Silicon nanopillar arrays with SiO2 overlayer for biosensing application

We present the fabrication of silicon dioxide (SiO2) coated silicon nanopillar array structures and demonstrate their application as sensitive optical biosensors. Colloidal lithography, plasma dry etching and deposition processes are used to fabricate SiO2 coated Si nanopillar arrays with two different diameters and periods. Proof of concept bio recognition experiments are carried out with the bovine serum albumin (BSA)/antiBSA model system using Fourier transform visible and IR spectrometry (FT-VIS-IR) in reflection mode. A limit of detection (LoD) value of 5.2 ng/ml is estimated taking in to account the wavenumber uncertainty in the measurements

Hsp70 and Hsp40 inhibit an inter-domain interaction necessary for transcriptional activity in the androgen receptor.

Molecular chaperones such as Hsp40 and Hsp70 hold the androgen receptor (AR) in an inactive conformation. They are released in the presence of androgens, enabling transactivation and causing the receptor to become aggregation-prone. Here we show that these molecular chaperones recognize a region of the AR N-terminal domain (NTD), including a FQNLF motif, that interacts with the AR ligand-binding domain (LBD) upon activation. This suggests that competition between molecular chaperones and the LBD for the FQNLF motif regulates AR activation. We also show that, while the free NTD oligomerizes, binding to Hsp70 increases its solubility. Stabilizing the NTD-Hsp70 interaction with small molecules reduces AR aggregation and promotes its degradation in cellular and mouse models of the neuromuscular disorder spinal bulbar muscular atrophy. These results help resolve the mechanisms by which molecular chaperones regulate the balance between AR aggregation, activation and quality control

Transparent nanometric organic luminescent films as UV-active components in photonic structures

A new kind of visible-blind organic thin-film material, consisting of a polymeric matrix with a high concentration of embedded 3-hydroxyflavone (3HF) dye molecules, that absorbs UV light and emits green light is presented. The thin films can be grown on sensitive substrates, including flexible polymers and paper. Their suitability as photonic active components photonic devices is demonstrated. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Author Correction: Hsp70 and Hsp40 inhibit an inter-domain interaction necessary for transcriptional activity in the androgen receptor.

An amendment to this paper has been published and can be accessed via a link at the top of the paper

Biomolecular Interaction Analysis of Gestrinone-anti-Gestrinone Using Arrays of High Aspect Ratio SU-8 Nanopillars

In this paper, label-free biosensing for antibody screening by periodic lattices of high-aspect ratio SU-8 nano-pillars (BICELLs) is presented. As a demonstration, the determination of anti-gestrinone antibodies from whole rabbit serum is carried out, and for the first time, the dissociation constant (KD = 6 nM) of antigen-antibody recognition process is calculated using this sensing system. After gestrinone antigen immobilization on the BICELLs, the immunorecognition was performed. The cells were interrogated vertically by using micron spot size Fourier transform visible and IR spectrometry (FT-VIS-IR), and the dip wavenumber shift was monitored. The biosensing assay exhibited good reproducibility and sensitivity (LOD = 0.75 ng/mL).Ortega Higueruelo, FJ.; Bañuls Polo, MJ.; Sanza, FJ.; Casquel, R.; Laguna, MF.; Holgado, M.; López-Romero, D.... (2012). Biomolecular Interaction Analysis of Gestrinone-anti-Gestrinone Using Arrays of High Aspect Ratio SU-8 Nanopillars. 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Evaluation of grape pomace from red wine by-product as feed for sheep

9 páginas, 4 tablas, 3 figuras.This work aimed to study the chemical composition and in vitro digestibility of seeds and pulp from grape pomace. In sacco degradability, ruminal fermentation of grape pomace fractions and plasma lipid peroxidation were also studied in sheep fed with or without grape pomace. RESULTS: Seed and pulp fractions of grape pomace had different values for cell walls (523 vs 243 g kg dry matter (DM)), crude protein (CP, 104 vs 138 g kg DM), ether extract (EE, 99.0 vs 31.7 g kg DM), polyunsaturated fatty acids (PUFA, 69.6 vs 53.3%) and extractable polyphenols (55.0 vs 32.1 g kg DM). The in vitro true digestibility, DM in sacco degradability and CP degradability of seeds and pulp were also different (0.51 vs 0.82, 0.30 vs 0.45 and 0.66 vs 0.39 respectively). The ammonia-N concentration and total volatile fatty acids (VFA) in ruminal liquid were significantly lower and plasma lipid peroxidation was also numerically lower in sheep that consumed grape pomace. CONCLUSION: The nutritive value of grape pomace varies depending on the proportion of seeds and pulp. The interest of this by-product in sheep feeding could be related to its polyphenol and PUFA content, which could improve meat and milk quality. © 2016 Society of Chemical Industry.This work was subsidized by INIA (RTA2010-0068-C02) andthe Consejería de Educación de la Junta de Castilla y León(VA196A11-2). Cristina Guerra-Rivas was supported by an FPUgrant (FPU AP-2010-0571) from the Spanish Ministry of Education.We would also like to thank Escuela de Capacitación Agraria deViñalta (Junta de Castilla y León) for the facilities and the animalsused in this study.Peer Reviewe

Ratiometric Oxygen Imaging to Predict Oxygen Diffusivity in Oak Wood During Red Wine Barrel Aging

Producción CientíficaAbstract In this work, we present a high-resolution oxygen imaging approach to study the two-dimensional oxygen dis- tribution inside an oak stave in contact with wine and that applies the series resistance model to explain the dynamic evolution of oak wood oxygen transfer rate (OTR). Oxygen flux throughout the oak stave has been studied by considering the wood as a permeable membrane with moisture content (MC) in a decreasing gradient from the wine-contacting side of the oak stave to the side in contact with atmospheric air in cellar conditions. The presence of different levels of liquid across the thickness of the wet stave modifies the oxygen diffusion flux, as the diffusion coefficient of oxygen in water is four orders of magnitude lower than in air. The stave resem- bles a multilayered membrane, where wood with an MC over the fiber saturation point represents a distinct layer. To that end, three simultaneous measurements were made, namely the MC profile of the wood within the thickness of the stave at different liquid-wood contact times, the OTR of the stave at those times, and finally the oxygen concentration profile with- in the thickness of the stave using planar optical sensors, a color camera, and ratiometric image analysis. The results show heat flux and oxygen flux that is analogous to that in a multilayer.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA124U14

Regulation of androgen receptor activity by transient interactions of its transactivation domain with general transcription regulators

The androgen receptor is a transcription factor that plays a key role in the development of prostate cancer, and its interactions with general transcription regulators are therefore of potential therapeutic interest. The mechanistic basis of these interactions is poorly understood due to the intrinsically disordered nature of the transactivation domain of the androgen receptor and the generally transient nature of the protein-protein interactions that trigger transcription. Here, we identify a motif of the transactivation domain that contributes to transcriptional activity by recruiting the C-terminal domain of subunit 1 of the general transcription regulator TFIIF. These findings provide molecular insights into the regulation of androgen receptor function and suggest strategies for treating castration-resistant prostate cancer.This work was supported by IRB, ICREA (X.S.), Obra Social “la Caixa” (E.D.M., E.S., and X.S.), MINECO (BIO2012-31043 and BIO2015-70092-R to X.S., BIO2014-53095-P to G.D.F.), Marató de TV3 (102030 to X.S. and 102031 to E.E.-P), the COFUND program of the European Commission (C.D.S.), the European Research Council (CONCERT, contract number 648201 to X.S.), the Ramón y Cajal program of MICINN (RYC-2011-07873 to C.W.B.), the Serra Hunter Program (E.E.-P.), AGAUR (SGR-2014-56RR14 to E.E.-P), and FEDER (G.D.F.). I.H. was supported by funding from the Chief Scientist's Office of the Scottish Government (ETM-258, ETM-382). IRB Barcelona is the recipient of a Severo Ochoa Award of Excellence from MINECO (Government of Spain)

Author Correction: Hsp70 and Hsp40 inhibit an inter-domain interaction necessary for transcriptional activity in the androgen receptor.

An amendment to this paper has been published and can be accessed via a link at the top of the paper