| 1. |
- Larsson, Susanna C., et al.
(författare)
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Does Treating Vascular Risk Factors Prevent Dementia and Alzheimer's Disease? A Systematic Review and Meta-Analysis.
- 2018
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Ingår i: Journal of Alzheimer's Disease. - Stockholm : Karolinska Institutet, Institute of Environmental Medicine. - 1387-2877 .- 1875-8908. ; 64:2, s. 657-668
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Epidemiological evidence has associated Alzheimer's disease (AD) with vascular risk factors (VRFs), but whether treatment of VRFs reduces the incidence of dementia and AD is uncertain.OBJECTIVE: To conduct a systematic review and meta-analysis to summarize available data on the impact of treatment of VRFs on dementia and AD incidence.METHODS: Pertinent studies published until 1 January 2018 were identified from PubMed. Both randomized controlled trials (RCT) and prospective studies that investigated the impact of treatment of VRFs on dementia or AD incidence were included.RESULTS: Eight RCTs and 52 prospective studies were identified. Antihypertensive treatment was associated with a non-significant reduced risk of dementia in RCTs (n = 5; relative risk [RR], 0.84; 95% confidence interval [CI], 0.69-1.02) and prospective studies (n = 3; RR, 0.77; 95% CI, 0.58-1.01) and with reduced AD risk in prospective studies (n = 5; RR = 0.78; 95% CI, 0.66-0.91). In prospective studies, treatment of hyperlipidemia with statins, but not nonstatin lipid-lowering agents, was associated with reduced risk of dementia (n = 17; RR, 0.77; 95% CI, 0.63-0.95) and AD (n = 13; RR, 0.86; 95% CI, 0.80-0.92). The single RCT on statins and dementia incidence showed no association. Data from one RCT and six prospective studies did not support a beneficial impact of antidiabetic drugs or insulin therapy on dementia risk.CONCLUSION: Current evidence indicates that antihypertensives and statins might reduce the incidence of dementia and AD. Further trials to determine the effect of VRF on AD are needed.
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| 2. |
- Aho, Leena, et al.
(författare)
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Immunohistochemical Visualization of Amyloid-β Protein Precursor and Amyloid-β in Extra- and Intracellular Compartments in the Human Brain
- 2010
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Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 20:4, s. 1015-1028
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Tidskriftsartikel (refereegranskat)abstract
- Amyloid-beta (Abeta) peptide, a cleavage product of the amyloid-beta protein precursor (AbetaPP), has been reported to be detected in the intracellular compartment. Most studies reporting the presence of intracellular Abeta are based on the use of immunohistochemistry. In this study, the presence of AbetaPP and Abeta was assessed by applying immunohistochemistry in postmortem human brain tissue samples obtained from 10 neurologically intact subjects, the youngest being 2 years of age, one aged with mild cognitive impairment, 14 neurologically diseased, and in one brain biopsy sample obtained from a subject with normal pressure hydrocephalus. Intracellular immunoreactivity was detected in all ages independent of the disease state or existence of extracellular Abeta aggregates with all antibodies directed to AbetaPP, with three Abeta antibodies (4G8, 6E10, and 82E1), clones that are unable to distinguish Abeta from AbetaPP. These results suggest that it is AbetaPP rather than Abeta that is detected intracellularly when using the antibodies listed above. Furthermore, the staining results varied when different pretreatment strategies were applied. Interestingly intracellular Abeta was detected with antibodies directed to the C-terminus of Abeta (neoepitope) in subjects with Alzheimer's disease. The lack of intracellular immunoreactivity in unimpaired subjects, when using antibodies against neoepitopes, may be due to a lack or a low level of the protein that is thus undetectable at light microscopic level by immunohistochemistry method. The staining results and conclusions depended strongly on the chosen antibody and the pretreatment strategy and thus multiple antibodies must be used when assessing the intracellular accumulation of Abeta.
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| 3. |
- Al-Hammadi, Mustafa, 1995-, et al.
(författare)
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Machine Learning Approaches for Dementia Detection Through Speech and Gait Analysis : A Systematic Literature Review
- 2024
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 100:1, s. 1-27
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Forskningsöversikt (refereegranskat)abstract
- Background:Dementia is a general term for several progressive neurodegenerative disorders including Alzheimer’s disease. Timely and accurate detection is crucial for early intervention. Advancements in artificial intelligence present significant potential for using machine learning to aid in early detection.Objective:Summarize the state-of-the-art machine learning-based approaches for dementia prediction, focusing on non-invasive methods, as the burden on the patients is lower. Specifically, the analysis of gait and speech performance can offer insights into cognitive health through clinically cost-effective screening methods.Methods:A systematic literature review was conducted following the PRISMA protocol (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The search was performed on three electronic databases (Scopus, Web of Science, and PubMed) to identify the relevant studies published between 2017 to 2022. A total of 40 papers were selected for review.Results:The most common machine learning methods employed were support vector machine followed by deep learning. Studies suggested the use of multimodal approaches as they can provide comprehensive and better prediction performance. Deep learning application in gait studies is still in the early stages as few studies have applied it. Moreover, including features of whole body movement contribute to better classification accuracy. Regarding speech studies, the combination of different parameters (acoustic, linguistic, cognitive testing) produced better results.Conclusions:The review highlights the potential of machine learning, particularly non-invasive approaches, in the early prediction of dementia. The comparable prediction accuracies of manual and automatic speech analysis indicate an imminent fully automated approach for dementia detection.
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| 4. |
- Alafuzoff, Irina
(författare)
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Alzheimer's disease-related lesions
- 2013
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Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 33:Suppl 1, s. S173-S179
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Forskningsöversikt (refereegranskat)abstract
- The invitation to contribute to "Alzheimer's Disease: Advances for a New Century" gave me an opportunity to briefly summarize my personal opinions about how the field of neuropathology has evolved. The goal is to briefly exemplify the changes that have influenced the way we conduct our diagnostic work as well as the way we interpret our results. From an era of histological stains, we have moved to visualization of altered proteins in predicted brain regions; we have also realized that in many aged subjects, not one but a plethora of co-pathologies are seen, and finally, we have become aware that the degenerative process is initiated much earlier than we ever suspected.
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| 5. |
- Alafuzoff, Irina, et al.
(författare)
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Mixed Brain Pathology Is the Most Common Cause of Cognitive Impairment in the Elderly
- 2020
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Ingår i: Journal of Alzheimer's Disease. - : IOS PRESS. - 1387-2877 .- 1875-8908. ; 78:1, s. 453-465
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Tidskriftsartikel (refereegranskat)abstract
- Background: Systemic diseases, diabetes mellitus (DM), and cardiovascular disease (CaVD) have been suggested being risk factors for cognitive impairment (CI) and/or influence Alzheimer's disease neuropathologic change (ADNC).Objective: The purpose was to assess the type and the extent of neuropathological alterations in the brain and to assess whether brain pathology was associated with CaVD or DM related alterations in peripheral organs, i.e., vessels, heart, and kidney.Methods: 119 subjects, 15% with DM and 24% with CI, age range 80 to 89 years, were chosen and neuropathological alterations were assessed applying immunohistochemistry.Results: Hyperphosphorylated tau (HP tau) was seen in 99%, amyloid-beta (A beta) in 71%, transactive DNA binding protein 43 (TDP43) in 62%, and alpha-synuclein (alpha S) in 21% of the subjects. Primary age related tauopathy was diagnosed in 29% (more common in females), limbic predominant age-related TDP encephalopathy in 4% (14% of subjects with CI), and dementia with Lewy bodies in 3% (14% of subjects with CI) of the subjects. High/intermediate level of ADNC was seen in 47% and the extent of HPt increased with age. The extent of ADNC was not associated with the extent of pathology observed in peripheral organs, i.e., DM or CaVD. Contrary, brain alterations such as pTDP43 and cerebrovascular lesions (CeVL) were influenced by DM, and CeVL correlated significantly with the extent of vessel pathology.Conclusion: In most (66%) subjects with CI, the cause of impairment was "mixed pathology", i.e., ADNC combined with TDP43, alpha S, or vascular brain lesions. Furthermore, our results suggest that systemic diseases, DMand CaVD, are risk factors for CI but not related to ADNC.
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| 6. |
- Boström, Gustaf, et al.
(författare)
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Different Inflammatory Signatures in Alzheimer's Disease and Frontotemporal Dementia Cerebrospinal Fluid
- 2021
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 81:2, s. 629-640
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Tidskriftsartikel (refereegranskat)abstract
- Background: Neuroinflammatory processes are common in neurodegenerative diseases such as Alzheimer's disease (AD) and frontotemporal dementia (FTD), but current knowledge is limited as to whether cerebrospinal fluid (CSF) levels of neuroinflammatory proteins are altered in these diseases.Objective: To identify and characterize neuroinflammatory signatures in CSF from patients with AD, mild cognitive impairment (MCI), and FTD.Methods: We used proximity extension assay and ANOVA to measure and compare levels of 92 inflammatory proteins in CSF from 42 patients with AD, 29 with MCI due to AD (MCI/AD), 22 with stable MCI, 42 with FTD, and 49 control subjects, correcting for age, gender, collection unit, and multiple testing.Results: Levels of matrix metalloproteinase-10 (MMP-10) were increased in AD, MCI/AD, and FTD compared with controls (AD: fold change [FC] = 1.32, 95% confidence interval [CI] 1.14-1.53, q = 0.018; MCI/AD: FC = 1.53, 95% CI 1.20-1.94, q = 0.045; and FTD: FC = 1.42, 95% CI 1.10-1.83, q = 0.020). MMP-10 and eleven additional proteins were increased in MCI/AD, compared with MCI (q < 0.05). In FTD, 36 proteins were decreased, while none was decreased in AD or MCI/AD, compared with controls (q < 0.05).Conclusion: In this cross-sectional multi-center study, we found distinct patterns of CSF inflammatory marker levels in FTD and in both early and established AD, suggesting differing neuroinflammatory processes in the two disorders.
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| 7. |
- Choo, Il Han, et al.
(författare)
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Combination of f 18 fdg pet and cerebrospinal fluid biomarkers as a better predictor of the progression to alzheimer's disease in mild cognitive impairment patients
- 2013
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Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 33:4, s. 929-939
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Tidskriftsartikel (refereegranskat)abstract
- The biomarker-based new diagnostic criteria have been proposed for Alzheimer's disease (AD) spectrum. However, any biomarker alone has not been known to have satisfactory AD predictability. We explored the best combination model with baseline demography, neuropsychology, F-18-fluorodeoxyglucose positron emission tomography (FDG-PET), cerebrospinal fluid (CSF) biomarkers, and apolipoprotein E (APOE) genotype evaluation to predict progression to AD in mild cognitive impairment (MCI) patients. Alongitudinal clinical follow-up (mean, 44 months; range, 1.6-161.7 months) of MCI patients was done. Among 83 MCI patients, 26 progressed to AD (MCI-AD) and 51 did not deteriorate (MCI-Stable). We applied that univariate and multivariate logistic regression analyses, and multistep model selection for AD predictors including biomarkers. In univariate logistic analysis, we selected age, Rey Auditory Verbal Retention Test, parietal glucose metabolic rate, CSF total tau, and presence or not of at least one APOE epsilon 4 allele as predictors. Through multivariate stepwise logistic analysis and model selection, we found the combination of parietal glucose metabolic rate and total tau representing the best model for AD prediction. In conclusion, our findings highlight that the combination of regional glucose metabolic assessment by PET and CSF biomarkers evaluation can significantly improve AD predictive diagnostic accuracy of each respective method.
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| 8. |
- Dentoni, Giacomo, et al.
(författare)
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Mitochondrial Alterations in Neurons Derived from the Murine AppNL-F Knock-In Model of Alzheimer's Disease
- 2022
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 90:2, s. 565-583
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Tidskriftsartikel (refereegranskat)abstract
- Background:Alzheimer’s disease (AD) research has relied on mouse models overexpressing human mutant A βPP; however, newer generation knock-in models allow for physiological expression of amyloid-β protein precursor (AβPP) containing familial AD mutations where murine AβPP is edited with a humanized amyloid-β (Aβ) sequence. The AppNL-F mouse model has shown substantial similarities to AD brains developing late onset cognitive impairment.Objective:In this study, we aimed to characterize mature primary cortical neurons derived from homozygous AppNL-F embryos, especially to identify early mitochondrial alterations in this model.Methods:Primary cultures of AppNL-F neurons kept in culture for 12–15 days were used to measure Aβ levels, secretase activity, mitochondrial functions, mitochondrial-ER contacts, synaptic function, and cell death.Results:We detected higher levels of Aβ42 released from AppNL-F neurons as compared to wild-type neurons. AppNL-F neurons, also displayed an increased Aβ42/Aβ40 ratio, similar to adult AppNL-F mouse brain. Interestingly, we found an upregulation in mitochondrial oxygen consumption with concomitant downregulation in glycolytic reserve. Furthermore, AppNL-F neurons were more susceptible to cell death triggered by mitochondrial electron transport chain inhibition. Juxtaposition between ER and mitochondria was found to be substantially upregulated, which may account for upregulated mitochondrial-derived ATP production. However, anterograde mitochondrial movement was severely impaired in this model along with loss in synaptic vesicle protein and impairment in pre- and post-synaptic function.Conclusion:We show that widespread mitochondrial alterations can be detected in AppNL-F neurons in vitro, where amyloid plaque deposition does not occur, suggesting soluble and oligomeric Aβ-species being responsible for these alterations.
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| 9. |
- Emami Khoonsari, Payam, et al.
(författare)
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Improved Differential Diagnosis of Alzheimer's Disease by Integrating ELISA and Mass Spectrometry-Based Cerebrospinal Fluid Biomarkers
- 2019
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Ingår i: Journal of Alzheimer's Disease. - : IOS PRESS. - 1387-2877 .- 1875-8908. ; 67:2, s. 639-651
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Tidskriftsartikel (refereegranskat)abstract
- Background: Alzheimer's disease (AD) is diagnosed based on a clinical evaluation as well as analyses of classical biomarkers: A beta(42), total tau (t-tau), and phosphorylated tau (p-tau) in cerebrospinal fluid (CSF). Although the sensitivities and specificities of the classical biomarkers are fairly good for detection of AD, there is still a need to develop novel biochemical markers for early detection of AD. Objective: We explored if integration of novel proteins with classical biomarkers in CSF can better discriminate AD from non-AD subjects. Methods: We applied ELISA, mass spectrometry, and multivariate modeling to investigate classical biomarkers and the CSF proteome in subjects (n = 206) with 76 AD patients, 74 mild cognitive impairment (MCI) patients, 11 frontotemporal dementia (FTD) patients, and 45 non-dementia controls. The MCI patients were followed for 4-9 years and 21 of these converted to AD, whereas 53 remained stable. Results: By combining classical CSF biomarkers with twelve novel markers, the area of the ROC curves (AUROCS) of distinguishing AD and MCl/AD converters from non-AD were 93% and 96%, respectively. The FTDs and non-dementia controls were identified versus all other groups with AUROCS of 96% and 87%, respectively. Conclusions: Integration of new and classical CSF biomarkers in a model-based approach can improve the identification of AD, FTD, and non-dementia control subjects.
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| 10. |
- Eriksdotter, Maria, et al.
(författare)
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Plasma Fatty Acid Profiles in Relation to Cognition and Gender in Alzheimer's Disease Patients During Oral Omega-3 Fatty Acid Supplementation : The OmegAD Study
- 2015
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 48:3, s. 805-812
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: ω3 fatty acids (ω3 FAs) may slow the rate of decline in cognitive performance in mild forms of cognitive impairment and Alzheimer's disease (AD). However, the relationship between changes of plasma ω3 FA levels and cognitive performance, as well as effects of gender, are poorly known.OBJECTIVE: To study the effect of 6-month administration of DHA-rich ω3 FA supplementation on plasma FA profiles in patients with mild to moderate AD in relation to cognitive performance and gender. This investigation is part of the OmegAD Study.METHODS: 174 AD patients (74 ± 9 years) were randomized to a daily intake of 2.3 g ω3 FA or placebo for 6 months; subsequently all received the ω3 FA preparation for the next 6 months. Baseline as well as changes in plasma levels of the main ω3 FAs in 165 patients, while receiving ω3 FA supplementation for 6 months, were analyzed for association to cognitive performance (assessed by ADAS-cog and MMSE scores) as well as to gender.RESULTS: Preservation of cognitive functioning, assessed by ADAS-cog or its sub-items (but not MMSE) scores, was significantly associated to increasing plasma ω3 FA levels over time. Thus, the higher ω3 FA plasma levels rose, the lower was the rate of cognitive deterioration. This effect was not related to gender; since although females displayed higher ω3 FA plasma levels than did males after 6 months of supplementation, this difference disappeared when adjusted for body weight.CONCLUSIONS: Since our study suggests dose-response relationships between plasma levels of ω3 FA and preservation of cognition, future ω3 FA trials in patients with mild AD should consider exploring graded (and body weight adjusted) doses of ω3 FA.
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