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Biomedical subjects

G B Melis

Publications and source records attributed to G B Melis.

At least 37 records · Page 2Linked to original sources
PubMed2001

Influence of melatonin administration on glucose tolerance and insulin sensitivity of postmenopausal women.

OBJECTIVE: The effect of melatonin on human carbohydrate metabolism is not yet clear. We investigated whether melatonin influences glucose tolerance and insulin sensitivity in aged women. PATIENTS: Twenty-two postmenopausal women of whom 14 were on hormone replacement therapy. DESIGN: After an overnight fast, at 0800 hours on two nonconsecutive days, placebo or melatonin (1 mg) were administered randomly and in a double blind fashion. Forty-five minutes later, an oral glucose tolerance test (75 g; OGTT) was performed in 13 women. In another nine women insulin-dependent (Si) and -independent (Sg) glucose utilization was tested by a frequently sampled intravenous glucose tolerance test (FSIGT). RESULTS: Areas under the response curve to OGTT (AUC) for glucose (1420 +/- 59 vs. 1250 +/- 55 mmol x min/l; P < 0.01), and C-peptide (42,0980 +/- 45,320 vs. 33,528 +/- 15,779 pmol x min/l; P < 0.02) were higher following melatonin than placebo, while Si values were lower (2.6 +/- 0.28 units vs. 3.49 +/- 0.4 units; P < 0.03). Si modifications induced by melatonin were inversely related to Si values of the placebo day (r(2) = 0.538; P < 0.025). CONCLUSIONS: The present results indicate that in aged women administration of 1 mg of melatonin reduces glucose tolerance and insulin sensitivity. The present data may have both physiological and clinical implications.

Analysis of Variance↗
PubMed2001

Evidence that cyproterone acetate improves psychological symptoms and enhances the activity of the dopaminergic system in postmenopause.

The psychological symptoms assessed with a validated psychometric scale, SCL-90, were significantly higher in postmenopausal women (PMW; 60 subjects) than in premenopausal women (20 subjects). In the same PMW, the activity of the dopaminergic system, assessed with the PRL response to the dopamine-blocking agent sulpiride, was significantly lower than that in premenopausal women. During a period of 12 weeks the 60 PMW were randomly divided into 3 groups: no treatment (group A; n = 20), treatment with estradiol (E(2)) alone (patches with a E(2) release of 50 microg/24 h; group B; n = 20), and treatment with hormonal replacement therapy [estradiol valerate (EV) at a daily dose of 2 mg for 11 days and EV at the same daily doses plus cyproterone acetate (CPA) at a daily dose of 1 mg/day for 10 days; group C; n = 20). At the 12th week of the observation, only in group C women were the psychological symptoms significantly decreased, and the indirect evaluation of the dopaminergic system activity through PRL response to sulpiride showed a significant increase. During the same period, no changes in testosterone levels were observed in any group of PMW, whereas a significant increase in E(2) levels was found in both groups B and C. Although it is likely that the improvement in psychological symptoms with EV and CPA was due to progestin, we cannot rule out the possibility that greater estrogen exposure may have played a role.

Adult↗
PubMed2000

Evidence of a role of endogenous estrogen in the modulation of autonomic nervous system.

We studied heart rate variability in 14 healthy women before and after oophorectomy compared with 14 matched women who underwent hysterectomy with ovarian conservation. Surgical menopause induced a decline in cardiac vagal modulation with a shift toward sympathetic hyperactivity. Recovery of the baseline condition after 3 months of estrogen replacement therapy in oophorectomized women suggests a role of estrogen in the autonomic nervous control of the cardiovascular system.

Cardiovascular System↗
PubMed2000

A case of dermatofibrosarcoma protuberans of the vulva with a COL1A1/PDGFB fusion identical to a case of giant cell fibroblastoma.

Dermatofibrosarcoma protuberans (DFSP) is a highly recurrent low-grade soft tissue sarcoma, which is usually located on the trunk. Presentation in the vulva is rare, with only 13 cases being reported to date, none of which have been investigated at the cytogenetic or molecular level. Specific cytogenetic abnormalities, involving chromosomes 17 and 22, are characteristic features of DFSP and giant cell fibroblastoma (GCF), a tumor closely related to DFSP. These chromosomal rearrangements result in the fusion of the COL1A1 and PDGFB genes in both lesions and show wide variation in the position of the fusion point in COL1A1. Here, we describe a case of DFSP of the vulva with a typical monotonous storiform pattern, with no foci of multinucleated giant cells. Cytogenetic analysis showed a 47,XX,+r karyotype in 50% of the cells, and molecular investigation disclosed the presence of a transcript fusing COL1A1 exon 37 to PDGFB exon 2. This is the first case of DFSP showing such a fusion point, which is intriguingly identical to that found in a GCF case, indicating that the COL1A1/PDGFB fusion point position does not seem to affect tumor morphology. This finding further underlines the very close relationship between these two morphologically distinct entities.

Adult↗
PubMed2000

Evidence that treatment with monophasic oral contraceptive formulations containing ethinylestradiol plus gestodene reduces bone resorption in young women.

The aim of the study was to evaluate if a pill containing the same dose of the same type of progestin compound (gestodene, GES, 75 microg) but different doses of ethinylestradiol (EE2) (20 or 30 microg) differently influences specific markers of bone resorption (urinary levels of pyridinoline (PYR) and dexoxypyridinoline (D-PYR)). During the 12 months of the study a significant decrease of urinary levels of PYR and D-PYR was found in 2 groups of young post-adolescent women taking the pills with 20 and 30 microg of EE2 in comparison with control women (subjects of the same age group with normal menstrual cycle who did not use contraception). In women taking pills with 20 or 30 microg EE2, the levels of sex hormone-binding globulin (SHBG) significantly increased during treatment in comparison with baseline, whereas in the same time period no changes occurred in control women. These findings suggest that similar to the pill containing 30 microg EE2, the lower dosage of the EE2 pill (20 microg) is also capable of reducing bone resorption. Twenty and 30 microg EE2 pills exert the same biological estrogenic effect. In fact, SHBG levels significantly increased with both pills. However, an additional effect of the progestin compound that could act directly on progestin or estrogen receptors of bone cannot be excluded. Since contraception with a pill containing the lowest estrogen dose is associated with the lowest incidence of side effects, these findings further suggest a pill containing 20 microg EE2 for young post-adolescent women would be the best choice.

Adult↗
PubMed2000

Different circulatory response to melatonin in postmenopausal women without and with hormone replacement therapy.

In young men and women, melatonin influences vascular reactivity and reduces blood pressure and norepinephrine levels. Herein, we investigated whether these effects are conserved in postmenopausal women without and with hormone replacement therapy (HRT). Oral melatonin (1 mg) or placebo was randomly and in double blind fashion administered to 18 untreated and 13 postmenopausal women who were treated continuously with transdermal estradiol (50 microg/day) plus cyclic medroxyprogesterone acetate (5 mg/day x 12 days every 28 days). Internal carotid artery pulsatility index (PI), an index of downstream resistance to blood flow, blood pressure and catecholamine levels were evaluated. In untreated postmenopausal women, melatonin was ineffective, while in HRT-treated women, studied during the only estrogenic phase, melatonin reduced, within 90 min, systolic (-8.1 +/- 9.9 mmHg; P = 0.054), diastolic (-5.0 +/- 7.0 mmHg; P = 0.049) and mean (- 6.0 +/- 6.6 mmHg; P = 0.037) blood pressure. Norepinephrine (-50.1 +/- 66.7 pg/mL; P = 0.019), but not epinephrine levels, were also significantly reduced. Similarly, resistance to blood flow in the internal carotid artery, as evaluated by the PI, decreased (-0.190 +/- 0.15; P = 0.0006) in a way that was linearly related to pre-existing PI values (r2 = 0.5; P = 0.0059). These data show that the circulatory response to melatonin is conserved in postmenopausal women on HRT but not in untreated postmenopausal women. Possible physiological and pharmacological implications of these data on the cardiovascular risk of postmenopausal women can be envisioned.

Antioxidants↗
PubMed2000

Transvaginal ultrasonography associated with colour Doppler energy in the diagnosis of hydrosalpinx.

The aims of this prospective study were to investigate the accuracy of B-mode transvaginal ultrasonography alone, using the typical finding of the presence of an elongated shaped mass with incomplete septa, in the screening of hydrosalpinx in women undergoing surgery for gynaecological diseases, and to determine the predictive value of this method combined with colour Doppler energy (CDE) imaging evaluation and CA125 concentrations in differentiating hydrosalpinx from other adnexal masses. In the first part of the study, 378 consecutive pre-menopausal non-pregnant women were submitted to transvaginal ultrasonography alone before surgery. In the second part of the study, 256 adnexal masses underwent transvaginal ultrasonography combined with CDE imaging evaluation associated with spectral Doppler analysis and plasma concentrations of CA125. Sensitivity and specificity for the ultrasonographic screening were 84.6 and 99.7% respectively, calculated for each adnexum (n = 756) and 93.3 and 99.6% respectively, calculated for each mass, for differentiating hydrosalpinx from other adnexal masses. The CDE imaging and the evaluation of CA125 plasma concentrations do not seem to increase the accuracy of B-mode transvaginal ultrasonography. Inter- and intra-observer agreement, expressed in terms of k-values, was high (0.87 and 0.93 respectively). In conclusion, transvaginal ultrasonography alone is a useful method of detection of hydrosalpinx.

Adnexal Diseases↗
PubMed2000

Oral use of interferon therapy in cervical human papillomavirus infection.

The efficacy and the optimal dose of systemic alpha-interferon treatment of genital human papillomavirus infection is now under discussion because of high cost, low compliance and systemic toxicity of this drug. Recent studies seem to suggest that natural alpha-interferon may also have antiviral efficacy in humans after oral administration of low doses of the drug. For this reason, the efficacy and side-effects of an oral preparation of natural alpha-Interferon (OROFERONE-IFI) have been evaluated in a randomized, placebo controlled trial. We report here the results of this preliminary study. Low doses (150U tid for 8 weeks) of the drug were administered to 12 patients with mild cervical dysplasia and human papillomavirus infection. A significantly higher proportion of Interferon treated subjects showed a colposcopic and histological regression of the lesion after months of treatment in comparison with 9 placebo treated patients (75% vs 30%) without major side effects. These results seem to justify wider evaluations of this approach to Interferon treatment characterized by lower costs and fewer side effects in comparison with traditional systemic high dose treatment of alpha Interferon.

Administration, Oral↗
PubMed2000

[Role of pH as a regulator of vaginal physiological environment].

In the vagina there are several microorganisms. Their survival is fundamental to have a physiological environment in the vagina (ecosystem). The same vaginal environment playg a fundamental role to guarantee tho survival of resident microorganisms. Several factors, like changes of temperature and oxygenation, can interfere on vaginal ecosystem, but the resident vaginal microorganisms are the main factors to stabilize the vaginal ecosystem. The Doderlein's lactobacillus is the predominant vaginal microorganism. It is capable of fermenting the glycogen deriving from the decline of the eutrophic vaginal mmucosa, to lactic acid with release of hydrogen ions. The final result of that metabolism is an acid pH with values between 4-4.5. Vaginal pH undergoes physiologically changes from birth to menopause, according to changes of ovarian steroids occurring during woman's life. Adequate levels of estrogens play a fundamental role in the trophism of vaginal mucosa. In fact, estrogens increase the cellular content of glycogen. Exogenous acbvities on vaginal pH can be exerted by several factors, such as sexual activily, oral contraceptives, systemic diseases, vaginal infections (candidosis, thrichomonias, vaginosis), systemic or local therapies. They incrcase vaginal pH by acting through different mechanisms. The increase of vaginal pH is detrimental for the survival of Doderlein's lactobacillus, but not for the pathogenetic microorganisms whose replication, on the contrary, is favored by the absence of contraction exerted by Doderlein's bacillus. It has been showed that local acidifying substances (lactic acid, lactobacillus and substances recently synthesized like alpha-aminovalerianic acid, policarbophil and carbopol 934) are useful in restoring the biological and chemical characteristics of the vaginal ecosystem.

Animals↗
PubMed1999

Effects of acute administration of natural progesterone on peripheral vascular responsiveness in healthy postmenopausal women.

Peripheral vascular responses to acute administration of natural progesterone were studied in 12 postmenopausal women (mean +/- SD age 50.3 +/- 4.8 years) with no evidence of cardiovascular disease. According to a randomized, double-blind protocol, all subjects were given natural progesterone as a vaginal cream, able to produce a rapid peak and decay of plasma hormone concentrations, or matched placebo, with crossover after a 1-week washout period. Forearm blood flow and peak flow after ischemic stress (ml/100 ml/min), local vascular resistance (mm Hg/ml/100 ml/min), venous volume (ml/100 ml), and venous compliance (ml/100 ml/mm Hg) were measured by strain-gauge venous occlusion plethysmography at baseline and after progesterone or placebo administration. Plasma norepinephrine concentrations were determined by high-performance liquid chromatography with electrochemical detection. Progesterone sharply decreased forearm blood flow (p <0.01) through an increase in local vascular resistance (p <0.01). Measures of venous function remained unchanged. Although the hormone increased circulating norepinephrine concentrations (p <0.05), there were no significant changes in mean arterial pressure or heart rate. Furthermore, progesterone reduced the local vasodilator capacity, shown by a decrease in forearm delta flow (difference between peak flow and basal flow, p <0.05). Compared with the well-known effect of estrogen, progesterone exerted an opposite action on peripheral vascular responsiveness. Peripheral circulatory changes may be attributed to a direct activity of progesterone on the arterial wall and may in part reflect a modulation of the hormone on peripheral sympathetic tone. Consideration must be given to the hypothesis that the addition of progestin may attenuate the beneficial effects of unopposed estrogen replacement therapy in postmenopausal women.

Cardiovascular Physiological Phenomena↗
PubMed1999

Study of myocardial contractility by pulsed wave Doppler tissue imaging does not reveal an inotropic effect of estrogen at physiologic dose.

We studied myocardial contractility by pulsed wave Doppler tissue imaging in 6 postmenopausal healthy women. According to a crossover, double-blind protocol, we randomized patients to treatment with transdermal patches of estradiol-17beta or matched placebo. Estradiol-17beta did not modify local systolic and diastolic functions. Thus, at least when acutely administered, estrogen seems to be unable to determine hemodynamic changes at the myocardial level, in opposition to what occurs in the peripheral vascular system.

Administration, Cutaneous↗
PubMed1999

Effects of melatonin on vascular reactivity, catecholamine levels, and blood pressure in healthy men.

In this study it was investigated whether the oral administration of melatonin (1 mg) in comparison to placebo was able to reduce blood pressure, vascular reactivity, and catecholamines in men, as previously reported in young women. The administration of melatonin significantly reduced blood pressure, the pulsatility index in the internal carotid artery, and catecholamines levels within 90 minutes. The effect of melatonin on the artery pulsatility index was related to baseline values, being greater in men with higher baseline values. The present data indicate that melatonin may blunt the activity of the cardiovascular system and may have both physiopathologic and clinical implications.

Adult↗
PubMed1999

Effect of chronic administration of cabergoline on uterine perfusion in women with polycystic ovary syndrome.

OBJECTIVE: To confirm whether patients with polycystic ovary syndrome (PCOS) have a reduction in uterine perfusion and to verify whether chronic administration of cabergoline can decrease this high vascular resistance. DESIGN: Prospective randomized trial. SETTING: Endocrinological Centre of the Department of Obstetrics and Gynecology, University of Cagliari, Cagliari, Italy. PATIENT(S): Thirty patients were enrolled in the study: 20 affected by PCOS and 10 healthy controls. Patients with PCOS were randomly assigned to one of two treatments for 3 months: oral administration of cabergoline (0.5 mg) every week or oral administration of placebo every week. INTERVENTION(S): All patients underwent transvaginal ultrasonography associated with Doppler flow measurement of the uterine artery, and serum hormone concentrations were determined during the early follicular phase. In women with PCOS, Doppler flow measurement and hormonal assessment were repeated in the early follicular phase of the third month of treatment. MAIN OUTCOME MEASURE(S): Pulsatility index of the uterine artery before and during treatment. RESULT(S): The mean pulsatility index of the uterine artery in patients with PCOS was significantly higher than that of the control group (3.29+/-0.5 and 2.01+/-0.2, respectively). Patients with PCOS treated with cabergoline showed a significant increase in uterine perfusion, with a pulsatility index of 3.14+/-0.6 before and 2.39+/-0.5 during the treatment. No difference was found in patients with PCOS treated with placebo. CONCLUSION(S): Patients with PCOS have high resistance in the uterine arteries, but chronic administration of cabergoline can increase uterine perfusion.

Administration, Oral↗
PubMed1999

Treatment with flutamide improves hyperinsulinemia in women with idiopathic hirsutism.

OBJECTIVE: To investigate insulin metabolism and its modifications induced by the administration of flutamide, a specific antiandrogen compound, in women with idiopathic hirsutism (IH) and in nonobese women with polycystic ovary syndrome (PCOS). DESIGN: Prospective, randomized trial. SETTING: Endocrinological Centre of the Department of Obstetrics and Gynecology, University of Caligari, Caligari, Italy. PATIENT(S): Thirty-two women with normal body mass index participated in the study: 11 with clinical and hormonal features of PCOS and 21 age- and weight-matched normally cycling women with IH (n = 11) and without IH (n = 10, controls). INTERVENTION(S): Each subject with PCOS or IH was assigned randomly to receive either flutamide tablets (250 mg twice a day) or placebo for > or =5 months. Twelve subjects (6 with PCOS, 6 with IH) received flutamide and 10 (5 with PCOS, 5 with IH) received placebo. All subjects ingested 75 g of glucose and then underwent an oral glucose tolerance test (OGTT), 3-7 days after spontaneous or medroxyprogesterone acetate (5 mg daily for 5 days)-induced menses. In women with PCOS or IH, the OGTT was repeated at the fourth month of treatment. MAIN OUTCOME MEASURE(S): Fasting and OGTT-stimulated levels of glucose, insulin, and C peptide. RESULT(S): Both fasting and OGTT-stimulated levels of insulin and C peptide were significantly higher in women with PCOS and in those with IH than in controls. Placebo did not modify parameters of glucose metabolism. Flutamide was capable of significantly blunting fasting and OGTT-stimulated secretion of insulin only in women with IH. CONCLUSION(S): Hyperinsulinemia exists in women with IH as well as in nonobese women with PCOS. Treatment with flutamide can completely reverse hyperinsulinemia only in women with IH, which suggests that the efficacy of the drug is dependent on peripheral androgen hyperactivity.

Adult↗
PubMed1999

Effect of ovarian suppression on glucose metabolism of young lean women with and without ovarian hyperandrogenism.

Gonadal steroids are believed to influence glucose metabolism, oestrogens inducing an improvement and androgens or progestins a deterioration. At baseline and after 3 months of ovarian suppression with a gonadotrophin-releasing hormone analogue (GnRHa: goserelin depot 3.75 mg/28 days), glucose metabolism was evaluated in eight lean women affected by ovarian hyperandrogenism (PCOS) and six age-weight-matched non-hyperandrogenic women (controls) by using both an oral glucose tolerance test (75 g; OGTT) and the minimal model method. The latter method allows calculation of peripheral insulin sensitivity (Si) and glucose dependent glucose utilization (Sg). In PCOS, higher fasting concentrations (P < 0.05) of insulin and C-peptide, and lower Sg (P < 0.05) and Si (P < 0.01) were found. GnRHa did not significantly modify glucose metabolism of controls, while in women with PCOS it decreased fasting glucose (P < 0.05) and significantly increased Si (P < 0.03) up to control values. The present data indicate that strong suppression of ovarian activity improves Si in lean women with PCOS, while it is without relevant effects on glucose metabolism of non-hyperandrogenic women.

Adult↗
PubMed1999

Oral contraceptives and vascular reactivity of great vessels in women.

Blood pressure and great vessel vascular reactivity, evaluated by color Doppler ultrasound, were investigated in users of third-generation oral contraceptives (n = 18) compared to non-users, who were studied either in the follicular (n = 8) or in the luteal (n = 10) phase of the menstrual cycle. Blood pressure measured at rest in the supine position, evaluated both in the follicular phase and in the luteal phase, was similar between oral contraceptive users and non-users. The pulsatility index (an indirect index of resistance to blood flow) of both the internal carotid artery and the axillary artery was similar in control women studied in the follicular phase and in the luteal phase. By contrast, in users of oral contraceptives, pulsatility index values of the internal carotid artery tended to be higher, whilst those of the axillary artery were significantly higher, than those of women in either the follicular phase (p < 0.01) or the luteal phase (p < 0.025). In conclusion, new third-generation oral contraceptives do not have a significant impact on blood pressure control, but still tend to increase vascular resistance to blood flow, particularly in areas more involved in the regulation of blood pressure, for example the axillary artery.

Adult↗
PubMed1999

Effect of multiple follicular development on uterine perfusion in subsequent spontaneous cycles.

OBJECTIVE: To investigate the effect of ovarian hyperstimulation on uterine perfusion during a subsequent natural cycle to evaluate if there is a long-term effect of treatment with gonadotropins. STUDY DESIGN: Thirty-five infertile couples were subjected to three cycles of multiple follicular development. Uterine blood flow was determined during the follicular phase, ovulation and luteal phase of the spontaneous cycle preceding and the one following the stimulated cycles. RESULTS: No significant difference was present among pulsatility index (PI) values in the two cycles. PI values (+/- SD) were 2.05 +/- 0.5, 2.28 +/- 0.4, 2.18 +/- 0.5, 2.13 +/- 0.4 and 2.00 +/- 0.5, respectively, in the pretreatment cycle and 2.32 +/- 0.5, 2.56 +/- 0.6, 2.42 +/- 0.3, 2.37 +/- 0.4 and 2.29 +/- 0.5, respectively, in the posttreatment cycle. An inverse correlation was found between PI values and estradiol in the follicular phase of the first spontaneous cycle. As for radial and subendometrial arteries, no significant difference was present for PI values in the two cycles. CONCLUSION: Multiple follicular development seems not to have a long-term effect on uterine perfusion in the subsequent spontaneous cycle.

Adult↗