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C Giorgetti

Publications and source records attributed to C Giorgetti.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Comparison of optical analysis and computerized analysis of sperm movement in a program of 316 in vitro fertilizations].

The purpose of this study was to compare visual and computerized assisted semen analysis (CASA) in an in vitro fertilization program. Both methods were performed on the day of 316 oocyte retrievals. CASA was performed using a Hamilton 7.2 device adjusted in accordance with the settings defined by a group of 14 French centers. Despite a few discrepancies, the correlation between visual and CASA sperm counts was significant (p < 0.001), so that between the two total motility assessments. The same correlation (Pearson's test) was observed between the fertilization rate and the parameters obtained by visual analysis and CASA. VAP, VSL, VCL and ALH exhibited threshold values under which the mean fertilization rate was below 50%. This study demonstrates the satisfactory reliability of CASA although it cannot yet replace visual analysis.

Diagnosis, Computer-Assisted↗
PubMed1993

Subzonal sperm insemination and total or extreme asthenozoospermia: an effective technique for an uncommon cause of male infertility.

OBJECTIVE: To assess the value of subzonal insemination (SUZI) in cases of total or extreme asthenozoospermia. DESIGN: The results of IVF after SUZI were assessed in six cycles (four couples) with documented asthenozoospermia. SETTING: Institut de Médecine de la Reproduction, Marseille, France. PATIENTS: Four couples underwent six retrieval cycles. In all cases asthenozoospermia was total (100% of immotile spermatozoa) or extreme (5% nonprogressive motility). Oligozoospermia and teratozoospermia were ruled out in all cases. In two cases electron microscopy revealed the absence of the central singlet in the flagellum axonemal complex and in one case a major dysplasia of the fibrous sheath in the flagellum principal piece. RESULTS: The overall fertilization rate was 45%. The diploid embryo rate was 33%. Embryo quality was satisfactory. In five of six cycles, three embryos were transferred. Two triplet pregnancies were obtained corresponding to an implantation rate per transferred embryo of 40%. CONCLUSION: Total or extreme asthenozoospermia seems to be a good indication for SUZI.

Adult↗
PubMed1993

Partial zona dissection enhances the fertilization rate in cases of sperm defect only when total failure has occurred in previous in-vitro fertilization attempts.

The value of partial zona dissection (PZD) was assessed in a randomized protocol of in-vitro fertilization (IVF) including 30 couples (44 cycles) with at least two sperm defects. Couples were divided into three groups according to previous IVF status, i.e. group I: total failure of previous IVF; group II: marginal success of previous IVF, and group III: no previous IVF. Both PZD and untreated oocytes were inseminated using the swim-across method. Although PZD did not enhance the overall proportion of fertilized eggs resulting in diploid cleaving embryos per retrieved oocyte (14.7 versus 17.1%), this rate was higher with PZD than with IVF when previous IVF attempts had failed (group I: 16.1 versus 4.5%, P < 0.01). The rate was similar for PZD and IVF in group II, and lower for PZD than IVF in group III (15.1 versus 30.8%, P < 0.01). The higher polyspermy rate associated with PZD in groups in which classical IVF worked, could partially explain these results. The role of a possible deleterious effect of PZD on the oocytes is discussed. Out of the 44 cycles, 20 reached the embryo transfer stage and four pregnancies were obtained. In our opinion PZD should be carried out in cases of sperm defects only when previous IVF attempts have failed.

Embryo Transfer↗
PubMed1992

Thrombomodulin is a cofactor for thrombin degradation of recombinant single-chain urokinase plasminogen activator "in vitro" and in a perfused rabbit heart model.

Thrombin cleaves single-chain urokinase-type plasminogen activator (scu-PA) to a two-chain derivative (tcu-PA) fibrinolytically inactive. This reaction was accelerated in vitro by purified rabbit lung thrombomodulin in equimolar complex with thrombin. Polyclonal antibodies to rabbit thrombomodulin prevented this effect. We also observed that heparin and other sulfated polysaccharides had an accelerating effect on thrombin cleavage of recombinant scu-PA. Their effect was concentration-dependent and then reversed at high levels. The effect of heparin and heparan sulfate was independent and synergic with respect to thrombomodulin. All observations except the effect of heparin, could be confirmed in a Langendorff isolated rabbit heart model. From competition experiments carried out with scu-PA derivatives and mutants, we postulate that the amino-terminal sequence of rscu-PA, containing the epidermal growth factor (EGF)-like and the kringle domains is involved in the cofactor effect of thrombomodulin on scu-PA inactivation by thrombin. We conclude that a regulatory mechanism of scu-PA inactivation is present at the cell surface.

Animals↗
PubMed1992

Quantified ultrastructural study of spermatozoa in unexplained failure of in vitro fertilization.

Failure of in vitro fertilization or very low cleavage rates may occur even though oocyte and semen parameters seem satisfactory. Quantified ultrastructural study of spermatozoa was performed in such cases of failure (n = 6) or low cleavage rate (< 20%; n = 4). Through 1 to 11 retrievals, the number of inseminated oocytes ranged from 14 to 145. The results were compared to those of six fertile men. Quantification was achieved by cataloguing cell defects of the spermatozoon heads and mid-/principal pieces of the flagella. Using the data from each specimen, the percentages of total cellular abnormalities in the head/mid-/principal pieces were established. At the level of the head overall percentages for six groups of defects were determined. The overall percentage of combined head abnormalities, defined as the presence of at least three of these six defects on the same spermatozoon head, was established. Statistical differences among control and patient groups were analyzed by nonparametric Mann-Whitney U test. The percentages of anomalies of the midpiece and of the principal piece were not significantly different between patients and controls. Motility assessed by spermogram was considered "functionally uncompromised." In eight patients the percentage of cell alterations of the head (93-100 vs 77.3 +/- 6.4%) and the percentage of combined anomalies of the head (78.1-100 vs 60.8 +/- 8.5%) were significantly different between patients and controls. In two cases, the percentages established for all head parameters considered were not globally different from those observed in controls. Thus in 8 cases of 10, electron microscopy with quantified analysis supplied valuable evidence about the poor quality of these sperm samples judged as normal under light microscopy and may provide an explanation for their impaired fertilizability.(ABSTRACT TRUNCATED AT 250 WORDS)

Fertilization in Vitro↗
PubMed1992

In-vitro fertilization in cases with severe sperm defect: use of a swim-across technique and medium supplemented with follicular fluid.

The purpose of this study was to evaluate a new method of in-vitro fertilization (IVF) in patients with severe sperm defects. Unlike the conventional swim-up method, spermatozoa and oocytes are placed in opposite corners of the bottom of the incubation dish so that sperm swimming is horizontal instead of vertical. Another difference between the swim-across and swim-up techniques is that the incubation medium is supplemented with 20% follicular fluid. After a randomized series (protocol I) of 15 IVF attempts had demonstrated that swim-across was more effective than swim-up in terms of fertilization and cleavage, we began a second series (protocol II) using only swim-across. A total of 124 couples with motile sperm counts less than 1 x 10(6) spermatozoa/ml of semen were included in protocol II. Clinical parameters (age, tubal damage) and number of recovered oocytes were recorded and compared in patients who did (group A: n = 94) and did not (group B: n = 74) achieve fertilization. In group A the fertilization rate was 36.7% and, out of the 94 transfers that were made, there were 21 clinical pregnancies and 12 full-term pregnancies with 16 live births. The number of oocytes collected (12 versus 7.7, P less than 0.001) and the incidence of tubal damage (50% versus 24.3%, P less than 0.001) was significantly higher in group A than in group B. Using logistic regression analysis, we showed a significant correlation between fertilization and progressive motility, percentage normal spermatozoa, number of recovered oocytes and tubal damage.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1990

Neonatal and adult primary B cells use the same germ-line VH and V kappa genes in their (T,G)-A-L-specific repertoire.

Although there is a nonrandom usage of VH gene families by primary B cells early in ontogeny, at issue is whether the preferential rearrangement of 3' germ-line VH genes, e.g., VH7183 and VHQ52 family genes, influences the neonatal B cell repertoire that can be expressed in response to Ag. In order to address this issue, and to determine whether neonatal B cells can use the same germ-line VH and V kappa genes as adult B cells in their primary response, we have analyzed at the molecular level the neonatal antibody response to (T,G)-A-L and compared it with the adult primary response. Among the TGB5 Id+, GT+ antibodies, which dominate the neonatal response to (T,G)-A-L, two VH gene families were used: J558 (high frequency) and 36-60 (low frequency). The majority of Id+ neonatal hybridomas used the same germ-line VH gene (H10, from the VHJ558 family), but with enormous diversity in the D region, and one of two germ-line V kappa 1 genes (V kappa 1A, V kappa 1C). These are the same germ-line V-genes used by most primary adult Id+ hybridomas, and the frequency of expression of this germ-line V-gene combination appears equivalent in the neonatal and adult primary repertoires. Therefore, it is clear from this study that as early as day 5, neonatal B cells can use the same germ-line V-genes as adult primary B cells in their Ag-specific repertoire.

Amino Acid Sequence↗
PubMed1989

[The male factor in fertilization in vitro].

Every sperm parameter has an effect on the chances of fertilization. When fertilization has been obtained with a sperm, the cleavage rate is identical regardless of the count, the mobility or the results of the migration test. On the contrary, in case of teratospermia, the cleavage rate of fertilizing sperms is significantly decreased. The rate of pregnancy by transfer is identical with normal sperm and sperm deficiency.

Cleavage Stage, Ovum↗