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Biomedical subjects

J H Morris

Publications and source records attributed to J H Morris.

65 records · Page 4Linked to original sources
PubMed1965

Susceptibility of the gibbon Hylobates lar to falciparum malaria.

The splenectomnized juvenile gibbon, Hylobates lar, is susceptible to infection with trophozoites of Plasmodium falciparum. All subjects in a group of six animals that were injected with freshly collected blood from four infected humans in Saraburi Province, Thailand, developed parasitemia 2 to 20 days later; infections were transmitted from one of these subjects to three clean gibbons.

Animals↗
PubMedDate not supplied

Accuracy of clinical operational diagnostic criteria for Alzheimer's disease in relation to different pathological diagnostic protocols.

In this study we analysed the accuracy of two sets of clinical diagnostic criteria, the NINCDS/ADRDA and DSM-III-R, in relation to the currently used pathological diagnostic criteria for Alzheimer's disease (AD), the Khachaturian criteria, the Tierney A3 criteria and the CERAD protocol. The sensitivity of the individual clinical diagnostic criteria, NINCDS/ADRDA and DSM-III-R, is poor (34-58%) irrespective of the pathological diagnostic criteria applied for the definite diagnosis of AD. The combination of the NINCDS/ ADRDA 'possible' and 'probable dementia of the Alzheimer type' (DAT) categories has a high sensitivity (91-98%). However the combination resulted in very poor specificity (40-61 %). Thus, none of the clinical diagnostic criteria is satisfactory. We found similar results when we analysed the predictive value of these clinical diagnostic criteria. The positive predictive value of NINCDS 'probable DAT' category and that of the DAT diagnosis by DSM-III-R is very high (89-100%). This makes the use of these categories suitable for research purposes. However, the negative predictive value of both diagnoses is poor (33-63%), making these criteria unsuitable for diagnostic purposes in clinical practice.

Aged↗
PubMedDate not supplied

Hippocampal pathology reflects memory deficit and brain imaging measurements in Alzheimer's disease: clinicopathologic correlations using three sets of pathologic diagnostic criteria.

Neurofibrillary tangles (NFT), neuritic plaques and amyloid load were quantified in sections of the hippocampus at the level of the lateral geniculate body in 41 consecutive cases fulfilling pathological criteria for diagnosis of Alzheimer's disease (AD) and coming to autopsy after longitudinal study during life. A strong correlation was found between NFT density in the hippocampus and cognitive impairment scores obtained shortly before death, particularly with scores of memory impairment. Weaker and less consistent correlations were found for hippocampal neuritic plaques and amyloid load with cognitive/memory deficits. No significant correlations were found between hippocampal pathology and either age of onset or disease duration. All three measures of hippocampal pathology were inversely correlated with the minimum medial temporal lobe (MTL) width, a measure of the MTL atrophy made from temporal-lobe-oriented X-ray computed tomography scans performed during life; the strongest correlation being between atrophy of the MTL and NFT density in the hippocampus.

Alzheimer Disease↗
PubMedDate not supplied

Clustering of pathological features in Alzheimer's disease: clinical and neuroanatomical aspects.

We have analyzed the tendency of amyloid load, neuritic plaques and neurofibrillary tangles (NFT) in the hippocampus and neocortex to occur in clusters in 49 consecutive cases of Alzheimer's disease (AD). This clustering tendency of the pathology was analysed in relation to severity of clinical disease assessed within 6 months before death, duration and age at onset of disease and at death. Amyloid plaques showed only a slight tendency to cluster together while neuritic plaques and, even more, NFT were clearly clustered. A greater clustering tendency was associated with more severe clinical impairment with particularly strong correlations being found between the clustering tendency of NFT in the hippocampus and clinical memory deficit, and between the clustering tendency of NFT in the parietal neocortex and overall cognitive deficit. Neuritic plaques showed similar but less pronounced and robust correlations between clustering and cognitive status. In the hippocampus NFT clustering was also negatively correlated with age at death, but not duration of disease nor age of disease onset. We conclude that clustering characterises neuritic pathology but not diffuse amyloid deposits and significantly affects cognition. The discrepancies between the group diagnosed as AD-only and the patient group that contained all patients, including the ones with mixed pathology, lead us to believe that any additional pathology might have a significant effect on the cognitive status of AD patients.

Alzheimer Disease↗
PubMedDate not supplied

Relative roles of plaques and tangles in the dementia of Alzheimer's disease: correlations using three sets of neuropathological criteria.

We have performed a quantitative analysis of the amyloid load (plaques), neuritic plaques and neurofibrillary tangles (NFT) in the frontal, temporal and parietal association cortices of autopsied brains from 49 prospectively evaluated patients with Alzheimer's disease (AD) diagnosed according to three sets of published pathological criteria. These patients had been assessed clinically with psychological testing of cognitive abilities within 6 months of death. Correlations were sought between severity of pathological change and cognitive status before death, duration of disease and age at death. Using Khachaturian and CERAD criteria highly positive correlations were obtained between the extent of cognitive deficit and the density of NFT in frontal and parietal lobes. The percentage area of cortex occupied by amyloid in the parietal lobe was correlated to the cognitive deficit only in the CERAD-diagnosed cases. The density of all amyloid plaques (AP) showed no correlation with the extent of cognitive deficit, but the densities of neuritic plaques did correlate with cognitive deficit. Both amyloid load and tangle densities were positively correlated with disease duration. All these correlations were reduced or absent in a subgroup of cases fulfilling the Tierney et al. A3 diagnostic criteria for AD. We found no pathological measure that correlated with the age of patients at death. Amyloid loads and NFT densities showed highly significant but selective positive correlations, the most striking being between temporal lobe NFT density and frontal and parietal lobe amyloid load and between temporal lobe NFT density and frontal and parietal lobe NFT densities. Correlations involving AP density as a measure of amyloid load were almost always less significant than those involving the percentage area of cortex occupied by amyloid, suggesting that the latter measures amyloid load more accurately. However, the highest correlations of NFT densities were with neuritic plaque densities. Overall this study highlights the relevance of neuritic changes (revealed by NFT and neuritic plaques) and the irrelevance of amyloid plaques to the dementia of AD.

Aged↗
PubMedDate not supplied

Unusual CT patterns of multiple sclerosis.

In three patients with histologically confirmed, acute demyelinating disease (multiple sclerosis), serial cranial computed tomography revealed unusual findings. Computed tomography showed contrast-enhancing lesions with mass effect, which suggested brain tumors and the need for surgical biopsy. Steroids were administered to each patients; in two, the large mass lesions resolved dramatically. These and other rapid changes may help in the recognition of multiple sclerosis.

Adult↗