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Journal articles on the topic 'Mass spectometry'

Author: Grafiati

Published: 4 June 2021

Last updated: 20 February 2023

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1

Santos, Lúcia, Jorge Barbosa, M. Conceição Castilho, Fernando Ramos, Carlos A. Fontes Ribeiro, and M. Irene Noronha da Silveira. "Determination of chloramphenicol residues in rainbow trouts by gas chromatography–mass spectometry and liquid chromatography–tandem mass spectometry." Analytica Chimica Acta 529, no. 1-2 (January 2005): 249–56. http://dx.doi.org/10.1016/j.aca.2004.07.017.

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2

Valentine, Stephen J., Xiaoyun Liu, Manolo D. Plasencia, Amy E. Hilderbrand, Ruwan T. Kurulugama, Stormy L. Koeniger, and David E. Clemmer. "Developing liquid chromatography ion mobility mass spectometry techniques." Expert Review of Proteomics 2, no. 4 (August 2005): 553–65. http://dx.doi.org/10.1586/14789450.2.4.553.

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3

Schweikhard, Lutz. "Excitation and detection geometries for Fourier-transform mass spectometry." Rapid Communications in Mass Spectrometry 8, no. 1 (January 1994): 10–13. http://dx.doi.org/10.1002/rcm.1290080103.

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4

Crighton, Jim. "Inductively coupled and microwave induced plasma sources for mass spectometry." TrAC Trends in Analytical Chemistry 15, no. 7 (August 1996): X. http://dx.doi.org/10.1016/0165-9936(96)83728-9.

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5

Chace, Donald H., Roser Pons, Claudia A. Chiriboga, Donald J. McMahon, Ingrid Tein, Edwin W. Naylor, and Darryl C. De Vivo. "Neonatal Blood Carnitine Concentrations: Normative Data by Electrospray Tandem Mass Spectometry." Pediatric Research 53, no. 5 (May 2003): 823–29. http://dx.doi.org/10.1203/01.pdr.0000059220.39578.3d.

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6

Wilson, Stephen R., and Yunhui Wu. "Selective alkali metal binding of valinomycin by electrospray ionization mass spectometry." Supramolecular Chemistry 3, no. 4 (July 1994): 273–77. http://dx.doi.org/10.1080/10610279408034926.

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7

Křen, Vladimír, and Tomáš Řezanka. "Sterols and fatty acids in Peziza muralis." Canadian Journal of Microbiology 42, no. 11 (November 1, 1996): 1176–78. http://dx.doi.org/10.1139/m96-150.

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Composition of sterols and fatty acids in fruiting bodies of fungus Peziza muralis were determined by gas chromatography – mass spectometry. Sterol distribution (e.g., brassicasterol occurrence) confirms phylogenetic relations to the order Tuberales. Nontypical lipid composition reflects extreme conditions (e.g., sunny, dry, and mineral-rich niches) where this fungus occurs.Key words: Peziza muralis, lipids, sterols, brassicasterol, fatty acids.

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8

KADOWAKI, Satoshi, and Hirotaka NAITOH. "Determination of ethylthiometon residues in environmental samples by gas chromatography/mass spectometry." Journal of Environmental Chemistry 3, no. 4 (1993): 747–59. http://dx.doi.org/10.5985/jec.3.747.

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9

Hallégot, P., C. Girod, M. M. Le Beau, and R. Levi-Setti. "Direct nucleotide mapping of human chromosomes by imaging Secondary Ion Mass Spectometry." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 3 (August 12, 1990): 114–15. http://dx.doi.org/10.1017/s042482010015811x.

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The relationship between chromosome banding patterns obtained by a variety of staining methods (G,Q,R, and C) and the actual nucleotide content of the different bands, has been the subject of extensive investigations over the past 20 years and has been critically reviewed. Although a number of in vitro experiments have shown preference of certain stains for specific bases, the presence of proteins in chromosomes and their interaction with the DNA, has to some extent obscured a direct correlation between banding patterns and base content. Even the widely useful differential staining following substitution of the thymidine in DNA by the analog bromodeoxyuridine (BrdU), is not independent of the presence of proteins. Clearly, it would be desirable to examine physical methods capable of assessing DNA base composition in chromosomes, free of chemical interactions. One of these methods, already successfully applied involves the 3H-labelling of nucleotides and subsequent detection by autoradiography. An alternative approach, the subject of this report, is capable of attaining much improved spatial resolution and consists of the detection of isotope-labelled nucleotides by secondary ion mass spectrometry (SIMS).

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10

Schwartz, Brenda L., Alan L. Rockwood, Richard D. Smith, Donald A. Tomalia, and Ralph Spindler. "Detection of high molecular weight starburst dendrimers by electrospray ionization mass spectometry." Rapid Communications in Mass Spectrometry 9, no. 15 (1995): 1552–55. http://dx.doi.org/10.1002/rcm.1290091516.

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11

Guntarti, Any, Ibnu Gholib Gandjar, and Nadia Miftahul Jannah. "Authentication of Wistar rat fats with gas chromatography mass spectometry combined by chemometrics." Potravinarstvo Slovak Journal of Food Sciences 14 (January 28, 2020): 52–57. http://dx.doi.org/10.5219/1229.

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Indonesia is a country with the largest Muslim population in the world, which is very concerned about halal food. The most problem that’s very concerning nowadays was that food products were contaminated by unclean meat, such as rat meat. The purpose of this study was to authenticate rat fat using Gas Chromatography-Mass Spectrophotometry (GC-MS) combined with chemometrics. In this study, rat fat were heated in oven at 90 °C – 100 °C for approximately one hour until the oil came out. After that, the derivatization process was carried out to convert fat into methyl ester compounds using NaOCH3 and BF3. Methyl ester compound than injected into the GCMS instrument system. In addition to rat fat, other fat extraction were carried out, such as pigs, cows, chickens, wild boars, dogs, and goats. The combination of chemometrics Principal Component Analysis (PCA) was used to classify rat fat with other animal fat. Based on the results of the study showed that fatty acids in rats using GCMS produced 6 types of fatty acids, namely: myristat (0.15 ±0.09%), palmitoleate (0.73 ±0.54%), palmitate (19.08 ±3.54%), linoleate (30.14 ±16.90%), oleate (40.48 ±2.74%), and stearate (2.55 ±0.01%). Total content of rat fatty acids was 93.13%, with unsaturated fatty acids 71.35% and saturated fatty acids 21.78%. Chemometrics PCA from rat fat can be grouped with other animal fats

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12

Kim, H. Y., J. A. Yergey, and N. Salem. "Determination of eicosanoids, phospholipids and related compounds by thermospray liquid chromatography-mass spectometry." Journal of Chromatography A 394, no. 1 (January 1987): 155–70. http://dx.doi.org/10.1016/s0021-9673(01)94169-x.

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13

Van Roy, Wim, Herbert Struyf, Luc Van Vaeck, Renaat Gijbels, and Pablo Caravatti. "Desorption—ionization of organic compounds studied by Fourier-transform laser microprobe mass spectometry." Rapid Communications in Mass Spectrometry 8, no. 1 (January 1994): 40–45. http://dx.doi.org/10.1002/rcm.1290080108.

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14

Mo, Hin-Wai, Daichi Shirakura, Kentaro Harada, Kiyoshi Ishibashi, Takahiro Shibamori, Takashi Miyamoto, and Chihaya Adachi. "3‐2: Analyzing the Degradation Process of Quantum‐Dot LEDs (QLEDs) by Mass Spectometry." SID Symposium Digest of Technical Papers 53, no. 1 (June 2022): 1–4. http://dx.doi.org/10.1002/sdtp.15815.

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15

Kiehntopf, Michael, Diana Schmerler, Frank Martin Brunkhorst, Robert Winkler, Katrin Ludewig, Dirk Osterloh, Frank Bloos, Konrad Reinhart, and Thomas Deufel. "Mass Spectometry-Based Protein Patterns in the Diagnosis of Sepsis/Systemic Inflammatory Response Syndrome." Shock 36, no. 6 (December 2011): 560–69. http://dx.doi.org/10.1097/shk.0b013e318237ea7c.

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16

Dunayevskiy, Y. M., P. Vouros, E. A. Wintner, G. W. Shipps, T. Carell, and J. Rebek. "Application of capillary electrophoresis-electrospray ionization mass spectometry in the determination of molecular diversity." Proceedings of the National Academy of Sciences 93, no. 12 (June 11, 1996): 6152–57. http://dx.doi.org/10.1073/pnas.93.12.6152.

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17

Kobayashi, H., K. Ohyama, N. Tomiyama, Y. Jimbo, O. Matano, and S. Goto. "Determination of pesticides in river water by gas chromatography—mass spectometry—selected-ion monitoring." Journal of Chromatography A 643, no. 1-2 (July 1993): 197–202. http://dx.doi.org/10.1016/0021-9673(93)80553-k.

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18

Oliver, B. M., F. A. Garner, L. R. Greenwood, and J. A. Abrefah. "High-sensitivity quadrupole mass spectometry system for the determination of hydrogen in irradiated materials." Journal of Nuclear Materials 283-287 (December 2000): 1006–10. http://dx.doi.org/10.1016/s0022-3115(00)00200-2.

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19

Yinon, J., and D. G. Hwang. "Identification of urinary metabolites of 2,4,6-trinitro-toluene in rats by liquid chromatography-mass spectometry." Toxicology Letters 26, no. 2-3 (August 1985): 205–9. http://dx.doi.org/10.1016/0378-4274(85)90168-7.

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20

Nascimento Júnior, J. A. A., E. R. G. Oliveira, A. V. A. Lima, T. D. Silva, M. T. S. Correia, and G. F. Carneiro. "Identification by MALDI-TOF Mass Spectometry and Biofilm Formation of Bacteria Isolated From Mare Uterus." Journal of Equine Veterinary Science 66 (July 2018): 122. http://dx.doi.org/10.1016/j.jevs.2018.05.166.

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21

Thienpont, L. M., P. G. Verhaeghe, K. A. Van Brussel, and A. P. De Leenheer. "Estradiol-17 beta quantified in serum by isotope dilution-gas chromatography-mass spectrometry: reversed-phase C18 high-performance liquid chromatography compared with immuno-affinity chromatography for sample pretreatment." Clinical Chemistry 34, no. 10 (October 1, 1988): 2066–69. http://dx.doi.org/10.1093/clinchem/34.10.2066.

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Abstract Here, isotope dilution-gas chromatography-mass spectometry is used as a reference technique for determining the concentration of estradiol-17 beta in candidate human serum Reference Material. The accuracy of assigned concentrations in biologic materials is not only determined by instrumental performance, it also depends greatly on the selectivity of the procedure for isolating the analyte from the biological matrix, an issue which we consider insufficiently addressed in the literature. We introduced reversed-phase C18 high-performance liquid chromatography as a fractionation procedure in addition to the commonly used solvent extraction and column chromatography on Sephadex LH-20. The validity of this approach as part of a Reference Method for measurement of estradiol-17 beta by isotope dilution-gas chromatography-mass spectrometry was investigated by comparison with immuno-affinity chromatography, which on theoretical grounds is generally considered as highly selective.

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22

Guan, Shenheng, and Alan G. Marshall. "Stored waveform inverse Fourier transform (SWIFT) ion excitation in trapped-ion mass spectometry: Theory and applications." International Journal of Mass Spectrometry and Ion Processes 157-158 (December 1996): 5–37. http://dx.doi.org/10.1016/s0168-1176(96)04461-8.

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23

Rajakylá, Eero, Katri Laasasenaho, and Peter J. D. Sakkers. "Determination of mycotoxins in grain by high-performance liquid chromatography and thermospray liquid chromatography—mass spectometry." Journal of Chromatography A 384 (January 1987): 391–402. http://dx.doi.org/10.1016/s0021-9673(01)94686-2.

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24

Gutierrez, Craig, Ilan E. Chemmama, Haibin Mao, Clinton Yu, Ignacia Echeverria, Sarah A. Block, Scott D. Rychnovsky, Ning Zheng, Andrej Sali, and Lan Huang. "Structural dynamics of the human COP9 signalosome revealed by cross-linking mass spectrometry and integrative modeling." Proceedings of the National Academy of Sciences 117, no. 8 (February 7, 2020): 4088–98. http://dx.doi.org/10.1073/pnas.1915542117.

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The COP9 signalosome (CSN) is an evolutionarily conserved eight-subunit (CSN1–8) protein complex that controls protein ubiquitination by deneddylating Cullin-RING E3 ligases (CRLs). The activation and function of CSN hinges on its structural dynamics, which has been challenging to decipher by conventional tools. Here, we have developed a multichemistry cross-linking mass spectrometry approach enabled by three mass spectometry-cleavable cross-linkers to generate highly reliable cross-link data. We applied this approach with integrative structure modeling to determine the interaction and structural dynamics of CSN with the recently discovered ninth subunit, CSN9, in solution. Our results determined the localization of CSN9 binding sites and revealed CSN9-dependent structural changes of CSN. Together with biochemical analysis, we propose a structural model in which CSN9 binding triggers CSN to adopt a configuration that facilitates CSN–CRL interactions, thereby augmenting CSN deneddylase activity. Our integrative structure analysis workflow can be generalized to define in-solution architectures of dynamic protein complexes that remain inaccessible to other approaches.

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25

Dejarme, L. E., S. J. Bauer, R. G. Cooks, F. R. Lauritsen, T. Kotiaho, and T. Graf. "Jet separator/membrane introduction mass spectometry for on-line quantitation of volatile organic compounds in aqueous solutions." Rapid Communications in Mass Spectrometry 7, no. 10 (October 1993): 935–42. http://dx.doi.org/10.1002/rcm.1290071015.

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26

Moreno-Pedraza, Abigail, Laura Valdés-Santiago, Laura Josefina Hernández-Valadez, Alicia Rodríguez-Sixtos Higuera, Robert Winkler, and Dora Linda Guzmán-de Peña. "Reduction of aflatoxin B1 during tortilla production and identification of degradation by-products by direct-injection electrospray mass spectrometry." Salud Pública de México 57, no. 1 (January 7, 2015): 50. http://dx.doi.org/10.21149/spm.v57i1.7402.

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Objective. To determine the effect of pH, and exposure time over the inactivation of aflatoxin B1 (AFB1) during the tortilla making process as well as the degradative molecules generated. Materials and methods. Inactivation of AFB1 in maize-dough with alkaline pH and in alkaline methanolic solutions was determined by HPLC. Kinetics of time exposure of AFB1 in methanolic solution and the degradative products were analyzed by direct injection electrospray mass spectometry (DIESI-MS). Results. The alkaline pH of the maize-dough after nixtamalización between 10.2, and 30-40 minutes of resting at room temperature allows the 100% reduction of AFB1. DIESI-MS analysis of the extracts indicated the presence of two degradation molecules from AFB1.Conclusion. The alkaline pH of maize-dough and resting time are the principal factors involved in diminishing AFB1 levels in tortillas. A procedure to the tortilla making process is proposed, which allows the reduction of remnant AFB1, avoiding the accumulative effect over consumers.

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27

Hao, Xiaofei, and Chengguo Jin. "Nonstoichiometry in KTP and Nb: KTP crystals by high-temperature solutions method." Journal of Nonlinear Optical Physics & Materials 24, no. 04 (December 2015): 1550043. http://dx.doi.org/10.1142/s0218863515500435.

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Nonstoichiometry could cause many point defects and limit the application of KTP crystal. Nonstoichiometry in KTP and Nb:KTP crystals by high-temperature solution method were studied by laser-ablation inductively coupled plasma mass spectometry (LA-ICP-MS) and X-ray photoelectron spectroscopy (XPS). The formation of high potassium and Ti[Formula: see text] centers in KTP and Nb:KTP crystals was analyzed. The effect of niobium on nonstoichiometry in Nb:KTP crystal was discussed. The results showed that high potassium, low phosphate, and low oxygen existed in KTP and Nb:KTP crystal samples. Low phosphate and low oxygen in crystal samples resulted from phosphate volatilization, which could be inhibited by the increase of niobium content. Meanwhile, Ti[Formula: see text] centers in crystal samples were original and formed during crystal growth, and were generated with high potassium simultaneously.

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28

Choi, Sung-Won, Dong-Hoon Bai, Ju-Hyun Yu, and Chul Soo Shin. "Characteristics of the squalene synthase inhibitors produced by a Streptomyces species isolated from soils." Canadian Journal of Microbiology 49, no. 11 (November 1, 2003): 663–68. http://dx.doi.org/10.1139/w03-084.

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Microorganisms producing squalene synthase inhibitors were screened from soils. A high producer was selected and identified as a Streptomyces species. Two active inhibitors were obtained from culture broths via a series of purification processes involving solvent extraction, WK-10 cation-exchange column chromatography, HP-20 adsorption column chromatography, silica-gel column chromatography, preparative HPLC, and crystallization. The inhibitors were confirmed as macrolactins A and F with molecular weights of 402 by UV-absorption spectrometry, fast atom bombardment mass spectometry, and 13C- and 1H-NMR analyses. Kinetic results for macrolactins A and F showed that they appear to be noncompetitive inhibitors of rat liver squalene synthase with IC50 values of 1.66 and 1.53 µmol/L, respectively. Since mammalian squalene synthase was used, these inhibitors have significant potential as therapeutic agents for hyperlipemia and suppression of cholesterol biosynthesis.Key words: squalene synthase inhibitor, Streptomyces species, macrolactins A and F.

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29

Camacho-Luque, Raquel, Alejandro Peña-Monje, Natalia Montiel, Alejandro Barbancho, and Federico García. "Maldi-Tof mass spectometry as a routine technique for identification of typical and atypical mycobacteria in the Laboratory of Clinical Microbiology." ACTUALIDAD MEDICA 100, no. 796 (December 31, 2015): 121–23. http://dx.doi.org/10.15568/am.2015.796.or02.

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30

el May, M. "Evidence of iodine storage within thyroid stroma after iodine treatment: imaging by secondary ion mass spectometry (SIMS) microscopy in goitrous tissue." Journal of Clinical Endocrinology & Metabolism 81, no. 6 (June 1, 1996): 2370–75. http://dx.doi.org/10.1210/jc.81.6.2370.

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31

el May, M., J. Jeusset, A. el May, S. Mtimet, and P. Fragu. "Evidence of iodine storage within thyroid stroma after iodine treatment: imaging by secondary ion mass spectometry (SIMS) microscopy in goitrous tissue." Journal of Clinical Endocrinology & Metabolism 81, no. 6 (June 1996): 2370–75. http://dx.doi.org/10.1210/jcem.81.6.8964879.

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32

Thompson, Patrick M., and James W. Taylor. "A secondary ion mass spectometry study of the desorption mechanisms of F+ from a LiF surface bombarded with Ar+ and Ar2+." Surface Science Letters 176, no. 3 (November 1986): A563. http://dx.doi.org/10.1016/0167-2584(86)91019-4.

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33

Thompson, Patrick M., and James W. Taylor. "A secondary ion mass spectometry study of the desorption mechanisms of F+ from a LiF surface bombarded with Ar+ and Ar2+." Surface Science 176, no. 3 (November 1986): 610–18. http://dx.doi.org/10.1016/0039-6028(86)90059-2.

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34

Cao, Ping, and Mehdi Moini. "Quantitative analysis of fluorimated ethylchloroformate derivatives of non-protein amino acids using positive and negative chemical ionization gas chromatography-mass spectometry." Journal of Chromatography A 710, no. 2 (September 1995): 303–8. http://dx.doi.org/10.1016/0021-9673(95)00476-9.

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35

GÜNTHER, DETLEF, ROLF FRISCHKNECHT, CHRISTOPH A. HEINRICH, and HANS-J. KAHLERT. "Capabilities of an Argon Fluoride 193 nm Excimer Laser for Laser Ablation Inductively Coupled Plasma Mass Spectometry Microanalysis of Geological Materials." J. Anal. At. Spectrom. 12, no. 9 (1997): 939–44. http://dx.doi.org/10.1039/a701423f.

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36

Crosbie, Sarah J., PG Blain, and Faith M. Williams. "Metabolism of n-hexane by rat liver and extrahepatic tissues and the effect of cytochrome P-450 inducers." Human & Experimental Toxicology 16, no. 3 (March 1997): 131–37. http://dx.doi.org/10.1177/096032719701600301.

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1 The in vitro metabolism ofn-hexane was studied in rat liver, lung, brain and skeletal muscle microsomes and in microsomes prepared from cell lines expressing human cytochrome P-450 2E1 or 2B6. The hydro xylated metabolites ofn-hexane were quantified by gas chromatography-mass spectometry. 2 Rat liver and extensor digitorum longus (EDL, fast- twitch skeletal muscle) microsomes and the CYP 2B6 microsomes produced the pre-neurotoxic metabolite of n-hexane, 2-hexanol as a major metabolite in contrast to the other rat tissues examined. 3 Inhibition of 2- and 3-hexanol production from n- hexane by rat lung microsomes using metyrapone, an inhibitor of cytochrome P-450 2B1 activity, resulted in almost complete inhibition of lung microsomal activ ity. 4 Production of all three hexanols was significantly increased with phenobarbital-induced rat liver micro somes, with a 10-fold increase in 2- and 3-hexanol production. A slight increase in 2-hexanol production with phenobarbital-induced rat EDL and brain micro somes was observed. No increase in n-hexane meta bolism was noted following induction with β- naphthoflavone or with ethanol.

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37

Mufrodi, Zahrul, and Shinta Amelia. "Esterification of Glycerol with Acetic Acid in Bioadditive Triacetin with Fe₂O₃/Activated Carbon Catalyst." Key Engineering Materials 849 (June 2020): 125–29. http://dx.doi.org/10.4028/www.scientific.net/kem.849.125.

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Esterification and transesterification processes for biodiesel production generate glycerol which is possible to be converted into triacetin. It is an actractive bioadditive for increasing octane number of fuel. The production of this bioadditive in a biodiesel plant also increases the revenue as raw material comes from biodiesel process production as by-product.This study examines the effects of catalyst concentration and temperature on triacetin production using glycerol from esterification process and acetic acid at volume ratio of 1:3 as raw materials. An activated charcoal as catalyst is activated with sulfuric acid at concentration of 2% and 3% (w/w). The esterification temperatures are varied at 90 and 100°C and the reaction time is set for 3 hours. The samples are taken frequently at certain interval times of 15, 30, and 60 minutes for chemical analysis using Gas Chromatography Mass Spectometry. It is observed that using 2% and 3% (w/w) of catalysts at 90°C and 60 minutes reaction time converts 41.037% and 57.441% of glycerol respectively.

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38

Cid-Uribe, Jimena I., Erika P. Meneses, Cesar V. F. Batista, Ernesto Ortiz, and Lourival D. Possani. "Dissecting Toxicity: The Venom Gland Transcriptome and the Venom Proteome of the Highly Venomous Scorpion Centruroides limpidus (Karsch, 1879)." Toxins 11, no. 5 (April 30, 2019): 247. http://dx.doi.org/10.3390/toxins11050247.

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Venom glands and soluble venom from the Mexican scorpion Centruroides limpidus (Karsch, 1879) were used for transcriptomic and proteomic analyses, respectively. An RNA-seq was performed by high-throughput sequencing with the Illumina platform. Approximately 80 million reads were obtained and assembled into 198,662 putative transcripts, of which 11,058 were annotated by similarity to sequences from available databases. A total of 192 venom-related sequences were identified, including Na+ and K+ channel-acting toxins, enzymes, host defense peptides, and other venom components. The most diverse transcripts were those potentially coding for ion channel-acting toxins, mainly those active on Na+ channels (NaScTx). Sequences corresponding to β- scorpion toxins active of K+ channels (KScTx) and λ-KScTx are here reported for the first time for a scorpion of the genus Centruroides. Mass fingerprint corroborated that NaScTx are the most abundant components in this venom. Liquid chromatography coupled to mass spectometry (LC-MS/MS) allowed the identification of 46 peptides matching sequences encoded in the transcriptome, confirming their expression in the venom. This study corroborates that, in the venom of toxic buthid scorpions, the more abundant and diverse components are ion channel-acting toxins, mainly NaScTx, while they lack the HDP diversity previously demonstrated for the non-buthid scorpions. The highly abundant and diverse antareases explain the pancreatitis observed after envenomation by this species.

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39

Sjåstad, Knut-Endre, Tom Andersen, and Siri Lene Simonsen. "Application of laser ablation inductively coupled plasma multicollector mass spectometry in determination of lead isotope ratios in common glass for forensic purposes." Spectrochimica Acta Part B: Atomic Spectroscopy 89 (November 2013): 84–92. http://dx.doi.org/10.1016/j.sab.2013.08.011.

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40

Escher, Geneviève, Isabelle Vögeli, Robert Escher, Robert C. Tuckey, Sandra Erickson, Zygmunt Krozowski, and Felix J. Frey. "Role of CYP27A1 in progesterone metabolism in vitro and in vivo." American Journal of Physiology-Endocrinology and Metabolism 297, no. 4 (October 2009): E949—E955. http://dx.doi.org/10.1152/ajpendo.00298.2009.

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In the kidney, progesterone is inactivated to 20α-dihydro-progesterone (20α-DH-progesterone) to protect the mineralocorticoid receptor from progesterone excess. In an attempt to clone the enzyme with 20α-hydroxysteroid activity using expression cloning in CHOP cells and a human kidney expression library, serendipitously cDNA encoding CYP27A1 was isolated. Overexpression of CYP27A1 in CHOP cells decreased progesterone conversion to 20α-DH-progesterone in a dose-dependent manner, an effect enhanced by cotransfection with adrenodoxin and adrenodoxin reductase. Incubation of CHOP cells with 27-hydroxycholesterol, a product of CYP27A1, increased the ratio of progesterone to 20α-DH-progesterone in a concentration-dependent manner, indicating that the effect of CYP27A1 overexpression was mediated by 27-hydroxycholesterol. To analyze whether these observations are relevant in vivo, progesterone and 20α-DH-progesterone were measured by gas chromatography-mass spectometry in 24-h urine of CYP27A1 gene knockout (ko) mice and their control wild-type and heterozygote littermates. In CYP27A1 ko mice, urinary progesterone concentrations were decreased, 20α-DH-progesterone increased, and the progesterone-to-20α-DH-progesterone ratio decreased threefold ( P < 0.001). Thus CYP27A1 modulates progesterone concentrations. The underlying mechanism is inhibition of 20α-hydroxysteroid dehydrogenase by 27-hydroxycholesterol.

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41

Betancourt, Francisco, Andràs Kiss, Ivo Krejci, and Tissiana Bortolotto. "ToF-SIMS Analysis of Demineralized Dentin Biomodified with Calcium Phosphate and Collagen Crosslinking: Effect on Marginal Adaptation of Class V Adhesive Restorations." Materials 14, no. 16 (August 12, 2021): 4535. http://dx.doi.org/10.3390/ma14164535.

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This study aimed to assess the effect of biomodification before adhesive procedures on the tooth-restoration interface of class V restorations located in caries-simulated vs. sound dentin, and the quality of dentin surface by time-of-flight secondary ion mass spectrometry (ToF-SIMS). Class V cavities located on cervical dentin were prepared on the buccal surfaces of extracted human molars under the simulation of intratubular fluid flow. Two dentin types, i.e., sound and demineralized by formic-acid, were biomodified with 1% riboflavin and calcium phosphate (CaP) prior to the application of a universal adhesive (Clearfil Universal Bond) in etch and rinse or self-etch mode, and a conventional micro hybrid composite (Clearfil APX). Restorations were subjected to thermo mechanical fatigue test and percentages of continuous margins (% CM) before/after fatigue were compared. Bio modification of dentin surfaces at the molecular level was analyzed by Time-of-Flight Secondary Mass Spectometry (ToF-SIMS). % CM were still significantly higher in tooth-restoration interfaces on sound dentin. Meanwhile, biomodification with riboflavin and CaP had no detrimental effect on adhesion and in carious dentin, it improved the % CM both before and after loading. Etching carious dentin with phosphoric acid provided with the lowest results, leading even to restoration loss. The presence of molecule fragments of riboflavin and CaP were detected by ToF-SIMS, evidencing dentin biomodification. The adhesive interface involving carious dentin could be improved by the use of a collagen crosslinker and CaP prior to adhesive procedures.

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42

Živkov Baloš, Milica, Željko Mihaljev, Sandra Jakšić, Nadežda Prica, Gospava Lazić, Miloš Kapetanov, and Jasna Prodanov Radulović. "INCIDENCE OF HEAVY METALS AND OTHER TOXIC ELEMENTS IN ROE DEER (Capreolus capreolus) TISSUES." Archives of Veterinary Medicine 8, no. 2 (March 8, 2016): 3–10. http://dx.doi.org/10.46784/e-avm.v8i2.109.

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Levels of lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg) and copper (Cu) in the liver, kidney and muscle of 11 individual roe deer (Capreolus capreolus) were determined. Th e samples were prepared by microwave wet digestion. Content of investigated elements was determined by the method of coupled plasma with mass spectometry. The lead concentrations ranged from <0.001 (liver) to 8.455 mg/kg (meat), Cd concentrations ranged from 0.004 (muscle) to 0.818 mg/kg (kidney) and As concentrations ranged from 0.002 (liver) to 0.031 mg/kg (kidney). Concentrations of Hg in examined tissues (liver, kidney, muscle) were under limit of detection (<0.001 mg/kg). Th e concentration of copper in liver ranged from 3.913 to 104.08 mg/kg. Th e results of this study showed that no samples exceeded maximum allowed levels for Cd, Hg, As and Cu. Pb concentrations in muscle samples ranged from 0.008 to 8.455 mg/kg. High concentrations of Pb in two muscle samples are most likely due to the proximity of hunting wound area, as lead was not detected in organ samples. The presence of some elements in the tissues of roe d eer suggests the necessity of further research aimed at identifying the source of contamination in order to preserve the health of both humans and animals.

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Micheluz, A., M. Sulyok, S. Manente, R. Krska, G. C. Varese, and G. Ravagnan. "Fungal secondary metabolite analysis applied to Cultural Heritage: the case of a contaminated library in Venice." World Mycotoxin Journal 9, no. 3 (June 1, 2016): 397–407. http://dx.doi.org/10.3920/wmj2015.1958.

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The secondary metabolite production of several fungal strains of Aspergillus creber, Aspergillus jensenii, Aspergillus penicillioides, Aspergillus protuberus, Aspergillus vitricola, Cladosporium cladosporioides, Eurotium chevalieri, Eurotium halophilicum, Penicillium brevicompactum and Penicillium chrysogenum were characterised by liquid chromatography tamdem mass spectometry. All fungi were isolated from both air and book covers as well as from settled dust from a contaminated library in Venice (Italy). For A. creber and A. jensenii, we identified sterigmatocystin, methoxysterigmatocystin, versicolorin A and related precursors/side metabolites from the biosynthetic pathways. Deoxybrevianamid E, neoechinulin A, pseurotin A and D, and rugulusovin were principally detected from the strains of E. halophilicum, an emerging fungal species implicated in book contaminations in specific indoor niches. The analysis of settled dust showed a wide range of toxic or bioactive fungal metabolites. Forty-five different metabolites were identified in different concentrations; in particular, high amounts of asperglaucide, alamethicin, andrastin A, terrecyclic acid and neoechinulin A were detected. Also one bacterial metabolite, chloramphenicole was detected. This study increases the knowledge about metabolite production of several fungal species, as well as on the indoor presence of fungi that are not detected by aerobiological sampling. These results emphasise how routine dusting operations are necessary and essential in order to prevent further microbiological developments in library environments.

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Liolios, Vasilios, Dimitrios Kanelis, Chrysoula Tananaki, and Maria-Anna Rodopoulou. "A Comparative Study of Healthy and American Foulbrood-Infected Bee Brood (Apis mellifera L.) through the Investigation of Volatile Compounds." Agriculture 12, no. 6 (June 3, 2022): 812. http://dx.doi.org/10.3390/agriculture12060812.

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American Foulbrood (AFB) is a major endemic disease affecting the bee brood and the absence of chemical therapeutic treatments leads beekeepers to develop alternative management plans, based mainly on the prevention and accurate diagnosis of symptoms. One of the main symptoms of the disease is the unpleasant odor caused by the rot of dead larvae. In the present comparative study, we analyzed the odor profile of bee larvae and the presence of characteristic volatile compounds (Gas Chromatography-Mass Spectometry), in an effort to discriminate healthy and AFB-infected brood. A greater number of volatile compounds was identified in the affected brood than the healthy. The presence of (Ε)-β-ocimene was prominent in healthy brood samples in percentages from 85.25 to 99.14%, a compound also detected in all samples of infected brood but in lower percentages (37%). The compounds toluene, xylene, 1,3-dimethylbenzene, 2-nonanone, dimethyl disulfide, and dimethyl trisulfide were detected in 100% of the diseased brood samples, with the latter three being absent from the healthy brood, while 2-undecanone was found in some samples of diseased brood (40.0%). Further investigation of volatile markers may contribute significantly to the successful diagnosis of the disease, aiming at its rapid treatment.

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45

Benchimol, R. E., K. Cooper, Kronberg B.I., and M. Powell. "Reconnaissance study of macrofossils from the upper purus river - Western Amazônia." Acta Amazonica 16 (1986): 327–36. http://dx.doi.org/10.1590/1809-43921986161336.

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Fossils of wood, bone and teeth found along the Upper Purus River οf Amazonia. were studied using conventional microscopy and scanning electron microscopy. Mass spectometry was also used to investigate minor and trace element signatures of bone samples.The microsopy studies showed that there was little alteration of original textures. In the fossil wood samples, identified In thin section as tropical hardwood trees, the replacement of the original material with siderite suggests that fossilization occured in shallow sediments in which interstitial waters were saturated with respect to iron carbenate. In samples of both fossilized bone and wood, precipitation of secondary iron phases was commonly observed in cracks and voids. Other secondary phases Included silica, iron oxides, manganese carbonate. The intimate assοciation οf these secondary phases with the original biological structures could be evidence for a microbiological role in the formation of these phases. The similarity in rare earth element (REE) signatures for 2 fossil bone samples from different modern locations indicates their having shared similar diagenetic histories.The virtually complete preservation of original textures suggests that microscοpic studies could be useful in classifying fossil and even in identifying original materials. Rare carth signatures in fossilized bone may reflect ground water compositions at the time of fossilization.

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Zhu, Wen, Xiao Cheng, Chunhuan Ren, Jiahong Chen, Yan Zhang, Yale Chen, Xiaojiao Jia, et al. "Proteomic characterization and comparison of ram (Ovis aries) and buck (Capra hircus) spermatozoa proteome using a data independent acquisition mass spectometry (DIA-MS) approach." PLOS ONE 15, no. 2 (February 13, 2020): e0228656. http://dx.doi.org/10.1371/journal.pone.0228656.

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47

Marcondes, A. Mario Q., Li Xiang, Brian P. Milless, and H. Joachim Deeg. "Identification of DJ-1/Park-7 as a Determinant of Tnfα-Induced and Stroma-Dependent Apoptosis in Leukemia Using Mass Spectometry and Phosphopetide Analysis." Blood 112, no. 11 (November 16, 2008): 1796. http://dx.doi.org/10.1182/blood.v112.11.1796.1796.

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Abstract The bone marrow microenvironment provides essential signals for the fate of normal hematopoietic and for leukemic cells. Contact with marrow stroma, which is part of the microenvironment, is generally thought to convey anti-apoptotic signals to (clonal) leukemia cells. Patients with low-grade myelodysplastic syndrome (MDS) early in the disease course show high rates of apoptosis in normal and clonal marrow cells, mediated by tumor necrosis factor alpha (TNFα) and other cytokines. As MDS advances and evolves to leukemia, clonal cells tend to become apoptosis resistant. We showed previously that the leukemia-derived cell line KG1a was resistant to TNFα-mediated apoptosis, but TNFα did induce caspase-3 activation and apoptosis in KG1a cells when co-cultured with the human marrow stroma cell line HS5 (derived from healthy marrow). Apoptosis was contact dependent and required expression of TNF receptor 1 on KG1a cells. Identical results were obtained in co-cultures with primary stroma cells. Gene expression profiling of KG1a cells showed that stroma contact resulted in significant upregulation of genes involved in apoptosis, including PYCARD and p53. To further dissect the relevant signaling pathways, we used a PhosphoScan proteomic LC-MS (Liquid chromatography-mass spectrometry) method to identify proteins that were phosphorylated in response to stroma contact. In parallel to KG1a we examined the parent cell line KG1, which is sensitive to TNFα mediated apoptosis. We determined the phosphorylation sites in proteins within the leukemic cell lines using MS2 and MS3 scans. Database searches were performed with X! Tandem and Mascot and results analyzed by PeptideProphet using data from a synthetic doubly-phosphorylated peptide as control. In KG1a cells cultured without stroma support, the peptide DJ-1/Park-7 was highly phosphorylated, and expression of p53 was inhibited as indicated by decreased levels of p53 mRNA and protein. In co-culture with stroma, KG1a cells expressed higher levels of p53 protein, and levels of phosphorylated DJ-1/ Park-7 were undetectable over a time course of 30 min to 24 hours. In apoptosis-sensitive KG1 cells constitutive DJ-1/Park-7 phosphorylation (in the absence of stroma contact) was undetectable, and p53 was expressed at higher levels than in KG1a cells, consistent with the observed activation of caspase-3 and induction of apoptosis in KG1 cells. Taken together, these data suggest that phosphorylation of DJ-1/Park-7, originally identified as an oncogene product involved in cellular transformation, oxidative stress responses, and transcriptional regulation, was associated with repression of p53 and resistance to TNFα-mediated apoptosis. The relevance of DJ-1/Park-7 (and other genes identified by the PhosphoScan proteomic method) in primary MDS cells is currently being investigated at the molecular and functional levels.

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48

Spencer, Andrew, Tiffany Khong, Flora Yuen, Hannah Victoria Giles, Malgorzata Gorniak, Hang Quach, Noemi Horvath, et al. "A Longitudinal Evaluation of Euroflow and Combined Quantitative Immunoprecipitation (QIP) and Free Light Chain (FLC) Mass Spectometry (MS) in Functional High Risk Multiple Myeloma." Blood 134, Supplement_1 (November 13, 2019): 3090. http://dx.doi.org/10.1182/blood-2019-129760.

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Introduction: The achievement of minimal residual disease (MRD) negativity is being increasingly recognised as the optimal measure of therapeutic response for both newly diagnosed and relapsed and/or refractory multiple myeloma (MM) patients. Bone marrow (BM) evaluation with either Next Generation Sequencing (NGS) or Next Generation Flow-cytometry (NGF) affords a high level of sensitivity and the attainment of MRD negativity (< 1 in 10-5 MM cells) with either approach is a powerful predictor of superior progression free survival (PFS). Both, however, are limited by the requirement for invasive bone marrow biopsy and the technical limitations imposed by variability in sample quality. Moreover, we and others have demonstrated the presence of significant spatial heterogeneity in MM that increases in the context of disease progression. Against this background we have evaluated a blood-based strategy for disease burden evaluation, Quantitative ImmunoPrecipitation (Mass Spectometry (QIP MS) and Free Light Chain Mass Spectometry (FLC MS) in a uniformly treated cohort of functional high-risk MM patients also undergoing sequential NGF (EuroFlow platform) MRD evaluation. Methods: Newly diagnosed MM patients failing (<partial remission [PR] as best response) front-line bortezomib-based induction therapy were enrolled onto the Australasian Leukaemia and Lymphoma Group (ALLG) MM17 trial (ACTRN12615000934549) evaluating an intensive salvage approach utilising a combination of carfilzomib, thalidomide and dexamethasone (KTd) as re-induction (KTd x 6 cycles) and as post autologous stem cell transplantation (ASCT) consolidation (KTd x 2 cycles followed by Td x10 cycles). NGF MRD status was determined pre-ASCT, post-ASCT and post-KTd consolidation utilising the standardised 8-colour EuroFlow platform. Matched serum samples from the 3 time-points were evaluated in parallel with QIP and FLC MS. Briefly, polyclonal antibodies (anti-IgG, -IgA, -IgM, -total κ, -total λ, free κ and free λ) covalently attached to paramagnetic microparticles were incubated with serum, washed and treated to simultaneously elute and reduce patient immunoglobulins. Light chain mass spectra were generated on a MALDI-TOF-MS system. Concordance between NGF and MS was assessed via the derivation of Cohen's kappa values. Results: Fifty patients were enrolled onto the ALLG MM17 trial. QIP and/or FLC MS identified the serum monoclonal paraprotein (PP) at baseline in all cases (100% sensitivity). Serum samples for MS with matched BM for NGF were available on 33 patients pre-ASCT, 32 post-ASCT and 26 post-KTd consolidation (91 matched samples in total). Sequential MS demonstrated serological complete remission (disappearance of MS baseline detectable monoclonal intact immunoglobulin [PP] and/or FLC) (CRMS) in 11%, 47% and 53% of patients pre-ASCT, post-ASCT and post-KTd, respectively. NGF MRD negativity at the same time points was 39%, 52% and 71% (the latter equivalent to a 50% MRD negativity rate within the original n=50 intention-to-treat population). The Cohen's kappa values for the 3 time-points were 0.21, 0.18 and 0.35 indicating fair to moderate concordance with the best concordance at the post-KTd consolidation time-point and with a Cohen's kappa value for the entire cohort (n=91) of 0.30. The sequential MS demonstrated that 12 patients had discordant disappearance of baseline PP and free light chains (FLC) prior to achieving CRMS. In 11 the FLC disappeared before the PP and in 1 the PP prior to the FLC. The former though to be due to either the FLC falling below the sensitivity of the technique following successful therapy or the presence of 2 sub-clones with differential drug sensitivity, whereas the latter was likely secondary to the persistence of a FLC expressing sub-clone. Post-KTd MS demonstrated good concordance with serological response (Cohen's kappa value = 0.61) but with 18% of patients demonstrating sCR/CR despite persisting MS detectable PP and/or FLC. Conclusion: These preliminary data confirm the utility of QIP MS and FLC MS for the sequential monitoring of tumour burden in HR MM. Concordance with standard monitoring was good with MS detectable disease in some patients with serological sCR/CR consistent with the higher sensitivity of MS. Concordance with NGF was only fair to moderate mandating the future comparison of larger sample sets to better understand the relationship between the 2 methodologies. Disclosures Spencer: Takeda: Consultancy, Honoraria, Research Funding, Speakers Bureau; Secura Bio: Consultancy, Honoraria; Servier: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; Specialised Therapeutics Australia: Consultancy, Honoraria. Khong:Novartis Oncology: Research Funding. Quach:Janssen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Sanofi: Research Funding; GSK: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees. Kalff:Amgen: Honoraria; Celgene: Honoraria; pfizer: Honoraria. Reynolds:Novartis Australia: Honoraria; Alfred Health: Employment, Other: Biostatistician for trials funded by the Australian government and Abbvie, Amgen, Celgene, GSK, Janssen-Cilag, Merck, Novartis, Takeda, but sponsored by Alfred Health.; AUSTRALASIAN LEUKAEMIA & LYMPHOMA GROUP (ALLG): Consultancy; Novartis AG: Equity Ownership.

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49

Welker, Frido, Mateja Hajdinjak, Sahra Talamo, Klervia Jaouen, Michael Dannemann, Francine David, Michèle Julien, et al. "Palaeoproteomic evidence identifies archaic hominins associated with the Châtelperronian at the Grotte du Renne." Proceedings of the National Academy of Sciences 113, no. 40 (September 16, 2016): 11162–67. http://dx.doi.org/10.1073/pnas.1605834113.

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In Western Europe, the Middle to Upper Paleolithic transition is associated with the disappearance of Neandertals and the spread of anatomically modern humans (AMHs). Current chronological, behavioral, and biological models of this transitional period hinge on the Châtelperronian technocomplex. At the site of the Grotte du Renne, Arcy-sur-Cure, morphological Neandertal specimens are not directly dated but are contextually associated with the Châtelperronian, which contains bone points and beads. The association between Neandertals and this “transitional” assemblage has been controversial because of the lack either of a direct hominin radiocarbon date or of molecular confirmation of the Neandertal affiliation. Here we provide further evidence for a Neandertal–Châtelperronian association at the Grotte du Renne through biomolecular and chronological analysis. We identified 28 additional hominin specimens through zooarchaeology by mass spectrometry (ZooMS) screening of morphologically uninformative bone specimens from Châtelperronian layers at the Grotte du Renne. Next, we obtain an ancient hominin bone proteome through liquid chromatography-MS/MS analysis and error-tolerant amino acid sequence analysis. Analysis of this palaeoproteome allows us to provide phylogenetic and physiological information on these ancient hominin specimens. We distinguish Late Pleistocene clades within the genus Homo based on ancient protein evidence through the identification of an archaic-derived amino acid sequence for the collagen type X, alpha-1 (COL10α1) protein. We support this by obtaining ancient mtDNA sequences, which indicate a Neandertal ancestry for these specimens. Direct accelerator mass spectometry radiocarbon dating and Bayesian modeling confirm that the hominin specimens date to the Châtelperronian at the Grotte du Renne.

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Popova, Milena, Dessislava Gerginova, Boryana Trusheva, Svetlana Simova, Alfred Ngenge Tamfu, Ozgur Ceylan, Kerry Clark, and Vassya Bankova. "A Preliminary Study of Chemical Profiles of Honey, Cerumen, and Propolis of the African Stingless Bee Meliponula ferruginea." Foods 10, no. 5 (May 2, 2021): 997. http://dx.doi.org/10.3390/foods10050997.

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Recently, the honey and propolis of stingless bees have been attracting growing attention because of their health-promoting properties. However, studies on these products of African Meliponini are still very scarce. In this preliminary study, we analyzed the chemical composition of honey, two cerumen, and two resin deposits (propolis) samples of Meliponula ferruginea from Tanzania. The honey of M. ferruginea was profiled by NMR and indicated different long-term stability from Apis mellifera European (Bulgarian) honey. It differed significantly in sugar and organic acids content and had a very high amount of the disaccharide trehalulose, known for its bioactivities. We suggested trehalulose to be a potential marker for African stingless bee honey analogously to the recent proposal for Meliponini honey from Asia, South America, and Australia and demonstrated its easy discrimination by 13C NMR. Propolis and cerumen were studied by GC-MS (gas chromatography-mass spectometry). The samples contained mainly terpenoids (di-and triterpenes) but demonstrated qualitative and quantitative differences. This fact was an indication that possibly M. ferruginea has no strict preferences for resins used to construct and protect their nests. The antimicrobial and anti-quorum sensing properties of the two materials were also tested. These first results demonstrated that the honey, cerumen, and propolis of African stingless bees were rich in biologically active substances and deserved further research.

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