Pulmonary embolism is a serious and potentially life-threatening disease in the acute phase, and may also have a major impact on a patient’s daily life in the long run. The overall aim of this... Show morePulmonary embolism is a serious and potentially life-threatening disease in the acute phase, and may also have a major impact on a patient’s daily life in the long run. The overall aim of this thesis was evaluating important aspects of the post-pulmonary embolism syndrome with an emphasis on early diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) and the associated consequence for patients’ prognosis. Show less
Our current mycosis fungoides (MF) and Sezary Syndrome (SS) staging system includes blood-classification from B0-B2 for patch/plaque/tumour or erythroderma based on manual Sezary counts but results... Show moreOur current mycosis fungoides (MF) and Sezary Syndrome (SS) staging system includes blood-classification from B0-B2 for patch/plaque/tumour or erythroderma based on manual Sezary counts but results from our EORTC survey confirm these are rarely performed in patch/plaque/tumour MF, and there is a trend towards using flow cytometry to measure blood-class. Accurately assigning blood-class effects overall stage and the 'global response' used to measure treatment responses in MF/SS and hence impacts management. The EORTC Cutaneous Lymphoma Task Force Committee have reviewed the literature and held a Workshop (June 2017) to agree a definition of blood-class according to flow cytometry.No large study comparing blood-class as defined by Sezary count with flow cytometry has been performed in MF/SS. The definition of blood-class by flow cytometry varies between publications. Low-level blood involvement occurs in patch/plaque/tumour much less than erythroderma (p < 0.001). The prognostic relevance of blood involvement (B1 or B2) in patch/plaque/tumour is not known. Studies have not shown a statistically worse difference in prognosis in erythrodermic MF patients with low-level blood involvement (IIIB) versus those without (IIIA), but Sezary patients who by definition have a leukaemic blood picture (staged IVA1 or higher) have a worse prognosis.For consistency flow, definition for blood-class must be an objective measurement. We propose absolute counts of either CD4thornCD7-or CD4+CD26- where B0<250/mu L, B1 = 250/mu l -<1000/mu L and B2 >= 1000/mu L plus a T-cell blood clone. Fluctuations between B0 and B1 should not be considered in the treatment response criteria until further prognostic information is known. (C) 2018 The Authors. Published by Elsevier Ltd. Show less
This paper introduces the Bradley-Terry regression trunk model, a novel probabilistic approach for the analysis of preference data expressed through paired comparison rankings. In some cases, it... Show moreThis paper introduces the Bradley-Terry regression trunk model, a novel probabilistic approach for the analysis of preference data expressed through paired comparison rankings. In some cases, it may be reasonable to assume that the preferences expressed by individuals depend on their characteristics. Within the framework of tree-based partitioning, we specify a tree-based model estimating the joint effects of subject-specific covariates over and above their main effects. We, therefore, combine a tree-based model and the log-linear Bradley-Terry model using the outcome of the comparisons as response variable. The proposed model provides a solution to discover interaction effects when no a-priori hypotheses are available. It produces a small tree, called trunk, that represents a fair compromise between a simple interpretation of the interaction effects and an easy to read partition of judges based on their characteristics and the preferences they have expressed. We present an application on a real dataset following two different approaches, and a simulation study to test the model's performance. Simulations showed that the quality of the model performance increases when the number of rankings and objects increases. In addition, the performance is considerably amplified when the judges' characteristics have a high impact on their choices. Show less
Marques, M.L.; Ramiro, S.; Lunteren, M. van; Stal, R.A.; Landewe, R.B.; Sande, M. van de; ... ; Gaalen, F.A. van 2024
Objectives To investigate the prevalence of axial spondyloarthritis (axSpA) in patients with chronic back pain (CBP) of less than 2 years (2y) duration referred to the rheumatologist, the... Show moreObjectives To investigate the prevalence of axial spondyloarthritis (axSpA) in patients with chronic back pain (CBP) of less than 2 years (2y) duration referred to the rheumatologist, the development of diagnosis over time, and patient characteristics of those developing definite (d-)axSpA over 2y. Methods We analysed the 2y data from SPondyloArthritis Caught Early, a European cohort of patients (<45 years) with CBP (>= 3 months, <= 2y) of unknown origin. The diagnostic workup comprised evaluation of clinical SpA features, acute phase reactants, HLA-B27, radiographs and MRI (sacroiliac joints and spine), with repeated assessments. At each visit (baseline, 3 months, 1y and 2y), rheumatologists reported a diagnosis of axSpA or non-axSpA with level of confidence (LoC; 0-not confident at all to 10-very confident). Main outcome: axSpA diagnosis with LoC >= 7 (d-axSpA) at 2y. Results In 552 patients with CBP, d-axSpA was diagnosed in 175 (32%) at baseline and 165 (30%) at 2y. Baseline diagnosis remained rather stable: at 2y, baseline d-axSpA was revised in 5% of patients, while 8% 'gained' d-axSpA. Diagnostic uncertainty persisted in 30%. HLA-B27+ and baseline sacroiliitis imaging discriminated best 2y-d-axSpA versus 2y-d-non-axSpA patients. Good response to non-steroidal anti-inflammatory drugs and MRI-sacroiliitis most frequently developed over follow-up in patients with a new d-axSpA diagnosis. Of the patients who developed MRI-sacroiliitis, 7/8 were HLA-B27+ and 5/8 male. Conclusion A diagnosis of d-axSpA can be reliably made in nearly one-third of patients with CBP referred to the rheumatologist, but diagnostic uncertainty may persist in 5%-30% after 2y. Repeated assessments yield is modest, but repeating MRI may be worthwhile in male HLA-B27+ patients. Show less
This dissertation examines how in eighteenth-century Europe, naturalists sought to study, grasp and capture the world of fish. Working on the intersection of the history of science and book history... Show moreThis dissertation examines how in eighteenth-century Europe, naturalists sought to study, grasp and capture the world of fish. Working on the intersection of the history of science and book history, this research aims to shed light on how naturalists came to present themselves as authorities in an emerging field. It does so by focussing on a set of ‘fish books’, i.e., natural historical works that describe and depict fish. The first is Francis Willughby and John Ray’s "Historia piscium" (Oxford, 1686); the second Peter Artedi’s "Ichthyologia sive opera omnia de piscibus" (Leiden, 1738), and the third Marcus Élieser Bloch’s twelve volume series "Allgemeine Naturgeschichte der Fische" (Berlin, 1782–1795). These works are analysed alongside correspondences, manuscripts and natural historical collections. Together, these sources show that the development of the study of fish in this period can be best be understood as a process of continuous demarcation. This dissertation argues that the study of fish was subject to recurrent debates on subject, method and practitioner, and that such discussions were of both epistemological and social nature. In presenting their fish books, naturalists leveraged such discussions as to secure a place for themselves in the capricious environment of early modern natural history. Show less
Renewed calls for decolonizing anthropology in the 21st century raise the question of what work earlier waves of decolonization since the 1960s have left undone. Some of this work should focus on... Show moreRenewed calls for decolonizing anthropology in the 21st century raise the question of what work earlier waves of decolonization since the 1960s have left undone. Some of this work should focus on the classification of human differences, which figured prominently in all phases of the discipline’s history: as a methodology in its racist phases, as an object of study during its late colonial phase of professionalization, as self-critical reflexivity in the 1980s and 1990s, and as a renewed critique in the 21st century. Can a universal methodology of studying classifications of human kinds arise from the discipline’s past of colonial stereotyping? I argue affirmatively, through an approach that recognizes time as the epistemic condition that connects past and present positions to present and future methodologies. Firstly, my analysis distinguishes the parochial embedding in colonial culture of Durkheim and Mauss’ ideas about classification from their more universal intentions. This is then developed into a threefold reflexive and timeful methodology of studying classification’s nominal-descriptive, constructive, and interventionist dimensions—a process of adding temporality to the study of classification. Subsequently, Antenor Firmin’s 19th-century critique of racial classifications, and W. E. B. Du Bois’s theory of double consciousness help to show how this threefold methodology addresses the insufficiently theorized process of being classified and discriminated against through racial categories wielded by the powers that be. These arguments radicalize the essay’s timeful perspective by concluding that we need to avoid modernist uses of time as classification and adopt the aforementioned threefold methodology in order to put time in classifications of human kinds. This reverses modern positivism’s subordination to methodological rules of the epistemic conditions posed by contingent history and shows instead that the universal goals of methodology should be understood as a future ideal. Show less
Primair cutane B-cel lymfomen (CBCL) vormen een heterogene groep van non-Hodgkin lymfomen die zich primair in de huid manifesteren zonder aanwezigheid van extracutane lokalisaties. Volgens de in... Show morePrimair cutane B-cel lymfomen (CBCL) vormen een heterogene groep van non-Hodgkin lymfomen die zich primair in de huid manifesteren zonder aanwezigheid van extracutane lokalisaties. Volgens de in Nederland toegepaste EORTC-classificatie kunnen 3 typen CBCL onderscheiden worden: het primair cutaan immunocytoom of marginale zone B-cel lymfoom, het primair cutaan follikelcentrumcel lymfoom en het primair cutaan grootcellig B-cel lymfoom van het been. De studies in dit proefschrift hebben door middel van clinicopathologisch onderzoek en verschillende moleculair biologische technieken (waaronder genexpressie analyse, array-CGH en FISH-analyse) geresulteerd in de identificatie van een aantal nieuwe diagnostische en prognostische markers en daarnaast specifieke genetische kenmerken van de verschillende typen CBCL aangetoond. Deze resultaten hebben in de eerste plaats geleid tot een betere definitie van de verschillende typen CBCL. Daarnaast hebben de resultaten van deze studies een belangrijke rol gespeeld in de totstandkoming van een nieuwe consensus classificatie voor cutane lymfomen in 2005. In deze WHO-EORTC classificatie worden de volgende 3 belangrijkste typen CBCL onderscheiden: het primair cutaan marginale zone B-cel lymfoom, het primair cutaan follikelcentrum lymfoom en het primair cutaan grootcellig B-cel lymfoom, been type. Show less
Primary cutaneous lymphoma form a seperate group of non-Hodgkin lymphoma. Apart from the usual nodal presentation of a lymphoma, less frequently a lymphoma develops in an extranodal site. The skin... Show morePrimary cutaneous lymphoma form a seperate group of non-Hodgkin lymphoma. Apart from the usual nodal presentation of a lymphoma, less frequently a lymphoma develops in an extranodal site. The skin is, after the gastrointestinal tract, the most frequent site of extranodal lymphoma. If the skin is the primary site of involvement, i.e. no extracutaneous sites are involved at diagnosis, these lymphomas are called primary cutaneous lymphoma. In this thesis different types of primary cutaneous lymphoma are evaluated and discussed. In chapter 2 a large group of primary cutaneous CD30+ lympoproliferations is described and compared with a group of systemic CD30+ ALCL with skin localisations. Lymphomatoid papulosis and primary cutaneous CD30+ CTCL are closely related conditions and should be considered as a spectrum, with a comparable, excellent, prognosis. Multiagent chemotherapy (MAC) could not induce long lasting remissions, in fact all patients treated with MAC developed one or more (cutaneous) relapses. Therefor MAC is only indicated in case of extracuteneous localisations. In chapter 3 a group of CD30-negative T-cell lymphomas presenting in the skin that could not be diagnosed as MF, SS or SPTL are evaluated. In this group there were few survivors, apart from a rare group of patients with primary cutaneous lymphoma with small-medium sized CD4+/CD8-neoplastic T-cells (less than 30% large cells). In particular, patients with localized disease had an excellent prognosis. In chapter 4 haematological malignancies presenting in the skin and expressing CD56 were collected, both from the Dutch cutaneous lymphoma group and literature. In general these types of malignancies had a poor prognosis, except for patients with primary cutaneous CD30+ LPD, that showed a similar good prognosis as CD56-negative cases. Most cases belonged to the group of nasal-type NK/T-cell lymphoma and the group of CD4+, CD56+ hematodermic neoplasm (formerly also designated as blastic NK-cell lymphoma. In addition, CD56 was expressed in some SPTL, rare primary cutaneous CD30-negative large T-cell lymphomas, skin localisations of acute myeloid leukemia and CD30+ CTCL. In most of these groups CD56 expression did not affect prognosis. However, in SPTL CD56 expression proved a marker for gamma/delta T-cell origin and these cases showed a poorer prognosis as compared to SPTL with an alpha/beta phenotype (that were usually CD56-negative). In the new WHO-EORTC classification the category of SPTL only includes cases with an alpha/beta-positive phenotype, whereas cases with a gamma/delta positive phenotype are included in the provisional category of cutaneous gamma/delta-positive T-cell lymphoma. In chapter 5 a rare case of lymphomatoid papulosis with CD56-expression was presented and the frequency of co-expression of CD56 in primary cutaneous CD30+ LPD was analyzed. CD56 expression was found in approximately 10% of CD30+ LPD (both LyP and primary CD30+ CTCL). However, these CD56+ cases were not found to have a different prognosis from CD56 negative cases. In chapter 6 a European multicenter study on primary cutaneous large B-cell lymphomas is presented. Patients with primary cutaneous large B-cell lymphoma of the leg showed a poorer prognosis as patients with primary cutaneous follicle center cell lymphoma (PCFCCL). Moreover, round cell morphology was identified as a poor prognostic parameter. Although this was closely related to presentation on the leg(s), also in the group of PCFCCL the presence of a predominance of cells with round nuclei (centroblasts and immunoblasts) was associated with a poorer prognosis. The results of this study contributed to a new category in the WHO-EORTC classification, designated primary cutaneous large B-cell lymphoma (PCLBCL), leg-type, indicating that both patients with the classical presentation on the leg(s) as patients showing the same morphology and immunophenotype (bcl-2+, Mum-1/ IRF4+) on other sites are included in this group. Presentation with multifocal lesions proved to be a poor prognostic parameter for PCLBCL-leg-type, but not for PCFCCL. In chapter 7 treatment results in multifocal primary CBCL were analyzed. The main question in this study was if PCFCCL presenting with multifocal skin lesions should be treated with MAC. The study showed that MAC is only indicated in PCLBCL, leg-type and not in (multifocal) PCFCCL. Radiotherapy on multiple sites appeared equally effective as MAC in these patients. In chapter 8 the frequency of CNS-involvement in CBCL patients of the Dutch cutaneous lymphoma group. was evaluated. The frequency was low. Only 4/140 patients with a primary CBCL developed CNS involvement in the course of their disease. Interestingly 3 of these 4 patients were PCFCCL, a lymphoma usually with an excellent prognosis. Only 4 disease related deaths were reported in this group of which 3 with CNS involvement. The reason for this relatively high prevalence of CNS involvement in PCFCCL is unclear. The studies presented in this thesis have provided important information, which has contributed to the recent development of the WHO-EORTC classification. Moreover, they have contributed to updated guidelines for the treatment of the different types of primary cutaneous lymphomas, as presented in TABLE 2 in chapter 9. Show less
Schouten, T.M.; Koini, M.; Vos, F. de; Seiler, S.; Van der Grond, J.; Lechner, A.; ... ; Rombouts, S.A.R.B. 2016
Magnetic resonance imaging (MRI) is sensitive to structural and functional changes in the brain caused by Alzheimer's disease (AD), and can therefore be used to help in diagnosing the disease.... Show moreMagnetic resonance imaging (MRI) is sensitive to structural and functional changes in the brain caused by Alzheimer's disease (AD), and can therefore be used to help in diagnosing the disease. Improving classification of AD patients based on MRI scans might help to identify AD earlier in the disease's progress, which may be key in developing treatments for AD. In this study we used an elastic net classifier based on several measures derived from the MRI scans of mild to moderate AD patients (N = 77) from the prospective registry on dementia study and controls (N = 173) from the Austrian Stroke Prevention Family Study. We based our classification on measures from anatomical MRI, diffusion weighted MRI and resting state functional MRI. Our unimodal classification performance ranged from an area under the curve (AUC) of 0.760 (full correlations between functional networks) to 0.909 (grey matter density). When combining measures from multiple modalities in a stepwise manner, the classification performance improved to an AUC of 0.952. This optimal combination consisted of grey matter density, white matter density, fractional anisotropy, mean diffusivity, and sparse partial correlations between functional networks. Classification performance for mild AD as well as moderate AD also improved when using this multimodal combination. We conclude that different MRI modalities provide complementary information for classifying AD. Moreover, combining multiple modalities can substantially improve classification performance over unimodal classification. (C) 2016 The Authors. Published by Elsevier Inc. Show less
Alzheimer's disease (AD) patients show altered patterns of functional connectivity (FC) on resting state functional magnetic resonance imaging (RSfMRI) scans. It is yet unclear which RSfMRI... Show moreAlzheimer's disease (AD) patients show altered patterns of functional connectivity (FC) on resting state functional magnetic resonance imaging (RSfMRI) scans. It is yet unclear which RSfMRI measures are most informative for the individual classification of AD patients. We investigated this using RSfMRI scans from 77 AD patients (MMSE = 20.4 ± 4.5) and 173 controls (MMSE = 27.5 ± 1.8). We calculated i) FC matrices between resting state components as obtained with independent component analysis (ICA), ii) the dynamics of these FC matrices using a sliding window approach, iii) the graph properties (e.g., connection degree, and clustering coefficient) of the FC matrices, and iv) we distinguished five FC states and administered how long each subject resided in each of these five states. Furthermore, for each voxel we calculated v) FC with 10 resting state networks using dual regression, vi) FC with the hippocampus, vii) eigenvector centrality, and viii) the amplitude of low frequency fluctuations (ALFF). These eight measures were used separately as predictors in an elastic net logistic regression, and combined in a group lasso logistic regression model. We calculated the area under the receiver operating characteristic curve plots (AUC) to determine classification performance. The AUC values ranged between 0.51 and 0.84 and the highest were found for the FC matrices (0.82), FC dynamics (0.84) and ALFF (0.82). The combination of all measures resulted in an AUC of 0.85. We show that it is possible to obtain moderate to good AD classification using RSfMRI scans. FC matrices, FC dynamics and ALFF are most discriminative and the combination of all the resting state measures improves classification accuracy slightly. Show less
We propose a novel classification method that integrates into existing agile software development practices by collecting data records generated by software and tools used in the development... Show moreWe propose a novel classification method that integrates into existing agile software development practices by collecting data records generated by software and tools used in the development process. We extract features from the collected data and create visualizations that provide insights, and feed the data into a prediction framework consisting of a deep neural network. The features and results are validated against conceptual frameworks that model the development methodologies as similar processes in other contexts. Initial results show that the visualization and prediction techniques provide promising outcomes that may help development teams and management gain better understanding of past events and future risks. Show less
The term primary cutaneous B-cell lymphomas refers to a heterogeneous group of B-cell non-Hodgkin lymphomas, that present in the skin without evidence of extracutaneous disease at the time of... Show moreThe term primary cutaneous B-cell lymphomas refers to a heterogeneous group of B-cell non-Hodgkin lymphomas, that present in the skin without evidence of extracutaneous disease at the time of diagnosis. In recent years, there has been considerable debate regarding the classification and terminology of the group of primary cutaneous B-cell lymphomas and different classification schemes were used. In the new WHO-EORTC consensus classification for cutaneous lymphomas published in 2005, three major groups of primary cutaneous B-cell lymphoma are distinguished: primary cutaneous marginal zone B-cell lymphoma and primary cutaneous follicle center lymphoma with a good prognosis, and primary cutaneous diffuse large B-cell lymphoma, leg type with an intermediate prognosis. Studies presented in this thesis focus on three aspects of these primary cutaneous B-cell lymphomas: (1) the clinical usefulness of the WHO-EORTC classification in daily practice, (2) the validity of prognostic parameters reported in previous studies and identified in patient groups classified according to previously used classification schemes and (3) optimal management for the different types of primary cutaneous B-cell lymphomas as defined in the WHO-EORTC classification. Show less
Arend, B.W.H. van der; Verhagen, I.E.; Leeuwen, M. van; Arend, M.Q.T.P. van der; Casteren, D.S. van; Terwindt, G.M. 2023
BackgroundThere is a need for standardization of the definition of a migraine day for clinical and research purposes. MethodsWe prospectively compared different definitions of a migraine day with E... Show moreBackgroundThere is a need for standardization of the definition of a migraine day for clinical and research purposes. MethodsWe prospectively compared different definitions of a migraine day with E-diary data of n = 1494 patients with migraine. We used a baseline definition based on migraine characteristics with a duration of >= 4 hours OR triptan intake (independently from its effect) OR (visual) aura lasting 5-60 minutes. ResultsOf all migraine days defined by triptan intake only, 66.2% had a duration <4 hours. Adjusting the headache duration criterion to >= 30 minutes led to a decrease in days defined by triptan intake only and resulted in a 5.4% increase in total migraine days (equals 0.45 migraine day increase in monthly migraine days). These additional migraine days had a median duration of 2.5 hours. ConclusionWe propose to define a migraine day as follows: 1) (a) headache duration >= 30 minutes; (b) matching >= 2 of four characteristics: unilateral, pulsating, moderate to severe pain, aggravation by or causing avoidance of routine physical activity; and (c) during headache >= 1 of the following: nausea and/or vomiting, photophobia and phonophobia or 2) (visual) aura duration 5-60 minutes or 3) a day with headache for which acute migraine-specific medication is used irrespective of its effect. Show less
Carotid atherosclerosis, a disease in which plaque builds up inside the vessel wall, is a major cause of ischemic stroke. Traditionally, atherosclerosis risk stratification is heavily based on... Show moreCarotid atherosclerosis, a disease in which plaque builds up inside the vessel wall, is a major cause of ischemic stroke. Traditionally, atherosclerosis risk stratification is heavily based on the percentage of stenosis. However, a growing body of evidence suggests that luminal stenosis may not be the only cause of symptoms but the plaque composition may be more likely to impact the disease outcome. High-resolution vessel wall magnetic resonance imaging (VWMRI) is one of the most promising modalities for visualizing and evaluating carotid atherosclerotic plaque. The quantitative assessment of carotid atherosclerotic disease requires vessel wall segmentation and plaque classification, which is generally performed by manual delineations. However, manual contour tracing is labor-intensive, time-consuming and subject to inter-observer and inter-scan variability, which makes manual image analysis impractical for studies where large volume of data needs to be processed. Therefore, the main goal of this thesis is to: 1) develop approaches to automatically, robustly and reproducibly segment the carotid vessel wall and classify the atherosclerotic plaque from multi-spectral VWMRI; 2) validate the developed methods with reference standard; 3) extract the imaging biomarkers that can assist carotid artery disease evaluation. Show less
The aim of this European initiative is to facilitate a structured discussion to improve the next edition of the International Classification of Sleep Disorders (ICSD), particularly the chapter on... Show moreThe aim of this European initiative is to facilitate a structured discussion to improve the next edition of the International Classification of Sleep Disorders (ICSD), particularly the chapter on central disorders of hypersomnolence.The ultimate goal for a sleep disorders classification is to be based on the underlying neurobiological causes of the disorders with clear implication for treatment or, ideally, prevention and or healing. The current ICSD classification, published in 2014, inevitably has important shortcomings, largely reflecting the lack of knowledge about the precise neurobiological mechanisms underlying the majority of sleep disorders we currently delineate. Despite a clear rationale for the present structure, there remain important limitations that make it difficult to apply in routine clinical practice. Moreover, there are indications that the current structure may even prevent us from gaining relevant new knowledge to better understand certain sleep disorders and their neurobiological causes.We suggest the creation of a new consistent, complaint driven, hierarchical classification for central disorders of hypersomnolence; containing levels of certainty, and giving diagnostic tests, particularly the MSLT, a weighting based on its specificity and sensitivity in the diagnostic context.We propose and define three diagnostic categories (with levels of certainty): 1/"Narcolepsy" 2/"Idiopathic hypersomnia", 3/"Idiopathic excessive sleepiness" (with subtypes). (C) 2020 The Author(s). Published by Elsevier Ltd. Show less
