A Trypanosoma brucei TbGPI12 null mutant that is unable to express cell surface procyclins and free glycosylphosphatidylinositols (GPI) revealed that these are not the only surface coat molecules of the procyclic life cycle stage. Here, we show that non-GPI-anchored procyclins are N-glycosylated, accumulate in the lysosome, and appear as proteolytic fragments in the medium. We also show, using ...

BACKGROUND Cryopreservation has been extensively used in assisted reproductive technology, agriculture and conservation programmes for endangered species. The literature reports largely positive results regarding the survival of frozen-thawed cells and clinical outcomes. Nonetheless, it is unclear whether or not cryopreservation of sperm, oocytes and embryos causes any disruption in their genet...

Background: Sperm cryopreservation has been associated with over production of reactive oxygen species (ROS). Buffalo spermatozoa are susceptible to ROS inducing damages due to insufficient level of cytoplsmic antioxidant along with high amount of poly unsaturated fatty acids composition in membrane structure. Therefore, appropriate antioxidant in buffalo cryopreservation extender would reduce ...

Egg yolk (EY) and glycerol are common constituents of extenders used for sperm cryopreservation. It has been demonstrated that using cholesterol-loaded cyclodextrins (CLC) improves sperm cryosurvival in several species. However, standard freezing extenders might not be the most appropriate for CLC-treated sperm. This study evaluated the EY and glycerol requirements for freezing CLC-treated boar...

Modern biotechnologies are used extensively in the animal breeding industry today. Therefore, it is essential that sperm handling procedures do not modulate the normal physiological mechanisms occurring in the female reproductive tract. In this paper, the different selection mechanisms occurring in vivo are described briefly, together with their relevance to artificial insemination, followed by...

Background: Sperm cryopreservation-thawing process has damaging effects on the structure and function of sperm, namely cryoinjury. Calcium overload has been reported as a postulated mechanism for sperm damage during the first steps after thawing. This study was designed to assess the intracellular calcium (Ca2+i) after cryopreservation and to clarify the role of a calcium chelator ethylene glyc...

The introduction of the technique of intracytoplasmic sperm injection to achieve fertilization, especially using surgically retrieved testicular or epididymal sperm from men with obstructive or non-obstructive azoospermia, has revolutionized the field of assisted reproduction. The techniques for the retrieval of spermatozoa vary from relatively simple percutaneous sperm aspiration to open excis...

in the present study, the fertilizing potential of semen recovered from slaughtered bulls epididymis was evaluated after cryopreservation, by conventional techniques and flow cytometry methods. the cauda epididymal was dissected and sperm were recovered and evaluated for volume, sperm concentration, and membrane and acrosome integrity using a flow cytometer. sperm fertility potential was tested...

Sperm motility stimulation is a pharmacological treatment used to improve sperm motility and treatment outcome in frozen-thawed epididymal and testicular spermatozoa. Sperm motility is a critical factor in male fertility. Low motility can be caused by a variety factors including abnormal spermatogenesis, oxidative damage, or depletion of intracellular adenosine triphosphate (ATP; molecule that ...

Background Cryopreservation of semen requires optimized conditions to minimize the harmful effects of various stresses. The main approach for protection of sperm against stress is based on the use of antioxidants and cryoprotectants, which are described as defensive methods. Recently, the application of controlled mild stressors has been described for activation of a temporary response in oocyt...