Neoplastic changes involving follicles: morphological, immunophenotypic and genetic diversity of lymphoproliferations derived from germinal center and mantle zone.
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Biomedical subjects
Publications and source records attributed to J Hugh.
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A system consisting of an interlacunar network and thick fibrils was demonstrated in the matrix of human fetal and neonatal hyaline cartilage, using an osmium-ferrocyanide mixture as a second fixative. The network appeared as irregular strands consisting of hyaluronidase-sensitive, amorphous and fine fibrillar material. The thick fibrils measured 75-125 microns in diameter, each appearing to consist of several collagen fibrils twisted into a cable and cemented by dense amorphous material. Strands of the network were seen to cross and focally distort the thick fibrils, suggesting that the strands exert some tensile forces on the thick fibrils. During the first year of life the network rapidly became undemonstrable, but the thick fibrils persisted into adulthood. This system of interlacunar network and thick fibrils appears to form an integral functional unit which may play an organizational role in the formation of cartilagenous matrix during development. Furthermore, it may contribute to the mechanical strength of the collagen framework in hyaline cartilage.
Fibrocartilaginous talocalcaneal coalitions are very difficult to identify on plain radiography in symptomatic children and adolescents before gross ossification occurs. Computed tomography (CT) has been successful in identifying osseous and some fibro-osseous coalitions. In this series, magnification imaging of the tarsus on bone scintigraphy in the medial-lateral projection correctly identified talocalcaneal coalitions, seven of the nine bars were fibrous or fibro-osseous. Three of the fibrous lesions were equivocal or normal on conventional radiography and CT. Physiologic accumulations of activity in the growing hind foot are also presented from a control pediatric population. Magnification scintigraphy of the hind foot is offered as an adjunct to plain radiography and CT in the diagnosis of elusive nonosseous subtalar bars.
Extraspinal ependymomas have been described in the subcutaneous sacrococcygeal and presacral areas. Since 1984, eight pelvic ependymomas have been reported that have originated in the ovary, broad ligament, mesovarium, and omentum. This report documents an additional case arising from the right uterosacral ligament in a 48-year-old woman. The diagnosis of ependymoma was supported by a histologic pattern of true rosettes and pseudo-rosettes, glial fibrillary acidic protein (GFAP) positivity, and electron microscopic findings of cilia, blepharoplasts, and intermediate filaments. The tumor was positive for cytokeratin and vimentin. Ultrastructurally, neurosecretory granules were present within the cytoplasm. These features have not been described previously in pelvic ependymomas. These tumors, although easily confused with serous papillary carcinoma, should be distinguished from serous papillary carcinoma because of their apparently better prognosis and tendency for late recurrence.
Three clinical cases of profound hypoglycemia are described with survival periods ranging from 2 1/2 months to 6 years. Although prolonged clinical coma was present in all cases, only subtle evidence of neuronal loss was found. The value of immunohistochemical examination of the grey and white matter of the telencephalon in detecting evidence of neuronal loss in such cases is demonstrated. Infarcts were uniformly absent, as would be expected from the lack of cerebral acidosis in hypoglycemia. In addition to the usual absence of infarction, the pathologic findings in hypoglycemia distinguish themselves from hypoxic/ischemic encephalopathy in that the cerebellum is regularly spared, and that there is sometimes a characteristic involvement of the dentate gyrus, a structure relatively resistant to hypoxic/ischemic damage.