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    BaCuTP$_2$ (T = Al, Ga, In): a semiconducting black sheep in the ThCr$_2$Si$_2$ intermetallic family
    (Royal Society of Chemistry, 2024) Sarkar, Arka; Porter, Andrew; Viswanathan, Gayatri; Yox, Philip; Earnest, Rae Ann; Wang, Jian; Rossini, Aaron J.; Kovnir, Kirill
    The ThCr$_2$Si$_2$ structure type has been well explored for decades with diverse magnetic, superconducting, and heavy-fermion behavior. For transition metal-containing ThCr$_2$Si$_2$-type compounds, a metallic band structure and properties are typical. In this work, a rare example of semiconducting BaCuTP$_2$ (T = Al, Ga, In) materials is reported. BaCuTP$_2$ materials retain the tetragonal I4/mmm ThCr$_2$Si$_2$-type crystal structure with a large c/a ratio of ∼3.3, where Cu and T metals jointly occupy the Cr-site. Edge-sharing (Cu/T)P$_4$ tetrahedra form [CuTP$_2$]$^{2-}$ layers stacked along the crystallographic [001] direction, with the Ba$^{2+}$ cations located in the interlayer spaces. Solid state NMR revealed partial short-range ordering in the Cu/T sublattice. The composition of the produced phases is electron balanced, Ba$^{2+}$Cu$^{1+}$T$^{3+}$(P$^{3-}$)$_2$. High values of Seebeck coefficients were experimentally observed due to the high valley degeneracy in the band structure. Heat capacity and structural studies show that Ba exhibits anisotropic 'rattling-like' behavior along the [001] direction in Ga- and In-containing compounds. A combination of Ba rattling, short range Cu/T ordering, and a recently discovered coupling between acoustic and optical phonons for ThCr$_2$Si$_{2}$-type phosphides, resulted in ultralow thermal conductivity (<0.50 W m$^{-1}$ K$^{-1}$) for the title compounds. © 2024 The Royal Society of Chemistry.
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    Potent small molecule inhibitors against the 3C protease of foot- and-mouth disease virus
    (American Society for Microbiology, 2024) Kim, Yunjeong; Pool, Emma; Kim, Eunji; Dampalla, Chamandi S.; Nguyen, Harry Nhat; Johnson, David K.; Lovell, Scott; Groutas, William C.; Chang, Kyeong-Ok
    Foot-and-mouth disease (FMD) is one of the most devastating diseases of livestock which can cause significant economic losses, especially when introduced to FMD-free countries. FMD virus (FMDV) belongs to the family Picornaviridae and is antigenically heterogeneous with seven established serotypes. The prevailing preventive and control strategies are limited to restriction of animal movement and elimination of infected or exposed animals, which can be potentially combined with vaccination. However, FMD vaccination has limitations including delayed protection and lack of cross-protection against different serotypes. Recently, antiviral drug use for FMD outbreaks has increasingly been recognized as a potential tool to augment the existing early response strategies, but limited research has been reported on potential antiviral compounds for FMDV. FMDV 3C protease (3Cpro) cleaves the viral-encoded polyprotein into mature and functional proteins during viral replication. The essential role of viral 3Cpro in viral replication and the high conservation of 3Cpro among different FMDV serotypes make it an excellent target for antiviral drug development. We have previously reported multiple series of inhibitors against picornavirus 3Cpro or 3C-like proteases (3CLpros) encoded by coronaviruses or caliciviruses. In this study, we conducted structure-activity relationship studies for our in-house focused compound library containing 3Cpro or 3CLpro inhibitors against FMDV 3Cpro using enzyme and cell-based assays. Herein, we report the discovery of aldehyde and ?-ketoamide inhibitors of FMDV 3Cpro with high potency. These data inform future preclinical studies that are related to the advancement of these compounds further along the drug development pathway. Copyright © 2024 Kim et al.
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    Water-soluble phenolics from Phoenix dactylifera fruits as potential reno-protective agent against cisplatin-induced toxicity: pre- and post-treatment strategies
    (Taylor and Francis Ltd., 2024) Adewale, Omowumi Oyeronke; Oyelola, Roseline Fadera; Adetuyi, Oluwatosin; Adebisi, Oluwaseun Abraham; Adekomi, Damilare Adedayo; Oladele, Johnson Olaleye
    Nephrotoxicity is the major side effect of cisplatin, an effective platinum-based chemotherapeutic drug that is applicable in the treatment of several solid-tissue cancers. Studies have indicated that certain water-soluble phenolics offer renal protection. Thus, this study investigates the role of pre and post-treatment of rats with water-soluble phenolics from Phoenix dactylifera (PdP) against nephrotoxicity induced by cisplatin. Rats were either orally pretreated or post-treated with 200 mg/kg body weight of PdP before or after exposure to a single therapeutic dose of cisplatin (5 mg/kg body weight) for 7 successive days intraperitoneally. The protective effects of PdP against Cisplatin-induced nephrotoxicity was based on the evaluation of various biochemical and redox biomarkers, together with histopathological examination of kidney tissues. The composition, structural features, and antioxidative influence of PdP were determined based on chromatographic, spectroscopic, and in vitro antioxidative models. Cisplatin single exposure led to a substantial increase in the tested renal function biomarkers (uric acid, creatinine, and urea levels), associated with an increase in malondialdehyde indicating lipid peroxidation and a significant decline (p < 0.05) in reduced glutathione (GSH) levels in the renal tissue when compared with the control group. A marked decline exists in the kidney antioxidant enzymes (catalase, SOD, and GPx). Nevertheless, treatment with PdP significantly suppressed the heightened renal function markers, lipid peroxidation, and oxidative stress. Spectroscopic analysis revealed significant medicinal phenolics, and in vitro tests demonstrated antioxidative properties. Taken together, results from this study indicate that pre- and/or post-treatment strategies of PdP could serve therapeutic purposes in cisplatin-induced renal damage. © 2024 Informa UK Limited, trading as Taylor & Francis Group.
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    Sensitive detection of herbicide residues using field-amplified sample injection coupled with electrokinetic supercharging in flow-gated capillary electrophoresis
    (Royal Society of Chemistry, 2024) Gong, Ying; Gong, Maojun
    Residues of glyphosate (GlyP) and its major degradation product, aminomethylphosphonic acid (AMPA), widely exist in the water system and plant products and thus are also present in the bodies of animals and humans. Although no solid evidence has been obtained, the concern about the cancer risk of GlyP is persistent. The measurement of GlyP and AMPA in trace levels is often needed but lacks readily available analytical approaches with detection sensitivity, accuracy and speed. This study aims to develop a simple and robust technique for the sensitive detection of GlyP and AMPA residues in a surface water system with flow-gated capillary electrophoresis (CE). Experimentally, water samples were first fluorogenically derivatized with 4-fluoro-7-nitrobenzofurazan (NBD-F) in a low-conductivity buffer at room temperature, and the mixture was injected and concentrated in the capillary based on field-amplified sample injection (FASI) coupled with electrokinetic supercharging (EKS). This scheme included a step of sample buffer injection upon electroosmotic pumping, where negatively charged analytes were electrophoretically rejected, followed by automatic voltage reversal for FASI-EKS. The detection sensitivity was improved by 296, 444, and 861 times for glufosinate (GluF), AMPA, and GlyP, respectively. The proposed method was validated in terms of accuracy, precision, limits of detection (LODs), and linearity. The LODs were estimated to be 50.0 pM, 5.0 pM, and 10.0 pM for GluF, AMPA, and GlyP, respectively. Its application was demonstrated by measuring GluF and AMPA in water samples collected from a local water system. This study provides an effective approach for the online preconcentration of negatively charged analytes, thus enabling the sensitive detection of herbicide residues in water samples. The method can also be applied to analyze other samples, including biological fluids and plant products, upon appropriate sample preparation such as solid phase extraction of analytes. © 2024 The Royal Society of Chemistry.
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    Expanding Differential Ion Mobility Separations into the MegaDalton Range
    (American Chemical Society, 2023) Wörner, Tobias P.; Thurman, Hayden A.; Makarov, Alexander A.; Shvartsburg, Alexandre A.
    Along with mass spectrometry (MS), ion mobility separations (IMS) are advancing to ever larger biomolecules. The emergence of electrospray ionization (ESI) and native MS enabled the IMS/MS analyses of proteins up to ∼100 kDa in the 1990s and whole protein complexes and viruses up to ∼10 MDa since the 2000s. Differential IMS (FAIMS) is substantially orthogonal to linear IMS based on absolute mobility K and offers exceptional resolution, unique selectivity, and steady filtering readily compatible with slower analytical methods such as electron capture or transfer dissociation (ECD/ETD). However, the associated MS stages had limited FAIMS to ions with m/z < 8000 and masses under ∼300 kDa. Here, we integrate high-definition FAIMS with the Q-Exactive Orbitrap UHMR mass spectrometer that can handle m/z up to 80,000 and MDa-size ions in the native ESI regime. In the initial evaluation, the oligomers of monoclonal antibody adalimumab (148 kDa) are size-selected up to at least the nonamers (1.34 MDa) with m/z values up to ∼17,000. This demonstrates the survival and efficient separation of noncovalent MDa assemblies in the FAIMS process, opening the door to novel analyses of the heaviest macromolecules. © 2024 American Chemical Society.