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1.
Inj Prev ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38378256

RESUMEN

OBJECTIVES: This study examined trends in the frequencies and rates of deaths associated with unintentional injuries in sport and recreation in Québec, Canada, for the period January 2006-December 2019. METHODS: In this descriptive retrospective study, data were extracted from the database of the Bureau du coroner du Québec. Incidence rates were calculated using participation data from the Étude des blessures subies au cours de la pratique d'activités récréatives et sportives au Québec (ÉBARS) and Canadian census population data. Poisson regression was used to investigate changes in death rates over the 14-year period by estimating incidence rate ratios. RESULTS: There were 1937 unintentional injury deaths and the population-based death rate was 1.72 per 100 000 person-years. The participation-based rate was 1.40 per 100 000 participant-years, considering the 24 matching activities in both ÉBARS' editions. Using both population-based and participation-based denominators, separate analyses consistently showed declining death rates in non-motorised navigation and cycling. Deaths related to all-terrain vehicles, snowmobiles, swimming, cycling, motorised navigation and non-motorised navigation activities accounted for 80.2% of all deaths. Drowning was documented as a cause of death in 39.3% of all fatalities. Males represented 86.8% of all deaths, with males aged 18-24 years and 65 and over having the highest rates. CONCLUSION: The death rates of unintentional injury deaths associated with non-motorised navigation and cycling declined, from January 2006 to December 2019. The characteristics and mechanisms of drowning deaths and fatalities that occurred in activities associated with higher death frequencies and rates need to be further investigated.

2.
Chemistry ; 27(72): 18175-18187, 2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-34669988

RESUMEN

Cationic amidotitanocene complexes [Cp2 Ti(NPhAr)][B(C6 F5 )4 ] (Cp=η5 -C5 H5 ; Ar=phenyl (1 a), p-tolyl (1 b), p-anisyl (1 c)) were isolated. The bonding situation was studied by DFT (Density Functional Theory) using EDA-NOCV (Energy Decomposition Analysis with Natural Orbitals for Chemical Valence). The polar Ti-N bond in 1 a-c features an unusual inversion of σ and π bond strengths responsible for the balance between stability and reactivity in these coordinatively unsaturated species. In solution, 1 a-c undergo photolytic Ti-N cleavage to release Ti(III) species and aminyl radicals ⋅NPhAr. Reaction of 1 b with H3 BNHMe2 results in fast homolytic Ti-N cleavage to give [Cp2 Ti(H3 BNHMe2 )][B(C6 F5 )4 ] (3). 1 a-c are highly active precatalysts in olefin hydrogenation and silanes/amines cross-dehydrogenative coupling, whilst 3 efficiently catalyzes amine-borane dehydrogenation. The mechanism of olefin hydrogenation was studied by DFT and the cooperative H2 activation key step was disclosed using the Activation Strain Model (ASM).

3.
Mov Disord ; 35(7): 1224-1232, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32369665

RESUMEN

BACKGROUND: Hemizygous mutations in GRIA3 encoding the GluA3 subunit of the amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor are known to be associated with neurodevelopmental disorders, including intellectual disability, hypotonia, an autism spectrum disorder, sleep disturbances, and epilepsy in males. OBJECTIVE: To describe a new and consistent phenotype in 4 affected male patients associated with an undescribed deleterious variant in GRIA3. METHODS: We evaluated a large French family in which segregate a singular phenotype according to an apparent X-linked mode of inheritance. Molecular analyses using next generation sequencing and in vitro functional studies using 2-electrode voltage clamp recordings on Xenopus laevis oocytes and a ß-lactamase reporter assay in transfected human embryonic kidney (HEK293) cells were performed. RESULTS: In addition to mild intellectual disability and dysarthria, affected patients presented a tightly consistent early-onset movement disorder combining an exaggerated startle reflex with generalized chorea and multifocal myoclonus. The unreported GRIA3 missense variant c.2477G > A; p.(Gly826Asp) affecting the fourth transmembrane domain of the protein was identified in index patients and their unaffected mothers. Functional studies revealed that variant receptors show decreased current response evoked by agonist (ie, kainic acid and glutamate) and reduced expression on the cell surface in favor of pathogenicity by a loss-of-function mechanism. CONCLUSIONS: Taken together, our results suggest that apart from known GRIA3-related disorders, an undescribed mutation-specific singular movement disorder does exist. We thus advocate considering GRIA3 mutations in the differential diagnosis of hyperekplexia and generalized chorea with myoclonus. © 2020 International Parkinson and Movement Disorder Society.


Asunto(s)
Trastorno del Espectro Autista , Corea , Mioclonía , Células HEK293 , Humanos , Masculino , Mioclonía/genética , Reflejo de Sobresalto
4.
Chemistry ; 25(11): 2803-2815, 2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30506743

RESUMEN

Tame d0 phosphidotitanocene cations stabilized with a pendant tertiary phosphane arm are reported. These compounds were obtained by one-electron oxidation of d1 precursors with [Cp2 Fe][BPh4 ]. The electronic structure of these compounds was studied experimentally (EPR, UV/Vis, and NMR spectroscopy, X-ray diffraction analysis) and through DFT calculations. The theoretical analysis of the bonding situation by using the electron localization function (ELF) shows the presence of π-interactions between the phosphido ligand and Ti in the d0 complexes, whereas dπ-pπ repulsion prevents such interactions in the d1 complexes. In addition, CH-π interactions were observed in several complexes, both in solution and in the solid state, between the phosphido ligand and the phosphane arm. The d0 complexes were found to be light sensitive, and decompose through Ti-P bond homolysis to give TiIII species. A naked d0 phosphidotitanocene cation has been trapped by reaction with diphenylacetylene, yielding a Ti/P frustrated Lewis pair (FLP), which was found to be less reactive than a previously reported Zr analog.

5.
Eur J Appl Physiol ; 119(1): 191-200, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30350154

RESUMEN

PURPOSE: It has been shown that an inspiratory muscle warm-up (IMW) could enhance performance. IMW may also improve the near-infrared spectroscopy (NIRS)-derived tissue oxygen saturation index (TSI) during cycling. However, there exists contradictory data about the effect of this conditioning strategy on performance and muscle oxygenation. We examined the effect of IMW on speed skating performance and studied the underpinning physiological mechanisms related to muscle oxygenation. METHODS: In a crossover, randomized, single-blind study, eight elite speed skaters performed 3000 m on-ice time trials, preceded by either IMW (2 × 30 breaths, 40% maximal inspiratory pressure) or SHAM (2 × 30 breaths, 15% maximal inspiratory pressure). Changes in TSI, oxyhemoglobin-oxymyoglobin ([O2HbMb]), deoxyhemoglobin-deoxymyoglobin ([HHbMb]), total hemoglobin-myoglobin ([THbMb]) and HHbMbdiff ([O2HbMb]-[HHbMb]) in the right vastus lateralis muscle were monitored by NIRS. All variables were compared at different time points of the race simulation with repeated-measures analysis of variance. Differences between IMW and SHAM were also analyzed using Cohen's effect size (ES) ± 90% confidence limits, and magnitude-based inferences. RESULTS: Compared with SHAM, IMW had no clear impact on skating time (IMW 262.88 ± 17.62 s vs. SHAM 264.05 ± 21.12 s, effect size (ES) 0.05; 90% confidence limits, - 0.22, 0.32, p = 0.7366), TSI, HbMbdiff, [THbMb], [O2HbMb] and perceptual responses. CONCLUSIONS: IMW did not modify skating time during a 3000 m time trial in speed skaters, in the conditions of our study. The unchanged [THbMb] and TSI demonstrate that the mechanisms by which IMW could possibly exert an effect on performance were unaffected by this intervention.


Asunto(s)
Consumo de Oxígeno , Músculo Cuádriceps/fisiología , Músculos Respiratorios/fisiología , Ejercicio de Calentamiento/fisiología , Adulto , Rendimiento Atlético , Femenino , Humanos , Inhalación , Masculino , Reflejo , Patinación/fisiología
6.
Eur Radiol ; 28(5): 1977-1985, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29168007

RESUMEN

OBJECTIVES: To determine the degree of relationship between iodine concentrations derived from dual-energy CT (DECT) and perfusion CT parameters in patients with advanced HCC under treatment. METHODS: In this single-centre IRB approved study, 16 patients with advanced HCC treated with sorafenib or radioembolization who underwent concurrent dynamic perfusion CT and multiphase DECT using a single source, fast kV switching DECT scanner were included. Written informed consent was obtained for all patients. HCC late-arterial and portal iodine concentrations, blood flow (BF)-related and blood volume (BV)-related perfusion parameters maps were calculated. Mixed-effects models of the relationship between iodine concentrations and perfusion parameters were computed. An adjusted p value (Bonferroni method) < 0.05 was considered significant. RESULTS: Mean HCC late-arterial and portal iodine concentrations were 22.7±12.7 mg/mL and 18.7±8.3 mg/mL, respectively. Late-arterial iodine concentration was significantly related to BV (mixed-effects model F statistic (F)=28.52, p<0.0001), arterial BF (aBF, F=17.62, p<0.0001), hepatic perfusion index (F=28.24, p<0.0001), positive enhancement integral (PEI, F=66.75, p<0.0001) and mean slope of increase (F=32.96, p<0.0001), while portal-venous iodine concentration was mainly related to BV (F=29.68, p<0.0001) and PEI (F=66.75, p<0.0001). CONCLUSIONS: In advanced HCC lesions, DECT-derived late-arterial iodine concentration is strongly related to both aBF and BV, while portal iodine concentration mainly reflects BV, offering DECT the ability to evaluate both morphological and perfusion changes. KEY POINTS: • Late-arterial iodine concentration is highly related to arterial BF and BV. • Portal iodine concentration mainly reflects tumour blood volume. • Dual-energy CT offers significantly decreased radiation dose compared with perfusion CT.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/patología , Medios de Contraste/metabolismo , Femenino , Humanos , Yodo/metabolismo , Yopamidol/análogos & derivados , Yopamidol/metabolismo , Hígado/diagnóstico por imagen , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Imagen de Perfusión/métodos , Estudios Prospectivos , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados
7.
Bioorg Chem ; 80: 43-56, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29864687

RESUMEN

Here a new series of twenty-one organoselenides, of potential protective activity, were synthesized and tested for their intrinsic cytotoxicity, anti-apoptotic and antioxidant capacities in oligodendrocytes. Most of the organoselenides were able to decrease the ROS levels, revealing antioxidant properties. Compounds 5b and 7b showed a high glutathione peroxidase (GPx)-like activities, which were 1.5 folds more active than ebselen. Remarkably, compound 5a diminished the formation of the oligodendrocytes SubG1 peak in a concentration-dependent manner, indicating its anti-apoptotic properties. Furthermore, based on the SwissADME web interface, we performed an in-silico structure-activity relationship to explore the drug-likeness of these organoselenides, predicting the pharmacokinetic parameters for compounds of interest that could cross the blood-brain barrier. Collectively, we present new organoselenide compounds with cytoprotective and antioxidant properties that can be considered as promising drug candidates for myelin diseases.


Asunto(s)
Antioxidantes/química , Compuestos de Organoselenio/química , Sustancias Protectoras/química , Animales , Antioxidantes/síntesis química , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Diseño de Fármacos , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Ratones , Conformación Molecular , Oligodendroglía/citología , Oligodendroglía/efectos de los fármacos , Oligodendroglía/metabolismo , Compuestos de Organoselenio/farmacología , Sustancias Protectoras/síntesis química , Sustancias Protectoras/farmacología , Especies Reactivas de Oxígeno/metabolismo , Relación Estructura-Actividad
8.
Inorg Chem ; 55(21): 10907-10921, 2016 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-27748585

RESUMEN

A smart steric control of the metallocene backbone in bis- and poly(phosphino)ferrocene ligands favors intramolecular aurophilic interactions between [AuCl] fragments in polynuclear gold(I) complexes. We synthesized and characterized by multinuclear NMR and X-ray diffraction analysis mono-, di-, and polynuclear gold complexes of constrained ferrocenyl diphosphines, which bear either bulky tert-butyl groups or more flexible siloxane substituents at the cyclopentadienyl rings. The complexes meso-1,1'-bis(diphenylphosphino)-3,3'-di-tert-butylferrocene (4-m), rac-1,1'-bis[bis(5-methyl-2-furyl)phosphino]-3,3'-di-tert-butylferrocene (5-r), and rac-1,1'-bis(diphenylphosphino)-3,3'-bis[(tri-iso-propylsilyl)oxy]ferrocene (6-r) were used to form dinuclear gold complexes. Coordination of tert-butylated ferrocenyl phosphines generated aurophilic interactions in the corresponding dinuclear gold complexes, contrary to gold(I) complexes reported with 1,1'-bis(diphenylphosphino)ferrocene. The structurally related tetraphosphine 1,1',2,2'-tetrakis(diphenylphosphino)-4,4'-di-tert-butylferrocene (11) also gave access to mononuclear, dinuclear, and the original trinuclear gold chloride aurophilic complexes in which 14e- to 16e- gold centers coexist. In such complexes, nonbonded ("through-space") 31P-31P' nuclear spin couplings were evidenced by high-resolution NMR. In these interactions nuclear spin information is transferred between the lone-pair electron of an uncoordinated phosphorus P and a phosphorus P' that is involved in a σ covalent bond Au-P'. The dinuclear aurophilic complex displayed a concerted shuttling of its [ClAu···AuCl] fragment between the four phosphorus donors of the tetraphosphine ligand. Thus, an aurophilic Au···Au bond, which is assumed to be a weak energy interaction, can be conserved within a dynamic shuttling process at high temperature involving an intramolecular coordination-decoordination process of digold(I) at phosphorus atoms.

9.
Org Biomol Chem ; 14(19): 4511-8, 2016 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-27097718

RESUMEN

Bombesin (BBN) was covalently bound to graftable subphthalocyanine (SubPc) or to a cholesterol derivative, a component of a liposome that encapsulates non-graftable SubPc. The latter bioconjugation approach was suitable to address the stability of SubPc and was achieved by copper-free click-chemistry on the outer-face of the liposome. Liposomes were purified (FPLC) and then analyzed in size (outer diameter about 60 nm measured by DLS). In vitro binding studies allowed to determine the IC50 13.9 nM for one component of the liposome, cholesterol, conjugated to BBN. Hence, azido- (or alkynyl-) liposomes give fluorophores with no reactive functional group available on their backbone a second chance to be (indirectly) bioconjugated (with bombesin).


Asunto(s)
Bombesina/química , Indoles/química , Liposomas/química , Nanoestructuras/química , Alquinos/química , Azidas/química , Isoindoles
10.
Eur Radiol ; 25(8): 2362-70, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25749813

RESUMEN

OBJECTIVES: To evaluate both in vivo and in phantom studies, dose reduction, and image quality of body CT reconstructed with model-based iterative reconstruction (MBIR), performed during patient follow-ups for lymphoma. METHODS: This study included 40 patients (mean age 49 years) with lymphoma. All underwent reduced-dose CT during follow-up, reconstructed using MBIR or 50 % advanced statistical iterative reconstruction (ASIR). All had previously undergone a standard dose CT with filtered back projection (FBP) reconstruction. The volume CT dose index (CTDIvol), the density measures in liver, spleen, fat, air, and muscle, and the image quality (noise and signal to noise ratio, SNR) (ANOVA) observed using standard or reduced-dose CT were compared both in patients and a phantom study (Catphan 600) (Kruskal Wallis). RESULTS: The CTDIvol was decreased on reduced-dose body CT (4.06 mGy vs. 15.64 mGy p < 0.0001). SNR was higher in reduced-dose CT reconstructed with MBIR than in 50 % ASIR or than standard dose CT with FBP (patients, p ≤ 0.01; phantoms, p = 0.003). Low contrast detectability and spatial resolution in phantoms were not altered on MBIR-reconstructed CT (p ≥ 0.11). CONCLUSION: Reduced-dose CT with MBIR reconstruction can decrease radiation dose delivered to patients with lymphoma, while keeping an image quality similar to that obtained on standard-dose CT. KEY POINTS: • In lymphoma patients, CT dose reduction is a major concern. • Reduced-dose body CT provides a fourfold radiation dose reduction. • Optimized CT reconstruction techniques (MBIR) can maintain image quality.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Linfoma/diagnóstico por imagen , Fantasmas de Imagen , Dosis de Radiación , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Relación Señal-Ruido , Adulto Joven
11.
Inorg Chem ; 53(4): 2296-303, 2014 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-24499428

RESUMEN

A new series of gold(I) N-heterocyclic carbene (NHC) complexes based on xanthine ligands have been synthesized and characterized by mass spectrometry, NMR, and X-ray diffraction. The compounds have been tested for their antiproliferative properties in human cancer cells and nontumorigenic cells in vitro, as well as for their toxicity in healthy tissues ex vivo. The bis-carbene complex [Au(caffein-2-ylidene)2][BF4] (complex 4) appeared to be selective for human ovarian cancer cell lines and poorly toxic in healthy organs. To gain preliminary insights into their actual mechanism of action, two biologically relevant in cellulo targets were studied, namely, DNA (more precisely a higher-order DNA structure termed G-quadruplex DNA that plays key roles in oncogenetic regulation) and a pivotal enzyme of the DNA damage response (DDR) machinery (poly-(adenosine diphosphate (ADP)-ribose) polymerase 1 (PARP-1), strongly involved in the cancer resistance mechanism). Our results indicate that complex 4 acts as an efficient and selective G-quadruplex ligand while being a modest PARP-1 inhibitor (i.e., poor DDR impairing agent) and thus provide preliminary insights into the molecular mechanism that underlies its antiproliferative behavior.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Cafeína/química , Oro/química , Metano/análogos & derivados , Animales , Antineoplásicos/síntesis química , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Humanos , Concentración 50 Inhibidora , Ligandos , Metano/química , Estructura Molecular , Xantina/química
12.
Chembiochem ; 13(13): 1905-12, 2012 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-22930447

RESUMEN

The targeting of higher-order DNA structures has been thoroughly developed with G-quadruplex DNA but not with other structures like branched DNA (also known as DNA junctions). Because these alternative higher-order DNA architectures might be of high biological relevance, we implemented a high-throughput version of the FRET melting assay that enabled us to map the interactions of a candidate with four different DNA structures (duplex- and quadruplex DNA, three- and four-way junctions) in a rapid and reliable manner. We also introduce a novel index, the BONDS (branched and other noncanonical DNA selectivity) index, to conveniently quantify this differential affinity.


Asunto(s)
Cafeína/farmacología , ADN/química , Conformación de Ácido Nucleico/efectos de los fármacos , Compuestos Orgánicos de Oro/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Anticarcinógenos/química , Anticarcinógenos/farmacología , Secuencia de Bases , Cafeína/análogos & derivados , Transferencia Resonante de Energía de Fluorescencia , G-Cuádruplex/efectos de los fármacos , Modelos Moleculares , Compuestos Orgánicos de Oro/química , Bibliotecas de Moléculas Pequeñas/química , Termodinámica
13.
Org Biomol Chem ; 10(27): 5212-8, 2012 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-22689015

RESUMEN

Template-assembled synthetic G-quartet (TASQ) has been reported recently as a G-quadruplex ligand interacting with DNA according to an unprecedented, nature-inspired 'like likes like' approach, based on the association between two G-quartets, one being native (quadruplex) and the other one artificial (ligand). Herein, a novel TASQ-based ligand is designed, synthesized and its quadruplex-recognition properties are evaluated in vitro: PorphySQ (for porphyrin-templated synthetic G-quartet) displays enhanced quadruplex recognition properties as compared to the very first reported prototype (DOTASQ, for DOTA-templated synthetic G-quartet), since the porphyrin template insures a more stable intramolecular G-quartet fold due to self-stabilizing interactions that may take place intramolecularly between the porphyrin ring and the formed G-quartet.


Asunto(s)
G-Cuádruplex , Porfirinas/química , Enlace de Hidrógeno , Ligandos , Modelos Moleculares
14.
Inorg Chem ; 50(8): 3479-89, 2011 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-21405090

RESUMEN

A series of homobimetallic manganese cofacial porphyrin-corrole dyads were synthesized and investigated as to their electrochemistry, spectroelectrochemistry, and ligand binding properties in nonaqueous media. Four dyads were investigated, each of which contained a Mn(III) corrole linked in a face-to-face arrangement with a Mn(III) porphyrin. The main difference between compounds in the series is the type of spacer, 9,9-dimethylxanthene, anthracene, dibenzofuran, or diphenylether, which determines the distance and interaction between the metallomacrocycles. Each redox process of the porphyrin-corrole dyads was assigned on the basis of spectroscopic and electrochemical data and by comparison with reactions and properties of the monocorrole and the monoporphyrin which were examined under the same solution conditions. The Mn(III) porphyrin part of the dyad undergoes two major one-electron reductions in pyridine and benzonitrile, the first of which involves a Mn(III)/Mn(II) process and the second the addition of an electron to the conjugated π-ring system of the macrocycle. The Mn(III) corrole part of the dyads also exhibits two major redox processes, one involving Mn(III)/Mn(II) and the other Mn(III) to Mn(IV) under the same solution conditions. The potentials and reversibility of each electron transfer reaction were shown to depend upon the solvent, type of spacer separating the two macrocycles, and the presence or absence of axial ligation, the latter of which was investigated in detail for the case of acetate ion which was found to bind within the cavity of the dyad to both manganese centers, both before and after the stepwise electroreduction to the Mn(II) forms of the two macrocycles. An intramolecular chloride ion exchange between the porphyrin part of the dyads which contain Mn(III)Cl and the singly oxidized corrole in the dyad is observed after the Mn(III)/Mn(IV) reaction of the corrole, suggesting that chloride is coordinated inside the cavity in the neutral compound.


Asunto(s)
Manganeso/química , Metaloporfirinas/química , Porfirinas/química , Electroquímica , Metaloporfirinas/síntesis química , Estructura Molecular , Espectrofotometría Ultravioleta
15.
Inorg Chem ; 50(19): 9472-80, 2011 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-21875041

RESUMEN

An unprecedented series of titanocene-gold bi- and trimetallic complexes of the general formula [[(η(5)-C(5)H(5))(µ-η(5):κ(1)-C(5)H(4)(CH(2))(n)PPh(2))TiCl(2)](m)AuCl(x)](q+) (n = 0, 2, or 4; m = 1, x = 1, q = 0 or m = 2, x = 0, q = 1) have been prepared and characterized spectroscopically. The luminescence spectroscopy and photophysics of one of the compounds, [[(η(5)-C(5)H(5))(µ-η(5):κ(1)-C(5)H(4)PPh(2))TiCl(2)](2)Au]PF(6), have been investigated in 2MeTHF solution and in the solid state at 77 and 298 K. Evidence for interfragment interactions based on the comparison of electronic band positions and emission lifetimes, namely, triplet energy transfer (ET) from the Au- to the Ti-containing chromophores, is provided. The cytotoxicity of the complexes was evaluated on A2780 ovarian cancer cells and on their cisplatin-resistant cell line A2780cisR; the compounds showed activity in the low micromolar range that was markedly more active than the corresponding titanocene-phosphine precursors [(η(5)-C(5)H(5))(η(5)-C(5)H(4)(CH(2))(n)PPh(2))TiCl(2)], cisplatin, and, for some of them, the gold analogue [(PPh(3))AuCl]. In an attempt to draw preliminary structure-activity relationships, cell uptake measurements and interaction studies with plasmid DNA and the model protein ubiquitin (Ub) have been undertaken on some of the compounds.


Asunto(s)
Antineoplásicos/química , Oro/química , Compuestos Organometálicos/química , Titanio/química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Oro/farmacología , Humanos , Luminiscencia , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/farmacología , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta , Relación Estructura-Actividad , Titanio/farmacología
16.
Inorg Chem ; 49(19): 8929-40, 2010 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-20822173

RESUMEN

The synthesis and characterization of a new type of bisporphyrin system is reported where the two macrocycles are linked in a cofacial arrangement by a substituted carbazole bridge. The three nitrogen atoms of the carbazole bridge in the compounds may complex a metal ion and thus provide a new parameter for varying the physical properties and flexibility of the dyad after formation of a three-metal system. In the present study, four bis-metalloporphyrin complexes were synthesized and examined by electrochemistry and thin-layer spectroelectrochemistry in CH(2)Cl(2) and PhCN. Two of the examined compounds contain Cu(II) or Zn(II) porphyrins and a carbazole linker with a bound Cu(II) ion, giving a three metal system, while the other two examined compounds contained the same porphyrins but with a carbazole bridge which lacks the Cu(II) component. Since carbazoles and Cu(II) ions are both electroactive, redox properties of several unlinked carbazoles with and without bound Cu(II) ions were also examined as to their electrochemical behavior under the same solution conditions as the dyads to better understand the redox reactions which may occur at the carbazole group linking the two porphyrin macrocycles. Several mononuclear porphyrins with structures related to macrocycles in the dyads were also investigated.


Asunto(s)
Cobre/química , Metaloporfirinas/síntesis química , Porfirinas/química , Zinc/química , Metaloporfirinas/química , Estructura Molecular , Estereoisomerismo
17.
Stud Health Technol Inform ; 155: 153-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20543323

RESUMEN

New technologies for drug identification, traceability and mobile platforms make it possible to personalise the services provided to consumers of medicine. This paper presents the Health-Identity platform, a mobile application which gives consumers the assurance that the drug they have in their hands is a genuine product and can be consumed without risk according to their stored patient profile (allergies, health state, current medication, etc.).


Asunto(s)
Computadoras de Mano , Información de Salud al Consumidor , Servicios de Información sobre Medicamentos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Aplicaciones de la Informática Médica , Humanos
18.
Chem Sci ; 12(1): 253-269, 2020 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34163594

RESUMEN

The synthesis and characterization of a range of bis(iminophosphoranyl)phosphide (BIPP) group 4 and coinage metals complexes is reported. BIPP ligands bind group 4 metals in a pseudo fac-fashion, and the central phosphorus atom enables the formation of d0-d10 heterobimetallic complexes. Various DFT computational tools (including AIM, ELF and NCI) show that the phosphorus-metal interaction is either electrostatic (Ti) or dative (Au, Cu). A bridged homobimetallic Cu-Cu complex was also prepared and its spectroscopic properties were investigated. The theoretical analysis of the P-P bond in BIPP complexes reveals that (i) BIPP are closely related to ambiphilic triphosphenium (TP) cations; (ii) the P-P bonds are normal covalent (i.e. not dative) in both BIPP and TP.

19.
Eur J Radiol ; 133: 109387, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33166833

RESUMEN

OBJECTIVES: To evaluate the reliability of attenuation values of the liver parenchyma and focal liver lesions on virtual unenhanced images from arterial (VUEart) and portal venous phases (VUEport) compared to native unenhanced (NU) attenuation values in patients referred for assessment of malignant liver lesions. METHODS: Seventy-three patients with confirmed primary or metastatic liver tumors who underwent a multiphase contrast-enhanced rapid-switching kVp dual-energy CT (rsDECT) were included in this IRB-approved retrospective study. Both qualitative and quantitative analyses - including the lesion-to-liver contrast-to-noise ratio (LL-CNR) - were performed and compared between NU and both VUEart and VUEport images. RESULTS: The mean liver attenuation values were significantly lower in VUEart images (56.7 ±â€¯6.7 HU) than in NU images (59.6 ±â€¯7.5 HU, p = 0.008), and were comparable between VUEart and VUEport images (57.9 ±â€¯6 UH, p = 0.38) and between VUEport and NU images (p = 0.051). The mean liver lesions attenuation values were comparable between NU, VUEart and VUEport images (p = 0.60). Strong and significant correlations values were found both in liver lesions and tumor-free parenchyma (r = 0.82-0.91, p < 0.01). The mean LL-CNR was significantly higher in VUEart and VUEport images than in NU images (1.7 ±â€¯1 and 1.6 ±â€¯1.1 vs 0.9 ±â€¯0.6; p < 0.001), but was comparable between VUEart and VUEport images (p > 0.9). Lesion conspicuity was significantly higher in VUEport images than in NU images (p < 0.001). CONCLUSION: VUEport images derived from 3rd generation rsDECT could confidently replace NU images in patients undergoing assessment for malignant liver lesions. These images provide comparable attenuation values in both liver lesions and liver parenchyma while reducing the radiation dose and scanning time.


Asunto(s)
Neoplasias Hepáticas , Imagen Radiográfica por Emisión de Doble Fotón , Medios de Contraste , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
20.
Dalton Trans ; 49(21): 6989-7004, 2020 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-32426779

RESUMEN

We report the synthesis of a series of Zr and Ti complexes bearing phosphasalen which differs from salen by the incorporation of two P atoms in the ligand backbone. The reaction of phosphasalen proligands (1a-1c)H2 with Zr(CH2Ph)4 led to different products depending on the nature of the N,N-linker in the ligand. In the case of ethylene-linked phosphasalen, octahedral Zr complex 2a formed as a single stereoisomer in trans geometry. With the phenylene linker, it was shown by dynamic NMR spectroscopy that complex 2b exists as a mixture of trans and cis-ß isomers in solution, both enantiomers (Δ and Λ) of the cis-ß isomer being in fast equilibrium with respect to the NMR time-scale. The use of a propylene-linked phosphasalen proligand 1cH2 led to a mixture of complexes among which a binuclear Zr complex 2c bridged only by one phosphasalen ligand could be isolated and characterized. Addition of 2 equiv. of iPrOH to 2a and 2b afforded diisoproxy Zr complexes 3a and 3b as a mixture of trans and cis-ß isomers, the latter undergoing fast Δ/Λ isomerization in solution. Addition of B(C6F5)3 to 2a and 2b gave cationic monobenzyl Zr complexes 4a and 4b which have been further converted into cationic alkoxy Zr complexes 5a-b and 6a-b by alcoholysis with iPrOH and (S)-methyl-lactate, respectively. The reaction of the phosphasalen proligands with Ti(NMe2)4 proceeded diastereoselectively giving rise to Ti complexes 7a-c in octahedral geometry with cis-ß wrapping of the ligand. The complexes have been tested for the ROP of rac-lactide. The neutral phosphasalen Ti and Zr complexes showed only poor activity probably due to the encumbered and electron donating nature of the phosphasalen ligand. In contrast, the cationic Zr alkoxides 5a, 6a and 6b are effective initiators for the controlled and hetero-selective ROP of rac-lactide.

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