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A Revelli

Publications and source records attributed to A Revelli.

At least 19 recordsLinked to original sources
PubMed2006

Construction of an evidence-based integrated morphology cleavage embryo score for implantation potential of embryos scored and transferred on day 2 after oocyte retrieval.

BACKGROUND: Evidence-based morphological embryo scoring models for ranking of implantation potential are still scarce, and the need for a precise model increases when aiming for singleton pregnancies. METHODS: Prospectively, 2266 IVF/ICSI double-embryo, day 2 transfers were studied. The five variables scored in 3- to 5-step scales for the embryos transferred are blastomere number (BL), fragmentation, blastomere size variation ('equality', EQ), symmetry of the cleavage and mononuclearity in the blastomeres (NU). The scoring results of embryos with an individual traceability from scoring to implantation, i.e. treatments resulting in either no implantation (n=1385) or twin implantation (n=228), were studied for prognostic potential. RESULTS: Although all five variables correlated highly with implantation potential, only BL, NU and EQ remained independently significant after regression analysis. The equation thus derived formed the basis for a 10-point integrated morphology cleavage (IMC) embryo score. A table with the scoring point for each possible combination of the embryo variables is presented. The scoring model was statistically validated on the singleton pregnancy group (n=653). CONCLUSIONS: We suggest that this IMC embryo scoring, incorporating cleavage stage and information on the variation in blastomere size and the number of mononucleated blastomeres, may optimize embryo ranking and selection for day 2 transfers.

Adult↗
PubMed2006

Oocytes cryopreservation: state of art.

In the present review article we sought to analyze, on the basis of a systematic review, the indications, rationale of oocytes cryopreservation, as well as the techniques that improved the aforementioned procedure in order to higher the pregnancy rate in women undergoing that procedure. Moreover, we pointed out the importance of oocytes cryopreservation in the research field as oocyte banking may be of utmost importance to increase the availability of oocytes for research applications such as genetic engineering or embryo cloning. Oocyte freezing has 25 year of history alternating successes and setbacks. Human oocytes have a delicate architecture but are freezable. Clinical efficiency remains low, but healthy children have been born, indicating that chromosomally normal embryos can originate from frozen oocytes. Freezing protocols are not yet optimal and it is now desirable to combine empirical and theoretical knowledge.

Cryopreservation↗
PubMed2006

Fertility in patients with multiple sclerosis: current knowledge and future perspectives.

The issue of fertility in patients with multiple sclerosis (MS) has not been exhaustively studied. Epidemiological data have suggested that spontaneous fecundity might be reduced; several endocrine and sexual disturbances potentially interfering with reproduction have been evidenced in MS patients of both sexes. Moreover, some medical treatments used in MS (e. g., mitoxantrone, cyclophosphamide) may exert detrimental effects on spermatozoa as well as on oocytes, leading to early impairment of fertility. This review illustrates the factors potentially interfering with fertility in MS and discusses the therapeutic tools that may be used to promote fertility in these patients. The safety of hormonal therapies in MS is also examined. The current applications of assisted reproductive technology (ART) are discussed, including in vitro fertilisation (IVF) techniques. Currently available methods to preserve fertility in patients that undergo cytotoxic treatments by means of sperm/oocyte cryostorage or by ovarian fragment cryopreservation and autografting are considered.

Antineoplastic Agents↗
PubMed2005

Preserved insulin sensitivity and {beta}-cell activity, but decreased glucose effectiveness in normal-weight women with the polycystic ovary syndrome.

Insulin resistance and hyperinsulinemia are often considered intrinsic features of the polycystic ovary syndrome (PCOS). Nevertheless, conflicting results of insulin sensitivity and secretion have been obtained in the subgroup of normal-weight women with PCOS. Differences in body composition, ethnicity, and diet composition and a family history of metabolic diseases may act as confounding variables in women with PCOS. In the present study, insulin sensitivity and secretion were estimated by an iv glucose tolerance test (IVGTT), analyzed by minimal models, in 20 normal-weight healthy women with PCOS and no family history of type 2 diabetes mellitus and in 20 normally ovulating women, matched for age and body mass index. Insulin sensitivity [mean (95% confidence intervals); PCOS 4.0 (2.8-5.1) vs. controls 4.5 (3.5-5.4) 10(-4) min(-1)/microU.ml], and insulin secretion, expressed as the acute insulin response to glucose [PCOS 3.7 (3.3-4.2) vs. controls 3.7 (3.4-4.0) microU/ml] were similar in the two groups. The women with PCOS showed an increased proportion of total body fat (PCOS 29% vs. controls 27.2%; P < 0.01). They also showed decreased glucose effectiveness, i.e. the proportion of glucose uptake independent from insulin activity [PCOS 2.6 (2.1-3.0) vs. controls 3.8 (3.0-4.6) mg x 100 min(-1); P = 0.01]. The levels of insulin sensitivity and of glucose effectiveness did not correlate in either group. Whether the isolated finding of decreased glucose effectiveness could reflect an early stage in the development of the metabolic aberrations often associated with the syndrome remains to be clarified.

Adult↗
PubMed2001

The concentration of nitrite in seminal plasma does not correlate with sperm concentration, sperm motility, leukocytospermia, or sperm culture.

OBJECTIVE: To correlate the concentration of nitrite (the stable metabolite of nitric oxide) in seminal plasma with sperm number and motility, leukocytospermia, and sperm culture. DESIGN: Prospective study. SETTING: Academic research institution. PATIENT(S): Seventy normozoospermic or dyspermic men enrolled in an artificial insemination/in vitro fertilization program. INTERVENTION(S): Semen samples (n = 70) were checked for sperm concentration, total sperm count, sperm motility, seminal leukocyte concentration, and sperm culture; similarly, the concentration of nitrite in seminal plasma was measured by Griess reaction. MAIN OUTCOME MEASURE(S): Measurement of nitrite concentration in seminal plasma and its correlation with sperm concentration, total sperm count, sperm motility, leukocytospermia, and sperm culture. RESULT(S): The concentration of nitrite in seminal plasma does not correlate with sperm concentration, total sperm count, or with the proportion of immotile or rapid-forward motile spermatozoa. Moreover, the concentration of nitrite in seminal plasma is not significantly increased when sperm culture is positive, nor does it correlate with leukocyte concentration in semen. CONCLUSION(S): Our results do not support the hypothesis that in vivo nitric oxide synthesis affects sperm function; alternatively, our results could suggest that nitrite in the seminal plasma is not a sensitive marker of in vivo nitric oxide synthesis.

Fertilization in Vitro↗
PubMed2001

Chemotactic responsiveness of human spermatozoa to follicular fluid is enhanced by capacitation but is impaired in dyspermic semen.

PURPOSE: Our purpose was to study the chemotactic responsiveness of human spermatozoa from normal and pathological semen samples to follicular fluid (FF), as well as the effect exerted by capacitation on sperm chemotaxis. METHODS: The chemotactic responsiveness of human spermatozoa to FF was tested by an accumulation assay chamber in which they were allowed to migrate through a microporous membrane and accumulate in a compartment filled with FF or control medium. The percentage of cells with hyperactivated motility among migrated sperm was objectively assessed by CASA and its relationship to the accumulation rate was studied. Single FFs were tested with single normospermic or dyspermic semen samples; the same FF was tested with different semen specimens. The influence of capacitation onto the chemotactic responsiveness to FF was investigated by comparing the accumulation rate of spermatozoa from normal and pathological samples after incubation under capacitating conditions for 1 or 6 hr. RESULTS: Some FFs ("active" FFs) effectively attracted human spermatozoa from normospermic samples up to a dilution factor of 1:500 (v:v) with control medium. A wide range of responses was observed when the same FF was tested with different normal semen samples. A longer time under capacitating conditions increased both the chemotactic responsiveness of normal semen and its ability to undergo the acrosome reaction (AR) in response to A23187. Pathological semen had an impaired chemotactic responsiveness to "active" FF that was not enhanced by increasing the time spent under capacitating conditions. Dyspermic semen was also less responsive to A23187, a finding suggesting incomplete capacitation. CONCLUSIONS: Chemotactic responsiveness to FF is acquired in parallel to or as part of the capacitation process. Dyspermic semen samples have an impaired capacity to achieve both capacitation and chemotactic responsiveness to follicular factors.

Calcimycin↗
PubMed2001

Signaling pathway of nitric oxide-induced acrosome reaction in human spermatozoa.

Nitric oxide (NO) has been recently shown to modulate in vitro motility, viability, the acrosome reaction (AR), and metabolism of spermatozoa in various mammalian species, but the mechanism or mechanisms through which it influences sperm functions has not been clarified. In human capacitated spermatozoa, both the intracellular cGMP level and the percentage of AR-positive cells were significantly increased after 4 h of incubation with the NO donor, sodium nitroprusside (SNP). SNP-induced AR was significantly reduced in the presence of the soluble guanylate cyclase (sGC) inhibitors, LY83583 and ODQ; this block was bypassed by adding 8-bromo-cGMP, a cell-permeating cGMP analogue, to the incubation medium. Finally, Rp-8-Br-cGMPS and Rp-8-pCPT-cGMPS, two inhibitors of the cGMP-dependent protein kinases (PKGs), inhibited the SNP-induced AR. Furthermore, SNP-induced AR did not occur in Ca2+ -free medium or in the presence of the protein kinase C (PKC) inhibitor, calphostin C. This study suggests that the AR-inducing effect of exogenous NO on capacitated human spermatozoa is accomplished via stimulation of an NO-sensitive sGC, cGMP synthesis, and PKG activation. In this effect the activation of PKC is also involved, and the presence of extracellular Ca2+ is required.

Acrosome Reaction↗
PubMed1999

Follicular fluid proteins stimulate nitric oxide (NO) synthesis in human sperm: a possible role for NO in acrosomal reaction.

Nitric oxide (NO) is a free radical involved in the regulation of several functions of the male genitourinary system. It is produced by neurons and the endothelium and epithelia of reproductive system; it mediates penile erection and regulates sperm motility, viability, and metabolism. Here we show that human spermatozoa exhibit a detectable NO synthase (NOS) activity, measured both as ability of the intact sperm and cell lysate to convert L-[3H]arginine into L-[3H]citrulline and as 24 h accumulation of extracellular nitrite in intact sperm suspensions. NOS activity (identified as an endothelial isoform) was inhibited by L-canavanine and N(G)-monomethyl-L-arginine, and nitrite accumulation was inhibited by the NO scavenger hemoglobin; both enzyme activity and nitrite production were increased by a 24 h incubation of spermatozoa with protein-enriched extracts of human follicular fluid (PFF); a significant increase of citrulline synthesis was observed only after a 4 h incubation with 40% PFF, a time period during which acrosomal reactivity was significantly increased. PFF-induced acrosomal reaction was inhibited by L-canavanine and hemoglobin, and the NO donors sodium nitroprusside (SNP), S-nitroso-N-acetyl-penicillamine (SNAP), and DETA NONOate were able to increase the percentage of reacted spermatozoa. Our results suggest that NO synthesized by human sperm may play a role in follicular fluid-induced acrosomal reaction.

Acrosome Reaction↗
PubMed1999

Microinjection of mitochondria into zygotes creates a model for studying the inheritance of mitochondrial DNA during preimplantation development.

OBJECTIVE: To determine the effect of mutant mitochondria on preimplantation embryo development and of preimplantation embryo development on the survival of mutant mitochondrial DNA. DESIGN: Laboratory research. SETTING: Academic research laboratory. PATIENT(S): None. INTERVENTION(S): Mutant and wild-type mitochondria, fractionated from tissue obtained from a patient with MELAS syndrome, a mitochondrial disease, were microinjected into mouse zygotes. Control zygotes received either no injection or sham injection. MAIN OUTCOME MEASURE(S): Preimplantation embryo development and survival of mutant mitochondrial DNA as determined by polymerase chain reaction analysis. RESULT(S): After microinjection into zygotes, the MELAS mutation could be identified by polymerase chain reaction until the hatched blastocyst stage of embryo development. The survival of MELAS-injected zygotes, observed for 4 days after injection, did not differ from the survival of zygotes injected with wild-type mitochondria or from the survival of uninjected or sham-injected controls. CONCLUSION(S): It appears that preimplantation embryo development does not screen out mitochondrial DNA mutations introduced into fertilized oocytes, and low levels of mutant mitochondrial DNA do not disrupt early embryo development.

Animals↗
PubMed1998

Nongenomic effects of neurosteroids.

This review summarizes the current knowledge about the synthesis, the mechanism of action, and the effects of neurosteroids in the central nervous system. Particular attention is paid to the nongenomic actions of neurosteroids, which are discussed in relation to their clinical relevance for physiological and pathological states.

Anesthetics↗
PubMed1998

Atrial septal defect and pregnancy: a retrospective analysis of obstetrical outcome before and after surgical correction.

STUDY OBJECTIVES: To describe the obstetrical outcome and long-term cardiac follow-up of a group of patients who had surgery for atrial septal defect repair before pregnancy and a group who underwent pregnancy before surgical correction. DESIGN: Retrospective. SETTING: Public Institution. PATIENTS: Eighty women (mean age 20.15 +/- 4.5 years) complaining of atrial septal defect, 60 of which had surgical correction before pregnancy and subsequently had 115 pregnancies, and 20 of which underwent pregnancy before the correction of cardiac defect and subsequently had 48 pregnancies. INTERVENTIONS: Surgical correction of atrial septal defect: 49 by open heart technique (13 with cardiopulmonary bypass, 36 with light hypothermic circulatory arrest), 11 by closed heart techniques. RESULTS: Patients who underwent pregnancy before surgery had an increased incidence of miscarriage, pre-term delivery and cardiac symptoms during pregnancy. Patients operated before pregnancy required more frequently cesarean section and pharmacological therapy. The frequency of stillbirths, malformations in the offspring and long-term cardiac complications were similar in both groups. CONCLUSIONS: Surgical correction of atrial septal defect before pregnancy is recommended even in case of apparently well compensated hemodinamic situation for the low rate of surgical complications in spite of the higher incidence of obstetrical problems in case of medical therapy alone.

Adult↗
PubMed1997

Sex steroid binding protein receptor (SBP-R) is related to a reduced proliferation rate in human breast cancer.

In the last years, an increasing amount of studies described a membrane receptor for the Sex Steroid Binding Protein (SBP) on several androgen-estrogen dependent tissues. One of the suggested biological roles of the interaction between SBP and its receptor seems to be a negative control of the E2 induced proliferation of human breast cancer cells through the cAMP pathway. In the present work, SBP membrane receptor was evaluated on human breast cancer specimens with a radio-binding assay. Each tissue sample was also evaluated for ER and PGR status. Cytosol Thymidine Kinase levels were measured in tissue samples in order to evaluate cell proliferation rate. SBP binding to membranes of ER +/PGR + samples was time and temperature dependent, specific and at high affinity. In addition, SBP recognized on breast cancer membranes two sites at different affinity, as previously described for other human tissues and cultured cells. Membrane SBP-R was detected in a significantly higher number of samples positive for both ER and PGR than in negative samples. SBP-R positive samples showed a significantly lower proliferation rate than SBP-R negative samples as demonstrated by TK activity. The present study contains evidences for the existence of a specific membrane receptor for SBP in breast cancer sample membranes and the presence of SBP-R seems to be strictly related to a lower proliferation rate of the sample.

Breast Neoplasms↗
PubMed1996

In situ hybridization study of messenger RNA for estrogen receptor and immunohistochemical detection of estrogen and progesterone receptors in the human ovary.

The expression of estrogen and progesterone receptors (ER and PR), as well as the presence of messenger RNA for estrogen receptor (ER-mRNA), were analyzed by immunohistochemistry and in situ hybridization, respectively, in the ovary of 25 healthy eumenorrheic women. Ovarian biopsies were taken in different phases of the menstrual cycle during laparotomy or operative laparoscopy performed for extraovarian benign diseases. A total of 126 follicles (105 primordial, 13 preantral and eight antral) and 50 corpora lutea (eight active and 42 atretic) was analyzed. Granulosa cells stained positively for ER, PR and ER-mRNA in 13.3, 9.5 and 17.1% of primordial follicles, respectively. The proportions of preantral and antral follicles with ER-positive granulosa cells were 23.1 and 37.5%, respectively; these follicles were positive for PR in 23.1 and 37.5% of cases, and for ER-mRNA in 30.7 and 37.5% of cases, respectively. For thecal cells, 38.5% of preantral and 37.5% of antral follicles were PR-positive, but no more than 25% stained positive for ER and ER-mRNA. Active corpora lutea stained positive for ER, PR and ER-mRNA in 50, 62.5 and 50% of cases, respectively. Corpora albicantes always stained negative. In all subjects the stroma surrounding both follicles and corpora lutea contained several fibroblast-like cells which stained positive for ER, PR and ER-mRNA. Oocytes and blood vessels stained negative in all cases. This study supports the hypothesis that estrogens and progesterone play a role in the intraovarian regulation of follicle growth from the first steps of follicle development, and participate in the regulation of corpus luteum.

Adult↗
PubMed1995

Effect of peritoneal fluid, follicular fluid, and their volumetric mixture on acrosomal reactivity in vitro.

OBJECTIVE: To determine the effects of peritoneal and follicular fluids (PFs, FFs) on sperm acrosomal reaction (AR). DESIGN: Prospective, randomized study. SETTING: Three hospital-based infertility units. PATIENTS: Twenty-three women participating in GIFT programs; 23 men participating in AIH programs. INTERVENTIONS: Hormonal stimulation after buserelin desensitation; laparoscopy 36 hrs after hCG injection. MAIN OUTCOME MEASURE: Percentage of acrosomally-reacted sperm. RESULTS: Compared with Earle's medium (control), moderate but significant increases of ARs were observed as function 1) of the relative content of FF in the incubation medium and 2) as function of time (these increases were constantly lower than those registered for the respective positive control, i.e. 2x frozen/thawed sperm). In contrast, when PF alone was present in the incubation medium, no such effects on AR were registered. CONCLUSIONS: FF and mixtures of PF and FF--but not PF alone--seem to induce some rapid and time-dependent processes which finally lead to an AR. Therefore, and independently on the infertility cause (tubal, male-dependent, unexplained infertility), PF seems able to exert effects on sperm motility (Revelli et al., Fertil. Steril 57, 654-60 [1992]) while maintaining an unreacted sperm status.

Acrosome↗
PubMed1995

Recurrent endometriosis: a review of biological and clinical aspects.

The recurrence of pelvic endometriosis some time after the initial treatment is a common finding in clinical practice. When symptoms of endometriosis reappear several months after treatment, it is difficult to distinguish between recurrence and persistence of the disease. In this review, the current hypotheses about the biological basis of endometriosis recurrence/persistence are discussed. The results of several clinical trials estimating the recurrence rate of endometriosis after medical, surgical, and combined treatments are presented. In addition, a critical analysis of the tools available for the diagnosis of recurrent endometriosis is made, and some therapeutic options to treat recurrent endometriosis are discussed with recommendations for their use.

Endometriosis↗
PubMed1994

Binding of sex steroid binding protein to plasma membranes of human testis.

The existence of a specific binding site for sex steroid binding protein (SBP or SHBG) was detected on plasma membranes prepared from the testis of a patient affected by a variant form of testicular feminization. A binding technique using [125I]SBP as a tracer allowed us to identify a single set of binding sites, characterized by a Kd of 1.917 x 10(-11) M. The maximum number of binding sites was 5.2 fmol/mg membrane protein. Membranes were also prepared from a sample of genital skin from the same patient, but no binding for [125I]SBP was detectable. The evidence of the SBP membrane receptor in the testis of a patient affected by Morris syndrome extends our knowledge about the tissue distribution of the SBP receptor and suggests the possible implication of SBP and its recognition system in a disorder related to peripheral androgen insensitivity.

Androgen-Insensitivity Syndrome↗
PubMed1994

Steroid gradients across the cancerous breast: an index of altered steroid metabolism in breast cancer?

The concentrations of 17 beta-estradiol, estrone, testosterone (T), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate, androstenedione (A), cortisol and prolactin (PRL) were determined in the peripheral venous blood and in the lateral thoracic vein of 14 premenopausal and 34 postmenopausal women who underwent surgery for a breast carcinoma. The difference between the two blood samples, defined as concentration gradient across the cancerous breast, was calculated for all hormones. A significant peripheral-local concentration gradient was found for DHEA and A both in pre- and postmenopausal patients, whereas for T it was observed only in postmenopausal subjects. Furthermore, DHEA and A gradients were correlated to the presence of estrogen receptors as determined by a radioligand binding assay. An inverse relationship between DHEA gradient and the expression of estrogen receptors was observed in premenopausal women, whereas in postmenopausal patients an opposite, although not significant, trend was found. These results suggest that in the cancerous breast: (1) DHEA, A and T (the latter only in postmenopause) could be taken up from plasma, and thus there could be a storage of these steroids inside the breast tissue and/or perhaps some alterations in their local metabolism; (2) androgens could play a different role in breast carcinogenesis in relation to the estrogen circulating levels and to the expression of estrogen receptors.

Adult↗