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A G Pearse

Publications and source records attributed to A G Pearse.

At least 19 recordsLinked to original sources
PubMed1986

Pieter van Duijn.

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Histocytochemistry↗
PubMed1984

Neuron-specific enolase in the pituitary gland.

Neuron-specific enolase (NSE) is present in many types of peptide-secreting neuroendocrine cells and in tumours derived from them, but little work has been done on the pituitary gland. Serial sections of normal rat (n = 9) and human (n = 7) pituitary gland, spontaneous rat pituitary tumours (n = 14) and human pituitary tumours, both hormonally active (n = 7) and inactive (n = 10), were immunostained for NSE and the 6 major anterior pituitary hormones. The neural lobe stained strongly and the intermediate lobe variably for NSE. In the anterior lobe, NSE immunoreactivity was present with variable intensity in the majority of hormone-producing cells of all six types. Cells with strong hormone immunoreactivity were usually only moderately stained for NSE. All the human and rat pituitary adenomas examined were positively stained for NSE, though to varying degrees. The pituitary gland is thus no exception to the rule that NSE is found in peptide-secreting neuroendocrine cells and their tumours.

Acromegaly↗
PubMed1983

Immunostaining of neuron-specific enolase as a diagnostic tool for Merkel cell tumors.

Conventional histologic examination of Merkel cell tumors may result in misdiagnosis because of the close similarities these tumors bear to either malignant lymphomas or certain undifferentiated carcinomas. The authors have previously reported that neuron-specific enolase (NSE), a specific marker for neuroendocrine cells, is present in normal Merkel cells and can be used as a marker to identify this cell type. In this study, 11 Merkel cell tumors, identified employing electron microscopy, were studied using immunostaining of NSE by the peroxidase-antiperoxidase method. Varying intensities of NSE immunoreactivity were found in the cytoplasm of all the neoplastic cells in the different cases. The uniformly stained cytoplasm formed a small rim surrounding the large, unstained nucleus. Immunostaining of NSE thus provides a simple and reliable method for the differential diagnosis of Merkel cell tumors from other primary skin tumors which, with the exception of some malignant melanomas, have been shown not to contain NSE immunoreactivity.

Aged↗
PubMed1982

Gastro-intestinal and neurohormonal peptides in the alimentary tract and cerebral complex of Ciona intestinalis (Ascidiaceae).

Polypeptide-hormone producing cells were localized in the alimentary tract and cerebral ganglion of Ciona intestinalis using cytochemical, immunocytochemical and electron-microscopical methods. Antisera to the following peptides of vertebrate type were employed: bombesin, human prolactin (hPRL), bovine pancreatic polypeptide (PP), porcine secretin, motilin, vasoactive intestinal polypeptide (VIP), beta-endorphin, leu-enkephalin, met-enkephalin, neurotensin, 5-hydroxytryptamin (5-HT), cholecystokinin (CCK), human growth (GH), ACTH, corticotropin-like intermediate lobe peptide (CLIP) and gastric inhibitory peptide (GIP). Immunoreactive cells were found both in the alimentary tract epithelium and in the cerebral ganglion for bombesin, PP, substance P, somatostatin, secretin and neurotensin. Additionally, in the cerebral ganglion only, there were cells immunoreactive for beta-endorphin, VIP, motilin and human prolactin. 5-HT positive cells, however, were restricted to the alimentary tract. No immunoreactivity was obtained either in the cerebral ganglion or in the alimentary tract with antibodies to leu-enkephalin, met-enkephalin, CCK, growth hormone, ACTH, CLIP and GIP. Prolactin-immunoreactive and pancreatic polypeptide-immunoreactive cells were argyrophilic with the Grimelius' stain and were found in neighbouring positions in the cerebral ganglion. At the ultrastructural level five differently granulated cell types were distinguished in the cerebral ganglion. Granules were present in the perikarya as well as in axons. The possible functions of the peptides as neurohormones, neuroregulators and neuromodulators are discussed.

Adrenocorticotropic Hormone↗
PubMed1981

Neuron-specific enolase is produced by neuroendocrine tumours.

Neuron-specific enolase (NSE) is a neuronal form of the glycolytic enzyme enolase, which was first found in extracts of brain tissue, and was later shown to be present in APUD (amine precursor uptake and decarboxylation) cells and neurons of the diffuse neuroendocrine system but not in other peripheral cells. 90 neuroendocrine neoplasias (APUDomas) (including islet-cell tumours, phaeochromocytomas, medullary thyroid carcinomas, oat-cell tumours, and APUDomas of the gut, pancreas, and lung) reacted strongly with antisera to NSE. In addition, large amounts of the enzyme were found by radioimmunoassay in the tumours (mean 1626 +/- 479 SEM ng of NSE/mg protein), whereas control non-endocrine neoplasias contained less than 15 ng NSE/mg protein. Thus NSE, a specific enzyme produced in the neural and endocrine systems, was found to be produced in considerable quantities by all types of APUDomas but not in any non-endocrine tumours. NSE seems to be a useful and easily detected marker which may be used to distinguish endocrine from nonendocrine neoplasias. Clinical detection of endocrine tumours is difficult and such tumours are often missed. Use of NSE as a marker may avoid this.

Apudoma↗
PubMed1980

Enkephalin-, VIP- and substance P-like immunoreactivity in the carotid body.

The carotid body type I cell contains amines and has features, both morphological and cytochemical, which indicate that it may also produce a peptide. Many regulatory peptides are now known to be present in both central and peripheral tissues. In the periphery these neuropeptides occur in both classical endocrine (APUD) cells and the neurones of the autonomic nervous system. We have now investigated the possible presence of neuropeptides in the cat carotid body using both immunocytochemistry and radioimmunoassay. Met- and Leu-enkephalin-like material occurred in considerable quantities in carotid body extracts and enkephalin-like immunoreactivity was localised in type I cells. Both vasoactive intestinal polypeptide (VIP)- and substance P-like immunoreactivity was also present but was localised in nerve fibres distributed throughout the organ. These active neuropeptides are widely distributed in mammalian tissues, forming a diffuse regulatory system which now seems to include the carotid body.

Animals↗
PubMed1980

Familial pheochromocytoma and islet cell tumor of the pancreas.

The occurrence of pheochromocytoma(s) or pancreatic islet cell tumor(s), or both, in two or more members of three unrelated families in a manner consistent with autosomal dominant inheritance suggests that this tumor association is a genetically determined syndrome. Among 11 affected patients (aged five to 53 years), 10 had pheochromocytoma (bilateral in six), four had islet cell tumor (multicentric in one), and three had both tumors. Clinical presentation was due to pheochromocytoma in 10 cases (symptoms or signs commencing before age 10 years in three patients) and islet cell carcinoma in one case. Four patients are dead as a result of the tumors--two from pheochromocytoma and two from islet cell carcinoma.

Adenoma, Islet Cell↗
PubMed1980

The common peptides and the cytochemistry of their cells of origin.

Thirtyfive biologically active peptides are products of the 40 cells of the APUD series, which constitute the Diffuse Neuroendocrine System (DNES). Twentyone of these peptides are found not only in the cells and processes of the DNES but also in the cells and the processes of the nervous system. Hence the appellation common. To the seven original common cytochemical features of the APUD cells it is possible to add the positive results of 3 subsidiary staining techniques (Lead haematoxylin, Argyrophilia, Formaldehyde-Fluorescamine), a singly cytochemical method (Formaldehyde-ozone), and an immunocytochemical molecular marker method (neuron-specific enolase; NSE). Application of this last method demonstrates NSE in the APUD cells and confirms their origin from "neuroendocrine-programmed epiblast."

APUD Cells↗
PubMed1979

Peptide hormone-like immunoreactivity in the gastrointestinal tract and endocrine pancreas of eleven teleost species.

The distribution of peptide hormone-like immunostaining in the gastrointestinal tract of 11 teleost species was investigated by immunofluorescence. Cells immunoreactive for somatostatin were found in the glandular epithelium of the stomach of four species and in the epithelium of the pyloric appendage of one species. The mid-gut epithelium contained cells reactive with antibodies to glucagon (three species), gastrin (five species), pancreatic polypeptide (five species), and substance P (two species). Cells immunoreactive for met-enkephalin were found in the epithelium of both the mid-gut and the stomach of six species. In six species in which the endocrine pancreas was investigated, insulin-, glucagon-, and somatostatin-like immunoreactivity was observed. Pancreatic polypeptide was definitely localised by immunostaining in cells of the endocrine pancreas of only one out of three species examined. Vasocative intestinal polypeptide-, neurotensin-, bombesin-, and enkephalin-like immunoreactivity was identified in the gastrointestinal nerve fibres in various species. In view of the considerable species variation found, caution should be exercised in generalising about the peptides present in the gastrointestinal tract of fish.

Animals↗