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1.
During spermiogenesis, mammalian chromatin undergoes replacement of nuclear histones by protamines, resulting in a DNA that is highly condensed in the mature sperm. We have previously demonstrated that a percentage of human spermatozoa exhibit 1) positivity to the guanine-cylosine-specific chromomycin A3 (CMA3) fluorochrome and 2) the presence of endogenous nicks in their DNA. In situ protamination of mature human sperm limits the percentage of sperm positive to CMA3 and exhibiting endogenous nicks. In this study, we report further investigations that aim to clarify the relationship existing between levels of CMA3 stainability and the presence of endogenous nicks in the DNA of mature human spermatozoa. Human spermatozoa from 25 different samples showed values of sensitivity to the CMA3 fluorochrome ranging from 13% to 75%. The same samples showed a percentage of sensitivity to endogenous nick translation ranging from 1% to 38%. A strong correlation (r = 0.86) was evident between these two parameters. Prior staining of sperm with the CMA3 fluorochrome drastically reduced sensitivity to nick translation. In contrast, previously nick-translated sperm stained with CMA3 showed very little difference from samples that had not been pretreated. The presence of nicked sperm in the ejaculate may indicate anomalies during spermiogenesis and be an indicator of male infertility.  相似文献   

2.
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   

3.
During mammalian spermatogenesis, the chromatin of the spermatogenic cells is profoundly reorganized. Somatic histones are partly replaced by testis-specific histones. These histones are then replaced by transition proteins and finally by protamines. This series of nucleoprotein rearrangements results in a highly condensed sperm cell nucleus. In contrast to spermatozoa from other species, human spermatozoa still contain a significant amount of histones, including testis-specific histone 2B (TH2B). In the present study it is shown that an antibody targeting tyrosine hydroxylase, which has been found previously to cross-react with rat TH2B, also specifically immunoreacts with human TH2B on Western blots, in immunohistochemistry of human testis tissue, and in immunocytochemistry of decondensed human spermatozoa. In human testis tissue, TH2B immunostaining first apparent in spermatogonia, shows marked variation, especially at the pachytene spermatocyte stage, and then reaches an intense signal in round spermatids. Shortly before spermatid elongation, a portion of the spermatid nucleus, corresponding to the acrosomal region, loses its immunoreactivity. During condensation of the spermatid nucleus, the immunodetectability of TH2B disappears gradually, from the anterior region of the nucleus onwards. At the final stages of spermiogenesis, the immunostaining is completely absent. Immunocytochemical staining of spermatozoa revealed no TH2B immunosignal, but immunostaining was observed when spermatozoa obtained from semen were decondensed to make nuclear proteins accessible to the antibody. There was, however, a striking intercellular variability in the intensity of staining of spermatozoa within an ejaculate. In a population of 35 men attending our Andrology Clinic, we observed interindividual differences in total sperm TH2B content, which showed a significant, although not very pronounced, negative correlation with normal morphology (P = 0.05).  相似文献   

4.
Sperm cells from control donors of proven fertility and men from barren couples were studied by conventional procedures, i.e., light microscopy as well as flow cytometry. Light microscopy analysis of semen included the measurement of spermatozoa concentration, morphology, and motility. All the men from barren couples were asthenozoospermic at the conventional analysis of semen samples. Flow cytometry was applied to study two important parameters of sperm cells: mitochondrial membrane potential (MMP) assessed by the cationic dye JC-1 and DNA stainability with propidium iodide (PI). JC-1 staining was more reliable than the classical procedure used for this purpose, i.e., rhodamine 123 (Rh123) staining, and allowed us to show a positive correlation between MMP and spermatozoa motility. Regarding DNA analysis, a higher relative percentage of immature spermatozoa, showing a high accessibility of DNA to the intercalating PI fluorochrome, was found in men from barren couples compared to donors of proven fertility. The relative percentage of immature spermatozoa was significantly higher in semen from oligoasthenozoospermic subjects. Moreover, a positive correlation was found between immature spermatozoa, as evaluated by PI staining, and cells with depolarized mitochondria, as evaluated by JC-1 staining, suggesting that spermatozoa defective for nuclear maturity could be functionally defective cells. No correlation between immature spermatozoa determined by FCM and immature spermatozoa determined by light microscopy was found, suggesting that these two techniques assess sperm cell maturity at different levels.  相似文献   

5.
During the last years human exposure to environmental chemical contaminants (mutagenic/carcinogenic agents) has greatly increased. Evaluation of the biological effect of human exposure to mutagenic/carcinogenic agents in short-term tests is very important. In present paper the bacterial and eukaryotic tests for detection of genotoxic effect of environmental chemical contaminants have been described.  相似文献   

6.
A radiomicroassay for titration of spermocytotoxic antibody is described. The assay used [3H]AACTINOMYCIN D ([3H]Act D) to label damaged spermatozoa in a fashion analogous to penetration by vital dye. Optimal conditions for and some kinetics of the assay are presented. The assay is sensitive, reliable, simple to perform and uses only small amounts of serum and spermatozoa. Applied to sperm antibody positive human postvasectomy sera, the assay compared favourably in sensitivity eith vital dye microscopic observations and with parallel titration by the Isojima's immobilization tests.  相似文献   

7.
Percentage and types of morphological abnormalities found in canine spermatozoa were evaluated by three investigators using three stains (Giemsa-Wright stain [Diff-Quik], eosin Y/nigrosin [Hancock], and eosin B/nigrosin [Society for Theriogenology morphology stain] with conventional light microscopy, compared to phase contrast microscopy on unstained samples. The percentage of spermatozoa with abnormal heads, midpieces, and tails varied by technique and by investigator. Average percentages of morphologically normal spermatozoa were significantly higher in samples stained with Diff-Quik and samples examined by phase contrast microscopy than in samples stained with Hancock or Society for Theriogenology morphology stains. No effect of investigator on the percentage of morphologically normal spermatozoa was assessed. Results suggest that staining or preparation technique may alter the morphology of canine spermatozoa artifactually.  相似文献   

8.
The expression of integrin cell adhesion molecules (ITG-CAMs) by human ejaculated spermatozoa (fresh, capacitated and acrosome reacted) was evaluated by immunocytochemical, immunofluorescence and cell-ELIS methods, using monoclonal antibodies against alpha-6 and beta-3 subunits. Both the subunits were expressed on the acrosome region in fresh spermatozoa and post acrosomal region after acrosome reaction induced by calcium ionophore. The spermatozoa of the fertile men showed significantly (P < 0.001) higher expression of alpha-6 and beta-3 ITG subunits than the subfertile men. The percentage of spermatozoa reacting with alpha-6 and beta-3 mAbs increased significantly after the loss of acrosome when compared with fresh spermatozoa. Moreover, 35-40% of spermatozoa with normal shape and none of the spermatozoa with pathological shape showed a positive reaction. The quantitative analysis carried out by ELISA suggests that the levels of these ITG subunits decreased significantly (P < 0.001) in the subfertile subjects when compared with the fertile and the difference was more for alpha-6 than the beta-3. Hence our result suggests that alpha-6 subunit may be used as a clinical marker to evaluate the sperm quality in men.  相似文献   

9.
OBJECTIVE: To evaluate the penetration rates in the hamster zona-free oocyte sperm penetration assay (SPA) after exposure of spermatozoa to lysoplatelet-activating factor (LPAF) and lysophosphatidyl choline (LPC). DESIGN: Washed human spermatozoa were exposed to 100 microM of LPAF or LPC, followed by the assessment of their fertilizing ability using the SPA. The percentage of penetration, the sperm binding in the SPA, the percentage of motile spermatozoa, and the acrosome reaction rates were quantified. SETTING: Private research and university laboratories. PATIENTS, PARTICIPANTS: Fresh and frozen semen samples from fertile donors with proven fertility were used as well as fresh semen from infertile patients attending a fertility clinic. All the infertile patients had abnormal semen analysis. INTERVENTIONS: Human spermatozoa were incubated for 90 minutes in the presence or absence of LPAF or LPC at 100 microM with 0.3% albumin in Ham's F-10 (GIBCO, Dorval, Quebec, Canada), and their fertilizing ability was evaluated using the SPA. The effect of these lysophospholipids on the percentage of acrosome reaction was evaluated with a fluorescent microscopy technique. RESULTS: The penetration rates of the SPA in male factor increased significantly from 3% +/- 6% with controls to 19% +/- 9% and 34% +/- 22% after incubation with LPC and LPAF, respectively. Sperm-oocyte binding was not significantly increased in this group. Sperm penetration assay penetration rates were also increased in fertile cryopreserved spermatozoa with LPC and LPAF. In this group, the acrosome reaction was significantly increased from 2% +/- 1% in controls to 10% +/- 6% and 8% +/- 3% after incubation with LPC and LPAF, respectively. CONCLUSION: Lysoplatelet-activating factor and LPC independently increased the penetration rate of spermatozoa and the percentage of acrosome reaction. Lysophosphatidylcholine and LPAF may be beneficial in the treatment of spermatozoa with male factor infertility and may increase fertilization rates in IVF.  相似文献   

10.
To compare the importance of the route of insemination when using fresh or frozen semen, six groups of five bitches were inseminated either into the uterus (groups 4, 5 and 6) or the vagina (groups 1, 2 and 3) with fresh (groups 1 and 4) or frozen semen (groups 2, 3, 5 and 6). The fresh semen was collected when needed from the same dog. The frozen semen used in groups 2 and 5 was obtained from seven dogs on the same day, and pooled and processed simultaneously so that the groups were inseminated with exactly the same semen. The frozen semen used in groups 3 and 6 was obtained from different dogs and processed independently to evaluate not only the effect of the route of insemination but also the potential effect of the dog. The mean concentration of the fresh semen was 310 x 10(6) spermatozoa/ml, its motility was greater than 80 per cent and the percentage of normal live spermatozoa was 80 to 92 per cent. The mean spermatozoal concentration of the frozen semen was 200 x 10(6) spermatozoa/ml, its motility was greater than 60 per cent and the percentage of normal live spermatozoa was 80 per cent. In all the groups there were fewer than 15 per cent abnormal spermatozoa. The animals inseminated with fresh semen received significantly more spermatozoa than the others. The bitches were inseminated twice, three and five days after the estimated peak of luteinising hormone, with a total volume of 5 ml for the vaginal inseminations and 2 ml for the intrauterine inseminations. Sixty per cent of the bitches inseminated with frozen semen and 100 per cent of the bitches inseminated with fresh semen became pregnant, irrespective of the insemination technique used.  相似文献   

11.
The zona pellucida binding assay assesses the ability of spermatozoa to bind to the zona pellucida. The present study investigated the influence of: (i) prior oocyte exposure to spermatozoa on subsequent sperm-zona pellucida binding in vitro; and (ii) cryopreservation of oocytes. Only oocytes obtained from fertile donors were used and the binding capacity of non-inseminated, cryopreserved oocytes was compared with both inseminated/unfertilized, cryopreserved oocytes and inseminated/unfertilized, non-cryopreserved oocytes recovered from in-vitro fertilization cultures on sperm-zona pellucida binding using an intact zona model. There was no statistically significant difference in sperm-zona binding between non-inseminated, cryopreserved oocytes (range 9.6-23.2), inseminated/unfertilized, cryopreserved oocytes (range 15.0-16.0) and inseminated/ unfertilized, non-cryopreserved oocytes (range 3.3-23.0). The coefficient of variation for sperm binding to all oocyte groups was very large (range 37-121%). We conclude that neither prior exposure of human oocytes to human spermatozoa nor cryopreservation of human oocytes influences the subsequent binding of a different population of spermatozoa to the zona pellucida. However, large oocyte-to-oocyte variation of sperm-zona binding may diminish the usefulness of this assay in clinical practice and as a research tool.  相似文献   

12.
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   

13.
The colony-forming unit-granulocyte-macrophage (CFU-GM) assay, an essential test in evaluation of the quality of autologous grafts of hematopoietic stem cells, has yet to be standardized. With this aim in view, we carried out a multicenter study of five commercially available culture kits for CFU-GM evaluation. Four kits were methylcellulose-based (H4431, H4434, H4435, StemBio1d) and one was collagen-based (EasyClone-Multi). Using fresh and frozen samples of PBSC grafts, we compared CFU-GM and burst-forming unit-erythrocytes (BFU-E) growth using the EasyClone kit to each of the methylcellulose kits. BFU-E and CFU-GM clonogenicity of both fresh and frozen PBSC was clearly inferior with the H4431 kit, which provides conditioned medium only. CFU-GM numbers obtained with fresh and frozen PBSC samples were significantly higher with the EasyClone kit than with the H4434 and StemBio kits. BFU-E numbers were also higher with the EasyClone kit, but only when colonies were scored after May-Grünwald-Giemsa (MGG) staining. Finally, although the H4435 kit provides higher doses of recombinant cytokines than the EasyClone kit, CFU-GM and BFU-E numbers obtained for fresh or frozen PBSC with both kits were similar. In addition, CFU-GM and BFU-E numbers correlated well with CD34+ cell numbers for all five kits for both fresh and frozen PBSC. In summary, our study shows that the EasyClone-Multi and H4435 kits provide the best CFU-GM growth. The collagen-based EasyClone kit has the additional advantage of allowing gel staining and storage, which facilitates colony identification and, more importantly, makes gel exchange possible for standardization of the CFU-GM assay.  相似文献   

14.
Since the 1970s there have been conflicting reports of decreasing sperm counts in man and increasing testicular cancer. There is a hypothetical link between apparent adverse trends in several measures of human reproductive health and exposure to endocrine disrupters. Rodent bioassays are not suited for the large-scale screening of such chemicals because of their costs, complexity, and ethical concerns. Various in vitro assays have been used to examine the effects of these chemicals, but none has directly used semen as one of the target tissues in man. The present study has examined in the alkaline Comet assay in human sperm the effect of two estrogens--beta-estradiol and the phytoestrogen daidzein--and 1,2-epoxybutene, a metabolite of 1,3-butadiene, and compared them with the effects of the known reprotoxin, dibromochloropropane, in two fertile and two infertile frozen sperm samples and two fresh fertile samples. While differences were detected in the frozen fertile and infertile samples with flow cytometry, in the Comet assay both frozen and fresh samples exposed to the chemicals in vitro from fertile and infertile men produced similar altered responses by comparison with untreated samples. The integrity of DNA is necessary not only for the noncancerous state, but also for the accurate transmission of genetic material to the next generation. Thus this assay may be useful for examination of chemicals in fresh and frozen sperm samples.  相似文献   

15.
PURPOSE: Assays for the acrosome reaction are usually cumbersome and lack reproducibility. Accurate determination of acrosomal status is important in patients diagnosed with male infertility before proceeding with intrauterine insemination or in vitro fertilization. We determined the optimum capacitation time and acrosomal status of fresh semen specimens in normal fertile men with the Acrobead test, and whether the assay could be used to evaluate cryopreserved semen specimens. MATERIALS AND METHODS: Semen samples from 13 normal donors were divided, with half of the fresh ejaculate used for the Acrobead test and half cryopreserved for a minimum of 24 hours in liquid nitrogen before testing. Fresh and frozen specimens were prepared with the swim-up technique. Sperm concentration was adjusted to 4, 2, 1 and 0.5 x 10(6)/ml. in 4 wells of a 96-well tissue culture plate. Ten microl. polyacrylamide beads (1.5 x 10(6)/ml.) coated with anti-CD46 monoclonal antibodies (MH61 beads) were added to each well. The attachment of beads with acrosome reacted spermatozoa was scored after 0, 1, 3, 6 and 24 hours of incubation. Results were graded on a scale of 0 (no bead binding to the sperm) to 4 (complete attachment to the beads). Specimens with scores of at least 2 were considered normal. RESULTS: A score of at least 2 was noted in 3 of 13 fresh specimens (15.3%) at 1, 9 (69.2%) at 3, 11 (84.6%) at 6 and 13 (100%) after 24 hours. However, a significantly greater number of frozen specimens (8 of 13, or 62%) had a score of 2 or more at 1 hour of incubation and 100% bead attachment to sperm occurred at 3 hours. CONCLUSIONS: Our results indicate that in fresh semen specimens an incubation period of 6 to 24 hours can be used to screen individuals who present with normal sperm characteristics but have slow acrosome reactions. Early acrosome reaction observed in cryopreserved specimens indicates that these spermatozoa may have membrane damage and leakage of acrosome contents as a result of the freeze-thaw process. The Acrobead assay is a simple and objective test that can be used at a clinical andrology laboratory to evaluate the acrosomal status of fresh but not frozen human spermatozoa.  相似文献   

16.
PURPOSE: The aim of this study was to evaluate chromatin condensation of human spermatozoa following swim-up compared to glass-wool separation. Semen aliquots from men attending an andrological outpatient clinic were processed by means of a swim-up procedure and glass-wool filtration. Chromatin condensation was recorded using aniline blue staining and results were reported according to color intensity of stained sperm heads. Morphometric measurements of sperm heads were performed on stained sperm samples. RESULTS: Glass-wool filtration resulted (i) in a significantly higher total motile sperm count (P < 0.0005) compared to swim-up and (ii) in a significantly higher percentage of normal chromatin-condensed spermatozoa compared to the ejaculate (P < 0.01). CONCLUSION: In contrast, comparing swim-up to the ejaculate, the percentage of matured nuclei (unstained spermatozoa) retrieved following swim-up was significantly lower (P < 0.005). Glass-wool filtration separates human spermatozoa according to motility and size of the sperm head. The size of the sperm head closely correlated with the chromatin condensation quality.  相似文献   

17.
DNA content analysis of formalin fixed paraffin embedded (FFPE) tissue permits determination of the influence of DNA content on the prognosis in cohorts of patients for whom the clinical outcome is known. Of key importance in such an analysis is the accuracy of DNA content determination. Variations in the quality of DNA histograms from FFPE tissues of different types prompted a comparative evaluation of the preparative methodology of FFPE soft tissue sarcomas for DNA flow cytometry. Following deparaffination and rehydration of fixed tissue, and prior to fluorochrome staining, tissue blocks of 15 DNA aneuploid soft tissue sarcomas were subjected to repeated experimental (time x concentration) enzyme exposures. The goal of these studies was to define the optimal tissue specific retrieval technique with the coefficient of variation, maintenance of DNA aneuploidy, and DNA index as endpoints. After optimizing the technique, the DNA content of 50 soft tissue neoplasms derived from FFPE specimens was compared to the corresponding fresh surgical tissue. The observed 14 percent error rate in the determination of DNA ploidy status suggest limited utility for FFPE tissue in prospective therapeutic trials of soft tissue sarcoma.  相似文献   

18.
19.
Nuclear DNA content and cell cycle distribution in fresh tissues from 40 malignant and 10 benign breast tumors were assessed by flow cytometry using a DNA-specific fluorochrome, 4,6-diamidino-2phenyl-indole hydrochloride. DNA indices (DIs) (relative DNA content of tumor cells with reference to normal cells, 4,6-diamino-2phenyl-indole-hydrochloride ranged from 0.85 to 5.6 for malignant tumors and from 1.8 to 2.2 for benign tumors. Proliferating fraction (PF) (total cells in S and G2 + M phases) values were significantly higher in malignant tumors (35.4 +/- 14.75, mean +/- SD; P < .001) than in benign tumors (14.2 + 4.9) and adjacent normal tissues (6.6 + 2.73). DIs and cell cycle distribution correlated with clinicopathologic parameters, disease progression and survival. Four-year survival was greater in patients with a DI value of 1.8-2.2 as well as with SF values less than 10%.  相似文献   

20.
Endothelial cells (EC) produce cytokines, such as interleukin (IL)-1, IL-6, IL-8 and granulocyte-macrophage colony-stimulating factor (GM-CSF). These cytokines have an important role in the proliferation and differentiation of hematopoietic progenitor cells. On the other hand, anticancer agents generally cause hematopoietic disorders. However, little is known about the effects of chemotherapeutic agents on the secretion of cytokines from EC. Therefore, we investigated if treatment with platinum compounds may stimulate EC to secrete cytokines. EC newly isolated from a human umbilical vein were exposed to cisplatin, carboplatin, or TRK-710 for 80 min, then the cells were washed and placed in fresh medium. The levels of cytokines in the fresh medium were measured by the ELISA method, the levels of intracellular hydrogen peroxide (H2O2) were measured by flow cytometry, and the rhodamine 123-stained live mitochondria of the EC were observed under a confocal laser microscope. Platinum compounds induced cytokine production in human EC: cisplatin most prominently induced the release of IL-1 and IL-6, and TRK-710 had the greatest ability to induce the release of GM-CSF. Intracellular H2O2 production and IL-8 release were transiently induced immediately after treatment with platinum compounds, leading to IL-1 release when H2O2 production was eliminated. These results may provide new insights into the hematological toxicity induced by anticancer agents and the role of IL-1 and IL-6 secreted from EC in this toxicity.  相似文献   

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