Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 64 year old woman had been on lithium carbonate for 12 years for manico-depressive psychosis. Mild asthenia leads to the diagnosis of primary hyperparathyroidism based on the findings of hypercalcemia up to 2.85 mmol/l inappropriate levels of parathormone and a non-suppressive rise of nephrogenic cyclic AMP. These symptoms were not relieved by removal of a chief cell adenoma of the left inferior parathyroid; surgical reexploration leads to the removal of an adenoma in a high, ectopic situation. Further venous samplings were collected during cervico mediastinal phlebography because of persistent hypercalcemia: parathormone levels were high in a thymic vein and a new cervicotomy revealed a fifth gland with an adenoma in the high mediastinum. After removal of the third adenoma, the patient became hypocalcemic. Lithium was not discontinued according to the patient's wishes. Eighteen months later she was well and normocalcemic on alfacalcidol therapy. Multiple adenomas of the parathyroids are rare (1.7 p. 100 to 5 p. 100) and the recurrence of an adenoma on a supernumerary gland is exceptional. Eighteen clinical cases of primary hyperparathyroidism under lithium therapy have been reported, but mild asymptomatic hypercalcemia with inappropriate increased parathormone levels seems to be more common. Duration of treatment is very variable: 1 day to 12 years, and serum calcium levels or up to 3.9 mmol have been observed. Ten patients underwent cervicotomy with removal of an adenoma 6 of them remaining under treatment, with 2 recurrences in our case. Five of the 8 non-operated patients remained on lithium therapy and showed mild hypercalcemia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Multiple hypersecreting lesions of the parathyroid glands during treatment with lithium]. 371 17

"Cold" thyroid nodules do not concentrate (131)I before or after thyrotropin (TSH) administration. In an attempt to elucidate the reason for this TSH unresponsiveness, the effect of TSH in vitro on several metabolic parameters was studied in 11 "cold" thyroid adenomas, 2 medullary carcinomas, and in the surrounding normal thyroid tissue. Basal adenyl cyclase activity, glucose-1-(14)C oxidation, and (32)P incorporation into phospholipids were significantly greater in the adenomas than in the adjacent normal thyroid; basal cyclic 3',5'-adenosine monophosphate (cyclic AMP) concentration and adenine-(3)H incorporation into (3)H-labeled cyclic AMP were not different. In adenomas as well as normal thyroid, all parameters responded significantly to in vitro TSH stimulation. The response to TSH of adenyl cyclase activity and (32)P incorporation was enhanced in adenomas compared with that of the adjacent normal thyroid. These differences were not explained by an increased cellularity of the adenomas. Medullary carcinomas did not respond to TSH in any of the above parameters. The studies demonstrate an intact, TSH-responsive adenyl cyclase-cyclic AMP system in the adenomas and, accordingly, imply the presence of receptor sites for TSH on the cells of the adenoma. The failure of such nodules to concentrate (131)I may be owing to a subsequent impairment in the expression of cyclic AMP action on iodine metabolism.
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PMID:Effects of thyroid-stimulating hormone on adenyl cyclase activity and intermediary metabolism of "cold" thyroid nodules and normal human thyroid tissue. 434 2

The present studies were performed in order to analyze the incorporation of 3H-uridine into RNA and its hormonal regulation as well as the content of total iodine, T3, T4, RNA, DNA and protein in normal and abnormal human thyroid obtained at surgery. The content of protein, RNA and DNA is not significantly changed in follicular adenoma and in adenomatous goiter, RNA labeling from 3H-uridine showed similar values in slices from normal and abnormal glands. TSH and cyclic AMP increased the labeling of RNA in normal tissue but had no effect in the follicular adenoma and adenomatous goiter. A significant decrease in total iodine, T3 and T4 concentration was found in the pathological samples when compared to normals. The present results would suggest that in these patients the biochemical abnormalities lie at a step distal to the TSH receptor and the adenylate cyclase.
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PMID:Studies on the regulation of RNA labeling and on the biochemical constituents of normal and abnormal human thyroid. 608 10

Sixty patients with persistent or recurrent primary hyperparathyroidism underwent reexploration during which urinary cyclic adenosine monophosphate (UcAMP) levels were determined at half-hour intervals by radioimmunoassay. Retrospective analysis of the data allowed us to develop UcAMP criteria for surgical success. Following removal of parathyroid tissue, if an individual UcAMP level dropped 50% from the median baseline level, or if elevated levels dropped to less than 4.0 nmol/dl glomerular filtrate, surgery was predicted to be successful. Eight unsuccessful procedures in seven patients produced no decline in UcAMP, and the intraoperative results accurately predicted surgical failure. Fifty-three patients underwent successful procedures and in every case UcAMP fell. Ninety-eight per cent of these successful procedures were predicted by our criteria. Levels of UcAMP fell 1.5 +/- 0.5 hours (means +/- SD) following abnormal parathyroidectomy. In 19 of 36 successful cases diagnosed before surgery as adenoma, the operative procedure was terminated before a significant drop in UcAMP. In 16 of 17 successful cases diagnosed before surgery as hyperplasia or uncertain histology, UcAMP fell during the operation. Intraoperative determination of UcAMP is helpful in reoperative parathyroid surgery. The criteria established allow intraoperative prediction of success with remarkable accuracy. Urinary cyclic AMP is especially helpful in reoperation for multigland disease; when enough pathologic tissue has been removed, the criteria will be met and the procedure may be terminated with confidence.
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PMID:Intraoperative urinary cyclic adenosine monophosphate as a guide to successful reoperative parathyroidectomy. 609 73

A 48-year-old man with typical clinical and biochemical features of primary aldosteronism was revealed on operation to have two adrenocortical adenomas in the left gland. An ACTH-dependent pattern of aldosterone secretion was demonstrated in terms of the parallel circadian rhythm of aldosterone with cortisol and the exaggerated response to ACTH but not to angiotensin II. Aldosterone and cyclic AMP release in vitro was studied using collagenase-dispersed cells of each adenoma. Not only the large adenoma but the small one showed basal and ACTH-stimulated releases of aldosterone greater than those by the adjacent tissue. In response to angiotensin II and potassium, the small adenoma showed a larger maximum increment of aldosterone than the large adenoma. This difference in endocrine features of the two adenomas suggests a possible transformation in their nature during development. An exaggerated cyclic AMP release by the adenomas in response to ACTH in vitro suggested the possible role of increased adenylate-cyclase activity in the hyperresponse of aldosterone to ACTH in this case.
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PMID:Endocrine characterization of the adrenal adenomas in a case of primary aldosteronism. 610 Apr 5

The availability of accurate and inexpensive methods for measuring serum calcium levels has resulted in a rapid increase in the number of diagnoses of primary hyperparathyroidism, notably in its asymptomatic hypercalcemic forms. In addition, the development of a radioimmunoassay of the parathyroid hormone and, more recently, measurements of nephrogenous cyclic AMP during fasting and after calcium loading have led to the recognition of clinical variants of the disease, such as intermittent or borderline hypercalcemia and pure hypercalciuria with normal calcemia. The degree of hypercalcemia in stable primary hyperparathyroidism depends on renal tubular reabsorption of calcium rather than on bone resorption. The poor correlation observed between calcium tubular reabsorption rate and magnitude of parathyroid hormone hypersecretion suggests that as yet undetermined factors interfere with the effects of parathyroid hormone on renal tubules and probably account for the fluctuations in calcemia reported during serial determinations in patients. The sigmoid relationship between parathyroid hormone release and extracellular calcium concentrations has been analyzed from recent in vitro studies with dispersed parathyroid cells. In primary hyperplasia of the parathyroid glands hypersecretion of parathyroid hormone seems to depend principally upon the increase in tissue mass with normal sensitivity to calcium at cellular levels, whereas in adenoma the primary abnormality responsible for hypersecretion of parathyroid hormone would be an alteration in cell sensitivity to calcium, as indicated by an elevated "set point". Finally, while complicated primary hyperthyroidism requires surgery, our limited knowledge of the natural history of asymptomatic forms makes it impossible to decide which of these patients will ultimately need to be operated upon.
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PMID:[Present status of primary hyperparathyroidism]. 623 8

A follicular adenoma of the thyroid was 'hot' one hour after 99mTc pertechnetate administration, but 'cold' 24 h after 131I iodide administration. Incubation of the tissue in vitro demonstrated a defect in iodide binding to proteins that was abolished by addition of an H2O2 generating system. In this tissue iodide failed to inhibit TSH-induced cyclic AMP accumulation. The results show that iodide oxidation is required for its inhibitory action on cyclic AMP accumulation in human thyroid.
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PMID:Iodide organification defect in a cold thyroid nodule: absence of iodide effect on cyclic AMP accumulation. 632 51

Between July 89 and June 92, 70 patients with primary hyperparathyroidism underwent adenomectomy by unilateral incision under local anesthesia (Ul/LA), without exploration of the remaining glands. The procedure was carried out with intraoperative monitoring of urinary cyclic AMP (n = 35), Calcemia was measured 6-monthly for one year in every patient. 62 (88.6%) patients were cured after Ul/LA, whereas 5 patients required conversion to bilateral cervicotomy under general anesthesia because of abnormal hormonal levels, thus giving an overall success rate of 97% (67/70). The reasons for treatment failure of Ul/LA included misleading conclusions of cervical ultrasonography (n = 5), agitation of the patient (n = 1) and deep localization of the adenoma (n = 1). When cervical ultrasonography is suggestive of a parathyroid adenoma in expert hands, the probability of a second localization or associated hyperplasia is very low, so that adenomectomy by Ul/LA can be attempted safely, provided that the serum level of intact parathyroid hormone returns to normal values within one hour following resection. In our experience, parathyroidectomy by Ul/LA should not be considered in case of non conclusive ultrasonography, familial history pf hyperparathyroidism of MEN-I, ultrasonic evidence of several enlarged glands or associated thyroid nodule requiring simultaneous treatment.
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PMID:[Surgery of primary hyperparathyroidism by unilateral approach under local anesthesia and intraoperative determination of PTH 1-84]. 785 82

A rare case of benign retroperitoneal schwannoma in a 47-year-old female is reported. She was initially diagnosed to have an adrenal tumor at the Prefectural Cancer Center Hospital and was subsequently admitted to this hospital. When she was admitted, she was diagnosed as undergoing a hypercalcemic crisis (s-Ca 9.2mEq/l). Serum intact-PTH was elevated, but urine cyclic-AMP and % TRP were almost normal. Gd-DTPA enhanced T1 weighted MRI showed a hyperintensity area between the trachea and the thyroid. A parathyroid tumor and a retroperitoneal tumor were excised completely. The final pathological diagnoses were determined to be a parathyroidal adenoma and a retroperitoneal Schwannoma. After a 6-month follow-up period no recurrence and no electrolytic imbalance were detected and the patient presently displays no further symptoms.
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PMID:[A case of retroperitoneal schwannoma associated with primary hyperparathyroidism]. 812 23

A tumour of the left adrenal gland was identified in a woman who presented with virilization and secondary amenorrhea. Preoperatively, the plasma levels of dehydroepiandrosterone sulphate, dehydroepiandrosterone, androstenedione, testosterone, 5 alpha-dihydrotestosterone and 5-androstene-3 beta,17 beta-diol were elevated two- to fourfold whereas those of urinary 17-ketosteroids were elevated more than tenfold. The production rate of dehydroepiandrosterone sulphate was more than 16 times that in normal women whereas those of dehydroepiandrosterone, testosterone and androstenedione were approximately twofold greater; plasma testosterone was derived almost entirely from the peripheral conversion of androstenedione. Blood was obtained by catheterization of the ovarian veins, left adrenal gland vein and inferior vena cava (at two different sites) and plasma steroid levels were determined: testosterone and cortisol levels were elevated in all blood samples whereas those of androstenedione, dehydroepiandrosterone sulphate and 11-desoxycortisol were approximately six- to eightfold, 1.5-fold and nine- to 22-fold higher in the effluent on the left adrenal gland/tumour compared with the levels in the other compartments. Blood was collected hourly for 24 h to determine steroid levels under basal conditions and, also, after ACTH treatment. Plasma cortisol levels increased markedly upon ACTH administration and fell to very low levels 11 h later, but those of androstenedione, testosterone, dehydroepiandrosterone, 5-androstene-3 beta,17 beta-diol and dehydroepiandrosterone sulphate were not affected by ACTH treatment. A histological diagnosis of cortical adenoma of the extirpated tumour was made. Tissue explants and adenoma cells were maintained in culture to characterize the steroid-metabolizing properties of the tumour. The secretion of dehydroepiandrosterone sulphate by tissue explants was highly initially, but declined to almost undetectable levels after 5 days in culture. In the presence of ACTH, dehydroepiandrosterone sulphate secretion remained elevated throughout the entire study up to 5 days. Basal secretion of dehydroepiandrosterone sulphate, androstenedione, 11-desoxycortisol, cortisol, testosterone and 11 beta-hydroxyandrostenedione by adenoma cells was either very low or undetectable. In the presence of ACTH, dibutyryl cyclic AMP or cholera toxin the secretion of dehydroepiandrosterone sulphate, androstenedione and 11-desoxycortisol increased markedly with time in culture up to 3 days, whereas the other steroids were undetected in the medium. A homogenate of adenoma tissue metabolized testosterone to androstenedione, but the conversion of androstenedione to testosterone was minimal. The findings of this study served to establish that virilization in this woman was due at least in part, to excess testosterone--and testosterone-derived 5 alpha-dihydrotestosterone--produced at extra-adrenal tissue sites almost exclusively through metabolism of tumour-secreted androstenedione.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Steroid secretory characteristics of a virilizing adrenal adenoma in a woman. 816 62


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