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D P Perl

Publications and source records attributed to D P Perl.

At least 19 recordsLinked to original sources

Coronary artery disease is associated with Alzheimer disease neuropathology in APOE4 carriers.

OBJECTIVE: To examine the associations between postmortem Alzheimer disease (AD) neuropathology and autopsy-verified cardiovascular disease. METHODS: The authors examined 99 subjects (mean age at death = 87.6; SD = 8.7) from the Mount Sinai School of Medicine Department of Psychiatry Brain Bank who were devoid of cerebrovascular disease-associated lesions or of non-AD-related neuropathology. Density of neuritic plaques (NPs) and neurofibrillary tangles (NFTs) as well as coronary artery and aortic atherosclerosis, left ventricular wall thickness, and heart weight were measured. Partial correlations were used to assess the associations of the four cardiovascular variables with NPs and NFTs in the hippocampus, entorhinal cortex, and multiple regions of the cerebral cortex after controlling for age at death, sex, dementia severity, body mass index, and ApoE genotype. These analyses were also repeated separately for ApoE4 carriers and noncarriers. RESULTS: The extent of coronary artery disease and to a lesser extent atherosclerosis were significantly associated with the density of cardinal neuropathologic lesions of AD in this autopsy sample (significant correlations between 0.22 and 0.29). These associations were more pronounced for the ApoE4 allele carriers (n = 42; significant correlations between 0.34 and 0.47). CONCLUSIONS: The degree of coronary artery disease is independently associated with the cardinal neuropathological lesions of Alzheimer disease. These associations are primarily attributable to individuals with the ApoE4 allele.

Aged, 80 and over↗

Dissociation of neuropathology from severity of dementia in late-onset Alzheimer disease.

BACKGROUND: Little is known about Alzheimer disease at advanced ages, although its incidence continues to increase at least through the ninth decade of life. OBJECTIVE: To examine the effects of age on the relationship between clinical dementia severity and neuropathologic hallmarks in a large sample spanning the full age range. METHODS: The authors assessed 81 subjects during life for dementia severity, and examined their brains. They analyzed plaque and tangle burden, as well as the activities of the cholinergic marker enzymes acetylcholinesterase (AChE) and choline acetyltransferase (ChAT), in relation to age at death and the clinical severity of dementia. RESULTS: Dementia severity was strongly related to plaque and tangle burden in relatively young patients (aged < 75 years), but this correlation diminished with age and disappeared in the ninth decade of life. Among the oldest patients studied, there was no difference in plaque and tangle load between the mild and severe dementia cases. This interaction (p < 0.0001 for plaque density) was not observed for the cholinergic markers ChAT and AChE. CONCLUSION: The nature or expression of Alzheimer disease may be different in severely demented older patients, who have equal cholinergic deficits but significantly lower plaque and tangle burden. If confirmed in a prospective study, these findings have diagnostic and therapeutic implications.

Acetylcholine↗

The sweet thing about Type 1 diabetes: a cryoprotective evolutionary adaptation.

The reasons for the uneven worldwide distribution of Type 1 diabetes mellitus have yet to be fully explained. Epidemiological studies have shown a higher prevalence of Type 1 diabetes in northern Europe, particularly in Scandinavian countries, and Sardinia. Recent animal research has uncovered the importance of the generation of elevated levels of glucose, glycerol and other sugar derivatives as a physiological means for cold adaptation. High concentrations of these substances depress the freezing point of body fluids and prevent the formation of ice crystals in cells through supercooling, thus acting as a cryoprotectant or antifreeze for vital organs as well as in their muscle tissue. In this paper, we hypothesize that factors predisposing to elevated levels of glucose, glycerol and other sugar derivatives may have been selected for, in part, as adaptive measures in exceedingly cold climates. This cryoprotective adaptation would have protected ancestral northern Europeans from the effects of suddenly increasingly colder climates, such as those believed to have arisen around 14,000 years ago and culminating in the Younger Dryas. When life expectancy was short, factors predisposing to Type 1 diabetes provided a survival advantage. However, deleterious consequences of this condition have become significant only in more modern times, as life expectancy has increased, thus outweighing their protective value. Examples of evolutionary adaptations conferring selection advantages against human pathogens that result in deleterious effects have been previously reported as epidemic pathogenic selection (EPS). Such proposed examples include the cystic fibrosis mutations in the CFTR gene bestowing resistance to Salmonella typhi and hemochromatosis mutations conferring protection against iron-seeking intracellular pathogens. This paper is one of the first accounts of a metabolic disorder providing a selection advantage not against a pathogenic stressor alone, but rather against a climatic change. We thus believe that the concept of EPS should now include environmental factors that may be nonorganismal in nature. In so doing we propose that factors resulting in Type 1 diabetes be considered a result of environmental pathogenic selection (EnPS).

Acclimatization↗

Tangle and neuron numbers, but not amyloid load, predict cognitive status in Alzheimer's disease.

OBJECTIVE: To examine the relationship between stereologic estimates of AD-related pathology and severity of cognitive deficits in brain aging. BACKGROUND: Previous studies reported substantial contributions of neurofibrillary tangles (NFT), amyloid deposits, and neuronal loss to the development of dementia. However, the prediction of cognitive status based on nonstereologic quantification of these measures has led to conflicting results. Such studies have measured densities, rather than absolute numbers, and most do not take into account the potential interaction between the above pathologic hallmarks in a global multivariate analysis. METHODS: Clinicopathologic study in 22 elderly cases. Cognitive status assessed prospectively using the Mini-Mental State Examination (MMSE); stereologic assessment of NFT, unaffected neurons, and total amyloid volume in the CA1 field of the hippocampus, entorhinal cortex, and area 9. Statistical analysis was performed using both univariate and multivariate linear regression models. RESULTS: High total NFT counts but not amyloid volume were strongly associated with a lower number of unaffected neurons in all areas studied. A high proportion of variability in MMSE scores was explained by NFT and neuronal counts in the CA1 field (83% and 85.4%), entorhinal cortex (87.8% and 83.7%), and area 9 (87% and 79%); amyloid volume in the entorhinal cortex, but not in the CA1 field and area 9, accounted for 58.5% of MMSE variability. Multivariate analyses showed that total NFT counts in the entorhinal cortex and area 9 as well as neuron numbers in the CA1 field were the best predictors of MMSE score. CONCLUSIONS: These new stereologic data indicate that neuronal pathology in hippocampal formation and frontal cortex closely reflects the progression of cognitive deficits in brain aging and AD. They also demonstrate that amyloid volume has no additional predictive value, in terms of clinicopathologic correlations, beyond its interaction with NFT.

Aged↗

Stereologic analysis of neurofibrillary tangle formation in prefrontal cortex area 9 in aging and Alzheimer's disease.

Alzheimer's disease (AD) is characterized neuropathologically by several features including extensive neuronal death in the cerebral cortex. In fact, while neuropathological changes restricted to the hippocampal formation are a consistent reflection of age-related memory impairment, overt dementia is present only in cases with neocortical involvement. Several quantitative studies have reported a substantial loss of neurons from these regions and a parallel increase in the number of neurofibrillary tangles (NFT). However, accurate quantitative data on the dynamics of NFT formation are lacking. In the present study, we performed a stereologic analysis of the proportions of intracellular and extracellular (ghost) NFT, and unaffected neurons in the deep part of layer III (layer IIIc) and the superficial part of layer V (layer Va) of Brodmann's prefrontal cortex area 9. Elderly cognitively unimpaired cases were compared with cases with different degrees of cognitive dysfunction. The data revealed differential rates of formation of intracellular and extracellular NFT between the two layers, and confirmed the presence of a severe disease-associated, but not age-related, neuronal loss. It was also shown that a susbtantial number of pyramidal cells may persist either unaffected or in a transitional stage of NFT formation in both neocortical layers. These results suggest that a considerable number of neurons containing an intracellular NFT exists in the neocortex until late in the course of AD. Whereas it is not possible to assess whether such transitional neurons are fully functional, these affected neurons might respond positively to therapeutic strategies aimed at protecting the cells that are prone to neurofibrillary degeneration in AD.

Aged↗

Stereologic assessment of the total cortical volume occupied by amyloid deposits and its relationship with cognitive status in aging and Alzheimer's disease.

Although the presence of amyloid deposits is required to establish the neuropathologic diagnosis of Alzheimer's disease, from a clinical point of view, a direct contribution of these cerebral lesions to cognitive deficits is still controversial. The development and standardization of quantitative and accurate biochemical and neuropathologic methods may be critical to improve the postmortem diagnosis and clinicopathologic correlations. Here, we used a point counting method, based on the Cavalieri principle, to estimate the volume occupied by amyloid deposits in a discrete region of the prefrontal cortex and in the hippocampal formation, in brains from patients with cognitive status ranging from normal to severely demented. We demonstrate that the assessment of the total volume occupied by the amyloid deposits in the entorhinal cortex and subiculum can be considered an effective predictor of dementia severity. We also reveal the existence of a high degree of regional and interindividual heterogeneity in amyloid distribution and relative volume. Our data suggest that even though a correlation was observed between the stereologic point counting method and a non-stereologic random field thresholding approach, in most cases non-stereologic methods may not provide adequate samples of the tissue and may lead to unreliable estimates of amyloid burden due to the inhomogeneous distribution of amyloid in the cerebral cortex and the large variability among brains.

Aged↗

Cholinergic deficits in the brains of patients with parkinsonism-dementia complex of Guam.

Patients with parkinsonism-dementia complex (PDC) of Guam showed moderate loss of choline acetyl transferase activity in the midfrontal and inferior parietal cortex, and severe loss in the superior temporal cortex. This deficit was similar to that seen in Alzheimer's disease and less severe than Lewy body disease. Thus, cholinergic deficits in the neocortex might contribute to some of the cognitive alterations in PDC of Guam.

Acetylcholine↗

Cytology of human caudomedial cingulate, retrosplenial, and caudal parahippocampal cortices.

Brodmann showed areas 26, 29, 30, 23, and 31 on the human posterior cingulate gyrus without marking sulcal areas. Histologic studies of retrosplenial areas 29 and 30 identify them on the ventral bank of the cingulate gyrus (CGv), whereas standardized atlases show area 30 on the surface of the caudomedial region. This study evaluates all areas on the CGv and caudomedial region with rigorous cytologic criteria in coronal and oblique sections Nissl stained or immunoreacted for neuron-specific nuclear binding protein and nonphosphorylated neurofilament proteins (NFP-ir). Ectosplenial area 26 has a granular layer with few large pyramidal neurons below. Lateral area 29 (29l) has a dense granular layer II-IV and undifferentiated layers V and VI. Medial area 29 (29m) has a layer III of medium and NFP-ir pyramids and a layer IV with some large, NFP-ir pyramidal neurons that distinguish it from areas 29l, 30, and 27. Although area 29m is primarily on the CGv, a terminal branch can extend onto the caudomedial lobule. Area 30 is dysgranular with a variable thickness layer IV that is interrupted by large NFP-ir neurons in layers IIIc and Va. Although area 30 does not appear on the surface of the caudomedial lobule, a terminal branch can form less that 1% of this gyrus. Area 23a is isocortex with a clear layer IV and large, NFP-ir neurons in layers IIIc and Va. Area 23b is similar to area 23a but with a thicker layer IV, more large neurons in layer Va, and a higher density of NFP-ir neurons in layer III. The caudomedial gyral surface is composed of areas 23a and 23b and a caudal extension of area 31. Although posterior area 27 and the parasubiculum are similar to rostral levels, posterior area 36' differs from rostral area 36. Subregional flat maps show that retrosplenial cortex is on the CGv, most of the surface of caudomedial cortex is areas 23a, 23b, and 31, and the retrosplenial/parahippocampal border is at the ventral edge of the splenium. Thus, Brodmann's map understates the rostral extent of retrosplenial cortex, overstates its caudoventral extent, and abridges the caudomedial extent of area 23.

Aged↗

An unusual population of pyramidal neurons in the anterior cingulate cortex of hominids contains the calcium-binding protein calretinin.

In the context of an on-going comparative analysis of primate neocortex evolution, we describe the occurrence and distribution of a previously unrecognized group of pyramidal neurons, restricted to the superficial part of layer V in the anterior cingulate cortex of hominids and characterized by immunoreactivity to the calcium-binding protein, calretinin. These neurons were rare in orangutans, more numerous in gorillas and common chimpanzees, while humans had the highest numbers. These calretinin-containing pyramidal cells were not observed in the cingulate cortex of any other primate or mammalian species. This finding, together with other recent observations on the hominoid cingulate cortex, is interesting when considering primate neocortical evolution, as it indicates possible adaptive and anatomical modifications in a cortical region critical for the integration of many aspects of autonomic function, vocalization, and cognitive processes.

Aged↗

TAU as a susceptibility gene for amyotropic lateral sclerosis-parkinsonism dementia complex of Guam.

BACKGROUND: A Guam variant of amyotrophic lateral sclerosis (ALS-G) and parkinsonism dementia complex (PDC-G) are found in the Chamorro people of Guam. Both disorders have overlapping neuropathologic findings, with neurofibrillary tangles in spinal cord and brain. The cause of ALS-G-PDC-G is unknown, although inheritance and environment appear important. Because neurofibrillary tangles containing tau protein are present in ALS-G-PDC-G, and because mutations in the tau gene (TAU) cause autosomal dominant frontotemporal dementia, TAU was examined as a candidate gene for ALS-G-PDC-G. METHODS: TAU was evaluated by DNA sequence analysis in subjects with ALS-G-PDC-G, by linkage analysis of TAU polymorphisms in an extended pedigree from the village of Umatac, and by evaluation of linkage disequilibrium with polymorphic markers flanking and within TAU. RESULTS: Linkage disequilibrium between ALS-G-PDC-G and the TAU polymorphism CA3662 was observed. For this 2-allele system, PDC and ALS cases were significantly less likely than Guamanian controls to have the 1 allele (4.9% and 2% vs 11.5%, respectively; Fisher exact P =.007). DNA sequence analysis of TAU coding regions did not demonstrate a mutation responsible for ALS-G-PDC-G. Analysis of TAU genotypes in an extended pedigree of subjects from Umatac showed obligate recombinants between TAU and ALS-G-PDC-G. Linkage analysis of the Umatac pedigree indicates that TAU is not the major gene for ALS-G-PDC-G. CONCLUSIONS: The genetic association between ALS-G-PDC-G implicates TAU in the genetic susceptibility to ALS-G-PDC-G. TAU may be a modifying gene increasing risk for ALS-G-PDC-G in the presence of another, as yet, unidentified gene.

Adult↗

Spinal cord neurofibrillary pathology in Alzheimer disease and Guam Parkinsonism-dementia complex.

We examined spinal cords of neurodegenerative disease patients and controls living on the Island of Guam and in the continental United States. These patients had pathologically confirmed parkinsonism dementia-complex (PDC) with or without amyotrophic lateral sclerosis (ALS), or Alzheimer disease (AD), respectively. Nearly all of the spinal cords examined from both groups of patients contained neurofibrillary tangles (NFT). The immunohistochemical profile of these NFTs indicates that they are composed of hyperphosphorylated tau protein like their counterparts in the brains of these patients. Western blot analysis confirmed this by revealing that sarcosyl insoluble tau in spinal cord extracts from patients with NFTs exhibited the presence of all 6 tau isoforms similar to that from AD and ALS/PDC cortical gray matter.

Aged↗

TorsinA accumulation in Lewy bodies in sporadic Parkinson's disease.

Parkinson's disease (PD) is a neurodegnerative disorder that is pathologically characterized by the presence of Lewy bodies in the brain. We show that Lewy bodies in PD are strongly immunoreactive for torsinA, the protein product of the DYT1 gene, which is associated with primary generalized dystonia. In the substantia nigra, torsinA immunoreactivity is localized to the periphery of Lewy bodies, whereas, in cortical Lewy bodies it is uniformly distributed. The significance of this finding is unknown, but may implicate torsinA in neuronal dysfunction that occurs in PD as well as in primary dystonia.

Carrier Proteins↗

The evolution of diagnosis in early Parkinson disease. Parkinson Study Group.

CONTEXT: Since there is no diagnostic biological marker for Parkinson disease (PD), the diagnosis is based on the results of clinical assessment. The accuracy of diagnosis improves with time and repeated assessments. Studies that require only inclusion of early cases of PD present a diagnostic challenge. Previous studies concluded that initial diagnoses of PD made by general neurologists were incorrect in 24% to 35% of the cases when patients were examined at autopsy. Experts in movement disorders are expected to have greater accuracy of initial diagnosis of PD. OBJECTIVE: To determine the evolution of clinical diagnosis in patients with early PD made initially by experts in PD. DESIGN: Eight hundred patients with mild parkinsonian symptoms (Hoehn and Yahr stage 1 or 2) who received a diagnosis of PD less than 5 years before the beginning of the study were included in the original Deprenyl and Tocopherol Antioxidative Therapy for Parkinson's Disease study. These patients were followed up prospectively with repeated clinical assessments. The following clinical criteria were used to reassess the initial diagnosis: investigator's confidence in the diagnosis of PD, presence of atypical clinical features, findings of imaging studies, response to levodopa, and results of autopsy examinations. RESULTS: The mean +/- SD duration of illness in the 800 cases at enrollment was 2.2+/-1.3 years, and the mean +/- SD Hoehn and Yahr stage was 1.6+/-0.5. The mean +/- SD follow-up was 6.0+/-1.4 years (range, 0.2-7.6 years). In 5 cases, PD was not confirmed at autopsy, and in 15 patients, the results of imaging studies indicated the presence of other pathological conditions. Of the 550 cases treated with levodopa, 49 (8.9%) had little or no improvement; 6 of these cases overlap with either autopsy or imaging study exclusion criteria. Two other cases had at least 4 of the 6 atypical clinical features arguing against the diagnosis of PD. Thus, of the 800 patients, 65 (8.1%) did not have PD according to the study criteria. Compared with those patients with the final diagnosis of PD, in the diagnoses of 60 patients without autopsy, the duration of symptoms (mean +/- SD, 7.2+/-2.0 years vs. 8.3+/-1.9 years; P<.001) and the duration of follow-up (5.3+/-1.6 years vs. 6.1+/-1.3 years; P<.001) were shorter. CONCLUSIONS: We found that 65 (8.1%) of patients initially diagnosed as having PD were later found to have an alternate diagnosis based on multifactorial clinical diagnostic criteria. This alternate diagnosis indicated that experts in PD changed their diagnoses infrequently during the 7.6-year follow-up.

Age of Onset↗

Contribution of Lewy body inclusions to dementia in patients with and without Alzheimer disease neuropathological conditions.

CONTEXT: Lewy bodies (LBs) are intraneuronal inclusions in the brain that have been increasingly recognized as neuropathological lesions with relevance not only to Parkinson disease but also to Alzheimer disease. However, the degree to which the density of LBs in the brain contributes to the severity of dementia has not been clear. OBJECTIVE: To determine the degree to which LB "burden" contributes to dementia. DESIGN: Brain specimens were examined from 273 consecutive autopsies of elderly subjects residing in a nursing home. The numbers and densities of LBs were determined in multiple brain regions, and their correlation with a measure of cognition and functional status (Clinical Dementia Rating) during the 6 months preceding death was determined. SETTING AND PATIENTS: Postmortem study of nursing home residents. RESULTS: The severity of dementia correlated significantly and positively with the density of LBs. These correlations were independent of other neuropathological disorders commonly associated with dementia, including Alzheimer disease. The density of LBs correlated significantly with dementia severity whether or not the diagnostic criteria for Alzheimer disease were met and after the contribution of classical Alzheimer disease lesions, neuritic plaques, and neurofibrillary tangles had been accounted for by partial correlation analysis. CONCLUSION: Lewy body inclusions appear to contribute significantly to cognitive deficits in the elderly in a manner that is independent of other neuropathological disorders. Arch Neurol. 2000;57:1145-1150

Aged↗

Parkinsonism, dementia and vertical gaze palsy in a Guamanian with atypical neuroglial degeneration.

A 58-year-old Chamorro female patient, who died in 1993, was examined clinicopathologically. At the age of 51, she suffered from hemiparkinsonism, then bradykinesia, rigidity without tremor, and dementia. Extrapyramidal symptoms developed, and at the age of 57, vertical gaze palsy was noted. The clinical diagnosis was parkinsonism-dementia complex (PDC) with vertical gaze palsy. The brain showed atrophy in the frontal and temporal lobes, and the atrophy was accentuated in the dentate gyrus, Ammon's horn and parahippocampal gyrus. The basal ganglia, thalamus and midbrain were moderately atrophic. The substantia nigra and locus ceruleus were completely depigmented. Numerous neurofibrillary tangles (NFTs) were seen in the subiculum and amygdaloid nucleus. Many NFTs were evident in the parahippocampal gyrus, lateral occipitotemporal gyrus, insula, Sommer sector, basal nucleus of Meynert, lateral nucleus of the thalamus, subthalamic nucleus and brain stem, and several were observed in the globus pallidus and hypothalamus. The Sommer sector, substantia nigra, locus ceruleus and basal nucleus of Meynert showed severe loss of neurons, and a moderate loss of neurons was exhibited by the globus pallidus. These findings were apparently consistent with those associated with PDC. However, in this patient, severe neuronal loss was seen in the subthalamic nucleus and lateral nucleus of the thalamus, and grumose degeneration, which has not previously been reported in PDC, was seen in the dentate nucleus. In addition, many tufted astrocytes, which have been reported to occur in progressive supranuclear palsy (PSP) and postencephalitic parkinsonism, but scarcely observed in PDC, were present. Furthermore, astrocytic plaques, which have been considered as a specific finding of corticobasal degeneration (CBD), were observed in the cerebral cortex. On the other hand, granular hazy astrocytic inclusions, previously reported to occur in PDC, were not seen. Chromatolytic neurons were not observed. The question thus arises as to whether it is appropriate to consider this patient as having suffered from a combination of PDC, PSP and CBD. From the view points of absence of granular hazy astrocytic inclusions and chromatolytic neurons, and of tufted astrocytes in the neostriatum, it is conceivable that this patient is a case of a new disease entity.

Brain↗