| 1. |
- Baker, Crystal, et al.
(författare)
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Effects of Alzheimer's peptide and alpha 1-antichymotrypsin on astrocyte gene expression
- 2007
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 28:1, s. 51-61
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Tidskriftsartikel (refereegranskat)abstract
- We employed gene array technology to investigate the effects of alpha 1-antichymotrypsin (ACT), soluble or fibrillar Alzheimer's peptide (A beta(1-42)) alone and the combination of ACT/A beta(1-42) on human astrocytes. Using a 1.2-fold change as significance threshold, 398 astrocyte genes showed altered expression in response to these treatments compared to controls. Of the 276 genes affected by the ACT/soluble A beta(1-42) combination, 195 (70.6%) were suppressed. The ACT/fibrillar A beta(1-42) combination affected expression of 64 genes of which 58 (90.5%) were up-regulated. The most prominent gene expression changes in response to the ACT/soluble A beta(1-42), were the down-regulation of at least 60 genes involved in transcription, signal transduction, apoptosis and neurogenesis. The ACT/fibril A beta(1-42) increased the expression of genes involved in transcription regulation and signal transduction. Surprisingly, gene expression of astrocytes exposed to soluble or fibrillar A beta(1-42) alone was largely unaffected. Thus, the molecular forms generated by the combination of ACT/A beta(1-42) alter expression of astrocyte genes more profoundly in breadth and magnitude than soluble or fibrillar A beta(1-42) alone, suggesting that pathogenic effects of A beta(1-42) may occur as a consequence of its association with other proteins. (c) 2005 Elsevier Inc. All rights reserved.
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| 2. |
- Boström, Fredrik, et al.
(författare)
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CSF Mg and Ca as diagnostic markers for dementia with Lewy bodies.
- 2008
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Ingår i: Neurobiology of aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 30:8, s. 1265-1271
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Tidskriftsartikel (refereegranskat)abstract
- Accumulating evidence implicates a role for altered metal homeostasis in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD). However, few investigations have addressed this issue in dementia with Lewy bodies (DLB). The aim of the present study was to investigate metal concentrations in cerebrospinal fluid (CSF) and plasma from patients with DLB and other neurodegenerative disorders. To that end, CSF and plasma samples were collected from 29 patients with DLB, 174 patients with AD, 90 patients with AD with minor vascular components, and 51 healthy volunteers. Total concentrations of Mg, Ca, Mn, Fe, Cu, Zn, Rb, Sr, and Cs were determined using mass spectrometry. Patients with DLB had elevated Ca and Mg levels in CSF and Mg levels in plasma as compared to all other groups (p<0.001). Furthermore, a combination of CSF-Mg and CSF-Ca could distinguish DLB from AD with a sensitivity of 93% and a specificity of 85%. Cu levels in both CSF and plasma tended to be higher in DLB compared to the other groups, but these trends failed to reach significance after correction for multiple comparisons. Mn, Fe, Zn, Rb, and Sr concentration in CSF or plasma were similar in all groups. The observed elevations of CSF-Mg, CSF-Ca and CSF-Cu may contribute to or be associated with the neurodegenerative process in DLB. Furthermore, determination of CSF-Mg and CSF-Ca concentration may be a valuable tool in distinguishing DLB from AD.
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| 3. |
- Buchhave, Peder, et al.
(författare)
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Soluble TNF receptors are associated with Abeta metabolism and conversion to dementia in subjects with mild cognitive impairment.
- 2010
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 31:11, s. 1877-1884
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: There is evidence supporting that tumor necrosis factor receptor (TNFR)-signaling can induce production of beta-amyloid (Abeta) in the brain. Moreover, amyloid-induced toxicity has been shown to be dependent on TNFR-signaling. However, it is still unclear whether TNFRs are involved in the early stages of dementia. METHODS: We analyzed soluble TNFR1 and TNFR2 levels in plasma and cerebrospinal fluid (CSF) at baseline in 137 patients with mild cognitive impairment (MCI) and 30 age-matched controls. The MCI patients were followed for 4-6 years with an incidence of Alzheimer's disease (AD) or vascular dementia (VaD) of 15% per year. RESULTS: The patients with MCI who subsequently developed these forms of dementias had higher levels of sTNFR1 and sTNFR2 in both CSF and plasma already at baseline when compared to age-matched controls (p<0.05). In the CSF of MCI subjects and controls the levels of both sTNFR1 and sTNFR2 correlated strongly with beta-site APP-cleaving enzyme 1 (BACE1) activity (r(s)=0.53-0.68, p<0.01) and Abeta 40 levels (r(s)=0.59-0.71, p<0.001). Similarly, both sTNFRs were associated with Abeta 40 (r(s)=0.39-0.46, p<0.05) in plasma. Finally, the levels of both sTNFRs correlated with the axonal damage marker tau in the CSF of MCI subjects and controls (r(s)=0.57-0.83, p<0.001). CONCLUSION: TNFR-signaling might be involved in the early pathogenesis of AD and VaD, and could be associated with beta-amyloid metabolism.
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| 4. |
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| 5. |
- Clerx, Lies, et al.
(författare)
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Measurements of medial temporal lobe atrophy for prediction of Alzheimer's disease in subjects with mild cognitive impairment
- 2013
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 34:8, s. 2003-2013
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Tidskriftsartikel (refereegranskat)abstract
- Our aim was to compare the predictive accuracy of 4 different medial temporal lobe measurements for Alzheimer's disease (AD) in subjects with mild cognitive impairment (MCI). Manual hippocampal measurement, automated atlas-based hippocampal measurement, a visual rating scale (MTA-score), and lateral ventricle measurement were compared. Predictive accuracy for AD 2 years after baseline was assessed by receiver operating characteristics analyses with area under the curve as outcome. Annual cognitive decline was assessed by slope analyses up to 5 years after baseline. Correlations with biomarkers in cerebrospinal fluid (CSF) were investigated. Subjects with MCI were selected from the Development of Screening Guidelines and Clinical Criteria for Predementia AD (DESCRIPA) multicenter study (n = 156) and the single-center VU medical center (n = 172). At follow-up, area under the curve was highest for automated atlas-based hippocampal measurement (0.71) and manual hippocampal measurement (0.71), and lower for MTA-score (0.65) and lateral ventricle (0.60). Slope analysis yielded similar results. Hippocampal measurements correlated with CSF total tau and phosphorylated tau, not with beta-amyloid 1-42. MTA-score and lateral ventricle volume correlated with CSF beta-amyloid 1-42. We can conclude that volumetric hippocampal measurements are the best predictors of AD conversion in subjects with MCI. (c) 2013 Elsevier Inc. All rights reserved.
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| 6. |
- Ewers, Michael, et al.
(författare)
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Body mass index is associated with biological CSF markers of core brain pathology of Alzheimer's disease
- 2012
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 33:8, s. 1599-1608
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Tidskriftsartikel (refereegranskat)abstract
- Weight changes are common in aging and Alzheimer's disease (AD) and postmortem findings suggest a relation between lower body mass index (BMI) and increased AD brain pathology. In the current multicenter study, we tested whether lower BMI is associated with higher core AD brain pathology as assessed by cerebrospinal fluid (CSF)-based biological markers of AD in 751 living subjects: 308 patients with AD, 296 subjects with amnestic mild cognitive impairment (MCI), and 147 elderly healthy controls (HC). Based upon a priori cutoff values on CSF concentration of total tau and beta-amyloid (A beta(1-42)), subjects were binarized into a group with abnormal CSF biomarker signature (CSF+) and those without (CSF-). Results showed that BMI was significantly lower in the CSF+ when compared with the CSF- group (F = 27.7, df = 746, p < 0.001). There was no interaction between CSF signature and diagnosis or apolipoprotein E (ApoE) genotype. In conclusion, lower BMI is indicative of AD pathology as assessed with CSF-based biomarkers in demented and nondemented elderly subjects. Published by Elsevier Inc.
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| 7. |
- Hansson, Oskar, et al.
(författare)
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Combined rCBF and CSF biomarkers predict progression from mild cognitive impairment to Alzheimer's disease.
- 2009
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Ingår i: Neurobiology of aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 30:2, s. 165-73
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to identify preclinical Alzheimer's disease (AD) in patients with mild cognitive impairment (MCI) using measurements of both regional cerebral blood flow (rCBF) and cerebrospinal fluid (CSF) biomarkers. Baseline rCBF assessments ((133)Xe method) were performed in 70 patients with MCI who were cognitively stable for 4-6 years, 69 patients with MCI who subsequently developed AD, and 33 healthy individuals. CSF was collected at baseline and analyzed for beta-amyloid(1-42), total tau and phophorylated tau. In contrast to patients with stable MCI, those who subsequently developed AD had decreased rCBF in the temporo-parietal cortex already at baseline. The relative risk of future progression to AD was particularly increased in MCI patients with decreased rCBF in parietal cortex (hazard ratio 3.1, P<0.0001). Subjects with pathological levels of both CSF tau and beta-amyloid(1-42) were also at high risk of developing AD (hazard ratio 13.4, P<0.0001). The MCI patients with a combination of decreased parietal rCBF and pathological CSF biomarkers at baseline had a substantially increased risk of future development of AD, with a hazard ratio of 24.3 (P<0.0001), when compared to those with normal CSF biomarkers. Moreover, decreased parietal rCBF (but not CSF biomarkers) was associated with a more rapid progression to AD. In conclusion, the combination of rCBF and CSF biomarkers improves the risk assessment of progression to AD in patients with MCI.
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| 8. |
- Hansson, Oskar, et al.
(författare)
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Evaluation of plasma Abeta(40) and Abeta(42) as predictors of conversion to Alzheimer's disease in patients with mild cognitive impairment.
- 2010
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Ingår i: Neurobiology of aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 31:3, s. 357-67
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Tidskriftsartikel (refereegranskat)abstract
- Numerous studies have shown a marked decrease of beta-amyloid(42) (Abeta(42)) in the cerebrospinal fluid (CSF) of patients with incipient Alzheimer's disease (AD). However, studies on Abeta in plasma are contradictory, and show very marginal differences between patients and controls. Here, we analyzed plasma samples using a new multiplex immunoassay for simultaneous analysis of Abeta(1-40), Abeta(n-40), Abeta(1-42), and Abeta(n-42). The plasma samples were obtained at baseline from two independent cohorts of patients with mild cognitive impairment (MCI) and age-matched controls. In the first cohort, 41% of the 117 MCI cases converted to AD during a clinical follow-up period of 4-7 years. In the second cohort, 14% of the 110 MCI subjects developed AD during a clinical follow-up period of 2-4 years. None of the plasma Abeta isoforms differed between MCI patients that subsequently developed AD and healthy controls or stable MCI patients. The Cox proportional hazards model did not reveal any differences in the probability of progression from MCI to AD related to plasma Abeta levels. In contrast, low levels of Abeta(1-42) in CSF were strongly associated with increased risk of future AD. The absence of a change in plasma Abeta in incipient AD, despite the marked change in CSF, may be explained by the lack of a correlation between the levels of Abeta(1-42) in CSF and plasma. In conclusion, the results show that CSF biomarkers are better predictors of progression to AD than plasma Abeta isoforms.
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| 9. |
- Jacobs, Heidi I. L., et al.
(författare)
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The association between white matter hyperintensities and executive decline in mild cognitive impairment is network dependent
- 2012
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 33:1, s. 1-201
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Tidskriftsartikel (refereegranskat)abstract
- White matter hyperintensities (WMH) in Mild Cognitive Impairment (MCI) have been associated with impaired executive functioning, although contradictory findings have been reported. The aim of this study was to examine whether WMH location influenced the relation between WMH and executive functioning in MCI participants (55-90 years) in the European multicenter memory-clinic-based DESCRIPA study, who underwent MRI scanning at baseline (N = 337). Linear mixed model analysis was performed to test the association between WMH damage in three networks (frontal-parietal, frontal-subcortical and frontal-parietal-subcortical network) and change in executive functioning over a 3-year period. WMH in the frontal-parietal and in the frontal-parietal-subcortical network were associated with decline in executive functioning. However, the frontal-subcortical network was not associated with change in executive functioning. Our results suggest that parietal WMH are a significant contributor to executive decline in MCI and that investigation of WMH in the cerebral networks supporting cognitive functions provide a new way to differentiate stable from cognitive declining MCI individuals. (C) 2012 Elsevier Inc. All rights reserved.
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| 10. |
- Simonsen, A H, et al.
(författare)
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Identification of a novel panel of cerebrospinal fluid biomarkers for Alzheimer's disease.
- 2008
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Ingår i: Neurobiology of aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 29:7, s. 961-8
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Tidskriftsartikel (refereegranskat)abstract
- An early and accurate diagnosis of Alzheimer's disease (AD) is required to initiate symptomatic treatment with currently approved drugs and will be of even greater importance if disease modifying compounds in development display a clinical effect. Protein profiles of human cerebrospinal fluid samples from AD patients (n=95) and population-based healthy controls (n=72) were analyzed by SELDI-TOF-MS in order to discover and characterize novel candidate biomarker combinations that differentiate AD patients from normal aging in this explorative study. Thirty candidate biomarkers (ROC AUC>0.7) were discovered that could differentiate patients with AD from healthy controls. Protein sequence determination and positive identification of 15 biomarkers revealed potential associations between the identified markers and AD pathogenesis. A multi-marker combination of five peaks could distinguish AD from healthy control individuals with high sensitivity (97%) and specificity (98%). The panel of five markers was tested on a blinded independent data set of 30 AD samples and 28 controls giving 100% sensitivity and 97% specificity. This novel panel of biomarkers could potentially be used to improve the accuracy of diagnosis of AD.
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