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Constantin Bouras - One of the best experts on this subject based on the ideXlab platform.
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Neuroanatomic correlates of visual agnosia in Alzheimer’s disease A clinicopathologic study
Neurology, 1999Co-Authors: Panteleimon Giannakopoulos, G. Gold, Jean-pierre Michel, Constantin BourasAbstract:Objective: To examine the neuroanatomic correlates of visual agnosia in AD. Methods: The authors performed an anterograde clinicopathologic study of 23 patients with clinically and neuropathologically confirmed AD in a 305-bed acute care geriatric hospital and a 165-bed acute care psychiatric hospital. The presence of apperceptive visual agnosia was assessed using the Ghent’s overlapping figure test and the Gottschaldt’s hidden figure test. Associative visual agnosia was examined using the conceptual items of the Columbia Mental Maturity Test. Correlations between neurofibrillary tangle (NFT) and Senile Plaque (SP) densities and visual agnosia were studied using forward stepwise logistic regression. Results: A statistically significant relation was found between NFT densities in Brodmann’s areas 18, 19, and 37, and associative visual agnosia, whereas NFT densities in the areas studied did not correlate with the presence of apperceptive visual agnosia. Senile Plaque counts did not correlate with any of the neuropsychological parameters. Conclusions: These results support the existence of a dichotomy between associative and apperceptive agnosia, and show that only the former is related to the damage of secondary and high-order visual association areas in AD. In addition, the results suggest that SP densities do not represent a valuable pathologic correlate of visual agnosia in this disorder.
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neuroanatomic correlates of visual agnosia in alzheimer s disease a clinicopathologic study
Neurology, 1999Co-Authors: Panteleimon Giannakopoulos, G. Gold, Jean-pierre Michel, Constantin BourasAbstract:Objective: To examine the neuroanatomic correlates of visual agnosia in AD. Methods: The authors performed an anterograde clinicopathologic study of 23 patients with clinically and neuropathologically confirmed AD in a 305-bed acute care geriatric hospital and a 165-bed acute care psychiatric hospital. The presence of apperceptive visual agnosia was assessed using the Ghent’s overlapping figure test and the Gottschaldt’s hidden figure test. Associative visual agnosia was examined using the conceptual items of the Columbia Mental Maturity Test. Correlations between neurofibrillary tangle (NFT) and Senile Plaque (SP) densities and visual agnosia were studied using forward stepwise logistic regression. Results: A statistically significant relation was found between NFT densities in Brodmann’s areas 18, 19, and 37, and associative visual agnosia, whereas NFT densities in the areas studied did not correlate with the presence of apperceptive visual agnosia. Senile Plaque counts did not correlate with any of the neuropsychological parameters. Conclusions: These results support the existence of a dichotomy between associative and apperceptive agnosia, and show that only the former is related to the damage of secondary and high-order visual association areas in AD. In addition, the results suggest that SP densities do not represent a valuable pathologic correlate of visual agnosia in this disorder.
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regional distribution of neurofibrillary tangles and Senile Plaques in the cerebral cortex of very old patients
JAMA Neurology, 1995Co-Authors: Panteleimon Giannakopoulos, Jean-pierre Michel, Anneseverine Giannakopoulos, Francois Herrmann, Constantin BourasAbstract:Objectives: To examine the correlations between Senile lesion densities and development of dementia symptoms in very old people. To perform a quantitative neuropathologic evaluation of several cortical and subcortical areas in a series of 29 nonagenarians and centenarians. Patients: Ten patients with no cognitive impairment and 19 patients with clinically overt Alzheimer's disease. Design: Neuropathologic case series. Severity of Alzheimer's disease was assessed with the Mini-Mental State examination and by postmortem chart review using the extended Clinical Dementia Rating Scale. Comparisons between neurofibrillary tangle and Senile Plaque densities in demented and nondemented individuals were performed by analysis of covariance controlling for age at the time of death. Setting: Studies were conducted at the Psychiatric and Geriatric hospitals of the University of Geneva School of Medicine in Geneva, Switzerland. Main Outcome Measure: Correlations between clinical diagnosis and severity of Alzheimer's disease and neuropathologic change densities. Results: Statistically significant differences were found in neurofibrillary tangle densities in the superior parietal, superior temporal, anterior and posterior cingulate cortex, and nucleus basalis of Meynert between nondemented and Alzheimer's disease cases. The superior parietal and posterior cingulate cortex contained significantly higher Senile Plaque counts in demented compared with nondemented cases. In contrast to younger demented cases, the number of Senile Plaques in the neocortex was correlated with the severity of dementia in centenarians. Conclusions: These results indicate that the neuronal degeneration in very old demented patients involves cortical areas usually preserved at the early stages of the dementing process. Senile Plaque formation in certain neocortical areas may be a pathologic hallmark of the severity of dementia in this particular age group.
Panteleimon Giannakopoulos - One of the best experts on this subject based on the ideXlab platform.
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Neuroanatomic correlates of visual agnosia in Alzheimer’s disease A clinicopathologic study
Neurology, 1999Co-Authors: Panteleimon Giannakopoulos, G. Gold, Jean-pierre Michel, Constantin BourasAbstract:Objective: To examine the neuroanatomic correlates of visual agnosia in AD. Methods: The authors performed an anterograde clinicopathologic study of 23 patients with clinically and neuropathologically confirmed AD in a 305-bed acute care geriatric hospital and a 165-bed acute care psychiatric hospital. The presence of apperceptive visual agnosia was assessed using the Ghent’s overlapping figure test and the Gottschaldt’s hidden figure test. Associative visual agnosia was examined using the conceptual items of the Columbia Mental Maturity Test. Correlations between neurofibrillary tangle (NFT) and Senile Plaque (SP) densities and visual agnosia were studied using forward stepwise logistic regression. Results: A statistically significant relation was found between NFT densities in Brodmann’s areas 18, 19, and 37, and associative visual agnosia, whereas NFT densities in the areas studied did not correlate with the presence of apperceptive visual agnosia. Senile Plaque counts did not correlate with any of the neuropsychological parameters. Conclusions: These results support the existence of a dichotomy between associative and apperceptive agnosia, and show that only the former is related to the damage of secondary and high-order visual association areas in AD. In addition, the results suggest that SP densities do not represent a valuable pathologic correlate of visual agnosia in this disorder.
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neuroanatomic correlates of visual agnosia in alzheimer s disease a clinicopathologic study
Neurology, 1999Co-Authors: Panteleimon Giannakopoulos, G. Gold, Jean-pierre Michel, Constantin BourasAbstract:Objective: To examine the neuroanatomic correlates of visual agnosia in AD. Methods: The authors performed an anterograde clinicopathologic study of 23 patients with clinically and neuropathologically confirmed AD in a 305-bed acute care geriatric hospital and a 165-bed acute care psychiatric hospital. The presence of apperceptive visual agnosia was assessed using the Ghent’s overlapping figure test and the Gottschaldt’s hidden figure test. Associative visual agnosia was examined using the conceptual items of the Columbia Mental Maturity Test. Correlations between neurofibrillary tangle (NFT) and Senile Plaque (SP) densities and visual agnosia were studied using forward stepwise logistic regression. Results: A statistically significant relation was found between NFT densities in Brodmann’s areas 18, 19, and 37, and associative visual agnosia, whereas NFT densities in the areas studied did not correlate with the presence of apperceptive visual agnosia. Senile Plaque counts did not correlate with any of the neuropsychological parameters. Conclusions: These results support the existence of a dichotomy between associative and apperceptive agnosia, and show that only the former is related to the damage of secondary and high-order visual association areas in AD. In addition, the results suggest that SP densities do not represent a valuable pathologic correlate of visual agnosia in this disorder.
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regional distribution of neurofibrillary tangles and Senile Plaques in the cerebral cortex of very old patients
JAMA Neurology, 1995Co-Authors: Panteleimon Giannakopoulos, Jean-pierre Michel, Anneseverine Giannakopoulos, Francois Herrmann, Constantin BourasAbstract:Objectives: To examine the correlations between Senile lesion densities and development of dementia symptoms in very old people. To perform a quantitative neuropathologic evaluation of several cortical and subcortical areas in a series of 29 nonagenarians and centenarians. Patients: Ten patients with no cognitive impairment and 19 patients with clinically overt Alzheimer's disease. Design: Neuropathologic case series. Severity of Alzheimer's disease was assessed with the Mini-Mental State examination and by postmortem chart review using the extended Clinical Dementia Rating Scale. Comparisons between neurofibrillary tangle and Senile Plaque densities in demented and nondemented individuals were performed by analysis of covariance controlling for age at the time of death. Setting: Studies were conducted at the Psychiatric and Geriatric hospitals of the University of Geneva School of Medicine in Geneva, Switzerland. Main Outcome Measure: Correlations between clinical diagnosis and severity of Alzheimer's disease and neuropathologic change densities. Results: Statistically significant differences were found in neurofibrillary tangle densities in the superior parietal, superior temporal, anterior and posterior cingulate cortex, and nucleus basalis of Meynert between nondemented and Alzheimer's disease cases. The superior parietal and posterior cingulate cortex contained significantly higher Senile Plaque counts in demented compared with nondemented cases. In contrast to younger demented cases, the number of Senile Plaques in the neocortex was correlated with the severity of dementia in centenarians. Conclusions: These results indicate that the neuronal degeneration in very old demented patients involves cortical areas usually preserved at the early stages of the dementing process. Senile Plaque formation in certain neocortical areas may be a pathologic hallmark of the severity of dementia in this particular age group.
Yasuo Ihara - One of the best experts on this subject based on the ideXlab platform.
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γ secretase activity is associated with braak Senile Plaque stages
American Journal of Pathology, 2020Co-Authors: Nobuto Kakuda, Haruyasu Yamaguchi, Kohei Akazawa, Saori Hata, Toshiharu Suzuki, Hiroyuki Hatsuta, Shigeo Murayama, Satoru Funamoto, Yasuo IharaAbstract:Amyloid β-proteins (Aβs) Aβ1-42 and Aβ1-43 are converted via two product lines of γ-secretase to Aβ1-38 and Aβ1-40. This parallel stepwise processing model of γ-secretase predicts that Aβ1-42 and Aβ1-43, and Aβ1-38 and Aβ1-40 are proportional to each other, respectively. To obtain further insight into the mechanisms of parenchymal Aβ deposition, these four Aβ species were quantified in insoluble fractions of human brains (Brodmann areas 9 to 11) at various Braak Senile Plaque (SP) stages, using specific enzyme-linked immunosorbent assays. With advancing SP stages, the amounts of deposited Aβ1-43 in the brain increased proportionally to those of Aβ1-42. Similarly, the amounts of deposited Aβ1-38 correlated with those of Aβ1-40. Surprisingly, the ratios of deposited Aβ1-38/Aβ1-42 and Aβ1-40/Aβ1-43 were proportional and discriminated the Braak SP stages accurately. This result indicates that the generation of Aβ1-38 and Aβ1-40 decreased and the generation of Aβ1-42 and Aβ1-43 increased with advancing SP stages. Thus, Aβs deposition might depend on γ-secretase activity, as it does in the cerebrospinal fluid. Here, the extracted γ-secretase from Alzheimer disease brains generates an amount of Aβ1-42 and Aβ1-43 compared with cognitively normal brains. This refractory γ-secretase localized in detergent-solubilized fractions from brain cortices. But activity modulated γ-secretase, which decreases Aβ1-42 and Aβ1-43 in the cerebrospinal fluid, localized in detergent-insoluble fractions. These drastic alterations reflect Aβ situation in Alzheimer disease brains.
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dominant and differential deposition of distinct β amyloid peptide species aβn3 pe in Senile Plaques
Neuron, 1995Co-Authors: Takaomi C Saido, Yasuo Ihara, Takeshi Iwatsubo, David M A Mann, Hiroyuki Shimada, Seiichi KawashimaAbstract:Abstract We analyzed an amino-terminal modification of β-amyloid (Aβ) peptide in brain, using anti-Aβ antibodies that distinguish distinct molecular species. Examination of cortical sections from 28 aged individuals with a wide range in Senile Plaque density revealed that a molecular species distinct from the standard Aβ is deposited in the brain in a dominant and differential manner. This modified Aβ peptide (A β N3(pE) ) starts at the 3rd amino-terminal residue of the standard Aβ, glutamate, converted to pyroglutamate through intramolecular dehydration. Because Plaques composed of A β N3(pE) are present in equivalent or greater densities than those composed of standard Aβ bearing the first aminoterminal residue (A β N1 ) and because deposition of the former species appears to precede deposition of the latter, as confirmed with specimens from Down's syndrome patients, the processes involved in A β N3(pE) production and retention may play an early and critical role in Senile Plaque formation.
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dominant and differential deposition of distinct β amyloid peptide species aβn3 pe in Senile Plaques
Neuron, 1995Co-Authors: Takaomi C Saido, Yasuo Ihara, Takeshi Iwatsubo, David M A Mann, Hiroyuki Shimada, Seiichi KawashimaAbstract:We analyzed an amino-terminal modification of beta-amyloid (A beta) peptide in brain, using anti-A beta antibodies that distinguish distinct molecular species. Examination of cortical sections from 28 aged individuals with a wide range in Senile Plaque density revealed that a molecular species distinct from the standard A beta is deposited in the brain in a dominant and differential manner. This modified A beta peptide (A beta N3(pE)) starts at the 3rd aminoterminal residue of the standard A beta, glutamate, converted to pyroglutamate through intramolecular dehydration. Because Plaques composed of A beta N3(pE) are present in equivalent or greater densities than those composed of standard A beta bearing the first amino-terminal residue (A beta N1) and because deposition of the former species appears to precede deposition of the latter, as confirmed with specimens from Down's syndrome patients, the processes involved in A beta N3(pE) production and retention may play an early and critical role in Senile Plaque formation.
Jean-pierre Michel - One of the best experts on this subject based on the ideXlab platform.
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Neuroanatomic correlates of visual agnosia in Alzheimer’s disease A clinicopathologic study
Neurology, 1999Co-Authors: Panteleimon Giannakopoulos, G. Gold, Jean-pierre Michel, Constantin BourasAbstract:Objective: To examine the neuroanatomic correlates of visual agnosia in AD. Methods: The authors performed an anterograde clinicopathologic study of 23 patients with clinically and neuropathologically confirmed AD in a 305-bed acute care geriatric hospital and a 165-bed acute care psychiatric hospital. The presence of apperceptive visual agnosia was assessed using the Ghent’s overlapping figure test and the Gottschaldt’s hidden figure test. Associative visual agnosia was examined using the conceptual items of the Columbia Mental Maturity Test. Correlations between neurofibrillary tangle (NFT) and Senile Plaque (SP) densities and visual agnosia were studied using forward stepwise logistic regression. Results: A statistically significant relation was found between NFT densities in Brodmann’s areas 18, 19, and 37, and associative visual agnosia, whereas NFT densities in the areas studied did not correlate with the presence of apperceptive visual agnosia. Senile Plaque counts did not correlate with any of the neuropsychological parameters. Conclusions: These results support the existence of a dichotomy between associative and apperceptive agnosia, and show that only the former is related to the damage of secondary and high-order visual association areas in AD. In addition, the results suggest that SP densities do not represent a valuable pathologic correlate of visual agnosia in this disorder.
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neuroanatomic correlates of visual agnosia in alzheimer s disease a clinicopathologic study
Neurology, 1999Co-Authors: Panteleimon Giannakopoulos, G. Gold, Jean-pierre Michel, Constantin BourasAbstract:Objective: To examine the neuroanatomic correlates of visual agnosia in AD. Methods: The authors performed an anterograde clinicopathologic study of 23 patients with clinically and neuropathologically confirmed AD in a 305-bed acute care geriatric hospital and a 165-bed acute care psychiatric hospital. The presence of apperceptive visual agnosia was assessed using the Ghent’s overlapping figure test and the Gottschaldt’s hidden figure test. Associative visual agnosia was examined using the conceptual items of the Columbia Mental Maturity Test. Correlations between neurofibrillary tangle (NFT) and Senile Plaque (SP) densities and visual agnosia were studied using forward stepwise logistic regression. Results: A statistically significant relation was found between NFT densities in Brodmann’s areas 18, 19, and 37, and associative visual agnosia, whereas NFT densities in the areas studied did not correlate with the presence of apperceptive visual agnosia. Senile Plaque counts did not correlate with any of the neuropsychological parameters. Conclusions: These results support the existence of a dichotomy between associative and apperceptive agnosia, and show that only the former is related to the damage of secondary and high-order visual association areas in AD. In addition, the results suggest that SP densities do not represent a valuable pathologic correlate of visual agnosia in this disorder.
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regional distribution of neurofibrillary tangles and Senile Plaques in the cerebral cortex of very old patients
JAMA Neurology, 1995Co-Authors: Panteleimon Giannakopoulos, Jean-pierre Michel, Anneseverine Giannakopoulos, Francois Herrmann, Constantin BourasAbstract:Objectives: To examine the correlations between Senile lesion densities and development of dementia symptoms in very old people. To perform a quantitative neuropathologic evaluation of several cortical and subcortical areas in a series of 29 nonagenarians and centenarians. Patients: Ten patients with no cognitive impairment and 19 patients with clinically overt Alzheimer's disease. Design: Neuropathologic case series. Severity of Alzheimer's disease was assessed with the Mini-Mental State examination and by postmortem chart review using the extended Clinical Dementia Rating Scale. Comparisons between neurofibrillary tangle and Senile Plaque densities in demented and nondemented individuals were performed by analysis of covariance controlling for age at the time of death. Setting: Studies were conducted at the Psychiatric and Geriatric hospitals of the University of Geneva School of Medicine in Geneva, Switzerland. Main Outcome Measure: Correlations between clinical diagnosis and severity of Alzheimer's disease and neuropathologic change densities. Results: Statistically significant differences were found in neurofibrillary tangle densities in the superior parietal, superior temporal, anterior and posterior cingulate cortex, and nucleus basalis of Meynert between nondemented and Alzheimer's disease cases. The superior parietal and posterior cingulate cortex contained significantly higher Senile Plaque counts in demented compared with nondemented cases. In contrast to younger demented cases, the number of Senile Plaques in the neocortex was correlated with the severity of dementia in centenarians. Conclusions: These results indicate that the neuronal degeneration in very old demented patients involves cortical areas usually preserved at the early stages of the dementing process. Senile Plaque formation in certain neocortical areas may be a pathologic hallmark of the severity of dementia in this particular age group.
Jean-pierre Timmermans - One of the best experts on this subject based on the ideXlab platform.
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dense core Senile Plaques in the flemish variant of alzheimer s disease are vasocentric
American Journal of Pathology, 2002Co-Authors: Samir Kumarsingh, Johan Van Swieten, Ursula Lubke, Sally Serneels, Kristl Vennekens, Johan M. Kros, Rong Wang, Patrick Cras, Chantal Ceuterick, Jean-pierre TimmermansAbstract:Alzheimer’s disease (AD) is characterized by deposition of -amyloid (A) in diffuse and Senile Plaques, and variably in vessels. Mutations in the A-encoding region of the amyloid precursor protein (APP) gene are frequently associated with very severe forms of vascular A deposition, sometimes also accompanied by AD pathology. We earlier described a Flemish APP (A692G) mutation causing a form of early-onset AD with a prominent cerebral amyloid angiopathy and unusually large Senile Plaque cores. The pathogenic basis of Flemish AD is unknown. By image and mass spectrometric A analyses, we demonstrated that in contrast to other familial AD cases with predominant brain A42, Flemish AD patients predominantly deposit A40. On serial histological section analysis we further showed that the neuritic Senile Plaques in APP692 brains were centered on vessels. Of a total of 2400 Senile Plaque cores studied from various brain regions from three patients, 68% enclosed a vessel, whereas the remainder were associated with vascular walls. These observations were confirmed by electron microscopy coupled with examination of serial semithin plastic sections, as well as three-dimensional observations by confocal microscopy. Diffuse Plaques did not associate with vessels, or with neuritic or inflammatory pathology. Together with earlier in vitro data on APP692, our analyses suggest that the altered biological properties of the Flemish APP and A facilitate progressive A deposition in vascular walls that in addition to causing strokes, initiates formation of dense-core Senile Plaques in the Flemish variant of AD. (Am J Pathol 2002, 161:507–520)
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dense core Senile Plaques in the flemish variant of alzheimer s disease are vasocentric
American Journal of Pathology, 2002Co-Authors: Samir Kumarsingh, Ursula Lubke, Sally Serneels, Kristl Vennekens, Johan M. Kros, Rong Wang, Patrick Cras, Chantal Ceuterick, Johan Van Swieten, Jean-pierre TimmermansAbstract:Alzheimer's disease (AD) is characterized by deposition of beta-amyloid (Abeta) in diffuse and Senile Plaques, and variably in vessels. Mutations in the Abeta-encoding region of the amyloid precursor protein (APP) gene are frequently associated with very severe forms of vascular Abeta deposition, sometimes also accompanied by AD pathology. We earlier described a Flemish APP (A692G) mutation causing a form of early-onset AD with a prominent cerebral amyloid angiopathy and unusually large Senile Plaque cores. The pathogenic basis of Flemish AD is unknown. By image and mass spectrometric Abeta analyses, we demonstrated that in contrast to other familial AD cases with predominant brain Abeta42, Flemish AD patients predominantly deposit Abeta40. On serial histological section analysis we further showed that the neuritic Senile Plaques in APP692 brains were centered on vessels. Of a total of 2400 Senile Plaque cores studied from various brain regions from three patients, 68% enclosed a vessel, whereas the remainder were associated with vascular walls. These observations were confirmed by electron microscopy coupled with examination of serial semi-thin plastic sections, as well as three-dimensional observations by confocal microscopy. Diffuse Plaques did not associate with vessels, or with neuritic or inflammatory pathology. Together with earlier in vitro data on APP692, our analyses suggest that the altered biological properties of the Flemish APP and Abeta facilitate progressive Abeta deposition in vascular walls that in addition to causing strokes, initiates formation of dense-core Senile Plaques in the Flemish variant of AD.
