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Background: Clinical trial findings on cholinesterase inhibitors (ChEIs) for mild cognitive impairment (MCI) are inconclusive, offering limited support for their MCI treatment. Given that nearly half of amnestic MCI cases lack cerebral amyloid-β (Aβ) deposition, a hallmark of Alzheimer's disease; this Aβ heterogeneity may explain inconsistent results. Objective: This study aimed to assess whether Aβ deposition moderates ChEI effects on amnestic MCI cognition. Methods: We examined 118 individuals with amnestic MCI (ages 55–90) in a longitudinal cohort study. Baseline and 2-year follow-up assessments included clinical evaluations, neuropsychological testing, and multimodal neuroimaging. Generalized linear models were primarily analyzed to test amyloid positivity's moderation of ChEI effects on cognitive change over 2 years. Cognitive outcomes included Mini-Mental Status Examination score, the total score of the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery, and Clinical Dementia Rating-sum of boxes. Results: The analysis found no significant ChEI use x amyloid positivity interaction for all cognitive outcomes. ChEI use, irrespective of Aβ status, was associated with more cognitive decline over the 2-year period. Conclusions: Aβ pathology does not appear to moderate ChEI effects on cognitive decline in MCI. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have demonstrated an association between altered liver function and Alzheimer's disease (AD) or related dementia. Nevertheless, the neuropathological substrates underlying the association remains unclear. Our aim was to investigate the association between liver function markers and the longitudinal changes of in vivo AD pathologies. Methods: We utilized a longitudinal study designs using data from the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's Disease, an ongoing prospective cohort study that began in 2014. Total 347 older adults between 55 and 90 years of age assessed at both baseline and 2‐year follow‐up were included in community and memory clinic setting. We used four liver function markers (alanine aminotransferase [ALT], aspartate aminotransferase [AST], AST to ALT ratio, and total bilirubin) as exposure variables. Participants underwent comprehensive clinical assessments and multimodal brain imaging, including Pittsburgh compound‐B positron emission tomography (PET), AV‐1451 PET, fluorodeoxyglucose (FDG)‐PET, and MRI at both baseline and the 2‐year follow‐up. Results: A higher ALT level and lower AST to ALT ratio at baseline were associated with greater amyloid deposition over a 2‐year period (ALT: β, 0.151 [95% CI, 0.007 to 0.033], P = 0.004; AST to ALT ratio: β, ‐0.153 [95% CI, ‐0.050 to ‐0.010], P = 0.004), but not with the change of other neuroimaging markers. A lower total bilirubin level was associated with greater tau deposition over a 2‐year period (β, ‐0.442 [95% CI, ‐0.385 to ‐0.106], P < 0.001), but not with the change of other neuroimaging markers. In contrast, AST alone was not associated with any neuroimaging marker change. Conclusions: The present findings, based on longitudinal observation for older adults, suggest that lower liver function may accelerate the accumulation of AD pathology in the brain. These results also support the possibility that the liver‐brain axis could be a potential target for therapeutic or preventive strategies against AD. [ABSTRACT FROM AUTHOR]

A 45-yr-old female patient was admitted with one-month history of headache and progressive left hemiparesis. Brain magnetic resonance imaging (MRI) demonstrated a mass lesion in her right frontal lobe. Her brain tumor was confirmed as a small cell glioblastoma. Her follow-up brain MRI, taken at 8 months after her initial surgery demonstrated tumor recurrence in the right frontal lobe. Contrast-enhanced 7.0T brain magnetic resonance imaging (MRI) was safely performed before surgery and at the time of recurrence. Compared with 1.5T and 3.0T brain MRI, 7.0T MRI showed sharpened images of the brain tumor contexture with detailed anatomical information. The fused images of 7.0T and 1.5T brain MRI taken at the time of recurrence demonstrated no significant discrepancy in the positions of the anterior and the posterior commissures. It is suggested that 7.0T MRI can be safely utilized for better images of the maligant gliomas before and after surgery.

Background: Altered thyroid hormone levels have been associated with increased risk of Alzheimer's disease (AD) dementia and related cognitive decline. However, the neuropathological substrates underlying the link between thyroid hormones and AD dementia are not yet fully understood. We first investigated the association between serum thyroid hormone levels and in vivo AD pathologies including both beta-amyloid (Aβ) and tau deposition measured by positron emission tomography (PET). Given the well-known relationship between Aβ and tau pathology in AD, we additionally examined the moderating effects of thyroid hormone levels on the association between Aβ and tau deposition. Methods: This cross-sectional study was conducted as part of the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's Disease (KBASE) cohort. This study included a total of 291 cognitively normal adults aged 55 to 90. All participants received comprehensive clinical assessments, measurements for serum total triiodothyronine (T3), free triiodothyronine (fT3), free thyroxine (fT4), and thyroid-stimulating hormone (TSH), and brain imaging evaluations including [11C]-Pittsburgh compound B (PiB)- PET and [18F] AV-1451 PET. Results: No associations were found between either thyroid hormones or TSH and Aβ and tau deposition on PET. However, fT4 (p = 0.002) and fT3 (p = 0.001) exhibited significant interactions with Aβ on tau deposition: The sensitivity analyses conducted after the removal of an outlier showed that the interaction effect between fT4 and Aβ deposition was not significant, whereas the interaction between fT3 and Aβ deposition remained significant. However, further subgroup analyses demonstrated a more pronounced positive relationship between Aβ and tau in both the higher fT4 and fT3 groups compared to the lower group, irrespective of outlier removal. Meanwhile, neither T3 nor TSH had any interaction with Aβ on tau deposition. Conclusion: Our findings suggest that serum thyroid hormones may moderate the relationship between cerebral Aβ and tau pathology. Higher levels of serum thyroid hormones could potentially accelerate the Aβ-dependent tau deposition in the brain. Further replication studies in independent samples are needed to verify the current results. [ABSTRACT FROM AUTHOR]

Background: Growing evidence suggests that not only cerebrovascular disease but also Alzheimer’s disease (AD) pathological process itself cause cerebral white matter degeneration, resulting in white matter hyperintensities (WMHs). Some preclinical evidence also indicates that white matter degeneration may precede or affect the development of AD pathology. This study aimed to clarify the direction of influence between in vivo AD pathologies, particularly beta-amyloid (Aβ) and tau deposition, and WMHs through longitudinal approach. Methods: Total 282 older adults including cognitively normal and cognitively impaired individuals were recruited from the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer’s Disease (KBASE) cohort. The participants underwent comprehensive clinical and neuropsychological assessment, [11C] Pittsburgh Compound B PET for measuring Aβ deposition, [18F] AV-1451 PET for measuring tau deposition, and MRI scans with fluid-attenuated inversion recovery image for measuring WMH volume. The relationships between Aβ or tau deposition and WMH volume were examined using multiple linear regression analysis. In this analysis, baseline Aβ or tau were used as independent variables, and change of WMH volume over 2 years was used as dependent variable to examine the effect of AD pathology on increase of WMH volume. Additionally, we set baseline WMH volume as independent variable and longitudinal change of Aβ or tau deposition for 2 years as dependent variables to investigate whether WMH volume could precede AD pathologies. Results: Baseline Aβ deposition, but not tau deposition, had significant positive association with longitudinal change of WMH volume over 2 years. Baseline WMH volume was not related with any of longitudinal change of Aβ or tau deposition for 2 years. We also found a significant interaction effect between baseline Aβ deposition and sex on longitudinal change of WMH volume. Subsequent subgroup analyses showed that high baseline Aβ deposition was associated with increase of WMH volume over 2 years in female, but not in male. Conclusions: Our findings suggest that Aβ deposition accelerates cerebral WMHs, particularly in female, whereas white matter degeneration appears not influence on longitudinal Aβ increase. The results also did not support any direction of influence between tau deposition and WMHs. [ABSTRACT FROM AUTHOR]