Familial prion disease in a Hungarian family with a novel 144-base pair insertion in the prion protein gene.

About 15% of human prion diseases are inherited, and are associated with point or insertional mutations of the prion protein gene (PRNP). Four families with six octapeptide repeat insertions (OPRI) in the PRNP gene have been described in the literature so far. Here we report two cases in a Hungarian family with a new six OPRI (R1R2R2R3R2R3gR3R2R2R3R4) in the PRNP gene. The clinical features (progressive ataxia, dementia and anosmia), the age of onset and the duration of disease were almost identical. In addition to the cerebellar and parahippocampal pathological changes already described, we also found deposits of pathological prion protein in the olfactory system.

New observation on ubiquitinated neurons in the cerebral cortex of multiple system atrophy (MSA).

To investigate neuronal damage in the cerebral cortex in patients with multiple system atrophy (MSA), immunohistochemical stainings were carried out on the prefrontal cortex, the hippocampus, the precentral gyrus, the supplementary motor cortex and the occipital cortex in 6 cases of MSA and 6 controls, using antibodies against ubiquitin, tau protein and neurofilaments (BF10, RT97, 147). In MSA cases, a variable number of neuronal ubiquitinated inclusions were observed in the granule cell layer of the dentate gyrus (3/6) and the prefrontal cortex (3/6). An increased number of ubiquitinated dots-like structures were also observed in the parahippocampal gyrus of MSA cases (4/6) in comparison with controls. These results showed further evidence of neuronal damage in the cerebral cortex in MSA and strongly suggest a relationship between the cerebral cortical pathology and occasional manifestation of cognitive deficits in some MSA cases.

Accumulation of tubular structures in oligodendroglial and neuronal cells as the basic alteration in multiple system atrophy.

In 8 brains of patients with various combinations of striatonigral degeneration, olivopontocerebellar atrophy and Shy-Drager syndrome, inclusion bodies were demonstrated in the cytoplasm and nucleus of both neuronal and oligodendroglial cells and in neuronal processes by means of silver staining, immunocytochemistry and electron microscopy. Differing from oligodendroglial cytoplasmic inclusions recognized by anti-ubiquitin, anti-alpha- and anti-beta-tubulin, and anti-tau antibodies, neuronal cytoplasmic inclusions were stained only by anti-ubiquitin antibody but not with those raised against cytoskeletal proteins. Tubular structures forming the inclusion bodies irrespective of their glial or neuronal location, have fuzzy cover and side extensions which make them similar to the linear structures described in motor neuron diseases. Our study proves that the accumulation of abnormal tubular structures in both oligodendrocytes and neurons is the basic pathological alteration in multiple system atrophy and defines multiple system atrophy as a group of diseases with similar cellular pathology or as a nosological entity.

The vasculature of experimental brain tumours. Part 3. Permeability studies.

The aim of this work was to elucidate the direction and time-course of transport processes which may affect the accumulation of oedema associated with experimental brain tumours. Astrocytomas were produced in BD-IX rats by intracerebral injection of cultured neoplastic glial cells. The cell line used was cloned from a culture of a primary mixed glioma induced by transplacental administration of N-ethyl-N-nitrosourea (ENU). At various times after cell injection the protein tracer horseradish peroxidase (HRP) was given to tumour-bearing rats, either intravenously or into the lateral ventricles of the brain. The movement of the HRP into tumours and surrounding brain either from blood or from ventricular cerebrospinal fluid (CSF) was studied by light and electron microscopy at various intervals after the injection of the tracer. The time-course of subsequent clearance of the HRP from the tumours and surrounding brain was also investigated. After intravenous injection, HRP rapidly penetrated all vascularized tumours and became evenly distributed within 10-20 min. The HRP remained present in sufficient quantity within the tumours to maintain this intensity for several hours, after which it gradually disappeared, showing no reaction product after 12 h. After intraventricular injection, HRP penetrated periventricular brain tissue up to a maximal distance 1-2 mm within 2 min, and the reaction product remained visible in this region for at least 20 min. In all tumour-bearing animals, HRP penetrated further into periventricular tumour tissue than into adjacent brain tissue. In large tumours HRP reaction product was seen up to 7 mm from the ventricular ependymal lining, although permeation to this distance took up to 10 min.

Glial cytoplasmic inclusions in the CNS of patients with multiple system atrophy (striatonigral degeneration, olivopontocerebellar atrophy and Shy-Drager syndrome).

Glial cytoplasmic inclusions (GCIs) were demonstrated by silver staining, immunocytochemistry and by electron microscopy in the central nervous system (CNS) of 11 patients with various combinations of striatonigral degeneration, olivopontocerebellar atrophy and Shy-Drager syndrome. Although their configuration in light microscope can sometimes resemble neurofibrillary tangles, their cellular localisation, measurements, ultrastructure, immunocytochemical characteristics and regional distribution all differ from these Alzheimer type changes. The majority of GCIs were localized in the white matter and appeared to be accompanied by an increase in the number of interfascicular oligodendroglial cells and pallor or loss of myelin staining. Our histological, ultrastructural and immunocytochemical findings all indicate that the cells which contain GCIs are oligodendrocytes and the inclusions themselves are composed of tubular structures. The presence of the until now unknown GCIs in all the 11 CNS, but not in age- and sex-matched control brains, indicates that GCI is a cellular change characteristic of multiple system atrophy and the three syndromes are various manifestations of the same disease.

The distribution of oligodendroglial inclusions in multiple system atrophy and its relevance to clinical symptomatology.

In this study a semiquantitative mapping of oligodendroglial cytoplasmic inclusions (GCIs), a feature of oligodendroglial degeneration in multiple system atrophy (MSA), was undertaken by means of a sensitive silver technique in 14 brains and 11 spinal cords of patients with various combinations of striatonigral degeneration, olivopontocerebellar atrophy and autonomic failure. The results show a system-bound extensive degeneration of interfascicular, perineuronal and perivascular oligodendrocytes. Oligodendroglial cytoplasmic inclusion-rich structures occur in the supra-segmental motor systems (primary motor and higher motor areas of cerebral cortex, 'pyramidal', 'extrapyramidal' and cortico-cerebellar systems), in the supraspinal autonomic systems and in their targets. In contrast, the visual and auditory pathways, olfactory structures, somatosensory systems, association and limbic cortical areas and subcortical limbic structures contain no or only a few GCIs. Comparison of the severity of oligodendroglial degeneration (GCI-density) with that of the neuronal alterations (neuronal cytoplasmic and nuclear inclusions, degenerated neuronal processes and loss of nerve cells) indicates a striking preponderance of oligodendroglial degeneration and that degeneration neither of axons, nor of neuronal cell bodies is a prerequisite of the development of GCIs. It also suggests that inclusion-bearing oligodendroglial degeneration may cause or contribute to the manifestation of clinical symptomatology in structures with GCI accumulation but without convincing neuronal alterations, i.e. cerebral motor cortical areas and reticular formation of the lower brainstem, both previously thought to be spared in MSA.