2024
Head-to-head comparison of [18F]-Flortaucipir, [18F]-MK-6240 and [18F]-PI-2620 postmortem binding across the spectrum of neurodegenerative diseases
Aguero C, Dhaynaut M, Amaral A, Moon S, Neelamegam R, Scapellato M, Carazo-Casas C, Kumar S, El Fakhri G, Johnson K, Frosch M, Normandin M, Gómez-Isla T. Head-to-head comparison of [18F]-Flortaucipir, [18F]-MK-6240 and [18F]-PI-2620 postmortem binding across the spectrum of neurodegenerative diseases. Acta Neuropathologica 2024, 147: 25. PMID: 38280071, PMCID: PMC10822013, DOI: 10.1007/s00401-023-02672-z.Peer-Reviewed Original ResearchConceptsNon-AD tauopathiesTau aggregationTau PET tracersDNA-binding proteinsBinds to neurofibrillary tanglesSecond-generation tau tracersTransactive response DNA-binding proteinSpectrum of neurodegenerative diseasesNeurofibrillary tanglesTau lesionsMelanin-containing cellsTDP-43Binding signalTauopathiesBinding targetsCerebral amyloid angiopathyOff-target bindingB-amyloidBinding patternsNeurodegenerative diseasesTau tracersTauBinding to areasBinding profilesBinding
2023
Tau Positron Emission Tomography and Neurocognitive Function Among Former Professional American-Style Football Players
Dhaynaut M, Grashow R, Normandin M, Wu O, Marengi D, Terry D, Sanchez J, Weisskopf M, Speizer F, Taylor H, Guehl N, Seshadri S, Beiser A, Daneshvar D, Johnson K, Iverson G, Zafonte R, Fakhri G, Baggish A. Tau Positron Emission Tomography and Neurocognitive Function Among Former Professional American-Style Football Players. Journal Of Neurotrauma 2023, 40: 1614-1624. PMID: 37282582, PMCID: PMC10458363, DOI: 10.1089/neu.2022.0454.Peer-Reviewed Original ResearchConceptsPositron emission tomographyDistribution volume ratioNeuropsychological testsNeurocognitive functionStandardized uptake value ratioControl participantsMeasures of neurocognitive functionStructural magnetic resonance imagingMeasures of memoryDepressive symptom severityMale control participantsEmission tomographyCerebellar gray matterNeuropsychological measuresTau positron emission tomographyExecutive functionSymptom severityBrain regionsEntorhinal cortexRepetitive head impactsP-tauReference regionFormer playersRepetitive head impact exposureMale controlsMeasurement of Cerebral Perfusion Indices from the Early Phase of [18F]MK6240 Dynamic Tau PET Imaging
Guehl N, Dhaynaut M, Hanseeuw B, Moon S, Lois C, Thibault E, Fu J, Price J, Johnson K, El Fakhri G, Normandin M. Measurement of Cerebral Perfusion Indices from the Early Phase of [18F]MK6240 Dynamic Tau PET Imaging. Journal Of Nuclear Medicine 2023, 64: 968-975. PMID: 36997330, PMCID: PMC10241011, DOI: 10.2967/jnumed.122.265072.Peer-Reviewed Original ResearchConceptsTime-activity curvesCerebral perfusionMetabolite-corrected arterial input functionBrain time-activity curvesEarly phaseRegional time-activity curvesIndices of cerebral perfusionDynamic [<sup>18</sup>FBlood-brain barrierPlasma to brain tissueStatistically significant differenceArterial blood samplesForty-nine subjectsCNArterial input functionPathophysiological mechanismsPerfusion indicatorsPET imagingBlood samplesSignificant differenceSurrogate indexNoninvasive estimationAnatomical informationCompound BForty-nine
2022
Impact of 40 Hz Transcranial Alternating Current Stimulation on Cerebral Tau Burden in Patients with Alzheimer’s Disease: A Case Series1
Dhaynaut M, Sprugnoli G, Cappon D, Macone J, Sanchez J, Normandin M, Guehl N, Koch G, Paciorek R, Connor A, Press D, Johnson K, Pascual-Leone A, Fakhri G, Santarnecchi E. Impact of 40 Hz Transcranial Alternating Current Stimulation on Cerebral Tau Burden in Patients with Alzheimer’s Disease: A Case Series1. Journal Of Alzheimer's Disease 2022, 85: 1667-1676. PMID: 34958021, PMCID: PMC9023125, DOI: 10.3233/jad-215072.Peer-Reviewed Original ResearchConceptsMicroglia activationGamma spectral powerDecrease of microglia activationNo adverse eventsTranscranial alternating current stimulationSlow disease progressionPlacebo-controlled conditionsPreclinical dataCase seriesAdverse eventsGamma oscillationsElectrophysiological assessmentP-tauMouse modelDisease progressionMesial regionMild to moderate ADAnimal modelsPatientsPET imagingAlzheimer's diseaseSpectral powerAD mouse modelAD patientsProtein clearance
2019
[18F]-AV-1451 binding profile in chronic traumatic encephalopathy: a postmortem case series
Marquié M, Agüero C, Amaral A, Villarejo-Galende A, Ramanan P, Chong M, Sáez-Calveras N, Bennett R, Verwer E, Kim S, Dhaynaut M, Alvarez V, Johnson K, McKee A, Frosch M, Gómez-Isla T. [18F]-AV-1451 binding profile in chronic traumatic encephalopathy: a postmortem case series. Acta Neuropathologica Communications 2019, 7: 164. PMID: 31661038, PMCID: PMC6816221, DOI: 10.1186/s40478-019-0808-1.Peer-Reviewed Original ResearchConceptsTau aggregationPositron emission tomographyTau lesionsPresence of tau aggregatesInferior parietal cortexSuperior temporal cortexPaired helical filamentsTau seeding activityHyperphosphorylated tau speciesDetection of tau aggregatesTraumatic encephalopathyPostmortem brain tissue samplesCorticobasal degenerationProgressive supranuclear palsyBinding profilesTau-containing lesionsRepetitive head traumaDifferential binding affinityFrontal cortexTemporal cortexParietal cortexTau conformationTau speciesBinding affinityOccipital cortexEvaluation of pharmacokinetic modeling strategies for in-vivo quantification of tau with the radiotracer [18F]MK6240 in human subjects
Guehl N, Wooten D, Yokell D, Moon S, Dhaynaut M, Katz S, Moody K, Gharagouzloo C, Kas A, Johnson K, El Fakhri G, Normandin M. Evaluation of pharmacokinetic modeling strategies for in-vivo quantification of tau with the radiotracer [18F]MK6240 in human subjects. European Journal Of Nuclear Medicine And Molecular Imaging 2019, 46: 2099-2111. PMID: 31332496, PMCID: PMC6709592, DOI: 10.1007/s00259-019-04419-z.Peer-Reviewed Original ResearchConceptsReference tissue methodDistribution volume ratioTissue methodIn vivo quantificationPharmacokinetic modeling strategiesArterial plasma input functionMultilinear reference tissue methodsTwo-tissue compartment modelBlood:plasma ratioTissue-to-plasmaPlasma input functionPlasma concentration time courseBlood-based methodMethodsThirty-five subjectsSUV ratioBlood-based analysesData setsArterial input functionPET scansControl subjectsMild cognitive impairmentPlasma ratioRadiometabolite analysisHealthy controlsConcentration time courseAutoradiography validation of novel tau PET tracer [F-18]-MK-6240 on human postmortem brain tissue
Aguero C, Dhaynaut M, Normandin M, Amaral A, Guehl N, Neelamegam R, Marquie M, Johnson K, El Fakhri G, Frosch M, Gomez-Isla T. Autoradiography validation of novel tau PET tracer [F-18]-MK-6240 on human postmortem brain tissue. Acta Neuropathologica Communications 2019, 7: 37. PMID: 30857558, PMCID: PMC6410510, DOI: 10.1186/s40478-019-0686-6.Peer-Reviewed Original ResearchConceptsIn vivo detection of neurofibrillary tanglesNeurofibrillary tanglesDetection of neurofibrillary tanglesAlzheimer's diseaseTDP-43Binds to neurofibrillary tanglesFrontotemporal lobar degeneration-tauOff-target bindingDNA-binding protein 43Binding patternsNon-Alzheimer tauopathiesHuman postmortem brain tissueTau aggregationPostmortem brain tissueBinding signalBinding targetsCerebral amyloid angiopathyIn vivo detectionB-amyloidNeurodegenerative diseasesHuman brain tissueTauTau positron emission tomographyBindingMK-6240