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Split nail (SN) is a rare type of nail fragility syndrome, characterized by a longitudinal fissure involving the entire thickness of the nail plate. Longitudinal nail splitting may be caused by direct injury to the nail plate or matrix insult. Few articles have been published on the topic, most were related to the traumatic aetiology. Some case reports mention tumours and inflammatory disorders as other causes.The aim of this retrospective study was to analyse the clinical and histopathological features of 56 SN collected at the nail consultation of the dermatology department at Saint Pierre University Hospital in Brussels, between 1997 and 2019.Fifty-six patients were included (34 women and 22 men) with median age of 44.2 years. The fingernails were 3.2 times more frequently affected than toenails, especially the thumb. The most frequent aetiologies were tumours (45.6%), inflammatory diseases (26.3%) and traumas (19.3%). Congenital (5.3%) and systemic disorders (3.5%) were rarer causes. Histopathological slide review confirmed that alteration of the nail matrix integrity causes split nail, resulting either from matrix stretching by an underlying tumour or from impairment of the keratinization process by inflammatory diseases, melanocytic tumours and Bowen's disease.This study is the largest case series of longitudinal nail splitting to date. It is the first to gather nail disorders causing SN with their clinical pathological correlation. The most common causes are traumatisms, tumours and inflammatory disorders. Congenital and systemic disorders are rarer. Tumours are responsible for half of the cases from which one third are malignant, mainly melanoma. When facing a monodactylic SN, benign as well as malignant tumours should be ruled out before concluding to traumatic aetiology.

In 1987, Pedersen, Cram, and Lehn were awarded the Nobel Prize in Chemistry to honor their achievements in, among other things, the selective recognition of alkali metal ions by synthetic hosts. Almost three decades later, the 2016 Nobel Prize went to Stoddart, Sauvage, and Feringa for the development of artificial molecular machines, in which interlocked molecules play a significant role. Surprisingly, although many rotaxane- and catenane-based molecular machines have been constructed using various templating approaches, alkali metal ions, which are good templates for crown ether synthesis, have only rarely been applied as templates for the assembly of these interlocked molecules. This paucity of examples is probably due to the less well defined coordination numbers and geometries in the complexation of alkali metal ions to common oxygen-containing ligands, resulting in much weaker metal-ligand interactions and less predictable structures for their complexes compared with those formed between transition metal ions and common pyridine-containing ligands. Nevertheless, the ease of removing alkali metal ions from interlocked compounds and their much lower toxicity compared with that of transition metal ions are attractive features that have inspired their use as templates in the synthesis of interlocked molecules. About a decade ago, we began investigating the feasibility of using alkali metal ions to template the formation of catenanes and rotaxanes, with the hope of developing facile, broadly applicable, green, and efficient methods for their construction. We noticed that the interactions between oxygen-containing ligands and alkali metal ions can be strengthened by minimizing the effects of competing interactions from solvent molecules and counteranions. Thus, to increase the solubility of the metal ion salts in less polar solvents (e.g., CH

Calixarenes are widely used as molecular platforms in supramolecular chemistry. Their efficient modification is key for appending functional moieties such as binding, sensing, chiral, or hydrophilic subunits. Due to the presence of multiple identical functional groups, selective functionalization of such macrocyclic compounds is highly challenging. Indeed, the control of the chemo-, regio-, stereo- as well as iteroselectivity is required. This review describes rational methods leading to a high degree of regio- and/or iteroselectivity and classifies them into specific strategies. Many of these strategies are conceptually very general and hopefully will be a source of inspiration for developing selective methods for other macrocyclic platforms.

A young woman presented with initial epileptic seizures and multiple ‘mass-like’ lesions seen on computed tomography and magnetic resonance imaging. Given this presentation and her past medical history, a cerebral biopsy was performed to rule out malignancy, but showed a necrotizing cerebral vasculitis. We describe this case to reinforce the view that primary central nervous system vasculitis (PCNSV) should be considered in the differential diagnosis of a cerebral mass, even if uncommon. LEARNING POINTS PCNSV may cause a variety of clinical manifestations including seizures. PCNSV lesions can mimic a cerebral mass. Brain biopsy remains the gold standard for the diagnosis of PCNSV, especially to rule out a cancer diagnosis.

International audience; A water-soluble calix[6]arene-based azacryptand was synthesized. The corresponding tren [tris(2-aminoethyl)amine] cap grafted at the small rim coordinates strongly a copper(II) ion over a wide range of pH. The host–guest properties of the complex were explored by EPR spectroscopy. Due to second coordination sphere effects and the hydrophobic effect ascribed to the calixarene cavity, this funnel complex selectively binds neutral molecules (alcohols, nitriles, amines) versus anions in water near physiological pH. Among the coordinating guests, hydrophobic primary amines are preferentially recognized thanks to the combined effect of the better metal–ligand interaction and hydrogen bonding to the oxygen atoms present at the small rim. Hence, this Cu(II) calix[6]arene-based funnel complex behaves as a sensitive and selective EPR probe for primary amines, including biologically important molecules such as tyramine and tryptamine, in water, over a large pH window.

[2]Rotaxanes displaying one-off photo-triggerable gelation properties have been synthesized through the "clipping" of photo-degradable macrocycles around the amide or urea functionalities of organo- and hydrogelators. Irradiation with UV-light cleaved the photo-labile macrocyclic components from the [2]rotaxanes, resulting in the free gelators being released into solution and, thereafter, forming gels. When the rate of gelation was sufficiently rapid, selective gelation of specific regions of the solution-and, indeed, photo-patterning of the solution-was possible.

In recent years knowledge about Alzheimer's disease (AD) presented a major change since the availability of new diagnostic criteria incorporating biomarkers within the known cl inical criteria. Such criteria were elaborated by NIA-AA (National Institute on Aging - Alzheimer's Association) for clinical use and IWG (International Working Group) for research purpose. The aim of this study is to investigate the use of complementary examinations included in the NIA-AA and IWG criteria in a memory clinic characterized by a heterogenous population of patients.We retrospectively reviewed patient's characteristics of cases consulting between 01/01/2010 and 31/12/2013 based on the implementation of three additional tests: neuropsychological testing, measurement of cerebrospinal fluid (CSF) biomarkers and brain MRI. Patients were compared according to their origins.919 patients' medical records were included in the study, 20 % of which were from immigrant background. Non-European Union migrants underwent less neuropsychological testing and more lumbar punctures in comparison with the local population.CSF biomarkers allow defining an objective diagnostic component of AD by suppressing the variability due to language, culture, education and the clinical presentation of the disease. Despite the known use in the research domain but not yet validated for clinical use, the IWG criteria are applied in heterogeneous populations with a high percentage of migrants, especially when the results of the neuropsychological testing are poorly contributive. We expect recommendations for clinical use of the CSF biomarkers or better cognitive assessment methods for these populations in the future.A ce jour, notre vision de la maladie d’Alzheimer (MA) connaît un changement majeur depuis l ’apparition de nouveaux critères diagnostiques incorporant des biomarqueurs aux critères cliniques connus. La NIA-AA (National Institute on Aging - Alzheimer’s Association) en a élaboré pour la pratique courante et l’IWG (International Working Group) pour le domaine de la recherche. L’objecti f de cette étude est d’analyser la réalisation des examens complémentaires cités dans les critères NIA-AA et IWG au sein d’une clinique de la mémoire rassemblant une population hétérogène.Nous avons revu de manière rétrospective les caractéristiques de patients ayant consulté entre le 1/01/2010 et le 31/12/2013 selon 3 paramètres : la réalisation ou non de l’examen neuropsychologique, du dosage de biomarqueurs dans le liquide céphalo-rachidien (LCR) et de l’imagerie par résonance magnétique cérébrale. Les patients ont ensuite été comparés selon leur origine.Sur les 919 dossiers analysés dans l’étude, 20 % des patients sont issus de l’immigration. Les migrants non européens ont reçu moins d’examens neuropsychologiques et plus de ponctions lombaires que les patients belges.Les biomarqueurs du LCR permettent de définir une composante diagnostique objective de la MA en supprimant les variables liées à la langue, la culture, la scolarité et l’expression de la maladie. Malgré leur application connue dans le domaine de la recherche mais actuellement non validée en clinique, les critères IWG prédominent en pratique dans les populations hétérogènes comprenant un haut taux de migrants lorsque les examens neuropsychologiques sont peu contributifs. Des recommandations d’utilisation des biomarqueurs du LCR en pratique courante ou des outils d’évaluation cognitive plus performants dans ces types de population sont attendues.

The Huisgen thermal reaction between an organic azide and an acetylene was employed for the selective monofunctionalization of a X6 -azacryptand ligand bearing a tren coordinating unit [X6 stands for calix[6]arene and tren for tris(2-aminoethyl)amine]. Supramolecular assistance, originating from the formation of a host-guest inclusion complex between the reactants, greatly accelerates the reaction while self-inhibition affords a remarkable selectivity. The new ligand possesses a single amino-leg appended at the large rim of the calixarene core and the corresponding Zn(2+) complex was characterized both in solution and in the solid state. The coordination of Zn(2+) not only involves the tren cap but also the introverted amino-leg, which locks the metal ion in the cavity. Compared with the parent ligand deprived of the amino-leg, the affinity of the new monofunctionalized X6 tren ligand 6 for Zn(2+) is found to have a 10-fold increase in DMSO, which is a very competitive solvent, and with an enhancement of at least three orders of magnitude in CDCl3 /CD3 OD (1:1, v/v). In strong contrast with the fast binding kinetics, decoordination of Zn(2+) as well as transmetallation appeared to be very slow processes. The monofunctionalized X6 tren ligand 6 fully protects the metal ion from the external medium thanks to the combination of a cavity and a closed coordination sphere, leading to greater thermodynamic and kinetic stabilities.

Calixarenes are widely used as molecular platforms in supramolecular chemistry. Their efficient modification is key for appending functional moieties such as binding, sensing, chiral, or hydrophilic subunits. Due to the presence of multiple identical functional groups, selective functionalization of such macrocyclic compounds is highly challenging. Indeed, the control of the chemo-, regio-, stereo- as well as iteroselectivity is required. This review describes rational methods leading to a high degree of regio- and/or iteroselectivity and classifies them into specific strategies. Many of these strategies are conceptually very general and hopefully will be a source of inspiration for developing selective methods for other macrocyclic platforms.

Water is a unique solvent and the design of selective artificial hosts that can efficiently work in an aqueous medium is a challenging task. It is known that the calix[6]tren zinc complex can recognize neutral guests in organic solvents. This complex was incorporated into dodecylphosphocholine micelles (DPC) and studied by NMR. The incorporated complex is able to extract selectively primary amines from the aqueous environment driven by an important hydrophobic effect which also affects the selectivity of the complex for these amines. This work shows how the incorporation of organo-soluble receptors in micelles can be an elegant and very efficient strategy to obtain water compatible nanosized supramolecular recognition devices which can be prepared via a straightforward self-assembly process., info:eu-repo/semantics/published

The selective functionalization of macrocyclic receptors remains extremely challenging because it generally requires the transformation of one and only one functional group among several identical groups. Recently, some of us described that the host-guest properties of a calix[6]arene-based Zn complex could be exploited for its selective monofunctionalization. Herein, we report on the extension of this synthetic strategy to a calix[6]arene-based receptor displaying a different recognition pattern with its guest. More precisely, a calix[6]arene tris-carboxylic acid-based receptor bearing three azido groups at the large rim was selectively monofunctionalized through an intramolecular thermal Huisgen reaction with a hexynNH3(+) ion accommodated into the cavity. This work shows that the monofunctionalization methodology can also be performed efficiently with host-guest systems involving ionic/H-bonding interactions, and it is thus not limited only to the use of metal-ligand interactions. In other words, this supramolecular methodology can be used as a general tool for the selective functionalization of molecular receptors.