PubMed Health⌕ Search

Biomedical subjects

W C Halliday

Publications and source records attributed to W C Halliday.

35 records · Page 2Linked to original sources
PubMed1990

Intermediate filaments in the human pituitary gland: an immunohistochemical study.

Normal pituitaries, pituitaries showing CHC and selected adenomas were assessed for their possible content of intermediate filaments (IF), using immunohistochemical techniques. Normal pituitaries were stained for each of the five known IF (Cytokeratins (CK), glial fibrillary acidic protein (GFAP), desmin, vimentin, and neurofilaments (NF]. Desmin could not be demonstrated, and NF staining was limited to processes in the posterior gland. In serial sections, CK was demonstrated in some corticotrophs, somatotrophs, and lactotrophs. Vimentin was limited to processes in the posterior gland. Folliculo-stellate cells (FSC), demonstrated by staining for S100 protein, exhibited a small subpopulation staining for CK, and another subpopulation staining for GFAP. GFAP was also demonstrated in glial processes in the posterior gland. Cells showing Crooke's hyaline change stained intensely for CK. Null cell adenomas did not stain for CK. Corticotroph adenomas, somatotroph adenomas, with or without fibrous bodies, and lactotroph adenomas contain CK-immunoreactive cells. We conclude that CK is the major IF present in the anterior pituitary gland, within some normal corticotrophs, somatotrophs and lactotrophs, and also in adenomas derived from these cells.

Adenoma↗
PubMed1989

Inflammatory myopathy in F1 hybrid mice with acute graft-versus-host reactions.

Polymyositis and myasthenia gravis-like syndromes have been seen in patients with GVH disease following bone marrow transplantation. We therefore investigated the histopathology of muscle in mice with acute graft-versus-host disease in order to determine whether these conditions are caused by injury from the GVH reaction itself or are due to radiation and drugs used to prepare the host for transplantation. GVH reactions were induced by intravenously infusing 50 x 50(6) lymph node and spleen cells from A/J-strain donors into (C57BL/6 x A/J)F1-hybrid recipients. These mice developed an active inflammatory myopathy beginning 15 days after engraftment. The inflammatory infiltrates were focal in distribution, initially around perimysial blood vessels, and later around muscle fibers. The infiltrating cell population was composed of lymphocytes, plasmacytoid cells, and macrophages. Muscle cell necrosis was observed and was temporally related to elevations in serum creatine kinase. Similar histologic changes were present in the myocardium. Our findings support the notion that muscle involvement in patients with GVH disease is caused by the disease itself. Myositis accompanying experimental GVH disease in mice may hold promise as a model of autoimmune inflammatory myopathy.

Animals↗
PubMed1988

Leukoencephalopathy among native Indian infants in northern Quebec and Manitoba.

We report 14 cases of a severe familial leukoencephalopathy among native North American Indian infants in northern Quebec and Manitoba. Affected infants have hypotonia and mild motor delay, followed by seizures, hypotonia or spasticity, eye deviation, and abnormal posture during a febrile illness around 6 months of age. Death follows a rigid, vegetative state that manifests days to months after disease onset and is marked in some cases by prominent autonomic disturbances, blindness, and cessation of head growth. Symmetrical hemispheric white matter lucencies and diffuse hypomyelination of the cerebral hemispheres and brainstem are the radiological and pathological hallmarks. This disease differs from the known diseases of cerebral myelin. An autosomal recessive pattern of inheritance awaits statistical confirmation. The proposed cause is a delay in development or abnormal turnover of central nervous system myelin.

Brain↗
PubMed1988

The association of infantile osteopetrosis and neuronal storage disease in two brothers.

Neurological manifestations in infantile osteopetrosis are common and varied, and not always attributable to the skeletal pathology. An unusual association of osteopetrosis with neuronal storage of ceroid lipofuscin is reported in two infant brothers born of nonconsanguinous parents. The first child became symptomatic at age 5 days with weight loss and vomiting. He had poor head control, hypertonia, and persistent fisting, and died at age 2 months. In the second infant, the diagnosis of osteopetrosis was confirmed at age 2 days. His neurological symptoms included blindness, deafness, and recurrent seizures. The infant died at 7 months of age. In both cases, autopsy confirmed the diffuse bony sclerosis with hepatosplenomegaly and extramedullary hematopoiesis. Neuropathological examination revealed cerebral atrophy with ventricular dilation, neuronal loss, and astrogliosis. The most striking finding was widespread accumulation of neuronal ceroid lipofuscin associated with formation of axonal spheroids. The optic nerves were compressed at the optic foramina and showed loss of myelinated axons and gliosis. Rapid Golgi impregnations of neurons from the calcarine cortex in the second infant were analyzed quantitatively, showing a reduction in the total dendritic length and number of branches. The primary defect in osteopetrosis is thought to be a lysosomal dysfunction involving the monocyte cell line from which osteoclasts are derived. Thus, the association in two brothers of osteopetrosis with accumulation of neuronal ceroid lipofuscin may not be fortuitous. The neuronal storage disorder in this instance probably reflects lysosomal dysfunction.

Brain↗
PubMed1988

Human fetal adenohypophysis. Electron microscopic and ultrastructural immunocytochemical analysis.

The pituitary glands were removed from 63 human fetuses from 5 weeks of gestation to term and studied by electron microscopy and ultrastructural immunocytochemistry to document the development of cell differentiation and hormone production in the adenohypophysis. At 5 weeks of gestation, Rathke's cleft was lined by columnar epithelium with abundant cytoplasmic glycogen and occasional secretory granules. By 6 weeks of gestation, cells resembling corticotrophs were identified; in 8-week-old fetuses, type I microfilaments were found in those cells. Well-differentiated somatotrophs were seen in adenohypophyses of 8- to 9-week-old fetuses. Although secretory granules were numerous, the Golgi complex was inconspicuous in early fetal glands. After 10 weeks of gestation, there was a change with morphologic evidence of active hormone secretion; large Golgi regions and sparsely granulated cells were found. Some somatotrophs at this stage contained aggregates of type II microfilaments which resembled the fibrous bodies of sparsely granulated somatotroph adenomas. Densely granulated mammosomatotrophs containing growth hormone and prolactin were identified at 12 weeks of gestation. Cells with characteristics of the glycoprotein hormone cell line were seen in pituitaries at 12 weeks of gestation; thyrotrophs and gonadotrophs were identified after 15 weeks. Typical lactotrophs were not recognized before 23 weeks, but were numerous in pituitaries of fetuses older than 35 weeks. This study documents for the first time the existence of a bihormonal mammosomatotroph in the human fetal pituitary and confirms that somatotrophs and lactotrophs, the two acidophil cell types, are embryologically related.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1987

Wernicke's encephalopathy in patients on peritoneal dialysis or hemodialysis.

Although the occurrence of Wernicke's encephalopathy (WE) in patients on dialysis is frequently alluded to, review of the literature reveals only 3 described cases. We describe 5 patients on dialysis who developed WE in the absence of alcoholism or other predisposing factors. The clinical diagnoses included uremic encephalopathy (2 patients), dysequilibrium syndrome (1), dialysis dementia (1), and brainstem hemorrhage (1). At postmortem examination, classic findings of WE were evident. The rarity of WE in patients on dialysis may in part be explained by studies indicating a genetic defect in transketolase activity. Patients on dialysis are also potentially at risk for thiamine deficiency because of anorexia, vomiting, and intravenous alimentation. Other factors altering thiamine requirements, such as glucose load or infections, may also contribute. Preventable and potentially curable, WE should be suspected in all patients on dialysis who have an unexplained neurological picture.

Adult↗
PubMed1987

Thymic carcinoma with focal neuroblastoma differentiation.

A small, incidentally found, thymic carcinoma (malignant thymoma) showed an extraordinary mixed-cell composition. The tumor was predominantly made up of poorly differentiated cells with light-microscopic, ultrastructural, and immunohistochemical features of thymic epithelium. However, small distinct groups of cells displaying features of neuroblastoma were scattered throughout the tumor. This unique case further illustrates the multiple capabilities of differentiation of thymic tumors.

Humans↗
PubMed1987

Choroid plexus tumors in children: immunohistochemical and scanning-electron-microscopic features.

The 30 choroid plexus tumors recorded in a large pediatric tumor registry were reviewed. The 22 choroid plexus papillomas and 8 choroid plexus carcinomas represented 2.1% of all brain tumors in the registry. The patients (19 boys, 11 girls) were aged 3 months to 12 years (mean: 2 years 9 months). All tumors and four samples of normal choroid plexus were examined with conventional histology, 9 tumors were examined with electron microscopy and 24 using immunohistochemical techniques with antisera against glial fibrillary acidic protein, S-100 protein, epidermal cytokeratin, internal organ cytokeratin and carcinoembryonic antigen. Seven of the tumors (1 carcinoma and 6 papillomas) had some positive cells with antiserum against glial fibrillary acidic protein. Twenty-seven of the tumors (90%) and all normal choroid plexus samples were positive with antiserum to S-100 protein. Some tumor cells from both types of tumor and the normal choroid plexus reacted positively with internal organ cytokeratin antiserum, but all tissue samples were nonreactive with epidermal cytokeratin antiserum. Ultrastructurally, both papillomas and carcinomas displayed cytoplasmic intermediate filaments. Transmission and/or scanning electron microscopy revealed cilia in all choroid plexus papillomas. Frequently, the cilia had an abnormal arrangement, varying from 5 + 0 to 8 + 1. This study demonstrates that tumor cells of choroid plexus origin are characterized by the presence of S-100 protein and internal organ cytokeratin antiserum. Cilia, either normal or abnormal, are consistently identified in papillomas but rarely and with difficulty in carcinomas. Carcinoembryonic antigen is seen in choroid plexus carcinomas but not papillomas.

Adolescent↗
PubMed1986

Cerebral complications following balloon angioplasty of coarctation of the aorta.

A 10-month-old male child underwent balloon angioplasty for a recurrent coarctation of the aorta. Postprocedural hemorrhagic cerebral infarction led to the child's death. At necropsy, hypoplasia of the left posterior communicating artery of the circle of Willis was found. The implications of such variations in cerebral blood flow circulation on the angioplasty technique are presented and discussed.

Angioplasty, Balloon↗
PubMed1986

Glial fibrillary acidic protein (GFAP) in oligodendrogliomas: a reflection of transient GFAP expression by immature oligodendroglia.

Fourteen pure oligodendrogliomas were studied by light- and electronmicroscopy and immunohistochemistry to examine glial fibrillary acidic protein (GFAP) positivity in the tumors. To compare the immunohistochemical staining patterns of neoplastic oligodendroglia and immature oligodendroglia, myelination glia in the white matter of eight normal brains from children under 6 months of age were studied. The tumors possessed light microscopic and ultrastructural features characteristic of oligodendrogliomas. Microtubules were found in the cytoplasm of nine tumors on electronmicroscopy. In one, intermediate filaments and microtubules were observed in occasional tumor cells with polygonal crystalline structures in the cytoplasm. Using the peroxidase-antiperoxidase technique, all specimens were stained for GFAP, vimentin, S-100 and neuron-specific enolase (NSE). In nine tumors, variable numbers of cells with an oligodendroglial morphology reacted positively for GFAP. All tumors were positive for S-100 and negative for vimentin and NSE. The myelination glia in the eight normal brains stained positively for GFAP but not for vimentin. Vimentin is expressed by developing, reactive and neoplastic astrocytes. Thus, GFAP positivity combined with vimentin negativity in both neoplastic and immature oligodendroglia suggests that GFAP positivity in oligodendrogliomas may reflect the transient expression of this intermediate filament by immature oligodendroglia.

Brain↗
PubMed1985

Intermediate filaments in meningiomas.

The presence of intermediate filaments (IF) (diameter 10 nm) is a characteristic electron microscopic finding in the cytoplasm of meningioma cells. To identify these IF, immunohistochemical staining for cytokeratins and vimentin and two-dimensional (2-D) gel electrophoresis followed by immunoblot analysis were applied to a group of 16 meningiomas. Thirteen meningiomas were obtained directly from surgery and three came from an autopsy in which they were found in close proximity as discrete tumor masses. Except for the angioblastic type, all major histological variants were represented (nine transitional, four syncytial, and three fibroblastic). None of the meningiomas stained for epithelial or internal organ cytokeratins. With monoclonal antibodies, each of the meningiomas stained positively for vimentin. Two-D gels revealed vimentin and vimentin breakdown products as the only IF present; these findings were verified by immunoblots. The study concludes that vimentin is the IF present in fibroblastic, syncytial, and transitional meningiomas.

Cytoskeleton↗
PubMed1984

Primary rhabdomyosarcoma of the cerebellum--a light, electron microscopic, and immunohistochemical study.

A primary cerebellar rhabdomyosarcoma (RMS) in a six and a half year old boy is reported. Microscopy of the surgical material revealed lobules of closely packed cells with a high mitotic rate, pleomorphic hyperchromatic nuclei and scant cytoplasm. At their periphery, the lobules merged with rounded cells with similar nuclei but more abundant cytoplasm. These areas were surrounded by interlacing fascicles of strap cells, which were occasionally multinucleated and showed cross striations. Electron microscopy (EM) revealed the primitive nature of the closely packed cells; however, occasional intermediate size filaments were present within their cytoplasm and focal basement membrane accumulation was observed. Cells with more abundant cytoplasm had large accumulations of thick and thin filaments while strap cells showed well-developed cross striations. Immunohistochemical studies (peroxidase-antiperoxidase technique) showed vimentin in the primitive cells and desmin, myoglobin and adenosine triphosphatase as the tumor cells appeared more differentiated. Immunoreaction with antibodies against glial fibrillary acidic protein, S-100 protein and neurofilament protein were negative. Electron microscopic and immunohistochemical studies in this case demonstrated that this was an exclusively mesenchymal tumor with rhabdomyoblastic differentiation and that the pattern of differentiation follows that seen in normal myogenesis.

Cerebellar Neoplasms↗
PubMed1984

Thalamic tumors in children. Long-term follow-up and treatment guidelines.

The authors review the cases of 60 children (aged 5 months to 18 years) with thalamic tumors who were seen at The Hospital for Sick Children between 1951 and 1983. The diagnosis of thalamic tumor was based on neuroradiological studies; 33 children were first seen in the pre-computerized tomography (CT) era and 27 since the advent of CT scanning. Histological diagnosis was obtained in 37 patients at the time of operation. A further four tumors were verified histologically at autopsy. Thirty-six patients required cerebrospinal fluid shunt placement. Sixteen patients had no surgery on their tumor, three underwent needle biopsy, 20 underwent open biopsy, and 21 had partial resection. Forty-four patients were irradiated. All 20 patients with malignant tumors died, with a mean survival time of 1.1 years. Of 19 patients with benign tumors, 11 died, with a mean survival time of 5.3 years, and eight are still alive after a mean period of 7.2 years since diagnosis. Based on this series, the authors recommend open biopsy of thalamic tumors (and resection if deemed safe), followed by radiation in selected cases.

Adolescent↗
PubMedDate not supplied

Human immunodeficiency virus-associated progressive multifocal leukoencephalopathy: apparent response to 3'-azido-3'-deoxythymidine.

We present the case of a 26-year-old human immunodeficiency virus-seropositive man who developed progressive multifocal leukoencephalopathy as the initial manifestation of AIDS. He appears to have responded dramatically to therapy with 3'-azido-3'-deoxythymidine (AZT). His neurologic status deteriorated shortly after an AZT dose reduction. He has stabilized since resuming his previous AZT dose. Although it remains unclear whether AZT is useful in the treatment of JC virus infection, we think that all AIDS patients with progressive multifocal leukoencephalopathy should be offered treatment with AZT, especially in light of recent reports describing a possible potentiation of human immunodeficiency virus infection of the central nervous system in this setting.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Hallervorden-Spatz disease: MR and pathologic findings.

PURPOSE: To compare the MR findings of eight cases with clinical diagnosis of Hallervorden-Spatz disease (HSD) with the pathologic findings of two other cases of HSD. MATERIALS AND METHODS: The eight imaged cases were studied with 0.5-T (seven cases) and/or 1.5-T (five cases) units. Six patients also had CT scans. The two other cases with proven HSD had detailed histologic evaluation. RESULTS: The 1.5-T findings showed abnormalities confined to the pallidum, which presented a diffuse low signal intensity in T2-weighted images, and an anteromedial area of high signal intensity (eye-of-the-tiger sign). In 0.5-T studies, low signal intensity was less evident and poorly detectable in spin echo, but gradient-echo images could enhance its demonstration; the area of high signal intensity was always well demonstrated. In three cases (three with 1.5 T, one with 0.5 T) a central spot of low signal intensity was seen in this area. The pathologic cases, in addition to neuroaxonal swellings and iron deposits, exhibited areas of "loose" tissue with vacuolization and lesser amounts of iron in the anteromedial part of the pallidum, in a location corresponding to the area of high signal intensity of the imaged cases. CONCLUSION: Comparison of MR findings with the pathologic studies demonstrates that the low signal intensity in T2-weighted images at 1.5 T corresponds to iron deposits in a dense tissue, and that the high signal intensity of the eye-of-the-tiger sign corresponds to an area of loose tissue with vacuolization. No correlation was found in the two pathologic cases for the central spot of low signal intensity.

Adolescent↗
PubMedDate not supplied

Mobile lipid accumulation in necrotic tissue of high grade astrocytomas.

Multiple samples from 42 astrocytomas were investigated ex vivo by 1H MR spectroscopy followed by histological assessment. MR visible lipids were detected in 27 of 32 grade 4 astrocytomas. These lipids were heterogeneously distributed within the tumours. Their amount correlated positively with the amount of histologically detected necrosis. Mobile lipids were also observed in grade 4 astrocytoma samples without necrosis, as well as in one of three grade 3, two of three grade 2 and two of four grade 1 astrocytomas. The clinical significance of MR visible lipids, their cellular location, and their possible biological bases are discussed.

Astrocytoma↗