Embryology

Tipos de ansiedad de parejas tratadas con fecundación asistida frente a la donación hipotética de embriones para investigación en una clínica privada en …

by Jorge Alberto Álvarez-Díaz

Development of extra-embryonic membranes and fluid compartments

by Glenn Baggott

Políticas públicas e investigación en embriones humanos

by Jorge Alberto Álvarez-Díaz

Mechanotransduction, PROX1, and FOXC2 Cooperate to Control Connexin37 and Calcineurin during Lymphatic-Valve Formation.

by Anna Pfenniger

Published in: Dev Cell. 2012 Feb 2. [Epub ahead of print]
Authors: Sabine A, Agalarov Y, Maby-El Hajjami H, Jaquet M, Hägerling R, Pollmann C, Bebber D, Pfenniger A, Miura N, Dormond O, Calmes JM, Adams RH, Mäkinen T, Kiefer F, Kwak BR, Petrova TV.

Lymphatic valves are essential for efficient lymphatic transport, but the mechanisms of early lymphatic-valve... more Lymphatic valves are essential for efficient lymphatic transport, but the mechanisms of early lymphatic-valve morphogenesis and the role of biomechanical forces are not well understood. We found that the transcription factors PROX1 and FOXC2, highly expressed from the onset of valve formation, mediate segregation of lymphatic-valve-forming cells and cell mechanosensory responses to shear stress in vitro. Mechanistically, PROX1, FOXC2, and flow coordinately control expression of the gap junction protein connexin37 and activation of calcineurin/NFAT signaling. Connexin37 and calcineurin are required for the assembly and delimitation of lymphatic valve territory during development and for its postnatal maintenance. We propose a model in which regionally increased levels/activation states of transcription factors cooperate with mechanotransduction to induce a discrete cell-signaling pattern and morphogenetic event, such as formation of lymphatic valves. Our results also provide molecular insights into the role of endothelial cell identity in the regulation of vascular mechanotransduction.

Embryology in the Qur'an: The 'Alaqah Stage

by Elias Kareem

Revised and updated version on an unpublished essay from September 2000. February 2012 (Last modified 6 March 2012, version 1.78).

The Qur’an mentions that human development passes through a number of distinct stages. These stages are descriptive of... more The Qur’an mentions that human development passes through a number of distinct stages. These stages are descriptive of the embryo’s external appearance and have been assigned special names. This essay focuses on the term ‘alaqah علقة – the second stage of human development. The essay is illustrated with a number of colour images.

Did secularism win out? The debate over the Human Fertilisation and Embryology Bill

by Steven Kettell

Taking the power of ideas seriously–the case of the United Kingdom's 2008 Human Fertilisation and Embryology Bill

by Steven Kettell

Taking the Power of Ideas Seriously: The Case of the 2008 Human Fertilisation and Embryology Bill

by Steven Kettell

Plac8 and Plac9, novel placental-enriched genes identified through microarray analysis

by Gustaaf de Ridder

External description of the embryonic development of the prawn, Macrobrachium americanum Bate, 1868 (Decapoda, Palaemonidae) based on the staging method

by Marcelo Garcia - Guerrero

Greek embryological calendars and a fragment from the lost work of Damastes,< i> On the Care of Pregnant Women and of Infants</i>

by Holt Parker

"Greek Embryological Calendars and a Fragment from the Lost Work of Damastes, On the Care of Pregnant Women and of Infants," CQ 49 (1999) 515-534.
http://www.jstor.org/stable/639876

Parker, Holt N. - Greek embryological calendars and a fragment from the lost work of Damastes, « On the care of... more Parker, Holt N. - Greek embryological calendars and a fragment from the lost work of Damastes, « On the care of pregnant women and of infants ». CQ 1999 N. S. 49 (2) : 515-534. • Damastes' embryological calendar, published here for the first time, outlines the typical development of children that are born 7, 8, 9 and 10 months after conception. His work has affinities with various other texts, especially the Pythagorean corpus, but is idiosyncratic in its acceptance of an 8-month child's viability.

Histological and Histochemical Aspects of the Chick Paraxial Mesoderm

by Akram Jaffar

Al-Salihi AR, Mobarak HJ & Jaffar AA (2003): Histological and Histochemical Aspects of the Chick Paraxial Mesoderm. Journal of Basic Medical Sciences. 3(3):176-179.

The somitomeres are spherical clusters of the paraxial mesenchymal cells. They were demonstrated only by the scanning... more The somitomeres are spherical clusters of the paraxial mesenchymal cells. They were demonstrated only by the scanning electron microscope. No light microscopic criteria were described for the developing somitomeres. In this study the lectin binding pattern of wheat germ agglutinin and succinylated wheat germ agglutinin was used to verify the histochemical specification of the segment identity in view of the previously described scheme of somitogenesis in chick embryos. The results  showed that recruitment of the paraxial mesodermal cells is acompanied by localization of N-acetylglucosamine; organization of these cells occured in association with intracellular accumulation of sialic acid, while the segmentation of the somites was correlated with diffusion of sialic acid in the paraxial mesodermal tissue.

The Time and Place of the Organism: Merleau-Ponty’s Philosophy in Embryo

by David Morris

Alter: Revue de phénoménologie 16 (2008): 69-86

Merleau-Ponty’s philosophy attempts to locate meaning—sense—within being. Space and time are thus ingredient in sense.... more Merleau-Ponty’s philosophy attempts to locate meaning—sense—within being. Space and time are thus ingredient in sense. This is apparent in his earlier studies of structure, fields, expression and the body schema, and the linkage of space, time and sense becomes thematic in Merleau-Ponty’s later thinking about institution, chiasm and reversibility. But the space-time-sense linkage is also apparent in his studies of embryogenesis. The paper shows this by reconstructing Merleau-Ponty’s critical analysis of Driesch’s embryology (in the nature lectures) to demonstrate how, for Merleau-Ponty, embryogenesis entails a principle of sense-generation that is irreducible to the plenitude of space or spatial distributions of material, yet is inseparable from being and spatial facts. This principle indicates a ‘depth’ or ‘hollow’ internal to “flat being,” in virtue of which being can create more sense than is yet given. The paper illuminates this ‘depth’ and the role of space in sense by turning to some recent scientific accounts—of bees deciding on new nesting places, of termites building mounds, and of embryogenesis—to suggest how space is inherently ingredient in the genesis of sense. This depends on turning from a concept of space as extensive to place as intensive, for it is the intensity of places, rather than the extensity of already delineated spaces, that affords sense generation.

The Place of Animal Being: Following Animal Embryogenesis and Navigation to the Hollow of Being in Merleau-Ponty

by David Morris

Research in Phenomenology 40 (2010): 188-218

This article pursues overlapping points about ontology, philosophical method, and our kinship with and difference from... more This article pursues overlapping points about ontology, philosophical method, and our kinship with and difference from nonhuman animals. The ontological point is that being is determinately different in different places not because of differences, or even a space, already given in advance, but in virtue of a negative in being that is regional and rooted in place, which Merleau-Ponty calls the “hollow.” The methodological point is that we tend to miss this ontological point because we are inclined to what I call transportable thinking, which conceives of things and spatial determinacy itself as being what they are independent of where they are. I argue that we are inclined this way because, in contrast to other animals, we have a weak sense of where we are. We are lost animals. To compensate for lostness, we abstract ourselves from place and conceptualize ourselves and things by way of a transportable, Cartesian “view from above.”