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F Mantero

Publications and source records attributed to F Mantero.

At least 37 records · Page 2Linked to original sources
PubMed2003

Does dynamic testing have a place in the modern assessment of endocrine hypertension?

Hypertension is one of the most important public health problems, affecting 15-20% of the adult population. The so-called "essential" hypertension includes the majority of cases; however, endocrine hypertension should always be suspected and excluded by physicians for at least 2 important reasons: prevalence rates of primary aldosteronism (the most common cause of mineralocorticoid-based hypertension) among hypertensives seem to be much higher than < 1% of initial studies, and treatment of endocrine hypertension relies on specific drugs (1) or on surgery. Endocrine hypertension comprises a spectrum of diseases (Table 1).

Cushing Syndrome↗
PubMed2002

Unusual clinical manifestation of pheochromocytoma in a MEN2A patient.

A case of unusual clinical manifestation of pheochromocytoma in a type 2A multiple endocrine neoplasia (MEN2A) patient is presented. A 27-year-old man affected by MEN2A syndrome, complaining of anxiety and depression, was admitted in our Division. Past medical history included a total thyroidectomy for medullary carcinoma in 1985, and left adrenalectomy for pheochromocytoma in 1994. Blood pressure was 130/ 85 mmHg without orthostatic hypotension and pulse rate was 72 beats/min. Laboratory data revealed thyroid hormones and carcinoembryonic antigen (CEA) in the normal range and high basal serum calcitonin levels (158 pg/ml). Plasma catecholamines and vanillylmandelic acid resulted in normal levels but epinephrine/norepinephrine ratio was elevated (0.65). The glucagon stimulation test showed positive clinical and biochemical response. Magnetic resonance imaging (MRI) and meta-iodobenzylguanidine (MIBG) scintiscan confirmed the presence of bilateral adrenal masses. Bilateral adrenalectomy by laparoscopic anterior approach was performed. Histology was consistent with adrenal pheochromocytomas. After surgical approach, psychiatric findings disappeared and did not recur at follow-up in spite of no medication for two years. In conclusion, bilateral pheochromocytoma is more frequent in MEN2A syndrome and probably understimated if the follow-up is not prolonged. In these cases clinical features are often aspecific and basal hormonal data may be normal in a great number of patients. Therefore long-term observation is justified in these patients. Pheochromocytoma was described as the "great mimic" for the numerous subjective manifestations. Differential diagnosis among typical features of neuropsychiatric disorders and pheochromocytoma must be considered.

Adrenal Gland Neoplasms↗
PubMed2002

Comparison of circulating and local adipose tissue renin-angiotensin system in normotensive and hypertensive obese subjects.

The renin-angiotensin-aldosterone system (RAAS) plays a well-recognized role in the regulation of BP and in salt and water balance. Since hypertension affects a considerable proportion of obese patients, circulating RAAS has been studied in obese subjects with and without hypertension, albeit with conflicting results. Furthermore, attention has recently focused on the expression of the components of the Renin-angiotensin system (RAS) in some organs, including adipose tissue where it seems to be involved in the regulation of growth and differentiation. The aim of our study was to investigate circulating RAAS and adipose tissue RAS in obese patients with and without hypertension and in matched controls. PRA, and plasma and urinary aldosterone levels were measured in 35 obese, 30 hypertensive obese patients and in 20 controls. In addition, the expression of angiotensinogen (AGT) and angiotensin II type 1 receptor (AT1) genes was studied in sc adipose tissue from 8 obese, 6 hypertensive obese and 6 healthy subjects. As previously demonstrated in other studies, there were no significant differences in the levels of circulating RAAS components in the 3 groups. As regards local RAS, interestingly, we found that AT1 gene was significantly more expressed in sc adipose tissue from obese patients with hypertension than in those without hypertension and controls. By contrast, AGT levels were similar in the 3 groups. Our data do not support the hypothesis of an involvement of circulating RAAS in the development of obesity-related hypertension. On the other hand, local RAS seems to be differently regulated in sc adipose tissue from obese patients with hypertension with respect to normotensive obese patients and controls.

Adipose Tissue↗
PubMed2002

Coenzyme Q10 levels in idiopathic and varicocele-associated asthenozoospermia.

Levels of coenzyme Q10 (CoQ10) and of its reduced and oxidized forms (ubiquinol, QH2, and ubiquinone, Qox) have been determined in sperm cells and seminal plasma of idiopathic (IDA) and varicocele-associated (VARA) asthenozoospermic patients and of controls. The results have shown significantly lower levels of coenzyme Q10 and of its reduced form, QH2, in semen samples from patients with asthenospermia; furthermore, the coenzyme Q10 content was mainly associated with spermatozoa. Interestingly, sperm cells from IDA patients exhibited significantly lower levels of CoQ10 and QH2 when compared to VARA ones. The QH2/Qox ratio was significantly lower in sperm cells from IDA patients and in seminal plasma from IDA and VARA patients when compared with the control group. The present data suggest that the QH2/Qox ratio may be an index of oxidative stress and its reduction, a risk factor for semen quality. Therefore, the present data could suggest that sperm cells, characterized by low motility and abnormal morphology, have low levels of coenzyme Q10. As a consequence, they could be less capable in dealing with oxidative stress which could lead to a reduced QH2/Qox ratio. Furthermore, the significantly lower levels of CoQ10 and QH2 levels in sperm cells from IDA patients, when compared to VARA ones, enable us to hypothesize a pathogenetic role of antioxidant impairment, at least as a cofactor, in idiopathic forms of asthenozoospermia.

Coenzymes↗
PubMed2002

Role of seminal osmolarity in the reduction of human sperm motility.

Mammalian sperm at ejaculation are suspended in the seminal plasma, a heterogeneous mixture deriving from the testicular/epididymal fluid and from secretions of seminal vesicles, prostate and bulbourethral glands. Biochemical characteristics of seminal fluid change along the male reproductive tract when considering its inorganic and organic composition and pH but it is known that in each region of the male genital tract seminal osmolarity is higher than that of serum. It has been previously demonstrated that in invertebrate and vertebrate sperm, seminal plasma osmolarity influences sperm motility and activity, and human sperm have been shown to possess osmosensitive calcium entry pathway that controls important functions such as acrosome reaction and oocyte penetration. In the present study, we have determined seminal plasma osmolarity in a large number of normozoospermic fertile and asthenozoospermic infertile subjects correlating it with sperm motility percentages and kinematic characteristics determined utilizing a computerized motion analysis system. Our results confirm that seminal plasma osmolarity is higher than that of serum (336.1 +/- 20.2 vs. 291.1 +/- 6.9 mOsm/L, respectively). Normozoospermic subjects show seminal osmolarity values that are significantly lower with respect to asthenozoospermic patients (317.8 +/- 12.2 vs. 345.2 +/- 22.6 mOsm/L, p<0.001), irrespective of the cause of asthenozoospermia. Seminal plasma osmolarity negatively correlates with sperm progressive motility percentages and kinetic characteristics (curvilinear velocity, linear velocity, linear coefficient and lateral displacements of sperm head). Furthermore, when sperm from fertile subjects were suspended in medium with an osmolarity increasing from 300 to 600 mOsm, sperm motility percentages and kinetics characteristics were progressively reduced and nearly abolished when medium osmolarity was 600 mOsm. On the contrary, when sperm from asthenozoospermic subjects with high semen osmolarity were resuspended in medium with lower osmolarity, sperm motility parameters improved significantly. Sperm motility parameters did not correlate with seminal plasma concentrations of sodium, potassium, chloride with a weak correlation only with seminal calcium concentration. No correlations are present between seminal plasma osmolarity and ionic composition. In conclusion, the present study confirms and extends the knowledge that, in human, seminal plasma osmolarity is higher than that of serum and demonstrates that seminal osmolarity influences sperm motility characteristics and then it may contribute to the pathogenesis of some forms of asthenozoospermia and male infertility.

Humans↗
PubMed2001

Congenital deficiency of 11beta-hydroxysteroid dehydrogenase (apparent mineralocorticoid excess syndrome): diagnostic value of urinary free cortisol and cortisone.

The syndrome of apparent mineralocorticoid excess (AME) is an inherited form of hypertension. This disorder results from an inability of the enzyme 11beta-hydroxysteroid dehydrogenase (11beta-OHSD) to inactivate cortisol to cortisone. The diagnosis of AME is usually based on an elevated ratio of cortisol to cortisone reduced metabolites in the urine [tetrahydrocortisol plus allotetrahydrocortisol to tetrahydrocortisone (THF+alloTHF/THE)]. The principal site of "A" ring reduction is the liver, but AME arises from mutation in the gene encoding 11beta-OHSD2 in the kidney. We used a gas chromatographic/mass spectrometric method to measure the urinary free cortisol (UFF) and free cortisone (UFE) in 24 patients affected by the two variants of AME [19 with the classical form (type I) and 5 with the mild form called AME type II] in order to provide a more reproducible in vivo measure of the renal enzymatic activity. Type I patients were divided into two groups: children under 12 and adults. UFF levels (microg/24 h) did not differ between under-12 controls and AME type I children (mean+/-SD, 9+/-4 and 15+/-12, respectively), but was significantly higher in affected adults compared to controls: (62+/-32 vs 29+/-8, p<0.01). No differences were found between adult controls and AME type II patients (29+/-8 and 37.0+/-14, respectively). UFE was undetectable in 63% of AME type I and significantly lower in AME type II (p<0.05). As a consequence UFF/UFE ratio was significantly higher in AME type I patients both in children and adults compared to controls (AME children: 5.1+/-2.6; normal children: 0.43+/-0.2, p<0.01; AME type I adults: 17.7+/-19.6; normal adults: 0.54+/-0.3 p<0.01). For AME type II, where UFE was detectable in every case, the UFF/UFE ratio was significantly higher than adult controls (2.75+/-1.5 vs 0.54+/-0.3, p<0.01). In conclusion, our study indicates that UFE and UFF/UFE ratio are sensitive markers of 11beta-OHSD2, directly reflecting the activity of the renal isozyme and readily identifying patients with AME. The presence of an altered UFF/UFE ratio in both types of AME, although with different degree of severity, calls for re-evaluation and the classification of AME as a single disorder.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed2001

Laurdan fluorescence: a simple method to evaluate sperm plasma membrane alterations.

OBJECTIVE: To determine, by a simple fluorescence method, sperm plasma membrane alterations related with changes of lipid bilayer that, together with routine semen analysis, could help to elucidate the causes of the unexplained male infertility problems. DESIGN: Pilot study. SETTING: Andrology laboratory and biochemistry institute, medical school. PATIENT(S): Men whose semen was studied for infertility problems. INTERVENTIONS(S): No therapeutic intervention was performed on patients. MAIN OUTCOME MEASURE(S): Presence of spermatozoa plasma membrane alterations evidenced by evaluation of Laurdan fluorescence Generalized Polarization (GP) and reported as a function of increasing cell concentration, spermatozoa total motility, linear speed, and vitality. RESULT(S): Reporting GP values as a function of increasing sperm cell concentration, it is evident that the samples are distributed in two distinct areas: at >32 x 10(6) cells per milliliter, mean GP value was 0.303 +/- 0.015, whereas for lower sperm cell concentrations, the mean GP was 0.365 +/- 0.026 (P<.001). These data indicate that the spermatozoa plasma membranes are characterized by liquid-crystalline phases with different ordering degree and polarity and that about 50% of samples with normal semen characteristics (> or =20 x 10(6) cells per milliliter) show high GP values. CONCLUSION(S): Laurdan fluorescence can be used as a simple method to evaluate spermatozoa plasma membrane alterations, particularly in a group of infertile men presenting normal semen parameters. In these samples, Laurdan could be used as a simple tool for infertility assessment. In fact, it is known that compositional and physicochemical alterations of bilayer features can be important for the fertilizing ability of spermatozoa because they are necessary for a proper physiological membrane activity.

2-Naphthylamine↗
PubMed2001

Hypertension due to renal artery occlusion in a patient with antiphospholipid syndrome.

We report an unusual case of renovascular hypertension in a 16-year-old boy with primary antiphospholipid syndrome (PAPS), admitted to our clinic for severe drug-resistant hypertension and hypokalemia. Hormonal investigation revealed secondary aldosteronism and positive captopril test for renovascular disease. Aortography confirmed the occlusion of the left renal artery. After nephrectomy, normalization of blood pressure and secondary aldosteronism occurred. Presently the patient remains in good health, receiving warfarin anticoagulant therapy. PAPS is defined by the presence of antiphospholipid antibodies and recurrent thrombosis. Arterial thrombosis (29%) appears to be less prevalent than venous thrombosis. Thrombotic microangiopathy of the kidney is frequently observed but renal artery occlusion, as seen in our patient, is unusual.

Adolescent↗
PubMed2001

Decreased nitric oxide levels and increased calcium content in platelets of hypertensive patients.

Decreased levels of nitric oxide (NO) may contribute to impaired endothelium-dependent vasodilatation in essential hypertension. Moreover, in hypertension, major platelets aggregation and endothelial adhesion, and increased atherogenetic risks are also present. Nitric oxide produced by platelet NO synthase, which is similar to endothelial NO synthase, inhibits platelets aggregation by increasing cytoplasmic cyclic GMP levels and contributes in a major way to the antithrombogenic properties of endothelium. The aim of this study was to investigate platelet NO production and cytosolic Ca2+ levels in patients with essential hypertension and in healthy subjects. We studied NO production in 36 subjects (21 patients had essential hypertension and 15 subjects were normotensive); NO synthase activity was evaluated by measuring nitrite levels by the Griess reaction in the supernatant of sonicated platelets. Cytosolic Ca2+ levels were measured in intact platelets using the fluorescent probe Fura 2-AM. Nitric oxide levels in platelets were found higher in normotensive than in hypertensive patients (P < .0001). Nitric oxide levels in hypertensive women were significantly higher than in hypertensive men (P < .001). Hypertensive women and men had lower levels of nitrite than normotensive women and men (P < .001 and P < .002, respectively). Platelet cytosolic Ca2+ levels were higher in hypertensive patients than in normotensive subjects (P < .001). An inverse correlation was found between platelet cytosolic Ca2+ and NO levels (r = 0.74, P < .002). These data confirm the link between hypertension and altered platelets function and suggest a role for NO in cardiovascular events. Moreover, the higher levels of nitric oxide in child-bearing age women than in men further support the protective effect of estrogens on cardiovascular diseases.

Adult↗
PubMed2001

Variable expression of the transcription factors cAMP response element-binding protein and inducible cAMP early repressor in the normal adrenal cortex and in adrenocortical adenomas and carcinomas.

The molecular mechanisms leading to adrenocortical tumorigenesis have been only partially elucidated so far. Because the pituitary hormone ACTH, via activation of the cAMP pathway, regulates both cell proliferation/differentiation and steroid synthesis in the adrenal cortex, in this study we focused on the cAMP-dependent transcription factors cAMP responsive element modulator (CREM) and cAMP responsive element binding protein (CREB). We studied CREM and CREB expression by RT-PCR in human normal adrenal cortex (n = 3), adrenocortical adenomas (n = 8), and carcinomas (n = 8). We found transcripts corresponding to the isoforms alpha, beta, gamma, and tau2 of the CREM gene in all of the normal adrenal tissues, in the adenomas, and in seven of eight carcinomas. On the other hand, mRNA for the inducible cAMP early repressor isoforms, which derive from an internal promoter of CREM gene, was detected in the normal adrenal and in seven of eight adenomas, but in only three of eight carcinomas. Similarly, CREB transcripts were readily detectable in all normal adrenals and adenomas, whereas they were not found in four of eight adrenal carcinomas. To further characterize the carcinomas, telomerase activity and the expression of the ACTH receptor gene were determined. Telomerase activity in the carcinomas resulted in levels significantly higher than in the adenomas, whereas the levels of ACTH receptor mRNA were lower in the carcinomas. No correlation was found in the carcinomas between the levels of the ACTH receptor transcript and the loss of expression of CREB/inducible cAMP early repressor, suggesting that this alteration is not secondary to an upstream disregulation at the receptor level. In conclusion, our results suggest that an alteration in cAMP signaling may be associated with malignancies of the adrenal cortex.

Adenoma↗
PubMed2001

Body composition and metabolic features in women with adrenal incidentaloma or Cushing's syndrome.

The aim of this study was to evaluate body composition and metabolic features in women with nonhypersecretory adrenal cortical incidentaloma (AI) and women with Cushing's syndrome (CS) compared with healthy control (C) women matched for age, menopausal status, and body mass index. We examined 15 females with CS, 22 with AI, and 20 C. We evaluated anthropometric, hormonal, and metabolic parameters in all subjects. Body composition was measured by dual-energy x-ray absorptiometry for total body (TB); in addition, abdominal fat was measured between L2 and L4 vertebrae. Women with CS and AI were overweight; waist to hip ratio mean values showed that women with CS and AI had a central fat distribution. TB fat was significantly higher in CS than in C women, however, AI women also had high fat values. Abdominal fat was significantly more increased in CS than in AI and C women. Eighty percent of CS women and 50% of AI women were hypertensive. High density lipoprotein cholesterol levels were lower and triglyceride levels were higher in CS and AI women than in C. The area under the curve for glucose after oral glucose tolerance test was significantly higher in CS and AI than in C. AI had urinary free cortisol values slightly higher than C and than the normal range. In conclusion, these data indicate that AI are at an intermediate state between normal and pathological. These alterations suggest that a subtle cortisol hypersecretion is probably present in AI and it may be the factor promoting alterations of body composition and metabolic parameters.

Absorptiometry, Photon↗
PubMed2000

Adipose tissue as an endocrine organ? A review of some recent data.

Recent clinical and experimental data have radically modified the concept of adipose tissue as one solely devoted to energy storage and release. Adipose tissue is a target organ for glucocorticoids. Several studies of the function of the hypothalamic-pituitary-adrenal axis in obese subjects have failed to reach conclusive results. An innovative finding is that adipose tissue produces cortisol from its inactive precursor, cortisone. Identification of leptin, a hormone synthesised by adipose tissue, has ushered in the modern view that it is a true endocrine organ. Leptin is produced by subcutaneous and to a lesser extent by visceral adipose tissue. It has a central role in body weight and especially fat stores regulation, but is also involved in several complex functions, including the physiological processes associated with puberty. Angiotensinogen (AGT), another hormone synthesised in abundance by adipose tissue, is produced in larger amounts by visceral than subcutaneous fat. In addition, in man and animals adipose tissue appears to possess the whole renin-angiotensin system (RAS), suggesting that angiotensin II, the final effector of the system, is locally produced. The function of adipose RAS is not well known; besides participating, together with other hormones and substances, in adipocyte differentiation and fat tissue growth, it could be involved in the pathogenesis of the complications of obesity. All these findings have opened interesting prospects and are expected to yield further stimulating insights into the physiopathology of the adipose organ.

Adipose Tissue↗
PubMed2000

Laparoscopic adrenalectomy by the anterior transperitoneal approach: results of 108 operations in unselected cases.

BACKGROUND: The feasibility, safety, and results of 108 laparoscopic anterior transperitoneal adrenalectomies (six bilateral) were evaluated in a series of 105 patients. Three patients with a preoperative diagnosis of primary adrenal carcinoma were excluded from the study. METHODS: A total of 102 patients were included in the study based on exhaustive endocrinological and imaging assessment. Twenty-nine patients with nonsecreting adenoma, 34 with aldosterone-producing adenoma, 27 with cortisol-producing adenoma (five bilateral), 13 with pheochromocytoma (one bilateral), two with androgen-secreting adenoma, and three with metastases were considered eligible for adrenalectomy. Lesion size ranged from 3.5 to 12 cm. Concurrent surgical procedures were performed in 10 patients (9.8%). RESULTS: One (0.9%) intraoperative complication, a colon tear in a bilateral adrenalectomy, required conversion. There were two (1.9%) postoperative complications: one patient with thrombocytopenia developed hemoperitoneum and required a second laparoscopic procedure, and an intraabdominal abscess was treated medically. Mean postoperative hospital stay was 2.5 days (range, 1-7 days). Postoperative mortality was 0.9%; the patient with the colon tear died of sepsis 60 days after the operation. At a mean follow-up of 30 months (range, 1-62), normalization or improvement in hormone levels was observed in all patients with secreting adenomas, and significant improvement or cure was achieved in all patients with hypertension. CONCLUSION: Patients with secreting and nonsecreting adrenal lesions can be treated safety and effectively by laparoscopy with the anterior transperitoneal approach.

Adrenalectomy↗
PubMed2000

Management approaches to adrenal incidentalomas. A view from Ancona, Italy.

The definition of adrenal incidentaloma encompasses a heterogeneous spectrum of pathologic entities, including primary adrenocortical and medullary tumors, benign or malignant lesions, hormonally active or inactive lesions, metastases, and infections. This article provides an overview of the diagnostic clinical approach and management of the incidentally discovered adrenal masses. Approaches are based on data collected in more than 1000 cases of the Collaborative Study Group on Adrenal Incidentaloma of the Italian Society of Endocrinology and the authors' experience.

Adenoma↗
PubMed2000

Gene expression of angiotensinogen in adipose tissue of obese patients.

Recently, the genes of components of the renin-angiotensin system (RAS), namely angiotensinogen (AGT), angiotensin converting enzyme and angiotensin II receptor have been described in adipose tissue. In animal models the angiotensinogen in adipose tissue has been implicated in the pathogenesis of metabolic alterations and hypertension associated with obesity. The aim of our study was to evaluate the AGT gene expression both in visceral and subcutaneous adipose tissue in obese patients and lean subjects. AGT mRNA levels were measured by reverse transcriptase polymerase chain reaction (RT-PCR) using specific primers. AGT mRNA was expressed at variable levels in obese patients. It was significantly greater in visceral than in subcutaneous adipose tissue. Positive and significant correlation was found between the expression of AGT in visceral adipose tissue and BMI. These data suggest that angiotensinogen may be determinant of fat distribution and may be involved in the plurimetabolic syndrome of central obesity.

Adipose Tissue↗
PubMed2000

Effects of long-term treatment with human pure follicle-stimulating hormone on semen parameters and sperm-cell ultrastructure in idiopathic oligoteratoasthenozoospermia.

Ten subfertile men affected by idiopathic oligoteratoasthenozoospermia and exhibiting normal serum hormone levels received a long-term treatment with human pure follicle-stimulating hormone (hp-FSH) (150 IU, intramuscularly, three times per week for 6 months). Semen parameters and ultrastructural features of spermatozoa were evaluated before and after therapy. The results showed an increase in sperm cell concentration and, more interestingly, motility. Electron microscopic examination revealed an improved fine architectural pattern, mainly involving acrosome, head and chromatin and middle-piece, in accordance with the positive changes of functional data. No significant changes of hp-FSH treatment on serum hormone levels were observed, since the latter were found to be substantially unchanged after 6 months of therapy. The present data suggest: (i) the benefit of hp-FSH administration in idiopathic oligoteratoasthenozoospermia, when hormone parameters support a substantial integrity of spermatogenetic microenvironment and (ii) an optimal effect after long-term (6 months) therapy.

Adult↗