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1.
Inorg Chem ; 62(15): 5961-5971, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37010818

RESUMEN

The divergent reactivity of the cationic iridium complex [(η5-C5Me5)IrCl(PMe2ArDipp2)]+ (ArDipp2 = C6H3-2,6-(C6H3-2,6-iPr2)2) toward organolithium and Grignard reagents is described. The noninnocent behavior of the Cp* ligand, a robust spectator in the majority of stoichiometric and catalytic reactions, was manifested by its unforeseen electrophilic character toward organolithium reagents LiMe, LiEt, and LinBu. In these unconventional transformations, the metal center is only indirectly involved by means of the Ir(III)/Ir(I) redox cycle. In the presence of less nucleophilic organolithium reagents, the Cp* ligand also exhibits noninnocent behavior undergoing facile deprotonation, which is also concomitant with the reduction of the metal center. In turn, the weaker alkylating agents EtMgBr and MeMgBr effectively achieve the alkylation of the metal center. These reactive iridium(III) alkyls partake in subsequent reactions: while the ethyl complex undergoes ß-H elimination, the methyl derivative releases methane by a remote C-H bond activation. Computational studies, including the quantum theory of atoms in molecules (QTAIM), support that the preferential activation of the non-benzylic C-H bonds takes place via sigma-bond metathesis.

2.
J Sci Food Agric ; 103(15): 7506-7516, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37402233

RESUMEN

BACKGROUND: The main aim of this 2-year non-randomized parallel controlled clinical pilot trial was to evaluate the long-term effect of a moderate daily intake of beer (with and without alcohol) on cardiovascular health in postmenopausal women. A total of 34 participants were grouped into three study arms: 16 were administered alcoholic beer, 6 consumed non-alcoholic beer, and 12 were in the control group. Changes in glucose metabolism, lipid profile, liver enzymes, anthropometric measurements, body composition, and blood pressure variables were monitored. Data on medical history, diet, and exercise were collected, and gustatory capacities were determined. RESULTS: Moderate consumption of beer, both alcoholic and non-alcoholic, seemed to have positive effects on biochemical indicators of cardiovascular health in postmenopausal women, with 660 mL day-1 of non-alcoholic beer reducing low-density lipoprotein cholesterol blood levels, and 330 mL day-1 of alcoholic beer increasing high-density lipoprotein cholesterol. The evolution of changes in android and gynoid fat percentage and their ratio differed significantly between study groups, which was attributable to either the interventions or the disparity between groups regarding the time elapsed since menopause onset. Iso-α-acids recognition threshold could be involved in intervention group election, whereas the sensory phenotypes studied were not associated with alcohol drinking frequency. CONCLUSIONS: Moderate beer consumption was found to improve the lipid profile of postmenopausal women, although their effects in preventing cardiometabolic alterations deserve further research (trial registration number: ISRCTN13825020; https://doi.org/10.1186/ISRCTN13825020). © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Cerveza , Etanol , Femenino , Humanos , Consumo de Bebidas Alcohólicas , Cerveza/análisis , HDL-Colesterol , Posmenopausia
3.
Inorg Chem ; 61(43): 16963-16970, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36260749

RESUMEN

Electrocatalyst design and optimization strategies continue to be an active area of research interest for the applied use of renewable energy resources. The electrocatalytic conversion of carbon dioxide (CO2) is an attractive approach in this context because of the added potential benefit of addressing its rising atmospheric concentrations. In previous experimental and computational studies, we have described the mechanism of the first molecular Cr complex capable of electrocatalytically reducing CO2 to carbon monoxide (CO) in the presence of an added proton donor, which contained a redox-active 2,2'-bipyridine (bpy) fragment, CrN2O2. The high selectivity for CO in the bpy-based system was dependent on a delocalized CrII(bpy•-) active state. Subsequently, we became interested in exploring how expanding the polypyridyl ligand core would impact the selectivity and activity during electrocatalytic CO2 reduction. Here, we report a new CrN3O catalyst, Cr(tpytbupho)Cl2 (1), where 2-(2,2':6',2″-terpyridin-6-yl)-4,6-di-tert-butylphenolate = [tpytbupho]-, which reduces CO2 to CO with almost quantitative selectivity via a different mechanism than our previously reported Cr(tbudhbpy)Cl(H2O) catalyst. Computational analyses indicate that, although the stoichiometry of both reactions is identical, changes in the observed rate law are the combined result of a decrease in the intrinsic ligand charge (L3X vs L2X2) and an increase in the ligand redox activity, which result in increased electronic coupling between the doubly reduced tpy fragment of the ligand and the CrII center. The strong electronic coupling enhances the rate of protonation and subsequent C-OH bond cleavage, resulting in CO2 binding becoming the rate-determining step, which is an uncommon mechanism during protic CO2 reduction.

4.
Angew Chem Int Ed Engl ; 61(1): e202109645, 2022 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-34695281

RESUMEN

The electrocatalytic reduction of CO2 is an appealing method for converting renewable energy sources into value-added chemical feedstocks. We report a co-electrocatalytic system for the reduction of CO2 to CO comprised of a molecular Cr complex and dibenzothiophene-5,5-dioxide (DBTD) as a redox mediator, which achieves high activity (TOF=1.51-2.84×105  s-1 ) and quantitative selectivity. Under aprotic or protic conditions, DBTD produces a co-electrocatalytic response with 1 by coordinating trans to the site of CO2 binding and mediating electron transfer from the electrode with quantitative efficiency for CO. This assembly is reliant on through-space electronic conjugation between the π frameworks of DBTD and the bpy fragment of the catalyst ligand, with contributions from dispersive interactions and weak sulfone coordination.

5.
J Am Chem Soc ; 143(6): 2509-2522, 2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33544575

RESUMEN

Organometallic gold complexes are used in a range of catalytic reactions, and they often serve as catalyst precursors that mediate C-C bond formation. In this study, we investigate C-C coupling to form ethane from various phosphine-ligated gem-digold(I) methyl complexes including [Au2(µ-CH3)(PMe2Ar')2][NTf2], [Au2(µ-CH3)(XPhos)2][NTf2], and [Au2(µ-CH3)(tBuXPhos)2][NTf2] {Ar' = C6H3-2,6-(C6H3-2,6-Me)2, C6H3-2,6-(C6H2-2,4,6-Me)2, C6H3-2,6-(C6H3-2,6-iPr)2, or C6H3-2,6-(C6H2-2,4,6-iPr)2; XPhos = 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl; tBuXPhos = 2-di-tert-butylphosphino-2',4',6'-triisopropylbiphenyl; NTf2 = bis(trifluoromethyl sulfonylimide)}. The gem-digold methyl complexes are synthesized through reaction between Au(CH3)L and Au(L)(NTf2) {L = phosphines listed above}. For [Au2(µ-CH3)(XPhos)2][NTf2] and [Au2(µ-CH3)(tBuXPhos)2][NTf2], solid-state X-ray structures have been elucidated. The rate of ethane formation from [Au2(µ-CH3)(PMe2Ar')2][NTf2] increases as the steric bulk of the phosphine substituent Ar' decreases. Monitoring the rate of ethane elimination reactions by multinuclear NMR spectroscopy provides evidence for a second-order dependence on the gem-digold methyl complexes. Using experimental and computational evidence, it is proposed that the mechanism of C-C coupling likely involves (1) cleavage of [Au2(µ-CH3)(PMe2Ar')2][NTf2] to form Au(PR2Ar')(NTf2) and Au(CH3)(PMe2Ar'), (2) phosphine migration from a second equivalent of [Au2(µ-CH3)(PMe2Ar')2][NTf2] aided by binding of the Lewis acidic [Au(PMe2Ar')]+, formed in step 1, to produce [Au2(CH3)(PMe2Ar')][NTf2] and [Au2(PMe2Ar')]+, and (3) recombination of [Au2(CH3)(PMe2Ar')][NTf2] and Au(CH3)(PMe2Ar') to eliminate ethane.

6.
Inorg Chem ; 60(6): 3635-3650, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33657314

RESUMEN

A variety of molecular transition metal-based electrocatalysts for the reduction of carbon dioxide (CO2) have been developed to explore the viability of utilization strategies for addressing its rising atmospheric concentrations and the corresponding effects of global warming. Concomitantly, this approach could also meet steadily increasing global energy demands for value-added carbon-based chemical feedstocks as nonrenewable petrochemical resources are consumed. Reports on the molecular electrocatalytic reduction of CO2 mediated by chromium (Cr) complexes are scarce relative to other earth-abundant transition metals. Recently, our group reported a Cr complex that can efficiently catalyze the reduction of CO2 to carbon monoxide (CO) at low overpotentials. Here, we present new mechanistic insight through a computational (density functional theory) study, exploring the origin of kinetic selectivity, relative energetic positioning of the intermediates, speciation with respect to solvent coordination and spin state, as well as the role of the redox-active bipyridine moiety. Importantly, these studies suggest that under certain reducing conditions, the formation of bicarbonate could become a competitive reaction pathway, informing new areas of interest for future experimental studies.

7.
Angew Chem Int Ed Engl ; 59(47): 20863-20867, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33448577

RESUMEN

The use of cyclopentadienyl ligands in organometallic chemistry and catalysis is ubiquitous, mostly due to their robust spectator role. Nonetheless, increasing examples of non-innocent behaviour are being documented. Here, we provide evidence for reversible intramolecular C-H activation at one methyl terminus of C5Me5 in [(η-C5Me5)Rh(PMe3)2] to form a new Rh-H bond, a process so far restricted to early transition metals. Experimental evidence was acquired from bimetallic rhodium/gold structures in which the gold center binds either to the rhodium atom or to the activated Cp* ring. Reversibility of the C-H activation event regenerates the RhI and AuI monometallic precursors, whose cooperative reactivity towards polar E-H bonds (E=O, N), including the N-H bonds in ammonia, can be understood in terms of bimetallic frustration.

8.
J Am Chem Soc ; 141(6): 2205-2210, 2019 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-30682245

RESUMEN

C-H bond activation at cationic [(η5-C5Me5)Ir(PMe2Ar')] centers is described, where PMe2Ar' are the terphenyl phosphine ligands PMe2ArXyl2 and PMe2ArDipp2. Different pathways are defined for the conversion of the five-coordinate complexes [(η5-C5Me5)IrCl(PMe2Ar')]+, 2(Xyl)+ and 2(Dipp)+, into the corresponding pseudoallyls 3(Xyl)+ and 3(Dipp)+. In the absence of an external Brønsted base, electrophilic, remote ζ C-H activation takes place, for which the participation of dicationic species, [(η5-C5Me5)Ir(PMe2Ar')]2+, is proposed. When NEt3 is present, the PMe2ArDipp2 system is shown to proceed via 4(Dipp)+ as an intermediate en route to the thermodynamic, isomeric product 3(Dipp)+. This complex interconversion involves a non-innocent C5Me5 ligand, which participates in C-H and C-C bond formation and cleavage. Remarkably, the conversion of 4(Dipp)+ to 3(Dipp)+ also proceeds in the solid state.

9.
J Cell Sci ; 130(5): 950-962, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28104814

RESUMEN

Cell-extracellular-matrix adhesion is mediated by cell receptors, mainly integrins and transmembrane proteoglycans, which can functionally interact. How these receptors are regulated and coordinated is largely unknown. We show that the conserved transmembrane Drosophila proteoglycan Kon-tiki (Kon, also known as Perdido) interacts with the αPS2ßPS integrin (αPS2 is encoded by inflated and ßPS by myospheroid) to mediate muscle-tendon adhesion. kon and inflated double mutant embryos show a synergistic increase in muscle detachment. Furthermore, Kon modulates αPS2ßPS signaling at the muscle attachment, since phosphorylated Fak is reduced in kon mutants. This reduction in integrin signaling can be rescued by the expression of a truncated Kon protein containing its transmembrane and extracellular domains, suggesting that these domains are sufficient to mediate this signaling. We show that these domains are sufficient to properly localize the αPS2ßPS ligand, Thrombospondin, to the muscle attachment, and to partially rescue Kon-dependent muscle-tendon adhesion. We propose that Kon can engage in a protein complex with αPS2ßPS and enhance integrin-mediated signaling and adhesion by recruiting its ligand, which would increase integrin-binding affinity to the extracellular matrix, resulting in the consolidation of the myotendinous junction.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Cadenas alfa de Integrinas/metabolismo , Músculos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Tendones/metabolismo , Trombospondinas/metabolismo , Animales , Adhesión Celular , Línea Celular , Proteínas de Drosophila/química , Drosophila melanogaster/embriología , Embrión no Mamífero/metabolismo , Epistasis Genética , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Ligandos , Proteínas del Tejido Nervioso/química , Fosforilación , Dominios Proteicos , Subunidades de Proteína/metabolismo , Transducción de Señal , Relación Estructura-Actividad
10.
Chemistry ; 25(1): 260-272, 2019 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-30290026

RESUMEN

The experimental and computational characterization of a series of dialkylterphenyl phosphines, PR2 Ar' is described. The new P-donors comprise five compounds of general formula PR2 Ar Dtbp 2 (R=Me, Et, iPr, c-C5 H9 and c-C6 H11 ); Ar Dtbp 2 = 2,6-C6 H3 -(3,5-C6 H3 -(CMe3 )2 )2 ), and another five PR2 Ar' phosphines containing the bulky alkyl groups iPr, c-C5 H9 or c-C6 H11 , in combination with Ar'=Ar Xyl 2 , Ar Xyl ' 2 , or Ar Ph 2 (L1-L10). Steric and electronic parameters have been determined computationally and from IR and X-ray data obtained for the phosphines and for some derivatives, including tricarbonyl and dicarbonyl nickel complexes, Ni(CO)3 (PR2 Ar') and Ni(CO)2 (PR2 Ar'). In the solid state, the free phosphines PR2 Ar' adopt one of the three possible structures formally related by rotation around the Cipso -P bond. Details on their relative energies and on the influence of the free phosphine structure on its coordination chemistry towards Ni(CO)n (n = 2, 3) fragments has been obtained by experimental and computational methods.


Asunto(s)
Complejos de Coordinación/síntesis química , Compuestos Organometálicos/química , Fosfinas/química , Complejos de Coordinación/química , Cristalografía por Rayos X , Conformación Molecular , Espectrofotometría Infrarroja
11.
J Nutr ; 149(11): 1920-1929, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31334554

RESUMEN

BACKGROUND: Adherence to a Mediterranean diet (MedDiet) is thought to reduce liver steatosis. OBJECTIVES: To explore the associations with liver steatosis of 3 different diets: a MedDiet + extra-virgin olive oil (EVOO), MedDiet + nuts, or a control diet. METHODS: This was a subgroup analysis nested within a multicenter, randomized, parallel-group clinical trial, PREvención con DIeta MEDiterránea (PREDIMED trial: ISRCTN35739639), aimed at assessing the effect of a MedDiet on the primary prevention of cardiovascular disease. One hundred men and women (mean age: 64 ± 6 y), at high cardiovascular risk (62% with type 2 diabetes) from the Bellvitge-PREDIMED center were randomly assigned to a MedDiet supplemented with EVOO, a MedDiet supplemented with mixed nuts, or a control diet (advice to reduce all dietary fat). No recommendations to lose weight or increase physical activity were given. Main measurements were the percentage of liver fat and the diagnosis of steatosis, which were determined by NMR imaging. The association of diet with liver fat content was analyzed by bivariate analysis after a median follow-up of 3 y. RESULTS: Baseline adiposity and cardiometabolic risk factors were similar among the 3 treatment arms. At 3 y after the intervention hepatic steatosis was present in 3 (8.8%), 12 (33.3%), and 10 (33.3%) of the participants in the MedDiet + EVOO, MedDiet + nuts, and control diet groups, respectively (P = 0.027). Respective mean values of liver fat content were 1.2%, 2.7%, and 4.1% (P = 0.07). A tendency toward significance was observed for the MedDiet + EVOO group compared with the control group. Median values of urinary 12(S)-hydroxyeicosatetraenoic acid/creatinine concentrations were significantly (P = 0.001) lower in the MedDiet + EVOO (2.3 ng/mg) than in the MedDiet + nuts (5.0 ng/mg) and control (3.9 ng/mg) groups. No differences in adiposity or glycemic control changes were seen between groups. CONCLUSIONS: An energy-unrestricted MedDiet supplemented with EVOO, a food with potent antioxidant and anti-inflammatory properties, is associated with a reduced prevalence of hepatic steatosis in older individuals at high cardiovascular risk.


Asunto(s)
Dieta Mediterránea , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Aceite de Oliva/administración & dosificación , Anciano , Enfermedades Cardiovasculares/prevención & control , Dieta con Restricción de Grasas , Femenino , Humanos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Nueces , Prevalencia , Prevención Primaria , Factores de Riesgo , España/epidemiología
14.
J Cell Sci ; 127(Pt 14): 3162-73, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24794494

RESUMEN

Muscle differentiation requires the assembly of high-order structures called myofibrils, composed of sarcomeres. Even though the molecular organization of sarcomeres is well known, the mechanisms underlying myofibrillogenesis are poorly understood. It has been proposed that integrin-dependent adhesion nucleates myofibrils at the periphery of the muscle cell to sustain sarcomere assembly. Here, we report a role for the gene perdido (perd, also known as kon-tiki, a transmembrane chondroitin proteoglycan) in myofibrillogenesis. Expression of perd RNAi in muscles, prior to adult myogenesis, can induce misorientation and detachment of Drosophila adult abdominal muscles. In comparison to controls, perd-depleted muscles contain fewer myofibrils, which are localized at the cell periphery. These myofibrils are detached from each other and display a defective sarcomeric structure. Our results demonstrate that the extracellular matrix receptor Perd has a specific role in the assembly of myofibrils and in sarcomeric organization. We suggest that Perd acts downstream or in parallel to integrins to enable the connection of nascent myofibrils to the Z-bands. Our work identifies the Drosophila adult abdominal muscles as a model to investigate in vivo the mechanisms behind myofibrillogenesis.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila/crecimiento & desarrollo , Proteínas de la Membrana/metabolismo , Proteínas Musculares/metabolismo , Proteoglicanos/metabolismo , Sarcómeros/fisiología , Animales , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de la Membrana/genética , Desarrollo de Músculos , Sarcómeros/metabolismo
15.
Chem Sci ; 15(18): 6842-6852, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38725514

RESUMEN

End-on binding of dinitrogen to low valent metal centres is common in transition metal chemistry but remains extremely rare in f-elements chemistry. In particular, heterobimetallic end-on N2 bridged complexes of lanthanides are unprecedented despite their potential relevance in catalytic reduction of dinitrogen. Here we report the synthesis and characterization of a series of N2 bridged heterobimetallic complexes of U(iii), Ln(iii) and Ln(ii) which were prepared by reacting the Fe dinitrogen complex [Fe(depe)2(N2)] (depe = 1,2-bis(diethylphosphino)-ethane), complex A with [MIII{N(SiMe3)2}3] (M = U, Ce, Sm, Dy, Tm) and [LnII{N(SiMe3)2}2], (Ln = Sm, Yb). Despite the lack of reactivity of the U(iii), Ln(iii) and Ln(ii) amide complexes with dinitrogen, the end-on dinitrogen bridged heterobimetallic complexes [{Fe(depe)2}(µ-η1:η1-N2)(M{N(SiMe3)2}3)], 1-M (M = U(iii), Ce(iii), Sm(iii), Dy(iii) and Tm(iii)), [{Fe(depe)2}(µ-η1:η1-N2)(Ln{N(SiMe3)2}2)], 1*-Ln (Ln = Sm(ii), Yb(ii)) and [{Fe(depe)2(µ-η1:η1-N2)}2{SmII{N(SiMe3)2}2}], 3 could be prepared. The synthetic method used here allowed to isolate unprecedented end-on bridging N2 complexes of divalent lanthanides which provide relevant structural models for the species involved in the catalytic reduction of dinitrogen by Fe/Sm(ii) systems. Computational studies showed an essentially electrostatic interaction of the end-on bridging N2 with both Ln(iii) and Ln(ii) complexes with the degree of N2 activation correlating with their Lewis acidity. In contrast, a back-bonding covalent contribution to the U(iii)-N2Fe bond was identified by computational studies. Computational studies also suggest that end-on binding of N2 to U(iii) and Ln(ii) complexes is favoured for the iron-bound N2 compared to free N2 due to the higher N2 polarization.

16.
Int J Ment Health Nurs ; 33(1): 134-142, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37743558

RESUMEN

The therapeutic relationship (TR) is essential in mental health nursing care and plays a fundamental role in the understanding and treatment of the patient's health status. Despite being a bidirectional construct, limited evidence is available to shed light on this issue in mental health units and even less so in the first days of admission. This study aimed to examine the association and differences between nurses' and patients' perspectives on the establishment of the therapeutic relationship in acute mental health units during the first days of hospitalization. A cross-sectional study was carried out in 12 Spanish mental health units. Data were collected from patients and nurses using the Working Alliance Inventory-Short (WAI-S) questionnaire. A total of 234 cases were analysed, including 234 patients and 58 nurses. The results showed a positive association between nurses' and patients' perspectives on the therapeutic relationship, but also revealed significant differences on each WAI-S dimension. Nurses assigned higher scores compared to patients on the perception of the quality of the therapeutic relationship. The dimensions with the greatest weight from the patients' perspective regarding the quality of the therapeutic relationship were the perception of greater agreement on goals and tasks among nurses. This study demonstrates the importance of establishing shared goals and tasks with nurses from the first days of hospitalization to improve the quality of the therapeutic relationship as perceived by patients. These findings underline the need to consider the different perspectives of both parties to promote a high-quality therapeutic relationship.


Asunto(s)
Enfermeras y Enfermeros , Enfermería Psiquiátrica , Humanos , Estudios Transversales , Salud Mental , Hospitalización , Encuestas y Cuestionarios
17.
Eur J Nutr ; 52(2): 737-47, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22645106

RESUMEN

AIMS OF THE STUDY: Wine polyphenols attenuate the development of atherosclerosis, which involves an inflammatory process. We studied the beneficial effect of de-alcoholised white and red wines (DWW and DRW, respectively) on the development of atheroma plaques and on the expression of biomarkers. METHODS: We administered control or de-alcoholised wine-rich diets to apoE-deficient mice for 12 or 20 weeks. We then used optical microscopy or immunofluorescence to examine atherosclerotic lesion development in the thoracic aorta and aortic root and assessed the presence of cytokines and adhesion molecules by qPCR and immunofluorescence in total aorta and aortic root, respectively. RESULTS: Atherosclerotic lesions in thoracic aorta were significantly decreased in mice supplemented with DWW (30 %) and DRW (62 %) for 20 weeks. In addition, the expressions of interferon-γ, interleukin-1ß, the monocyte chemoattractant protein-1 and CD68 were reduced by DRW. The adhesion molecule P-selectin, vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 were decreased by 52, 76 and 45 %, respectively, in mice fed DRW for 12 weeks, whereas DWW reduced these parameters in a minor extent. The NF-κB expression in total aorta was significantly decreased in the mice treated with de-alcoholised wines for 12 weeks. CONCLUSIONS: DRW is shown to be more effective than DWW on cytokines and adhesion molecule expression, in the early stages of the inflammatory events associated with atherosclerosis development, probably due to the high phenolic content of red wine. Downregulation of NF-κB expression may be involved in the mechanism by which de-alcoholised wines modulate atherosclerosis.


Asunto(s)
Apolipoproteínas E/deficiencia , Biomarcadores/sangre , Etanol/aislamiento & purificación , FN-kappa B/metabolismo , Placa Aterosclerótica/metabolismo , Vino/análisis , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/genética , Antígenos de Diferenciación Mielomonocítica/metabolismo , Aorta Torácica/efectos de los fármacos , Aorta Torácica/patología , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Regulación hacia Abajo , Técnica del Anticuerpo Fluorescente , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Interferón gamma/genética , Interferón gamma/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Selectina-P/genética , Selectina-P/metabolismo , Placa Aterosclerótica/patología , Polifenoles/farmacología , Molécula 1 de Adhesión Celular Vascular/genética , Molécula 1 de Adhesión Celular Vascular/metabolismo
18.
Dalton Trans ; 52(12): 3835-3845, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36866716

RESUMEN

The combination of molecular metallic fragments of contrasting Lewis character offers many possibilities for cooperative bond activation and for the disclosure of unusual reactivity. Here we provide a systematic investigation on the partnership of Lewis basic Rh(I) compounds of type [(η5-L)Rh(PR3)2] (η5-L = (C5Me5)- or (C9H7)-) with highly congested Lewis acidic Au(I) species. For the cyclopentadienyl Rh(I) compounds, we demonstrate the non-innocent role of the typically robust (C5Me5)- ligand through migration of a hydride to the Rh site and provide evidence for the direct implication of the gold fragment in this unusual bimetallic ligand activation event. This process competes with the formation of dinuclear Lewis adducts defined by a dative Rh → Au bond, with selectivity being under kinetic control and tunable by modifying the stereoelectronic and chelating properties of the phosphine ligands bound to the two metals. We provide a thorough computational study on the unusual Cp* non-innocent behavior and the divergent bimetallic pathways observed. The cooperative FLP-type reactivity of all bimetallic pairs has been investigated and computationally examined for the case of N-H bond activation in ammonia.

19.
ACS Catal ; 13(24): 16055-16066, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38344669

RESUMEN

The incorporation of boron functionalities into transition-metal catalysts has become a promising strategy to improve catalytic performance, although their synthesis typically entails the preparation of sophisticated bifunctional ligands. We report here the facile and direct postsynthetic functionalization of rhodium(I) compound [(η5-C9H7)Rh(PPh3)2] (1) by treatment with perfluorinated boranes. Borane addition to 1 results in an unusual C(sp2)-H hydride migration from the indenyl ligand to the metal with the concomitant formation of a C-B bond. In the case of Piers' borane [HB(C6F5)2], this is followed by a subsequent hydride migration that leads to an unprecedented 1,2-hydrogen shift reminiscent of Milstein's cooperative dearomatization pathways. Computational investigations provide a mechanistic picture for the successive hydride-migration steps, which enriches the non-innocent chemistry of widespread indenyl ligands. Moreover, we demonstrate that the addition of Piers' borane is highly beneficial for catalysis, increasing catalyst efficiency up to 3 orders of magnitude.

20.
Front Nutr ; 10: 1216445, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37789897

RESUMEN

Background: Metabolic syndrome (MS), a condition related to adiposity and oxidative stress, can develop in adolescence, a critical stage in life that impacts health in adulthood. However, there is scarce scientific research about the relationship between lifestyle factors, emotion management, and oxidative stress in this phase of life. Aim: To analyze whether nutritional parameters, lifestyle factors, emotion management, and MS in adolescents are associated with oxidative stress measured by the biomarker 8-isoprostane. Methods: A cross-sectional study was carried out in 132 adolescents (48.5% girls, aged 12 ± 0.48 years) and data were collected on nutritional parameters (anthropometric measurements, biochemical analyzes, and blood pressure), lifestyle factors (physical activity, sleep, and diet), and emotion management (self-esteem, emotional eating, and mood). 8-isoprostane was analyzed in spot urine samples. The study population was categorized in three groups (healthy, at-risk, and with MS) using the International Diabetes Federation definition of MS in adolescents. To capture more complex interactions, a multiple linear regression was used to analyze the association between 8-isoprostane and the aforementioned variables. Results: Urinary 8-isoprostane levels were significantly higher in the MS group compared to the healthy group (1,280 ± 543 pg./mg vs. 950 ± 416 pg./mg respectively). In addition, univariable analysis revealed positive significant associations between 8-isoprostane and body mass index, waist circumference, waist-to-height ratio, body fat percentage, blood lipid profile and glucose, emotional eating, and refined cereal intake. Conversely, a negative significant association was found between 8-isoprostane and sleep duration and fish intake. The multiple linear regression analysis revealed associations between 8-isoprostane and LDL-c (ß = 0.173 value of p = 0.049), emotional eating (low ß = 0.443, value of p = 0.036; high ß = 0.152, value of p = 0.470), refined cereal intake (ß =0.191, value of p = 0.024), and fish intake (ß = -0.187, value of p = 0.050). Conclusion: The MS group, LDL-c, emotional eating, and high refined cereals and low fish intakes were associated with higher levels of oxidative stress in an adolescent population.

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