Organocatalyzed Enantioselective Aldol and Henry Reactions Starting from Benzylic Alcohols

Pioneering aldol and Henry reactions starting from benzylic-type alcohols are described. The aldol reaction has been successfully performed following a one-pot strategy starting from alcohols, while the Henry reaction has been carried out following a sequential protocol for the first time. In both processes, enantiomerically enriched products were obtained with good yields and high enantioselectivities. We have also demonstrated that in reactions sensitive to small amounts of acid the use of alcohols instead of aldehydes could be a good solution for improving the results of these reactions. (Figure presented.)

Osteonecrosis de los maxilares asociada a bifosfonatos: revisión sistemática

En los últimos años se ha descrito una nueva complicación en la terapia con bifosfonatos: la osteonecrosis de los maxilares. Esta complicación no había sido detectada en los ensayos clínicos previos. En esta revisión sistemática de 340 casos, los pacientes afectados presentan como diagnóstico primario principalmente: mieloma múltiple (51,2%), cáncer de mama (31,4%), cáncer de próstata (7,1%) y osteoporosis (4,1%). La mandíbula resulta más afectada que el maxilar, con el 59,1%. La relación entre género femenino y masculino es de 2:2,6. El pamidronato es el bifosfonato más asociado a los casos de osteonecrosis (35,3%). Los factores de riesgos desencadenantes incluyen: exposición a bifosfonatos, infecciones orales, traumas, procedimientos quirúrgicos orales previos y terapias contra el cáncer (quimioterapia, corticoides y otros agentes citostáticos). La alteración en el equilibrio óseo, factores antiangiogénicos, inhibición en el ciclo celular de los queratinocitos y mecanismos osteolíticos generados en la infección podrían explicar la etiopatogenia en el desarrollo de esta complicación

Functionalization of p-activated alcohols by trapping carbocations in pure water under smooth conditions

Acetic acid as catalyst in pure water was found to be an excellent reaction medium for the direct dehydrative functionalization of p-activated alcohols using a wide variety of interesting C-, P-, and S-centered nucleophiles, such as indoles, pyrrole, anilines, 1, 3-dicarbonyl compounds, diphenyl phosphite and pyridine-2-thiol. The smooth reaction conditions, along with high yields, short reaction times, clean reaction crudes, an easy product isolation procedure, plus the reusability of the catalyst and the use of no excess of nucleophiles, make this approach an atom economical, green and appealing method to efficiently trap carbocations in pure water, leading to new Csp3 X bonds (X = Csp2, Csp3, P and S)

The detection of neutron clusters

A new approach to the production and detection of bound neutron clusters is presented. The technique is based on the breakup of beams of very neutron-rich nuclei and the subsequent detection of the recoiling proton in a liquid scintillator. The method has been tested in the breakup of 11Li, 14Be and 15B beams by a C target. Some 6 events were observed that exhibit the characteristics of a multineutron cluster liberated in the breakup of 14Be, most probably in the channel 10Be+4n. The various backgrounds that may mimic such a signal are discussed in detail.Comment: 11 pages, 12 figures, LPCC 01-1

Gel-Dispersed Nanostructures Lipid Carriers Loading Thymol Designed for Dermal Pathologies

Purpose: Acne vulgaris is one of the most prevalent dermal disorders affecting skin health and appearance. To date, there is no effective cure for this pathology, and the majority of marketed formulations eliminate both healthy and pathological microbiota. Therefore, hereby we propose the encapsulation of an antimicrobial natural compound (thymol) loaded into lipid nanostructured systems to be topically used against acne.Methods: To address this issue, nanostructured lipid carriers (NLC) capable of encapsulating thymol, a natural compound used for the treatment of acne vulgaris, were developed either using ultrasonication probe or high-pressure homogenization and optimized using 22-star factorial design by analyzing the effect of NLC composition on their physicochemical parameters. These NLC were optimized using a design of experiments approach and were characterized using different physicochemical techniques. Moreover, short-term stability and cell viability using HaCat cells were assessed. Antimicrobial efficacy of the developed NLC was assessed in vitro and ex vivo.Results: NLC encapsulating thymol were developed and optimized and demonstrated a prolonged thymol release. The formulation was dispersed in gels and a screening of several gels was carried out by studying their rheological properties and their skin retention abilities. From them, carbomer demonstrated the capacity to be highly retained in skin tissues, specifically in the epidermis and dermis layers. Moreover, antimicrobial assays against healthy and pathological skin pathogens demonstrated the therapeutic efficacy of thymol-loaded NLC gelling systems since NLC are more efficient in slowly reducing C. acnes viability, but they possess lower antimicrobial activity against S. epidermidis, compared to free thymol.Conclusion: Thymol was successfully loaded into NLC and dispersed in gelling systems, demonstrating that it is a suitable candidate for topical administration against acne vulgaris by eradicating pathogenic bacteria while preserving the healthy skin microbiome.</p

Síntesis del estudio de los suelos de Les Garriges Lleida

[15] Pags.- 3 Fots.La presente publicación trata de dar a conocer de modo sumamente resumido un amplio Estudio de los Suelos de Les Garrigues. Dicho Estudio ha sido dirigido por el Departamento de Edafología y Climatología (x) de la Escuela Técnica Supe­rior de Ingenieros Agrónomos de Lleida, perteneciente a la Universidad Politécnica de Barcelona; en equipo con el Departamento de Geomorfología y Tectónica (xx) de la Universidad de Barcelona y con el Instituto Jaime Almera de Investigaciones Geológicas del Consejo Superior de Investigaciones Científicas (xxx) (Barcelona). El trabajo se estructura básicamente en dos partes, la primera se dedica a la FI­SIOGRAFIA y en ella se indica la localización y límites de la zona estudiada. Se ca­racteriza el CLIMA, elaborando los datos meteorológicos suministrados por los ob­servatorios de la comarca y que cuentan con series de como mínimo diez años. Las características climáticas estudiadas son el régimen termométrico, de heladas, el pluviométrico con sus correspondientes análisis estadísticos, la torrencialidad, la evotranspiración potencial, el balance hídrico y los índices y clasificaciones climáti­cas, que permiten sintetizar el clima de Les Garrigues. Se estudia la GEOLOGIA, tanto lo referente a la litología de los materiales, la tectónica, la geomorfología, la dinámica actual, como a la hidrogeología. La segunda parte trata del ESTUDIO DE LOS SUELOS. De cada punto pros­pectado se describen las propiedades del suelo y su caracterización analítica. Todo ello suministra los datos de base para estudiar la génesis, discutir la clasificación, y deducir los factores limitantes y la idoneidad de cada categoría de suelos para deter­minados usos. Un apartado dedicado al «USO DEL SUELO» cierra esta segunda parte. En él se profundiza en aspectos aplicados, destacando el papel de los factores limitantes del uso del suelo; se evalua el estado actual de los niveles de fertilidad de los suelos y se dan algunas orientaciones para mejorar los programas de abonado. Por último, se tratan aspectos relacionados con la ordenación del territorio, a un nivel muy ge­neral.Peer reviewe

Three-body correlations in Borromean halo nuclei

Three-body correlations in the dissociation of two-neutron halo nuclei are explored using a technique based on intensity interferometry and Dalitz plots. This provides for the combined treatment of both the n-n and core-n interactions in the exit channel. As an example, the breakup of 14Be into 12Be+n+n by Pb and C targets has been analysed and the halo n-n separation extracted. A finite delay between the emission of the neutrons in the reaction on the C target was observed and is attributed to 13Be resonances populated in sequential breakup.Comment: 5 pages, 4 figures, submitted to PR

A Putative Plant Aminophospholipid Flippase, the Arabidopsis P4 ATPase ALA1, Localizes to the Plasma Membrane following Association with a β-Subunit

Plasma membranes in eukaryotic cells display asymmetric lipid distributions with aminophospholipids concentrated in the inner leaflet and sphingolipids in the outer leaflet. This unequal distribution of lipids between leaflets is, amongst several proposed functions, hypothesized to be a prerequisite for endocytosis. P4 ATPases, belonging to the P-type ATPase superfamily of pumps, are involved in establishing lipid asymmetry across plasma membranes, but P4 ATPases have not been identified in plant plasma membranes. Here we report that the plant P4 ATPase ALA1, which previously has been connected with cold tolerance of Arabidopsis thaliana, is targeted to the plasma membrane and does so following association in the endoplasmic reticulum with an ALIS protein β-subunit