Manuel E. Velasco

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In this study, we found that neuropil threads of Alzheimer disease, rather than being continuous filaments along cell processes, show multiple interruptions. They are segmental in nature and therefore appear as striations rather than continuous filaments along the length of the neurite. Neuritic striation is not an artifact of section thickness since the(More)
The presence of glial fibrillary acidic protein (GFAP) was studied in human pituitary glands with the peroxidase-antiperoxidase (PAP) method. Positive reaction was observed in cells and processes of the neurohypophysis, in occasional cells lining the Rathke's cysts of the pars intermedia, and in scattered star-shaped cells and small follicles of the pars(More)
Human ependymal cells show positive immunostaining for glial fibrillary acidic protein (GFAP) at one stage of the fetal development. The reaction seems to coincide with maturation of the epithelial layer and development of cilia. Two types of reactive cells are present: epithelial and tanycytes. The GFAP-positive reaction in both these cells is transient,(More)
The presence and distribution of glial fibrillary acidic protein in fixed, paraffin embedded tissue were studied in 85 human intracranial neoplasms, using the peroxidase-anti-peroxidase method. In some cases, indirect immunofluorescence of frozen sections was used as well. In normal tissue, only the cell processes and perikarya of fibrous astrocytes were(More)
Neuroepithelial neoplasms of childhood were examined immunohistochemically using antibodies against a neurofilament polypeptide and glial fibrillary acidic protein. Ninety-one cases, including 11 controls, were examined. Positively reacting cells, indicating neuronal and glial differentiation, were found in 59 of the 80 tumors. The study supports a(More)
In cerebral amyloid angiopathy, the amyloid-beta (A beta) deposits lie primarily in the tunica media suggesting that smooth muscle cells play an important role in A beta deposition. To define this role, we conducted an immunocytochemical study of brain tissue from cases of Alzheimer disease with extensive cerebral amyloid angiopathy and cerebral hemorrhage.(More)
We describe two patients and a previously reported patient who acquired unique pendular vergence oscillations of the eyes and concurrent contractions of the masticatory muscles, i.e., oculomasticatory myorhythmia (OMM). The smooth disjunctive eye movements cycled with a frequency of 0.8 to 1.2 Hz. An analysis of peak velocities (15 to 200 degrees/sec) with(More)
The histopathological and autonomic effects of percutaneous trigeminal ganglion compression for trigeminal neuralgia were studied in New Zealand White rabbits. Drops in mean arterial blood pressure of 38% and in heart rate of 30% were observed during compression (p less than 0.0001). Corneal reflex, pinprick sensation, and mastication strength were intact(More)
A child with shunted hydranencephaly and presumed ventriculitis was found to have a primary congenital rhabdoid tumor (RT) of the brain. The child died and a complete autopsy was carried out. The cerebral hemispheres were replaced by a single thin-walled cavity studded with tumor nodules and filled with thick, viscous fluid. The posterior fossa and visceral(More)
A technique for rapid diagnosis of astroglial and ependymal glial neoplasms is presented. Frozen sections are processed for immunofluorescence using anti-serum raised against the glial fibrillary acidic (GFA) protein. The entire procedure requires 10--15 minutes. The technique is useful for the rapid identification of neoplasms of astroglial and ependymal(More)