Cognitive impairment and dementia are public health concerns with significant financial implications for both individual households and public insurance systems. Though research has refined diagnostic tools for cognitive impairment and dementia diseases, little attention has focused on how cognitive decline may impact financial security. Research indicates that financial decision-making may be one of the first cognitive abilities impacted by cognitive decline, putting individuals at risk of financial fraud and exploitation.
View Article and Find Full Text PDFThe contamination of the widely used lifesaving anticoagulant drug heparin in 2007 has drawn renewed attention to the challenges that are associated with the characterization, quality control and standardization of complex biological medicines from natural sources. Heparin is a linear, highly sulfated polysaccharide consisting of alternating glucosamine and uronic acid monosaccharide residues. Heparin has been used successfully as an injectable antithrombotic medicine since the 1930s, and its isolation from animal sources (primarily porcine intestine) as well as its manufacturing processes have not changed substantially since its introduction.
View Article and Find Full Text PDFJ Am Soc Mass Spectrom
November 2014
Simple alcohols formed protonated acetonitrile adducts containing up to two acetonitrile molecules when analyzed by ESI or APCI in the presence of acetonitrile in the solvent. These acetonitrile adducts underwent dissociation to form a nitrilium ion, also referred to as the substitution ion. Diols and triols behaved differently.
View Article and Find Full Text PDFThe overall structure of pertussis toxoid has been established by analysis of its tryptic digest using two-dimensional liquid chromatography-tandem mass spectrometry (2D-LC-MS/MS), capillary liquid chromatography-matrix-assisted laser desorption ionization-tandem mass spectrometry (CapLC-MALDI-MS/MS), and ultraperformance liquid chromatography-mass spectrometry(E) (UPLC-MS(E)). In addition to oxidation and hydrolysis of amino acids losses of terminal peptides are observed. On-line UPLC-MS(E) generated a similar sequence coverage as the other two methods that involved off-line fraction collection.
View Article and Find Full Text PDFIn late 2007 and early 2008, a cluster of adverse events in patients receiving Heparin Sodium Injection occurred in the United States and in some countries in Europe. The adverse events were reported as being "allergic type" reactions, chiefly characterized by acute hypotension, nausea, and shortness of breath. The root cause of the cluster of adverse events was determined to be a contamination of the heparin by oversulfated chondroitin sulfate.
View Article and Find Full Text PDFMonosaccharide analysis is a critical way to profile the composition of complex carbohydrates. Methods to analyze neutral and amino sugars have been established for a long time, but methods for acidic sugars are rare. The acidic sugars, including uronic acids and sialic acids, are also important components in some complex carbohydrates.
View Article and Find Full Text PDFAnionic polysaccharides, such as glycosaminoglycans (GAGs) and alginate, readily undergo source-induced fragmentation when analyzed by electrospray mass spectrometry with the use of high source cone voltage. The dissociation chemistry converts all components of a polysaccharide into a small set of structurally characteristic small saccharides. This chemistry enables the collective detection of a polysaccharide through the detection of one or more small saccharides.
View Article and Find Full Text PDFThis article addresses the identification and quantification of the chemical species resulting in resonances at 2.17 and 2.25 ppm in the (1)H nuclear magnetic resonance (NMR) spectrum of pharmaceutical-grade heparin sodium.
View Article and Find Full Text PDFPertussis toxoid, an acellular pertussis vaccine prepared by hydrogen peroxide treatment in the presence of Fe(3+), has not been well characterized. Because the toxoid has been a part of the DTaP vaccine for infants, it is of interest and significance to have a clear understanding of its structure. The five subunits of pertussis toxin (PT) have a combined molecular weight of approximately 95,000Da.
View Article and Find Full Text PDFFrom late December 2007 to February 2008, the number of adverse responses to heparin infusions rose noticeably above baseline levels in North America, ultimately resulting in a widespread recall of all heparin vial products made by Baxter Healthcare. Using various analytical techniques and the de novo synthesis of a fully sulfated chondroitin sulfate (FSCS) derivative, the authors have confirmed the identity of the contaminant as an oversulfated chondroitin sulfate (OSCS) and have also defined the heterogeneity and concentration of this contaminant in various lots of heparin. Using both contaminated heparin products and the synthetically produced derivative, the authors have shown that the OSCS produces a dose-dependent hypotension in both pigs and rats and that the response in rats can be abrogated with bradyzide, a rodent-selective B(2) bradykinin receptor antagonist.
View Article and Find Full Text PDFSulfated glycosaminoglycans (GAGs) are difficult molecules for analysis by mass spectrometry due to their complexity in saccharide composition, polydispersity, and sequence heterogeneity. Structural information is typically derived from their enzymatic or chemical digests. Many analytical studies focused on the determination of disaccharide compositions.
View Article and Find Full Text PDFLiquid chromatography-mass spectrometry (LC-MS) with a dual spray electrospray ionization source has been used to measure the molecular weights of pertussis toxin (PT) subunits. Measurement accuracy better than 0.4 Da was achieved for all PT subunits in the molecular weight range of 11,000 to 27,000 Da.
View Article and Find Full Text PDFGenes Chromosomes Cancer
May 2002
Genetic alterations serve as beacons for the involvement of specific pathways in tumorigenesis. It was previously shown that 5% of prostate tumors harbor CTNNB1 mutations, suggesting that this tumor type may involve a deregulated APC/CTNNB1 pathway. To explore this possibility further, we searched for mutations in genes implicated in this pathway in 22 samples that included cell lines, xenografts, and primary tumors.
View Article and Find Full Text PDFSeveral aminocyclitol-aminoglycoside antibiotics have been studied by tandem mass spectrometry. Glycosidic bond cleavages were the major reactions in the low energy collisionally activated decomposition (CAD) of the protonated antibiotics. Only the glycoside residing on the C6-O of the 2-deoxystreptamine was observed to undergo significant decomposition at the C2-C3 and O-C1 bonds.
View Article and Find Full Text PDFAlkylation of tryptophan occurred during the synthesis of a 19-amino acid peptide of the following sequence: Tyr Ala Ala Gln Asn Arg Arg Gly Leu Asp Leu Leu Phe Trp Glu Gln Gly Gly Leu. Alkylation was found to occur during cleavage of the peptide from the solid support under acidic conditions in the presence of Tmob, which is used for protecting glutamine and asparagine. Presence of alkylated tryptophan was confirmed by mass spectrometry, HPLC and amino acid sequence analyses.
View Article and Find Full Text PDFBiomed Environ Mass Spectrom
October 1990
Several aminophenanthrenes have been examined with electron impact mass spectrometry. The trifluoroacetic anhydride (TFAA) and perfluoropropionic anhydride (PFPA) derivatives of 4-aminophenanthrene have been studied with electron impact as well as both positive and negative ion chemical ionization mass spectrometry utilizing methane as a reagent gas. The resulting mass spectra indicate a loss of water from the derivatives and a mechanism is proposed to account for this loss.
View Article and Find Full Text PDFAmino acids were identified and quantified in the stomach fluid recovered from animals fasted 8, 24, and 48 h. After in vitro chlorination of stomach fluid, three chloramino acids, N-chloroglycine, either N-chloroleucine or N-chloroisoleucine, and N-chlorophenylalanine, were identified by GC/MS analysis of dansylated methyl ester derivatives. Formation of N-chlorovaline and N-chloroserine was suggested by their HPLC retention times, but their identification could not be confirmed by GC/MS data.
View Article and Find Full Text PDFBiomed Environ Mass Spectrom
May 1988
The electron impact (EI) mass spectra of the permethyl, peracetyl and per(trifluoroacetyl) derivatives of hydroxylated benzo[a]pyrene (B[a]P) metabolites were determined and the fragmentation chemistry producing the spectra elucidated. The metabolites investigated were: 3-hydroxy-B[a]P; 7,8-dihydro-7,8-dihydroxy-B[a]P; 7,8,9,10-tetrahydro-7,8,9-trihydroxy-B[a]P; and 7,8,9,10-tetrahydro-7,8,9,10-tetrahydroxy-B[a]P. In addition, the positive and negative methane chemical ionization spectra were determined for the derivatives of the BP-tetrol.
View Article and Find Full Text PDFAn 800-850 degrees F solvent-refined coal-II liquid was fractionated into chemical classes to obtain the aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAH), nitrogen-containing polycyclic aromatic compounds (NPAC), and hydroxy-substituted PAH (hydroxy-PAH). The isolated NPAC fraction was refractionated by chemical class both before and after undergoing a nitrosation reaction. The nitrosated and non-nitrosated refractionated NPAC fractions were further subfractionated into secondary amine (pyrroles), primary amine-enriched (amino-PAH), and tertiary amine (azaarene) classes.
View Article and Find Full Text PDFJ Toxicol Environ Health
March 1987
Stack-collected fly-ash particles from a commercial pulverized-coal power plant were extracted with 60/40 w/w benzene-methanol to remove as much of the organic fraction as possible. The extract was sequentially fractionated on a series of high-performance liquid chromatography columns, and the Salmonella bacterial mutagenicity assay using both normal and nitroreductase-deficient strains was used to localize the most mutagenic fractions. Selected fractions were analyzed by a variety of techniques, including gas chromatography with dual-flame ionization and thermionic nitrogen-phosphorus detectors, gas chromatography-mass spectrometry, direct-probe low-resolution or low-voltage mass spectrometry, and high-resolution mass spectrometry.
View Article and Find Full Text PDFBioelectromagnetics
September 1986
Rats exposed for 3 weeks to uniform 60-Hz electric fields of 39 kV/m (effective field strength) failed to show normal pineal gland circadian rhythms in serotonin N-acetyl transferase activity and melatonin concentrations. The time required for recovery of the melatonin rhythm after cessation of field exposure was determined to be less than 3 days. The rapid recovery suggests that the overall metabolic competence of the pineal is not permanently compromised by electric-field exposure, and that the circadian rhythm effect may be neuronally mediated.
View Article and Find Full Text PDFNarrow temperature range distillates from biologically active solvent refined coal-I and -II heavy-end coal liquids were fractionated according to chemical class and assayed for initiation of skin carcinogenesis in CD-1 mice. In addition, instrumental chemical analyses were performed on the distillates and their chemical fractions. Results showed that initiation activity in these complex fuel mixtures could be segregated both by boiling point and chemical class.
View Article and Find Full Text PDFStack-collected coal fly ash from western low-sulfur coal was extracted with 60:40 benzene/methanol. This extract was fractionated by preparative-scale high performance liquid chromatography (HPLC) and the mutagenic activity of 14 fractions was evaluated by microbial assay with Salmonella typhimurium TA1538. A widespread distribution of direct-acting mutagens, which probably includes both mono- and dinitroaromatics, was detected.
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