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Biomedical subjects

M Boscaro

Publications and source records attributed to M Boscaro.

At least 73 records · Page 4Linked to original sources
PubMed1994

Abnormality of aldosterone and cortisol late pathways in glucocorticoid-remediable aldosteronism.

Patients with glucocorticoid-remediable aldosteronism (GRA) possess a chimeric gene resulting from fusion of the genes encoding steroid aldosterone synthase and 11 beta-hydroxylase. In the adrenal zona fasciculata, this may lead to ectopic expression under ACTH control of aldosterone synthase activity and increased formation of cortisol C18 oxidation products. We assessed mineralocorticoid and glucocorticoid pathways in three patients with GRA. Baseline plasma progesterone, 17 alpha-hydroxyprogesterone, corticosterone, and cortisol were normal in all patients, whereas 11-deoxycorticosterone, aldosterone, and 11-deoxycortisol were above normal. The ratios of both corticosterone/11-deoxycorticosterone and cortisol/11-deoxycortisol were abnormally low, and decreased further 60 min after administration of ACTH-(1-24) (250 micrograms) as an i.v. bolus. A low corticosterone/11-deoxycorticosterone ratio is consistent with an increased aldosterone synthase activity forming aldosterone by corticosterone. Similarly, a decreased cortisol/11-deoxycortisol ratio could reflect enhanced cortisol C18 oxidation. Our findings are in agreement with a hyperfunction of the 11 beta-hydroxylase/aldosterone synthase complex in the adrenal zona fasciculata of GRA induced by the new chimeric gene.

Adrenocorticotropic Hormone↗
PubMed1994

Left ventricular structural characteristics in Cushing's syndrome.

The aim of the present study was to assess structural characteristics of the left ventricle by echocardiography in a group of patients with Cushing's syndrome compared with a control population. Eighteen patients with Cushing's syndrome and 18 controls, matched for sex, age, body weight, body surface area, blood pressure (BP) and duration of hypertension were investigated by M-mode (2-D derived) echocardiography. In each of the two groups, 11 of 18 subjects were hypertensive. Relative wall thickness (RWT) was above normal (> 0.45) in 11 (five normotensive and six hypertensive) of 18 patients with Cushing's syndrome and in two (hypertensive) of 18 controls. Left ventricular mass index was abnormal in three (one normotensive and two hypertensive) patients with Cushing's syndrome and in four hypertensive controls. All other systolic function indices were within normal and similar in both groups. No correlation was found between RWT and BP as well as between RWT and urinary cortisol levels in patients with Cushing's syndrome. A significant correlation was found between RWT and duration of disease. Echocardiography after successful surgery showed normalisation of RWT in five of six patients in whom it was previously abnormal. Our data suggest that time factor, i.e. long-lasting exposure to increased cortisol, rather than hormone or BP levels is the most relevant determinant of left ventricular concentric remodeling in patients with Cushing's syndrome.

Adolescent↗
PubMed1993

Effects of a calcium antagonist on the pituitary-adrenal axis.

It has been proposed that calcium is involved, as second messenger, in the regulation of various pituitary hormones including ACTH. Several evidences indicate that calcium-entry blockers agents (i.e. nifedipine) inhibit oCRH-dependent ACTH stimulation "in vitro". To further investigate these aspects we tested the effects of a calcium antagonist nitrendipine on basal and oCRH-stimulated ACTH secretion, in 6 hypertensive patients, with normal hypothalamus pituitary adrenal axis. Nitrendipine 20 mg per os once daily for 30 days, was efficacious in lowering blood pressure but did not modify ACTH and cortisol response to oCRH (200 micrograms i.v.), in spite of a minor inhibitory effect on the concomitant aldosterone response. These data indicate that ACTH secretion is not significantly modified by calcium antagonists, which can exert a detectable effect on adrenal zona glomerulosa.

Adrenocorticotropic Hormone↗
PubMed1993

A role for life events in the pathogenesis of Cushing's disease.

OBJECTIVE: We have previously reported on 30 patients with Cushing's syndrome suggesting an aetiological role for stressful life events. The investigation about life events in the year before the first signs of disease onset was extended to a larger population of patients with Cushing's syndrome, allowing us to differentiate patients with pituitary-dependent and pituitary-independent forms. DESIGN: Case-control study. PATIENTS: Sixty-six consecutive patients with Cushing's syndrome of various aetiologies (46 with pituitary-dependent forms and 20 with primary adrenal hyperfunction or ectopic ACTH production) and a control group of 66 healthy subjects, matched for sociodemographic variables, were studied. MEASUREMENTS: Paykel's Interview for Recent Life Events (a semistructured research interview covering 64 life events) was administered after the acute phase of illness while in remission. RESULTS: Patients with Cushing's syndrome reported significantly more stressful life events (P < 0.001), both events that had an objective negative impact (P < 0.001) and independent events (P < 0.001), than controls, confirming previous findings. Patients with pituitary-dependent Cushing's disease were compared with their matched controls and reported significantly more total events, events with an objective negative impact and independent events (all at P < 0.001). There were no significant differences between patients with pituitary-independent forms and their matched controls. CONCLUSIONS: These findings indicate a causal role for stressful life events exclusively in pituitary-dependent Cushing's disease, and suggest a limbic-hypothalamic involvement in the pathogenesis of this condition. The results are similar to those obtained in major depression, and add to other analogies between the two disorders.

ACTH Syndrome, Ectopic↗
PubMed1993

Response of hypertension to conventional antihypertensive treatment and/or steroidogenesis inhibitors in Cushing's syndrome.

OBJECTIVES: To evaluate the effect of conventional antihypertensive drugs and/or inhibitors of steroid production in the management of hypertension in Cushing's syndrome. DESIGN: A retrospective open clinical study with pre- and post-treatment assessment. SETTING: A university hospital, where patients were initially admitted and then followed-up in an ambulatory clinic over a period of 6 years. SUBJECTS: Forty consecutive hypertensive patients with Cushing's syndrome. INTERVENTIONS: Patients were divided into two groups according to the different management of hypertension. The first group (group 1) of 28 patients included those treated with antihypertensive drugs at full dose (diuretics, calcium antagonists, angiotensin converting enzyme [ACE] inhibitors, as single agents or in combination). The second group (group 2) of 12 patients received ketoconazole alone. MAIN OUTCOME MEASURES: Blood pressure variations compared to pre-treatment levels. RESULTS: Blood pressure normalization was obtained in four of the 28 patients of group 1. In 12 of the remaining patients, ketoconazole, an inhibitor of steroid production, was subsequently added and this normalized blood pressure in all but the one in whom cortisol was not decreased. In the 12 patients of group 2, ketoconazole alone lowered blood pressure within normal limits in all but one who had long-standing hypertension. CONCLUSIONS: In hypertensive patients with Cushing's syndrome, conventional antihypertensive therapy is mostly ineffective. Blood pressure response is satisfactory only after the restoration of normal cortisol levels, indicating the need for a specific treatment for hypertension in this disorder.

Adult↗
PubMed1993

Quality of life of hirsute women.

Hirsutism is recognized to cause profound distress in affected women, due to cosmetic and psychosexual implications. It was evaluated in the present study by methods found to be valid and reliable in psychosomatic research. Fifty women with hirsutism belonging to the spectrum of disorders from idiopathic hirsutism to polycystic ovary syndrome, after complete medical work-up, underwent the same psychometric evaluation as 50 healthy non-hirsute women, matched for sociodemographic variables. Hirsute women had a Ferriman and Gallwey score ranging from 8 to 19. Psychometric evaluation for quality of life was carried out by the following methods: (a) Kellner's Brief Problem List, a 12 item self-rating list of psychosocial problems; (b) Kellner's Symptom Rating Test (SRT), a 46 item self-rating scale that yields a total score of distress as well as six subscales (anxiety, depression, somatic symptoms, anger-hostility, cognitive and psychotic symptoms); and (c) Marks' Social Situations Questionnaire (SSQ), a 30 item self-rating scale concerned with social phobia. Patients with hirsutism displayed significantly higher social fears at the SSQ than controls (P < 0.01). They also showed more anxiety (P < 0.01) and psychotic symptoms (P < 0.01) at the SRT, whereas there were no significant differences in depression, somatization, anger-hostility and cognitive symptoms. These results suggest that the complex management of hirsute women, in addition to pharmacological and/or cosmetic measures, may require specific psychotherapy.

Adolescent↗
PubMed1993

Course of depression in Cushing's syndrome: response to treatment and comparison with Graves' disease.

Depression in a common, life-threatening complication of Cushing's syndrome and may occur in several other endocrine disorders. It is not clear, however, whether distinct features pertain to hypercortisolism. We studied depression in Cushing's syndrome differentiating pituitary-dependent and pituitary-independent forms, its incidence compared to Graves' disease, and its appearance in the prodromal phase of both conditions. To 66 consecutive patients with Cushing's syndrome and 70 with Graves' disease, after treatment, a semistructured interview for depressive symptoms based on Paykel's clinical interview for depression was administered. In Cushing's syndrome, the response of depression to normalization of urinary cortisol levels was evaluated by Kellner's global rating method. There was a significant difference in the occurrence of depression (p < 0.001) between Cushing's syndrome (62%) and Graves' disease (23%). Depression appeared in the prodromal phase in 27% of patients with Cushing's syndrome and in 14% of those with Graves' disease, but the difference was not significant. In Cushing's syndrome, there were no significant differences in depression between patients with pituitary-dependent (n = 41) and pituitary-independent (n = 20) forms, or in their response to treatment. About 70% of patients fully recovered from their depression, whereas there was no substantial change in the others and even worsening in 2. Our findings in Cushing's syndrome and Graves' disease are in agreement with previous investigations using specific diagnostic criteria for depression. We found a tendency for this symptom to manifest in the prodromal phase of both illnesses. An endocrine etiology should be, therefore, considered in depressed patients not responding to standard psychiatric treatment.

Adult↗
PubMed1993

Effects of inhaled beclomethasone on airway responsiveness in occupational asthma. Placebo-controlled study of subjects sensitized to toluene diisocyanate.

We investigated the effect of 5 months of treatment with inhaled beclomethasone dipropionate (BDP) on the airway responsiveness to methacholine (PD20 FEV1) and to toluene diisocyanate (TDI) in 15 sensitized asthmatic subjects who had been removed from occupational exposure to TDI. After the diagnosis was established by a positive inhalation challenge with TDI, each subject was removed from occupational exposure to isocyanates and treated with either BDP (1 mg twice per day, n = 7) or placebo (n = 8) for 5 months. The study was double blind for parallel groups. P20 FEV1 methacholine was measured before and three times during treatment and then at 6 months, that is, 4 wk after cessation of treatment. Airway sensitivity to TDI was assessed with specific inhalation challenge before treatment and at 6 months. Beclomethasone reduced the airway hyperresponsiveness to methacholine but did not affect the response to TDI. In fact, in the subjects on BDP, P20 FEV1 increased from 0.145 to 0.485 mg (p < 0.05) after 2 months of treatment. A further increase was observed at 4 and 5 months (0.548 and 0.629 mg, respectively, p < 0.01), and the improvement in nonspecific airway responsiveness was maintained after a 1-month washout period (0.637 mg, p < 0.01). In contrast, in the subjects on placebo, P20 FEV1 did not change significantly. At the end of the study, the severity of asthmatic reactions induced by bronchial challenge with TDI was significantly reduced in both groups, but no differences were observed between placebo and BDP.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Association of somatotrophinomas with loss of alleles on chromosome 11 and with gsp mutations.

The molecular pathology of somatotrophinomas has been investigated by a combined search for dominant mutations of the gene encoding the Gs alpha protein and for recessive mutations involving chromosome 11q13, which contains the gene causing multiple endocrine neoplasia type 1 (MEN1). Somatotrophinomas and peripheral leukocytes were obtained from thirteen patients with acromegaly; one patient also suffered from MEN1. Five DNA probes identifying restriction fragment length polymorphisms from 11q revealed allele loss in pituitary tumors from five (four non-MEN1 and one MEN1) patients. Deletion mapping revealed that the region of allele loss common to the somatotrophinomas involved 11q13. An analysis for similar allelic deletions at 12 other loci from chromosomes 1-5, 7-9, 12-14, and 17 did not reveal generalized allele loss in the somatotrophinomas. These results, which represent the first report of chromosome 11 allele loss occurring in non-MEN1 somatotrophinomas, indicate that a recessive oncogene on 11q13 is specifically involved in the monoclonal development of somatotrophinomas. In addition Gs alpha mutations were detected in two non-MEN1 somatotrophinomas, one of which also revealed allele loss of chromosome 11. Thus, our results reveal that the development of somatotrophinomas is associated with alterations in both dominant and recessive oncogenes and further characterization of these genetic abnormalities will help to elucidate the multistep etiology and progression of somatotrophinomas.

Acromegaly↗
PubMed1993

Life events in the pathogenesis of Graves' disease. A controlled study.

Contradictory findings have been reported about a possible causal relationship of life stress to Graves' disease. We evaluated this issue by investigating the occurrence of stressful life events in the year before the first signs of disease onset, using methods that have been found to be valid and reliable in psychosomatic research. Seventy consecutive patients with Graves' disease and a control group of 70 healthy subjects, matched for sociodemographic variables, were studied. Paykel's Interview for Recent Life Events (a semistructured research interview covering 64 life events) was administered to patients, not during the acute phase of illness but while on remission, by antithyroid drug treatment. Patients with Graves' disease reported significantly more life events compared to controls (p < 0.001). They also had more independent events (p < 0.001) and events that had an objective negative impact (p < 0.001) according to an independent rater, unaware whether the events had occurred in patients or controls. All categories of events were found to be significantly more frequent in patients suffering from Graves' disease than in controls. By rigorous methods (inclusion of patients with Graves' disease only, careful dating of the onset of symptoms, accurate event definition, delay of the interview upon disease remission, use of a blind rater for judging independence and objective negative impact), our results support the concept of an excess of life events in Graves' disease. Stressful life events may affect the regulatory mechanisms of immune function in a number of ways. Within the extreme complexity of the phenomena implicated in the pathogenesis of autoimmune thyroid hyperfunction, our findings emphasize the role of emotional stress.

Adolescent↗
PubMed1993

Combined haemophilia A and type I von Willebrand's disease: a family study including an evaluation of the effects of DDAVP infusion.

A family with concurrent haemophilia A and type I von Willebrand's disease (vWd) is described. The propositus was affected by both disorders. The propositus' mother was an obligate carrier of haemophilia A being the daughter of a haemophilic. The father and sister were affected by vWd. The sister was also a possible carrier of haemophilia A. This is the first report of both disorders occurring simultaneously. The infusion of 1-desamino-8-d-arginine vasopressin (DDAVP) induced, in the propositus, a normalization of circulating levels of vWf, with a less pronounced enhancement of factor VIII:C. In the father, the response to DDAVP infusion of factor VIII/vWf complex was normal. In the mother, the time-course of factor VIII:C was characterized, after a peak at 30 min, by a progressive decrease until 2 hours after infusion, in contrast to vWf which appeared further increased at the same times. Therefore, the low factor VII:C/vWf:Ag ratio, already present before infusion, became significantly more pronounced 2 hours after DDAVP. Similar findings were observed in another obligate carrier of the family, in the propositus' sister and in 10 other haemophilia A carriers, belonging to different kindreds. In all patients, even when the basal factor VIII:C/vWf:Ag ratio was normal, two hours after DDAVP it decreased in agreement with the haemophilia A carrier state.

Adult↗
PubMed1992

Acute and chronic effects of high glucocorticoid levels on hypothalamic-pituitary-thyroid axis in man.

It is known that glucocorticoids can influence anterior pituitary hormones other than ACTH. Their effects on the hypothalamic-pituitary-thyroid axis are controversial. To further investigate this issue, the acute and chronic effects of high plasma cortisol levels on TSH secretion were evaluated in 20 normal subjects and in 14 patients with Cushing's syndrome. In normals, high plasma cortisol levels were obtained by giving ACTH 250 micrograms or CRH 100 micrograms iv as a bolus or by an hydrocortisone 500 mg infusion over 1 h. Acute cortisol increase produced no effect both on basal and TRH-stimulated TSH secretion. In patients with Cushing's syndrome, basal TSH levels, low or suppressed, showed an impaired response to TRH, inversely correlated with urinary cortisol values. After successful surgery, TSH and its response to TRH became normal in concomitance with the normalization of plasma and urinary cortisol levels. Our data show the lack of an acute inhibitory effect of high plasma cortisol levels on TRH-TSH axis. However, after long-term exposure to high plasma cortisol levels, i.e. Cushing's syndrome, inhibition of both basal and TRH-stimulated TSH secretion was demonstrated. These findings indicate that only prolonged hypercortisolism does interfere with pituitary TSH secretion. The underlying mechanisms are still unclear.

Adrenocorticotropic Hormone↗
PubMed1992

Glucocorticoid-dependent hypertension.

Glucocorticoid (GC) excess (Cushing's syndrome) is associated with hypertension in at least 70% of patients (in our series 89/130), independently of the subtype (pituitary or adrenal) and the duration, but not of the age of the patients. Cardiovascular damage is quite frequent in hypertensives, but is sometimes also present in normotensives. The mortality of patients with Cushing's syndrome is four times that of the general population when matched for age and sex, and much of this excess mortality is caused by cardiovascular disease. Hypertension remits in most of the patients after successful treatment, but may persist in some. Hypertension also occurs in 20% of patients treated with GC orally. The type of hypertension is independent of salt uptake, can not be controlled by spironolactone but is inhibited by a GC antagonist such as RU486. Experimentally-induced hypertension with oral cortisol (F) is associated with a rise in cardiac output, a fall in calculated total peripheral resistance, an increased forearm vascular responsiveness to exogenous norepinephrine, but no change in overall sympathetic tone, or in norepinephrine reuptake. The increased pressor responsiveness is probably due to local postsynaptic effector mechanisms in the resistance vessels, which could be important in phasic increases in neuronally mediated constrictor responses. Both in patients with Cushing's syndrome and in those on chronic GC treatment, the circadian blood pressure variations are absent or reversed. This may contribute to the deleterious effects of the GC excess on blood vessels. The vascular effects of the GC may be mediated by the activation of specific cardiovascular receptors, by modulating vascular transport systems, or by altered catecholamine or prostaglandin metabolism. GC may also act as mineralocorticoids (MC): in fact type 1 MC receptors are unable, in vitro, to distinguish between aldosterone and cortisol. The specificity-conferring mechanism of typical target organs for MC (e.g. kidney)--is thought to be due to the action of local 11-beta-hydroxysteroid dehydrogenase, which converts F to biologically inactive cortisone (E). When the activity of the enzyme is impaired (syndrome of apparent MC excess, liquorice or carbenoxolone administration), F acts as a MC and MC-hypertension with hypokalemia occurs.(ABSTRACT TRUNCATED AT 400 WORDS)

Cushing Syndrome↗
PubMed1992

The fibrinolytic potential in patients with Cushing's disease: a clue to their hypercoagulable state.

The aim of our study was to determine the fibrinolytic potential in a large group of patients with Cushing's disease. These patients had a significant shortening of the activated partial thromboplastin time and increase in factor VIII/von Willebrand factor complex compared to normal controls. The mean levels of plasminogen, tissue plasminogen activator (t-PA) antigen and plasminogen activator inhibitor (PAI) activity were significantly higher than in normal subjects, whereas the basal fibrinolytic activity was similar to that seen in the control group. In 17 out of 30 Cushing patients and in 17 normal subjects the fibrinolytic potential was determined with the venous occlusion test. In the Cushing group, the release of t-PA antigen after 20 min of venous occlusion was comparable to that observed in the control group. However, Cushing patients showed a lower fibrinolytic activity than normal subjects, since a lesser shortening of the euglobulin lysis time and a non-significant rise of plasminogen activator activity levels were found. Moreover, in these patients the PAI activity values remained unchanged and significantly increased after venous occlusion test also. In conclusion, the impaired fibrinolytic activation seen in Cushing patients after venous occlusion can be explained by the inhibitory effect of the high PAI levels on plasminogen activators. The defective fibrinolytic potential could further contribute to the hypercoagulable state in Cushing's disease. High PAI levels before surgery may represent an additional risk factor for post-surgical thromboembolic complications in Cushing patients.

Adult↗
PubMed1992

Increase in vascular permeability produced in rat airways by PAF: potentiation by adrenalectomy.

1. The effect of bilateral adrenalectomy on the sensitivity of blood vessels in rat airways to mediators that increase vascular permeability was examined. 2. An increase in vascular permeability was induced by intravenous platelet activating factor (PAF, 50, 100, 500, 1000 ng kg-1) and measured by quantifying the extravasation of Evans blue dye. 3. PAF consistently increased the amount of Evans blue extravasation in the larynx, trachea, main bronchi and intrapulmonary airways in sham-operated rats. 4. The magnitude of this extravasation was significantly greater in the larynx (P less than 0.05), trachea (P less than 0.05) and main bronchi (P less than 0.05) of the adrenalectomized rats than it was in these tissues of the sham-operated rats. 5. When adrenalectomized rats were given subcutaneous dexamethasone (0.2 mg kg-1 4 h before PAF) the amount of plasma extravasation produced by PAF was decreased to the level of the sham-operated rats. 6. We conclude that adrenalectomy potentiates the increase in airway vascular permeability induced by PAF in rats and that this effect may be due to the depletion of endogenous corticosteroids.

Adrenalectomy↗
PubMed1992

Selective venous sampling in the differential diagnosis of ACTH-dependent Cushing's syndrome.

Bilateral simultaneous inferior petrosal sinus sampling, associated with the oCRH stimulation test (100 micrograms i.v. as a bolus) was performed in 22 patients with Cushing's syndrome and no signs of pituitary abnormalities. Catheters were inserted into both femoral veins. More than one site in the superior and inferior vena cava was sampled before reaching the inferior petrosal sinuses. Blood samples for ACTH and beta-endorphin were gently aspirated from both petrosal sinuses and from a peripheral vein simultaneously. Blood was drawn at 0, 5, 10 and 15 min after oCRH injection. Seventeen of 22 patients showed an ipsilateral to peripheral vein ratio higher than 1.5, and 12 patients showed a lateralization of ACTH levels after oCRH stimulation. Seventeen patients underwent transsphenoidal pituitary surgery. Nine patients had a pituitary adenoma at the expected side; 1 at the contralateral side, while in 2 it was central. Three of 4 patients in whom the ipsilateral/peripheral ratio was less than 1.5 had the highest ACTH levels at the superior or inferior vena cava, not responsive to oCRH stimulation. One of these had a mediastinal and one a pulmonary mass. The third one, with an occult ectopic source, is still under investigation. At immunohistochemical and biological in vitro studies, both tumors were shown to secrete ACTH. In 13 patients in whom both beta-endorphin and ACTH measurements were performed, these hormones showed similar patterns of response. In conclusion, simultaneous bilateral petrosal sinus catheterization is a useful tool in the differential diagnosis of Cushing's syndrome as concerning pituitary and ectopic forms.(ABSTRACT TRUNCATED AT 250 WORDS)

ACTH Syndrome, Ectopic↗