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C Brossa

Publications and source records attributed to C Brossa.

9 recordsLinked to original sources
PubMed1987

Initial treatment of thyrotoxic Graves' disease with methimazole: a randomized trial comparing different dosages.

We evaluated the efficacy of different doses of methimazole (MMI) as the initial therapy for Graves' disease. Fourteen patients were treated with 15 mg/die of the drug (group A) and 14 with 30 mg/die (group B). Blood samples for T3, T4, FT3 and FT4 were obtained before beginning therapy, every 48 h during the first 12 days and on the 45th day of treatment. All these hormonal parameters fell significantly from the 2nd day of therapy in both groups. All the patients, except for one in group B, had normal or subnormal levels of thyroidal hormones on the 45th day of treatment. The comparison between the two groups of regression coefficients over the first 12 days showed no significant differences. The absolute decrease of each examined parameter on day 12 was positively correlated with the relevant pretreatment value. These results demonstrate that doses of MMI (15 mg/die) much lower than those commonly recommended are able to rapidly control thyroidal overproduction as effectively as 30 mg/die.

Adult↗
PubMed1987

Use of the thyroid 99Tcm scintiscan with lead-shield on the hot nodule in the diagnosis of autonomous adenoma.

Eighteen patients bearing a hot nodule, imaged by basal 99Tcm scintiscan and toxic in eight of them, were studied. All patients underwent 99Tcm thyroid scintiscan in basal conditions and after placing a lead-shield on the hot thyroid nodule, without other radioisotope administration. In eight cases the thyroid scintiscan after lead-shield overlapping the hot nodule, was compared to a second 99Tcm thyroid scintiscan after thyrotrophic hormone stimulation, TSH. This technique of nodule shielding was able to show the extranodular tissue in 15 patients; in the remaining three cases neither this approach nor the scintiscan after exogenous TSH were able to demonstrate any remainder thyroid parenchyma. Thus, this scintigraphic method can be considered excellent in the diagnosis of autonomous adenoma: it needs, in fact, a single radioisotope administration and does not present the adverse effects frequently induced by exogenous TSH.

Adenoma↗
PubMed1983

Changes in insulin binding activity during myeloid differentiation.

Insulin binding activity and its changes in relation to terminal differentiation were studied in the HL60 human promyelocytic cell line, and in myeloid cells from both normal bone marrow and chronic myeloid leukemia (CML) patients. After treatment with dimethylsulfoxide, the HL60 line began to differentiate into more mature myeloid cells. Treated and untreated HL60 cells were found to possess specific insulin receptors with characteristics similar to those of monocytes and granulocytes. Dimethylsulfoxide induced a progressive decrease in insulin binding, parallel to the increase in the proportion of differentiated cells. Myeloid cells from CML patients were used to study insulin binding characteristics during spontaneous differentiation. They were separated on Ficoll Hypaque into a light fraction, containing mostly undifferentiated cells, and a dense fraction, containing mostly granulocytes, with similar specific insulin receptor characteristics. Insulin binding capacity, however, was twice as high in the light fraction. To compare binding activity during normal and leukemic myeloid differentiation, cells from normal bone marrow and CML peripheral blood were fractioned by BSA density gradient into enriched fractions of one predominant cell type. Insulin binding decreased in the course of both differentiations. These findings indicate that leukemic immature myeloid cells possess a high number of specific insulin receptors, and that insulin binding decreases during both spontaneous and chemically induced terminal differentiation.

Bone Marrow↗
PubMed1981

Kinetic analysis of the response of plasma glucose, insulin, and C-peptide to glucagon injection in normal and diabetic subjects.

A compartmental model formed by plasma glucose, proinsulin, insulin, and C-peptide was proposed to allow a quantitative evaluation of the interrelationship among the different components of the system and to obtain a better discrimination between normal and pathologic subjects. In 11 control subjects, in 6 mild diabetics, and in 9 severe diabetics (insulin-dependent), the kinetics of plasma glucose, insulin, and C-peptide after an i.v. injection of glucagon (sampling for about 120 min) were fitted to the model which was solved with digital computing techniques. Since biphasic plasma insulin and C-peptide kinetics were demonstrated in many normals and mild diabetics, the effect of glucagon in the model was represented by a differential plus a proportional effect. The model (formed by 6 compartments and 14 transfer constants) takes into account the fact that insulin and C-peptide derive monomolecularly from proinsulin and that liver inactivates insulin. The values of the parameters obtained were submitted to stepwise discriminant analysis in order to obtain their relative importance in discriminating among the three groups of subjects. With respect to normal subjects, we found in diabetics an increased inflow of glucose into plasma; a decreased effect of glucagon in promoting the proinsulin response; a decreased effect of glucose in promoting the proinsulin response; a decreased glucose utilization; a lower coupling effect of insulin on glucose; and a higher disappearance rate of C-peptide. We observed a lower formation of insulin and C-peptide from proinsulin in severe diabetics.

Adult↗
PubMed1980

[Insulin receptors in the HL60 human promyelocytic leukemic cells line].

The insulin binding characteristics of human promyelocitic HL60 cell line was studied by the use pf I(125) insulin. The binding activity was found to increase linearily both with the number of cells and with the incubation time. The competition curve with increasing concentration of unlabeled insulin demonstrated of specific receptors. The number of receptors was estimated to be 6.36 . 10(6) per cell.

Cell Line↗
PubMed1980

[Decrease of insulin binding to human acute leukemic cells during chemically induced differentiation].

The specific insulin binding activity of human promyelocitic HL 60 cell line during the myeloid and macrophagic differentiation induced by chemical compounds was investigated. Dimethyl sulfoxide (DMSO) and retinoic acid myeloid induced differentiation in HHL 60 cells was accompanied by a marked decrease of insulin receptors. In K 562 cell line, where DMS O has no effect on differentiation, the number of insulin receptors was only slightly affected. 12-0-tetradodecanoil phorbol 13-acetate (TPA) induced macrophagic differentiation of HL 60 cell line was also accompanied by a decrease of insulin binding activity. Our results support the hypothesis that during the process of terminal differentiation a decrease of insulin receptors occurs.

Cell Differentiation↗
PubMed1980

[Serum levels and kinetics of digoxin in patients with hyperthyroidism (author's transl)].

The mechanism of reduced sensitivity to digitalis in patients with hyperthyroidism has been attributed to a change of intrinsic myocardial function and/or to altered pharmacokinetics of cardiac glycosides. Digoxin kinetics have been studied in hyperthyroid and 8 euthyroid patients after a single oral and i.v. dose at steady-state. Plasma and urinary digoxin concentrations were determined by radioimmunoassay. A significantly mean lower serum digoxin concentration was found in hyperthyroid patients, both after a single oral drug administration and at the steady-stage. A decreased digoxin absorption could not account for this finding, since both the percentage of gastrointestinal uptake of the drug and maximal serum concentration did not differ in hyperthyroid patients as compared to controls. Hyperthyroid subjects showed, on the contrary, an expended distribution volume and a significantly higher excretion, as documented by a lower drug half-life, by the increase of the elimination constant and urinary digoxin output.

Adult↗