Introduction to Drugs and Pregnancy
“Bert” Bertis Britt Little in Drugs and Pregnancy, 2022
The period of the embryo is the critical stage of development for the induction of birth defects. The embryonic period extends from the time of implantation until 58–60 days post-conception. Organs and tissues are being formed (i.e., organogenesis) during this period. Random biological mistakes that occur during the embryonic period of the embryo may result in malformations (congenital anomalies) or birth defects. Agents that induce abnormal embryonic physical or physiological development by acting during the period of the embryo, or organogenesis are teratogens (Jones, 1988). Lethal embryo malformations present as spontaneous abortion, sometimes before pregnancy is recognized. Similarly, some substances that are directly toxic to the embryo, e.g., methotrexate, also present as spontaneous abortions. The critical times for the development of various organs and structures of the human embryo are given in Figure 1.2.
Use of Time-Lapse Embryo Imaging in Assisted Reproductive Technology Practice
Botros Rizk, Yakoub Khalaf in Controversies in Assisted Reproduction, 2020
Time-lapse cinematography was initially used by Payne et al. in 1997 to monitor embryonic development events (5). A decade later, Lemmen et al. identified embryonic kinetic markers correlated with implantation success (6). Currently, several time-lapse (TL) imaging systems are available for IVF. The three most commonly used ones are the Embryoscope, Primo Vision, and Eeva (Early Embryo Viability Assessment) systems. Technically, the Embryoscope is an incubator unit with an integrated TL system that uses a bright-field illumination with seven focal planes to visualize embryonic intracellular events at high resolution and project them over time. Primo Vision consists of small units that can be placed in a conventional incubator and uses bright-field illumination with 11 focal planes to monitor embryo development. The Eeva System is a microscopic TL system that uses a dark-field illumination with one focal plane to map cytokinetic division patterns of embryos with a very low resolution for intracellular details (7).
ECoG-Based BCIs
Chang S. Nam, Anton Nijholt, Fabien Lotte in Brain–Computer Interfaces Handbook, 2018
Penfield’s pioneering work in the 1950s with epilepsy patients represented the first comprehensive ECoG-based effort to study the neural basis of human behavior (Penfield and Rasmussen 1950). To this date, the large majority of human ECoG studies have been restricted to neurosurgical patients since the collection of ECoG signals requires surgery that consists of a craniotomy, followed by an incision to the protective dura matter for the placement of electrode arrays on the cortical surface. ECoG electrodes for human use are commonly made of platinum, platinum-iridium, stainless steel, or silver, and embedded into a thin flexible silastic sheet. The diameter of conventional clinical electrodes is typically 4 mm, with 2.3 mm of the contact exposed, and the interelectrode distance is usually 10 mm from center to center (see Figure 16.2). Electrode arrays can be arranged in square, rectangular, or L-shaped configurations. In the United States, the implantation duration is limited by the U.S. Food and Drug Administration (FDA) to a maximum of 28 days, and the typical implant duration is about 1 week. All relevant implant parameters (duration of the implant and size of the craniotomy) are determined solely by the clinical needs of the patients and without any regard for research interests.
Preliminary functional inquiry of lncRNA ENST00000433673 in embryo implantation using bioinformatics analysis
Published in Systems Biology in Reproductive Medicine, 2019
Dong Li, Weihua Jiang, Yiqun Jiang, Shanshan Wang, Junshun Fang, Lihua Zhu, Yinchun Zhu, Guijun Yan, Haixiang Sun, Linjun Chen, Ningyuan Zhang
Embryo implantation is a very complex and multifactorial biological behavior and includes the process of locating, attaching, and invading the active embryo, thereby attaching and synchronizing with the endometrium and establishing a connection. The positioning and adhesion of EECs with embryonic trophoblast cells is the first step in process of embryo implantation, and this step allows the embryos to adhere only during the short ‘planting window’ period, with the rest of the periods playing a role for providing natural cover for defence (Denker and Thie 2001). In previous studies, we found that lncRNA ENST00000433673 was significant and highly expressed in EECs, suggesting that lncRNA ENST00000433673 may regulate the function of EECs in embryo adhesion. Simultaneously, we extracted six adhesion-related target mRNAs (CD84, ITGAL, PCDHB9, CDHR3, PARVG, and CERCAM) through relevant bioinformatics analysis methods, which further confirmed that lncRNA ENST00000433673 is highly likely to be associated with embryo adhesion during embryo implantation. Through an interaction analysis of the protein network, we found that the ITGAL interacting mRNA, ICAM1, is an adhesion molecule that is extremely relevant to embryo adhesion.
Transcriptomic analysis of human endometrial stromal cells during early embryo invasion
Published in Annals of Medicine, 2021
Shuo Han, Minghui Liu, Shan Liu, Yuan Li
Embryo implantation is a dynamic and complex process in which embryo and endometrial cells are the key participants. The human endometrium consists of stromal cells, immune cells (mainly NK cells), and epithelial cells. To better understand the underlying mechanisms of embryo implantation, several novel methods and improved culture conditions have been developed and expanded. For instance, endometrial organoids recapitulate essential structures and functions of the receptive endometrium in vivo, embryo surrogates have been developed that include all three blastocyst lineages, and 3D systems have been developed, such as hydrogel-based 3D-bioprinting or micro moulding, to create microchannel systems within the tissue [27]. These more precise models can help to more accurately study the mechanisms of embryo implantation and invasion. However, the in vitro model employed in this study was not one of these more advanced methods and may be seen as a limitation of this study. We hope to improve upon this model in further research.
Current Concepts of the Uveitis-Glaucoma-Hyphema (UGH) Syndrome
Published in Current Eye Research, 2023
Meera S. Ramakrishnan, Kenneth J. Wald
The term “UGH syndrome” was coined by Ellingson in 1978.2 He described the typical syndromic features that occurred following secondary implantation of the Surgidev Mark VIII anterior chamber lens implant into eyes following intracapsular lens extraction. Of the 11 eyes that were implanted with this intraocular lens, 9 ultimately required removal due to complications (7 due to uncontrolled hemorrhage and 2 for uveitis). The clinical signs began at the earliest 2 months after implantation and no later than 9 months. Early intraocular lens design was characterized by poor finish quality, molding defects, and loop degradation.5 Surgical technique likely also contributed to the hemorrhagic and inflammatory outcomes as microsurgical techniques were still rudimentary at the time of Ellingson’s report.
Related Knowledge Centers
- Chorionic Gonadotropin
- Crosstalk
- Endocannabinoid System
- Pregnancy Test
- Embryo
- Uterus
- Pregnancy
- Animal Embryonic Development
- Blastocyst
- Gestation