摘要:

The two major primary degenerative dementias, dementia of Alzheimer type (DAT) and frontal lobe degeneration of non-Alzheimer type (FLD) have several clinical features in common but also many symptoms that differ. In a clinical material of 80 patients with either of the two forms of dementia (DAT = 39, FLD = 41) we have studied the levels of neuropeptides in the cerebrospinal fluid (CSF) in order to find biochemical markers for CNS affection. The dementia forms were evaluated by careful clinical analysis, psychometric testing and measurement of regional cerebral blood flow. Approximately one third of the subjects died during the completion of the study and neuropathology was performed, confirming the diagnoses. We observed reductions in the CSF levels of antidiuretic hormone and somatostatin in both DAT and FLD. A strong tendency to reduction was noted for neuropeptide Y (NPY). There was a correlation with the duration of disease demonstrating a significant reduction in NPY levels in subjects with DAT. Most notably there was a strong reduction in the levels of delta sleep inducing peptide (DSIP) in DAT cases only. The levels of DSIP in FLD were the same as in controls. The reverse was found for corticotropin releasing factor (CRF) which had a significant reduction in FLD patients but not in those with DAT. The present study indicates a difference in the CSF levels of neuropeptides, observations that these may serve as biochemical markers which differentiate DAT and FLD.

ISSN:1420-8008    

DOI:10.1159/000107318

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Non-Alzheimer''s dementia due to lobar atrophy had choline acetyltransferase activities comparable with control rather than Alzheimer''s disease values, based on 3 autopsy proven cases on Pick''s disease and biopsies from 3 examples of dementia of frontal lobe type. Muscarinic cholinergic receptors were relatively spared only in Alzheimer''s disease. Serotonin receptors were markedly reduced (based on Pick cases) whereas measures that reflected presynaptic serotonergic activity were either not affected or increased. Cerebrospinal fluid and brain tissue measurements suggested that inhibitory interneurones and dopamine release were relatively spared. There was no in vitro evidence of hypometabolism.

ISSN:1420-8008    

DOI:10.1159/000107319

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Molecular genetics has led to considerable advances in our understanding of the transmissible spongiform encephalopathies. The identification of pathogenic mutations in the prion protein gene has enabled a molecular reclassification of the familial forms of these diseases, which may now be referred to as inherited prion diseases. Prion diseases of both humans and animals are associated with deposition of an abnormal isoform of a host-encoded protein, the prion protein (PrP). Human prion diseases have inherited, sporadic and acquired forms. A considerable body of evidence now supports the idea that the transmissible agent in these diseases may be an abnormal isoform of the prion protein. The identification of pathogenic mutations in the PrP gene has enabled the identification of cases of inherited prion disease that would not have been recognised using existing clinical and pathological diagnostic criteria. Since marked clinical and neuropathological overlap between the different neurodegenerative disorders is well recognised, PrP gene analysis is of increasing importance in differential diagnosis. Frontal lobe dementia of non-Alzheimer type and Pick''s disease share a number of important clinical and pathological features with prion diseases, and could be considered as candidate prion diseases. However, we have not been able to demonstrate either PrP mutations or the presence of the disease-associated isoform of prion protein in several well-characterised families with these disorders.

ISSN:1420-8008    

DOI:10.1159/000107320

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Twenty-five out of 26 cases of autopsy-verified frontal lobe degeneration of non-Alzheimer type (FLD) were found to have focal frontal or frontotemporal blood flow reductions involving both hemispheres. The deviant case had an asymmetric frontal pathology only apparent on the right side. Focal reduction of blood flow in the frontal lobes is, however, a common and unspecific flow abnormality found in e.g. Pick''s disease, Creutzfeldt-Jakob''s disease, and in some cases of Alzheimer''s disease. Low frontal flow has also been reported in schizophrenia and in toxic encephalopathy. Since a characteristic feature of FLD is a steady progress of the pathology, serial flow measurements extending over several years are especially informative.

ISSN:1420-8008    

DOI:10.1159/000107321

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The present study examined the utility of the Word Fluency Test (WFT) as a frontal-lobe-activating test in brain imaging. Regional cerebral blood flow (rCBF) was measured during rest and during the WFT in 49 healthy volunteers and in 15 patients with frontal lobe dementia (FLD). The results showed a highly significant frontal lobe activation in 85% of the normal subjects. This finding was not related to age or to the level of performance on the WFT. A significant frontal activation was seen in 13 of the 15 FLD patients. The frontal flow increase did not reach normal levels, and was not related to age, illness duration or severity of clinical symptoms. The results suggest that the WFT is an ideal test to use in conjunction with functional imaging in normals as well as in patients with organic dementia.

ISSN:1420-8008    

DOI:10.1159/000107322

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

A 58-year-old man developed progressive difficulty with comprehension and verbal output with dementia. Positron emission tomography with 18F 2-fluoro-2-deoxy-D-glucose demonstrated asymmetrical frontal and anterior temporal lobe loss of glucose use. Scopolamine infusion (0.3 mg) did not influence memory. Postmortem studies revealed evidence of Pick''s disease, with Pick bodies, loss of somatostatin, preservation of choline acetyltransferase and immunostaining with neurofilament antibodies. Pharmacological challenge and positron imaging offer valuable means for the noninvasive assessment of dementing illness. The contributions of functional imaging to our knowledge of frontal involvement in dementing illness are reviewed.

ISSN:1420-8008    

DOI:10.1159/000107323

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The behavioral, neuropsychological and single photon emission computerized tomography characteristics of 5 patients with progressive degeneration of the right hemisphere are described. In all, the brain regions with greatest involvement were right-frontal and temporal. Psychosis, compulsions and behavioral disinhibition were the dominant, and often first, symptoms. Affect was flattened and the patients seemed distant and remote. Neuropsychological testing did not reveal a consistent pattern that helped localize the abnormality to the right frontotemporal region. These patients contrast dramatically to those with left frontotemporal degeneration in whom behavior and psychiatric status is often normal. This study suggests that the right hemisphere may be primary for the control of social conduct.

ISSN:1420-8008    

DOI:10.1159/000107324

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Neuropsychological investigations were performed on 18 patients with a clinical diagnosis of frontal lobe dementia supported by regional cerebral blood flow measurements. Nature and degree of cognitive impairment were examined with a comprehensive test battery. The results of the neuropsychological assessment could be described as three levels of cognitive impairment. The increasing levels of cognitive impairment were accompanied by corresponding levels of reduced cerebral blood flow in frontotemporal areas. No apparent relationship emerged between impairment level and illness duration, indicating a considerable individual variation in the clinical course of frontal lobe dementia.

ISSN:1420-8008    

DOI:10.1159/000107325

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The quality of the neuropsychological investigation of behavioural changes in frontal dementias is dependent on the specificity of the behavioural analyses. A review of methodological issues and published findings identifies possible potential reasons for misinterpretation of research neuropsychological data in these studies. The areas reviewed include the operational definitions of terms such as ''frontal lobes'' and ''frontal functions''; identification of experimental limitations in frontal lobe research; and highlights of neuropsychological investigations of frontal lobe functions. These deliberations suggest a practical approach to the behavioural assessment of frontal dementias.

ISSN:1420-8008    

DOI:10.1159/000107326

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The patterns of language disorder associated with ''progressive aphasia'' due to lobar atrophy were compared with the language dysfunction of patients with dementia of frontal lobe type (DFT). The progressive aphasias were characterised primarily by impairment at the structural levels of language: phonology, grammar and semantics, whereas DFT was associated primarily with aspontaneity and loss of generative capability. However, there was overlap in language symptomatology, particularly with progression of disease. The findings lend support to the argument that progressive aphasia and DFT represent different clinical manifestations of a common pathology, and form part of the spectrum of lobar atrophies.

ISSN:1420-8008    

DOI:10.1159/000107327

出版商:S. Karger AG    

年代:1993

数据来源: Karger