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The purine alkaloid caffeine is the most widely consumed psychostimulant drug in the world and has multiple beneficial pharmacological activities, for example, in neurodegenerative diseases. However, despite being an extensively studied bioactive natural product, the mechanistic understanding of caffeine's pharmacological effects is incomplete. While several molecular targets of caffeine such as adenosine receptors and phosphodiesterases have been known for decades and inspired numerous medicinal chemistry programs, new protein interactions of the xanthine are continuously discovered providing potentially improved pharmacological understanding and a molecular basis for future medicinal chemistry. In this Perspective, we gather knowledge on the confirmed protein interactions, structure activity relationship, and chemical biology of caffeine on well-known and upcoming targets. The diversity of caffeine's molecular activities on receptors and enzymes, many of which are abundant in the CNS, indicates a complex interplay of several mechanisms contributing to neuroprotective effects and highlights new targets as attractive subjects for drug discovery.Multicellular systems possess an intrinsic capacity to autonomously generate nonrandom state distributions or morphologies in a process termed self-organization. Facets of self-organization, such as pattern formation, pattern elaboration, and symmetry breaking, are frequently observed in developing embryos. Artificial stem cell-derived structures including embryoid bodies (EBs), gastruloids, and organoids also demonstrate self-organization, but with a limited capacity compared to their in vivo developmental counterparts. There is a pressing need for better tools to allow user-defined control over self-organization in these stem cell-derived structures. Here, we employ synthetic biology to establish an efficient platform for the generation of self-organizing coaggregates, in which HEK-293 cells overexpressing P-cadherin (Cdh3) spontaneously form cell clusters attached mostly to one or two locations on the exterior of EBs. These Cdh3-expressing HEK cells, when further engineered to produce functional mouse WNT3A, evoke polarized and gradual Wnt/β-catenin pathway activation in EBs during coaggregation cultures. The localized WNT3A provision induces nascent mesoderm specification within regions of the EB close to the Cdh3-Wnt3a-expressing HEK source, resulting in pattern elaboration and symmetry breaking within EBs. This synthetic biology-based approach puts us closer toward engineering synthetic organizers to improve the realism in stem cell-derived structures.Particulate materials with well-engineered properties are of key importance for many aspects in our daily life. Polymer powders with high flowability, for example, play a crucial role in the emerging field of powder-based additive manufacturing processes. RTA-408 However, the polymer- and composite material selection for these technologies is still limited. Here, we demonstrate the design of spherical polymethyl methacrylate (PMMA) and PMMA-SiO2 composite supraparticle powders with excellent powder flowability and tailored composition for powder-based additive manufacturing. Our process assembles these powders from the bottom up and affords a precise control over surface roughness and internal morphology via the choice of colloidal primary particles. We establish process-structure-property relationships connecting external spray-drying parameters and primary particle sizes with the resulting supraparticle roughness and, subsequently, with the macroscopic powder flowability and powder bed density. In a second step, we demonstrate the control of composition and internal morphology of PMMA-SiO2 composite supraparticles based on different mass mixings and diameter ratios of the two primary particle dispersions. Finally, we successfully apply the prepared supraparticle powders in powder bed additive manufacturing. The optimized flowability of the composite powders allows the production of two-layered square specimens with fusion between the individual layers and a uniform and tunable distribution of nanoscale SiO2 additives without requiring the addition of any flowing aids.Biofilm formation and hemolysis induced by Staphylococcus aureus are closely related to pathogenicity. However, no drugs exist to inhibit biofilm formation or hemolysis induced by S. aureus in clinical practice. This study found diclazuril had antibacterial action against S. aureus with minimum inhibitory concentrations (MICs) at 50 μM for both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). Diclazuril (at 1/4× or 1/8× MICs) significantly inhibited biofilm formation of S. aureus under static or flow-based conditions and also inhibited hemolysis induced by S. aureus. The RNA levels of transcriptional regulatory genes (agrA, agrC, luxS, sarA, sigB, saeR, saeS), biofilm formation-related genes (aur, bap, ccpA, cidA, clfA, clfB, fnbA, fnbB, icaA, icaB, sasG), and virulence-related genes (hla, hlb, hld, hlg, lukDE, lukpvl-S, spa, sbi, alpha-3 PSM, beta PSM, coa) of S. aureus were decreased when treated by diclazuril (at 1/4× MIC) for 4 h. The diclazuril nonsensitive clones of S. aureus were selected in vitro by induction of wildtype strains for about 90 days under the pressure of diclazuril. Mutations in the possible target genes of diclazuril against S. aureus were detected by whole-genome sequencing. This study indicated that there were three amino acid mutations in the diclazuril nonsensitive clone of S. aureus, two of which were located in genes with known function (SMC-Scp complex subunit ScpB and glyceraldehyde-3-phosphate dehydrogenase 1, respectively) and one in a gene with unknown function (hypothetical protein). Diclazuril showed a strong inhibition effect on planktonic cells and biofilm formation of S. aureus with the overexpression of the scpB gene.Three-dimensional (3D) cell culture can better reproduce the in vivo cell environment and has been extensively used in fields such as tissue engineering, drug screening, and pathological research. Despite the tremendous advancement of 3D cultures, an analysis technique that could collect real-time information of the biological processes therein is sorely lacking. Electrochemical sensing with fast response and high sensitivity has played a vital role in real-time monitoring of living cells, but most current sensors are based on planar electrodes and fail to perfectly match the 3D cell culture matrix. Herein, we developed a robust 3D electrochemical sensor based on functionalized graphene foam (GF), which could be integrated with hydrogels for the 3D culture and in situ monitoring of cells for the first time. Specifically, platinum nanoparticles (Pt NPs) electrodeposited on GF (GF/Pt NPs) conferred the prominent electrochemical sensing performance, and the anti-fouling coating of poly(3,4-ethylenedioxythiophene) (PEDOT) endowed the GF/Pt NPs electrode with greatly improved stability.