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Yanagida K 《Human cell》2004,17(4):187-194
Abstract  Fertilization failure is one of the causes of infertility that becomes evident only after in vitro fertilization (TVF) and intracytoplasmic sperm injection (ICSI) have been attempted. Although the frequency of incidence of fertilization failure is low, if fertilization failure is encountered, medical treatment is usually stopped and serious psychological damage may occur to the patient.
While fertilization failure in IVF can be dealt with using ICSI, there is no treatment for fertilization failure in ICSI. At present, clinical investigations are being conducted to evaluate oocyte activation in combination with ICSI to cope with fertilization failure of ICSI.  相似文献   

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The ubiquitin-proteasome system plays an important role in spermatogenesis. However, the functions of deubiquitinating enzymes in this process remain poorly characterized. We previously showed that the deubiquitinating enzyme USP2 is induced in late elongating spermatids. To identify its function, we generated mice lacking USP2. Usp2 -/- mice appeared normal, and the weights of major organs, including the testis, did not differ from wild type (Usp2 +/+). However, although the numbers of testicular spermatids and epididymal spermatozoa were normal in Usp2 -/- males, these animals had a severe defect in fertility, yielding only 12% as many offspring as Usp2 +/+ littermates. Spermatogenesis in Usp2 -/- mice was morphologically normal except for the presence of abnormal aggregations of elongating spermatids and formation of multinucleated cells in some tubules. The epididymal epithelium was morphologically normal in Usp2 -/- mice, but some abnormal cells other than sperm were present in the lumen. Usp2 -/- epididymal spermatozoa manifested normal motility when incubated in culture media, but rapidly became immotile when incubated in PBS in contrast to Usp2 +/+ spermatozoa, which largely maintained motility under this condition. Usp2 -/- and +/+ spermatozoa underwent acrosome reactions in vitro with similar frequency. In vitro fertilization assays demonstrated a severe defect in the ability of Usp2 -/- spermatozoa to fertilize eggs. This could be bypassed by intracytoplasmic sperm injection or removal of the zona pellucida, which resulted in fertilization rates similar to that of Usp2 +/+ mice. We demonstrate for the first time, using mouse transgenic approaches, a role for the ubiquitin system in fertilization.  相似文献   

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Sperm factors related to failure of human in-vitro fertilization   总被引:14,自引:0,他引:14  
Two groups of men were retrospectively selected according to their observed success in in-vitro fertilization. Seminal and post-migration sperm samples from a low fertilization rate group (less than or equal to 33% cleaved embryos) have been compared to results obtained from a high fertilization rate group (greater than or equal to 66%). It was found that a low mean value of the amplitude of lateral sperm head displacement and an increased percentage of abnormal acrosomes were related to in-vitro fertilization failure. None of the individual sperm factors studied was found to determine in-vitro fertilization success with certainty; only when they were considered in combination was it possible to predict the likelihood of successful in-vitro fertilization of human oocytes.  相似文献   

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Infecundity and subfertility among the rural population of Ethiopia   总被引:1,自引:0,他引:1  
A 1980-81 survey of the rural population of Ethiopia found high levels of infecundity and subfertility, although there was considerable variation by region, ethnicity and age of women. Higher levels of infecundity were geographically concentrated in a broad belt that ran from the south and south-west of the country, across to the north-east. The analyses suggest that infecundity is influenced by ecological factors, more than by ethnicity.  相似文献   

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Dilated cardiomyopathy, a disease of unknown etiology and pathogenesis, is associated with heart failure and compensatory hypertrophy. Although cell and animal models suggest a role for altered gene expression in the transition to heart failure, there is a paucity of data derived from the study of human heart tissue. In this study, we used DNA microarray profiling to investigate changes in the expression of genes involved in apoptosis that occur in human idiopathic dilated cardiomyopathic hearts that had progressed to heart failure. We observed altered gene expression consistent with a proapoptotic shift in the TNF-alpha signaling pathway. Specifically, we found decreased expression of TNF-alpha- and NF-kappaB-induced antiapoptotic genes such as growth arrest and DNA damage-inducible (GADD)45beta, Flice inhibitory protein (FLIP), and TNF-induced protein 3 (A20). Consistent with a role for apoptosis in heart failure, we also observed a significant decrease in phosphorylation of BAD at Ser-112. This study identifies several pathways that are altered in human heart failure and provides new targets for therapy.  相似文献   

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Molecular Biology Reports - Recurrent implantation failure (RIF) is diagnosed when good-quality embryos repeatedly fail to implant after transfer in several in vitro fertilization (IVF) treatment...  相似文献   

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Infertility affects one in 6 couples in developed nations, resulting in an increasing use of assisted reproductive technologies (ART). Both ART and subfertility appear to be linked to lower birth weight outcomes, setting infants up for poor long-term health. Prenatal growth is, in part, regulated via epigenetically-controlled imprinted genes in the placenta. Although differences in DNA methylation between ART and control infants have been found, it remains unclear whether these differences are due to the ART procedures or to the underlying parental subfertility and how these methylation differences affect imprinted gene expression. In this study, we examined the expression of 108 imprinted genes in placental tissues from infants born to subfertile parents (n = 79), matched naturally-conceived controls (n = 158), and infants conceived using in vitro fertilization (IVF, n = 18). Forty-five genes were identified as having significantly different expression between the subfertile infants and controls, whereas no significant differences were identified between the IVF and control groups. The expression of 4 genes—IGF2, NAPIL5, PAX8-AS1, and TUBGCP5—was significantly downregulated in the IVF compared with the subfertile group. Three of the 45 genes significantly dysregulated between subfertile and control placentae—GRB10, NDN, and CD44 —were found to have a significant positive correlation between expression and birth weight. Methylation levels for these 3 genes and 4 others—MKRN3, WRB, DHCR24, and CYR61—were significantly correlated with expression. Our findings indicate that epigenetic differences in placentas resulting from IVF pregnancies may be related to the underlying subfertility in parents using IVF rather than the IVF procedure itself.  相似文献   

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BACKGROUND: The subfertility of cryptorchidism correlates with severely reduced total germ cell counts in prepubertal testicular biopsies of undescended testes. Reduced total germ cell counts are associated with defects in the two prepubertal steps in maturation and proliferation in germ cells: first, the transformation of the fetal stem cell pool (gonocytes) into the adult stem cell pool (adult dark spermatogonia) at two to three months of age and, second, the transformation of adult dark spermatogonia into primary spermatocytes (meiosis) at 4-5 years. The defects in maturation are associated with blunting of the normal surges in gonadotropins and testosterone. Prepubertal treatment with gonadotropin-releasing hormones would theoretically trigger normal germ cell maturation and proliferation and thereby improve total germ cell counts and improve fertility. Prepubertal treatment of cryptorchidism with the GnRH analogue Buserelin has resulted in improved total germ cell counts and improved spermiograms. The purpose of this report is to describe the results of treatment of cryptorchidism with the GnRH analogue Naferelin. PATIENTS: Twelve boys with cryptorchidism, 6 unilateral and 6 bilateral, and severely reduced germ cell counts in testicular biopsies were treated with Naferelin following successful orchidopexy and bilateral testicular biopsies. Response of the total germ cell counts was assessed in follow-up bilateral biopsies within 5 months of completing the hormonal therapy. RESULTS: Eight of the 12 boys (5 of the 6 with unilateral and 3 of the 6 with bilateral cryptorchidism) showed improvement in the total germ cell counts in one or both testes. All 8 had a poor prognosis for fertility pretreatment and a good prognosis for fertility posttreatment. Of the 5 with unilateral cryptorchidism who improved, 2 showed improvement in both testes; and 3, only in the contralateral descended testes. All 3 of the boys with bilateral cryptorchidism who improved showed improvement in both testes. Testes with absence of germ cells and older patients tended to show no improvement. Of the 6 contralateral descended, 5 (83%) improved, and of the 18 undescended testes, 8 (44%) improved. CONCLUSIONS: In this preliminary study, Naferelin therapy appears to induce improvement in the total germ cell counts and the prognosis for future fertility in 75% of patients.  相似文献   

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