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D Y Liu

Publications and source records attributed to D Y Liu.

At least 55 records · Page 3Linked to original sources
PubMed1997

Novel anti-inflammatory compounds induce shedding of L-selectin and block primary capture of neutrophils under flow conditions.

Leumedins are small molecules that inhibit neutrophil movement into inflamed tissues. These compounds have been shown to inhibit the adherence of neutrophils in static adhesion assays mediated by beta2-integrins. We now report that leumedins, like activating agents, induce the loss of L-selectin from the neutrophil surface. The loss of L-selectin is unrelated to the inhibition of static adhesion, since neutrophils that have been pretreated with leumedins to cause shedding of L-selectin, followed by removal of drug, adhere normally in a static adhesion assay, and this adhesion is inhibited upon readdition of leumedin. In an assay of adhesion to endothelial cells under conditions of physiologic wall shear stress, leumedins prevent both primary capture of neutrophils mediated by L-selectin and firm adherence mediated by beta2-integrins.

Anti-Inflammatory Agents↗
PubMed1997

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↗
PubMed1997

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↗
PubMed1997

Solid phase extraction and HPLC determination of 9-benzyladenine and isomeric 9-(nitrobenzyl)adenines and their metabolic N1-oxides present in microsomal incubates.

9-Benzyladenine, 9-(2-nitrobenzyl)adenine, 9-(3-nitrobenzyl)adenine and 9-(4-nitrobenzyl)adenine were metabolized to 9-benzyladenine-N1-oxide, 9-(2-nitrobenzyl)adenine-n1-oxide, 9-(3-nitrobenzyl)adenine-N1-oxide and 9-(4-nitrobenzyl)adenine-N1-oxide, respectively, by animal hepatic microsomes. For the quantitative determination of the substrates and metabolites present in microsomal incubates, an off-line solid phase extraction procedure, using columns paced with C18 silica bonded phase, was developed. The extraction recovery for these 9-alkyladenines and their N1-oxides was in the range of 92-101%. A reversed-phase HPLC method was established with an ODS column at a column temperature of 50 degrees C. The mobile phase consisted of H20-MeOH-diethylamine (65:35:0.5, v/v/v). pH 6.8. The above analytes were monitored at 233 nm and retention times of all analytes were within 6-14 min. The within-day coefficients of variation (CV) for the determinations were in an acceptable range. The biotransformation of BA and NBAs to N1-oxides by hamster microsomes was determined under the experimental conditions employed.

Adenine↗
PubMed1997

Human intestinal permeability of piroxicam, propranolol, phenylalanine, and PEG 400 determined by jejunal perfusion.

PURPOSE: To determine the human jejunal permeabilities of compounds utilizing different transport mechanisms using a regional perfusion approach and to establish a standard procedure for determining drug permeability class to be used for the establishment of drug product bioequivalence standards. METHODS: Six healthy male volunteers participated in this study. A multi-lumen perfusion tube was inserted orally and positioned in the proximal region of the jejunum. A solution containing piroxicam, phenylalanine, propranolol, PEG 400 and PEG 4000 was perfused through the intestinal segment at a rate of 3.0 ml/min. Perfusate samples were quantitatively collected every 10 minutes for two 100 minute periods with an intermediate wash out period to determine intra and intersubject variation. RESULTS: The mean P(eff) (+/-SD) of piroxicam, phenylalanine, propranolol, and PEG 400 were 10.40 +/- 5.93, 6.67 +/- 3.42, 3.59 +/- 1.60, 0.80 0.46 x 10(-4) cm/sec, respectively. The coefficient of variation for the intersubject variability, first and second perfusion periods were: piroxicam, 60.5% and 57.1%; phenylalanine, 52.8% and 57.8%; propranolol, 62.1% and 44.6%; and PEG 400, 81.7% and 42.3%, indicating a slightly lower CV for the second perfusion period in the same subject. The intrasubject CV's between the two perfusion periods were: 19.4%, 21.3%, 23.6% and 41.0% respectively, indicating a smaller intraindividual variation for all compounds studied. CONCLUSIONS: Piroxicam, a nonpolar drug exhibited the highest permeability of the compounds studied. The intrasubject CV was lower than the intersubject CV, indicating consistent permeability estimation within subjects. The methodology is useful for permeability estimation regardless of absorption mechanism and can be used to establish a consistent data base of human permeabilities for estimation of human drug absorption and for establishing the biopharmaceutic permeability class of drugs.

Adult↗
PubMed1997

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↗
PubMed1997

The role of CD11b/CD18 mediated neutrophil adhesion in complement deficient xenograft recipients.

Hyperacute rejection (HAR) of discordant xenografts is dependent on local complement activation. The formation of a functional complex of the complement components C5b-9 (membrane attack complex, MAC) causes endothelial injury and activation leading to coagulation and inflammation. In PVG rats which selectively lack the C6 component of complement, the MAC complex is not formed, whereas early split products of the complement cascade are produced normally. We reported previously that HAR is averted in C6 deficient xenograft recipients, and that subsequent accelerated acute rejection (AAR) can be delayed by inhibition of CD11b/CD18 (Mac-1) dependent neutrophil adhesion using leumedin, a member of a novel class of anti-inflammatory agents. Here we report the in vivo effects of a dose-response study using 2 new members of another class of Mac-1 directed agents designated nactins. Discordant cardiac xenografts from Hartley guinea pigs were heterotopically grafted into PVG(C6-) and PVG(C6+) rats. Experimental animals were divided into 3 groups receiving leumedin (group 1) or nactin (groups 2 and 3). Control animals received intravenous saline solution only. All C6(+) rats rejected their grafts hyperacutely within 10 to 15 min, irrespective of mode or dosage of treatment. C6 deficient controls rejected grafts within 17.7 +/- 3.5 h (n = 10). Treatment with leumedin/nactin prolonged graft survival up to 61.0 +/- 4.7 h (n = 4-6), with dose dependent differences in effectiveness among the 3 compounds tested. Histology showed that treatment was associated with less edema, hemorrhage, and neutrophil infiltrate at 2, 6, and 12 h. The marked decrease in hemorrhage seen in nactin-treated animals may reflect an interaction of Mac-1 with blood coagulation factors. Our data confirm that the neutrophil adhesion pathway is involved in AAR, especially when complement mediated injury due to MAC is restricted.

Acute Disease↗
PubMed1996

Relationship between the zona pellucida (ZP) and ionophore A23187-induced acrosome reaction and the ability of sperm to penetrate the ZP in men with normal sperm-ZP binding.

OBJECTIVE: To determine whether the proportions of sperm undergoing the acrosome reaction (AR) on the zona pellucida (ZP) or on exposure to the calcium ionophore A23187 correlate with sperm-ZP penetration in men with normal sperm-ZP binding. DESIGN: Sperm samples from 14 fertile, 50 normozoospermic, and 21 teratozoospermic men with normal sperm-ZP binding were used to study ZP and ionophore-induced AR and sperm-ZP penetration. SETTING: University research unit associated with a clinical infertility and IVF program. MAIN OUTCOME MEASURES: The proportion of sperm undergoing the AR induced by ZP and A23187, the number of sperm bound to and penetrating into the ZP, the proportion of ZP penetrated by sperm, and semen characteristics were analyzed. RESULTS: There were highly significant correlations between the percentage AR of sperm bound to the ZP and both the proportion of ZP penetrated and average number of sperm penetrating per ZP (Spearman r = 0.697 and 0.703). In contrast, A23187-induced AR did not correlate with either ZP-induced AR or sperm-ZP penetration. Although sperm concentration in semen correlated with both ZP-induced AR and sperm-ZP penetration by Spearman test, it was not significant in multivariate regression analyses. CONCLUSION: Ionophore A23187-induced AR does not correlate with either ZP-induced AR or sperm-ZP penetration. The ZP-induced AR is correlated highly with sperm-ZP penetration. Testing ZP-induced AR may be useful for assessing infertile men with normal sperm-ZP binding. In particular, it will identify failure of ZP penetration because of specific defects of the AR on the ZP.

Acrosome↗
PubMed1996

A simple method for assessment of the human acrosome reaction of spermatozoa bound to the zona pellucida: lack of relationship with ionophore A23187-induced acrosome reaction.

Acrosome reactions induced by the calcium ionophore A23187 and zona pellucida (ZP) were studied. Sperm samples were obtained from fertile men or men with normal semen analysis and normal sperm-ZP binding. Oocytes were obtained, with the consent of the patients, after the failure of fertilization in vitro. Motile spermatozoa selected by a swim-up technique were incubated with 10 microM A23187 for 1 h, four oocytes for 2 h or solubilized ZP (4 ZP/microliters) for 2 h. Spermatozoa bound to the ZP were dislodged and collected in a small volume of phosphate-buffered saline by aspirating the oocytes with a glass pipette with an inner diameter (120 microns) slightly smaller than the diameter of the oocyte. The acrosome status of the spermatozoa was determined using fluorescein-labelled Pisum sativum agglutinin. The proportion of spermatozoa undergoing the acrosome reaction on the ZP at 2 h varied over a wide range (5-99%), but the agreement between results for the same semen sample exposed to different groups of oocytes was good: the standard deviations of the differences being 9%. Pre-incubation of spermatozoa for 2 h did not increase the ZP-induced acrosome reaction. Re-incubation of ZP with the same sperm suspension for 2 h after removing ZP-bound spermatozoa from the first 2 h incubation produced a significantly lower ZP-induced acrosome reaction in the second incubation (22 +/- 16%) than in the first incubation (30 +/- 14%; P < 0.001, n = 20). There was no significant difference in the ZP-induced acrosome reaction with oocytes with ZP which had or had not been penetrated by spermatozoa during the in-vitro fertilization insemination. Pre-incubation of spermatozoa with solubilized ZP blocked sperm-ZP binding. However, the acrosome reaction induced by solubilized ZP (4 ZP/microliters) was significantly lower than the acrosome reaction induced by intact ZP (10 +/- 5 and 30 +/- 13% respectively, n = 11, P < 0.001), but there was a high correlation (Spearman r = 0.822, P < 0.01) between the results. On the other hand, although the average of the acrosome reaction was similar for A23187 (42%) and for ZP (43%), there was no significant correlation between the results for the two stimuli (n = 60). In conclusion, a useful method for assessing the ZP-induced acrosome reaction has been developed using oocytes which failed to fertilize in vitro. The lack of a relationship between the result of the chemical (A23187) and physiological (ZP) stimuli for the acrosome reaction in the same subjects questions the biological basis of using A23187 for tests of sperm function. Solubilized human ZP in a concentration that blocks sperm-ZP binding is a less efficient inducer of the acrosome reaction than is intact ZP. It is possible that the three-dimensional structure of the ZP is important for induction of the acrosome reaction or that spermatozoa which bind to the ZP are more likely to acrosome react. Assessment of the physiological acrosome reaction for diagnosis of sperm defects which interfere with the fertilization process should be concentrated on the spermatozoa which are capable of binding to the ZP.

Acrosome↗
PubMed1996

Novel anti-inflammatory compounds prevent CD11b/CD18, alpha M beta 2 (Mac-1)-dependent neutrophil adhesion without blocking activation-induced changes in Mac-1.

Leumedins are small organic molecules with anti-inflammatory properties in vivo. We report here that leumedins inhibit the CD11b/CD18 alpha M beta 2 (Mac-1)-dependent adherence of neutrophils to serum proteins. The activation of neutrophils leading to adherence via Mac-1 is associated with an increase in cell surface Mac-1 level, and with an increased affinity of Mac-1 for adhesion partners. Inhibition of neutrophil adherence by leumedins does not require blocking the recruitment of Mac-1 from intracellular granules to the cell surface. Furthermore, leumedins do not block the expression on Mac-1 of the epitope for an "activation-specific" antibody (CBRM1/5). Time course studies show that leumedins inhibit adherence by targeting an event which occurs concurrently with changes in Mac-1 level and induction of the CBRM1/5 epitope. Therefore, leumedins block an unknown process which is permissive for Mac-1-dependent adherence.

Amino Acid Sequence↗
PubMed1995

Normal fertilization and embryo development by intracytoplasmic sperm injection of round-headed acrosomeless sperm.

OBJECTIVE: To investigate the ability of round-headed acrosomeless sperm to bind to the human zona pellucida (ZP) and oolemma and to fertilize human oocytes by intracytoplasmic sperm injection. DESIGN: Oocytes that had failed to fertilize in IVF were used for sperm-ZP and spermoolemma binding tests. Sperm from a fertile donor was used as a control for oocyte variability. Intracytoplasmic sperm injection was used for assisted fertilization. SETTING: University- and hospital-based reproductive research laboratory and tertiary referral IVF program. PATIENTS: Case study of a couple in which the man has 100% round-headed acrosomeless sperm in the ejaculate. MAIN OUTCOME MEASURE: Fertilization and embryo development and the ability of sperm to bind to the ZP and oolemma. RESULTS: No ZP or oolemma binding was achieved, but normal fertilization and embryo development was obtained after intracytoplasmic injection of round-headed acrosomeless sperm. However, no pregnancy was achieved after the transfer of two cleaving embryos. CONCLUSIONS: Normal fertilization and embryo development from round-headed acrosomeless sperm is possible with intracytoplasmic sperm injection. However, it remains to be reported whether pregnancy can result from fertilization with this type of sperm defect.

Acrosome↗
PubMed1995

Sperm preparation for intracytoplasmic injection: methods and relationship to fertilization results.

Sperm preparation for intracytoplasmic sperm injection (ICSI) is described and the effect of high speed centrifugation during preparation on fertilization rate is evaluated. No significant differences were found in the 2-pronuclear or abnormal fertilization rates between sibling oocytes injected with sperm prepared by swim-up or mini-Percoll combined with high speed centrifugation. The high fertilization rate obtained with both methods indicates that high speed centrifugation is not necessary to prepare sperm for ICSI. Fertilization rates were also compared for sperm obtained from ejaculates, fresh and frozen epididymal aspirates, and testicular biopsies. High fertilization rates were obtained from all groups but they were significantly higher in those oocytes injected with epididymal sperm (78% per oocyte surviving injection). The high fertilization rate with epididymal sperm may reflect sperm quality or may result from the method of sperm preparation for injection. Fertilization after the injection of sperm from which the tail was dislodged during immobilization was compared with that obtained using intact sperm. A significantly lower rate of 2-pronuclear fertilization was found in those oocytes injected with sperm heads only (55%) compared with intact sperm (68%), although cleavage rates between the two groups were similar. The use of hypo-osmotic medium to select potentially live sperm from an immotile sample is also described and fertilization was obtained after the injection of sperm with a structural defect which were selected using this technique. These results indicate that high fertilization rates can be obtained with ejaculated, epididymal and testicular sperm without special treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Separation↗
PubMed1995

Ability of spermatozoa to bind to the zona pellucida during oligozoospermia induced with testosterone during a male contraceptive trial.

To determine the ability of spermatozoa to bind to the zona pellucida (ZP) in testosterone-induced oligozoospermia, previously fertile men participating in the World Heath Organization (WHO) male contraceptive trial in Melbourne were studied while oligozoospermic to various degrees. Semen analysis were performed according to WHO methods. One or two ejaculates from each subject were cryopreserved before commencing weekly intramuscular injections of 200 mg testosterone enanthate. The frozen spermatozoa were used as controls for ZP-binding tests of spermatozoa obtained during testosterone-induced oligozoospermia (< 10 x 10(6)/ml) in either the suppression or efficacy (n = 6) and recovery (n = 3) phases. Two other subjects in the recovery phase with normozoospermia were also tested. Human oocytes that failed to fertilized in vitro from infertile patients were used for the sperm-ZP binding test. Control (frozen) spermatozoa were labelled with fluorescein isothiocyanate and test (oligozoospermic semen) spermatozoa were labelled with tetramethylrhodamine B isothiocyanate. A mixture of equal numbers of labelled motile control and test spermatozoa were incubated with 4-6 ZP. There was a significantly (p < 0.01) lower number of spermatozoa bound per ZP in oligozoospermic samples (65 +/- 7, mean +/- SEM) than in controls (80 +/- 7). However, there were still large numbers of spermatozoa bound to the ZP for all the oligozoospermic samples. Five subjects had similar numbers of spermatozoa bound to the ZP for both control and oligozoospermic samples. Overall, the ZP-binding ratio of test and control spermatozoa averaged 0.82 (range 0.51-1.13).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Assessment of the Sperm Quality Analyzer.

OBJECTIVE: To assess the relationship between the results of the Sperm Quality Analyzer (United Medical Systems Inc., Santa Ana, CA), which measures motile sperm concentration by light scattering, conventional manual semen analysis characteristics, and computer-assisted sperm motility analyses. DESIGN: Sperm Quality Analyzer measurements and manual and computer-assisted semen analyses were performed on 150 (50, 62, and 38) samples in three laboratories and the results were compared. SETTING: The study was performed in the Andrology Laboratory of Prince Henry's Institute of Medical Research, Monash Medical Centre, and Andrology Laboratory and Reproductive Biology Unit at the Royal Women's Hospital, Melbourne, Victoria, Australia. PATIENTS: Patients presented to the laboratories for routine fertility evaluation in the male and were selected at random to reflect the range of normal and abnormal samples seen in the laboratories. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Sperm count, motility (percent motility, motility index, velocity, and amplitude of lateral head displacement [ALH]), morphology, and normal acrosomes were evaluated by manual and computer-assisted semen analysis and sperm quality analyzer motility index. RESULTS: Spearman nonparametric univariate analysis showed strong correlations between sperm motility index and manual sperm concentration, motility, abnormal morphology, and normal acrosomes by Pisum sativum agglutinin; and computer-assisted sperm motility analysis sperm concentration, motile concentration, and percent static. Curvilinear velocity, straight-line velocity (VSL), and linearity also were related significantly to sperm motility index values. By multiple regression analysis, the significant covariates of the sperm motility index were motile sperm concentration, abnormal morphology, ALH, and straight-line velocity and these accounted for 85.5% of the variance of the sperm motility index. CONCLUSIONS: The Sperm Quality Analyzer is easy to use. The good correlation between the sperm motility index, motile sperm concentration, and, in addition, a number of other semen parameters supports the use of the Sperm Quality Analyzer for screening patients and in situations that warrant a rapid verification of semen quality, such as in the IVF or artificial insemination clinic. Further investigation of the Sperm Quality Analyzer in the management of male infertility is warranted.

Acrosome↗
PubMed1995

Fertilization and pregnancy with acrosome intact sperm by intracytoplasmic sperm injection in patients with disordered zona pellucida-induced acrosome reaction.

OBJECTIVE: To determine whether fertilization and pregnancy could be obtained by injection of acrosome-intact sperm into the cytoplasm in patients with persistent failure of fertilization in IVF-ET associated with disordered zona pellucida (ZP)-induced acrosome reaction (AR). DESIGN: Sperm-ZP binding and penetration and ZP-induced AR were compared between patients and fertile donors. Acrosome-intact sperm removed from the ZP were injected into the cytoplasm of the oocytes. SETTING: Reproductive Biology Unit, Royal Women's Hospital. MAIN OUTCOME MEASURES: The proportion of ZP penetrated and ZP-induced AR and fertilization and pregnancy after intracytoplasmic sperm injection were analyzed. RESULTS: Most (7/8) of the patients had consistently normal sperm characteristics including concentration, motility and velocity, acrosomes, and morphology. Mean number of sperm bound to the ZP was not significantly different between patients (97 sperm/ZP) and fertile donor controls (100 sperm/ZP). However, AR of sperm bound to the ZP was significantly lower in the patients (4%) than in controls (61%). None of the ZP (n = 32) were penetrated by patient sperm whereas all (n = 32) ZP were penetrated by control sperm. Acrosome intact sperm removed from the ZP were used for intracytoplasmic sperm injection. All patients had > or = 50% normal fertilization and embryo development. Three pregnancies (one early aborted, two ongoing) were achieved after the transfer of fresh or frozen embryos. CONCLUSION: Acrosome-intact human sperm can produce a high fertilization rate and pregnancies after intracytoplasmic sperm injection in patients with disordered ZP-induced AR. The acrosome reaction is unlikely to be important for fertilization with intracytoplasmic sperm injection.

Acrosome↗
PubMed1994

A new test for the assessment of sperm-zona pellucida penetration: relationship with results of other sperm tests and fertilization in vitro.

The spermatozoa of some patients attending for in-vitro fertilization (IVF) fail to penetrate the zona pellucida in vitro. A test has been devised to identify these cases. It is based on the number of spermatozoa penetrating into the zona pellucida, which were counted after removing spermatozoa bound to the zona surface by vigorous aspiration of each oocyte through a narrow gauge (120 microns) glass pipette. The oocytes were collected from 197 patients undergoing IVF treatment with their own gametes; 79 with no oocytes fertilized and 118 with some oocytes fertilized. Sperm motility, morphology and DNA normality (acridine orange stain) were also measured. The relationships between sperm test results and IVF rate were examined by logistic regression. The proportions of penetrated zonae, normal sperm morphology and normal DNA were the most significant factors related to IVF rate in the whole group. Also, in patients with > or = 30 spermatozoa bound per zona pellucida or with normal sperm morphology > or = 30%, the proportion of penetrated zonae and normal DNA were most significant. Oocytes from 42 patients who had zero fertilization and low sperm-zona binding (average, 2.2 spermatozoa/zona pellucida) were re-incubated with normal donor spermatozoa: large numbers of spermatozoa bound (average, 88 spermatozoa/zona pellucida) and each zona was penetrated by at least one spermatozoon. In conclusion, the percentage of zonae penetrated was the variable most significantly correlated with IVF rate. Penetration of the zona was also strongly related to fertilization rates in patients without defects of sperm morphology and sperm-zona binding.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1994

Acrosome status and morphology of human spermatozoa bound to the zona pellucida and oolemma determined using oocytes that failed to fertilize in vitro.

It is known that only acrosome-reacted spermatozoa can fuse with the oolemma during normal fertilization with zona pellucida-intact oocytes. The aim of this study was to determine if the oolemma of human zona pellucida-free oocytes selectively binds spermatozoa with normal morphology and a reacted acrosome. Oocytes that failed to fertilize in vitro because of severe sperm defects were used. The zona pellucida was removed with acidic (pH 2-3) saline. Sperm samples were obtained from normal fertile donors and normozoospermic men. Motile spermatozoa were selected with a swim-up technique and 2 x 10(6)/ml incubated with oocytes. The results from 23 experiments showed that at 2 h there was a significantly higher mean percentage of acrosome-reacted spermatozoa bound to the zona pellucida (mean +/- SD, 42 +/- 22) than in the insemination medium (27 +/- 12). In contrast, all spermatozoa bound to the oolemma at 2 h were acrosome reacted. Furthermore, each fresh zona pellucida had > 100 spermatozoa bound compared with an average of 28 (range 4-81) spermatozoa bound per zona pellucida-free oocyte. There was no significant difference in the zona pellucida-induced acrosome reaction between fresh (45 +/- 21) and salt-stored (35 +/- 22) zonae pellucidae. The percentage with normal morphology was significantly higher for spermatozoa bound to the zona pellucida (84 +/- 13) and oolemma of zona pellucida-free oocytes (71 +/- 25) than for spermatozoa in insemination medium (39 +/- 11) (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Acrosome↗