSV IgM, and anti-HSV and anti-CMV IgG levels. Diagnoses and drug prescriptions were collected from medical records. Cox proportional-hazards regression models were applied. Results: CumulativeADand all-cause dementia incidences were 4% and 7%, respectively. Eighty-two percent of participants were anti-HSV IgG carriers, of whom 6% received anti-herpesvirus treatment. Anti-HSV IgG was associated with a more than doubled dementia risk (fully adjusted hazard ratio = 2.26, p = 0.031). No significant association was found with AD, but the hazard ratio was of the same magnitude as for dementia. Anti-HSV IgM and anti-CMV IgG prevalence, anti-herpesvirus treatment, and anti-HSV and -CMV IgG levels were not associated with AD or dementia, nor were interactions between anti-HSV IgG and APOE epsilon 4 or anti-CMV IgG. Similar results were obtained for HSV-1. Conclusions: HSV (but not CMV) infection may be indicative of doubled dementia risk. The low AD incidence in this cohort may have impaired the statistical power to detect associations with AD.
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