686 research outputs found

    3D architecture of DNA Pol α reveals the functional core of multi-subunit replicative polymerases

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    Eukaryotic DNA replication requires the coordinated activity of the multi-subunit DNA polymerases: Pol α, Pol δ and Pol ɛ. The conserved catalytic and regulatory B subunits associate in a constitutive heterodimer that represents the functional core of all three replicative polymerases. Here, we combine X-ray crystallography and electron microscopy (EM) to describe subunit interaction and 3D architecture of heterodimeric yeast Pol α. The crystal structure of the C-terminal domain (CTD) of the catalytic subunit bound to the B subunit illustrates a conserved mechanism of accessory factor recruitment by replicative polymerases. The EM reconstructions of Pol α reveal a bilobal shape with separate catalytic and regulatory modules. Docking of the B–CTD complex in the EM reconstruction shows that the B subunit is tethered to the polymerase domain through a structured but flexible linker. Our combined findings provide a structural template for the common functional architecture of the three major replicative DNA polymerases

    Developing Transdermal Applications of Ketorolac Tromethamine Entrapped in Stimuli Sensitive Block Copolymer Hydrogels

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    Purpose: In order to obtain dermal vehicles of ketorolac tromethamine (KT) for the local treatment of inflammation and restrict undesirable side effects of systemic levels hydrogels (HGs) of poloxamer and carbomer were developed. Methods: KT poloxamer based HG (KT-P407-HG) and KT carbomer based HG (KT-C940-HG) were elaborated and characterized in terms of swelling, degradation, porosity, rheology, stability, in vitro release, ex vivo permeation and distribution skin layers. Finally, in vivo anti-inflammatory efficacy and skin tolerance were also assessed. Results: HGs were transparent and kept stable after 3 months exhibiting biocompatible near neutral pH values. Rheological patterns fitted to Herschel-Bulkley for KT-C940-HG and Newton for KT-P407-HG due to its low viscosity at 25°C. Rapid release profiles were observed through first order kinetics. Following the surface the highest concentration of KT from C940-HG was found in the epidermis and the stratum corneum for P407-HG. Relevant anti-inflammatory efficacy of KT-P407-HG revealed enough ability to provide sufficient bioavailability KT to reach easily the site of action. The application of developed formulations in volunteers did not induce any visual skin irritation. Conclusions: KT-P407-HG was proposed as suitable formulation for anti-inflammatory local treatment without theoretical systemic side effect

    Correcting non cephalic presentation with moxibustion: study protocol for a multi-centre randomised controlled trial in general practice

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    <p>Abstract</p> <p>Background</p> <p>Non cephalic presentation in childbirth involves various risks to both the mother and the foetus. The incidence in Spain is 3.8% of all full-term pregnancies. The most common technique used to end the gestation in cases of non cephalic presentation is that of caesarian section, and although it provokes a lower rate of morbi-mortality than does vaginal delivery in such situations, there remains the possibility of traumatic injury to the foetal head and neck, while maternal morbidity is also increased. The application of heat (moxibustion) to an acupuncture point, in order to correct non cephalic presentation, has been practised in China since ancient times, but as yet there is insufficient evidence of its real effectiveness.</p> <p>Methods/Design</p> <p>The experimental design consists of a multi-centre randomised controlled trial with three parallel arms, used to compare real moxibustion, sham moxibustion and the natural course of events, among pregnant women with a non cephalic presentation and a gestational duration of 33–35 weeks (estimated by echography). The participants in the trial will be blinded to both interventions. The results obtained will be analyzed by professionals, blinded with respect to the allocation to the different types of intervention. In addition, we intend to carry out a economic analysis.</p> <p>Discussion</p> <p>This trial will contribute to the development of evidence concerning moxibustion in the correction of non cephalic presentations. The primary outcome variable is the proportion of cephalic presentations at term. As secondary outcomes, we will evaluate the proportion of cephalic presentations at week 38 of gestation, determined by echography, together with the safety of the technique, the specificity of moxibustion and the control of the blinding process.</p> <p>This study has been funded by the Health Ministry of the Andalusian Regional Government.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN10634508.</p

    Glutamate receptor-like channels are essential for chemotaxis and reproduction in mosses

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    The deposited article version is a "Accelerated Article Preview" provided by Nature Publishing Group, and it contains attached the supplementary materials within the pdf.». This publication hasn't any creative commons license associated.Glutamate receptors are well characterized channels that mediate cell-to-cell communication during neurotransmission in animals. Nevertheless, information regarding their functional role in organisms without nervous systems is still limited. In plants, Glutamate Receptor-like (GLR) genes have been implicated in defence against pathogens, reproduction, control of stomata aperture and light signal transduction(1-5). However, the numerous GLR genes present in angiosperm genomes (20 to 70)(6) has prevented the observation of strong phenotypes in loss-of-function mutants. Here, we show that in the moss Physcomitrella patens, a basal land plant, mutation of GLR genes cause sperm failure in targeting the female reproductive organs. In addition, we show that GLR genes encode non-selective Ca(2+) permeable channels that can regulate cytoplasmic Ca(2+) and are needed to induce the expression of a BELL1-like transcription factor essential for zygote development. Our work reveals novel functions for GLRs in sperm chemotaxis and transcriptional regulation. Sperm chemotaxis is essential for fertilization in both animals and early land plants like bryophytes and pteridophytes. Therefore, our results are suggestive that ionotropic glutamate receptors may have been conserved throughout plant evolution to mediate cell-to-cell communication during sexual reproduction.Phillips University; Oxford University; University of Marburg; University of Muenster; MarieCurie ITN-Plant Origins grant: (FP7-PEOPLE-ITN-2008); FCT grants: (BEX-BCM/0376/2012; PTDC/BIA-PLA/4018/2012); NSF-US grant: (MCB 1616437/2016).info:eu-repo/semantics/acceptedVersio

    A colorectal cancer susceptibility new variant at 4q26 in the Spanish population identified by genome-wide association analysis

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    This work was partially supported by the CENIT program from the Centro Tecnológico Industrial (CEN-20091016), grants from the Spanish Institute of Health Carlos III (ADE10/00026, PI09/02444, PI12/00511, Acción Transversal de Cáncer) grants from the Fondo de Investigacion Sanitaria/FEDER (08/1276, 08/0024, PS09/02368, 11/00219, 11/00681), and by COST office through COST action BM1206. SCB is supported by contracts from the Fondo de Investigación Sanitaria (CP 03-0070). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Centro Tecnológico IndustrialInstituto de Salud Carlos IIIFondo de Investigación Sanitaria / FEDE

    Ectomycorrhizal fungal diversity and community structure associated with cork oak in different landscapes

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    Cork oak (Quercus suber L.) forests play an important ecological and economic role. Ectomycorrhizal fungi (ECMF) are key components for the sustainability and functioning of these ecosystems. The community structure and composition of ECMF associated with Q. suber in different landscapes of distinct Mediterranean bioclimate regions have not previously been compared. In this work, soil samples from cork oak forests residing in different bioclimates (arid, semi-arid, sub-humid, and humid) were collected and surveyed for ectomycorrhizal (ECM) root tips. A global analysis performed on 3565 ECM root tips revealed that the ECMF community is highly enriched in Russula, Tomentella, and Cenoccocum, which correspond to the ECMF genera that mainly contribute to community differences. The ECMF communities from the rainiest and the driest cork oak forests were distinct, with soils from the rainiest climates being more heterogeneous than those from the driest climates. The analyses of several abiotic factors on the ECMF communities revealed that bioclimate, precipitation, soil texture, and forest management strongly influenced ECMF structure. Shifts in ECMF with different hyphal exploration types were also detected among forests, with precipitation, forest system, and soil texture being the main drivers controlling their composition. Understanding the effects of environmental factors on the structuring of ECM communities could be the first step for promoting the sustainability of this threatened ecosystem.This work was supported by Fundacao Ciencia e Tecnologia (FCT/MCTES/PIDDAC, Portugal), under the project (PEst-OE/BIA/UI4046/2014; UID/MULTI/04046/2013) and PhD grant to F.R. (SFRH/BD/86519/2012)

    Molecular Refinement of Clinical Staging in Hepatocellular Carcinoma Patients Evaluated for Potentially Curative Therapies

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    Abstract: Aim: VEGF and AFP mRNA determinations in the blood are promising prognostic factors for patients with HCC. This study explores their potential prognostic synergy in a cohort of HCC patients evaluated for potentially curative therapies. Methods: One hundred twenty-four patients with a diagnosis of HCC were prospectively enrolled in the study. Inclusion criteria were: (a) histological diagnosis of HCC and assessment of tumour grade and (b) determination of AFP mRNA status and VEGF levels in the blood before therapy. Results: At baseline evaluation, 40% of the study group had AFP mRNA in the blood (AFP mRNA positive), and 35% had VEGF > 23 pg ml(-1) (VEGF positive). Surgery was performed in 58 patients (47%), 54 (43%) had tumour ablation, and 12 had chemoembolisation (10%). Median follow-up and survival of the study group were 19 and 26 months (range, 1 to 60), respectively. The association of AFP mRNA and VEGF proved to be prognostically more accurate than their single use in discriminating the risk of death (ROC curve analysis) and survival probability (Cox analysis). In particular, we identified 3 main molecular stages (p < 0,0001): both negative (3-year survival = 63%), one positive (3-year survival = 40%), both positive (3-year survival = 16%). Multivariate analysis identified BCLC staging, surgery, and molecular staging as the most significant survival variables. Conclusions: The preoperative determination of AFP mRNA status and VEGF may potentially refine the prognostic evaluation of HCC patients and improve the selection process for potentially curative therapies
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