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D'Agostini M, Burger AM, Franssen M, Perkovic A, Claes S, von Leupoldt A, Murphy PR, Van Diest I. Short bursts of transcutaneous auricular vagus nerve stimulation enhance evoked pupil dilation as a function of stimulation parameters. Cortex 2023; 159:233-253. [PMID: 36640622 DOI: 10.1016/j.cortex.2022.11.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/28/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022]
Abstract
Transcutaneous auricular vagus nerve stimulation (taVNS) is a neurostimulatory technique hypothesised to enhance central noradrenaline. Currently, there is scarce evidence in support of a noradrenergic mechanism of taVNS and limited knowledge on its stimulation parameters (i.e., intensity and pulse width). Therefore, the present study aimed to test whether taVNS enhances pupil dilation, a noradrenergic biomarker, as a function of stimulation parameters. Forty-nine participants received sham (i.e., left ear earlobe) and taVNS (i.e., left ear cymba concha) stimulation in two separate sessions, in a counterbalanced order. We administered short bursts (5s) of seven stimulation settings varying as a function of pulse width and intensity and measured pupil size in parallel. Each stimulation setting was administered sixteen times in separate blocks. We expected short bursts of stimulation to elicit phasic noradrenergic activity as indexed by event-related pupil dilation and event-related temporal derivative. We hypothesised higher stimulation settings, quantified as the total charge per pulse (pulse width x intensity), to drive greater event-related pupil dilation and temporal derivative in the taVNS compared to sham condition. Specifically, we expected stimulation settings in the taVNS condition to be associated with a linear increase in event-related pupil dilation and temporal derivative. We found stimulation settings to linearly increase both pupil measures. In line with our hypothesis, the observed dose-dependent effect was stronger in the taVNS condition. We also found taVNS to elicit more intense and unpleasant sensations than sham stimulation. These results support the hypothesis of a noradrenergic mechanism of taVNS. However, future studies should disentangle whether stimulation elicited sensations mediate the effect of taVNS on evoked pupil dilation.
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Affiliation(s)
| | | | | | - Ana Perkovic
- Research Group Health Psychology, KU Leuven, Leuven, Belgium
| | - Stephan Claes
- The Mind Body Research Group, Department of Neuroscience, KU Leuven, Leuven, Belgium.
| | | | - Peter R Murphy
- Department of Psychology, Maynooth University, Co. Kildare, Ireland; Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Ireland.
| | - Ilse Van Diest
- Research Group Health Psychology, KU Leuven, Leuven, Belgium.
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Giraudier M, Ventura-Bort C, Burger AM, Claes N, D'Agostini M, Fischer R, Franssen M, Kaess M, Koenig J, Liepelt R, Nieuwenhuis S, Sommer A, Usichenko T, Van Diest I, von Leupoldt A, Warren CM, Weymar M. Modulating effect of transcutaneous auricular vagus nerve stimulation (taVNS) on salivary alpha-amylase as indirect noradrenergic marker. Brain Stimul 2023. [DOI: 10.1016/j.brs.2023.01.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
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3
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Giraudier M, Ventura-Bort C, Burger AM, Claes N, D'Agostini M, Fischer R, Franssen M, Kaess M, Koenig J, Liepelt R, Nieuwenhuis S, Sommer A, Usichenko T, Van Diest I, von Leupoldt A, Warren CM, Weymar M. Evidence for a modulating effect of transcutaneous auricular vagus nerve stimulation (taVNS) on salivary alpha-amylase as indirect noradrenergic marker: A pooled mega-analysis. Brain Stimul 2022; 15:1378-1388. [PMID: 36183953 DOI: 10.1016/j.brs.2022.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 09/22/2022] [Accepted: 09/22/2022] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has received tremendous attention as a potential neuromodulator of cognitive and affective functions, which likely exerts its effects via activation of the locus coeruleus-noradrenaline (LC-NA) system. Reliable effects of taVNS on markers of LC-NA system activity, however, have not been demonstrated yet. METHODS The aim of the present study was to overcome previous limitations by pooling raw data from a large sample of ten taVNS studies (371 healthy participants) that collected salivary alpha-amylase (sAA) as a potential marker of central NA release. RESULTS While a meta-analytic approach using summary statistics did not yield any significant effects, linear mixed model analyses showed that afferent stimulation of the vagus nerve via taVNS increased sAA levels compared to sham stimulation (b = 0.16, SE = 0.05, p = 0.001). When considering potential confounders of sAA, we further replicated previous findings on the diurnal trajectory of sAA activity. CONCLUSION(S) Vagal activation via taVNS increases sAA release compared to sham stimulation, which likely substantiates the assumption that taVNS triggers NA release. Moreover, our results highlight the benefits of data pooling and data sharing in order to allow stronger conclusions in research.
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Affiliation(s)
- Manon Giraudier
- Department of Biological Psychology and Affective Science, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany.
| | - Carlos Ventura-Bort
- Department of Biological Psychology and Affective Science, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany
| | | | - Nathalie Claes
- Research Group Health Psychology, KU Leuven, Leuven, Belgium
| | | | - Rico Fischer
- Department of Psychology, University of Greifswald, Greifswald, Germany
| | | | - Michael Kaess
- University Hospital of Child and Adolescent Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland; Department of Child and Adolescent Psychiatry, Centre for Psychosocial Medicine, University of Heidelberg, Heidelberg, Germany
| | - Julian Koenig
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Cologne, Germany
| | - Roman Liepelt
- Department of General Psychology: Judgment, Decision Making, Action, Faculty of Psychology, University of Hagen (FernUniversität in Hagen), Hagen, Germany
| | - Sander Nieuwenhuis
- Institute of Psychology, Leiden University, Netherlands; Leiden Institute for Brain and Cognition, Leiden University, Netherlands
| | - Aldo Sommer
- Department of General Psychology: Judgment, Decision Making, Action, Faculty of Psychology, University of Hagen (FernUniversität in Hagen), Hagen, Germany; Department of Exercise Physiology, German Sport University Cologne, Cologne, Germany
| | - Taras Usichenko
- Department of Anesthesiology, University Medicine of Greifswald, Greifswald, Germany; Department of Anesthesia, McMaster University, Hamilton, Canada
| | - Ilse Van Diest
- Research Group Health Psychology, KU Leuven, Leuven, Belgium
| | | | - Christopher M Warren
- Emma Eccles Jones College of Education and Human Services, Utah State University, United States
| | - Mathias Weymar
- Department of Biological Psychology and Affective Science, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany; Faculty of Health Sciences Brandenburg, University of Potsdam, Potsdam, Germany.
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D'Agostini M, Burger AM, Franssen M, Claes N, Weymar M, von Leupoldt A, Van Diest I. Effects of transcutaneous auricular vagus nerve stimulation on reversal learning, tonic pupil size, salivary alpha-amylase, and cortisol. Psychophysiology 2021; 58:e13885. [PMID: 34245461 DOI: 10.1111/psyp.13885] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 04/26/2021] [Accepted: 05/25/2021] [Indexed: 12/11/2022]
Abstract
This study investigated whether transcutaneous auricular vagus nerve stimulation (taVNS) enhances reversal learning and augments noradrenergic biomarkers (i.e., pupil size, cortisol, and salivary alpha-amylase [sAA]). We also explored the effect of taVNS on respiratory rate and cardiac vagal activity (CVA). Seventy-one participants received stimulation of either the cymba concha (taVNS) or the earlobe (sham) of the left ear. After learning a series of cue-outcome associations, the stimulation was applied before and throughout a reversal phase in which cue-outcome associations were changed for some (reversal), but not for other (distractor) cues. Tonic pupil size, salivary cortisol, sAA, respiratory rate, and CVA were assessed at different time points. Contrary to our hypothesis, taVNS was not associated with an overall improvement in performance on the reversal task. Compared to sham, the taVNS group performed worse for distractor than reversal cues. taVNS did not increase tonic pupil size and sAA. Only post hoc analyses indicated that the cortisol decline was steeper in the sham compared to the taVNS group. Exploratory analyses showed that taVNS decreased respiratory rate but did not affect CVA. The weak and unexpected effects found in this study might relate to the lack of parameters optimization for taVNS and invite to further investigate the effect of taVNS on cortisol and respiratory rate.
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Affiliation(s)
| | - Andreas M Burger
- Research Group Health Psychology, KU Leuven, Leuven, Belgium.,Laboratory for Biological Psychology, KU Leuven, Leuven, Belgium
| | | | - Nathalie Claes
- Research Group Health Psychology, KU Leuven, Leuven, Belgium
| | - Mathias Weymar
- Department of Biological Psychology and Affective Science, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany.,Faculty of Health Sciences Brandenburg, University of Potsdam, Potsdam, Germany
| | | | - Ilse Van Diest
- Research Group Health Psychology, KU Leuven, Leuven, Belgium
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Van Den Houte M, Vlemincx E, Franssen M, Van Diest I, Van Oudenhove L, Luminet O. The respiratory occlusion discrimination task: A new paradigm to measure respiratory interoceptive accuracy. Psychophysiology 2021; 58:e13760. [PMID: 33438245 DOI: 10.1111/psyp.13760] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/20/2020] [Accepted: 12/15/2020] [Indexed: 02/06/2023]
Abstract
Interoception, or the sense of the internal state of the body, is hypothesized to be essential for a wide range of psychobiological processes and the development and perpetuation of several (mental) health problems. However, the study of interoceptive accuracy, the objectively measured capacity to detect or discriminate conscious bodily signals, has been hampered by the use of tasks with questionable construct validity and is often limited to studying interoception solely in the cardiac domain. We developed a novel task to measure interoceptive accuracy in the respiratory domain, the respiratory occlusion discrimination (ROD) task. In this task, interoceptive accuracy is defined as an individual's ability to detect small differences in lengths of short respiratory occlusions, assessed by means of an adaptive staircase procedure. This article describes a validation study (N = 97) aimed at investigating the internal consistency, test-retest reliability, and discriminant validity of the ROD task. The average just noticeable difference of lengths of respiratory occlusion was 74.22 ms, with large inter-individual variability (SD = 37.1 ms). The results of the validation study indicate acceptable internal consistency (Cronbach's alpha = 0.70), 1-week test-retest reliability (r = 0.53), and discriminant validity, as indicated by a lack of correlation between the ROD task and an auditory discrimination task with identical design (r = 0.18), and a weak correlation with breathing behavior (r = -0.27). The ROD task is a promising novel paradigm to study interoceptive accuracy and its role in various psychobiological processes and disorders.
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Affiliation(s)
- Maaike Van Den Houte
- Research group on Health, Emotion, Cognition, and Memory, Research Institute for Psychological Sciences, UCLouvain, Louvain-La-Neuve, Belgium.,Laboratory for Brain-Gut Axis Studies (LaBGAS), KU Leuven, Leuven, Belgium.,Fund for Scientific Research (FRS-FNRS), Belgium
| | - Elke Vlemincx
- Department of Health Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - Ilse Van Diest
- Health Psychology Research Group, KU Leuven, Leuven, Belgium
| | - Lukas Van Oudenhove
- Laboratory for Brain-Gut Axis Studies (LaBGAS), KU Leuven, Leuven, Belgium.,Cognitive & Affective Neuroscience Lab, Dartmouth College, Hanover, NH, USA
| | - Olivier Luminet
- Research group on Health, Emotion, Cognition, and Memory, Research Institute for Psychological Sciences, UCLouvain, Louvain-La-Neuve, Belgium.,Fund for Scientific Research (FRS-FNRS), Belgium
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Glogan E, Gatzounis R, Vandael K, Franssen M, Vlaeyen JWS, Meulders A. Investigating Pain-Related Avoidance Behavior using a Robotic Arm-Reaching Paradigm. J Vis Exp 2020. [PMID: 33074255 DOI: 10.3791/61717] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Avoidance behavior is a key contributor to the transition from acute pain to chronic pain disability. Yet, there has been a lack of ecologically valid paradigms to experimentally investigate pain-related avoidance. To fill this gap, we developed a paradigm (the robotic arm-reaching paradigm) to investigate the mechanisms underlying the development of pain-related avoidance behavior. Existing avoidance paradigms (mostly in the context of anxiety research) have often operationalized avoidance as an experimenter-instructed, low-cost response, superimposed on stimuli associated with threat during a Pavlovian fear conditioning procedure. In contrast, the current method offers increased ecological validity in terms of instrumental learning (acquisition) of avoidance, and by adding a cost to the avoidance response. In the paradigm, participants perform arm-reaching movements from a starting point to a target using a robotic arm, and freely choose between three different movement trajectories to do so. The movement trajectories differ in probability of being paired with a painful electrocutaneous stimulus, and in required effort in terms of deviation and resistance. Specifically, the painful stimulus can be (partly) avoided at the cost of performing movements requiring increased effort. Avoidance behavior is operationalized as the maximal deviation from the shortest trajectory on each trial. In addition to explaining how the new paradigm can help understand the acquisition of avoidance, we describe adaptations of the robotic arm-reaching paradigm for (1) examining the spread of avoidance to other stimuli (generalization), (2) modeling clinical treatment in the lab (extinction of avoidance using response prevention), as well as (3) modeling relapse, and return of avoidance following extinction (spontaneous recovery). Given the increased ecological validity, and numerous possibilities for extensions and/or adaptations, the robotic arm-reaching paradigm offers a promising tool to facilitate the investigation of avoidance behavior and to further our understanding of its underlying processes.
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Affiliation(s)
- Eveliina Glogan
- Experimental Health Psychology, Maastricht University; Research Group Health Psychology, KU Leuven
| | | | - Kristof Vandael
- Experimental Health Psychology, Maastricht University; Laboratory of Biological Psychology, KU Leuven
| | | | - Johan W S Vlaeyen
- Experimental Health Psychology, Maastricht University; Research Group Health Psychology, KU Leuven
| | - Ann Meulders
- Experimental Health Psychology, Maastricht University; Research Group Health Psychology, KU Leuven;
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7
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Jafari H, Gholamrezaei A, Franssen M, Van Oudenhove L, Aziz Q, Van den Bergh O, Vlaeyen JWS, Van Diest I. Can Slow Deep Breathing Reduce Pain? An Experimental Study Exploring Mechanisms. J Pain 2020; 21:1018-1030. [PMID: 31978501 DOI: 10.1016/j.jpain.2019.12.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 12/06/2019] [Accepted: 12/19/2019] [Indexed: 12/27/2022]
Abstract
Slow deep breathing (SDB) is commonly employed in the management of pain, but the underlying mechanisms remain equivocal. This study sought to investigate effects of instructed breathing patterns on experimental heat pain and to explore possible mechanisms of action. In a within-subject experimental design, healthy volunteers (n = 48) performed 4 breathing patterns: 1) unpaced breathing, 2) paced breathing (PB) at the participant's spontaneous breathing frequency, 3) SDB at 6 breaths per minute with a high inspiration/expiration ratio (SDB-H), and 4) SDB at 6 breaths per minute with a low inspiration/expiration ratio (SDB-L). During presentation of each breathing pattern, participants received painful heat stimuli of 3 different temperatures and rated each stimulus on pain intensity. Respiration, heart rate, and blood pressure were recorded. Compared to unpaced breathing, participants reported less intense pain during each of the 3 instructed breathing patterns. Among the instructed breathing patterns, pain did not differ between PB and SDB-H, and SDB-L attenuated pain more than the PB and SDB-H patterns. The latter effect was paralleled by greater blood pressure variability and baroreflex effectiveness index during SDB-L. Cardiovascular changes did not mediate the observed effects of breathing patterns on pain. PERSPECTIVES: SDB is more efficacious to attenuate pain when breathing is paced at a slow rhythm with an expiration that is long relative to inspiration, but the underlying mechanisms remain to be elucidated.
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Affiliation(s)
- Hassan Jafari
- KU Leuven - University of Leuven, Research Group Health Psychology, Leuven, Belgium; Biostatistics and Health Informatics Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
| | - Ali Gholamrezaei
- KU Leuven - University of Leuven, Research Group Health Psychology, Leuven, Belgium; KU Leuven - University of Leuven, Department Chronic Diseases, Metabolism & Ageing (CHROMETA), Translational Research Center for Gastrointestinal Disorders (TARGID), Leuven, Belgium
| | - Mathijs Franssen
- KU Leuven - University of Leuven, Research Group Health Psychology, Leuven, Belgium; Center for the Psychology of Learning and Experimental Psychopathology, University of Leuven, Leuven, Belgium
| | - Lukas Van Oudenhove
- KU Leuven - University of Leuven, Department Chronic Diseases, Metabolism & Ageing (CHROMETA), Translational Research Center for Gastrointestinal Disorders (TARGID), Leuven, Belgium
| | - Qasim Aziz
- Wingate Institute of Neurogastroenterology, Centre for Neuroscience and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Omer Van den Bergh
- KU Leuven - University of Leuven, Research Group Health Psychology, Leuven, Belgium
| | - Johan W S Vlaeyen
- KU Leuven - University of Leuven, Research Group Health Psychology, Leuven, Belgium; Experimental Health Psychology, Maastricht University, Maastricht, the Netherlands
| | - Ilse Van Diest
- KU Leuven - University of Leuven, Research Group Health Psychology, Leuven, Belgium
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Franssen M, Langlitz J. Ärztliche Betreuung bei veganer Ernährung. Monatsschr Kinderheilkd 2018. [DOI: 10.1007/s00112-017-0415-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Franssen M, Claes N, Vervliet B, Beckers T, Hermans D, Baeyens F. Reinstatement after human feature-positive discrimination learning. Behav Processes 2017; 137:73-83. [PMID: 28108345 DOI: 10.1016/j.beproc.2017.01.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 01/04/2017] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
In two experiments, using an online conditioned suppression task, we investigated the possibility of reinstatement of extinguished feature-target compound presentations after sequential feature-positive discrimination training in humans. Furthermore, given a hierarchical account of Pavlovian modulation (e.g., Bonardi, 1998; Bonardi and Jennings, 2009), we predicted A-US reinstatement to be stronger than US-only reinstatement. In Experiment 1, participants learned a sequential feature-positive discrimination (X→A+|A-), which was subsequently extinguished (X→A-). During the following reinstatement phase, group US-only received US-only presentations (not signalled), group A-US received A-US presentations, and the Control group received exposure to the context, but no CSs or USs, for an equal amount of time. Reinstatement of differential X→A/A responding was observed in the US-only group but not in the Control or A-US groups. Although differential X→A/A responding was not significant in group A-US, responding to the X→A compound was significantly stronger compared to that in group US-only. Hence, it could be the case the group A-US showed stronger reinstatement, but that differential responding was abolished due to excitation gained by A. Experiment 2 was set up to circumvent the acquired excitation of A by testing transfer of the feature after A-US reinstatement to a different target, B. Participants acquired two discriminations, X→A/A and Y→B/B, of which X→A was then extinguished. Subsequently, group A-US received reinforced presentations of A during a reinstatement phase while group Control received exposure to the context. Final testing of the novel X→B compound was hypothesized to show higher responding in group A-US than in group Control, but findings of this approach were limited due to acquired equivalence and/or perceptual factors causing a secondary extinction effect. We conclude to have obtained clear evidence in favour of reinstatement of differential responding after human Feature-Positive discrimination training and subsequent compound extinction, but no evidence in favour of A-US presentations being a stronger trigger for reinstatement than are US-only presentations.
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Affiliation(s)
- Mathijs Franssen
- Center for the Psychology of Learning and Experimental Psychopathology, University of Leuven, Leuven, Belgium; Health Psychology, University of Leuven, Leuven, Belgium.
| | - Nathalie Claes
- Health Psychology, University of Leuven, Leuven, Belgium; Department of Experimental-Clinical and Health Psychology, University of Ghent, Ghent, Belgium
| | - Bram Vervliet
- Center for the Psychology of Learning and Experimental Psychopathology, University of Leuven, Leuven, Belgium
| | - Tom Beckers
- Center for the Psychology of Learning and Experimental Psychopathology, University of Leuven, Leuven, Belgium
| | - Dirk Hermans
- Center for the Psychology of Learning and Experimental Psychopathology, University of Leuven, Leuven, Belgium
| | - Frank Baeyens
- Center for the Psychology of Learning and Experimental Psychopathology, University of Leuven, Leuven, Belgium
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Garigliany M, Linden A, Gilliau G, Levy E, Sarlet M, Franssen M, Benzarti E, Derouaux A, Francis F, Desmecht D. Usutu virus, Belgium, 2016. Infect Genet Evol 2016; 48:116-119. [PMID: 28017913 DOI: 10.1016/j.meegid.2016.12.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 11/25/2022]
Abstract
During late summer 2016, in a northwest European region extending over Belgium, the Netherlands and the eastern border of the German state of North Rhine Westphalia, an outbreak of wild bird deaths occurred similar to those reported on the continent since 1996. Dead birds were necropsied and examined by complementary methods. Pathologic and immunohistological investigations strongly suggested an infection by Usutu virus. Subsequently, genomic segments of the said virus were detected, the virus was isolated and its complete genome was sequenced. The strain, designated Usutu-LIEGE, is a close phylogenetic relative of those isolated in Germany which form a distinct group within the USUV phylogeny, the so-called Europe_3 lineage. Should this outbreak recapitulate the characteristics of those in southwest Germany in 2011 and in/around Vienna (Austria) in 2001, it is expected that specific avian populations in the affected area will face a significant reduction in size for a few years.
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Affiliation(s)
- M Garigliany
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium
| | - A Linden
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium; Surveillance Network for Wildlife Diseases, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium
| | - G Gilliau
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium
| | - E Levy
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium
| | - M Sarlet
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium
| | - M Franssen
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium
| | - E Benzarti
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium
| | - A Derouaux
- Natagora, c/o Maison Liégeoise de l'Environnement, Rue Fusch 3, B-4000 Liège, Belgium
| | - F Francis
- Functional and Evolutive Entomology, Gembloux Agro-Bio Tech., University of Liège, Passage des Déportés 2, B-5030 Gembloux, Belgium
| | - D Desmecht
- FARAH Research Center, Faculty of Veterinary Medicine, University of Liège, Sart Tilman B43, B-4000 Liège, Belgium.
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Jennings DJ, Alonso E, Mondragón E, Franssen M, Bonardi C. The effect of stimulus distribution form on the acquisition and rate of conditioned responding: implications for theory. ACTA ACUST UNITED AC 2013; 39:233-48. [PMID: 23627799 DOI: 10.1037/a0032151] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In four experiments rats were conditioned to an auditory conditioned stimulus (conditioned stimulus; CS) that was paired with food, and learning about the CS was compared across two conditions in which the mean duration of the CS was equated. In one, the CS was of a single, fixed duration on every trial, and in the other the CS duration was drawn from an exponential distribution, and hence changed from trial to trial. Higher rates of conditioned responding to the fixed than to the variable stimulus were observed, in both between- (Experiment 1) and within-subject designs (Experiments 2 and 3). Moreover, this difference was maintained when stimuli trained with fixed or variable durations were tested under identical conditions (i.e., with equal numbers of fixed and variable duration trials)-suggesting that the difference could not be attributed to performance effects (Experiment 3). In order to estimate the speed of acquisition of conditioned responding, the scaled cumulative distribution of a Weibull function was fitted to the trial-by-trial response rates for each rat. In the within-subject experiments specific differences in the pattern of acquisition to fixed and variable CS were shown; a somewhat different pattern was found when intertrial interval (ITI) was manipulated (Experiment 4). The implications of these findings for theories of conditioning and timing are discussed.
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Affiliation(s)
- Dómhnall J Jennings
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.
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Paul A, John H, Oakley L, Deeley D, Samaranayaka M, Klocke R, Murley A, Webb E, Al-Allaf A, Panchal S, Moorthy A, Samanta A, Rajak R, Zaman M, Camilleri J, Nash J, Negi A, Jones S, Hull DN, Smith AS, Taylor PC, Hughes L, Done J, Young A, Colijn E, Franssen M, Rabsztyn PRI, van den Ende CHM, Williams A, Graham A, Davies S, Longrigg K, Dagg A, Lyons C, Bowen C, Wright S, Cornell P, Richards S. BHPR - audit/service delivery: 93. Taking Care of the Foot Health of Rheumatology Patients: Where Do We Stand Now? Rheumatology (Oxford) 2011. [DOI: 10.1093/rheumatology/ker044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Nowacki M, Viemann D, Stege D, Franssen M, Hörnig-Franz I, Burns JC, Kehl HG. Therapierefraktäres Kawasaki Syndrom bei einem 7 Wochen alten Säugling- Erfolgreiche Behandlung mit anti-TNF-α und Cyclosporin A. Klin Padiatr 2010. [DOI: 10.1055/s-0030-1261634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Musters A, Franssen M, van der Veen F, Repping S, Goddijn M, Korevaar J. Pregnancy outcome after PGD in couples with recurrent miscarriage and carrying a structural chromosome abnormality: a systematic review. Fertil Steril 2009. [DOI: 10.1016/j.fertnstert.2009.07.1025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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van de Kerkhof PC, Franssen M, de La Brassine M, Kuipers M. Calcipotriol cream in the morning and ointment in the evening: a novel regimen to improve compliance. J DERMATOL TREAT 2009; 12:75-9. [PMID: 12243662 DOI: 10.1080/095466301317085345] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Calcipotriol ointment and calcipotriol cream have both been shown to be effective in the treatment of psoriasis. AIM To find out the patient compliance, efficacy and tolerance to a regimen of a calcipotriol cream application in the morning and a calcipotriol ointment application in the evening. METHODS In order to obtain data relevant to daily practice, information was obtained from patients and dermatologists on the treatment of psoriasis with a combination of calcipotriol ointment and calcipotriol cream. In total, three assessments were carried out: at the beginning, after 3 weeks and after 8 weeks. The first assessment comprised general demographics, localization of the lesions, the percentage body surface involved, and details on other antipsoriatic medications. The second and third assessments were an evaluation of compliance and efficacy in comparison with calcipotriol ointment monotherapy, provided that the patients had experience with this treatment. In total, 976 patients were included by 170 dermatologists in The Netherlands and Belgium. RESULTS Compliance with the combined use of calcipotriol cream in the morning and calcipotriol ointment in the evening was optimal in 60-70% of the patients. The highest compliance was shown at the second visit but dropped at the third visit. Those patients with previous experience of calcipotriol ointment indicated that the calcipotriol cream/ointment regimen was a better principle. Response to the calcipotriol cream/ointment regimen was considered good in 67-76% of the patients. CONCLUSION The present study indicates that the combined use of calcipotriol cream in the morning and ointment in the evening is useful as a principle for mild to severe psoriasis. A total of 67-68% of the patients stated that this regimen was the most preferred topical treatment of psoriasis.
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Affiliation(s)
- P C van de Kerkhof
- Department of Dermatology, University Hospital Nijmegen, The Netherlands
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van Lankveld W, Franssen M, Stenger A. Gerontorheumatology: the challenge to meet health-care demands for the elderly with musculoskeletal conditions. Rheumatology (Oxford) 2005; 44:419-22. [PMID: 15695295 DOI: 10.1093/rheumatology/keh555] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Jasmin L, Kohan L, Franssen M, Janni G, Goff JR. The cold plate as a test of nociceptive behaviors: description and application to the study of chronic neuropathic and inflammatory pain models. Pain 1998; 75:367-82. [PMID: 9583773 DOI: 10.1016/s0304-3959(98)00017-7] [Citation(s) in RCA: 153] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A cold plate apparatus was designed to test the responses of unrestrained rats to low temperature stimulation of the plantar aspect of the paw. At plate temperatures of 10 degrees C and 5 degrees C, rats with either chronic constriction injury (CCI) of the sciatic nerve or complete Freund's adjuvant (CFA) induced inflammation of the hindpaw displayed a stereotyped behavior. Brisk lifts of the treated hindpaw were recorded, while no evidence of other nociceptive behaviors could be discerned. The most consistent responses were obtained with a plate temperature of 5 degrees C in three 5-min testing periods, separated by 10-min intervals during which the animals were returned to a normal environment. Concomitantly to cold testing, the rats were evaluated for their response to heat (plantar test) and mechanical (von Frey hairs) stimuli. In both injury models, while responses to heat stimuli had normalized at 60 days post-injury, a clear lateralization of responses to cold was observed throughout the entire study period. Systemic lidocaine, clonidine, and morphine suppressed responses to cold in a dose-related fashion. At doses that did not affect motor or sensory behavior, both lidocaine and its quaternary derivative QX-314 similarly reduced paw lifts, suggesting that cold hyperalgesia is in part due to peripheral altered nociceptive processing. Clonidine was more potent in CCI then in CFA rats in reducing the response to cold. Paradoxically, clonidine increased the withdrawal latencies to heat in the CCI hindpaw at 40 days and thereafter, at a time when both hindpaws had the same withdrawal latencies in control animals. Morphine was also more potent on CCI than CFA cold responses, indicating that, chronically, CFA-induced hyperalgesia might be opiate resistant. Evidence for tonic endogenous inhibition of cold hyperalgesia was obtained for CFA rats, when systemic naltrexone significantly increased the number of paw lifts; this was not found in rats with CCI. At 60 days, neither morphine nor naltrexone affected cold-induced paw lifting in CFA rats, suggesting that the neuronal circuit mediating cold hyperalgesia in these animals had become opiate insensitive. In conclusion, the cold plate was found to be a reliable method for detecting abnormal nociceptive behavior even at long intervals after nerve or inflammatory injuries, when responses to other nociceptive stimuli have returned to near normal. The results of pharmacological studies suggest that cold hyperalgesia is in part a consequence of altered sensory processing in the periphery, and that it can be independently modulated by opiate and adrenergic systems.
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Affiliation(s)
- L Jasmin
- Department of Neurosurgery, Georgetown University Medical Center, Washington, DC 20007, USA.
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van Lankveld W, van't Pad Bosch P, Bakker J, Terwindt S, Franssen M, van Riel P. Sequential occupational dexterity assessment (SODA): a new test to measure hand disability. J Hand Ther 1996; 9:27-32. [PMID: 8664936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Measuring hand-related disability poses a problem due to a lack of validated tests. This report introduces the sequential occupational dexterity assessment (SODA), a test that measures bimanual dexterity in daily life. The design of the SODA is described. Validity and reliability of the SODA are demonstrated in a sample of patients with rheumatoid arthritis (RA), in whom impairment of the hands may cause serious disability in daily life. Good reliability was found, as measured by internal consistency, test-retest correlation, and interrater stability. Validity was established by relating the SODA to a number of other variables. Current disease activity was only weakly related to the SODA score. Impairment of the hands is more strongly related to dexterity than to current disease activity. However, dexterity could vary considerably in patients with similar degrees of impairment. Pain during the SODA proved to be more important for dexterity than general level of pain. Considerable variation was found in self-reported and observed dexterity. It was concluded that the SODA may guide the therapist in making decisions about hand therapy. The use of the SODA allows standardized evaluation of the effects of hand surgery on bimanual dexterity.
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Affiliation(s)
- W van Lankveld
- Department of Research and Development (ARO), St. Maartenskliniek, Nijmegen, The Netherlands
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Franssen M, Moutschen J. Mutagenicity of N-methylnitrosourea (NMU) and N-ethyl nitrosourea (NEU) in the moss Pogonatum aloides (Hedw.) P. Beauv. Mutat Res 1972; 16:141-50. [PMID: 5074516 DOI: 10.1016/0027-5107(72)90174-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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