Evaluation of live birth rates and perinatal outcomes following two sequential vitrification/warming events at the zygote and blastocyst stages.

Purpose: To study the outcome of sequential cryopreservation-thawing of zygotes followed by the cryopreservation-thawing of blastocysts in the course of an IVF treatment on live birth rate and neonatal parameters.

Methods: Single center, retrospective chart review for the time period of 2015-2020. Clinical and perinatal outcomes were compared between frozen embryo transfer cycles utilizing twice-cryopreserved (n = 182) vs.

[Fertility preservation in female cancer patients.].

The incidence of cancer increases with age and as family planning is being delayed, there is a growing number of cancer patients whose fertility may be affected by oncological treatments. International guidelines recommend that all reproductive age cancer patients, including adolescent patients, should be referred for fertility preservation consultation, and if necessary, fertility preservation procedures should be performed. Fertility preservation enables cancer survivors to offer a chance for biological parenthood after recovery.

[Fertility preservation in cancer patients].

Introduction: Fertility preservation or oncofertility is a relatively new interdisciplinary field dealing with the preservation of female and male reproductive functions before the administration of gonadotoxic therapy. Despite recommendations from different international scientific bodies, Hungary still does not have a national fertility preservation network, patient referral is unorganised. Objective: As the first step towards establishing a national fertility preservation program, a study was designed to evaluate the Hungarian oncologists' knowledge, attitudes and practice in the field of oncofertility.

[Unaffected child born following preimplantation genetic diagnosis with karyomapping].

Preimplantation genetic diagnosis for single gene defects is a well established method in assisted reproductive technologies. Karyomapping is a genome wide parental haplotyping using a high density single nucleotide polymorphism array that allows the diagnosis of any single gene defects. A couple with an affected child with primary congenital glaucoma attended at our clinic.

Abnormal methylation of the promoter of CREM is broadly associated with male factor infertility and poor sperm quality but is improved in sperm selected by density gradient centrifugation.

Objective: To evaluate the methylation status of the promoter of CREM in patients with an abnormal protamine 1/protamine 2 (P1/P2) ratio or oligozoospermia. The effects of density gradient centrifugation and aging of males on CREM promoter methylation were also investigated.

Design: Experimental research study.

The clinical utility of the protamine 1/protamine 2 ratio in sperm.

During spermiogenesis, human sperm undergo a dramatic reorganization of the chromatin in which canonical histones are replaced by two types of protamines, protamine 1 (P1) and protamine (P2). P1 and P2 are expressed approximately at a 1:1 ratio in healthy men. Alteration of this ratio is associated with male infertility.

Analysis of the methylation pattern of six gene promoters in sperm of men with abnormal protamination.

It has recently been shown that alteration of the methylation pattern of imprinted genes is associated with different types of male infertility. The objective of our study was to investigate the methylation pattern of selected gene promoters in sperm of patients with abnormal protamine replacement. The promoters of OCT4, SOX2, NANOG, HOXC11, miR-17 and CREM were analyzed using bisulfite sequencing and the percentage of DNA methylation was compared between patients with an abnormal protamine 1/protamine 2 (P1/P2) ratio and normozoospermic controls.

The marmoset and cotton rat as animal models for the study of sperm chromatin packaging.

In the human, canonical histones are largely replaced by protamine 1 (P1) and protamine 2 (P2) during late spermatogenesis. Recent studies have demonstrated that abnormal replacement of the histones is associated with severe male infertility and has profound implications for early embryogenesis. In this review the hispid cotton rat and the common marmoset are evaluated as animal models for the study of chromatin packaging in sperm.

Comparison of 5% and ambient oxygen during days 3-5 of in vitro culture of human embryos.

Objective: To compare the effect of two oxygen concentrations used during days 3-5 of human embryo culture on embryo quality and pregnancy outcome.

Design: Retrospective analysis of the use of two culture conditions.

Setting: University-based infertility clinic.

Incidence of apoptosis in parthenogenetic porcine embryos generated by using protein kinase or protein synthesis inhibitors.

In mammals, embryonic development can be artificially initiated by activating the oocyte using a number of methods. In the present research, we investigated whether butyrolactone I and cycloheximide, two chemicals frequently used in combined oocyte activation protocols, have any detrimental effect on programmed cell death in the developing porcine embryo. Parthenogenetic porcine blastocysts were generated by the following methods: (1) electroporation followed by blocking the activity of specific protein kinases with butyrolactone I; (2) electroporation followed by inhibition of protein synthesis using cycloheximide; and (3) electroporation only (control).

Paternal effects on early embryogenesis.

Historically, less attention has been paid to paternal effects on early embryogenesis than maternal effects. However, it is now apparent that certain male factor infertility phenotypes are associated with increased DNA fragmentation and/or chromosome aneuploidies that may compromise early embryonic development. In addition, there is a growing body of evidence that the fertilizing sperm has more function than just carrying an intact, haploid genome.

Effects of activation methods and culture conditions on development of parthenogenetic porcine embryos.

The effects of different activation methods and culture conditions on early development of porcine parthenotes were examined. Three different activation methods were tested: (1) electroporation; (2) electroporation followed by incubation in the presence of butyrolactone I, an inhibitor of cdc2 and cdk2 kinases; and (3) electroporation followed by a treatment with cycloheximide, a blocker of protein synthesis. The activated oocytes were cultured in two different media, NCSU-23 and PZM-3 under 5% CO2 in air.

Experiences in deer sperm cryopreservation under practical conditions--a pilot study.

The genetic potential of the red and fallow deer populations in Hungary is well known. Conserving the variability in this excellent genetic material for game preservation is one of our most important task. The aim of the present pilot study was to test the logistical steps of a sperm processing and storing system in which deer sperm can be stored at a level that meets quality standards accepted for domestic animals.