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Perinatal and Pediatric Outcome of Pregnancies Following PGT-M/SR/A
Published in Carlos Simón, Carmen Rubio, Handbook of Genetic Diagnostic Technologies in Reproductive Medicine, 2022
Malou Heijligers, Christine de Die-Smulders
Another known risk of ART is the increased risk of multiple conceptions, which consequently increases the risk of obstetric complications [34]. Over the years, the risk for multiple pregnancies following IVF has fallen due to stringent rules regarding the number of transferred embryos, where single embryo transfer (SET) is highly recommended [35]. Though studies report a higher prevalence of monozygotic twinning after SET in IVF with and without PGT, compared with live births after spontaneous conception [36–39]. The underlying mechanism is not fully understood, but it is hypothesized that the use of zona pellucida manipulating techniques may contribute to this risk [36–38]. Pregnancies following PGT therefore may have an increased risk of monozygotic twinning and accompanying obstetric risks.
Fertilization and normal embryonic and early fetal development
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
Asim Kurjak, Ritsuko K. Pooh, Aida Salihagic-Kadic, Iva Lausin, Lara Spalldi-Barisic
Already few minutes after the ovulation, oocyte is located in the ampullar part of the fallopian tube. It is surrounded by the zona pellucida. On the surface of the zona pellucida, there are few rows of the granulosa cells that make corona radiata. At the periphery of the corona radiata are left cells of cumulus oophorus. Often, these three units are called oocyte–corona–cumulus complex. Capability for the fertilization is limited: oocyte can be fertilized only 6 to 12 hours after the ovulation. Sperms are capable for fertilization 48 to 72 hours, until they are movable. Fertilization occurs in the ampullar part of the fallopian tube. The process of fertilization begins with conditioning of the spermatozoon in the male and female reproductive tracts. Thereafter, fertilization involves not only the egg itself but also the various investments that surround the egg at the time it is released from the ovary follicle. Fertilization, therefore, is not an event; it is a complex biochemical process requiring a minimum of 24 hours to complete syngamy (formation of a diploid set of chromosomes). During that process, there is no commingling of maternal and paternal chromosomes within a single nuclear membrane (pre-zygote); after this process, the paternal chromosome material is commingled (zygote). The most important activity of this new cell is the recognition of the new genome that presents the principal information center for the development of the human being and for all its further activities.
Capacitation, the Acrosome Reaction, and Motility in Mammalian Sperm
Published in Claude Gagnon, Controls of Sperm Motility, 2020
Susan S. Suarez, John W. Pollard
In 1982, Florman and Storey demonstrated that the zona pellucida induces the acrosome reaction in mouse sperm.55 Since then, the zona has also been demonstrated to have acrosome reaction-inducing activity in hamsters, rabbits, cattle, pigs, and humans.56-61 In the mouse, an 83-kDa glycoprotein component of the zona, named ZP3, has been shown to account for both the sperm binding and acrosome reaction-inducing activities of the zona pellucida (for review, see Reference 2). Both 55-kDa and 90-kDa glycoproteinaceous components of the porcine zona pellucida have acrosome reaction-inducing activity.59
Protein transduction domain of translationally controlled tumor protein: characterization and application in drug delivery
Published in Drug Delivery, 2022
Delivery of siRNA using TCTP-PTD across zona pellucida (ZP) in mouse oocytes was reported by Jeon et al (Jeon et al., 2019). The zona pellucida, a glycoprotein matrix that surrounds the biological membranes of embryos and oocytes, limits the permeation of exogenous molecules into mammalian embryos and oocytes during prolonged in vitro culture (Wassarman, 2008; Gupta et al., 2012). This group previously found that overexpression of TCTP can attenuate the time-dependent quality deterioration and apoptosis of oocytes (Jeon et al., 2017). Here, the exogenous TCTP, a form of recombinant TCTP-mCherry, also relieved the quality decline of oocytes when added to culture media, which in turn improved the fertilization capacity and subsequent development of early embryos (Jeon et al., 2019). TCTP-mCherry protein devoid of PTD showed impermeability, confirming the PTD-dependent translocation of TCTP.
Participation of signaling proteins in sperm hyperactivation
Published in Systems Biology in Reproductive Medicine, 2022
Joaquín Cordero-Martínez, Guadalupe Elizabeth Jimenez-Gutierrez, Charmina Aguirre-Alvarado, Verónica Alacántara-Farfán, Germán Chamorro-Cevallos, Ana L. Roa-Espitia, Enrique O. Hernández-González, Lorena Rodríguez-Páez
Sperm that reach the female genital tract enter into a different environment and undergo a highly selective process mediated by the cervical mucus (Holt and Fazeli 2016), which reduces the number of sperms from millions in the uterus to hundreds in the oviduct (Mahé et al. 2021). In humans, once the sperm reaches the oviduct, it attaches to the oviductal wall (Mahé et al. 2021), and a small population is released from the sperm reservoir due to numerous factors including oviductal secretions and hyperactivation (Gervasi and Visconti 2016; Okabe 2018). Hyperactivation is described as a fast whip movement of the flagellum with an irregular trajectory and an asymmetrically flagellum bend (Plant et al. 2014), and is accompanied by several physiological changes collectively known as capacitation. The acquisition of hyperactivation helps the sperm to reach the oocyte and penetrate through the components of the zona pellucida (ZP) to perform fertilization (Puga Molina, Luque, et al. 2018).
Oocyte maturation arrest produced by TUBB8 mutations: impact of genetic disorders in infertility treatment
Published in Gynecological Endocrinology, 2020
María C. Lanuza-López, Sandra G. Martínez-Garza, Jesús F. Solórzano-Vázquez, Daniela Paz-Cervantes, Claudia González-Ortega, Israel Maldonado-Rosas, Gerardo Villegas-Moreno, Lina G. Villar-Muñoz, Francisco A. Arroyo-Méndez, Antonio M. Gutiérrez-Gutiérrez, Raul E. Piña-Aguilar
We report three patients with IVF cycles in whom no mature oocytes or progessing to embryo MII-oocytes were found. In the second IVF cycles of patients 1 and 2 double trigger with hCG and GnRH analog was used for overcome the first failed cycles. No morphological abnormalities (Figures 2 and 3) were found in oocytes to suspect a zona pellucida defect. In patient 1 diagnosis was complicated by the presence of hypogonadism produced by a hypophyseal microadenoma and the fact that sister has oocyte donation in her IVF cycles preventing the confirmation of an oocyte maturation defect. All cases were diagnosed as oocyte maturation defects of monogenic origin, potentially involving TUBB8 or PATL2, before exome sequencing by a geneticist with experience in reproductive genetics.