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1.
Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver disorder, affecting around 25% of the population worldwide. It is a complex disease spectrum, closely linked with other conditions such as obesity, insulin resistance, type 2 diabetes mellitus, and metabolic syndrome, which may increase liver-related mortality. In light of this, numerous efforts have been carried out in recent years in order to clarify its pathogenesis and create new prevention strategies. Currently, the essential role of environmental pollutants in NAFLD development is recognized. Particularly, endocrine-disrupting chemicals (EDCs) have a notable influence. EDCs can be classified as natural (phytoestrogens, genistein, and coumestrol) or synthetic, and the latter ones can be further subdivided into industrial (dioxins, polychlorinated biphenyls, and alkylphenols), agricultural (pesticides, insecticides, herbicides, and fungicides), residential (phthalates, polybrominated biphenyls, and bisphenol A), and pharmaceutical (parabens). Several experimental models have proposed a mechanism involving this group of substances with the disruption of hepatic metabolism, which promotes NAFLD. These include an imbalance between lipid influx/efflux in the liver, mitochondrial dysfunction, liver inflammation, and epigenetic reprogramming. It can be concluded that exposure to EDCs might play a crucial role in NAFLD initiation and evolution. However, further investigations supporting these effects in humans are required.  相似文献   
2.
Apical membrane antigen 1 is a microneme protein which plays an indispensable role during Apicomplexa parasite invasion. The detailed mechanism of AMA-1 molecular interaction with its receptor on bovine erythrocytes has not been completely defined in Babesia bovis. This study was focused on identifying the minimum B. bovis AMA-1-derived regions governing specific and high-affinity binding to its target cells. Different approaches were used for detecting ama-1 locus genetic variability and natural selection signatures. The binding properties of twelve highly conserved 20-residue-long peptides were evaluated using a sensitive and specific binding assay based on radio-iodination. B. bovis AMA-1 ectodomain structure was modelled and refined using molecular modelling software. NetMHCIIpan software was used for calculating B- and T-cell epitopes. The B. bovis ama-1 gene had regions under functional constraint, having the highest negative selective pressure intensity in the Domain I encoding region. Interestingly, B. bovis AMA-1-DI (100YMQKFDIPRNHGSGIYVDLG119 and 120GYESVGSKSYRMPVGKCPVV139) and DII (302CPMHPVRDAIFGKWSGGSCV321)-derived peptides had high specificity interaction with erythrocytes and bound to a chymotrypsin and neuraminidase-treatment sensitive receptor. DI-derived peptides appear to be exposed on the protein’s surface and contain predicted B- and T-cell epitopes. These findings provide data (for the first-time) concerning B. bovis AMA-1 functional subunits which are important for establishing receptor-ligand interactions which could be used in synthetic vaccine development.  相似文献   
3.

The presence of Mn(II) in water exceeding the permitted concentration limits declared by the World Health Organization (WHO) influences individuals, animals, and the ecosystem negatively. Therefore, there is a necessity for an efficient material to eliminate this potentially toxic element from wastewater. We herein focused on the adsorptive removal of Mn(II) ions from polluted aqueous media using natural Egyptian glauconite clay (G) and its nanocomposites with modified chitosan (CS). We applied modified chitosan with glutaraldehyde (GL), ethylenediaminetetraacetic acid (EDTA), sodium dodecyl sulfate (SDS), and cetyltrimethyl ammonium bromide (CTAB). The utilized nanocomposites were referred to as GL-CS/G, EDTA-GL-CS/G, SDS-CS/G, and CTAB-CS/G, respectively. The point of zero charge values of the materials were estimated. The adsorption properties of the G clay and its nanocomposites toward the removal of Mn(II) ions from polluted aqueous media as well as the adsorption mechanism were explored using a batch technique. The glauconite (G) and its nanocomposites: GL-CS/G, CTAB-CS/G, EDTA-GL-CS/G, and SDS-CS/G, exhibited maximum adsorption capacity values of 3.60, 24.0, 26.0, 27.0, and 27.9 mg g?1, respectively. The adsorption results fitted well the Langmuir isotherm and pseudo-second-order kinetic models. The estimated thermodynamic parameters: ΔH° (from 1.03 to 5.55 kJ/mol) and ΔG° (from ? 14.5 to ? 18.8 kJ/mol), indicated that Mn(II) ion adsorption process was endothermic, spontaneous, and physisorption controlled. Furthermore, the obtained adsorption results are encouraging and revealing a great potentiality for using the modified adsorbents as accessible adsorbents for Mn(II) ion removal from polluted aqueous solutions, depending on their reusability, high stability, and good adsorption capacities.

Graphic Abstract
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4.
Nutrient Cycling in Agroecosystems - Reducing agriculturally derived diffuse contaminant losses (via non-point sources) from land to water has proven difficult for decades. Owing to the diversity...  相似文献   
5.
Inhibition of PSD-95 has emerged as a promising strategy for the treatment of ischemic stroke, as shown with peptide-based compounds that target the PDZ domains of PSD-95. In contrast, developing potent and drug-like small molecules against the PSD-95 PDZ domains has so far been unsuccessful. Here, we explore the druggability of the PSD-95 PDZ1-2 domain and use fragment screening to investigate if this protein is prone to binding small molecules. We screened 2500 fragments by fluorescence polarization (FP) and validated the hits by surface plasmon resonance (SPR), including an inhibition counter-test, and found four promising fragments. Three ligand efficient fragments were shown by 1H,15N HSQC NMR to bind in the small hydrophobic P0 pockets of PDZ1-2, and one of them underwent structure-activity relationship (SAR) studies. Overall, we demonstrate that fragment screening can successfully be applied to PDZ1-2 of PSD-95 and disclose novel fragments that can serve as starting points for optimization towards small-molecule PDZ domain inhibitors.  相似文献   
6.
Chameleonic properties, i. e., the capacity of a molecule to hide polarity in non-polar environments and expose it in water, help achieving sufficient permeability and solubility for drug molecules with high MW. We present models of experimental measures of polarity for a set of 24 FDA approved drugs (MW 405-1113) and one PROTAC (MW 1034). Conformational ensembles in aqueous and non-polar environments were generated using molecular dynamics. A linear regression model that predicts chromatographic apparent polarity (EPSA) with a mean unsigned error of 10 Å2 was derived based on separate terms for donor, acceptor, and total molecular SASA. A good correlation (R2=0.92) with an experimental measure of hydrogen bond donor potential, Δlog Poct-tol, was found for the mean hydrogen bond donor SASA of the conformational ensemble scaled with Abraham's A hydrogen bond acidity. Two quantitative measures of chameleonic behaviour, the chameleonic efficiency indices, are introduced. We envision that the methods presented herein will be useful to triage designed molecules and prioritize those with the best chance of achieving acceptable permeability and solubility.  相似文献   
7.
Silicon - Feeling prone to stress differs with plant production stage, water scarcity near commencement of grain filling phase has a significant reduced grain yield through fewer endosperm and sink...  相似文献   
8.
Cell encapsulation within hydrogel droplets is transforming what is feasible in multiple fields of biomedical science such as tissue engineering and regenerative medicine, in vitro modeling, and cell-based therapies. Recent advances have allowed researchers to miniaturize material encapsulation complexes down to single-cell scales, where each complex, termed a single-cell microgel, contains only one cell surrounded by a hydrogel matrix while remaining <100 μm in size. With this achievement, studies requiring single-cell resolution are now possible, similar to those done using liquid droplet encapsulation. Of particular note, applications involving long-term in vitro cultures, modular bioinks, high-throughput screenings, and formation of 3D cellular microenvironments can be tuned independently to suit the needs of individual cells and experimental goals. In this progress report, an overview of established materials and techniques used to fabricate single-cell microgels, as well as insight into potential alternatives is provided. This focused review is concluded by discussing applications that have already benefited from single-cell microgel technologies, as well as prospective applications on the cusp of achieving important new capabilities.  相似文献   
9.
The direct-synthesis of conductive PbS quantum dot (QD) ink is facile, scalable, and low-cost, boosting the future commercialization of optoelectronics based on colloidal QDs. However, manipulating the QD matrix structures still is a challenge, which limits the corresponding QD solar cell performance. Here, for the first time a coordination-engineering strategy to finely adjust the matrix thickness around the QDs is presented, in which halogen salts are introduced into the reaction to convert the excessive insulating lead iodide into soluble iodoplumbate species. As a result, the obtained QD film exhibits shrunk insulating shells, leading to higher charge carrier transport and superior surface passivation compared to the control devices. A significantly improved power-conversion efficiency from 10.52% to 12.12% can be achieved after the matrix engineering. Therefore, the work shows high significance in promoting the practical application of directly synthesized PbS QD inks in large-area low-cost optoelectronic devices.  相似文献   
10.
Wireless Personal Communications - This research work explores the neural network learning capabilities by using a multi-layer perceptron artificial neural network to predict signal power loss by...  相似文献   
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