Tetranuclear coordination assemblies based on half-sandwich ruthenium(II) complexes. Non covalent binding to DNA and cytotoxicity.

The reaction of [(cymene)RuCl2]2 with K2Hoxonate (H3oxonic = 4,6-dihydroxy-2-carboxy-1,3,5-triazine acid) in methanol leads to the formation of the dinuclear half-sandwich ruthenium(II) complex [(cymene)2Ru2(\u3bc-Hoxonato)Cl2] (1a). Removal of the chloride ligands of 1a by treatment with AgCF3SO3 yields [(cymene)2Ru2(\u3bc-Hoxonato)(CF3SO3)2] (1b), which, upon posterior reaction with N,N'-linkers (L = 4,4'-bipyridine (4,4'-bpy), 4,7-phenantroline (4,7-phen)), gives rise to the formation of the tetranuclear open boxes [(cymene)4Ru4(\u3bc-Hoxonato)2(\u3bc-N,N'-L)2](CF3SO3)4 (2a, L = 4,4'-bpy; 2b, L = 4,7-phen). These systems have been characterized by 1HNMR, UV-vis, and ESI-MS. The single-crystal structures of the dinuclear precursor 1a and of the clathrate 2b 824,7-phen have been determined. The interaction of these systems with cysteine, mononucleotides, and calf-thymus DNA has been studied by means of 1HNMR, UV-vis, circular dicroism, competitive binding assays, and atomic force microscopy imaging. The results show that the robust tetracationic ruthenium(II) cyclic systems 2a and 2b do not give ligand exchange reactions toward biorelevant ligands. Nevertheless, these systems are able to noncovalently bind to DNA, probably at the surface of the major groove, inducing significant conformational changes in this biomolecule. It is also interesting to note that compounds 2a and 2b, in spite of only giving supramolecular interactions with biomolecules, exhibit antitumor activity, particularly toward the human ovarian cancer cell line A2780cisR, showing acquired resistance to cisplatin, with respective 4.6 and 8.3 microM IC50 values

Percepciones de los futuros docentes respecto al potencial de la ludificación y la inclusión de los videojuegos en los procesos de enseñanza-aprendizaje

El trabajo pretende analizar las percepciones de los estudiantes de los grados de Educación Infantil, Primaria y Pedagogía de distintas universidades españolas y latinoamericanas respecto al potencial y uso de la ludificación en el aula para la mejora de los rendimientos y valorar la inclusión del videojuego en los entornos personales de aprendizaje de dicho alumnado analizando las posibilidades pedagógicas del mismo, el potencial para la creación de comunidades de aprendizaje y las opciones para procesos de transformación social. En este sentido, se perseguía conocer el potencial educativo de la ludificación y la adecuación del uso de videojuegos en las etapas de Educación Infantil y Primaria gracias a las percepciones de los futuros docentes en formación. Para ello se desarrolló un estudio descriptivo mediante una encuesta transversal con una muestra de 197 participantes. Los resultados han sido muy positivos respecto a estas herramientas: los fututos docentes están totalmente convencidos de que la ludificación será una herramienta más que estimulante para el alumnado, considerando que los estudiantes trabajarían en el aula con mayor entusiasmo; además, el uso de videojuegos supondrá una influencia en los discentes que fomente la adquisición de las competencias clave establecidas por la legislación educativa.El treball pretén analitzar les percepcions dels estudiants dels graus d'Educació Infantil, Primària i Pedagogia de diferents universitats espanyoles i llatinoamericanes pel que fa al potencial i ús de la ludificació i els videojocs a l'aula per a la millora dels rendiments, i valorar la inclusió del videojoc en els entorns personals d'aprenentatge de l'alumnat analitzant les possibilitats pedagògiques d'aquest, el potencial per a la creació de comunitats d'aprenentatge i les opcions per a processos de transformació social. En aquest sentit, es persegueix conèixer el potencial educatiu de la ludificació i l'adequació de l'ús de videojocs a les etapes d'Educació Infantil i Primària a partir de les percepcions dels futurs docents. Per fer-ho, es va dur a terme un estudi descriptiu mitjançant la tècnica de l'enquesta transversal amb una mostra de 197 participants. Els resultats i les conclusions han estat molt positius pel que fa a aquestes eines; així, els futures docents estan totalment convençuts que la ludificació serà una eina més que estimulant per a l'alumnat, considerant que els alumnes treballarien a l'aula amb més entusiasme; a més, l'ús de videojocs suposarà una influència en els estudiants que fomentarà l'adquisició de les competències clau establertes per la legislació educativa.This paper analyzes the perceptions of students enrolled in bachelor's degree programs in early childhood education, primary education and pedagogy at various Spanish and Latin American universities regarding the potential use of gamification in classrooms to improve academic performance and evaluate the inclusion of video games in the personal learning environments of these students. The educational possibilities, the potential for the creation of learning communities and the main options for social transformation processes of these teaching tools are analyzed. The article seeks to determine the educational potential of gamification and the appropriate use of video games in pre-school and primary education through the perceptions of future teachers. To this end, a descriptive study using a crosssectional survey with a sample of 197 participants is carried out. The results are very positive regarding these tools: future teachers are fully convinced that gamification is a very stimulating tool for students as it motivates them to work in the classroom. Moreover, the use of video games promotes the acquisition of key competencies established under the educational legislation

Thermally induced interconversions of metal-pyrimidine-4,6-dicarboxylate polymers: A structural, spectroscopic, and magnetic study

Continuing our work on the structural and magnetic aspects of the one-dimensional (1-D) coordination polymers of the [M(pmdc)(H2O)2]\ub7H2O kind (M Fe, Co, Ni, Cu, Zn; pmdc pyrimidine-4,6-dicarboxylate), we have combined ab initio X-ray powder diffraction methods with in situ thermodiffractometry and thermal analyses to characterize the selective and reversible transformation of the [M(pmdc)(H2O)2]\ub7H2O compounds (M Fe, Co, Ni, Cu) into the bis-hydrated [M(pmdc)(H2O)2] counterparts by moderate heating, which is followed by an irreversible transformation into two-dimensional (2-D) anhydrous species. The structural features of the transient bis-hydrated species and of the completely dehydrated one are described for M Cu. Remarkably, the \ufb01rst dehydration process does not alter the 1-D nature of the [M(pmdc)(H2O)2] chains; on the contrary, the second dehydration gives rise to the loss of the axially coordinated water molecules with a concomitant condensation of the 1-D chains into 2-D layers through ancillary carboxylate bridging groups. The magnetic properties of the anhydrous [M(pmdc)] species (M Co, Ni, Cu) have been investigated, showing that these phases behave as 1-D antiferromagnets with interchain interactions. Notably, in the case of the [Ni(pmdc)] system, a weak ferromagnetic ordering, arising from a spin canting phenomenon with a blocking temperature of 13 K, is observed

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics