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991.
992.
Rafael Bielza Galindo Jesús Llorente Gutiérrez José Luis Pérez González Asunción Mora Casado David Blanco Díaz Javier Escalera Alonso Adoración Morales Fernández Cristina Molano Ortiz Beredys Esmirla García López Nazaret del Amo del Arco Juan Pablo Barro Ordovas Estefanía Arias Muñana Marta Neira Álvarez David Sanz Rosa Jorge Fco. Gómez Cerezo 《Revista espa?ola de geriatría y gerontología》2018,53(1):38-44
Introduction
There are no previous studies evaluating the effect of intravenous iron therapy on functional and cognitive status of patients with hip fracture (HF).Material and methods
A single-centre randomised, placebo-controlled, double-blind and parallel treatment, clinical trial has been designed to assess the efficacy of intravenous iron therapy during the peri-operative period in elderly patients suffering from a HF. Blinding will be ensured by the packaging of the drug infusion system. On days 1, 3, and 5 from admission, the intervention group will receive 200 mg Venofer® (iron sucrose) diluted in 100 ml saline, and the control group 100 ml saline, also on days 1, 3 and 5. Patients will received conventional treatment in ortho-geriatric unit of the Hospital Infanta Sofia. Functional variables (activities of daily living and walking), cognitive (cognitive status and delirium), surgical, demographic and clinical characteristics will be collected during admission in order to assess the impact of treatment. A safety analysis of the treatment will also performed. Patients will be followed-up at 3, 6, and 12 months.Results
The study will attempt to provide evidence on the impact of the intravenous iron administration on functional recovery. It will be determined whether iron therapy negatively affects the incidence of post-operative delirium. Finally, report will be presented on the safety data of intravenous iron in elderly HF patients, as well as the impact on allogenic blood transfusion savings.Conclusions
The inclusion of elderly HF patients admitted to an ortho-geriatric unit, in a clinical trial, will help to improve the knowledge of the treatment impact on a usual scenario, and provide useful data for use in other units. 相似文献993.
994.
995.
Toward a general mixed quantum/classical method for the calculation of the vibronic ECD of a flexible dye molecule with different stable conformers: Revisiting the case of 2,2,2‐trifluoro‐anthrylethanol 下载免费PDF全文
Javier Cerezo Daniel Aranda Francisco J. Avila Ferrer Giacomo Prampolini Giuseppe Mazzeo Giovanna Longhi Sergio Abbate Fabrizio Santoro 《Chirality》2018,30(6):730-743
We extend a recently proposed mixed quantum/classical method for computing the vibronic electronic circular dichroism (ECD) spectrum of molecules with different conformers, to cases where more than one hindered rotation is present. The method generalizes the standard procedure, based on the simple Boltzmann average of the vibronic spectra of the stable conformers, and includes the contribution of structures that sample all the accessible conformational space. It is applied to the simulation of the ECD spectrum of (S)‐2,2,2‐trifluoroanthrylethanol, a molecule with easily interconvertible conformers, whose spectrum exhibits a pattern of alternating positive and negative vibronic peaks. Results are in very good agreement with experiment and show that spectra averaged over all the sampled conformational space can deviate significantly from the simple average of the contributions of the stable conformers. The present mixed quantum/classical method is able to capture the effect of the nonlinear dependence of the rotatory strength on the molecular structure and of the anharmonic couplings among the modes responsible for molecular flexibility. Despite its computational cost, the procedure is still affordable and promises to be useful in all cases where the ECD shape arises from a subtle balance between vibronic effects and conformational variety. 相似文献
996.
997.
Cristina Pérez-Arnaiz Natalia Busto Javier Santolaya José M. Leal Giampaolo Barone Begoña García 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(3):522-531
Background
Stabilization of G-quadruplex helices by small ligands has attracted growing attention because they inhibit the activity of the enzyme telomerase, which is overexpressed in > 80% cancer cells. TMPyP4, one of the most studied G-quadruplex ligands, is used as a model to show that the ligands can exhibit different binding features with different conformations of a human telomeric specific sequence.Methods
UV–Vis, FRET melting Assay, Isothermal Titration Calorimetry, Time-resolved Fluorescence lifetime, T-Jump and Molecular Dynamics.Results
TMPyP4 yields two different complexes with two Tel22 telomeric conformations in the presence of Na+ or K+. T-Jump kinetic experiments show that the rates of formation and dissociation of these complexes in the ms time scale differ by one order of magnitude. MD simulations reveal that, in K+ buffer, “hybrid 1” conformation yields kinetic constants on interaction with TMPyP4 one order lower than “hybrid 2”. The binding involves π–π stacking with external loop bases.Conclusions
For the first time we show that for a particular buffer TMPyP4 interacts in a kinetically different way with the two Tel22 conformations even if the complexes formed are thermodynamically indistinguishable.General significance
G-quadruplexes, endowed with technological applications and potential impact on regulation mechanisms, define a new research field. The possibility of building different conformations from same sequence is a complex issue that confers G-quadruplexes very interesting features. The obtaining of reliable kinetic data constitutes an efficient tool to determine reaction mechanisms between conformations and small molecules. 相似文献998.
999.
Corrado Marcenò Riccardo Guarino Javier Loidi Mercedes Herrera Maike Isermann Ilona Knollová Lubomír Tichý Rossen T. Tzonev Alicia Teresa Rosario Acosta Úna FitzPatrick Dmytro Iakushenko John A. M. Janssen Borja Jiménez‐Alfaro Zygmunt Kącki Iva Keizer‐Sedláková Vitaliy Kolomiychuk John S. Rodwell Joop H. J. Schaminée Urban Šilc Milan Chytrý 《应用植被学》2018,21(3):533-559
1000.
Confocal microscopy reveals in planta dynamic interactions between pathogenic,avirulent and non‐pathogenic Pseudomonas syringae strains 下载免费PDF全文
José S. Rufián Alberto P. Macho David S. Corry John W. Mansfield Javier Ruiz‐Albert Dawn L. Arnold Carmen R. Beuzón 《Molecular Plant Pathology》2018,19(3):537-551
Recent advances in genomics and single‐cell analysis have demonstrated the extraordinary complexity reached by microbial populations within their hosts. Communities range from complex multispecies groups to homogeneous populations differentiating into lineages through genetic or non‐genetic mechanisms. Diversity within bacterial populations is recognized as a key driver of the evolution of animal pathogens. In plants, however, little is known about how interactions between different pathogenic and non‐pathogenic variants within the host impact on defence responses, or how the presence within a mixture may affect the development or the fate of each variant. Using confocal fluorescence microscopy, we analysed the colonization of the plant apoplast by individual virulence variants of Pseudomonas syringae within mixed populations. We found that non‐pathogenic variants can proliferate and even spread beyond the inoculated area to neighbouring tissues when in close proximity to pathogenic bacteria. The high bacterial concentrations reached at natural entry points promote such interactions during the infection process. We also found that a diversity of interactions take place at a cellular level between virulent and avirulent variants, ranging from dominant negative effects on proliferation of virulent bacteria to in trans suppression of defences triggered by avirulent bacteria. Our results illustrate the spatial dynamics and complexity of the interactions found within mixed infections, and their potential impact on pathogen evolution. 相似文献