249 research outputs found

    Hydrogen-Bonding Organocatalysis Enabled Photocatalytic Intramolecular [2+2]-Cycloaddition Reaction

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    The combination of organocatalytic activation and photocatalysis for enabling the intramolecular [2+2]‐cycloaddition of enone‐ene substrates bearing one Lewis base binding site is reported. While in a variety of solvents a poor conversion or no reaction takes place in the absence of a hydrogen bonding catalyst, the corresponding ring‐fused cyclobutane products could be built in moderate to good yields using a synergistic dual iridium‐urea co‐catalytic system. Control and mechanistic studies supported the postulated interaction between the organocatalyst and the substrate, which proved essential for an efficient energy transfer from the photosensitizer

    Transparency in informative content : an analysis of methods in Spanish data journalism (2019-2022)

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    La crisis de confianza en el periodismo ha aumentado las esperanzas depositadas en la transparencia interna de los contenidos. Las posibilidades técnicas del periodismo de datos y su vinculación con las ciencias sociales suponen una oportunidad para poner en práctica estos valores de apertura y trazabilidad. Esta investigación se centra en las piezas que, en el día a día (no proyectos especiales), produjeron los medios españoles con unidades de datos (n = 10) entre enero de 2019 y abril de 2022. A través de un análisis de contenido cuantitativo y cualitativo de una muestra aleatoria de artículos (n = 62), este estudio explora la transparencia de las fuentes y el uso de la sección específica de metodología. Los resultados revelan un uso desigual y, en muchas ocasiones, poco frecuente de elementos, como la explicación del proceso de investigación o la posibilidad de descarga de datos. Se observa un mayor desarrollo en los medios nativos digitales y en los proyectos pequeños y especializados, con algunas excepciones. Se constata así la reticencia de algunos medios a implementar los nuevos «rituales de transparencia» y la mayor importancia de la actitud y la iniciativa individual frente a los recursos de las redacciones. Finalmente, se detecta una influencia ambivalente del COVID-19 en estas prácticas, lo que sugiere la necesidad de fomentar una visión crítica del periodismo de datos y la evolución de la transparencia interna del periodismo.La crisi de confiança en el periodisme ha augmentat les esperances dipositades en la transparència interna dels continguts. Les possibilitats tècniques del periodisme de dades i la seva vinculació amb les ciències socials suposen una oportunitat per posar en pràctica aquests valors d'obertura i traçabilitat. Aquesta recerca se centra en les peces que, en el dia a dia (no projectes especials), van produir els mitjans espanyols amb unitats de dades (n = 10) entre gener de 2019 i abril de 2022. A través d'una anàlisi de contingut quantitatiu i qualitatiu d'una mostra aleatòria d'articles (n = 62), aquest estudi explora la transparència de les fonts i l'ús de la secció específica de metodologia. Els resultats revelen un ús desigual i moltes vegades poc freqüent d'elements, com l'explicació del procés de recerca o la possibilitat de descàrrega de dades. S'observa un desenvolupament més gran en els mitjans nadius digitals i en els projectes petits i especialitzats, amb unes quantes excepcions. Es constata així la reticència d'alguns mitjans a implementar els nous «rituals de transparència » i la major importància de l'actitud i la iniciativa individual enfront dels recursos de les redaccions. Finalment, es detecta una influència ambivalent de l COVID-19 en aquestes pràctiques, la qual cosa suggereix la necessitat de fomentar una visió crítica del periodisme de dades i l'evolució de la transparència interna del periodisme.The crisis of confidence in journalism has increased hopes of internal transparency. The technical possibilities of data journalism and its background in social sciences support the values of openness and transparency. This study focuses on the daily journalism produced by the data units of the Spanish media (n=10) between January 2019 and April 2022. Through analysis of quantitative and qualitative content of a random sample of articles (n=62), this study explores the transparency of sources and the use of a methodology section. The results reveal an unequal and, on many occasions, infrequent use of elements such as an explanation of the research process or the possibility for data download. A greater use is observed in native online media and small and specialised projects, with certain exceptions, reflecting the reluctance of some media to implement the new "transparency rituals" and the greater importance of attitude and individual initiative rather than resources. Finally, an ambivalent influence of COVID-19 is detected in these practices, which suggest a critical view of data journalism and the evolution of its transparency

    Food and nutrition myths among future secondary school teachers: A problem of trust in inadequate sources of information

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    The Internet and social networks are full of nutrition information, offering people guidance to make healthy eating choices. These sources always present themselves as a gateway to reliable information on healthy eating; however, too often this is not the case. Far from being trustworthy, there are usually plenty of food myths. A food myth is a widespread false belief about food, nutrition, and eating facts that gives rise to certain behaviors, from fashionable trends to diets. Academic training is a valuable tool to combat food myths and the pseudoscience linked to them, but educators must participate in this battle. To test this idea, we analyzed the prevalence of nine highly popular food myths held by 201 secondary school Spanish teachers. The aim was to assess whether expertise in science areas prevents teachers from falling into these food misconceptions. Our study results showed that food myths are held regardless of specialty area. The power of the media in popularizing and spreading nutrition myths among educators may be the cause, even more potent than academic training. We conclude that since scientific knowledge is not enough to erase food myths, we need further actions if we aim to prevent the problems that food myths may cause

    GSE4, a small dyskerin- and GSE24.2-related peptide, induces telomerase activity, cell proliferation and reduces DNA damage, oxidative stress and cell senescence in dyskerin mutant cells

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    Dyskeratosis congenita is an inherited disease caused by mutations in genes coding for telomeric components. It was previously reported that expression of a dyskerin-derived peptide, GSE24.2, increases telomerase activity, regulates gene expression and decreases DNA damage and oxidative stress in dyskeratosis congenita patient cells. The biological activity of short peptides derived from GSE24.2 was tested and one of them, GSE4, that probed to be active, was further characterized in this article. Expression of this eleven amino acids long peptide increased telomerase activity and reduced DNA damage, oxidative stress and cell senescence in dyskerin-mutated cells. GSE4 expression also activated c-myc and TERT promoters and increase of c-myc, TERT and TERC expression. The level of biological activity of GSE4 was similar to that obtained by GSE24.2 expression. Incorporation of a dyskerin nuclear localization signal to GSE24.2 did not change its activity on promoter regulation and DNA damage protection. However, incorporation of a signal that increases the rate of nucleolar localization impaired GSE24.2 activity. Incorporation of the dyskerin nuclear localization signal to GSE4 did not alter its biological activity. Mutation of the Aspartic Acid residue that is conserved in the pseudouridine synthase domain present in GSE4 did not impair its activity, except for the repression of c-myc promoter activity and the decrease of c-myc, TERT and TERC gene expression in dyskerin-mutated cells. These results indicated that GSE4 could be of great therapeutic interest for treatment of dyskeratosis congenita patients.This work was supported by grants PI1401495 (supported by FEDER funds) and ER15PR07ACC114/757 (Fondo de Investigaciones Sanitarias, Instituto de Salud Carlos III. Spain), 201320E075 (Consejo Superior de Investigaciones Científicas) and IPT-2012-0674- 090000 (Ministerio de Economía y Competitividad. Spain). CM-G is supported by the CIBER de Enfermedades Raras.Peer Reviewe

    New data on the turtles from Puerto de la Cadena (Late Miocene of Murcia)

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    La Alberca es un yacimiento paleontológico del Mioceno Superior situado en el área del Puerto de la Cadena (Murcia, España). Allí se ha identificado una fauna de mamíferos relativamente diversa. No obstante, la información referente a sus tortugas era, hasta ahora, muy limitada. En otros yacimientos del Puerto de la cadena se han identificado abundantes restos de tortugas, asignados a Testudinidae. El estudio de las tortugas de La Alberca permite identificar un miembro de Testudinidae de gran tamaño, asignado preliminarmente a Cheirogaster cf. bolivari, y una tortuga acuática, assignada a Trionychinae. Este último hallazgo aumenta el rango de distribución estratigráfica de este grupo de quelonios en la Península Ibérica. Además, constituye la primera referencia a Trionychinae en la mitad sur de España. La revisión de material inédito permite identificar la presencia de Trionychinae en otros afloramientos del Puerto de la CadenaLa Alberca is a fossil site of the Late Miocene of the area of Puerto de la Cadena (Murcia, Spain). A mammalian fauna with relatively high diversity has been identified there. However, the information about the turtles was, until now, very limited. Abundant turtles, assigned to Testudinidae, have been recognized in other sites of Puerto de la Cadena. The study of the turtles from La Alberca allows to identify a large taxon of testudinid turtle, assigned to Cheirogaster cf. bolivari, and a aquatic turtle, assigned to Trionychinae. This finding broadens the stratigraphic distribution of the group in the Iberian Peninsula. In addition, it constitutes the first reference to Trionychinae in the southern half of Spain. The review of unpublished material allows to identify Trionychinae in other sites of Puerto de la Caden

    Localized leishmaniasis of the oral mucosa. A report of three cases

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    El término leishmaniasis comprende un grupo de enfermedades causadas por diferentes especies de un protozoo llamado Leishmania. La leishmaniasis se produce en todo el mundo, considerándose endémica en 88 países. Existen tres formas clínicas principales de leishmaniasis: leishmaniasis visceral, leishmaniasis cutánea y leishmaniasis mucocutánea. La afectación de la mucosa, de manera exclusiva, por la Leishmania es muy rara. Presentamos una serie de tres casos de leishmaniasis mucosa localizados en la cavidad oral. El hecho de que todos los casos se produjeran en España, área endémica de L infantum, nos hace presuponer que éste fue el agente causal. La única manifestación de enfermedad de leishmaniasis en los casos descritos, fue la aparición de una lesión oral. Se administró tratamiento con antimoniato de meglumina en dos de ellos, respondiendo favorablemente. Uno de los pacientes abandonó el hospital tras el diagnóstico sin recibir tratamiento y se desconoce la evolución. Realizamos también una revisión de la literatura

    Preclinical bioassay of a novel antibacterial mesh for the repair of abdominal hernia defects

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    25 p.Background: In hernia surgery, soaking of meshes in antibiotics before implantation is a prophylactic strategy for minimizing the risk of infection while providing minimal, local, drug doses. This study describes the development and application of an antibacterial mesh coating comprising a carboxymethylcellulose gel loaded with rifampicin in a preclinical model of Staphylococcus aureus and S. epidermidis infection in rabbits. Methods: Antibacterial activity and cytocompatibility (with fibroblasts) of unloaded carboxymethylcellulose gel and 0.13 mg/mL rifampicin-carboxymethylcellulose gel were assessed in vitro. Then, partial abdominal wall defects (5 x 2 cm) were created in New Zealand white rabbits (n = 34), the wound inoculated with 0.25 mL of 106 CFU Staphylococcus aureus/ S. epidermidis (n = 17 each), and the defect then repaired with a lightweight, monofilament, large pore polypropylene mesh either uncoated (n = 3) or coated with carboxymethylcellulose gel (n = 7) or rifampicin-carboxymethylcellulose gel (n = 7). By postoperative day 14, coating performance was evaluated by determining bacterial adhesion (via sonication), host tissue incorporation (via histology), macrophage response via immunostaining), and bloodstream drug diffusion (via high-performance liquid chromatography). Results: In vitro, rifampicin-carboxymethylcellulose gel demonstrated great activity against Staphylococcus aureus/S. epidermidis, while being innocuous for fibroblasts. In vivo, rifampicincarboxymethylcellulose gel-coated implants displayed full bacterial clearance and optimal tissue integration, irrespective of the strain of Staphylococcus. In contrast, uncoated and carboxymethylcellulose gel-coated implants exhibited macro/microscopic signs of infection and impaired tissue integration. Macrophage responses were less in rifampicin-carboxymethylcellulose gel implants than in uncoated mesh (Staphylococcus aureus/S. epidermidis; P < .01) and carboxymethylcellulose gel (S. epidermidis; P < .05) implants. Bloodstream levels of rifampicin were undetectable. Conclusion: Soaking meshes in rifampicin-carboxymethylcellulose gel inhibited effectively the bacterial adhesion to the mesh without compromising the tissue repair. This antibiotic gel constitutes an easy-touse and effective prophylactic strategy that potentially reduce the prevalence of postoperative mesh infectionMinisterio de Ciencia, Innovación y Universidade

    Mesh fixation using a cyanoacrylate applied as a spray improves abdominal wall tissue repair

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    19 p.Background: Tissue adhesives are a feasible option to fix a hernia repair mesh, avoiding tissue trauma of suture fixation. Classically, they are applied in the form of a drop, although novel applications such as spray are emerging. This study compares the use of a new experimental cyanoacrylate (n-butyl) in the form of a spray or drops. Materials and methods: Three study groups of New Zealand White rabbits were established (n ? 6 each) according to the method used to fix a 5 3 cm polypropylene mesh in a partial abdominal wall defect model: control group (polypropylene stitches), adhesive drops group, and adhesive spray group. Morphological, immunohistochemical, and biomechanical strength studies were performed at 14 d postimplant. Collagen 1/3 gene ratio was determined by quantitative reverse transcription polymerase chain reaction. Results: In the drops group, the adhesive obstructed the mesh pores and prevented tissue infiltration at the points of application. When the adhesive was applied as a spray, although more numerous, adhesive deposits were smaller and allowed for better host tissue infiltration into the mesh. The inflammatory response was similar in the adhesive groups and more intense than in the control group. Collagen 1/3 mRNA ratio was significantly higher in the spray than the control group. The mechanical resistance of the meshes was similar in all three groups. * Corresponding author. Department of Surgery, Medical and Social Sciences. Faculty of Medicine and Health Sciences, University of Alcala, Ctra. Madrid-Barcelona, Km 33,600, Alcala de Henares, 28871 Madrid, Spain. Tel.: þ34 91 8854540; fax: þ34 91 8854885. E-mail address: [email protected] (J.M. Bellon). 1 These authors contributed equally to this work. 0022-4804/$ e see front matter ª 2019 Elsevier Inc. All rights reserved. https://doi.org/10.1016/j.jss.2019.08.020 Conclusions: The application of the cyanoacrylate adhesive in the form of spray to fix polypropylene meshes in an animal model had a similar inflammatory response compared with droplet application. Neither application impacted the mechanical strength of the repaired area. An increased in collagen 1/3 ratio was found with cyanoacrylate spray compared with suture, and future studies should focus on this pathway.Ministerio de Economía y Competitivida

    Caracterización de diferentes aceites de girasol ozonizados I. Cambios químicos durante la ozonización

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    Vegetable oils are usually rich in unsaturated fatty acids which are susceptible to oxidation. The oxidation of vegetable oils has been one of the most widely studied fields within lipid chemistry, because it alters their properties and nutritive value, inducing the formation of harmful compounds and off-flavors. Moreover, oxidized vegetable oils display altered physical and chemical properties which are conferred by the newer oxy-genated compounds they contain. This is the case of ozonized oils. Ozone is a powerful oxidizing agent that mainly acts on olefinic compounds which generate ozonides and other peroxidic species that can decompose into carbonilic fragments. The action of the oxidant and the later reactions depend on the chemical environment of the reaction as well as the carbonyl termination products resulting from peroxide cleavage. In recent years, sunflower oils with different fatty acid compositions have been developed by breeding and mutagenesis. They displayed higher contents of oleic, stearic or palmitic acids, which mainly alters their triacylglycerol composi-tion. Therefore, four different sunflower oils, common, high oleic, high stearic-high oleic and high palmitic-high oleic, were oxidized with ozone and the progress of the reaction was monitored by measuring the level of oil peroxygenation and the changes in the oils’ fatty acid compositions. The peroxidated species formed during ozonation were studied by FT-IR spectroscopy. The main conclusions of this work were that ozonation caused linear oxidation rates that were similar in all the oils assayed. The addition of water accelerated oxidation, which tended to occur in linoleic polyunsaturated fatty acid The FT-IR pointed to the presence of ozonide-derived peroxides as the major oxygenated species.Los aceites vegetales son generalmente ricos en ácidos grasos insaturados susceptibles de oxidación. La oxi-dación de aceites vegetales ha sido un campo de estudio intensivo dentro de la química de lípidos ya que este proceso altera sus propiedades y valor nutritivo, induciendo la formación de compuestos perjudiciales y olores y sabores indeseados. Además, los aceites vegetales oxidados muestran propiedades físicas alteradas conferidas por los nuevos compuestos oxigenados que contienen. Este es el caso de los aceites ozonizados. El ozono es un agente oxidante enérgico que actúa sobre los compuestos olefínicos generando ozónidos y otras especies peroxídicas que se descomponen en fragmentos carbonílicos. La acción del oxidante y las reacciones posteriores dependen del entorno químico de la reacción además de los productos carbonílicos de terminación resultante de la rotura de los peróxidos. El aceite de girasol común es rico en oleico y linoleico, susceptibles de ataque oxida-tivo por parte del ozono. En los últimos años, aceites de girasol con composiciones diferentes de ácidos grasos se han desarrollado por selección y mutagénesis. Estos aceites muestran altos contenidos en oleico, esteárico o palmítico, los cuales alteran de manera importante su composición de triglicéridos. Este trabajo es el primero de una serie de dos en los cuales se estudian los cambios físico-químicos que dichos aceites de girasol experimentan durante la ozonización. Así, se oxidaron con ozono cuatro aceites de girasol diferentes, girasol común, alto oleico, alto esteárico-alto oleico y alto palmítico-alto oleico. Se monitorizaron las cantidades absorbidas de ozono, los niveles de peroxidación y los ácidos grasos que experimentaron oxidación. Las especies formadas en el proceso se estudiaron mediante espectroscopía FT-IR. El modo en que la composición de ácidos grasos del aceite afectó a las cinéticas de oxidación y los productos resultantes se comentaron a la vista de los resultados.Consejo Superior de Investigaciones Científicas (CSIC) ICOOPCOOPB2015

    Behaviour at the peritoneal interface of next generation prosthetic materials for hernia repair

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    22 p.Background When using a prosthetic material in hernia repair, the behaviour of the mesh at the peritoneal interface is especially important for implant success. Biomaterials developed for their intraperitoneal placement are known as composites and are made up of two different-structure materials, one is responsible for good integration within host tissue and the other is responsible to make contact with the viscera. This study examines the behaviour at the peritoneal level of two composites, the fully degradable Phasix-ST® and the partially degradable Symbotex®. A polypropylene mesh (Optilene®) served as control. Methods Sequential laparoscopy from 3 to 90 days, in a preclinical model in the New Zealand white rabbit, allowed monitoring adhesion formation. Morphological studies were performed to analyse the neoperitoneum formed in the repair process. Total macrophages were identified by immunohistochemical labelling. To identify the different macrophage phenotypes, complementary DNAs were amplified by qRT-PCR using specific primers for M1 (TNF-?/CXCL9) and M2 (MRC1/IL-10) macrophages. Results The percentage of firm and integrated adhesions remained very high in the control group over time. Both composites showed a significant decrease in adhesions at all study times and in qualitative terms were mainly loose. Significant differences were also observed from 7 days onwards between the two composites, increasing the values in Phasix over time. Neoperitoneum thickness for Phasix was significantly greater than those of the other meshes, showing mature and organized neoformed connective tissue. Immunohistochemically, a significantly higher percentage of macrophages was observed in Symbotex. mRNA expression levels for the M2 repair-type macrophages were highest for Phasix but significant differences only emerged for IL-10. Conclusions Fewer adhesions formed to the Symbotex than Phasix implants. Ninety days after implant, total macrophage counts were significantly higher for Symbotex, yet Phasix showed the greater expression of M2 markers related to the tissue repair process.Ministerio de Economía y Competitivida
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