Impact of phase transition on the mouse oocyte spindle during vitrification.

During vitrification, the glass-like solidification is the phase-transition process from liquid to solid. Phase transition is one of the major factors suspected to affect the physiology of the oocyte, such as the structure of the meiotic spindle. Therefore, it is very important to investigate the systematic and morphological alterations of the metaphase-II spindle and chromosome arrangement during complete course of a vitrification and warming process.

The efficacy and safety of human oocyte vitrification.

Vitrification is now a widely applied and highly successful approach for cryopreservation in reproductive biology. Rapidly increasing data prove that it is also a highly efficient technique for low-temperature storage of human oocytes. The latest approaches with appropriately selected cryoprotectants, tools and techniques, and properly adjusted parameters allow close to 100% morphological survival rates, and in vitro embryo development, as well pregnancy and implantation rates, comparable with those achieved with fresh oocytes.

The oocyte spindle is preserved by 1,2-propanediol during slow freezing.

Objective: To investigate the specific changes in oocyte spindle subjected to severe challenges of low temperature, as well as to examine the effect of cryoprotectants in preserving oocyte spindle during cryopreservation.

Design: In vitro experimental study.

Setting: Academic research laboratory.

Human oocyte vitrification: in-vivo and in-vitro maturation outcomes.

This study aimed to evaluate oocyte vitrification efficiency using in-vivo matured (IVO) versus rescued in-vitro matured (IVM) oocytes. The results show that oocyte survival (85% versus 81%), fertilization (86% versus 76%) and cleavage rate (98% versus 89%) was not significantly different in IVO oocytes compared with rescued IVM sibling oocytes. The fertilized oocytes from IVO and IVM groups were cultured to blastocyst stage; however, embryo development was significantly reduced in the rescued IVM group (72% versus 15%).

Effect of denuding on polar body position in in-vitro matured oocytes.

The aim of this study was to determine whether the denuding procedure causes the polar body to move within the perivitelline space. Only those patients undergoing IVF who had unused in-vitro matured (IVM) oocytes were included in this study. IVM oocytes were initially viewed under a non-invasive, polarized light microscope.

Clinical evaluation of the efficiency of an oocyte donation program using egg cryo-banking.

Objective: To evaluate the efficiency of oocyte donation cycles using egg "cryo-banking."

Design: Study conditions for vitrified/warmed oocytes for 20 non-autologous recipients (from 10 donors) were set prospectively, and outcomes of it were later compared retrospectively to nine fresh donations cycles.

Setting: Private assisted reproductive technology program.

Comparison of ICSI and conventional IVF in patients with increased oocyte immaturity.

Using sibling oocytes, the objective of this study was to compare the intracytoplasmic sperm injection (ICSI) fertilization rates to those achieved with conventional IVF in patients with high rates of oocyte immaturity. This study was observational in nature, and included 91 patients who were treated using split insemination techniques. The fertilization rates for the ICSI group and the IVF group were 41.

Two successful pregnancies obtained following oocyte vitrification and embryo re-vitrification.

Recent clinical reports not only show that cryopreserved embryos can be successfully used for human fertility treatment, but also that cryopreserved oocytes may be used successfully as an adjunct to human assisted reproductive technologies. Vitrification is known to establish a glass-like solid state during the cooling process. The high concentration of cryoprotectants and an extremely rapid rate of cooling are responsible for the formation of the solid state, and also prevent formation of intracellular ice crystals.

Lysed cell removal promotes frozen-thawed embryo development.

Objective: To develop a mouse model to investigate the possible causes for increased success rates when lysed cells are removed from thawed embryos.

Design: Experimental study.

Setting: Clinical IVF laboratory.

Influence of the preimplantation embryo development (Ped) gene on embryonic platelet-activating factor (PAF) levels.

Purpose: A major gene responsible for the control of preimplantation cleavage rate is the Ped gene, the product of which is the Qa-2 protein. Fast, but not slow developing mouse embryos express the Qa-2 protein. Platelet-activating factor (PAF) is a novel and potent signaling phospholipid that has unique pleiotropic properties in addition to platelet activation.

Comparison of laser-assisted hatching and acidified Tyrode's hatching by evaluation of blastocyst development rates in sibling embryos: a prospective randomized trial.

Objective: To assess two zona drilling methods in terms of blastocyst development rates using sister embryos.

Design: Prospective, randomized study. Sister embryos of 14 patients were randomly assigned on day 3 to acidified Tyrode's zona drilling or to laser zona drilling.

Platelet-activating factor acetylhydrolase activity affects sperm motility and serves as a decapacitation factor.

Objective: To determine the relationship between platelet-activating factor acetylhydrolase (PAFah) content in semen and sperm motility.

Design: The PAFah levels in semen were measured and correlated with sperm motility.

Setting: Clinical laboratory in a private assistant reproductive technology clinic.

Effect of reduced oocyte aging on the outcome of rescue intracytoplasmic sperm injection.

Objective: To evaluate the results of a novel protocol that allows to rescue IVF unfertilized oocytes by intracytoplasmic sperm injection (ICSI).

Design: Prospective clinical trial.

Setting: Private reproductive medical center.

Removal of lysed blastomeres from frozen-thawed embryos improves implantation and pregnancy rates in frozen embryo transfer cycles.

Objective: To evaluate the effect of degenerated (lysed) blastomere removal on implantation and pregnancy rates in cleavage-stage cryo-embryo transfer (ET) cycles.

Design: Randomized clinical trial.

Setting: Private reproductive medical center.

Impact of body mass index values on sperm quantity and quality.

Body mass index (BMI) has been demonstrated to affect female fertility; however, little information is available on the impact of BMI on male fertility or semen parameters. Therefore, the study objective was to determine the relationship between BMI and semen parameters, including sperm chromatin integrity. We analyzed data on semen samples from 520 men who were grouped based upon calculated BMI values (normal, 20-24 kg/m(2); overweight, 25-30 kg/m(2); obese, >30 kg/m(2)).

High seminal platelet-activating factor acetylhydrolase activity in men with spinal cord injury.

Spinal cord injury (SCI) causes male infertility, with low sperm motility the major long-term cause. It has been suggested in previous studies that some seminal components may be responsible for the pathological asthenozoospermia. It is hypothesized that platelet-activating factor (PAF) acetylhydrolase (PAFah), which originates in the epididymis and other accessory sexual glands, may be a causative factor.

The significance of platelet-activating factor and fertility in the male primate: a review.

Since its discovery nearly 30 years ago platelet-activating factor (PAF) has emerged as one of the more important lipid mediators known. PAF (1-O-alkyl-2-O-acetyl-sn-glycero-3-phosphorylcholine) exists endogenously as a mixture of molecular species with structural variants of the alkyl moiety. PAF is a novel potent signaling phospholipid that has unique pleiotropic biological properties in addition to platelet activation.

Exposure of preimplantation embryos to platelet-activating factor increases birth rate.

Problem: Platelet-activating factor (PAF) plays a significant role in fertility. Preimplantation stage embryos produce PAF (ePAF) which is required for development. PAF's mechanism of action is receptor-mediated and its presence has been reported in the developing mouse and human embryo.

Platelet-activating factor significantly enhances intrauterine insemination pregnancy rates in non-male factor infertility.

Objective: To determine the efficacy of treating semen specimens with platelet-activating factor (PAF) before IUI.

Design: Prospective randomized double-blinded study of PAF treatment of sperm for patients with a history of infertility undergoing IUI.

Setting: Private infertility center.