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C Q Mountjoy

Publications and source records attributed to C Q Mountjoy.

61 records · Page 4Linked to original sources
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Neurofibrillary degeneration and neuronal loss in Alzheimer's disease.

Neuronal loss in Alzheimer's disease, especially in cerebral cortex and hippocampus, appears closely associated with the process of neurofibrillary degeneration. In certain noncortical nuclei neuronal loss appears not to depend upon the formation of neurofibrillary tangles. Neurofibrillary tangles and neurons were counted in the same populations of neurons in five brain regions. In the locus ceruleus and nucleus basalis, where tangles have a loose or globose structure, correlations with neuronal counts were not significant. In cerebral cortex and hippocampus, tangles have a more dense and often a flame-like appearance and their correlations with neuronal counts were significant. The relationships between tangles and noncortical neurons reported here suggest that the appearance of tangles does not necessarily herald the demise of a neuron in Alzheimer's disease. It can be reasonably anticipated that these relationships depend upon the clinical heterogeneity of Alzheimer's disease, regional differences in the brain and/or the macromolecular composition of neurofibrillary tangles.

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PubMedDate not supplied

Changes in intraneuronal lipopigment in Alzheimer's disease.

Brains were examined from 22 patients with Alzheimer's disease (AD) (mean age 80.5, S.D. 11.5) and were compared with brains from 20 nondiseased subjects (mean age 81.1, S.D. 10.2). Intraneuronal lipopigment in all layers of a region of the superior frontal cortex was identified by fluorescence microscopy. The areas enclosed by the outlines of discrete regions of lipopigment autofluorescence were measured and assigned to a range of size categories. AD was associated with significant (p less than 0.05) decreases in the mean number (per neuron) of discrete regions of yellow lipopigment autofluorescence in the three smallest size categories and a significant increase in one of the larger size categories. Also, AD was associated with a significant decrease in the mean number (per neuron) of discrete regions of lipopigment autofluorescence (p less than 0.001). Significant (p less than 0.05) correlations were obtained between the Blessed dementia score (obtained within 2 years of death) and these lipopigment variables. The changes in neuronal lipopigment in AD may reflect an increased rate of lipopigment formation related to membrane and lysosomal abnormalities.

Aged↗
PubMedDate not supplied

Automated differential cell counting on a sector of the normal human hippocampus: the influence of age.

The neurons and the glia of the human hippocampus are notoriously vulnerable in various pathological conditions including those linked to ageing. There may even be differences between the young and the old in the absence of manifest disease. Using an image analyser, systematic measurements of cell numbers in the region of the Sommer (Hl) sector of the human hippocampus have been made on post-mortem tissue from thirty-seven female and forty-nine male subjects aged between 15 and 96 years. In fifteen male and fifteen female subjects both hemispheres were available for analysis so that measurements were made on a total of 116 hemispheres. For each specimen the fresh volume of the hemisphere was measured and corrections subsequently made for changes in size which occurred during fixation, processing, mounting and staining. After all the correction factors had been applied the number of nucleolated neurons was found to fall by about 3.6% per decade (P less than 0.0001). There was no significant age-related change in the number of glia. Marked individual variations were found.

Adolescent↗
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Validation of the full and short forms of the CAMDEX interview for diagnosing dementia. Cambridge Examination for Mental Disorders of the Elderly.

The present study compares the sensitivity and specificity of the short and full forms of the Cambridge Examination for Mental Disorders of the Elderly (CAMDEX) interview in diagnosing dementia. We tested 73 subjects meeting DSM-IIIR criteria for dementia and 61 matched controls. The short version was applied 3 months after the full one to guarantee a relative stability of the tested functions. Referred to an independent clinical rating made at the beginning of the study, the levels of sensitivity and specificity were not significantly different in the two forms and fully comparable with those of the original full English version. Moreover, the scores on analogous sections of the two versions were highly correlated in the demented and control groups. These findings support the hypothesis that the short form of the CAMDEX maintains the psychometric properties of the full one, and consequently can be used in diagnostic routines for a variety of clinical and research purposes.

Dementia↗
PubMedDate not supplied

Alzheimer's disease: distribution of changes in intraneuronal lipopigment in the frontal cortex.

Brains from 22 patients with Alzheimer's disease (AD) and 20 non-diseased subjects were examined. Intraneuronal lipopigment in 2,440 nucleolated neurons throughout the depth of cortex was identified by fluorescence microscopy. In the AD brains, the mean total area per neuron of the outlines of lipopigment was significantly increased in the region adjacent to the brain surface (sixths 1-3), and analysis of variance showed a significant interaction between depth of cortex (in sixths) and AD for this lipopigment variable (p = 0.012). After relating this lipopigment variable to the size of neuronal bodies, the results indicate that this change occurs in pyramidal neurons, although other neuronal types may also be affected. At least one of three AD-related changes in lipopigment was found in each sixth of the depth of cortex.

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