Evaluation of fragmented embryos implantation potential using time-lapse technology.

Aim: To examine the implantation potential of fragmented embryos that underwent morphokinetic evaluation in a time-lapse incubator.

Methods: A retrospective study analyzing 4210 Day 5 embryos which were incubated in a time-lapse incubator, between 2013 and 2019. Embryos with more than 5% fragmentation (379 embryos) were included in the study.

Improving embryo selection by the development of a laboratory-adapted time-lapse model.

Objective: To study whether a powerful, in-house, embryo-selection model can be developed for a specific in vitro fertilization (IVF) laboratory where embryos were already selected for transfer using general models.

Design: In total, 12,944 fertilized oocytes were incubated in an EmbryoScope (Vitrolife, Göteborg, Sweden) at our laboratory. Embryos were selected for transfer or freezing using general models.

Comparison of day 2 and overnight day 3 frozen embryo transfers: A prospective randomized controlled trial.

In certain patients cleavage stage embryos may be preferred. The relationship between an additional day in culture and pregnancy outcomes is not well established. We aimed to compare outcomes of day 2 versus overnight day 3 frozen embryo transfer (FET).

Live Birth from the Transfer of a Severely Fragmented Embryo Observed by Morphokinetics.

We report a live birth from a heavily fragmented embryo which continued cleavage to a fully expanded blastocyst. A 32-year-old patient underwent 2 IVF cycles without achieving pregnancy. In the first cycle, 2 embryos with fragmentation were transferred; in the second, all embryos were fragmented and no embryo transfer was performed.

A20 inhibits both the degradation and limited processing of the NF-κB p105 precursor: A novel additional layer to its regulator role.

p105 plays dual roles in NF-κB signaling: it generates the active subunit p50 and in its precursor form inhibits NF-κB activation. p105 processing occurs under basal conditions and increases following signaling. IκB kinase β (IKKβ) mediates phosphorylation at the C-terminal domain of p105, leads to accelerated processing and degradation of the precursor.

The testis-specific USP26 is a deubiquitinating enzyme of the ubiquitin ligase Mdm2.

Murine double minute-2 (Mdm2) is one of the E3-ligases of the androgen receptor besides being the major regulator of the p53 tumor suppressor. The testis-specific USP26 was demonstrated to regulate the androgen receptor. In the present study we examined possible association between the deubiquitinating enzyme - ubiquitin specific protease 26 (USP26), and the oncoprotein E3 ligase - (Mdm-2).

Oxidative markers in cryopreservation medium from frozen-thawed embryos: a possible tool for improved embryo selection in in vitro fertilization?

Purpose: The present study evaluated the association between oxidative parameters in embryo cryopreservation medium and laboratory and clinical outcomes.

Methods: This prospective laboratory study was conducted in an IVF unit in a university-affiliated hospital with 91 IVF patients undergoing a frozen-thawed embryo transfer cycle. Following thawing, 50 μL of embryo cryopreservation medium was retrieved from each cryotube and tested by the thermochemiluminescence (TCL) assay.

p27 and its ubiquitin ligase Skp2 expression in endometrium of IVF patients with repeated hormonal stimulation.

This preliminary study examined a possible effect of long duration repeated hormonal stimulation on the endometrium using a molecular tool. The expression of the hormone stimulated, cell cycle regulators, p27 and its ligase S-phase kinase-interacting protein2 (Skp2), were assessed in 46 endometrial samples of patients who underwent repeated IVF cycles (3-21). Skp2 protein is usually undetectable in normal tissue and can be demonstrated only in rapidly dividing cells.

[CHALLENGING THE OPTIMAL NUMBER OF RETRIEVED OOCYTES AND ITS IMPACT ON PREGNANCY AND LIVE BIRTH RATES IN IVF/ICSI CYCLES].

Introduction: Large numbers of retrieved oocytes are associated with higher chances of having cryopreservation of embryos. However, the process entailed exposes women to increased risk for ovarian hyperstimulation syndrome. Furthermore, mild ovary stimulation protocols are more patient-friendly and with less adverse effects.

Habits of cell phone usage and sperm quality - does it warrant attention?

Male infertility constitutes 30-40% of all infertility cases. Some studies have shown a continuous decline in semen quality since the beginning of the 20th century. One postulated contributing factor is radio frequency electromagnetic radiation emitted from cell phones.

[Oxidation and female reproduction: the good, the bad and what's between].

Reactive oxygen and nitrogen species constitute an inseparable part of aerobic life on earth. They have been known to science for about 90 years, but only during the last 50 years research in this field has expanded. Initially, scientists focused on the free radicals-induced damage to biological systems.

Oxidative parameters of embryo culture media may predict treatment outcome in in vitro fertilization: a novel applicable tool for improving embryo selection.

Objective: To examine whether the oxidative status of an individual embryo before transfer may predict chances of implantation.

Design: A prospective laboratory study.

Setting: An IVF unit in a university-affiliated hospital.

ABIN-1 negatively regulates NF-kappaB by inhibiting processing of the p105 precursor.

p105 plays dual roles in NF-kappaB signaling: in its precursor form it inhibits NF-kappaB activation, but limited processing by the ubiquitin system generates the p50 active subunit of the transcription factor. Here we show that ABIN-1, an A20-binding protein that is also known to attenuate NF-kappaB activation, inhibits p105 processing. p105 and ABIN-1 physically interact with one another, but the binding is not necessary for inhibition of processing.

Expression of the ubiquitin ligase subunit cyclin kinase subunit 1 and its relationship to S-phase kinase protein 2 and p27Kip1 in prostate cancer.

Purpose: Loss of the cell cycle inhibitory protein p27Kip1 in cancer is associated with tumor aggressiveness and poor prognosis in the prostate. The decrease in p27(Kip1) results from increased proteasome dependent degradation, which is mediated by its specific ubiquitin ligase subunits S-phase kinase protein 2 and cyclin dependent kinase subunit 1. S-phase kinase protein 2 was found to be over expressed in aggressive prostate cancers but to our knowledge the role of cyclin dependent kinase subunit 1 in these cancers is unknown.

Two distinct ubiquitin-dependent mechanisms are involved in NF-kappaB p105 proteolysis.

Generation of the p50 subunit of NF-kappaB is a rare case in which the ubiquitin system processes a longer precursor, p105, into a shorter active subunit: in the vast majority of cases, the target protein is completely degraded. The mechanisms involved in this process have remained elusive. It appears that a Gly rich region (GRR) in the middle of the molecule serves as a "processing stop signal", though under certain conditions, such as after stimulation, p105 can be completely degraded.

Oxidative stress indices in follicular fluid as measured by the thermochemiluminescence assay correlate with outcome parameters in in vitro fertilization.

Objective: To evaluate oxidative stress indices in follicular fluid (FF) by a novel thermochemiluminescence (TCL) assay and investigate the correlation between TCL and i.v.f.

Early embryo-endometrial signaling modulates the regulation of matrix metalloproteinase-3.

Objective: To examine matrix metalloproteinase-3 (MMP-3) expression in human stromal cell culture after P stimulation and the effect of conditioned medium from human embryo-epithelial cells coculture on its expression and activity.

Design: Metabolic and endocrine studies on human tissue.

Setting: In vitro fertilization (i.

Decreased level of the cell cycle regulator p27 and increased level of its ubiquitin ligase Skp2 in endometrial carcinoma but not in normal secretory or in hyperstimulated endometrium.

p27 is a cyclin-dependent kinase (CDK) inhibitor whose specific late G(1) destruction allows progression of the cell across the G(1)/S boundary. The protein is ubiquitinated by S-phase kinase-interacting protein-2 (Skp2) following its specific phosphorylation, and is subsequently degraded by the 26s proteasome. There is a direct relationship between low level of p27 and rapid proliferation occurring in several benign states and in many malignancies.

Oxidative stress indices in seminal plasma, as measured by the thermochemiluminescence assay, correlate with sperm parameters.

Objective: To examine the effect of oxidation of proteins and lipids, as measured by a novel thermochemiluminescence (TCL) analyzer, and to evaluate the correlation between TCL indices in seminal plasma and sperm parameters.

Design: Experimental and prospective clinical studies.

Setting: An infertility unit.

Analyzing factors affecting the success rate of frozen-thawed embryos.

Purpose: In recent years the infertile population applying for IVF treatments was changed and so the indications for performing intracellular sperm injection (ICSI). The aim of this study was to analyze predicting factors of our thawing cycles.

Methods: From December 1998 to July 2001, 440 consecutive thawing cycles were performed.

A prospective randomized controlled study of the effect of short coincubation of gametes during insemination on zona pellucida thickness.

A prospective, randomized study was conducted to evaluate the thickness, of zona pellucida (ZP) after brief or standard exposure of human oocytes to spermatozoa, and to determine the correlation between ZP thickness, fertilization rate and embryo quality. The mean ZP thickness 48 h after insemination was found to be significantly less in fertilized oocytes than in non-fertilized oocytes in all treated groups (13.72 +/- 3.

The impact of cigarette smoking on zona pellucida thickness of oocytes and embryos prior to transfer into the uterine cavity.

Background: Smoking has been reported to promote infertility. The zona pellucida plays an important role in fertilization and implantation. We report, for the first time, the effect of cigarette smoking on zona pellucida thickness of oocytes and embryos as one of the factors that may interfere with fertility.

The impact of early testicular sperm extraction or cryopreservation on the outcome of intracytoplasmic sperm injection--a randomized controlled study.

Purpose: To compare the outcome of sperm extraction 24 h before ovum pickup and on the day of oocyte retrieval.

Methods: A controlled study was performed to compare the outcome of 90 sperm extractions and in vitro sperm injection cycles performed in 54 patients.

Results: Available fresh sperm for the sperm injection procedure and cryopreservation obtained on the day of ovum pickup were similar to sperm collected 1 day before (33.

Inverse relationship between Skp2 ubiquitin ligase and the cyclin dependent kinase inhibitor p27Kip1 in prostate cancer.

Purpose: Prostate carcinomas show a low level of the cell cycle inhibitor p27, which correlates with tumor aggressiveness. In tumors p27 is of the WT species and its deregulation is due to aberrant ubiquitin mediated degradation. The p27 is degraded following phosphorylation and subsequent recognition by SCFSkp2 ubiquitin ligase.