Polyspermy is pathological in mammals (Austin & Walton, i960), but is uncommon because mechanisms exist which prevent its occurrence. In the sheep, cow, pig and other species, after penetration by the first spermatozoon, the zona pellucida undergoes a change, the 'zona reaction', which bars further spermatozoa from passing through the zona, but still allows them to enter it. Unlike the eggs of ...

The role in early development of proteins secreted by oviduct epithelial cells has been investigated. Secreted proteins devoid of serum contamination have been produced by the surgical removal and immediate incubation of oviduct cells in [35S]methionine-containing medium. After electrophoretic separation, secreted polypeptides could be divided into those that were secreted uniformly throughout ...

BACKGROUND/AIMS To observe the effects of vitrification on spindle, zona pellucida, embryonic aneuploidy and DNA injury in in vivo-maruted, in vitro-mature and immature human oocytes. METHODS Between January 2009 and February 2015, 223 immature oocytes from 450 infertile patients, and 31 in vivo-mature oocytes from 3 infertile couples were collected. Of the 223 immature oocytes, 113 were used...

Zona pellucida (ZP) is an extracellular matrix surrounding and protecting mammalian and fish oocytes, which is responsible for sperm binding. Mammalian ZP consists of three to four glycoproteins, called ZP1, ZP2, ZP3, ZP4. These proteins polymerize into long interconnected filaments, through a common structural unit, known as the ZP domain, which consists of two domains, ZP-N and ZP-C. ZP is re...

Seyed Mohammad Ali Shariatzadeh & Zahra Alizadeh Department of Biology, Faculty of Sciences, Arak University, Arak, Iran Correspondent author: Seyed Mohammad Ali Shariatzadeh, [email protected] Abstract. Silver nanoparticles (Ag NPs) can affect female fertility because they can cause toxicity in the ovaries. The aim of this study is to see if Spirulina platensis (SP) can protect m...

BACKGROUND Spermatogenesis is a complex cellular developmental process which involves diverse families of genes. The Xlr (X-linked, lymphocyte regulated) family includes multiple members, only a few of which have reported functions in meiosis, post-meiotic maturation, and fertilization of germ cells. Slx-like1 (Slxl1) is a member of the Xlr family, whose expression and function in spermatogenes...

BACKGROUND Zona pellucida opening for blastomere removal can be done by mechanical or chemical means, or by laser. So far, only limited data on the use of laser systems for zona drilling in cases of PGD are available. METHODS Results of embryo biopsy and outcome of PGD in two periods were compared. In the first period, acid Tyrode medium was used for zona drilling. In the second period, zona ...

The rapid evolution of proteins involved in reproduction has been documented in several animal taxa. This is thought to be the result of forces involved in sexual selection and is expected to be particularly strong in promiscuous mating systems. In this study, a range of cetacean species were used to analyze the patterns of evolution in 2 reproductive proteins involved in fertilization: the zon...