Marvellous ICSI: the viewpoint of a clinician.
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Humans↗
Biomedical subjects
H W Baker
Publications and source records attributed to H W Baker.
Calcium ionophore-induced acrosome reaction correlates with fertilization rates in vitro in patients with teratozoospermic semen.
The aim of this study was to determine the relationship between calcium ionophore A23187-induced acrosome reaction (AR) and sperm fertilizing ability. Semen samples remaining after preparation for standard IVF were studied in 109 patients who had sperm concentrations > or =20 x 10(6)/ml. Ionophore-induced AR was performed on motile spermatozoa selected by centrifugation on a Percoll gradient. Semen analysis was performed using standard methods. Patients with higher (>50%, n = 76) fertilization rates had significantly higher ionophore-induced AR than patients with lower (<50%, n = 33) fertilization rates (49 +/- 14 versus 38 +/- 21%, P < 0.05). When the data from all patients were analysed by logistic regression, only the percentage sperm motility in insemination medium and ionophore-induced AR were significantly related to fertilization rates. Similar results were also obtained when the data from a subgroup of patients with poor (<15% normal) sperm morphology were analysed. However, when patients with normal sperm morphology > or =15% were analysed separately, only sperm count and the percentage of spermatozoa with progressive motility in semen were significantly related to fertilization rates. In conclusion, ionophore-induced AR was significantly related to fertilization rates in vitro mainly in patients with teratozoospermic semen. Tests for ionophore-induced AR may provide additional information about sperm fertilizing ability but may not indicate specific defects of the physiological AR.
Calcimycin↗
Quantitative sperm mucus penetration: modified formulae for calculating penetration efficiency.
In 1980 Katz et al. derived a formula for the percentage of successful collisions (PSC) as a quantitative measure of sperm-cervical mucus penetration efficiency. The use of PSC waned after its validity was questioned by reports of values >100% and the observation that PSC varied with the cross-sectional area of the mucus column. The aim of the present study was to develop a more accurate measure of mucus penetration efficiency by correcting the original formula for the effects of sperm depletion in the semen reservoir. Two formulae were derived using different models for the sperm-mucus interaction: (i) each motile spermatozoon was assumed to have an equal chance of mucus penetration on collision; (ii) a select subpopulation of spermatozoa was assumed to penetrate with 100% efficiency on collision. Both modified formulae gave PSC values higher than the original estimates. Under the experimental conditions employed in this work, where large capillaries were used, the depletion corrections ranged from 4 to 46% (n=8, mean 20%) for model (i) and from 190 to 320% (n=8, mean 250%) for model (ii). The invariance of PSC (ii) results with respect to capillary cross-sectional area (1.52 mm2, 31.1%; 5.4 mm2, 28.2%) suggests that the assumptions of model (ii) provide the more accurate description of the sperm-mucus interaction.
Female↗
Corticosteroid-induced bone loss in men.
Lack of consistent information concerning the pathophysiology of corticosteroid-related bone loss may be due to coexisting independent factors that influence bone mineral density (BMD). For example, the disease being treated may increase bone turnover and cause bone loss, and its severity may influence the dose of corticosteroids chosen. Similarly, disease remission due to the treatment or disease progression despite treatment may influence bone turnover and the rate of bone loss. The hormonal changes purportedly responsible for reduced bone formation or increased bone resorption may be the result of the disease, not the corticosteroids. To determine the pathophysiology of corticosteroid-related bone loss, we conducted a controlled, prospective study in men with no systemic illness treated with corticosteroids to reduce antisperm antibodies. We measured BMD using dual x-ray absorptiometry and circulating biochemical and hormonal determinants of bone turnover in 9 men before and during prednisolone treatment and in 10 age-matched controls. The results were expressed as the mean +/- SEM. There were no differences in BMD between the two groups at baseline. The patients received 50 mg prednisolone daily for 3.7 +/- 0.6 months (range, 1-6). BMD decreased by 4.6 +/- 0.8% at the lumbar spine (P = 0.0007), by 2.6 +/- 0.6% at the trochanter (P = 0.004), and by 4.8 +/- 1.9% at the Ward's triangle (P < 0.04). The decrease in lumbar spine BMD correlated with the cumulative dose of corticosteroids (r = -0.49; P = 0.03). Serum osteocalcin and skeletal alkaline phosphatase decreased by 28.5 +/- 15.5% (P = 0.08) and 24.2 +/- 8.6% (P < 0.03), respectively. The decrease in lumbar spine BMD correlated with the decrease in osteocalcin (r = -0.48; P < 0.02). Serum testosterone and sex hormone-binding globulin decreased by 28.6 +/- 4.4% (P < 0.003) and 28.5 +/- 8.3% (P < 0.007), respectively. The testosterone/sex hormone-binding globulin ratio did not change. The decrease in total testosterone correlated with the decrease in osteocalcin (r = -0.40; P = 0.05). There were no detectable changes in urinary C-telopeptide, serum PTH, or serum calcium. Estradiol decreased by 23.5 +/- 11.4% (P < 0.003). Corticosteroid therapy results in rapid bone loss, probably due to reduced bone formation. Neither increased bone resorption nor secondary hyperparathyroidism appears to contribute to the rapid bone loss. Whether the reduction in bone formation may be partly mediated by changes in sex steroids remains unclear.
Absorptiometry, Photon↗
Testicular and epididymal sperm in a microinjection program: methods of retrieval and results.
OBJECTIVE: To describe the methods of collection and laboratory preparation of epididymal and testicular sperm; to compare the fertilization and pregnancy rates; and to establish prognostic factors. DESIGN: Retrospective analysis. SETTING: Academic reproductive medicine clinic. PATIENT(S): One hundred twelve consecutive microinjection cycles in 80 patients using either epididymal or testicular sperm. INTERVENTION(S): Sperm were collected by microepididymal sperm aspiration, open testicular biopsy, or fine needle tissue aspiration testicular biopsy. MAIN OUTCOME MEASURE(S): Fertilization rate, implantation, and clinical pregnancy rates. RESULT(S): The fertilization rate was higher with epididymal sperm (67%) than with testicular sperm (50%). Implantation rates (fetal hearts per embryo, testicular: 11%, epididymal: 8%) and pregnancy rates (clinical pregnancy per oocyte collection procedure, testicular: 25%, epididymal: 29%) were not significantly different with epididymal and testicular sperm. Multiple regression analysis showed that normal fertilization rates were significantly lower with testicular sperm, immotile sperm, and severe spermatogenic disorders. CONCLUSION(S): Although fertilization rates are significantly lower with testicular sperm, higher implantation rates resulted in equivalent pregnancy rates. Thus, testicular aspiration of sperm for intracytoplasmic sperm injection is a simple, inexpensive method of sperm retrieval in cases of azoospermia resulting from genital tract obstruction or severe spermatogenic disorder.
Biopsy↗
High fertilization and pregnancy rates after intracytoplasmic sperm injection in patients with disordered zona pellucida-induced acrosome reaction.
OBJECTIVE: To determine whether intracytoplasmic sperm injection (ICSI) is effective treatment for patients with disordered zona pellucida (ZP)-induced acrosome reaction (AR) who have failure of standard IVF-ET. DESIGN: Tests of sperm-ZP binding and penetration and the ZP-induced AR were used to diagnose patients with disordered ZP-induced AR who then were treated with ICSI. SETTING: Academic reproductive medicine research laboratory associated with a tertiary referral infertility clinic. MAIN OUTCOME MEASURE(S): Clinical features and results of previous IVF-ET, semen analysis and sperm-ZP interaction tests, and ICSI were analyzed. RESULT(S): The majority of patients had consistently normal sperm characteristics and all patients had normal sperm-ZP binding but failure of sperm-ZP penetration. The AR of sperm bound to the ZP was significantly lower in the patients (mean 6%, range 0% to 16%) than in the fertile men (mean 61%, range 27% to 96%). Intracytoplasmic sperm injection was performed on 34 patients and the normal fertilization rate averaged 73% per injected oocyte. Five ongoing and eight term pregnancies including two with twins were achieved after an average of two ET procedures per patient were performed. Two couples have second ongoing pregnancies from transfer of frozen embryos after successful first pregnancies. Overall, the implantation rate was 10.5% per embryo and the pregnancy rate 19% per ET and 38% per patient. CONCLUSION(S): Disordered ZP-induced AR is a cause of severe infertility and persistent failure of IVF-ET. Intracytoplasmic sperm injection is effective treatment for this condition. Patients with idiopathic infertility should be tested for this condition before commencing IVF-ET treatment.
Acrosome↗
The effect of 12-myristate 13-acetate phorbol ester on human sperm hyperactivation.
OBJECTIVE: To determine whether 12-myristate 13-acetate phorbol ester (PMA) can increase hyperactivated motility of human sperm. DESIGN: A controlled pharmacological study using computer-assisted semen analysis. SETTING: Andrology laboratory in a medical research institution. PATIENT(S): Normal semen was obtained from 48 men. INTERVENTION(S): Washed sperm were exposed to different concentrations of PMA alone or with P and pentoxifylline (PTX) for up to 2 hours and sperm motility measured by a computer-assisted semen analyzer. MAIN OUTCOME MEASURE(S): The percentage of sperm with hyperactivated motility was determined from the motility parameters: curvilinear velocity, linearity, and maximum amplitude of lateral head displacement. RESULT(S): Phorbol ester PMA increased hyperactivated motility in a dose- and time-dependent manner. At 1 hour, the average increases in hyperactivated motility were as follows: 2 microM, 4.8% +/- 1.5%; 6 microM, 9.6% +/- 1.5%; and 20 microM, 11.3% +/- 2.2%. The PMA effect was not altered when P or PTX were added although each separately had a positive effect on hyperactivation. CONCLUSION(S): Phorbol ester PMA stimulates human sperm hyperactivated motility, indicating the involvement of protein kinase C in the signal transduction pathway.
Humans↗
Intracytoplasmic sperm injection for treating infertility associated with sperm autoimmunity.
OBJECTIVE: To determine whether intracytoplasmic sperm injection (ICSI) can be used to achieve normal fertilization, embryo cleavage, and pregnancies in cases of sperm autoimmunity. DESIGN: A retrospective analysis of ICSI results in sperm antibody-positive and randomly selected antibody-negative groups. SETTING: University- and hospital-based reproductive research laboratory and tertiary referral IVF program. PATIENT(S): Thirty-nine couples selected on the basis of a strongly positive result for sperm antibodies of immunoglobulin (Ig) G and/or IgA immunoglobulin class in the male partner and a control group of 140 antibody-negative couples. INTERVENTION(S): Human menopausal gonadotropin, hCG and Lucrin (Abbott Australasia, Kurnell, NSW, Australia) were given by injection. Oocyte collection was by transvaginal ovarian puncture. Blood was collected for beta-hCG measurement. MAIN OUTCOME MEASURE(S): Normal fertilization, embryo cleavage, establishment of clinical pregnancy, and delivery. RESULT(S): There were no significant differences in fertilization rates (62% versus 58%) or clinical pregnancy rates (19% versus 12%) between sperm antibody-positive and sperm antibody-negative patient groups. CONCLUSION: Intracytoplasmic sperm injection is an effective treatment for patients with severe sperm autoimmunity.
Autoantibodies↗
Selectivity of the human sperm-zona pellucida binding process to sperm head morphometry.
OBJECTIVE: To obtain quantitative measures of morphometric selectivity of the human spermzona pellucida binding process as determined by light microscopy. DESIGN: Fully automated sperm head morphometric based on a 32-dimensional parameterization of images of Shorr-stained sperm. Zona pellucida selected sperm removed from reinseminated oocytes that previously failed IVF. SETTING: Academic research group associated with a tertiary infertility service. PATIENT(S): Semen samples from 51 infertile patients. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Differences in morphometric parameter means observed before and after swim-up and binding to zonae pellucidae. RESULT(S): Significant differences between insemination and bound sperm were observed in 17 parameter means and 21 standard deviations. The sperm-zona pellucida binding process preferentially selects sperm heads with a large anterior region with relatively low optical density, as well as high axial symmetry and minimal neck anomalies. Bias against sperm with pyriform morphology was not observed. CONCLUSION(S): A causal link has been established between sperm head morphometry, particularly within the acrosomal region, and the ability of sperm to bind to the human zona pellucida. As sperm-zona binding is necessary for fertility, it is possible to derive a physiologically based assessment for clinical diagnosis of male infertility using the "zona-preferred" morphometry results.
Acrosome↗
Medical treatment for idiopathic male infertility: is it curative or palliative?
Medical treatment of disorders of sperm production and function remains an important goal despite major advances in assisted reproductive technology. Effective treatments exist for genital tract obstruction, gonadotrophin deficiency, sperm autoimmunity, coital disorders and some impairments caused by toxins or illness. However, the majority of men seen for reduced sperm production or function do not have these conditions and the empirical treatments used in the past are probably ineffective. New therapeutic approaches derived from research on the causes and mechanisms of testicular dysfunction are needed and their curative effects must be established by well-designed controlled clinical trials.
Clinical Trials as Topic↗
Delivery of normal twins following the intracytoplasmic injection of spermatozoa from a patient with 47,XXY Klinefelter's syndrome.
Klinefelter's syndrome is a disorder of gonadal development and typically reveals a 47,XXY karyotype although mosaic forms also occur. Azoospermia is a common feature, but severe oligozoospermia and fertility have been reported. In this study, we have used intracytoplasmic sperm injection (ICSI) to achieve a live twin birth using spermatozoa from a 47,XXY man who has occasional spermatozoa present in the ejaculate. Spermatozoa were obtained from multiple ejaculates and frozen prior to commencing IVF treatment. Nine good quality embryos developed from the injection of 13 oocytes. All nine embryos were frozen. The initial transfer of two frozen-thawed embryos was unsuccessful. In the following cycle, the transfer of two additional frozen-thawed embryos resulted in the delivery of normal, healthy male and female twins. Five embryos remain frozen. It has generally been thought that the germ cells of 47,XXY men are unable to proceed through meiosis. Any spermatozoa produced have been assumed to come from a normal germ cell and therefore likely to have a normal karyotype. However, recent evidence suggests that meiosis of 47,XXY germ cells may be possible. Whether spermatozoa in these men arise from meiosis of 47,XXY germ cells, or from germ cells which have attained a normal karyotype by loss of an X chromosome, is unclear. Any risks in using spermatozoa from these patients have not yet been established. Patients need to be advised accordingly, and preimplantation or prenatal diagnosis should be considered. A cautious approach to the treatment of these patients is therefore warranted.
Adult↗
Immunosuppressive activities in the seminal plasma of infertile men: relationship to sperm antibodies and autoimmunity.
Semen samples from infertile men were assessed for sperm autoimmunity by direct immunobead assay for immunoglobulin (Ig)A and IgG sperm antibodies and mucus penetration test. Immunosuppressive activity in seminal plasma was measured by an in-vitro bioassay employing dose-dependent inhibition of phytohaemagglutinin-induced activation of rat thymocytes, in the presence or absence of hydroxylamine (0.1 mM), an inhibitor of polyamine oxidation. All seminal plasma samples, regardless of autoimmune status, caused inhibition of T-lymphocyte activation, and hydroxylamine reduced this bioactivity by appproximately 50%. Dialysis (<3500 molecular weight) also significantly reduced seminal plasma bioactivity, both in the presence and absence of hydroxylamine. In the presence of hydroxylamine, there was a negative correlation between IgA, but not IgG, antibody concentrations and lymphosuppressive activity in seminal plasma. Antibody-positive samples displaying impaired sperm function, as indicated by the mucus penetration test, had reduced activity compared with other samples. In contrast, there was no relationship between sperm autoimmunity and lymphosuppressive activity assayed in the absence of hydroxylamine. The data indicate that T-lymphocyte inhibition by human seminal plasma is due to multiple factors, and reduced amounts of these factors may contribute to the development and/or persistence of sperm autoimmunity in infertile men; however, differences in polyamine substrates available for oxidation in semen do not appear to be a major contributing factor.
Animals↗
Artificial insemination and in-vitro fertilization using donor spermatozoa: a report on 15 years of experience.
Donor insemination (DI) using cryopreserved semen commenced at The Royal Women's Hospital in 1976. Over the next 15 years we performed 5953 treatment cycles to achieve 816 pregnancies (13.7% per cycle) and 706 live births. In-vitro fertilization (IVF) using donor spermatozoa commenced in 1986. Over the next 5 years we performed 303 treatment cycles for 185 couples. Including subsequent transfer of cryopreserved embryos, a total of 33% of couples achieved a successful pregnancy by IVF. Statistical analysis indicated that, for DI pregnancies, the most important semen variable was the percentage post-thaw motility, whilst for normal fertilization in IVF it was the pre-freeze motility. These results may be explained by the compensatory effects of post-thaw processing of spermatozoa for IVF, but not for DI in our clinic.
Adolescent↗
Normal sperm-zona pellucida interaction and fertilization in vitro in alpha-1,3-galactosyltransferase gene knockout mice.
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Animals↗
Protein kinase C plays an important role in the human zona pellucida-induced acrosome reaction.
To investigate the involvement of protein kinases in signal transduction in the human zona pellucida (ZP)-induced acrosome reaction (AR), the effects of protein kinase (PK) activators, dibutyryl cAMP (PKA) and cGMP (PKG), phorbol 12-myristate 13-acetate (PMA, PKC), and the PKC inhibitor, staurosporine were studied. Sperm samples were obtained from normozoospermic men with normal sperm-ZP binding. Oocytes were obtained from other patients with failure of fertilization in vitro. Motile spermatozoa selected by a swim-up technique were pre-incubated with 2.5-20 microM PMA, 1 mM dibutyryl cAMP or cGMP, 3 mM pentoxifylline or 0.125-2.0 microM staurosporine for 30 min and then incubated with four oocytes for 2 h in human tubal fluid supplemented with bovine serum albumin. The spermatozoa bound to the ZP were dislodged by repeatedly aspirating the oocytes with a small bore pipette and the state of the AR was determined by fluorescein-labelled Pisum sativum agglutinin. Motility and movement characteristics were assessed by computer-assisted sperm analysis (CASA) after incubation of spermatozoa with PMA for 30 min and 2 h. The dibutyryl cAMP and cGMP analogues had a small positive effect (P < 0.05) but pentoxifylline had no effect on stimulating the ZP-induced AR (P > 0.05). In contrast, PMA stimulated ZP-induced AR in a marked dose-dependent manner. Only the highest concentrations (15-20 microM) of PMA significantly decreased percentage motility (P < 0.001). Doses of 2.5-15 microM of PMA significantly stimulated ZP-induced AR without decreasing motility (P < 0.001). The PKC inhibitor, staurosporine (0.125-0.25 microM) significantly inhibited ZP-induced AR without affecting motility (P < 0.001). Sperm samples from 33 normozoospermic men were used for studies of the ZP-induced AR augmented with 15 microM PMA. One sample did not show a response to PMA stimulation. Among the 14 men with low ZP-induced AR, half had normal responses to PMA and other half had low responses to PMA. In conclusion, activation or inhibition of PKC significantly increases or decreases human ZP-induced AR suggesting that PKC plays a important role in the signal transduction pathway for the physiological AR.
Acrosome↗
Male infertility of undetermined etiology.
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Adult↗
The effects of coculture with autologous cryopreserved endometrial cells on human in vitro fertilization and early embryo morphology: a randomized study.
PURPOSE: The aim of this study was to examine the influence of endometrial cells on the fertilization rate and early embryonic morphology following routine in vitro fertilization (IVF). Cryopreservation with subsequent thawing allowed the use of autologous somatic cells, thus minimizing the risk of transmission of infective agents. Interpatient variability was eliminated by randomizing oocytes from each cycle into the control or coculture group. RESULTS: Two hundred ninety-four oocytes from 24 IVF cycles (21 patients) were included in the study (145 coculture and 149 control). The normal fertilization rate of control oocytes (56.4%) was not significantly different from that of oocytes cocultured with endometrial cells (61.4%). The mean number of blastomeres in cocultured embryos (3.65) was not significantly different from the number in control embryos (3.46) 2 days after insemination, but the proportion of embryos with minimal or no fragmentation was significantly higher in the coculture group [34/84 (40.5%) vs. 17/80 (21.3%); P < 0.01]. CONCLUSIONS: The inclusion of cryopreserved autologous endometrial cells in routine clinical IVF procedures does not influence fertilization or the early cleavage rate but may reduce the extent of embryo fragmentation during the early cleavage divisions.
Adult↗
Protective effect of antioxidants on the impairment of sperm motility by activated polymorphonuclear leukocytes.
OBJECTIVE: To test the ability of antioxidants to reduce the loss of sperm motility caused by reactive oxygen species generated by polymorphonuclear leukocytes (PML). DESIGN: Standardized preparations of leukocyte-contaminated semen were created by suspending known concentrations of purified spermatozoa and PML in seminal plasma. After the stimulation of reactive oxygen species generation with phorbol ester, the spermatozoa were washed and incubated in culture medium before an analysis of their movement. The ability of antioxidants to counteract the free radical-induced loss of sperm motility observed under these circumstances was assessed. SETTING: An institutional research laboratory. PARTICIPANTS: The semen was obtained from normal volunteers. INTERVENTIONS: The following were tested: vitamins C and E, dimethylsulfoxide, catalase, hypotaurine, N-acetylcysteine, and reduced glutathione. MAIN OUTCOME MEASURES: Reactive oxygen species generation was monitored by luminol-dependent chemiluminescence. Sperm motility was assessed manually and by computer-aided semen analysis. RESULTS: Consistent impairment of sperm motility and average path velocity was observed in the presence of activated PML. This effect was reduced by the concomitant presence of glutathione, N-acetylcysteine, hypotaurine, and catalase. CONCLUSION: Antioxidants can protect against the damaging effect of leukocyte-derived reactive oxygen species on sperm movement and may be of clinical value in assisted conception procedures.
Antioxidants↗