73 results on '"J. van den Hurk"'
Search Results
2. Validation of a wireless patch sensor to monitor mobility tested in both an experimental and a hospital setup: A cross-sectional study.
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Niek Koenders, Joost P H Seeger, Teun van der Giessen, Ties J van den Hurk, Indy G M Smits, Anne M Tankink, Maria W G Nijhuis-van der Sanden, and Thomas J Hoogeboom
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Medicine ,Science - Abstract
PURPOSE:To assess the concurrent validity of a wireless patch sensor to monitor time lying, sitting/standing, and walking in an experimental and a hospital setup. METHODS:Healthy adults participated in two testing sessions: an experimental and real-world hospital setup. Data on time lying, sitting/standing, and walking was collected with the HealthPatch and concurrent video recordings. Validity was assessed in three ways: 1. test for mean differences between HealthPatch data and reference values; 2. Intraclass Correlation Coefficient analysis (ICC 3.1 agreement); and 3. test for mean differences between posture detection accuracies. RESULTS:Thirty-one males were included. Significant mean differences were found between HealthPatch data and reference values for sitting/standing (mean 14.4 minutes, reference: 12.0 minutes, p
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- 2018
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3. Good Days and Bad Days: Measuring Health-Related Quality of Life in People With Epilepsy
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Tim A. Kanters, Job van Exel, Jacqueline Ardesch, Marie-José Enders-Slegers, J. Mourits, Werner B. F. Brouwer, Louis Wagner, Valérie Wester, M. de Ruiter, Saskia de Groot, Matthijs Versteegh, I. Corro-Ramos, H. Marell, U. de Wit, J. van den Hurk-van Schadewijk, S. le Cessie, H. Verhoeven, Health Economics (HE), Health Technology Assessment (HTA), Erasmus School of Health Policy & Management, and Applied Economics
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Adult ,Male ,Pediatrics ,medicine.medical_specialty ,episodic illness ,episodic conditions ,Cost-Benefit Analysis ,Population ,Context (language use) ,Disease ,HRQoL ,Epilepsy ,Dogs ,Quality of life ,SDG 3 - Good Health and Well-being ,episodic diseases ,EQ-5D ,Surveys and Questionnaires ,medicine ,Animals ,Humans ,education ,seizures ,Health related quality of life ,education.field_of_study ,business.industry ,Health Policy ,Public Health, Environmental and Occupational Health ,Regression analysis ,Middle Aged ,medicine.disease ,Service Animals ,humanities ,quality of life ,utility ,epilepsy ,Female ,business - Abstract
Objectives: Cost-effectiveness analyses typically require measurement of health-related quality of life (HRQoL) to estimate quality-adjusted life-years. Challenges with measuring HRQoL arise in the context of episodic conditions if patients are less likely—or even unable—to complete surveys when having disease symptoms. This article explored whether HRQoL measured at regular time intervals adequately reflects the HRQoL of people with epilepsy (PWE). Methods: Follow-up data from the Epilepsy Support Dog Evaluation study on the (cost-)effectiveness of seizure dogs were used in which HRQoL is measured in 25 PWE with the EQ-5D at baseline and every 3 months thereafter. Seizure count is recorded daily using a seizure diary. Regression models were employed to explore whether PWE were more likely to complete the HRQoL survey on a good day (ie, when seizures are absent or low in frequency compared with other days) and to provide an estimate of the impact of reporting HRQoL on a good day on EQ-5D utility scores. Results: A total of 111 HRQoL measurements were included in the analyses. Regression analyses indicated that the day of reporting HRQoL was associated with a lower seizure count (P
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- 2021
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4. Self-perceived cognitive functioning and quality of life among cancer survivors: results from the PROFILES registry
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Simone, Oerlemans, Sanne B, Schagen, Corina J, van den Hurk, Olga, Husson, Dounya, Schoormans, and Lonneke V, van de Poll-Franse
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Male ,Cognition ,Cancer Survivors ,Lymphoma, Non-Hodgkin ,Surveys and Questionnaires ,Quality of Life ,Humans ,Registries ,Thyroid Neoplasms ,Melanoma ,Fatigue - Abstract
The aim was to investigate the level of self-perceived cognitive functioning and its associated factors among a large population-based cohort of cancer survivors and their matched controls.Data were obtained from population-based PROFILES registry cohorts, including colon, rectum, prostate or thyroid cancer, Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia, multiple myeloma (MM), melanoma, or basal cell carcinoma (BCC)/squamous cell carcinoma (SCC). All patients completed the EORTC QLQ-C30 from which self-perceived cognitive functioning, fatigue, functioning, and global health status/quality of life (GHS/QoL) were used. The PROFILES registry data were linked with the Netherlands Cancer Registry to obtain sociodemographic and clinical data.Six thousand seven hundred eighty-six survivors were included (response rate=76%). Survivors, except for melanoma and BCC/SCC, reported on average lower self-perceived cognitive functioning scores compared to their matched controls (all p's0.01). Largest differences with the norm were observed in thyroid cancer, HL, NHL and MM, and younger survivors (50 years). Survivors with lower emotional functioning and more fatigue were more likely to report impaired self-perceived cognitive functioning.Self-perceived impaired cognitive functioning is prevalent among a wide range of cancer survivors, especially among survivors50 years. Approaches targeting cognitive problems including attention for co-occurring symptoms such as fatigue and emotional impairments are needed to improve care for these patients.Cancer survivors and clinicians should be aware that impaired self-perceived cognitive functioning is a frequently reported consequence of cancer and its treatment among survivors of various cancer types. Clinicians can redirect survivors to a relevant healthcare provider or program to target cognitive problems.
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- 2021
5. Brain areas involved in urinary urge sensation using 7 Tesla functional magnetic resonance imaging of the human brain
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Gommert van Koeveringe, Jamie Drossaerts, J. Van Den Hurk, and Mohammad S. Rahnama'i
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Pathology ,medicine.medical_specialty ,medicine.anatomical_structure ,medicine.diagnostic_test ,business.industry ,Urology ,Urinary system ,Sensation ,medicine ,Human brain ,Functional magnetic resonance imaging ,business - Published
- 2017
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6. Opportunistic Diseases as Measure of Immunodeficiency in HIV Infection
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Peter Reiss, P. J. van den Hurk, P. T. A. Schellekens, J. W. Mulder, Marijke T. L. Roos, R. Van Leeuwen, and J M Lange
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business.industry ,Human immunodeficiency virus (HIV) ,medicine ,Measure (physics) ,medicine.disease_cause ,medicine.disease ,business ,Virology ,Immunodeficiency - Published
- 2015
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7. A compact and low-weight sputtering unit for in situ investigations of thin film growth at synchrotron radiation beamlines
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J. Wernecke, J. Blume, Ann-Christin Dippel, Peter Walter, K. Pflaum, Uwe Klemradt, and J. van den Hurk
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Materials science ,business.industry ,Scattering ,Synchrotron radiation ,DESY ,Sputter deposition ,Synchrotron ,law.invention ,Optics ,law ,Sputtering ,High-energy X-rays ,ddc:530 ,Thin film ,business ,Instrumentation - Abstract
In this work, we report on a highly variable, compact, and light high-vacuum sputter deposition unit designed for in situ experiments using synchrotron radiation facilities. The chamber can be mounted at various synchrotron beamlines for scattering experiments in grazing incidence geometry. The sample position and the large exit window allow to perform x-ray experiments up to large q values. The sputtering unit is easy to mount on existing experimental setups and can be remote-controlled. In this paper, we describe in detail the design and the performance of the new sputtering chamber and present the installation of the apparatus at different 3rd generation light sources. Furthermore, we describe the different measurement options and present some selected results. The unit has been successfully commissioned and is now available for users at PETRA III at DESY.
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- 2015
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8. Non-contraceptive use of the levonorgestrel-releasing intrauterine system
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Shaughn O'Brien and Peter J van den Hurk
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medicine.medical_specialty ,Contraceptive use ,Obstetrics ,business.industry ,medicine ,Levonorgestrel ,business ,medicine.drug - Published
- 1999
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9. Simulation of polarity independent RESET in electrochemical metallization memory cells
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Ilia Valov, Stephan Menzel, N. Adler, Stefan Tappertzhofen, J. van den Hurk, and Rainer Waser
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Non-volatile memory ,Protein filament ,Thermal conductivity ,Materials science ,Computer simulation ,Electronic countermeasure ,business.industry ,Electrode ,Optoelectronics ,Nanotechnology ,business ,Reset (computing) ,Polarity (mutual inductance) - Abstract
Redox-based resistive switching devices are a potential candidate for future non-volatile memory. One type of these devices is the electrochemical metallization cell (ECM), which typically exhibit a bipolar operation scheme. However, at high current levels a transition to polarity independent RESET switching has been observed. This work presents a numerical simulation model of the RESET operation in ECM cells, which is capable of explaining the occurrence of polarity-independent RESET switching. The model is based on the thermally activated electrochemical dissolution of a conducting filament.
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- 2013
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10. Nanobatteries in redox-based resistive switches require extension of memristor theory
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Eike Linn, J. van den Hurk, Rainer Waser, Stefan Tappertzhofen, Sebastian Schmelzer, Florian Lentz, and Ilia Valov
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Resistive touchscreen ,Condensed Matter - Materials Science ,Multidisciplinary ,Electromotive force ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,General Physics and Astronomy ,Nanotechnology ,General Chemistry ,Memristor ,Bioinformatics ,Redox ,Article ,General Biochemistry, Genetics and Molecular Biology ,law.invention ,Resistive random-access memory ,Neuromorphic engineering ,law ,Memory cell ,ddc:500 ,Nanobatteries - Abstract
Redox-based nanoionic resistive memory cells are one of the most promising emerging nanodevices for future information technology with applications for memory, logic and neuromorphic computing. Recently, the serendipitous discovery of the link between redox-based nanoionic-resistive memory cells and memristors and memristive devices has further intensified the research in this field. Here we show on both a theoretical and an experimental level that nanoionic-type memristive elements are inherently controlled by non-equilibrium states resulting in a nanobattery. As a result, the memristor theory must be extended to fit the observed non-zero-crossing I–V characteristics. The initial electromotive force of the nanobattery depends on the chemistry and the transport properties of the materials system but can also be introduced during redox-based nanoionic-resistive memory cell operations. The emf has a strong impact on the dynamic behaviour of nanoscale memories, and thus, its control is one of the key factors for future device development and accurate modelling., The original definition of a memristor envisions a two-terminal memory device with a pinched, zero-crossing hysteresis loop. As the authors show here, an electromotive force leads to non-zero-crossing characteristics in nanoionic-type memristors, implying that the memristor definition must be amended.
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- 2013
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11. On neural integration of faces and semantics
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J. van den Hurk, Jansma, Bernadette, Formisano, Elia, Cognitive Neuroscience, and RS: FPN CN 7
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- 2013
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12. p38 inhibition and not MK2 inhibition enhances the secretion of chemokines from TNF-α activated rheumatoid arthritis fibroblast-like synoviocytes
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J, Dulos, F P G, Wijnands, J A J, van den Hurk-van Alebeek, M J H, van Vugt, J A C, Rullmann, J-J G, Schot, M W G D M, de Groot, J L, Wagenaars, R, van Ravestein-van Os, R L, Smets, P M, Vink, C L, Hofstra, R L H, Nelissen, and H, van Eenennaam
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MAP Kinase Signaling System ,Pyridines ,Tumor Necrosis Factor-alpha ,Primary Cell Culture ,Synovial Membrane ,Imidazoles ,Intracellular Signaling Peptides and Proteins ,Fibroblasts ,Naphthalenes ,Protein Serine-Threonine Kinases ,p38 Mitogen-Activated Protein Kinases ,Monocytes ,Cell Line ,Up-Regulation ,Arthritis, Rheumatoid ,Humans ,Pyrazoles ,Chemokines ,Enzyme Inhibitors ,Protein Kinase Inhibitors - Abstract
For many years the p38 MAP kinase (MAPK) has been a major anti-inflammatory target for the development of an oral therapy for rheumatoid arthritis (RA). However, disappointing results from Phase II clinical studies suggest that adaptations may occur, which allow escape from blockade of the p38 pathway. In this study we investigated whether p38 inhibition mediated JNK activation represents such an escape mechanism.Interaction between the JNK and p38 pathways was studied in TNF-α stimulated THP-1 monocytes, primary macrophages and fibroblast-like synoviocytes from OA and RA patients using pharmacological inhibitors and siRNAs.TNF-α induced phosphorylation of JNK and c-Jun was sustained by p38 inhibitors in monocytes, primary macrophages and FLS. Upregulation of Mip1α, Mip1β and IL-8 mRNAs and protein were observed upon p38 inhibition. More importantly, inhibition of MK2, the substrate of p38 did not sustain JNK activation upon TNF-α activation and did not elevate Mip1α, Mip1β and IL-8 chemokines as compared to TNF-α alone. In this study, TNF-α or IL-1β induced JNK activation is sustained by p38 inhibition, resulting in enhanced chemokine secretion.Based on the suggested role of these chemokines in RA pathogenesis, the upregulation of these chemokines may provide an explanation for the lack of efficacy of p38 inhibitors in Phase II. The absence of any effect of MK2 inhibition in our models on this mechanism, while coming with similar efficacy on blocking p38, provides support for further investigations to reveal the potential of MK2 inhibition as a novel treatment of RA.
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- 2012
13. Scalp cooling for hair preservation and associated characteristics in 1411 chemotherapy patients - Results of the Dutch Scalp Cooling Registry
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Lonneke V. van de Poll-Franse, Jan Willem Coebergh, Corina J. van den Hurk, Johan W.R. Nortier, Mijke Peerbooms, and W.P.M. Breed
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Adult ,Male ,medicine.medical_specialty ,Side effect ,Adolescent ,medicine.medical_treatment ,Antineoplastic Agents ,Young Adult ,Hypothermia, Induced ,Neoplasms ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Registries ,Aged ,Aged, 80 and over ,Chemotherapy ,Scalp ,integumentary system ,business.industry ,food and beverages ,Chemotherapy induced alopecia ,Alopecia ,Hematology ,General Medicine ,Middle Aged ,Prognosis ,Surgery ,Cancer treatment ,Oncology ,Patient Satisfaction ,Scalp cooling ,Female ,business - Abstract
Chemotherapy-induced alopecia is a frequently occurring side effect of cancer treatment with a high psychological impact which can be prevented by scalp cooling. With this multi-centre patient series we estimated the results of scalp cooling for currently used chemotherapies to provide patient information and we identified characteristics associated with the results.The Dutch Scalp Cooling Registry collected data on scalp-cooled patients in 28 Dutch hospitals. Nurses and patients completed questionnaires on patients, chemotherapy and scalp cooling characteristics. Logistic regression analysis was used to examine associated characteristics of the scalp cooling result.Overall, 50% of the 1411 scalp-cooled patients did not wear a head cover during their last chemotherapy session. Patients were satisfied with the results in 8% of cases after TAC chemotherapy and up to 95% after paclitaxel treatment. Besides type of chemotherapy, higher dose and shorter infusion time, older age, female gender and non-West-European type of hair significantly increased the proportion head cover use. Hair length, quantity, chemical manipulation (dyeing, waving, colouring), wetting hair before scalp cooling, and treatment with chemotherapy ever before did not influence the degree of head covering among patients.Scalp cooling results as recorded in this open patient registry were positive for most regimens, justifying it's use by all eligible patients, except for those needing TAC. Lengthening infusion time may improve the results.
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- 2012
14. What's behind a face: person context coding in fusiform face area as revealed by multivoxel pattern analysis
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Francesco Gentile, Bernadette M. Jansma, J. van den Hurk, Cognitive Neuroscience, and RS: FPN CN 7
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Male ,Dissociation (neuropsychology) ,Cognitive Neuroscience ,media_common.quotation_subject ,Cellular and Molecular Neuroscience ,Young Adult ,Face perception ,Artificial Intelligence ,Image Interpretation, Computer-Assisted ,Personality ,Humans ,Levels-of-processing effect ,Categorical variable ,media_common ,Communication ,Brain Mapping ,business.industry ,Fusiform face area ,Magnetic Resonance Imaging ,Temporal Lobe ,Statistical classification ,Pattern Recognition, Visual ,Face ,Female ,Psychology ,business ,Algorithms ,Cognitive psychology ,Coding (social sciences) - Abstract
The identification of a face comprises processing of both visual features and conceptual knowledge. Studies showing that the fusiform face area (FFA) is sensitive to face identity generally neglect this dissociation. The present study is the first that isolates conceptual face processing by using words presented in a person context instead of faces. The design consisted of 2 different conditions. In one condition, participants were presented with blocks of words related to each other at the categorical level (e.g., brands of cars, European cities). The second condition consisted of blocks of words linked to the personality features of a specific face. Both conditions were created from the same 8 x 8 word matrix, thereby controlling for visual input across conditions. Univariate statistical contrasts did not yield any significant differences between the 2 conditions in FFA. However, a machine learning classification algorithm was able to successfully learn the functional relationship between the 2 contexts and their underlying response patterns in FFA, suggesting that these activation patterns can code for different semantic contexts. These results suggest that the level of processing in FFA goes beyond facial features. This has strong implications for the debate about the role of FFA in face identification.
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- 2011
15. HESS Opinions 'a perspective on isotope versus non-isotope approaches to determine the contribution of transpiration to total evaporation'
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Sutanto, S. J. Van Den Hurk, B. Dirmeyer, P. A. Seneviratne, S. I. Röckmann, T. Trenberth, K. E. Blyth, E. M. Wenninger, J. Hoffmann, G. and Sutanto, S. J. Van Den Hurk, B. Dirmeyer, P. A. Seneviratne, S. I. Röckmann, T. Trenberth, K. E. Blyth, E. M. Wenninger, J. Hoffmann, G.
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Current techniques to disentangle the evaporative fluxes from the continental surface into a contribution evaporated from soils and canopy, or transpired by plants, are under debate. Many isotope-based studies show that transpiration contributes generally more than 70% to the total evaporation, while other isotope-independent techniques lead to considerably smaller transpiration fractions. This paper provides a perspective on isotope-based versus non-isotope-based partitioning studies. Some partitioning results from isotope-based methods, hydrometric measurements, and modeling are presented for comparison. Moreover, the methodological aspects of the partitioning analysis are considered, including their limitations, and explanations of possible discrepancies between the methods are discussed. We suggest sources of systematic error that may lead to biases in the results, e.g., instruments inaccuracy, assumptions used in analyses, and calibration parameters. A number of comparison studies using isotope-based methods and hydrometric measurements in the same plants and climatic conditions are consistent within the errors; however, models tend to produce lower transpiration fractions. The relatively low transpiration fraction in current state-of-the-art land-surface models calls for a reassessment of the skill of the underlying model parameterizations. The scarcity of global evaporation data makes calibration and validation of global isotope-independent and isotope-based results difficult. However, isotope-enabled land-surface and global climate modeling studies allow for the evaluation of the parameterization of land-surface models by comparing the computed water isotopologue signals in the atmosphere with the available remote sensing and flux-based data sets. Future studies that allow for this evaluation could provide a better understanding of the hydrological cycle in vegetated regions.
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- 2014
16. A concept for source decoding in digital video broadcast applications
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J. van den Hurk and P. Frencken
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business.industry ,Computer science ,Video capture ,Digital video ,Data_CODINGANDINFORMATIONTHEORY ,Video processing ,Conditional access ,Digital audio broadcasting ,Embedded system ,Digital Video Broadcasting ,Digital television ,business ,Transform coding ,Composite video - Abstract
ICs for a full-featured "plug and play" MPEG2 digital video broadcast (DVB) source decoder for implementation in DVB integrated receiver decoders (IRDs) are presented. The ICs perform descrambling, demultiplexing, audio decompression, video decompression, composite video encoding as well as external interfacing. In addition to microcontroller-related memory, the source decoder requires only 16 Mbits of decompression memory. Only a minimum of peripheral hardware is required. Driver software support requirements are moderate. A microcontroller is only required to handle conditional access information, program specific information, and audio/video synchronization.
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- 2005
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17. System level design, a VHDL based approach
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J. van den Hurk and E. Dilling
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- 2002
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18. Oto-palato-digital syndrome type I: further evidence for assignment of the locus to Xq28
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A. Hanauer, B. Le Marec, Sylvie Odent, Valérie Biancalana, and J. A. M. J. van den Hurk
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Male ,Genetics ,X Chromosome ,Syndrome type ,Genetic Linkage ,Hearing Loss, Conductive ,Mutant gene ,Locus (genetics) ,Syndrome ,Biology ,Human genetics ,Pedigree ,Xq28 ,Cleft Palate ,Conduction deafness ,Intellectual Disability ,Humans ,Abnormalities, Multiple ,Female ,Gene ,Genetics (clinical) ,X chromosome - Abstract
The oto-palato-digital syndrome (OPD) is a rare X-linked disease with diagnostic skeletal features, conduction deafness, cleft palate and mild mental retardation. Differences in clinical presentation between families have led investigators to classify OPD into two subtypes: type I and type II. A linkage study performed in one family segregating for OPD I has recently suggested linkage to three marker loci: DXS15, DXS52 at Xq28, and DXS86 at Xq26. We have investigated an additional OPD I family for linkage by using distal chromosome Xq DNA probes. The linkage data and the analysis of recombination events that have occurred in this family excluded, definitively, the Xq26 region for OPD I, and provide further support for mapping the mutant gene close to the cluster of tightly linked markers DXS15, DXS52 and DXS305 at Xq28.
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- 1991
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19. PCR-based DNA fingerprinting discriminates between different biotypes of Yersinia enterocolitica
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P T, Odinot, J F, Meis, P J, van den Hurk, J A, Hoogkamp-Korstanje, and W J, Melchers
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DNA, Bacterial ,Base Sequence ,Genotype ,Yersinia Infections ,DNA Fingerprinting ,Polymerase Chain Reaction ,Bacterial Typing Techniques ,Random Amplified Polymorphic DNA Technique ,Seroepidemiologic Studies ,Humans ,Serotyping ,DNA Primers ,Repetitive Sequences, Nucleic Acid ,Yersinia enterocolitica - Published
- 1995
20. Acquisition and generalization of social behaviors in language-disabled deaf adolescents
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Pieter C. Cduker, Eef J. Rasing, Coninx F, and Ardine J. van den Hurk
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Adult ,Male ,050103 clinical psychology ,Adolescent ,Hearing loss ,Deafness ,Severity of Illness Index ,Residential Facilities ,Developmental psychology ,Arts and Humanities (miscellaneous) ,Behavior Therapy ,Social validity ,Generalization (learning) ,Developmental and Educational Psychology ,medicine ,Humans ,0501 psychology and cognitive sciences ,Language disorder ,Social Behavior ,Generality ,Language Disorders ,05 social sciences ,Follow up studies ,050301 education ,Middle Aged ,medicine.disease ,Clinical Psychology ,Multiple baseline design ,Female ,medicine.symptom ,Psychology ,0503 education ,Social behavior ,Follow-Up Studies - Abstract
In the present study, two experiments were conducted in which the effectiveness of a training package was assessed on the acquisition and generalization of five social behaviors with language-disabled and severe language-disabled deaf adolescents. The training package encom-passed modeling, self-monitoring, self-reinforcement, and mediator-directed supervision and feedback. Procedures to promote generality of effects and social validity of the procedures were used as well. Target behaviors were Initiating Interaction, Turn Waiting, Keeping to the Subject, Communicating Orally, and Using Correct Sentences. Data were collected within a multiple baseline design across behaviors. Results indicated that the training package was effective in improving the performance of all participants. However, increases in percentage of appropriate target behaviors were more substantial for the language-disabled deaf adolescents than for the severely language-disabled deaf adolescents. Maintenance of effects was demonstrated as well.
- Published
- 1994
21. Effect of infection with hemorrhagic enteritis virus on susceptibility of turkeys to Escherichia coli
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J, van den Hurk, B J, Allan, C, Riddell, T, Watts, and A A, Potter
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Turkeys ,Injections, Intravenous ,Coronavirus, Turkey ,Animals ,Enteritis, Transmissible, of Turkeys ,Disease Susceptibility ,Escherichia coli Infections ,Poultry Diseases - Abstract
The present study was designed to investigate hemorrhagic enteritis virus (HEV) as a predisposing factor influencing the susceptibility of young turkeys to Escherichia coli infections. In addition, the pathologic changes caused by administration of E. coli by various routes were compared. Following oral infection with HEV, groups of turkeys were inoculated with various doses of pathogenic E. coli by intravenous (IV), intra-air sac (IA), or intratracheal (IT) routes. A synergistic effect was observed in birds that were exposed to a combined HEV-E. coli challenge, resulting in higher mortality than that caused by either pathogen alone. This synergy was more evident when the bacteria were administered by the IT route than when it was administered by the two other routes. Turkeys infected with HEV and then inoculated IT with E. coli O78 had higher mortality (61%) and higher occurrence of gross body lesions (74%) than birds given E. coli alone (0% mortality and 16% gross lesions). After E. coli inoculation by the IA and IT routes, lesions observed were mainly pericarditis, perihepatitis, lung and air-sac lesions, splenic enlargement, and occasional arthritis. The incidence of lesions was affected by HEV exposure. In contrast, IV inoculation with E. coli O78 usually resulted in arthritis, and its incidence was independent of previous HEV exposure. The synergistic effect between HEV and E. coli administered IT can be used as a challenge model for testing E. coli vaccines.
- Published
- 1994
22. Failure to maintain high-dose treatment regimens during long-term use of zidovudine in patients with symptomatic human immunodeficiency virus type 1 infection
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R. Van Leeuwen, Peter Reiss, J. M. A. Lange, S. A. Danner, J. K. M. Eeftinck Schattenkerk, P. J. van den Hurk, P. A. Van Der Wouw, G. J. Jobsis, Other departments, and Internal medicine
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Adult ,Male ,medicine.medical_specialty ,Time Factors ,Blood transfusion ,medicine.medical_treatment ,AIDS-related complex ,Dermatology ,Gastroenterology ,Drug Administration Schedule ,Zidovudine ,AIDS-Related Complex ,Bone Marrow ,Immunopathology ,Internal medicine ,hemic and lymphatic diseases ,Humans ,Medicine ,Aged ,Retrospective Studies ,Dose Modification ,Acquired Immunodeficiency Syndrome ,Leukopenia ,business.industry ,Retrospective cohort study ,Drug Tolerance ,Middle Aged ,medicine.disease ,Long-Term Care ,Surgery ,Infectious Diseases ,Toxicity ,medicine.symptom ,business ,Research Article ,medicine.drug - Abstract
Long-term tolerance of zidovudine treatment was retrospectively analysed in 97 patients with AIDS or AIDS-related complex. After one year of treatment 68% and after two years 87% of the patients had had at least one dose adjustment during their course of therapy. Myelotoxicity was the most common cause (58% of all cases) of dose reductions and therapy interruptions (dose adjustments). At the time of the first dose adjustment 33 patients (34%) were suffering from anaemia (Hb < 6.0 g/dl), 20 patients (21%) from leukopenia (leukocytes < 1.5 x 109), and 10 patients (10%) from thrombocytopenia (thrombocytes < 75 x 109). Fifty-six patients (57%), needed one or more blood transfusions during therapy. The median time from the start of therapy to the time of the first dose adjustment was 14 (range: 2-64) weeks in patients who had a first dose adjustment because of anaemia without coexisting leukopenia or thrombocytopenia, and 37 (range: 6-85) weeks in patients who had a first dose adjustment because of leukopenia without co-existing anaemia or thrombocytopenia (p = 0.01). Peripheral blood CD4 positive lymphocyte counts ≤100/mm3, anaemia, and CDC classification IV-C1 at the start of treatment were associated with a need for an early dose modification or blood transfusion rather than the need for dose modification per se.
- Published
- 1990
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23. Lysosomal hydrolases of the epidermis
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J J van den Hurk and P.D. Mier
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chemistry.chemical_classification ,Enzyme ,integumentary system ,Biochemistry ,Epidermis (botany) ,Chemistry ,Dermatology - Abstract
Seven distinct glycosidases (EC 3.2) have been characterized in guinea-pig epidermis. Their properties indicate them to be of lysosomal origin. The 'profile' of the epidermal glycosidases is significantly different from that reported for whole skin, the activities of beta-galactosidase and beta-acetylglucosaminidase being very high and those of the remaining enzymes relatively low in epidermis.
- Published
- 1975
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24. Macroscopic and microscopic approximations of the stationary flow impedance of ordered stacks of spheres and the forces on them
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Th. H. J. Van Den Hurk and P. Van Der Leeden
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Pressure drop ,Materials science ,Approximations of π ,General Chemical Engineering ,General Engineering ,General Physics and Astronomy ,Reynolds number ,Mechanics ,symbols.namesake ,Classical mechanics ,Stack (abstract data type) ,Flow (mathematics) ,symbols ,SPHERES ,Physical and Theoretical Chemistry ,Anisotropy ,Electrical impedance - Abstract
The average reduced force exerted by a flow on a sphere in a systematically arranged stack of identical spheres is determined via measurements of the pressure drop. The Reynolds number is varied approximately from 10−2 to 104.
- Published
- 1968
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25. Mitotic activity and acid hydrolase levels in human epidermis following a single-dose of ultraviolet radiation
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J J van den Hurk, R.M. De Grood, P.D. Mier, H. Roelfzema, and F.W. Bauer
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Adult ,Male ,Epidermis (botany) ,biology ,Adolescent ,Chemistry ,Hydrolases ,Ultraviolet Rays ,Mitosis ,Dermatology ,Molecular biology ,Biochemistry ,biology.protein ,Humans ,Ultraviolet radiation ,Acid hydrolase ,Skin - Published
- 1977
26. Detection of Epstein-Barr virus antigens and antibodies by peroxidase-labeled specific immunoglobulins
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Charpentier G, Richard Morisset, C. Kurstak, Peter Tijssen, J van den Hurk, and Edouard Kurstak
- Subjects
Herpesvirus 4, Human ,viruses ,Fluorescent Antibody Technique ,medicine.disease_cause ,Immunofluorescence ,Antibodies, Viral ,Immunoglobulin G ,Cell Line ,Immunoenzyme Techniques ,Capsid ,Antigen ,immune system diseases ,hemic and lymphatic diseases ,Virology ,otorhinolaryngologic diseases ,medicine ,Humans ,Antigens, Viral ,Cell Nucleus ,biology ,medicine.diagnostic_test ,Immunoperoxidase ,Antibody titer ,virus diseases ,Nasopharyngeal Neoplasms ,medicine.disease ,Epstein–Barr virus ,Molecular biology ,Burkitt Lymphoma ,Infectious Diseases ,biology.protein ,Antibody ,Burkitt's lymphoma - Abstract
Detection of the Epstein-Barr (EBV) antigens, early antigen (EA), viral capsid antigen (VCA), and nuclear antigen (EBNA) by the indirect immunoperoxidase technique was highly sensitive. Antibody titers to EBNA, EA, and VCA were determined in more than 25 sera of patients with Burkitt lymphoma (BL), nasopharyngeal carcinoma (NPC), or normal persons. A good correlation between the titers of these antigens was obtained by the immunoperoxidase and immunofluorescence methods. The indirect (anti-IgG) immunoperoxidase technique for the detection of EBNA is, in contrast to the indirect immunofluorescence method, highly sensitive. EBNA was associated with the chromosomes in cells arrested in the metaphase with colchicine.
- Published
- 1978
27. Lysosomal hydrolases of the epidermis. 4. Overall profile in comparison with dermis and other tissues
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P D, Mier and J J, Van Den Hurk
- Subjects
Hydrolases ,Acid Phosphatase ,Guinea Pigs ,Animals ,Humans ,Cattle ,Haplorhini ,Rabbits ,Lysosomes ,Skin - Abstract
The activities of fifteen acid hydrolases have been measured in seven tissues of the guinea-pig; fourteen of these were also assayed in the epidermis of four other mammalian species. The most striking finding was that the proportion of acid phosphatase was consistently much higher in epidermis than in the other tissues investigated.
- Published
- 1976
28. Lysosomal hydrolases of the epidermis. 2. Ester hydrolases
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P D, Mier and J J, van den Hurk
- Subjects
Kinetics ,Chondro-4-Sulfatase ,Hydrolases ,Professional Issues ,Acid Phosphatase ,Guinea Pigs ,Animals ,Hydrogen-Ion Concentration ,Pyrophosphatases ,Lysosomes ,Carboxylic Ester Hydrolases ,Cerebroside-Sulfatase ,Skin - Abstract
Capacity and demand theory suggests that the presence of a queue is not necessarily an indication of a shortage of capacity in a system. It is much more likely that either there is a demand and capacity variation that creates queues or there is a delay designed into the system. A shortage of capacity is only really indicated where a backlog is not stable and continues to grow. In this article, data are taken from one NHS trust that provides evidence for a continually growing backlog for follow-up outpatient services. It is believed that these data are representative of most locations within the NHS in England and therefore suggest an immediate shortage in effective follow-up capacity. To avoid compromise to patient care, the problem will have to be addressed before the situation becomes unmanageable. The paper highlights options to reduce or deflect demand or to increase effective capacity.
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- 1975
29. Corrigendum to "More complex than you might think: Neural representations of food reward value in obesity" [Appetite 178 (2022) 106164].
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Pimpini L, Kochs S, Frannsen S, van den Hurk J, Valente G, Roebroeck A, Jansen A, and Roefs A
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- 2023
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30. It is a matter of perspective: Attentional focus rather than dietary restraint drives brain responses to food stimuli.
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Kochs S, Franssen S, Pimpini L, van den Hurk J, Valente G, Roebroeck A, Jansen A, and Roefs A
- Subjects
- Female, Humans, Brain, Energy Intake, Food Preferences, Cues, Magnetic Resonance Imaging, Food, Diet
- Abstract
Brain responses to food are thought to reflect food's rewarding value and to fluctuate with dietary restraint. We propose that brain responses to food are dynamic and depend on attentional focus. Food pictures (high-caloric/low-caloric, palatable/unpalatable) were presented during fMRI-scanning, while attentional focus (hedonic/health/neutral) was induced in 52 female participants varying in dietary restraint. The level of brain activity was hardly different between palatable versus unpalatable foods or high-caloric versus low-caloric foods. Activity in several brain regions was higher in hedonic than in health or neutral attentional focus (p < .05, FWE-corrected). Palatability and calorie content could be decoded from multi-voxel activity patterns (p < .05, FDR-corrected). Dietary restraint did not significantly influence brain responses to food. So, level of brain activity in response to food stimuli depends on attentional focus, and may reflect salience, not reward value. Palatability and calorie content are reflected in patterns of brain activity., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2023. Published by Elsevier Inc.)
- Published
- 2023
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31. Sensory brain activation during rectal balloon distention: a pilot study in healthy volunteers to assess safety and feasibility at 1.5T.
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Assmann R, Rutten S, van den Hurk J, Assmann SL, Janssen P, Bouvy N, Melenhorst J, and Breukink S
- Subjects
- Humans, Pilot Projects, Healthy Volunteers, Feasibility Studies, Rectum diagnostic imaging, Rectum physiology, Brain diagnostic imaging
- Abstract
Objective: Although increasing evidence suggests a central mechanism of action for sacral neuromodulation, the exact mechanism remains unclear. We set up a scanning paradigm to measure brain activation related to various stages of rectal filling using rectal balloon distention., Materials and Methods: Six healthy volunteers underwent rectal balloon distention during MRI scanning at a 1.5T scanner with a Tx/Rx head coil. MR images were collected at four levels of distention: empty balloon (EB), first sensation volume (FSV), desire to defecate volume (DDV), maximum tolerable volume (MTV). Data were analyzed using BrainVoyager 20.4. Whole brain and ROI-based fixed-effects general linear model analyses were performed on the fMRI time-course data from all participants., Results: Rectal filling until FSV evoked the most blood-oxygen-level-dependent responses in several clusters throughout the cortex, followed by the responses evoked by rectal filling until DDV. Interestingly, rectal filling until MTV evoked negative responses compared to baseline throughout the cortex. No negative side effects were found., Discussion: This study shows that a standardized paradigm for functional MRI combined with rectal filling is feasible and safe in healthy volunteers and is ready to be used in fecal incontinent patients to assess whether their brain activity differs from healthy controls., (© 2022. The Author(s).)
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- 2023
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32. Assessment of Brainstem Functional Organization in Healthy Adults and Overactive Bladder Patients Using Ultra-High Field fMRI.
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Fernández Chadily S, de Rijk MM, Janssen JMW, van den Hurk J, and van Koeveringe GA
- Abstract
The pathophysiological mechanisms of overactive bladder syndrome (OAB) remain largely unknown, with major involvement of the central nervous system (CNS). The periaqueductal gray (PAG) is a brainstem area which is indicated to play an essential role in bidirectional communication between the bladder and the CNS. We aimed to assess consistency of PAG functional organization across different bladder sensory states in OAB patients. We propose, that PAG functional organization patterns across sensory states will differ between controls and OAB patients. We analyzed fMRI scans at 7 Tesla from six controls and two OAB patients. The Louvain module detection algorithm was applied to parcellate the PAG in empty and full bladder states. We assessed within-subject consistency and investigated differences in this consistency between both groups. High within-subject agreement of PAG parcellations between empty and full bladder states was demonstrated in both groups. Additionally, we showed that the correlations between PAG clusters in both bladder states were significantly different in patients compared to controls ( p = 0.039). The methods introduced here offer a promising tool to assess functional organization of the PAG and understand the underlying pathology and the role of this region in OAB syndrome.
- Published
- 2023
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33. Neuroimaging in Breast Implant Illness: An fMRI Pilot Study.
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Miseré RML, Rutten S, van den Hurk J, Colaris MJL, and van der Hulst RRWJ
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- Humans, Female, Magnetic Resonance Imaging, Pilot Projects, Diffusion Tensor Imaging, Neuroimaging, Silicones adverse effects, Breast Implants adverse effects, Fibromyalgia diagnostic imaging, Fibromyalgia etiology, Chronic Pain diagnostic imaging, Chronic Pain etiology
- Abstract
Background: Some women with breast implants report systemic and cognitive symptoms known as breast implant illness (BII), which are very similar to those of fibromyalgia. Functional MRI (fMRI) has shown altered brain activity in fibromyalgia patients., Objectives: The aim of this pilot study was to investigate whether brain alterations could be observed in BII patients by fMRI., Methods: Women aged 18 to 76 with silicone breast implants for cosmetic reasons were recruited through a Dutch online BII support organization (MKS) and through the Maastricht University Medical Center. Study participants comprised 12 women with BII and 12 women without symptoms. Participants completed questionnaires regarding demographic characteristics, medical history, psychosocial complaints (Four-Dimensional Symptom Questionnaire), cognitive failure (Mini-Mental State Examination), and pain intensity and pain-related disability (Chronic Pain Grade Scale). Subsequently, brain images of all participants were obtained by resting-state fMRI and diffusion tensor imaging in a 3-T MRI scanner (Siemens Medical System, Erlangen, Germany)., Results: Eleven BII patients and 12 healthy controls were included in the analysis. Baseline characteristics were similar in the 2 groups and the mean silicone exposure was 15 years. Patients scored significantly higher than controls on both pain intensity and disability. Patients scored worse on depression, somatization, distress, and anxiety compared with asymptomatic women. Mini-Mental State Examination scores were normal. However, the analyses of both functional connectivity and structural integrity showed no significant differences between the 2 groups., Conclusions: This pilot study showed no evidence of brain alterations in BII patients. However, patients scored significantly worse on psychosocial symptoms than controls. Psychological factors appear to play an important role in BII and should be further investigated., (© 2022 The Aesthetic Society.)
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- 2023
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34. More complex than you might think: Neural representations of food reward value in obesity.
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Pimpini L, Kochs S, Franssen S, van den Hurk J, Valente G, Roebroeck A, Jansen A, and Roefs A
- Subjects
- Brain diagnostic imaging, Energy Intake, Humans, Obesity, Food, Reward
- Abstract
Obesity reached pandemic proportions and weight-loss treatments are mostly ineffective. The level of brain activity in the reward circuitry is proposed to be proportionate to the reward value of food stimuli, and stronger in people with obesity. However, empirical evidence is inconsistent. This may be due to the double-sided nature of high caloric palatable foods: at once highly palatable and high in calories (unhealthy). This study hypothesizes that, viewing high caloric palatable foods, a hedonic attentional focus compared to a health and a neutral attentional focus elicits more activity in reward-related brain regions, mostly in people with obesity. Moreover, caloric content and food palatability can be decoded from multivoxel patterns of activity most accurately in people with obesity and in the corresponding attentional focus. During one fMRI-session, attentional focus (hedonic, health, neutral) was manipulated using a one-back task with individually tailored food stimuli in 32 healthy-weight people and 29 people with obesity. Univariate analyses (p < 0.05, FWE-corrected) showed that brain activity was not different for palatable vs. unpalatable foods, nor for high vs. low caloric foods. Instead, this was higher in the hedonic compared to the health and neutral attentional focus. Multivariate analyses (MVPA) (p < 0.05, FDR-corrected) showed that palatability and caloric content could be decoded above chance level, independently of either BMI or attentional focus. Thus, brain activity to visual food stimuli is neither proportionate to the reward value (palatability and/or caloric content), nor significantly moderated by BMI. Instead, it depends on people's attentional focus, and may reflect motivational salience. Furthermore, food palatability and caloric content are represented as patterns of brain activity, independently of BMI and attentional focus. So, food reward value is reflected in patterns, not levels, of brain activity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2022
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35. Between-subject similarity of functional connectivity-based organization of the human periaqueductal gray related to autonomic processing.
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de Rijk MM, Janssen JMW, Fernández Chadily S, Birder LA, Rahnama'i MS, van Koeveringe GA, and van den Hurk J
- Abstract
The periaqueductal gray (PAG) is a brain stem area designated to play an essential role in lower urinary tract (LUT) control. Post-mortem human and animal studies have indicated that the PAG is symmetrically organized in functionally and anatomically distinct columns which are involved in sympathetic or parasympathetic autonomic control of the LUT. The current study aims to find consistency across subjects and identify homologous clusters between subjects. Here, we evaluated data from 10 female participants. During a bladder filling protocol, we ran a resting-state functional magnetic resonance imaging (fMRI) scan while participants experienced a strong desire to void. A voxel-by-voxel correlation matrix of the PAG was created and parcellated using the Louvain module detection algorithm. Resulting in a map of the PAG in which each voxel is assigned to a cluster as determined by the Louvain module detection algorithm. The spatial similarity of resulting clusters between participants was assessed by computing the Dice similarity coefficient for all cluster comparisons. Next, we designed a permutation test to create randomized parcellation maps which enabled us to statistically test the similarity values observed across participants. We observed several significantly similar clusters between subjects compared to permutations ( p ≤ 0.05). These results show that the PAG can be parcellated into distinct clusters which show a similar spatial distribution at the group level. This analysis is a crucial step to determine the agreement between in vivo PAG parcellations and the functional and anatomical columnar organization of the PAG which is known from previous research. These advancements may enable us to identify the relationship between LUT symptoms, such as urgency, and activity patterns in the PAG in normal and pathological states., Competing Interests: Author GK received consultancy fees and conducted trials for Astellas. These activities were unrelated to this work. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 de Rijk, Janssen, Fernández Chadily, Birder, Rahnama’i, van Koeveringe and van den Hurk.)
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- 2022
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36. Effects of mindset on hormonal responding, neural representations, subjective experience and intake.
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Franssen S, Jansen A, van den Hurk J, Adam T, Geyskens K, Roebroeck A, and Roefs A
- Subjects
- Craving physiology, Eating psychology, Feeding Behavior psychology, Female, Ghrelin, Glucagon-Like Peptide 1, Humans, Cacao, Chocolate
- Abstract
A person can alternate between food-related mindsets, which in turn may depend on one's emotional state or situation. Being in a certain mindset can influence food-related thoughts, but interestingly it might also affect eating-related physiological responses. The current study investigates the influence of an induced 'loss of control' mindset as compared to an 'in control' mindset on hormonal, neural and behavioural responses to chocolate stimuli. Mindsets were induced by having female chocolate lovers view a short movie during two sessions in a within-subjects design. Neural responses to visual chocolate stimuli were measured using an ultra-high field (7T) scanner. Momentary ghrelin and glucagon-like peptide 1 (GLP-1) levels were determined on five moments and were simultaneously assessed with self-reports on perceptions of chocolate craving, hunger and feelings of control. Furthermore, chocolate intake was measured using a bogus chocolate taste test. It was hypothesized that the loss of control mindset would lead to hormonal, neural and behavioural responses that prepare for ongoing food intake, even after eating, while the control mindset would lead to responses reflecting satiety. Results show that neural activity in the mesocorticolimbic system was stronger for chocolate stimuli than for neutral stimuli and that ghrelin and GLP-1 levels responded to food intake, irrespective of mindset. Self-reported craving and actual chocolate intake were affected by mindset, in that cravings and intake were higher with a loss of control mindset than with a control mindset. Interestingly, these findings suggest that physiology on the one hand (hormonal and neural responses) and behavior and subjective experience (food intake and craving) on the other hand are not in sync, are not equally affected by mindset., (Copyright © 2022. Published by Elsevier Inc.)
- Published
- 2022
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37. Ultra-high field spinal cord MRI in multiple sclerosis: Where are we standing? A literature review.
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Kreiter DJ, van den Hurk J, Wiggins CJ, Hupperts RMM, and Gerlach OHH
- Subjects
- Gray Matter diagnostic imaging, Humans, Magnetic Resonance Imaging, Retrospective Studies, Spinal Cord diagnostic imaging, Multiple Sclerosis diagnostic imaging
- Abstract
Magnetic resonance imaging (MRI) is a cornerstone in multiple sclerosis (MS) diagnostics and monitoring. Ultra-high field (UHF) MRI is being increasingly used and becoming more accessible. Due to the small diameter and mobility of the spinal cord, imaging this structure at ultra-high fields poses additional challenges compared to brain imaging. Here we review the potential benefits for the MS field by providing a literature overview of the use UHF spinal cord MRI in MS research and we elaborate on the challenges that are faced. Benefits include increased signal- and contrast-to-noise, enabling for higher spatial resolutions, which can improve MS lesion sensitivity in both the spinal white matter as well as grey matter. Additionally, these benefits can aid imaging of microstructural abnormalities in the spinal cord in MS using advanced MRI techniques like functional imaging, MR spectroscopy and diffusion-based techniques. Technical challenges include increased magnetic field inhomogeneities, distortions from physiological motion and optimalisation of sequences. Approaches including parallel imaging techniques, real time shimming and retrospective compensation of physiological motion are making it increasingly possible to unravel the potential of spinal cord UHF MRI in the context of MS research., (Copyright © 2021. Published by Elsevier B.V.)
- Published
- 2022
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38. LayNii: A software suite for layer-fMRI.
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Huber LR, Poser BA, Bandettini PA, Arora K, Wagstyl K, Cho S, Goense J, Nothnagel N, Morgan AT, van den Hurk J, Müller AK, Reynolds RC, Glen DR, Goebel R, and Gulban OF
- Subjects
- Humans, Brain diagnostic imaging, Brain physiology, Functional Neuroimaging methods, Image Processing, Computer-Assisted methods, Magnetic Resonance Imaging methods, Software
- Abstract
High-resolution fMRI in the sub-millimeter regime allows researchers to resolve brain activity across cortical layers and columns non-invasively. While these high-resolution data make it possible to address novel questions of directional information flow within and across brain circuits, the corresponding data analyses are challenged by MRI artifacts, including image blurring, image distortions, low SNR, and restricted coverage. These challenges often result in insufficient spatial accuracy of conventional analysis pipelines. Here we introduce a new software suite that is specifically designed for layer-specific functional MRI: LayNii. This toolbox is a collection of command-line executable programs written in C/C++ and is distributed opensource and as pre-compiled binaries for Linux, Windows, and macOS. LayNii is designed for layer-fMRI data that suffer from SNR and coverage constraints and thus cannot be straightforwardly analyzed in alternative software packages. Some of the most popular programs of LayNii contain 'layerification' and columnarization in the native voxel space of functional data as well as many other layer-fMRI specific analysis tasks: layer-specific smoothing, model-based vein mitigation of GE-BOLD data, quality assessment of artifact dominated sub-millimeter fMRI, as well as analyses of VASO data., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
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39. Parcellation of human periaqueductal gray at 7-T fMRI in full and empty bladder state: The foundation to study dynamic connectivity changes related to lower urinary tract functioning.
- Author
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de Rijk MM, van den Hurk J, Rahnama'i MS, and van Koeveringe GA
- Subjects
- Female, Humans, Periaqueductal Gray physiopathology, Magnetic Resonance Imaging methods, Periaqueductal Gray diagnostic imaging, Urinary Bladder diagnostic imaging
- Abstract
Aims: The periaqueductal gray (PAG) is a brain stem area involved in processing signals related to urine storage and voiding. The PAG is proposed to be responsible for projecting afferent information from the bladder to cortical and subcortical brain areas and acts as a relay station projecting efferent information from cortical and subcortical areas to the pons and spinal cord. Here, we use 7-Tesla functional magnetic resonance imaging to parcellate the PAG into functionally distinct clusters during a bladder filling protocol., Methods: We assess the similarity between parcellation results in empty and full bladder states and show how these parcellations can be used to create dynamic response profiles of connectivity changes between clusters as a function of bladder sensations., Results: For each of our six healthy female participants, we found that the agreement between at least one of the clusters in both states resulting from the parcellation procedure was higher than could be expected based on chance (p ≤ .05), and observed that these clusters are significantly organized in a symmetrical lateralized fashion (p ≤ .05). Correlations between clusters change significantly as a function of experienced sensations during bladder filling (p ≤ .05)., Conclusions: This opens new possibilities to investigate the effects of treatments of lower urinary tract symptoms on signal processing in the PAG, as well as the investigation of disease-specific bladder filling related dynamic signal processing in this small brain structure., (© 2020 The Authors. Neurourology and Urodynamics published by Wiley Periodicals LLC.)
- Published
- 2021
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40. A Probabilistic Functional Atlas of Human Occipito-Temporal Visual Cortex.
- Author
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Rosenke M, van Hoof R, van den Hurk J, Grill-Spector K, and Goebel R
- Subjects
- Adult, Brain Mapping methods, Female, Humans, Magnetic Resonance Imaging methods, Male, Occipital Lobe physiology, Visual Perception physiology, Pattern Recognition, Visual physiology, Temporal Lobe physiology, Visual Cortex physiology, Visual Pathways physiology
- Abstract
Human visual cortex contains many retinotopic and category-specific regions. These brain regions have been the focus of a large body of functional magnetic resonance imaging research, significantly expanding our understanding of visual processing. As studying these regions requires accurate localization of their cortical location, researchers perform functional localizer scans to identify these regions in each individual. However, it is not always possible to conduct these localizer scans. Here, we developed and validated a functional region of interest (ROI) atlas of early visual and category-selective regions in human ventral and lateral occipito-temporal cortex. Results show that for the majority of functionally defined ROIs, cortex-based alignment results in lower between-subject variability compared to nonlinear volumetric alignment. Furthermore, we demonstrate that 1) the atlas accurately predicts the location of an independent dataset of ventral temporal cortex ROIs and other atlases of place selectivity, motion selectivity, and retinotopy. Next, 2) we show that the majority of voxel within our atlas is responding mostly to the labeled category in a left-out subject cross-validation, demonstrating the utility of this atlas. The functional atlas is publicly available (download.brainvoyager.com/data/visfAtlas.zip) and can help identify the location of these regions in healthy subjects as well as populations (e.g., blind people, infants) in which functional localizers cannot be run., (© The Author(s) 2020. Published by Oxford University Press.)
- Published
- 2021
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41. Power of mind: Attentional focus rather than palatability dominates neural responding to visual food stimuli in females with overweight.
- Author
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Franssen S, Jansen A, van den Hurk J, Roebroeck A, and Roefs A
- Subjects
- Adult, Diet psychology, Energy Intake, Feeding Behavior physiology, Female, Food, Humans, Middle Aged, Multivariate Analysis, Obesity etiology, Overweight, Pleasure, Attention, Brain physiology, Cues, Feeding Behavior psychology, Obesity psychology, Reward, Taste
- Abstract
Research investigating neural responses to visual food stimuli has produced inconsistent results. Crucially, high-caloric palatable foods have a double-sided nature - they are often craved but are also considered unhealthy - which may have contributed to the inconsistency in the literature. Taking this double-sided nature into account in the current study, neural responses to individually tailored palatable and unpalatable high caloric food stimuli were measured, while participants' (females with overweight: n = 23) attentional focus was manipulated to be either hedonic or neutral. Notably, results showed that the level of neural activity was not significantly different for palatable than for unpalatable food stimuli. Instead, independent of food palatability, several brain regions (including regions in the mesocorticolimbic system) responded more strongly when attentional focus was hedonic than when neutral (p < 0.05, cluster-based FWE corrected). Multivariate analyses showed that food palatability could be decoded from multi-voxel patterns of neural activity (p < 0.05, FDR corrected), mostly with a hedonic attentional focus. These findings illustrate that the level of neural activity might not be proportionate to the palatability of foods, but that food palatability can be decoded from multi-voxel patterns of neural activity. Moreover, they underline the importance of considering attentional focus when measuring food-related neural responses., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2020
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42. Somatotopic mapping of the human breast using 7 T functional MRI.
- Author
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Beugels J, van den Hurk J, Peters JC, Heuts EM, Tuinder SMH, Goebel R, and van der Hulst RRWJ
- Subjects
- Adult, Female, Humans, Magnetic Resonance Imaging, Male, Young Adult, Brain Mapping, Breast physiology, Somatosensory Cortex physiology, Touch physiology, Touch Perception physiology
- Abstract
How are tactile sensations in the breast represented in the female and male brain? Using ultra high-field 7 T MRI in ten females and ten males, we demonstrate that the representation of tactile breast information shows a somatotopic organization, with cortical magnification of the nipple. Furthermore, we show that the core representation of the breast is organized according to the specific nerve architecture that underlies breast sensation, where the medial and lateral sides of one breast are asymmetrically represented in bilateral primary somatosensory cortex. Finally, gradual selectivity signatures allude to a somatotopic organization of the breast area with overlapping, but distinctive, cortical representations of breast segments. Our univariate and multivariate analyses consistently showed similar somatosensory breast representations in males and females. The findings can guide future research on neuroplastic reorganization of the breast area, across reproductive life stages, and after breast surgery., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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43. Where Are the fMRI Correlates of Phosphene Perception?
- Author
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de Graaf TA, van den Hurk J, Duecker F, and Sack AT
- Abstract
Pulses of transcranial magnetic stimulation (TMS) over occipital cortex can induce transient visual percepts called phosphenes. Phosphenes are an interesting stimulus for the study of the human visual system, constituting conscious percepts without visual inputs, elicited by neural activation beyond retinal and subcortical processing stages in the visual hierarchy. The same TMS pulses, applied at threshold intensity phosphene threshold (PT), will prompt phosphene reports on half of all trials ("P-yes") but not on the other half ("P-no"). Contrasting brain activity (P-yes > P-no) can provide unique information on neural mechanisms underlying conscious percepts, as has been demonstrated by published EEG studies. Yet to our knowledge no articles reporting analogous contrasts with functional magnetic resonance imaging (fMRI) have been published. Since it seems unlikely that such studies have never been performed, this straightforward and technically feasible idea may have been explored in multiple failed, and unpublished, attempts. Here, we argue why such unsuccessful attempts, even small-scale, best be shared. We also report our own failed attempt to find phosphene-related activity in fMRI. Threshold phosphenes are weak percepts, and their detection subjective and difficult. If fMRI correlates of phosphenes are obtainable with this contrast, small-scale ('pilot') measurements may not be sufficiently powerful to detect them. At the same time, due to the challenges and costs involved in TMS-fMRI, attempts might not often get beyond the piloting stage. We propose that the only way out of this quandary is the communication and sharing of such unsuccessful attempts and associated data.
- Published
- 2018
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44. Synchronous diversification of Sulawesi's iconic artiodactyls driven by recent geological events.
- Author
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Frantz LAF, Rudzinski A, Nugraha AMS, Evin A, Burton J, Hulme-Beaman A, Linderholm A, Barnett R, Vega R, Irving-Pease EK, Haile J, Allen R, Leus K, Shephard J, Hillyer M, Gillemot S, van den Hurk J, Ogle S, Atofanei C, Thomas MG, Johansson F, Mustari AH, Williams J, Mohamad K, Damayanti CS, Wiryadi ID, Obbles D, Mona S, Day H, Yasin M, Meker S, McGuire JA, Evans BJ, von Rintelen T, Ho SYW, Searle JB, Kitchener AC, Macdonald AA, Shaw DJ, Hall R, Galbusera P, and Larson G
- Subjects
- Animals, Base Sequence, Buffaloes genetics, DNA, Mitochondrial, Geography, Indonesia, Islands, Microsatellite Repeats, Phylogeny, Phylogeography, Swine genetics, Buffaloes classification, Genetic Speciation, Geological Phenomena, Swine classification
- Abstract
The high degree of endemism on Sulawesi has previously been suggested to have vicariant origins, dating back to 40 Ma. Recent studies, however, suggest that much of Sulawesi's fauna assembled over the last 15 Myr. Here, we test the hypothesis that more recent uplift of previously submerged portions of land on Sulawesi promoted diversification and that much of its faunal assemblage is much younger than the island itself. To do so, we combined palaeogeographical reconstructions with genetic and morphometric datasets derived from Sulawesi's three largest mammals: the babirusa, anoa and Sulawesi warty pig. Our results indicate that although these species most likely colonized the area that is now Sulawesi at different times (14 Ma to 2-3 Ma), they experienced an almost synchronous expansion from the central part of the island. Geological reconstructions indicate that this area was above sea level for most of the last 4 Myr, unlike most parts of the island. We conclude that emergence of land on Sulawesi (approx. 1-2 Myr) may have allowed species to expand synchronously. Altogether, our results indicate that the establishment of the highly endemic faunal assemblage on Sulawesi was driven by geological events over the last few million years., (© 2018 The Authors.)
- Published
- 2018
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45. Nicotine deprivation elevates neural representation of smoking-related cues in object-sensitive visual cortex: a proof of concept study.
- Author
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Havermans A, van Schayck OCP, Vuurman EFPM, Riedel WJ, and van den Hurk J
- Subjects
- Adult, Brain Mapping, Female, Humans, Magnetic Resonance Imaging, Male, Proof of Concept Study, Smoking physiopathology, Smoking psychology, Substance Withdrawal Syndrome physiopathology, Visual Cortex physiopathology, Young Adult, Attention physiology, Cues, Nicotine adverse effects, Smoking drug therapy, Substance Withdrawal Syndrome diagnostic imaging, Visual Cortex diagnostic imaging
- Abstract
Objective: In the current study, we use functional magnetic resonance imaging (fMRI) and multi-voxel pattern analysis (MVPA) to investigate whether tobacco addiction biases basic visual processing in favour of smoking-related images. We hypothesize that the neural representation of smoking-related stimuli in the lateral occipital complex (LOC) is elevated after a period of nicotine deprivation compared to a satiated state, but that this is not the case for object categories unrelated to smoking., Methods: Current smokers (≥10 cigarettes a day) underwent two fMRI scanning sessions: one after 10 h of nicotine abstinence and the other one after smoking ad libitum. Regional blood oxygenated level-dependent (BOLD) response was measured while participants were presented with 24 blocks of 8 colour-matched pictures of cigarettes, pencils or chairs. The functional data of 10 participants were analysed through a pattern classification approach., Results: In bilateral LOC clusters, the classifier was able to discriminate between patterns of activity elicited by visually similar smoking-related (cigarettes) and neutral objects (pencils) above empirically estimated chance levels only during deprivation (mean = 61.0%, chance (permutations) = 50.0%, p = .01) but not during satiation (mean = 53.5%, chance (permutations) = 49.9%, ns.). For all other stimulus contrasts, there was no difference in discriminability between the deprived and satiated conditions., Conclusion: The discriminability between smoking and non-smoking visual objects was elevated in object-selective brain region LOC after a period of nicotine abstinence. This indicates that attention bias likely affects basic visual object processing.
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- 2017
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46. Development of visual category selectivity in ventral visual cortex does not require visual experience.
- Author
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van den Hurk J, Van Baelen M, and Op de Beeck HP
- Subjects
- Acoustic Stimulation, Adult, Blindness diagnostic imaging, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Temporal Lobe diagnostic imaging, Visual Cortex diagnostic imaging, Visual Pathways diagnostic imaging, Young Adult, Blindness physiopathology, Temporal Lobe physiology, Visual Cortex physiology, Visual Pathways physiology
- Abstract
To what extent does functional brain organization rely on sensory input? Here, we show that for the penultimate visual-processing region, ventral-temporal cortex (VTC), visual experience is not the origin of its fundamental organizational property, category selectivity. In the fMRI study reported here, we presented 14 congenitally blind participants with face-, body-, scene-, and object-related natural sounds and presented 20 healthy controls with both auditory and visual stimuli from these categories. Using macroanatomical alignment, response mapping, and surface-based multivoxel pattern analysis, we demonstrated that VTC in blind individuals shows robust discriminatory responses elicited by the four categories and that these patterns of activity in blind subjects could successfully predict the visual categories in sighted controls. These findings were confirmed in a subset of blind participants born without eyes and thus deprived from all light perception since conception. The sounds also could be decoded in primary visual and primary auditory cortex, but these regions did not sustain generalization across modalities. Surprisingly, although not as strong as visual responses, selectivity for auditory stimulation in visual cortex was stronger in blind individuals than in controls. The opposite was observed in primary auditory cortex. Overall, we demonstrated a striking similarity in the cortical response layout of VTC in blind individuals and sighted controls, demonstrating that the overall category-selective map in extrastriate cortex develops independently from visual experience., Competing Interests: The authors declare no conflict of interest.
- Published
- 2017
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47. S1 domain of the porcine epidemic diarrhea virus spike protein as a vaccine antigen.
- Author
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Makadiya N, Brownlie R, van den Hurk J, Berube N, Allan B, Gerdts V, and Zakhartchouk A
- Subjects
- Adjuvants, Immunologic administration & dosage, Animals, Antibodies, Neutralizing analysis, Antibodies, Viral analysis, Antigens, Viral genetics, Colostrum immunology, Coronavirus Infections pathology, Coronavirus Infections prevention & control, Enzyme-Linked Immunosorbent Assay, Female, Injections, Intramuscular, Neutralization Tests, Porcine epidemic diarrhea virus genetics, Pregnancy, Serum immunology, Spike Glycoprotein, Coronavirus genetics, Swine, Treatment Outcome, Vaccines, Subunit administration & dosage, Vaccines, Subunit genetics, Vaccines, Subunit immunology, Vaccines, Synthetic administration & dosage, Vaccines, Synthetic genetics, Vaccines, Synthetic immunology, Viral Vaccines administration & dosage, Viral Vaccines genetics, Antigens, Viral immunology, Coronavirus Infections veterinary, Porcine epidemic diarrhea virus immunology, Spike Glycoprotein, Coronavirus immunology, Viral Vaccines immunology
- Abstract
Background: Porcine epidemic diarrhea virus (PEDV) is a highly contagious virus infecting pigs of all ages with high morbidity and mortality among newborn piglets. Currently, there is no effective vaccine available to protect the pigs from PEDV. The N-terminal subunit of spike protein (S1) is responsible for virus binding to the cellular receptor and contains a number of neutralizing antibody epitopes. Thus, we expressed and produced recombinant S1 protein to protect newborn piglets by immunization of sows., Methods: Affinity tagged PEDV S1 protein was expressed in a secretory form in yeast, insect and mammalian cells to identify the most suitable production system. Purified recombinant protein was analysed by SDS-PAGE, Western blot and deglycosylation assay. A pregnant sow was intramuscularly immunized three times with adjuvanted recombinant protein prior to farrowing. PEDV-specific immune responses in sera and colostrum of the sow and piglets were assayed by ELISA and virus neutralization assays. Piglets were challenged orally with PEDV, and clinical parameters were monitored for 6 days post-challenge., Results and Conclusion: Of three eukaryotic expression systems tested (yeast, insect-cell, and mammalian), expression by HEK-293 T cells gave the highest yield of protein that was N-glycosylated and was the most appropriate candidate for vaccination. Administration of the subunit vaccine in a sow resulted in induction of S1-specific IgG and IgA that were passively transferred to the suckling piglets. Also, high virus neutralization titres were observed in the serum of the vaccinated sow and its piglets. After PEDV challenge, piglets born to the vaccinated sow exhibited less severe signs of disease and significantly lower mortality compared to the piglets of a control sow. However, there were no significant differences in diarrhea, body weight and virus shedding. Thus, vaccination with S1 subunit vaccine failed to provide complete protection to suckling piglets after challenge exposure, and further improvements are needed for the development of a subunit vaccine that fully protects against PEDV infection.
- Published
- 2016
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48. The Search for the Face of the Visual Homunculus.
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van den Hurk J, Pegado F, Martens F, and Op de Beeck HP
- Subjects
- Brain blood supply, Humans, Magnetic Resonance Imaging, Brain physiology, Brain Mapping, Face, Pattern Recognition, Visual physiology
- Abstract
The functional organization within face-sensitive regions in the brain is largely unknown. A new fMRI study provided evidence that a face-selective region contains neighboring patches of cortex that encode physically neighboring face features. We suggest that multiple mechanisms should be considered for a full understanding of the functional maps in face-selective cortex., (Copyright © 2015. Published by Elsevier Ltd.)
- Published
- 2015
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49. Affected functional networks associated with sentence production in classic galactosemia.
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Timmers I, van den Hurk J, Hofman PA, Zimmermann LJ, Uludağ K, Jansma BM, and Rubio-Gozalbo ME
- Subjects
- Adolescent, Case-Control Studies, Child, Female, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Oxygen blood, Brain blood supply, Brain pathology, Brain Mapping, Galactosemias complications, Galactosemias pathology, Language Disorders etiology
- Abstract
Patients with the inherited metabolic disorder classic galactosemia have language production impairments in several planning stages. Here, we assessed potential deviations in recruitment and connectivity across brain areas responsible for language production that may explain these deficits. We used functional magnetic resonance imaging (fMRI) to study neural activity and connectivity while participants carried out a language production task. This study included 13 adolescent patients and 13 age- and gender-matched healthy controls. Participants passively watched or actively described an animated visual scene using two conditions, varying in syntactic complexity (single words versus a sentence). Results showed that patients recruited additional and more extensive brain regions during sentence production. Both groups showed modulations with syntactic complexity in left inferior frontal gyrus (IFG), a region associated with syntactic planning, and in right insula. In addition, patients showed a modulation with syntax in left superior temporal gyrus (STG), whereas the controls did not. Further, patients showed increased activity in right STG and right supplementary motor area (SMA). The functional connectivity data showed similar patterns, with more extensive connectivity with frontal and motor regions, and restricted and weaker connectivity with superior temporal regions. Patients also showed higher baseline cerebral blood flow (CBF) in right IFG and trends towards higher CBF in bilateral STG, SMA and the insula. Taken together, the data demonstrate that language abnormalities in classic galactosemia are associated with specific changes within the language network. These changes point towards impairments related to both syntactic planning and speech motor planning in these patients., (Copyright © 2015 Elsevier B.V. All rights reserved.)
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- 2015
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50. Proteomic analysis of purified turkey adenovirus 3 virions.
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Kumar P, van den Hurk J, Ayalew LE, Gaba A, and Tikoo SK
- Subjects
- Adenoviridae Infections genetics, Adenoviridae Infections virology, Animals, Blotting, Western veterinary, Chromatography, Liquid veterinary, Poultry Diseases virology, Proteome metabolism, Proteomics, Siadenovirus metabolism, Tandem Mass Spectrometry veterinary, Viral Proteins metabolism, Viral Structural Proteins genetics, Viral Structural Proteins metabolism, Adenoviridae Infections veterinary, Poultry Diseases genetics, Proteome genetics, Siadenovirus genetics, Turkeys, Viral Proteins genetics
- Abstract
Turkey adenovirus 3 (TAdV-3) causes high mortality and significant economic losses to the turkey industry. However, little is known about the molecular determinants required for viral replication and pathogenesis. Moreover, TAdV-3 does not grow well in cell culture, thus detailed structural studies of the infectious particle is particularly challenging. To develop a better understanding of virus-host interactions, we performed a comprehensive proteomic analysis of proteinase K treated purified TAdV-3 virions isolated from spleens of infected turkeys, by utilizing one-dimensional liquid chromatography mass spectrometry. Our analysis resulted in the identification of 13 viral proteins associated with TAdV-3 virions including a novel uncharacterized TaV3gp04 protein. Further, we detected 18 host proteins in purified virions, many of which are involved in cell-to cell spread, cytoskeleton dynamics and virus replication. Notably, seven of these host proteins have not yet been reported to be present in any other purified virus. In addition, five of these proteins are known antiviral host restriction factors. The availability of reagents allowed us to identify two cellular proteins (collagen alpha-1 (VI) chain and haemoglobin) in the purified TAdV-3 preparations. These results represent the first comprehensive proteomic profile of TAdV-3 and may provide information for illustrating TAdV-3 replication and pathogenesis.
- Published
- 2015
- Full Text
- View/download PDF
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