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In vivo measures of tau burden are associated with atrophy in early Braak stage medial temporal lobe regions in amyloid-negative individuals

INTRODUCTION: It is unclear the degree to which tau pathology in the medial temporal lobe (MTL) measured by 18F-flortaucipir positron emission tomography relates to MTL subregional atrophy and whether this relationship differs between amyloid-β-positive and amyloid-β-negative individuals.METHODS: We analyzed correlation of MTL 18F-flortaucipir uptake with MTL subregional atrophy measured with high

Automated segmentation of medial temporal lobe subregions on in vivo T1-weighted MRI in early stages of Alzheimer's disease

Medial temporal lobe (MTL) substructures are the earliest regions affected by neurofibrillary tangle pathology-and thus are promising biomarkers for Alzheimer's disease (AD). However, automatic segmentation of the MTL using only T1-weighted (T1w) magnetic resonance imaging (MRI) is challenging due to the large anatomical variability of the MTL cortex and the confound of the dura mater, which is co

Structural and functional asymmetry of medial temporal subregions in unilateral temporal lobe epilepsy : A 7T MRI study

Mesial temporal lobe epilepsy (TLE) is a common neurological disorder affecting the hippocampus and surrounding medial temporal lobe (MTL). Although prior studies have analyzed whole-brain network distortions in TLE patients, the functional network architecture of the MTL at the subregion level has not been examined. In this study, we utilized high-resolution 7T T2-weighted magnetic resonance imag

Associative memory for conceptually unitized word pairs in mild cognitive impairment is related to the volume of the perirhinal cortex

Unitization, that is, the encoding of an association as one integrated entity, has been shown to improve associative memory in populations presenting with associative memory deficit due to hippocampal dysfunction, such as amnesic patients with focal hippocampal lesions and healthy older adults. One reason for this benefit is that encoding of unitized associations would rely on the perirhinal corte

Hippocampal sulcal cavities : prevalence, risk factors and association with cognitive performance. The SMART-Medea study and PREDICT-MR study

Hippocampal sulcal cavities (HSCs) are frequently observed on MRI, but their etiology and relevance is unclear. HSCs may be anatomical variations, or result from pathology. We assessed the presence of HSCs, and their cross-sectional association with demographics, vascular risk factors and cognitive functioning in two study samples. Within a random sample of 92 patients with vascular disease from t

Characterizing the human hippocampus in aging and Alzheimer's disease using a computational atlas derived from ex vivo MRI and histology

Although the hippocampus is one of the most studied structures in the human brain, limited quantitative data exist on its 3D organization, anatomical variability, and effects of disease on its subregions. Histological studies provide restricted reference information due to their 2D nature. In this paper, high-resolution (∼200 × 200 × 200 μm3) ex vivo MRI scans of 31 human hippocampal specimens are

Defining SNAP by cross-sectional and longitudinal definitions of neurodegeneration

INTRODUCTION: Suspected non-Alzheimer's pathophysiology (SNAP) is a biomarker driven designation that represents a heterogeneous group in terms of etiology and prognosis. SNAP has only been identified by cross-sectional neurodegeneration measures, whereas longitudinal measures might better reflect "active" neurodegeneration and might be more tightly linked to prognosis. We compare neurodegeneratio

Longitudinal and cross-sectional structural magnetic resonance imaging correlates of AV-1451 uptake

We examined the relationship between in vivo estimates of tau deposition as measured by 18F-AV-1451 tau positron emission tomography imaging and cross-sectional cortical thickness, as well as rates of antecedent cortical thinning measured from magnetic resonance imaging in individuals with and without evidence of cerebral amyloid in 63 participants from the Alzheimer's Disease Neuroimaging Initiat

Automated Multi-Atlas Segmentation of Hippocampal and Extrahippocampal Subregions in Alzheimer's Disease at 3T and 7T : What Atlas Composition Works Best?

BACKGROUND: Multi-atlas segmentation, a popular technique implemented in the Automated Segmentation of Hippocampal Subfields (ASHS) software, utilizes multiple expert-labelled images ("atlases") to delineate medial temporal lobe substructures. This multi-atlas method is increasingly being employed in early Alzheimer's disease (AD) research, it is therefore becoming important to know how the constr

Early Tau Burden Correlates with Higher Rate of Atrophy in Transentorhinal Cortex

Neurofibrillary tangle (NFT) pathology is linked to neurodegeneration in the medial temporal lobe (MTL). Using a tailored pipeline, we correlated atrophy rate, as measured from retrospective longitudinal MRI, with NFT burden, measured from 18F-AV-1451 PET, within MTL regions of earliest NFT pathology. In amyloid-β positive but not amyloid-β negative individuals, we found significant correlation be

Mapping the structural and functional network architecture of the medial temporal lobe using 7T MRI

Medial temporal lobe (MTL) subregions play integral roles in memory function and are differentially affected in various neurological and psychiatric disorders. The ability to structurally and functionally characterize these subregions may be important to understanding MTL physiology and diagnosing diseases involving the MTL. In this study, we characterized network architecture of the MTL in health

A protocol for manual segmentation of medial temporal lobe subregions in 7 Tesla MRI

Recent advances in MRI and increasing knowledge on the characterization and anatomical variability of medial temporal lobe (MTL) anatomy have paved the way for more specific subdivisions of the MTL in humans. In addition, recent studies suggest that early changes in many neurodegenerative and neuropsychiatric diseases are better detected in smaller subregions of the MTL rather than with whole stru

Quantitative comparison of 21 protocols for labeling hippocampal subfields and parahippocampal subregions in in vivo MRI : towards a harmonized segmentation protocol

OBJECTIVE: An increasing number of human in vivo magnetic resonance imaging (MRI) studies have focused on examining the structure and function of the subfields of the hippocampal formation (the dentate gyrus, CA fields 1-3, and the subiculum) and subregions of the parahippocampal gyrus (entorhinal, perirhinal, and parahippocampal cortices). The ability to interpret the results of such studies and

6-bromoindirubin-3’-oxime promotes osteogenic differentiation of canine BMSCs through inhibition of GSK3β activity and activation of the Wnt/β-catenin signaling pathway

This study aimed to investigate how 6-bromoindirubin-3’-oxime (BIO) increases the osteogenic differentiation of canine bone mesenchymal stem cells (BMSCs) and the role of the Wnt/β-catenin signaling pathway in this process. We mimicked the effect of Wnt by adding BIO to the culture medium of BMSCs and examined whether canonical Wnt signaling positively affects the differentiation of these cells in

Childhood socioeconomic status and childhood maltreatment : Distinct associations with brain structure

The present study examined the relationship between childhood socioeconomic status (SES), childhood maltreatment, and the volumes of the hippocampus and amygdala between the ages of 25 and 36 years. Previous work has linked both low SES and maltreatment with reduced hippocampal volume in childhood, an effect attributed to childhood stress. In 46 adult subjects, only childhood maltreatment, and not

Tryptophan and kynurenine stimulate human decidualization via activating Aryl hydrocarbon receptor : Short title: Kynurenine action on human decidualization

Decidualization is essential for successful pregnancy in rodents and primates. Although L-Tryptophan and its metabolites are essential for mammalian pregnancy, the underlying mechanism is poorly defined. We explored effects of tryptophan and kynurenine on human in vitro decidualization in human endometrial stromal cell line and primary endometrial stromal cells. Tryptophan significantly stimulates

A harmonized segmentation protocol for hippocampal and parahippocampal subregions : Why do we need one and what are the key goals?

The advent of high-resolution magnetic resonance imaging (MRI) has enabled in vivo research in a variety of populations and diseases on the structure and function of hippocampal subfields and subdivisions of the parahippocampal gyrus. Because of the many extant and highly discrepant segmentation protocols, comparing results across studies is difficult. To overcome this barrier, the Hippocampal Sub

Regulation and function of laminin A5 during mouse and human decidualization

Decidualization is essential to the establishment of pregnancy in rodents and primates. Laminin A5 (encoding by Laminin α5) is a member of the laminin family, which is mainly expressed in the basement membranes. Although laminins regulate cellular phenotype maintenance, adhe-sion, migration, growth, and differentiation, the expression, function, and regulation of laminin A5 during early pregnancy

The regulation and function of acetylated high-mobility group box 1 during implantation and decidualization

Introduction: High-mobility group box 1 (HMGB1) is a non-histone nuclear protein and can be extracellularly secreted to induce sterile inflammation. Although uterine deletion of HMGB1 causes implantation and decidualization defects, how secreted HMGB1 is involved in mouse early pregnancy is still unknown. Methods: Mouse models, mouse primary endometrial cells and human endometrial cell lines were

Multi-template analysis of human perirhinal cortex in brain MRI : Explicitly accounting for anatomical variability

RATIONAL: The human perirhinal cortex (PRC) plays critical roles in episodic and semantic memory and visual perception. The PRC consists of Brodmann areas 35 and 36 (BA35, BA36). In Alzheimer's disease (AD), BA35 is the first cortical site affected by neurofibrillary tangle pathology, which is closely linked to neural injury in AD. Large anatomical variability, manifested in the form of different