Search PubMedSearch

Biomedical subjects

G Piscitelli

Publications and source records attributed to G Piscitelli.

18 recordsLinked to original sources

A comparison of cabergoline and bromocriptine in the treatment of hyperprolactinemic amenorrhea. Cabergoline Comparative Study Group.

BACKGROUND: Cabergoline is a long-acting dopamine-agonist drug that suppresses prolactin secretion and restores gonadal function in women with hyperprolactinemic amenorrhea. We designed a study to compare its safety and efficacy with those of bromocriptine, which has been the standard therapy. METHODS: A total of 459 women with hyperprolactinemic amenorrhea were treated with either cabergoline (0.5 to 1.0 mg twice weekly) or bromocriptine (2.5 to 5.0 mg twice daily), administered in a double-blind fashion for 8 weeks and subsequently in an open fashion for 16 weeks, during which adjustments in the dose were made according to the response. Of the 459 women, 279 had microprolactinomas, 3 had macroprolactinomas, 1 had a craniopharyngioma, 167 had idiopathic hyperprolactinemia, and the remainder had an empty sella. Clinical and biochemical status was assessed at 2-week intervals for 8 weeks and monthly thereafter for a total of 6 months, with an additional assessment at 14 weeks. RESULTS: Stable normoprolactinemia was achieved in 186 of the 223 women treated with cabergoline (83 percent) and 138 of the 236 women treated with bromocriptine (59 percent, P < 0.001). Seventy-two percent of the women treated with cabergoline and 52 percent of those treated with bromocriptine had ovulatory cycles or became pregnant during treatment (P < 0.001). Amenorrhea persisted in 7 percent of the cabergoline-treated women and 16 percent of the bromocriptine-treated women. Adverse effects were recorded in 68 percent of the women taking cabergoline and 78 percent of those taking bromocriptine (P = 0.03); 3 percent discontinued taking cabergoline, and 12 percent stopped taking bromocriptine (P < 0.001) because of drug intolerance. Gastrointestinal symptoms were significantly less frequent, less severe, and shorter-lived in the women treated with cabergoline. CONCLUSIONS: Cabergoline is more effective and better tolerated than bromocriptine in women with hyperprolactinemic amenorrhea.

Adolescent

Pharmacodynamics and relative bioavailability of cabergoline tablets vs solution in healthy volunteers.

The effect of formulation on the urinary pharmacokinetics, pharmacodynamics, and relative bioavailability of cabergoline was investigated. Twelve healthy female volunteers, aged 23-35 years, were treated, according to an open, randomized, crossover design, with cabergoline (1-mg single oral dose) both as tablets and as a solution. The two administrations were separated by a 4-week wash-out period. Cabergoline and prolactin were measured in urine and plasma, respectively, by specific radioimmunoassays. Blood samples were collected before and up to 30 days after dosing. Urine was collected before and up to 8 days after dosing. Cabergoline elimination half-lives calculated from urinary data were 68 and 63 h after administration of the tablets and the solution, respectively. Urinary excretion of unchanged cabergoline accounted, on average, for 1.92% (range, 0.14-3.26) and 1.80% (range, 0.67-3.09) of the dose after administration of the tablets and the aqueous solution, respectively. Relative bioavailability of tablets vs solution was 99% (geometric mean with the 90% confidence intervals of 68-144%). Prolactin levels in 10 out of 12 subjects fell below the detection limit of the assay (1.5 micrograms/L) after both treatments. The mean maximum prolactin decrease (ca. 70%) was achieved by 2 or 3 h after dosing; the effect persisted up to 9 days, being completely exhausted 23-28 days after dosing. The analysis of variance performed on the pharmacodynamic effects of the two cabergoline formulations indicated that the percent decreases of plasma prolactin levels were not significantly different for tablets and solution. These results indicate that the pharmacodynamics and relative bioavailability of cabergoline are not influenced by formulation, as tablets or solution.

Adult

The efficacy and tolerability of long-term cabergoline therapy in hyperprolactinaemic disorders: an open, uncontrolled, multicentre study. European Multicentre Cabergoline Study Group.

OBJECTIVE: We assessed the efficacy and safety of the new, long-acting dopamine agonist drug cabergoline during long-term therapy of hyperprolactinaemia. DESIGN: Open, prospective, multicentre study. PATIENTS: One hundred and sixty-two females with either a microprolactinoma (n = 100), idiopathic hyperprolactinaemia (n = 54), empty sella syndrome (n = 7) or residual hyperprolactinaemia after surgery for a macroprolactinoma (n = 1). All had previously been treated with cabergoline or placebo for 4 weeks as part of a dose-finding study. MEASUREMENTS: Menstrual pattern, adverse symptoms, blood pressure and pulse, serum PRL, blood count, liver and renal function were assessed after one month and subsequently at two-monthly intervals. RESULTS: Treatment was started at doses of 0.25 mg (n = 3), 0.5 mg (n = 8), 1 mg (n = 150) or 2 mg (n = 1) per week, given either as a single weekly dose (n = 8) or divided into twice-weekly doses (n = 154), and was continued for at least 49 weeks in 123 patients. Final treatment doses ranged from 0.25 mg fortnightly to 2 mg twice weekly: most patients finished the study taking 0.5 mg once (n = 31) or twice (n = 77) weekly. Stable normalization of PRL levels was achieved in 138 subjects (85%), in 129 of whom the effective dose was < 1 mg per week. In the subset of 114 patients completing 49 weeks of therapy and having dose adjustments according to the protocol, the biochemical success rate was 92%. Fifty-nine of the 65 previously amenorrhoeic women (91%) and 44 of the 49 (90%) who were previously oligomenorrhoeic resumed regular menses and/or became pregnant during the study. Adverse events were reported in 64 patients (39.5%). In 84% of cases with adverse events, the symptoms were of mild or moderate severity and most occurred during the first few weeks of therapy; five patients (3%) discontinued treatment because of poor tolerance. The most frequent symptoms were dizziness (13% of patients), headache (13%), nausea (10%) and weakness and/or fatigue (10%). Of 27 patients who had previously been poorly tolerant of other dopamine agonists, 17 (63%) did not experience any side-effects and only one was intolerant of cabergoline. No adverse haematological or biochemical effects were detected except for a slight downward trend in haemoglobin which may have been related to the resumption of regular menses in previously amenorrhoeic or oligomenorrhoeic women. A mild hypotensive effect was observed, mean systolic and diastolic blood pressures falling by 5 and 4 mmHg respectively during treatment. CONCLUSIONS: The results provide evidence for the long-term effectiveness and safety of cabergoline in the treatment of hyperprolactinaemia. Its ability to normalize PRL and restore gonadal function compares favourably with reported data on reference compounds while its tolerability profile and simple administration schedule offer potential advantages in terms of patient acceptability.

Adult

Dose-dependent suppression of serum prolactin by cabergoline in hyperprolactinaemia: a placebo controlled, double blind, multicentre study. European Multicentre Cabergoline Dose-finding Study Group.

OBJECTIVE: Dopamine agonists have a well established place in the treatment of hyperprolactinaemic disorders but their use is associated with a high incidence of adverse effects. We have investigated the biochemical efficacy and side-effect profile of a range of doses of the novel, long-acting dopamine agonist, cabergoline, in suppressing prolactin (PRL) in hyperprolactinaemic women. DESIGN: Multicentre, prospective, randomized, placebo controlled and double blind. PATIENTS: One hundred and eighty-eight women with hyperprolactinaemia secondary to microprolactinoma (n = 113), idiopathic disease (n = 67), empty sella syndrome (n = 7) or following failed surgery for a macroprolactinoma (n = 1). MEASUREMENTS: Weekly assessment of adverse symptoms, blood pressure and pulse, serum PRL, blood count, liver and renal function. RESULTS: Patients received either placebo (n = 20) or cabergoline 0.125 (n = 43), 0.5 (n = 42), 0.75 (n = 42) or 1.0 mg (n = 41) twice weekly for 4 weeks. The five treatment groups were comparable in age (mean 31.8, range 16-46 years), diagnosis, previous therapy, and pretreatment serum PRL. PRL was suppressed to below half the pretreatment level in 5, 60, 90, 95 and 98% and normalized in 0, 30, 74, 74 and 95% of patients taking placebo or cabergoline 0.125, 0.5, 0.75 or 1.0 mg twice weekly respectively (Armitage's test, chi 2 = 39.3, P < 0.01). Cabergoline therapy (all doses) restored menses in 82% of the amenorrhoeic women not previously treated with dopamine agonists. Adverse events were recorded in 45% of patients in the placebo group and in 44, 50, 50 and 58% of those taking 0.125, 0.5, 0.75 and 1.0 mg cabergoline twice weekly (Armitage's test, P > 0.05). Over 95% of reported symptoms were relatively trivial, most frequently transient nausea, headache, dizziness, fatigue and constipation. More severe adverse events, interfering significantly with the patients' lifestyle, occurred in 13 (7.7%) patients taking cabergoline; treatment withdrawal was necessary in only one case. No adverse effects were detected on blood pressure or haematological or biochemical parameters. CONCLUSIONS: We have shown a linear dose-response relationship for cabergoline in the treatment of hyperprolactinaemia in the range 0.125-1.0 mg twice weekly, with normalization of PRL in up to 95% of cases and acceptable tolerability throughout the dose range.

Adolescent

Treatment of hyperthyroidism due to inappropriate secretion of thyrotropin with the somatostatin analog SMS 201-995.

The management of hyperthyroidism due to inappropriate secretion of TSH (IST) includes agents that selectively suppress TSH hypersecretion both in patients with TSH-secreting tumor [neoplastic IST (nIST)] in whom pituitary surgery was unsuccessful and in those with selective pituitary resistance to thyroid hormone action [nonneoplastic IST (nnIST)]. Among such agents, somatostatin administration has proven to be effective in blocking TSH hypersecretion, but its short plasma half-life prevented its use in long term therapeutic trials. The recent availability of a potent and long-acting analog of somatostatin (SMS 201-995, Sandostatin) prompted us to study its effects on serum TSH, alpha-subunit, and free thyroid hormone (FT4 and FT3) concentrations in five patients with nIST and three patients with nnIST. During short term SMS 201-995 administration (100 micrograms, sc, three times daily for 5 days) both serum TSH and alpha-subunit levels decreased in all patients with nIST (mean decrements, -86% and -85%, respectively), with concomitant normalization of serum FT4 and FT3 concentrations. In the three patients with nnIST, this treatment lowered serum TSH levels less well (mean decrement, -47%), although serum FT4 and FT3 levels normalized in one patient. Chronic SMS 201-995 (100 micrograms, sc, every 12 h for 1-7 months) treatment in four hyperthyroid patients (two with nIST and two with nnIST) resulted in a steady euthyroid state in both patients with nIST, with restoration of normal visual fields in one patient. In contrast, in both patients with nnIST, escape occurred after 2 weeks of therapy. We conclude that SMS 201-995 administration is effective treatment for patients with nIST, able to suppress TSH hypersecretion from the adenomatous thyrotrophs and, consequently, to restore clinical and biochemical euthyroidism in such patients. On the contrary, the inhibitory effects of SMS 201-995 on TSH secretion in patients with nnIST are weaker and transient.

Adult

Treatment of inappropriate secretion of thyrotropin with somatostatin analog SMS 201-995.

Inappropriate thyrotropin secretion (IST) may originate from either neoplastic disease (nIST) or non-neoplastic resistance to thyroid hormone (nnIST). An inhibitory effect of somatostatin on TSH secretion has been documented. In an attempt to elucidate the possible therapeutic effect of this peptide on nIST and nnIST, a study was conducted in 7 such patients. Sandostatin (SMS 201-995) was administered in daily doses of 100 micrograms for several days to 1 month. Four patients with nIST responded with a fall in circulating TSH as well as alpha-subunit with concomitant normalization of free thyroxine and clear symptomatic improvement. In the 3 nnIST patients this effect was considerably less apparent and a partial TSH escape was observed on long-term treatment in 2 cases. The importance of somatostatin and its analogs in the management of thyroid malignancy is stressed.

Antineoplastic Agents

Iopamidol 150 in intra-arterial digital angiography of the peripheral vasculature: a comparative study.

The results of a comparative double-blind clinical trial involving peripheral intra-arterial DSA performed with low iodine iopamidol concentrations (150 and 200 mg. I/ml.) are reported. Forty-six patients were examined for vital signs, local (heat and pain sensations) and systemic reactions and monitored throughout the procedure. No untoward effect was observed apart from mild local reactions, which on the other hand did not produce any movement artifacts. Image quality was good to optimal in 98% of the cases. In no case were higher concentrations of contrast medium (cm) needed. No significant differences between the two concentrations of cm used were observed with respect to either contrast ability or tolerability.

Angiography

Inappropriate secretion of thyrotropin by the pituitary.

Inappropriate secretion of thyrotropin (IST) is characterized by elevated serum free thyroid hormone and unsuppressed thyrotropin (TSH) levels, and results from either a TSH-secreting pituitary tumor (nIST) or a selective resistance to thyroid hormone action (nnIST). Although in most patients TSH levels are definitely high, in a quarter of the cases they are within the 'normal range'. In some of these cases, TSH had an elevated biologic activity and an apparent molecular weight smaller than in normals. The current availability of ultrasensitive TSH immunoradiometric assay, able to distinguish suppressed from unsuppressed TSH levels enables the recognition of the disease. The distinction between nnIST and nIST rests on clinical, neuroradiological, and biochemical criteria, the most useful of which are the alpha-subunit:TSH molar ratio (increased in nIST), and the evaluation of the TSH responses to thyrotropin-releasing hormone and high doses of 3,5,3'-triiodothyronine, both qualitatively normal in nnIST, while absent in nIST. The therapy of choice for patients with nIST is pituitary surgery, followed by irradiation in case of surgical failure. Chronic administration of bromocriptine is effective in a minority of cases. The long-acting somatostatin analogue SMS 201-995 has given promising results in 2 patients. In nnIST, bromocriptine is frequently uneffective, while small doses of 3,5,3'-triiodothyronine or 3,5,3'-triiodothyroacetic acid, a thyroid hormone derivative with a strong inhibitory effect on TSH secretion but poor thyromimetic activity on peripheral tissues, are effective in controlling TSH hypersecretion.

Humans

Evidence for an inhibition of thyroid hormone effects during chronic treatment with amiodarone.

The effects of chronic amiodarone treatment on several thyroid and cardiac function parameters were studied in 50 euthyroid patients with refractory ventricular arrhythmias, divided in responders and nonresponders according to their sensitivity to the antiarrhythmic action of the drug. No differences in the severity of cardiac disease and blood amiodarone concentrations were found in the two groups. Amiodarone induced a significant inhibition of peripheral T4 monodeiodination, more pronounced in responders compared to nonresponders. On the contrary, only in responsive patients, elevated basal and TRH-stimulated TSH levels were observed (despite serum T3 levels were not different from those in nonresponders) and the indirect indices of cardiac performance, particularly the systolic time intervals, fell in a range usually observed in the hypothyroid states. These findings suggest that amiodarone, besides the well-known inhibition of T4 to T3 conversion, also induces a partial resistance to the thyroid hormones, which is probably involved in the therapeutical effectiveness of the drug.

Adolescent

Endocrine, biochemical, and morphological studies of a pituitary adenoma secreting growth hormone, thyrotropin (TSH), and alpha-subunit: evidence for secretion of TSH with increased bioactivity.

A 40-yr-old man who had acromegaly and hyperthyroidism due to a GH/TSH-secreting pituitary adenoma is described. Serum free T4 was 2.8 ng/dl, free T3 was 1.1 ng/dl, and TSH was 1.2-1.5 microU/ml; the latter was measured in an immunoradiometric assay with a sensitivity of 0.07 microU/ml. Serum TSH was immunologically identical to standard TSH and did not decrease during a T3 suppression test. Serum free alpha-subunit and the molar alpha-subunit to TSH ratio were high (6.1 ng/ml and 31.2, respectively). TRH administration induced significant increases in both GH (+129%) and alpha-subunit (+156%) levels. Conversely, dopamine infusion resulted in a decrease in serum GH (-66%) and alpha-subunit (-43%) levels, and subsequent administration of the dopamine antagonist sulpiride induced significant increases in both GH and alpha-subunit (+393% and +106%, respectively). Similarly, somatostatin infusion inhibited GH (-43%) and alpha-subunit (-61%) secretion. Serum TSH levels were not affected by TRH, dopamine, or somatostatin. The biological to immunological activity ratio of serum TSH purified by immunoaffinity chromatography and measured in an adenylate cyclase assay was significantly increased compared to that in serum from hypothyroid or euthyroid subjects [biological to immunological activity ratio, 6.9 +/- 0.2 (+/- SD) vs. 4.4 +/- 1.1; P less than 0.001]. In gel chromatography, the apparent mol wt of the patient's TSH was smaller than that of the controls. After adenomectomy, all of the altered parameters of pituitary function became normal. Double gold particle immunostaining of the adenomatous tissue showed that all of the cells contained secretory granules positive for GH and alpha-subunit, while very few cells were positive for TSH beta as well as GH and alpha-subunit. These data indicate that in this patient serum TSH had an apparent mol wt smaller than that of normal TSH and an increased biological activity which, along with the autonomous TSH secretion, account for hyperthyroidism in the presence of low normal TSH levels; alpha-subunit originated from the same adenomatous cells that secreted GH but not TSH, thus explaining the in vivo observation that alpha-subunit responses to several agents were dissociated from TSH responses and parallel to GH responses; and TSH and GH were colocalized in a minority of the neoplastic cells.

Adenoma

Iopamidol for intrathecal use in pediatric neuroradiology.

A clinical trial using iopamidol, a non-ionic contrast medium, in various iodine concentrations (300, 200 and 150 mg I/ml), was carried out in 947 children, aged between 1 day and 14 years, who underwent various neuroradiologic procedures: computed tomography (CT) cisternography (n = 307), CT ventriculography (n = 203), CT myelography (n = 153), and conventional myelography (n = 284). No significant variation in vital signs and neurologic status was recorded during and up to 72 hours after the examination. Psychic agitation was the major effect registered, being clearly related to the type of procedure used. A significant reduction of untoward side effects (about 50%) was observed using the lower concentrations of the medium. Iopamidol 150 mg and 200 mg represented the optimal concentration for CT enhancement, these concentrations reducing artifacts; the 300 mg I/ml concentration gave best results in conventional radiology. It seems that the lower concentrations of iopamidol (200 and 150 mg I/ml) can be usefully employed in pediatric neuroradiology, with preserved contrast and dramatically reduced untoward reactions.

Adolescent

Iopamidol 150. A low iodine content non-ionic water-soluble contrast medium for CT myelocisternography.

Results of a clinical trial in CT myelocisternography performed with a new reduced concentration of iopamidol (150 mg I/ml) are reported. This compound is characterized by very low osmolality and osmotic pressure close to those of blood and CSF. Thirty patients were examined. Before, during and after the procedure pulse rate and blood pressure were recorded, EEG was taken and neurologic examination performed. After the examination no alteration in these parameters was recorded. The demonstration of the subarachnoid space and related structures was invariably adequate for diagnosis. In no case was a repeat study using a higher concentration of contrast medium needed. Mild reactions occurred only in three patients (10%). The authors conclude that iopamidol 150, owing to its safety and good imaging capacity, is useful in CT imaging of the subarachnoid space.

Adolescent

Side effects during therapy with low dosage amiodarone.

Amiodarone is a very active antiarrhythmic agent, but true incidence of Amiodarone-related side effects is still questionable. In a prospective trial of 400 or 200 mg of Amiodarone day for 56 days in 58 patients, we monitored thyroid and liver function, blood count, chest x-ray, ecg. In addiction we took regularly notice of subjective disturbances and physical signs. Side effects were: conduction disturbances 6%, bradycardia less than 50/min. 2%, gastrointestinal 12%, sleep disorders 12%, hyperthyroidism 4,15% and hypothyroidism 6.25%. Blood levels of Amiodarone and desethylamiodarone were not predictive of side effects. Noteworthy was the absence of cutaneous and pulmonary side effects. On the other hand, thyroid function should be monitored carefully because disfunction is not rare (10.4%) and in the case of hyperthyroidism could be related to worsening of arrhythmias.

Adolescent

Effect of intracarotid injection of iopamidol on local cerebral glucose utilization in rat brain.

We assessed, by means of the [14C]-2-deoxy-D-glucose autoradiography method, the effect of intracarotid injection of a nonionic, low-osmolar contrast medium (iopamidol) on local cerebral glucose utilization in the rat brain. Contrast medium was injected at 20 degrees C and at 37 degrees C, and the relative changes in local cerebral glucose utilization were measured. At 20 degrees C the viscosity of the contrast agent was about twice that of the same solution at 37 degrees C, and resulted in a statistically significant increase in local cerebral glucose utilization in the hemisphere ipsilateral to the side of intracarotid infusion. Saline control studies showed that the metabolic change was not related to either the solution temperature or the osmolality. These findings suggest that increased viscosity of a contrast medium may contribute to its neurotoxic effects during cerebral angiography, hence emphasizing the importance of preheating contrast material to avoid adverse reactions.

Animals

[Selective coronarography and left ventriculography using iopamidol in the early phase of myocardial infarct].

The new techniques for an early treatment of acute myocardial infarction (AMI), such as thrombolysis and percutaneous transluminal angioplasty, often necessitate rapid and accurate radiological evaluation of coronaric lesions and left ventricular function. The aim of the present study was to evaluate both safety and tolerability of selective coronarography (SC) and left ventriculography (LVG), with iopamidol 370 mg I/ml as a contrast medium, in the acute phase of AMI. Thirty-nine patients aged 26-29 years, were examined: 18, group A, within 4 days (mean 2.6 +/- 0.8 SD) and 21, group B, within 5-15 days after AMI (mean 8.8 +/- 3 SD). Contrast media (cm) dosage varied from 150 to 300 ml (2.43-5.5 ml/bw). During the procedure, ECG was continuously recorded; left ventricular pressure was registered immediately before and 30 minutes after cm administration. During the following 9 days ECG tracings and plasmatic cytolysis enzymes were monitored. During the examinations no patient complained of any symptoms. After LVG slight elevations in end diastolic pressure were detected in all patients (mean increase 4.7 mmHg), which were not relevant from a clinical point of view. In 11/39 cases ventricular tachycardia was observed, which spontaneously ceased. During SC no change in ECG tracings was registered except in one patient, group A, in whom complete transitory heart block was detected. After SC no alteration in instrumental and biochemical parameters was registered except in one patient, group B, in whom a reinfarction due to right coronaric artery occlusion was observed. In conclusion, our results suggest that both SC and LVG with iopamidol are safe techniques also in the early phase of myocardial infarction.

Adult