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1.
To determine the clinical usefulness of Acridine Orange (AO) staining of spermatozoa as a screening test for the evaluation of semen quality during basic infertility investigation, semen smears from 103 randomly chosen males of subfertile couples were examined. The median duration of infertility was 4.5 years (range 1-15) and the median age was 33 years (range 21-43). The outcome of AO staining ranged from 5 to 81%, with a median of 24%, green fluorescent spermatozoa. Results were not significantly related to the parameters of semen analysis (sperm count, motility, standard morphology, viability, pH and volume, as well as fructose concentration and number of found cells) or to local sperm antibody testing and semen cultures. Fluorescence after AO staining was also not related to sperm functional capacity (evaluated using sperm-mucus interaction tests in vitro and in vivo), or the medical history of the patient. No significant differences in the AO test outcome were seen in patients with explained and unexplained infertility, or with regard to subsequent fertility [with a median value of 21% (range 5-46) green fluorescence in the fertile group, compared with a median value of 28% (range 9-81) green fluorescence in the other men]. The results of this prospective study indicate that under the usual conditions of conception, the AO test is not clinically useful as a screening procedure to determine semen quality during basic infertility investigation.  相似文献   

2.
This study was undertaken with the aim of investigating the cytogenetic constitution of normal as well as abnormal spermatozoa and immature germ cells found in semen of normal men and infertile patients. A specific protocol of double in-situ hybridization for chromosomes 1 and 17 based on colorimetric detection of the hybridization signals (ISH) and brightfield microscopy analysis of cellular morphology was applied. Also the influence of paternal age on sperm aneuploidy was investigated. We found that, at least in the age range analysed (28-54 years) and for semen of good quality (total normal motile counts above 10 x 10(6)) (n = 17), paternal age has no influence on baseline rates of sperm aneuploidy. However, with decreasing semen quality (total normal motile sperm counts below 5 x 10(6)) (n = 6) significantly higher rates of sperm aneuploidy for autosomes 1 and 17 were scored (0.8 versus 1.43%) (P < 0.001). Regardless of the type of semen analysed, a number of morphologically abnormal spermatozoa were found to be hyperhaploid or diploid in a high percentage of cases (20 and 10% respectively). The same was found for immature germ cells (aneuploidy rate of 18%). We conclude that in infertile men with poor quality semen a direct relationship may exist between the impairment of the spermatogenesis process (as reflected by an increased production of morphologically and cytogenetically abnormal germ cells) and rates of baseline aneuploidy occurring in normal spermatozoa. Infertile couples undergoing assisted reproduction treatment need to be counselled about the risk of using spermatozoa which may carry higher rates of non-disjunction for different chromosomes. While sperm hyper- or hypohaploidy for some chromosomes (X,Y) implies counselling couples about the risk of abnormal phenotype in their offspring, most autosomal sperm aneuploidies probably translate only into lower rates of embryo fertilization and survival.  相似文献   

3.
The techniques of Feulgen staining, acridine orange staining, and a sperm chromatin structure assay using acridine orange and flow cytometry were compared for selective examination of bovine sperm nuclei. Twenty frozen semen samples were simultaneously analysed by all three methods. The prevalence of abnormally condensed DNA and its relationship to other semen traits were determined in ejaculates from 70 bulbs presented for routine examination for breeding soundness and in frozen semen from 348 bulls evaluated over five years. A breeding trial with 118 beef heifers using semen from six bulls with different degrees of nuclear abnormalities was performed to assess the importance of the defects with respect to fertility. The results indicate that few spermatozoa with abnormal DNA condensation are found in normal semen, but the incidence increases with disturbance of spermatogenesis. However, high numbers of abnormally condensed nuclei were found in the absence of an increase in other defects. This nuclear defect might be at least partially of epididymal origin; it can lower fertility and can be compensated for by increasing the numbers of normal spermatozoa in the insemination dose. The percentage of abnormally condensed sperm nuclei as detected by Feulgen staining was significantly correlated with that detected by microscopy after acridine orange staining and by the sperm chromatin structure assay. We therefore consider the Feulgen technique to be a valuable tool for assessing the nuclear integrity of bovine spermatozoa.  相似文献   

4.
To determine predictive values of routine semen analysis, sperm morphology evaluation using strict criteria and DNA status for in-vitro fertilization (IVF), 66 consecutive couples undergoing IVF in a university hospital IVF programme were prospectively investigated. Semen samples from 66 men were evaluated by routine semen analysis, morphology evaluation using strict criteria and acridine orange staining for determination of DNA status. A new technique is described for acridine orange scoring which consisted of evaluation of two smears per case, with and without heat treatment. Resistance to heat-provoked denaturation was determined by the difference between two evaluations. A logistic regression model was built and receiver operating characteristic curves were constructed to determine the threshold values and to compare diagnostic properties. Morphology evaluation using strict criteria and concentration of progressively motile spermatozoa were found to be the principal parameters determining the sperm fertilizing capacity in vitro. The logistic regression model composed of morphology evaluation using strict criteria and acridine orange score had a powerful diagnostic capability for prediction of fertilization in vitro.  相似文献   

5.
BACKGROUND: Semen analysis is part of the routine assessment of infertile couples. WHO defines a sperm concentration above 20x10(6) per mL seminal fluid as normal. We studied the association between semen quality and the probability of conception in a single menstrual cycle in Danish couples with no previous reproductive experience. METHODS: In 1992-94, we invited 52,255 trades-union members aged 20-35 years, who lived with a partner and had no children to take part in the study; 430 couples agreed. The couples discontinued use of contraception, and were followed up for six menstrual cycles or until a pregnancy was verified within this period. Each man was asked to provide a semen sample at enrolment (which was analysed without freezing). Women kept a daily record of vaginal bleeding and sexual activity. The association between semen quality and likelihood of pregnancy was assessed by logistic regression, adjusted for sexual activity and female factors associated with low fertility. RESULTS: There were 256 (59.5%) pregnancies among the 430 couples: 165 (65.0%) among those with a sperm concentration of 40x10(6)/mL or more and 84 (51.2%) among those with lower sperm concentrations. The probability of conception increased with increasing sperm concentration up to 40x10(6)/mL, but any higher sperm density was not associated with additional likelihood of pregnancy. The proportion of sperm with normal morphology was strongly related to likelihood of pregnancy independently of sperm concentration. Semen volume and motility were of limited value in pregnancy prediction. INTERPRETATION: Our study suggests that the current WHO guidelines for normal semen quality should be used with caution. Some men with sperm counts above the lower limit of the normal range defined by WHO may in fact be subfertile.  相似文献   

6.
This study was designed to assess the effect of cancer treatments on the natural and assisted reproductive potential of men. A cohort of men with cancer, in whom radiotherapy and/or chemotherapy was planned, were invited to participate. Twenty-two pre- and post-treatment semen samples were analysed. The reproductive potential of participants was assessed with respect to the current range of fertility treatment options available. Abnormal sperm concentrations were found in 27% of patients pre-treatment compared to 68% post-treatment following a mean latency of 20 months from treatment. Fifty-nine percent of patients experienced a clinically significant decrease in sperm, concentration following radiotherapy and/or chemotherapy; 23% developed azoospermia following treatment. Eighty-two percent of patients with testicular malignancy had oligo- or azoospermia post-treatment. Only one patient had a clinically significant reduction in the percentage of motile spermatozoa post-treatment. Cryopreservation of semen prior to treatment improved the fertility prospects of 55% of patients. Intracytoplasmic sperm injection (ICSI) enhanced the fertility prospects of a further 14%. In the absence of, or after depletion of, cryopreserved semen, ICSI could enhance the fertility prospects of 45% of patients. Fertilization has been achieved by ICSI using spermatozoa retrieved by testicular biopsy from an azoospermic testicular cancer survivor 8 years after chemotherapy. It was concluded that chemotherapy and/or radiotherapy may depress semen concentration to the extent of rendering a man infertile. The severity of the reduction in sperm concentration following treatment is unpredictable but likely to be most severe in those with testicular malignancy and those treated with radiotherapy or alkylating chemotherapy agents. Not all men are keen to undergo an appraisal of their post-treatment fertility potential, for reasons which are unclear. Improving awareness and education of patients concerning the effects of both cancer and cancer treatments on reproductive potential is essential. With the advent of ICSI, it is possible to offer a very reasonable chance of conception in all men with cancer who present for cryopreservation of semen prior to treatment in whom spermatozoa (even in very low concentrations) are present in the ejaculate.  相似文献   

7.
To compare the efficiency of sperm preparation between the two-layer Percoll gradient and mini-Percoll methods, 50 normal and 33 abnormal semen samples from male partners of infertile couples were studied. The number of recovered spermatozoa, percentage of motility, percentage of normal morphology, and their survival at 24 and 48 hours were assessed. Both Percoll gradient techniques resulted in a significantly higher percentage of motility and percentage of normal morphology compared with the original semen samples (p < 0.0001). The two-layer Percoll gradient showed a higher sperm recovery than the mini-Percoll method (p < 0.001), but the latter resulted in a higher percentage of motility (p > 0.001) and a higher sperm survival rate at 24 hours (p < 0.05) than the former, regarding normal semen samples. These differences did not appear with abnormal semen samples when analyzed as a group. Considering each of the abnormal parameters separately, sperm recovery was significantly higher after the two-layer Percoll gradient in the case of astheno- and teratozoospermia (p < 0.05), but sperm survival at 48 hours was higher after the mini-Percoll gradient in the case of teratozoospermia (p < 0.05). It is concluded that both the two-layer Percoll gradient and mini-Percoll method can be used effectively for sperm preparation. The former yields a higher sperm recovery, but the latter should be considered regarding teratozoospermic samples and semen samples of very low volume.  相似文献   

8.
We have undertaken an analysis of semen from HIV infected men with regard to sperm counts and motility, non-spermatozoal cells, and viral nucleic acid. Regression analysis showed that sperm concentration and motility were positively associated with blood CD4 cell count. By contrast, non-spermatozoal cell concentration (round cells) was inversely related to CD4 count. Extracellular HIV RNA was detected in the majority of semen samples and proviral DNA in a minority. Percoll gradient washing of 12 semen samples yielded six samples containing adequate sperm concentration for analysis. This washing procedure reduced prewash extracellular RNA to below detectable limits in all cases; proviral DNA present in two of the six prewash samples was also reduced to below detectable limits after washing. We conclude that semen washing before artificial insemination may reduce the risk of HIV transmission from an infected man to an uninfected woman. However, further evidence from prospective analyses of such an approach is required.  相似文献   

9.
OBJECTIVE: Sperm recovery using a single-layer Percoll procedure is significantly better than using the swim-up technique for infertile men and patients with normal sperm characteristics; however, in normal men results have been contradictory. Some studies have shown further improvement in semen quality with multiple layers. Therefore, this study compared the effect of single-layer and two-layer Percoll procedures on sperm characteristics of normozoospermic men. METHODS: Semen specimens from 10 normal donors were processed by layering 1 mL of the liquefied ejaculate on a single layer of 80% Percoll or on a two-layer (47% and 90%) Percoll gradient. Computer-assisted semen analysis was done to examine total motile sperm, percentage of recovery of motile cells, percent motility, curvilinear velocity, linearity, and amplitude of lateral head displacement. Each specimen was evaluated by the hypo-osmotic swelling (HOS) test, bovine cervical mucus penetration test, viability (eosin-nigrosin stain), and sperm morphology (World Health Organization and Kruger's strict criteria). RESULTS: Specimens processed with the two-layer Percoll procedure had significantly better recovery of spermatozoa, and significantly better percentage motility, linearity, amplitude of lateral head displacement, percentage tail swelling, and percentage viability than those separated on single-layer Percoll. Results for sperm morphology using WHO and Kruger's criteria were similar between the two methods (P = 0.92 for both sets of criteria). CONCLUSIONS: In normozoospermic men, the two-layer Percoll separation procedure significantly improves semen characteristics compared with separation on a single layer.  相似文献   

10.
OBJECTIVE: To look for correlations between acridine orange (AO) staining and semen parameters before and after sperm separation procedures and to assess whether the AO test predicts fertilization or pregnancy outcomes after standard IVF and intracytoplasmic sperm injection. DESIGN: Prospective study that simultaneously assesses sperm morphology and nuclear protein maturity on a cell-by-cell basis before and after preparative procedures. SETTING: University teaching hospital. PATIENT(S): Men (n = 140) undergoing diagnostic semen analysis. MAIN OUTCOME MEASURE(S): Acridine orange fluorescence of sperm nuclei, semen parameters, IVF outcome. RESULT(S): In unprocessed samples, 90% of sperm with normal heads displayed green fluorescence (mature nuclear protein); significantly lower percentages of green fluorescence were observed in sperm with abnormal heads. The percentage of mature normal sperm in the specimen correlated with motility. Sperm maturity after swim-up or Percoll gradient was significantly improved for sperm with normal or abnormal heads. The percentage of mature normal sperm correlated with motility after either Percoll or swim-up. Neither the percentages of mature nuclei nor mature normal nuclei correlated with fertilization or pregnancy outcome. CONCLUSION(S): Nuclear protein maturation correlates with sperm motility and morphology. Because morphologically normal and motile sperm are more mature, separation procedures should generate a population of sperm with the highest fertilization capacity. Acridine orange staining, however, did not predict fertilization efficiency or pregnancy outcome in IVF cycles.  相似文献   

11.
Tyrode fluid and Tyrode fluid plus Pentoxifylline were individually added to aliquots of semen samples obtained from 6 normal men and 6 infertile patients considered to have idiopathic normogonadotropic oligoasthenozoospermia. Pentoxifylline was added to final concentrations of 0.15, 0.30 and 0.60 mM. One aliquot with no addition served as control. Samples were incubated in 37 degrees C and observed by light microscopy at 30 minutes and at 1, 2 and 4 hours after obtaining the material. At observation time, semen quality was evaluated by determining the percentages of forwardly progressive spermatozoa, slowly progressive spermatozoa, "in situ" motile spermatozoa, live and non-motile spermatozoa and dead spermatozoa. Results reported included only the first and last category. Tyrode fluid did not affect significantly the motility and the duration of activity of spermatozoa. Ejaculated human spermatozoa both from normal and asthenozoospermic men added the Pentoxifylline at 0.30 and 0.60 mM showed a longer lasting activity than those of control semen and semen added only with Tyrode fluid.  相似文献   

12.
Sperm morphology of three healthy boars and three boars with spontaneous abdominal cryptorchidism in the right testis has been evaluated by light microscopy. For each boar, two ejaculates have been analysed, corresponding to semen collections at the ages of 6.5 months (first collection) and 8 months (seventh collection). A comparative study of the sperm malformations present in the seventh semen collection between the healthy boars and the unilateral abdominal cryptorchid boars has also been performed by light microscopy. Sperm malformations of the seventh semen collection from the unilateral abdominal cryptorchid boars have been examined by scanning and transmission electron microscopy. The frequency of mature spermatozoa, immature spermatozoa, aberrant spermatozoa and detached heads maintained normals values in the first and the seventh semen collection from the unilateral abdominal cryptorchid boars. The comparative study of sperm abnormalities in the seventh semen collection between the cryptorchid boars and the healthy boars indicated that the unilateral abdominal cryptorchid boars had a significantly higher frequency of primary abnormalities, and a significantly lower frequency of secondary abnormalities. Some primary abnormalities, such as crater defect, knobbed acrosome defect, nuclear crests and abaxial tails were only observed in the unilateral abdominal cryptorchid boars. It was concluded that unilateral abdominal cryptorchidism provokes disturbances in the late stages of spermiogenesis, at testicular level. Alterations in the sperm maturation process at epididymal level were not found.  相似文献   

13.
The effects on fertilization of the morphology of spermatozoa, acrosome reaction, reactive oxygen species (ROS) production, leukocyte contamination and the light scattering in flow cytometry of semen preparation were investigated in 73 couples undergoing their first in-vitro fertilization treatment. All men had normal concentrations of spermatozoa with sufficient motility (> or = 50%) and yield (> or = 6 x 10(6)) in the semen preparation on the day of oocyte retrieval. The light scattering properties of all cells present in the semen preparation, as assessed with flow cytometry, were correlated with fertilization. The proportion of metaphase I oocytes was also correlated with the fertilization rate of all collected oocytes and of metaphase II oocytes. ROS production, leukocyte contamination, spontaneous or calcium ionophore-stimulated acrosome reaction, percentage of normal morphology, and multiple anomalies index had no independent contribution.  相似文献   

14.
A cross-sectional study was conducted to determine the semen parameters (i.e. volume, concentration, motility, viability and normal morphology) of proven fertile males in Singapore and compare it with the World Health Organization (WHO) recommended normal values and to examine some factors that may affect spermatogenesis. A total of 243 men, whose wives were pregnant at the time of collection of semen, provided a semen sample each after sexual abstinence for 3 days. A questionnaire was used to elicit occupational exposure, alcoholic consumption, smoking history and past significant medical history. Most subjects had normal sperm volume (56.4%), concentration (79.8%), motility (69.5%) and viability (53.5%) based on WHO criteria. However, fertile men had a low mean percentage of normal sperm morphology (20.0%), although they were normally distributed. Cigarette smoking was associated with significantly lower semen volumes even after adjusting for alcohol consumption. The sperm parameters (i.e. volume, density, motility, viability and normal morphology) were not significantly associated with ethnic differences. The WHO criterion for normal sperm morphology is too stringent, and should be adopted with caution. Normal sperm morphology is but one of many parameters for assessment of fertility. Social alcohol consumption, cigarette smoking, and 'recent fever' did not appear to affect sperm quality in this group of fertile men.  相似文献   

15.
Research from 1930 to 1992 is reviewed with regard to storage of semen at reduced (0-5 degrees C or 10-15 degrees C) and at ambient temperatures. Diluents investigated have included synthetic buffers combined with sugars and egg yolk or its fractions, milk from various sources, glycine, and other substances. Irrespective of the diluent, dilution rate, temperature or conditions of storage, the spermatozoa deteriorate with time of storage. Changes include reduction in motility and morphological integrity of spermatozoa, accompanied by a decline in their survival in the female reproductive tract, reduction in fertility and increased embryonic loss. In critical studies, fertility declined rapidly when semen stored for more than 24 h was used for cervical insemination, but after intrauterine insemination some spermatozoa maintained their fertilizing capacity up to 10 days. Laparoscopic intrauterine or transcervical inseminations could be the means of improvement of fertility. These methods may eliminate the problem of sperm transport through the cervix and ageing of spermatozoa in the reproductive tract, thereby improving fertilization of ova and reducing embryonic loss.  相似文献   

16.
To clarify the role of urokinase plasminogen activator (uPA) in the mechanisms of regulating sperm motility and the ability of fertilizing, we investigated the quantities and activities of uPA in human seminal plasma and on the membrane of spermatozoa. Semens were harvested from 22 infertile patients with asthenospermia and 20 healthy fertile men according to WHO standards. To quantify the membrane-bound uPA in the samples, polyclonal antibodies against human urokinase were employed by means of a sandwich ELISA. The uPA activities in seminal plasma and on the surface of spermatozoa were determined using A-garose-Fibrine-Plate method and the experiment of immunological identification with polyclonal antibodies against urokinase. In lysates of spermatozoa, significantly lower levels of uPA (23.1 +/- 7.35 mu/10(6) cells) and uPA activity (5.13 +/- 3.85 mu/10(6) cells) were found in patient group as compared to healthy fertile men exhibiting normospermia (29.89 +/- 9.40 mu/10(6) cells and 10.17 +/- 6.18 mu/10(6) cells). In seminal plasma, uPA activity in patient group (2134 +/- 1581.3 IU/L) was also found significantly lower than that of normal group (3365 +/- 1859.5 IU/L). Positive correlations were observed between sperm motility and uPA quantities (r = 0.48, P < 0.005), as well as with uPA activities (r = 0.45, P < 0.005). Thus, it is inferred that membrane associated uPA on human spermatozoa may be related directly to sperm motility and fertility.  相似文献   

17.
Cytochemical defects in chromatin were examined by transmission electron microscopy (TEM) after the staining by alcoholic phosphotungstic acid (PTA) of normal and malformed ejaculated spermatozoa from 35 male partners of infertile couples, and in six sperm samples retrieved from the caput epididymidis of men affected by obstructive azoospermia. PTA staining was also analysed in normal ejaculates of fertile men after incubation of the washed spermatozoa with dithiothreitol (DTT) to reduce disulfides to thiols, or with DTT followed by iodoacetamide, a blocking agent for thiol groups. PTA stained 63 (27-100)% of malformed heads and 25 (10-100)% of normal sperm heads (median (range) n = 35; P = 0.0001, Wilcoxon matched pairs test). The percentage of normal heads stained by PTA was negatively correlated with the percentage of heads of normal form, with condensed chromatin and a normal acrosome (Spearman r = 0.75; P = 0.0001), and positively correlated with the percentage of malformed heads after conventional TEM analysis (Spearman r 0.60; P = 0.0001). Staining with PTA in normal heads was not correlated with the presence of non-condensed chromatin in otherwise normal sperm heads evaluated by conventional TEM analysis. In spermatozoa recovered from the caput epididymidis, 15% of normal heads were stained with PTA, significantly fewer than in ejaculated sperm samples (P = 0.014). The reduction of disulfides to thiols was associated with PTA staining of all normal heads, and this was prevented by incubation with iodoacetamide. We conclude that PTA staining of the nuclei of human ejaculated spermatozoa may indicate a defect of chromatin condensation, owing to an excess of free thiol groups. The lower percentage of normal epididymal sperm heads that stained with PTA in cases of obstructive azoospermia compared with ejaculated sperm may be related to an overoxidation of thils owing to the ageing of spermatozoa.  相似文献   

18.
Human spermatozoa are capable of a carrier-mediated gamma-aminobutyric acid (GABA) uptake. The uptake is dependent on the concentration of Cl- and Na+ in the external medium, and the kinetics of the carrier resembles high-affinity GABA transport proteins. The time-dependent uptake of GABA displays large interindividual differences and is not correlated to motility parameters or morphology in the individual sample. Incubation of human spermatozoa with radiolabeled GABA was performed. Swim-up preparations of human spermatozoa were incubated with [3H]GABA, and subsequent GABA uptake was measured at various times by scintillation counting. GABA was accumulated intracellularly, and the uptake could be inhibited by preincubation of the samples in 200 microM nipecotic acid. Addition of aminooxyacetic acid in the medium did not alter the results, indicating that the internalized GABA remained unmetabolized intracellularly throughout the observation period. Kinetic analysis of GABA uptake was performed, and the Km for GABA transport was 14 microM. GABA uptake was reduced by equimolar substitution of NaCl in the capacitating medium by KCl, choline chloride, LiCl, N-methyl-D-glucamine (HCl) or D-glucuronic acid (sodium salt). Maximal reduction of [3H]GABA uptake was observed when the Na+ fraction of the medium was replaced with KCl. The results indicate the presence of a high-affinity GABA transport protein in the plasma membrane of human spermatozoa. GABA uptake was subsequently measured in 30 individual semen samples from men of barren couples. Large interindividual differences in GABA uptake was observed, but GABA uptake was not correlated to motility parameters or to morphology in the individual samples analyzed.  相似文献   

19.
Semen samples were obtained from 153 patients attending the Centre de recherche en Reproduction Humaine et en Démographie (CRRHD, Bénin) and seminal neutral alpha glucosidase activity was evaluated. Semen contains testicular and accessory gland secretions. Oligozoospernia asthenozoospernia and leucospermia are involved in reducing the fertilizing ability of the spermatozoa. The present work was undertaken to evaluate the variations of seminal alpha glucosidase activity as a specific epididymal enzyme marker in these diseases. A significant positive correlation was demonstrated (P < 0.01) between alpha glucosidase activity and (1) number of spermatozoa in oligozoospermic and normozoospermic men (2) motility of spermatozoa in asthenozoospermic men. No correlation occurred between alpha glucosidase activity and leucospermia. The results of the present study suggest that alpha glucosidase specific activity of the semen was involved in the maturation and acquisition of motility by the germ cells. Otherwise, in our sample, epididymis is scarcely involved in various inflammatory diseases of the reproductive tract.  相似文献   

20.
In chronic spinal cord injury, semen obtained by assisted ejaculation is usually abnormal. We have assessed electroejaculation early after injury in seven patients. There were no adverse effects. Initial samples contained few or no spermatozoa but as patients emerged from spinal shock, semen improved and five had specimens cryopreserved. Thereafter sperm motility and viability decreased towards the pattern of chronic spinal cord injury by day 16. Cryopreservation was not possible in one patient with many medical complications and another who started electroejaculation 15 days after injury. Semen storage within the first 2 weeks after spinal cord injury is recommended for future fertility treatment.  相似文献   

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