Search results for "Ultrastructure"
showing 10 items of 224 documents
Neuropathologic and morphometric studies in hereditary motor and sensory neuropathy type II with neurofilament accumulation.
1986
Histological, electron microscopic and morphometric data on sural nerve, muscle, and skin biopsies of three patients affected by autosomal dominant hereditary motor and sensory neuropathy type II with neurofilament accumulation, whose neurological, cardiological and electrophysiological data have been provided in a previous paper disclosed focally enlarged myelinated axons, due to aggregation of neurofilaments in sural nerves of all 3 biopsied patients, as well as densely packed clusters of filaments in occasional non-myelinated axons without axonal enlargement, in several fibroblasts and endothelial cells in muscle and particularly in skin. This accumulation of filaments was less pronounce…
Resistance of subventricular neural stem cells to chronic hypoxemia despite structural disorganization of the germinal center and impairment of neuro…
2015
Xavier d'Anglemont de Tassigny,1,* M Salomé Sirerol-Piquer,2,3,* Ulises Gómez-Pinedo,4 Ricardo Pardal,1 Sonia Bonilla,1 Vivian Capilla-Gonzalez,2 Ivette López-López,1 Francisco Javier De la Torre-Laviana,1 José Manuel García-Verdugo,2,3 José López-Barneo1,3 1Medical Physiology and Biophysics Department, Institute of Biomedicine of Seville (IBiS), Virgen del Rocío University Hospital/CSIC/University of Seville, Seville, Spain; 2Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, Valencia, Spain; 3Network Center of Biomedical Research on Neurodegenerati…
Granular cell ameloblastoma of jaw: report of a case with an emphasis on its characterization
2013
Ameloblastoma is a neoplasm of odontogenic epithelium, especially of enamel organ-type tissue that has not undergone differentiation to the point of hard tissue formation. It accounts for approximately 10% of all tumors originating from gnathic bones. It exhibits diverse microscopic patterns which occurs either singly or in combination with other patterns. Granular cell ameloblastoma is a rare condition, accounting for 3.5% of all ameloblastoma cases that shows marked transformation in the cytoplasm of tumor cells, which are usually stellate reticulum like cells. The transformed cells possess very coarse, granular, eosinophilic cytoplasm. The “granular change” is thought to be due to a dysf…
Comparative study of T84 and T84SF human colon carcinoma cells: in vitro and in vivo ultrastructural and functional characterization of cell culture …
2005
To better understand the relationship between tumor heterogeneity, differentiation, and metastasis, suitable experimental models permitting in vitro and in vivo studies are necessary. A new variant cell line (T84SF) exhibiting an altered phenotype was recently selected from a colon cancer cell line (T84) by repetitive plating on TNF-alpha treated human endothelial cells and subsequent selection for adherent cells. The matched pair of cell lines provides a useful system to investigate the extravasation step of the metastatic cascade. Since analysis of morphological differences can be instructive to the understanding of metastatic potential of tumor cells, we compared the ultrastructural and …
An ultrastructural study on retinal neural and pigment epithelial cells in ovine neuronal ceroid-lipofuscinosis.
1990
Ovine neuronal ceroid-lipofuscinosis represents another well studied model for human neuronal ceroid-lipofuscinosis (NCL). Accumulation of abnormal lipopigments in various retinal neurons, and loss of photoreceptors are similar to the lesions in human juvenile NCL and indicate that the sheep is a suitable model in which to study the pathogenesis of both NCL lipopigment formation and retinopathia pigmentosa. However, this latter process is not as advanced in NCL-diseased sheep as in human patients but far more obvious than in canine NCL in which retinopathy cannot be unequivocally documented. Ovine NCL shares with canine NCL peculiar lamellar inclusions in retinal pigment epithelial cells wh…
AN ULTRASTRUCTURAL STUDY OF THE RETINA IN HUMAN LATE INFANTILE NEUROAXONAL DYSTROPHY
1993
A case involving a girl who died at 11 years of age and who had developed normally until the age of 18 months, at which time further psychomotor maturation stopped and then regressed, is reported. The patient appeared hypotonic and showed loss of deep tendon reflexes, as well as bulbar signs and increasing immobility. Visual impairment resulted in blindness at the age of 7 years. Her disease was diagnosed as late infantile neuroaxonal dystrophy (LINAD) after examination of sural nerve biopsy samples and after autopsy. Under electron microscopy, retinal axons were filled with tubulocisternal profiles and occasional large lamellar clefts close to or distant from synaptic complexes. These lesi…
Fibroblast and Myofibroblast Participation in Malignant Fibrous Histiocytoma (MFH) of Bone
1989
Eight malignant fibrous histiocytomas (MFH) of bone were studied with immunohistochemistry and electron microscopy. Ultrastructurally, fibroblasts and myofibroblasts were the main tumor cells in four cases and abundant in two other cases; these cells showed immunohistochemical positivity to alpha 1-antitrypsin, vimentin and anti-muscle antigen (HHF 35). Moreover, histiocytic-like tumor cells were electron-microscopically detected in four cases, being the main tumor cell type in two of the cases; immunohistochemically these cells expressed positivity to alpha-1-antichymotrypsin (A1ACT), alpha-1-antitrypsin (A1AT) and vimentin. Present results confirm the cellular heterogeneity of MFH of bone…
Gastrin-cholecystokinin-like immunoreactivity in the central nervous system of the milkweed bug, Spilostethus pandurus. Ultrastructural aspects of th…
1995
Summary All the ganglia belonging to the central nervous system of adults of the milkweed bug Spilostethus pandurus (Hemiptera) were screened immunohistochemically for vertebrate gastrin-cholecystokinin (CCK-8(s))-like peptides. Several large reactive perikarya are present in the median part of the protocerebrum, their processes extending to the dorsal ‘aorta’. These cell bodies are also paraldehyde fuchsin-positive, ie they are A-type cells. In the lateral part of the protocerebrum, in the deutocerebrum and tritocerebrum, and in the suboesophageal, prothoracic and abdominal ganglia, a few immunoreactive cell bodies send axonal processes into their respective neuropiles. The A-type cells re…
Ultrastructural study of primary canine and human pigmentary retinopathy
1985
An electron microscopic study was performed on eyes of Labrador dogs afflicted with progressive retinal atrophy (PRA). There was complete loss of photoreceptors, atrophy of the remaining retina and gliosis in the peripheral part while the central retina showed incomplete loss of photoreceptors and an almost total disappearance of photoreceptor outer segments. Melanin-bearing cells, largely containing melanolysosomes, were found deep inside the retina. This electron microscopic study also incorporated the retina of a middle-aged woman affected by retinopathia pigmentosa (RP). The fine structure of the diseased retina showed a similar pattern of lesions, more pronounced in the periphery of th…
Nemaline myopathy with intranuclear rods--intranuclear rod myopathy.
1997
Among the different nosological forms of nemaline/rod myopathy, one morphological variant is marked by intranuclear rods in addition to sarcoplasmic rods. Such patients fall into two categories: firstly, adults and secondly, young infants suffering from the severe form. Intranuclear rods indicate unfavourable prognosis. Recently, intranuclear rods without sarcoplasmic rods have also been encountered. Intranuclear rods, largely solitary, are often found large in size with the ultrastructural lattice pattern of sarcoplasmic rods and Z-disks. They contain alpha-actinin and actin. The origin of intranuclear rods is still enigmatic. Their presence within nuclei without sarcoplasmic rods points t…