Self-assembly of Fmoc-tetrapeptides based on the RGDS cell adhesion motif

Self-assembly in aqueous solution has been investigated for two Fmoc [Fmoc ¼ N-(fluorenyl)-9-methoxycarbonyl] tetrapeptides comprising the RGDS cell adhesion motif from fibronectin or the scrambled sequence GRDS. The hydrophobic Fmoc unit confers amphiphilicity on the molecules, and introduces aromatic stacking interactions. Circular dichroism and FTIR spectroscopy show that the self-assembly of both peptides at low concentration is dominated by interactions among Fmoc units, although Fmoc-GRDS shows b-sheet features, at lower concentration than Fmoc-RGDS. Fibre X-ray diffraction indicates b-sheet formation by both peptides at sufficiently high concentration. Strong alignment effects are revealed by linear dichroism experiments for Fmoc-GRDS. Cryo-TEM and smallangle X-ray scattering (SAXS) reveal that both samples form fibrils with a diameter of approximately 10 nm. Both Fmoc-tetrapeptides form self-supporting hydrogels at sufficiently high concentration. Dynamic shear rheometry enabled measurements of the moduli for the Fmoc-GRDS hydrogel, however syneresis was observed for the Fmoc-RGDS hydrogel which was significantly less stable to shear. Molecular dynamics computer simulations were carried out considering parallel and antiparallel b-sheet configurations of systems containing 7 and 21 molecules of Fmoc-RGDS or Fmoc-GRDS, the results being analyzed in terms of both intermolecular structural parameters and energy contributions

¿Le parece bien a nuestros pacientes que su médico de familia interino consolide su empleo en la OPE extraordinaria actualmente en marcha?

IntroducciónLa situación laboral de los médicos de atención primaria puede influir positiva o negativamente en la satisfacción personal de éstos, e indirectamente en la relación médico-paciente. Cabe suponer que un médico de familia con inestabilidad laboral y poco motivado por parte del sistema sanitario tendrá más dificultad para prestar una atención sanitaria de calidad a sus pacientes. Pero ¿qué opinan nuestros pacientes?1-4, ¿les parece bien que su médico tenga estabilidad en su empleo? o ¿prefieren que sea interino para que no se deje llevar por la rutina? Estas cuestiones son las que se intentan aclarar en esta investigación.ObjetivoConocer la opinión de nuestros pacientes acerca de que su médico de familia (MF) interino pase a ser propietario en el proceso extraordinario de consolidación de empleo inciado en diciembre de 2001.DiseñoSe trata de un estudio observacional mediante encuesta en el que no se aplica ninguna intervención.EmplazamientoCentro de salud semiurbano de la periferia de nuestra ciudad.ParticipantesSe seleccionó aleatoriamente al salir de la consulta a 200 pacientes de 3 cupos cuyos MF ocupan plaza de interino y están inmersos en el proceso extraordinario de consolidación de empleo.Mediciones principalesSe les realizó una encuesta autocumplimentada que constaba de 5 afirmaciones para las cuales había 5 opciones de respuesta (muy de acuerdo, de acuerdo, indiferente, en desacuerdo, muy en desacuerdo). Las afirmaciones planteadas a los pacientes eran las siguientes:1.Mi MF estará más tranquilo y será más complaciente si tiene plaza en propiedad, y esto conllevará una mejora de la relación médico-paciente.2.Si mi MF tiene plaza en propiedad, tendrá más tiempo para formación continuada útil, ya que no preparará oposiciones.3.Prefiero que mi MF sea interino, pues así estudiará más.4.Si mi MF es propietario, como es más difícil que le echen de su puesto de trabajo, adquirirá mentalidad de funcionario y nos prestará una atención de peor calidad.5.Un MF debe de trabajar a gusto y estar motivado, por lo que para ello es importante que tenga plaza en propiedad.6.La encuesta fue previamente diseñada por un grupo de 4 médicos de familia siguiendo una técnida Delphi modificada, de la cual surgieron las 5 afirmaciones planteadas.ResultadosEl 72% de los pacientes cree que su MF estará más tranquilo, será más complaciente y mejorará la relación medico-paciente si consolida su plaza en la OPE extraordinaria. Un 42% de los pacientes cree que si un médico tiene plaza en propiedad mejorará en su formación continuada sobre aspectos útiles para su práctica clínica. El 78% de los pacientes opina que si su MF consolida su plaza adquirirá mentalidad de funcionario y prestará una atención de peor calidad. El 62% cree que si su médico tiene plaza en propiedad estará más motivado globalmente y trabajará más a gusto (tabla 1).Discusión y ConclusionesLa última década se ha caracterizado por la escasez de oposiciones para adquirir plaza fija como MF en el sistema nacional de salud. Esto ha llevado a la administración a poner en marcha una oferta pública de empleo (OPE) extraordinaria en diciembre del 2001. En este trabajo, nuestros pacientes nos aportan 2 mensajes principales; en primer lugar, creen que su médico va a trabajar más relajado, mejor y se formará en lo que él considere útil para su práctica clínica diaria si logra consolidar su plaza; en segundo lugar nos advierten del peligro que puede ocasionar que su médico esté tranquilo laboralmente y nos dicen que un medico propietario estudiará menos y además puede adquirir mentalidad de funcionario, con el consiguiente deterioro de la atención que ello conllevaría. En conclusión, nuestros pacientes consideran que si su MF consolida su plaza mejorará la relación médico-paciente, pero adquirirá una mentalidad funcionarial que le hará prestar una atención de inferior calidad.

Distribución por tamaños de la materia particulada en Las Palmas de Gran Canaria

En este trabajo se presenta la distribución por tamaños de la materia particulada (MP)en la ciudad de Las Palmas de Gran Canaria. La experiencia se llevó a cabo entre junio de 2002 y marzo de 2003. A tal efecto se han utilizado captadores de alto volumen equipados con impactadores en cascada, que permiten una separación, en filtros de fibra de vidrio, de la materia recogida en seis fracciones de tamaño. Al final del muestreo se dispuso de 42 muestras válidas para el análisis. La materia particulada se determinó gravimétricamente. Se establecióla distribución de la concentración másica en función de los diámetros de corte. Se utilizan los diagramas de Lundgreen para establecer la distribución por tamaños y la evolución estacional e histórica. Se estudian las fracciones fina y gruesa del aerosol así como su evolución temporal e histórica

Antioxidant and antimicrobial peptide fractions from squid and tuna skin gelatin

27 páginas, 4 figuras, 4 tablas.Gelatin extracted from tuna skins and giant squid tunics were hydrolysed with Alcalase at 50ºC for 3h. Two peptide fractions (1-10K and ≤1K) were obtained from each gelatin hydrolysate by subjecting them to centrifugal ultrafiltration using successively a 10 kDa and a 1 kDa membrane. The peptide fractions were characterized in terms of amino acid composition and Fourier transform infrared (FTIR) spectroscopy. Antioxidant properties were tested according to the Ferric Reducing Antioxidant Power (FRAP) assay and the radical scavenging capacity (ABTS) assay. A disk diffusion test was performed to test antimicrobial action against a panel of Gram-positive and Gramnegative pathogenic and fish spoilage-associated microorganisms. Although antioxidant and antimicrobial properties could be detected in all tested peptide fractions, the lowermost molecular weight fraction from squid hydrolysate presented the highest reducing and radical scavenging capacities, whereas microbial growth inhibition was found to be specifically related to the type of microorganism.This study was supported by the Spanish “Ministerio de Educación y Ciencia” (project AGL2005-02380/ALI and AGL2008-02135/ALI).Peer reviewe

Morphometric variations of banana starches issued from various genomic groups and In vitro starch digestibility

An analysis of shape and size of the granules of starches isolated from the edible portion of eight unripe banana genotypes was performed. The study aimed at investigating the potential of banana starches as ingredients for industrial purposes. It also aimed at investigating their in vitro digestibility in relation to their morphometric characteristics. The granular size distribution and granular morphometric characteristics were determined by diffraction Laser sizing (LDS), light polarized microscopy (LPM), and scanning electronic microscopy (SEM) techniques. Results reveal differences in the starch shape and size without any correlation between the granular profile and the genomic group. Granule shape includes symmetrical and asymmetrical spheres, symmetrical and asymmetrical shell-shapes, tubular-shapes, irregular and ellipsoidal-truncated shapes. Some granules exhibited smooth shapes, whereas others exhibit faceted surfaces. It was also observed some variation in the starch hydrolysis among samples, which was most pronounced in the BB banana starch genotype. The variation of the granular shape and size could be considered as a key for the differentiation of the banana genotypes. Such variation could affect the digestibility of the starches, even gelatinized. Thus, the granular distribution histogram can be used as an indicator of the potential uses of the starch from bananas. Among potential industrial uses, the isolated starch from the BB genotype can be used for paper and cosmetic industry according to its granule small size and uniformity. The other evaluated starches have granular size and shape variations that have to be sorted in relation to their functional properties and how they could affect the process within industrial formulations. (Résumé d'auteur

Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactorsand the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40\,cm long gas cell placed in the beam path of the Aries 40\,m radio telescope receivers operating in the 41-49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH3OH, CH3CH2OH, HCOOH, OCS,CS, SO2 (<1E-03 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O2 and CS2 was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.Comment: Accepted for publication in Astronomy and Astrophysics in September 21, 2017. 16 pages, 18 figure

Skeletal Muscle Mass Indices in Healthy Young Mexican Adults Aged 20–40 Years: Implications for Diagnoses of Sarcopenia in the Elderly Population

Background and Objectives. Skeletal muscle and skeletal muscle indices in young adults from developing countries are sparse. Indices and the corresponding cut-off points can be a reference for diagnoses of sarcopenia. This study assessed skeletal muscle using dual-energy X-ray absorptiometry (DXA) in healthy male and female subjects aged 20–40 years and compared their appendicular skeletal muscle mass (ASM) and total-body skeletal muscle (TBSM) indices using certain cut-off points published in the literature. Methods. A sample of 216 healthy adults men and women from northwest Mexico was included. Body composition was assessed by DXA and several published DXA-derived skeletal muscle indices were compared. Results. Both, ASM and TBSM were higher in men compared to the women group (23.0 ± 3.4 versus 15.9 ± 1.6 kg; P<0.05 and 26.5 ± 4.1 versus 16.9 ± 1.9 kg; P<0.05, resp.). These differences were also valid for both indices. When derived cut-off points were compared with the most reported indices, significant differences were found. Interpretation and Conclusion. Published cut-off points from Caucasians are higher than cut-off point derived in this sample of Mexican subjects. The new DXA-derived cut-off points for ASM proposed herein may improve diagnoses of sarcopenia in the geriatric Mexican population

Type I Interferon Gene Response Is Increased in Early and Established Rheumatoid Arthritis and Correlates with Autoantibody Production

BACKGROUND: Rheumatoid arthritis (RA) is an inflammatory debilitating disease that affects the joints in the early and productive phases of an individual’s life. Several cytokines have been linked to the disease pathogenesis and are known to contribute to the inflammatory state characteristic of RA. The participation of type I interferon (IFN) in the pathogenesis of the disease has been already described as well as the identity of the genes that are regulated by this molecule, which are collectively known as the type I IFN signature. These genes have several functions associated with apoptosis, transcriptional regulation, protein degradation, Th2 cell induction, B cell proliferation, etc. This article evaluated the expression of several genes of the IFN signature in different stages of disease and their correlation with the levels of anticitrullinated protein antibodies (ACPA) anticarbamylated protein (Anti-CarP) antibodies. METHODS: Samples from individuals with early and established RA, high-risk individuals (ACPA+ and ACPA−), and healthy controls were recruited at “Unidad de Artritis y Rheumatismo” (Rheumatism and Arthritis Unit) in Guadalajara Jalisco Mexico. Determinations of ACPA were made with Eurodiagnostica ACPA plus kit. Anti-CarP determinations were made according to previously described protocols. RNA was isolated, and purity and integrity were determined according to RNA integrity number >6. Gene expression analysis was made by RT-qPCR using specific primers for mRNAs of the type I IFN signature. Relative gene expression was calculated according to Livak and Schmitgen. RESULTS: Significant differences in gene expression were identified when comparing the different groups for MXA and MXB (P < 0.05), also when comparing established RA and ACPA− in both IFIT 1 and G15. An increased expression of ISG15 was identified (P < 0.05), and a clear tendency toward increase was identified for HERC5. EPSTRI1, IFI6, and IFI35 were found to be elevated in the chronic/established RA and early RA (P < 0.05). Significant correlations were identified for the IFN signature genes with the levels of ACPA and anti-CarP (P < 0.05). CONCLUSION: Our data confirm previous observations in the role of IFN signature and the pathogenesis of RA. Also, we provide evidence of an association between several genes of the IFN signature (that regulate Th2 cells and B cell proliferation) with the levels of anti-CarP antibodies and ACPA