Lead encapsulation by a golden clamp through multiple electrostatic, metallophilic, hydrogen bonding and weak interactions.

The structure of the complex [{Pb(HBpz3)}{Au3(o-C6BrF4)3(HBpz3)}] consists of a host-guest heterometallic system built up through a plethora of interactions including electrostatic, metallophilic, H-bonding, AuBr or weak CC or PbBr contacts. Computational studies show that the dispersive interactions are responsible for the attraction of the Pb(ii) cationic moiety within the basket-like trinuclear Au(i) fragment, whereas the ionic component of the interaction placed at the rings produces a molecular clamp.

[Telomeres and diet quality]. / Telómeros y calidad de la dieta.

BACKGROUND: Few studies have evaluated the relationship between diet quality and telomere integrity in humans. Telomeres are regions of non-coding DNA localized at the end of each chromosome whose length, in addition to indicating life expectancy, indicates an overall health status. The objective of this systematic review is to compile the existing evidence on the relationship between telomere length and diet quality to further explore the impact that some nutrients, foods and dietary patterns may have on telomere homeostasis and therefore, in precision nutrition strategies. MATERIAL AND METHODS: A bibliographic review was performed in the PubMed database to identify published articles (in English or Spanish) until December 2016 that met the following criteria: included human subjects; cross-sectional studies; case-control studies; prospective cohort studies or intervention studies; evaluating the relationship of nutrients, foods or dietary patterns on telomere integrity. The search strategy included the following keywords: nutrients or food OR food groups OR diet OR dietary pattern OR eating pattern OR dietary habits OR diet type AND telomere attrition OR telomere length. In total, 19 cross-sectional studies, five case-control studies, five prospective cohort studies, and two intervention studies were included, including those articles that were found for being listed in other publications. RESULTS: Positive associations were found between telomere length and adherence to the Mediterranean diet and consumption of vegetables and fruits. The results observed for other nutrients, foods or dietary patterns were incoherent although it seems that processed meats, cereals, alcohol and sweetened beverages could be associated with shorter telomeres. CONCLUSIONS: Dietary intervention, and in particular the promotion of a Mediterranean-style diet, may play a role in the protection of telomere integrity.

Telómeros y calidad de la dieta / Telomeres and diet quality

Fundamento: existen pocos estudios que hayan evaluado la relación entre la calidad de la dieta y la integridad telómerica en humanos. Los telómeros son regiones de ADN no codificante que se encuentran en los extremos de los cromosomas, cuya longitud además de indicar la esperanza de vida, indica el estado global de salud. El objetivo de la presente revisión sistemática es recopilar la evidencia existente sobre la relación entre la longitud de los telómeros y la calidad de la dieta para conocer el impacto que algunos nutrientes, alimentos y patrones dietéticos pueden tener sobre la homeostasis telomérica y por lo tanto, sobre la salud en general. Material y métodos: se realizó una revisión bibliográfica en la base de datos PubMed para identificar los artículos publicados (en inglés o español) hasta diciembre de 2016 que cumplían los siguientes criterios: incluían sujetos humanos; eran estudios transversales; estudios de casos y controles; estudios de cohortes prospectivos o estudios de intervención; que evaluaban la relación de los nutrientes, alimentos o patrones dietéticos con la longitud de los telómeros. La estrategia de búsqueda incluía las siguientes palabras clave: nutrients or food OR food groups OR diet OR dietary pattern OR eating pattern OR dietary habits OR diet type AND telomere attrition OR telomere length. En total, se incluyeron 19 estudios transversales, cinco estudios de casos y controles, cinco estudios de cohortes prospectivos y dos estudios de intervención, incluyendo aquellos artículos que se encontraron por listas de referencias de otras publicaciones. Resultados: se encontraron asociaciones positivas entre la longitud de los telómeros y la adherencia a la dieta mediterránea y el consumo de verduras y frutas. Los resultados obtenidos para otros nutrientes, alimentos o patrones dietéticos fueron incoherentes, aunque parece que las carnes procesadas, los cereales, el alcohol y las bebidas endulzadas podrían estar asociados con telómeros más cortos. Conclusiones: la intervención dietética, y en particular la promoción de una dieta de estilo mediterráneo, podría desempeñar un papel en la protección de la integridad telomérica (AU)

Background: Few studies have evaluated the relationship between diet quality and telomere integrity in humans. Telomeres are regions of non-coding DNA localized at the end of each chromosome whose length, in addition to indicating life expectancy, indicates an overall health status. The objective of this systematic review is to compile the existing evidence on the relationship between telomere length and diet quality to further explore the impact that some nutrients, foods and dietary patterns may have on telomere homeostasis and therefore, in precision nutrition strategies. Material and methods: A bibliographic review was performed in the PubMed database to identify published articles (in English or Spanish) until December 2016 that met the following criteria: included human subjects; cross-sectional studies; case-control studies; prospective cohort studies or intervention studies; evaluating the relationship of nutrients, foods or dietary patterns on telomere integrity. The search strategy included the following keywords: nutrients or food OR food groups OR diet OR dietary pattern OR eating pattern OR dietary habits OR diet type AND telomere attrition OR telomere length. In total, 19 cross-sectional studies, five case-control studies, five prospective cohort studies, and two intervention studies were included, including those articles that were found for being listed in other publications. Results: Positive associations were found between telomere length and adherence to the Mediterranean diet and consumption of vegetables and fruits. The results observed for other nutrients, foods or dietary patterns were incoherent although it seems that processed meats, cereals, alcohol and sweetened beverages could be associated with shorter telomeres. Conclusions: Dietary intervention, and in particular the promotion of a Mediterranean-style diet, may play a role in the protection of telomere integrity (AU)

New Insights into the Au(I)···Pb(II) Closed-Shell Interaction: Tuning of the Emissive Properties with the Intermetallic Distance.

Reaction of [Au2Ag2R4(Et2O)2] (R = C6Cl2F3- or C6F5-) with [Pb{HB(pz)3}]Cl in a 1:2 molar ratio led to complexes [AuPb{HB(pz)3}R2] (R = C6Cl2F3- (2) or C6F5- (3)) through transmetalation reactions. The crystal structures of these complexes display unsupported Au(I)···Pb(II) interactions of 3.0954(4) (2) and 3.2778(4) (3) Å, together with one (2) or two (3) F···Pb weak contacts. These intermetallic distances are compared to the shortest one found for the previously reported complex [Pb{HB(pz)3}Au(C6Cl5)2] (1) of 3.0494(4) (1) Å, showing a clear dependence with the donating properties of the different aurate units. The complexes are emissive in the solid state due to charge transfer transitions associated with the presence of Au(I)···Pb(II) interactions, in which the intermetallic distance plays a crucial role. Density functional theory and time-dependent density functional theory calculations support the assignment of the luminescent properties of the complexes. Ab initio Hartree-Fock and MP2 calculations on model systems of complexes 2 and 3 show the presence of strong Au(I)···Pb(II) closed-shell interactions of an ionic plus dispersive nature together with weak F···Pb contacts of a dispersive origin in the case of complexes 2 and 3.

Double Jahn-Teller Distortion in AuGe Complexes Leading to a Dual Blue-Orange Emission.

Invited for this month's cover are collaborators from the group of José M. López-de-Luzuriaga at Universidad de la Rioja, Spain and researchers from University of Helsinki, Finland. The cover picture shows a photograph of a gold-germanium complex that has two emission modes corresponding to two independent triplet excited states. Read the full text of the article at 10.1002/cplu.201500337.

Double Jahn-Teller Distortion in AuGe Complexes Leading to a Dual Blue-Orange Emission.

The tetrahedral AuI complexes [Au(GeCl3 )L3 ] (L=PMe3  (1), PMe2 Ph (2), PMePh2  (3), PPh3  (4)) were synthesized by in situ treatment of the [Au(GeCl3 )(tht)] complex with three equivalents of the corresponding tertiary phosphine. The crystal structures of complexes 1 and 3 have been determined through X-ray diffraction studies and show [GeCl3 ]- fragments bonded to the corresponding [Au(PR3 )3 ]+ units through covalent bonds, leading to a tetrahedral coordination environment for gold. Complexes 3 and 4 show dual phosphorescence in the solid state at 77 K and, in the case of complex 4, an interesting room-temperature mechanochromism effect is observed. Correlated MP2, SCS-MP2, SCS-CC2, and ONIOM MP2/UFF calculations suggest the existence of two largely distorted and thermally connected triplet excited states (T1 and T2 ) for a model system of complex 4. The AuP3 + moiety can be distorted in two different planes leading to the two triplet excited states T1 and T2 , leaving the GeCl3 - unit almost unaltered. The emissions of these phosphorescent AuI GeII complexes is mainly ascribed to a metal (gold)-centered (3 MC) transition with some contribution from the [GeCl3 ]- fragments.

The gold(i)···lead(ii) interaction: a relativistic connection.

The crystal structure of complex [Pb{HB(pz)3}Au(C6Cl5)2] 1 displays an unsupported Au(i)···Pb(ii) interaction. This complex emits at 480 nm in the solid state due to an aurate(i) to lead(ii) charge transfer, in which the existence of a metallophilic interaction is a pre-requisite. Ab initio calculations show a very strong Au(i)···Pb(ii) closed-shell interaction of -390 kJ mol-1, which has an ionic plus a dispersive (van der Waals) nature strengthened by large relativistic effects (>17%).

Double Photoinduced Jahn-Teller Distortion of Tetrahedral AuI SnII Complexes.

Tetrahedral AuI complexes [L3 Au(SnCl3 )] (L=PMe3 (1), PMe2 Ph (2), PMePh2 (3), and PPh3 (4)) were prepared by treatment of the [(tht)Au(SnCl3 )] (tht=tetrahydrothiophene) complex with three equivalents of the corresponding tertiary phosphine. The crystal structures of complexes 1-4 have been determined through X-ray diffraction studies showing, in all cases, [SnCl3 ]- fragments covalently bonded to the corresponding [Au(PR3 )3 ]+ units, which leads to a tetrahedral coordination environment for gold. Complexes 3 and 4 show phosphorescence in the solid state at room temperature and 77 K that is largely redshifted relative to the free [Au(PR3 )3 ]+ and [SnCl3 ]- counterparts. Correlated MP2, SCS-MP2, and ONIOM MP2/UFF calculations suggest a largely distorted lower triplet excited state (T1 ) for each model system. The AuP3 + moiety is distorted leading to a T-shape, whereas the SnCl3 - unit is left almost unaltered. Molecular orbital and population analysis suggest that the emission of these tetrahedral AuI complexes arises from a 3 MC transition slightly perturbed by the SnCl3 - fragment.