Ann. Entomol. Soc. Am. 81(2): 292-300 (1988) ABSTRACT We have examined the ultrastructure of post meiotic eupyrene sperm maturation in testes of prepupae, pupae, and adult Heliothis virescens (F.) males. Emphasis was placed on the structures present in the elongating sperm tail. In each young spermatid, each cell has a nucleus, acrosome derivative, and numerous mitochondria in a large volume of...

spermatogenesis and spermiogenesis, mam-malian spermatozoa leaving the testis appear to be morphologically mature but clearly are immature from a functional standpoint; that is, they have acquired neither progressive motility nor the ability to fertilize a metaphase II–arrested egg. Although progressive motil-ity is acquired and signaling pathways mature during sperm transit through the epididy...

For assisted reproduction technologies (ART), numerous techniques were developed to isolate spermatozoa capable of fertilizing oocytes. While early methodologies only focused on isolating viable, motile spermatozoa, with progress of ART, particularly intracytoplasmic sperm injection (ICSI), it became clear that these parameters are insufficient for the identification of the most suitable sperma...

Proteins known to function during cell-cell communication and exocytosis in neurons and other secretory cells have recently been reported in human sperm. Synapsins are a group of proteins that have been very well characterized in neurons, but little is known about synapsin function in other cell types. Based upon previous findings and the known function of synapsin, we tested the hypothesis tha...

Background Although the depth of the counting chamber is an important factor influencing sperm counting, no research has yet been reported on the measurement and comparison of the depth of the chamber. We measured the exact depths of six kinds of sperm counting chambers and evaluated their accuracy. MaterialsAndMethods In this prospective study, the depths of six kinds of sperm counting chamber...

semen collection evaluation and addition of preservatives to increase storage period of sperm are essential for successful artificial insemination. this study was conducted on 4rams (2 ghezel merinos and 2 merinos moghani) to evaluate the effect of two diluents in khalatposhan research station. average age of rams was 3 years. rams were trained to serve the artificial insemination and semen sam...

Background: The purpose of this study was to examine the impact of Insulin (INS) on human sperm function, in light of a recent proteomic analysis indicating that these cells express the INS receptor (INSR). Materials and Methods: We used Western blot and Immunocytochemical analyses. Results: Immunocytochemical analyses confirmed the presence of INSR in human spermatozoa and localized this recep...

Background: ROS production is a well-established phenomenon during sperm cryopreservation. Therefore, supplementation of freezing media with antioxidant is an inevitable event. The aim of this study was to assess whether a cell permeable superoxide dismutase agent such as MnTE, can further improve the quality of frozen/ thawed semen sample using a commercially optimized sperm cryopreservation m...