Biomedical subjects
C Scandellari
Publications and source records attributed to C Scandellari.
Plasma kallikrein activity in human diabetes mellitus.
It has recently been observed that administration of bradykinin to diabetic patients improves peripheral glucose utilization. To verify whether there is an alteration of the kallikrein-kinin system in human diabetes, plasma kallikrein activity was measured in 47 diabetic patients and in 20 control subjects. In diabetics plasma kallikrein activity was significantly higher than in controls: 1.04 +/- 0.04 U/ml (p less than 0.001). Although they do not refute the hypothesis that there is an alteration of the kallikrein-kinin system in diabetes mellitus, these findings do not support such a hypothesis either. Increased synthesis of plasma kallikrein activity may be due to increased synthesis of carbohydrate-protein compounds in diabetes mellitus.
Gonadal steroids and opioid control of gonadotropin secretion in man.
The aim of this study was to ascertain whether there was an interrelationship between gonadal steroids and endogenous opioid peptides. The effects of naloxone (20 mg, intravenously) and of a met-enkephalin analog (DAMME) (250 micrograms, intravenously) on gonadotropin secretion in three castrated men (18 to 23 years of age) and in five age-matched normal men were studied. Normal subjects were studied before and after treatment with a specific nonsteroidal estrogen receptor antagonist, clomiphene. Naloxone caused a significant increase in luteinizing hormone (LH) (P less than 0.05); in these subjects, clomiphene treatment significantly increased LH and follicle-stimulating hormone plasma levels but totally suppressed the naloxone-induced rise in LH. In castrated men, naloxone failed to increase plasma LH levels. However, DAMME significantly reduced plasma LH levels in normal, in castrated, and in clomiphene-treated normal subjects. The results demonstrate that in castrated subjects who lack gonadal steroids and in normal subjects with blocked estrogen receptors there is a reduced opioid inhibitory tone on gonadotropin secretion. The effect of DAMME on gonadotropin secretion, however, is not influenced by the gonadal steroid environment.
Studies on pituitary function in patients with B-cell adenoma.
Explore the source record for details and available documents.
Effects of naloxone on gonadotropin secretion in castrated young males before and after testosterone treatment.
Explore the source record for details and available documents.
75Se-methionine platelet survival studies: a proposal for a mathematical correction of the curve.
We studied platelet survival in 14 cardiac before heart valve replacement using 75Se-methionine 'cohort label'. The temporal variation of plasma and platelet activity was plotted by a continuous curve by means of a computerized interaction of the single points. Then we computed the plasmatic radioactivity fraction used daily for thrombopoiesis and made a subtraction of this aliquot from a experimental activity in the catabolic phase of the slope. Platelet life span obtained after this 'correction' is comparable with the values of random label using 51Cr.
[Not Available].
Explore the source record for details and available documents.
[Hypoglycemia. Pathogenetic considerations, classification and general diagnostic guidelines].
Explore the source record for details and available documents.
Effects of sodium DL-lactate on insulin secretion in anesthetized dogs.
The effect of sodium DL-lactate administration on insulin release in anesthetized dogs has been studied. Eleven mongrel dogs were infused with sodium DL-lactate for 20 min at the rate of 20 mg/kg . min. Lactate infusion produced simultaneous increases in blood glucose and plasma insulin levels in the pancreaticoduodenal vein. To determine whether lactate stimulated insulin secretion directly, sodium DL-lactate was rapidly injected into the pancreatic artery of six dogs; this pulse induced a significant increase in insulin release from pancreatic B-cells, even in the absence of a measurable change in blood glucose. Diazoxide, when infused in six dogs, blocked lactate-induced insulin secretion. These findings indicate that lactate, as do other circulating energy fuels, may play a role in the physiologic control of insulin secretion.
[Medical treatment of spontaneous hypoglycemic syndromes].
Explore the source record for details and available documents.
The effect of propranolol on hypoglycaemia. Observations in five insulinoma patients.
Five hypoglycaemic hyperinsulinaemic patients (three with proven benign insulinoma, one with proven metastasizing insulinoma, one with probable insulinoma not found at surgery) were treated with propranolol for a variable time ranging from two weeks to one year. Three patients showed favourable clinical results and a significant increase of the mean basal blood glucose level was found while two patients showed no improvement of the frequency of neuroglycopenic episodes and no significant increase of their mean blood glucose level. No patient showed a significant decrease in mean basal IRI concentration. A decrease of insulinaemic responses was observed during oral and intravenous glucose tolerance tests, a prolonged fast, and tolbutamide and glucagon tests performed in some patients. The results suggest that propranolol may induce in certain patients an improvement of basal clinical status through not understood effects (probably hepatic), which leave the peripheral concentrations of insulin unchanged, whereas inhibition of insulin secretion may represent the main way by which the improvement of metabolic situation during physiological or pharmacological stimulation may have been achieved.
Spontaneous fasting hypoglycemia: basal levels of plasma free fatty acids and glycerol, blood ketone bodies, serum cholesterol and plasma growth hormone.
Explore the source record for details and available documents.
Effect of chlorpromazine on blood glucose and plasma insulin in man.
In three groups of normal subjects and in one group of patients with latent diabetes mellitus a study has been made of the effects of chlorpromazine (CPZ) on blood glucose and plasma insulin. CPZ 75 mg/day for 7 days did not alter the plasma insulin response after oral glucose; nor did CPZ 50 mg/day for 7 days affect the glucose assimilation rate or insulin response to glucose injection. Infusion of CPZ 50 mg in 60 min slightly increased the basal blood glucose level but had no significant effect on basal plasma insulin. The insulin/glucose ratio after the end of the infusion was significantly higher than during the period of infusion of the drug. In latent diabetic patients CPZ infusion significantly diminished the insulin/glucose ratio during an intravenous glucose tolerance test. These results suggest that, whereas prolonged treatment with low doses of CPZ did not modify glucose tolerance and glucose-stimulated pancreatic response, higher acute doses of the drug may induce hyperglycaemia and can inhibit insulin secretion both in normal man and in patients with latent diabetes mellitus.
Hypoglycaemia induced by adrenal gland neoplasia (Anderson's syndrome) : report of a case.
A patient with hypoglycaemia associated with an adrenal neoplasia (Anderson's syndrome) is reported. Endocrinological investigation showed increased secretion of cortisol and catecholamines as well as an increased urinary steroid excretion along with profound inhibition of both basal and stimulated insulin secretion. During IVGTT, Conard's coefficient was reduced. The hyperglycemic response to glucagon injection was blunted, suggesting that liver glycogen stores were decreased or unavailable.
Plasma insulin response to glibornuride in thyrotoxicosis.
The glycemic and insulinemic response to i.v. glibornuride injection has been studied in a group of 8 euthyroid subjects and in a group of 9 thyrotoxic patients before and after reserpine treatment. In thyrotoxic patients sulfonylurea did not lower blood glucose more than in normal subjects. The plasma insulin response, however, was definitely higher than that of the controls in the first few minutes; after the 20th minute, however, levels of insulinemia were not appreciably different in the two groups. Insulin delivery rate was greater in hyperthyroid patients than in the controls. Administration of reserpine for a few days, did not modify either insulin response or blood glucose fall in thyrotoxic patients.
Medical treatment of endogenous organic hyperinsulinism.
There are several situations in which medical therapy of hyperinsulinism induced by islet cell tumors or hyperplasia is necessary and at present we have at our disposal several drugs which are capable of reducing endogenous hyperinsulinism. They are: -Streptozotocin, which represents today the most useful therapeutic agent for beta cell carcinoma therapy; -Diazoxide, which represents the drug of first choice for the treatment of most hypoglycemic syndromes caused by islet cell adenoma or hyperplasia; -Propranolol, Chlorpromazine, Diphenylhydantoin, which may be regarded as a useful alternative to diazoxide, although they are capable of giving rather inconstant results. These drugs may today effectively substitute for corticosteroids and glucagon in the medical treatment of almost every chronic hyperinsulinemic hypoglycemic syndrome, including malignant beta cell carcinoma.
In vivo studies on 5-hydroxytryptamine and insulin secretion in dogs and in man.
Explore the source record for details and available documents.
Effects of L-triiodothyronine on insulin secretion in man.
Explore the source record for details and available documents.