Publications by authors named "Andreas Topp"

Purpose: The monoacylglycerol lipase (MAGL) plays a pivotal role in modulating the endocannabinoid system and is considered an attractive therapeutic target for diseases in both the central nervous system and periphery. The current study aimed to develop and evaluate a suitable carbon-11 labeled tracer for imaging MAGL in preclinical studies.

Methods: (R)-YH168 was synthesized via a multi-step pathway and its half-maximal inhibitory concentration (IC) values were measured using an enzymatic assay.

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Cell-free enzymatic assays are highly useful tools in early compound profiling due to their robustness and scalability. However, their inadequacy to reflect the complexity of target engagement in a cellular environment may lead to a significantly divergent pharmacology that is eventually observed in cells. The discrepancy that emerges from properties like permeability and unspecific protein binding may largely mislead lead compound selection to undergo further chemical optimization.

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Monoacylglycerol lipase (MAGL) is a key enzyme involved in the metabolism of the endogenous signaling ligand 2-arachidonoylglycerol, a neuroprotective endocannabinoid intimately linked to central nervous system (CNS) disorders associated with neuroinflammation. In the quest for novel MAGL inhibitors, a focused screening approach on a Roche library subset provided a reversible benzoxazinone hit exhibiting high ligand efficiency. The subsequent design of the three-dimensional -hexahydro-pyrido-oxazinone (-HHPO) moiety as benzoxazinone replacement enabled the combination of high MAGL potency with favorable ADME properties.

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This study aimed to evaluate ()-[F]YH134 as a novel PET tracer for imaging monoacylglycerol lipase (MAGL). Considering the ubiquitous expression of MAGL throughout the whole body, the impact of various MAGL inhibitors on ()-[F]YH134 brain uptake and its application in brain-periphery crosstalk were explored. MAGL knockout and wild-type mice were used to evaluate ()-[F]YH134 in in vitro autoradiography and PET experiments.

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Monoacylglycerol lipase (MAGL) is one of the key enzymes in the endocannabinoid system. Inhibition of MAGL has been proposed as an attractive approach for the treatment of various diseases. In this study, we designed and successfully synthesized two series of piperazinyl pyrrolidin-2-one derivatives as novel reversible MAGL inhibitors.

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New developments in the field of topological matter are often driven by materials discovery, including novel topological insulators, Dirac semimetals, and Weyl semimetals. In the last few years, large efforts have been made to classify all known inorganic materials with respect to their topology. Unfortunately, a large number of topological materials suffer from non-ideal band structures.

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Genetic, preclinical and clinical data link Parkinson's disease and Gaucher's disease and provide a rational entry point to disease modification therapy via enhancement of β-Glucocerebrosidase (GCase) activity. We discovered a new class of pyrrolo[2,3-b]pyrazine activators effecting both Vmax and Km. They bind to human GCase and increase substrate metabolism in the lysosome in a cellular assay.

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Principles that predict reactions or properties of materials define the discipline of chemistry. In this work, we derive chemical rules, based on atomic distances and chemical bond character, which predict topological materials in compounds that feature the structural motif of a square-net. Using these rules, we identify over 300 potential new topological materials.

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Van der Waals (vdW) materials with magnetic order have been heavily pursued for fundamental physics as well as for device design. Despite the rapid advances, so far, they are mainly insulating or semiconducting, and none of them has a high electronic mobility-a property that is rare in layered vdW materials in general. The realization of a high-mobility vdW material that also exhibits magnetic order would open the possibility for novel magnetic twistronic or spintronic devices.

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Transition-metal chalcogenides are a promising family of materials for applications as photocathodes in photoelectrochemical (PEC) H generation. A long-standing challenge for chalcopyrite semiconductors is characterizing their electronic structure, both experimentally and theoretically, because of their relatively high-energy band gaps and spin-orbit coupling (SOC), respectively. In this work, we present single crystals of CuInTe, whose relatively small optically measured band gap of 0.

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Recent interest in topological semimetals has led to the proposal of many new topological phases that can be realized in real materials. Next to Dirac and Weyl systems, these include more exotic phases based on manifold band degeneracies in the bulk electronic structure. The exotic states in topological semimetals are usually protected by some sort of crystal symmetry, and the introduction of magnetic order can influence these states by breaking time-reversal symmetry.

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The human protease family HtrA is responsible for preventing protein misfolding and mislocalization, and a key player in several cellular processes. Among these, HtrA1 is implicated in several cancers, cerebrovascular disease and age-related macular degeneration. Currently, HtrA1 activation is not fully characterized and relevant for drug-targeting this protease.

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Materials harbouring exotic quasiparticles, such as massless Dirac and Weyl fermions, have garnered much attention from physics and material science communities due to their exceptional physical properties such as ultra-high mobility and extremely large magnetoresistances. Here, we show that the highly stable, non-toxic and earth-abundant material, ZrSiS, has an electronic band structure that hosts several Dirac cones that form a Fermi surface with a diamond-shaped line of Dirac nodes. We also show that the square Si lattice in ZrSiS is an excellent template for realizing new types of two-dimensional Dirac cones recently predicted by Young and Kane.

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The antioxidant xanthophylls lutein and zeaxanthin are absorbed from the diet in a process involving lipoprotein formation. Selective mechanisms exist for their intestinal uptake and tissue-selective distribution, but these are poorly understood. We investigated the role of high-density lipoprotein (HDL), apolipoprotein (apo) A1 and ATP-binding cassette transporter (ABC) A1 in intestinal uptake of lutein in a human polarized intestinal cell culture and a hamster model.

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