Retinoic-Acid-Induced Downregulation of the 67 KDa Laminin Receptor Correlates with Reduced Biological Aggressiveness of Human Neuroblastoma Cells

16 pages (217-232), 6 figuresThe authors are indebted to Dr. S. Menard (Milan, Italy) for the gift of the antibody against 37LRP. C. M. R. L. was supported by Programa de Personal Técnico de Apoyo (PTA-2003-02-00207; Ministry of Education and Science, Spain). This work was supported by grants from the Spanish former Ministry of Education and Science and Ministry of Science and Innovation (SAF2003-00311, SAF2006–00647 and SAF2007–60780) and Generalitat Valenciana (GRUPOS 03/15 and ACOMP 09/212) (to D. B.) , and Instituto de Salud Carlos III (RD20-102 to S. N.).Peer reviewe

Biocatalytic Behaviour of Immobilized Rhizopus oryzae Lipase in the 1,3-Selective Ethanolysis of Sunflower Oil to Obtain a Biofuel Similar to Biodiesel

A new biofuel similar to biodiesel was obtained in the 1,3-selective transesterification reaction of sunflower oil with ethanol using as biocatalyst a Rhizopus oryzae lipase (ROL) immobilized on Sepiolite, an inorganic support. The studied lipase was a low cost powdered enzyme preparation, Biolipase-R, from Biocon-Spain, a multipurpose additive used in food industry. In this respect, it is developed a study to optimize the immobilization procedure of these lipases on Sepiolite. Covalent immobilization was achieved by the development of an inorganic-organic hybrid linker formed by a functionalized hydrocarbon chain with a pendant benzaldehyde, bonded to the AlPO4 support surface. Thus, the covalent immobilization of lipases on amorphous AlPO4/sepiolite (20/80 wt %) support was evaluated by using two different linkers (p-hydroxybenzaldehyde and benzylamine-terephthalic aldehyde, respectively). Besides, the catalytic behavior of lipases after physical adsorption on the demineralized sepiolite was also evaluated. Obtained results indicated that covalent immobilization with the p-hydroxybenzaldehyde linker gave the best biocatalytic behavior. Thus, this covalently immobilized lipase showed a remarkable stability as well as an excellent capacity of reutilization (more than five successive reuses) without a significant loss of its initial catalytic activity. This could allow a more efficient fabrication of biodiesel minimizing the glycerol waste productio

A Biofuel Similar to Biodiesel Obtained by Using a Lipase from Rhizopus oryzae, Optimized by Response Surface Methodology

A new biodiesel-like biofuel is obtained by the enzymatic ethanolysis reaction of sunflower oil with ethanol, in free solvent media, by using BIOLIPASE-R, a multipurpose alimentary additive from Biocon®-Spain that is a low cost lipase from a strain of Rhizopus oryzae. This biofuel is composed by two parts of fatty acid ethyl esters (FAEE) and one of monoglyceride (MG), which in this form integrates glycerol, through the application of the 1,3-selective lipases. Thus, this process minimizes waste generation and maximizes the efficiency of the process because no residual glycerol is produced. Response surface methodology (RSM) is employed to evaluate the main reaction parameters (reaction temperature, oil/ethanol ratio and pH) on the sunflower oil conversion. Water content and amount of lipase were also previously investigated. Regarding the results, we found that it operates optimally with a water content of the reaction medium of 0.15%, 0.05%–0.1% lipase by weight relative to the weight of oil used, 20 °C, volume ratio (mL/mL) oil/ethanol 12/3.5 and pH 12 (by addition of 50 μL of 10 N NaOH solution). These results have proven a very good efficiency of the biocatalyst in the studied selective process

Low-frequency radio observations of the MGRO J2019+37 Complex

We present here a preliminary account of the results of a wide-field mosaic obtained at 610 MHz (49 cm) with the Giant Metre-wave Radio Telescope (GMRT) in India covering the field of the unidentified TeV source MGRO J2019+37. A catalogue of all radio sources detected has been created including both compact and extended objects. Their observational properties are described and presented. We draw the attention to some peculiar objects inside the ˜1° uncertainty region of the TeV emission. The possible connection of these sources with the MILAGRO γ-ray emission will be assessed in future work.Fil: Sánchez Sutil, Juan R. . Universidad de Jaén; EspañaFil: Paredes, Josep M.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Moldón, J.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Zabalza, V.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Bordas, P.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Ribó, M.. Universitat de Barcelona. Departament d’Astronomia i Meteorologia and Institut de Ciències del Cosmos; EspañaFil: Martí, Josep. Universidad de Jaén; EspañaFil: Muñoz Arjonilla, Alvaro J.. Universidad de Jaén; EspañaFil: Luque Escamilla, Pedro L.. Universidad de Jaén; EspañaFil: Ishwara Chandra, C. H.. NCRA. TIFR; IndiaFil: Peracaula, Marta. Universidad de Girona; EspañaFil: Bosch Ramon, Valenti. Max Planck Institut Fur Kernphysik, Heidelberg; AlemaniaFil: Romero, Gustavo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto Argentino de Radioastronomia (i); Argentin

Biodiversity of Gastropod in the Southeastern Gulf of California, Mexico

Currently, studying the environment is important because of the phenomena that take place on the earth every day. That is why it is a priority to carry out studies that relate environmental changes to the biology of organisms. This allows us to know the interactions with the environment, and in this way solve, reduce or prevent ecological and economic problems, if they are organisms with a commercial value. The objective of this investigation is to determine ecological parameters of the gastropod community from the intertidal zone on five islands from the Gulf of California, México, to model the diversity, distribution and abundance of malacological fauna. We considered to evaluate the Shannon-Wiener diversity (H′), Pielou’s of evenness (J) and the Margalef species richness indexes, in order to evaluate through an analysis from biotic and abiotic factors, the species status that was collected from the exposed and non-exposed zone tidal. The generated data were contemplated from a year-based biodiversity project (2016–2017) on the following islands: Patos, Bledos, Bleditos, Tunosa, and Mazocahui which belong to the Ohuira lagoon in Ahome, Sinaloa, southeast of the Gulf of California, México. Likewise a status about the importance of gastropods is mentioned for the study area

Antimicrobial Activity of a Cationic Guanidine Compound against Two Pathogenic Oral Bacteria

This study evaluated the potential antimicrobial properties of a polyguanidine (CatDex) on two oral bacteria. Chlorhexidine gluconate 134

Molecular Binding Mechanism of TtgR Repressor to Antibiotics and Antimicrobials

A disturbing phenomenon in contemporary medicine is the prevalence of multidrug-resistant pathogenic bacteria. Efflux pumps contribute strongly to this antimicrobial drug resistance, which leads to the subsequent failure of clinical treatments. The TtgR protein of Pseudomonas putida is a HTH-type transcriptional repressor that controls expression of the TtgABC efflux pump, which is the main contributor to resistance against several antimicrobials and toxic compounds in this microbe. One of the main strategies to modulate the bacterial resistance is the rational modification of the ligand binding target site. We report the design and characterization of four mutants-TtgRS77A, TtgRE78A, TtgRN110A and TtgRH114A - at the active ligand binding site. The biophysical characterization of the mutants, in the presence and in the absence of different antimicrobials, revealed that TtgRN110A is the variant with highest thermal stability, under any of the experimental conditions tested. EMSA experiments also showed a different dissociation pattern from the operator for TtgRN110A, in the presence of several antimicrobials, making it a key residue in the TtgR protein repression mechanism of the TtgABC efflux pump. We found that TtgRE78A stability is the most affected upon effector binding. We also probe that one mutation at the C-terminal half of helix-α4, TtgRS77A, provokes a severe protein structure distortion, demonstrating the important role of this residue in the overall protein structure and on the ligand binding site. The data provide new information and deepen the understanding of the TtgR-effector binding mechanism and consequently the TtgABC efflux pump regulation mechanism in Pseudomonas putida.This work was supported by Spanish Ministry of Economy and Competitiveness, National programme for Recruitment and Incorporation of Human Resources, Subprogramme: Ramon y Cajal RYC-2009-04570 and grant P11-CVI-7391 from Junta de Andalucía and EFDR (European Regional Development Fund)