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This study was designed to evaluate the capacity of vitrified-warmed porcine immature oocytes to mature and to be fertilized using in vitro fertilization or intracytoplasmic sperm injection, and to determine the subsequent embryo development. Immature oocytes were vitrified using ethylene glycol and dimethylsulphoxide as cryoprotectants and the Cryolock method. After warming oocytes were cultured 44 h for maturation. Oocytes were randomly distributed in three treatment groups and subjected to in vitro fertilization (Experiment 1) or intracytoplasmic sperm injection (Experiment 2) procedures. The results indicate that the embryo development was higher in denuded oocytes co-cultured with granulosa cells (NkO-CC group) fertilized by in vitro fertilization or intracytoplasmic sperm injection compared to cumulus-cell oocyte complexes (COCs group), showing no significant differences with control. Vitrified denuded oocytes matured with a co-culture system NkO-CC group, displayed higher cleavage rate and blastocyst production than vitrified COCs group. Blastocysts were successfully obtained after IVF and ICSI procedures; however, the development to the blastocyst stage was better after IVF. These results show that the vitrification-warming media, the employment of a granulosa cell co-culture system and the Cryolock method during vitrification, increased the nuclear and cytoplasmic maturation of vitrified porcine immature oocytes. Further experiments are required to enhance porcine embryo production after vitrification., (Copyright © 2015 Elsevier Inc. All rights reserved.)

17β-amino-1,3,5(10)estratrien-3-ol (17βAE2), is the 17β-aminoestrogens prototype possessing anticoagulant activity, contrasting with the procoagulant effects of 17β-estradiol (17βE2). Its estrogenicity profile has not been reported, and it was evaluated by uterotrophic assay, estrogen receptor binding affinity and its ability to induce gene transcription of the human estrogen receptor (hER)α mediated in a Saccharomyces cerevisiae yeast expression system. Additionally, 17βAE2 and 17αAE2 were compared with 17βE2 in HeLa cells co-transfected with expression vectors for hERα or hERβ subtypes and for an estrogen-responsive reporter gene. Immature female CD1 mice and Wistar rats (21 days old) were treated for three days with 17βAE2 (10-5000 μg/kg), 17βE2 (0.001-1000 μg/kg) or vehicle (propylenglycol 10 ml/kg) and uterine weights were estimated. 17βAE2 increased uterine weight in a dose-dependent manner. The effective dose (ED)50 uterine weight values: 17βAE2=552 and 764 μg/kg (17βE2=4.8 and 16 μg/kg) and their relative uterotrophic potency were 0.86 and 2.1 (17βE2=100) in mice and rats, respectively. 17βAE2 competed with [(3)H]E2 for the estrogen receptor. The 17βAE2 relative binding affinities (RBAs) were: 0.074; Ki=2.2×10(-6)M (17βE2=100; Ki=1.6×10(-9)M); 0.029 and Ki=3.8×10(-6)M (17βE2=100; Ki=1.1×10(-9)M) for mice and rats uteri respectively. 17βAE2 activated hERα-mediated β-galactosidase transcription activity in the yeast system co-transfected with hERα gene. 17βAE2 effective concentration (EC)50=1.82 μM (17βE2=2.14 nM) with a relative potency of 0.12 (17βE2=100). These transactivation effects were abolished by the antagonist fulvestrant (ICI 182,780), similarly to 17βE2. 17βAE2 and 17αAE2 bind with low relative affinity to hERα and hERβ. Both induced hER-mediated reporter gene transactivation in a dose-response manner. The overall results provide evidence that 17βAE2 has a weak agonist estrogenic action greatly mediated through the hERβ and to a lesser extent the hERα at genomic level., (Copyright © 2014 Elsevier Ltd. All rights reserved.)