5 research outputs found

    Distinct mechanism of action for antitumoral neutral cyclometalated Pt(II)-complexes bearing antifungal imidazolyl-based drugs

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    Three neutral Pt(II) complexes containing 1-Methylimidazole and the antifungal imidazolyl drugs Clotrimazole and Bifonazole have been prepared. The general formula of the new derivatives is [Pt(κ2-(C^N)Cl(L)], where C^N stands for ppy = 2-phenylpyridinate, and L = 1-Methylimidazole (MeIm) for [Pt-MeIm]; L = Clotrimazole (CTZ) for [Pt-CTZ] and L = Bifonazole (BFZ) for [Pt-BFZ]). The complexes have been completely characterized in solution and the crystal structures of [Pt-BFZ] and [Pt-CTZ] have been resolved. Complexes [Pt-MeIm] and [Pt-BFZ] present higher cytotoxicity than cisplatin in SW480 (colon adenocarcinoma), A549 (lung adenocarcinoma) and A2780 (ovarian cancer) cell lines. [Pt-MeIm] shows the highest accumulation in A549 cells, in agreement with its inability to interact with serum albumin. By contrast, [Pt-CTZ] and [Pt-BFZ] interact with serum proteins, a fact that reduces their bioavailability. The strongest interaction with bovine serum albumin (BSA) is found for [Pt-BFZ], which is the least internalized inside the cells. All the complexes are able to covalently interact with DNA. The most cytotoxic complexes, [Pt-MeIm] and [Pt-BFZ] induce cellular accumulation in G0/G1 and apoptosis by a similar pathway, probably involving a reactive oxygen species (ROS) generation mechanism. [Pt-BFZ] turns out to be the most efficient complex regarding ROS generation and causes mitochondrial membrane depolarization, whereas [Pt-MeIm] induces the opposite effect, hyperpolarization of the mitochondrial membrane. On the contrary, the least cytotoxic complex, [Pt-CTZ] cannot block the cell cycle or generate ROS and the mechanism by which it induces apoptosis could be a different one.La Caixa Foundation (LCF/PR/PR12/11070003), Consejería de Educación-Junta de Castilla y León-FEDER (BU042U16-BU305P18), Ministerio de Ciencia, Innovación y Universidades (RTI2018-102040-B-100). M.V. is grateful for the financial support received from the Consejería de Educación-Junta de Castilla y León-FEDER (BU042U16-BU305P18)

    The effect of halogenation of salicylaldehyde on the antiproliferative activities of {Δ/Λ-[Ru(bpy)2(X,Y-sal)]BF4} complexes†

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    Ru(II) polypyridyl complexes are widely used in biological fields, due to their physico-chemical and photophysical properties. In this paper, a series of new chiral Ru(II) polypyridyl complexes (1–5) with the general formula {Δ/Λ-[Ru(bpy)2(X,Y-sal)]BF4} (bpy = 2,2′-bipyridyl; X,Y-sal = 5-bromosalicylaldehyde (1), 3,5-dibromosalicylaldehyde (2), 5-chlorosalicylaldehyde (3), 3,5-dichlorosalicylaldehyde (4) and 3-bromo-5-chlorosalicylaldehy (5)) were synthesized and characterized by elemental analysis, FT-IR, and 1H/13C NMR spectroscopy. Also, the structures of complexes 1 and 5 were determined by X-ray crystallography; these results showed that the central Ru atom adopts a distorted octahedral coordination sphere with two bpy and one halogen-substituted salicylaldehyde. DFT and TD-DFT calculations have been performed to explain the excited states of these complexes. The singlet states with higher oscillator strength are correlated with the absorption signals and are mainly described as 1MLCT from the ruthenium centre to the bpy ligands. The lowest triplet states (T1) are described as 3MLCT from the ruthenium center to the salicylaldehyde ligand. The theoretical results are in good agreement with the observed unstructured band at around 520 nm for complexes 2, 4 and 5. Biological studies on human cancer cells revealed that dihalogenated ligands endow the Ru(II) complexes with enhanced cytotoxicity compared to monohalogenated ligands. In addition, as far as the type of halogen is concerned, bromine is the halogen that provides the highest cytotoxicity to the synthesized complexes. All complexes induce cell cycle arrest in G0/G1 and apoptosis, but only complexes bearing Br are able to provoke an increase in intracellular ROS levels and mitochondrial dysfunction.Research Council of the University of Isfahan (Iran) for financial support of this work. Financial support from La Caixa Foundation (LCF/PR/PR12/11070003), Ministerio de Ciencia, Innovación y Universidades (Grant PID2019-111215RB-I00 and RTI2018-102040-B-100) and Consejería de Educación, Junta de Castilla y León, FEDER (BU305P18) is gratefully acknowledged

    Effectiveness of 23-valent pneumococcal polysaccharide vaccination in preventing community-acquired pneumonia hospitalization and severe outcomes in the elderly in Spain

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    Pneumococcal pneumonia is a serious cause of morbidity and mortality in the elderly, but investigation of the etiological agent of community-acquired pneumonia (CAP) is not possible in most hospitalized patients. The aim of this study was to estimate the effect of pneumococcal polysaccharide vaccination (PPSV23) in preventing CAP hospitalization and reducing the risk of intensive care unit admission (ICU) and fatal outcomes in hospitalized people aged ≥65 years. We made a multicenter case-control study in 20 Spanish hospitals during 2013-2014 and 2014-2015. We selected patients aged 65 years hospitalized with a diagnosis of pneumonia and controls matched by sex, age and date of hospitalization. Multivariate analysis was performed using conditional logistic regression to estimate vaccine effectiveness and unconditional logistic regression to evaluate the reduction in the risk of severe and fatal outcomes. 1895 cases and 1895 controls were included; 13.7% of cases and 14.4% of controls had received PPSV23 in the last five years. The effectiveness of PPSV23 in preventing CAP hospitalization was 15.2% (95% CI -3.1-30.3). The benefit of PPSV23 in avoiding ICU admission or death was 28.1% (95% CI -14.3-56.9) in all patients, 30.9% (95% CI -32.2-67.4) in immunocompetent patients and 26.9% (95% CI -38.6-64.8) in immunocompromised patients. In conclusion, PPSV23 showed a modest trend to avoidance of hospitalizations due to CAP and to the prevention of death or ICU admission in elderly patients hospitalized with a diagnosis of CAP

    Psicología de las organizaciones y del trabajo. Apuestas de investigación II

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    El presente volumen condensa y sintetiza lo que va siendo contemporáneamente la POT colombiana, en particular, y latinoamericana, en general, que aparece como un reflejo y una adaptación de la que se está desarrollando globalmente según cánones dictados desde otras latitudes socioeconómicas, políticas y culturales, pero también como reacción a ella y como autoafirmación. Ello no constituye un ejemplar de texto anticolonial, sino más bien un manifiesto antietnocéntrico al presentar e interpretar la realidad investigada en el marco de sus propios parámetros socioculturales, sin que estos sean considerados necesariamente claves universales para la comprensión de otras realidades ajenas y exóticas. Y esta es una de sus principales contribuciones generales, porque marca un estilo distinto de hacer POT al enfatizar el aspecto idiosincrático de los fenómenos y procesos de que se ocupa y haciéndolo así, señala un horizonte que no deben perder de vista la disciplina y la profesión, si no quieren repetir viejos errores de su pasado reciente derivados de la minimización de la relatividad histórico-cultural de su campo y su objeto. A escala global y local, resta un largo camino por progresar hacia una POT con mayor fundamentación epistemológica, más articulación interdisciplinaria y multiprofesional, relevancia social, elaboración teórica, calidad y diversidad metodológicas y reflexividad autocrítica que resitúe en el centro del quehacer científico y profesional el marco de referencia axiológico, étho-politico y deontológico. Este libro es un paso significativo en esta dirección.Universidad de San Buenaventura - Cal
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