[Haploidisation of somatic cells].
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
G D Palermo
Publications and source records attributed to G D Palermo.
Intracytoplasmic sperm injection. Accomplishments and qualms.
AIM: Intracytoplasmic sperm injection (ICSI) is now the preferred technique for treatment of male factor infertility and many children have been born worldwide. However, concerns about the risk of transmitting genetic defects and development of ICSI children have been raised. We report clinical outcome of ICSI in Cornell University and results of screening for genetic defects in ICSI parents and their children. METHODS: Pregnancy and obstetrical outcomes as well as congenital malformations were analyzed. Chromosomal karyotyping and Yq deletion assessments were performed on blood samples. In addition, medical and developmental outcome were assessed in 3 and 5 year old ICSI children. RESULTS: We have performed 8 575 ICSI cycles with ejaculated spermatozoa that resulted in a 75.4% fertilization and a 42.8% clinical pregnancy rates while for surgically retrieved specimen resulted in 66%, 48.8% respectively. The incidence of Y deletion was within the expected range for an infertile population, with identical deletions transmitted to the male offspring. There were no differences in cognitive, motor and behavioral development observed between ICSI children and these conceived naturally. CONCLUSION: The large majority of infertile men were treatable by ICSI, which resulted in the transmission of a specific abnormality but did not enhance the incidence of de novo deletions. There is no indication that ICSI children develop more congenital defects or express a lower psychomotor development that children conceived naturally. Nonetheless, genetic screening and counseling of couples undergoing ICSI would seem to be appropriate.
Adult↗
Application of intracytoplasmic sperm injection in assisted reproductive technologies.
Intracytoplasmic sperm injection (ICSI) entails the mechanical insertion of a chosen spermatozoon directly into the cytoplasm of an oocyte. Due to the consistent fertilization and pregnancy outcome, ICSI is routinely used to treat azoospermic patients where spermatozoa are retrieved by epididymal aspiration or testicular biopsy. Since male subfertility has been associated with a higher incidence of genomic defects, ranging from numerical chromosomal abnormalities to Yq microdeletions, concerns have been raised as to the risk of transmitting genetic defects to the offspring. Screening for such defects can provide invaluable information for appropriate counselling prior to ICSI treatment. In order to address these concerns, a follow-up of the children born after ICSI treatment was conducted.
Adult↗
Detection of sperm in men with Y chromosome microdeletions of the AZFa, AZFb and AZFc regions.
BACKGROUND: Y chromosome microdeletions are associated with severe male factor infertility. In this study, the success rate of testicular sperm retrieval was determined for men with deletions of AZF regions a, b or c. METHODS: AZF deletions were detected by PCR of 30 sequence-tagged sites within Yq emphasizing the AZFa, b and c regions. Semen analysis and diagnostic testis biopsy or testicular sperm extraction (TESE) findings were correlated with the specific AZF region deleted. RESULTS: A total of 78 men with AZF deletions included three with AZFa deletion, 11 with AZFb, 42 with AZFc, 16 with AZFb+c and six with Yq (AZFa+b+c). All men with AZFa, AZFb, AZFb+c and Yq deletions were azoospermic and no sperm were found with TESE or biopsy. Of men with isolated AZFc deletion, sperm were found in 75% (9/12) by TESE and 45% (9/20) on biopsy (56% overall); 62% (26/42) were azoospermic and 38% (16/42) severely oligozoospermic. A total of 7 patients with deletion patterns that included the complete AZFa region and 23 that included the complete AZFb region who underwent TESE or biopsy did not have sperm detected by these surgical measures. CONCLUSIONS: Microdeletion of the entire AZFa or AZFb regions of the Y chromosome portends an exceptionally poor prognosis for sperm retrieval, whereas the majority of men with AZFc deletion have sperm within the semen or testes available for use in IVF/ICSI.
Adult↗
Absence of profound hyperinsulinism in polycystic ovary syndrome is associated with subtle elevations in the plasminogen activator inhibitor system.
In order to describe potential hypofibrinolytic tendencies in young (< 35 years) polycystic ovary syndrome (PCOS) patients, we studied plasminogen activator inhibitor (PAI-1) system components in women without laboratory evidence of hyperinsulinism or hyperandrogenism. The study was a prospective, observational comparison and took place in a major urban infertility referral center. Age, body mass index, ovulatory status, selected androgen levels, fasting insulin and plasma lipids were measured in subjects with PCOS (n = 39) and normal control subjects (n = 20). Women with PCOS had higher mean serum total testosterone and androstenedione levels compared with controls (56.4 versus 40.3 ng/dl, p = 0.03, and 179 versus 133 microg/ml, p = 0.03, respectively). Mean fasting insulin levels were higher among PCOS women (p < 0.01) and were strongly correlated with PAI-1 antigen (Ag) (r = 0.46), PAI-1 activity (r = 0.43), and tissue plasminogen activator (t-PA) (r = 0.5). Correlations were evident in both PCOS and control subjects. Mean PAI-1 Ag, PAI-1 activity, and t-PA levels were significantly elevated (p = 0.003, 0.001, and 0.001, respectively) in PCOS. ANOVA was performed to control for insulin effect; a trend toward elevated PAI-1 in PCOS persisted but was no longer statistically significant (p = 0.24). PAI-1 activity elevation remained in PCOS women with mean fasting insulin levels < 10 mIU/ml (p = 0.02), yet the difference became less significant when insulin was controlled (p = 0.38). Although these data confirm known associations between insulin and PAI-1 derangements, this is the first study to quantify discrete PAI-1 elevations that persist in the setting of PCOS even with normal or low ambient insulin levels. Additional prospective studies are needed to determine whether this altered PAI-1 state is associated with a clinically important hypofibrinolytic condition and subsequent poor reproductive outcome.
Adult↗
Testicular sperm extraction combined with intracytoplasmic sperm injection in the treatment of men with persistent azoospermia postchemotherapy.
BACKGROUND: Men who remain azoospermic long after undergoing chemotherapy have generally been considered sterile. The authors report their experience with testicular sperm extraction (TESE) combined with intracytoplasmic sperm injection (ICSI) applied to azoospermic men who previously received chemotherapy for a variety of indications. METHODS: Among 231 cycles in 198 patients who underwent TESE-ICSI for nonobstructive azoospermia from 1995 to 2000, 20 TESE procedures in 17 patients who previously received chemotherapy were identified. All TESE procedures were performed with microsurgical control under local anesthesia with sedation or general anesthesia. The pretreatment hormonal profile, histology of testicular biopsies, and outcomes of TESE-ICSI in this subgroup of patients were analyzed. RESULTS: The mean patient age was 37.4 years (range, 28-54 years), and the mean follicle-stimulating hormone level was 21.8 mIU/mL (range, 7.1-43.1 mIU/mL). The mean age for female partners was 33.5 years (range, 22-43 years). Six patients had received chemotherapy for Hodgkin lymphoma (34%), four patients had received chemotherapy for testicular neoplasm (24%), two patients had received chemotherapy for non-Hodgkin lymphoma (12%), two patients had received chemotherapy for leukemia (12%), one patient had received chemotherapy for Wilms tumor (6%), one patient had received chemotherapy for mediastinal germ cell tumor (6%), and one patient had received chemotherapy for nephrotic syndrome (6%). Three patients (18%) received additional radiation therapy. The mean interval from chemotherapy to TESE was 16.3 years (range, 6-34 years). All patients had at least two semen analyses to confirm azoospermia. A total of 20 attempts of TESE-ICSI were performed (mean, 1.2 attempts per patient). Testicular histology revealed Sertoli cell-only pattern in 76% of patients. The remaining 24% of patients had hypospermatogenesis as their most advanced spermatogenic pattern. Among the men with Sertoli cell-only pattern, 23% had sperm retrieved by TESE. Sperm retrieval was accomplished in 9 of 20 attempts (45%), with biochemical pregnancy after sperm retrieval in 4 of 9 couples (45%) and clinical pregnancy in 3 of 9 couples (33%). Live deliveries were achieved in 2 of 9 couples (22%). Two healthy boys and one girl were delivered. No correlation was noted between the outcome of TESE-ICSI and the underlying conditions that were treated with chemotherapy nor with the chemotherapeutic agents used. CONCLUSIONS: Using TESE-ICSI, sperm retrieval leading to pregnancy and the delivery of healthy children is possible for men with long-standing azoospermia after chemotherapy. The prognosis for sperm retrieval was not influenced clearly by the chemotherapy regimen or the disease treated. Diagnostic biopsy also was of limited value in predicting the outcome of sperm retrieval. Despite prolonged nonobstructive azoospermia after undergoing chemotherapy, men no longer should be considered sterile in the era of advanced assisted reproductive techniques.
Adult↗
Reprogramming somatic cell differentiation and the Hayflick Limit: contrasting two modern molecular bioengineering aims and their impact on the future of mankind.
The molecular biology of human cloning and aging research depend on the closely related laboratory techniques supported by a thorough understanding of cell-signaling processes. Unfortunately, the link between these two research fields has received only marginal attention in the lay press. Cloning is possible when somatic cell differentiation is successfully reprogrammed, and clinical control of cellular senescence depends on a proper reconfiguration of the predetermined number of divisions permitted during the cell life-cycle (the so-called "Hayflick Limit"). In this paper, we discuss these two concepts and compare the impact likely to be associated with bioengineering studies that facilitate both human cloning and longevity therapy.
Aging↗
Successful ovulation induction, conception, and normal delivery after chronic therapy with etanercept: a recombinant fusion anti-cytokine treatment for rheumatoid arthritis.
Etanercept (Enbrel; Wyeth-Ayerst/Immunex Inc, Seattle, WA, USA) is a subcutaneously administered novel fusion protein consisting of the extracellular ligand-binding domain of the 75 kD receptor for tumor necrosis factor-alpha (anti-TNFalpha) and the Fc portion of human IgG1. The agent is synthesized by plasmid transfection of a Chinese hamster ovary cell line, utilizing recombinant DNA technology. Etanercept was approved by the US FDA for treatment of multi-drug resistant rheumatoid arthritis in 1998, but no human data exist regarding the impact of anti-TNFalpha therapy on human reproductive function or its use before ovulation induction. As TNFalpha potentiates collagenolysis via matrix metalloproteinase gene expression (thereby facilitating ovulation), there exists a theoretical risk that TNFalpha-inhibition could exert an undesirable effect on ovulation and pregnancy. In this report, we describe the first case of ovulation induction, intrauterine insemination, normal pregnancy and singleton delivery of a healthy infant following chronic ( > 1 year) pre-ovulatory TNFalpha-inhibitor therapy for rheumatoid arthritis. Reproductive endocrinologists and obstetrician-gynecologists should be familiar with etanercept therapy in the context of severe rheumatic disease, and offer appropriate reassurance regarding its safe use for infertility patients planning ovulation induction.
Adult↗
Preliminary findings in germinal vesicle transplantation of immature human oocytes.
Transplanting a germinal vesicle (GV) from an aged woman's oocyte into a younger ooplasm has been proposed as a possible way to reduce the incidence of oocyte aneuploidy which is considered to be responsible for age-related infertility. In this study, we have assessed the efficiency of each step involved in nuclear transplantation-specifically cell survival, nuclear-cytoplasmic reconstitution, and the capacity of the reconstituted oocytes for in-vitro maturation. In addition, we have evaluated the fertilizability and karyotypic status of the manipulated oocytes by intracytoplasmic sperm injection (ICSI) and fluorescent in-situ hybridization technique respectively. Nuclear transplantation was accomplished with an overall efficiency of 73%. Due to the limited availability of materials, most nuclear transplantation procedures were performed between sibling oocytes. The maturation rate of 62% following reconstitution was comparable with that of control oocytes, as was the incidence of aneuploidy among the reconstituted oocytes. The ICSI results of the reconstituted oocytes yielded a survival rate of 77%, a fertilization rate of 52%, and a satisfactory early embryonic cleavage. Furthermore, in a limited number of observations where the nucleus of an aged oocyte was transferred into a younger ooplasm, there was an appropriate chromosomal segregation. These findings demonstrate that human oocytes reconstituted with GV nuclei are able to undergo maturation, fertilization, and early embryo cleavage, and maintain a normal ploidy. Although in-vitro maturation seems to be a limiting step, this technique would allow us to investigate further the nuclear-ooplasmic relationship during meiotic maturation.
Adult↗
Use of electively cryopreserved microsurgically aspirated epididymal sperm with IVF and intracytoplasmic sperm injection for obstructive azoospermia.
OBJECTIVE: To investigate the efficacy of using intentionally cryopreserved epididymal sperm in selected cases of obstructive azoospermia. DESIGN: A retrospective, nonrandomized study. SETTING: Academic research environment. PATIENTS: One hundred forty-one couples undergoing first-time IVF/ICSI using either fresh or cryopreserved epididymal sperm. INTERVENTIONS: The epididymides were microsurgically aspirated. MAIN OUTCOME MEASURES: Clinical pregnancy rates. RESULTS: Motile sperm were obtained from all men. For the fresh group, the mean total sperm aspirated was 99 x 10(6) with 5.5 vials frozen per patient after ICSI and 82 x 10(6) with 4.7 vials frozen per patient in the cryopreserved group. No statistically significant difference in oocyte fertilization rate or number of embryos transferred was noted between groups. Of 108 patients using freshly aspirated sperm, 72 (66.7%) achieved clinical pregnancy. Of 33 patients in the group using cryopreserved sperm, 20 (60.6%) achieved clinical pregnancy (P=0.47). CONCLUSIONS: In selected ideal cases of unreconstructable azoospermia, elective open microsurgical epididymal sperm aspiration with cryopreservation yields pregnancy rates similar to that employing fresh sperm. The advantages of this method are: (1) Use of cryopreserved sperm obviates the logistics problems associated with the use of fresh sperm. (2) Abundant high-quality sperm can be cryopreserved in a single procedure for all future attempts at IVF/ICSI. Rarely, viable sperm will not be present after thawing, and fresh retrieval will be necessary.
Cryopreservation↗
Correction of hyperinsulinemia in oligoovulatory women with clomiphene-resistant polycystic ovary syndrome: a review of therapeutic rationale and reproductive outcomes.
Polycystic ovary syndrome (PCOS) describes a convergence of chronic multisystem endocrine derangements, including irregular menses, hirsutism, obesity, hyperlipidemia, androgenization, large and cystic-appearing ovaries, insulin resistance and subfertility. Few PCOS patients exhibit all of these features, and often only one sign or symptom is evident. The sequelae of PCOS reach beyond reproductive health, as women affected with PCOS have increased relative risks for myocardial infarction, hypertension, ischemic heart disease, thromboembolic disease and diabetes. Although the adverse health consequences associated with PCOS are substantial, unfortunately most women are not aware of these risks. Indeed, in infertility practice such concerns are secondary as most patients are referred for treatment specifically to achieve a pregnancy. Impairments in insulin metabolism appear central to the physiologic cascade of PCOS, yet clomiphene therapy fails to remedy this defect. Several investigators have described satisfactory reproductive outcomes for PCOS patients treated with oral insulin-lowering agents. In this report, we outline a diagnostic and therapeutic approach for women with PCOS refractory to clomiphene with attention to the underlying insulin imbalance associated with impaired fertility.
Clomiphene↗
Xenogeneic transplantation of human spermatogonia.
In the last 3 years, several studies have shown that xenogeneic transplantation of rodent spermatogonia is feasible. The treatment of infertile patients with spermatogenic arrest using the injection of immature germ cells has yielded only poor results. We attempted to establish a complete spermatogenetic line in the testes of mutant aspermatogenic (W/Wv) and severe combined immunodeficient mice (SCID) transplanted with germ cells from azoospermic men. Spermatogenic cells were obtained from testicular biopsy specimens of men (average age of 34.3 +/- 9 years) undergoing infertility treatment because of obstructive and non-obstructive azoospermia. Testicular tissue was digested with collagenase to promote separation of individual spermatogenic cells. The germ cells were injected into mouse testicular seminiferous tubules using a microneedle (40 microm inner diameter) on a 10 ml syringe. To assess the penetration of the cell suspension into the tubules, trypan blue was used as an indicator. Mice were maintained for 50 to 150 days to allow time for germ cell colonisation and development prior to them being killed. Testes were then fixed for histological examination and approximately 100 cross-sectioned tubules were examined for human spermatogenic cells. A total of 26 testicular cell samples, 16 frozen and 10 fresh, were obtained from 24 men. The origin of the azoospermia was obstructive (OA) in 16 patients and non-obstructive (NOA) in 8 patients. The concentration of spermatogenic cells in the OA group was 6.6 x 10(6) cells/ml, and 1.3 x 10(6) cells/ml in the NOA group (p < 0.01). The different spermatogenic cell types were distributed equally in the OA samples, ranging from spermatogenia to fully developed spermatozoa, but in the NOA group the majority of cells were spermatogonia and spermatocytes. A total of 23 testes from 14 W/Wv mice and 24 testes from 12 SCID mice were injected successfully, as judged by the presence of spermatogenic cells in histological sections of testes removed immediately after the injection. However, sections from the remaining testes examined up to 150 days after injection showed tubules lined with Sertoli cells and xenogeneic germ cells were not found. The reason why the two strains of mouse used as recipients did not allow the implantation of human germ cells is probably due to interspecies specificity involving non-compatible cell adhesion molecules and/or immunological rejection.
Adult↗
ICSI and its outcome.
Since its introduction in 1992, intracytoplasmic sperm injection (ICSI) has become a popular assisted fertilization technique proved very efficient in treating male factor infertility. Many healthy children have been born worldwide from this procedure, and their physical and mental development appears to be within the normal limits. However, because of the peculiarity of the technique and the poor characteristics of the spermatozoa used, concern about the safety of ICSI still exist. In this article, we analyze the in vivo development of embryos conceived after ICSI as well as the obstetric outcome, occurrence of chromosomal abnormalities, and rate of congenital malformations in neonates born as a result of this treatment. A total of 2435 couples were studied in whom the male partners were presumed to be the cause of repeated failed attempts at in vitro fertilization (IVF) or had semen parameters that were unacceptable for conventional IVF treatment. Pregnancies resulting from 3573 ICSI cycles were analyzed; pregnancy outcome data were obtained from the records of obstetrician-gynecologists and/or pediatricians. The overall clinical pregnancy (fetal heartbeat) rate was 44.8% with a resultant delivery rate of 39.2% per ICSI cycle (n = 1388). In 37 of the 77 miscarriages for which cytogenetic data were available, an autosomal trisomy was found in each and 29 additional pregnancies were terminated because of a chromosomal abnormality revealed by prenatal diagnosis. There was an equal distribution of vaginal deliveries and cesarean sections (n = 682 and n = 658, respectively). Of the 2059 neonates resulting from ICSI treatment, 38 (1.8%) presented with congenital abnormalities (22 major and 16 minor). When the frequency of miscarriages and congenital malformations was analyzed in terms of semen origin, the outcome was no different between ICSI and IVF. The course of pregnancies and occurrence of congenital malformations following treatment by ICSI are within the ranges obtained following conventional IVF.
Abortion, Spontaneous↗
Human zona pellucida micromanipulation and monozygotic twinning frequency after IVF.
To assess the association of zona pellucida micromanipulation and subsequent development of monozygotic twins, cases of assisted embryo hatching (AH) and intracytoplasmic sperm injection (ICSI) were identified and related to treatment type, implantation and zygosity data. Embryology records from all patients undergoing in-vitro fertilization (IVF) at this centre from January 1995 to March 1998 were reviewed. In this study, 3546 transfer cycles were completed, with clinical pregnancy established in 1911 (54% per transfer) patients undergoing a single IVF cycle. These pregnancies occurred in 1674 (88%) IVF cycles, 120 (6%) donor oocyte cycles (DER), and 117 (6%) frozen embryo transfer (FET) cycles. During the study period, 23 cases of monozygotic (MZ) twins were identified, representing an overall frequency of 1.2%. Chorionicity was determined by transvaginal ultrasound at 7 weeks when the number of embryos transferred was less than the number of fetal heart-beats, or when >1 fetal heartbeat per gestational sac was seen. Zygosity was confirmed by placental evaluation at delivery, and corroborated the antenatal diagnosis in all cases. Among IVF study patients the frequency of MZ twinning was not statistically different between zona manipulated and zona intact subgroups. While this investigation is the largest to date describing the relationship between MZ twins and zona procedures, studies with even greater statistical power are needed to clarify it more precisely, particularly in DER and FET settings. A greater overall frequency of MZ twinning for IVF patients may be a function of the higher number of embryos transferred in IVF, rather than discrete zona manipulations.
Embryo Transfer↗
Alternative sources of gametes: reality or science fiction?
Although great progress has been made in both the investigation and treatment of infertility, a considerable number of patients still fail to conceive. Spermatogenic failure and/or oocyte ageing appear to be responsible for a large proportion of cases. The use of donor gametes may bring legal, ethical and even social problems of acceptance that can discourage infertile couples from the donor route. Fortunately, emerging reproductive technologies and preliminary results from animal experiments provide some hope for alternative sources of gametes through which these infertile patients can finally conceive their own genetic child. In conjunction with intracytoplasmic sperm injection (ICSI), fertilization of human oocytes with immature sperm precursors, e.g. spermatids and even secondary spermatocytes, has resulted in healthy babies. Pregnancies have also resulted from the use of spermatids derived from in-vitro spermatogenesis. In the mouse, even primary spermatocytes appear able to participate in normal embryogenesis. In view of the possibility for transplantation and even xenotransplantation of spermatogonia to a host testis in animals, a similar use of human male stem cells might provide an attractive source for the treatment of males with arrested spermatogenesis, as well as male cancer patients. Transplantation of somatic cell nuclei and their haploidization within oocytes may prove to be a practical way of eradicating age-related aneuploidy and so constitute an innovative source of healthy oocytes. Most importantly, however, the safety of the procedures described here needs to be proven before their application to the human arena. Finally, we discuss the implications of cytoplasmic quality and of genetic imprinting in the context of these manipulations.
Animals↗
Assisted reproductive technologies and monozygous twins: implications for future study and clinical practice.
That the zona pellucida (ZP) plays a prominent role in the physiology of some human twinning is an attractive, albeit incompletely proven, medical hypothesis. Indeed, an association has been proposed between manipulation of the ZP and/or native ZP microarchitecture and monozygotic (MZ) twins. Ovulation induction also has been theoretically linked to in vivo ZP alterations facilitating MZ twin development. In vitro fertilization (IVF) relies on necessary (and, in some cases extended) embryo culture techniques potentially creating subtle ZP changes and subsequent MZ twinning. With growing experience in the assisted reproductive technologies and particularly IVF, some preliminary reports have noted an increased frequency of MZ twins after procedures that artificially breach the ZP (i.e., intracytoplasmic sperm injection [ICSI], or 'assisted hatching'). Such ZP manipulations ostensibly enhance oocyte fertilization or facilitate blastocyst hatching, thus improving pregnancy rates for couples undergoing fertility treatment. Evidence exists both to challenge and support the connection between these phenomena and MZ twins. This report outlines the fundamental embryological processes believed responsible for these conflicting observations; the current literature on the subject of human ZP micro-manipulation and MZ twins is also discussed.
Female↗
Human glucosamine-6-phosphate isomerase, a homologue of hamster oscillin, does not appear to be involved in Ca2+ release in mammalian oocytes.
Injections of cytosolic preparations from mammalian sperm into oocytes have been shown to trigger calcium [Ca2+]i oscillations and initiate activation of development. Recently, a protein isolated from hamster sperm has been suggested to be involved in the generation of these oscillations and it was named "oscillin." The human homologue of hamster oscillin is glucosamine 6-phosphate isomerase (GPI, EC no. 5.3.1.10), an enzyme so far described to be involved in hexose phosphate metabolism. To assess the role of GPI on Ca2+ signaling, a human recombinant protein was generated in a prokaryotic system and injected into fura-2-dextran-loaded metaphase II (MII) mouse oocytes. Injection of recombinant GPI failed to induce Ca2+ responses in 12/12 injected MII oocytes despite the fact that the recombinant GPI was active as assessed by an enzymatic assay. Injection of buffer (0/6 oocytes) or fructose-6-phosphate, a product of GPI enzymatic reaction (0/5 oocytes), also failed to initiate Ca2+ responses. Conversely, injections of sperm cytosolic factor induced [Ca2+]i oscillations in all 17/17 oocytes. In addition, injection of recombinant GPI or GPI mRNA failed to induce parthenogenetic activation (0/30 oocytes). Immunofluorescence studies using an anti-GPI polyclonal antibody (GK) resulted in localization of GPI to the sperm's equatorial region. Incubation of the GK antibody with sperm extracts failed to block the [Ca2+]i responses induced by these extracts. Moreover, near complete depletion of GPI from sperm fractions by immunoprecipitation did not impair the ability of these fractions to induce [Ca2+]i oscillations. In summary, our results support the role of a sperm cytosolic component(s) in the generation of [Ca2+]i oscillations during mammalian fertilization, although a protein other than GPI/oscillin is likely to be the active calcium releasing factor.
Aldose-Ketose Isomerases↗
Incidence of sperm aneuploidy in relation to semen characteristics and assisted reproductive outcome.
OBJECTIVE: To evaluate the incidence of sperm aneuploidy in men screened for infertility and identify any eventual relation with assisted reproductive outcome. DESIGN: Controlled prospective study. SETTING: University hospital-based IVF program. PATIENT(S): Infertile couples who were screened for sperm aneuploidy and evaluated for IVF treatment. INTERVENTION(S): Fluorescence in situ hybridization was used to identify chromosomes 18, 21, X, and Y. The assisted reproductive techniques of IVF and intracytoplasmic sperm injection were used for infertility treatment. MAIN OUTCOME MEASURE(S): The incidence of sperm aneuploidy, semen parameters, fertilization rate, pregnancy characteristics, and rate of neonatal malformations were determined. RESULT(S): Oligozoospermic and teratozoospermic men had a significantly higher incidence of chromosomal abnormalities than men with normal semen parameters (2.7% vs. 1.8%). The increased frequency of sperm aneuploidy did not appear to affect pregnancy losses or the occurrence of neonatal malformations. CONCLUSION(S): Suboptimal semen samples had a higher incidence of aneuploidy. In this study, the increased frequency of chromosomal abnormalities did not have a direct effect on the fertilization rate, pregnancy characteristics, or neonatal outcome.
Adult↗