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The association of the [Ln(hfac)3(H2O)2] metallic building blocks with the new ligand [1,1’-binaphthalene]-8,8’-diylbis(diphenylphosphine oxide) (L) led to the formation of three mononuclear complexes of formula [Ln(hfac)3(L)] (LnIII = Eu (1), Dy (2) and Yb (3)). The mononuclear character of the compounds is due to the bidentate coordination mode adopted by L to link the metal. L allows the observation of the characteristic visible 5D0  7FJ (J = 0-4) EuIII- and near infrared 2F5/2  2F7/2 YbIII- emissions while 2 is only weakly emissive due to the mismatch between the energy positions of the triplet excited state of the ligand and DyIII emissive state. The magnetic data reveal a field-induced Single-Molecule Magnet (SMM) behavior for 2 and 3 with an efficient suppression of the Quantum Tunneling of the Magnetization (QTM). The slow magnetic relaxation occurs through a Raman process while the Orbach contribution is discarded as confirmed by the correlation with the MJ states energy splitting provided by the luminescence spectrum of 3, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Photodynamic therapy (PDT) ideally relies on the administration, selective accumulation and photoactivation of a photosensitizer (PS) into diseased tissues. In this context, we report a new heavy-atom-free fluorescent G-quadruplex (G4) DNA-binding PS, named DBI. We reveal by fluorescence microscopy that DBI preferentially localizes in intraluminal vesicles (ILVs), precursors of exosomes, which are key components of cancer cell proliferation. Moreover, purified exosomal DNA was recognized by a G4-specific antibody, thus highlighting the presence of such G4-forming sequences in the vesicles. Despite the absence of fluorescence signal from DBI in nuclei, light-irradiated DBI-treated cells generated reactive oxygen species (ROS), triggering a 3-fold increase of nuclear G4 foci, slowing fork progression and elevated levels of both DNA base damage, 8-oxoguanine, and double-stranded DNA breaks. Consequently, DBI was found to exert significant phototoxic effects (at nanomolar scale) toward cancer cell lines and tumor organoids. Furthermore, in vivo testing reveals that photoactivation of DBI induces not only G4 formation and DNA damage but also apoptosis in zebrafish, specifically in the area where DBI had accumulated. Collectively, this approach shows significant promise for image-guided PDT.

The hydrolysis of the collagen matrix by metalloproteinases (MMPs) is one of the paradigms that currently arouses most interest due to its close relationship with a decrease in bond strength (BS) and consequent restoration failure. Chlorhexidine 2% has demonstrated its ability to inhibit MMPs’ activity in the permanent dentition, improving the duration of resin–dentine, but there are few studies on deciduous dentition and its possible repercussions. Aim: To determine the influence of 2% chlorhexidine digluconate (CHX) as a dentine pretreatment on the BS of three adhesive systems on primary molars. Methods: 128 primary extracted molars were assigned to eight groups at random. BS in vitro was recorded by micropush-out test, and analyzed by two-way ANOVA. Results: BS values oscillated from 15.01 MPa to 20.41 MPa. There was no statistically relevant variation between the BS total mean of those adhesive groups that had received CHX pretreatment versus those that did not. Adper Prompt L-Pop was the self-etching adhesive with the best BS. Adper Scotchbond 1XT was the total-etch adhesive with the best BS values. Conclusions: Application of 2% chlorhexidine for 60 s as dentine pretreatment did not affect the immediate BS of several adhesive systems used in primary dentition., Depto. de Odontología Conservadora y Prótesis, Fac. de Odontología, TRUE, pub

Los procedimientos restauradores realizados en la dentición primaria constituyen el principal acto operatorio en las clínicas dentales infantiles. Los nuevos adhesivos, los cuales, disminuyen las etapas del proceso adhesivo, se están convirtiendo en la estrategia de elección para todos los profesionales implicados en la odontología restauradora pediátrica. Pese a los importantes progresos de la tecnología adhesiva, la duración en términos clínicos de las resinas compuestas sigue siendo muy corta en la actualidad. Las estrategias destinadas a potenciar la duración de las uniones resina-dentina, y así tratar de evitar los fracasos de las restauraciones, se basan en la habilidad de impedir la acción de las enzimas endógenas de la dentina. La dentina contiene enzimas colagenolíticas, metaloproteinasas de la matriz (MMPs) y catepsinas de cisteína. Las MMPs constituyen un grupo de enzimas con dependencia del zinc y del calcio que regulan los mecanismos fisiológicos y patológicos de los tejidos basados en el colágeno. En varios estudios se ha señalado que las metaloproteinasas endógenas, tales como las colagenasas (MMP-8) y las gelatinasas (MMP-2 y -9), intervienen en la evolución de las lesiones de caries y en la alteración de la capa híbrida creada en el proceso de adhesión. La clorhexidina (CHX) es un antiséptico y antimicrobiano de amplio espectro que se adhiere a los aminoácidos de la dentina y sigue frenando la actividad bacteriana por varias horas. Además, es un potente inhibidor de las MMPs. Así, una concentración del 2% de digluconato de clorhexidina, utilizada como pretratamiento de la dentina, puede inhibir el 99% de la capacidad colagenolítica de las metaloproteinasas. Sin embargo, el pretratamiento con clorhexidina puede convertirse en un problema si interfiere con los procedimientos de adhesión a la dentina. Aunque muchos estudios han descrito la influencia de la clorhexidina en la fuerza de adhesión a los dientes permanentes, su efecto en la dentición primar, Restorative procedures performed in the primary dentition constitute the main operative act in children’s dental clinics. New adhesives, which shorten the adhesive process steps, are becoming the strategy of choice for all professionals involved in paediatric restorative dentistry. Despite significant advances in adhesive technology, the clinical longevity of composite resins remains very short today. Strategies aimed at enhancing the durability of resin-dentine bonds, and thus trying to avoid restoration failures, are based on the ability to impede the action of endogenous enzymes in dentine. Dentine contains collagenolytic enzymes, matrix metalloproteinases (MMPs) and cysteine cathepsins. MMPs constitute a group of zinc- and calcium-dependent enzymes that regulate physiological and pathological mechanisms of collagen-based tissues. Endogenous metalloproteinases, such as collagenases (MMP-8) and gelatinases (MMP-2 and -9), have been reported in several studies to be involved in the evolution of caries lesions and in the alteration of the hybrid layer created in the adhesion process. Chlorhexidine (CHX) is a broad-spectrum antiseptic and antimicrobial that binds to amino acids in dentin and continues to slow bacterial activity for several hours. In addition, it is a potent inhibitor of MMPs. Thus, a 2% concentration of chlorhexidine digluconate, used as a dentin pretreatment, can inhibit 99% of the collagenolytic capacity of metalloproteinases. However, chlorhexidine pretreatment can become a problem if it interferes with dentin bonding procedures. Although many studies have described the influence of chlorhexidine on bond strength to permanent teeth, its effect in primary dentition is still unclear...

Mammalian digit tip regeneration is linked to the presence of nail tissue, but a nail-explicit model is missing. Here, we report that nail-less double-ventral digits of dLARM1/2 mutants that lack limb-specific Lmx1b enhancers fail to regenerate. To separate the nail's effect from the lack of dorsoventral (DV) polarity, we also interrogate double-dorsal double-nail digits and show that they regenerate. Thus, DV polarity is not a prerequisite for regeneration, and the nail requirement is supported. Transcriptomic comparison between wild-type and non-regenerative dLARM1/2 mutant blastemas reveals differential upregulation of vascularization and connective tissue functional signatures in wild type versus upregulation of inflammation in the mutant. These results, together with the finding of Lmx1b expression in the postnatal dorsal dermis underneath the nail and uniformly in the regenerative blastema, open the possibility of additional Lmx1b roles in digit tip regeneration, in addition to the indirect effect of mediating the formation of the nail.

Synthetic procedures, experimental details of physical measurements, IR spectra and MS diagrams of all complexes, details, tables and figures of SCXRD molecular structures, and detailed emission spectra and analysis

The ligand H3 L (6-[3-oxo-3-(2-hydroxyphenyl)propionyl]pyridine-2-carboxylic acid), which exhibits two different coordination pockets, has been exploited to engender and study energy transfer (ET) in two dinuclear [LnIII LnIII '] analogues of interest, [EuYb] and [NdYb]. Their structural and physical properties have been compared with newly synthesised analogues featuring no possible ET ([EuLu], [NdLu], and [GdYb]) and with the corresponding homometallic [EuEu] and [NdNd] analogues, which have been previously reported. Photophysical data suggest that ET between EuIII and YbIII does not occur to a significant extent, whereas emission from YbIII originates from sensitisation of the ligand. In contrast, energy migration seems to be occurring between the two NdIII centres in [NdNd], as well as in [NdYb], in which YbIII luminescence is thus, in part, sensitised by ET from Nd. This study shows the versatility of this molecular platform to further the investigation of lanthanide-to-lanthanide ET phenomena in defined molecular systems.

Aza-boron-dipyrromethenes (Aza-BODIPYs) are an increasingly studied class of fluorophores. They can be seen as an azadipyrromethene (“aza-DIPY”) ligand rigidified by a metalloid, a boron atom. Based on this idea, a series of complexes of group 13 metals (aluminum and gallium) have been synthesized and characterized. The impact of the metal and of the nature of the substituents of aza-DIPY core were investigated. The photophysical and electrochemical properties were determined, and an X-ray structure of an azaGaDIPY was obtained. These data reveal that azaGaDIPY and azaAlDIPY exhibit significant red-shifted fluorescence compared to their analogue aza-BODIPY. Their emission can go up to 800 nm for the maximum emission length and up to NIR-II for the emission tail. This, associated with their electrochemical stability (no metal release whether oxidized or reduced) makes them a promising class of fluorophores for optical medical imaging. Moreover, X-ray structure and molecular modeling studies have shown that this redshift seems to be more due to the geometry around the boron/metal than to the nature of the metal., Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

The dorso-ventral (DV) limb asymmetry is crucial for its function; however, little is known about how it is accomplished during morphogenesis. Lmx1b is the key regulator of DV patterning during limb development as it is both necessary and sufficient to specify dorsal fates, but its regulation remains poorly known. We recently demonstrated a complex autoregulatory mode of transcriptional Lmx1b regulation mediated by two limb-specific enhancers, LARM1 and LARM2. The deletion of both enhancers (dLARM1/2) reproduces the Lmx1b-null phenotype in the limb, while the removal of each enhancer produced a double ventral phenotype restricted to the posterior (dLARM1) or anterior (dLARM2) half of the limb. To investigate the regulatory logic of the Lmx1b locus in detail, we dissected the LARM1 element into its enhancer and silencer sequences and explored the functional contribution of the two Lmx1b-associated lncRNAs. The results confirm the presence of a functional repressor contained in LARM1 and underscore the positional specificity of the LARM sequences. The data suggests that Lmx1b transcription uses different regulatory elements in different positions probably reflecting the integration of the local transcriptional environment. Indeed, published ChIP-seq data showed the Gli3 and Hox13 are significantly enriched in the LARM sequences exposing their interaction with major limb regulators. Finally, considering that the double-ventral limbs of dLARM1/2 mutants fail to support locomotion, even to lift the body weight, we hypothesized that the elaboration of the DV asymmetry by modification of Lmx1b regulation, or its functional targets, had to accompany the fin to limb transition. We have identified orthologs of the LARMs in fishes and all of them show activity in the pectoral fin in zebrafish reporter essays, revealing the deep roots of Lmx1b regulation.

© 2019 The Royal Society of Chemistry. Herein we report a nanorod couple heterostructure made of dual semiconductors, in which two parallelly aligned ZnSe nanorods are connected by the growth of ZnS on both end and side facets, producing hetero-ZnS (short arms)-ZnSe (long arms)/ZnS shell nanorod couples. As evidenced by electronic structure studies, both experimental and theoretical, such core/shell nanorod couple heterostructures can act as a platform to precisely tailor the quantum confinement of charge carriers between the constituting components within a single nano-object, generating blue fluorescence after the overgrowth of an alloyed ZnCdS layer on the heterostructures. We foresee the mechanistic insights gained and electronic structures revealed in this work would shed light on the rational design of more complex heterostructures with novel functionalities.

La adquisición de las competencias de diagnóstico de la patología bucodental de los pacientes pediátricos resulta fundamental para los futuros egresados del Grado en Odontología. Así como de aquellas competencias profesionalizantes relativas a la realización del plan de tratamiento y la elaboración del cronograma, ordenando cada una de las citas de acuerdo a las necesidades de tratamiento detectadas. Este proyecto surge por la necesidad de generar nuevas metodologías docentes que favorezcan el aprendizaje autodirigido. Los objetivos principales son: Fomentar la adquisición de competencias horizontales y específicas del alumno, incrementando sus conocimientos sobre el diagnóstico de la patología bucodental del paciente infantil, la elaboración del plan de tratamiento y el cronograma. Favorecer el aprendizaje híbrido presencial y a distancia mediante el desarrollo de herramientas online, accesibles para el alumno en cualquier lugar y momento. Estimular el aprendizaje autónomo del alumno, permitiendo la adquisición de competencias teórico-prácticas en cuanto al diagnóstico y la planificación del tratamiento odontopediátrico. Mejorar el proceso de autoevaluación del alumno, como feedback en su aprendizaje. Creando una herramienta online para la presentación y el análisis de problemáticas concretas respecto a los objetivos planteados.

The ligand HL (6-[3-oxo-3-(2-hydroxyphenyl)propionyl]pyridine-2-carboxylic acid), which exhibits two different coordination pockets, has been exploited to engender and study energy transfer (ET) in two dinuclear [LnLn′] analogues of interest, [EuYb] and [NdYb]. Their structural and physical properties have been compared with newly synthesised analogues featuring no possible ET ([EuLu], [NdLu], and [GdYb]) and with the corresponding homometallic [EuEu] and [NdNd] analogues, which have been previously reported. Photophysical data suggest that ET between Eu and Yb does not occur to a significant extent, whereas emission from Yb originates from sensitisation of the ligand. In contrast, energy migration seems to be occurring between the two Nd centres in [NdNd], as well as in [NdYb], in which Yb luminescence is thus, in part, sensitised by ET from Nd. This study shows the versatility of this molecular platform to further the investigation of lanthanide-to-lanthanide ET phenomena in defined molecular systems.

© 2019 The Royal Society of Chemistry. Herein we report a nanorod couple heterostructure made of dual semiconductors, in which two parallelly aligned ZnSe nanorods are connected by the growth of ZnS on both end and side facets, producing hetero-ZnS (short arms)-ZnSe (long arms)/ZnS shell nanorod couples. As evidenced by electronic structure studies, both experimental and theoretical, such core/shell nanorod couple heterostructures can act as a platform to precisely tailor the quantum confinement of charge carriers between the constituting components within a single nano-object, generating blue fluorescence after the overgrowth of an alloyed ZnCdS layer on the heterostructures. We foresee the mechanistic insights gained and electronic structures revealed in this work would shed light on the rational design of more complex heterostructures with novel functionalities.