Retinoic acid signaling is required during early chick limb development

Retinoic acid signaling is required during early chick limb development

JA Helms, CH Kim, G Eichele and C Thaller

Development 122: 1385-1394.

Vitamin A Requirement for Early Cardiovascular Morphogenesis Specification in the Vertebrate Embryo: Insights from the Avian Embryo

Vitamin A Requirement for Early Cardiovascular Morphogenesis Specification in the Vertebrate Embryo: Insights from the Avian Embryo

Maija H. Zile

Experimental Biology and Medicine 229:598-606 (2004)

Figure 1. Ventral view of normal (N) and vitamin A–deficient (VAD) quail embryos at ~72 hrs of development. Note the looped heart (arrow) and the extensive vascular networks (arrowheads) in the normal embryo. The vitelline veins link the normal embryo to the extraembryonal circulation. In the VAD embryo, the heart does not loop, is enlarged and ballooned, has no chambers, and is closed at the site of the inflow tract. The extraembryonal vascular networks do not form in the VAD embryo, thus there is no circulation. The VAD embryo will die by ~3.5 days of development. There are no survivors.

Vangelis – Blade Runner Blues

En attendant l’atterrissage d’Atlantis

The deorbit burn is complete, and Atalntis&the crew have begun their descent to California!

@NASA

Catégorie Astronomie pour les papouilles qu’ils ont fait à Hubble

Wing-to-Leg Homeosis by Spineless Causes Apoptosis Regulated by Fish-lips, a Novel Leucine-Rich Repeat Transmembrane Protein

Wing-to-Leg Homeosis by Spineless Causes Apoptosis Regulated by Fish-lips, a Novel Leucine-Rich Repeat Transmembrane Protein

Adachi-Yamada, Takashi, Harumoto, Toshiyuki, Sakurai, Kayoko, Ueda, Ryu, Saigo, Kaoru, O’Connor, Michael B., Nakato, Hiroshi

Mol. Cell. Biol. 2005 25: 3140-3150 doi:10.1128/MCB.25.8.3140-3150.2005

:-)

Via @Freeplay

RT @edtheist If atheism is a religion, then sitting on my ass all day is a sport. << I'm a professional

Poe’s law example? Please, tell me that this isn’t real :

Atheist Scientists Hack Google To Show Ida Lemur Monkey Evolution Logo

hors sujet

voilà, que chacun se fasse son opinion, de quel côté est la haine?
Rédigé par : vincent fleury

Le commentaire n’est pas vraiment pertinent vis-à-vis du sujet ou de la discussion du blogpost, ni du trackback, qui l’a suscité.

J’aurais laissé passer volontiers s’il n’était devenu l’amorce d’une discussion avec une jeune fille qui dans certaines uchronies aurait été ma fille ou ma filleule¹. Nous avons pris l’habitude avec Elsa, 17 ans bientôt, de papoter via Skype de choses et d’autres et depuis quelques mois, qu’elle suit les blogs scientifiques, les problèmes “science & société”, incluant “science & religion”, sont abordés.

Hier soir le commentaire cité ci-dessus a été d’emblée évoqué : “quelle haine ?”

Systemic Inhibition of NF-κB Activation Protects from Silicosis

Systemic Inhibition of NF-κB Activation Protects from Silicosis.
Di Giuseppe M, Gambelli F, Hoyle GW, Lungarella G, Studer SM, et al. (2009)

PLoS ONE 4(5): e5689. doi:10.1371/journal.pone.0005689

Immunological Interactions between 2 Common Pathogens, Th1-Inducing Protozoan Toxoplasma gondii and the Th2-Inducing Helminth Fasciola hepatica

Immunological Interactions between 2 Common Pathogens, Th1-Inducing Protozoan Toxoplasma gondii and the Th2-Inducing Helminth Fasciola hepatica.

Miller CMD, Smith NC, Ikin RJ, Boulter NR, Dalton JP, Donnelly S. (2009)

PLoS ONE 4(5):e5692, doi:10.1371/journal.pone.0005692

horreur !

Also on the top 10 list is caffeine-free coffee from Cameroon. Coffea charrieriana is the first record of a caffeine-free species from Central Africa. The plant is named for Professor André Charrier, “who managed coffee breeding research and collecting missions at IRD (Institut de Recherche pour le Développement) during the last 30 years of the 20th century.

Via

The Extracellular Domain of Smoothened Regulates Ciliary Localization and Is Required for High-Level Hh Signaling

The Extracellular Domain of Smoothened Regulates Ciliary Localization and Is Required for High-Level Hh Signaling

Pia Aanstad, Nicole Santos, Kevin C. Corbit, Paul J. Scherz, Le A. Trinh, Willi Salvenmoser, Jan Huisken, Jeremy F. Reiter and Didier Y.R. Stainier

Current Biology (2009), doi:10.1016/j.cub.2009.04.053

[update] Je viens de tomber sur l’annonce de ce papier par EurekAlert.

The development of an organism is a complex process to which a dozen or hundreds of signaling molecules contribute. Some of these molecules have dozens of functions in the fruit fly and in humans alike. One of these molecules – Hedgehog – controls the development of, for example, the extremities, the central nervous system, the teeth, eyes, hair, lung and the gastrointestinal tract. “What is most remarkable: The cells are told what to do not only because the molecule is present but also by the different concentrations of the molecules in the tissue”, says group leader Pia Aanstad of the Institute for Molecular Biology of the University of Innsbruck. “The concentration of Hedgehog makes the thumb of the right hand grow on the left hand side and the thumb of the left hand grow on the right hand side.” Thus, scientists define Hedgehog as a morphogen – a signal that is concentration-dependent and controls the pattern formation of an organism. A mutation in this signaling pathway induces dramatic and embryonically lethal malformations in the early developmental stage such as the formation of just one central eye. Defects in the Hedgehog signaling pathway in humans are a cause for one of the most common birth defects – holoprosencephaly. “Hedgehog genes are not new in evolution and the signaling pathway functions in the fly, mouse, fish and in humans similarly”, says Pia Aanstad. In her research work she focuses on the zebra danio or zebra fish. Due to the short developmental cycle, the scientists are able to observe the development of the small tropic fish in fast motion. “We want to better understand how the cells process the signals of the signaling molecules and how they react.”