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It was found that both the basicity and molecular size of the anion play key roles in the formation of the phosphonium ylide. In the extreme case of [P66614][4-Triaz] only half of the reacted product was the desired carbamate at 60 °C. Although there is a significant amount of the carboxyl product formed, the carbamate is kinetically favored.Prediction of skin absorption and local bioavailability from topical formulations remains a difficult task. An important challenge in forecasting topical bioavailability is the limited information available about local and systemic drug concentrations post application of topical drug products. Commercially available transdermal patches, such as Scopoderm (Novartis Consumer Health UK), offer an opportunity to test these experimental approaches as systemic pharmacokinetic data are available with which to validate a predictive model. The long-term research aim, therefore, is to develop a physiologically based pharmacokinetic model (PBPK) to predict the dermal absorption and disposition of actives included in complex dermatological products. This work explored whether in vitro release and skin permeation tests (IVRT and IVPT, respectively), and in vitro and in vivo stratum corneum (SC) and viable tissue (VT) sampling data, can provide a satisfactory description of drug "input rate" into the skin and subsequently into the systemic circulation. In vitro release and skin permeation results for scopolamine were consistent with the previously reported performance of the commercial patch investigated. New skin sampling data on the dermatopharmacokinetics (DPK) of scopolamine also accurately reflected the rapid delivery of a "priming" dose from the patch adhesive, superimposed on a slower, rate-controlled input from the drug reservoir. The scopolamine concentration versus time profiles in SC and VT skin compartments, in vitro and in vivo, taken together with IVRT release and IVPT penetration kinetics, reflect the input rate and drug delivery specifications of the Scopoderm transdermal patch and reveal the importance of skin binding with respect to local drug disposition. Further data analysis and skin PK modeling are indicated to further refine and develop the approach outlined.By the splendid advance in computation power realized with the Fugaku supercomputer, it has become possible to perform ab initio fragment molecular orbital (FMO) calculations for thousands of dynamic structures of protein-ligand complexes in a parallel way. We thus carried out electron-correlated FMO calculations for a complex of the 3C-like (3CL) main protease (Mpro) of the new coronavirus (SARS-CoV-2) and its inhibitor N3 incorporating the structural fluctuations sampled by classical molecular dynamics (MD) simulation in hydrated conditions. Along with a statistical evaluation of the interfragment interaction energies (IFIEs) between the N3 ligand and the surrounding amino-acid residues for 1000 dynamic structure samples, in this study we applied a novel approach based on principal component analysis (PCA) and singular value decomposition (SVD) to the analysis of IFIE data in order to extract the dynamically cooperative interactions between the ligand and the residues. We found that the relative importance of each residue is modified via the structural fluctuations and that the ligand is bound in the pharmacophore in a dynamic manner through collective interactions formed by multiple residues, thus providing new insight into structure-based drug discovery.Hydroxyethylamine (HEA)-based novel compounds were synthesized and their activity against Plasmodium falciparum 3D7 was assessed, identifying a few hits without any apparent toxicity. Hits 5c and 5d also exhibited activity against resistant field strains, PfRKL-9 and PfC580Y. A single dose, 50 mg/Kg, of hits administered to the rodent parasite Plasmodium berghei ANKA exhibited up to 70% reduction in the parasite load. Compound 5d tested in combination with artesunate produced an additional antiparasitic effect with a prolonged survival period. Additionally, compound 5d showed 50% inhibition against hepatic P. berghei infection at 1.56 ± 0.56 μM concentration. This compound also considerably delayed the progression of transmission stages, ookinete and oocyst. Furthermore, the toxicity of 5d assessed in mice supported the normal liver and kidney functions. Altogether, HEA analogues (5a-m), particularly 5d, are nontoxic multistage antiplasmodial agents with therapeutic and transmission-blocking efficacy, along with favorable preliminary pharmacokinetic properties.Our previous study showed that apple polyphenol extract (APE) ameliorated high-fat diet-induced hepatic steatosis in C57BL/6 mice by targeting the LKB1/AMPK pathway; to investigate whether other mechanisms are involved in APE induction of improved hepatic steatosis, especially the roles of bile acid (BA) metabolism and gut microbiota, we conducted this study. Thirty-three C57BL/6 male mice were fed with high-fat diet for 12 weeks and concomitantly treated with sterilized water (CON) or 125 or 500 mg/(kg·bw·day) APE (low-dose APE, LAP; high-dose APE, HAP) by intragastric administration. APE treatment decreased total fecal BA contents, especially fecal primary BA levels, mainly including cholic acid, chenodeoxycholic acid, and muricholic acid. An upregulated hepatic Farnesoid X receptor (FXR) protein level and downregulated protein levels of cholesterol 7α-hydroxylase (CYP7A1) and cholesterol 7α-hydroxylase (CYP27A1) were observed after APE treatment, which resulted in the suppressed BA synthesis. Meanwhile, APE had no significant effects on mucosal injury and FXR expression in the jejunum. APE regulated the diversity of gut microbiota and microbiota composition, characterized by significantly increased relative abundance of Akkermansia and decreased relative abundance of Lactobacillus. TGF-beta inhibitor review Furthermore, APE might affect the reverse cholesterol transport in the ileum, evidenced by the changed mRNA levels of NPC1-like intracellular cholesterol transporter 1 (Npc1l1), liver X receptor (Lxr), ATP binding cassette subfamily A member 1 (Abca1), and ATP binding cassette subfamily G member 1 (Abcg1). However, APE did not affect the dihydroxylation and taurine metabolism of BA. The correlation analysis deduced no obvious interactions between BA and gut microbiota. In summary, APE, especially a high dose of APE, could alleviate hepatic steatosis, and the mechanisms were associated with inhibiting BA synthesis and modulating gut microbiota.Entangled photon pairs have been used for molecular spectroscopy in the form of entangled two-photon absorption and in quantum interferometry for precise measurements of light source properties and time delays. We present an experiment that combines molecular spectroscopy and quantum interferometry by utilizing the correlations of entangled photons in a Hong-Ou-Mandel (HOM) interferometer to study molecular properties. We find that the HOM signal is sensitive to the presence of a resonant organic sample placed in one arm of the interferometer, and the resulting signal contains information pertaining to the light-matter interaction. We can extract the dephasing time of the coherent response induced by the excitation on a femtosecond time scale. A dephasing time of 102 fs is obtained, which is relatively short compared to times found with similar methods and considering line width broadening and the instrument entanglement time As the measurement is done with coincidence counts as opposed to simply intensity, it is unaffected by even-order dispersion effects, and because interactions with the molecular state affect the photon correlation, the observed measurement contains only these effects and no other classical losses. The experiments are accompanied by theory that predicts the observed temporal shift and captures the entangled photon joint spectral amplitude and the molecule's transmission in the coincidence counting rate. Thus, we present a proof-of-concept experimental method based of entangled photon interferometry that can be used to characterize optical properties in organic molecules and can in the future be expanded on for more complex spectroscopic studies of nonlinear optical properties.The peptide hormone glucagon is prescribed as a pharmaceutical compound to treat diabetic hypoglycemia. However, at the acidic pH where it is highly soluble, glucagon rapidly aggregates into inactive and cytotoxic amyloid fibrils. The recently determined high-resolution structure of these fibrils revealed various stabilizing molecular interactions. On the basis of this structure, we have now designed four arginine mutants of glucagon that resist fibrillization at pharmaceutical concentrations for weeks. An S2R, T29R double mutant and a T29R single mutant remove a hydrogen-bonding interaction in the wild-type fibril, whereas a Y13R, A19R double mutant and a Y13R mutant remove a cation-π interaction. 1H solution nuclear magnetic resonance spectra and ultraviolet absorbance data indicate that these mutants remain soluble in pH 2 buffer under quiescent conditions at concentrations of ≤4 mg/mL for weeks. Under stressed conditions with high salt concentrations and agitation, these mutants fibrillize significantly more slowly than the wild type. The S2R, T29R mutant and the T29R mutant exhibit a mixture of random coil and α-helical conformations, while the Y13R mutant is completely random coil. The mutation sites are chosen to be uninvolved in strong interactions with the glucagon receptor in the active structure of the peptide. Therefore, these arginine mutants of glucagon are promising alternative compounds for treating hypoglycemia.The somatosensory system helps the human body to become aware of various stimuli and to interact with its surroundings. Humans are able to identify and to process abundant sensory information quickly due to their unique perception characteristics. As the largest sensory organ, skin has a large number of discrete receptors to sense and to transform stimuli of touch, pressure, pain, temperature, etc. into electrical signals, which are preprocessed at various levels before reaching the brain, greatly reducing the computational burden on the central nervous system. In addition, the conduction speed varies for different stimulus information, which simplifies the parallel processing of a variety of information. In this Perspective, we discuss a bioinspired design for a flexible smart sensor system by simulating the human somatosensory system. In this design, sensors with selective responses, signals separated in time sequences, and hierarchical information processing are adopted to optimize the sensing and perceiving processes, to reduce power consumption, and to improve the speed of a flexible smart sensor system.Long-haul truck electrification has attracted nascent policy support, but the potential health and climate impacts remain uncertain. Here, we developed an integrated assessment approach with high spatial-temporal (km and hourly) resolution to characterize the causal chain from truck operation to charging loads, electricity grid response, changes in emissions and atmospheric concentrations, and the resulting health and climate impacts across the United States. Compared to future diesel trucks, electrified trucking's net health benefits are concentrated only along the West Coast with a business-as-usual electricity grid. However, with an 80%-renewable electricity grid, most regions would experience net health benefits, and the economic value of avoided climate and health damages exceeds $5 billion annually, an 80% reduction relative to future diesel trucks. Electric trucks with larger batteries may increase health and climate impacts due to additional trips needed to compensate for the payload penalty, but a 2× improvement in the battery specific energy (to ∼320 Wh/kg) could eliminate the additional trips.

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