The cellular pathology of Menkes steely hair syndrome

The principal neuropathologic abnormality observed in three autopsy cases of Menkes steely hair syndrome was widespread nerve cell loss and gliosis, especially severe in the cerebral and cerebellar cortex and in the relay nuclei of the thalamus. Granular stellate cells of neocortical layer IV and the granule cells of the cerebellum are cell classes which were particularly severely depopulated. The degree of reduction of myelinated axons is consistent with axonal degeneration secondary to nerve cell loss. There are also prominent abnormalities in the patterns of dendritic arborization of surviving cortical pyramids and cerebellar Purkinje cells as seen in Golgi impregnations. The deviant neuronal forms are probably due, in part, to failure of innervation by afferent fiber systems during the fetal as well as postnatal epochs.

The Golgi rapid method in clinical neuropathology: the morphologic consequences of suboptimal fixation

Cytologic changes in neurons of the neocortex of mice consequent to suboptimal fixation have been investigated systematically in Golgi-rapid preparations. With few exceptions, there is no alteration in cellular morphology if the brain is refrigerated after death, and fixed by immersion within 3 hours. With latencies of fixation of 6 hours or more, autolytic changes supervene which modify the general histologic appearance and the morphology of individual cells. In general, the degree of tissue and cellular change is proportional to the latency between death and tissue fixation. Similar alterations in cellular morphology and general tissue appearance are found in Golgi-rapid impregnations of human brains obtained at autopsy. However, the degree of tissue autolysis in the human specimens bears a less predictable relationship to the latency of fixation after death. The duration of preterminal metabolic encephalopathy appears to be equally decisive as a determinant of tissue preservation.

Cellular events induced in the molecular layer of the piriform cortex by ablation of the olfactory bulb in the mouse

Cellular events associated with degeneration of the projection of the olfactory bulb to the molecular layer of the piriform cortex of the mouse have been studied with rapid-Golgi and Fink-Heimer impregnations and with the electron microscope. Four classes of axon terminals: s-1, s-d, f-1, and f-d, are differentiated on the basis of whether the synaptic vesicles are spherical or flattened and whether the axoplasm is lightly or darkly stained. The majority of s-1 terminals, the predominant class in sublamina Ia of the molecular layer, degenerate after bulb ablation. Degeneration of axon terminals is associated with dilation and, eventually, degeneration of segments of dendrites in Ia. Both s-1 and s-d terminals contribute to a partial reconstitution of the neuropil of Ia during the weeks after bulb ablation.

The cellular pathology of neuronal ceroid-lipofuscinosis. A golgi-electronmicroscopic study

A cerebral biopsy specimen from a 4-year-old girl with a moderately advanced stage of the late infantile form of neuronal ceroid-lipofuscinosis was observed in routine cell and fiber stains and in Golgi and electronmicroscopic preparations. There was no evidence of neuronal degeneration or loss. Golgi impregnations identified a fusiform enlargement of proximal axon segments of most pyramidal neurons and some polymorphic neurons but not of other cortical neuronal classes. Typical curvilinear inclusions were found in all cells and appeared to be impacted within the dilated proximal axon segments of pyramidal neurons. The numbers of type II synapses on the axon hillock and dilated proximal axon segments of pyramidal neurons were much reduced, whereas type I synapses remained abundant in the neuropil.

The cellular pathology of microgyria. A Golgi analysis

A case of extensive classical four layered cerebral microgyria was examined in whole brain serial section using routine cell and fiber stains, and in Golgi impregnations. Golgi preparations demonstrate that microgyric cortex contains the spectrum of neurons characteristically found in normal cortex, and that they are segregated by class into horizontal laminar comparable to layers I--VI in the normal. In microgyric cortex neurons of the mid-cortical layers, variably layers II--V, are replaced by a tangential band of fibrous astrocytes. These findings confirm impressions from general cell and fiber stains that classical four layered microgyria is the result of a destructive process striking predominantly in mid-cortical regions. It must occur after migration is complete but before the development of secondary and tertiary gyri, that is, between the fifth and seventh fetal months. The cellular pathology as seen in Golgi impregnations establishes that neurons surviving above the scar are normally differentiated, aligned, and oriented. By exception, many surviving neurons at the border of the scar have attenuated dendritic arbors which are oriented tangentially. Very few axons or dendrites actually traverse the scar.

Presentation of midgut malrotation in adults

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Experimental Evidence of the Local Production of ;Opsonins'

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