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1.
Preimplantation genetic diagnosis is a preventive approach for identifying genetic abnormalities in early stages of reproduction. We used preimplantation genetic aneuploidy screening in 230 cycles of patients with indications of advanced maternal age, recurrent implantation failure, recurrent spontaneous abortions, or severe male factor. Biopsied blastomeres from embryos with six to eight blastomeres on day 3 were fixed and fluorescence in situ hybridization was utilized on chromosomes 13, 16, 18, 21, 22, X, and Y. Among 945 morphologically normal embryos, 314 were diagnosed as chromosomally normal. Trisomy and monosomy were observed in 36% of the cases (18% each). Embryo transfer was used in 144 cycles, resulting in 41 pregnancies. Thirty-seven healthy babies were delivered, with a take-home baby rate of 24.2% and an implantation rate of 22%. We recommend preimplantation genetic aneuploidy screening as a valuable technique to select normal chromosome embryos in order to avoid multiple pregnancies due to the multiple embryo transfers that are normally necessary to ensure pregnancy in poor prognosis in vitro fertilization patients.  相似文献   

2.
F I Chasalow  S L Blethen 《Steroids》1985,45(2):187-193
Antibodies to dehydroepiandrosterone (DHEA) can be generated by coupling DHEA to carrier proteins. This report describes the use of antibodies to three different DHEA-protein complexes for the measurement of DHEA in serum and cord plasma. Each of the three antibodies produces an assay with equivalent results in serum from adults and older children. However, with cord plasma samples, two of the antibodies detected much more cross-reacting material than was detected with the third antibody. In order to determine the basis for this discrepancy, a pool of cord plasma was extracted in a manner similar to that used in the assay procedure. The steroids in the extract were separated by chromatography on a Sephadex LH-20 column and individual fractions were assayed for DHEA with each of the antibodies. There were several peaks of cross-reacting material present in cord blood that were not present in comparable amounts in serum from adults. These results indicate that assays for DHEA need to be separately validated with samples from adults and from infants.  相似文献   

3.

Background

Exposure of pregnant mothers to elevated concentrations of circulating testosterone levels is associated with fetal growth restriction and delivery of small-for-gestational-age babies. We examined whether maternal testosterone crosses the placenta to directly suppress fetal growth or if it modifies placental function to reduce the capacity for transport of nutrients to the fetus.

Methods

Pregnant rats were exposed to testosterone propionate (TP; 0.5 mg/kg) by daily subcutaneous injection from gestational days (GD) 15-19. Maternal and fetal testosterone levels, placental nutrient transport activity and expression of transporters and birth weight of pups and their anogenital distances were determined.

Results

This dose of TP doubled maternal testosterone levels but had no effect on fetal testosterone levels. Maternal daily weight gain was significantly lower only on GD 19 in TP treated dams compared to controls. Placental weight and birth weight of pups were significantly reduced, but the anogenital distance of pups were unaffected by TP treatment. Maternal plasma amino acids concentrations were altered following testosterone exposure, with decreases in glutamine, glycine, tyrosine, serine, proline, and hydroxyproline and increases in asparagine, isoleucine, leucine, lysine, histidine and arginine. In the TP dams, placental system A amino acid transport activity was significantly reduced while placental glucose transport capacity was unaffected. Decreased expression of mRNA and protein levels of slc38a2/Snat2, an amino acid transporter, suggests that reduced transporter proteins may be responsible for the decrease in amino acid transport activity.

Conclusions

Taken together, these data suggest that increased maternal testosterone concentrations do not cross the placenta to directly suppress fetal growth but affects amino acid nutrient delivery to the fetus by downregulating specific amino acid transporter activity.  相似文献   

4.
In this study we investigated whether or not liver regeneration is facilitated by dehydroepiandrosterone (DHEA) after partial (70%) hepatectomy in rats. Treatment with DHEA (300 mg/kg body weight) did not cause any significant increase in the expression ratio of proliferating cell nuclear antigen (PCNA) in sham-operated controls; however, in partially hepatectomized rats it caused a significant increase in the ratio in hepatocytes 24 and 36 hr after hepatectomy. In partially hepatectomized rats, DHEA treatment significantly accelerated the restoration of liver 48, 60, and 72 hr after partial hepatectomy. The restoration rate in DHEA-treated hepatectomized rats at 72 hr was 1.3-fold greater than in partially hepatectomized controls. Treatment with androstenedione (300 mg/kg body weight), the first metabolite of DHEA, did not cause any significant increase in the expression of PCNA in either sham-operated controls or partially hepatectomized rats. These results indicate that DHEA itself promotes the liver regenerative process after partial hepatectomy in rats.  相似文献   

5.
We examined the effect of dehydroepiandrosterone (DHEA) on glucose uptake and phospholipase D (PLD) activation in rat adipocytes. DHEA (1 microM) provoked a twofold increase in [3H]2-deoxyglucose (DG) uptake for 30 min. Incorporation of [3H]glycerol into diacylglycerol was increased 150% above basal level for 20 min after stimulation with 1 microM DHEA. DHEA increased PLD activity, measured by the incorporation into [3H]phosphatidylethanol in [3H]palmitate labelled rat adipocytes, or by [3H]choline release in [methyl-(3)H]choline labeled rat adipocytes. Our results suggest that DHEA stimulates glucose uptake with activation of PLD in rat adipocytes.  相似文献   

6.
J F Garcia 《Theriogenology》2001,56(9):1393-1399
In the past years, research in embryo technologies is moving to the establishment of preimplantation genetic typing or also denominated preimplantation genetic diagnosis (PGD). The objectives of these tests are the prevention of genetic diseases transmission and the prediction of phenotypic characteristics, as well as sex determination, genetic disorders and productive and reproductive profiles, prior to the embryo transfer or freezing, during early stages of development. This paper points out the state-of-the-art of PGD, mainly in cattle and discuss the perspectives of multiloci genetic analysis of embryos.  相似文献   

7.
BACKGROUND: Dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEAS) are the major steroid hormones secreted by the adrenal gland. Administration of DHEA has been reported to have beneficial effects on aging, diabetes, and atherosclerosis. Apoptosis is a normal physiologic process that occurs during embryonic development as well as in the maintenance of tissue homeostasis. In this study, we examined the suppressive effect of DHEA(S) on staurosporine-induced apoptosis in human peripheral blood lymphocytes (PBL). METHODS: Apoptosis was induced in human PBL with staurosporine and measured by flow cytometry utilizing Annexin V and propidium iodide (PI) staining. The quantity of FITC+/PI- cells corresponded to early apoptosis, while that of FITC+/PI+ cells corresponded to late apoptosis or secondary necrosis. RESULTS: The fraction of staurosporine-induced early apoptosis but not that of secondary necrosis in PBL was reduced by the treatment with either DHEA or DHEAS. Furthermore, this apoptosis was neither associated with androgen receptor (AR) nor with estrogen receptor (ER). CONCLUSIONS: This is the first study showing that DHEA(S) inhibits apoptosis in human PBL through a mechanism independent of either ARs or ERs. DHEA(S) may be a promising chemopreventive drug for aging, diabetes, and atherosclerosis.  相似文献   

8.
Preimplantation genetic screening (PGS) is a component of IVF entailing selection of an embryo for transfer on the basis of chromosomal normalcy. If PGS were integrated with single embryo transfer (SET) in a surrogacy setting, this approach could improve pregnancy rates, minimize miscarriage risk, and limit multiple gestations. Even without PGS, pregnancy rates for IVF surrogacy cases are generally satisfactory, especially when treatment utilizes embryos derived from young oocytes and transferred to a healthy surrogate. However, there could be a more general role for PGS in surrogacy, since background aneuploidy in embryos remains a major factor driving implantation failure and miscarriage for all infertility patients. At present, the proportion of IVF cases involving GS is limited, while the number of IVF patients requesting PGS appears to be increasing. In this report, the relevance of PGS for surrogacy in the rapidly changing field of assisted fertility medicine is discussed. Birth Defects Research (Part C) 108:98–102, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   

9.
The effect of theophylline on poly(ADP-ribosyl)ation was investigated. The poly(ADP-ribose) synthetase activity in vitro was markedly reduced in the liver nuclei prepared from theophylline-treated chick embryo. This reduction was not due to the enzyme inhibition by theophylline contamination in the nuclear fraction. The hydroxyapatite column chromatographic analysis of [3H]adenosine-labelled poly(ADP-ribose)molecules formed in vivo revealed that the in vivo formation of poly(ADP-ribose)molecules was also decreased by theophylline administration. The theophylline-induced reduction of poly(ADP-ribose) synthesis was not due to either low NAD levels or to a decrease in the chain length of the poly(ADP-ribose) molecule, rather this reduction was derived from a decrease in the number of poly(ADP-ribose) molecule. Possible mechanisms related to reduction of poly(ADP-ribose) synthesis in vivo are discussed.  相似文献   

10.
The effect of theophylline on poly(ADP-ribosyl)ation was investigated. The poly(ADP-ribose) synthetase activity in vitro was markedly reduced in the liver nuclei prepared from theophylline-treated chick embryo. This reduction was not due to the enzyme inhibition by theophylline contamination in the nuclear fraction. The hydroxyapatite column chromatographic analysis of [3H]adenosine-labelled poly(ADP-ribose) molecules formed in vivo revealed that the in vivo formation of poly(ADP-ribose) molecules was also decreased by theophylline administration. The theophylline-induced reduction of poly(ADP-ribose) synthesis was not due to either low NAD levels or to a decrease in the chain length of the poly(ADP-ribose) molecule, rather this reduction was derived from a decrease in the number of poly(ADP-ribose) molecules. Possible mechanisms related to reduction of poly(ADP-ribose) synthesis in vivo are discussed.  相似文献   

11.
Dehydroepiandrosterone (DHEA) is important for human health, especially for women. All estrogens and practically half of androgens are synthesized from DHEA in peripheral tissues. However, the mechanism and exact target tissues of DHEA biotransformation in the female are not fully clear. The present study showed that maximal content of androstenedione (AD) and testosterone (T) were observed at 3h after DHEA administration in female rats, which was 264% and 8000% above the control, respectively. Estradiol (E2) content significantly increased at 6h after DHEA administration, which was 113% higher than that in control group. Gavage with DHEA could significantly reduce 3β-hydroxysteroid dehydrogenase (3β-HSD) mRNA level at 3-12h and 17β-hydroxysteroid dehydrogenase (17β-HSD) mRNA level at 12h in ovary, while increasing aromatase mRNA levels at 6, 24, and 48h. It is interesting that administration of DHEA caused a significant increase of 17β-HSD, 3β-HSD and aromatase mRNA levels in adrenal. The AD and T contents also markedly increased by 537% and 2737% after DHEA administration in ovariectomised rats, in company with a significant increase in 17β-HSD and 3β-HSD mRNA levels and decreased aromatase mRNA level in adrenal. However, DHEA administration did not restore the decreased E2, estrone (E1), and progesterone (P) caused by the removal of the ovaries in females. These results clearly illustrated that exogenous DHEA is preferentially converted into androgens in adrenal, while its conversion to estrogens mainly happens in the ovary through steroidogenic enzyme in female rats.  相似文献   

12.
Previous studies have demonstrated concentrating neuroendocrinological disturbances in chronic fatigue syndrome (CFS) patients, concentrating in particular on low cortisol levels and a hypothalamic deficiency. In order to investigate the dynamic response of the adrenal glands, we measured dehydroepiandrosterone (DHEA) in serum after adreno-corticotropic hormone (ACTH) stimulation during 60 minutes in 22 CFS-patients and 14 healthy controls. We found normal basal DHEA levels, but a blunted serum DHEA response curve to i.v. ACTH injection. This observation adds to the large amount of evidence of endocrinological abnormalities in CFS. Relative glucocorticoid deficiency might contribute to the overall clinical picture in CFS, and could explain some of the immunological disturbances observed in this syndrome.  相似文献   

13.
Studies to elucidate the role of dehydroepiandrosterone (DHEA) metabolism in neuroprotection have compared its relative 7-hydroxylation against estrogen formation by way of 4-androstenedione (AD) in various rodent brain cell lines. In all cases, the 7alpha- and 7beta-hydroxy epimers of DHEA were found to be the dominant products with one notable exception. BV2 mouse microglia were virtually unable to hydroxylate DHEA at C-7 and converted AD to a major unknown metabolite not observed with mouse BHc hippocampal cells. In this paper, we describe the identification of this compound based on its physical properties and analysis by TLC and HPLC. Its identity as 3beta-hydroxy-4-androstene-17-one, the Delta(4)-isomer of DHEA, was confirmed by mass spectrometry (LC/MS), as well as by reverse isotope dilution analysis involving co-crystallization with the synthetic steroid. Possible mechanisms for the formation of this isomer of DHEA by BV2 microglia are proposed, together with that of other C-19 steroids detected which include testosterone (T), 5alpha-dihydrotestosterone and 5alpha-androstanedione.  相似文献   

14.
We have recently taken advantage of the unique power of DNA microarrays to compare the genomic expression profile of tetrahydrogestrinone (THG) with that of dihydrotestosterone (DHT), the most potent natural androgen, thus clearly demonstrating that THG is an anabolic steroid. In 2004, the U.S. Controlled Substances Act has been modified to include androstenedione (4-dione) as an anabolic steroid. However, despite the common knowledge that dehydroepiandrosterone (DHEA) is the precursor of testosterone, DHEA has been excluded from the list of anabolic steroids. We thus used the same DNA microarray technology to analyze the expression profile of practically all the 30,000 genes of the mouse genome modulated by DHEA and DHT in classical androgen-sensitive tissues. Daily subcutaneous injections of DHT (0.1mg) or DHEA (3mg) for 1 month in gonadectomized C57BL6/129 SV mice increased ventral prostate, dorsal prostate, seminal vesicle and preputial gland weight (p<0.01 for all tissues). As early as 24h after single injection of the two steroids, 878, 2681 and 14 probe sets were commonly stimulated or inhibited (p<0.01, change> or =30%), in the prostate (ventral+dorsal), seminal vesicles and preputial glands, respectively, compared to tissues from gonadectomized control animals. After 7 days of daily treatment with DHEA and DHT, 629, 919 and 562 probe sets were commonly modulated in the same tissues while after 27 days of treatment, 1195, 5127 and 2883 probe sets were modulated, respectively. In analogy with the data obtained with THG, the present microarray data provide an extremely precise and unquestionable genomic signature and proof of the androgenic/anabolic activity of DHEA. Such data add to the literature showing that DHEA is transformed into androgens in the human peripheral tissues as well as in laboratory animal species, including the monkey, thus exerting potent androgenic/anabolic activity. The present microarray approach to identify anabolic compounds is applicable to all potential androgenic/anabolic compounds.  相似文献   

15.
In this study, we focused on the derivation of human embryonic stem cell (hESC) from preimplantation genetic screening (PGS)-analyzed and preimplantation genetic diagnosis (PGD)-analyzed embryos. Out of 62 fresh PGD/PGS-analyzed embryos, 22 embryos reached the blastocyst stage. From 12 outgrowth blastocysts, we derived four hESC lines onto a feeder layer. Surprisingly, karyotype analysis showed that hESC lines derived from aneuploid embryos had diploid female karyotype. One hESC line was found to carry a balanced Robertsonian translocation. All the cell lines showed hESC markers and had the pluripotent ability to differentiate into derivatives of the three embryonic germ layers. The established lines had clonal propagation with 22–31% efficiency in the presence of ROCK inhibitor. These results further indicate that hESC lines can be derived from PGD/PGS-analyzed embryos that are destined to be discarded and can serve as an alternative source for normal euploid lines.  相似文献   

16.
In many species, male territorial aggression is tightly coupled with gonadal secretion of testosterone (T). In contrast, in song sparrows (Melospiza melodia morphna), males are highly aggressive during the breeding (spring) and nonbreeding (autumn and early winter) seasons, but not during molt (late summer). In aggressive nonbreeding song sparrows, plasma T levels are basal (< or = 0.10 ng/ml), and castration has no effect on aggression. However, aromatase inhibitors reduce nonbreeding aggression, indicating a role for estrogen in wintering males. In the nonbreeding season, the substrate for brain aromatase is unclear, because plasma T and androstenedione levels are basal. Aromatizable androgen may be derived from plasma dehydroepiandrosterone (DHEA), an androgen precursor. DHEA circulates at elevated levels in wintering males (approximately 0.8 ng/ml) and might be locally converted to T in the brain. Moreover, plasma DHEA is reduced during molt, as is aggression. Here, we experimentally increased DHEA in wild nonbreeding male song sparrows and examined territorial behaviors (e.g., singing) and discrete neural regions controlling the production of song. A physiological dose of DHEA for 15 days increased singing in response to simulated territorial intrusions. In addition, DHEA treatment increased the volume of a telencephalic brain region (the HVc) controlling song, indicating that DHEA can have large-scale neuroanatomical effects in adult animals. The DHEA treatment also caused a slight increase in plasma T. Exogenous DHEA may have been metabolized to sex steroids within the brain to exert these behavioral and neural effects, and it is also possible that peripheral metabolism contributed to these effects. These are the first results to suggest that exogenous DHEA increases male-male aggression and the size of an entire brain region in adults. The data are consistent with the hypothesis that DHEA regulates territorial behavior, especially in the nonbreeding season, when plasma T is basal.  相似文献   

17.
We compared two methods of zona pellucida drilling. 213 embryos were biopsied with acid Tyrode. Each biopsy took 3 minutes and the entire procedure ~29 minutes. 5% of blastomeres lysed, 49% of embryos became blastocyst and 36% of patients became pregnant. 229 embryos were biopsied with laser. Each biopsy took 30 seconds and the entire procedure ~7 minutes. 2.5% of blastomeres lysed, 50.6% of embryos became blastocyst and 47% of patients became pregnant. We can conclude that laser can be used for embryo biopsy. Reduction of embryo exposure and of removed blastomeres is associated with increased blastocysts available for transfer and a better clinical outcome.  相似文献   

18.
Investigations were conducted to quantitate polyadenylic acid and estimate the synthesis of polyadenylated RNA in mouse embryos at several stages of preimplantation development. Poly(A) was assayed by molecular hybridization of total embryonic RNA with [3H]polyuridylic acid. The mean values of poly(A) in the ovulated oocytes and in the one-cell, two-cell, and blastocyst stages of the embryo were 1.9, 1.6, 0.68, and 3.8 pg, respectively. Synthesis of polyadenylated RNA was estimated by affinity chromatography of [3H]uridine-labeled embryo RNA on oligo(dT)-cellulose. The proportions of newly synthesized RNA bound by oligo(dT)-cellulose at the 2-cell, 8- to 16-cell, and blastocyst stages were 6.7, 3.5, and 3.3%, respectively. These results suggest that significant quantities of maternal mRNA are present during early development of the mouse, but that polyadenylation of RNA transcribed from the embryonic genome occurs as early as the two-cell stage.  相似文献   

19.
20.
We conducted an isozyme study in 22 populations of five Pleurothallis (Orchidaceae) species (12 loci in nine enzymatic systems). The genetic variability in all populations is surprisingly high (P = 58-83%, A = 2.1-3.8, H(e) = 0.25-0.43) in spite of the fact that the five species are pollinated by small flies whose behavior enables self-pollination. We suggest that self-incompatibility, inbreeding depression, and mechanical barriers that prevent self-pollination in these species are responsible for the maintainance of the high genetic variability. These traits are uncommon in Orchidaceae, but have been observed in these and some other species pollinated by flies or other pollinators with behavior that facilitates self-pollination. The genetic similarity among conspecific populations is also high for species with very short-range flying pollinators. Only one population of P. teres presented values of genetic similarity lower than usually observed in allopatric conspecific populations. Morphology, however, does not support its segregation as a new taxon. All species can be recognized by their enzymatic patterns, and the results agree with recently proposed taxonomic realignments. Conversely, the supposed affinities among these species based on floral morphology are not supported, and we hypothesize that it may be due to convergence in species with similar pollinators.  相似文献   

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