Role of Biomarkers for the Diagnosis of Prion Diseases: A Narrative Review.

Prion diseases are progressive and irreversible neurodegenerative disorders with a low incidence (1.5-2 cases per million per year). Genetic (10-15%), acquired (anecdotal) and sporadic (85%) forms of the disease have been described.

Progressive cognitive impairment and familial spastic paraparesis due to PRESENILIN 1 mutation: anatomoclinical characterization.

Introduction: Autosomal dominant Alzheimer's disease (ADAD) due to presenilin 1 (PSEN1) mutation can induce atypical neurological symptoms such as movement disorders and epileptic seizures in the context of early-onset progressive cognitive impairment.

Methods: This study includes the anatomoclinical description of three patients of two generations of the same family with movement disorders and progressive cognitive impairment. All were evaluated by trained neurologists, underwent protocolized neuropsychological evaluation, and were assessed by structural (magnetic resonance) and functional (SPECT, PET-18FDG, or PET-18F-Florbetapir) brain imaging tests.

Alzheimer's disease research progress in the Mediterranean region: The Alzheimer's Association International Conference Satellite Symposium.

As research and services in the Mediterranean region continue to increase, so do opportunities for global collaboration. To support such collaborations, the Alzheimer's Association was due to hold its seventh Alzheimer's Association International Conference Satellite Symposium in Athens, Greece in 2021. Due to the COVID-19 pandemic, the meeting was held virtually, which enabled attendees from around the world to hear about research efforts in Greece and the surrounding Mediterranean countries.

Parsing heterogeneity within dementia with Lewy bodies using clustering of biological, clinical, and demographic data.

Background: Dementia with Lewy bodies (DLB) includes various core clinical features that result in different phenotypes. In addition, Alzheimer's disease (AD) and cerebrovascular pathologies are common in DLB. All this increases the heterogeneity within DLB and hampers clinical diagnosis.

Cognitive symptoms after COVID-19.

Introduction: SARS-CoV-2 infection frequently causes neurological symptoms. Cognitive alterations are among the most frequent symptoms, and may persist beyond the acute phase of infection.

Methods: We conducted a narrative review of the literature.

Validation of the LUMIPULSE automated immunoassay for the measurement of core AD biomarkers in cerebrospinal fluid.

Objectives: The core cerebrospinal fluid (CSF) biomarkers; total tau (tTau), phospho-tau (pTau), amyloid β 1-42 (Aβ 1-42), and the Aβ 1-42/Aβ 1-40 ratio have transformed Alzheimer's disease (AD) research and are today increasingly used in clinical routine laboratories as diagnostic tools. Fully automated immunoassay instruments with ready-to-use assay kits and calibrators has simplified their analysis and improved reproducibility of measurements. We evaluated the analytical performance of the fully automated immunoassay instrument LUMIPULSE G (Fujirebio) for measurement of the four core AD CSF biomarkers and determined cutpoints for AD diagnosis.

State-of-the-art of lumbar puncture and its place in the journey of patients with Alzheimer's disease.

Recent advances in developing disease-modifying therapies (DMT) for Alzheimer's disease (AD), and the recognition that AD pathophysiology emerges decades before clinical symptoms, necessitate a paradigm shift of health-care systems toward biomarker-guided early detection, diagnosis, and therapeutic decision-making. Appropriate incorporation of cerebrospinal fluid biomarker analysis in clinical practice is an essential step toward system readiness for accommodating the demand of AD diagnosis and proper use of DMTs-once they become available. However, the use of lumbar puncture (LP) in individuals with suspected neurodegenerative diseases such as AD is inconsistent, and the perception of its utility and safety differs considerably among medical specialties as well as among regions and countries.

Distinctive Oculomotor Behaviors in Alzheimer's Disease and Frontotemporal Dementia.

Oculomotor behavior can provide insight into the integrity of widespread cortical networks, which may contribute to the differential diagnosis between Alzheimer's disease and frontotemporal dementia. Three groups of patients with Alzheimer's disease, behavioral variant of frontotemporal dementia (bvFTD) and semantic variant of primary progressive aphasia (svPPA) and a sample of cognitively unimpaired elders underwent an eye-tracking evaluation. All participants in the discovery sample, including controls, had a biomarker-supported diagnosis.

The AT(N) framework for Alzheimer's disease in adults with Down syndrome.

The National Institute on Aging in conjunction with the Alzheimer's Association (NIA-AA) recently proposed a biological framework for defining the Alzheimer's disease (AD) continuum. This new framework is based upon the key AD biomarkers (amyloid, tau, neurodegeneration, AT[N]) instead of clinical symptoms and represents the latest understanding that the pathological processes underlying AD begin decades before the manifestation of symptoms. By using these same biomarkers, individuals with Down syndrome (DS), who are genetically predisposed to developing AD, can also be placed more precisely along the AD continuum.

The combined effect of amyloid-β and tau biomarkers on brain atrophy in dementia with Lewy bodies.

Background: Alzheimer's disease (AD)-related pathology is frequently found in patients with dementia with Lewy bodies (DLB). However, it is unknown how amyloid-β and tau-related pathologies influence neurodegeneration in DLB. Understanding the mechanisms underlying brain atrophy in DLB can improve our knowledge about disease progression, differential diagnosis, drug development and testing of anti-amyloid and anti-tau therapies in DLB.

Periodontal disease as a possible cause for Alzheimer's disease.

Approximately 47 million people worldwide have been diagnosed with dementia, 60%-80% of whom have dementia of the Alzheimer's disease type. Unfortunately, there is no cure in sight. Defining modifiable risk factors for Alzheimer's disease may have a significant impact on its prevalence.

CCL23: A Chemokine Associated with Progression from Mild Cognitive Impairment to Alzheimer's Disease.

CCL23 is a chemokine implicated in inflammation and host defense responses. It has been recently associated with acquired brain damage and stroke outcomes. In this study, we reported the role of CCL23 in Alzheimer's disease (AD).

Assessing general cognitive and adaptive abilities in adults with Down syndrome: a systematic review.

Background: Measures of general cognitive and adaptive ability in adults with Down syndrome (DS) used by previous studies vary substantially. This review summarises the different ability measures used previously, focusing on tests of intelligence quotient (IQ) and adaptive behaviour (AB), and where possible examines floor effects and differences between DS subpopulations. We aimed to use information regarding existing measures to provide recommendations for individual researchers and the DS research community.

Agreement of amyloid PET and CSF biomarkers for Alzheimer's disease on Lumipulse.

Objective: To determine the cutoffs that optimized the agreement between F-Florbetapir positron emission tomography (PET) and Aβ1-42, Aβ1-40, tTau, pTau and their ratios measured in cerebrospinal fluid (CSF) on the LUMIPULSE G600II instrument, we quantified the levels of these four biomarkers in 94 CSF samples from participants of the Sant Pau Initiative on Neurodegeneration (SPIN cohort) using the Lumipulse G System with available F-Florbetapir imaging.

Methods: Participants had mild cognitive impairment (n = 35), AD dementia (n = 12), other dementias or neurodegenerative diseases (n = 41), or were cognitively normal controls (n = 6). Levels of Aβ1-42 were standardized to certified reference material.

Down syndrome, Alzheimer disease, and cerebral amyloid angiopathy: The complex triangle of brain amyloidosis.

Down syndrome (DS) is the main genetic cause of intellectual disability worldwide. The overexpression of the Amyloid Precursor Protein, present in chromosome 21, leads to β-amyloid deposition that results in Alzheimer disease (AD) and, in most cases, also to cerebral amyloid angiopathy (CAA) neuropathology. People with DS invariably develop the neuropathological hallmarks of AD at the age of 40, and they are at an ultra high risk for suffering AD-related cognitive impairment thereafter.

Alzheimer's disease in Down syndrome: An overlooked population for prevention trials.

The discovery that adults with Down syndrome (DS) have neuropathological features identical to individuals with sporadic Alzheimer's disease (AD) played a key role in the identification of the amyloid precursor protein gene on chromosome 21 and resulted in the amyloid cascade hypothesis. Individuals with DS have a lifetime risk for dementia in excess of 90%, and DS is now acknowledged to be a genetic form of AD similar to rare autosomal-dominant causes. Just as DS put the spotlight on amyloid precursor protein mutations, it is also likely to inform us of the impact of manipulating the amyloid pathway on treatment outcomes in AD.

Obesity and Alzheimer's disease, does the obesity paradox really exist? A magnetic resonance imaging study.

Mid-life obesity is an established risk factor for Alzheimer's disease (AD) dementia, whereas late-life obesity has been proposed as a protective state. Weight loss, which predates cognitive decline, might explain this obesity paradox on AD risk. We aimed to assess the impact of late life obesity on brain structure taking into account weight loss as a potential confounder.

Altered topology of the functional speech production network in non-fluent/agrammatic variant of PPA.

Non-fluent/agrammatic primary progressive aphasia (nfvPPA) is caused by neurodegeneration within the left fronto-insular speech and language production network (SPN). Graph theory is a branch of mathematics that studies network architecture (topology) by quantifying features based on its elements (nodes and connections). This approach has been recently applied to neuroimaging data to explore the complex architecture of the brain connectome, though few studies have exploited this technique in PPA.

Plasma and CSF biomarkers for the diagnosis of Alzheimer's disease in adults with Down syndrome: a cross-sectional study.

Background: Diagnosis of Alzheimer's disease in Down syndrome is challenging because of the absence of validated diagnostic biomarkers. We investigated the diagnostic performance of plasma and CSF biomarkers in this population.

Methods: We did a cross-sectional study of adults aged 18 years and older with Down syndrome enrolled in a population-based health plan in Catalonia, Spain.

Consensus statement of the international summit on intellectual disability and Dementia related to post-diagnostic support.

Objectives: Post diagnostic support (PDS) has varied definitions within mainstream dementia services and different health and social care organizations, encompassing a range of supports that are offered to adults once diagnosed with dementia until death.

Method: An international summit on intellectual disability and dementia held in Glasgow, Scotland in 2016 identified how PDS applies to adults with an intellectual disability and dementia. The Summit proposed a model that encompassed seven focal areas: post-diagnostic counseling; psychological and medical surveillance; periodic reviews and adjustments to the dementia care plan; early identification of behaviour and psychological symptoms; reviews of care practices and supports for advanced dementia and end of life; supports to carers/ support staff; and evaluation of quality of life.

Risk factors are different for deep and lobar remote hemorrhages after intravenous thrombolysis.

Background And Purpose: Remote parenchymal haemorrhage (rPH) after intravenous thrombolysis is defined as hemorrhages that appear in brain regions without visible ischemic damage, remote from the area of ischemia causing the initial stroke symptom. The pathophysiology of rPH is not clear and may be explained by different underlying mechanisms. We hypothesized that rPH may have different risk factors according to the bleeding location.

Longitudinal brain structural changes in preclinical Alzheimer's disease.

Introduction: Brain structural changes in preclinical Alzheimer's disease (AD) are poorly understood.

Methods: We compared the changes in cortical thickness in the ADNI cohort during a 2-year follow-up between the NIA-AA preclinical AD stages defined by cerebrospinal fluid (CSF) biomarker levels. We also analyzed the correlation between baseline CSF biomarkers and cortical atrophy rates.

Neuronal exosomes reveal Alzheimer's disease biomarkers in Down syndrome.

Introduction: Individuals with Down syndrome (DS) exhibit Alzheimer's disease (AD) neuropathology and dementia early in life. Blood biomarkers of AD neuropathology would be valuable, as non-AD intellectual disabilities of DS and AD dementia overlap clinically. We hypothesized that elevations of amyloid β (Aβ) peptides and phosphorylated-tau in neuronal exosomes may document preclinical AD.

Reduced Slow-Wave Sleep Is Associated with High Cerebrospinal Fluid Aβ42 Levels in Cognitively Normal Elderly.

Study Objectives: Emerging evidence suggests a role for sleep in contributing to the progression of Alzheimer disease (AD). Slow wave sleep (SWS) is the stage during which synaptic activity is minimal and clearance of neuronal metabolites is high, making it an ideal state to regulate levels of amyloid beta (Aβ). We thus aimed to examine relationships between concentrations of Aβ42 in the cerebrospinal fluid (CSF) and measures of SWS in cognitively normal elderly subjects.