Many investigators maintain that spermatozoa that have initiated the acrosome reaction (AR) before reaching the surface of the egg's zona pellucida (ZP) are unable to bind and penetrate the ZP. A recent study has revealed that most fertilizing mouse spermatozoa initiate the AR before contacting the ZP. We found that acrosome-reacted spermatozoa collected from the perivitelline space of Cd9-null...

BACKGROUND Sperm DNA damage (fragmentation) is a recently discovered cause of male infertility for which no efficient treatment has yet been found. Previous findings have suggested that clinically relevant sperm DNA damage may occur at the post-testicular level. This study was undertaken to assess the clinical usefulness of ICSI with testicular spermatozoa in this indication. METHODS The perc...

In mice and humans, a normal offspring can be obtained by injecting a single spermatozoon into an oocyte, the process called intracytoplasmic sperm injection (ICSI). When three or more mouse spermatozoa with intact acrosomes were injected into individual mouse oocytes, an increasing proportion of oocytes became deformed and lysed. Oocytes did not deform and lyse when acrosome-less spermatozoa w...

OBJECTIVE To evaluate the role of hyaluronic acid (HA) for sperm selection before intracytoplasmic sperm injection (ICSI). DESIGN Three prospective studies. SETTING Private assisted reproduction center in Italy. PATIENT(S) Study 1: 20 men. Study 2: 15 men. Study 3: 206 couples treated with ICSI on a limited number of oocytes per patient (1-3) in accordance with Italian IVF law. INTERVEN...

The aim of this study was to assess two models of sperm collection on the quality and fertility of thawed spermatozoa from Black Manchega rams, a threatened breed. Sperm samples were collected by electroejaculation and postmortem from each male. Samples were diluted with Biladyl and frozen. Motility (subjective and objective by means of computer-assisted semen analysis), membrane integrity, and...

Previously, a relationship has been found between diminished cellular maturity of human spermatozoa and low-level expression of the testis-specific chaperone protein, HspA2. Because HspA2 is a component of the synaptonemal complex in rodents, and assuming that this is also the case in men, it was postulated that the frequency of chromosomal aneuploidies would be higher in immature versus mature...

Electron microscopic examination of the spermatozoa from a man suffering from asthenozoospermia (poor or low sperm motility) showed that approximately 92% of the sperm flagella lacked central pair microtubules but possessed dynein arms and radial spokes while a small percentage of the spermatozoa had complete flagella. The characteristics of the motor apparatus of the spermatozoa and the effect...

This study compared three cryopreservation protocols on sperm functions, IVF outcomes, and embryo development. Epididymal spermatozoa cryopreserved using slow-cooling (18% w/v raffinose, RS-C) were compared with spermatozoa vitrified using 0.25 M sucrose (SV) or 18% w/v raffinose (RV). The motility, vitality, and DNA damage (TUNEL assay) of fresh control (FC) spermatozoa were compared with post...

Improved sperm selection techniques are needed to increase the efficiency of equineassisted reproduction. Single layer centrifugation (SLC) of spermatozoa has been shown to improve the quality of stallion sperm samples. In this study, the functionality of selected stallion spermatozoa was tested by intracytoplasmic sperm injection of equine oocytes after selection by SLC through Androcoll-E or ...

The principal objective of this study was to derive an improved procedure for cryopreservation of swamp buffalo (Bubalus bubalis) spermatozoa. Experiments were conducted to determine effects of cooling rate, intermediate plunge temperature and warming rate on motility and acrosome integrity of spermatozoa. Spermatozoa were obtained from three bulls (three ejaculates/bull) and were subjected to ...