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Biomedical subjects

G Paz

Publications and source records attributed to G Paz.

At least 91 records · Page 5Linked to original sources

The temperature, pH, and partial pressure of oxygen in the cervix and uterus of women and uterus of rats during the cycle.

Changes in the temperature, pH, and partial pressure of oxygen (PO2) in the cervical canal and cavum uteri were measured in women with or without an intrauterine device and in the uteri of rats throughout the cycle. Only the PO2 exhibited significant variations, rising during the ovulatory phase in both cervices of women and uteri in rats. It is speculated that the rise in PO2 is related to the function of these organs as reservoirs for spermatozoa.

Adult↗

Effect of caffeine on the motility, viability, oxygen consumption and glycolytic rate of ejaculated human normokinetic and hypokinetic spermatozoa.

In this report the effect of caffeine, IBMX and Cholera toxin on ejaculated human spermatozoa was tested. It was found that caffeine was the most effective drug, and that Cholera toxin was ineffective. Caffeine stimulated motility, preserved viability and increased the glucose, fructose utilization and lactate production of sperm in whole semen and washed sperm. Oxygen consumption however was decreased. These results of the normokinetic ejaculates were defined as a basis for comparison with the response of hypokinetic sperm. A group of 11 hypokinetic ejaculated spermatozoa were treated by caffeine and only five responded to caffeine stimulation by a response, similar to that of normokinetic sperm. They were defined as "responsive." The other group of six patients who did not respond were defined as a "non-responsive" class. The possibility that the in vitro treated sperm of the responsive class ejaculate is suitable for artificial insemination to their wives, is discussed.

Caffeine↗

Improvement of fertility and semen quality in men treated with a combination of anticongestive and antibiotic drugs.

The effects of a combined therapy of antibiotics and antiinflammatory drugs was evaluated in 344 men referred to our clinic for treatment of infertility. Physical signs of congestion, usually not severe, were detected in 244 men. The treatment caused significant improvement in semen quality, especially in sperm concentration, morphology and motility. Forty percent of the wives became pregnant. There was a striking relationship between increase in morphologically normal spermatozoa and incidence of pregnancy. It is speculated that the therapy had its major effect at the level of the epididymis and/or testis.

Adult↗

The expression of mannose-ligand receptor is correlated with sperm morphology.

The objective of the present study was to evaluate the association between the expression of sperm mannose-ligand receptors and sperm morphology. Sperm samples were obtained from 45 men, 30 fertile sperm donors and 15 infertile men. Sperm concentration, motility and morphology were evaluated and then incubated with control medium (Ham's F-10 + 1% HSA) for 4 h. Expression of mannose-ligand receptors was evaluated by mannosylated-BSA-FITC (subdivided into 3 patterns: I, for uncapacitated sperm; II, for capacitated; and III, for acrosome-reacted sperm). The mean (+/- SE) frequencies of sperm cells of the total sperm population that expressed patterns I, II, and III were 88 +/- 2.1%, 7 +/- 1.6%, and 5 +/- 0.8%, respectively, for fertile men, and 90 +/- 2.1%, 7 +/- 1.3%, and 3 +/- 0.5%, respectively, for infertile men. The rate of pattern III expression of mannose-ligand receptors was significantly higher in the fertile group compared to the infertile patients (p <.01). A poor but significant correlation was observed between the rate of pattern III and the percentage of normal-forms sperm cell in the ejaculate (r =.35, p =.018). Fertile sperm samples express more advanced patterns of mannose-ligand receptors compared to infertile men. This phenomenon is related to the morphology of human sperm cell in the ejaculate more than to any other basic sperm characteristics.

Humans↗

Improvement in the cervical mucus penetration test by using standard sperm control.

The objective of the present experiments was to establish an acceptable standard for the cervical mucus penetration test (CMPT) by determining the minimal progressive motile spermatozoa concentration (PMSC) that will yield the highest score for proven fertile donor sperm specimens. For this purpose, fresh and frozen-thawed samples were used. Semen was obtained from 29 fertile donors and different PMSC (8, 10, and 14 x 10(6)/mL) were prepared for each sample. The same mucus specimen was used for testing each sperm sample in the three different dilutions. No difference in the scoring of the CMPT between the fresh vs. frozen-thawed groups was found. When PMSC of 14 x 10(6)/mL was used, almost all specimens scored the highest rank. The present study revealed that only semen samples with a minimal PMSC of 14 x 10(6)/mL cells can be used in the CMPT. The information that the freeze-thaw process does not affect the CMPT results supports the concept of cryopreservation of pooled fertile donor specimens in aliquots with adequate concentration of progressive motile spermatozoa for later use as a CMPT control.

Cervix Mucus↗

Varicocele: effect on sperm functions.

Despite the numerous studies published over the past decade, the role of varicocele in male infertility is still controversial. Although more frequent in infertile men, its influence on sperm production or function has not, as yet, been determined. Moreover, the exact mechanism of varicocele action is not clear. We have surveyed the literature, the correlation of varicocele to sperm parameters and to sperm function tests, such as binding capacity, hypo-osmotic swelling test, presence of reactive oxygen species, and in particular, the correlation to fertility potential. Almost every subject examined had contradictory results. Larger control studies may possibly elucidate and clarify the cases in which varicocele is associated to sperm function, and where treatment may improve fertility.

Acrosome Reaction↗

Intrauterine insemination in subfertile couples.

Forty-three subfertile women were treated by intrauterine insemination with washed sperm. Among the couples, infertility was, in 7 cases due to cervical factor infertility, in 17 cases due to subfertile sperm quality, and 19 cases, unexplained. All women ovulated: 9 spontaneously, 26 where treated with clomiphene citrate and 8 with hMG-hCG. One hundred and sixty seven inseminations were performed in 90 ovulatory cycles. Six pregnancies were recorded (14%): three pregnancies among the cervical factor infertility group (42.8%), two among the couples with low sperm quality (11.7%) and one pregnancy in the group with unexplained infertility (5.2%). Thus, it can be concluded that IUI is effective for achieving pregnancy when unfavourable cervical factor is detected. The method is of doubtful value in cases of low sperm quality or unexplained infertility.

Adult↗

Fertility of men following inguinal hernia repair.

Among 8500 patients attending the fertility clinic due to infertility, 565 men (6.65%) reported an incidence of inguinal hernioplasty with or without subsequent atrophy of the testis. Semen quality (sperm concentrations, motility, and morphology) of these patients was markedly reduced in comparison to that of fertile men. In cases where hernioplasty was followed by atrophy of the testis, damage to sperm characteristics and Sertoli cell function was found to be far greater. This was also reflected in significant serum follicle stimulating hormone elevation (P less than 0.0025). No changes in luteinizing hormone and testosterone were found. No correlation was found between age of hernioplasty and semen quality following operation. The reasons for testicular damage may be due to ischaemic orchitis or immunological reactions.

Adolescent↗

Cryptorchidism: incidence and sperm quality in infertile men.

In a population of 8500 men attending the andrology outpatient clinic, 200 men (2.35%) were recorded as having some disturbances with the descent of the testes into the scrotum. Medical history of the patients revealed that 51 underwent unilateral orchidopexy; 40 bilateral orchidopexy; and 24 were treated with human chorionic gonadotropin in order to induce descent of their testes. In addition, 6 patients reported spontaneous descent of the testes, and 13 others were found to be unilaterally cryptorchid upon physical examination. Results of semen analysis, hormonal profile, testes position, and testicular volume were compared to those of 105 proven fertile men. The major finding of this study shows that post-partum undescended testes suffer from primary Sertoli cell malfunction as reflected by elevated serum follicle stimulating hormone levels. Serum luteinizing hormone and testosterone levels were within the normal range. Surgical descent of the testes did not improve sperm production, proved by low sperm quality of all the study groups, compared to the cryptorchid group. Among the patients who were operated on, no correlation was found between age at operation and semen variables. All groups showed poor sperm quality which can be defined as oligoteratoasthenozoospermia. The degree of spermatogenic damage was in the following order of diagnosis or treatment: bilateral orchidopexy greater than cryptorchid testes greater than hormonal treatment greater than unilateral orchidopexy greater than late spontaneous descent of the testes. Thus, it is advisable to postpone surgical treatment of cryptorchidism and apply this only after a waiting period, and if the hormonal approach has failed to descend the testis.

Adolescent↗

Advanced methods for evaluation of sperm quality.

Routine semen analysis includes measurements of sperm concentration, motility, and morphology. In our study, three additional tests were evaluated in relation to fertilization rate in an in vitro fertilization program: the freezing and hypo-osmotic swelling tests that evaluate the functional integrity and stability of the sperm membrane under extreme osmotic conditions, and migration sedimentation test that isolates high-quality motile sperm cells. The study was performed on semen delivered by men of couples treated at the In Vitro Fertilization Unit, and men who served as semen donors (fresh or cryopreserved semen). No correlation was found between the sperm fertilization rate, and the decrease in motility percent following the freezing-thawing process. Thus, the freezing test cannot be used to predict semen fertilization capacity. The hypo-osmotic swelling test was applied on semen given by a similar population of men. While the hypo-osmotic swelling test values carried out with fresh semen was found to have good correlation with fertilization, no correlation was found when frozen thawed semen was used. Post-migration sedimentation test sperm characteristics, and especially the recovery rate of the motile sperm, were significantly better in in vitro fertilization cycles with fertilizations. Both the hypo-osmotic swelling test and migration sedimentation test can assist in evaluating semen quality, judged by the fertilization rate in an in vitro fertilization program.

Female↗

Sperm binding and ultrasound changes after operative repair of varicocele: correlation with fecundity.

The study was conducted to evaluate the changes in sperm binding capacity and ultrasound measurements of the internal spermatic vein, after operative repair of a varicocele. In order to clarify the effect of a varicocele on fertility, these changes were correlated to pregnancy achievement. Twelve infertile males with subnormal semen parameters and varicocele, underwent operative repair. Pre- and post-operatively, all had semen analysis, hemizona assay and ultrasound of the internal spermatic veins. The patients were divided into three subgroups according to pregnancy outcome, and the changes in the different evaluation tests after the operation were compared. Sperm concentration and motility improved post-operatively in all three subgroups, whereas the hemizona index and ultrasonographic measurements improved significantly only in the subgroup that achieved early pregnancies (the mean post-operative percentage of normal morphology was significantly higher), compared to the subgroup without pregnancies. Unlike sperm parameters which improve after operative repair of the varicocele, but have no correlation to conception, sperm binding and ultrasound measurements of the internal spermatic veins improve significantly in cases that achieve early pregnancies. The use of these tests, as well as measuring the percentage of normal morphology, are recommended in all cases of infertility-related varicocele.

Female↗

Correlation between sperm penetration into the human zona pellucida and in vitro fertilization rates.

Sperm penetration into the zona pellucida of unfertilized oocytes, and its correlation with in vitro fertilization rates of the sibling oocytes, were assessed. This was performed in order to evaluate the prediction rate of the sperm penetration test into the zona pellucida. Unfertilized oocytes (n = 1872) from 371 cycles were pipetted through a microcapillary, and the remaining sperm cells penetrating the zona pellucida were counted. The mean (+/- SD) number of spermatozoa that penetrated the zona pellucida of unfertilized oocytes was 12.9 +/- 16.37. A significant correlation was found between the fertilization rate and the mean number of spermatozoa that penetrated into the zona pellucida of the unfertilized sibling oocytes (r = 0.48; P < 0.001), or the percent of unpenetrated zonae pellucidae in a cohort (r = -0.43; P < 0.001). However, a distinct variation in the number of spermatozoa that penetrated into the zona pellucida was detected. A step-wise regression analysis proved the number of spermatozoa penetrating the zona pellucida to be more predictive for fertilization rates than the variable of percent of unpenetrated zonae pellucidae. The results imply that although there is interdependence between penetration into the zona pellucida and fertilization rate, the predictive value of sperm penetration test for prognosis and future management after the first in vitro fertilization attempt, is limited.

Cohort Studies↗

Effect of sperm preparation with TEST yolk buffer on sperm-binding capacity under hemizona assay conditions.

The study was conducted to evaluate the diverse effect and clinical significance of TEST yolk buffer treatment on sperm samples of 128 infertile men. Sperm samples were incubated with TEST yolk buffer and control medium (Ham's F-10) at room temperature for 2 h. The hemizona indices (mean +/- SE) of the TEST yolk buffer and medium-treated sperm samples were 29 +/- 2.3% and 22 +/- 1.6%, respectively. Inspection of the individual response of each sperm sample to TEST yolk buffer revealed that 63 samples (49%) improved (double the interassay variation = 28%) their binding to zona pellucida, 36 (28%) remained unchanged, whereas the binding capacity of 29 samples (23%) decreased. Furthermore, TEST yolk buffer treatment of 24 samples (19%) resulted in an increased binding beyond the hemizona index threshold set up at 23%. This level was previously shown to be the cut-off point between fertile and infertile sperm samples. It was concluded that when applied to an unselected group of infertile men, TEST yolk buffer significantly increased sperm binding capacity to the zona pellucida. However, only 19% of the sperm samples showed improvement with clinical significance. The other sperm samples may have improved, remained unchanged or even deteriorated independently on basic sperm variables. Thus, the effect of TEST yolk buffer treatment on sperm binding should be tested prior to its clinical use to avoid possible damage to certain sperm samples.

Buffers↗