ObjectiveTo assess whether migraine may be genetically and/or causally associated with inflammatory bowel disease (IBD) or celiac disease.BackgroundMigraine has been linked to IBD and celiac... Show moreObjectiveTo assess whether migraine may be genetically and/or causally associated with inflammatory bowel disease (IBD) or celiac disease.BackgroundMigraine has been linked to IBD and celiac disease in observational studies, but whether this link may be explained by a shared genetic basis or could be causal has not been established. The presence of a causal association could be clinically relevant, as treating one of these medical conditions might mitigate the symptoms of a causally linked condition.MethodsLinkage disequilibrium score regression and two-sample bidirectional Mendelian randomization analyses were performed using summary statistics from cohort-based genome-wide association studies of migraine (59,674 cases; 316,078 controls), IBD (25,042 cases; 34,915 controls) and celiac disease (11,812 or 4533 cases; 11,837 or 10,750 controls). Migraine with and without aura were analyzed separately, as were the two IBD subtypes Crohn's disease and ulcerative colitis. Positive control analyses and conventional Mendelian randomization sensitivity analyses were performed.ResultsMigraine was not genetically correlated with IBD or celiac disease. No evidence was observed for IBD (odds ratio [OR] 1.00, 95% confidence interval [CI] 0.99–1.02, p = 0.703) or celiac disease (OR 1.00, 95% CI 0.99–1.02, p = 0.912) causing migraine or migraine causing either IBD (OR 1.08, 95% CI 0.96–1.22, p = 0.181) or celiac disease (OR 1.08, 95% CI 0.79–1.48, p = 0.614) when all participants with migraine were analyzed jointly. There was some indication of a causal association between celiac disease and migraine with aura (OR 1.04, 95% CI 1.00–1.08, p = 0.045), between celiac disease and migraine without aura (OR 0.95, 95% CI 0.92–0.99, p = 0.006), as well as between migraine without aura and ulcerative colitis (OR 1.15, 95% CI 1.02–1.29, p = 0.025). However, the results were not significant after multiple testing correction.ConclusionsWe found no evidence of a shared genetic basis or of a causal association between migraine and either IBD or celiac disease, although we obtained some indications of causal associations with migraine subtypes. Show less
BackgroundThe 2022 consensus statement of the European Atherosclerosis Society (EAS) on lipoprotein(a) (Lp(a)) recognizes the role of Lp(a) as a relevant genetically determined risk factor and... Show moreBackgroundThe 2022 consensus statement of the European Atherosclerosis Society (EAS) on lipoprotein(a) (Lp(a)) recognizes the role of Lp(a) as a relevant genetically determined risk factor and recommends its measurement at least once in an individual's lifetime. It also strongly urges that Lp(a) test results are expressed as apolipoprotein (a) (apo(a)) amount of substance in molar units and no longer in confounded Lp(a) mass units (mg/dL or mg/L). Therefore, IVD manufacturers should transition to molar units. A prerequisite for this transition is the availability of an Lp(a) Reference Measurement Procedure (RMP) that allows unequivocal molecular detection and quantification of apo(a) in Lp(a). To that end an ISO 17511:2020 compliant LC-MS based and IFCC-endorsed RMP has been established that targets proteotypic peptides of apolipoprotein(a) (apo(a)) in Lp(a). The RMP is laborious and requires highly skilled operators. To guide IVD-manufacturers of immunoassay-based Lp(a) test kits in the transition from mass to molar units, a Designated Comparison Method (DCM) has been developed and evaluated.MethodsTo assess whether the DCM provides equivalent results compared to the RMP, the procedural designs were compared and the analytical performance of DCM and RMP were first evaluated in a head-to-head comparison. Subsequently, apo(a) was quantified in 153 human clinical serum samples. Both DCM and RMP were calibrated using external native calibrators that produce results traceable to SRM2B. Measurement uncertainty (MU) was checked against predefined allowable MU.ResultsThe major difference in the design of the DCM for apo(a) is the use of only one enzymatic digestion step. The analytical performance of the DCM and RMP for apo(a) is highly similar. In a direct method comparison, equivalent results were obtained with a median regression slope 0.997 of and a median bias of - 0.2 nmol/L (- 0.2%); the intermediate imprecision of the test results was within total allowable error (TEa) (CVa of 10.2% at 90 nmol/L).ConclusionsThe semi-automated, higher throughput, LC-MS-based method for Lp(a) meets the predefined analytical performance specifications and allowable MU and is hence applicable as a higher order Designated Comparison Method, which is ideally suited to guide IVD manufacturers in the transition from Lp(a) mass to molar units. Show less
Senjor, E.; Pirro, M.; Svajger, U.; Prunk, M.; Sabotic, J.; Jewett, A.; ... ; Kos, J. 2024
Cystatin F, a cysteine peptidase inhibitor, is a potent modulator of NK cytotoxicity. By inhibiting granule-mediated cytotoxicity pathway, cystatin F induces formation of non-functional NK cell... Show moreCystatin F, a cysteine peptidase inhibitor, is a potent modulator of NK cytotoxicity. By inhibiting granule-mediated cytotoxicity pathway, cystatin F induces formation of non-functional NK cell stage, called split-anergy. We show that N-glycosylation determines the localization and cellular function of cystatin F. Cystatin F mostly exhibited high-mannose glycosylation in U-937 cells, both high-mannose and complex glycosylation in NK-92 and primary NKs, and predominantly complex glycosylation in super-charged NKs. Manipulating N-glycosylation with kifunensine increased high-mannose glycosylation of cystatin F and lysosome localisation, which decreased cathepsin C activity and reduced NK cytotoxicity. Mannose-6-phosphate could significantly reduce the internalization of extracellular cystatin F. By comparing NK cells with different cytotoxic potentials, we found that high-mannose cystatin F was strongly associated with lysosomes and cathepsin C in NK-92 cell line. In contrast, in highly cytotoxic super-charged NKs, cystatin F with complex glycosylation was associated with the secretory pathway and less prone to inhibit cathepsin C. Modulating glycosylation to alter cystatin F localisation could increase the cytotoxicity of NK cells, thereby enhancing their therapeutic potential for treating cancer patients. Show less
Previous studies have demonstrated the common occurrence of constituency focus in parliamentary questions, which is most often attributed to electoral incentives. If an electoral system makes use... Show morePrevious studies have demonstrated the common occurrence of constituency focus in parliamentary questions, which is most often attributed to electoral incentives. If an electoral system makes use of a single nationwide district, however, these district-oriented electoral incentives do not apply. MPs may still substantively represent a geographical region, because they are motivated to stand up for a specific region for other reasons. This article explores the extent to which Dutch MPs pay attention in parliamentary questions and debates to specific regions. We find that those with stronger ties to a region, and especially MPs who reside in a region, are more likely to mention it in parliamentary questions and speeches. In addition, we find that this effect is stronger for provinces where regional attachment among residents is relatively stronger. Show less
Baca, M.; Popović, D.; Agadzhanyan, A.K.; Baca, K.; Conard, N.J.; Fewlass, H.; ... ; Nadachowski, A. 2024
The narrow-headed vole, collared lemming and common vole were the most abundant small mammal species across the Eurasian Late Pleistocene steppe-tundra environment. Previous ancient DNA studies of... Show moreThe narrow-headed vole, collared lemming and common vole were the most abundant small mammal species across the Eurasian Late Pleistocene steppe-tundra environment. Previous ancient DNA studies of the collared lemming and common vole have revealed dynamic population histories shaped by climatic fluctuations. To investigate the extent to which species with similar adaptations share common evolutionary histories, we generated a dataset comprised the mitochondrial genomes of 139 ancient and 6 modern narrow-headed voles from several sites across Europe and northwestern Asia covering approximately the last 100 thousand years (kyr). We inferred Bayesian time-aware phylogenies using 11 radiocarbon-dated samples to calibrate the molecular clock. Divergence of the main mtDNA lineages across the three species occurred during marine isotope stages (MIS) 7 and MIS 5, suggesting a common response of species adapted to open habitat during interglacials. We identified several time-structured mtDNA lineages in European narrow-headed vole, suggesting lineage turnover. The timing of some of these turnovers was synchronous across the three species, allowing us to identify the main drivers of the Late Pleistocene dynamics of steppe- and cold-adapted species. Show less
Oratie uitgesproken door Prof. Dr. Suzan Verberne bij de aanvaarding van het ambt van hoogleraar Natural Language Processing aan de Universiteit Leiden op maandag 3 juni 2024_______________________... Show moreOratie uitgesproken door Prof. Dr. Suzan Verberne bij de aanvaarding van het ambt van hoogleraar Natural Language Processing aan de Universiteit Leiden op maandag 3 juni 2024____________________________________________________________Text also in English : Is the search engine of the future a chatbot? Show less
Background: Measures against COVID-19 in nursing homes affected not only clients but also staff. However, staff perspectives on the importance of these measures remain underexplored. Objective: To... Show moreBackground: Measures against COVID-19 in nursing homes affected not only clients but also staff. However, staff perspectives on the importance of these measures remain underexplored. Objective: To investigate measures related to staff during the COVID-19 pandemic, staff perspectives of important measures and the involvement of staff in deciding on these measures. Design: A qualitative study. Setting(s): We analysed minutes of nursing home outbreak teams in the Netherlands and conducted group meetings with Dutch nursing home staff in different positions, prioritizing measures and discussing staff' involvement in deciding on the measures. Participants were recruited purposefully. Participants: The minutes of 41 nursing home organizations were collected during March-November, 2020. Four group meetings were organized in the same period, each with 5 to 7 participants, resulting in 23 participants. Methods: The meeting minutes were analysed using qualitative content analysis, whereas reflexive thematic analysis was used for the group meeting data. The group meetings were conducted online and structured by the Nominal Group Technique to discuss the importance of measures for staff. Results: Measures implemented for staff focused on prevention of COVID-19 transmission, (suspension of) educational activities, testing, additional tasks and staffing capacity, promoting wellbeing, and other means of support. The implemented measures overlapped with the measures considered important by staff. In addition, staff considered measures on decision-making support and communication to be important. Staff prioritized the measures in the group meetings because they affected their well-being, workforce scheduling, decision-making, or infection prevention. Furthermore, the group meetings revealed that decision-making shifted from mainly implementing national measures to more context-adjusted decision-making in the staff's or clients' situations. Conclusions: We showed that although nursing home staff were not always involved in decisionmaking during the first COVID-19 wave, there was overlap between the measures implemented by the organizations and measures considered important by staff. We suggest that organizations Show less
Predicting the development of rheumatoid arthritis (RA) in an early stage through magnetic resonance imaging (MRI) can initiate timely treatment and improve long-term patient outcomes. Although... Show morePredicting the development of rheumatoid arthritis (RA) in an early stage through magnetic resonance imaging (MRI) can initiate timely treatment and improve long-term patient outcomes. Although manual prediction is time-consuming and requires expert knowledge, automatic RA prediction has not been fully investigated. While standard models fail to achieve acceptable performance, we present a consistency-based deep learning framework to classify and predict RA automatically and precisely, including an output-standardized model, customized self-supervised pretraining and a loss function that is based on label consistency between original and augmented inputs. For training and evaluation, we used a database, containing 5945 MRI scans of carpal, metacarpophalangeal (MCP), and metatarsophalangeal (MTP) joints, from 2151 subjects obtained over a period of ten years. Four (three classification- and one prediction-) tasks were defined to distinguish two patient groups (with recent-onset arthritis and clinically suspect arthralgia) from healthy controls and RA from other arthritis patients within the recent-onset arthritis group, and predict RA development in a period of two years within the clinically suspect arthralgia group. The proposed method was evaluated with the area under the receiver operating curve (AUROC) on a separate test set, achieving mean AUROCs of 83.6%, 83.3%, and 69.7% in the three classification tasks, and 67.8% in the prediction task. This proves the existence of early signs of RA in MRI and the potential of a consistency-based deep learning model to detect these early signs and predict RA Show less
Background: The risk of urinary tract infections (UTIs) is increased by unnecessary placement and prolonged use of urinary catheters. Aim: To assess whether inappropriate use of catheters and... Show moreBackground: The risk of urinary tract infections (UTIs) is increased by unnecessary placement and prolonged use of urinary catheters. Aim: To assess whether inappropriate use of catheters and catheter-associated UTI were reduced through patient participation. Methods: In this multicentre, interrupted time-series and before-and-after study, we implemented a patient-centred app which provides catheter advice for patients, together with clinical lessons, feedback via e-mails and support rounds for staff members. Data on catheter use and infections were collected during a six-month baseline and a six-month intervention period on 13 wards in four hospitals in the Netherlands. Dutch Trial Register: NL7178. Findings: Between June 25th, 2018 and August 1st, 2019, 6556 patients were included in 24 point-prevalence surveys, 3285 (50%) at baseline and 3271 (50%) during the intervention. During the intervention 249 app users and a median of seven new app users per week were registered (interquartile range: 5.5e13.0). At baseline, inappropriate catheter use was registered for 175 (21.9%) out of 798 catheters, compared to 55 (7.0%) out of 786 during the intervention. Time-series analysis showed a non-significant decrease of inappropriate use of 5.8% (95% confidence interval: e3.76 to 15.45; P ¼ 0.219), with an odds ratio of 0.27 (0.19e0.37; P < 0.001). Catheter-associated UTI decreased by 3.0% (1.3e4.6; P ¼ 0.001), with odds ratio 0.541 (0.408e0.716; P < 0.001). Show less
Rede uitgesproken door Prof. dr. Anton Jan van Zonneveld ter gelegenheid van zijn afscheid als hoogleraarNierziekten, in het bijzonder de experimentele vasculaire geneeskunde aan de Universiteit... Show moreRede uitgesproken door Prof. dr. Anton Jan van Zonneveld ter gelegenheid van zijn afscheid als hoogleraarNierziekten, in het bijzonder de experimentele vasculaire geneeskunde aan de Universiteit Leiden op vrijdag 31 mei 2024 Show less
Tuberculosis (TB) is associated with 1.5 million deaths annually. There is a need exists to optimize both current as well as novel antibiotic combination treatment strategies to improve the... Show moreTuberculosis (TB) is associated with 1.5 million deaths annually. There is a need exists to optimize both current as well as novel antibiotic combination treatment strategies to improve the effectiveness and safety of treatments against TB. This PhD thesis has described how various quantitative pharmacology modeling approaches can contribute to the further development and optimization of both existing and novel therapies and treatment strategies against TB. Show less
Dental calculus. This small, hard, inconspicuous substance that forms on the teeth of humans and animals contains a surprising amount of information about our lives. During its formation and growth... Show moreDental calculus. This small, hard, inconspicuous substance that forms on the teeth of humans and animals contains a surprising amount of information about our lives. During its formation and growth as a living biofilm, it accumulates a wide variety particles, especially bacteria and food debris.What makes this so interesting to archaeologists is that, when plaque hardens and forms dental calculus, these particles become trapped and well-protected against removal and degradation during hundreds to thousands of years, preserving a picture of past activities.The major problem—one of the major problems, for there are several—one of the many major problems is that this picture was never a complete picture of a lifetime of activities, and that picture fades over time. We know that these problems exist and that they limit our interpretations of past activities. What we need to do is approach these problems at a fundamental level. In my dissertation I introduce a protocol for growing artificial dental calculus. Working with a very controlled model allows me to explore the influence of a wide range of factors that may affect the uptake of particles into dental calculus, and better explain why and how our picture is incomplete. Show less
Space data provide timely and reliable information that enables a wide variety of civil and commercial applications. Thanks to their volume, velocity, variety, and veracity, space big data create... Show moreSpace data provide timely and reliable information that enables a wide variety of civil and commercial applications. Thanks to their volume, velocity, variety, and veracity, space big data create the potential for additional benefits from space data.The benefits of space big data depend on the ways in which data are collected, accessed, used, and disseminated, therefore the laws and data policies that affect them should be studied. This thesis answers the question ‘How could space big data be regulated to address existing legal challenges and enhance their benefits?’. In particular, it identifies the laws and data policies that are relevant to the collection, access, use, and dissemination of space big data, among the legal frameworks that govern activities involving space or data. It also assesses the impact of the relevant laws and data policies, in terms of the limitations they impose on data collection, access, use, and dissemination. From the analysis of the relevant laws and data policies and their impact, the thesis draws the areas where their application encounters difficulties and describes the respective legal challenges. Based on these findings, recommendations are provided for overcoming the legal challenges and enhancing the collection, access, use, and dissemination of data, and by extension, their benefits. Show less
In this dissertation, Dutch secondary school teachers’ attitudes, knowledge, noticing skills and reasoned practices regarding culturally responsive teaching in a multicultural classroom context,... Show moreIn this dissertation, Dutch secondary school teachers’ attitudes, knowledge, noticing skills and reasoned practices regarding culturally responsive teaching in a multicultural classroom context, were examined. These components of culturally responsive teaching were addressed in three explorative, qualitative studies. In the first study, expert teachers’ reasoned practices were examined by in depth interviews. In the second and third study, spherical video-based virtual reality (SV-VR) clips of a multicultural classroom were used to provide teachers an immersive, authentic and comparable experience. The second study focussed on student teachers’ and expert teachers’ noticing through a cultural lens. In the third study, the SV-VR clips were used for deeper reflections in focus groups through which expert teachers’ culturally responsive attitudes, knowledge, noticing skills and reasoned practices were examined. The main results of this dissertation show that expert teachers teaching at Dutch multicultural schools indicate that working on a good interpersonal relationship with students is crucial. Moreover, the importance of adopting a genuinely curious attitude regarding students’ Funds of Knowledge/ Identity is often referred to. Such knowledge is also seen as necessary to notice relevant classroom events. Recommendations are made for teacher education regarding preparing teachers to teach multicultural classes. Show less
Lung cancer is the leading cause of cancer death in the Netherlands. For years chemotherapy was the only (palliative) treatment, with a short survival of only months. Since the introduction of... Show moreLung cancer is the leading cause of cancer death in the Netherlands. For years chemotherapy was the only (palliative) treatment, with a short survival of only months. Since the introduction of immunotherapy in 2015, this survival has increased significantly, with the first results showing a survival of even a few years. However, the response rate is relatively low, the treatment is expensive and the (low percentage of) side effects are severe. Therefore a biomarker is needed to predict which patients would benefit of immunotherapy.This thesis is about the search for a new biomarker. With the use of the RNA of platelets, proteins, tumor markers in blood and a an electronic nose for exhaled breath, we tried to find a non-invasive biomarker for the prediction of response on immunotherapy and for the (future) use in clinical practice, some of which are promising. Show less
