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U Modigliani

Publications and source records attributed to U Modigliani.

13 recordsLinked to original sources
PubMed1990

Insulin-like growth factor-I receptors in nonfunctioning thyroid nodules.

We have recently demonstrated the production of insulin-like growth factor-I (IGF-I) as well as the presence of type I IGF receptors in human thyroid cells in primary culture. The role of IGF-I in the control of thyroid cell growth has been well established. In order to investigate the involvement of IGF-I in abnormal thyroid growth, the density of IGF-I receptors in solitary, cold, micro- and macro-follicular thyroid adenomas, and in extranodular histological normal tissue was studied. Forty-three euthyroid patients with isolated cold nodules were selected for the study. In 30 patients the presence of IGF-I receptors was evaluated by using quantitative immunohistochemistry; in 10 patients by using radioligand binding studies, and in 3 patients by using affinity labeling. Cross-linking and binding studies clearly demonstrated the presence of a homogeneous class of binding sites for type I IGF receptors. Furthermore, radioligand studies did not show any significant differences in receptor density between the 2 types of thyroidal tissues. Conversely, the computerized analysis of 900 fields of nodular and normal thyroid tissues immunostained with the monoclonal antibody alpha-IR3, strongly indicated that higher concentrations of IGF-I receptors were present in the epithelial cells of non-functioning thyroid nodules than in the adjacent extranodular thyroid tissues. These studies strongly suggest that the same type I IGF receptor is present in thyroid follicular adenomas as in histological normal thyroid tissue removed from the same patient. The higher concentration of IGF-I receptors as documented by immunostaining in the adenomas suggests that IGF-I may contribute to the abnormal growth of the neoplasms.

Adenoma↗
PubMed1986

Transient lack of response to TSH of human cultured thyroid cells obtained from hyperfunctioning tissue.

TSH-induced cAMP accumulation in cells obtained from normal and pathological thyroid tissue was studied during the first 12 days of primary culture. In normal thyroid tissue cultures (N = 7), the response of cAMP to TSH was present from the second day of culture and reached its maximum after 8 days. A similar behaviour was observed in cultures obtained from euthyroid sporadic goitres (N = 8), even if the rate of response was slightly lower than that of normal tissue. Similarly, cultured cells from euthyroid 'autonomous' nodules (N = 8) appeared to be responsive to TSH during the period of study, but the rate of response was also lower than in the controls. On the contrary, in cultures obtained from toxic adenomas (N = 5) and from diffuse toxic goitres (N = 5) the response to TSH was absent during the first 4 days of culture. The cells became sensitive to TSH from 6 and 6 day onwards, with the rate of response increasing progressively and reaching its maximum on day 12. Finally, in cultured cells obtained from different areas of multinodular toxic goitres (N = 4), the response to TSH was similar to that of euthyroid goitres in cells prepared from 'cold' areas, and to that of toxic adenomas in cells obtained from 'hot' areas. The present data demonstrate the existence of an inhibitory action of unknown factors, possibly iodothyronines or thyroglobulin, on the TSH effect in short-term cultures obtained from thyrotoxic tissues. A normal TSH responsiveness can be restored when the culture is prolonged.

Adenoma↗
PubMed1981

Thyroxine and triiodothyronine levels in thyroid vein blood and in thyroid tissue of patients with autonomous adenomas.

Thyroxine (T4) and triiodothyronine (T3) concentrations were measured in peripheral and thyroid vein blood and in nodular and extranodular thyroid tissue from twenty-four patients with autonomous thyroid nodules (AFTN); fifteen of these patients showed clinical signs of hyperthyroidism and nine were euthyroid. Thirteen patients with solitary non-functioning thyroid adenomas who were clinically euthyroid, served as controls; samples of thyroid vein blood and normal thyroid tissue being obtained from the contralateral lobe. T4 (189.4 +/- 27.2 nmol/l) and T3 (7.05 +/- 2.03 nmol/l) concentrations were significantly higher in the thyroid vein blood of patients with AFTN compared with controls (T4 = 119 +/- 9.1 nmol/l, P less than 0.05; T3 = 2.3 +/- 0.21 nmol/l, P less than 0.01) whereas peripheral levels in the two groups were similar. The T3 concentrations (10.56 +/- 4.12 nmol/g wet tissue) in autonomously-functioning thyroid nodular tissue were significantly higher than those of extranodular (1.9 +/- 0.62 nmol/g wet tissue, P less than 0.01) and normal thyroid tissue (2.63 +/- 0.43 nmol/g wet tissue, P less than 0.05). The T4 levels were not different in the tissues examined. The concentrations of T4 and T3 in thyroid vein blood did not show any significant correlation with the hormone levels in thyroid tissue.

Adenoma↗
PubMedDate not supplied

Localization of transferrin receptors (TFRs) in human non functioning thyroid nodules and in extranodular thyroid tissue.

In this research the TFR localization in non functioning human thyroid nodules and in the extranodular thyroid tissue, using an immunohistochemical technique, has been studied. For this study a monoclonal antibody (B3/25) against TFR and the peroxidase technique have been utilized. Moreover a morphometric comparative analysis was carried out based on the following parameters: 1) mean immunoreactive area for microscopic field, 2) mean value of immunoreactive follicular perimeter, 3) integrated optical density, 4) % of immunoreactive area on total examined area in nodular and extranodular tissue. The immunoreactivity was detected in some follicular cells in a number of follicles randomly distributed in the extra nodular tissue. As concern the non functioning thyroid nodules, the positivity was localized in the generality of the follicles both in the flattened epithelial cells of the larger follicles and in the cuboidal cells of the smaller ones. The morphometric parameters confirm a statistically significant difference of immunoreactivity between extranodular and nodular tissue. These results suggest that TF might play a role in the cellular proliferation of thyroid gland.

Cell Division↗