Biomedical subjects

A Volpe

Publications and source records attributed to A Volpe.

At least 73 records · Page 4Linked to original sources

PubMed2000

Increased L-citrulline/L-arginine plasma ratio in severe preeclampsia.

OBJECTIVE: To evaluate nitric oxide (NO) production in patients with pregnancy-induced hypertension or preeclampsia and in controls. METHODS: Four groups of pregnant women were included: 17 patients with pregnancy-induced hypertension, ten with mild or moderate preeclampsia, 17 with severe preeclampsia, and 44 normotensive women matched for weeks of gestation at blood sampling with the cases. Plasma levels of L-citrulline and L-arginine were measured by using high-performance liquid chromatography. RESULTS: The mean plasma levels of L-citrulline and the ratio of L-citrulline to L-arginine, which reflects NO production, were higher in women with severe preeclampsia than in controls, patients with pregnancy-induced hypertension, and patients with mild or moderate preeclampsia. CONCLUSION: Nitric oxide production is enhanced in severe preeclampsia, possibly as a compensatory phenomenon for the increased synthesis and release of vasoconstrictors and platelet-aggregating agents.

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

Influence of exogenous melatonin on catecholamine levels in postmenopausal women prior and during oestradiol replacement.

OBJECTIVE: In young individuals melatonin administration reduces circulating norepinephrine. Some effects of melatonin are reduced in elderly women and are modulated by gonadal steroids. Accordingly, the influence of melatonin on catecholamine levels was investigated in postmenopausal women without and with oestradiol replacement. DESIGN: Prior to and after 2 months of transdermal oestradiol (50 microg/day), women were studied on two consecutive days, on which they received placebo or 1 mg of melatonin orally in a randomised and double-blind fashion. PATIENTS: Fourteen healthy postmenopausal women. MEASUREMENTS: Resting levels of epinephrine and norepinephrine and their responses to both a cold stimulus, performed by placing a hand in a basin of water and ice for 2 minutes, and to 10 minutes of upright position (upright test). RESULTS: Prior to oestradiol, melatonin did not modify baseline or stimulated catecholamine levels. In contrast, during oestradiol, melatonin tended to reduce, although not significantly, baseline norepinephrine levels (P = 0.053), and significantly reduced peak values (P = 0.0061) and integrated norepinephrine response (P = 0.0076) to the cold stimulus. Responses of norepinephrine to the upright test were not modified, while those of epinephrine were increased (P = 0.042). During, but not prior to oestradiol replacement, modifications induced by melatonin (melatonin day-placebo day) in the norepinephrine response to the cold (r2 = 0. 457; P = 0.0079) and the upright (r2 = 0.747; P = 0.0001) tests were linearly and inversely related to the responses of the placebo day. CONCLUSIONS: Melatonin does not modulate adrenergic activity in postmenopausal women without hormone replacement therapy. Oestradiol replacement restores the capability of melatonin to modulate adrenergic activity, particularly the norepinephrine response to stimuli.

Catecholamines↗

PubMed2000

Hepatitis C virus serotypes in haemodialysis patients in South-East Italy.

Hepatitis C virus (HCV) infection is highly prevalent in haemodialysis patients. To date, only a few studies involving a small number of subjects have characterized HCV-infected dialysis patients by serotyping. The spread of HCV serotypes in 114 HCV-positive dialysis patients from the same geographical area was evaluated by Murex HCV serotyping assay. Serotypes were detected in 102 subjects (89.5%), with type 1 being the most frequent (37.7%), followed by types 2 (19.3%), 4 (8.8%) and 3 (7.9%). Types 5 and 6 were the least prevalent (3.5%). Ten samples (8.8%) revealed mixed infections: type 1 was detectable in all and the co-infecting HCV types were types 2, 3 and 4 in 3, 4 and 3 cases, respectively. These results suggest that the serotyping assay as an alternative method of distinguishing the major types of HCV, also for particular risk groups and especially in laboratories that lack the specific expertise to perform genotyping methods. Age-related differences in patients with type 5 compared with those with types 3 and 6 may provide evidence of a more recent spread of these latter types.

Adult↗

PubMed2000

Platelet responsiveness to L-arginine in hypertensive disorders of pregnancy.

OBJECTIVE: In chronically hypertensive (CH), preeclamptic (PE), and normotensive pregnant women (N), we investigated ex vivo platelet aggregation in response to L-arginine (L-Arg) and sodium nitroprusside (SN), which are respectively the substrate and donor of nitric oxide (NO). METHODS: Platelet aggregation was determined with a dual-channel aggregometer by measuring transmittance of light through the sample in comparison to platelet poor plasma, as a reference. Aggregation induced by adenosine diphosphate was continuously recorded for 3 min and measured before and after preincubation with L-Arg and SN. RESULTS: Preincubation with L-Arg significantly reduced platelet aggregation in N and CH patients (p < 0.05) but not in PE women. Preincubation with SN affected aggregation in PE women also (p < 0.001). No correlation was found between platelet response to L-Arg or SN stimuli and the severity of hypertensive disorders expressed as week of gestation at delivery or birth weight. CONCLUSIONS: The present study demonstrates that a decreased platelet sensitivity to L-Arg characterizes PE women, whereas SN maintains its antithrombotic power. This impairment seems to be specific for PE, because platelets of CH patients utilize L-Arg normally. This finding supports the involvement of the L-Arg-NO pathway in the pathogenesis of the procoagulative features of PE and probably in the onset of the disease. The maintained response to SN in PE patients suggests a possible therapeutical use of NO donors in the disease.

Adult↗

PubMed2000

Chemical ripening of the cervix with intracervical application of sodium nitroprusside: a randomized controlled trial.

Nitric oxide (NO) has been found to be involved in the processes of cervical ripening. In a randomized, placebo-controlled study, cervical softening by an intracervical application of sodium nitroprusside, one of the most clinically potent and effective NO donor agents, was evaluated. A total of 36 primigravid women undergoing pregnancy termination between 9 and 12.5 weeks were enrolled. In one series, 18 patients were randomized to receive intracervically either placebo or 1% nitroprusside gel (5 mg), followed by uterine evacuation 6 h after treatment. In another series, 18 patients received either placebo or 2% nitroprusside gel (10 mg) into the cervical canal followed by uterine evacuation 3 h later. The cervical resistance, i.e. the force required to dilate the cervix from 3 to 10 mm, was the main outcome variable. It was recorded using a force sensing apparatus (dynamometer). Blood pressure was measured. Adverse events were recorded until 2 h after surgery. Women treated with both doses of nitroprusside gel showed values of cervical resistance significantly lower than those treated with placebo gel, at any tested diameter. No differences were found between subjects treated with the two different doses of nitroprusside. No significant consistent changes in blood pressure were induced by either dose of nitroprusside. No headaches were found in subjects treated with the NO donor. This study demonstrates that sodium nitroprusside applied into the cervical canal induces a rapid and significant softening of the cervix, thus reducing the force required to dilate it, compared with placebo-treated subjects. The chemical ripening of the cervix with sodium nitroprusside intracervical gel is an efficacious procedure in first-trimester pregnancy.

Abortion, Induced↗

PubMed2000

Seminal plasma nitrite/nitrate and intratesticular Doppler flow in fertile and infertile subjects.

The objective of the present study was prospectively to evaluate the role of nitric oxide (NO) in modulating intratesticular blood flow and sperm function. A total of 56 males, undergoing assisted reproduction, were divided into three groups according to semen analysis: (i) normozoospermic (n = 16); (ii) oligozoospermic (n = 21); and (iii) azoospermic (n = 19). All the subjects were submitted to hormone analysis [luteinizing hormone, follicle stimulating hormone (FSH), growth hormone, testosterone, androstenedione, insulin], and to ultrasonographic (testicular volume) and Doppler (transmediastinal artery) evaluations. Plasma and seminal plasma nitrite/nitrate concentrations, and plasma insulin-like growth factor-I were assayed. All 56 patients completed the study. In normozoospermic patients, significantly greater testicular volume, lower transmediastinal resistances, and higher seminal plasma nitrite/nitrate concentrations were observed in comparison with both oligo- and azoospermic subjects. Testicular volume was inversely correlated with plasma FSH (r = -0.589; P = 0.005) and pulsatility index of transmediastinal artery (r = -0.402; P = 0.049). Furthermore, the seminal plasma nitrite/nitrate concentrations were inversely correlated with pulsatility index of transmediastinal artery (r = -0.511; P = 0.015). It was concluded that NO is involved in vascular modulation of testicular vessels and ultimately in sperm output.

Adult↗

PubMed2000

Indirect evidence that estrogen replacement therapy stimulates nitric oxide synthase in postmenopausal women.

The aim of the study was to investigate the effects of estrogen replacement therapy (ERT) on nitric oxide (NO) activity in healthy postmenopausal women. The study group consisted of 22 postmenopausal women (last menses at least 12 months prior to study entry) who were randomized to receive treatment for 2 months with patches that delivered either 50 micrograms/day of 17 beta-estradiol or placebo in a cross-over design. Blood samples for measurements of serum citrulline and arginine were collected at the start of the study and at the end of each treatment course. Serum citrulline and arginine were measured using high-performance liquid chromatography with fluorometric detection. Arginine levels were significantly lower in the ERT group compared to the placebo group, while citrulline levels did not change. The percentage citrulline/arginine ratio was significantly higher in the ERT group (42.9 +/- 21.6) compared to the placebo group (33.9 +/- 18.5) (p < 0.01). The citrulline/arginine ratio, both at baseline and during either ERT or placebo administration demonstrated a positive linear correlation with body mass index (BMI). No correlations were found between follicle stimulating hormone, estradiol and insulin levels and BMI. No correlations were found between age, time since menopause and baseline arginine and citrulline levels or the citrulline/arginine ratio. These data indirectly demonstrate that transdermal estradiol replacement in postmenopausal women is able to stimulate NO production through the involvement of endogenous L-arginine. A positive linear correlation was found between BMI and the citrulline/arginine ratio, suggesting an additional protective cardiovascular effect in overweight women.

Arginine↗

PubMed2000

Allergic reaction to a highly purified urinary follicle stimulating hormone preparation in controlled ovarian hyperstimulation for in vitro fertilization.

We report a case of general hypersensitivity-like allergic reactions to intramuscular injections of highly purified urinary follicle stimulating hormone (uFSH-HP) successfully managed by using intramuscular recombinant FSH (rFSH). The patient underwent a first cycle of in vitro fertilization (IVF) and controlled ovarian hyperstimulation (COH) was achieved with a combination of gonadotropin releasing hormone against (GnRH-a) and uFSH-HP. Because, after oocyte recovery, no fertilization occurred, the couple subsequently entered an intracytoplasmic sperm injection (ICSI) program. During the COH, the woman developed general hypersensitivity-like allergic reactions with itching, redness and swelling. Although there was regular follicular growth, the allergic symptoms worsened and, on day 8 of COH, the stimulation cycle was suspended. A few months later, the patient entered a new ICSI cycle. COH was achieved by using a combination of GnRH-a and rFSH. The cycle was completed and the patient did not report any allergic reaction. To avoid allergic reaction to the protein components of the urine-derived FSH preparations, the use of rFSH is suggested in those patients who present local and/or general hypersensitivity-like allergic reactions.

Adult↗

PubMed2000

The use of a starting dose of recombinant follicle stimulating hormone for controlled ovarian hyperstimulation: a randomized pilot study.

The aim of this study was to compare the costs and effects of two different controlled ovarian hyperstimulation treatments: a starting dose of recombinant follicle stimulating hormone (FSH) followed by highly purified urinary FSH; or highly purified urinary FSH alone. Forty-six infertile patients, after being given luteal gonadotropin-releasing hormone (GnRH) agonist, were randomly assigned to the two stimulation protocols. During the ovarian stimulation regimen the patients underwent transvaginal ultrasonographic evaluation of follicular number and size. The retrieved oocytes were classified on the basis of the criteria of Acosta and colleagues. To study the impact of embryo quality on implantation, the embryos were graded morphologically before replacement. Pregnancy rates were ascertained and the costs of the two different protocols were analyzed. The number of days of FSH stimulation and the cost of gonadotropin treatment were similar in both groups. The number of follicles > 17 mm in size, the number of collected oocytes, and pregnancy rate per cycle were significantly higher in the group partially treated with recombinant gonadotropin. We conclude from these results that the use of recombinant FSH in the early phase of controlled ovarian hyperstimulation leads to significant improvements in pregnancy rate per cycle without increasing the costs of treatment.

Adult↗

PubMed2000

Polycystic ovary syndrome: a new ultrasonographic and color Doppler pattern.

The aim of this study was to evaluate whether patients with partial bilateral polycystic ovaries show different ovarian and uterine blood flow to those with complete bilateral polycystic ovaries, and to investigate whether there is a correlation between ultrasonographic and hormonal parameters. Fifteen patients with partial polycystic ovaries and eighteen patients with complete bilateral polycystic ovaries underwent clinical, biochemical, gray-scale and color Doppler ultrasonographic evaluation. Hormonal (luteinizing hormone (LH), follicle-stimulating hormone (FSH), LH/FSH concentration ratio, estradiol, prolactin, androstenedione, testosterone), clinical (body mass index, Ferriman-Gallwey score), ultrasonographic (ovarian volume, number and distribution of subcapsular follicles, stromal score) and Doppler (uterine artery and intraparenchymal vessels pulsatility index, ovarian stromal vascularization) parameters were evaluated, in the early follicular phase (cycle day 3-5) in oligomenorrheic patients, or at random in amenorrheic patients. Significantly higher androstenedione plasma levels and LH/FSH concentration ratios were observed in complete bilateral polycystic ovaries. In partial polycystic ovaries, gray-scale and color Doppler ultrasonography showed different features in affected and unaffected areas of the ovary, similar to polycystic and normal ovary appearance respectively. In conclusion, PCOS does not predetermine a single ultrasonographic or Doppler pattern.

Adult↗

PubMed2000

[Aspects of thrombophilia in Buerger's disease].

Buerger's disease or thromboangiitis obliterans is a disorder of unknown etiology which affects young heavy smokers, mainly of male sex; it is not clear why this disease afflicts only a little number of heavy smokers. Studies about genetic predisposition, autoimmune phenomena and platelet function have been performed in order to search additional etiologic factors without finding significant alterations. Recently some cases of Buerger's disease in association with hypercoagulable states have been described. The authors reported ten subjects affected by Buerger's disease, who have undergone to a clotting process evaluation. We have found 3 cases with fasting hyperhomocysteinemia in association with low level of plasma folate, 3 cases with high value of lipoprotein(a) (in 1 subject in association with IgG anticardiolipin antibody positivity), 1 case with IgM anticardiolipin antibody positivity. These findings, along with literature data, induce to hypothesize that hypercoagulable states may favour the clinical expression of Buerger's disease.

Adjuvants, Immunologic↗

PubMed2000

[Nephron-sparing treatment of kidney neoplasms in transplanted kidney. Our experience].

BACKGROUND: To evaluate survival rate, follow-up and renal function in patients treated with "nephron-sparing" approach due to cancer in a transplanted kidney. METHODS: During the 18 years' activity of our Transplantation Centre 3 renal carcinomas in transplanted kidneys (0.24%) have been found. Diagnoses were made in one case during transplantation procedures and, in the remaining two, 1 month and 10 years after. All tumours were unifocal, small (10, 12 and 18 mm of diameter), capsulated and low stage (T1). The resection of the mass ("nephron-sparing" surgery) and of a layer (1 cm thick) of the tissue surrounding the tumour was performed. The histological exam showed in all cases low grade (G2) renal cell carcinoma and negative surgical margins. RESULTS: 138, 94 and 15 months after transplant all patients are alive, without disease recurrence and with good renal function. In all cases the doses of immune-suppressive therapy were reduced. CONCLUSIONS: Renal cancer in transplanted kidneys is generally treated with nephrectomy. On the contrary, we decided to apply the same criteria which are accepted for the treatment of renal neoplasms in general and then to perform a "nephron-sparing" surgery when the tumour is small, capsulated and with negative surgical margins at the intraoperative histological exam. In personal experience good results from the oncologic and nephrologic point of view have been accomplished.

Carcinoma, Renal Cell↗

PubMed2000

Use of small calibre JJ ureteral stent with anti-reflux valve in uretero-vesical anastomosis during renal transplantation.

BACKGROUND: We report our experience in transplantation proceedings with the use of small caliber JJ ureteral stent with antireflux valve during uretero-vesical anastomosis. METHODS: During renal transplantations we usually perform an uretero-cystoneostomy with antireflux technique according to Lich Gregoir. In the past we used to intubate the uretero-vesical anastomosis only in particular cases; since April 1998 we performed 112 single and 8 double transplants and in all cases we positioned a 12 cm long paediatric 4.8 Ch JJ ureteral stent with antireflux valve, in order to reduce urologic complications. The vesical catheter was usually removed in 6o-7o day and the ureteral stent 40-60 days after transplantation. RESULTS: We have performed 129 uretero-vesical anastomoses and we complained only one case of early dehiscence of the anastomosis (unilateral in a double transplant) and two cases of late stents' displacement. We noticed no stenosis of the anastomosis and no dysfunction in urine outflow from the upper urinary ways. CONCLUSIONS: The routinary use of paediatric JJ ureteral stents with antireflux valve was decisive in drastically reducing early urologic complications after renal transplantation. Furthermore, the risk of vesico-ureteral reflux is almost completely reduced, thanks to the technique adopted for the anastomosis which allows a physiologic-like antireflux mechanism, to the presence of the antireflux valve and to the early recovery of the physiologic ureteral peristalsis, which is promoted by the small calibre of the stent. These factors lead to a faster recovery of the renal function, with excellent results from the nephrologic and urologic points of view.

Anastomosis, Surgical↗

PubMed1999

Effect of prolonged administration of transdermal estradiol on flow-mediated endothelium-dependent and endothelium-independent vasodilation in healthy postmenopausal women.

In 15 postmenopausal women with no cardiovascular risk factors, hormone replacement with transdermal estradiol (50 microg/day for 2 months) did not enhance flow-mediated endothelium-dependent vasodilation, reduce endothelium-independent vasodilation, and did not modify the pulsatility index and blood flow of the brachial artery. The present data do not support a positive effect of replacement with transdermal estradiol on vessel vasodilation in healthy, postmenopausal women.

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 long-term local or systemic hormone replacement therapy on post-menopausal mood disturbances. Influences of socio-economic and personality factors.

OBJECTIVES: To clarify the effect exerted by hormone replacement therapy (HRT) versus socio-economic and personality factors in improving postmenopausal mood disorders. STUDY DESIGN: The effect of the 1-year administration of systemic hormone replacement therapy (HRT; n = 22) or a vaginal cream of estriol (n = 14) versus no treatment (n = 26) was evaluated on mood states of anxiety, depression, somatization and inadequacy, as evaluated by the symptom rating test (SRT) scale. Results were correlated with the woman socio-economic status, and her capability to cope with daytime distresses, as evaluated by the Coping Style questionnaire. RESULTS: A spontaneous decline of all SRT scores, except that of inadequacy, was observed in the group with no treatment. In comparison HRT induced a greater improvement of only the SRT score of inadequacy (P < 0.01) and to a lesser extent of anxiety (P < 0.06). Similarly, vaginal estriol induced a greater decline of the SRT score of inadequacy (P < 0.01). Multiple regression analysis showed that modifications of the total SRT score and the SRT score of anxiety were related mainly to socio-economic factors, while those of the SRT score of depression were related only to the coping style of the woman. The decline of somatization was related only to time since the menopause while, the reduction of the SRT score of inadequacy was only the consequence of therapy, either systemic or local. CONCLUSIONS: In a 1-year period improvement of post-menopausal psychological discomfort, is spontaneous and independent of therapy. Only symptoms of inadequacy are improved by the hormonal therapy. Likely, the perceived menopausal 'losses' make the woman to feel inadequate and the use of sex-related hormones is capable to improve this feeling.

Adaptation, Psychological↗

PubMed1999

First-trimester fetal sex prediction by deoxyribonucleic acid analysis of maternal peripheral blood.

OBJECTIVES: We investigated whether the number of weeks of gestation influences the accuracy of first-trimester fetal sex prediction by analysis of deoxyribonucleic acid extracted from whole maternal blood. A comparison was also made to determine whether a difference exists between this approach and the deoxyribonucleic acid analysis of transcervical cells performed on the same group of subjects. STUDY DESIGN: Deoxyribonucleic acid was isolated from 50 maternal blood samples taken between gestational weeks 7 and 11. The sex of the fetus was assessed by nested polymerase chain reaction specific for the amelogenin gene. A receiver-operating characteristic curve analysis was used to correlate the accuracy of fetal gender prediction with the gestational age and also to compare the goodness of the 2 methods under investigation. RESULTS: Analysis of the receiver-operating characteristic curve provided a cutoff value of 9 weeks 4 days of gestation for both tests, indicating that a higher degree of accuracy in the sex assignment was obtained in those samples taken before or at this time. However, this difference was statistically significant only for analysis of deoxyribonucleic acid from maternal blood. The comparison between tests of deoxyribonucleic acid from maternal blood and from transcervical cells showed that the first approach is better, although a statistically significant difference was not found. CONCLUSION: Analysis of maternal blood deoxyribonucleic acid is a better approach than analysis of trans-cervical cell deoxyribonucleic acid in fetal sex prediction. The highest degree of accuracy is obtained when blood is drawn before 10 weeks of gestation. This can be important when sampling of chorionic villi should be avoided because of the risk of an X-linked disease when the fetal sex is female.

Amelogenin↗