17 research outputs found

    Effect of Poly(Oxanorbonene)- and Poly(Methacrylate)-Based Polyzwitterionic Surface Coatings on Cell Adhesion and Gene Expression of Human Keratinocytes

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    Polyzwitterions are generally known for their anti-adhesive properties, including resistance to protein and cell adhesion, and overall high bio-inertness. Yet there are a few polyzwitterions to which mammalian cells do adhere. To understand the structural features of this behavior, a panel of polyzwitterions with different functional groups and overall degrees of hydrophobicity is analyzed here, and their physical and biological properties are correlated to these structural differences. Cell adhesion is focused on, which is the basic requirement for cell viability, proliferation, and growth. With the here presented polyzwitterion panel, three different types of cell-surface interactions are observed: adhesion, slight attachment, and cell repellency. Using immunofluorescence methods, it is found that human keratinocytes (HaCaT) form focal adhesions on the cell-adhesive polyzwitterions, but not on the sample that has only slight cell attachment. Gene expression analysis indicates that HaCaT cells cultivated in the presence of a non-adhesive polyzwitterion have up-regulated inflammatory and apoptosis-related cell signaling pathways, while the gene expression of HaCaT cells grown on a cell-adhesive polyzwitterion does not differ from the gene expression of the growth control, and thus can be defined as fully cell-compatible

    re-habitar El Carmen : Un proyecto sobre patrimonio contemporáneo

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    El proyecto _re-HABITAR suponía para el propio proceder de la institución un avance más allá del reconocimiento, registro, inventario o protección patrimonial de la arquitectura del siglo XX y del Movimiento Moderno para posicionarse en la acción preventiva y conservativa de ese legado contemporáneo. Para ello, la praxis patrimonial se aferraba a un modelo: el de la vivienda social en España en la segunda mitad del siglo XX; a un caso concreto: el de la barriada de Nuestra Señora del Carmen (Recasens Méndez-Queipo de Llano, 1958); y a un requisito fundamental: analizar un objeto vivo y en uso, aún con la presencia de quienes lo vivieron y usaron desde su origen

    Spacer Effects in Sulfo‐ and Sulfabetaine Polymers on Their Resistance against Proteins and Pathogenic Bacteria

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    Abstract The resistance of zwitterionic polymer coatings against the adsorption of proteins and the attachment of pathogenic bacteria is influenced by the precise molecular architecture of the polymers. Two until now rarely studied molecular variables in this context are side chain spacer groups separating the zwitterionic moieties from the polymer backbone and spacer groups separating the cationic and anionic groups within the zwitterionic moiety. Therefore, a set of six poly(sulfobetaine)s and poly(sulfabetaine)s is prepared, in which these spacer groups are systematically varied, incorporating ethylene, propylene, and undecylene side chain spacers, as well as ethylene, propylene, and butylene inter‐charge spacers, and their effects on the antifouling behavior are explored. Hence, the corresponding zwitterionic methacrylates are copolymerized with a photo‐reactive methacrylate bearing a benzophenone moiety. All zwitterionic coatings reveal hydrophilic properties when immersed in water and those with relatively short spacers show effective suppression of non‐specific protein adsorption. Polysulfobetaines outperform the polysulfabetaine ones in terms of resistance against adhesion of bacteria. The overall best fouling protection is observed for the polysulfobetaine bearing a propylene side chain spacer, which coincides with their relatively highest water solubility. The results corroborate previous findings that even apparently minor molecular changes of polyzwitterions can strongly affect their antifouling performance

    Tumor of the epididymis: an uncommon presentation of disseminated coccidioidomycosis

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    Coccidioidomycosis is an endemic disease of arid regions in the Western hemisphere. Its clinical presentation varies from asymptomatic nodules on chest x-rays to disseminated disease. We present the case of a 48-year-old man with a hard and heterogeneous tumor in the posterior aspect of the right testis. Color flow doppler testicular ultrasonography was performed and two nodular masses in the tail of the right epididymis were identified. An epididymectomy was performed and histopathological examination revealed coccidioidomycosis. After diagnosis, the patient was successfully treated with fluconazol

    Antimicrobial Properties of Copper Nanoparticles and Amino Acid Chelated Copper Nanoparticles Produced by Using a Soya Extract

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    This paper reports a comparison of the antibacterial properties of copper-amino acids chelates and copper nanoparticles against Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. These copper-amino acids chelates were synthesized by using a soybean aqueous extract and copper nanoparticles were produced using as a starting material the copper-amino acids chelates species. The antibacterial activity of the samples was evaluated by using the standard microdilution method (CLSI M100-S25 January 2015). In the antibacterial activity assays copper ions and copper-EDTA chelates were included as references, so that copper-amino acids chelates can be particularly suitable for acting as an antibacterial agent, so they are excellent candidates for specific applications. Additionally, to confirm the antimicrobial mechanism on bacterial cells, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) was carried out. A significant enhanced antimicrobial activity and a specific strain were found for copper chelates over E. faecalis. Its results would eventually lead to better utilization of copper-amino acids chelate for specific application where copper nanoparticles can be not used

    Spacer effects in sulfo- and sulfabetaine polymers on their resistance against proteins and pathogenic bacteria

    No full text
    The resistance of zwitterionic polymer coatings against the adsorption of proteins and the attachment of pathogenic bacteria is influenced by the precise molecular architecture of the polymers. Two until now rarely studied molecular variables in this context are side chain spacer groups separating the zwitterionic moieties from the polymer backbone and spacer groups separating the cationic and anionic groups within the zwitterionic moiety. Therefore, a set of six poly(sulfobetaine)s and poly(sulfabetaine)s is prepared, in which these spacer groups are systematically varied, incorporating ethylene, propylene, and undecylene side chain spacers, as well as ethylene, propylene, and butylene inter-charge spacers, and their effects on the antifouling behavior are explored. Hence, the corresponding zwitterionic methacrylates are copolymerized with a photo-reactive methacrylate bearing a benzophenone moiety. All zwitterionic coatings reveal hydrophilic properties when immersed in water and those with relatively short spacers show effective suppression of non-specific protein adsorption. Polysulfobetaines outperform the polysulfabetaine ones in terms of resistance against adhesion of bacteria. The overall best fouling protection is observed for the polysulfobetaine bearing a propylene side chain spacer, which coincides with their relatively highest water solubility. The results corroborate previous findings that even apparently minor molecular changes of polyzwitterions can strongly affect their antifouling performance

    Theoretical Prediction of Structures, Vibrational Circular Dichroism, and Infrared Spectra of Chiral Be4B8 Cluster at Different Temperatures

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    Lowest-energy structures, the distribution of isomers, and their molecular properties depend significantly on geometry and temperature. Total energy computations using DFT methodology are typically carried out at a temperature of zero K; thereby, entropic contributions to the total energy are neglected, even though functional materials work at finite temperatures. In the present study, the probability of the occurrence of one particular Be4B8 isomer at temperature T is estimated by employing Gibbs free energy computed within the framework of quantum statistical mechanics and nanothermodynamics. To identify a list of all possible low-energy chiral and achiral structures, an exhaustive and efficient exploration of the potential/free energy surfaces is carried out using a multi-level multistep global genetic algorithm search coupled with DFT. In addition, we discuss the energetic ordering of structures computed at the DFT level against single-point energy calculations at the CCSD(T) level of theory. The total VCD/IR spectra as a function of temperature are computed using each isomer’s probability of occurrence in a Boltzmann-weighted superposition of each isomer’s spectrum. Additionally, we present chemical bonding analysis using the adaptive natural density partitioning method in the chiral putative global minimum. The transition state structures and the enantiomer–enantiomer and enantiomer–achiral activation energies as a function of temperature evidence that a change from an endergonic to an exergonic type of reaction occurs at a temperature of 739 K

    Effects of Temperature on Enantiomerization Energy and Distribution of Isomers in the Chiral Cu13 Cluster

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    In this study, we report the lowest energy structure of bare Cu13 nanoclusters as a pair of enantiomers at room temperature. Moreover, we compute the enantiomerization energy for the interconversion from minus to plus structures in the chiral putative global minimum for temperatures ranging from 20 to 1300 K. Additionally, employing nanothermodynamics, we compute the probabilities of occurrence for each particular isomer as a function of temperature. To achieve that, we explore the free energy surface of the Cu13 cluster, employing a genetic algorithm coupled with density functional theory. Moreover, we discuss the energetic ordering of isomers computed with various density functionals. Based on the computed thermal population, our results show that the chiral putative global minimum strongly dominates at room temperature

    Fecal Gluten Peptides Reveal Limitations of Serological Tests and Food Questionnaires for Monitoring Gluten-Free Diet in Celiac Disease Patients.

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    JOURNAL ARTICLE;OBJECTIVES Treatment for celiac disease (CD) is a lifelong strict gluten-free diet (GFD). Patients should be followed-up with dietary interviews and serology as CD markers to ensure adherence to the diet. However, none of these methods offer an accurate measure of dietary compliance. Our aim was to evaluate the measurement of gluten immunogenic peptides (GIP) in stools as a marker of GFD adherence in CD patients and compare it with traditional methods of GFD monitoring. METHODS We performed a prospective, nonrandomized, multicenter study including 188 CD patients on GFD and 84 healthy controls. Subjects were given a dietary questionnaire and fecal GIP quantified by enzyme-linked immunosorbent assay (ELISA). Serological anti-tissue transglutaminase (anti-tTG) IgA and anti-deamidated gliadin peptide (anti-DGP) IgA antibodies were measured simultaneously. RESULTS Of the 188 celiac patients, 56 (29.8%) had detectable GIP levels in stools. There was significant association between age and GIP in stools that revealed increasing dietary transgressions with advancing age (39.2% in subjects ≥13 years old) and with gender in certain age groups (60% in men ≥13 years old). No association was found between fecal GIP and dietary questionnaire or anti-tTG antibodies. However, association was detected between GIP and anti-DGP antibodies, although 46 of the 53 GIP stool-positive patients were negative for anti-DGP. CONCLUSIONS Detection of gluten peptides in stools reveals limitations of traditional methods for monitoring GFD in celiac patients. The GIP ELISA enables direct and quantitative assessment of gluten exposure early after ingestion and could aid in the diagnosis and clinical management of nonresponsive CD and refractory CD. Trial registration number NCT02711397.Th is work was supported by grants from Ministerio de Ciencia e Innovación and FEDER funds (DELIAC, IPT-2011-0952-900000), and Corporación Tecnológica de Andalucía (SINGLUCHECK, 1737/0118).Ye
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