• Title/Summary/Keyword: amyloid

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Analysis of Correlations among β-amyloid, Serum Lipid Levels, and Cognitive Function in the Elderly with Mild Alzheimer's Dementia (경증 알츠하이머 치매노인에서 베타 아밀로이드 및 혈중 지질 수준과 인지기능과의 상관관계 분석)

  • Nam, Seung-Min;Lee, Do-Youn
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.11
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    • pp.115-120
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    • 2019
  • This study was undertaken to determine the correlation between β-amyloid, serum lipid levels, and cognitive function in the elderly with mild Alzheimer's dementia. The study was conducted in December 2018, enrolling 45 elderly people with mild Alzheimer's disease. Blood analysis measured the β-amyloid and serum lipid levels, and cognitive function was measured using MMSE-K. The correlation between β-amyloid, serum lipid levels and cognitive function was determined using Pearson's correlation analysis. A significantly negative correlation was observed between the β-amyloid level and cognitive function (p<0.05). Furthermore, serum lipid levels and cognitive function also revealed a significantly negative correlation between TC and LDL levels (p<0.05). These results indicate that increasing levels of β-amyloid, TC, and LDL augments a negative correlation that decreases the cognitive function, signifying that management of pathologic factors related to dementia is important for the prevention and improvement of cognitive function in dementia patients.

Control of Morphology and Subsequent Toxicity of AβAmyloid Fibrils through the Dequalinium-induced Seed Modification

  • Kim, Jin-A;Myung, Eun-Kyung;Lee, In-Hwan;Paik, Seung-R.
    • Bulletin of the Korean Chemical Society
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    • v.28 no.12
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    • pp.2283-2287
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    • 2007
  • Amyloid fibril formation of amyloid β/A4 protein (Aβ) is critical to understand the pathological mechanism of Alzheimer's disease and develop controlling strategy toward the neurodegenerative disease. For this purpose, dequalinium (DQ) has been employed as a specific modifier for Aβ aggregation and its subsequent cytotoxicity. In the presence of DQ, the final thioflavin-T binding fluorescence of Aβ aggregates decreased significantly. It was the altered morphology of Aβ aggregates in a form of the bundles of the fibrils, distinctive from normal single-stranded amyloid fibrils, and the resulting reduced β-sheet content that were responsible for the decreased fluorescence. The morphological transition of Aβ aggregates assessed with atomic force microscope indicated that the bundle structure observed with DQ appeared to be resulted from the initial multimeric seed structure rather than lateral association of preformed single-stranded fibrils. Investigation of the seeding effect of the DQ-induced Aβ aggregates clearly demonstrated that the seed structure has determined the final morphology of Aβ aggregates as well as the aggregative kinetics by shortening the lag phase. In addition, the cytotoxicity was also varied depending on the final morphology of the aggregates. Taken together, DQ has been considered to be a useful chemical probe to control the cytotoxicity of the amyloid fibrils by influencing the seed structures which turned out to be central to develop therapeutic strategy by inducing the amyloid fibrils in different shapes with varied toxicities.

Effects of Dual-Task Training with Cognitive Tasks on Cognitive Function and β-amyloid Levels in the Elderly with Mild Dementia

  • Lee, Do-Youn;Nam, Seung-Min
    • Journal of the Korean Society of Physical Medicine
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    • v.15 no.2
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    • pp.23-30
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    • 2020
  • PURPOSE: The purpose of this study was to examine the effects of dual-task training with cognitive tasks on cognitive functions and β-amyloid levels in the elderly with mild dementia. METHODS: The subjects were 36 elderly inpatients diagnosed with mild dementia at S Hospital located in Gyeongsangbuk-do, South Korea. The patients were randomly divided into a dual-task training group (DTG; n = 18) or a single-task training group (STG; n = 18). DTG performed dual-task training with cognitive tasks while STG performed only exercise tasks. These groups performed their respective exercises during a 30-minute session occurring three times a week over an 8-week period. MMSE-K and GDS were used to measure the subjects' cognitive function. To assess the subjects' dementia-related factors, their β-amyloid levels were measured by blood analysis. RESULTS: The results of the experiment were as follows: DTG showed statistically significant differences between their MMSE-K scores and β-amyloid levels before and after training (p < .05), whereas they exhibited no statistically significant differences in their GDS scores. MMSE-K scores and β-amyloid levels were significantly different between DTG and STG after training. CONCLUSION: The present study's overall results indicate that dual-task training with cognitive tasks is more effective than single-task training in improving cognitive functions and β-amyloid levels in the elderly with mild dementia. In other words, regular dual-task training can be considered as effective in improving cognitive function and dementia-related factors in the elderly with mild dementia and thus may be suggested as an effective exercise method for the treatment and early prevention of dementia.

Synthesis and Evaluation of Oleanolic Acid-Conjugated Lactoferrin for β-Amyloid Plaque Imaging

  • Kim, Sung-Min;Kim, Dongkyu;Chae, Min Kyung;Jeong, Il-Ha;Cho, Jee-Hyun;Choi, Naeun;Lee, Kyo Chul;Lee, Chulhyun;Ryu, Eun Kyoung
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3671-3675
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    • 2012
  • ${\beta}$-Amyloid accumulation in the brain is a pathological hallmark of Alzheimer's disease (AD). Since early detection of ${\beta}$-amyloid may facilitate more successful and timely therapeutic interventions, many investigators have focused on developing AD diagnostic reagents that can penetrate the blood-brain barrier (BBB). Oleanolic acid (OA) is a substance found in a variety of plants that has been reported to prevent the progression of AD in mice. In this study, we synthesized and evaluated a new radioligand in which OA was conjugated to lactoferrin (Lf, an iron-binding glycoprotein that crosses the BBB) for the diagnosis of AD. In an in vitro study in which OA-Lf was incubated with ${\beta}$-amyloid (1-42) aggregates for 24 h, we found that OA-Lf effectively inhibited ${\beta}$-amyloid aggregation and fibril formation. In vivo studies demonstrated that $^{123}I$-OA-Lf brain uptake was higher than$^{123}I$-Lf uptake. Therefore, radiolabeled OA-Lf may have diagnostic potential for ${\beta}$-amyloid imaging.

Vaccinium uliginosum L. Improves Amyloid β Protein-Induced Learning and Memory Impairment in Alzheimer's Disease in Mice

  • Choi, Yoon-Hee;Kwon, Hyuck-Se;Shin, Se-Gye;Chung, Cha-Kwon
    • Preventive Nutrition and Food Science
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    • v.19 no.4
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    • pp.343-347
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    • 2014
  • The present study investigated the effects of Vaccinium uliginosum L. (bilberry) on the learning and memory impairments induced by amyloid-${\beta}$ protein ($A{\beta}P$) 1-42. ICR Swiss mice were divided into 4 groups: the control ($A{\beta}40$-1A), control with 5% bilberry group ($A{\beta}40$-1B), amyloid ${\beta}$ protein 1-42 treated group ($A{\beta}1$-42A), and $A{\beta}1$-42 with 5% bilberry group ($A{\beta}1$-42B). The control was treated with amyloid ${\beta}$-protein 40-1 for placebo effect, and Alzheimer's disease (AD) group was treated with amyloid ${\beta}$-protein 1-42. Amyloid ${\beta}$-protein 1-42 was intracerebroventricular (ICV) micro injected into the hippocampus in 35% acetonitrile and 0.1% trifluoroacetic acid. Although bilberry added groups tended to decrease the finding time of hidden platform, no statistical significance was found. On the other hand, escape latencies of $A{\beta}P$ injected mice were extended compared to that of $A{\beta}40$-1. In the Probe test, bilberry added $A{\beta}1$-42B group showed a significant (P<0.05) increase of probe crossing frequency compared to $A{\beta}1$-42A. Administration of amyloid protein ($A{\beta}1$-42) decreased working memory compared to $A{\beta}40$-1 control group. In passive avoidance test, bilberry significantly (P<0.05) increased the time of staying in the lighted area compared to AD control. The results suggest that bilberry may help to improve memory and learning capability in chemically induced Alzheimer's disease in experimental animal models.

Classification of Aβ State From Brain Amyloid PET Images Using Machine Learning Algorithm

  • Chanda Simfukwe;Reeree Lee;Young Chul Youn;Alzheimer’s Disease and Related Dementias in Zambia (ADDIZ) Group
    • Dementia and Neurocognitive Disorders
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    • v.22 no.2
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    • pp.61-68
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    • 2023
  • Background and Purpose: Analyzing brain amyloid positron emission tomography (PET) images to access the occurrence of β-amyloid (Aβ) deposition in Alzheimer's patients requires much time and effort from physicians, while the variation of each interpreter may differ. For these reasons, a machine learning model was developed using a convolutional neural network (CNN) as an objective decision to classify the Aβ positive and Aβ negative status from brain amyloid PET images. Methods: A total of 7,344 PET images of 144 subjects were used in this study. The 18F-florbetaben PET was administered to all participants, and the criteria for differentiating Aβ positive and Aβ negative state was based on brain amyloid plaque load score (BAPL) that depended on the visual assessment of PET images by the physicians. We applied the CNN algorithm trained in batches of 51 PET images per subject directory from 2 classes: Aβ positive and Aβ negative states, based on the BAPL scores. Results: The binary classification of the model average performance matrices was evaluated after 40 epochs of three trials based on test datasets. The model accuracy for classifying Aβ positivity and Aβ negativity was (95.00±0.02) in the test dataset. The sensitivity and specificity were (96.00±0.02) and (94.00±0.02), respectively, with an area under the curve of (87.00±0.03). Conclusions: Based on this study, the designed CNN model has the potential to be used clinically to screen amyloid PET images.

Fine Needle Aspiration Cytology of Amyloid Goiter - A Case Report - (아밀로이드 갑상선종대의 세침흡인 세포학적 소견 - 1예 보고 -)

  • Chae, Seoung-Wan;Nam, Eun-Sook;Kim, Duck-Hwan;Shin, Hyung-Sik;Sohn, Jin-Hee
    • The Korean Journal of Cytopathology
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    • v.11 no.2
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    • pp.109-114
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    • 2000
  • Amyloid golfer is a rare disease entity that is defined as a symptomatic mass or clinically detectable thyroid enlargement because of amyloid deposition. We present a case of amyloid golfer diagnosed in the fine needle aspiration cytology(FNAC) in a 73-year-old Korean woman presented with nephrotic syndrome and thyroid enlargement. The thyroid function was in normal range. Thyroid scan showed a nodule, $4{\time}2cm$ in the right lobe with underlying diffuse golfer. Aspirates revealed benign looking follicular cells and scattered eosinophilic material. The sections of the cell block showed nodular deposit of eosinophilic hyalinized material in the interfollicular area. It showed apple-green birefringence under polarization with Congo red stain. The renal biopsy also exhibited deposition of eosinophilic materials in the glomeruli and interstitial vascular wall, which were confirmed as amyloidosis. This material was morphologically distinct from the colloid.

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Mercury induced the Accumulation of Amyloid Beta (Aβ) in PC12 Cells: The Role of Production and Degradation of Aβ

  • Song, Ji-Won;Choi, Byung-Sun
    • Toxicological Research
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    • v.29 no.4
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    • pp.235-240
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    • 2013
  • Extracellular accumulation of amyloid beta protein ($A{\beta}$) plays a central role in Alzheimer's disease (AD). Some metals, such as copper, lead, and aluminum can affect the $A{\beta}$ accumulation in the brain. However, the effect of mercury on $A{\beta}$ accumulation in the brain is not clear. Thus, this study was proposed to estimate whether mercury concentration affects $A{\beta}$ accumulation in PC12 cells. We treated 10, 100, and 1000 nM $HgCl_2$ (Hg) or $CH_3HgCl_2$ (MeHg) for 48 hr in PC12 cells. After treatment, $A{\beta}_{40}$ in culture medium increased in a dose- and time-dependent manner. Hg and MeHg increased amyloid precursor protein (APP), which is related to $A{\beta}$ production. Neprilysin (NEP) levels in PC12 cells were decreased by Hg and MeHg treatment. These results suggested that Hg induced $A{\beta}$ accumulation through APP overproduction and reduction of NEP.

Amyloid-producing Odontogenic Tumor in Two Dogs (개에서 아밀로이드 생산 치원성종양 2예)

  • Kim, Hyung-Jin;Kang, Min-Soo;Oh, Won-Seok;Kim, Eun-Ok;Lee, Woo-Yeal;Kim, Eun-Young;Kim, Dae-Yong
    • Journal of Veterinary Clinics
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    • v.26 no.3
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    • pp.279-281
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    • 2009
  • Amyloid-producing odontogenic tumors were described in the gingival masses of two Maltese dogs. Gingival masses were surgically removed and submitted for diagnosis. On histopathology, the masses were poorly demarcated, infiltrative, and consisted of cuboidal and columnar epithelial cells with palisading pattern. Nodular deposit of congophilic amyloid-like material and mineralization were another features of the tumors. Immunohistochemically, the neoplasticd cells were positive to pancytokeratin and neuron-specific enolase but were negative to vimentin. The amorphous homogeneous eosinophilic materials were positive to Congo red stain and showed apple-green color under the polarized microscope. Based on these results, both cases were diagnosed as amyloid-producing odontogenic tumors in dogs.