In the golden hamster (Mesocricetus auratus), pubertal establishment of spermatogenesis includes a defined period (d 26-30 of life) during which elongation of spermatids is selectively arrested. The resulting appearance of germ cell associations not conforming to stage and the phenomenon of desynchronisation-related germ cell degeneration are analysed both quantitatively and qualitatively by me...

Microinjection is established as the method of choice in the treatment of severe male factor infertility as well as in azoospermic patients. Recent studies have shown that fertilization and cleavage can be achieved by injection of ejaculated as well as testicular elongated spermatids into oocytes. Here we report on the two first pregnancies worldwide resulting from elongated spermatid injection...

Flow cytometry coupled to cell sorting is proposed as a method to isolate round spermatids from testicular biopsies in obstructive azoospermic patients. The cells were separated on the basis of their size and density only. We obtained homogenous populations of alive round spermatids free of lymphocytes and diploid germ cells. The detection of protamine 1 gene (PRM1) and PRM2 expression in the s...

LANCL1 (LanC-like protein 1) is related to the bacterial LanC (lanthionine synthetase C) family, which is involved in the biosynthesis of antimicrobial peptides. Highest expression levels of LANCL1 are found in testes and brain, two organs that exist behind blood-tissue barriers. In the mouse, the establishment of an impermeable blood-testis barrier occurs between day 10-16 post natal (pn). Dif...

Sexual reproduction requires the fusion of two haploid cells to form a diploid zygote. In higher eukaryotes, this implies that specialized diploid cells, the germ cells, reduce their chromosome content during meiosis. A single round of DNA replication followed by two cell divisions characterizes this process, such that a single diploid cell gives rise to four haploid cells. In the first divisio...

We present nine cases of spermatid intracytoplasmic injection for the treatment of non-obstructive azoospermia. In eight cases, no elongated spermatids or spermatozoa were found in previous spermiograms or testicular biopsies. In these patients, treatment was performed using ejaculated (n = 6) and testicular (n = 2) retrieved round spermatids (Sa type). In cases where ejaculated round spermatid...

Fertilization and pregnancy outcomes of 50 round spermatid injection (ROSI) and 20 elongated spermatid injection (ELSI) treatment cycles are related to various characteristics of the cycles, with particular reference to spermatid developmental stage as assessed by using a classification scheme adapted to this purpose. Although this classification includes eight stages, a complete block was most...

Haploid genetics holds great promise for understanding genome evolution and function. Much of the work on haploid genetics has previously been limited to microbes, but possibilities now extend to animal species, including mammals. Whereas haploid animals were described decades ago, only very recent advances in culture techniques have facilitated haploid embryonic stem cell derivation in mammals...

Cells have developed different mechanisms to respond to stress, including the formation of cytoplasmic foci known as stress granules (SGs). SGs are dynamic and formed as a result of stress-induced inhibition of translation. Despite enormous interest in SGs due to their contribution to the pathogenesis of several human diseases, many aspects of SG formation are poorly understood. SGs induced by ...