21 research outputs found
Reacción de Diels-Alder intramolecular organocatalizada usando el anillo de furano como dieno (IMDAF)
Este trabajo fin de grado tiene como objetivo llevar a cabo reacciones enantioselectivas intramoleculares de Diels-Alder empleando el anillo de furano como dieno (conocidas como reacciones IMDAF). Con este fin, se ha llevado a cabo la síntesis de derivados en los que el furano queda unido al filodieno mediante una cadena hidrocarbonada simple (C) o conteniendo un heteroátomo (N, O). En el extremo de dicha cadena siempre se instala un grupo extractor de carga (EWG) para favorecer dicha reacción. Para realizar la cicloadición con estos derivados se han empleando una serie de organocatalizadores que permiten el control de la enantioselectividad del cicloaducto formado.Grado en Químic
Hornos de brea en Tenerife. Identificación y catalogación
La producción de pez o brea tuvo una gran importancia en la economía tinerfeña desde
fines del siglo XV, como recoge la documentación de la época. En este trabajo realizamos
una aproximación a los yacimientos arqueológicos de los hornos de brea, en los siglos XVI y
XVII, mediante su catalogación e identificación en las distintas comarcas históricas del espacio
insular. Estos hornos, aparte de su valor patrimonial, constituyen un indicador de la
ubicación de las masas forestales, de las vías de tránsito o de la dirección de las primeras
producciones de brea en la isla de Tenerife.The production of pitch or tar was of great importance to the Tenerife economy from the
latter part of the XV century, as can be derived from the documentation of the period. In
this work we approach the archaeological strata of the pitch ovens in the XVI and XVII centuries
by cataloguing and identifying them in the various historical territorial divisions of the
island. In addition to their heritage value these ovens are tracers of the locations of the
afforested areas, of the traffic routes, and of the earliest sites where pitch was produced in
the Island of Tenerife
Switching the substrate preference of fungal aryl-alcohol oxidase: towards stereoselective oxidation of secondary benzyl alcohols
Oxidation of primary alcohols by aryl-alcohol oxidase (AAO), a flavoenzyme that provides H2O2 to fungal peroxidases for lignin degradation in nature, is achieved by concerted hydroxyl proton transfer and stereoselective hydride abstraction from the pro-R benzylic position. In racemic secondary alcohols, the R-hydrogen abstraction would result in the selective oxidation of the S-enantiomer to the corresponding ketone. This stereoselectivity of AAO may be exploited for enzymatic deracemization of chiral mixtures and isolation of R-enantiomers of industrial interest by switching the enzyme activity from primary to secondary alcohols. A combination of computational simulations and mutagenesis has been used to produce AAO variants with increased activity on secondary alcohols, using the already available F501A variant of Pleurotus eryngii AAO as a starting point. Adaptive-PELE simulations for the diffusion of (S)-1-(p-methoxyphenyl)-ethanol in this variant allowed Ile500 to be identified as one of the key residues with a higher number of contacts with the substrate during its transition from the solvent to the active site. Substitution of Ile500 produced more efficient variants for the oxidation of several secondary alcohols, and the I500M/F501W double variant was able to fully oxidize (after 75 min) with high selectivity (ee >99%) the S-enantiomer of the model secondary aryl-alcohol (±)-1-(p-methoxyphenyl)-ethanol, while the R-enantiomer remained unreacted.This work was supported by the INDOX (KBBE-2013-7-613549) EU project and by the BIO2017-86559-R (GenoBioref), CTQ2016-79138-R and BIO2016-79106-R projects of the Spanish Ministry of Economy, Industry and Competitiveness, cofinanced by FEDER funds. Pedro Merino (University of Zaragoza, Spain) is acknowledged for his suggestions on chiral HPLC analyses.Peer ReviewedAward-winningPostprint (published version
Life-long spontaneous exercise does not prolong lifespan but improves health span in mice
BackgroundLife expectancy at birth in the first world has increased from 35 years at the beginning of the 20th century to more than 80 years now. The increase in life expectancy has resulted in an increase in age-related diseases and larger numbers of frail and dependent people. The aim of our study was to determine whether life-long spontaneous aerobic exercise affects lifespan and healthspan in mice.ResultsMale C57Bl/6J mice, individually caged, were randomly assigned to one of two groups: sedentary (n = 72) or spontaneous wheel-runners (n = 72). We evaluated longevity and several health parameters including grip strength, motor coordination, exercise capacity (VO2max) and skeletal muscle mitochondrial biogenesis. We also measured the cortical levels of the brain-derived neurotrophic factor (BDNF), a neurotrophin associated with brain plasticity. In addition, we measured systemic oxidative stress (malondialdehyde and protein carbonyl plasma levels) and the expression and activity of two genes involved in antioxidant defense in the liver (that is, glutathione peroxidase (GPx) and manganese superoxide dismutase (Mn-SOD)). Genes that encode antioxidant enzymes are considered longevity genes because their over-expression may modulate lifespan. Aging was associated with an increase in oxidative stress biomarkers and in the activity of the antioxidant enzymes, GPx and Mn-SOD, in the liver in mice. Life-long spontaneous exercise did not prolong longevity but prevented several signs of frailty (that is, decrease in strength, endurance and motor coordination). This improvement was accompanied by a significant increase in the mitochondrial biogenesis in skeletal muscle and in the cortical BDNF levels.ConclusionLife-long spontaneous exercise does not prolong lifespan but improves healthspan in mice. Exercise is an intervention that delays age-associated frailty, enhances function and can be translated into the clinic
Seroprevalence of Toxoplasma gondii and Neospora caninum in goats from north-western Spain
Introduction and objective:
Toxoplasma gondii and Neospora caninum are protozoans involved in reproductive failure especially in ruminant livestock. The objective was to estimate the seroprevalence of both parasites in goats from north-western Spain and to study the influence of some factors on seropositivity.
Material and Methods:
Blood samples from 638 goats were collected in 50 farms. Presence of T. gondii and N. caninum antibodies were detected by direct agglutination and competitive ELISA techniques, respectively. The risk factor analysis was performed using a mixed-effects logistic regression.
Results:
Individual (48%) and herd-level (74%) T. gondii seroprevalence values were high; the within-herd prevalence was 53%. In contrast, 6% of animals tested positive to N. caninum and 38% of the herds had at least one positive animal, with a true within-herd prevalence of 10%. Mixed infections were limited; 91% of N. caninum seropositive goats were also positive to T. gondii The risk factor analysis showed that T. gondii seroprevalence is influenced by the presence of sheep in the farm (OR=4.9) and the seropositivity to N. caninum (OR=16.5); goats from the Central-coastal area, more humid and warm, had a 15.7-fold probability of being seropositive to T. gondii than those from the Mountainous area. Cross-breed goats (OR=4.5) and the seropositivity to [i]T. gondii [/i](OR= 9.5) were factors associated with N. caninum seropositivity.
Conclusions:
The high T. gondii seroprevalence in goats constitute a noticeable zoonotic risk. The consideration of the risk factors identified in designing T. gondii and N. caninum control programs in goat herds should allow the implementation of more efficient measures, avoiding the appearance of outbreaks of reproductive disorders by both protozoans in goatsThe authors express their thank to OVICA (Galician
Association of Ovine and Caprine Breeders), BOAGA
(Galician Autochthonous Breed Federation) and the
veterinarians of the ADSG ACIVO for their collaboration
in this study. This work was supported by a Programme for
consolidating and structuring competitive research groups
(GRC2015/003, Xunta de Galicia) and by the Research
Project ‘RUMIGAL: Rede de estudomultidisciplinar dos
ruminantesen Galicia’ (R2014/005, REDES, Xunta de
Galicia)S
II Jornadas Internacionales Colegio Profesional de Logopedas de Galicia
Este libro recoge las ponencias presentadas en las II Jornadas Internacionales organizadas por el Colegio Profesional de Logopedas de Galicia, que se celebraron durante los días 15 y 16 de noviembre en la Facultade de Ciencias da Educación da Universidade da Coruñ
Jardins per a la salut
Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia. Assignatura: Botànica farmacèutica. Curs: 2014-2015. Coordinadors: Joan Simon, Cèsar Blanché i Maria Bosch.Els materials que aquí es presenten són el recull de les fitxes botàniques de 128 espècies presents en el Jardí Ferran Soldevila de l’Edifici Històric de la UB. Els treballs han estat realitzats manera individual per part dels estudiants dels grups M-3 i T-1 de l’assignatura Botànica Farmacèutica durant els mesos de febrer a maig del curs 2014-15 com a resultat final del Projecte d’Innovació Docent «Jardins per a la salut: aprenentatge servei a Botànica farmacèutica» (codi 2014PID-UB/054). Tots els treballs s’han dut a terme a través de la plataforma de GoogleDocs i han estat tutoritzats pels professors de l’assignatura. L’objectiu principal de l’activitat ha estat fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica. També s’ha pretès motivar els estudiants a través del retorn de part del seu esforç a la societat a través d’una experiència d’Aprenentatge-Servei, deixant disponible finalment el treball dels estudiants per a poder ser consultable a través d’una Web pública amb la possibilitat de poder-ho fer in-situ en el propi jardí mitjançant codis QR amb un smartphone
Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported
by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on
18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based
researchers who signed it in the short time span from 20 September to 6 October 2016
Biliopleural fistula after radiofrecuency ablation of hepatocellular carcinoma Fístula biliopleural tras la ablación con radiofrecuencia de un carcinoma hepatocelular
Enhancing thermostability by modifying flexible surface loops in an evolved high-redox potential laccase
[EN] High-redox potential laccases (HRPLs) from white-rot fungi are versatile biocatalysts whose practical use is highly dependent on their thermostability. In this work, an evolved HRPL variant was subjected to structure-guided evolution to improve its thermostability. We first selected several surface flexible loops in the laccase structure by inspecting them through molecular dynamics and an analysis of B-factors. The resulting segments were grouped into three MORPHING (Mutagenic Organized Recombination Process by Homologous In vivo Grouping) blocks, which were constructed in Saccharomyces cerevisiae and explored at high temperatures. This evolution process gave rise to a double mutant that showed a half-life at 70°C enhanced by 31 min with an optimum temperature for activity of 75°C and similar kinetic parameters. The Ser264Lys and Ser356Asn mutations modified the contacts established between these residues and those that surround them, altering the surface loops and thereby the enzyme properties.FP7 Food, Agriculture and Fisheries, Biotechnology, Grant/Award Numbers: FP7‐KBBE‐2013‐7‐613549‐INDOX, COST‐ActionCM1303; Ministerio de Ciencia e Innovación, Grant/Award Numbers: BIO2016‐79106‐R‐Lignolution, CTQ2016‐79138‐