| 1. |
- 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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| 2. |
- Koivisto, Anne M, et al.
(författare)
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Poor Cognitive Outcome in Shunt-Responsive Idiopathic Normal Pressure Hydrocephalus
- 2013
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Ingår i: Neurosurgery. - 0148-396X .- 1524-4040. ; 72:1, s. 1-8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:: Idiopathic normal pressure hydrocephalus (iNPH) causes cognitive decline that can be alleviated by shunting, but long-term outcome studies are scarce. OBJECTIVE:: To elucidate the long-term cognitive condition of shunt-responsive iNPH patients. METHODS:: The follow-up data (Kuopio University Hospital NPH Registry) of 146 patients diagnosed with iNPH by clinical and radiological examination, 24-hour intraventricular pressure monitoring, frontal cortical biopsy, and response to the shunt were analyzed for signs of dementia. The Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition, and specified memory disorder criteria were used. Median follow-up was 4.8 years. RESULTS:: At the end of follow-up, 117 (80%) of the 146 iNPH patients had cognitive decline and 67 (46%) had clinical dementia. The most common clinical diagnoses were Alzheimer disease and vascular dementia. In multivariate analysis of the 146 iNPH patients, memory deficit as a first symptom before shunt (odds ratio [OR] 18.3; 95% confidence interval [CI] 1.9-175), male sex (OR 3.29; 95% CI 1.11-9.73), age (OR 1.17 year; 95% CI 1.07-1.28), and follow-up time (OR 1.20 year; 95% CI 1.02-1.40) predicted dementia. Interestingly, 8 (5%) iNPH patients had dementia without any signs of other neurodegenerative diseases in clinical, neuroradiological, or brain biopsy evaluation. These patients initially presented a full triad of symptoms, with gait disturbance being the most frequent initial symptom followed by deterioration in cognition. CONCLUSION:: The novel findings were (a) a significant risk of dementia in iNPH initially responsive to cerebrospinal fluid shunt, (b) cognitive impairment most commonly due to iNPH-related dementia followed by concurrent degenerative brain disease, and (c) a subgroup with dementia related to iNPH without comorbidities. ABBREVIATIONS:: Aβ, amyloid betaAD, Alzheimer diseaseCI, confidence intervalHPτ, hyperphosphorylated tauICP, intracranial pressureiNPH, idiopathic normal pressure hydrocephalusKUH, Kuopio University HospitalNPH, normal pressure hydrocephalusVaD, vascular dementia.
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| 3. |
- Leinonen, Ville, et al.
(författare)
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Cortical Brain Biopsy in Long-Term Prognostication of 468 Patients with Possible Normal Pressure Hydrocephalus
- 2012
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Ingår i: Neuro-degenerative diseases. - : S. Karger AG. - 1660-2862 .- 1660-2854. ; 10:1-4, s. 166-169
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Tidskriftsartikel (refereegranskat)abstract
- Normal pressure hydrocephalus (NPH) can be alleviated by cerebrospinal fluid shunting but the differential diagnosis and patient selection are challenging. Intraventricular intracranial pressure monitoring as part of the diagnostic workup as well as shunting enable to obtain cortical brain biopsies to detect amyloid-β (Aβ) and hyperphosphorylated tau (HPτ), the hallmark lesions of Alzheimer's disease (AD). In possible NPH, Aβ alone indicates an increased risk of AD and when present with HPτ probable AD, but the effect of those brain lesions on survival is not known. The aim of this study was to evaluate the predictive value of brain biopsy for the long-term outcome of possible NPH. Between 1991 and 2006, the Neurosurgery Department of the Kuopio University Hospital evaluated 468 patients for possible NPH by intraventricular intracranial pressure monitoring and frontal cortical brain biopsy immunostained against Aβ and HPτ. All patients were followed up until the end of 2008 (n = 201) or death (n = 267) with a median follow-up of 4.6 years (range 0-17). Logistic regression analysis with Cox models was applied. Out of the 468 cases, Aβ was detected in 197 (42%) cortical biopsies, and together with HPτ in 44 (9%). Aβ alone indicated increased risk of AD and with HPτ probable AD, but it did not affect survival. Vascular aetiology was the most frequent cause of death. Cortical biopsy findings indicate that NPH is at present a heterogeneous syndrome and has notable overlapping with AD. Brain biopsy did not predict survival but may open a novel research window to study the pathobiology of neurodegeneration.
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| 4. |
- Pyykkö, Okko T, et al.
(författare)
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Cerebrospinal fluid biomarker and brain biopsy findings in idiopathic normal pressure hydrocephalus
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:3, s. e91974-
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To investigate the role of soluble APP (sAPP) and amyloid beta (Ab) isoforms, proinflammatory cytokines, and biomarkers of neuronal damage in the cerebrospinal fluid (CSF) in relation to brain biopsy Ab and hyperphosphorylated tau (HPt) findings. Methods: The study population comprised 102 patients with possible NPH with cortical brain biopsies, ventricular and lumbar CSF samples, and DNA available. The final clinical diagnoses were: 53 iNPH (91% shunt-responders), 26 AD (10 mixed iNPH+AD), and 23 others. Biopsy samples were immunostained against Ab and HPt. CSF levels of AD-related biomarkers (Ab42, p-tau, total tau), non-AD-related Ab isoforms (Ab38, Ab40), sAPP isoforms (sAPPa, sAPPb), proinflammatory cytokines (several interleukins (IL), interferon-gamma, monocyte chemoattractant protein-1, tumor necrosis factor-alpha) and biomarkers of neuronal damage (neurofilament light and myelin basic protein) were measured. All patients were genotyped for APOE. Results: Lumbar CSF levels of sAPP alpha were lower (p<0.05) in patients with shunt-responsive iNPH compared to non-iNPH patients. sAPPb showed a similar trend (p = 0.06). CSF sAPP isoform levels showed no association to Ab or HPt in the brain biopsy. Quantified Ab load in the brain biopsy showed a negative correlation with CSF levels of Ab42 in ventricular (r = 20.295, p = 0.003) and lumbar (r = 20.356, p = 0.01) samples, while the levels of Ab38 and Ab40 showed no correlation. CSF levels of proinflammatory cytokines and biomarkers of neuronal damage did not associate to the brain biopsy findings, diagnosis, or shunt response. Higher lumbar/ventricular CSF IL-8 ratios (p<0.001) were seen in lumbar samples collected after ventriculostomy compared to the samples collected before the procedure. Conclusions: The role of sAPP isoforms in iNPH seems to be independent from the amyloid cascade. No neuroinflammatory background was observed in iNPH or AD.
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