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At least 19 recordsLinked to original sources
PubMed2004

Expectations for oocyte fertilization and embryo cleavage after whole sperm versus sperm head intracytoplasmic sperm injection.

OBJECTIVE: To compare oocyte fertilization and embryo development after intracytoplasmic sperm injection (ICSI) with a whole sperm vs. a sperm head. DESIGN: Retrospective study. SETTING: Hospital-based IVF practice. PATIENT(S): Fifty-three women undergoing 54 IVF-embryo transfer plus ICSI procedures between January 1999 and June 2002. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Oocyte fertilization, zygote cleavage, and embryo stage after 72 hours of culture. RESULT(S): A significantly higher fertilization rate was observed using whole sperm (72.2%) than when using sperm heads (56.4%). Zygote cleavage rates for whole sperm vs. sperm head ICSI were 96.4% and 92.7%, respectively. Embryo cell stage after 72 hours of culture for whole sperm vs. sperm head ICSI was 6.5 +/- 2.1 cells and 5.6 +/- 1.8 cells, respectively. Embryo grade at this same time point was not different (2.3 +/- 1.0 and 2.5 +/- 0.9, respectively). CONCLUSION(S): The ICSI using whole sperm produces superior fertilization rates compared to ICSI using sperm heads, but once oocytes were fertilized, zygote cleavage rates were not different between the two sperm sources. Oocytes injected with a whole sperm produced embryos of higher cell stage but equivalent quality compared to oocytes injected with sperm heads. Therefore, having only sperm heads for use in ICSI should not be a deterrent to using this procedure.

Adult↗
PubMed1995

Analysis of sperm quality in recombinant inbred mouse strains: correlation of sperm head shape with sperm abnormalities and with the incidence of supplementary spermatozoa in the perivitelline space.

Recombinant inbred strains were developed from reciprocal crosses between two inbred strains of mice (CBA and KE) differing in sperm head shape, proportion of normal sperm heads (CBA, 95%; KE, 78%) and fertilization efficiency (CBA, 100% of fertilized ova; KE, 72%), to determine whether the indices of sperm morphology and function were correlated. The following parameters were analysed in recombinant inbred and progenitor strains: index of sperm head shape (head width in the middle of its length/head length), percentage of abnormal sperm heads, percentage of spermatozoa with progressive movements, efficiency of penetration of hyaluronic acid polymer (Sperm Select) and percentage of fertilized ova after mating males from the tested strains with females from an outbred stock. For each investigated character, recombinant inbred strains, recombinant inbred EXCB and CBXE, could be divided into at least three categories: KE-like, CBA-like and intermediate, suggesting that in each case a minimum of two genes was involved. Recombinant strains derived from the reciprocal crosses of progenitor strains differed only with respect to the proportion of abnormal sperm heads, showing the involvement of the Y chromosome in determining this character. Penetration into Sperm Select was significantly correlated both with fertilization efficiency and sperm motility, while correlation with the proportion of normal spermatozoa did not reach the level of significance. However, there was a significant negative correlation of both sperm abnormalities and the incidence of supplementary spermatozoa in the perivitelline space with the index of sperm head shape.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2005

High rate of premature chromosome condensation in human oocytes following microinjection with round-headed sperm: case report.

A young couple proceeded to three ICSI treatment cycles because of male infertility. The semen samples varied between 10 x 10(6) and 36 x 10(6)/ml, 38 and 51% progressive motility but 0% normal morphology. Different types of sperm heads, mostly round-headed with varying spherical appearance (86%) were presented beside acephalic sperm (pinheads; 12%), both one- or two-tailed and the former also without a tail. Very few sperm (2%) exhibited slightly oval-shaped heads. Electron microscopy revealed the absence of the acrosome combined with disturbance of the chromatin condensation among the round-headed sperm. In all three cycles, the fertilization rate using the round-headed sperm fraction was very low with the best result of 2/18 (11%) two-pronucleate oocytes and one one-pronucleate oocyte obtained in the second ICSI cycle. The three oocytes cleaved and were transferred in the 3-4-cell stage without achieving a pregnancy. Of the 29 unfertilized and prepared oocytes from the last two cycles, 27 were informative and revealed the maternal metaphase II chromosomes in the haploid range and a high rate (85%) of premature chromosome condensation (PCC) of the sperm nucleus with remarkable variation in the degree of condensation. Thus, it appears that nearly all round-headed sperm from this patient were incapable of oocyte activation after ICSI, which could be due to non-release (or absence) of an activating factor. As a consequence, PCC was induced in the sperm nuclei by the chromosome condensing factors which were still active in the oopasm of the arrested oocytes.

Chromosomes, Human↗
PubMed2000

Identification of RS as a flagellar and head sperm protein.

RS is 20-kDa microtubule-associated protein found in several human tissues. Sequence analysis showed that the polypeptide is highly related to a rat protein whose level has been previously reported to be correlated with sperm fertility. The present study examines the intracellular distribution of RS in spermatozoa from both humans and rats employing a specific antibody to the polypeptide and immunofluorescence microscopy. We demonstrate that in humans, RS is mainly a flagellum protein, but in rats, it is also abundant in the sperm head. In the sperm tail, RS was found to be co-localized with beta-tubulin, a major component of the axoneme, suggesting that RS is also associated with the flagellum axoneme. Contrary to a previous report, incubation of isolated spermatozoa from both humans and rats in the presence of ornidazole, a reported male contraceptive drug in rats, did not result in modulation in the level of RS, suggesting that the drug does not act directly on sperm RS. Mol. Reprod. Dev. 55:189-196, 2000.

Amino Acid Sequence↗
PubMed2002

Morphometric characterization and classification of alpaca sperm heads using the sperm-class analyzer computer-assisted system.

Sperm morphology has been identified as one characteristic which can be useful in the prediction of sperm fertility, therefore, we hope that this study aimed at establishing standardized morphological criteria might serve in future studies dealing with the search for sperm parameters which facilitate an estimation of sperm quality. For this purpose, ejaculates from fertile alpacas were used to evaluate sperm head morphometry by means of the Sperm-Class Analyzer (SCA) computer-aided image analysis system. We defined three morphological categories according to sperm head size (normal 50%, small 26%, large 24%) and five categories according to sperm head shape (normal 47%, pyriform 3%, short 20%, round 1%, long 29%). Sperm classification according to shape was performed by first morphometrically characterizing sperm heads clearly falling into each of the shape categories. Thereafter, discriminant analysis was performed on the data from these typical sperm heads and the resulting classification functions were used to categorize 2,200 spermatozoa from 11 alpacas. Classification of sperm heads by this method agreed in 88% of the cases with most of the misclassifications being due to pyriform heads classified as long heads. Morphometric values obtained from samples of 50, 100, 150, 175 and 200 sperm heads were compared. At least 150 sperm heads should be evaluated to overcome sample size influence on sperm measurements. Significant differences in sperm morphometry were found between individuals (CV for morphometric parameters ranging from 1.3 to 13.0) and there were marked differences in the sperm morphological composition of the ejaculates. Within-animal CV ranged from 4.7 to 17.8 thus showing the high degree of sperm polymorphism present in the alpaca ejaculate.

Animals↗
PubMed1993

Morphometric analysis of intact sperm heads and of sperm nuclei in the mouse.

A morphometric analysis of mouse sperm and of their nuclei was undertaken to investigate their respective post-testicular maturation. Sperm were collected from the testis, caput and cauda epididymidis, and their corresponding nuclei were isolated. Results indicate that the post-testicular maturation of sperm is distinct from that of nuclei. The size of intact sperm heads increases in the caput followed by a subsequent decrease in the cauda. In contrast, sperm nuclei decrease progressively in size. In general, a greater magnitude and number of alterations in intact heads and nuclei occur while in transit from the testis to the caput than during passage to the cauda epididymis. These results suggest that the period immediately following their release from the testis is crucial to the complete morphological maturation of sperm heads and nuclei.

Animals↗
PubMed1986

Cryopreservation of human spermatozoa: correlations of ultrastructural sperm head configuration with sperm motility and ability to penetrate zona-free hamster ova.

Freezing and storage of human male gametes is associated with a reduction in the overall semen quality and establishment of pregnancy. This study was done to evaluate the integrity of sperm head ultrastructure (SHU) with computerized and vapor freezing. Comparisons were made between the effect of cryopreservatives glycerol (G) and dimethylsulfoxide (DMSO) on SHU. Twelve ejaculates from five proven fertile donors were studied with the use of routine semen analysis, zona-free hamster ova, and SHU. Both cooling processes, regardless of the preservative used, significantly reduced sperm function and the number of SH with intact plasma membranes. The staged cooling technique was substantially superior to vapor freezing in all parameters analyzed (P less than 0.01). G was less detrimental to the postthaw SHU than 1 M DMSO. A significant positive correlation (r = 0.98; P less than 0.01) was noted between the total number of intact SH and motile sperm. Computerized freezing in a G-diluted semen rendered a sperm environment that allowed the highest number of forms with intact SH membranes and with the best chances to penetrate zona-free hamster ova.

Animals↗
PubMed2006

Shaping the sperm head: an ER enzyme leaves its mark.

Lipid storage diseases are debilitating inherited metabolic disorders that stem from the absence of specific lysosomal enzymes that degrade selected lipids. Most characteristically, these disorders affect the nervous and the reticulo-endothelial systems, with massive organomegaly resulting from the presence of engorged, lipid-laden macrophages. In this issue of the JCI, Yildiz et al. describe the role of the ER-resident enzyme beta-glucosidase 2 (GBA2) in mice (see the related article beginning on page 2985). Surprisingly, GBA2 deficiency leaves bile acid and cholesterol metabolism intact, instead causing lipid accumulation in the ER of testicular Sertoli cells, round-headed sperm (globozoospermia), and impaired male fertility.

Animals↗
PubMed2003

Viable piglets generated from porcine oocytes matured in vitro and fertilized by intracytoplasmic sperm head injection.

Intracytoplasmic sperm injection (ICSI) of a nonmotile cell into the ooplasm for assisted fertilization is a highly specialized procedure for producing the next generation. The production of piglets by ICSI has succeeded when in vivo-matured oocytes have been used as recipients. Our objective was to generate viable piglets by using porcine oocytes matured in vitro and fertilized by ICSI after evaluating the efficacy of using donor spermatozoa in which the acrosome had been artificially removed by treatment with calcium ionophore A23187 (Ca-I). The rate of acrosomal loss in spermatozoa was increased significantly as the duration of treatment with 10 micro M Ca-I was prolonged for 30-120 min (Ca-I treated; 55.6-78.6%), whereas the rate was not different as the duration of incubation without Ca-I was prolonged for 30-120 min (control; 45.3-58.4%). On the sixth day of in vitro culture after injection of the sperm head and subsequent stimulation with an electrical pulse, the rates of blastocyst formation were not significantly different between the two groups: the rates for oocytes injected with Ca-I-treated sperm heads (incubated for 120 min) and for those injected with control sperm heads were 8.6% and 4.0%, respectively. The mean cell numbers of the blastocysts were not significantly different between the two groups (25.6 and 22.7, respectively). Within 2 h after the stimulation, the injected oocytes were transferred to estrous-synchronized recipients. The three recipients that received oocytes injected with Ca-I-treated sperm heads (77-150 oocytes per recipient) were not pregnant, whereas two of the four recipients given oocytes injected with control sperm heads (55-100 oocytes per recipient) were pregnant. One of these farrowed three (a male and two female) healthy piglets. The results demonstrate clearly that in vitro-matured oocytes injected with sperm heads are developmentally competent and can produce viable piglets. They also suggest that removal of the acrosome from the spermatozoon before injection does not affect the development of the blastocyst in vitro. This might not also improve the production of piglets in vivo.

Acrosome↗
PubMed1997

Failure of oocyte activation after intracytoplasmic sperm injection using round-headed sperm.

OBJECTIVE: To examine the outcome of intracytoplasmic sperm injection (ICSI) with round-headed sperm (globozoospermia). DESIGN: Retrospective analysis. SETTING: In vitro fertilization laboratory with extensive ICSI experience. PATIENT(S): A patient couple with infertility because of globozoospermia seeking ICSI treatment. MAIN OUTCOME MEASURE(S): Fertilization, cleavage, and pregnancy rates. INTERVENTION(S): Intracytoplasmic sperm injection and calcium ionophore. RESULT(S): This couple experienced only 7% fertilization after ICSI in their first cycle. Treatment of the unfertilized oocytes with calcium ionophore 20 hours after ICSI-induced fertilization and cleavage of 70% of the oocytes. Embryo quality was fair to good. On the second cycle, 8 of the injected oocytes were treated with ionophore immediately after ICSI and the remaining 20 oocytes were untreated. Normal fertilization was achieved in 75% of the treated and 10% of the untreated oocytes. Treatment of these unfertilized oocytes with ionophore 20 hours after ICSI resulted in fertilization in 73%. Pregnancy was not achieved after either ICSI cycle. Ultrastructural analysis indicated multiple structural abnormalities in the sperm. CONCLUSION(S): These results indicate that the round-headed sperm from this patient were incapable of oocyte activation after ICSI. This may be the reason for the frequent ICSI fertilization failure seen with this condition. Current ICSI procedures may not always overcome the infertility associated with globozoospermia, and further study of the etiology of this condition is needed.

Adult↗
PubMed2006

The effects of cryopreservation on the morphometric dimensions of Iberian red deer (Cervus elaphus hispanicus) epididymal sperm heads.

Computer-automated sperm-head morphometry was used in this study to determine the effects of cryopreservation on red deer sperm-head morphometry. Epididymal sperm samples were collected from 40 mature stags and were divided. One portion was diluted at room temperature in a Tris-citrate egg yolk medium, containing 6% glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for length, width, area, perimeter and shape factor (length/width), for a minimum of 135 spermatozoa were determined for each slide by means of the Sperm-Class Analyser (SCA). Firstly, our results show that cryopreservation substantially reduced (p < 0.001) sperm motility and plasma membrane and acrosome integrities. In addition, sperm heads were significantly smaller in cryopreserved spermatozoa than in the companion extended samples for area (32.05 microm2 vs 32.56 microm2; p < 0.05), length (8.46 microm vs 8.53 microm; p < 0.0001) and shape factor (1.833 vs 1.849; p < 0.0001) for all stags. These differences were found within 29 of 40 stags (75%) for at least three of the morphometric parameters. The individual variability (CV) of sperm head measurements from extended samples was negatively correlated (p < 0.005) with the per cent of change in sperm head measurements after cryopreservation for area (r = -0.465), width (r = -0.483) and perimeter (r = -0.375). Thus, the lower the sperm head variability in the extended samples, the greater the sperm change as a consequence of the cryopreservation. These results suggest that the variability (heterogeneity) in sperm head dimensions of individual stags may be a good indicator of sperm freezability.

Acrosome↗
PubMed2006

The effect of cryopreservation on sperm head morphometry in Florida male goat related to sperm freezability.

The Sperm Class Analyzer was used to investigate the effect of freeze-thawing procedure on Florida buck sperm head morphometry, and to relate possible changes in sperm head dimensions to cryopreservation success. Semen samples (n=76) were frozen with tris and milk-based extenders and thawed. Sperm quality samples (motility, morphology, acrosome), and sperm head morphometric values (length, width, area, perimeter, ellipticity) were compared between fresh and frozen-thawed samples. Sperm freezability was judged according to the sperm quality parameters assessed. Fertility data was obtained after artificial insemination with cryopreserved semen. Cryopreservation success was different between freezing methods. Sperm head dimensions were significantly (p<0.05) smaller in cryopreserved tris and milk spermatozoa respectively than in those of the fresh samples. The sperm head morphometric parameters that had changed after cryopreservation were lower in suitable semen samples after thawing and with successful pregnancies after artificial insemination. These data suggest that changes in sperm head morphometry might reflect spermatozoa injury occurred during cryopreservation.

Animals↗
PubMed2003

Effect of processing and measuring procedures on estimated sizes of bull sperm heads.

Reported estimates of sperm head size within a species vary considerably, partly due to procedural effects. A simple India ink method was developed that provided good contrast without inducing artifacts. Semen from five fertile bulls was smeared on replicate slides and left unfixed or fixed in Carnoys solution, with ink added for background. Other slides were fixed, and sperm were stained by the Feulgen procedure. Sperm head area was measured four ways. These were linear measurements made with the aid of an ocular micrometer and an oil immersion objective, plus three methods of measuring sperm heads projected at magnification 5,000 x. The areas of unfixed and fixed sperm heads did not differ (41.5 microm(2) versus 41.6 microm(2), respectively, P>0.05). The Feulgen-stained head area was smaller (26.2 microm(2), P<0.05). Sperm head areas calculated from ocular micrometer measurements were slightly smaller (P<0.05) than areas measured using projection. Identical results obtained by two technicians were treated as duplicates and approximately half of the variation was biological, due to source of semen. There was an interaction (P<0.05) between the sample source and fixation procedures. Thus, preparative techniques must be carefully controlled, and experiments designed to partition possible interactions between the biological material sampled and procedures used.

Animals↗
PubMed2006

Standardization of sample preparation, staining and sampling methods for automated sperm head morphometry analysis of boar spermatozoa.

The accuracy of computer-assisted sperm morphometry analysis (CASMA) depends on the careful preparation, fixation and staining of spermatozoa. The efficiency of CASMA may be enhanced by developing optimized protocols. The aim of the present study was to evaluate the influence of sperm washing and the use of three staining techniques [rapid Panoptic, Hemacolor and Harris's Haematoxylin (HH)] on image-processing accuracy and boar sperm head morphometry. Sperm washing had a significant effect on samples stained with rapid Panoptic, increasing the percentage of correctly binarized sperm heads and the contrast between cells and background. However, rapid Panoptic yielded the lowest percentage of properly digitized sperm heads. HH provided the highest cell/background contrast, and also greater sperm head staining intensity, but discrimination of sperm midpieces was considered insufficient. Hemacolor occupied an intermediate position, providing acceptable colour intensity and satisfactory cell/background contrast. Use of different staining procedures prompted dimensional differences in sperm head morphometry. Significant differences between animals were observed for all morphometric parameters. Low within-animal variation coefficients reflected a homogeneous sperm head population. Between-animal variation coefficients were relatively high for Hemacolor and HH, and significantly high for the rapid Panoptic stain. Using Panoptic and HH, stable morphometric measurements required at least 100 properly digitized sperm heads rather than 200, while Hemacolor required only 50 spermatozoa. These results indicate that both washing of semen and staining procedures significantly affect the accuracy of image processing and sperm head dimensions. Hemacolor and HH proved to be the best staining techniques for evaluating sperm head dimensions in boar.

Animals↗
PubMed2005

'Round head' sperm defect. Ultrastructural and meiotic segregation study.

The sperm 'round head' defect, also known as globozoospermia, is an uncommon alteration of sperm morphology generally characterised by 100% round headed sperm totally lacking an acrosome. This alteration is a genetic sperm defect as demonstrated by analysing the incidence of these alterations in a population of infertile men showing a history of consanguinity and cases belonging to the same family. Ultrastructural characteristics and meiotic segregation in spermatozoa from two patients affected by 'round head' sperm defect were investigated. The sperm quality was examined by light and transmission electron microscopy (TEM) and fluorescence in situ hybridization (FISH) analysis was performed in order to investigate the meiotic behavior of chromosomes namely gonosomes and chromosome 18. TEM analysis, mathematically elaborated, clearly diagnosed the 'round head' genetic sperm defect and highlighted at the same time the presence of other phenotypic alterations belonging to pathologies such as immaturity, apoptosis and necrosis. It is possible to hypothesize that round headed sperm could be a 'weak phenotype' allowing the sperm pathologies to overlap with a sperm defect of genetic origin, further compromising fertilizing potential. FISH analysis revealed a positive correlation between globozoospermia and higher disomies of sex chromosomes and diploidies suggesting a higher risk of creating an aneuploid embryo after intracytoplasmic sperm injection.

Adult↗
PubMed2006

Chromosomal analysis of spermatozoa with normal-sized heads in two infertile patients with macrocephalic sperm head syndrome.

OBJECTIVE: To study the chromosomal content of spermatozoa that could be selected for intracytoplasmic sperm injection (ICSI) in cases of macrocephalic sperm head syndrome. DESIGN: Case report. SETTING: Obstetrics, gynecology, urology, and reproductive biology departments. PATIENT(S): Two infertile patient candidates for ICSI presenting with total teratozoospermia (100%) with mainly large-headed spermatozoa (91% and 82%, respectively). INTERVENTION(S): Fluorescence in situ hybridization with X, Y, 18 centromeric probes on unselected spermatozoa (all migrated spermatozoa) and specifically on selected spermatozoa with normal-sized heads. MAIN OUTCOME MEASURE(S): Percentage of polyploid, diploid, aneuploid, and normal haploid spermatozoa, according to X, Y, 18 chromosome centromeric probes on selected spermatozoa (head size compatible with ICSI). RESULT(S): All the nonselected spermatozoa were abnormal, diploid, or polyploid. The rate of normal ploidy (haploid cells) among the selected sperm population was 1 per 28 for patient 1 and 5 per 51 for patient 2. CONCLUSION(S): This very low proportion of normal haploid spermatozoa among selected spermatozoa contraindicated ICSI for the two patients. We suggest performance of this selection and analysis before including (or not), in an ICSI program, patients with macrocephalic sperm head syndrome, associated or not with preimplantation genetic diagnosis.

Chromosome Aberrations↗
PubMed1994

A quantitative study of sperm head ultrastructure in subfertile males with excess sperm precursors.

OBJECTIVE: To make an objective comparison between sperm head ultrastructure in fertile subjects and a subfertile cohort with an excess of immature germinal elements in the ejaculate. DESIGN: A quantitative analysis of ultrastructural features of the sperm head using transmission electron microscopy in the defined groups. PATIENTS: Ten men of proven fertility as controls and 10 subfertile subjects with a persistent excess of sperm precursors in the ejaculate were investigated. SETTING: The Infertility Clinic at Queen Charlotte's and Chelsea Hospital, London. MAIN OUTCOME MEASURES: Each individual in the study achieved a score for a range of previously defined features of sperm head ultrastructure. These scores provided the basis for comparison between fertile and subfertile subjects. RESULTS: Subfertile individuals were found to have motile sperm with significantly more hypoplastic, detached, and abnormally shaped acrosomes than fertile controls. Sperm nuclei in these subjects also contained significantly more intranuclear vacuoles and immature chromatin and were associated more commonly with cytoplasmic droplets than fertile controls. CONCLUSION: Men with an excess of sperm precursors in the ejaculate have motile sperm with a range of abnormalities involving the nucleus and acrosome to account for reduced functional competence.

Acrosome↗