Prevention of polyspermic fertilization in sea urchins (Jaffe, 1976, Nature (Lond.). 261:68-71) and the worm Urechis (Gould-Somero, Jaffe, and Holland, 1979, J. Cell Biol. 82:426-440) involves an electrically mediated fast block. The fertilizing sperm causes a positive shift in the egg's membrane potential; this fertilization potential prevents additional sperm entries. Since in Urechis the egg...

The eccentric shift of the sea-urchin egg within the fertilization membrane under an electric field was analysed by measuring the electrophoretic mobility of the isolated fertilization membrane and that of the egg deprived of the fertilization membrane. In addition, the migration speed of the egg proper was measured within the fertilization membrane under the conditions that: either (1) the mov...

background: determination of oocyte and embryo quality are one of the most important goals in ivf. anti-mullerian hormone (amh) is secreted by the ovarian granulosa cells into blood flow and follicular fluid. follicular fluid anti-mullerian hormone level is probably a marker of activity of granulose cells. objective: to evaluate whether high level of follicular fluid anti-mullerian hormone leve...

Background: Failed fertilization post ICSI has been mainly attributed to the sperm’s inability to induce oocyte activation. Phospholipase C Zeta (PLCζ) is considered to be a primary factor for the induction of oocyte activation. The aim of this study was to quantitatively assess the expression of PLCζ in globozoospermic or individuals with previous low or failed fertilization in comparison to f...

To investigate the mechanisms that account for the voltage dependence of fertilization and provide an electrical block to polyspermy, we studied cross-fertilizations between three species of amphibians having different degrees of voltage dependence. Anurans, such as the toad Bufo japonicus, as well as the primitive urodele Hynobius nebulosus, have voltage-dependent fertilization; other urodeles...

the use of vermicompost and fall fertilization in soilless culture on strawberry cv. camarosa quality characteristics was evaluated in a factorial based on completely randomized design pot experiment with 5 replicates. experimental treatments were four chemical fertilization timings (no fertilizer, using fertilizer at fall, spring, fall + spring) and three levels of vermicompost (10, 20 and 40%...

Fertilization in Fucus serratus is directly proportional to the number of sperm added, saturating at approximately 250 sperm per egg with an apparent Km of 120 sperm per egg. The effect of a range of lectins on fertilization has been tested. Preincubation of gametes with Con A and fucose-binding protein (FBP) inhibited fertilization. At low concentrations this was by specifically binding to egg...

Mammalian fertilization comprises sperm migration through the female reproductive tract, biochemical and morphological changes to sperm, and sperm-egg interaction in the oviduct. Recent gene knockout approaches in mice have revealed that many factors previously considered important for fertilization are largely dispensable, or if they are essential, they have an unexpected function. These resul...

we examined the demographic characteristics of couples, ovarian response and sperm quality to determine the predictors of clinical fertilization in ivf cycles. a descriptive and analytic study was conducted using data and biologic specimens obtained fatemeh-alzahra of babol infertility center from 2004 to 2005. only data from 315 women who had medical indication for conventional ivf treatment w...

Background: Although in vitro fertilization (IVF) has been found to bypass the inhibitory effect of high levels of antisperm antibodies on sperm motility, fertilization rates are reduced in approximately 40% of the attempts. In this study, we investigated the relationship between antisperm antibodies measured by the direct mixed agglutination reaction (MAR) and the fertilization rate in inferti...