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R Toccafondi

Publications and source records attributed to R Toccafondi.

48 records · Page 3Linked to original sources
PubMedDate not supplied

Amino-oxidase and dermal connective tissue in scoliosis.

The amino-oxidase and collagen content of dermal tissue was evaluated in 10 patients with severe idiopathic scoliosis and in a control group of 7 patients with poliomyelitic scoliosis, that were to undergo surgical correction of their skeletal deformity. A greater dermal content of neutral salt souble collagen was found in the patients with idiopathic scoliosis, compared with the control group. Statistically the difference was highly significant. Mono-amino-oxidase activity, however, was found to be significantly decreased in dermal extracts obtained from patients affected by idiopathic scoliosis in comparison with controls. The involvement of mono-amino-oxidase in the crosslinking of collagen and the possible classification of idiopathic scoliosis as a systemic disease of connective tissue are discussed.

Adolescent↗
PubMedDate not supplied

Measurement of thyroid cell surface antibodies by radioassay using human cultured thyroid cells.

The present report describes a sensitive and quantitative binding radioassay for measurement of thyroid cell surface antibodies (TCSAb). Enzyme-dispersed thyroid cells from surgical specimens of human normal thyroid tissue were used after 7 days of culture. 125I-labelled Graves' IgG was shown to bind to cultured thyroid cells. The binding was time-and temperature-dependent and increased linearly with the number of thyroid cells. Evidence for specificity was provided by the lack of binding of radioiodinated Graves' IgG to human fibroblasts and by the negligible binding of 125I-labelled normal IgG to thyroid cells. A dose-dependent inhibition of binding of 125I-labelled Graves' igG to thyroid cells was produced by the addition of graded amounts of the unlabelled original Graves' IgG preparation, but not by normal IgG. Assays for TCSAb were performed on IgG preparations from patients with and without thyroid autoimmune disorders using the original Graves' IgG preparation as reference standard. Results were expressed in terms of arbitrary units/100 microgram IgG, 1 unit corresponding to the minimum amount of the standard IgG producing a significant inhibition of binding. Negative tests were found in most normal subjects (15/18) while low TCSAb levels (less than or equal to 1.8 U/100 microgram IgG) were detected in 3 cases. Increased TCSAb levels were found in the majority of the patients wit Graves' disease (14/21), in most of the patients with idiopathic myxedema (9/10) and in all of those with Hashimoto's thyroiditis (10/10).

Autoantibodies↗
PubMedDate not supplied

Neuropeptidergic control of cyclic AMP accumulation in human thyroid cell.

Somatostatin (SRIF), cholecystokinin (CCK), gastrin and substance P, as single agents, do not influence baseline cellular cAMP levels in human thyroid cultures. SRIF inhibits TSH-induced cAMP accumulation in human thyroid cell, while CCK, gastrin and substance P do not modify cAMP response to TSH. Vasoactive intestinal peptide (VIP) increases cellular cAMP levels in human thyroid cultures and its effect is additive to increases produced by norepinephrine (NE) and isoproterenol (ISO). Neither SRIF nor the other tested peptides influence adrenergic and VIP-ergic cAMP stimulation.

1-Methyl-3-isobutylxanthine↗
PubMedDate not supplied

Interaction of VIPergic and cholinergic receptors in human thyroid cell.

The thyroid tissue is innervated by cholinergic and VIPergic nerves. The present study investigated the possible interactions of cholinergic agents with VIP-induced cAMP accumulation and thyroid hormone release in vitro. Carbamylcholine (Cch), acting through the muscarinic receptor increases cellular cGMP content in cultured human thyroid cells incubated with a phosphodiesterase inhibitor. Cch (10 microM) inhibits cellular cAMP accumulation and thyroxine (T4) release induced by vasoactive intestinal peptide (VIP), with or without a phosphodiesterase inhibitor. Cch (10 microM) inhibits 8-bromo-cAMP-induced T4 release from human thyroid slices. 8-Bromo-cGMP inhibits VIP-induced T4 release from human thyroid slices, only in cells incubated without the phosphodiesterase inhibitor. The results indicate that interactions between VIPergic and cholinergic receptors may be of importance in human thyroid cell.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMedDate not supplied

Interaction between iodothyronines and thyrotropin receptor in human cultured thyroid cells.

In order to verify the existence of a "short-loop" negative feedback between iodothyronines and adenylate cyclase system of human thyroid, we have studied the effect of preincubation with iodothyronines, iodotyrosines, iodothyronine analogues and iodide on TSH-induced cAMP cellular accumulation in normal human thyroid cells in primary culture. Iodide did not produce an inhibitory effect on TSH-dependent adenylate cyclase system both in normal human thyroid plasma membranes and cultured cells. Iodothyronines at a 30-40 microM concentration did not inhibit the TSH-dependent adenylate cyclase activity of human thyroid plasma membranes; however at a 1 microM concentration they were able to inhibit the TSH-dependent cAMP accumulation by cultured cells. Preincubation with iodotyrosines and iodothyronine analogues failed to inhibit the TSH-responsive cAMP accumulation in human thyroid cultured cells.

Adenylyl Cyclases↗