A new ganglioside containing an inner ester linkage was extracted from adult brain specimens, obtained at the time of surgery on 51-70-year-old subjects, purified, and analyzed. It contains glucose, galactose, N-acetylgalactosamine, an N-acetylneuraminic acid in the molar ratio 1:2:1:2, but, on ion-exchange chromatography, behaves as a monosialoganglioside. Structural analyses showed its basic neutral glycosphingolipid core to be ganglio-N-tetraose ceramide, carrying a disialosyl residue on the 3-position of internal galactose. Sialidase degradation and chemical analysis of the products obtained after alkaline treatments suggested one sialic acid residue to be involved in an ester linkage. Fast atom bombardment-mass spectrometry indicated the presence of an inner ester linkage between the carboxyl group of the external sialic acid residue and a hydroxyl group of the internal one. On these bases, the new ganglioside can be assumed to be a GD1b in lactonic form. This ganglioside is present only in trace amounts in the brain of infants, but its content increases with age, reaching a value of 3.5% of total sialic acid in 51-70-year-old subjects.
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Pharmaceutics
January 2025
Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
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State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China. Electronic address:
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School of Chemistry and Biochemistry, School of Materials Science and Engineering, Center for Organic Photonics and Electronics, Georgia Tech Polymer Network, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
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Laboratoire Sciences Analytiques, Bioanalytiques et Miniaturisation (LSABM), UMR CBI 8231 CNRS - ESPCI Paris PSL, Paris, France.
Corrosion inhibitors (CIs) are extensively employed in the oil and gas industry, yet their analysis remains a challenge. To develop a suitable liquid chromatography method for a wide array of CIs, a column screening was conducted. Nine different chromatographic conditions were tested across eight RPLC and mixed-mode columns (Accucore C18, CORTECS Shield RP18, Acquity HSS T3, Acquity Premier HSS T3, Accucore 150-C4, Accucore PFP, Synergi Polar RP, and Acclaim WCX-1).
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College of Horticultural and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010018, China.
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