Memantine Improves Attentional Processes in Fragile X-Associated Tremor/Ataxia Syndrome: Electrophysiological Evidence from a Randomized Controlled Trial.

Progressive cognitive deficits are common in patients with fragile X-associated tremor/ataxia syndrome (FXTAS), with no targeted treatment yet established. In this substudy of the first randomized controlled trial for FXTAS, we examined the effects of NMDA antagonist memantine on attention and working memory. Data were analyzed for patients (24 in each arm) who completed both the primary memantine trial and two EEG recordings (at baseline and follow-up) using an auditory "oddball" task. Results demonstrated significantly improved attention/working memory performance after one year only for the memantine group. The event-related potential P2 amplitude elicited by non-targets was significantly enhanced in the treated group, indicating memantine-associated improvement in attentional processes at the stimulus identification/discrimination level. P2 amplitude increase was positively correlated with improvement on the behavioral measure of attention/working memory during target detection. Analysis also revealed that memantine treatment normalized the P2 habituation effect at the follow-up visit. These findings indicate that memantine may benefit attentional processes that represent fundamental components of executive function/dysfunction, thought to comprise the core cognitive deficit in FXTAS. The results provide evidence of target engagement of memantine, as well as therapeutically relevant information that could further the development of specific cognitive or disease-modifying therapies for FXTAS

Primary carcinoid tumors of the liver

Background: Primary carcinoid tumors of the liver are uncommon and rarely symptomatic. The diagnosis of primary hepatic etiology requires rigorous workup and continued surveillance to exclude a missed primary. Case Presentation: We present a case of a 62-year-old female with a primary hepatic carcinoid tumor successfully resected, now with three years of disease-free follow-up. We present a review of the current literature regarding the diagnosis, pathology, management, and natural history of this disease entity. Conclusion: Primary carcinoid tumors of the liver are rare, therefore classifying their nature as primary hepatic in nature requires extensive workup and prolonged follow-up. All neuroendocrine tumors have an inherent malignant potential that must be recognized. Management remains surgical resection, with several alternative options available for non-resectable tumors and severe symptoms. The risk of recurrence of primary hepatic carcinoid tumors after resection remains unknown

A Clinical Trial to Validate Event-Related Potential Markers of Alzheimer\u27s Disease in Outpatient Settings

INTRODUCTION: We investigated whether event-related potentials (ERP) collected in outpatient settings and analyzed with standardized methods can provide a sensitive and reliable measure of the cognitive deficits associated with early Alzheimer\u27s disease (AD). METHODS: A total of 103 subjects with probable mild AD and 101 healthy controls were recruited at seven clinical study sites. Subjects were tested using an auditory oddball ERP paradigm. RESULTS: Subjects with mild AD showed lower amplitude and increased latency for ERP features associated with attention, working memory, and executive function. These subjects also had decreased accuracy and longer reaction time in the target detection task associated with the ERP test. DISCUSSION: Analysis of ERP data showed significant changes in subjects with mild AD that are consistent with the cognitive deficits found in this population. The use of an integrated hardware/software system for data acquisition and automated data analysis methods make administration of ERP tests practical in outpatient settings

Diagnosis of Dementia with Lewy Bodies: Fluctuations, Biomarkers, and Beyond

Dementia with Lewy bodies (DLB), the second most common cause of dementia, remains a difficult condition to accurately diagnose and manage. Variable involvement of motor and cognitive functions, plus psychiatric and behavioral symptoms, contributes to the difficulty in managing DLB. Additionally, DLB can cause severe sleep disruption through REM sleep behavior disorder, autonomic symptoms, disruptions of olfaction/taste and mood, hallucinations, and more. In this chapter, advances and remaining challenges in the diagnosis of DLB are discussed, including a review of the current consensus criteria for DLB. The spectrum of disorders with Lewy bodies (LBs) are described including their wide-range of clinical presentations and overlap with Alzheimer’s disease (AD) and Parkinson’s disease with and without dementia. Particular consideration is given to advancements in quantification of cognitive fluctuations through improved clinical instruments, EEG, and other advanced biomarkers. Detection of DLB has improved, but establishing the “primary” pathology in cases with concomitant LB andd AD remains difficult. Likelihood of a clinical DLB syndrome is thought to be a function of distribution of LBs and severity of AD-type pathology. Further work is needed to better understand LB disease subtypes and the underlying pathophysiological mechanisms to allow for more targeted and comprehensive therapies

What Electrophysiology Tells Us About Alzheimer’s Disease::A Window into the Synchronization and Connectivity of Brain Neurons

Electrophysiology provides a real-time readout of neural functions and network capability in different brain states, on temporal (fractions of milliseconds) and spatial (micro, meso, and macro) scales unmet by other methodologies. However, current international guidelines do not endorse the use of electroencephalographic (EEG)/magnetoencephalographic (MEG) biomarkers in clinical trials performed in patients with Alzheimer’s disease (AD), despite a surge in recent validated evidence. This Position Paper of the ISTAART Electrophysiology Professional Interest Area endorses consolidated and translational electrophysiological techniques applied to both experimental animal models of AD and patients, to probe the effects of AD neuropathology (i.e., brain amyloidosis, tauopathy, and neurodegeneration) on neurophysiological mechanisms underpinning neural excitation/inhibition and neurotransmission as well as brain network dynamics, synchronization, and functional connectivity reflecting thalamocortical and cortico-cortical residual capacity. Converging evidence shows relationships between abnormalities in EEG/MEG markers and cognitive deficits in groups of AD patients at different disease stages. The supporting evidence for the application of electrophysiology in AD clinical research as well as drug discovery pathways warrants an international initiative to include the use of EEG/MEG biomarkers in the main multicentric projects planned in AD patients, to produce conclusive findings challenging the present regulatory requirements and guidelines for AD studies

Treatment of fragile X-associated tremor ataxia syndrome (FXTAS) and related neurological problems

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a progressive neurological disorder that affects older adult carriers, predominantly males, of premutation alleles (55 to 200 CGG repeats) of the fragile X (FMR1) gene. Principal features of FXTAS are intention tremor, ataxia, parkinsonism, cognitive decline, and peripheral neuropathy; ancillary features include, autonomic dysfunction, and psychiatric symptoms of anxiety, depression, and disinhibition. Although controlled trials have not been carried out in individuals with FXTAS, there is a significant amount of anecdotal information regarding various treatment modalities. Moreover, there exists a great deal of evidence regarding the efficacy of various medications for treatment of other disorders (eg, Alzheimer disease) that have substantial phenotypic overlap with FXTAS. The current review summarizes what is currently known regarding the symptomatic treatment, or potential for treatment, of FXTAS