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While hyperactivated motility is known to be a concomitant of capacitation, and a prerequisite for fertilization, the specific interdependence of capacitation and hyperactivation in human spermatozoa has not been investigated. This study was designed to determine the effect of seminal plasma contamination on the expression of hyperactivated motility and the(More)
For technical reasons sperm head movement is assessed in kinematic analysis, while flagellar movement is the determining factor of head movement, not vice versa. It follows then that the development of new kinematic values to describe the movement of capacitating human spermatozoa should include the analysis of their flagellar movement. The aim of this(More)
Human spermatozoa were prepared by swim-up from semen into in-vitro fertilization (IVF) culture medium, and their movement recorded by videomicrography using NTSC video to give 60 images/s on freeze-frame playback. Trajectories in which spermatozoa appeared to switch from one type of motility pattern to another (from non-hyperactivated to transitional or(More)
While head centroid-derived kinematic values have been determined for the trajectories of hyperactivated human spermatozoa, the definitions are not robust with respect to image sampling frequency and track analysis methods. The determination of the fractal dimension of a trajectory has been suggested as an alternative descriptive parameter for(More)
In this research study, we investigate issues of trust that affect online consumers' decisions to purchase goods on an e-business website. What elements of the site interface make a difference in a person's decision to trust a firm (or not) when visiting the site for the first time with no prior knowledge of the firm? What elements of the website enhance or(More)
An alternative approach to the treatment of type I diabetes is the use of genetically altered neoplastic liver cells to synthesize, store and secrete insulin. To try and achieve this goal we modified a human liver cell line, HUH7, by transfecting it with human insulin cDNA under the control of the cytomegalovirus promoter. The HUH7-ins cells created were(More)
Reactivated movement of the axonemes in demembranated spermatozoa with decondensed nuclei allows decondensation to be monitored in vitro with minimal disruption, and provides access to the nucleus for ultrastructural investigation and experimental manipulation. In the present study, fresh liquefied semen samples with sperm concentrations > or = 13 x(More)
In order to design a feasible somatic cell gene delivery system for the treatment of type I diabetes, a suitable cell type needs to be determined. We have previously shown that the stable transfection of the full-length insulin cDNA into the human liver cell line, (HEP G2ins) resulted in synthesis, storage and acute regulated release of insulin to analogues(More)
(E)-4-hydroxy-2-nonenal (HNE) is a lipid peroxide end-product which exerts powerful biological effects in a variety of cell and tissue systems. The effects of exogenous HNE on ram spermatozoa were examined in vitro. HNE inhibited the motility of diluted ram spermatozoa in a dose-dependent (100-400 mumol l-1) manner (P < 0.05). The extent of motility loss(More)
As part of our research into the liver-directed gene therapy of Type I diabetes, we have engineered a human hepatoma cell line (HEPG2ins/g cells) to store and secrete insulin to a glucose stimulus. The aim of the present study was to determine whether HEPG2ins/g cells respond to glucose via signaling pathways that depend on ATP-sensitive potassium channels(More)