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A new polymeric (methyl methacrylate/ethylene glycol dimethacrylate/1,2-epoxy-5-hexene) base/matrix has been fabricated and decorated with zwitterionic hydrophilic cysteic acid (Cya) for the enrichment of intact N-glycopeptides from standards and biological samples. Terpolymer-Cya provides good enrichment efficiency, improved hydrophilicity, and selectivity by virtue of better surface area (2.09 × 102 m2/g) provided by terpolymer and the zwitterionic property offered by cysteic acid. Cysteic acid-functionalized polymeric hydrophilic interaction liquid chromatography (HILIC) sorbent enriches 35 and 24 N-linked glycopeptides via SPE (solid phase extraction) mode from tryptic digests of model glycoproteins, i.e., immunoglobulin G (IgG) and horseradish peroxidase (HRP), respectively. Zwitterionic chemistry of cysteine helps in achieving higher selectivity with BSA digest (1:200), and lower detection limit down to 100 attomoles with a complete glycosylation profile of each standard digest. The recovery of 81% and good reproducibility define the application of terpolymer-Cya for complex samples like a serum. Analysis of human serum provides a profile of 807 intact N-linked glycopeptides via nano-liquid chromatography-tandem mass spectrometry (nLC-MS/MS). To the best of our knowledge, this is the highest number of glycopeptides enriched by any HILIC sorbent. Selected glycoproteins are evaluated in link to various cancers including the breast, lung, uterine, and melanoma using single-nucleotide variances (BioMuta). This study represents the complete idea of using an in-house developed strategy as a successful tool to help analyze, relate, and answer glycoprotein-based clinical issues regarding cancers. [ABSTRACT FROM AUTHOR]

Here, we investigated the effect of dietary cysteic acid on the growth performance, sulfur amino acid content, and gene expression levels of taurine-synthesizing enzymes, growth hormone (GH), and insulin-like growth factor 1 (IGF-1) in Japanese flounder Paralichthys olivaceus. Juvenile flounder (0.9 g) were fed one of four diets for 30 days: with 0.25, 0.5, or 1.0% cysteic acid (C0.25, C0.5, C1.0) supplementation and without supplementation (control). Fish in the C0.25 and C0.5 groups showed significantly better growth than those in the control group (P < 0.05). Body taurine content was significantly higher in C0.25, C0.5, and C1.0 fish than in control fish (P < 0.05). Although there was no significant difference in gene expression levels of taurine-synthesizing enzymes and GH among groups (P > 0.05), the expression level of IGF-1 in C1.0 fish was significantly higher than that in controls (P < 0.05). Our results suggest that Japanese flounder can synthesize taurine from cysteic acid, that dietary supplementation with up to 0.5% cysteic acid promotes fish growth, and that dietary cysteic acid can affect the GH-IGF axis in Japanese flounder. These findings thus highlight the importance of the cysteic acid pathway for taurine synthesis and growth in this species. [ABSTRACT FROM AUTHOR]

A study of the effect of a seasonal decrease in ambient temperature on the composition of free amino acids and ninhydrin-positive secondary metabolites in gastrocnemius muscles of the frog Rana temporaria revealed that at the onset of winter anabiosis, as compared to the summer season, the alanine pool increased from 2.43 to 6.10 µmol/g w.w., and the 3-methylhistidine pool rose from 1.52 to 2.80 µmol/g w.w. For the first time, muscles of poikilothermic animals (namely, frogs) were found to contain cysteic acid and phosphoethanolamine, the level of which increased by the onset of hibernation, particularly for cysteic acid (from 0.91 to 2.15 µmol/g w.w.). The taurine level proved to be far lower compared to animals both of lower and higher phylogenetic ranks, but by the onset of hibernation it increased almost threefold. Presumably, the accumulation of the above metabolites relates to their protective role at temperatures that are extremely low for the survival of R. temporaria. [ABSTRACT FROM AUTHOR]

This study reports results of kinetic and mechanistic studies on the reactions of aquacobalamin (H2OCbl+) with oxo-derivatives of cysteine, that is, cysteinesulfinic and cysteic acids, hypotaurine and taurine. The reactions with cysteinesulfinic acid and hypotaurine result in formation of S-bound complexes, whereas cysteic acid and taurine are coordinated with aquacobalamin via amino-group. Reaction of taurine with H2OCbl+ produces a substantially more stable complex than with cysteic acid, whereas the affinity of cysteinesulfinic acid toward aquacobalamin is slightly higher than that of hypotaurine. [ABSTRACT FROM AUTHOR]

Taurine and hypotaurine are abundantly present in molluskan tissues; however, the pathways for their biosynthesis have not yet been well investigated. In this study, we established a method for simultaneous detection of taurine-related compounds, including taurine, hypotaurine, cysteic acid, cysteine sulfinic acid (CSA), cystathionine, γ-aminobutyric acid, and β-alanine along with 17 free amino acids, using phenylthiocarbamyl derivatization in ammonia-containing solution, followed by injection into reversed-phase high-performance liquid chromatography. Using this method, we analyzed the major tissues (gill, mantle, adductor muscle, foot, and digestive gland) of the hydrothermal-vent-specific mussel Bathymodiolus septemdierum. The gill and digestive gland were suggested to be the major organs for taurine/hypotaurine biosynthesis because taurine and hypotaurine levels tended to be high, and their precursors, i.e., cysteine, cysteic acid, and CSA (only in digestive gland), were detected in these two tissues. Cystathionine was detected at relatively high level in digestive gland and in other tissues at low levels, suggesting its role as storage material for taurine/hypotaurine biosynthesis. Adductor muscle was found to be rich in free amino acids, mainly due to abundance of non-sulfur-containing amino acids. [ABSTRACT FROM AUTHOR]

Using infrared and Raman microspectroscopy, the authors examined the interaction of cold atmospheric plasma with the skin's built-in protective cushion, the outermost skin layer stratum corneum. Following a spectroscopic analysis, the authors could identify four prominent chemical alterations caused by plasma treatment: (1) oxidation of disulfide bonds in keratin leading to a generation of cysteic acid; (2) formation of organic nitrates as well as (3) of new carbonyl groups like ketones, aldehydes and acids; and (4) reduction of double bonds in the lipid matter lanolin, which resembles human sebum. The authors suggest that these generated acidic and NO-containing functional groups are the source of an antibacterial and regenerative environment at the treatment location of the stratum corneum. Based upon the author's results, the authors propose a mechanistic view of how cold atmospheric plasmas could modulate the skin chemistry to produce positive long-term effects on wound healing: briefly, cold atmospheric plasmas have the potential to transform the skin itself into a therapeutic resource. [ABSTRACT FROM AUTHOR]

Berberine (BBR), one of the major constituents of Chinese herb Rhizoma coptidis, has been reported to exert beneficial effects to various diseases, including Alzheimer's disease (AD). In the present work, we aimed to investigate the effects of BBR on neuronal cell death induced by homocysteic acid (HCA), which was considered as a risk of AD. BBR significantly reduced HCA-induced reactive oxygen species (ROS) generation, lactate dehydrogenase release and subsequent cell death. LY294002, the PI3K inhibitor, blocked the protection as well as the up-regulation of Akt phosphorylation of BBR. Taken together, our results indicate that BBR protects HCA-induced HT-22 cell death partly via modulating Akt pathway, suggesting BBR may be a promising therapeutic agent for the treatment of HCA-related diseases, including AD. [ABSTRACT FROM AUTHOR]

Ovarian cancer (OVC) is one of the most difficult types of cancer to detect in the early stages of its development. There have been numerous attempts to identify a biomarker for OVC; however, an accurate diagnostic marker has yet to be identified. The present study profiled OVC candidate metabolites from the serum to identify potential diagnostic markers for OVC. Data regarding low-mass ions (LMIs) in the serum were obtained using matrix-assisted laser desorption/ionization (MALDI)-time-of-flight analysis. MALDI-mass spectrometry (MS) analysis of each serum sample was repeated six times in order to reduce the likelihood of experimental errors. The intensity of the LMI mass peaks were normalized using total peak area sums. The normalized intensity of LMI was used in principal component analysis-discriminant analysis to differentiate between 142 patients with OVC and 100 healthy control participants. Liquid chromatography-MS/MS was used to identify the selected LMIs. Extracted ion chromatogram analysis was used to measure the relative quantity of candidate metabolites from the LMI mass peak areas. The concentration of common metabolites in the serum was determined using ELISA. The top 20 LMI mass peaks with a weigh factor over 0.05 were selected to distinguish between the patients with OVC and the controls. Among the LMIs, two with 184.05 and 496.30 m/z were identified as L-homocysteic acid (HCA) and lysophosphatidylcholine (LPC) (16:0), respectively. The relative quantity of LPC (16:0) was found to be decreased in the OVC serum (P=0.05), while the quantity of HCA was observed to be significantly higher in the OVC serum (P<0.001). HCA was not detected in 59 cases out of the 63 control participants; however, the majority of the cases of OVC (16/25) exhibited significantly higher quantities of HCA. When the cutoff was 10 nmol/ml, the sensitivity and specificity of HCA were 64.0 and 96.9%, respectively. The level of LPC (16:0) was significantly correlated with tumor grade (P=0.045). HCA and LPC (16:0) showed correlation with stage and tumor histology, but the limited sample size resulted in a lack of statistical significance. The findings of the present study suggest that HCA may have potential to be a biomarker for OVC. T he stratified screening including LPC (16:0) did not significantly increase the power for OVC screening; however, the present study showed that profiling LMIs in serum may be useful for identifying candidate metabolites for OVC screening. [ABSTRACT FROM AUTHOR]

The aim of this manuscript is to develop a combined method for the detection and elimination of oxalic acid (OA) in aqueous environment. For that, the surface of glassy carbon (GC) electrode has been modified by oxidation of L-cysteine using cyclic voltammetric (CV) technique. After modification, the formation of a compact and uniform cysteic acid layer film was achieved and it was confirmed by surface analysis (scanning electron microscopy (SEM) and atomic force microscopy (AFM)). Estimation of the linear range, calibration function and limit of detection for OA were performed by differential pulse voltammetry using Cysteine-modified electrode (Cysteine-MGC). Due to its stability and sensitive response to OA, it was used for monitoring OA during its electrochemical oxidation at Ti/Pt anode. DPV analyses have been compared with classic titration method and HPLC achieving a good fit, confidence intervals and limits. The results are described and discussed in the light of the existing literature. [ABSTRACT FROM AUTHOR]

We have isolated a minor soluble green-colored heme protein (GHP) from the purple sulfur bacterium, Halochromatium salexigens, which contains a c-type heme. A similar protein has also been observed in the purple bacteria Allochromatium vinosum and Rhodopseudomonas cryptolactis. This protein has wavelength maxima at 355, 420, and 540 nm and remains unchanged upon addition of sodium dithionite or potassium ferricyanide, indicating either an unusually low or high redox potential, respectively. The amino-acid sequence indicates one heme per peptide chain of 72 residues and reveals weak similarity to the class I cytochromes. The usual sixth heme ligand methionine in these proteins appears to be replaced by a cysteine in GHP. Only one known cytochrome has a cysteine sixth ligand, SoxA (cytochrome c-551) from thiosulfate-oxidizing bacteria, which is low-spin and has a high redox potential because of an un-ionized ligand. The native size of GHP is 34 kDa, its subunit size is 11 kDa, and the net charge is −12, accounting for its very acidic nature. A database search of complete genome sequences reveals six homologs, all hypothetical proteins, from Oceanospirillum sp., Magnetococcus sp., Thiobacillus denitrificans, Dechloromonas aromatica, Thiomicrospira crunogena and Methylobium petroleophilum, with sequence identities of 35–64%. The genetic context is different for each species, although the gene for GHP is transcriptionally linked to several other genes in three out of the six species. These genes, coding for an RNAse, a protease/chaperone, a GTPase, and pterin-4a-carbinolamine dehydratase, appear to be functionally related to stress response and are linked in at least 10 species. [ABSTRACT FROM AUTHOR]

S-Nitrosocompounds are formed when aqueous solutions of cysteine or glutathione are exposed to ultrasound (880 kHz) in air. The yield of the S-nitrosocompounds was as high as 10% for glutathione and 4% for cysteine of the initial thiol concentrations (from 0.1 to 10 mM) in the aqueous solutions. In addition to the formation of S-nitrosocompounds, thiol oxidation to disulfide forms was observed. After the oxidation of over 70% of the sulfhydryl groups, formation of peroxide compounds as well as cysteic acid derivatives was recorded. The formation of the peroxide compounds and peroxide radicals in the ultrasound field reduced the yield of S-nitrosocompounds. S-Nitrosocompounds were not formed when exposing low-molecular-weight thiols to ultrasound in atmospheres of N2 or CO. In neutral solutions, ultrasound-exposed cysteine or glutathione released NO due to spontaneous degradation of the S-nitrosocompounds. N2O3, produced due to the spontaneous degradation of the S-nitrosocompounds in air, nitrosylated sulfhydryl groups of glutathione manifested in the appearance of new absorption bands at 330 and 540 nm. The nitrogen compounds formed in an ultrasound field modified the sulfhydryl groups of apohemoglobin and serum albumin. The main target for ultrasound-generated oxygen free radicals were cystine residues oxidized to cysteic acid residues. [ABSTRACT FROM AUTHOR]

Samples of hair from five different female Caucasians were selected, while attempting to eliminate or minimize variables introduced by factors, suggested in previous literature, related to genetics, malnutrition, and cosmetic alteration, to analyze for 18 amino acids. The objective was to determine if human hair from such a similarly sampled group differs in composition from individual to individual. Significant differences were found for 9 of the 18 amino acids analyzed at the α = 0.01 level, however, the percent deviations for 16 of the amino acids were within ± 6%. Comparison of these samples of hair with pooled dark brown hair, from female Causasians, and purchased from a hair dealer, indicated a note-worthy difference only in the cystine content. Comparison of these data from human hair with that from 64's Merino wool indicates substantial differences between cystine, glycine, tyrosine, and phenylalanine. Statistically significant differences were suggested for other amino acids between Merino wool and human hair; however, the magnitude of the numerical differences, in these instances, was substantially lower than for the above mentioned four amino acids. Weathering effects in human hair were also explored, suggesting degradation to the amino acid residues of cystine, tyrosine, hysine, and histedine by the elements. [ABSTRACT FROM PUBLISHER]

An account is given of an investigation in which ampholytes of suint from degreased Australian merino wool were isolated by ion-exchange chromatography and the free amino acids were separated from the peptides by chromatography on Sephadex impregnated with cupric ions. Suint contains 21 free amino acids, of which nineteen have been identified. Possible sources of free amino acids are considered; they are probably ovine metabolic products, but there is some evidence to suggest bacterial contamination. [ABSTRACT FROM AUTHOR]

An account is given of an investigation in which, in connexion with a study of canary staining, samples of suint from a white merino, a white Romney, and a yellow-banded Romney wool were analysed and bicarbonate-carbonate was detected in each, the largest amount (8-4% as potassium carbonate on the dry weight) occurring in suint from the canary-stained band. In other respects, there was little difference between the suints from white and yellow wools. The staining of wool by several simple aldehydes and similar substances is briefly reported. [ABSTRACT FROM AUTHOR]

4H-chromenes play a significant role in natural and pharmacological products. Despite continuous advances in the synthesis methodology of these compounds, there is still a lack of a green and efficient method. In this study, we have designed cysteic acid chemically attached to magnetic graphene oxide (MNPs·GO-CysA) as an efficient and reusable solid acid catalyst to synthesize 4H-chromene skeletons via a one-pot three components reaction of an enolizable compound, malononitrile, an aldehyde or isatin, and a mixture of water–ethanol as a green solvent. This new heterogeneous catalyst provides desired products with a good to excellent yield, short time, and mild condition. This procedure presents an environmentally friendly approach for the synthesis of a great number of 4H-chromene derivatives. [ABSTRACT FROM AUTHOR]

The reducing and capping sites along with their local structure impact photo properties of the red bovine serum albumin-capped Au nanocluster (BSA-AuNC), however, they are hard to identify. We developped a workflow and relevant techniques using mass spectrometry (MS) to identify the reducing and capping sites of BSA-AuNCs involved in their formation and fluorescence. Digestion without disulfide cleavages yielded an Au core fraction exhibiting red fluorescence and [AunSm] ion signals and a non-core fraction exhibiting neither of them. The core fraction was identified to mainly be comprised of peptides containing cysteine residues. The fluorescence and [AunSm] signals were quenched by tris(2-carboxyethyl)phosphine, confirming that disulfide groups were required for nanocluster stabilization and fluorescence. By MS sequencing, the disulfide pairs, C75–C91/C90–C101 in domain IA, C315–C360/C359–C368 in domain IIB, and C513–C558/C557–C566 in domain IIIB, were identified to be main capping sites of red AuNCs. Peptides containing oxidized cysteines (sulfinic or cysteic acid) were identified as reducing sites mainly in the non-core fraction, suggesting that disulfide cleavages by oxidization and conformational changes contributed to the subsequent growth of nanoclusters at nearby intact disulfide pairs. This is the first report on precise identification of the reducing and capping sites of BSA-AuNCs. [ABSTRACT FROM AUTHOR]

The dynamics of specimen trafficking and testing patterns can inform fundamental laboratory management practices. The objective of this study was to employ a dashboard designed for data analysis and visualization to understand clinical laboratory utilization at a single institution that processes 12 million specimens, admits 48,000 patients, and serves nearly 1.5 million outpatient visits annually. Architecturally, an analytics server queries the laboratory information system (LIS) at 24-hour intervals and populates a database with operational information. The analytical server then supports a customized dashboard offering daily and aggregate operational metrics covering three years of clinical laboratory information. The LIS design is otherwise archetypal and communicates bidirectionally with the electronic medical record system and laboratory instrumentation middleware. The dashboard was queried to reveal important metrics, such as traffic peaks, distribution of sample accession volumes, test turnaround time, and credit/cancel/refusal metrics, with location-level and test-level granularity. A very different pattern in sample accessioning flux was observed for inpatient and outpatient workloads. A single large daily peak for inpatient sample traffic occurs at 6:30 AM, representing approximately 580 samples accessioned between 6:00 and 7:00 AM. Conversely, a bimodal traffic peak for outpatient samples occurs at 2:30 PM and 8:30 PM with approximately 470 samples and 460 samples accessioned during each peak time, respectively. This information allows us to reliably quantify, illustrate, and predict the impact of inpatient phlebotomy collection and outpatient sample delivery workflows on the clinical laboratory. Such data can directly inform staffing decisions, reagent procurement, instrumentation needs, quality control practices, and other laboratory management responsibilities. This model is relevant especially to high volume laboratories with automated accessioning systems. [ABSTRACT FROM AUTHOR]

In the quantitative analysis of cystine and cysteine, before hydrolysis the compounds are often oxidized to cysteic acid with performic acid. The applicability of this process to the quantification of the enantiomers of cystine and cysteine has been examined. An RPHPLC analytical method was developed for determination of the amount of cysteic acid enantiomers and the rate of conversion during oxidation from cystine and cysteine into cysteic acid was determined. Racemization of L-cysteine was not significant during oxidation with performic acid and the process can, therefore, be applied before hydrolysis during quantification of enantiomers of these compounds. [ABSTRACT FROM AUTHOR]