Post-prandial increases in liver-gut hormone LEAP2 correlate with attenuated eating behaviour in adults without obesity

Background: The novel liver-gut hormone LEAP2 is a centrally acting inverse agonist, and competitive antagonist of orexigenic acyl ghrelin (AG), at the growth hormone secretagogue receptor, reducing food intake in rodents. In humans, the effects of LEAP2 on eating behaviour and mechanisms behind the post-prandial increase in LEAP2 are unclear, though this is reciprocal to the post-prandial decrease in plasma AG. Methods: Plasma LEAP2 was measured in a secondary analysis of a previous study. Twenty-two adults without obesity attended after an overnight fast (Fasted-saline), consuming a 730kcal meal without (Fed-saline) or with (Fed-ghrelin) subcutaneous AG administration. Post-prandial changes in plasma LEAP2 were correlated with post-prandial changes in appetite, high-energy (HE) or low-energy (LE) food cue reactivity using functional MRI, ad libitum food intake, and plasma/serum AG, glucose, insulin and triglycerides. Results: Post-prandial plasma LEAP2 increased by 24.5-52.2% at 70-150 min, but was unchanged by exogenous AG administration. Post-prandial increases in LEAP2 correlated positively with post-prandial decreases in appetite, and cue reactivity to HE/LE and HE food in anterior/posterior cingulate cortex, paracingulate cortex, frontal pole, middle frontal gyrus, with similar trend for food intake. Post-prandial increases in LEAP2 correlated negatively with body mass index, but did not correlate positively with increases in glucose, insulin or triglycerides, nor decreases in AG. Conclusions: These correlational findings are consistent with a role for post-prandial increases in plasma LEAP2 in suppressing human eating behaviour in adults without obesity. Post-prandial increases in plasma LEAP2 are unrelated to changes in plasma AG and the mediator(s) remain uncertain

Metal oxide and bimetallic nanoparticles in ionic liquids: synthesis and application in multiphase catalysis

Ionic liquids (ILs) are well established as solvents and stabilizing agents for the synthesis of metallic nanoparticles (NPs) in general. The physicochemical properties of ILs and the supramolecular organization in the liquid state are capable of directing the growth of transition metal NPs generated in situ and to subsequently protect and stabilize them. Until now, many different NPs have been successfully synthesized within these media; however, the synthesis of metal oxide and bimetallic alloy or core-shell NPs in ILs is still relatively rare. Herein, we summarize the current state-of-the-art of the synthetic methods for these materials and their application in the broad field of catalysis, including multiphase systems, hydrogenation, dehydrogenation, functionalization, as well as defunctionalization reactions

Ligand-free copper(I) oxide nanoparticle-catalysed amination of aryl halides in ionic liquids

In the following, we present a simple and feasible methodology for a C-N coupling reaction using nanoscale Cu2O catalysts incorporated in n-Bu4POAc ionic liquid media. It is shown that a wide range of amines and aryl halides can be coupled selectively in high yields, without the use of ligands or additives (bases) and without precautions against water or air. All catalyses can be carried out with a nanoparticle catalyst loading as low as 5 mol%, based on the used precursor

A mental number line in human newborns

Humans represent numbers on a mental number line with smaller numbers on the left and larger numbers on the right side. A left\u2010to\u2010right oriented spatial\u2013numerical association, (SNA), has been demonstrated in animals and infants. However, the possibility that SNA is learnt by early exposure to caregivers\u2019 directional biases is still open. We conducted two experiments: in Experiment 1, we tested whether SNA is present at birth and in Experiment 2, we studied whether it depends on the relative rather than the absolute magnitude of numerousness. Fifty\u2010five\u2010hour\u2010old newborns, once habituated to a number (12), spontaneously associated a smaller number (4) with the left and a larger number (36) with the right side (Experiment 1). SNA in neonates is not absolute but relative. The same number (12) was associated with the left side rather than the right side whenever the previously experienced number was larger (36) rather than smaller (4) (Experiment 2). Control on continuous physical variables showed that the effect is specific of discrete magnitudes. These results constitute strong evidence that in our species SNA originates from pre\u2010linguistic and biological precursors in the brain

Stacking Polymorphism in PtSe2 Drastically Affects Its Electromechanical Properties

PtSe2 is one of the most promising materials for the next generation of piezoresistive sensors. However, the large-scale synthesis of homogeneous thin films with reproducible electromechanical properties is challenging due to polycrystallinity. It is shown that stacking phases other than the 1T phase become thermodynamically available at elevated temperatures that are common during synthesis. It is shown that these phases can make up a significant fraction in a polycrystalline thin film and discuss methods to characterize them, including their Seebeck coefficients. Lastly, their gauge factors, which vary strongly and heavily impact the performance of a nanoelectromechanical device are estimated

Molecular Palladium Precursors for Pd0 Nanoparticle Preparation by Microwave Irradiation: Synthesis, Structural Characterization and Catalytic Activity

Two new palladium complexes [Pd(MEA)2Cl2] (1) and [Pd(MEA)2Br2] (2) [MEA = (2-methoxyethyl)amine] were synthesized by the reaction of 2 equiv. of MEA with PdCl2 or [(cod)PdBr2] (cod = cycloocta-1,5-diene), respectively. Single-crystal X-ray diffraction analysis of 1 and 2 revealed the formation of square-planar trans complexes with palladium coordinated by chloride/bromide ions and N-atoms of MEA bonded in a monodentate fashion. Given their molecular form and solubility, 1 and 2 act as intractable precursors to Pd nanoparticles by microwave-assisted synthesis. The influence of the reaction temperature, irradiation time and surfactant (PVP) concentration on the size (540 nm) of the resulting particles was studied by DLS (hydrodynamic diameter) and TEM analyses (particle size). The growth mechanism of the nanoparticles depended on the type of halide ligand. Powder X-ray diffractometry confirmed the formation of elemental Pd particles that were embedded in carbonized wood to examine their potential as a catalyst. The catalytic activity of these nanoscale particles was evaluated in carboncarbon cross-coupling reactions by using Heck, Suzuki and Sonogashira reactions as benchmark models. The investigations included recycling experiments that resulted in total turnover numbers of 4321 (Heck), 6173 (Sonogashira) and 8223 (Suzuki)