Ion Channels in Human Pluripotent Stem Cells and Their Neural Derivatives
Long-Jun Wu in Nonclassical Ion Channels in the Nervous System, 2021
Though mouse and other animal models have provided valuable insight into brain development, functions, and diseases, we cannot neglect the differences between human and other organisms in gene expression patterns and pathophysiological properties. The scarce availability of live and functional human brain tissue has limited our ability to understand mechanisms underlying neurological diseases. The ability of human pluripotent stem cells (PSCs), comprised of human induced pluripotent stem cells (hiPSCs) and human embryonic stem cells (hESCs), to self-renew and differentiate into any types of cells in our body provides a novel and powerful tool to understand human brain development and pathology. Human ESCs are pluripotent cells derived from the inner cell mass of blastocyst embryos.
Implantation and Embryonic Imaging
Mary C. Peavey, Sarah K. Dotters-Katz in Ultrasound of Mouse Fetal Development and Human Correlates, 2021
The fertilized oocyte is known as the zygote, which will continue to divide into an embryo. Changes within the endometrium in early pregnancy can be easily identified by ultrasonography, in which the endometrium appears increased in echogenicity and thickness, in both the human as well as the mouse. The blastocyst consists of a discrete inner cell mass, within a spherical cavity lined by the trophectoderm cell layer. In humans, by the end of the third gestational week, the blastocyst begins to implant into the decidualized endometrium. A gestational sac is identified as a small, round, anechoic fluid collection surrounded by the hyperechoic rim of endometrial tissue. In humans, the position of the gestational sac should be in the mid to upper uterus. The shape should be round and fairly spherical in its dimensions. A pseudogestational sac can sometimes be seen in the instance of an ectopic or extra-uterine pregnancy, but would not contain a yolk sac.
Eicosanoid Binding Sites in Ovarian and Uterine Tissues
Murray D. Mitchell in Eicosanoids in Reproduction, 2020
The list of eicosanoid actions in ovarian and uterine tissues is incomplete and the mechanisms of action are complex and very poorly understood at best. The interaction between 5-and 15-lipoxygenases gives rise to lipoxins A and B, which have potent biological effects different from those caused by other eicosanoids. The eicosanoid structure binding-activity relationships have been summarized. The eicosanoids that bind to ovarian sites perhaps come from three major tissue sources: luteal cells, nonluteal ovarian cells, which include granulosa, theca, and stromal cells as well as nonluteal cells in corpus luteum, and the uterus. Eicosanoids have contractile and noncontractile actions in the uterus. The role of eicosanoids in the onset and progress of labor, ovum and sperm transport in the female reproductive tract, uterine blood flow, etc. is mediated by the contractile actions. Eicosanoids are also involved in endometrial changes required for blastocyst implantation.
Live birth following a single oocyte fertilized with ICSI and embryo biopsy at blastocyst stage: a case report
Published in Gynecological Endocrinology, 2020
Romualdo Sciorio, Elena Antonini, Bruno Engl
In this report, we present a case of a couple who obtained a live birth with a single oocyte fertilized by ICSI. Two oocytes were collected at 35.5 hours (h) post trigger and both were at metaphase II when sperm injection was performed (38 h). At 18 h post injection, one oocyte was fertilized, developed to the blastocyst stage and underwent to trophectoderm biopsy for preimplantation genetic testing on day 5. Following biopsy, the blastocyst was vitrified and 4 h after warming procedure, the euploid blastocyst was replaced to the uterine cavity. Healthy live birth was obtained after 39 weeks of gestation.
Proteomic analysis of bovine blastocoel fluid and blastocyst cells
Published in Systems Biology in Reproductive Medicine, 2014
Pernille Linnert Jensen, Marie Louise Grøndahl, Hans Christian Beck, Jørgen Petersen, Lotte Stroebech, Søren Tvorup Christensen, Claus Yding Andersen
The understanding of the early mammalian development is a prerequisite for the advancement of in vitro fertilization and improvement of derivation and culturing of embryonic stem cells. While, whole genome transcriptomic analysis on bovine blastocysts has identified genes active in early development, little information is available about the protein complement of early embryos. Modern, sensitive proteomic technology (nano HPLC tandem mass spectrometry) allowed us to describe the proteome of the scarce blastocoel fluid and cell material of expanded bovine blastocysts isolated by micromanipulation. From two independent replicates, 23 proteins were identified in the blastocoel fluid while 803 proteins were identified in the remaining cell material. The proteins were grouped into categories according to their gene ontology (GO) terms by which proteins involved in cell differentiation, cell proliferation, development, and reproduction could be derived. Proteins classified in these categories could be candidates for further functional studies to understand pluripotency and early mammalian development.
Pregnancy outcome after blastocyst stage transfer comparing to early cleavage stage embryo transfer
Published in Gynecological Endocrinology, 2015
Elham Aziminekoo, Maryam Sadat Mohseni Salehi, Vahid Kalantari, Ensieh Shahrokh Tehraninejad, Fedyeh Haghollahi, Batool Hossein Rashidi, Zahra Zandieh
Blastocyst transfer has been introduced as an alternative for improving the chance for in vitro fertilizations (IVF) implantation. The present study was to evaluate pregnancy rates when embryo transfer was performed either on day 2–3 (cleavage stage) or on day 4–5 (blastocyst stage). This randomized clinical trial included 118 infertile women. All the study subjects underwent controlled ovarian stimulation using a long protocol and randomized into two groups. BS group (n = 57), the culture was extended to day 5 (blastocyst stage) and in the CS-group (n = 61), embryo culture was continued to day 3 (cleavage stage). Ongoing pregnancies, abortion, implantation rate were evaluated. No significant differences were seen in the pregnancy rate between the two groups (33.3% in the BS group versus 27.9% in the CS group; p = 0.519). Abortion, implantation rate in two groups are not significant. Despite the lack of statistical difference between the two study groups, our data suggest that blastocyst transfer may be associated with a higher pregnancy and an overall better implantation rates. However, further studies with larger sample size are mandatory to confirm these findings.
Related Knowledge Centers
- Embryonic Stem Cells
- Morula
- Placenta
- Embryo
- Endometrium
- Mammals
- Mammalian Embryo