Reflexiones sobre el workshop "Ensayos de habitar"

Partiendo de la hipótesis de que estudiar el habitar es un ejercicio procesual, se llevó a cabo, por primera vez en la II Bienal de Diseño FADU (2015), el Workshop “Ensayos del Habitar”. En el mismo, cada individuo, ejercita la concepción y construcción de las Prácticas Sociales a través del reconocimiento de sus cambios, componentes, estructuras variadas y modos que les dieron y dan forma. ¿Quiénes habitamos? ¿Cómo lo hacemos? ¿Cuándo se produce el cambio? Y más interrogantes.Es a través de exposiciones breves y disparadoras, por un lado y ejercicios lúdicos de creación, por otro, en donde se pone al alumno y al tutor en la difícil tarea de tomar distancia, conciencia y crítica de las muy variadas formas de habitar.Assuming that inhabit study is a procedural exercise, conducted for the first time in the II Biennial of Design FADU (2015), the Workshop "Inhabiting Trials". In it, each individual exercises the design and construction of Social Practices through recognition of their changes, components, structures and varied ways that has shaped, and is shaping them. Who inhabit? How do we do it? When change happens? And more questions. It is through short exhibitions that pull triggers on the one hand, and recreational creative exercises, on the other, where it gets the student and tutor in the difficult task of taking distance, awareness and a critical standing of the varied ways of living.Fill: Magali Ainstein, FADU-UBA, Buenos Aires, Argentin

Telling metabolic stories to explore metabolomics data: a case study on the yeast response to cadmium exposure

Artículo de publicación ISIMotivation: The increasing availability of metabolomics data enables to better understand the metabolic processes involved in the immediate response of an organism to environmental changes and stress. The data usually come in the form of a list of metabolites whose concentrations significantly changed under some conditions, and are thus not easy to interpret without being able to precisely visualize how such metabolites are interconnected. Results: We present a method that enables to organize the data from any metabolomics experiment into metabolic stories. Each story corresponds to a possible scenario explaining the flow of matter between the metabolites of interest. These scenarios may then be ranked in different ways depending on which interpretation one wishes to emphasize for the causal link between two affected metabolites: enzyme activation, enzyme inhibition or domino effect on the concentration changes of substrates and products. Equally probable stories under any selected ranking scheme can be further grouped into a single anthology that summarizes, in a unique subnetwork, all equivalently plausible alternative stories. An anthology is simply a union of such stories. We detail an application of the method to the response of yeast to cadmium exposure. We use this system as a proof of concept for our method, and we show that we are able to find a story that reproduces very well the current knowledge about the yeast response to cadmium. We further show that this response is mostly based on enzyme activation. We also provide a framework for exploring the alternative pathways or side effects this local response is expected to have in the rest of the network. We discuss several interpretations for the changes we see, and we suggest hypotheses that could in principle be experimentally tested. Noticeably, our method requires simple input data and could be used in a wide variety of applications. Availability and implementation: The code for the method presented in this article is available at http://gobbolino.gforge.inria.fr.European Research Council under the European Community’s Seventh Framework Programme (FP7/2007- 2013)/ERC grant agreement no. (247073)10; the French project (ANR MIRI BLAN08-1335497); and the ANR funded LabEx ECOFECT. It was partially supported by the Plateforme Bioinformatique de Toulouse, ANR-BBSRC Systryp, the CIRIC-INRIA Chile line Natural Resources, the NWO-CLS MEMESA project and the ‘DISCO’ PRIN National Research Project

Marked disturbance of calcium homeostasis in mice with targeted disruption of the Trpv6 calcium channel gene

We report the phenotype of mice with targeted disruption of the Trpv6 (Trpv6 KO) epithelial calcium channel. The mice exhibit disordered Ca(2+) homeostasis, including defective intestinal Ca(2+) absorption, increased urinary Ca(2+) excretion, decreased BMD, deficient weight gain, and reduced fertility. Although our Trpv6 KO affects the closely adjacent EphB6 gene, the phenotype reported here is not related to EphB6 dysfunction. INTRODUCTIOn: The mechanisms underlying intestinal Ca(2+) absorption are crucial for overall Ca(2+) homeostasis, because diet is the only source of all new Ca(2+) in the body. Trpv6 encodes a Ca(2+)-permeable cation channel responsible for vitamin D-dependent intestinal Ca(2+) absorption. Trpv6 is expressed in the intestine and also in the skin, placenta, kidney, and exocrine organs. MATERIALS AND METHODS: To determine the in vivo function of TRPV6, we generated mice with targeted disruption of the Trpv6 (Trpv6 KO) gene. RESULTS: Trpv6 KO mice are viable but exhibit disordered Ca(2+) homeostasis, including a 60% decrease in intestinal Ca(2+) absorption, deficient weight gain, decreased BMD, and reduced fertility. When kept on a regular (1% Ca(2+)) diet, Trpv6 KO mice have deficient intestinal Ca(2+) absorption, despite elevated levels of serum PTH (3.8-fold) and 1,25-dihydroxyvitamin D (2.4-fold). They also have decreased urinary osmolality and increased Ca(2+) excretion. Their serum Ca(2+) is normal, but when challenged with a low (0.25%) Ca(2+) diet, Trpv6 KO mice fail to further increase serum PTH and vitamin D, ultimately developing hypocalcemia. Trpv6 KO mice have normal urinary deoxypyridinoline excretion, although exhibiting a 9.3% reduction in femoral mineral density at 2 months of age, which is not restored by treatment for 1 month with a high (2%) Ca(2+) "rescue" diet. In addition to their deranged Ca(2+) homeostasis, the skin of Trpv6 KO mice has fewer and thinner layers of stratum corneum, decreased total Ca(2+) content, and loss of the normal Ca(2+) gradient. Twenty percent of all Trpv6 KO animals develop alopecia and dermatitis. CONCLUSIONS: Trpv6 KO mice exhibit an array of abnormalities in multiple tissues/organs. At least some of these are caused by tissue-specific mechanisms. In addition, the kidneys and bones of Trpv6 KO mice do not respond to their elevated levels of PTH and 1,25-dihydroxyvitamin D. These data indicate that the TRPV6 channel plays an important role in Ca(2+) homeostasis and in other tissues not directly involved in this process

Sensitivity to 3-NP of striatal cells expressing hMTH1 and wild-type or mutant murine <i>htt</i>.

<p>Striatal cells derived from wild-type Hdh<i>^Q7/Q7</i> and mutant <i>Hdh^Q111/Q111</i> mice were transfected with hMTH1. (A) Proteins were separated and probed with an antibody against hMTH1. (B) Intracellular localization of hMTH1 (green fluorescence) in <i>Hdh^Q111/Q111</i> and <i>Hdh^Q111/Q111</i>+hMTH1. Nuclei were counterstained by DAPI. (C) LDH release. LDH release from striatal cells into culture medium was measured 24 hr after continuous exposure to 20 mM 3-NP. Hdh<i>^Q7/Q7</i> (grey bar) and Hdh<i>^Q7/Q7</i>+hMTH1 (dashed bar); <i>Hdh^Q111/Q111</i> (black bars) and <i>Hdh^Q111/Q111</i>+hMTH1 (open bar). Mean±SE, n = 4. (D) Clonal survival. Cloning efficiency was determined at 33°C after 24 hr continuous exposure to the indicated 3-NP concentrations. Mean±SD, n = 2. (E) Coulter counter assay. Survival of non-proliferating cells measured in a Coulter Counter. Mean±SD, n = 3. The asterisks indicate significant differences by Student's <i>t</i>-test (p values = 0.02) between <i>Hdh^Q111/Q111</i> and <i>Hdh^Q111/Q111</i>+hMTH1.</p

Construction and characterization of a transgenic mouse expressing the <i>hMTH1</i> cDNA.

<p>(A) A BamH1-EcoRV fragment (509 bp) derived from pcDEBΔ <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1000266#pgen.1000266-Kang1" target="_blank">[23]</a> encoding the <i>hMTH1</i> cDNA was subcloned into the gWIZ vector under the control of the CMV promoter. This vector transfected into wild-type MEFs expressed the hMTH1 protein (data not shown). The MscI-KpnI fragment (2481 bp) was used in the construction of the transgenic mouse. (B) Determination of transgene copy number. Genomic DNA from mouse tails was analysed by Southern blot analysis (left panel). In the right panel 2, 5, 10, 20, 40 copies of the MscI-KpnI fragment were analysed. Both blots were probed with the same probe. Copy number was determined by comparison. The arrow indicates the DNA from the mouse that was used as a founder for the colony. (C) Analysis by FISH of the number of hMTH1 integrations in hemizygous (<i>hMTH1-Tg^+/−</i>) and homozygous (<i>hMTH1-Tg^+/+</i>) strains. (D) Expression of <i>hMTH1</i> mRNA. RT-PCR was performed using total RNA from the indicated organs and human specific primers. RT-PCR for the <i>GADPH</i> gene is used as an internal control. <i>hMTH1</i> and <i>GAPDH</i> fragments are respectively 200 bp and 330 bp. (E) Western blot analysis of transgene expression. Total proteins (20–40 µg) from a range of tissues were separated by SDS polyacrylamide electrophoresis, blotted and probed with an antibody against hMTH1. β-tubulin was used as a loading control.</p

KBrO₃ sensitivity of <i>hMTH1-Tg^+/+</i> and wild-type MEFs.

<p>Wild-type (closed symbols) and <i>hMTH1-Tg^+/+</i> (open symbols) MEFs were treated with KBrO₃ for 30 min at the indicated concentrations. Viability was measured by MTT assay 48 hr later. The graphs are the mean±SD of 3 independent experiments.</p