Cerebral cortex dendritic degeneration in subacute sclerosing panencephalitis (SSPE)

Morphometric study of the frontal cortex in subacute sclerosing panencephalitis

In biopsic material collected from the frontal cortex of 6 patients with subacute sclerosing panencephalitis (SSPE) and 5 patients with posterior fossa tumors, we estimated the neuronal and synaptic numerical densities as well as the mean volume of the neurons from layers II and III. The thickness of these layers was also determined. The evaluation of the layer's thickness suggested that there was no difference in the shrinkage in SSPE as compared to controls. No differences were found between the neuronal numerical densities and the neuronal soma sizes from SSPE and controls. Conversely the synaptic numerical density was reduced in SSPE. Given the maintenance of the neuronal numerical density in the frontal cortex of patients with SSPE, the presence of a decreased density of synapses must be regarded as a consequence of the dendritic and axonal degeneration that we previously described in this condition. It must then be borne in mind that SSPE's functional and behavioral changes might spring from alterations of the frontal cortex neuronal circuitry.

Dendritic pathology: an overview of Golgi studies in man

Study of dendritic morphology through Golgi impregnation techniques has significantly furthered our understanding of neuronal development, maturation, and senescence. It has also provided insight into the pathogenesis of a wide spectrum of disease processes ranging from brain malformations to degenerative disorders. Golgi impregnation remains virtually the only method for demonstrating dendritic morphology. It delineates the profile of the individual neuron and its dendritic ramifications with unsurpassed clarity. Although it has been widely applied to experimental neuroscience involving animal tissue, its application to human material has been limited. This review summarizes the information on dendritic development and pathology in the human brain revealed by the use of the Golgi method.

Alzheimer's disease: maintenance of neuronal and synaptic densities in frontal cortical layers II and III

Neuronal loss and alterations of the cortical neuropil were previously described on necropsic material from patients with senile dementia of the Alzheimer type, and the results compared to age-matched case controls. In frontal cortex biopsic material from our patients with Alzheimer's disease, the numerical densities of neurons and synapses were not significantly different from controls, indicating that changes in the highest cognitive functions might not depend on a generalized loss of neurons and synapses and that quantitative morphological differences may exist between Alzheimer's disease and senile dementia of the Alzheimer type.

Double infection of the CNS with herpes simplex and mumps viruses. Serological and ultrastructural studies

Clinical, serological and ultrastructural features are described in a case of acute encephalitis. The ultrastructural study of brain biopsy specimens revealed herpes-and paramyxovirus-like particles in neurons and glial cells that were characterized as herpes simplex and mumps viruses by serological study in serum and CSF. Of the few cases previously reported with double encephalitis, this is the only one in which ultrastructural and serological evidence of combined brain infection has been found.

Mitochondrial abnormalities in cortical dendrites from patients with early forms of subacute sclerosing panencephalitis (SSPE)

Biopsy fragments from the frontal cortex of two patients with early forms of subacute sclerosing panencephalitis (SSPE) were studied with ultrastructural methods. Special attention was given to mitochondrial abnormalities observed in dendrites from the three superficial cortical layers. Some of the mitochondria presented atypical elongated cristae parallel to the longer axis of the organelle and closely opposite each other. The surface of these cristae is undulated, and the intracristal space is regularly septate. As these abnormal mitochondria appeared in dendrites, which in later stages of the disease are supposed to degenerate, it is advanced that these abnormalities could be precursors of dendritic changes and be possibly related to the precocious, insidious mental changes which characterize the early forms of the disease, as it is known that the disruption of the dendritic domain is linked with neuronal dysfunction.

Cerebellar cortex ultrastructure in ataxia-telangiectasia

An ultrastructural study of a biopsy fragment from the cerebellar cortex of a patient with ataxia-telangiectasia was performed. There was a sharp reduction in the number of Purkinje cells and an increase in the number of Golgi epithelial cells. Despite the degeneration of Purkinje cell dendrites, the volumetric density of parallel fiber varicosities and the number of synapses in the molecular layer were only slightly reduced. No qualitative nor quantitative abnormalities were noted in the granular layer. An analysis is made of the severe changes in cerebellar circuitry of this patient and their probable functional implications.

Evoked potentials in the diagnosis of multiple sclerosis: a follow up study

Visual, somatosensory and brain stem auditory evoked potentials were recorded in 84 patients in whom the diagnosis of multiple sclerosis was under consideration. The patients were followed up for a maximum of 38 months or until a definite diagnosis of multiple sclerosis or of some other condition was established. Seven patients were found not to have multiple sclerosis. Abnormal evoked potentials indicating clinically silent lesions were found at the initial investigation in fourteen of the twenty-eight patients in whom a diagnosis of clinically definite multiple sclerosis was accepted during the period of follow up. In the thirty-seven patients in whom no change in clinical category occurred during the period such abnormalities were found in five. The visual evoked potential was found to be of greatest predictive value.

Preferential vulnerability of dendrites to lithium ion in rat brain and in nerve cell culture

Preferential swelling and vacuolation of dendrites were observed electron microscopically in different brain regions of rats treated with LiCl in a dose of 6-18 mmol/kg for 1-6 days. The most severe fine structural changes were revealed in the hippocampus. Low-dose (0.33 mmol/kg) lithium treatment lasting for a year did not cause any morphologically detectable alterations in the rat brain. In vitro studies showed a reduction of dendro-axonal process network of neurons measured by morphometric means after lithium exposure. Using different cultures of neuronal and glial cell populations, higher lithium uptake was observed for neuron-enriched cultures.

Dendritic abnormalities in patients with subacute sclerosing panencephalitis (SSPE). A Golgi study

Golgi studies of three cortical biopsies from patients with SSPE reveal an abnormal pyramidal dendritic domain, spine-loss, and reactive gliosis. These findings support results obtained in a previous ultrastructural study of this disease, and are in keeping with the pathological features observed in other situations in which mental changes occur.

Neurofibrillary changes in the cerebral cortex of a patient with subacute sclerosing panencephalitis (SSPE)

Biopsy fragments from the frontal cortex of one patient with SSPE were studied with ultrastructural methods. Special attention was given to the presence of neurofibrillary tangles observed in all cortical layers. These tangles were composed either of filaments with a diameter of 10 -- 12 nm or of paired helical filaments 22 -- 24 nm at their widest and periodically reduced to 10 nm about every 80 nm. These tangles were observed in all cortical layers, while those formed by single filaments were only visualized in layer 3. The simultaneous appearance of both types of tangles in the same patient suggests that they may be chemically related, which is in keeping with recent chemical data concerning the nature of the neurofilament protein subunit.