Basic Science and Pathogenesis.

Background: Pneumococcal meningitis is a type of meningitis that may face long-term neurological complications, leading to the hypothesis that it might contribute to the deposition of beta-amyloid (Aβ) and predispose individuals to Alzheimer's pathology.

Method: Male and female APP/PS1 mice, 50 days old, were divided into control (n = 5) and meningitis (n = 6). Under anesthesia, an intracisternal injection of either artificial cerebrospinal fluid (CSF) as a placebo or 5 × 10 colony-forming units (CFU) of S.

Basic Science and Pathogenesis.

Background: Aging, tau pathology, and chronic inflammation in the brain play crucial roles in neuroinflammation, synaptic loss, neurodegeneration, and cognitive decline in tauopathies, such as Alzheimer's disease. However, the molecular mechanisms that trigger aberrant chronic inflammatory signaling in tauopathies are poorly understood.

Method: We utilized brain tissues from tauopathy patients and the tauopathy mouse models.

Basic Science and Pathogenesis.

Background: Alzheimer's disease (AD) is a neurogenerative disease that affect millions worldwide with no effective treatment. Several studies have been conducted to decipher to genomic underpinnings of AD. Due to its complex nature, many genes have been found to be associated with AD.

Basic Science and Pathogenesis.

Background: Alzheimer's disease (AD) is characterized by the accumulation of tau protein in the brain, which forms neurofibrillary tangles and contributes to the gradual deterioration of brain function. As a consequence, cellular senescence occurs, leading to cognitive impairment and hastening the aging process. Immunotherapies targeting Aβ and other protein aggregates are also being developed in the meantime.

Development of a reference standard to assign bacterial versus viral infection etiology using an all-inclusive methodology for comparison of novel diagnostic tool performance.

Background: Diagnostic test evaluation requires a reference standard. We describe an approach for creating a reference standard for acute infection using unrestricted adjudication and apply it to compare biomarker tools.

Methods: Adults and children with suspected acute infection enrolled in three prospective studies at emergency departments and urgent cares were included.

Basic Science and Pathogenesis.

Background: Clear sex differences exist in AD and PD. Several studies examined genetic regulations for AD phenotypes and gene expression data in a sex-specific manner, identifying some differences between males and females. In contrasts, although proteins are final effectors of most physiological pathways and important drug targets, sex-specific regulations for proteins remain vastly understudied.

Clinical Manifestations.

Background: Older adults increasingly rely on digital technologies to perform instrumental activities of daily living (iADLs), including commerce, managing accounts online, using texting and websites for social connection, and accessing health services via web platforms. Despite the increasingly central role of technology to daily life, current iADL measures do not regularly capture the digital approach to daily activities. The current study had three broad aims 1) determine the applicability of technology-based iADLs to the daily lives of older adults being evaluated for Alzheimer's disease and related dementias (ADRD), 2) compare the level of dependence for tech and traditional iADL items, and 3) determine if adding technology related iADL items improves the diagnostic accuracy of iADL assessments.

Clinical Manifestations.

Background: The progression of Alzheimer's disease and related dementias (ADRDs) from prodromal state to dementia syndrome prompts researchers to identify early markers of cognitive decline. One potential risk marker is subjective memory concerns (SMCs). Individuals with greater perceived stress often report more cognitive concerns.

Clinical Manifestations.

Background: The concept of motoric cognitive risk (MCR) combines subjective cognitive concern (SCC) with slowed gait speed. The concept allows for the incorporation of cognitive and functional slowing into a measure of risk assessment. This study explores differences in cognitive functioning in cognitively unimpaired older adults with MCR and those without subjective cognitive concern and without slow gait speed.

Basic Science and Pathogenesis.

Background: Our studies show that the small non-coding RNA, mir20a-3p, is neuroprotective for stroke in the acute phase and also attenuates long term cognitive decline in middle-aged female rats. Cognitive decline due to vascular diseases, such as stroke, is associated with secondary neurodegeneration in cortex and limbic structures. In this study, we assessed the volume of white matter, ventricles and regional diffusion-weighted MR imaging measures to delineate pathological tissue characteristics from the postmortem brain of stroke rats.

Clinical Manifestations.

Background: Mild cognitive function (MCI) is associated with a declined short-term memory (STM). This study compared STM between adults with MCI and normal cognition assessed by verbal memory vs visuospatial memory.

Methods: Sixteen subjects with MCI and 11 subjects with normal cognition gave their written consent to participate in the study which was approved by the North Texas Regional IRB.

Basic Science and Pathogenesis.

Background: Alzheimer's disease (AD) is characterized by the accumulation of amyloid-beta (Aβ) in the extracellular space, which leads to various adverse effects such as oxidative stress, neuroinflammation, mitochondrial dysfunction, tau phosphorylation, synapse loss, and neurodegeneration. Therefore, therapeutic interventions that can reduce Aβ-toxicity and slow down the progression of cognitive dysfunction in AD have significance. One promising approach is to use extracellular vesicles (EVs) that are released by neural stem cells (NSCs) derived from human induced pluripotent stem cells (hiPSCs).

Clinical Manifestations.

Background: Family history of Alzheimer's disease (AD) or undiagnosed memory problems is linked to an increased risk of dementia. Subjective memory complaints are also more common among individuals with positive family history, which could be indicative of heightened awareness of memory deficits in these people. Here, we conducted an online study in cognitively normal individuals across the lifespan and aimed to examine whether the presence of family history is linked to worse objective memory performance that mediates the lower subjective memory in these individuals.

Clinical Manifestations.

Background: Nearly half the world's population is bi- or multilingual, where diverse interpretations of bilingualism with varying associated sociodemographic factors may lead to inconsistent conclusions in bilingualism and cognitive research and thus our study aimed to further examine this.

Method: We examined the sociodemographic features and bilingualism phenotypes among monolingual and bilingual individuals across three cohorts: Chinese American (CA) from UCSF Memory and Aging Center (n = 517), Mexican American (MA) from HABS-HD project (n = 1,166), and Indians (ID) from National Institute of Mental Health and Neuroscience (NIMHANS) (n = 1,233), encompassing individuals with normal cognition, mild cognitive impairment (MCI), and Alzheimer's dementia (AD). We compared group differences between monolinguals and bilinguals via Student's t-test for continuous variables and with Pearson's Chi-squared test for categorical variables.

Clinical Manifestations.

Background: Due to the shortage of healthcare professionals with expertise in diagnosis and treatment of Alzheimer disease and related dementias, there are long wait times to be evaluated in dementia specialty clinics and no clear guidance about how to allocate limited resources. The purpose of this study was to examine utility of cognitive screening measures administered by clinic staff to determine level of cognitive impairment to aid in decisions about which patients may benefit from full diagnostic services.

Methods: Participants were 169 older adults who completed an intake interview, including a brief cognitive screening test, conducted by a neuropsychologist at a dementia specialty clinic.

Clinical Manifestations.

Background: Previous findings evaluating longitudinal cognition in relation to the MeDi diet are inconsistent, and few studies have examined it in relation to the presence/absence of subjective cognitive decline (SCD). Our current aims are to test whether adherence to the MeDi diet is associated with the risk of clinical progression, future cognitive decline, and atrophy over time in Alzheimer's disease (AD)-sensitive regions in cognitively unimpaired (CU) older adults with or without SCD.

Methods: This longitudinal study includes 171 controls and 228 SCD patients recruited from memory clinics in the DELCODE study.

Clinical Manifestations.

Background: Recent research has highlighted the importance of sleep on cognitive processes. However, conflicting evidence exists regarding optimal sleep duration and the impact of other co-occurring conditions, such as depression. A diagnosis of depression in mid-life may increase the risk of developing dementia.

Clinical Manifestations.

Background: Motivational disturbances are a major harbinger for dementia, being associated with a two- to seven-fold higher conversion rate from mild cognitive impairment. However, there are currently no objective assessment methods for identifying motivational disturbances in older adults (OA). Here, we present preliminary findings from a larger study which aims to validate an objective behavioral measure of effort in OAs by investigating the effects of age, risk, and reward (gain vs.

Clinical Manifestations.

Background: African Americans (AA) are disproportionately affected by Long COVID, highlighting the need for targeted research to understand the enduring consequences of COVID-19 within this community. Among the array of symptoms associated with post-acute sequelae of SARS-CoV-2 (PASC), cognitive impairments emerge as a significant concern affecting up to 19% of COVID survivors. In this study, our goal is to comprehensively characterize the specific cognitive domains impacted in older AA adults.

Clinical Manifestations.

Background: Classical literature has pointed at lateralization of the relationship between memory scores and cerebral hemisphere injury. Epilepsy studies have suggested an association between left hippocampal damage and verbal memory deficits, and between right hippocampal damage and visual memory deficits. We aimed to explore this concept in the context of tauopathy due to Alzheimer's disease.

Clinical Manifestations.

Background: Recent studies showed that neuroinflammation plays a key role in triggering specific neuropsychiatric symptoms (NPS), such as irritability and agitation, in individuals with Alzheimer's disease (AD). While prior studies showed an association between tau pathology and all NPS domains, the extent to which tau influences each specific NPS domain remains unclear. Here, we aim to investigate the association of tau and NPS domains in the AD continuum.

Clinical Manifestations.

Background: While the functioning of semantic memory has been extensively documented in Alzheimer disease (AD), little is known about semantic control capacities that monitor and modulate semantic representations. The present study used a task to assess semantic control in typical and atypical AD patients.

Method: 11 patients with typical AD (ADtyp), 17 patients with logopenic variant of primary progressive aphasia (lvPPA, i.

Clinical Manifestations.

Background: We have previously shown that there are 3 unique behavioral symptom clusters, or groupings of temporally related co-occurring behavioral and psychological symptoms (BPSD) representing how an individual's daily BPSD group together relative to their own typical BPSD manifestation across a 21-day period. To further validate these symptom cluster concepts, we examined whether they are predicted by different environmental triggers.

Method: Family caregivers completed daily diary surveys for 8 consecutive days reporting on the physical, social and care environment in addition to their care recipients different BPSD.

Clinical Manifestations.

Background: Alzheimer's disease and related dementias (ADRD) are characterized by impairments in an individual's cognitive and functional abilities. Computerized cognitive tests have been shown to be effective in detecting mild cognitive impairment and ADRD but whether they can stage the ADRD disease remains to be studied.

Method: Retrospective analysis was performed on a BrainCheck dataset containing 1,749 ADRD patients with different cognitive and functional assessments completed for cognitive care planning, including the Dementia Severity Rating Scale (DSRS), the Katz Index of Independence in Activities of Daily Living (ADL), and the BrainCheck cognitive assessment battery (BC-Assess).

Clinical Manifestations.

Background: Hispanic adults comprise 19% of the US population, yet <8% of Alzheimer's Disease and Related Dementia (ADRD) research cohorts. Hispanic adults in the US are 1.5 times more likely to develop ADRDs compared to Non-Hispanics.