Intact sperm cells of Plumbago zeylanica were released from mature pollen grains near anthesis using osmotic shock with 20% sucrose. Sperm cell yields of up to 75% can be attained by differential centrifugation using a clinical centrifuge with concentrations of up to 8.8 x 10(6) cells/milliliter. Such ;gametoplasts' remain intact for up to 24 hours according to Evan's blue exclusion and can be ...

The purpose of this study was to characterize highly enriched human spermatozoa membrane proteins by two-dimensional electrophoresis and computer image analysis. Sperm membrane proteins were extracted by detergent solubilization from three different preparations: 1) washed semen cells following centrifugation and three wash steps in Ham's F-10 medium (the standard sperm preparation, which is co...

The isolation and characterization of three Caenorhabditis elegans temperature-sensitive mutants that are defective at fertilization are described. All three are alleles of the gene fer-1. At the restrictive temperature of 25 degrees, mutant hermaphrodites make sperm and oocytes in normal numbers. No oocytes are fertilized, although they pass through the spermatheca and uterus normally. The ooc...

Introduction Automated methods for sperm characterization in microscopic videos have some limitations such as: low contrast of the video frames and possibility of neighboring sperms to touch each other. In this paper a new method is introduced for detection of sperms in microscopic videos. Materials and Methods In this work, first microscopic videos are captured from specimens of human semen. S...

introduction automated methods for sperm characterization in microscopic videos have some limitations such as: low contrast of the video frames and possibility of neighboring sperms to touch each other. in this paper a new method is introduced for detection of sperms in microscopic videos. materials and methods in this work, first microscopic videos are captured from specimens of human semen. s...

Mechanisms of mammalian sperm migration through the female reproductive tract and ovum vestments are described. The perspective is biophysical as well as biochemical and morphological, and the focus is upon the role of sperm motility in these processes. Sperm forward progression is characterized as an interactive process between the the cell and its environment, and the mediation of flagellar b...

Cellular membranes are heterogeneous, and this has a great impact on cellular function. Despite the central role of membrane functions in multiple cellular processes in sperm, their molecular mechanisms are poorly understood. Membrane rafts are specific membrane domains enriched in cholesterol, ganglioside GM1, and functional proteins, and they are involved in the regulation of a variety of cel...

In the female reproductive tract, mammalian sperm undergo a regulated sequence of prefusion changes that "prime" sperm for fertilization. Among the least understood of these complex processes are the molecular mechanisms that underlie sperm guidance by environmental chemical cues. A "hard-wired" Ca(2+) signaling strategy that orchestrates specific motility patterns according to given functional...

Progesterone, primarily recognized as a female steroid hormone, is reported to affect several sperm functions especially capacitation, motility and acrosome reaction. These effects of progesterone on the spermatozoa are mediated via the progesterone binding sites/progesterone receptor (PR) on the acrosomal membrane. These receptors in response to progesterone increase the intercellular Ca2+ lev...