Publications by authors named "M Donahue"

Background: Central synucleinopathies, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), involve alpha-synuclein accumulation and dopaminergic cell loss in the substantia nigra (SN) and locus coeruleus (LC). Pure autonomic failure (PAF), a peripheral synucleinopathy, often precedes central synucleinopathies.

Objectives: To assess early brain involvement in PAF using neuromelanin-sensitive magnetic resonance imaging (NM-MRI) and fluorodopa-positron emission tomography (FDOPA-PET), and to determine whether PAF patients with a high likelihood ratio (LR) for conversion to a central synucleinopathy exhibit reduced NM-MRI contrast in the LC and SN compared with controls and low-LR patients.

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Moyamoya is a non-atherosclerotic intracranial steno-occlusive condition that places patients at high risk for ischaemic stroke. Randomized trials of surgical revascularization demonstrating efficacy in ischaemic moyamoya have not been performed, and as such, biomarkers of parenchymal haemodynamic impairment are needed to assist with triage and evaluate post-surgical response. In this prospective study, we test the hypothesis that parenchymal cerebrovascular reactivity (CVR) metrics in response to a fixed-inspired 5% carbon dioxide challenge correlate with recent focal ischaemic symptoms.

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Identifying processes that promote coral reef recovery and resilience is crucial as ocean warming becomes more frequent and severe. Sexual reproduction is essential for the replenishment of coral populations and maintenance of genetic diversity; however, the ability for corals to reproduce may be impaired by marine heatwaves that cause coral bleaching. In 2014 and 2015, the Hawaiian Islands experienced coral bleaching with differential bleaching susceptibility in the species Montipora capitata, a dominant reef-building coral in the region.

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Hippocampal region CA2 is essential for social memory processing. Interaction with social stimuli induces changes in CA2 place cell firing during active exploration and sharp wave-ripples during rest following a social interaction. However, it is unknown whether these changes in firing patterns are caused by integration of multimodal social stimuli or by a specific sensory modality associated with a social interaction.

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Background And Objectives: Sickle cell disease (SCD) is a hemoglobinopathy resulting in hemoglobin-S production, hemolytic anemia, and elevated stroke risk. Treatments include oral hydroxyurea, blood transfusions, and hematopoietic stem cell transplantation (HSCT). Our objective was to evaluate the neurologic relevance of these therapies by characterizing how treatment-induced changes in hemoglobin (Hb) affect brain health biomarkers.

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