Search results for "Inner cell mass"
showing 10 items of 15 documents
Rescuing monopronucleated-derived human blastocysts: a model to study chromosomal topography and fingerprinting.
2021
Objective To quantify the percentage of monopronuclear-derived blastocysts (MNBs) that are potentially useful for reproductive purposes using classic and state-of-the-art chromosome analysis approaches, and to study chromosomal distribution in the inner cell mass (ICM) and trophectoderm (TE) for intertissue/intratissue concordance comparison. Design Prospective experimental study. Setting Single-center in vitro fertilization clinic and reproductive genetics laboratory. Patient(s) A total of 1,128 monopronuclear zygotes were obtained between June 2016 and December 2018. Intervention(s) MNBs were whole-fixed or biopsied to obtain a portion of ICM and 2 TE portions (TE1 and TE2) and were subse…
Analysis of the morphological dynamics of blastocysts after vitrification/warming: defining new predictive variables of implantation
2017
Objective To describe the morphological dynamics of vitrified/warmed blastocysts and to identify quantitative morphological variables related to implantation. Subsequently, by using the most predictive parameters, to develop a hierarchical model by subdividing vitrified/warmed blastocysts into categories with different implantation potentials. Design Observational, retrospective, cohort study. Setting University-affiliated private IVF center. Patient(s) The study included 429 vitrified/warmed blastocysts with known implantation data, which were evaluated by time-lapse imaging. Blastocysts were routinely placed in EmbryoScope (Vitrolife) immediately after warming until transfer. Intervention…
Prediction of embryo survival and live birth rates after cryotransfers of vitrified blastocysts
2020
Which pre-vitrification parameters are the most predictive of survival and live birth in vitrified-warmed blastocyst transfer cycles?A retrospective study including 11,936 warmed blastocysts. Pre-vitrification morphological parameters analysed for blastocysts included day of vitrification; blastocyst expansion degree; trophoectoderm grade (A, B and C); and inner cell mass grade (A, B and C). Univariate and multivariate generalized estimating equations models were used to analyse survival, clinical pregnancy and live birth rate. A stepwise regression analysis was conducted to select and classify by order which outcomes were the most predictive.The odds of survival increased almost twice for …
Multicenter prospective study of concordance between embryonic cell-free DNA and trophectoderm biopsies from 1301 human blastocysts
2020
Background The recent identification of embryonic cell-free DNA in spent blastocyst media has opened a new era of possibilities for noninvasive embryo aneuploidy testing in assisted reproductive technologies. Yet, previous studies assessing a limited number of embryos reported variable concordance between embryonic cell-free DNA and trophectoderm biopsies, thus questioning the validity of this approach. Objective This study aimed to evaluate the concordance and reproducibility of testing embryonic cell-free DNA vs trophectoderm DNA obtained from the same embryo in a large sample of human blastocysts and to assess the contribution of the inner cell mass and trophectoderm to embryonic cell-fr…
Functional Genomics of 5-to 8-Cell Stage Human Embryos by Blastomere Single-Cell cDNA Analysis
2010
Blastomere fate and embryonic genome activation (EGA) during human embryonic development are unsolved areas of high scientific and clinical interest. Forty-nine blastomeres from 5- to 8-cell human embryos have been investigated following an efficient single-cell cDNA amplification protocol to provide a template for high-density microarray analysis. The previously described markers, characteristic of Inner Cell Mass (ICM) (n = 120), stemness (n = 190) and Trophectoderm (TE) (n = 45), were analyzed, and a housekeeping pattern of 46 genes was established. All the human blastomeres from the 5- to 8-cell stage embryo displayed a common gene expression pattern corresponding to ICM markers (e.g., …
Ultrastructure of preimplantation genetic diagnosis-derived human blastocysts grown in a coculture system after vitrification
2006
Objective To evaluate ultrastructural features of preimplantation genetic diagnosis (PGD) blastocysts before and after vitrification. Design Descriptive study of both vitrified and fresh hatching blastocysts. Setting PGD program at the Instituto Universitario, Instituto Valenciano de Infertilidad. Patient(s) Patients undergoing PGD donated their abnormal embryos for research (n = 26). Intervention(s) Biopsied embryos were cultured in the presence of human endometrial cells until day 6. Sixteen blastocysts were vitrified. A total of 11 high-scored hatching blastocysts, 6 warmed and 5 fresh, were fixed for ultrastructure. Main Outcome Measure(s) The cytoskeleton structure, type of intercellul…
Disruption of apical-basal polarity of human embryonic stem cells enhances hematoendothelial differentiation
2007
Abstract During murine development, the formation of tight junctions and acquisition of polarity are associated with allocation of the blastomeres on the outer surface of the embryo to the trophoblast lineage, whereas the absence of polarization directs cells to the inner cell mass. Here, we report the results of ultrastructural analyses that suggest a similar link between polarization and cell fate in human embryos. In contrast, the five human embryonic stem cell (hESC) lines displayed apical-basal, epithelial-type polarity with electron-dense tight junctions, apical microvilli, and asymmetric distribution of organelles. Consistent with these findings, molecules that are components of tigh…
Defining the genomic signature of totipotency and pluripotency during early human development.
2013
The genetic mechanisms governing human pre-implantation embryo development and the in vitro counterparts, human embryonic stem cells (hESCs), still remain incomplete. Previous global genome studies demonstrated that totipotent blastomeres from day-3 human embryos and pluripotent inner cell masses (ICMs) from blastocysts, display unique and differing transcriptomes. Nevertheless, comparative gene expression analysis has revealed that no significant differences exist between hESCs derived from blastomeres versus those obtained from ICMs, suggesting that pluripotent hESCs involve a new developmental progression. To understand early human stages evolution, we developed an undifferentiation netw…
Predictive variables of in vitro fertilization and pre-implantation embryo development in the mouse
2002
The present study aims to analyze the cause-effect relationships among several in-vitro fertilization and pre-implantation embryo development variables in the mouse. Superovulation of hybrid (C57Bl/6JIco female X CBA/JIco male) female mice of 4-6 weeks of age was induced by a priming injection of pregnant mare's serum gonadotropin at the estrus stage of the estrous cycle followed after a 48-hr interval by human chrorionic gonadotropin. Ovulated cumulus-enclosed oocytes were inseminated with sperm from hybrid males of 12-16 weeks of age. The multiple linear regression analyses performed indicated that (a) total number of ovulated oocytes is a good predictor of both fertilization frequency an…
Stage of the estrous cycle at the time of pregnant mare's serum gonadotropin injection affects pre-implantation embryo development in vitro in the mo…
2002
The present study aims to analyze in the mouse the effect of the stage of the estrous cycle at the time of pregnant mare's serum gonadotropin (PMSG) injection on fertilization of ovulated cumulus-enclosed oocytes and later embryo development in vitro to the blastocyst stage. Quality of blastocysts was evaluated by staining and counting of total number of nuclei, mitotic index, percentage of apoptotic nuclei, and cell allocation to the inner cell mass (ICM) and trophectoderm (TE) lineage. Superovulation of hybrid (C57Bl/6JIco female x CBA/JIco male) female mice of 4-6 weeks of age was induced by a priming injection of PMSG at different stages of the estrous cycle followed after a 48-hr inter…