Search PubMed⌕ Search

Biomedical subjects

J A Royds

Publications and source records attributed to J A Royds.

At least 55 records · Page 3Linked to original sources
PubMed1988

Stromal cells in cerebellar haemangioblastomas: an immunocytochemical study.

The nature of the stromal cells in formalin-fixed paraffin-embedded material from 23 cerebellar haemangioblastomas was investigated using antisera to intermediate filaments (glial fibrillary acidic protein, vimentin and desmin), histiocytic markers (alpha 1-antitrypsin, alpha 1-antichymotrypsin and lysozyme), glycolytic enzymes (alpha and gamma enolase and aldolase C4) and the endothelial markers, factor VIII related antigen and Ulex europaeus I lectin. Most stromal cells stained positively for vimentin and the glycolytic enzymes. Occasional process-bearing cells within the stroma stained strongly for glial fibrillary acidic protein, alpha 1-antitrypsin and alpha 1-antichymotrypsin. No stromal cell staining for desmin, lysozyme or the endothelial markers was observed, although the latter stained the vascular endothelium within all neoplasms. The findings do not support previous suggestions of an endothelial or histiocytic origin for the stromal cells. They appear to be a heterogeneous population including entrapped reactive astrocytes and locally-derived non-angiogenic cells of neuroectodermal (pial) origin.

Adolescent↗
PubMed1987

Serum aldolase isoenzymes in benign and malignant liver disease.

Using a radio-immunoassay, aldolase A and B isoenzyme concentrations have been measured in the sera of patients in order to assess their specificity and sensitivity in a variety of hepatic disorders. Serum aldolase A has been confirmed to be elevated in some patients with malignant infiltration of the liver, but its sensitivity is not sufficient to be of clinical value. Aldolase B is a sensitive marker of liver cell damage which correlates closely with conventional biochemical markers of inflammation. It appears to distinguish successfully between hepatic and cardiac damage.

Fructose-Bisphosphate Aldolase↗
PubMed1987

Immunolocalisation of cytokeratins in the normal and neoplastic human pituitary gland.

Cytokeratins were studied by immunocytochemical techniques at light and electron microscopy on 12 normal pituitary glands, 30 pituitary adenomas and three craniopharyngiomas. The results are presented in relation to clinical and biochemical features and new information on the subcellular localisation of cytokeratins in pituitary cells is discussed.

Adenoma↗
PubMed1987

Childhood leukemia: cerebrospinal fluid enolase isoenzymes in central nervous system infiltration.

Enolase isoenzymes were measured in the cerebrospinal fluid of seven consecutive children with lymphoblastic leukemia who developed meningeal (CNS) leukemia. Assays were performed at the time CNS disease was discovered and during the subsequent 4 weeks. Three of the seven were also examined 1-3 months before CNS relapse was confirmed. Fourteen children on similar systemic therapy without CNS infiltration served as controls. Prior to and at the onset of CNS disease alpha enolase was elevated in all patients studied. The gamma form was raised in only one beforehand and only three at the time of relapse. The alpha isoenzyme was related to the blast cell count and fell during therapy in all but one child, whereas the gamma was not and showed no significant change. The three patients with raised gamma enolase were the only children with other than common lymphoblastic leukemia. There was no clear indication whether either enzyme concentration had any importance in terms of disease outcome, although one child developed a further CNS relapse 10 months later. He was the only patient whose alpha enolase rose following intrathecal methotrexate. Neuronal disruption due to common lymphoblastic leukemia in the CNS appears to be minimal. Other types of leukemia may give rise to more neuronal damage. The alpha isoenzyme, from glial tissue and malignant cells, may be elevated even in the absence of detectable blasts in the cerebrospinal fluid and may be a sensitive marker of CNS infiltration in such circumstances.

Brain Neoplasms↗
PubMed1986

An immunohistochemical study of glial and neuronal markers in primary neoplasms of the central nervous system.

Paraffin-embedded tissues from 56 primary neoplasms of the central nervous system and seven cases of non-neoplastic reactive astrocytosis were examined by immunoperoxidase techniques on serial sections using monoclonal antibodies to glial fibrillary acidic protein (GFAP) and the 68 kDa neurofilament subunit and monospecific polyclonal antibodies to alpha- and gamma-enolase. gamma-Enolase was present in all neoplasms of neuronal origin, but was also present in anaplastic gliomas (particularly in giant cells), in some well-differentiated astrocytomas and reactive astrocytes. The cells containing gamma-enolase in these cases appeared morphologically identical to those containing alpha-enolase and GFAP in adjacent serial sections. No relationship was found between gamma-enolase immunoreactivity and cellular anaplasia in the gliomas studied. Subependymal neoplasms from patients with tuberose sclerosis exhibited evidence of both astrocytic and neuronal differentiation, sometimes in morphologically distinct cell populations, consistent with their suggested origin from a primitive cell line.

Astrocytes↗
PubMed1985

Paraganglioma of the cauda equina: a histological, ultrastructural and immunocytochemical study of two cases with a review of the literature.

The clinical and pathological features of two paragangliomas arising in the cauda equina are described and compared with 14 previous reports. The light microscopic features were similar to those of paragangliomas from other sites, with a 'Zellballen' pattern of cells containing argyrophil granules. Electron microscopy showed densely staining membrane-bound granules, cilia and fibrous bodies in the cytoplasm. The last two features only occur in paragangliomas from this site. gamma-Enolase was demonstrated by the peroxidase-antiperoxidase technique for the first time in these neoplasms. This technique was also used to demonstrate cytokeratins, which appear to be associated with the presence of fibrous bodies. The pathological findings suggest that paragangliomas in this site arise from pre-existing paraganglia, possibly of the visceral autonomic group. The prognosis in cases treated by complete excision appears to be good.

Adult↗
PubMed1985

Comparison of beta enolase and myoglobin as histological markers of rhabdomyosarcoma.

A comparative study of beta enolase and myoglobin as markers of muscle differentiation in rhabdomyosarcoma was carried out, using an immunoperoxidase peroxidase antiperoxidase technique. Material from 26 cases of childhood rhabdomyosarcoma was studied and subdivided into embryonal and alveolar types. Positive cytoplasmic staining for beta enolase was seen in 85% of tumours studied (91% alveolar, 79% embryonal), whereas positive staining for myoglobin was detected in only 69% of tumours (82% alveolar, 64% embryonal). beta Enolase and myoglobin are useful in the histological diagnosis of rhabdomyosarcoma, and of the two, beta enolase seems to be the more sensitive.

Cell Differentiation↗
PubMed1984

Cerebrospinal fluid enolase isoenzymes and neurotoxicity in early treatment of lymphoblastic leukaemia.

Serial measurements of enolase in the cerebrospinal fluid were made in 19 children with lymphoblastic leukaemia undergoing their first 6 weeks of antineoplastic treatment. The neurone-specific gamma enolase value rose appreciably in nearly all patients during the first two weeks of treatment, which comprised chemotherapy only, but the mean values for this isoenzyme failed to show any further rise during the subsequent cranial irradiation. In contrast the alpha enolase value, which is derived predominantly from glial tissue, rose progressively to attain its highest value during radiotherapy. A consideration of the likely rate of clearance of gamma enolase from the cerebrospinal fluid and the time sequence of administration of the several chemotherapeutic agents in UKALL VIII suggests that asparaginase may be the main causative agent in the rise of this marker of neuronal damage.

Asparaginase↗
PubMed1984

An investigation of beta enolase as a histological marker of rhabdomyosarcoma.

Sections from 21 tumours diagnosed as primary or metastatic rhabdomyosarcoma were stained for alpha and beta enolase. The cases were subdivided into embryonal and alveolar subtypes (38% and 62%, respectively). Positive cytoplasmic staining for alpha enolase was seen in all but one case, and cytoplasmic staining for beta enolase was seen in some cells in 18 of the 21 cases (86% of the total, 88% of the alveolar subgroup, and 85% of the embryonal subgroup). No cells stained positively for beta enolase in the control series of neuroblastomas, fibrosarcomas, Wilms' sarcomas, and an osteosarcoma. The results show that beta enolase is a sensitive marker of muscular differentiation in rhabdomyosarcoma.

Clinical Enzyme Tests↗
PubMed1984

Cerebrospinal fluid enolase in stroke.

This study relates the level of alpha and gamma enolase in cerebrospinal fluid sampled within 4 days of a stroke to the volume of the cerebral infarct measured on the CT image and to the clinical outcome of the patient. Twenty-eight patients were studied, two with transient ischaemic attacks and 26 with completed stroke due to infarction. The cerebrospinal fluid enolase was raised in the two patients with transient ischaemic attacks and 23 with completed stroke. There was a positive correlation between the volume of the infarct and the level of cerebrospinal fluid alpha and gamma enolase. A high cerebrospinal fluid enolase was always associated with a poor prognosis.

Adult↗
PubMed1983

Enolase isoenzymes in uveal melanomas--a possible parameter of malignancy.

Seven uveal melanomas were stained for gamma enolase by an immunoperoxidase PAP (peroxidase-antiperoxidase) technique, and biochemical assays were carried out on tissue homogenates. A correlation between the biochemical assay and the immunoperoxidase staining was demonstrated. Two tumours with the highest biochemical assays showed positive staining for the enzyme, and 2 tumours with the lowest levels showed no appreciable staining. The highest level of enolase was present in a tumour which both clinically and histologically appeared to be benign, and the lowest level occurred in a mixed cell tumour which was large in size; the low level presumably related to its relatively fast rate of growth. Estimation of gamma enolase activity in ocular melanomas may provide an accurate quantitative method for assessing the malignant potential of these tumours.

Adult↗
PubMed1982

Enolase isoenzyme distribution in the human brain and its tumours.

Using the immunoperoxidase PAP method we have studied the cellular distribution of alpha, beta and gamma enolase subtypes in normal human adult brain and in human brain neoplasms. Gamma enolase is found only in viable neurones throughout the brain. Alpha enolase is demonstrable in astrocytes, ependymal cells, capillary endothelial cells. Schwann cells and arachnoidal endothelial cells but oligodendrocytes appear to have low levels of this isoenzyme. Beta enolase is not demonstrable in normal brain tissues. Of the primary cerebral neoplasm studied only medulloblastomas and neuroblastomas did not contain demonstrable enolase. Astrocytomas, ependymomas, oligodendrocytomas, meningiomas and acoustic neuromas all contained varying quantities of alpha enolase. No cerebral tumours contained beta or gamma enolase. Tumour and adjacent brain tissue with histological evidence of ischaemia and necrosis showed loss of cellular enolase.

Adolescent↗
PubMed1981

Levels of enolase and other enzymes in the cerebrospinal fluid as indices of pathological change.

The activities of enolase, aldolase, pyruvate kinase, lactate dehydrogenase and creatine phosphokinase were measured in cerebrospinal fluid of 121 patients presenting with a range of disorders of the central nervous system. The results from 41 patients undergoing myelography were used as controls. An assessment was made of the relative merits of these five enzymes as markers of brain damage with special reference to brain tumours. Enolase was the most sensitive marker of pathological change and was the only enzyme raised in the CSF of patients with low grade astrocytomas.

Adenoma↗
PubMedDate not supplied

Carcinoid tumour arising in a recurrent intradural spinal teratoma.

We report the case of a recurrent intradural spinal teratoma in a 44-year-old woman. Histological examination showed the lesion to be composed entirely of mature elements including an argyrophil carcinoid tumour. Electron microscopy showed the neoplastic cells to possess the ultrastructural features of a foregut type APUDoma. Gamma enolase, a marker of APUD cells, was demonstrated in the neoplasm by the peroxidase-antiperoxidase technique. This method was also used to demonstrate the presence of cytokeratins in the neoplastic cells and the squamous and columnar epithelia within the teratoma. These results are consistent with the suggestion that APUD cells of foregut type may be of endodermal rather than neuroectodermal origin.

Adult↗