Sperm transport from the external cervical os to the fallopian tubes in women: a time and quantitation study.
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Adult↗
Biomedical subjects
D R Tredway
Publications and source records attributed to D R Tredway.
Colposcopy and cryosurgery in cervical intraepithelial neoplasia.
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Adolescent↗
Association of human sperm nuclear decondensation and in vitro penetration ability.
Sperm nuclear decondensation is an integral step in fertilization which leads to the formation of the male pronucleus. The association between the in vitro spontaneous nuclear decondensation of human sperm and its fertilizing ability was studied in infertile male patients. The ability of sperm to fertilize an egg using the discontinuous two-layer Percoll method was significantly correlated to the percentage of decondensed swollen head (r = 0.43; P less than 0.005). The fertilizing ability of sperm processed with Test-Yolk buffer was correlated with the percentage of sperm at the fully decondensed stalk stage (r = 0.51; P less than 0.05). There were insignificant correlations for the whole-wash centrifugation, cryopreserved-thawed and swim-up methods. Samples of sperm that were positive (greater than 0% fertilization) in the sperm penetration assay had a higher percentage of decondensed sperm heads (66.7% vs. 20.6%) after Percoll wash or whole-wash centrifugation (60.5% vs. 44.3%) treatments compared with samples with no fertilization. Treatments that included Test-Yolk resulted in high percentages of decondensed swollen heads. The results suggest a positive association between sperm nuclear decondensation and the fertilizing ability of sperm, and affirm the importance of nuclear decondensation to the study of fertilization events.
Animals↗
Diadenosine tetraphosphate (Ap4A) and triphosphate (Ap3A) signaling of human sperm motility.
The ubiquitous dinucleotide polyphosphate, diadenosine tetraphosphate (Ap4A), has been shown to be a signal molecule for DNA replication in mammalian cells. In this study, Ap4A and a related compound, diadenosine triphosphate (Ap3A), were tested for possible signaling functions in human spermatozoa. A computerized automated semen analyzer was used to detect changes in spermatozoa motility parameters. Cryopreserved-thawed donor spermatozoa were washed and incubated in 0.1 mM Ap4A, 0.1 mM Ap3A, or control medium. The data indicated that both Ap4A and Ap3A decreased the percentage of motile spermatozoa after 4 or more hours of incubation in vitro. The two dinucleotide polyphosphates caused an increase in the amplitude of lateral spermatozoa head displacement parameter only at the start of incubation. The other spermatozoa kinematic parameters were unaffected. No opposing ying-yang dual actions of Ap4A to Ap3A were seen. From the results, Ap4A and Ap3A were observed to be potential inhibitory signals of spermatozoa motility after prolonged exposure.
Dinucleoside Phosphates↗
A double method sperm wash for artificial insemination.
Recently, there have been concerns regarding the presence of reactive oxygen species (ROS) produced during sperm processing for insemination. However, the sperm wash methods that yielded low ROS levels also had low sperm recovery after processing. The objective of this study was to compare sperm recovery after swim-up from pellet, overlay, and 2-layer Percoll wash methods with the recovery after the double method wash. The latter method consisted of a combination of 2 sperm wash methods, namely, the overlay and the Percoll method. Motile sperm were first collected through the overlay method. The leftover semen was then processed through the 2-layer Percoll method to scavenge motile sperm and the resultant pellet combined with the pellet from the overlay method. In this manner, the level of ROS was kept to a minimal, sperm recovery was improved, and a mixture of sperm with different surface properties was produced as a result of using different processing methods. The results indicated an improvement in sperm recovery and in total sperm motility in noncryopreserved sperm after using the double method wash when compared with the other wash methods. The study suggests that the double method wash is a feasible method for processing sperm for insemination.
Cell Separation↗
Clinical pregnancy rate after the double method wash and intrauterine insemination.
The protocol for intrauterine insemination (IUI) involves sperm processing using different methods that have produced varying results. These sperm wash methods do not take into consideration the problems of the exact timing of ovulation and the requirements of sperm cells at different stages of capacitation. The objectives of this study were 1) to use the double method wash previously reported to produce a mixture of different populations of sperm cells and determine the pregnancy outcome after IUI and 2) to compare the sperm kinematic parameters after the double method wash with those after the centrifuge (or whole-population) wash method. Patients were divided into either the double method group (n = 119) or the centrifuge method group (n = 76). The Hamilton-Thorn HTM-C automated sperm motility analyzer (Hamilton-Thorn Research, Danvers, MA) was used to analyze sperm motility parameters. Pregnancy outcomes were evaluated after controlled ovarian stimulation and IUI. An almost 2-fold increase was seen in the pregnancy rate with the double method wash compared with the centrifuge method wash. Sperm motility and velocity were also enhanced in the double method wash groups. The results support the usefulness of the double method wash for the preparation of sperm for IUI.
Female↗
Follicular phase hormonal profiles during administration of leuprolide for in vitro fertilization.
Hormonal changes induced during short-term administration of leuprolide were evaluated during the follicular phase in 57 patients who completed an IVF cycle. They were compared with those of 14 patients who were placed on long-term suppression. There was an unexpected abnormal increase in serum progesterone during the first week of the cycle in nine of the 57, with no significant change in the fertilization and cleavage rate; however, no pregnancy was achieved in this group. Transient mild elevation of progesterone was also detected in 16 patients with no adverse effect on fertilization and the outcome of the IVF. In the long protocol, the tonic levels of LH, FSH, and progesterone remained low throughout the follicular phase. The total number of pregnancies was higher in the short suppression regimen, but the full-term pregnancy rates were similar in both protocols.
Adult↗
Predictive value of sperm hyperactivation measurements based on the dilution effect method in clinical in vitro fertilization.
Sperm hyperactivation motility characterized by wide oscillatory movements of the sperm head, nonlinear directions, and rapid motility with occasional star-shaped pattern of movement was measured during routine semen analyses prior to an in vitro fertilization procedure. The method consisted of diluting liquefied semen 1:20 with Ham's F-10 supplemented with processed human cord sera followed by incubation at 37 degrees C for 30 minutes. At the end of the incubation period, aliquots of semen samples were evaluated by phase contrast microscopy for sperm hyperactivation. The results indicated that (1) sperm samples exhibiting 15% or more hyperactive motility were associated with a significantly higher percent fertilization of oocytes during the IVF procedure; (2) sperm hyperactive motility was correlated to sperm fertilizability during IVF treatment cycles.
Female↗