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M Perez-Pelaez

Publications and source records attributed to M Perez-Pelaez.

At least 19 recordsLinked to original sources
PubMed1989

Preincubation of human spermatozoa in test-yolk medium: effect on penetration of zona-free hamster oocytes and correlation with other semen characteristics.

Penetration of zona-free hamster oocytes by human spermatozoa after preincubation with BWW medium (standard technique) or a buffer system containing egg yolk (TESTY) was compared by applying both treatments to aliquots of 60 ejaculates from 34 patients. The TESTY-treated spermatozoa penetrated the oocytes much more successfully than the spermatozoa treated by the standard technique. Although the penetration levels achieved by the two methods were significantly correlated, the correlation coefficient was too low to predict the penetration outcome from one technique to the other. More consistent results were obtained when different ejaculates from the same donor were treated by TESTY than by the standard technique. Spermatozoan penetrating ability was more strongly correlated with sperm concentration, motility, and morphology after treatment by the standard technique than after TESTY treatment. Much larger differences in penetration were present between normal and abnormal ejaculates when the standard technique was used than TESTY.

Animals↗
PubMed1989

Morphometric and volumetric comparisons of human spermatozoa.

Morphometric measures and volumes of spermatozoa were determined for 28 human ejaculates which were previously analyzed for semen volume, sperm concentration, morphology, motility, and fertility by in vitro fertilization procedures (IVF). Morphometric measurements of sperm heads were analyzed using a Zeiss Videoplan computer, while spermatozoan volume was determined with an Elzone particle analyzer. Though a strong relationship was anticipated, correlations between the volumetric data and different morphometric measures revealed poor, insignificant values. This lack of correspondence may be due to individual differences in the thickness of the spermatozoa within a sample. Twenty-two of the ejaculates used in this study were classified as fertile and six were infertile according to the IVF procedure results. Correlations between the morphometric measurements and the volume determinations in the fertile group were all positive. In contrast, those of the infertile group were all negative with one exception (width vs. volume).

Fertility↗
PubMed1988

Glass wool column filtration of human semen: relation to swim-up procedure and outcome of IVF.

The number and viability of spermatozoa recovered by glass wool column filtration and a swim-up procedure were compared using different types of ejaculates, such as normal, asthenozoospermic and very viscous oligozoospermic semen. The filtration procedure resulted in significantly (P less than 0.01) higher recovery of viable spermatozoa than the swim-up procedure from all types of ejaculates studied. Further, the spermatozoa from 50 (78.1%) of the 64 ejaculates filtered through glass wool column fertilized at least one intact human egg in an in-vitro fertilization (IVF) procedure. It is concluded that glass wool column filtration is superior to the swim-up procedure since it yields a higher recovery of viable spermatozoa that are potentially fertile. Therefore, the glass wool column filtration procedure used to prepare spermatozoa may be of benefit for IVF, intra-uterine insemination, in-vitro fertilization and GIFT (gamete intra-Fallopian transfer), especially in cases of poor quality semen.

Cell Separation↗
PubMed1987

Leucospermia and the fertilizing capacity of spermatozoa.

Ejaculates obtained from men attending an in vitro fertilization (IVF) program were analyzed to determine the effect of the presence of leucocytes in semen on the ability of sperm in that semen to fertilize oocytes. The mean (+/- S.E.) concentration of leucocytes in 103 ejaculates was 0.62 X 10(6)/ml (+/- 0.09) with a range of 0.1 X 10(6) or less per ml to 7.0 X 10(6)/ml. The leucocyte concentration demonstrated a significant (p less than 0.05) but inverse relationship with the fertilizing capacity of spermatozoa. Though not statistically significant, the leucocyte concentration also demonstrated an inverse relationship to sperm motility and normal morphology. These results suggest that the presence of leucocytes in an ejaculate cannot be used as the sole indicator of the fertilizing capacity of spermatozoa in that ejaculate.

Female↗
PubMed1987

Effect of fluoxymesterone therapy on semen quality in the treatment of subfertile men.

The use of androgen therapy to improve the poor quality of semen was assessed on 69 subfertile men. The men were treated with 2 or 4 mg of fluoxymesterone daily up to 12 months. During the course of treatment, the semen samples were analyzed every 3 months and the overall mean values for various semen characteristics were compared before and after the onset of treatment. The sperm motility and normal sperm morphology showed a significant improvement with treatment. Based on overall evaluation, androgen therapy may benefit some patients, while in others it may not significantly alter the semen quality.

Fluoxymesterone↗
PubMed1986

Association of the in-vitro fertilizing capacity of human spermatozoa with sperm morphology as assessed by three classification systems.

Stained sperm morphology slides from an in-vitro fertilization programme were evaluated by the modified Williams system, the World Health Organization (WHO) system and morphometric size measurements (image analysis) to determine which system(s) were better predictors of fertility. Amorphous sperm head shape was the best predictor of fertility in both the modified Williams system and the WHO system, predicting the proper fertility status in 65% of the cases. Using only normal sperm in the statistical model, normal sperm became a correct predictor in 66% of the cases in the modified Williams system. Morphometric measurements were not useful in predicting the fertility status of these samples. These studies indicate that morphology can not be used as a sole predictor of fertilizing capacity of human spermatozoa.

Fertility↗
PubMed1986

Evaluation of acrosome on Papanicolaou-stained sperm and its relationship to the in vitro fertilizing capacity of human spermatozoa.

Papanicolaou-stained sperm smears from 1150 ejaculates evaluated from infertility clinic patients and 166 ejaculates in an in vitro fertilization program were studied for the presence of acrosomal abnormalities. Morphologically, a normal acrosome was defined as a sperm having a ratio of 1:1 to 2:1 between the acrosome and postacrosomal part in an oval or round, uniformly shaped head. Acrosomal abnormality was identified in at least a few of the spermatozoa in all the ejaculates (range 8-98%) and appeared to be closely related to normal sperm morphology (r = 0.85). A significantly higher (p less than 0.01) correlation (r = 0.31) was noted between the presence of normal acrosome and in vitro fertilizing capacity of spermatozoa as compared to other standard semen characteristics. Acrosome can be identified on Papanicolaou-stained smears, and since it appears to be related to fertility it may be beneficial to evaluate the acrosome morphologically during routine semen analysis.

Acrosome↗
PubMed1986

Concentration of viable spermatozoa for artificial insemination.

Glass wool microfiber code 112 (approximately 30 mg) was gently packed to a depth of 3 mm in a 3-ml disposable syringe barrel. The column was rinsed repeatedly with Tyrode solution to remove loose glass wool fibers. Approximately 0.3 to 0.5 ml of concentrated spermatozoa (after centrifugation of semen at 500 X g for 5 minutes) was layered over the wet column and allowed to filter by gravity. The filtered spermatozoa demonstrated a significantly higher (P less than 0.001) mean percentage of motility, progressive motility, sperm unstained by eosin Y dye, and sperm with functionally intact membranes. Although there was a considerable loss of sperm, the filtered specimen contained all viable spermatozoa present before filtration. Therefore, it appears that this procedure yields a high percentage of viable spermatozoa, potentially capable of fertilization, for use in in vitro fertilization or, possibly, artificial insemination.

Cell Separation↗
PubMed1985

Nonbeneficial effects of glycerol on the oocyte penetrating capacity of cryopreserved and incubated human spermatozoa.

The effect of cryopreservation on human spermatozoa in the presence or absence of glycerol was assessed by using sperm motility, functional integrity of sperm membrane, and denuded hamster oocyte penetration tests. Glycerol treated cryopreserved spermatozoa yielded a significantly higher (P less than 0.01) percentage of motile sperm and percentage of sperm with functionally intact membrane immediately after thawing than the spermatozoa not treated with glycerol but cryopreserved. However, no significant difference was observed between these cryopreserved spermatozoa (either treated or untreated with glycerol) on the percentage of motile sperm and the rate of oocyte penetration when the sperm were washed and incubated for 2 hr in a medium containing no glycerol. Thus, it appears glycerol may not be beneficial, since cryopreservation of spermatozoa either treated or untreated with glycerol essentially yields similar oocyte-penetrating capacity of sperm.

Female↗
PubMed1985

Ultrastructural categorization of human sperm cryopreserved in glycerol and in TESTCY.

The motility of human sperm after thawing and the ultrastructural integrity of their acrosomal region was evaluated in 5 semen donors after utilizing 2 cyproprotective extenders--glycerol and TESTCY. Sperm motility in the fresh control semen fraction (65.5% +/- 6.1) was significantly (P less than 0.05) better than the immediate post-thaw motility in both cyprotected fractions (38.8% +/- 2.0 for glycerol and 31.0% +/- 2.9 for TESTCY), and there was no significant difference between the two cyprotective treatments. The overall % of normal intact sperm heads was significantly less than in controls (P less than 0.05) following cypropreservation in glycerol, but values for sperm stored in TESTCY were not significantly different from controls or glycerol. However, when expressed as % change from controls values, sperm preservation was significantly better (P less than 0.05) in TESTCY than in glycerol. TESTCY is considered a better cryoprotective agent for human sperm.

Buffers↗
PubMed1985

Biochemistry of seminal plasma in azoospermic men.

Seminal plasma from 20 azoospermic and 4 vasectomized men and 75 samples from normal ejaculates were quantitated colorimetrically for zinc, fructose, and glycerylphosphorylcholine (GPC) contents. The results were similar to those obtained in the normal ejaculates, in 17 of 21 azoospermic ejaculates, whereas in the vasectomized ejaculates, GPC values were reduced. In the remaining 4 azoospermic ejaculates, less than 15% of fructose and GPC and a zinc content three times higher than normal were detected. Vasogram performed in these 4 azoospermic men revealed occlusion or aplasia of the ampula. The data suggest that biochemical evaluation may aid in differential diagnosis of the etiology of azoospermia.

Colorimetry↗
PubMed1985

Association of asthenozoospermia with a deficiency of a seminal glycoprotein.

Two major glycoprotein bands (Rf 0.67 and 0.49) were detected with polyacrylamide disc gel electrophoresis in normal human semen, spermatocele fluid and prostatovesicular fluid. The most rapidly migrating band (Rf 0.67) was either present in only trace amounts or absent in asthenozoospermic semen. The protein moiety of this glycoprotein was present in normal and asthenozoospermic semen, but it was not glycosylated in asthenozoospermic semen. It is suggested that there is a relationship between this glycoprotein and the acquisition of sperm motility.

Electrophoresis, Polyacrylamide Gel↗
PubMed1984

Development of an assay to assess the functional integrity of the human sperm membrane and its relationship to other semen characteristics.

The objective of this study was to develop a relatively simple test to evaluate the functional integrity of the membranes of human spermatozoa. As in some other species, human spermatozoa 'swell' under hypo-osmotic conditions due to the influx of water and the expansion of the membranes. A mixture of equal parts of fructose and sodium citrate (150 mosmol) with calculated ionic strength of 0.15 resulted in a maximal number of clearly identifiable swollen spermatozoa. Only small variations were seen when different aliquants of the same semen samples were separately evaluated. A high correlation (r = 0.94) was obtained between expected and observed values of swollen spermatozoa when known amounts of heat-treated spermatozoa, unable to undergo swelling, were added to untreated spermatozoa. A good correlation (r = 0.90) was also observed between the % spermatozoa in a semen sample that were capable of undergoing swelling and the % of denuded hamster oocytes that were penetrated by capacitated spermatozoa from the same semen sample. By contrast, the correlations between % sperm swelling in ejaculates and % normal sperm forms, % motile spermatozoa and % spermatozoa that do not stain with eosin-Y (supravital stain) in the same ejaculates were 0.30, 0.61 and 0.52, respectively. Therefore, the hypoosmotic swelling technique to evaluate the functional integrity of the sperm membrane appears to give high repeatability and accuracy and is closely correlated to the in-vitro fertilizing ability of spermatozoa. It may be a useful addition to the standard semen analysis.

Cell Membrane↗
PubMedDate not supplied

Comparison of glycerol and a zwitter ion buffer system as cryoprotective media for human spermatozoa. Effect on motility, penetration of zona-free hamster oocytes, and acrosin/proacrosin.

This study compared the cryoprotective effect of glycerol with that of a zwitter ion buffer system (TESTCY). Spermatozoa that are cryopreserved in the presence of glycerol possess a somewhat higher progressive motility immediately after thawing than those preserved in the presence of TESTCY. However, after a 1-hour incubation in glycerol-free medium, the progressive motilities of the glycerol- and TESTCY-treated spermatozoa become essentially identical. After 2 hours in culture medium, TESTCY-treated spermatozoa possess a higher motility than glycerol-treated spermatozoa, indicating that TESTCY is a better preservative than glycerol for the long-term motility of human spermatozoa. The fertilizing potential of the cryopreserved spermatozoa was assessed by their ability to penetrate zona-free hamster oocytes in vitro. Spermatozoa that are cryopreserved in the presence of TESTCY produce three- to four-fold higher penetration rates than glycerol-treated, cryopreserved spermatozoa. Cryopreservation in the presence of TESTCY also results in a higher stability of the acrosin/proacrosin system than when the spermatozoa are preserved in glycerol, since about two- to three-fold higher levels of proacrosin are retained. These results indicate that TESTCY is a better cryopreservative for human spermatozoa than glycerol.

Acrosin↗
PubMedDate not supplied

Correlation between human sperm swelling in hypoosmotic medium (hypoosmotic swelling test) and in vitro fertilization.

Human ejaculates (n = 83) were analyzed for standard sperm parameters (concentration, motility, and morphology), as well as for the ability of the spermatozoa to react (swell) in a hypoosmotic medium (Jeyendran et al, 1984). Subsequently, the fertilizing capacity of the spermatozoa was tested by their ability to fertilize human oocytes in vitro. Although the sperm concentration was adjusted for in vitro fertilization, no adjustments were made for sperm motility and morphology. Correlation of the in vitro fertilizing capacity of the spermatozoa with the hypoosmotic swelling test (r = 0.56) was much higher than with standard sperm parameters (r varied from -0.04 to 0.25). Complete overlap was noted with standard semen parameters whether the ejaculate did or did not fertilize oocytes and ranged from very low to very high values in both cases. By contrast, all the semen samples that fertilized oocytes showed a 60% or higher reaction in the hypoosmotic swelling test, whereas the majority of the "infertile" semen samples showed less than 60% swelling. It therefore appears that, under the conditions of our studies, the hypoosmotic swelling test is a more accurate predictor of successful in vitro fertilization outcome than the conventional semen parameters. A combination of all parameters, however, is likely to be most useful. The hypoosmotic swelling test is simple and economical, and it is recommended that this test be further scrutinized for its value as an additional tool in the assessment of the in vivo fertilizing capacity of ejaculated spermatozoa.

Cell Survival↗
PubMedDate not supplied

Acrosomeless sperm. A cause of primary male infertility.

Sperm without acrosome of two males--spouses of infertile marriages--were studied. No acrosome could be identified in the Papanicolaou stained smears of either patient. Electron microscopy study confirmed the absence of acrosome and post-acrosomal sheath. The physical and functional integrity of the sperm membrane was determined by vital staining technique (72% unstained) and hypoosmotic stress test (69% swollen). Acrosin assay showed a five-fold decrease, and proacrosin values were almost eight-fold lower than the normal values. Nonzymogen acrosin level was normal. Zone-free hamster oocytes were not penetrated by the acrosomeless sperm showing 46% progressive motility, but postcoital tests in both female spouses showed active sperm. The results would indicate that the sperm devoid of acrosome may be considered as a primary cause of male infertility.

Acrosin↗