Biomedical subjects

A A Pacey

Publications and source records attributed to A A Pacey.

22 records · Page 2Linked to original sources

PubMed1994

The sequential effects of human cervical mucus, oviductal fluid, and follicular fluid on sperm function.

OBJECTIVE: To compare the sequential effects of human cervical mucus (CM), oviductal fluid, and follicular fluid (FF) on sperm motility, hyperactivation, and the acrosome reaction during 9 hours of incubation in vitro. DESIGN: Spermatozoa from a fertile donor were allowed to penetrate human CM in vitro and then were recovered and incubated in either 30% human oviductal fluid or a simple salt solution for 3 hours before challenge with 20% FF. Thus, the sequential effects of the fluids collected from the female reproductive tract on sperm hyperactivation and acrosome reaction were examined. SETTING: The donor insemination program at the University Clinic within the Jessop Hospital for Women, Sheffield, United Kingdom. PATIENTS: All donors used in this study were involved in the donor insemination program. MAIN OUTCOME MEASURES: Sperm motility, hyperactivation, and percentage of acrosome-reacted spermatozoa were measured. RESULTS: This study used an in vitro technique to mimic sperm transport in vivo. Spermatozoa sequentially incubated with female reproductive tract secretions in vitro showed a maintenance in the level of FF-induced hyperactivated motility and a decreased response to the FF-induced acrosome reaction when compared with sperm challenged with FF in the absence of prior incubation with human oviductal fluid. CONCLUSION: It is suggested that human oviductal fluid may serve to delay the FF-induced acrosome reaction.

Acrosome↗

PubMed1994

Computer-assisted measurement of hyperactivation in human spermatozoa: differences between European and American versions of the Hamilton-Thorn motility analyser.

Spermatozoa from healthy donors of proven fertility were analysed for percentage hyperactivation, mean curvilinear velocity (VCL), mean progressive velocity (VSL), amplitude of lateral head displacement (ALH) and percentage linearity (LIN) using two versions of the Hamilton-Thorn motility analyser (HTMA) running at different frame rates. The sort fraction criteria developed using a machine utilizing 30 Hz gave comparable figures for the percentage spermatozoa displaying motility patterns concomitant with hyperactivation when compared to that developed for a machine using a frame rate of 25 Hz. Statistically significant differences were observed when criteria developed using 30 Hz machines were transferred to those using 25 Hz. The frame rate dependency of VSL and VCL are thought to account for these differences; values for ALH and LIN were largely unaffected by frame rate. These results have implications for workers using the European version of the HTMA (at 25 Hz) with sort criteria, containing frame rate-dependent variables, which have been developed by American colleagues using the machines of a higher frame rate. More appropriate sort criteria for workers using European (25 Hz) machines are suggested.

Computers↗

PubMed1994

Human oviductal fluid prolongs sperm survival.

OBJECTIVE: To compare the effect of human oviductal fluid on sperm motility and hyperactivation during 9 hours' incubation in vitro with follicular fluid (FF) and medium controls. DESIGN: Fertile donor spermatozoa were allowed to penetrate human cervical mucus in vitro and then recovered and incubated in either 30% human oviductal fluid, 20% FF, or medium for up to 9 hours. Sperm motion characteristics were measured using a sperm motility analyzer. SETTING: The donor insemination program at the University Clinic within the Jessop Hospital for Women, Sheffield, United Kingdom. PATIENTS: All donors used in this study were involved in the donor insemination program. MAIN OUTCOME MEASURES: Sperm motility, hyperactivation, curvilinear velocity, progressive, lateral head displacement, and linearity were measured using a sperm motility analyzer. RESULTS: After 9 hours' incubation, spermatozoa in human oviductal fluid had a significantly higher percentage motility than sperm incubated in FF or the control medium. A more linear sperm motion was consistently observed in the spermatozoa incubated in human oviductal fluid: significantly different from FF and media at 3 hours and 6 hours. The effect of human oviductal fluid on maintaining sperm motility was not affected by the addition of P. CONCLUSION: Human oviductal fluid can maintain sperm motility in a mechanism that is not mediated by the low concentration of P. We suggest that human oviductal fluid is a favorable environment for sperm survival.

Body Fluids↗

PubMedDate not supplied

The potential shortcomings of measuring hyperactivated motility by computer-aided sperm analysis when sperm motion is multiphasic.

This paper was written from the standpoint that computer-aided sperm analysis (CASA) instruments, which capture a 'snapshot' of sperm trajectories in order to generate their data, may provide a poor measure of hyperactivated motility in a sperm population where hyperactivation is multiphasic in nature. To illustrate this point, a series of theoretical sperm populations were constructed which varied subtly but significantly in the nature of the hyperactivated behaviour expressed by spermatozoa. The parameters which were manipulated were: (i) the number of hyperactivated phases exhibited within a given period of time; (ii) the duration of these phases; and (iii) proportion of spermatozoa within the population which exhibited hyperactivated phases. These populations were then subject to an analysis in which snapshots of sperm motion were examined to determine the percentage of hyperactivated spermatozoa for that population. The results indicated that whilst this snapshot approach to quantifying hyperactivation could provide a figure for the percentage of hyperactivated spermatozoa within the sample window, this often inaccurately described the underlying behaviour of the population. Since there is very likely to be a significant amount of biological information contained within the nature of multiphasic behaviour, this paper has argued that this aspect of snapshot analysis is one which requires serious consideration by CASA manufacturers and medical researchers.

Diagnosis, Computer-Assisted↗