Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A bronchial carcinoid with globular intracytoplasmic inclusions is reported. The inclusions stain brown with Grimelius silver impregnation and some show distinct immunoreactivity for chromogranin A. Tumour cells stain positively with antisera to neuron specific enolase, chromogranin A and not with antisera against ACTH, somatostatin or S-100 protein. The cells show distinct immunoreactivity for cytokeratins and vimentin, which is particularly intense in the intracytoplasmic inclusions. Desmin and glial fibrillary acidic protein are absent. Ultrastructural analysis reveals that the inclusions are composed of aggregates of filaments of 8-10 nm of diameter, intrapping a few neurosecretory granules. Immunohistochemical and ultrastructural data support the hypothesis that the inclusions are composed of intermediate filaments, whose metabolism and synthesis have somehow been deranged.
 ...
PMID:Bronchial carcinoid with paranuclear fibrillary inclusions related to cytokeratins and vimentin. 247 31

A case of gangliocytic paraganglioma (GP) of the ampulla of Vater is reported and the literature reviewed, with special attention to immunohistochemical studies. The present case, which occurred in a 56-year-old woman, shows the typical histological admixture of epithelioid, ganglion and spindle cells. Immunohistochemistry reveals strong reactivity for synaptophysin, Leu-7, somatostatin, S-100 protein and vimentin. A few ganglion cells are reactive for neurofilaments. Chromogranin A, myelin basic protein, desmin and cytokeratin are absent. Immunohistochemical data from literature regarding the cytoskeletal composition of GPs are not unequivocal: cytokeratin and neurofilament positivity is reported by some authors and denied by others. More uniformity is reported concerning the peptides produced by GPs: somatostatin and pancreatic polypeptide are the most frequently found antigens, followed by serotonin. General neuroendocrine markers like neuron specific enolase and protein gene product 9.5 are always positive, whereas chromogranins are rarely found. S-100 protein is always positive in the spindle cell component. Our data are in keeping with those previously reported and add the diffuse positivity for the Leu-7 antigen and the positivity of ganglion cells for synaptophysin. The nature of the tumour is still a matter of debate and it is difficult to agree with either of the proposed hypotheses--hamartoma/choristoma versus true neoplasm. However the recent reports of the occasional malignant evolution of GPs may support their true neoplastic nature.
 ...
PMID:Duodenal gangliocytic paraganglioma. Report of a case and review of the literature. 247 67

We examined the effect of non-neuronal cells on somatostatin release from cultured cerebral cortical cells. Three culture models were used: (1) neuron-enriched cultures obtained from cortex of 17-day-old rat embryos and exposed to 10 microM cytosine arabinoside (Ara C) for 48 h between days 3 and 5 after plating; (2) whole cell cultures obtained by using the same protocol but untreated with Ara C; (3) glial primary cultures obtained from newborn rats. We studied: (i) the cellular composition of the cultures by using two astroglial markers: vimentin and glial fibrillary acidic protein (GFAP); (ii) the spontaneous and forskolin-stimulated somatostatin release. In 8-day-old cultures morphological data revealed that Ara C treatment reduced glial cells to 6%. At 7 and 10 days of culture somatostatin spontaneously released from Ara C-treated cells was higher than that measured from untreated cells. On the 17th day of culture, neuron-enriched cultures contained a lower amount of somatostatin than whole cell cultures. Forskolin elicited a dose-dependent release of somatostatin from whole cell cultures, but had no effect on neuron-enriched cultures. Astroglial released media (ARM) from glial primary cultures exposed to forskolin for 20 min induced somatostatin release from neuron-enriched cultures. HPLC analysis of endogenous amino acids of ARM showed that glutamate, glutamine, glycine and alanine were significantly increased after forskolin stimulation. Our results suggest a functional interaction between glial cells and neurons secreting somatostatin.
 ...
PMID:The presence of non-neuronal cells influences somatostatin release from cultured cerebral cortical cells. 289 72

Neuroendocrine (NE) neoplasms of the human bronchopulmonary tract were examined by electron microscopy, immunocytochemistry, and gel electrophoresis of cytoskeletal proteins from microdissected tissue samples. All samples (carcinoids, well-differentiated NE carcinoma, NE carcinomas of intermediate type, NE carcinomas of the small cell type) contained significant numbers of cells that immunostained for one or more of the following neuroendocrine markers tested: bombesin, calcitonin, ACTH, leu-enkephalin, gastrin, serotonin, somatostatin, alpha-melanocyte-stimulating hormone, vasoactive intestinal peptide, glucagon, insulin, substance P, and neuron-specific enolase. Electron microscopy revealed typical NE cell features, including variable abundant and frequently heterogeneous neurosecretory granules. Tumor cells contained filaments specifically stained with different conventional and monoclonal antibodies to cytokeratins and displayed punctate plasma membrane staining with antibodies to desmoplakins, in agreement with the electron microscopic demonstration of tonofilament bundles and desmosomes. Immunocytochemistry for NE markers and cytoskeletal proteins on consecutive sections revealed both cytokeratins and neuroendocrine substances in single cells. Using gel electrophoresis of cytoskeletal proteins of tissue regions extracted with high salt buffer and detergent, we could detect, in the tumors tested, appreciable amounts of cytokeratin polypeptides 8, 18, and 19, i.e., major cytokeratins also found in certain other lung carcinomas such as adenocarcinomas. Tumor cells were not significantly stained with antibodies to other intermediate filament proteins such as vimentin, desmin, glial filament protein, and neurofilament protein. The results show that NE substances can be synthesized in cells containing a typical epithelial cytoskeleton, i.e., cytokeratin filaments and desmosomes. These findings support the notion of an epithelial character of these tumors and appear in contrast with recent reports that neurofilaments are the only type of intermediate filaments present in carcinoids and other pulmonary NE tumors. These observations may have important implications for the histogenesis of NE carcinomas and for diagnostic pathology.
 ...
PMID:Coexpression of neuroendocrine markers and epithelial cytoskeletal proteins in bronchopulmonary neuroendocrine neoplasms. 298 72

A case of a primary carcinoid tumor of the testis which occurred in a 57-year-old man is reported. The patient was treated by orchiectomy, and no clinical features of a carcinoid syndrome had been noted. The tumor measured 4.0 X 3.2 X 2.0 cm in size and was yellowish in color. Histochemically, the tumor cells were composed in part of argentaffin and in part of argyrophil. Immunohistochemically, the argentaffin tumor cells were positive for neuron-specific-enolase. No tumor cells were positive, however, for neurofilaments, vimentin, keratin, desmin, GFAP, S-100 protein, ACTH, and somatostatin. Electronmicroscopy revealed numerous neurosecretory granules. Tumorous tissue presented a histomorphology of a pure carcinoid tumor composed of parts of argentaffin and argyrophil.
 ...
PMID:[A case of primary carcinoid tumor of the testis]. 318 66

Three cases of clinically benign pancreatic papillary cystic tumors in young female patients were studied by immunohistochemistry and electron microscopy in order to define the cellular nature of this type of neoplasm. Two of the tumors showed focal cytokeratin- and desmoplakin-positivity as evidence of focal epithelial differentiation, while the tumor cells were in all cases positive for vimentin--the intermediate filament protein typical of (but not specific for) mesenchymal cells. Electron microscopy showed some cell-cell junctions, but there was no evidence of acinar or islet cell differentiation. The tumors were at least focally positive for neuron-specific enolase, and small clusters of polypeptide hormone immunoreactive cells were present in all cases (glucagon 3/3, somatostatin 2/3, insulin 2/3). However, the tumors were negative for synaptophysin and neurofilament proteins, unlike most islet cell tumors. Trypsin and chymotrypsin immunoreactivity was found in all tumors, but because many nonpancreatic carcinomas were also positive, we doubt whether these two enzyme proteins can act as specific markers for pancreatic acinar cell differentiation. Two of the tumors that were studied immunohistochemically for the presence of nuclear estrogen receptors, were negative. Therefore no proof of the suggested hormone dependence of this tumor could be obtained. We conclude that papillary cystic tumor is a neoplasm of primitive pancreatic epithelial cells, that may exhibit focal endocrine cell differentiation.
 ...
PMID:Papillary cystic tumor of the pancreas. An analysis of cellular differentiation by electron microscopy and immunohistochemistry. 367 83

Functional in vitro studies with isolated gastric mucosal cells require cytological identification of different cell types in suspension or primary culture. Since suitable techniques have not been well established, different staining methods for the discrimination of dispersed pig and guinea pig gastric cells have been developed on the basis of modified previous protocols for enzymatic cell dispersion. Chief and parietal cells were visualized by combined periodic acid-Schiff stains. Surface mucous and mucous neck cells were identified by affinity-labelling, using lectins with selective staining properties in situ. Two of the lectins were found to be specific markers for gastric polymorphonuclear cells. The following vital tests were found to be useful: succinic dehydrogenase for parietal cells, Nile blue/brilliant cresyl blue stains for chief cells, and different phagocytosis assays for endothelial cells and gastric phagocytes. Endocrine cells were characterized by immunocytochemistry using specific antibodies against gastrin, somatostatin, histamine and serotonin. The same technique using a vimentin antibody was performed for the identification of fibroblasts. Proliferation of mucosal cells in primary culture was monitored by the incorporation of bromo-deoxyuridine, which was subsequently detected by a monoclonal antibody.
 ...
PMID:Isolation, identification and quantitative evaluation of specific cell types from the mammalian gastric mucosa. 750 19

Polysialic acid (PSA) is abundant on growing axons during brain development and down regulated on maturation. However, high amounts of this carbohydrate polymer have been found to persist in some regions of the adult rat brain including the mediobasal hypothalamus. In this study, confocal laser scanning microscopy combined with double fluorescence immunostaining was used to characterize the cellular localization of PSA throughout the median eminence and neurointermediate hypophysial lobe of adult rats. In these regions, polysialic acid-immunoreactivity (PSA-IR) generally appeared associated with fiber-like structures. Double immunostaining experiments demonstrated that, in addition to large axons of the neural lobe immunoreactive to vasopressin or oxytocin, PSA was constantly associated with fibers projecting into the intermediate hypophysial lobe immunoreactive to either gamma-aminobutyric acid (GABA) or tyrosine hydroxylase. Similarly, PSA-IR was detected on most, but not all the fibers immunoreactive to GABA or tyrosine hydroxylase dispersed throughout the neural lobe and the different layers of the median eminence. On the other hand, no PSA-IR was detected on axons immunoreactive to somatostatin or to corticotropin releasing hormone projecting throughout the median eminence, or on glial cell bodies and processes immunoreactive for glial fibrillary acidic protein (GFAP) or for vimentin dispersed throughout the median eminence and the neural lobe.
 ...
PMID:Immunolocalization of polysialic acid in the median eminence and neurointermediate hypophysial lobe of adult rats. 789 19

Cells displaying highly condensed pyknotic nuclei, the most characteristic feature of apoptosis, are considered as dead cells in neural tissue. The present study aimed to devise methods that could allow the neurogenetic and phenotypic characterization of dying pyknotic cells. In the first set of experiments, pregnant mice were labeled at embryonic days E10-E16 with pulses of 5'-bromodeoxyuridine visualization of BrdU after an immunoperoxidase reaction. In addition to normal, healthy immunopositive nuclei, these preparations displayed a number of pyknotic nuclei that were immunoreactive for BrdU. Both the regional and the temporal distribution of BrdU-positive pyknotic cells were coincidental with the peaks of dead cells in neural tissue. For example, pulses of BrdU at E10-E11 resulted in the visualization of immunoreactive pyknotic cells in the subplate and white matter of the cerebral cortex in early postnatal (P) animals. Thus, the times of generation (birthdates) of cells subjected to degenerative processes can be unequivocally identified. In the second set of experiments, brain sections from unlabeled littermates were immunostained for a variety of neural and glial markers and counterstained with bisbenzimide, to find antigens which, by being present in degenerate pyknotic cells, could indicate the phenotype of such cells. Although no pyknotic cells were positively immunostained for neurofilaments, neuropeptide Y, somatostatin, vasoactive intestinal polypeptide, or vimentin, a number of pyknotic cells were found to be immunoreactive for microtubule-associated protein 2, gamma-aminobutyric acid, calbindin 28KD, and glial fibrillary acidic protein. The percentage of pyknotic cells labeled with neural antigens accounted for more than 20% of the total number of pyknotic cells in a given brain region. In contrast, GFAP-positive pyknotic cells represented up to 50% of the total pyknotic cell population. The method shown here has enabled us to determine that both neurons and glial cells undergo degeneration during normal development.
 ...
PMID:Characterization of the phenotype and birthdates of pyknotic dead cells in the nervous system by a combination of DNA staining and immunohistochemistry for 5'-bromodeoxyuridine and neural antigens. 831 74

The cellular nature of the giant eosinophilic cells of tuber and of the cells comprising subependymal giant cell astrocytoma (SEGA) in tuberous sclerosis (TS) remains unclear. To assess the characteristics of these lesions, 13 tubers and 6 SEGA were immunohistochemically studied with glial and neuron-associated antigens. In addition to conventional ultrastructure, 6 tubers and 8 SEGA were subjected to immunoelectron microscopic study for glial fibrillary acidic protein (GFAP) and somatostatin. Eosinophilic giant cells of tubers were positive for vimentin (100%), GFAP (77%) and S-100 protein (92%); such cells were also found to a various extent to be reactive for neuron-associated antigens, including neurofilament (NF) proteins (38%) or class III beta-tubulin (77%). SEGA also showed variable immunoreactivity for GFAP (50%) or for S-100 protein (100%); NF epitopes, class III beta-tubulin, and calbindin 28-kD were expressed in 2 (33%), 5 (83%) and 4 (67%) cases, respectively. Cytoplasmic staining for somatostatin (50%), met-enkephalin (50%), 5-hydroxytryptamine (33%), beta-endorphin (33%) and neuropeptide Y (17%) was noted in SEGA, but not in tubers. Ultrastructurally, the giant cells of tubers and the cells of SEGA contained numerous intermediate filaments, frequent lysosomes and occasional rectangular or rhomboid membrane-bound crystalloids exhibiting lamellar periodicity and structural transition to lysosomes. Some SEGA cells showed features suggestive of neuronal differentiation, including stacks of rough endoplasmic reticulum, occasional microtubules and a few dense-core granules. Furthermore, in one case of tuber, a process of a single large cell was seen to be engaged in synapse formation. Intermediate filaments within a few cells of both lesions were decorated by gold particle-labeled GFAP antiserum. Within the tumor cells of SEGA, irregular, non-membrane-bound, electron-lucent areas often contained somatostatin-immunoreactive particles, whereas the latter could not be detected in tuber. The present study provides further evidence of divergent glioneuronal differentiation, both in the giant cells of tubers and the cells of SEGA. The findings of similar cells at different sites, including the subependymal zone, white matter ("heterotopias"), and cortex indirectly supports the idea that these lesions of TS result from a migration abnormality.
 ...
PMID:Tuber and subependymal giant cell astrocytoma associated with tuberous sclerosis: an immunohistochemical, ultrastructural, and immunoelectron and microscopic study. 854 29


<< Previous 1 2 3 4 5 Next >>