Methylation analysis of histone H4K12ac-associated promoters in sperm of healthy donors and subfertile patients.

Background: Histone to protamine exchange and the hyperacetylation of the remaining histones are hallmarks of spermiogenesis. Acetylation of histone H4 at lysine 12 (H4K12ac) was observed prior to full decondensation of sperm chromatin after fertilization suggesting an important role for the regulation of gene expression in early embryogenesis. Similarly, DNA methylation may contribute to gene silencing of several developmentally important genes.

Influence of motility and vitality in intracytoplasmic sperm injection with ejaculated and testicular sperm.

The vitality of spermatozoa used for intracytoplasmic sperm injection (ICSI) is a crucial factor for fertilization, establishment and outcome of a pregnancy in assisted reproductive technique cycles. The sperm origin may also be a limiting factor, although little is known about this issue. It is known that the motility of injected spermatozoa and their origin from ejaculate or testicular biopsies are important predictors in terms of fertilization, pregnancy and birth rates.

Effect of factor XIII on endothelial barrier function.

The effect of factor XIII on endothelial barrier function was studied in a model of cultured monolayers of porcine aortic endothelial cells and saline-perfused rat hearts. The thrombin-activated plasma factor XIII (1 U/ml) reduced albumin permeability of endothelial monolayers within 20 min by 30 +/- 7% (basal value of 5.9 +/- 0.