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Rapid and sensitive pathogenic bacterial identification and isolation from complicated clinical specimens are of great importance for the early diagnosis and prevention of osteomyelitis. Herein, we proposed a novel methicillin-resistant Staphylococcus aureus (MRSA) detection strategy through two specially designed streptavidin magnetic bead-based probes, including a capture probe and a report probe. In detail, the capture probe takes the responsibility to specially bind with the surface protein of MRSA and leads to the liberation of the promoter which could subsequently initiate report probe-based signal amplification. Afterward, the hybridization of the promoter probe with the report probe could then transform the protruding 3' terminus of template DNA in the report probe into a blunt end. With the assistance of Exo III, the template could be digested to liberate the promoter to form a recycle and to liberate the biprobe to induce the following rolling circle amplification (RCA)-based signal amplification. Through the integration of the Exo III-assisted recycle and RCA-based signal amplification, the proposed method exhibited a favorable detection performance.

Compositional characteristics of maceral and extractable organic matter (EOM) of the No. 10 coal from the Yueliangtian mine, Guizhou, Southwestern China, were analyzed by optical microscopy, gas chromatography (GC), and gas chromatography-mass spectrometry (GC-MS). The depositional conditions, thermodynamic effect, type and maturity of organic matter, and possible health hazards were evaluated. The random vitrinite reflectance (R o) is 1.01%, and the macerals are dominated by collodetrinite, inertodetrinite, collotelinite, and fusinite. The coal seam is a terrestrial sedimentary environment of the lower delta plain through the analysis of coal facies. Additionally, the extracted yield of EOM is 1.01%. The low ratio of saturated to aromatic fraction and the distribution of n-alkanes indicate that the coal-forming plants are primarily terrestrial higher plants. Typical isoprenoid biomarker parameters, including pristane/phytane (Pr/Ph), Pr/n-C17, and Ph/n-C18, reflect a weak oxidizing environment of coal. The hopanoid biomarkers, odd-even predominance index (OEP), and carbon preference index (CPI) reveal that the organic matter was mature. More than one hundred polycyclic aromatic compounds (PACs) were eluted and identified, and the phenanthrenes and naphthalenes account for a higher proportion. Thermodynamic stabilities play an essential role in the conversion of molecular structures, which support the relatively high contents of 2-methylnaphthalene, 2- and 3-methylphenanthrenes, and 2,6- and 2,7-dimethylphenanthrenes compared to their respective isomers. The oxygen-containing and sulfur-containing aromatic compounds also indicate the weak oxidization of the coal-formation environment, which is consistent with the results of isoprenoid biomarkers. Because of the carcinogenicity and mutagenicity of PACs, the distribution and toxic equivalency of PACs are briefly summarized.

Free fatty acid receptor 4 (FFAR4) has various physiological functions, including energy regulation and immunological homeostasis. We examined the only FFAR4 homologue in the Pacific oyster Crassostrea gigas (CgFFAR4), which functions as a sensor of long-chain fatty acids. CgFFAR4 is 1098 bp long and contains a seven-transmembrane G protein-coupled receptor domain. CgFFAR4 expression was high in the hepatopancreas, but it was downregulated after fasting, indicating that it plays an essential role in food digestion. Lipopolysaccharide stimulation downregulated CgFFAR4 level, probably as an immune response of the animal. Reduced glycogen level alongside decreased insulin receptor, insulin receptor substrate, and C. gigas glycogen synthase transcription levels after CgFFAR4 knockdown revealed that CgFFAR4 was involved in the regulation of fatty acid and glycogen levels via the insulin pathway. Accordingly, this is the first study on an invertebrate FFAR and provides new insights into the role of this receptor in immune response and nutritional control.

Herein, we describe the photocatalytic generation of nucleophilic aroyl radicals from simple aroyl chlorides as a universal and efficient cross-coupling strategy for the direct aroylation of heteroarenes. Furthermore, visible light-mediated direct alkylation of heteroarenes has also been achieved using unactivated bromoalkanes as radical precursors. These two strategies feature high functional group tolerance, exclusive regioselectivity for reaction at the more electrophilic position of heteroarenes, easily accessible substrates, and mild reaction conditions. Moreover, mechanism studies of two reactions are carried out to support our hypotheses.

Vegetable chips—beets, sweet potatoes, carrots, and parsnips fried like potato chips and sold separately or as a mixture—are an increasingly popular snack. Little data currently exists on acrylamide levels in these products, and there is sparse information on the free amino acid composition of these four vegetables, with asparagine, a precursor of acrylamide, being of interest. Acrylamide concentrations in 35 vegetable chip samples and free amino acids in two to three samples of each of the four vegetables were measured. Of the chip samples, nearly 70% (24 samples) contained levels of acrylamide above the European Commission’s benchmark value of 750 µg/kg for potato chips. In comparison, from 2012 to 2016, approximately 10% of potato chip samples exceeded this value. The food industry has reduced the acrylamide content of potato chips by using cultivars developed specifically for chip manufacturing. Because the vegetable chip market is still significantly smaller than the potato chip market, equivalent cultivar development has not yet occurred. Hence, it is more likely for vegetable chips to be high in acrylamide than potato chips.