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Biomedical subjects

A Volpe

Publications and source records attributed to A Volpe.

At least 127 records · Page 7Linked to original sources
PubMed1997

Cardiovascular response to cognitive stress in subjects with menstrually related disorders.

We measured reactivity to a stress paradigm during the premenstrual period in 19 women affected by Menstrually Related Disorders (MRD) and in 11 normal controls. Eight had premenstrual syndrome diagnosed by the Menstrual Distress Questionnaire and 11 suffered menstrual migraine, diagnosed according to International Headache Society criteria. Subjects were observed during two menstrual cycles and submitted to a psychocognitive test (Stroop Color Word) during the luteal phase. In both groups the stimulation by Stroop C-W was present for systolic blood pressure (SBP) (F = 18.14, p = 0.000), diastolic blood pressure (DBP) (F = 9.56, p = 0.000), and heart rate (F = 12.80, p = 0.000). Moreover, an interaction of response by group was present for DBP (2.58, p = 0.04); DBP values were higher in MRD subjects. Also baseline DBP values were higher in MRD with respect to controls. Area under the curve (AUC) subtracted from baseline for the SBP, DBP and heart rate did not differ between groups. In conclusion, MRD subjects facing a cognitive stress had normal cardiovascular response. However, patients had increased arousal of cardiovascular measures before and after testing. The significant differences during stress of testing were dissociated from those of experimental stress stimulation. MRD subjects may have less ability to cope with novelty than healthy volunteers.

Adult↗
PubMed1997

Homeostatic versus circadian effects of melatonin on core body temperature in humans.

Evidence obtained in animals has suggested a link of the pineal gland and its hormone melatonin with the regulation of core body temperature (CBT). Depending on the species considered, melatonin intervenes in generating seasonal rhythms of daily torpor and hibernation, in heat stress tolerance, and in setting the CBT set point. In humans, the circadian rhythms of melatonin is strictly associated with that of CBT, the nocturnal decline of CBT being inversely related to the rise of melatonin. Whereas there is inconsistent evidence for the suggestion that the decline of CBT may prompt the release of melatonin, conversely, stringent data indicate that melatonin decreases CBT. Administration of melatonin during the day, when it is not normally secreted, decreases CBT by about 0.3 to 0.4 degree C, and suppression of melatonin at night enhances CBT by about the same magnitude. Accordingly, the nocturnal rise of melatonin contributes to the circadian amplitude of CBT. The mechanisms through which melatonin decreases CBT are unclear. It is known that melatonin enhances heat loss, but a reduction of heat production cannot be excluded. Besides actions on peripheral vessels aimed to favor heat loss, it is likely that the effect of melatonin to reduce CBT is exerted mainly in the hypothalamus, where thermoregulatory centers are located. Recent observations have shown that the acute thermoregulatory effects induced by melatonin and bright light are independent of their circadian phase-shifting effects. The effect of melatonin ultimately brings a saving of energy and is reduced in at least two physiological situations: aging and the luteal menstrual phase. In both conditions, melatonin does not exert its CBT-lowering effects. Whereas in older women this effect may represent an age-related alteration, in the luteal phase this modification may represent a mechanism of keeping CBT higher at night to promote a better embryo implantation and survival.

Body Temperature↗
PubMed1997

Changes of dimeric inhibin B levels in maternal serum throughout healthy gestation and in women with gestational diseases.

Human placenta expresses subunit messenger RNAs for synthesizing inhibin A and B. Experimental studies have shown an effect of inhibins on placental hormone secretion, but an endocrine function is suggested by the high levels in maternal circulation. Although information is available on the changes of inhibin A in serum of healthy pregnant women, data on inhibin B levels are limited to early gestation. The aim of the present study was to investigate the changes of inhibin B levels in maternal circulation in healthy pregnant women throughout gestation, and to evaluate whether early pregnancy disturbances or gestational diseases are characterized by abnormal inhibin B levels. The protocol included various groups of pregnant women. A longitudinal evaluation of serum inhibin B levels was done at specific intervals (8-12, 13-18, 19-24, 25-28, 29-33, and 34-40 weeks) in the following groups: 1) healthy pregnant women (n = 13); 2) women at risk of hypertension who did not develop hypertension (n = 8); and 3) women with chronic hypertension (n = 13). In women in group 1, a blood sample was also obtained in the postpartum period (12, 24, and 48 h after delivery). Other pregnant women with abnormal bleeding in the first trimester were studied; they were subdivided into women with ongoing pregnancy (n = 12); and women with miscarriage (n = 22); a control group of healthy pregnant women at the same gestational age was also included (n = 18). A final group of women with gestational diseases (n = 34) was included in the study and included women with: 1) pregnancy-induced hypertension (n = 10); 2) preeclampsia (n = 17); and 3) intrauterine fetal growth retardation (n = 7). A group of healthy nonpregnant women (n = 9) was used as controls, and a blood specimen was collected during both the early- to midfollicular and midluteal phases of the menstrual cycle. Serum dimeric inhibin B levels were measured by using a double-antibody enzyme-linked immunoadsorbent assay. Early gestation inhibin B levels were similar to those of nonpregnant controls and showed a significant rise during the third trimester (P < 0.01). The highest maternal serum inhibin B levels were found at term (P < 0.01). Values significantly returned to control levels within 12-48 h (P < 0.01) after placental delivery. Women at risk of hypertension showed a similar gestational-related increase of inhibin B levels during the third trimester, without any significant difference when compared with healthy women. Women with chronic hypertension showed significantly lower levels at term (P < 0.01). Women with pregnancy-induced hypertension or preeclampsia, or who were carrying a fetus with intrauterine growth retardation showed serum inhibin B levels during the third trimester of gestation consistently lower than in control healthy women at the same gestational age (P < 0.001, mean +/- SEM). Maternal serum inhibin B levels in women with early pregnancy bleeding or miscarriage were similar to those of healthy pregnant women at the same gestational age, independent from the outcome of gestation. The present study showed that maternal serum inhibin B levels increase in the last trimester of normal pregnancy, with low levels in women with hypertensive disturbances or intrauterine growth retardation.

Adult↗
PubMed1997

Color Doppler analysis in oligo- and amenorrheic women with polycystic ovary syndrome.

The objective of this study was to determine whether amenorrheic women have more severe blood flow variations and clinical-endocrinological patterns in comparison with oligomenorrheic polycystic ovary syndrome (PCOS) patients. Twenty oligomenorrheic women (cycle length > 35 days; Group I), and 20 amenorrheic women (no vaginal bleeding for at least 6 months; Group II) were submitted to ultrasonographic evaluation of ovarian volume, follicle distribution, number and diameter, color Doppler analysis of uterine and intraovarian blood flow, hormonal assay of different compartments, and plasma evaluation of lipid profile. The number of subcapsular small-sized follicles, and the ovarian volume, androstenedione and luteinizing hormone (LH) plasma levels, and the LH/follicle-stimulating hormone (FSH) ratio were significantly higher in the amenorrheic group compared with the oligomenorrheic patients. Furthermore, significantly lower high-density lipoprotein (HDL) and HDL/total cholesterol ratio were observed in Group II compared with Group I. In addition, in Group II, higher resistance in the uterine arteries and lower impedance to blood flow in the intraovarian arteries have been shown. The assessment of ovarian morphology by transvaginal ultrasound and Doppler flow analysis of both intraovarian and uterine arteries in patients with PCOS may provide an insight into the pathological state and the degree of progression of the disease.

Adult↗
PubMed1997

Oral contraceptives and bone metabolism.

In women, the bone metabolism is markedly influenced by gonadal steroids and by their fluctuations. Indeed, estrogens influence bone metabolism by influencing endocrine and paracrine functions involved in bone remodelling. In normally cycling women, the administration of oral contraceptives does not increase bone mineral density and does not induce deleterious effects on bone. In women with ovulatory disturbances, bone turnover is increased and bone mineral density is lower than in normally cycling women. In these cases, administration of oral contraceptives is capable of blocking increased bone loss and of restoring a normal bone mineral density. Similarly, in women treated with gonadotropin releasing hormone (GnRH) analogs, the concomitant administration of oral contraceptives completely antagonizes GnRH analog-induced bone loss. The progestogenic component of oral contraceptives seems to contribute to the protective effect of estrogens on bone. Oral contraceptives are safe for bone maintenance in normal adult women, and are indeed indicated to prevent postmenopausal osteoporosis in women with ovulatory disturbances.

Adolescent↗
PubMed1997

Biochemical aspects of hormonal contraception: effects on bone metabolism.

Both trabecular and cortical bone mineral content reduction physiologically occur during the premenopausal period and, overall, at the time of menopause. It is related to plasma estrogen fall. Several studies have examined the relationship between bone density and oral contraceptives (OCs), but their results disagree. The different results may be due to the small number of patients investigated, the different OC formulations, and to the multifactorial nature of the bone loss phenomenon. Furthermore, the use of different techniques and different sites for measuring the bone density may limit the interpretation and reproducibility of the reported findings. Our previous studies evidenced that: (1) in premenopausal (40-45 years) women (n = 26), OCs, over a period of 2 years, do not induce any change either in bone mineral density or in bone metabolism biochemical markers (osteocalcin, alkaline phosphatase, urinary hydroxyproline/creatinine ratio; and (2) independent from the therapy length, the premenopausal use of OCs does not modify the bone mineral loss in postmenopausal patients (n = 40). The present study compared, over a period of 36 months, in perimenopausal (46-53 years; follicle stimulating hormone < or = 35 mU/ml; estradiol < 50 pg/ml) women, the effect of OCs (n = 8) on bone metabolism. The results were compared with those of a matched control group (n = 9). In the treated group, a slight, though not significant, bone mass improvement was observed during the entire therapy period, whereas, in the control group, a continued and progressive bone mass loss was observed and a significant decrease was shown at the end of the observational period. Our data suggest that OCs have no significant effects on bone metabolism in women during their childbearing years. However, OCs may be beneficial in inhibiting bone reabsorption in pre- and postmenopause. Furthermore, the pill, also in virtue of its contraceptive effect, would be the first presidium in hormone therapy in the premenopause.

Alkaline Phosphatase↗
PubMed1997

Starvation increases the number of coliform bacteria in the caecum and induces bacterial adherence to caecal epithelium in rats.

OBJECTIVE: To investigate the impact of starvation for 24 and 48 h on the number of coliform bacteria in the caecal contents, on the mucosal adherence of coliform bacteria, and on bacterial translocation in rats. DESIGN: Open prospective study. SETTING: University departments of surgery and microbiology, Sweden. MATERIAL: 46 adult male Sprague-Dawley rats. INTERVENTIONS: 19 rats served as controls, and were fed until samples were taken. Six animals were starved for 24 h and another 15 for 48 h, with free access to water, and then anaesthetised before blood, mesenteric lymph nodes (MLN), caecum, and caecal contents were sampled. To verify bacterial translocation in this strain of rats, another six rats underwent controlled haemorrhage for 60 min to reduce the blood pressure to 55 mm Hg mean arterial pressure (MAP). These rats had free access to food and water before haemorrhage but were allowed only water until samples were taken 24 h after haemorrhage. MAIN OUTCOME MEASURES: Presence and number of coliform bacteria in samples taken from caecal contents, caecal epithelium, MLN, and blood. RESULTS: Starvation for 24 h increased the number of coliform bacteria (colony forming units (CFU)/g) in the caecal contents 25-fold (p < 0.05). Starvation for 48 h further increased the number by a factor of 100. The number of coliform bacteria that adhered to the caecal epithelium increased 3,000 times in rats that had been starved for 48 h (p < 0.001). There was no significant difference in translocation (as indicated by cultures from MLN) between rats that had been fed and those that had been starved for 48 h. In 4 of the 6 rats that were bled and then starved for 24 h there were signs of bacterial translocation, which was significantly more than the 1/19 in fed rats (p < 0.05). CONCLUSION: Starvation increases the number of bacteria in the caecal contents and increases bacterial adherence to the caecal epithelium. These changes may contribute to the previously reported increase in bacterial translocation in starved compared wit fed rats that were subjected to stress. The same changes in the gut were observed in animals subjected to haemorrhagic stress in addition to starvation, and in which bacterial translocation was evident.

Animals↗
PubMed1996

Salmon calcitonin plus intravaginal estriol: an effective treatment for the menopause.

OBJECTIVE: Intravaginal estriol (E3) effectively improves postmenopausal genito-urinary disturbances, without stimulating endometrial proliferation. The aim of the present study was to evaluate the effect of intravaginal estriol (E3) plus nasal spray salmon calcitonin (sCT), to improve neurovegetative symptoms and to prevent the decline of bone mineral density (BMD) of postmenopausal women. METHODS: Two hundred and fourteen (214) healthy postmenopausal women were treated for 12 months with: (1) E3 (0.5 mg every other day) + Ca (0.5 g/day); (2) E3 + Ca + sCT (50 IU x 2/day); (3) sCT + Ca; (4) Ca. Climacteric complaints, such as hot flushes and sweating, BMD at the distal 1/10 of the radius, analyzed by dual photon absorptiometry, urinary excretion of hydroxyproline and serum alkaline phosphatase were evaluated at baseline and every 6 months. At the same time, patient compliance and drug tolerability were evaluated. RESULTS: E3 but not sCT, improved hot flushes and sweating. E3 blunted but not completely counteracted the BMD decline observed in women treated with only Ca, and reduced urinary hydroxyproline excretion. sCT markedly increased BMD values and reduced both urinary hydroxyproline excretion and serum alkaline phosphatase. These effects were not potentiated by E3 coadministration. All treatments were well tolerated. CONCLUSIONS: Present data indicate that the combined administration of intravaginal E3 and sCT may represent an alternative therapeutic regimen for those postmenopausal women who do not accept or have contraindications to classical hormone replacement therapy.

Absorptiometry, Photon↗
PubMed1996

Color Doppler hysterosalpingography in the diagnosis of tubal patency.

OBJECTIVE: To assess tubal patency by color Doppler hysterosalpingography (HSG). DESIGN: Comparative study of color Doppler HSG with roentgenogram HSG and chromolaparoscopy in infertile women of childbearing age. SETTING: Clinical environment. PATIENTS: Sixty female patients (22 to 39 years) with long-lasting infertility problems. INTERVENTION: Sterile saline was transcervically injected into the uterine cavity through a catheter and color Doppler HSG was performed. All the patients were submitted to roentgenogram HSG and chromolaparoscopy. MAIN OUTCOME MEASURES: The diagnostic efficacy of color Doppler HSG and its concordance with "gold standard" chromolaparoscopy were analyzed. RESULTS: Correlation between color Doppler HSG and roentgenogram HSG with chromolaparoscopy occurred in 86% versus 93% of all women studied. CONCLUSIONS: Color Doppler HSG with its accuracy and safety results a promising alternative technique to roentgenogram HSG in diagnosing tubal status in infertile patients.

Adult↗
PubMed1996

Color Doppler analysis in lean and obese women with polycystic ovary syndrome.

The objective of this study was to determine whether obese patients with polycystic ovary syndrome (PCOS) show different ovarian and uterine blood flow patterns in comparison with lean patients. Sixteen obese (body mass index: BMI = 31.4 +/- 3.6 kg/m2) and 22 lean (BMI = 21.1 +/- 1.3 kg/m2) PCOS patients underwent, in the early follicular phase if oligomenorrheic or randomly if amenorrheic, ultrasonographic evaluation of ovarian volume, echodensity and follicle number; transvaginal color Doppler evaluation of uterine and intraovarian blood flow; and radioimmunological assay of luteinizing hormone, follicle stimulating hormone, growth hormone, estradiol, progesterone, testosterone, androstenedione, insulin, insulin-like growth factor I, and other hormonal parameters. Hematocrit, plasma glucose, total cholesterol, high density lipoprotein and triglycerides were also evaluated. Insulin levels were significantly higher in the obese group, whereas levels of growth hormone were significantly lower. Moreover, a more adverse lipid profile was observed in overweight patients. This was associated with higher hematocrit values. At Doppler analysis, a significantly higher mean uterine artery pulsatility index (PI) was observed in the obese group. Furthermore, the PI was inversely correlated with high density lipoprotein values (r = -0.4820; p < 0.05). In both groups, androstenedione was correlated with the uterine PI. The above findings may, in part, explain the increased risk in women with PCOS of developing cardiovascular diseases, and emphasize that obesity may further increase the risk.

Adult↗
PubMed1996

Effects of L-arginine on utero-placental circulation in growth-retarded fetuses.

BACKGROUND: To evaluate the effects of L-arginine (ARG) infusion, the nitric oxide as substrate, on the utero-placental circulation at third trimester. METHODS: Three groups of nine pregnant women each were infused i.v. with 30 g ARG, for 30 minutes. One group served as control, and the two remnants were composed by patients with intrauterine growth retardation with (IUGR-B) or without (IUGR-A) increased resistances in the utero-placental circulation. Changes of blood flow velocity waveforms of both uterine arteries and umbilical artery were recorded for 60 minutes. Blood pressure, serum nitrites/nitrates and growth hormone levels were also measured. RESULTS: No hemodynamic changes in utero-umbilical circulation were observed during infusion in any of the three groups. Considering the uterine arteries separately as placental and non-placental sided we found a significant decrease of non-placental side resistances in IUGR-B women. Indeed, the pulsatility index was lowered by 14%, in respect of baseline value. Serum nitrites/nitrates as well as serum growth hormone levels were significantly increased by ARG, in every woman, irrespective of the presence of fetal growth retardation. Blood pressure remained unaffected during infusion in every woman. CONCLUSIONS: These findings suggest that L-arginine infusion affects utero-placental circulation in patients with IUGR associated with increased uterine resistances. Such an action is specific and appears possibly to be mediated by a release of nitric oxide.

Adult↗
PubMed1995

Melanocortins and opioids modulate early postnatal growth in rats.

This study was undertaken to investigate the effects of melanocortins and opioids on rat early postnatal body and organ growth. Among melanocortins tested desacetyl-alpha-melanocyte-stimulating hormone (alpha-MSH) at dosages of 0.3 and 3 micrograms/g/day was effective in stimulating neonatal growth with a weight gain of 7 and 5.6%, respectively, after 2 weeks of treatment. Likewise, a weight rise of 4.2 and 3% was obtained with 3 micrograms/g/day of both alpha-MSH and Nle4-D-Phe7 alpha-MSH. As far as opioids were concerned, while N-acetyl-beta-endorphin (beta-End) was ineffective, the activity of beta-End was dependent on dosage. Indeed, newborns treated with 0.03 microgram/g/day showed a slight, but significant, increase in weight, whereas a marked decrease in growth followed treatment with 0.3 and, mainly, 3 micrograms/g/day, with a final weight loss of 3.4 and 5.5%, respectively. All melanocortins exerted a positive action on muscular and brain trophism and, in addition, desacetyl-alpha-MSH also induced a rise of fat deposits. On the contrary, while the 0.03 microgram/g/day beta-End dose caused an increase in muscular and brain weight, the higher dosages of the opioid were detrimental, not only for muscle and brain, but also for both liver and spleen weight. A slight, although significant (P < 0.05), enhancement of serum dehydroepiandrosterone sulfate (DHEAS) level was found after the injection of 0.3 microgram/g desacetyl-alpha-MSH, whereas both the 0.3 and 3 micrograms/g doses of desacetyl-alpha-MSH and the 3 micrograms/g dose of alpha-MSH determined the rise of plasma androstenedione (P < 0.05). All tested melanocortins and opioids failed to modify the concentrations of corticosterone. Our results suggest that melanocortins and opioids can modulate early postnatal growth in rats either by direct or indirect mechanisms.

Adipose Tissue↗
PubMed1995

A comparative, randomized study of three different progesterone support of the luteal phase following IVF/ET program.

The use of luteal phase support has been demonstrated in patients undergoing IVF/ET in cycles stimulated after pituitary desensitization with gonadotrophin releasing hormone agonists. However, it is still not clear which is the most suitable kind of supplementation. This study was designed to compare the absorption and the efficacy of three different luteal support. We randomly administered progesterone i.m. (50 mg/day), human chorionic gonadotrophin (hCG) (2000 IU every three days), progesterone vaginal cream (100 mg/day) or nothing (controls) to 176 women treated for assisted procreation. We were not able to show any statistical differences for the percentage of pregnancy rate between groups. The serum progesterone (P) and 17-beta-estradiol (E2) and E2/P ratio levels of the luteal phase were compared with the control not supplemented group. All the treatments were able to increase significantly the luteal P values versus controls (p < 0.01). Moreover, vaginal cream and natural P im significantly decreased E2/P ratio (p < 0.05). Serum P levels were more steady with P vaginal cream than im injection. Vaginal cream for better bioavailability and acceptance appear the most suitable and comfortable method for luteal phase support.

Adult↗
PubMed1995

Obstetric and perinatal outcome in human immunodeficiency virus-infected pregnant women with and without opiate addiction.

This study was undertaken to assess the impact on gestation played by the simple human immunodeficiency virus (HIV)-seropositive status either alone or complicated by opiate abuse in the absence of other confounding variables. To this purpose the main obstetric complications and the perinatal outcome were prospectively evaluated in 38 simple HIV-infected women, 14 of whom were simple carriers and 24 under methadone treatment, and in 76 uninfected women, 16 of whom were methadone users and 60 controls. In simple HIV-carriers maternal weight gain (P < 0.001) and both 1- and 5-min Apgar scores (P < 0.005) were reduced whereas the incidence of miscarriage was increased (P < 0.05). Worse obstetric and perinatal outcomes were found in HIV-seropositive drug addicts, in which gestational length (P < 0.001), maternal weight gain (P < 0.001) and Apgar scores were lower (P < 0.005 and P < 0.001, respectively) and the rate of preterm labour, small for gestational age newborns, vaginal and urinary infections as well as of unexplained fever (P < 0.05) was higher. Outcomes were similar in HIV-seropositive and seronegative drug addicts and in both groups a positive correlation (r = 0.62 P < 0.001, and r = 0.44, respectively) was found between the number of infectious episodes throughout pregnancy and the mean dose of opiate consumed daily. Our results suggest that HIV-seropositive condition might exert slight direct and indirect detrimental effects on pregnancy. Whatever the maternal serologic status, opiate intake not only causes a further worsening of gestational and perinatal outcomes, but also increases the susceptibility towards pathogens.

Female↗
PubMed1995

Transvaginal estriol administration in postmenopausal women: a double blind comparative study of two different doses.

A group of 72 postmenopausal women were treated for 4 weeks with vaginal suppositories containing 0.5 or 1.0 mg of estriol. The two different doses achieved an identical significant improvement of urogenital symptoms, while a dose-related effect seen to be on climacteric complaints, according to a good absorption of estriol by the vaginal epithelium. Minimal side effects were observed and the safety of vaginal estriol treatment could advise further study about the effect of this kind of treatment on the climacteric syndrome.

Administration, Intravaginal↗
PubMed1995

Naltrexone administration modulates the neuroendocrine control of luteinizing hormone secretion in hypothalamic amenorrhoea.

Because endogenous opioids have been considered to be deeply involved as a causal factor of hypothalamic amenorrhoea, this study was designed to evaluate the efficacy of the administration of naltrexone, an antagonist of opioid receptors, on luteinizing hormone (LH) secretion in patients with hypothalamic amenorrhoea. A total of 30 patients with hypothalamic amenorrhoea were studied. Patients were divided into two groups: group A, hypogonadotrophic (n = 15), and group B, normogonadotrophic (n = 15). All patients were administered naltrexone at a dose of 50 mg/ day per os for 6 months. A third group of 10 amenorrhoeic patients was treated with placebo per os with the same schedule. All patients were evaluated for LH spontaneous pulsatile release in baseline conditions and after 3 and 6 months of treatment. Plasma gonadal steroid concentrations increased significantly in all patients after 3 months of naltrexone therapy, but only hypogonadotrophic patients showed a sharp increase in both LH plasma concentrations and LH pulse amplitude within the first 3 months of treatment which remained unchanged until the sixth month of treatment. Plasma follicle stimulating hormone concentrations did not change significantly in any patient. Menstrual bleeding occurred within 90 days of the beginning of treatment in 24 out of the 30 patients. Patients treated with placebo did not show a significant change in gonadotrophin and gonadal steroid plasma concentrations. The results of our study support the efficacy of naltrexone administration on neuroendocrine pathways controlling LH secretion in patients with hypothalamic amenorrhoea.

Amenorrhea↗