Publications by authors named "Davin A"

Deep brain stimulation is a well-established treatment for improving motor symptoms in Parkinson's disease. However, persistent non-motor symptoms, such as excessive daytime sleepiness, remain a significant challenge and necessitate further investigation. In this study, we conducted repeated measurements of daytime sleepiness using a modified multiple sleep latency test in a healthy monkey (macaca fascicularis), which was later rendered parkinsonian through MPTP administration.

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Alzheimer's disease (AD) is a neurodegenerative disorder that progressively involves brain regions with an often-predictable pattern. Damage to the brain appears to spread and worsen with time, but the molecular mechanisms underlying the region-specific distribution of AD pathology at different stages of the disease are still under-investigated. In this study, a whole-transcriptome analysis was carried out on brain samples from the hippocampus (HI), temporal and parietal cortices (TC and PC, respectively), cingulate cortex (CG), and substantia nigra (SN) of six subjects with a definite AD diagnosis and three healthy age-matched controls in duplicate.

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  • Poststroke cognitive impairment is common, but the exact changes in cognitive function following a first stroke compared to pre-stroke levels are not fully understood.
  • The study aimed to track cognitive performance over time in stroke survivors versus individuals without strokes, using data from 14 international cohorts of older adults.
  • Results showed that incident stroke led to a significant immediate drop in overall cognitive skills and accelerated decline in cognitive abilities over time.
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  • The study investigates how cardiometabolic multimorbidity (CMM) and depression affect cognitive function in older adults, aiming to understand their individual and combined impacts.
  • It harmonizes data from 14 international cohort studies and utilizes various scales to assess CMM and depression among participants who did not have dementia at the start of the study.
  • Findings include the analysis of over 30,000 older adults, revealing that both CMM and depression are linked to cognitive decline, with further validation through additional studies across different settings.
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  • Previous studies suggest that using antihypertensive medication in older adults may lower the overall risk of dementia, but the effects on different types of dementia, particularly Alzheimer’s disease (AD), are still uncertain.
  • This research analyzed data from over 31,000 participants across multiple countries, focusing on how history of hypertension and blood pressure levels impact the risk of developing AD and non-AD types of dementia.
  • The findings indicated that untreated hypertension significantly increases the risk of developing AD and non-AD dementia compared to healthy individuals, while treated hypertension showed a similar risk for non-AD but not a significant difference between treated and untreated groups.
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APOE ε4 allele is the major genetic risk factor for Alzheimer's Disease (AD). Furthermore, APOE methylation pattern has been described to be associated with the disease and to follow a bimodal pattern, with a hypermethylated CpG island and a hypomethylated promoter region. However, little is known about the methylation levels in the APOE 5'UTR region.

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  • Phylogenetic reconciliation is a method used to study how gene trees evolve in relation to species trees, helping to explain changes through events like gene duplications and losses.
  • This approach is beneficial for understanding genome evolution, aiding in tasks such as inferring ancestral gene content and analyzing metabolic evolution across microbial lineages.
  • There are many opportunities to expand this method in microbiology, including improving models for realism, scalability, and integrating ecological factors to enhance our understanding of microbial diversity.
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Introduction: The LIfestyle for BRAin Health (LIBRA) index yields a dementia risk score based on modifiable lifestyle factors and is validated in Western samples. We investigated whether the association between LIBRA scores and incident dementia is moderated by geographical location or sociodemographic characteristics.

Methods: We combined data from 21 prospective cohorts across six continents (N = 31,680) and conducted cohort-specific Cox proportional hazard regression analyses in a two-step individual participant data meta-analysis.

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The central nervous system (CNS) is surrounded by three membranes called meninges. Specialised fibroblasts, originating from the mesoderm and neural crest, primarily populate the meninges and serve as a binding agent. Our goal was to compare fibroblasts from meninges and skin obtained from the same human-aged donors, exploring their molecular and cellular characteristics related to CNS functions.

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The timing of early cellular evolution, from the divergence of Archaea and Bacteria to the origin of eukaryotes, is poorly constrained. The ATP synthase complex is thought to have originated prior to the Last Universal Common Ancestor (LUCA) and analyses of ATP synthase genes, together with ribosomes, have played a key role in inferring and rooting the tree of life. We reconstruct the evolutionary history of ATP synthases using an expanded taxon sampling set and develop a phylogenetic cross-bracing approach, constraining equivalent speciation nodes to be contemporaneous, based on the phylogenetic imprint of endosymbioses and ancient gene duplications.

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Importance: The utility of antihypertensives and ideal blood pressure (BP) for dementia prevention in late life remains unclear and highly contested.

Objectives: To assess the associations of hypertension history, antihypertensive use, and baseline measured BP in late life (age >60 years) with dementia and the moderating factors of age, sex, and racial group.

Data Source And Study Selection: Longitudinal, population-based studies of aging participating in the Cohort Studies of Memory in an International Consortium (COSMIC) group were included.

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Article Synopsis
  • - ALE and GeneRax are tools designed for analyzing how gene trees relate to species trees, using statistical models to understand events like gene duplication, transfer, and loss, while also helping to determine the origins of gene families and root species trees.
  • - Despite recent criticisms regarding their reliability in estimating gene duplication and transfer events, a study found that ALE and GeneRax perform well on both simulated data and real-world empirical data.
  • - Specifically, ALE demonstrates a consistent ability to capture variations in gene event frequencies according to known biological contexts, successfully rooting species trees in plants and opisthokonts, while providing comparable insights for Bacteria.
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Introduction: Sex differences in dementia risk, and risk factor (RF) associations with dementia, remain uncertain across diverse ethno-regional groups.

Methods: A total of 29,850 participants (58% women) from 21 cohorts across six continents were included in an individual participant data meta-analysis. Sex-specific hazard ratios (HRs), and women-to-men ratio of hazard ratios (RHRs) for associations between RFs and all-cause dementia were derived from mixed-effect Cox models.

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Patients with Parkinson's disease often complain of excessive daytime sleepiness which negatively impacts their quality of life. The pedunculopontine nucleus, proposed as a target for deep brain stimulation to improve freezing of gait in Parkinson's disease, is also known to play a key role in the arousal system. Thus, the putative control of excessive daytime sleepiness by pedunculopontine nucleus area stimulation merits exploration for treating Parkinson's disease patients.

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Background: Frailty is a complex, multi-dimensional age-related syndrome that increases the susceptibility to adverse health outcomes and poor quality of life. A growing consensus supports the contribution of chronic inflammation and immune system alterations to frailty, however a clear role of such alterations remains to be elucidated. Furthermore, pro- and anti-inflammatory cytokines together with other signaling molecules might spread from activated cells to the adjacent ones through extracellular vesicles (EVs), which have also a role in cellular aging.

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  • Parkinson's disease can cause sleep problems that start early, even before the shaking and trouble moving show up.
  • In a study with macaque monkeys, scientists monitored their sleep patterns using special equipment while slowly giving them a substance that mimics Parkinson's disease.
  • They found that the monkeys had worse sleep at night and felt sleepy during the day way before any motor issues started, which means sleep problems are important to study for understanding the disease better.
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Interpreting phylogenetic trees requires a root, which provides the direction of evolution and polarizes ancestor-descendant relationships. But inferring the root using genetic data is difficult, particularly in cases where the closest available outgroup is only distantly related, which are common for microbes. In this chapter, we present a workflow for estimating rooted species trees and the evolutionary history of the gene families that evolve within them using probabilistic gene tree-species tree reconciliation.

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Many organisms are able to incorporate exogenous DNA into their genomes. This process, called lateral gene transfer (LGT), has the potential to benefit the recipient organism by providing useful coding sequences, such as antibiotic resistance genes or enzymes which expand the organism's metabolic niche. For evolutionary biologists, LGTs have often been considered a nuisance because they complicate the reconstruction of the underlying species tree that many analyses aim to recover.

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Alzheimer's disease (AD) and Lewy body dementia (LBD) are two different forms of dementia, but their pathology may involve the same cortical areas with overlapping cognitive manifestations. Nonetheless, the clinical phenotype is different due to the topography of the lesions driven by the different underlying molecular processes that arise apart from genetics, causing diverse neurodegeneration. Here, we define the commonalities and differences in the pathological processes of dementia in two kindred cases, a mother and a son, who developed classical AD and an aggressive form of AD/LBD, respectively, through a neuropathological, genetic (next-generation sequencing), and transcriptomic (RNA-seq) comparison of four different brain areas.

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Frailty is an important age-related syndrome associated with several adverse health outcomes. Its biological basis is undefined. Raised plasma homocysteine (HOcy) is an established risk factor for cardiovascular disease, dementia, cognitive impairment, and mortality, but little is known about the possible role of plasma HOcy, cyanocobalamin (B12), and folate (FO levels in the development of frailty.

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Background: Education and occupational complexity are main sources of mental engagement during early life and adulthood respectively, but research findings are not conclusive regarding protective effects of these factors against late-life dementia.

Objective: This project aimed to examine the unique contributions of education and occupational complexity to incident dementia, and to assess the mediating effects of occupational complexity on the association between education and dementia across diverse cohorts.

Method: We used data from 10,195 participants (median baseline age = 74.

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The multitasking nature of lncRNAs allows them to play a central role in both physiological and pathological conditions. Often the same lncRNA can participate in different diseases. Specifically, the MYC-induced Long non-Coding RNA MINCR is upregulated in various cancer types, while downregulated in Amyotrophic Lateral Sclerosis patients.

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Since the association of SARS-Cov-2 infection with Nervous System (NS) manifestations, we performed RNA-sequencing analysis in Frontal Cortex of COVID-19 positive or negative individuals and affected or not by Dementia individuals. We examined gene expression differences in individuals with COVID-19 and Dementia compared to Dementia only patients by collecting transcript counts in each sample and performing Differential Expression analysis. We found eleven genes satisfying our significance criteria, all of them being protein coding genes.

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Frailty syndrome is an age-related condition involving a loss of resilience, susceptibility to adverse health outcomes, and poor quality of life. This study was conducted in the framework of InveCe.Ab, an ongoing longitudinal population-based study.

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