129 resultados para EMBRYO CRYOPRESERVATION

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


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Objective: To compare cryopreservation of mature human oocytes with slow-rate freezing and vitrification and determine which is most efficient at establishing a pregnancy. Design: Prospective randomized. Setting: Academically affiliated, private fertility center. Patient(s): Consenting patients with concerns about embryo cryopreservation and more than nine mature oocytes at retrieval were randomized to slow-rate freezing or vitrification of supernumerary (more than nine) oocytes. Intervention(s): Oocytes were frozen or vitrified, and upon request oocytes were thawed or warmed, respectively. Main Outcome Measure(s): Oocyte survival, fertilization, embryo development, and clinical pregnancy. Result(s): Patient use has resulted in 30 thaws and 48 warmings. Women`s age at time of cryopreservation was similar. Oocyte survival was significantly higher following vitrification/warming (81%) compared with freezing/thawing (67%). Fertilization was more successful in oocytes vitrified/warmed compared with frozen/thawed. Fertilized oocytes from vitrification/warming had significantly better cleavage rates (84%) compared with freezing/thawing (71%) and resulted in embryos with significantly better morphology. Although similar numbers of embryos were transferred, embryos resulting from vitrified oocytes had significantly enhanced clinical (38%) pregnancy rates compared with embryos resulting from frozen oocyte (13%). Miscarriage and/or spontaneous abortion rates were similar. Conclusion(s): Our results suggest that vitrification/warming is currently the most efficient means of oocyte cryopreservation in relation to subsequent success in establishing pregnancy. (Fertil Steril (R) 2010; 94: 2088-95. (C) 2010 by American Society for Reproductive Medicine.)

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To review and discuss the pathophysiology and prevention strategies for ovarian hyperstimulation syndrome (OHSS), which is a condition that may occur in up to 20% of the high risk women submitted to assisted reproductive technology cycles. The English language literature on these topics were reviewed through PubMed and discussed with emphasis on recent data. The role of estradiol, luteinizing hormone, human chorionic gonadotropin (hCG), inflammatory mediators, the renin-angiotensin system and vascular endothelial growth factor is discussed in the pathophysiology of OHSS. In addition we consider the prevention strategies, including coasting, administration of albumin, renin-angiotensin system blockage, dopamine agonist administration, non-steroidal anti-inflammatory administration, GnRH antagonist protocols, reducing hCG dosage, replacement of hCG and in vitro maturation of oocytes (IVM). Among the many prevention strategies that have been discussed, the current evidence points to the replacement of hCG by GnRH agonists in antagonist cycles and the performance of IVM procedures as the safest approaches.

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BACKGROUND: Comparative genomic hybridization (CGH) is a valuable alternative to fluorescence in situ hybridization (FISH) for preimplantation genetic screening (PGS) because it allows full karyotype analysis. However, this approach requires the cryopreservation of biopsied embryos until results are available. The aim of this study is to reduce the hybridization period of CGH, in order to make this short-CGH technique suitable for PGS of Day-3 embryos, avoiding the cryopreservation step. METHODS: Thirty-two fibroblasts from six aneuploid cell lines (Coriell) and 48 blastomeres from 10 Day-4 embryos, discarded after PGS by FISH with 9 probes (9-chr-FISH), were analysed by short-CGH. A reanalysis by the standard 72 h-CGH and FISH using telomeric probes was performed when no concordant results between short-CGH and FISH diagnosis were observed. The short-CGH was subsequently applied in a clinical case of advanced maternal age. RESULTS: In 100% of the fibroblasts analysed, the characteristic aneuploidies of each cell line were detected by short-CGH. The results of the 48 blastomeres screened by short-CGH were supported by both 72 h-CGH results and FISH reanalysis. The chromosomes most frequently involved in aneuploidy were 22 and 16, but aneuploidies for the other chromosomes, excepting 1, 10 and 13, were also detected. Forty-one of the 94 aneuploid events observed (43.6%) corresponded to chromosomes which are not analysed by 9-chr-FISH. CONCLUSIONS: We have performed a preliminary validation of the short-CGH technique, including one clinical case, suggesting this approach may be applied to Day-3 aneuploidy analysis, thereby avoiding embryo cryopreservation and perhaps helping to improve implantation rate after PGS.

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Methods used for lipid analysis in embryos and oocytes usually involve selective lipid extraction from a pool of many samples followed by chemical manipulation, separation and characterization of individual components by chromatographic techniques. Herein we report direct analysis by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of single and intact embryos or oocytes from various species. Biological samples were simply moisturized with the matrix solution and characteristic lipid ( represented by phosphatidylcholines, sphingomyelins and triacylglycerols) profiles were obtained via MALDI-MS. As representative examples, human, bovine, sheep and fish oocytes, as well as bovine and insect embryos were analyzed. MALDI-MS is shown to be capable of providing characteristic lipid profiles of gametes and embryos and also to respond to modifications due to developmental stages and in vitro culture conditions of bovine embryos. Investigation in developmental biology of the biological roles of structural and reserve lipids in embryos and oocytes should therefore benefit from these rapid MALDI-MS profiles from single and intact species.-Ferreira, C. R., S. A. Saraiva, R. R. Catharino, J. S. Garcia, F. C. Gozzo, G. B. Sanvido, L. F. A. Santos, E. G. Lo Turco, J. H. F. Pontes, A. C. Basso, R. P. Bertolla, R. Sartori, M. M. Guardieiro, F. Perecin, F. V. Meirelles, J. R. Sangalli, and M. N. Eberlin. Single embryo and oocyte lipid fingerprinting by mass spectrometry. J. Lipid Res. 2010. 51: 1218-1227.

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Melatonin (MEL) acts as a powerful scavenger of free radicals and direct gonadal responses to melatonin have been reported in the literature. Few studies, however, have evaluated the effect of MEL during in vitro maturation (IVM) on bovine embryos. This study tested the addition of MEL to maturation medium (MM) with no gonadotropins on nuclear maturation and embryo development rates and the incidence of DNA damage in resulting embryos. Cumulus-oocyte complexes were aspirated from abattoir ovaries and cultured in MM (TCM-199 medium supplemented with 10% fetal calf serum - FCS) at 39ºC and 5% CO2 in air. After 24 hours of culture in MM with 0.5 µg mL-1 FSH and 5.0 µg mL-1 LH; 10-9 M MEL) or 10-9 M MEL, 0.5 µg mL-1 FSH and 5.0 µg mL-1 LH, the oocytes were stained with Hoechst 33342 to evaluate nuclear maturation rate. After in vitro fertilization and embryo culture, development rates were evaluated and the blastocysts were assessed for DNA damage by Comet assay. There was no effect of melatonin added to the MM, alone or in combination with gonadotropins, on nuclear maturation, cleavage and blastocyst rates. These rates ranged between 88% to 90%, 85% to 88% and 42% to 46%, respectively. The extent of DNA damage in embryos was also not affected by MEL supplementation during IVM. The addition of 10-9 M MEL to the MM failed to improve nuclear maturation and embryo development rates and the incidence of DNA damage in resulting embryos, but was able to properly substitute for gonadotropins during IVM.

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Background: The establishment of an in vitro production (IVP) of embryo in swine allows the generation of embryos with the same quality as in vivo produced embryos with less costs and time. In order to achieve successful fertilization under normal circumstances in vivo, mammalian spermatozoa must first undergo capacitation and then acrosome reaction. The purpose of this study was compared the efficacious of IP/CFDA fluorescence and Coomassie Blue G (CB) staining to detect capacitated sperm cells in refrigerated and fresh semen. Morever, it was investigated the efficacious of caffeine and chondroitin sulphate to promote in vitro sperm capacitation and in vitro embryo produced (IVP) of swine embryos. Materials, Methods & Results: A sperm-rich fraction from ejaculate was obtained using the gloved-hand method and the gel-free fraction was separated using sterile gauze. The semen was diluted in BTS at a final concentration of 1.5 x 10(8) cells/mL. The sperm suspension was incubated for 2 h at 25 degrees C, refrigerated and maintained for 1 h at 15-18 degrees C (refrigerated group) or used immediately (fresh group). Sperm capacitation was assessed by IP/CFDA fluorescence and CB staining for both fresh and refrigerated semen. For PI/CFDA evaluation, a final solution containing 1.7 mM formaldehyde, 7.3 mM PI and 20 mM CFDA in 950 mu L saline was prepared. In the dark, 40 mu L PI/CFDA final solution was added to 10 mu L semen and after 8 min, slides were analyzed on epifluorescence microscopy. For CB evaluation, sperm cells were fixed in 4% paraformaldehyde for 10 min and centrifuged twice at 320 x g in ammonium acetate pH 9 for 8 min. A smear was made and stained with 2.75 mg/mL CB in solution containing 12.5% methanol, 25% glacial acetic acid and 62.5% water, for 2 min. The smear was washed in running water, air dried and sealed with Permount (R), diluted 2:1 in xilol to avoid staining oxidation. Our results showed that refrigeration did not affect sperm capacitation and comparing staining methods, the PI/CFDA combination was more efficient to detect capacitated sperm, when compared to CB staining. In experiment 2, we evaluated the effect of different incubation time (1 - 5 h) with chondroitin sulfate and caffeine on sperm capacitation. For in vitro fertilization, oocytes were obtained from slaughterhouse ovaries. Oocytes with a thick and intact cumulus oophurus layer and cytoplasm with homogenous granules were selected for in vitro maturation for 44 h. According to the results of experiment 2, it was used for in vitro fertilization refrigerated semen was capacitated with 50 mu g/mL chondroitin sulfate for 2 h or capacitated with 5 mu g/mL caffeine for 3 h. Six hours after insemination, cumulus oophorus cells were mechanically removed and oocytes were washed and incubated in microdrops of culture medium. Embryo development after fertilization with sperm capacitated with caffeine or chondroitin sulfate was evaluated on days 3, 5 and 7 of culture. No differences were observed in days 3 or 5 of in vitro culture. However, it was observed an increase on blastocyst rate on Day 7 of culture when caffeine was used as the capacitor agent. Discussion: Molecular basis of sperm capacitation is still poor understood. Sperm capacitation can occur in vitro spontaneously in defined media without addition of biological fluids. We observed that sperm capacitation increased as incubation period enlarged and it was observed using Coomassie blue G and PI/CFDA for fresh semen and for refrigerated semen. It can be concluded that the cooling of semen did not change their pattern of sperm capacitation and this is best assessed by IP/CFDA than by CB. In addition to the use of caffeine in sperm capacitation produces more blastocysts than the chondroitin sulfate after in vitro fertilization.

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The objective was to determine whether aging of sperm caused by incubation at normothermic (38.5 C) or heat shock (40 C) temperatures for 4 h prior to oocyte insemination affects sperm motility, fertilizing ability, competence of the resultant embryo to develop to the blastocyst stage and blastocyst sex ratio. In the first experiment, the percent of sperm that were motile was reduced by aging (P<0.001) and the reduction in motility was greater for sperm at 40 C compared to sperm at 38.5 C (P<0.01). In the second experiment, oocytes were inseminated with aged sperm. A smaller percent of oocytes fertilized with sperm aged at either temperature cleaved by Day 3 after insemination than oocytes fertilized with fresh sperm (P<0.05). There was no effect of sperm aging on the percent of oocytes or cleaved embryos that developed to the blastocyst stage. Aging of sperm before fertilization at 38.5 C reduced the percent of blastocysts that were male (P=0.08). In the third experiment, incubation of sperm at 38.5 C or 40 C for 4 h did not reduce fertilizing ability of sperm as determined by pronuclear formation at 18 h post insemination. In conclusion, aging of sperm reduced cleavage rate and the percent of blastocysts that were males but had no effect on the developmental capacity of the. embryo. The effect of aging on cleavage rate may represent reduced motility and errors occurring after fertilization and pronuclear formation. Aging at a temperature characteristic of maternal hyperthermia had little additional effect except that polyspermy was reduced. Results indicate that embryo competence for development to the blastocyst stage is independent of sperm damage as a result of aging for 4 h at normothermic or hyperthermic temperatures.

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Aiming to achieve the ideal time of ovum pick-up (OPU) for in vitro embryo production (IVP) in crossbred heifers, two Latin square design studies investigated the effect of ovarian follicular wave synchronization with estradiol benzoate (EB) and progestins. For each experiment, crossbred heifers stage of estrous cycle was synchronized either with a norgestomet ear implant (Experiment 1) or a progesterone intravaginal device (Experiment 2) for 7d, followed by the administration of 150 mu g D-cloprostenol. On Day 7, all follicles >3 mm in diameter were aspirated and implants/devices were replaced by new ones. Afterwards, implant/device replacement was conducted every 14 d. Each experiment had three treatment groups. In Experiment I (n = 12), heifers in Group 2X had their follicles aspirated twice a week and those in Groups 1X and 1X-EB were submitted to OPU once a week for a period of 28 d. Heifers from Group 1X-EB also received 2 mg EB i.m. immediately after each OPU session. In Experiment 2 (n = 11), animals from Group 0EB did not receive EB while heifers in Groups 2EB and 5EB received 2 and 5 mg of EB respectively, immediately after OPU. The OPU sessions were performed once weekly for 28 d. Therefore, in both experiments, four OPU sessions were performed in heifers aspirated once a week and in Experiment 1, eight OPU sessions were done in heifers aspirated twice a week. Additionally, during the 7-d period following follicular aspiration, ovarian ultrasonography examinations were conducted to measure diameter of the largest follicle and blood samples were collected for FSH quantification by RIA. In Experiment 1, all viable oocytes recovered were in vitro matured and fertilized. Results indicated that while progestin and EB altered follicular wave patterns, this treatment did not prevent establishment of follicular dominance on the ovaries of heifers during OPU at 7-d intervals. Furthermore, the proposed stage of follicular wave synchronization strategies did not improve the number and quality of the recovered oocytes, or the number of in vitro produced embryos. (C) 2009 Elsevier B.V. All rights reserved.

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Data on fertilisation and embryo quality in dairy cattle are presented and the main factors responsible for the low fertility of single-ovulating lactating cows and embryo yield in superovulated dairy cattle are highlighted. During the past 50 years, the fertility in high-producing lactating dairy cattle has decreased as milk production increased. Recent data show conception rates to first service to be approximately 32% in lactating cows, whereas in heifers it has remained above 50%. Fertilisation does not seem to be the principal factor responsible for the low fertility in single-ovulating cows, because it has remained above 80%. Conversely, early embryonic development is impaired in high-producing dairy cows, as observed by most embryonic losses occurring during the first week after fertilisation. However, in superovulated dairy cattle, although fertilisation failure is more pronounced, averaging approximately 45%, the percentage of fertilised embryos viable at 1 week is quite high (>70%). Among the multifactorial causes of low fertility in lactating dairy cows, high feed intake associated with low concentrations of circulating steroids may contribute substantially to reduced embryo quality. Fertilisation failure in superovulated cattle may be a consequence of inappropriate gamete transport due to hormonal imbalances.

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Cryopreservation of parathyroid tissue is used in the surgical treatment of secondary hyperparathyroidism. After surgical resection, the tissue is temporarily maintained in a cell culture solution until it arrives at the specialized laboratory where the cryopreservation process will take place. The present study evaluates the time that the human hyperplastic parathyroid gland tissue can wait before cryopreservation, based on parathyroid cell ultrastructural integrity. This prospective study included 11 patients who underwent total parathyroidectomy with heterotopic autotransplantation and cryopreservation of parathyroid tissue fragments. Part of the tissue was kept in cell culture solution at 4A degrees C. Five time periods between 2 and 24 h were defined, and parathyroid fragments were kept in the solution for that length of time. At the end of each period, the fragments were removed from the transport solution, fixed, and prepared for ultrathin sections. Of the 11 cases studied, 10 showed ultrastructural findings consistent with cellular viability in tissue fragments that remained in the transport solution up to 12 h. Electron microscopy revealed that cell adhesion and the integrity of plasma membranes, nuclei, and mitochondria were preserved in one case for up to 24 h. Changes in mitochondrial structure represented the most constant ultrastructural damage seen in the cases studied, in addition to the presence of edema and cell vacuoles. Analysis of the ultrastructure of hyperplastic parathyroid gland tissue showed that ultrastructural integrity was in most cases properly maintained in fragments stored up to 12 h in a cell culture solution at 4A degrees C.

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INTRODUCTION The management of nonpalpable testicular masses is a challenging task, and coexisting infertility can further complicate the treatment decisions. We present our technique for microsurgical organ-sparing resection of incidental nonpalpable testicular nodules combined with microdissection for testicular sperm extraction and tissue cryopreservation in azoospermic patients. TECHNICAL CONSIDERATIONS Five infertile patients with azoospermia presented with nonpalpable hypoechoic testicular masses that were detected by Ultrasonography and underwent organ-sparing surgery. The testis was delivered through an inguinal incision, and the blood circulation was interrupted with a vascular clamp placed on the spermatic cord. Sludged ice was used to prevent warm ischemia, and a temperature probe was used to control the temperature at 12 degrees-15 degrees C. Real-time reflex ultrasonography was used to locate the tumor, and a stereotaxic hook-shaped needle was inserted under ultrasound guidance. The needle was placed adjacent to the tumor to guide the microsurgical resection. The tunica albuginea was incised over the tumor, which was dissected and removed, along with the adjoining parenchymal tissue. Frozen section studies were performed and, if malignancy was confirmed, biopsies of the tumor cavity margins and remaining parenchyma were obtained to ensure the absence of residual tumor. Microdissection was performed for excision of selected enlarged tubules that were processed and cryopreserved. CONCLUSIONS We present a technique for microsurgical organ-sparing resection of testicular tumor and sperm extraction that can be used in selected infertile patients with azoospermia in whom incidental masses have been diagnosed by ultrasonography. This conservative approach should be especially considered for patients with a solitary testis or bilateral tumors. UROLOGY 73: 887-892, 2009. (C) 2009 Elsevier Inc.

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Objective: To determine the effects of melatonin on rat endometrium morphology and embryo implantation. Design: Experimental study. Setting: Federal University of Sao Paulo, Brazil. Animal(s): Forty female rats. Intervention(s): GI: control, GII: sham-operated, GIII: pinealectomized, and GIV: pinealectomized rats that received melatonin during 3 months. The GI, GII, and Gin groups received the vehicle of melatonin (NaCl + ethanol). At the end of the treatment, the animals were killed during the estrous phase; the uterus was removed for morphometric analysis. Urine was collected for 6-sulfatoxymelatonin. Blood was collected for estrogen (E) and progesterone (P) level determinations. In a second experiment, female rats were used to evaluate the endometrial embryo implantation. Main Outcome Measure(s): Endometrial morphology and embryo implantation. Result(s): Gin presented the highest values for endometrial area and thickness index, number of endometrial glands, and eosinophils. The number of vessels of groups I, II, and IV was fewer than that of Gin. The highest number of eosinophils was detected in Gin in comparison to other groups. The implantation rate in Gin was the lowest of all groups. This implantation rate was significantly increased and restored toward normal in GIV. Conclusion(s): Our data suggested that, in nonphotoperiodic animals such as rats, melatonin may positively affect the endometrial morphology and improve embryo implantation.

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An increased risk of early pregnancy loss in women briefly exposed to high levels of ambient particulate matter during the preconceptional period was recently observed. The effects of this exposure on early embryo development are unknown. This study was designed to assess the dose-response and biological effects of diesel exhaust particles (DEP) on in vitro embryo development using the in vitro fertilization (IVF) mouse model. Zygotes obtained from superovulated mice after IVF were randomly cultured in different DEP concentrations (0, 0.2, 2, and 20 mu g/cm(2)) for 5 days and observed for their capacity to attach and develop on a fibronectin matrix until day 8. Main outcome measures included blastocyst rates 96 and 120 h after insemination, hatching discriminatory score, total cell count, proportion of cell allocation to inner cell mass (ICM) and trophectoderm (TE), ICM morphology, attachment rate and outgrowth area, apoptosis and necrosis rates, and Oct-4 and Cdx-2 expression. Multivariate analysis showed a negative dose-dependent effect on early embryo development and hatching process, blastocyst cell allocation, and ICM morphology. Although blastocyst attachment and outgrowth were not affected by DEP, a significant impairment of ICM integrity was observed in day 8 blastocysts. Cell death through apoptosis was significantly higher after DEP exposure. Oct-4 expression and the Oct-4/Cdx-2 ratio were significantly decreased in day 5 blastocysts irrespective of DEP concentration. Results suggest that DEP appear to play an important role in disrupting cell lineage segregation and ICM morphological integrity even at lower concentrations, compromising future growth and viability of the blastocyst.

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To assess the potential effects of short-term exposure to particulate air pollution during follicular phase on clinical, laboratory, and pregnancy outcomes of women undergoing IVF/ET. Retrospective cohort study of 400 first IVF/ET cycles of women exposed to ambient particulate matter during follicular phase. Particulate matter (PM) was categorized into quartiles (Q(1): a parts per thousand currency sign30.48 A mu g/m(3), Q(2): 30.49-42.00 A mu g/m(3), Q(3): 42.01-56.72 A mu g/m(3), and Q(4): > 56.72 A mu g/m(3)). Clinical, laboratory, or treatment variables were not affected by follicular phase PM exposure periods. Women exposed to Q(4) period during the follicular phase of conception cycles had a higher risk of miscarriage (odds ratio, 5.05; 95% confidence interval: 1.04-25.51) when compared to women exposed to Q(1-3) periods. Our results show an association between brief exposure to high levels of ambient PM during the preconceptional period and early pregnancy loss, although no effect of this exposure on clinical, laboratory, and treatment outcomes was observed.

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Objective: To evaluate effects of pre- and/or postnatal exposure to ambient fine particulate matter on fertilization, embryo development, and cell lineage segregation in preimplantation blastocysts using the IVF mouse model. Design: Animal model. Setting: Academic institution. Animal(S): Six-week-old, superovulated mice. Intervention(s): Pre- and postnatal exposure to filtered air (FA-FA), filtered-ambient air (FA-AA), or ambient air (AA-AA) in exposure chambers 24 hours a day for 9 weeks. Main Outcome Measure(S): Gestation length, litter size, sex ratio, ovarian response to superovulation, fertilization rate, embryo development, blastocyst and hatching rates, total cell count, and proportion of cell allocation to inner-cell mass (ICM) and trophectoderm (TE). Result(S): Gestation length, litter size and birth weight, live-birth index, and sex ratio were similar among exposure groups. Ovarian response was not affected by the exposure protocol. A multivariate effect for pre- and/or postnatal exposure to ambient fine particulate matter on IVF, embryo development, and blastocyst differential staining was found. Cell counts in ICM and ICM/TE ratios in blastocysts produced in the FA-FA protocol were significantly higher than in blastocysts produced in the FA-AA and AA-AA protocols. No difference in total cell count was observed among groups. Conclusion(S): Our study suggests that exposure to ambient fine particulate matter may negatively affect female reproductive health by disrupting the lineage specification at the blastocyst stage without interfering in early development of the mouse embryo. (Fertil Steril (R) 2009;92:1725-35. (C) 2009 by American Society for Reproductive Medicine.)