Opin vísindi

 

Flokkar í Opnum vísindum

Veldu flokk til að skoða.

Niðurstöður 1 - 9 af 9

Nýlega bætt við

Verk
Prophylactic Aspirin Dose and Preeclampsia
(2025) Kupka, Ellen; Hesselman, Susanne; Gunnarsdóttir, Jóhanna; Wikström, Anna Karin; Cluver, Catherine; Tong, Stephen; Hastie, Roxanne; Bergman, Lina; Faculty of Medicine
Importance: It is unclear whether a higher dose (150-160 mg) or a lower dose (75 mg) of aspirin should be used to prevent preeclampsia. Objectives: To compare the risk of preeclampsia and bleeding complications between women using 150 to 160 mg of aspirin and those using 75 mg of aspirin for preeclampsia prevention. Design, Setting, and Participants: This nationwide cohort study included 13828 women giving birth at 22 weeks' gestation or later in Sweden between January 2017 and December 2020 who used low dose aspirin (75-160 mg) during pregnancy. Data were analyzed from October to November 2023. Exposure: The use of 150 to 160 mg or 75 mg of aspirin in pregnancy. Main Outcome and Measures: The main outcome was a preeclampsia diagnosis recorded in the maternal birth record at the time of hospital discharge. The main safety outcome was postpartum hemorrhage, defined as bleeding more than 1000 mL after delivery. Relative risks (RRs) and 95% CIs were estimated using a doubly robust inverse probability-weighted regression adjustment model controlling for background characteristics. Results: In the total cohort of 13828 women, the mean (SD) age was 33.0 (5.5) years and 3003 women (21.7%) were nulliparous. Of the women, 4687 (33.9%) were prescribed 150 to 160 mg of aspirin, and 9141 (66.1%) were prescribed 75 mg of aspirin. A total of 10635 women (76.9%) had at least 2 dispensed prescriptions of low-dose aspirin. Among women using 150 to 160 mg of aspirin, 443 (9.5%) developed preeclampsia compared with 812 (8.9%) of those using 75 mg of aspirin (adjusted RR [aRR], 1.07; 95% CI, 0.93-1.24). Additionally, the risk of postpartum hemorrhage between the groups was similar, with 326 women (6.9%) using 150 to 160 mg of aspirin experiencing a postpartum hemorrhage compared with 581 (6.4%) in the 75-mg group (aRR, 1.08; 95% CI, 0.90-1.30). Conclusions and Relevance: In this cohort study of 13828 women, no difference was found in preeclampsia incidence or bleeding complications between those using 150 to 160 mg of aspirin vs 75 mg of aspirin during pregnancy for preeclampsia prevention. These findings suggest that either dose may be a reasonable choice when using aspirin to prevent preeclampsia. However, large randomized trials investigating aspirin dose in pregnancy are still needed.
Verk
Excessive events : The syntax and semantics of OVER-modification in Icelandic
(2025-04-16) Gast, Volker; Putnam, Michael T.; Jóhannsdóttir, Kristín Margrét; Faculty of Education
This article presents a detailed semantic and accompanying syntactic analysis of predicates denoting events that we describe as ‘excessive’ in Icelandic. Icelandic uses two types of strategies for marking of excess, the preposition yfir complemented by a reflexive pronoun or anaphor (e.g., Sara bakaði yfir sig ‘Sara baked too much’), and the verbal prefix of- (e.g., Sara of-bakaði kökuna ‘Sara over-baked the cake’). We argue that the former strategy expresses excess relative to the external argument, while the latter strategy expresses excess relative to the internal argument. We illustrate how the semantics of such predicates can be analysed using standard semantic approaches to degree predicates with some extensions, and how a decompositional approach to morphosyntax such as Distributed Morphology can capture these distinctions in a conceptually appealing way, with a plausible account of the syntax-semantics interface.
Verk
Epilepsy grand challenge 2025
(2025-09-15) Höller, Yvonne; Trinka, Eugen; Jacobs, Julia; Faculty of Psychology
Verk
Enhanced clinical evaluation of Alzheimer disease through rapid automatized naming of emotional pictures
(2025-07-10) Lafenthaler, Sandra; Höller, Yvonne; Bergmann, Jürgen; Kirschner, Margarita; Frey, Vanessa; Rossini, Fabio; Trinka, Eugen; Staffen, Wolfgang; Faculty of Psychology
Purpose: Naming tests are commonly incorporated as short versions into clinical evaluation of Alzheimer disease (AD), but evidence suggests they may overestimate semantic abilities. This study investigated whether a more challenging naming task could distinguish cognitively healthy individuals from those with amnestic mild cognitive impairment (aMCI) and mild AD, while more effectively capturing lexical-semantic deficits. Method: In this cross-sectionally study, 15 aMCI patients, 15 mild AD patients, and 20 cognitively healthy controls completed a rapid automatized naming (RAN) task using emotionally balanced object and action pictures. Regression analyses and receiver operating characteristic (ROC) curves were used to evaluate diagnostic accuracy and identify influencing factors. Results: Controls significantly outperformed aMCI and AD groups in response times and naming accuracy (all p-values <0.001). Negative pictures elicited slower responses and higher error rates in controls. While the “negative delay” effect was attenuated in patient groups, negative stimuli remained cognitively demanding, as indicated by increased errors. Emotional valence enhanced naming performance for action pictures in the control group, a pattern that diminished or was absent in the patient groups. Regression analyses showed significant associations between response times/error rates and group membership (both p-values <0.001), independent of age, sex, education, anxiety, and depression. ROC analysis revealed moderate diagnostic accuracy for classifying mild AD (AUC of 0.907 for response times; AUC of 0.861 for error rates), but not for aMCI. Conclusion: The RAN task effectively identifies early stages of AD and naming impairments across different stages of cognitive decline. The inhibitory effect of negative valence on lexical retrieval underscores the importance of incorporating emotional valence into naming assessments by further considering emotional reactivity (arousal) and different word classes.
Verk
DNA methylation analysis using long-read sequencing, methods and application
(2025) Sigurpálsdóttir, Brynja Dögg; Halldórsson, Bjarni Vilhjálmur; Department of Engineering
Beyond the primary genetic code, DNA carries a second layer of information in the form of epigenetic modification, predominantly DNA methylation, which do not alter the DNA sequence itself but instead alter how genetic information is interpreted and expressed. DNA methylation is a dynamic process that can change in response to aging and environmental exposures, such as smoking. Importantly, altered DNA methylation patterns have been associated with a wide range of diseases, including cardiovascular disorders and cancer risk. Characterization of the role of DNA methylation is requisite on accurate genome-wide detection of methylation, however traditional approaches provide limited coverage of the genome and cannot accurately resolve parent-of-origin specific patterns. Long-read sequencing (LRS) overcomes these limitations and offers new opportunities to study DNA methylation. This thesis makes three main contributions. First, we establish LRS as highly reliable for DNA methylation detection and introduce filtering strategies to ensure high-quality data. Second, we reveal that sequencing variants drive much of the correlation of methylation with gene expression. Third, we map age associated methylation changes across the genome and reveal parent-of-origin specific changes of imprinting fidelity. Together, these studies demonstrate the utility of LRS for large scale methylation analysis and highlight its potential to uncover novel biological insights, refine our understanding of epigenetic regulation and inform future translational applications. Key words: DNA methylation, long-read sequencing, nanopore sequencing, gene regulation, methylation age