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T F Kruger

Publications and source records attributed to T F Kruger.

At least 73 records · Page 4Linked to original sources
PubMed1991

Defining the valid hemizona assay: accounting for binding variability within zonae pellucidae and within semen samples from fertile males.

OBJECTIVE: To achieve a better understanding of the variability in sperm and oocyte binding capacities will optimize use of the hemizona assay (HZA) as a predictor of sperm function. DESIGN: Limitations of the HZA were more clearly delineated by current studies: (1) variability of sperm binding capacity of men over a 90-day interval; (2) variability of sperm binding using different oocytes; and (3) lower limits of the number of sperm bound from the fertile control in two laboratories. PATIENTS: Semen was obtained from proven fertile men and one subfertile individual. MAIN OUTCOME MEASURE: The number of sperm tightly bound to the hemizona were measured and compared. RESULTS: In the initial study, 6 fertile control men exhibited a similar degree of variability in zona binding when studied over a 90-day interval. Average sperm binding for individuals ranged from 68 to 127. Second, 3 of the 15 simultaneous assays showed very low numbers of sperm bound, indicating that 20% of the zonae had poor binding. Third, from 18 men who had 0% fertilization in an in vitro fertilization system using mature oocytes, evaluation of their sperm by HZA was performed. The sperm bound poorly and the 95% confidence interval was 20 sperm bound. Thus, the fertile controls should bind greater than 20 sperm to distinguish them from the infertile group in the HZA system resulting in a valid assay. CONCLUSIONS: With these guidelines, applications of the HZA may be made with greater reassurance of a valid bioassay of sperm fertilizing potential.

Biological Assay↗
PubMed1990

Genital tuberculosis associated with female infertility in the western Cape.

Infertility is a common presenting symptom in women with genital tuberculosis. A study was undertaken to determine the prevalence and characteristics of this disease among the infertile patients (A and B income group) attending the Reproductive Biology Unit at Tygerberg Hospital. Between June 1986 and December 1987, the menstrual fluid from 451 infertile women was cultured for Mycobacterium tuberculosis using Löwenstein-Jensen medium. A prevalence of 7.98% (36/451) was found. Laparoscopic examination of the pelvis revealed bilateral tubal occlusion in 3 patients (8.3%); peritubular adhesions were present in 17 patients (47.2%). In the remaining 16 patients (44.5%), the pelvis was considered normal. No culture-positive patient gave a history of previous infection or contact with tuberculosis. Radiography of the chest and histological examination of the endometrium showed no evidence of infection. Of the 34 patients treated, 13 (38.2%) became pregnant after antituberculosis treatment was completed. If tuberculosis occurs in a population, menstrual fluid of infertile women should be cultured routinely for M. tuberculosis, especially if there is evidence of tubal damage.

Adolescent↗
PubMed1990

The in vitro fertilisation programme at Tygerberg Hospital and the University of Stellenbosch. Five years' experience, April 1983-January 1988.

The results of the in vitro fertilisation programme at Tygerberg Hospital for the period April 1983 to January 1988 are presented. Of the 1117 laparoscopies performed, 825 patients reached the transfer stage. A live-birth rate of 9.3% was achieved. The pregnancy rate after transfer of 4 embryos was 25.9% compared with 15.4% after 2 embryos and 10.8% after 3 embryos (P = less than 0.0001). The multiple pregnancy rate was 2.8% in the group receiving 2 embryos and 11.7% and 10.4% in those receiving 3 and 4 embryos, respectively. Of the 77 successful pregnancies (90 babies), 1 baby died at 34 weeks' gestation as the result of abruptio placentae due to preeclampsia and 1 cot death occurred. The only congenital abnormality encountered was a cleft palate.

Female↗
PubMed1990

Treatment of male sperm autoimmunity by using the gamete intrafallopian transfer procedure with washed spermatozoa.

Sixteen couples were diagnosed as having immunological infertility. To detect sperm-bound immunoglobulin (Ig), i.e., IgA, IgG, and IgM antibodies, the direct immunobead test (IBT) was used. In each individual patient, the direct IBT was greater than or equal to 70% positive for either IgA or IgG or both. The indirect IBT was positive for IgA and IgG antibodies in the serum of all the patients. Semen was collected in 15 mL medium (Ham's F10 [Gibco, Grand Island, NY] + 10% whole blood serum) and prepared with the wash and swim-up method. Patients in the study group were treated for their immunological infertility problem by performing the gamete intrafallopian transfer (GIFT) procedure. An ongoing pregnancy was achieved in 7 of the 16 (43%) couples treated with the GIFT procedure with an ongoing pregnancy rate of 24.1% (7 of 29) per cycle. The GIFT procedure appears to be an effective and safe way of treating male immunological infertility.

Autoantibodies↗
PubMed1990

Gamete intrafallopian transfer as treatment for infertility associated with endometriosis.

Forty-six patients with endometriosis-associated infertility underwent 59 GIFT cycles. The pregnancy rate per cycle was 30.5%. The presence of endometriomas in 11 patients did not affect this rate adversely. We conclude that, provided at least one fallopian tube is patent, GIFT compensates effectively for the possible causes of infertility in these patients.

Adult↗
PubMed1990

Hemizona assay and teratozoospermia: increasing sperm insemination concentrations to enhance zona pellucida binding.

This study aimed: (1) to evaluate the zona-binding capacity of patients with abnormal sperm morphology, using standard hemizona assay (HZA) conditions and increasing sperm insemination concentration during the assay and (2) to determine the insemination concentration needed to obtain equality in the number of tightly bound sperm to matching hemizonae, using sperm from teratozoospermic patients versus proven fertile controls. The minimum concentration of motile sperm from fertile controls necessary to validate HZA results was 250,000/mL (35.4 +/- 5.6 tightly bound sperm; mean +/- SE). The "effective number of sperm" (morphologically normal with high motility) was 60,750/mL. Each teratozoospermic patient had a unique, (higher) sperm insemination concentration (range: 0.5 X 10(6) to 2.0 X 10(6) motile sperm/mL) necessary to equal the number of tightly bound sperm representing the lower 95% confidence interval for the control sample (at 0.5 X 10(6) motile sperm/mL) with the matching hemizona. These results suggest that the HZA may be used as an indicator of the sperm insemination concentration during in vitro fertilization in patients with teratozoospermia.

Female↗
PubMed1990

The evaluation of morphological characteristics of human spermatozoa according to stricter criteria.

The evaluation of the morphology of human spermatozoa varies widely between and sometimes even within laboratories. The purpose of this study was to determine whether the method that has been developed in our laboratory and which resulted in the use of stricter criteria for the evaluation of sperm morphology is a practical, reliable and repeatable method and to establish the within and between observer variations. The criteria used for a 'normal' spermatozoon are based on the appearance of spermatozoa found in the mucus of the upper endocervical canal. The results of the morphological evaluations of 26 samples by four observers were statistically analysed by various methods. The method of Barnett showed a high degree of relative accuracy between observers with error variances of between 2.89 and 19.67 as well as high Spearman rank correlation coefficients of between 0.8675 and 0.6537 (P less than 0.0003). The Spearman correlation coefficient for 15 duplicate evaluations by one observer was 0.9650 (P less than 0.0001) while the coefficients of variation for repeated evaluations of single samples were also within acceptable limits. Based on these results, the method described in this article allows comparable and reliable results between and within observers to be obtained. From this and other studies it can be concluded that the method also has a good prognostic value for the prediction of expected IVF fertilization, the hamster test and hemizona assay.

Cytodiagnosis↗
PubMed1989

Human pregnancy after transfer of intact frozen-thawed embryos.

Since the birth of the first baby as a result of in vitro fertilisation (IVF) in 1978, many clinics around the world have achieved pregnancies and births for their patients by using IVF and gamete intrafallopian transfer procedures. With the storage of excess embryos, multiple laparoscopies can be avoided; this has favoured the development of better cryopreservation techniques. In our clinic 8-cell human embryos are frozen in a 1.5M dimethyl sulphoxide solution as cryoprotectant using the slow freeze-thaw method. Sixteen thawed embryos were replaced in 8 patients, resulting in 1 pregnancy. Of the thawed embryos 51.6% survived the freezing process in that they had 50% or more of the original number of blastomeres and also the zona pellucida intact.

Cryopreservation↗
PubMed1989

Hemizona assay using salt-stored human oocytes: evaluation of zona pellucida capacity for binding human spermatozoa.

Human oocytes were stored (25 degrees C) in 1.5 M MgCl2 for 6-30 days, then utilized in the new hemizona assay (HZA) for tight binding of human spermatozoa [Burkman et al.: Fertil Steril 49:688-697, 1988]. We have compared 1) the ability of matching salt-treated hemizonae or dimethylsulfoxide (DMSO)-treated hemizonae to distinguish between sperm from semen having normal versus subnormal characteristics and, 2) the kinetics of fertile sperm binding to salt-treated or DMSO-treated hemizonae. After sperm preparation one salt-treated hemizona was incubated with normal spermatozoa and the matching hemizona was placed with sperm from the subnormal group. As a control, DMSO-treated hemizonae were incubated in additional sperm droplets. After 4 hours, the number of sperm tightly bound to each hemizona was counted. Within the normal semen group, there was equivalent binding to salt- or DMSO-treated hemizonae (54.0 +/- 12 and 49 +/- 14, respectively, mean +/- SEM). Similarly, tight binding of sperm from the subnormal group was not affected by the zona storage method (21 +/- 8 and 17 +/- 5, respectively). For either storage approach, binding of subnormal sperm was significantly less (P less than 0.01) compared with the number of normal sperm attached to the matching hemizona. For the kinetics study, the hemizona binding of proven fertile spermatozoa was followed throughout 8.5 hours. The shape of the binding curve was the same for zonae stored by either method and was consistent with our published kinetics data. Salt storage offers a simple and inexpensive means for accumulating and transporting human zonae pellucida; the resulting hemizonae function effectively in the HZA for estimating sperm binding potential.

Dimethyl Sulfoxide↗
PubMed1989

The hemizona assay (HZA): a predictor of human sperm fertilizing potential in in vitro fertilization (IVF) treatment.

The hemizona assay (HZA) was developed to assess human sperm fertilizing potential. This blinded study investigated the relationship between sperm binding to the hemizona and in vitro fertilization (IVF) success (36 patients). Nonliving human oocytes were recovered from excised ovaries and stored. Each zona pellucida was cut into equal hemispheres by micromanipulation. For the HZA, one droplet exposed a hemizona to abnormal spermatozoa, while the control droplet contained the matching hemizona and spermatozoa from normal semen. After 4 hr, the number of tightly bound spermatozoa was counted. Binding to the hemizona was significantly higher for those having IVF success (mean of 36.1 +/- 7, versus 10.4 +/- 4 from the failure group; P less than 0.05). Fewer sperm from the failure group had a strictly normal morphology (3.2 versus 12.7%; P less than 0.05, Kruger method). Tight zona binding was significantly correlated with the percentage motile sperm, percentage normal morphology, and seminal sperm concentration. These results enhanced our confidence that the HZA is diagnostic for identification of patients at high risk of failing to achieve fertilization in vitro.

Female↗
PubMed1989

Use of specific monoclonal antibodies to secretory IgA for the detection of spermatozoal antibodies in serum and seminal plasma by enzyme-linked immunosorbent assay.

The role of anti-sperm secretory IgA has recently received attention since some workers feel it plays an important role in the prognosis of the immunologically infertile couple. Current methods used in our laboratory cannot separately detect anti-sperm secretory IgA. An enzyme-linked immunosorbent assay (ELISA) utilizing specific monoclonal antibodies to secretory IgA was used to detect anti-sperm secretory IgA as well as anti-sperm monomeric IgA and IgG in serum and seminal plasma of a sperm-antibody-positive (ASA+) and sperm-antibody-negative (ASA-) group of men. Results showed significantly raised serum levels in the ASA+ group when compared to the ASA- group for anti-sperm secretory IgA (P less than .001), anti-sperm monomeric IgA (P less than .001), and anti-sperm IgG (P less than .01). Seminal plasma levels were also raised in the ASA+ group, but only significantly so for monomeric IgA (P less than .02). The performed ELISA has definite potential in research, especially with the use of monoclonal antibodies for the detection of anti-sperm secretory IgA, but cannot as yet be used as a prognostic predictor of fertility in the individual antibody-positive patient. Infertility specific antigens will have to be identified and isolated and subsequently used in the ELISA.

Antibodies, Anti-Idiotypic↗
PubMed1989

Effect of sperm washing and swim-up on antibodies bound to sperm membrane: use of immunobead/sperm cervical mucus contact tests.

The direct immunobead test (IBT) and the sperm cervical mucus contact (SCMC) test were used to evaluate the effect of sperm washes and swim-up on antibodies bound to the sperm membrane in 11 patients with autosperm antibodies (30-100% IgA and 30-100% IgG) but otherwise normal semen measurements. The tests were performed on semen samples before and after a wash/swim-up procedure in Ham F10 + 10% human blood serum. Sperm-bound antibodies in washed spermatozoa that were able to swim into a layer of medium did not differ from those in unwashed samples. The IBT and the SCMC test on unwashed and washed spermatozoa were also not significantly different. However, all other washed semen parameters were improved. Correct washing of semen samples is important when performing the IBT to prevent false negative results. Eight of the 11 partners (73%) of the patients tested became pregnant after treatment with washed sperm. The ongoing pregnancy rate was 64%.

Animals↗
PubMed1989

Effect of rapid dilution of semen on sperm-bound autoantibodies.

The effect of rapid dilution of autoantibody-positive semen on sperm-bound antibodies was studied in 12 male patients (0-100% IgA and 10-100% IgG). The direct immunobead test (IBT) and the sperm cervical mucus contact (SCMC) test were used to detect sperm-bound antibodies on spermatozoa before and after rapid dilution and swim up in HAM F-10 + 10% human blood serum. All patients tested had normal semen parameters. Sperm-bound antibodies detected after swim-up of semen samples ejaculated into 15 ml HAM F-10 + 10% serum (diluted) did not differ significantly from undiluted samples. Most values were lower (IBT and SCMC) but were not statistically significant. Sperm motility, forward progression, and morphology were statistically improved. Pregnancies resulting from washed semen (diluted) in combination with artificial insemination (AIH) or gamete intrafallopian tube transfer (GIFT) took place in spite of antibodies still present on the sperm membrane and can probably be attributed to improved semen quality, minimizing of ovum-sperm distance, and cervical mucus elimination.

Autoantibodies↗
PubMed1989

Does the wash-up and swim-up method of semen preparation play a role in sex selection?

Because of the higher built ratio of boys to girls (1.5 : 1) by in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT) at Tygerberg Hospital, the question arose as to whether the wash-up and swim-up method of semen preparation, used for our IVF procedure, plays a role in sex selection. Semen samples of 20 men were evaluated at different time intervals to determine the percentage of F-body-positive spermatozoa. It was found that the swim-up time affects the relationship between Y- and X-bearing spermatozoa, especially at time intervals of 30 and 45 min, where an optimum percentage of Y-bearing spermatozoa (p = 0.0039 and p = 0.0092, respectively) was found. Sperm obtained at these specific time intervals may influence the outcome of sex by IVF and GIFT in favor of males.

Fertilization in Vitro↗
PubMed1989

Hypoosmotic swelling test in the prediction of male fertility.

The hypoosmotic swelling test (HOS) is a simple test to measure the functional competence of human sperm membranes. The question is, does a relationship exist between this competence and the fertilization potential of human spermatozoa? In this study the strongest correlation (r = 0.76) was obtained between sperm swelling and sperm viability (supravital staining). Only a moderate correlation (r = 0.50) was obtained with normal sperm morphology; weaker correlations were also obtained with the sperm penetration assay (r = 0.42) and human IVF (r = 0.24). The results, therefore, indicate that the HOS test has a limited predictive value. Notwithstanding this low concordance between sperm swelling and fertilizing potential, a less than 50% HOS test threshold was seen to be a definite indicator of a male factor.

Cell Survival↗
PubMed1989

Antisperm antibody tests: traditional methods compared to ELISA.

Enzyme-linked immunosorbent assays (ELISAs) to detect sperm antibodies can be a useful addition to other tests. ELISAs allow more quantitative and detailed information than some other tests, but results should be compared to those of other tests. This study was conducted to correlate results of an ELISA that used a sperm membrane extract as antigen with those of other tests. Semen, seminal plasma, and serum of 34 sperm-antibody-positive and 36 sperm-antibody-negative men were tested. There was poor correlation between the ELISA results and those of the other tests. Only the results of a direct immunobead test done on semen correlated fairly well with results from ELISAs done on serum. Further studies are needed on fertility-specific antigens that can be identified and isolated and then studied by means of ELISAs.

Antibodies↗
PubMed1989

Usefulness of sperm penetration assay in fertility predictions.

The competence of the sperm penetration assay (SPA) to predict male fertility, as determined by normal sperm morphology and the fertilizing potential, as shown by human in vitro fertilization (IVF), was investigated. A significant correlation was obtained between normal sperm morphology and the SPA (phi = 0.623). A weaker correlation was however obtained with human IVF (phi = 0.397). Notwithstanding this weak association, a positive SPA (greater than 10%) was highly predictive (95%) of human IVF success. In contrast, a negative SPA (less than or equal to 10%) was associated with a high rate of false-negatives (65%). The SPA does however warn that a male factor may be present, as the mean fertilization rate of this group of patients was markedly reduced. The preincubation period for the spermatozoa did not play a major role in the predictive ability of a SPA outcome.

Female↗