34 research outputs found

    Performance of a series of novel N-substituted acrylamides in capillary electrophoresis of DNA fragments

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    DNA separations by capillaryelectrophoresis in viscous solutions of novel polymers, made with \u3a9-hydroxyl, N-substitutedacrylamides (notably N-acryloyl amino propanol, AAP and N-acryloyl amino butanol, AAB) are evaluated. Whereas in standard poly(acrylamide), at 6% concentration, the theoretical plate number (N) does not exceed 500 000, in 6% poly(AAP) N reaches 922 000 and in 6% poly(AAB) N values as high as 1 200 000 are obtained. Also, copolymers of AAP and AAB give N values in excess of 1 million plates. The two novel monomers (AAP and AAB) remain extremely stable during alkaline hydrolysis and display very good hydrophilicity, while being devoid of the noxious habit of auto-polymerization and auto-reticulation exhibited by the previous monomer of this series (N-acryloyl amino ethoxy ethanol). The reasons for such a good performance of the \u3a9-substituted acrylamide derivatives could be that their polymers may form hydrogen bonds via their distal -OH group during DNA separation

    Study of failures in a rabbit line selected for growth rate

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    [EN] Selection for growth rate is negatively related with reproductive fitness. The aim of this work was to analyse the causes of fertility failure in rabbit does selected for growth rate and characterised for reproductive deficiencies (line R). In the experiment, 82 does were divided into 2 groups: naturally mated (NM) and artificially inseminated (AI), to relate luteinizing hormone (LH) concentration with ovulation induction and pregnancy rate by laparoscopic determination. Additionally, in 38 of these females ovulation rate and metabolites determination (leptin, NEFA, BOHB and glucose) were analysed and perirenal fat thickness measurement and live body weight (LBW) determined. The results showed that all ovulated does (both NM and AI) presented higher concentrations of LH than non-ovulated females. In addition, non-ovulated females showed high levels of leptin and BOHB, as well as LBW. Females from line R have an inherit reduced fertility due to ovulation failure as a consequence of a reduction in LH release, which could be explained by a heavier body weight and higher leptin concentrations.This work was supported by the Spanish Research Project AGL2011-30170-C02-01 (CICYT). Carmen Naturil-Alfonso was supported by a research grant from the Education Ministry of the Valencian Regional Government (programme VALi+d. ACIF/2013/296). English text version was revised by N. Macowan English Language Service.Naturil Alfonso, C.; Lavara García, R.; Millán, P.; Rebollar, P.; Vicente Antón, JS.; Marco Jiménez, F. (2016). Study of failures in a rabbit line selected for growth rate. World Rabbit Science. 24(1):47-53. https://doi.org/10.4995/wrs.2016.4016SWORD475324

    First-line single-agent regorafenib in frail patients with metastatic colorectal cancer: a pilot phase II study of the Spanish Cooperative Group for the Treatment of Digestive Tumours (TTD)

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    BackgroundTreatment of frail patients with advanced colorectal cancer (CRC) is controversial. This pilot phase II trial aimed to assess the efficacy and safety of regorafenib when administered in first-line to frail patients with advanced CRC.MethodsFrail patients without prior advanced colorectal cancer treatment were included in the study. Definition of frailty was defined per protocol based on dependency criteria, presence of chronic comorbid pathologies and/or geriatric features. Main objective: to assess progression-free survival (PFS) rate at 6months. Treatment consisted of 28-daycycles of orally administered regorafenib 160mg/day (3 weeks followed by 1 week rest).ResultsForty-seven patients were included in the study. Median age was 81years (range 63-89). Frailty criteria: dependency was observed in 26 patients (55%), comorbidities in 27 (57%) and geriatric features in 18 (38%). PFS rate at 6months was 45% (95% confidence interval [CI] 30-60]. Median PFS was 5.6months (95%CI 2.7-8.4). Median overall survival (OS) was 16months (95%CI 7.8-24). Complete response, partial response and stable disease were observed in one, two and 21 patients respectively (objective response rate 6.4%; disease control rate 51%). Thirty-nine patients (83%) experienced grade 3-4 adverse events (AEs). The most common grade 3-4 AEs were hypertension (15 patients; 32%), asthenia (14; 30%), hypophosphatemia (6; 13%); diarrhea (4; 8%), hand-foot-skin reaction (4; 8%). There were two toxic deaths (4.2%) (grade 5 rectal bleeding and death not further specified). Dose reduction was required in 26 patients (55%) and dose-delays in 13 patients (28%).ConclusionsThe study did not meet the pre-specified boundary of 55% PFS rate at 6months. Toxicity observed (83% patients experienced grade 3 and 4 AEs) preclude its current use in clinical practice on this setting. Disease control rate and overall survival results are interesting and might warrant further investigation to identify those who benefit from this approach.Trial registrationThis trial was prospectively registered at EudraCT (2013-000236-94). Date of trial registration: April 9th, 2013

    Anisotropic optical response of the diamond (111)-2x1 surface

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    The optical properties of the 2×\times1 reconstruction of the diamond (111) surface are investigated. The electronic structure and optical properties of the surface are studied using a microscopic tight-binding approach. We calculate the dielectric response describing the surface region and investigate the origin of the electronic transitions involving surface and bulk states. A large anisotropy in the surface dielectric response appears as a consequence of the asymmetric reconstruction on the surface plane, which gives rise to the zigzag Pandey chains. The results are presented in terms of the reflectance anisotropy and electron energy loss spectra. While our results are in good agreement with available experimental data, additional experiments are proposed in order to unambiguously determine the surface electronic structure of this interesting surface.Comment: REVTEX manuscript with 6 postscript figures, all included in uu file. Also available at http://www.phy.ohiou.edu/~ulloa/ulloa.html Submitted to Phys. Rev.

    Novel functionalised imidazo-benzocrown ethers bearing a thiophene spacer as fluorimetric chemosensors for metal ion detection

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    Novel phenylalanine derivatives bearing benzimidazole and crown ethers as coordinating/reporting units and thiophene as a spacer unit were synthesized for the first time, and their evaluation as fluorimetric chemosensors was carried out in acetonitrile and acetonitrile/water solutions. 15-Crown-5 benzimidazolyl phenylalanine methyl ester, 15-crown-5 thienylbenzimidazolyl phenylalanine methyl ester and 18-crown-6 thienylbenzimidazolyl phenylalanine methyl ester were tested for alkaline, alkaline-earth and transition metal ions (such as Na+, Ca2+, Cd2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, Hg2+, Ni2+, Pd2+ and Zn2+). The different crown ether binding moieties as well as the electronic nature and the length of the π-bridge linked to the benzimidazole heterocycle allowed the fine tuning of the sensory properties as seen by spectrofluorimetric titrations. Therefore, 15-crown-5 benzimidazolyl phenylalanine methyl ester is a fluorimetric chemosensor, being selective and sensitive for Cu2+ and Pd2+ in aqueous solutions (ACN/H2O; 80:20). On the other hand, the metal cation sensing properties displayed by 15-crown-5 thienylbenzimidazolyl phenylalanine methyl ester bearing an arylthienyl spacer showed that this is a promising candidate as fluorimetric chemosensor for Fe3+, Pb2+ and Pd2+ in acetonitrile solution.Thanks are due to Fundação para a Ciência e Tecnologia (Portugal) for financial support to the Portuguese NMR network (PTNMR, Bruker Avance III 400-Univ. Minho), FCT and FEDER (European Fund for Regional Development)-COMPETEQREN-EU for financial support to the research centre CQ/UM [PEst-C/QUI/UI0686/2013 (FCOMP-01-0124-FEDER-037302], a PhD grant to C.I.C. Esteves (SFRH/BD/68360/2010) and a post-doctoral grant to R.M.F. Batista (SFRH/BPD/79333/2011).info:eu-repo/semantics/publishedVersio

    Lentivírus de pequenos ruminantes (CAEV e Maedi-Visna): revisão e perspectivas

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    Whole-genome sequencing reveals host factors underlying critical COVID-19

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    Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
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