Aneuploidy commonly causes spontaneous abortions, stillbirths, and aneuploid births in humans. Notably, the majority of sex chromosome aneuploidies in live births have a paternal origin. An increased frequency of aneuploidy is also associated with male infertility. However, the dynamics and behavior of aneuploid spermatozoa during fertilization in humans have not been studied in detail. Therefo...

The oviduct occupies a unique position in mammalian reproduction as the site of sperm transport, the final maturation of sperm and egg, fertilization, and the initial development of the embryo. This dissertation examines the factors that control the number, distribution and physiological state of spermatozoa in the oviduct. The golden hamster (Mesocricetus auratus) was used as the animal model....

Many of the world's wild feline species are threatened by extinction. Gene banks are created with the aim of preserving their genetic materials. In case of unexpected death of the animals, epididymal sperm preservation can be used to avoid loss of genetic material. However, one requirement for the genetic preservation of endangered species is to preserve as much genetic material as possible. Th...

Chemotaxis of spermatozoa to female gonophores has been shown to occur in Campanularia, Tubularia and other hydroids (Miller, 1966 a, b). Cinemicrographic records of the movements of Campanularia spermatozoa in the vicinity of female gonophores or of glass capillary pipettes containing extracts of female hydranths have shown that chemotactic aggregation of the spermatozoa occurs because the spe...

In order to find an optimal hypo-osmotic swelling test (HOST) and to identify viable sperm cells from patients with asthenozoospermia for intracytoplasmic sperm injection (ICSI), we tested single motile and non-motile spermatozoa in four hypo-osmotic solutions by micromanipulation. The four solutions were: A, H2O; B, 50 mOsm NaCl; C, 150 mOsm NaCl and D, 150 mOsm sodium citrate and fructose. Eo...

Flagellar movement of golden hamster spermatozoa obtained from the testis and the caput and cauda epididymides was observed by a light microscope while holding them at their heads with a micropipette. Flagellar movement of capacitated spermatozoa and of reactivated spermatozoa demembranated with Triton X-100 was also observed. Testicular and caput epididymal spermatozoa showed weak movement in ...

Recombination of different strains and subtypes is a hallmark of lentivirus infections, particularly for human immunodeficiency virus, and contributes significantly to viral diversity and evolution both within individual hosts and within populations. Recombinant viruses are generated in individuals coinfected or superinfected with more than one lentiviral strain or subtype. This, however, has n...

Xanthine oxidoreductase (XOR) is a molybdoflavoprotein mainly involved in purine catabolism. It exists in two forms, the oxidase (XO) and dehydrogenase (XDH) which are inter-convertible within mammalian cells. Although various researchers have reported the extraction of mammalian XOR, no extractions have yet been carried out in Malta and subsequently no characterizations are available. In this ...

BACKGROUND Externalization of phosphatidylserine (EPS) occurs in apoptotic-like spermatozoa and could be used to remove them from sperm preparations to enhance sperm quality for assisted medical procreation. We first characterized EPS in sperms from infertile patients in terms of frequency of EPS spermatozoa as well as localization of phosphatidylserine (PS) on spermatozoa. Subsequently, we det...