A Dual Stimuli Responsive Supramolecular Gel Provides Insulin Hydrolysis Protection and Redox-Controlled Release of Actives

Two supramolecular hydrogelators containing a central disulfide moiety and terminal carboxylic acid groups are studied. On the one hand, the hydrogels are responsive to a reductive environment, which transforms the disulfide unit to the corresponding thiols. On the other hand, the hydrogels show pH response associated with the presence of carboxylic acid units. Gels are formed at pH below ≈4 while at higher pH values, ionization of the gela-tors provokes gel disassembly. The properties of the gel are exploited for the release, as a proof of concept, of Bromophenol Blue in the presence of the reducing species tris(2-carboxyethyl)phosphine hydrochloride. Additionally, insulin is loaded into the hydrogels and protected from hydrolysis with simu-lated gastric fluid containing pepsin. Quantitative release of unaltered insulin, checked with an enzyme-linked immunosorbent assay colorimetric assay, is observed upon treatment with pH 7.4 buffer. This behavior would permit the use of the new hydrogels for oral insulin deliver

From the Molecular Biology to the Gene Therapy of a DNA Repair Syndrome: Fanconi Anemia

Diseases & disorder

Applying Prolog to Develop Distributed Systems

Development of distributed systems is a difficult task. Declarative programming techniques hold a promising potential for effectively supporting programmer in this challenge. While Datalog-based languages have been actively explored for programming distributed systems, Prolog received relatively little attention in this application area so far. In this paper we present a Prolog-based programming system, called DAHL, for the declarative development of distributed systems. DAHL extends Prolog with an event-driven control mechanism and built-in networking procedures. Our experimental evaluation using a distributed hash-table data structure, a protocol for achieving Byzantine fault tolerance, and a distributed software model checker - all implemented in DAHL - indicates the viability of the approach

Experiencias caseras que muestran aspectos del funcionamiento de la vista, el gusto y el tacto

En el laboratorio de Biología explicamos el funcionamiento de algunos de nuestros órganos de los sentidos (vista, olfato, gusto y tacto) a través de una serie de experiencias que a lo largo de los años han evidenciado ser muy didácticas. Muestran parte del proceso físico en sí y, al exigir la participación activa del alumnado, permiten que éste aprenda divirtiéndose. Lo fácil y barato que resulta realizar estas experiencias, junto a su gran capacidad degenerar asombro, invitan a su difusión y ejecución a todos los niveles

Learning Chemistry with candies

Las golosinas (caramelos, chicles, nubes, palotes, papas fritas, etc.) nos gustan a casi todos y gozan de una imagen positiva, a pesar de sus efectos secundarios si no se consumen con moderación. Aprovechándonos de esa buena imagen y de la gran variedad de golosinas que existen en el mercado, hemos diseñado una serie de experimentos con los que podemos explicar distintos tipos de reacciones químicas (acido-base, oxidación-reducción, endotérmicas…), la actuación de un indicador e, incluso, podemos comparar cantidades de vitamina C. En todas las actividades se persigue explicar algún aspecto de la Química que, en general, el público desconoce, captando su atención, por ejemplo, mediante cambios de color espectaculares y con las golosinas como protagonistas. Así mismo, estas experiencias pueden emplearse como recursos didácticos para alumnos de 4o E.S.O. y Bachillerato, apoyando los contenidos teóricos del currículum

Easy-to-implement experiences that show some aspects of how the senses of sight, taste and touch work

En el laboratorio de Biología explicamos el funcionamiento de algunos de nuestros órganos de los sentidos (vista, olfato, gusto y tacto) a través de una serie de experiencias que a lo largo de los años han evidenciado ser muy didácticas. Muestran parte del proceso físico en sí y, al exigir la participación activa del alumnado, permiten que éste aprenda divirtiéndose. Lo fácil y barato que resulta realizar estas experiencias, junto a su gran capacidad de generar asombro, invitan a su difusión y ejecución a todos los niveles

Endangered Lupinus mariae-josephae species: conservation efforts

A lupin endemism, Lupinus mariae-josephae (Lmj), singularly has been identified in the Valencia province, in Eastern Spain. This lupin thrives in alkaline-limed soils with high pH, a unique habitat for lupins, from a small area in Valencia region. In these soils, Lmj grows in just a few small, defined patches, and previous conservation efforts directed towards controlled plant reproduction have been unsuccessful. This lupin was thought to be extinct in Valencia until 2007, when it was discovered in a limestone patch. The reasons behind Lmj endangered status are presently unknown. This study will focus on the symbiosis between Lmj and rhizobia, and how this relationship might impact the population size of Lmj. We have previously shown that Lmj plants establish a specific root nodule symbiosis with bradyrhizobia present in those soils, and we reasoned that the paucity of these bacteria in soils might contribute to the lack of success in reproducing plants for conservation purposes

Symbiosis of the endangered Lupinus mariae-josephae lupin especies: Successful "in situ" propagation with rhizobial inoculation

Region, in Eastern Spain. This lupine thrives in alkaline soils with high pH, a unique habitat for lupines. In these soils, Lmj grows in just a few defined patches, and previous conservation efforts directed towards controlled plant reproduction have been unsuccessful. A legislative decree (70/2009, page 20156 Anex I) published in the el 'Diario Oficial de la Comunitat Valenciana' shows Lmj in a category corresponding, in the latest version of the Red List of IUCN (IUCN, 2012) (International Union for Conservation of Nature and Nature Resources), to an ?Endangered? legume species not extinct in the wild. Most current IUCN criteria used to define rare, small-range legume species, are based on history of reproductive traits such as number of pods and seeds. We have previously shown that Lmj plants establish a specific root nodule symbiosis with bradyrhizobia present in those soils, and we reasoned that the paucity of these bacteria in soils might contribute to the lack of success in reproducing plants for conservation purposes. Greenhouse experiments using Lmj trap-plants showed an absence, or very low concentration, of Lmj-nodulating bacteria in ?terra rossa? soils of Valencia outside of Lmj plant patches. No Lmj endosymbiotic bacteria were found in ?terra rossa? or alkaline red soils outside the Valencia Lmj endemism region in the Iberian Peninsula or Balearic Islands. Among the rhizobia able to establish an efficient symbiosis with L. mariae-josephae plants, two Bradyrhizobium sp. strains, LmjC and LmjM3, were selected as inocula for seed coating. Two planting experiments were carried out in consecutive years under natural conditions in areas with edapho-climatic characteristics identical to those sustaining natural Lmj populations, and successful reproduction of the plant was achieved. Interestingly, the successful reproductive cycle was absolutely dependent on seedling inoculation with effective bradyrhizobia, and optimal performance was observed in plants inoculated with LmjC, a strain that had previously shown the most efficient behavior under controlled conditions. These results define conditions for L. mariae-josephae conservation and for extension to alkaline-limed soil habitats, where no other known lupine can thrive. Broadly speaking, the work singularly identified the rhizobial symbiosis as a factor affecting the conservation of legumes and often being exceedingly vulnerable to threats. Our results also indicate that seed inoculation with N2-fixing, efficient Rhizobium strains is a strategy to consider in the conservation of endangered legume specie