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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Morphologic studies of pituitary neoplasms removed by srugery from 36 human patients revealed 8 chromophobe adenomas which differed clearly from the remaining tumors. The cytoplasm of the adenoma cells failed to stain with PAS, aniline blue, adehyde fuchsin, aldehyde thionin, orange G or light green, but positively stained granules were found by using erythrosine or carmosine. Immunoperoxidase technique disclosed the presence of prolactin in the cytoplasm of some adenoma cells. The adenoma cells exhibited distinct ultrastructural features such as well developed rough surfaced endoplasmic reticulum with Nebenkern formation, prominence of Golgi apparatus, presence of misplaced exocytosis as well as pleomorphism of secretory granules with a considerable variation of size ranging from 130 to 500 nm in diameter. Thus, by electron nicroscopy the adenoma cells showed a close resemblance to prolactin cells of the non-tumouous pituitary glands except for the reduced size and number of secretory granules. Thes chromophobe adenomas are regarded as representing a distinct pathological entity clearly distinguishable from other forms of pituitary neoplasms. In view of the morphologic findings and the elevation of blood prolactin level (measured in 3 patients) the term, "sparsely granulated prolactin producing pituitary adenoma", appears to be the most appropriate one to designate these tumors.
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PMID:Pituitary chromophobe adenomas consisting of prolactin cells: a histologic, immunocytological and electron microscopic study. 4 6

Light and electron microscopical examination of a pituitary adenoma showed that the tumor was composed of prolactin cells that produced amyloid-like material. The findings have been interpreted in favor of the role of rough endoplasmic reticulum in amyloid fibril formation within the adenoma cells. Histochemical and fine structural data indicate that the material produced by this tumor resembles apudamyloid rather than immunoamyloid.
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PMID:Pituitary adenoma producing amyloid-like substance. 5 61

85 surgically removed pituitary adenomas were studied by light and electron microscopical and in part immunohistochemical methods. The tumors were histogically classified and reexamined by the ultrastructure. Histochemically the adenomas could be differentiated in acidophil adenomas (1. group, 41%), mucoid cell adenomas (2. group, 6%), and chromophobe adenomas (3. group, 37%) whereas oncocytic adenomas (4. group, 16%) could be identified only in plastic-embedded sections. About half of the acidophil adenomas were highly differentiated and showed structures which correspond to those of normal STH cells (subgroup 1.1). 1 adenoma consisted of cells of prolactin type (subgroup 1.2). The other acidophil adenomas were differentiated to a lower degree and showed no resemblance to the structures of normal acidophil cells. The 5 mucoid cell adenomas were proved to be with all methods highly differentiated adenomas of ACTH-cell type (subgroup 2.1). TSH-cell adenomas (subgroup 2.2) and lower differentiated mucoid cell adenomas (subgroup 2.0) were lacking in our collection. More than one third of the chromophobe adenomas showed well developed endoplasmic reticulum and Golgi complexes. The other had little and small organellas that resemblances to immature stem cells were evident. The oncocytic adenomas were identified in plastic-embedded sections by their fine-granular structures which were based ultrastructurally not on small secretory granules but on closely arranged mitochondrias.
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PMID:[Light and electron microscopic studies for classification of pituitary adenomas (author's transl)]. 12 39

Adenomata taken from nine patients with Cushing's syndrome were observed by electron microscopy. Agranular endoplasmic reticulum was prominently developed in all cases, occasionally fine dotty granules were observed in the tubules of agranular endoplasmic reticulum. Mitochondria showed a wide variety of changes in size, shape and internal structure, and somtimes contained electron dense droplets in their matrix. Mitochondria resembling those in the normal zona fasciculata intermingled with pathologically altered ones, suggesting that the adenomata which caused Cushing's syndrome were derived from the zona fasciculata. Fibrous structures were seen in the cytoplasm in one case. It is proposed that all of the changes in cellular organelles of the adenoma cells are correlated with increased secretory activity.
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PMID:Fine structure of adrenal adenomata causing Cushing's syndrome. 14 86

Adenomata taken from 25 patients with primary aldosteronism were observed by electron microscopy. The cells in the adenoma had a well developed agranular endoplasmic reticulum but granular endoplasmic reticulum was not prominent. Most of the mitochondria resembled those in the cells of the zona glomerulosa, suggesting that the adenomata which caused primary aldosteronism are derived from this zone. Spironolactone bodies were found in the cells of the adenoma from a patient who received spironolactone. Their appearance was identical to that described in previous reports.
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PMID:Adrenal adenomata causing primary aldosteronism. An ultrastructural study of twenty five cases. 15 48

Fenestrae were found in freeze-fractured cisternae of the Golgi apparatus and endoplasmic reticulum of glioblastoma, oligodendroglioma, ependymoma, medulloblastoma, medulloepithelioma, meningioma, cerebellar sarcoma, hemangioblastoma, and chromophobe adenoma. They were about 200--400 A in diameter and often diffusely distributed or concentrated in groups in Golgi cisternae, while they were around 300--600 A in size and scattered in distribution in cisternae of endoplasmic reticulum. They appeared as conical protrusions or circular broken-off necks of face A and as circular holes on face B in tangential fractures, and as several constrictions of cisternae in cross fractures.
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PMID:Fenestrae in golgi and endoplasmic reticulum cisternae of human brain tumours. 16 55

Spironolactone bodies were observed in an adrenal cortical adenoma that was removed from a patient with primary hyperaldosteronism (Conn syndrome) treated preoperatively with spironolactone. The electron microscopical evaluation of this adrenal cortical adenoma shows origin of spironolactone bodies from whorls of endoplasmic reticulum in cells with the cytoplasmic features of those from the zona glomerulosa of the adrenal gland. There was no evidence that the bodies were derived from mitochondria, which confirms recent ultrastructural findings in patients treated with spironolactone. These bodies have been described in the adrenal cortex only in patients who have received spironolactone, and the pharmacologic specificity of the bodies strongly suggests a direct mode of action by spironolactone on aldosterone production by cells of the adrenal zona glomerulosa.
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PMID:Spironolactone bodies in an adrenal adenoma. 16 3

The ultrastructure of the adrenal cortex was studied by quantitative stereologic techniques in LAF1 mice bearing a transplantable, ACTH-secreting pituitary tumor (AtT). The tumor stimulated a significant increase in volume and surface area of smooth endoplasmic reticulum and mitochondrial membranes in all three zones of the adrenal cortex. Concomitantly, plasma corticosterone was increased significantly in tumor-bearing animals. The AtT was an adenoma of the chromophobe type. Continuity of the nuclear membrane with the rough endoplasmic reticulum was readily observed in tumor parenchymal cells.
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PMID:Quantitative study on the effect of an ACTH-producing pituitary tumor on the ultrastructure of the mouse adrenal gland. 16

Virus-like particles were observed in the giant cells of a mammary adenoma of a snow leopard kept in captivity. Particles that measured 115 to 125 nm in diameter budded from the lamella of endoplasmic reticulum and were studded on their inner surfaces with dense granules (approximately 12 nm) that gave them their unique ultrastructural morphology. Such particles were not observed extracellularly. Type B or type C particles were not seen in the tumor tissue.
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PMID:Virus-like particles in cystic mammary adenoma of a snow leopard. 17 Oct 61

The fine structural morphologic features of a microfollicular thyroid adenoma from a 28 year old female were examined. Although the patient had been laking exogenous thyroxine therapy for 14 months, the morphology of the adenoma was characterized by numerous small to medium sized follicles composed of metabolically active, well differentiated columnar cells with numerous colloid droplets, dilated granular endoplasmic reticulum, large numbers of coated vesicles and lysosomes, large colloid containing "lakes," microtubules, microfilaments, and prominent apical microvillous projections. Of special inetrest were small spherical psammomatous calcospherites ecountered in histiocytes and the interstitium. Also noteworthy were ropelike configurations observed in most of the follicular lumina. Structural-functional correlations and potential origins of psammoma bodies and calcospherites are discussed.
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PMID:Fine structural studies of a human thyroid adenoma, with special reference to psammoma bodies. 19 47


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