Knock-Down of Specific Thyroid Hormone Receptor Isoforms Impairs Body Plan Development in Zebrafish

The role of thyroid hormones (THs) in development has been extensively studied, however, the specific molecular mechanisms involved are far from being clear. THs act by binding to TH nuclear receptors (TR) that act as ligand-dependent transcription factors to regulate TH-dependent gene expression. Like vertebrates, zebrafish express different isoforms of functional Tr alpha and beta, some of which can bind alternative ligands like 3,5-T2. In this study, we first analyzed the effects of exogenous T3 and 3,5-T2 exposure during embryogenesis. The percentage of affected embryos was similar to those vehicle-injected, suggesting that the early exposure to low TH levels is not sufficient to elicit effects upon the phenotype of the embryo. We then generated crispants for four isoforms of thr to learn more about the role of these receptors in early development. We found that crispant larvae from thraa and a newly identified l-thrb+, but not thrab and canonical thrb1 showed profound deleterious effects upon symmetry and laterality, suggesting early novel roles for these Tr isoforms in the body plan developmental program. Since critical events that determine cell fate start in the late gastrula, we tested if some genes that are expressed during early developmental stages could indeed be TH targets. We identify early development genes, like sox10 and eve, that were specifically over-expressed in thraa and l-thrb+ crispants, suggesting that these specific thr isoforms function as transcription repressors for these genes, while transcription of zic and ets appear to be thraa and l-thrb+-mediated, respectively. Overall, present results show that TH signaling participates in early zebrafish development and identify Tr isoform-specific mediated regulation of early gene expression

Without thyroid hormones there are no neurones

Tema del mesEl “saber popular” asocia glándula u hormonas tiroideas con sobrepeso u obesidad, ignorando, usual y desafortunadamente, la enorme importancia que ellas tienen en el crecimiento y desarrollo del organismo, especialmente en el del cerebro fetal y del recién nacido. En este trabajo, el lector interesado encontrara una revisión sencilla e inclusive coloquial, acerca de los principales aspectos de lo que hasta ahora se conoce sobre estas acciones “neurogénicas” de la glándula y sus hormonas. Conocerá que para la síntesis adecuada de hormonas tiroideas o TH, es crucial el aporte suficiente de yodo en la dieta, ya que sin yodo no hay TH. Probablemente le parecerá demasiado “técnico” saber que son y cómo se producen las TH. Sin embargo, con ello en mente, le resultara relativamente más fácil, entender los requisitos que estas hormonas tienen que satisfacer para ejercer sus efectos. Ese lector que confiamos leerá nuestro trabajo, podrá enterarse de las respuestas, hasta la fecha las más verosímiles, sobre las siguientes preguntas: ¿cómo ingresan las TH a las células?; ¿qué les pasa una vez que entraron?; ¿Cómo actúan?Popular knowledge associates thyroid gland or their hormones with overweight or obesity, usually and unfortunately ignoring the key role that they play during growth and development of organisms, especially for the fetal and newborn brain. In this article, the interested reader will find a simple and even colloquial review on the main aspects of what is currently known about these “neurogenic” actions of the gland and its hormones. The reader will recognize that a sufficient dietary iodine intake is crucial for the proper synthesis of thyroid hormones or TH, since without iodine there are no TH. It will probably seem too “technical” to know what TH are and how they are produced. However, with this in mind, it will be relatively easy to understand the requirements that these hormones must meet to exert their effects. That reader who we trust reads our work, will be able to find out the until now more plausible answers to the following questions: How do TH enter the cells? What happens to them once they got in?; How do they work

Hecho en México para ojos extranjeros: uso y menosprecio de referentes identitarios nacionales en el diseño de productos de consumo

The Mexican cultural identity, with its pre-Hispanic values and ethnic wealth, is a vast source of conceptual, symbolic and visual references for the construction of communication pieces, graphic identity and packaging design for products and services of national origin, however, this resource is usually taken advantage of only when it is oriented towards the tourism sector, since its use in consumer products is usually considered to be of lower value or quality by the consumer. This analysis aims to highlight this situation, as well as to contrast the creative and commercial potential that can be derived from the use of national identity references in package design and communication. At present there are few cases in which this potential is exploited in the design of pieces that will be distributed on a daily basis in the Mexican national territory, being the most common to find goods that replicate visually and conceptually various graphic tendencies emanated or used in the North American market, having an impact on a limited and sporadic creation of value through brands with Mexican cultural identity, diluting the possibility of endowing them with a high symbolic, historical and communicational value.A identidade cultural mexicana, com os seus valores prehispánicos e riqueza étnica, são uma vasta fonte de referências conceptuais, simbólicas e visuais para a construção de peças de comunicação, identidade gráfica e desenho de recipientes para produtos e serviços de origem nacional, contudo, este recurso só, normalmente, é aproveitado quando se orienta ao setor turístico, ja que o seu uso em produtos de consumo diário no mercado mexicano costuma ser considerado como de menor valor ou qualidade por parte do consumidor. Esta análise pretende evidenciar esta situação , assim como contrastar o potencial creativo e comercial que pode aportar o uso de referências identificativos nacionais no desenho de recipiente e comunicação. Atualmente, são poucos os casos em que esse potencial é explorado no desenho de peças que serão distribuídas diariamente no território nacional mexicano, sendo a mais comum encontrar mercadorias que reproduzam visual e conceitualmente várias tendências gráficas emanadas ou utilizadas o mercado norte-americano, tendo impacto em uma criação limitada e esporádica de valor através de marcas com identidade cultural mexicana, diluindo a possibilidade de dotá-los de um alto valor simbólico, histórico e comunicacional.La identidad cultural mexicana, con sus valores prehispánicos y riqueza étnica, es una vasta fuente de referentes conceptuales, simbólicos y visuales para la construcción de piezas de comunicación, identidad gráfica y diseño de envases para productos y servicios de origen nacional, sin embargo, este recurso sólo suele ser aprovechado cuando se orienta al sector turístico, ya que su uso en productos de consumo habitual suele ser considerado como de menor valor o calidad por parte del consumidor. Este análisis pretende evidenciar ésta situación, así como contrastar el potencial creativo y comercial que puede aportar el uso de referentes identitarios nacionales en el diseño de envase y comunicación. En la actualidad son pocos los casos en los que este potencial se explota en el diseño de piezas que habrán de distribuirse de manera cotidiana en el territorio nacional mexicano, siendo lo más común encontrar mercancías que replican visual y conceptualmente diversas tendencias gráficas emanadas o empleadas en el mercado norteamericano, repercutiendo con ello en una limitada y esporádica creación de valor a través de marcas con identidad cultural mexicana, diluyendo la posibilidad de dotarlos de un alto valor simbólico, histórico y comunicacional

Reduction of the closure time of postoperative enterocutaneous fistulas with fibrin sealant

AIM: To assess whether the use of fibrin sealant shortens the closure time of postoperative enterocutaneous fistulas (ECFs)