References of "SALMON, Eric"
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See detailEffects of aging on task- and stimulus-related cerebral attention networks
Kurth, Sophie ULg; Majerus, Steve ULg; Bastin, Christine ULg et al

in Neurobiology of Aging (2016), 44

Interactions between a dorsal attention (DAN) and a ventral attention cerebral network (VAN) have been reported in young participants during attention or short term memory (STM) tasks. Since it remains an ... [more ▼]

Interactions between a dorsal attention (DAN) and a ventral attention cerebral network (VAN) have been reported in young participants during attention or short term memory (STM) tasks. Since it remains an under-investigated question, age effects on DAN and VAN activity and their functional balance were explored during performance of a STM task. Older and young groups showed similar behavioral patterns of results. At the cerebral level, DAN activation increased as a function of increasing STM load in both groups, suggesting preserved activity in DAN during healthy aging. Age-related over-recruitment in regions of the DAN in the higher task load raised the question of compensation attempt versus less efficient use of neural resources in older adults. Lesser decrease of VAN activation with increasing load and decreased stimulus-driven activation in the VAN, especially in the higher load, in older participants suggested age-related reduced response in the VAN. However, functional connectivity measures showed that VAN was still functionally connected to the DAN in older participants. [less ▲]

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See detailDisrupted interaction between self and memory in patients with Alzheimer’s disease
Genon, Sarah ULg; Salmon, Eric ULg; Collette, Fabienne ULg et al

Conference (2016, July)

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship ... [more ▼]

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship can be disrupted. This was evidenced by impaired SRE and SRRE in AD for recognition of adjectives previously judged for self-relevance, as well as recall of names of people previously linked to the self. For both materials, a qualitative impairment of the recollective experience for the self-related items was also observed in AD. A neuroimaging approach suggested that reduced SRE is related to decreased grey matter volume in the lateral prefrontal cortex (lPFC). Thus, retrieval of recent self-related memories is impaired in relation to altered high-order processes in lPFC in AD. [less ▲]

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See detailRecollection versus familiarity in normal aging and in mild cognitive impairment: Impact of test format
Gilsoul, Jessica ULg; Simon, Jessica ULg; SALMON, Eric ULg et al

Poster (2016, March 18)

Objectives. Memory retrieval typically involves a combination of recollection and familiarity. However, test format can promote one or the other process (Norman & O’Reilly, 2003). The aim of this study ... [more ▼]

Objectives. Memory retrieval typically involves a combination of recollection and familiarity. However, test format can promote one or the other process (Norman & O’Reilly, 2003). The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in mild cognitive impairment (MCI). Methods. Seventy young participants (18-30 years), 65 “younger-old” (55- 69 years), 53 “older-old” (70-85 years), and 13 MCIs (55-82 years) were enrolled. In the “forced-choice” task, they had to recognize which picture, among three, was presented during the encoding stage. In the “yes/no” task, they had to judge whether each item, successively presented, was previously seen or not. In each task, they had to give a “Remember/Know/Guess” judgment. Results. Group × Format repeated measures ANOVAs revealed that young people had better recognition performance (d’) than “younger-old”, which were better than “older-old” and MCIs. Moreover, young people used familiarity more accurately than both groups of old participants and MCIs, with MCIs being equivalent to “younger-old” and “older-old”. However, MCIs displayed a high rate of familiarity-based false alarms. The resort to recollection decreased with age and in MCIs. Finally, Group × Format interaction revealed that young people (but not the other groups) could use recollection more often in the “forcedchoice” task compared to the “yes/no” task. Conclusions. Recollection and familiarity decline progressively in healthy aging. In MCI, recollection is more affected than familiarity, but patients demonstrated a more liberal use of familiarity. Finally, test format did not influence strongly the results. [less ▲]

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See detailCorrelation between resting state fMRI total neuronal activity and PET metabolism in healthy controls and patients with disorders of consciousness
Soddu, Andrea ULg; Gomez, Francisco; Heine, Lizette ULg et al

in Brain and Behavior (2016)

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made ... [more ▼]

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made it possible to assess changes in metabolic activity in clinical applications, such as the study of severe brain injury and disorders of consciousness. Objective: We assessed the possi- bility of creating functional MRI activity maps, which could estimate the rela- tive levels of activity in FDG-PET cerebral metabolic maps. If no metabolic absolute measures can be extracted, our approach may still be of clinical use in centers without access to FDG-PET. It also overcomes the problem of recogniz- ing individual networks of independent component selection in functional mag- netic resonance imaging (fMRI) resting state analysis. Methods: We extracted resting state fMRI functional connectivity maps using independent component analysis and combined only components of neuronal origin. To assess neu- ronality of components a classification based on support vector machine (SVM) was used. We compared the generated maps with the FDG-PET maps in 16 healthy controls, 11 vegetative state/unresponsive wakefulness syndrome patients and four locked-in patients. Results: The results show a significant similarity with q = 0.75  0.05 for healthy controls and q = 0.58  0.09 for vegetative state/unresponsive wakefulness syndrome patients between the FDG- PET and the fMRI based maps. FDG-PET, fMRI neuronal maps, and the conjunction analysis show decreases in frontoparietal and medial regions in vegetative patients with respect to controls. Subsequent analysis in locked-in syndrome patients produced also consistent maps with healthy controls. Conclusions: The constructed resting state fMRI functional connectivity map points toward the possibility for fMRI resting state to estimate relative levels of activity in a metabolic map. [less ▲]

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See detailImpact du format du test sur la recollection et la familiarité dans le vieillissement normal et le trouble cognitif léger de type amnésique
Simon, Jessica ULg; Gilsoul, Jessica ULg; SALMON, Eric ULg et al

Conference (2015, December 04)

Les tâches de reconnaissance à choix-forcé et oui/non ont largement été utilisées dans l’évaluation de la mémoire. Selon Norman et O’Reilly (2003), le format oui/non ferait davantage intervenir la ... [more ▼]

Les tâches de reconnaissance à choix-forcé et oui/non ont largement été utilisées dans l’évaluation de la mémoire. Selon Norman et O’Reilly (2003), le format oui/non ferait davantage intervenir la recollection alors que le format à choix-forcé favoriserait la comparaison du sentiment de familiarité associé à chaque item et la sélection du plus familier. L’objectif de cette étude est d’explorer l’impact du format du test sur la recollection et la familiarité au travers du vieillissement normal et pathologique. Septante participants jeunes (18 - 30 ans), 65 participants jeunes-âgés (55 - 69 ans), 53 participants âgés-âgés (70-85 ans) et 13 patients présentant un trouble cognitif léger amnésique (55-82 ans) ont réalisé deux tâches de reconnaissance. Pour chaque tâche, lors de l’encodage, nous avons présenté, à deux reprises, 25 images à mémoriser. Dans la tâche de reconnaissance à choix forcé, les participants devaient reconnaitre parmi trois images très semblables celle qui a été vue précédemment. Dans la tâche de reconnaissance oui/non, les items étaient présentés successivement et les participants devaient reconnaitre ceux présentés à l’encodage. Pour chaque item reconnu, les participants devaient fournir un jugement Remember/Know/Guess. Les ANOVA Groupe x Format à mesures répétées sur la dernière variable (p<0,05) ont révélé que les jeunes avaient de meilleures performances en reconnaissance (score d’) que les jeunes-âgés, qui ont eux-mêmes de meilleures performances que les âgés-âgés et les patients. En outre, les jeunes utilisent plus souvent le sentiment de familiarité pour reconnaître les images étudiées que les participants âgés et les patients. De plus, les participants jeunes-âgés utilisent plus souvent la familiarité que les participants âgés-âgés, alors qu’il n’y a pas de différence entre ceux-ci et les patients. Cependant, les fausses alarmes associées à la familiarité augmentent progressivement dans le vieillissement et la pathologie. L’utilisation de la recollection est progressivement réduite avec l’âge et altérée dans la pathologie. Enfin, les jeunes tendent à utiliser plus souvent la recollection dans la tâche à choix-forcé (p=0,055), alors qu’il n’y a pas de différence pour les autres groupes. Tous ces résultats suggèrent que le vieillissement normal s’accompagne d’un déclin progressif de la recollection et de la familiarité. Dans le vieillissement pathologique, on observe des performances similaires au groupe le plus âgé en reconnaissance malgré un déficit de recollection. Les patients utilisent la familiarité autant que les deux groupes âgés bien que les taux de fausses alarmes soient plus importants, suggérant une utilisation privilégiée mais inadéquate de ce processus. [less ▲]

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See detailThe impact of ageing on episodic memory encoding: an fMRI study
François, Sarah ULg; Angel, Lucie; SALMON, Eric ULg et al

Poster (2015, September 04)

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See detailEVALUATION OF SV2Alox/Cre TRANSGENIC MOUSE USING [18F]UCB-H IN IN VITRO AUTORADIOGRAPHY
Serrano Navacerrada, Maria Elisa ULg; Becker, Guillaume ULg; MENTEN, Catherine ULg et al

Poster (2015, September 04)

Background: SV2A is the most studied isoform of the Synaptic Vesicle 2 proteins, which are involved in the synaptic vesicle trafficking. Interestingly, the SV2A has been identify as the binding site for ... [more ▼]

Background: SV2A is the most studied isoform of the Synaptic Vesicle 2 proteins, which are involved in the synaptic vesicle trafficking. Interestingly, the SV2A has been identify as the binding site for the antiepileptic drug levetiracetam, showing a close relation between the epilepsy, the dysregulation of the SV2A levels and the response to antiepileptic medications. SV2A floxed-mice were developed using a cre-lox technique, leading to a strong decrease of SV2A expression in the CA3 field of the hippocampus. We aim here to validate this model using [18F]UCB-H, a novel PET imaging radiotracer with a nanomolar affinity for human SV2A. Methods: In vitro autoradiography were performed on SV2Alox/Cre+ transgenic mouse brain slices. SV2Alox/Cre- mouse was used as control. To obtain a structural reference, brain slices underwent eosin-haematoxylin staining. Images of both procedures were coregistered using π-PMOD software. Regions of interest (Dentate Gyrus, CA1, CA2 and CA3) were drawn according to a stereotaxic atlas of the mouse brain. Results: Analyses showed significant differences in radiotracer binding (p<0.001) between SV2Alox/Cre+ mouse and SV2Alox/Cre- mouse highlighting an important reduction for the labelling density in Ammon's horn, particularly in CA1, compared to Dentate Gyrus where the diminution was less marked. Conclusions: Here, we used the radiotracer [18F]UCB-H to probe the decreased expression of SV2A protein in the hippocampus of SV2Alox/Cre+ mouse versus SV2Alox/Cre- control mouse. Our results contribute to the validation of the model, and encourage us to proceed with further longitudinal and behavioural studies. [less ▲]

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See detailThe impact of ageing on episodic memory encoding: an fMRI study
François, Sarah ULg; Angel, Lucie; Salmon, Eric ULg et al

Poster (2015, May 28)

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear ... [more ▼]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear to recruit prefrontal areas bilaterally when their encoding is successful, while in young adults this activation is found to be left-lateralized (b). In this study, we were interested in the differences between younger and older participant regarding cerebral activity during encoding depending on whether the item elicited recollection or familiarity during the recognition phase. Twenty young volunteers (aged 19 to 29 years old) and 19 older volunteers (aged 60 to 78 years old) were presented visual stimuli depicting objects. During a first fMRI session, they were asked to make a size judgement about them. Then, in a second phase, the subjects were shown the items previously encountered during the encoding phase, as well as distractors. Participants' task was to determine which one were new and which one were seen earlier. For the latter, they also performed a Remember-Know judgement. Data were analysed using SPM8, with an event design comparing modifications in cerebral activity between the two subjects groups during encoding (1) for the items leading to recollection during the recognition phase compared to those leading to familiarity, and (2) for the items associated with familiarity during the recognition phase compared to those which were not recognized. Results show that older adults display a heightened activity in the right middle frontal gyrus, medial cingulate and paracingulate left gyri as well as in the precuneus, bilaterally when they engage recollection processes. Given that activations in these areas did not correlate with performance, they could be interepreted either as dedifferentiation or as an attempt of the ageing brain to compensate for a less elaborate encoding. However, no increase of activity was associated with familiarity processes in older adults, possibly because they are less demanding regarding attentional resources. (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Duverne, S., Motamedinia, S., & Rugg, M. D. (2009). The relationship between aging, performance, and the neural correlates of successful memory encoding. Cerebral Cortex, 19(3), 733-744. doi:10.1093/cercor/bhn122 [less ▲]

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See detailThe neural bases of proactive and reactive control processes in healthy aging
Manard, Marine ULg; François, Sarah ULg; SALMON, Eric ULg et al

Poster (2015, May 28)

Background. Research on cognitive control suggests an age-related decline in proactive control abilities (an anticipatory form of control) whereas reactive control (consecutive to conflict detection ... [more ▼]

Background. Research on cognitive control suggests an age-related decline in proactive control abilities (an anticipatory form of control) whereas reactive control (consecutive to conflict detection) seems to remain intact [1]. As proactive and reactive control abilities were associated to specific brain networks [2], this study investigated age-related effects on the neural substrates associated to each kind of control. Method. A modified form of the Stroop task was administered to 16 young and 16 older adults in an event-related fMRI experiment. In this version of the Stroop task, three different contexts were created: (1) a mostly congruent context (MC, inducing reactive control) with a majority of congruent items, (2) a mostly incongruent context (MI, inducing proactive control) with mainly interfering items, (3) a neutral context (MN) with mainly neutral items. Preprocessing and statistical analyses were performed with SPM8 (p<.001 uncorrected). Results. Behavioral results (p<0.05) indicated faster processing of interferent items in the MI than MC context in young participants only. With regard to neuroimaging data, the comparison of the two groups showed that the processing of interferent items in the MI context is associated to decreased activity in (mainly right-sided) frontal and temporal areas in the older group. On the contrary, in the MC context, increased activity was observed in bilateral frontal areas for older compared to younger participants. Discussion. Behavioral results confirm that older participants have difficulties with the implementation of proactive control that is associated to decreased brain activity (compared to young participants) in areas underlying Stroop performance. However, the recruitment of supplementary frontal areas we observed in the reactive control condition suggests compensation processes. So, aging seems to differentially affect the neural networks associated to the various kinds of cognitive control. [less ▲]

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See detailThe impact of ageing on episodic memory encoding: an fMRI study
François, Sarah ULg; Angel, Lucie; Salmon, Eric ULg et al

Poster (2015, May 21)

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear ... [more ▼]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear to recruit prefrontal areas bilaterally when their encoding is successful, while in young adults this activation is found to be left-lateralized (b). In this study, we were interested in the differences between younger and older participant regarding cerebral activity during encoding depending on whether the item elicited recollection or familiarity during the recognition phase. Twenty young volunteers (aged 19 to 29 years old) and 19 older volunteers (aged 60 to 78 years old) were presented visual stimuli depicting objects. During a first fMRI session, they were asked to make a size judgement about them. Then, in a second phase, the subjects were shown the items previously encountered during the encoding phase, as well as distractors. Participants' task was to determine which one were new and which one were seen earlier. For the latter, they also performed a Remember-Know judgement. Data were analysed using SPM8, with an event design comparing modifications in cerebral activity between the two subjects groups during encoding (1) for the items leading to recollection during the recognition phase compared to those leading to familiarity, and (2) for the items associated with familiarity during the recognition phase compared to those which were not recognized. Results show that older adults display a heightened activity in the right middle frontal gyrus, medial cingulate and paracingulate left gyri as well as in the precuneus, bilaterally when they engage recollection processes. Amongst those regions, the precuneus seems to underlie compensatory processes, allowing the elderly to perform a richer encoding, as it was previously suggested for recollection processes during recall (c). However, no increase in activity was associated with familiarity processes in older adults, possibly because they are less demanding regarding attentional resources. (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Duverne, S., Motamedinia, S., & Rugg, M. D. (2009). The relationship between aging, performance, and the neural correlates of successful memory encoding. Cerebral Cortex, 19(3), 733-744. doi:10.1093/cercor/bhn122 (c) Angel, L., Bastin, C., Genon, S., Balteau, E., Phillips, C., Luxen, A., . . . Collette, F. (2013). Differential effects of aging on the neural correlates of recollection and familiarity. Cortex, 49(6), 1585-1597. doi:10.1016/j.cortex.2012.10.002 [less ▲]

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See detail[18F]UCB-H as a new PET radiotracer for Synaptic vesicle protein 2A: A first clinical trial.
Bahri, Mohamed Ali ULg; Stifkens, M; Bastin, Christine ULg et al

in Tijdschrift voor Nucleaire Geneeskunde (2015, May 09), 37(3), 1457-1458

The synaptic vesicle protein 2A (SV2A) is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is ... [more ▼]

The synaptic vesicle protein 2A (SV2A) is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is shown, e.g., by the fact that it is a binding site and the primary mechanism of the antiepileptic drug levetiracetam. This drug has recently been suggested to reduce synaptic deficits in a mouse model for Alzheimer’s disease. We here aimed to investigate the cerebral distribution of [18F]UCB-H, which has a high affinity with the SV2A. Dynamic PET data of the head of 4 healthy volunteers were acquired over 100 minutes after injection of 170.4 ± 24.9 MBq of GMP produced [18F]UCB-H. The arterial input function (IF) was obtained by blood sampling but also derived from the dynamic data using the correlation coefficient method. Blood data revealed a consistent amount of [18F]UCB-H in whole blood and plasma indicating a very low degree of binding of the tracer to the red blood cells. The unchanged fraction of [18F]UCB-H in plasma showed a bi-exponential behavioral decrease with a starting fraction of 92% of the injected amount of the tracer, measured at 3 min post injection. This fraction decreased to about 50% at 10 min post injection. The image-derived arterial IFs showed to be very similar to the measured ones with a peak-ratio around 0.91 and an area-under-curve ratio about 0.98. The PET images showed a high and rapid uptake of [18F]UCB-H in the grey matter structures, matching the known ubiquitous distribution of the SV2A in the brain. The kinetics of the tracer in the brain was characterized by an initial high uptake phase followed by rapid washout. For the three standard compartmental models (1-tissue, 2-tissue, and Logan Plot), similar results were obtained with both the measured and image-derived IFs. Nevertheless the two-tissue compartment model fitted the experimental data best and provided a total distribution volume of the [18F]UCB-H in the brain greater than 7 mL/cm3 and a specific distribution volume around 3 mL/cm3. Our results suggest that [18F]UCB-H is a good candidate as radiotracer for brain SV2A proteins and could be used for human studies (dosimetry has already been reported elsewhere). Image-derived IF showed to be useful for quantitative studies without the need to the arterial blood sampling. This new tracer could help to assess SV2A modifications in neurological pathologies such as Alzheimer’s disease. [less ▲]

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See detailRetirement age and the age of onset of Alzheimer’s disease: Results from the ICTUS study
Grotz, Catherine ULg; Letenneur, Luc; Bonsang, Eric ULg et al

in PLoS ONE (2015), 10(2), 0115056

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See detail[18F]UCB-H as a new PET radiotracer for Synaptic vesicle protein 2A: A first clinical trial
Bahri, Mohamed Ali ULg; Stifkens, Mathieu; Bastin, Christine ULg et al

Poster (2015, January 27)

SV2A is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is shown, e.g., by the fact that it is ... [more ▼]

SV2A is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is shown, e.g., by the fact that it is a binding site and the primary mechanism of levetiracetam. Levetiracetam is an antiepileptic drug which has recently been suggested to reduce synaptic deficits in a mouse model for Alzheimer’s disease. We here aimed to investigate the cerebral distribution of [18F]UCB-H, which has a high affinity with the SV2A. Dynamic PET data of the head of 4 healthy volunteers were acquired over 100 minutes after injection of 170.4 ± 24.9 MBq of GMP produced [18F]UCB-H. The arterial input function (IF) was obtained by blood sampling. The IF was also derived from the dynamic data using the correlation coefficient method. Blood data revealed a consistent amount of [18F]UCB-H in whole blood and plasma indicating a very low degree of binding of the tracer to the red blood cells. The image-derived arterial IFs were showed to be very similar to the measured ones with a peak-ratio around 0.91 and an area-under-curve ratio about 0.98. The [18F]UCB-H PET data showed a high and rapid uptake in the grey matter structures, matching the known ubiquitous distribution of the SV2A in the brain. The kinetics of the tracer in the brain was characterized by an initial high uptake phase followed by rapid washout allowing the standard compartmental modeling (1-tissue, 2-tissue, and Logan Plot). The three models gave similar results with both the measured and image-derived IFs. The total distribution volume of the tracer in the brain was greater than 7 mL/cm3. Our results suggest that [18F]UCB-H is a good candidate as radiotracer for brain SV2A proteins and could be used for human studies. Image-derived IF showed to be useful for quantitative studies without the need to the arterial blood sampling. SV2A modifications may consequently be assessed in neurological pathologies such as Alzheimer’s disease. [less ▲]

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See detailBiodistribution and radiation dosimetry for the novel SV2A radiotracer [18F]UCB-H: First-in-human study.
Bretin, Florian ULg; Bahri, Mohamed Ali ULg; BERNARD, Claire ULg et al

in Molecular Imaging & Biology (2015), 17

Abstract- [18F]UCB-H is a novel radiotracer with a high affinity for SV2A, a protein expressed in synaptic vesicles. SV2A is the binding site of levetiracetam, a “first in class” antiepileptic drug with a ... [more ▼]

Abstract- [18F]UCB-H is a novel radiotracer with a high affinity for SV2A, a protein expressed in synaptic vesicles. SV2A is the binding site of levetiracetam, a “first in class” antiepileptic drug with a distinct but still poorly understood mechanism of action. The objective of this study was to determine the biodistribution and radiation dosimetry of [18F]UCB-H in a human clinical trial and to establish injection limits according to biomedical research guidelines. Additionally, the clinical radiation dosimetry results were compared to estimations in previously published preclinical data. Dynamic whole body PET/CT imaging was performed over approximately 110 minutes on five healthy male volunteers after injection of 144.5 ± 7.1 MBq (range, 139.1 – 156.5 MBq) of [18F]UCB-H. Major organs were delineated on CT images and time-activity curves were obtained from co-registered dynamic PET emission scans. Time-integrated activity coefficients were calculated as area under the curve using trapezoidal numerical integration. Urinary excretion data based on PET-activities including voiding was simulated using the dynamic bladder module of OLINDA/EXM. The radiation dosimetry was calculated using OLINDA/EXM. The effective dose to the OLINDA/EXM 70 kg standard male was 1.54E-02 ± 6.84E-04 mSv/MBq, with urinary bladder wall, gallbladder wall and the liver receiving the highest absorbed dose. The brain, the tracer’s main organ of interest, received an absorbed dose of 1.89E-02 ± 2.32E-03 mGy/MBq. This first human dosimetry study of [18F]UCB-H indicated that the tracer shows similar radiation burdens to widely used common clinical tracers. Single injections of at maximum 672 MBq for USA practice and 649 MBq for European practice keep radiation exposure below recommended limits. Recently published preclinical dosimetry data extrapolated from mice provided satisfactory prediction of total body and effective dose, but showed significant differences in organ absorbed doses compared to human data. [less ▲]

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