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Krol, L.; Remmerswaal, L.; Groen, M.; Beek, J.G. van der; Sikkema, R.S.; Dellar M.E.; ... ; Schrama M.J.J. 2026

Landscape level associations between birds, mosquitoes and microclimates: possible consequences for disease transmission?

Article / Letter to editor

open access

Shalgunov, V.; Broek, S.L. van den; Andersen, I.V.; Raval, N.R.; Schäfer, G.; Barz, M.; ... ; Battisti, U.M. 2024

Evaluation of F-537-Tetrazine in a model for brain pretargeting imaging: comparison to N-(3-[18F] fluoro-5-(1,2,4,5-tetrazin-3-yl)benzyl)propan-1-amine

Article / Letter to editor

open access

Brain pretargeted nuclear imaging for the diagnosis of various neurodegenerative diseases is a quickly developing field. The tetrazine ligation is currently the most explored approach to achieve... Show moreBrain pretargeted nuclear imaging for the diagnosis of various neurodegenerative diseases is a quickly developing field. The tetrazine ligation is currently the most explored approach to achieve this goal due to its remarkable properties. In this work, we evaluated the performance of F-537-Tetrazine, previously developed by Biogen, and N-(3-[18F]fluoro-5-(1,2,4,5-tetrazin-3-yl)benzyl)propan-1-amine, previously developed in our group, thereby allowing for the direct comparison of these two imaging probes. The evaluation included synthesis, radiolabeling and a comparison of the physicochemical properties of the compounds. Furthermore, their performance was evaluated by in vitro and in vivo pretargeting models. This study indicated that N-(3-[18F] fluoro-5-(1,2,4,5-tetrazin-3-yl)benzyl)propan-1-amine might be more suited for brain pretargeted imaging. Show less

Diederiks, N.M.; Ruhaak, L.R.; Romijn, F.P.H.T.M.; Pieterse, M.M.; Smit, N.P.M.; Cobbaert, C.M. 2024

An LC-MS-based designated comparison method with similar performance to the Lp(a) reference measurement procedure to guide molar Lp(a) standardization

Article / Letter to editor

open access

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

Different glycosylation profiles of cystatin F alter the cytotoxic potential of natural killer cells

Article / Letter to editor

open access

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

Ruitenberg, M.F.L. 2024

Cognition and movement in neurodegenerative disorders: a dynamic duo

Article / Letter to editor

open access

Nagtzaam, M.A.M.; Louwerse, T.P. 2024

Geographical representation under a single nationwide district: the case of the Netherlands

Article / Letter to editor

open access

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

Ancient DNA of narrow-headed vole reveal common features of the Late Pleistocene population dynamics in cold-adapted small mammals

Article / Letter to editor

open access

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

Vriens, D.; Koster, E.J. de; Geus-Oei, L.F. de; Oyen, W.J.G.; EfFECTS trial consortium 2024

Preoperative stratification of cytologically indeterminate thyroid nodules by [18F]FDG-PET: can Orpheus bring back Eurydice?

Article / Letter to editor

open access

Marciello, M.; Cusati, V.; Nicolosi, F.; Saavedra-Rubio, K.; Pierrat, E.; Thonemann, N.; Laurent, A. 2024

Evaluating the economic landscape of hybrid-electric regional aircraft: a cost analysis across three time horizons

Article / Letter to editor

under embargo until 2025-01-16

This article presents the results of a prospective cost analysis of future regional aviation solutions, specifically focusing on hybrid-electric regional aircraft for 50 passengers. The study spans three time horizons (short term, medium term, long term) and employs a validated workflow to estimate costs for various solutions, including conventional, hybrid-electric, and hydrogen-based architectures. A specialized cost model is introduced to assess the electric components of the powertrain, emphasizing maintenance expenses and energy costs. Despite the environmental promise of hybrid and electric solutions, the results reveal significantly higher direct operating costs (up to 69.8%) compared to conventional options. The study highlights the importance of targeted policies to incentivize sustainable alternatives, suggesting potential solutions such as discouraging kerosene-based aircraft and promoting sustainable aviation fuel. These insights provide valuable guidance for industry stakeholders navigating the path toward a more sustainable and economically viable aviation future.

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Iwasaki, N.; Yoshioka, K. 2024

Thinking-for-speaking to describe motion events: English-Japanese bilinguals’ L1 English and L2 Japanese speech and gesture

Part of book or chapter of book

open access

Driessen, E.M.M.A. 2024

Stimulering en facilitering van burgerinitiatieven door de overheid: over de invulling van de ‘dienende overheid’ bij derde generatie burgerparticipatie

Doctoral Thesis

metadata only

Riedinger, M.A.; Mesbah, R.; Koenders, M.A.; Henderickx, J.G.E.; Smits, W.K.; El Filali, E.; ... ; Giltay, E.J. 2024

A healthy dietary pattern is associated with microbiota diversity in recently diagnosed bipolar patients: the Bipolar Netherlands Cohort (BINCO) study

Article / Letter to editor

open access

Hoogerwerf, M. 2024

Building bridges: a multidisciplinary approach to controlled human hookworm infection

Doctoral Thesis

open access

This thesis described the further development of the controlled human hookworm model and several applications of this model. First, the hookworm egg excretion is modelled over time using Bayesian... Show moreThis thesis described the further development of the controlled human hookworm model and several applications of this model. First, the hookworm egg excretion is modelled over time using Bayesian statistics, resulting in the description of a plateau phase in egg output. Repeated infections a re then investigated as a means to improve the accuracy and statistical power of this output as an outcome measure. The hereby established model is then applied in an immunization study, which shows that it is possible to develop a protective response against short-term larval infection. The skin phase and IgG1 seem to play a role in the development of this protection. Furthermore, gut microbiome changes during controlled hookworm infection are described. Also, volunteers’ motivations and decision making process are investigated, resulting in the characterization of controlled human infection participants as ‘deliberate decision-makers’ and not ‘money-oriented risk-takers’. Following up on the findings in the study described, the importance of a multidisciplinary approach for the improvement of controlled human infection trials is argued in the discussion, with several recommendations made for further collaborative efforts in order to maximise social and scientific output of these studies. Show less

Klatte, D.C.F. 2024

Early detection of pancreatic cancer in high-risk individuals

Doctoral Thesis

some documents under embargo until 2025-06-04

Earlier detection of pancreatic cancer is necessary to improve its poor prognosis. Currently, screening of the general population is not feasible due to the relatively low lifetime risk. However,... Show moreEarlier detection of pancreatic cancer is necessary to improve its poor prognosis. Currently, screening of the general population is not feasible due to the relatively low lifetime risk. However, up to one in ten cases occur in individuals with a strong family history of germline mutation carriers, known as high-risk individuals (HRIs). For these HRIs, pancreatic cancer surveillance in expert centers is recommended. The first part of this thesis focuses on evaluating the effectiveness of pancreatic cancer surveillance in carriers of a germline CD2KNA/p16 mutation who have a very high lifetime risk of developing pancreatic cancer. The second part focuses on various aspects to improve pancreatic cancer surveillance programs, including the study of biomarkers, risk stratification, and assessment of psychosocial aspects. Finally, attention is given to the identification of individuals at increased risk from the general population. Show less

Breekveldt, E.C.H. 2024

Colorectal cancer screening for average- and high-risk individuals: beyond one-size-fits-all

Doctoral Thesis

some documents under embargo until 2025-06-04

Colorectal cancer (CRC) screening programs have been established worldwide to prevent the development of CRC and to detect it early. CRC screening can be targeted at average- or high-risk... Show moreColorectal cancer (CRC) screening programs have been established worldwide to prevent the development of CRC and to detect it early. CRC screening can be targeted at average- or high-risk individuals. For average-risk individuals, the Dutch fecal immunochemical testing (FIT)-based CRC screening program was introduced in 2014, inviting all individuals aged 55-75 biennially. In Part I of this thesis, outcomes of the CRC screening program in the Netherlands are analyzed (i.e., CRC incidence, mortality, stage distribution, treatment). To optimize the balance between benefits and harms of CRC screening, risk stratification based on fecal hemoglobin concentrations after negative FIT could be the way forward. Part II describes the study protocol of a randomized controlled trail on personalized CRC screening and evaluates the information needs of the target population for personalized CRC screening strategies. For high-risk individuals, intensified CRC screening and surveillance may be needed, given these individuals have higher risk of developing CRC during their lifetime. Testicular cancer survivors treated with platinum-based chemotherapy can be considered high-risk individuals, as they have an increased risk of developing second primary gastrointestinal malignancies. Part III of this thesis explores the carcinogenesis of CRC and the yield of colonoscopy in these individuals. Show less

Kist, I.R. 2024

A fair balance: health data protection and the promotion of health data use for clinical and research purposes

Doctoral Thesis

open access

This thesis has found a balance between individual data protection rights and the free flow of data. On the one hand, this balance serves to protect the individual and his data. On the other hand,... Show moreThis thesis has found a balance between individual data protection rights and the free flow of data. On the one hand, this balance serves to protect the individual and his data. On the other hand, health care and health research must take place using personal data.A balanced approach can be found in the following four ways. Firstly, a broad(-er) interpretation of the lawful basis of consent can facilitate secondary health research. Secondly, the use of other lawful bases can be a solution for the legitimation of secondary health research. Furthermore, a separate legal ground for secondary research can be a solution to resolve the issue of a lawful basis for health research.Thirdly, a balance can be found in the individual’s autonomy vis-à-vis the accountability of the health institution and the attention drawn to the free flow of data. The focus is shifted from the individual’s control over his data towards the health institution with other lawful bases than consent and a fair balance between data protection rights and the free flow of data.Fourthly, a risk-based approach to monitoring compliance contributes to balancing the rights and interests of individuals with data sharing for health care and research. Show less

Verberne, S. 2024

Is de zoekmachine van de toekomst een chatbot?

Inaugural lecture

open access

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

Dijk, Y. van; Tol, L.S. van; Achterberg, W.P.; Zuidema, S.U.; Janus, S.I.M. 2024

COVID-19 measures implemented for nursing home staff and their perspectives on the importance of the measures: a qualitative study

Article / Letter to editor

open access

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

Li, Y.L.; Hassanzadeh, T.; Shamonin, D.P.; Reijnierse, M.; Mil, A.H.M.V.; Stoel, B.C. 2024

Rheumatoid arthritis classification and prediction by consistency-based deep learning using extremity MRI scans

Article / Letter to editor

open access

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

Zonneveld, A.J. van 2024

Van mecanorma tot ChatGPT

Event

open access

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

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