scholarly journals Morphological Biomarker Differentiating MCI Converters from Nonconverters: Longitudinal Evidence Based on Hemispheric Asymmetry

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Xiaojing Long ◽  
Chunxiang Jiang ◽  
Lijuan Zhang
Keyword(s):  
Medial Temporal Lobe ◽  
Hemispheric Asymmetry ◽  
Morphological Changes ◽  
Brain Regions ◽  
Thickness Measurement ◽  
Morphological Variations ◽  
Asymmetry Analysis ◽  
Potential Index ◽  
Longitudinal Mri ◽  
Magnetic Resonance Imaging Mri

Identifying subjects with mild cognitive impairment (MCI) who may probably progress to Alzheimer’s disease (AD) is important for better understanding the disease mechanisms and facilitating early treatments. In addition to the direct volumetric and thickness measurement based on high-resolution magnetic resonance imaging (MRI), hemispheric asymmetry could be a potential index to detect morphological variations in MCI patients with a high risk of conversion to AD. The present study collected a set of longitudinal MRI data from 53 MCI converters and nonconverters and investigated the asymmetry differences between groups. Asymmetry variation was observed in the medial temporal lobe, especially in the entorhinal cortex, between converters and nonconverters 3 years before the former developed AD. The proposed asymmetry analysis was observed to be sensitive to detect morphological changes between groups as compared to the methods of voxel-based morphometry (VBM) and thickness measurement. Hemispheric asymmetry in specific brain regions as a neuroimaging biomarker can provide helpful information for prediction of MCI conversion.

scholarly journals Neuroinflammatory and morphological changes in late-life depression: the NIMROD study

2016 ◽  
Vol 209 (6) ◽  
pp. 525-526 ◽  
Author(s):  
Li Su ◽  
Yetunde O. Faluyi ◽  
Young T. Hong ◽  
Tim D. Fryer ◽  
Elijah Mak ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Late Life ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Aetiological Factor ◽  
Late Life Depression ◽  
Reactive Protein ◽  
Positron Emission ◽  
Cornu Ammonis ◽  
Magnetic Resonance Imaging Mri

SummaryWe studied neuroinflammation in individuals with late-life, depression, as a risk factor for dementia, using [11C]PK11195 positron emission tomography (PET). Five older participants with major depression and 13 controls underwent PET and multimodal 3T magnetic resonance imaging (MRI), with blood taken to measure C-reactive protein (CRP). We found significantly higher CRP levels in those with late-life depression and raised [11C]PK11195 binding compared with controls in brain regions associated with depression, including subgenual anterior cingulate cortex, and significant hippocampal subfield atrophy in cornu ammonis 1 and subiculum. Our findings suggest neuroinflammation requires further investigation in late-life depression, both as a possible aetiological factor and a potential therapeutic target.

FC07-03 - Neurological soft signs and morphological changes of basal ganglia and thalamus in patients with first-episode psychosis

2011 ◽  
Vol 26 (S2) ◽  
pp. 1848-1848
Author(s):  
D. Hirjak ◽  
B. Stieltjes ◽  
K.H. Fritzsche ◽  
T. Wüstenberg ◽  
U. Seidl ◽  
...  
Keyword(s):  
Basal Ganglia ◽  
Morphological Changes ◽  
Brain Regions ◽  
First Episode Psychosis ◽  
First Episode ◽  
Intracranial Volume ◽  
Neurological Soft Signs ◽  
Episode Psychosis ◽  
Gender Education ◽  
Magnetic Resonance Imaging Mri

ObjectivesMinor motor and sensory deficits or neurological soft signs (NSS) are frequently found in individuals suffering from schizophrenia at any stage of their illness. The basal ganglia and the thalamus are accepted as being important for both motor control and integration of sensory input. However, whether NSS are related to structural alterations of these brain regions remains controversial.Method20 patients with a first-episode psychosis were investigated using high-resolution magnetic resonance imaging (MRI) at 3 Tesla. NSS were examined on the Heidelberg Scale after remission of acute symptoms and correlated with volume and shape of striatum, pallidum and thalamus by using sophisticated MRI analyses, namely VBM-DARTEL (volume) and FSL-FIRST (shape).Results NSS scores in patients with schizophrenia were significantly associated with volumetric changes and surface alterations in all investigated areas. Associations remained significant when controlling for age, gender, education, medication and intracranial volume.ConclusionOur findings lend further support for an involvement of the basal ganglia and the thalamus in NSS.

scholarly journals In vivo synaptic density relates to glucose metabolism at rest in healthy subjects, but is strongly modulated by regional differences

2021 ◽  
pp. 0271678X2098150
Author(s):  
June van Aalst ◽  
Jenny Ceccarini ◽  
Stefan Sunaert ◽  
Patrick Dupont ◽  
Michel Koole ◽  
...  
Keyword(s):  
Glucose Metabolism ◽  
Medial Temporal Lobe ◽  
Regional Differences ◽  
Specific Binding ◽  
Aerobic Glycolysis ◽  
Glucose Consumption ◽  
Brain Regions ◽  
Synaptic Density ◽  
Energy Demands

Preclinical and postmortem studies have suggested that regional synaptic density and glucose consumption (CMRGlc) are strongly related. However, the relation between synaptic density and cerebral glucose metabolism in the human brain has not directly been assessed in vivo. Using [11C]UCB-J binding to synaptic vesicle glycoprotein 2 A (SV2A) as indicator for synaptic density and [18F]FDG for measuring cerebral glucose consumption, we studied twenty healthy female subjects (age 29.6 ± 9.9 yrs) who underwent a single-day dual-tracer protocol (GE Signa PET-MR). Global measures of absolute and relative CMRGlc and specific binding of [11C]UCB-J were indeed highly significantly correlated ( r > 0.47, p < 0.001). However, regional differences in relative [18F]FDG and [11C]UCB-J uptake were observed, with up to 19% higher [11C]UCB-J uptake in the medial temporal lobe (MTL) and up to 17% higher glucose metabolism in frontal and motor-related areas and thalamus. This pattern has a considerable overlap with the brain regions showing different levels of aerobic glycolysis. Regionally varying energy demands of inhibitory and excitatory synapses at rest may also contribute to this difference. Being unaffected by astroglial and/or microglial energy demands, changes in synaptic density in the MTL may therefore be more sensitive to early detection of pathological conditions compared to changes in glucose metabolism.

scholarly journals PET Scan Perfusion Imaging in the Prader–Willi Syndrome: New Insights into the Psychiatric and Social Disturbances

2010 ◽  
Vol 31 (1) ◽  
pp. 275-282 ◽  
Author(s):  
Carine Mantoulan ◽  
Pierre Payoux ◽  
Gwenaëlle Diene ◽  
Mélanie Glattard ◽  
Bernadette Rogé ◽  
...  
Keyword(s):  
Psychiatric Disorders ◽  
Severe Disabilities ◽  
Brain Regions ◽  
Pet Scan ◽  
Prader Willi Syndrome ◽  
Behavioral Skills ◽  
Positron Emission ◽  
Functional Consequences ◽  
Magnetic Resonance Imaging Mri ◽  
Pet Scans

The Prader–Willi syndrome (PWS), a rare multisystem genetic disease, leads to severe disabilities, such as morbid obesity, endocrine dysfunctions, psychiatric disorders, and social disturbances. We explored the whole brain of patients with PWS to detect abnormalities that might explain the behavioral and social disturbances, as well as the psychiatric disorders of these patients. Nine patients with PWS (six males, three females; mean age 16.4 years) underwent a positron emission tomography (PET) scan with H215O as a tracer to measure regional cerebral blood flow (rCBF). The images were compared with those acquired from nine controls (six males, three females; mean age 21.2 years). A morphologic magnetic resonance imaging (MRI) was also performed in PWS patients, and their cognitive and behavioral skills were assessed with Wechsler Intelligence Scale for Children III and the Child Behavior Check List (CBCL). The MRI images showed no evident anatomic abnormalities, whereas PET scans revealed hypoperfused brain regions in PWS patients compared with controls, particularly in the anterior cingulum and superior temporal regions. We observed a significant relationship ( P<0.05) between rCBF in the hypoperfused regions and CBCL scores. The functional consequences of these perfusion abnormalities in specific brain regions might explain the behavioral and social problems observed in these individuals.

APOE ɛ4 Allele Moderates the Association Between Basal Forebrain Nuclei Volumes and Allocentric Navigation in Older Adults Without Dementia

2022 ◽  
pp. 1-17
Author(s):  
Ondrej Lerch ◽  
Martina Pařízková ◽  
Martin Vyhnálek ◽  
Zuzana Nedelská ◽  
Jakub Hort ◽  
...  
Keyword(s):  
Older Adults ◽  
Basal Forebrain ◽  
Medial Temporal Lobe ◽  
Structural Equation ◽  
Brain Aging ◽  
Late Onset ◽  
Brain Regions ◽  
Real Space ◽  
Complex Model ◽  
E4 Allele

Background: Cholinergic deficit and medial temporal lobe (MTL) atrophy are hallmarks of Alzheimer’s disease (AD) leading to early allocentric spatial navigation (aSN) impairment. APOE ɛ4 allele (E4) is a major genetic risk factor for late-onset AD and contributes to cholinergic dysfunction. Basal forebrain (BF) nuclei, the major source of acetylcholine, project into multiple brain regions and, along with MTL and prefrontal cortex (PFC), are involved in aSN processing. Objective: We aimed to determine different contributions of individual BF nuclei atrophy to aSN in E4 positive and E4 negative older adults without dementia and assess whether they operate on aSN through MTL and PFC or independently from these structures. Methods: 120 participants (60 E4 positive, 60 E4 negative) from the Czech Brain Aging Study underwent structural MRI and aSN testing in real-space arena setting. Hippocampal and BF nuclei volumes and entorhinal cortex and PFC thickness were obtained. Associations between brain regions involved in aSN were assessed using MANOVA and complex model of mutual relationships was built using structural equation modelling (SEM). Results: Path analysis based on SEM modeling revealed that BF Ch1-2, Ch4p, and Ch4ai nuclei volumes were indirectly associated with aSN performance through MTL (pch1 - 2 = 0.039; pch4p = 0.042) and PFC (pch4ai = 0.044). In the E4 negative group, aSN was indirectly associated with Ch1-2 nuclei volumes (p = 0.015), while in the E4 positive group, there was indirect effect of Ch4p nucleus (p = 0.035). Conclusion: Our findings suggest that in older adults without dementia, BF nuclei affect aSN processing indirectly, through MTL and PFC, and that APOE E4 moderates these associations.

scholarly journals The Influence of Salt Solution on Morphological Changes in a Geosynthetic Clay Liner

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Mochamad Arief Budihardjo
Keyword(s):  
Salt Solution ◽  
Morphological Changes ◽  
Microscopic Analysis ◽  
Optical Microscope ◽  
Distilled Water ◽  
Nacl Solution ◽  
Geosynthetic Clay Liner ◽  
Clay Liner ◽  
Morphological Variations ◽  
Crystal Deposit

Morphological variations of geosynthetic clay liner (GCL) samples, hydrated with two different permeates, distilled water and NaCl solution (100 mM concentration), were observed in detail using microscopic analysis. After the GCL samples were hydrated with the NaCl solution, they were observed with an optical microscope. While the surface of the treated GCL samples was similar to the surface of the untreated GCL, a crystal deposit was found on the surface of the treated samples. Using a scanning electron microscope (SEM), a more solid appearance was observed for the bentonite particles contained in the GCL after the sample was hydrated with distilled water in comparison to the GCL sample that was hydrated with the NaCl solution. It appears that salt solution hydration results in less swelling of the bentonite particles. Furthermore, the energy-dispersive X-ray spectrometer (EDS) results showed that distilled water hydration had no effect on the distribution of the elements contained in the GCL samples. However, bound chlorine was observed, which demonstrated that the bentonite particles had absorbed the NaCl solution. In addition, changes in the hydraulic conductivity of the hydrated GCL samples were also observed.

scholarly journals Dynamical consequences of regional heterogeneity in the brain’s transcriptional landscape

2020 ◽  
Author(s):  
Gustavo Deco ◽  
Kevin Aquino ◽  
Aurina Arnatkevičiūtė ◽  
Stuart Oldham ◽  
Kristina Sabaroedin ◽  
...  
Keyword(s):  
Gene Expression ◽  
Large Scale ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Global Gene Expression ◽  
Brain Regions ◽  
Biophysical Model ◽  
Neuronal Dynamics ◽  
Regional Heterogeneity ◽  
Magnetic Resonance Imaging Mri

AbstractBrain regions vary in their molecular and cellular composition, but how this heterogeneity shapes neuronal dynamics is unclear. Here, we investigate the dynamical consequences of regional heterogeneity using a biophysical model of whole-brain functional magnetic resonance imaging (MRI) dynamics in humans. We show that models in which transcriptional variations in excitatory and inhibitory receptor (E:I) gene expression constrain regional heterogeneity more accurately reproduce the spatiotemporal structure of empirical functional connectivity estimates than do models constrained by global gene expression profiles and MRI-derived estimates of myeloarchitecture. We further show that regional heterogeneity is essential for yielding both ignition-like dynamics, which are thought to support conscious processing, and a wide variance of regional activity timescales, which supports a broad dynamical range. We thus identify a key role for E:I heterogeneity in generating complex neuronal dynamics and demonstrate the viability of using transcriptional data to constrain models of large-scale brain function.

scholarly journals Taste quality representation in the human brain

2019 ◽  
Author(s):  
Jason A. Avery ◽  
Alexander G. Liu ◽  
John E. Ingeholm ◽  
Cameron D. Riddell ◽  
Stephen J. Gotts ◽  
...  
Keyword(s):  
Human Brain ◽  
Cortical Neurons ◽  
Brain Regions ◽  
Taste Quality ◽  
7 Tesla ◽  
Mammalian Brain ◽  
High Magnetic Field Strength ◽  
Magnetic Resonance Imaging Mri ◽  
Spatial Locations ◽  
Univariate Analyses

SUMMARYIn the mammalian brain, the insula is the primary cortical substrate involved in the perception of taste. Recent imaging studies in rodents have identified a gustotopic organization in the insula, whereby distinct insula regions are selectively responsive to one of the five basic tastes. However, numerous studies in monkeys have reported that gustatory cortical neurons are broadly-tuned to multiple tastes, and tastes are not represented in discrete spatial locations. Neuroimaging studies in humans have thus far been unable to discern between these two models, though this may be due to the relatively low spatial resolution employed in taste studies to date. In the present study, we examined the spatial representation of taste within the human brain using ultra-high resolution functional magnetic resonance imaging (MRI) at high magnetic field strength (7-Tesla). During scanning, participants tasted sweet, salty, sour and tasteless liquids, delivered via a custom-built MRI-compatible tastant-delivery system. Our univariate analyses revealed that all tastes (vs. tasteless) activated primary taste cortex within the bilateral dorsal mid-insula, but no brain region exhibited a consistent preference for any individual taste. However, our multivariate searchlight analyses were able to reliably decode the identity of distinct tastes within those mid-insula regions, as well as brain regions involved in affect and reward, such as the striatum, orbitofrontal cortex, and amygdala. These results suggest that taste quality is not represented topographically, but by a combinatorial spatial code, both within primary taste cortex as well as regions involved in processing the hedonic and aversive properties of taste.

scholarly journals Spatial inhibition of return is impaired in mild cognitive impairment and mild Alzheimer’s disease

2020 ◽  
Author(s):  
Xiong Jiang ◽  
James H. Howard ◽  
G. Wiliam Rebeck ◽  
R. Scott Turner
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Medial Temporal Lobe ◽  
Inhibition Of Return ◽  
Memory Performance ◽  
Brain Regions ◽  
List Type ◽  
Older Individuals

ABSTRACTSpatial inhibition of return (IOR) refers to the phenomenon by which individuals are slower to respond to stimuli appearing at a previously cued location compared to un-cued locations. Here we provide evidence supporting that spatial IOR is mildly impaired in individuals with mild cognitive impairment (MCI) or mild Alzheimer’s disease (AD), and the impairment is readily detectable using a novel double cue paradigm. Furthermore, reduced spatial IOR in high-risk healthy older individuals is associated with reduced memory and other neurocognitive task performance, suggesting that the novel double cue spatial IOR paradigm may be useful in detecting MCI and early AD.SIGNIFICANCE STATEMENTNovel double cue spatial inhibition of return (IOR) paradigm revealed a robust effect IOR deficits in individuals with mild cognitive impairment (MCI) or mild Alzheimer’s disease (AD)Spatial IOR effect correlates with memory performance in healthy older adults at a elevated risk of Alzheimer’s disease (with a family history or APOE e4 allele)The data suggests that double cue spatial IOR may be sensitive to detect early AD pathological changes, which may be linked to disease progress at the posterior brain regions (rather than the medial temporal lobe)

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