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This study was carried out to investigate the relationships between computer-aided sperm analysis (CASA), especially the concentration and movement characteristics of progressively motile spermatozoa and fertilization rates in vitro. Semen quality analisys was performed using CASA in 69 IVF-ET cycles with at least 2 oocytes collected. Sperm quality before and after swim-up procedure was compared between 33 cycles with fertilization rate >50%, 23 cycles ≤ 50% and 13 cycles without fertilization. Our study demonstrated that velocity parameters and motility characteristics of sperm from freshly obtained semen and those after swim up procedure correlated with fertilization rates, indicating that these parameters could be good predictors of fertilization outcome.

During healthy pregnancy the dominance of Th2 cytokine production is found in peripheral blood and at maternal-fetal interface. Progesterone and soluble mediator of its function Progesterone Induced Blocking Factor (PIBF) induced Th2 cytokine production in already established Th1 decidual and peripheral blood clones of pregnant women. Th2 cytokine production is accompanied by attenuated NK cell cytotoxicity and are favourable for the gestation. Th1 cytokines support cell mediated immunity and are elevated during pregnancy loss. However, Th1 cytokine IL-15 mRNA was found in normal mouse and human decidua. Decidual NK cells proliferate, accumulate perforin and increase cytotoxicity under IL-15 stimulation in vitro. It is presumed that IL-15 induce proliferation of decidual CD3-CD16-CD56+ NK cells and accumulate cytolytic protein-perforin in their granules in vivo. The aim of this study was to analyse the presence and regulation of IL-15 protein expression in human first trimester pregnancy decidua. Immunohistology of frozen or paraffin embedded first trimester normal human pregnancy decidua was used for IL-15 protein detection. Decidual mononuclear cell, isolated by enzymatic digestion of decidual tissue and gradient density centrifugation were cultured 18 hours in the medium only or in the presence of progesterone (10  g/ml) or PIBF (5  g/ml). Nonadherent cells were removed. Decidual adherent cells (DAC) were collected from the bottom of Petri dishes, stimulated with PMA, Ionomycin and monenzin for further 4 hours, double labelled by anti-IL-15 and anti-HLA-DR antibody and analysed by flow cytometry. Smooth muscle cells of decidual vessels and subdecidual myometrium, glandular cells and cells distributed over the stroll were IL-15+ by immunohistology. Flow cytometry showed 35% of IL-15+ cells in the suspension of DAC, among which 15% were IL-15+/HLA-DR+ (macrophages) and 20% IL-15+/HLA-DR- (stromal) cells. Progesterone and PIBF significantly decreased percentage of IL-15+ cells in the suspension of DAC, due to decrease of IL-15 expression in decidual macrophages. Although progesterone/PIBF in vitro decrease IL-15 expression in decidual HLA-DR+ cells, probably macrophages, there are many IL-15+ cells in first trimester pregnancy decidua characterised by high concentration of progesterone. This results indicate the presence of potent IL-15 stimulator in decidual tissue in vivo.

Axial bathymetry, major/trace elements, and isotopes suggest:that the Pacific-Antarctic Ridge (PAR) between 56 degrees S and 66 degrees S is devoid of any hotspot influence. PAR (56-66 degrees 5) samples have in-average lower Sr-87/Sr-86 and Nd-143/Nd-144 and higher Pb-206/(204)pb than northern Pacific midocean ridge basalts (MORB), and also than MORE from the other oceans. The high variability of Pb isotopic ratios (compared to Sr and Nd) can be due to either a;general high mu (HIMU) (high U/Pb) affinity of the southern Pacific upper mantle or to a mantle event first recorded in time by Pb isotopes. Compiling the results of this study with those from the PAR between 53 degrees S and 57 degrees S gives a continuous view of mantle characteristics from south Pitman Fracture Zone (FZ) to Vacquier FZ, representing about 3000 km of spreading axis. The latitude of Udintsev FZ (56 degrees S) is a limit between, to the north, a domain with large geochemical Variations and, to the south, one with small Variations. The spreading rate has intermediate values (54 mm/yr at 66 degrees S to 74 mm/yr at 56 degrees S) which increase along the PAR, while the axial morphology: changes from valley to dome. The morphological transition is not recorded by the chemical properties of the ridge basalts nor by the inferred mantle temperature which displays few variations (30-40 degrees C) along the PAR. Contrary to what is observed along the South-East Indian Ridge, PAR morphology appears to be controlled more by spreading rate rather than by mantle temperature. Much of the major and trace element variability results from segmentation control on the shallowest thermal structure of the mantle. The cold edge of a fracture zone seems to be more efficient when occurring in an axial dome context.:It is expressed as an increase of the magnitude of the Transform Fault Effect along the valley-dome transition, resulting in a clear increase of trace element ratio variability (such as Nb/Zr). There is no strong evidence for the previously proposed southwestward asthenospheric flow in the area. However, this flow model could explain the intrasegment asymmetric patterns.

The Pacific-Antarctic Ridge (PAR) between 56 and 66°S is far removed from any hotspot influence. The small geochemical variations observed along the ridge can be interpreted as being the result of cold edge effect caused by fracture zones. This effect seems to increase during the morphological transition from valley to dome, leading to an increase of trace element variability. The ridge morphological transition is not controlled by the mantle temperature., La dorsale Pacifique-Antarctique entre 56 et 66°S est éloignée de l'influence de tout point chaud. Les faibles variations géochimiques observées le long de l'axe peuvent être interprétées comme résultant de l'effet froid des zones de fracture. Cet effet semble croître lors de la transition morphologique vallée-dôme, conduisant à une augmentation de la variabilité chimique. La transition de morphologie axiale n'est pas contrôlée par la température du manteau.