OBJECTIVE To study the resistance of human spermatozoa to cryoinjury in repeated cycles of thaw-refreezing by using the fast liquid nitrogen vapor method. MATERIALS AND METHODS Semen specimens were obtained from sixteen normal and oligozoospermic individuals who required disposal at the sperm bank. Five of them had testicular cancer. Specimens were thawed and an aliquot was removed for analys...

AIM To study whether additional measurements of motility characteristics of spermatozoa by computer assisted semen analysis (CASA) were more sensitive indicators of reduced semen quality than estimates of percentages of motile, rapid or progressive cells. METHODS Intermittent scrotal insulation was applied to 6 rams for 16 h per day for 21 days or to 2 of these for 12 h per day for 28 days in...

Lepidopteran males produce eupyrene (nucleate) and apyrene (anucleate) spermatozoa, but in the female only eupyrene spermatozoa leave the spermatheca and fertilize the eggs. Both kinds of spermatozoa lack intrinsic motility in the male genital duct. They become motile in the spermatophore, in a process involving proteases from the male duct. In vitro, trypsin induces immotile spermatozoa to bec...

OBJECTIVES Evaluation of the presence of spermatozoa in vas deferens fluid after a long interval of unilateral and homolateral percutaneous epididymal sperm aspiration (PESA) in vasectomized men. When found, the spermatozoa were evaluated including concentration and motility, in order to verify the patency of the epididymal tubules. MATERIALS AND METHODS Four patients, numbered in a progressi...

Epididymal spermatozoa of domestic cats were diluted with TEST medium and frozen. The parameters - estimated percentage of motile spermatozoa, concentration of spermatozoa, cell morphology and transmigration rate (TMR) - were evaluated before freezing and after thawing. Transmigration is a new method to measure the percentage of spermatozoa that consistently move forward, and has not been inves...

The aim of this study was to identify different motile sperm subpopulations in ejaculates from an autochthonous bull breed (Bos taurus) and to determine possible modifications in these subpopulations resulting from cryopreservation. Ejaculates were collected and cryopreserved following a conventional protocol. The overall sperm motility and the kinematic parameters of individual spermatozoa wer...

In this study, total glutathione content was determined in human spermatozoa before and after cryopreservation. Total GSH in fresh semen was 4.47±0.46nmol/10(8) cells. Following semen cryopreservation, GSH decreased to 1.62±0.13nmol/10(8) cells, a 64% reduction (p<0.01). This decrease in GSH content was associated with a decrease in sperm progressive motility (68% of reduction, p<0.01). Additio...

OBJECTIVE To evaluate and compare standard sperm parameters, lipid peroxidation of sperm plasma membranes, antioxidant capacity of seminal plasma, and sperm chromatin integrity in ejaculates from men whose partners have a history of recurrent pregnancy loss and from a control group of men with recent fertility. DESIGN Descriptive study. SETTING Reproduction Program, University of Antioquia,...

CONTEXT Several sperm retrieval techniques are available for use on azoospeermic men. Comparisons between spermatozoa retrieved from the testicles and epididymis in relation to pregnancy and miscarriage rates are not well established. OBJECTIVE To compare pregnancy and miscarriage rates using sperm retrieved from the testes and epididymis using intracytoplasmic sperm injection. Furthermore, w...

Peroxidation of the sperm cells’ own phospholipids, closely bound up with declining motility, has been demonstrated in human spermatozoa; the rate of peroxidation was determined quantitatively by the reaction with thiobarbituric acid. Immotile or poorly motile spermatozoa from necrospermic or oligospermic semen exhibited a higher rate of peroxidation than highly motile spermatozoa from normal e...