Current methods of analyzing sperm chromatin competency overlook the inner sperm compartment which is inaccessible to probes and reagents. By breaking the molecular protamine disulfide bridges, the DNA toroids are exposed to integrity analysis. The aim was to develop a simple nuclear toroid test and determine its association with fertilization, pregnancy, and miscarriage. The approach involved ...

introduction: during spermiogendsis, sperm chromatin histones are replaced by protamine. after fertilization, the sprem nucleus is decondenced by glutathione (gsh). in this survey, we study the effect of various concentrations of gsh on human in vitro sperm decondensation. material and methods: after preparation and analysis of semen samples, sperm pellet was washed by ham's f-10 medium twice a...

A growing number of genes involved in sex and reproduction have been demonstrated to be rapidly evolving. Here, we show that genes expressed solely in spermatozoa represent a highly diverged subset among mouse and human tissue-specific orthologs. The average rate of nonsynonymous substitutions per site (K(a)) is significantly higher in sperm proteins (mean K(a) = 0.18; N = 35) than in proteins ...

An adaptation of the Feulgen procedure to visualise DNA at the ultrastructural level, using osmium ammine instead of Schiff reagent, was applied to ultrathin sections of rabbit epididymal spermatozoa, known to display increasing chromatin compaction as they progress through the epididymis. In contrast with the somatic cell nuclei of the epididymal epithelium, which display classical staining, t...

DNA stability and thiol-disulphide status of rat sperm nuclei was observed in vivo during maturation in the epididymis and penetration of oocytes. When spermatids and spermatozoa were stained with acridine orange after fixation with acetic alcohol, the red/green fluorescence ratio observed under a confocal microscope was not different between spermatids (3.81 +/- 0.16) and testicular spermatozo...

The scope of paternal contributions during early embryonic development has long been considered limited. Dramatic changes in chromatin structure throughout spermatogenesis have been thought to leave the sperm void of complex layers of epigenetic regulation over the DNA blueprint, thus leaving the balance of that regulation to the oocyte. However, recent work in the fields of epigenetics and mal...

sperm chromatin integrity has been being recognized as an important factor in male fertility. during normal fertilization, high quality sperm with intact chromatin are selected through natural selection in journey from vagina to fallopian tube. however, using assisted reproductive techniques, particularly icsi, the natural selection is bypassed. therefore sperm with dna breakage have the opport...

Nearly 2 m of DNA is so tightly packaged that it fits neatly within the nucleus of each cell of our body. As if this was not mind-blowing enough, the problem is intensified in the male germline, as the nucleus of a sperm cell is about 6 times smaller than that of a somatic cell. Sperm are highly specialized cells charged with the sole responsibility of delivering the paternal genome to offsprin...

Objective The aim of this study was to investigate the effects of curcumin on epididymal sperm parameters in adult male Navel Medical Research Institute (NMRI) mice exposed to sodium arsenite. MaterialsAndMethods In this experimental study, we divided the animals into four groups: control, sodium arsenite (5 mg/kg), curcumin (100 mg/kg) and curcumin+sodium arsenite. Exposures were performed by ...

In typical somatic cells, DNA is tightly organized by histones that are necessary for its proper packaging into the nucleus. In sexually-reproducing animals, the haploid product of male meiosis must be further condensed to fit within sperm heads, thus requiring an even greater degree of packaging. This is accomplished in most organisms by replacing histones with protamines, which allows DNA to ...