Search PubMed⌕ Search

Biomedical subjects

G B La Sala

Publications and source records attributed to G B La Sala.

At least 19 recordsLinked to original sources

Different glycoforms of the human GPI-anchored antigen CD52 associate differently with lipid microdomains in leukocytes and sperm membranes.

CD52 is a human GPI-anchored antigen, expressed exclusively in the immune system and part of the reproductive system (epididymal cells). Sperm cells acquire the antigen from the epididymal secretions when transiting in the epididymal corpus and cauda. The peptide backbone of CD52, consisting of only 12 aminoacids, is generally considered no more than a scaffold for post-translational modifications, such as GPI-anchor and especially N-glycosylation which occur at the third asparagine. The latter modification is highly heterogeneous, especially in the reproductive system, giving rise to many different glycoforms, some of which are tissue specific. A peculiar O-glycan-containing glycoform is also found in reproductive and immune systems. We determined to locate CD52 in microdomains of leukocytes and sperm membranes using two antibodies: (1) CAMPATH-1G, the epitope of which includes the last three aminoacids and part of the GPI-anchor of glycoforms present in leukocytes and sperm cells; (2) anti-gp20, the epitope of which belongs to the unique O-glycan-bearing glycoform also present in both cell types. Using a Brij 98 solubilization protocol and sucrose gradient partition we demonstrated that the CD52 glycoforms recognized by both antibodies are markers of typical raft microdomains in leukocytes, whereas in capacitated sperm the O-glycoform is included in GM3-rich microdomains different from the cholesterol and GM1-rich lipid rafts with which CAMPATH antigen is stably associated. The importance of the association between GM3 and O-glycans for formation of specialized microdomains was confirmed by heterologous CD52 insertion experiments. When prostasomes from human seminal fluid were incubated with rat sperm from different epididymal regions, the CD52 glycoform recognized by anti-gp20 decorated rat epididymal corpus and cauda sperm, associated with the same low-cholesterol GM3-rich sperm membrane fractions as in human sperm. The glycoforms recognized by CAMPATH-1G were not found in rat sperm. The relationship between this differential insertion and differences in glycosylation of rat and human CD52 is discussed.

Antigens, CD↗

Lower embryonic loss rates among twin gestations following assisted reproduction.

PURPOSE: To determine whether maternal age and number of transferred embryos influence early pregnancy losses in twin pregnancies compared to singletons following IVF/ICSI. METHODS: We compared the pregnancy loss rates in singleton (n = 549) and twin (n = 252) gestations, stratified by maternal age (< or = 35 and > 35 years) and the number of transferred embryos (1-3 and 4-9). RESULTS: Loss rates of singleton pregnancies were significantly higher than that in twins (OR 3.0, 95% CI 1.9, 4.9), especially among singletons conceived after transfer of 4-9 embryos (OR 5.0, 95% CI 2.2, 11.9). Younger mothers of twins had lower loss rates (OR 0.3, 95% CI 0.1, 0.9). CONCLUSION: Twins have a significantly reduced spontaneous miscarriage rate compared with singletons following IVF/ICSI. Higher implantation rates per cycle (i.e., development of twins rather than one live embryo) may represent a better capacity of the uterus for early embryonic development.

Abortion, Spontaneous↗

Epitope analysis of immunoglobulins against gp20, a GPI-anchored protein of the human sperm surface homologous to leukocyte antigen CD52.

Gp20 is a sialylglycoprotein of the human sperm surface related to maturation and capacitation and is homologous to CD52, a glycosyl- phosphatidyl-inositol (GPI)-anchored protein highly expressed in lymphocytes, monocytes, eosinophils, and epididymal cells, described by the monoclonal antibody family CAMPATH. The CAMPATH antigen is characterized by a very short peptide (12 amino acids) and an N-linked oligosaccharide chain bound to the asparagine located in the third position and a GPI anchor bound to the C-terminal serine. The CAMPATH epitope includes three amino acids at the C-terminus and part of the GPI anchor. It has been suggested that anti-gp20 interacts with the same peptide recognized by CAMPATH antibodies but with a different epitope, since it describes the corresponding antigen in a different way. For example, it localizes the corresponding antigen in the equatorial region of the sperm head when sperm are capacitated, whereas CAMPATH antibodies bind all over the sperm surface. Our results indicate that the anti-gp20 epitope does not include the peptide backbone, the GPI anchor, or the N-glycans but consists of O-linked oligosaccharide chains bound to a unique CD52 glycoform present both in sperm and leukocytes. This is suggested by results obtained using many different approaches, such as immunoblot analysis of gp20 after removal of N- and O-glycans and after jacalin (Artocarpus integrifolia agglutinin)-affinity chromatography.

Alemtuzumab↗

Gp273, the ligand molecule for sperm-egg interaction in the bivalve mollusk, Unio elongatulus, binds to and induces acrosome reaction in human spermatozoa through a protein kinase C-dependent pathway.

In a previous article, we suggested that gp273, the ligand molecule for sperm-egg interaction in the bivalve mollusk Unio elongatulus has functional carbohydrate epitopes in common with a human zona pellucida glycoprotein, probably ZP3. We demonstrated that: 1) anti-gp273-purified immunoglobulin G (IgG), which recognizes a carbohydrate gp273 epitope including a Lewisa-like structure, interacts with a zona pellucida protein; 2) human sperm specifically bind to gp273; and 3) binding is reversed by anti-gp273 IgG. In the present study, we confirm this suggestion by demonstrating that heat-solubilized zonae pellucidae reverse gp273-human sperm binding, that gp273-binding sites are restricted to the acrosomal region, and that gp273 induces the acrosome reaction in human sperm. We also demonstrated that gp273-binding sites on human sperm function as signaling receptors because exposure of spermatozoa to this glycoprotein results in significant stimulation of protein kinase C (PKC) activity. Because the PKC inhibitor, bisindolylmaleimide I, reverses both PKC activation and the acrosome reaction, this kinase is a key component of the signal transduction pathway activated by gp273 and leading to the exocytotic event.

Acrosome Reaction↗

Surface of human sperm bears three differently charged CD52 forms, two of which remain stably bound to sperm after capacitation.

gp20 is a sialoglycoprotein of the human sperm surface with a core peptide homologous to the leukocyte antigen CD52, a GPI-anchored glycosylated protein which is described by the monoclonal antibody CAMPATH-1. Comparative analyses, by means of CAMPATH and anti-gp20, indicated that they describe it in morphologically and functionally different ways, suggesting that the respective epitopes are different but also casting doubt on the immunological identity of the antigen. In the present study, we used immunodepletion to demonstrate that CAMPATH and anti-gp20 interact with the same antigen, but that anti-gp20 has a much higher avidity for the antigen than CAMPATH. Anion exchange fractionation analysis of the antigen revealed three differently charged gp20-CD52 forms, the least charged of which, was largely without a GPI-anchor. All three forms were associated with freshly ejaculated sperm, whereas capacitated sperm only contained the two GPI-anchored, more charged forms, which were also the ones found in the prostasome fraction of seminal plasma and in leukocytes. The two charged, GPI-anchored forms were described as homogeneous by anti-gp20, since they ran as a singlet; the third form ran as a doublet. When tested for insertion into Jurkat T cells, the medium charged form inserted the most readily and the less charged one could not be inserted at all.

Antibody Specificity↗

Follicular fluid as a favourable environment for endometrial and endometriotic cell growth in vitro.

Follicular fluid from women with endometriosis has been shown to induce a higher endometrial cell proliferation than that derived from women without the disease. To elucidate this issue further, the aims of the present study were to compare the ability of follicular fluid and peritoneal fluid to stimulate both endometrial and endometriotic cell proliferation and to verify whether the mitogenic effect was merely sex steroid-dependent. Endometrial and endometriotic cells were cultured in follicular fluid or peritoneal fluid diluted in serum-free media; the growth induced in these conditions was compared with that obtained by culturing these cells in medium supplemented with charcoal stripped calf serum and a correspondent content of 17-beta-oestradiol and progesterone. Follicular fluid was able to induce significantly higher cell proliferation than peritoneal fluid from controls, patients with endometriosis stage I-II and women with endometriosis stage III-IV (P < 0.05). Moreover, the growth in control media containing a corresponding amount of steroid hormones was significantly lower than that obtained with follicular or peritoneal fluids. This finding indicates that the stimulating effect is not simply related to the concentrations of 17-beta-oestradiol and progesterone present in these fluids. Finally, based on these results and on other previous observations, the hypothesis that follicular fluid may be involved in the development of endometriotic ovarian cysts is discussed.

Adult↗

Carbohydrate-mediated sperm-egg interaction and species specificity: a clue from the Unio elongatulus model.

As a first step fertilization requires that sperm bind to the extracellular coat of the egg. It is generally accepted that binding is mediated by complex carbohydrates on the egg coat, recognized by carbohydrate-binding proteins on the sperm surface. In the mollusc bivalve Unio elongatulus, the main functional epitope of the carbohydrate ligand has been determined, and it shares several characteristics with other sugar structures involved in the fertilization process in different animal models. A polyclonal antibody against the Unio epitope reacts with the human ZP3 glycoprotein and the Unio ligand binds human spermatozoa in an in vitro assay. These findings are discussed in the light of the species specificity of sperm-egg binding at fertilization.

Animals↗

[Incidence of chromosomal anomalies and congenital malformations in children born from assisted fertilization].

The introduction and widespread application of Assisted Reproductive Techniques (ART) have raised major concern about the offspring 's health. The incidence of congenital and chromosomal anomalies after standard In Vitro Fertilization and Embryo Transfer seems to be similar to that expected in the general population. The prevalence of congenital malformations does not seem to be higher in children conceived by ICSI. On the other hand, it seems that there is a slight risk for transmission of chromosomal aberration of paternal origin and a certain risk of de novo sex-chromosomal and structural aberrations after ICSI. We report the results of the follow-up of 938 children conceived in our public ART by standard IVF(649) and by ICSI(289) from 21-2-1987 to 30-6-1999. The incidence of the congenital malformations results of the 1.8% (17/938); the incidence of chromosomal anomalies results 0.5% (5/938). The incidence of congenital malformations and chromosomal anomalies results 1.5% (10/649) and 0.6% (4/649), respectively, for standard IVF and 2.4% (7/289) and 0.3% (1/289) for ICSI. Our data seems to be reassuring but the incidence of chromosomal anomalies in ICSI children needs further investigation.

Chromosome Aberrations↗

Evidence of mild respiratory disease in men with congenital absence of the vas deferens.

Cystic fibrosis (CF) is a severe disorder, whose main characteristics are, in addition to congenital absence of the vas deferens (CAVD), progressive lung disease, pancreatic insufficiency and elevated sweat chloride levels; CAVD without any other manifest clinical evidence is commonly suggested to be a form of CF with primarily genital expression. We undertook this study to test the hypothesis that men with a CAVD phenotype could be more CF-like than it is usually assumed. Each subject from a population of 42 patients suffering from CAVD was screened for a panel of 16 mutations plus the intron 8 5-thymidine allele of the CF gene (5T), and underwent a thorough clinical evaluation which included a detailed anamnesis, anthropometric data, chest and paranasal sinuses X-rays, pulmonary function tests, sputum cultures, stool chymotrypsin determination, sweat test and, in a limited number of patients, Nasal Potential Difference (NPD) measurement. The genotype analysis detected one compound heterozygote, 23 heterozygotes and 15 individuals carrying the 5T allele; sweat chloride was positive in six, borderline in 11 and negative in 25 subjects; NPD was abnormal in 2/12 patients. Medical history and clinical examination were consistent with respiratory disease in 20 cases; there was radiological evidence of pulmonary hyperinflation in 37/39 and of sinus disease in 20/42 patients; Staphylococcus aureus was cultivated in the sputum of 9/36, Haemophilus influentiae in 3/36 subjects and three patients showed functional evidence of airway obstruction. These findings were equally distributed among sweat positive, borderline and negative patients. These results raise questions about the supposed benignancy of the CAVD condition. A close follow-up of men with CAVD could ascertain potential complications.

Adult↗

Anxiety and perceptive functioning of infertile women during in-vitro fertilization: exploratory survey of an Italian sample.

The aim of this study was to study the emotional impact of in-vitro fertilization (IVF) and any possible influence due to the type of diagnosis, duration of infertility, number of cycles and type of responses to treatment. The study was carried out on 200 patients admitted to hospital for the final stages of IVF (oocyte retrieval and embryo transfer). The psychological measures taken into consideration were: state and trait anxiety levels (Stait-Trait Anxiety), unconscious and symptomatic anxiety, perception of self and of others (EWI). Monitoring of anxiety levels during hospitalization highlighted significant differences with respect to the state anxiety values (P < 0.01) and general anxiety (P < 0.05), but not with respect to trait anxiety. The level of state anxiety of women with a diagnosis of infertility was significantly lower (P < 0. 05). Women who have experienced infertility of medium to long duration presented a significantly lower state anxiety value (P < 0. 01). The failure of oocyte fertilization determines a significant increase in state anxiety level (P < 0.01) There were no significant differences in anxiety values with respect to the cycle number. Perceptive functioning was normal.

Adult↗

Sperm treatment with extracellular ATP increases fertilization rates in in-vitro fertilization for male factor infertility.

Previous work from our laboratory has revealed that extracellular ATP is a rapid and potent activator of human sperm acrosome reaction and fertilizing ability. In the present study, we assessed the effects of in-vitro sperm incubation with ATP on fertilization and embryo development in couples undergoing in-vitro fertilization (IVF) for male factor infertility. Oocytes from 22 women undergoing ovulation induction were divided in two groups and inseminated in vitro either with selected spermatozoa from the corresponding partner suffering from male factor infertility pre-incubated with ATP (2.5 mM) for 1 h, or with spermatozoa incubated with 0.9% NaCl solution (control group). After insemination, fertilization was assessed by the presence of pronuclei and then by embryo cleavage. The fertilization rate in the group of oocytes inseminated with ATP-treated spermatozoa improved significantly with respect to the control group (65.7 versus 42.5%, P < 0.01). No significant differences were observed in embryo cleavage and embryo quality. Embryos from both treated and control groups were transferred together in 20 transfer procedures, and in two couples fertilization was not obtained. Nine pregnancies occurred: one biochemical, one miscarriage, and seven patients delivered 9 healthy babies. Two pregnancies were twin with an overall pregnancy rate of 40.9% per cycle and of 45% per transfer. In conclusion, the results of the present study demonstrate that, in humans, extracellular ATP induces a significant increase of sperm fertilizing potential, as these findings are a rationale for the use of ATP for in-vitro treatment of human spermatozoa during IVF.

Adenosine Triphosphate↗

The role of diagnostic hysteroscopy and endometrial biopsy in assisted reproductive technologies.

OBJECTIVE: To study the incidence of unsuspected endouterine abnormalities in patients for whom IVF-ET repeatedly fails. DESIGN: Prospective study. SETTING: Infertility Unit of the Department of Obstetrics and Gynecology, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy. PATIENT(S): One hundred patients for whom two IVF-ET cycles failed in which > or =2 good-quality embryos were transferred. INTERVENTION(S): In-office diagnostic hysteroscopy and endometrial biopsy. MAIN OUTCOME MEASURE(S): Relation between IVF-ET failure and unsuspected endouterine abnormalities. RESULT(S): In 18 patients, hysteroscopy showed an important unsuspected endouterine abnormality. Fifteen of these patients did not become pregnant after IVF-ET, and 3 became pregnant but had a spontaneous abortion. Histologic examination of the endometrium revealed chronic endometritis in 1 patient and tuberculous endometritis in another. CONCLUSION(S): Previous studies have reported that the incidence of endouterine abnormalities is high in patients undergoing IVF-ET. Our data confirm the previous reports and lead us to conclude that diagnostic hysteroscopy should be performed on all patients before they undergo IVF-ET.

Adult↗

Psychological adjustment of infertile women entering IVF treatment: differentiating aspects and influencing factors.

OBJECTIVE: To evaluate the psychological adjustment of infertile women compared with a control group of mothers and to determine which personal or marital factors influence the amount of emotional disorders in the infertile group. DESIGN: Cross-sectional questionnaire study with a group of infertile women and a group of mothers attending a routine gynecological examination. SETTING: Infertile women and mothers received the questionnaires after a psychological or medical examination respectively, at a Sterility Center in a Department of Obstetrics and Gynaecology. PARTICIPANTS: One hundred and twenty-two infertile women, entering an IVF program, and 57 mothers attending a routine care visit. MAIN OUTCOME MEASURES: Stressful events, self-esteem, job and marital satisfaction, care and control measures of intimate bond, state-trait anxiety, depression, psychophysiological symptoms and global emotional factor scores. RESULTS: The organic infertile group was higher than mothers on satisfaction with their relationship with their husbands, perception of care and state-anxiety. The emotional factor scores of infertile women, controlled for stressful events, were influenced by a) number of IVF-cycles and availability for adoption, b) job position, job satisfaction and self-esteem, c) personality dimensions. State and trait anxiety scores were influenced by the level of global marital satisfaction. CONCLUSIONS: Infertile women, entering an IVF treatment program, do not necessarily show signs of psychological maladjustment. Their level of state-anxiety can be considered a situational response to the treatment stress. The infertility condition and its treatment can be effectively dealt with by women having a good personality disposition, a high level of self-esteem, who are satisfied with their job and relationship with their husband, and who are willing to adopt a child as a last solution for their maternal need.

Adaptation, Psychological↗

Efficacy and tolerability of brodimoprim at two different dosage schedules in the treatment of acute uncomplicated bacterial cystitis: comparative study vs. pefloxacin.

In an open study, 172 male and female adult patients with acute uncomplicated bacterial cystitis were randomly allocated to three treatment groups. Two groups received brodimoprim 200 mg tablets as follows: a single dose of two 200 mg tablets on day 1, followed by one tablet per day on days 2 and 3 (58 patients); or a single daily dose of two tablets, for 2 days (63 patients). The third group received a single dose of pefloxacin, as two 400 mg tablets, for 1 day (51 patients). Complete urinalysis, sediment and urine culture examinations were carried out before treatment and 10 days after the last dose. Evaluation also comprised, at the time of enrolment and 48 h after the last dose, measurement of corporal temperature and assessment of symptoms (dysuria, pollakiuria, strangury, suprapubic pain, burning sensation during urination and urgency) on a 4-point scale. The eradication rate for the pathogen concerned was 98.3% and 96.7% in the groups receiving brodimoprim for 3 and 2 days, respectively, and 92.8% in the pefloxacin group (between-group comparison n.s.). There was significant regression of symptoms (P < 0.001) in the three groups (between-groups comparison n.s.). Mainly gastrointestinal adverse events occurred in 3 patients receiving brodimoprim for 2 days and in 4 patients from each of the other two groups.

Acute Disease↗

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↗

Recurrent empty follicle syndrome.

We report a case of recurrent empty follicle syndrome over two stimulated cycles in a patient having immunological infertility. All follicles contained follicular fluid but aspirated granulosa cells were rarely observed. No oocytes were obtained from a total of 24 follicles.

Adult↗

Noninvasive evaluation of cardiovascular hemodynamics during multiple follicular stimulation, late luteal phase and early pregnancy.

A noninvasive hemodynamic study in three moments of the gamete intrafallopian transfer (GIFT) cycle was carried out on 25 patients: before beginning multiple follicular stimulation (MFS) (study I); after rapid increase of serum estradiol (E2) (study II); and 12 days after GIFT (study III). In the 25 patients, the rapid increase in E2 proved to be combined with a significant increase in the left ventricular end diastolic dimension (LVEDD), the left ventricular end systolic dimension, the heart rate (HR), the systolic index, the cardiac index, and a significant reduction in the mean arterial pressure, in the systolic arterial pressure and in the systemic vascular resistence index. In the 14 pregnant patients in study III, all of the hemodynamic parameters studied proved to be significantly modified with respect to study I. In the 11 nonpregnant patients between Studies I and III were no significant cardiovascular modifications except for a significant increase in LVEDD in Study III. It is concluded that, during MFS, the rapid increase in E2 is combined with hemodynamic modifications and that, in pregnancy, the cardiovascular adaptation modifications occur in the very early stages.

Adult↗