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- Andreasen, Niels, et al.
(author)
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Neuroinflammation Screening in Immunotherapy Trials against Alzheimer's Disease.
- 2010
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In: International journal of Alzheimer's disease. - : Hindawi Limited. - 2090-0252. ; :638379
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Journal article (peer-reviewed)abstract
- Due to side effects in the form of meningoencephalitis in the interrupted phase II AN1792 trial of active antiamyloid β(Aβ) immunization against Alzheimer's disease (AD), there has been concern that anti-Aβ immunization may cause destructive neuroinflammation. Here, we report on two patients fulfilling clinical AD criteria who were diagnosed with Lyme neuroborreliosis during screening before inclusion in anti-Aβ immunotherapy trials. The two cases illustrate the necessity of careful biochemical screening for neuroinflammatory/neuroinfectious conditions before an AD diagnosis is made and before clinical AD patients are included in trials of therapy that could impact the immune system. Should the two cases have been included and deteriorated, additional investigations might have led to the erroneous conclusion that therapy-induced meningoencephalitis had occurred.
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- Bjerke, Maria, 1977, et al.
(author)
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Confounding factors influencing amyloid Beta concentration in cerebrospinal fluid.
- 2010
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In: International journal of Alzheimer's disease. - : Hindawi Limited. - 2090-0252. ; 2010
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Journal article (peer-reviewed)abstract
- Background. Patients afflicted with Alzheimer's disease (AD) exhibit a decrease in the cerebrospinal fluid (CSF) concentration of the 42 amino acid form of beta-amyloid (Abeta(42)). However, a high discrepancy between different centers in measured Abeta(42) levels reduces the utility of this biomarker as a diagnostic tool and in monitoring the effect of disease modifying drugs. Preanalytical and analytical confounding factors were examined with respect to their effect on the measured Abeta(42) level. Methods. Aliquots of CSF samples were either treated differently prior to Abeta(42) measurement or analyzed using different commercially available xMAP or ELISA assays. Results. Confounding factors affecting CSF Abeta(42) levels were storage in different types of test tubes, dilution with detergent-containing buffer, plasma contamination, heat treatment, and the origin of the immunoassays used for quantification. Conclusion. In order to conduct multicenter studies, a standardized protocol to minimize preanalytical and analytical confounding factors is warranted.
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5. |
- Chalbot, Sonia, et al.
(author)
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Blood-cerebrospinal fluid barrier permeability in Alzheimer's disease.
- 2011
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In: Journal of Alzheimer's disease : JAD. - 1875-8908. ; 25:3, s. 505-15
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Journal article (peer-reviewed)abstract
- The role of blood-cerebrospinal fluid barrier (BCB) dysfunction in Alzheimer's disease (AD) has been addressed but not yet established. We evaluated the BCB integrity in 179 samples of cerebrospinal fluid (CSF) retrospectively collected from AD patients and control cases using both CSF/serum albumin ratio (QAlb) and CSF secretory Ca2+-dependent phospholipase A2 (sPLA2) activity. These analyses were supplemented with the measurement of total tau, amyloid-β1-42 (Aβ1-42), and ubiquitin CSF levels. We found that due to its higher sensitivity, CSF sPLA2 activity could 1) discriminate AD from healthy controls and 2) showed BCB impairment in neurological control cases while QAlb could not. Moreover, the CSF sPLA2 activity measurement showed that around half of the AD patients were characterized by a BCB impairment. The BCB dysfunction observed in AD was independent from Mini-Mental State Examination score as well as CSF levels of total tau, Aβ1-42, and ubiquitin. Finally, the BCB dysfunction was not limited to any of the CSF biomarkers-based previously identified subgroups of AD. These results suggest that the BCB damage occurs independent of and probably precedes both Aβ and tau pathologies in a restricted subgroup of AD patients.
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7. |
- Darreh-Shori, Taher, et al.
(author)
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Differential levels of apolipoprotein E and butyrylcholinesterase show strong association with pathological signs of Alzheimer's disease in the brain in vivo
- 2011
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In: Neurobiology of Aging. - : Elsevier. - 0197-4580 .- 1558-1497. ; 32:12, s. 2320.e15-2320.e32
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Journal article (peer-reviewed)abstract
- Recently, we reported that 3 of the known risk factors of Alzheimer's disease (AD), i.e., advanced age, apolipoprotein E (ApoE) ε4, and female gender, are associated with differential levels of ApoE proteins and butyrylcholinesterase (BuChE) in the cerebrospinal fluid (CSF) of AD patients. The ApoE ε4 allele and certain BuChE polymorphisms synergistically affect the conversion rate of mild cognitive impairment (MCI) to AD. Here, we investigated interrelationships between ApoE and BuChE levels, and pathological markers of AD in vivo. CSF from patients with probable AD, assessed for cerebral glucose metabolism (CMRglc; n = 50) and Pittsburgh compound B (PIB) retention (β-amyloid [Aβ] load, n = 29) by positron emission tomography (PET), was used for measurement of BuChE, ApoE, Aβ, tau, phosphorylated tau (P-tau) and interleukin-1β (IL-1β) levels. Levels of ApoE and BuChE strongly correlated with CMRglc (fluorodeoxyglucose [FDG]-PET, r = 0.54, p < 0.0001, n = 50), cerebral Aβ load (PIB retention, r = 0.73, p < 0.0001, n = 29), and CSF P-tau (r = 0.73, p < 0.0001, n = 33). High ApoE protein was tied to low CMRglc and high PIB retention and P-tau. BuChE levels had opposite relationships. Other CSF covariates were levels of interleukin-1β and Aβ42peptide. The pattern of the patients' cognitive Z-scores strongly supported these observations. High ApoE protein was also linked to changes in 3 of the biodynamic properties of BuChE. In vitro analysis indicated that high ApoE protein levels were related to an increased pool of dormant BuChE molecules with an abnormally high intrinsic catalytic rate in CSF, which was “turned on” by excess Aβ peptides. The findings suggest that abnormally high levels of ApoE may play a causative role in the pathological events of AD, particularly those involving the early cholinergic deficit in the AD brain, through modulation of cholinesterases activities, hence disturbing the acetylcholine-dependent activity of neurons and nonexcitable cells such as glial cells.
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8. |
- Duits, Flora H., et al.
(author)
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The cerebrospinal fluid "Alzheimer profile": Easily said, but what does it mean?
- 2014
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In: Alzheimer's & Dementia. - : Elsevier. - 1552-5260 .- 1552-5279. ; 10:6, s. 713-723
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Journal article (peer-reviewed)abstract
- Background: We aimed to identify the most useful definition of the "cerebrospinal fluid Alzheimer profile," based on amyloid-beta(1-42) (A beta(42)), total tau, and phosphorylated tau (p-tau), for diagnosis and prognosis of Alzheimers disease (AD). Methods: We constructed eight Alzheimer profiles with previously published combinations, including regression formulas and simple ratios. We compared their diagnostic accuracy and ability to predict dementia due to AD in 1385 patients from the Amsterdam Dementia Cohort. Results were validated in an independent cohort (n = 1442). Results: Combinations outperformed individual biomarkers. Based on the sensitivity of the best performing regression formulas, cutoffs were chosen at 0.52 for the tau/A beta(42) ratio and 0.08 for the p-tau/A beta(42) ratio. Ratios performed similar to formulas (sensitivity, 91%-93%; specificity, 81%-84%). The same combinations best predicted cognitive decline in mild cognitive impairment patients. Validation confirmed these results, especially regarding the tau/A beta(42) ratio. Conclusions: A tau/A beta(42) ratio of greater than0.52 constitutes a robust cerebrospinal fluid Alzheimer profile. We recommend using this ratio to combine biomarkers.
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- Eriksdotter-Jönhagen, Maria, et al.
(author)
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Encapsulated cell biodelivery of nerve growth factor to the Basal forebrain in patients with Alzheimer's disease.
- 2012
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In: Dementia and geriatric cognitive disorders. - : S. Karger AG. - 1421-9824 .- 1420-8008. ; 33:1, s. 18-28
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Journal article (peer-reviewed)abstract
- Degeneration of cholinergic neurons in the basal forebrain correlates with cognitive decline in patients with Alzheimer's disease (AD). Targeted delivery of exogenous nerve growth factor (NGF) has emerged as a potential AD therapy due to its regenerative effects on the basal forebrain cholinergic neurons in AD animal models. Here we report the results of a first-in-man study of encapsulated cell (EC) biodelivery of NGF to the basal forebrain of AD patients with the primary objective to explore safety and tolerability.
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10. |
- García-Ayllón, María-Salud, et al.
(author)
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CSF Presenilin-1 complexes are increased in Alzheimer's disease.
- 2013
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In: Acta neuropathologica communications. - : Springer Science and Business Media LLC. - 2051-5960. ; 1:1
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Journal article (peer-reviewed)abstract
- Presenilin-1 (PS1) is the active component of the amyloid precursor protein cleaving γ-secretase complex. PS1 protein is a transmembrane protein containing multiple hydrophobic regions which presence in cerebrospinal fluid (CSF) has not been measured to date. This study assesses whether PS1 and other components of the γ-secretase complex are present in CSF.
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