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H Leitner

Publications and source records attributed to H Leitner.

79 records · Page 5Linked to original sources
PubMedDate not supplied

On the relationship between measles virus and Alzheimer neurofibrillary tangles in subacute sclerosing panencephalitis.

We have studied the relationship between measles virus and the accumulation of abnormally phosphorylated tau (PHF-tau) in nine cases of subacute sclerosing panencephalitis (SSPE). By assessing the presence of viral intranuclear inclusions and neurofibrillary tangles (NFT) in each case, we found no correlation between presence and amount of measles virus and the numbers of neurons containing PHF-tau. Immunohistochemical double labeling in a case with long duration of disease and severe histopathologic change revealed no strict colocalization of measles virus antigen and PHF-tau throughout different brain regions. In areas containing both antigens, most neurons carrying measles virus did not have a tangle and vice versa, eventhough some colocalization beyond that expected by chance was observed in specific cortical areas. These results indicate that, although secondary to viral infection, NFT formation in SSPE is not restricted to cells carrying viral antigen. Conversely, measles virus infected cells do not necessarily accumulate PHF-tau. This lack of colocalization at the cellular level, throughout different brain areas and among different cases suggests that the formation of NFT in SSPE is not directly induced by the infectious agent. The formation of NFT in this disease appears to be elicited through a specific type of tissue damage and, thus, to be an epiphenomenon. This pathogenetic detail may be of interest for our understanding of the role of neurofibrillary degeneration in the pathogenesis of other more frequent neurodegenerative diseases with cytoskeletal pathology.

Adolescent↗
PubMedDate not supplied

GIS-based measures of environmental equity: exploring their sensitivity and significance.

In order to determine whether principles of environmental justice have been violated, a large number of empirical studies have been carried out to ascertain whether minority and low-income populations are disproportionately exposed to industrial pollution. This study provides a comparative evaluation of two commonly employed proximity measures in GIS-based environmental equity assessment, examining their influence on the results of the analysis, and proposes a methodology for evaluating the significance of these results. 1990 census data on population characteristics and data from the 1995 EPA's toxic release inventory (TRI) for the City of Minneapolis, MN are used. These results also allow a preliminary assessment of environmental equity/inequity in potential exposure to airborne toxic chemicals for racial minorities, poor people and children in Minneapolis. In the third part of the paper we develop and employ a geographic randomization methodology for assessing the significance of these results.

Adult↗
PubMedDate not supplied

Relations between electric response audiometry, conventional audiometry and psychodiagnostic examinations in hearing-impaired children.

To obtain a more objective determination of the hearing loss and thereby a more effective therapy, we compared the results of conventional audiometry (reflex and behavioural audiometry) with electric response audiometry (ERA) results in 522 children whose median age was 3 years. ERA threshold was more sensitive at 10.8 +/- 17.5 dB. The mean difference and its standard deviation are both much greater for the younger children and particularly for non-cooperative children, but neither relates clearly to intelligence. In the case of 'difficult-to-test' children (due to behavioural disturbance, mental retardation or brain damage), we carried out a psychological examination consisting of several special non-verbal tests. 62.7% of children with IQs under 70 needed sedation; for the children whose IQs lay above 70, this proportion was only 37.3%. Our artefact rejection system greatly reduced the percentage of sedations required, particularly for children under 3 years of age.

Age Factors↗