Substituent-Induced Control of / Isomerism in Azine-NHC Fe(II) Complexes.

The stereoselective synthesis of geometrical iron(II) complexes bearing azine-NHC ligands is described. Facial and meridional selectivity is achieved as a function of the steric demand of the azine unit, with no remarkable influence of the carbene nature. More specifically, meridional complexes are obtained upon selecting bulky 5-mesityl-substituted pyridyl coordinating units.

Ultrafast Spectroscopy of Fe(II) Complexes Designed for Solar-Energy Conversion: Current Status and Open Questions.

One major challenge of future sustainable photochemistry is to replace precious and rare transition metals in applications such as energy conversion or electroluminescence by earth-abundant, cheap, and recyclable materials. This involves using coordination complexes of first row transition metals such as Cu, Cr, or Mn. In the case of iron, which is attractive due to its natural abundance, fundamental limitations imposed by the small ligand field splitting energy have recently been overcome.

Red-emitting neutral rhenium(i) complexes bearing a pyridyl pyridoannelated N-heterocyclic carbene.

Two novel rhenium(i) tricarbonyl complexes of general formula fac-[Re(N^C:)(CO)X] are herein presented, where N^C: is the pyridoannelated N-heterocyclic carbene (NHC) arising from 2-(2-pyridinyl)imidazo[1,5-a]pyridinium hexafluorophosphate proligand, namely [pyipy]PF, and X being Cl and Br. The synthetic pathway is a one-pot reaction that starts from the azolium salt as the NHC source and [Re(CO)X] to yield the desired charge-neutral fac-[Re(pyipy)(CO)X] complexes (1-2). Both complexes were thoroughly characterized by spectroscopic, electrochemical, theoretical investigation as well as X-ray diffraction analysis.

Prevalence of pre-diabetes and undiagnosed diabetes in the Mollerussa prospective observational cohort study in a semi-rural area of Catalonia.

Objectives: To assess the prevalence of undiagnosed diabetes and pre-diabetes in the healthy population in the Mollerussa cohort. As a secondary objective, to identify the variables associated with these conditions and to describe the changes in glycaemic status after 1 year of follow-up in subjects with pre-diabetes.

Design: Prospective observational cohort study.

Iron(ii) complexes with diazinyl-NHC ligands: impact of π-deficiency of the azine core on photophysical properties.

Ligand field enhancing N-heterocyclic carbene (NHC) ligands were recently shown to prevent photo-induced spin crossover in Fe(ii) complexes due to their intricate effects on the electronic excited state structure. Due to their pico- to nanosecond lifetimes, these complexes are now good candidates for photo-sensitizing applications. Herein we report the synthesis and photophysical characterization of a new family of homoleptic Fe(ii) complexes with C^N^C ligands involving diazines as the central N-heteroaromatic ligand.

Impact of the fac/ mer Isomerism on the Excited-State Dynamics of Pyridyl-carbene Fe(II) Complexes.

The control of photophysical properties of iron complexes and especially of their excited states decay is a great challenge in the search for sustainable alternatives to noble metals in photochemical applications. Herein we report the synthesis and investigations of the photophysics of mer and fac iron complexes bearing bidentate pyridyl-NHC ligands, coordinating the iron with three ligand-field-enhancing carbene bonds. Ultrafast transient absorption spectroscopy reveals two distinct excited state populations for both mer and fac forms, ascribed to the populations of the T and the T states, respectively, which decay to the ground state via parallel pathways.

Organoid single cell profiling identifies a transcriptional signature of glomerular disease.

Podocyte injury is central to many forms of kidney disease, but transcriptional signatures reflecting podocyte injury and compensation mechanisms are challenging to analyze in vivo. Human kidney organoids derived from pluripotent stem cells (PSCs), a potentially new model for disease and regeneration, present an opportunity to explore the transcriptional plasticity of podocytes. Here, transcriptional profiling of more than 12,000 single cells from human PSC-derived kidney organoid cultures was used to identify robust and reproducible cell lineage gene expression signatures shared with developing human kidneys based on trajectory analysis.

Regulation of Renal Differentiation by Trophic Factors.

Classically, trophic factors are considered as proteins which support neurons in their growth, survival, and differentiation. However, most neurotrophic factors also have important functions outside of the nervous system. Especially essential renal growth and differentiation regulators are glial cell line-derived neurotrophic factor (GDNF), bone morphogenetic proteins (BMPs), and fibroblast growth factors (FGFs).

genes direct elastin network formation during alveologenesis by regulating myofibroblast adhesion.

genes (, , ) are exclusively expressed in the lung mesenchyme during embryogenesis, and the most severe phenotypes result from constitutive loss of function of all three genes. Because triple null mutants exhibit perinatal lethality, the contribution of this paralogous group to postembryonic lung development is unknown. Intriguingly, expression of all three genes peaks during the first 2 weeks after birth, reaching levels far exceeding those measured at embryonic stages, and surviving single and compound mutants exhibit defects in the localization of alveolar myofibroblasts.

Dynamic MAPK/ERK Activity Sustains Nephron Progenitors through Niche Regulation and Primes Precursors for Differentiation.

The in vivo niche and basic cellular properties of nephron progenitors are poorly described. Here we studied the cellular organization and function of the MAPK/ERK pathway in nephron progenitors. Live-imaging of ERK activity by a Förster resonance energy transfer biosensor revealed a dynamic activation pattern in progenitors, whereas differentiating precursors exhibited sustained activity.

Single-cell analysis of progenitor cell dynamics and lineage specification in the human fetal kidney.

The mammalian kidney develops through reciprocal interactions between the ureteric bud and the metanephric mesenchyme to give rise to the entire collecting system and the nephrons. Most of our knowledge of the developmental regulators driving this process arises from the study of gene expression and functional genetics in mice and other animal models. In order to shed light on human kidney development, we have used single-cell transcriptomics to characterize gene expression in different cell populations, and to study individual cell dynamics and lineage trajectories during development.

Synthesis and Computational Study of a Pyridylcarbene Fe(II) Complex: Unexpected Effects of fac/ mer Isomerism in Metal-to-Ligand Triplet Potential Energy Surfaces.

The synthesis and the steady-state absorption spectrum of a new pyridine-imidazolylidene Fe(II) complex (Fe-NHC) are presented. A detailed mechanism of the triplet metal-to-ligand charge-transfer states decay is provided on the basis of minimum energy path (MEP) calculations used to connect the lowest-lying singlet, triplet, and quintet state minima. The competition between the different decay pathways involved in the photoresponse is assessed by analyzing the shapes of the obtained potential energy surfaces.

Radial WNT5A-Guided Post-mitotic Filopodial Pathfinding Is Critical for Midgut Tube Elongation.

The early midgut undergoes intensive elongation, but the underlying cellular and molecular mechanisms are unknown. The early midgut epithelium is pseudostratified, and its nuclei travel between apical and basal surfaces in concert with cell cycle. Using 3D confocal imaging and 2D live imaging, we profiled behaviors of individual dividing cells.

Recent advances in phosphorescent platinum complexes for organic light-emitting diodes.

Phosphorescent organometallic compounds based on heavy transition metal complexes (TMCs) are an appealing research topic of enormous current interest. Amongst all different fields in which they found valuable application, development of emitting materials based on TMCs have become crucial for electroluminescent devices such as phosphorescent organic light-emitting diodes (PhOLEDs) and light-emitting electrochemical cells (LEECs). This interest is driven by the fact that luminescent TMCs with long-lived excited state lifetimes are able to efficiently harvest both singlet and triplet electro-generated excitons, thus opening the possibility to achieve theoretically 100% internal quantum efficiency in such devices.

Haploinsufficiency for the Six2 gene increases nephron progenitor proliferation promoting branching and nephron number.

The regulation of final nephron number in the kidney is poorly understood. Cessation of nephron formation occurs when the self-renewing nephron progenitor population commits to differentiation. Transcription factors within this progenitor population, such as SIX2, are assumed to control expression of genes promoting self-renewal such that homozygous Six2 deletion results in premature commitment and an early halt to kidney development.

Controlling charge-transfer properties through a microwave-assisted mono- or bis-annulation of dialkynyl-N-(het)arylpyrroles.

A selective microwave-assisted mono- and bis-annulation of dialkynyl-N-(het)arylpyrrole derivatives is described. These polycyclic aromatic hydrocarbons (PAHs) have been photophysically and computationally characterized. The mono-annulated systems display interesting charge-transfer properties.

Metal-Containing Polymers as Light-Emitting and Light-Responsive Materials and Beyond.

Functional materials that respond to external stimuli are of major current interest. In particular, supramolecular systems that can interact with their surroundings, adapt to environmental changes and evolve with are even more fascinating, yet challenging. Combining the rich physico-chemical properties featured by metal centres with characteristics typical of classical organic polymers, metallopolymers or metallo-supramolecular polymers can be prepared, depending on their static versus dynamic structural features.

Ret and Etv4 Promote Directed Movements of Progenitor Cells during Renal Branching Morphogenesis.

Branching morphogenesis of the epithelial ureteric bud forms the renal collecting duct system and is critical for normal nephron number, while low nephron number is implicated in hypertension and renal disease. Ureteric bud growth and branching requires GDNF signaling from the surrounding mesenchyme to cells at the ureteric bud tips, via the Ret receptor tyrosine kinase and coreceptor Gfrα1; Ret signaling up-regulates transcription factors Etv4 and Etv5, which are also critical for branching. Despite extensive knowledge of the genetic control of these events, it is not understood, at the cellular level, how renal branching morphogenesis is achieved or how Ret signaling influences epithelial cell behaviors to promote this process.

Luminescent supramolecular soft nanostructures from amphiphilic dinuclear Re(I) complexes.

Luminescent metallo-surfactants based on highly emissive dinuclear Re(I) complexes have been synthesized combining the peculiar photophysical behaviour of this class of neutral hydrophobic complexes with new properties imparted by hydrophilic chains anchored on the coordinated chromophoric ligand. In solution, the resulting neutral amphiphiles tend to self-assembly in soft structures. The aggregation properties have been thoroughly investigated in dioxane-water mixtures, where all the complexes assembly in globular-like supramolecular architectures with well-defined size (hydrodynamic diameter = 200-400 nm).

Subclinical Carotid Atherosclerosis in Asymptomatic Subjects With Type 2 Diabetes Mellitus.

Background: Subjects with type 2 diabetes mellitus are considered to be at high risk for cardiovascular disease. The identification of carotid atherosclerosis is a validated surrogate marker of cardiovascular disease. Nurses are key professionals in the improvement and intensification of cardiovascular preventive strategies.

4-Aryl-3,5-bis(arylethynyl)aryl-4H-1,2,4-triazoles: multitasking skeleton as a self-assembling unit.

The synthesis of a series of 4-aryl-3,5-bis(arylethynyl)aryl-4H-1,2,4-triazoles derivatives is reported and the influence exerted by peripheral substitution on the morphology of the aggregates generated from these 1,2,4-triazoles is investigated by SEM imaging. The presence of paraffinic side chains results in long fibrillar supramolecular structures, but unsubstituted triazoles self-assemble into thinner ribbons and needle-like aggregates. The crystals obtained from methoxy-substituted triazoles have been utilised to elaborate a model that helps to justify aggregation of the investigated 1,2,4-triazoles, in which the operation of arrays of C-H⋅⋅⋅π non-covalent interactions plays a significant role.

Photofunctional nanomodulators for bioexcitation.

A single organism comprises diverse types of cells. To acquire a detailed understanding of the biological functions of each cell, comprehensive control and analysis of homeostatic processes at the single-cell level are required. In this study, we develop a new type of light-driven nanomodulator comprising dye-functionalized carbon nanohorns (CNHs) that generate heat and reactive oxygen species under biologically transparent near-infrared (NIR) laser irradiation.

Self-assembly of a neutral platinum(II) complex into highly emitting microcrystalline fibers through metallophilic interactions.

The solvent-assisted self-assembly of a blue-emitting neutral platinum(II) complex into micrometer-long and highly crystalline fibers has been achieved. The aggregates show highly efficient (quantum yield up to 74%) polarized yellow-orange light emission, as a consequence of their high degree of supramolecular order imparted by weak non-covalent intermolecular (metal···metal and π-π) interactions.

The number of fetal nephron progenitor cells limits ureteric branching and adult nephron endowment.

Nephrons, the functional units of the kidney, develop from progenitor cells (cap mesenchyme [CM]) surrounding the epithelial ureteric bud (UB) tips. Reciprocal signaling between UB and CM induces nephrogenesis and UB branching. Although low nephron number is implicated in hypertension and renal disease, the mechanisms that determine nephron number are obscure.

Fullerene-driven encapsulation of a luminescent Eu(III) complex in carbon nanotubes.

A novel CNT-based hybrid luminescent material was obtained via encapsulation of a C60-based Eu(III) complex into single-, double- and multi-walled carbon nanotubes (SWCNTs, DWCNTs and MWCNTs, respectively). Specifically, a luminescent negatively charged Eu(III) complex, electrostatically bonded to an imidazolium-functionalized fullerene cage, was transported inside CNTs by exploiting the affinity of fullerenes for the inner surface of these carbonaceous containers. The filling was performed under supercritical CO2 (scCO2) conditions to facilitate the entrapment of the ion-paired assembly.