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)

Monolayer cultures of human thyroid cells derived from thyroid adenoma were utilized for the assay of thyroid stimulating substances such as thyrotropin (TSH), cholera toxin and thyroid stimulating immunoglobulin (TSI) in patients with Graves' disease. Adenoma cells were treated with 0.1% collagenase or 2000 unit/ml dispase to thyrocytes. The cells were cultured in MEM containing 10% fetal calf serum under an atmosphere of 5% CO2 in air. Within 24 hours, the cells attached themselves to the plastic surface and formed a monolayer. Cyclic AMP responses to TSH, cholera toxin or Graves' IgG were tested in a medium (PBS) containing 0.5 mM IBMX. The cyclic AMP responses to TSH were generally maximal on the 3rd day of culture and declined thereafter. The response was dose-dependent, and 10 microU/ml of TSH produced a significant increase of cellular cyclic AMP. The response by 1 microU/ml of TSH was 28 approximately 57 fold above the basal. The response was also a function of the incubation period. The maximal response was attained after 1 h incubation. When the cultures were washed after exposure to TSH, the cellular cyclic AMP levels rapidly declined, suggesting that removal of receptor-bound TSH results in a prompt cessation of cyclic AMP production. The thyroid cells in monolayer also responded to cholera toxin. The response was dose-dependent, and cholera toxin as low as 1 ng/ml was able to increase cyclic AMP production. In contrast to the observations in TSH, the cyclic AMP responses induced by cholera were hardly affected by washing the cultures after exposure to cholera toxin. Treatment of the cells with cholera toxin for only 3 min resulted in a continuous stimulation of cyclic AMP production for more than 4 hours. Confirming recent observations by others, most of Graves' IgG stimulated cyclic AMP production in a dose-dependent manner, but some of them inhibited the response at high concentrations. IgG derived from normal subjects did not increase cellular cyclic AMP. The time course in the cyclic AMP responses induced by Graves' IgG was variable among the IgG preparations from different patients. In some patients, the maximal responses were attained after 4 hours of incubation. A significant difference was noted between TSH and Graves' IgG in the stimulation of cyclic AMP production after washing the cultures. When the cultures were treated with Graves' IgG for 30 min, washed and then incubated without Graves' IgG, cellular cyclic AMP levels remained at the levels which were almost equivalent to those observed in the continuous presence of the IgGs.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[The effects of TSH, cholera toxin and Graves' IgG on cAMP production in cultured human thyroid adenoma cells in monolayer]. 286 66

The leakiness of the cell membranes of colonic epithelial cells isolated by the collagenase/Dispase technique from normal or diseased colons was assessed in a 4 h 51Cr release assay. Cells from normal, adenoma bearing or cancer bearing colons showed 51Cr release of 8% or less in almost all of 46 cell populations tested. In contrast, cells from mucosa affected by ulcerative colitis [11.9 (4.3%) n = 23] or Crohn's disease [8.4 (2.7%) n = 18] released significantly more 51Cr than the non-inflamed groups. Values are expressed as mean (SD). Overall, release values were greater in ulcerative colitis than Crohn's disease (p less than 0.01). In Crohn's disease, cells obtained from histologically inflamed mucosa released significantly more 51Cr [9.7 (2.5%) n = 11] than those from non-inflamed mucosa [6.4 (1.5%) n = 7, p less than 0.02] whereas, in ulcerative colitis, abnormal release values were found in 8 of 13 cell populations isolated from mucosa showing no histological evidence of active disease. In five patients with distal ulcerative colitis, cells from mucosa not apparently involved demonstrated normal 51Cr release in four of five studies despite abnormal release from cells from involved mucosa suggesting that a diffuse abnormality of the colonic epithelial cell is not usually present. These data indicate that chronic mucosal inflammation per se is associated with abnormalities of the colonic epithelial cell but that, in ulcerative colitis, the abnormality remains in many patients with quiescent disease. Identification of the local factors responsible for such an abnormality may contribute to an understanding of the pathogenesis of ulcerative colitis.
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PMID:Ulcerative colitis--a disease characterised by the abnormal colonic epithelial cell? 337 20

Of the total urinary hydroxyproline in normal subjects and those with skeletal disorders, between 4 and 20% was nondialyzable. In some patients with Paget's disease of bone, hyperparathyroidism with osteitis fibrosa, hyperphosphatasia, and extensive fibrous dysplasia the total urinary hydroxyproline was sufficiently high to permit purification of this polypeptide hydroxyproline by gel filtration and ion exchange chromatography. The partially purified polypeptides had molecular weights between 4500 and 10,000 and amino acid compositions and physical properties resembling those of gelatin. The polypeptide fractions also contained neutral sugar and glucosamine. These fragments had been shown to be susceptible to cleavage by purified bacterial collagenase suggesting the presence of the sequence-Pro-X-Gly-Pro-Y-. After administration of proline-(14)C to patients with Paget's disease hydroxyproline-(14)C was excreted in the urine. The hydroxyproline-(14)C specific activity reached a peak in 2-4 hr and declined rapidly. The specific activity of the polypeptide (retentate) portion was severalfold greater than that of the raw urine and diffusate. When the labeled urines were subjected to gel filtration the hydroxyproline-(14)C fractions of highest molecular weight which were eluted first from the columns had the highest specific activities. Exposure of the hydroxyproline-(14)C-containing polypeptides to bacterial collagenase rendered them dialyzable. Four patients with hyperparathyroidism and osteitis fibrosa were studied before and after removal of a parathyroid adenoma, a period of transition from a predominance of bone collagen resorption to one of relatively increased bone collagen synthesis. The total urinary hydroxyproline fell rapidly after operation whereas the ratio of the polypeptide fraction to the total rose three- to fourfold. The results of these studies suggest that the urinary polypeptides represent fragments of collagen related to collagen synthesis. Changes in the ratio of these peptides to total hydroxyproline in the urine may serve as an index of new bone formation in patients with skeletal disorders.
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PMID:Urinary polypeptides related to collagen synthesis. 431 4

Subcellular fraction and collagenase-dispersed isolated adrenal fasciculata and glomerulosa cells from human and primate adrenal glands and cortisol-producing tumors have been utilized to study angiotensin II (Ang II) receptors and steroid biosynthesis. The receptor density of glomerulosa was threefold higher than that fasciculata. A benign cortisol-producing adenoma did not differ from normal fasciculata, but a malignant tumor had significantly lower affinity binding. Agonist and antagonist analogues of Ang II competed for binding sites commensurate with known biologic activity. The Kd Analogue binding also had corresponding changes in cortisol biosynthesis. The ED50 for aldosterone biosynthesis by glomerulosa cells was significantly lower at 55 pmol/L. Fewer receptors in human fasciculata as compared to glomerulosa and a less sensitive response to Ang II are consistent with previous in vitro observations in other species. These studies suggest that there may be a biologically relevant Ang II receptor of human and primate adrenal fasciculata that share many characteristics with the receptor of the glomerulosa.
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PMID:Angiotensin II receptors of human and primate adrenal fasciculata and glomerulosa: correlations of binding and steroidogenesis. 608 82

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

Several years ago the therapeutic possibilities for the treatment of inherited skin disorders were rather restricted; recently new possibilities have been developed and successfully applied. The author discusses the indications for a surgical procedure in basal cell nevus syndrome and the satisfying results revealed by dermabrasion in sebaceous adenoma of Pringle. The use of a low phenylalanine and tyrosine diet in case of palmoplantar keratosis with tyrosinemia is of theoretical as well as practical interest. However, a most striking therapeutic success is obtained by the treatment with drugs. The substitution of zinc in acrodermatitis enteropathica is very effective and not expensive! The positive effect of phenytoin in epidermolysis bullosa cicatricans is based on the partial inhibition of collagenase activity by this drug. Finally the author discusses the advantages of a treatment with retinoids in different hereditary keratinization disorders.
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PMID:[Therapeutic possibilities of hereditary diseases in dermatology]. 666 38

The activity of type I and IV collagenase was measured in thyroid tissue obtained from 6 non-diseased thyroids, 4 patients with Graves' diseases, 5 with follicular adenoma, 6 with papillary carcinoma and 4 with follicular carcinomas. The relationship between these enzyme activities and invasion or metastasis of the original tumors was studied. The activity of type I collagenase in papillary carcinomas and follicular carcinomas was higher than in non-diseased thyroids, Graves' disease and follicular adenoma. Carcinoma tissue with invasion beyond the capsule in particular had higher type I collagenase activity. Type IV collagenase activity in carcinoma with lymph node metastasis was higher than in non-diseased thyroids, Graves' disease and follicular adenoma, and especially higher than carcinoma without lymph node metastasis. These findings suggest that increased type I collagenase activity plays an important role in local invasion in thyroid carcinoma, and that increased type IV collagenase activity plays an important role in lymph node metastasis.
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PMID:[Study of type I and IV collagenase activity in human thyroid diseases]. 762 46

Ammonium perfluorooctanoate (C8) produced a dose-dependent increase in Leydig cell adenomas in Crl:CD BR (CD) rats fed 0, 30, or 300 ppm for 2 years. Administration of C8 to adult male CD rats, by gavage for 14 days, produced decreased serum and testicular interstitial fluid testosterone levels and increased serum estradiol levels. The C8-mediated decrease in the serum testosterone levels appeared to be due to a lesion at the level of the testis. These endocrine changes may play a role in the C8 induction of Leydig cell tumors. In the present work, C8 was examined for its ability to (1) directly affect Leydig cells in vitro using isolated Leydig cells from untreated rats and ex vivo using Leydig cells isolated from C8-treated rats, (2) affect testicular interstitial fluid hormone levels, and (3) induce aromatase activity. These studies were conducted to investigate the hypothesis that C8 produces an increase in estradiol by inducing cytochrome P450 XIX (aromatase), which converts testosterone to estradiol, and that the elevated estradiol levels ultimately produce Leydig cell hyperplasia and adenoma formation by acting as a mitogen or enhancing growth factor secretion. In the in vivo and ex vivo studies, adult male CD rats were gavaged with either 0 or 25 mg/kg/day C8 for 14 days. In addition to the ad libitum control, a second control group was pair-fed to the 25 mg/kg/day C8 group. In the in vitro and ex vivo studies, Leydig cells were isolated from testes of adult males by collagenase digestion followed by enrichment over Percoll gradients. A dose-dependent decrease in testosterone levels was observed in hCG-stimulated Leydig cells treated in vitro with C8 for 5 hr (IC50 approximately 200 microM). In contrast, ex vivo studies demonstrated an increase in testosterone production in hCG-stimulated Leydig cells from C8-treated rats when compared to Leydig cells isolated from either the ad libitum or pair-fed control rats. The in vitro data demonstrate that C8 directly inhibits testosterone release from Leydig cells, while the ex vivo data demonstrate that this inhibition is reversible.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of ammonium perfluorooctanoate on Leydig cell function: in vitro, in vivo, and ex vivo studies. 767 54

Tumor invasion and metastasis are complex phenomena believed to be facilitated by the disruption of collagen and elastin fibers in the extracellular matrix. Interstitial collagenase gene expression was studied in colonic adenocarcinoma and adenoma using in situ hybridization. The data indicated that three cell types within the tumor stroma expressed collagenase transcripts; they were eosinophils, fibroblasts, and vascular endothelium. In all 12 adenocarcinomas, a high to moderate level of expression was seen in 1 to 5% of eosinophils and in occasional fibroblasts, whereas these cell types in non-neoplastic mucosa adjacent to tumor showed no detectable expression. Two adenocarcinomas showed expression in hyperplastic endothelium in vascularized granulation tissue. Two out of three adenomas showed expression in eosinophils and fibroblasts at a reduced level. Tissue inhibitor of metalloproteinase-1 gene expression was, however, negligible in all tissue examined. These results suggest that interstitial collagenase gene activation in the tumor stroma, especially eosinophils, may have an important role in tumor invasion and metastasis.
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PMID:Interstitial collagenase gene expression in colonic neoplasia. 836 69

Epithelial properties of thyrocytes are difficult to maintain in conventional cell culture systems. We used bicameral chambers (Transwell) in attempts to establish a functional epithelium of thyrocytes of human origin. Thyroid follicle segments were isolated by collagenase digestion of paradenomatous tissue obtained at surgery for follicular adenoma and of tissue from glands with Graves' disease. After careful separation from connective tissue and single cells by centrifugation, the follicles were plated at high density on the collagen-coated filter of the chambers and cultured in Eagle's essential medium (EMEM) containing 10% fetal calf serum (FCS) or Coon's modified Hams medium enriched with five or six factors (5H, 6H); the latter media contained 5% FCS without (5H) or with (6H) thyrotropin (TSH). The follicles were converted into a confluent cell layer, which had similar DNA content irrespective of type of medium, after 4-6 days. Cells grown in EMEM or 5H established a transepithelial electrical resistance (R) of 200-500 omega.cm2 and was impermeable to [3H]inulin, indicating the formation of epithelial junctions. Addition of 6H to confluent cells initially cultured in EMEM or 5H caused a further increase of R, maximally to 1500 omega.cm2, along with a rise of the transepithelial potential difference; 6H promoted the monolayer formation of cells, increased the number of apical microvilli and reinforced the junctional distribution of actin, cadherin and ZO-1; 6H also enhanced the polarized secretion of [3H]leucine-labeled thyroglobulin into the apical medium. Cells from Graves' thyroid tissue established an epithelium on the filter with similar characteristics to that of normal thyrocytes; some platings contained in addition large numbers of HLA-DR positive cells with a dendritic shape. HLA-DR expression was generally absent in EMEM-or 5H-grown thyrocytes, but appeared in limited areas of the cell layer after 6H and was expressed by all epithelial cells after interferon-gamma stimulation for 48 h. We conclude that human thyrocytes form a tight and polarized epithelium when cultured on permeable filters. The polarized structure and function of the cells are positively regulated by TSH. The culture system may be useful in studies addressing the role of the epithelial phenotype (cell polarity and tight barrier) in normal thyroid function as well as in pathological processes in the thyroid, such as autoimmunity, cell transformation and tumor progression.
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PMID:Primary culture of human thyrocytes in Transwell bicameral chamber: thyrotropin promotes polarization and epithelial barrier function. 892 31


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