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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 541 (1988), S. 0 
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of assisted reproduction and genetics 4 (1987), S. 107-110 
    ISSN: 1573-7330
    Keywords: in vitro fertilization ; human menopausal gonadotropins ; luteinizing hormone release ; estradiol levels ; hypothalamic pituitary axis ; follicle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This study demonstrates that luteinizing hormone (LH) release may occur despite sustained elevations of estradiol E2 in women receiving human menopausal gonadotropin. Mean levels of E2 did not correlate with the LH surge, however, the follicle number and a rapid rise in E2 did. Therefore, it appears that the protective influence of inhibitory proteins secreted by multiple follicles can be overridden, allowing spontaneous LH release.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Journal of assisted reproduction and genetics 4 (1987), S. 153-158 
    ISSN: 1573-7330
    Keywords: serum ; fractions ; effects ; in vitro fertilization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To examine the effect of various fractions of human fetal cord serum (HCS) on mouse embryos cultured in vitro, heat-inactivated HCS was separated by ultrafiltration into five distinct fractions: Fractions A, MW〉30,000; B, MW 30,000−10,000; C, MW 10,000−5000; D, MW 5000−1000; and E, MW 〈1000. Seven hundred twentyeight single-cell embryos were cultured in TYH- 280 medium supplemented with 8 mg/ml bovine serum albumin (BSA) and a 20% concentration of Fraction A, B, C, D, or E, whole HCS, or BSA alone. Embryos cultured with Fraction A or E or whole HCS demonstrated a significantly reduced growth rate (P〈0.01), while embryos cultured with Fraction D demonstrated a significantly increased growth rate (P〈0.01). Additionally, 649 singlecell embryos were cultured in medium which was supplemented with 8 mg BSA/ml and a 0, 1,2, or 5% concentration of Fraction A or E. Fraction E displayed toxicity even at a 1% concentration (P〈 0.07), while Fraction A demonstrated growth inhibition at a 5% concentration (P 〈0.05) but increased the hatching rate at a 1% concentration (P 〈 0.01). Finally, 635 single-cell embryos were cultured with four distinct fractions of HCS obtained from a Sephacryl S-200 column: Fractions I, MW 100,000; II, MW 70,000−100,000; III, MW 30,000−70,000; and IV, low molecular weight (〈5000). Fraction I or III significantly reduced the embryo growth rate as seen with Fraction A (P〈0.01) and Fraction II significantly increased only the hatching rate (P〈0.01), while Fraction IV significantly increased the growth rate as seen with Fraction D. In conclusion, HCS contains embryo growth inhibitory properties in the high (〉30,000) and low (〈1000) molecular weight components, while growth promoting factors are found in the 1000−5000 MW fraction. It also seems that there are some factors in the 70,000−100,000 MW fraction which may promote the ability of the embryo to hatch.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1573-7330
    Keywords: follicular fluid ; oocyte ; maturation ; pregnancy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Mouse zygotes were cultured in medium containing follicular fluid from patients who had follicles containing oocytes which fertilized, did not fertilize, or were atretic and who did or did not become pregnant after in vitro fertilization and embryo replacement. The inhibitory effect was least with the follicular fluid from follicies in which the oocytes subsequently fertilized, greater when the oocytes did not fertilize, and most inhibitory when the follicle contained an atretic oocyte. More mouse zygotes developed to blastocysts when culture medium was supplemented with follicular fluid from patients who became pregnant compared to those who did not become pregnant. There was no difference in pregnancy outcome when an oocyte which subsequently fertilized was obtained from the follicle. These results indicate that follicles contain a substance(s) which inhibits mouse zygote development in vitro and that the inhibitory activity is related to the developmental potential of the oocyte in the follicle.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1573-7330
    Keywords: OMI ; follicular fluid ; hMG
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Since removal of the oocyte from the intrafollicular milieu allows meiotic resumption and germinal vesical breakdown to proceed, the concept of an intrafollicular oocyte maturation inhibitor (OMI) has evolved. Accordingly, we asked the following questions: Is there OMI activity in human follicular fluid? Does OMI activity change with ovarian hyperstimulation? and Does OMI activity correlate with oocyte fertilization or the concentration of steroids in the corresponding follicular fluid? Fresh cumulus enclosed porcine oocytes from small follicles were incubated with human follicular fluid aspirates from normally menstruating patients with or without treatment: unstimulated follicles (N=10), clomiphene citrate (150 mg/day) (N=10)-treated cycles, and human menopausal gonadotropin (hMG) (N=12)-treated cycles. A lyophylized porcine follicular fluid standard and serum-free culture media were used as positive and negative controls, respectively. After a 40-hr incubation with test materials, the oocytes were fixed, stained, and evaluated for oocyte maturation as determined by germinal vesical breakdown. Human follicular fluid, estradiol, progesterone, androstenedione, and testosterone levels were determined by radioimmunoassay. The 50% inhibitory dose (ID50) for OMI activity in follicular fluid from untreated, spontaneously menstruating women was less than that for follicular fluid from clomiphene-stimulated patients, which was less than that for follicular fluid from hMG-stimulated patients. The difference between OMI values from untreated and hMG-stimulated follicular fluids was statistically significant. Human oocytes removed from follicular fluid with higher OMI activity tended not to fertilize in vitro compared to the relatively lower OMI activity present in follicular fluid yielding oocytes which did fertilize. However, these differences were not significant. Although there were no significant correlations between any of the follicular fluid concentrations of sex steroids and OMI activity, there was a trend toward higher androgen levels in follicular fluid with higher OMI activity. These findings lend support to the hypothesis that immature, nonfertilizable follicles obtained from spontaneously cycling women with or without exogenous gonadotropin treatment contain higher OMI activity levels than mature, fertilizable follicles.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1573-7330
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary While the Pantex direct P radioimmunoassay is used widely in programs of assisted conception, its sensitivity and range do not encompass the wide range of levels of P in serum of many patients during COH and through the first trimester of pregnancy. The present communication details minor modifications to the proprietary Pantex assay which accommodate these requirements. The nature of the changes does not compromise the performance characteristics or simplicity of the original assay and facilitates precise, accurate, and rapid measurement of serum P between 0.05 and 1280 ng/ml.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of assisted reproduction and genetics 1 (1984), S. 263-266 
    ISSN: 1573-7330
    Keywords: plasminogen activator ; ovarian hyperstimulation ; folliculogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Recently, it has been shown that granulosa-cell secretion of plasminogen activator (PA) is responsive to luteinizing hormone (LH)/human chorionic gonadotropin (hCG) as well as follicle stimulating hormone (FSH) in the rat and the pig. Accordingly, we asked whether PA activity in follicular fluid from exogenously stimulated human follicles was different from that of normal cycles and whether or not these activities correlated with follicular maturation as determined by follicular fluid steroid concentration. Follicular aspirates were obtained from women who were participating in an in vitro fertilization protocol. Follicular fluid concentrations of estradiol and progesterone were determined by established radioimmunoassay. PA activity, determined using a modified indirect solid-phase radioassay, was significantly less in follicles from patients treated with human menopausal gonadotropin (hMG) plus clomiphene (P〈0.05) compared to untreated patients or those receiving hMG or clomiphene alone. Correlations of PA activity and follicular fluid steroid concentrations demonstrated no significant correlation in samples from treated patients. In contrast, untreated spontaneously cycling patients had a significant (r=0.89,P〈0.05), positive correlation between follicular fluid estradiol levels. There was no correlation between PA activity and follicular fluid progesterone levels in any of the groups. These results suggest that a subtle balance in granulosa-cell secretion of PA and steroids exists, which appears to be disrupted by follicular hyperstimulation during treatment of patients participating in in vitro fertilization protocols.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of assisted reproduction and genetics 3 (1986), S. 353-357 
    ISSN: 1573-7330
    Keywords: sister-chromatid exchange ; chromosomal aberration ; triploidy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effect of increasing doses of exogenous gonadotropin stimulation for ovarian hyperstimulation was studied utilizing mouse embryos fertilized in vivo or in vitro. Increased rates of embryo degeneration, fragmentation, and triploidy, increased sister-chomatid exchange, and decreased fertilization rates were observed in high-dose stimulation groups. It appears, therefore, that oocyte and/or embryo quality may be affected by increased amounts of exogeneous gonadotropin stimulation.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1573-7330
    Keywords: luteotropic activity ; serum ; early pregnancy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In an attempt to track the proliferation/demise of trophoblastic tissues in women following gamete transfer (GT) or in vitro fertilization/embryo transfer (IVF/ET), we have measured levels of human chorionic gonadotropin (hCG) in serum of 180 patients on days 7 and 14 following oocyte pickup (OPU). Serum hCG levels were measured by immunoassay and by a bioassay based on the capacity of the sample to stimulate testosterone secretion by cultured mouse Leydig cells. Based on determinations of bioactive and immunoactive hCG in serum from 18 of 180 patients who subsequently delivered (12 of 73 GT, 6 of 107 IVF/ET;P〈0.05) and classification of patients in accord with their compliance or noncompliance with these ranges of values, about 70% of all patients in the present study were classified as “pregnant” 7 days following OPU. Based on these same criteria, about 23% were pregnant 7 days later. Biochemical pregnancy rates on days 7 and 14 following GT (near 73 and 27%, respectively) were not different from the respective values following IVF/ET (near 68 and 20%, respectively:P〉0.05). The luteotropin bioassay described is highly sensitive to hCG (to 0.02 mIU/ml serum) and appears appropriate to the characterization of proliferation/demise of embryonic tissues during the 14 days after gamete/embryo transfer. In addition, through its representation of the cumulative luteotropic properties of human serum and its insensitivity to biologically inactive hCG subunits; this bioassay appears more appropriate than hCG immunoassay in the monitoring of early embryonic signalling following assisted (or spontaneous) conception in the woman.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 38 (1994), S. 142-147 
    ISSN: 1040-452X
    Keywords: Micromanipulation ; Zona pellucida ; DNA repair ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The treatment of male factor-related infertility has been approached with the advent of several methods for microsurgical fertilization, such as the partial dissection of the zona pellucida (PZD) and the injection of sperm into the perivitelline space (PVSI) of oocytes. These techniques are designed to increase sperm-oolemma interaction by circumventing passage of the sperm through the zona pellucida. The present study was performed to evaluate the influence of PZD and PVSI on the in vitro development of mouse embryos by assessing the rate of sister chromatid exchange (SCE). SCE is considered to be a sensitive indirect indicator of DNA lesions due to various conditions. Oocytes were cultured in vitro after PZD or PVSI and then examined for SCE. There was no significant difference in SCE between control and treatment groups of embryos and the values were similar to those reported by Saito et al. (Fertil Steril 41:460-464, 1984). The rate of SCE was low during the first two mitotic cycles, then increased from cycle two to three before declining slightly between the 3rd and 4th cycles of cell division. These data demonstrate that the direct interaction of sperm and oocyte by PZD or PVSI did not have an adverse effect on the development of mouse embryos as assessed by the rate of SCE. © 1994 Wiley-Liss, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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