The influence of epigenetic modifications on reproduction and on the function of male germ cells has been thoroughly demonstrated. In particular, aberrant DNA methylation levels in sperm have been associated with abnormal sperm parameters, lower fertilization rates and impaired embryo development. Recent reports have indicated that human sperm might be epigenetically heterogeneous and that abno...

Sperm dimensions and the question of whether X and Y chromosome-bearing sperm differ in size or shape has been of great interest, especially for the development of alternative methods to sort or classify sperm cells. The aim of the present study was to evaluate possible differences in the shape and size of the sperm head between X and Y chromosome-bearing sperm by atomic force microscopy (AFM)....

Germ cell fate decisions are poorly understood, despite their central role in reproduction. One fundamental question has been whether germ cells are regulated to enter the meiotic cell cycle (i.e., mitosis-meiosis decision) and to be sperm or oocyte (i.e., sperm-oocyte decision) through one or two cell fate choices. If a single decision is used, a male-specific or female-specific meiotic entry ...

Parous ewes were treated orally with medroxyprogesterone acetate (MAP) or melengestrol acetate (MGA), subcutaneously with progesterone, or intra-vaginally with MAP, MGA or progesterone. Treatment was begun on day 8 of an estrous cycle and continued for 17 days. When the ewes were in estrus after progestagen withdrawal, they were inseminated artitlcally and their vulvo-vaginal junctions were lig...

Sperm cells provide essential, if usually diminutive, ingredients to successful sexual reproduction. Despite this conserved function, sperm competition and coevolution with female traits can drive spectacular morphological change in these cells. Here, we characterize four repeated instances of convergent evolution of sperm gigantism in Caenorhabditis nematodes using phylogenetic comparative met...

Metabolic syndrome is a combination of several metabolic diseases such as diabetes mellitus, cardiovascular disease and stroke. The ethanolic extract Moringa Oleifera leaves showed an antioxidant effect in the form significant reduction production intracellular ROS (Reactive Oxygen Species) sperm. This study aims to determine (Moringa Oleifera, Lam.) on level sperm cell maturation testes wistar...

Males among many species, including humans, evaluate cues of sperm competition risk and adjust accordingly their sperm competition tactics. The number of potential sexual rivals can serve as an index of sperm competition risk. Therefore, men may adjust their in-pair copulatory interest in accordance with the presence of sexual rivals. Using self-reports from 45 married men, we test the hypothes...

In flowering plants, the two sperm cells are embedded within the cytoplasm of the growing pollen tube and as such are passively transported to the embryo sac, wherein double fertilization occurs upon their release. Understanding the mechanisms and conditions by which male gametes mature and take part in fertilization are crucial goals in the study of plant reproduction. Studies of gene expressi...

A sperm-driven micromotor is presented as a targeted drug delivery system, which is appealing to potentially treat diseases in the female reproductive tract. This system is demonstrated to be an efficient drug delivery vehicle by first loading a motile sperm cell with an anticancer drug (doxorubicin hydrochloride), guiding it magnetically, to an in vitro cultured tumor spheroid, and finally fre...