keyword
MENU ▼
Read by QxMD icon Read
search

Mass spectrometry

keyword
https://www.readbyqxmd.com/read/28434194/cytotoxic-triterpenoids-from-the-stalks-of-microtropis-triflora
#1
Xiao-Wei Zhang, Kui-Wu Wang, Man-Qing Zhou
Bioassay-guided phytochemcal investigation of the stalks of Microtropis triflora Merr. et Freem led to the isolation of ten triterpenes 1-10, including one novel compound 24-epoxy-2α, 24-dihydroxy-29-friedelanoic acid (1). Their chemical structures were identified on the basis of spectroscopic analysis, including HRESI mass spectrometry, 1D and 2D NMR ((1) H, (13) C, (1) H-(1) H COSY, HSQC, HMBC and NOESY), and by comparison with the data reported. The cytotoxicities of the compounds 1-10 against a panel of cultured human tumor cell lines (Bcap37, SMMC7721, Hela, CNE) were evaluated...
April 23, 2017: Chemistry & Biodiversity
https://www.readbyqxmd.com/read/28434171/peroxidatic-cysteine-residue-of-peroxiredoxin-2-separated-from-human-red-blood-cells-treated-by-tert-butyl-hydroperoxide-is-hyperoxidized-into-sulfinic-and-sulfonic-acids
#2
Yo-Ichi Ishida, Mariko Aki, Sohta Fujiwara, Masami Nagahama, Yuki Ogasawara
Peroxiredoxin 2 (Prx2) is a redox enzyme that is abundantly expressed in red blood cells (RBCs) and has been the focus of clinical attention for monitoring the oxidative status. We previously developed a method to quantify the reduced and hyperoxidized forms of Prx2 in human RBCs using reverse-phase high-performance liquid chromatography (HPLC). In the present study, we investigated the hyperoxidative status of Prx2 at the molecular level in a post-translational modification analysis using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system...
April 22, 2017: Human Cell
https://www.readbyqxmd.com/read/28434116/activation-of-the-serotonin-pathway-is-associated-with-poor-outcome-in-copd-exacerbation-results-of-a-long-term-cohort-study
#3
Marc A Meier, Manuel Ottiger, Alaadin Vögeli, Christian Steuer, Luca Bernasconi, Robert Thomann, Mirjam Christ-Crain, Christoph Henzen, Claus Hoess, Werner Zimmerli, Andreas Huber, Beat Mueller, Philipp Schuetz
BACKGROUND/INTRODUCTION: Indoleamine 2,3-dioxygenase (IDO) metabolizes tryptophan to kynurenine. An increase of its activity is associated with severity in patients with pneumonia. In chronic obstructive pulmonary disease (COPD) patients, an elevation of serotonin has been reported. Experimental models showed that cigarette smoke inhibits monoamine oxidase (MAO) leading to higher levels of serotonin. We investigated the prognostic ability of tryptophan, serotonin, kynurenine, IDO, and tryptophan hydroxylase (TPH) to predict short- and long-term outcomes in patients with a COPD exacerbation...
April 22, 2017: Lung
https://www.readbyqxmd.com/read/28433954/lipidomic-profile-in-three-species-of-dinoflagellates-amphidinium-carterae-cystodinium-sp-and-peridinium-aciculiferum-containing-very-long-chain-polyunsaturated-fatty-acids
#4
Tomáš Řezanka, Jaromír Lukavský, Linda Nedbalová, Karel Sigler
This study describes the identification of very long chain polyunsaturated fatty acids (VLCPUFAs) in three strains of dinoflagellates (Amphidinium carterae, Cystodinium sp., and Peridinium aciculiferum). The strains were cultivated and their lipidomic profiles were obtained by high resolution mass spectrometry with the aid of positive and negative electrospray ionization (ESI) mode by Orbitrap apparatus. Hydrophilic interaction liquid chromatography (HILIC/ESI) was used to separate major lipid classes of the three genera of dinoflagellates by neutral loss scan showing the ion [M + H-28:8](+), where 28:8 was octacosaoctaenoic acid, and by precursor ion scanning of ions at m/z 407, which was an ion corresponding to the structure of acyl of 28:8 acid (C27H39COO(-))...
April 20, 2017: Phytochemistry
https://www.readbyqxmd.com/read/28433874/systematically-characterize-the-absorbed-effective-substances-of-wutou-decoction-and-their-metabolic-pathways-in-rat-plasma-using-uhplc-q-tof-ms-combined-with-a-target-network-pharmacological-analysis
#5
Tengfei Xu, Shizhe Li, Yufei Sun, Zifeng Pi, Shu Liu, Fengrui Song, Zhiqiang Liu
Wu-tou Decoction (WTD) is a famous traditional Chinese medicine (TCM) formula which is applied to treat arthritis and pain of joints. In this study, a sensitive and rapid method was developed for the separation and identification of the absorbed constituents and metabolites of WTD in the rats plasma by ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). A total of 22 absorbed prototype constituents and 49 metabolites were identified or tentatively characterized in dosed plasma...
April 13, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28433834/antimicrobial-and-anticancer-photodynamic-activity-of-a-phthalocyanine-photosensitizer-with-n-methyl-morpholiniumethoxy-substituents-in-non-peripheral-positions
#6
Jolanta Dlugaszewska, Wojciech Szczolko, Tomasz Koczorowski, Paulina Skupin-Mrugalska, Anna Teubert, Krystyna Konopka, Malgorzata Kucinska, Marek Murias, Nejat Düzgüneş, Jadwiga Mielcarek, Tomasz Goslinski
Photodynamic therapy involves the use of a photosensitizer that is irradiated with visible light in the presence of oxygen, resulting in the formation of reactive oxygen species. A novel phthalocyanine derivative, the quaternary iodide salt of magnesium(II) phthalocyanine with N-methyl morpholiniumethoxy substituents, was synthesized, and characterized. The techniques used included mass spectrometry (MALDI TOF), UV-vis, NMR spectroscopy, and photocytotoxicity against bacteria, fungi and cancer cells. The phthalocyanine derivative possessed typical characteristics of compounds of the phthalocyanine family but the effect of quaternization was observed on the optical properties, especially in terms of absorption efficiency...
April 8, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28433833/in-vitro-antitumor-activity-metal-uptake-and-reactivity-with-ascorbic-acid-and-bsa-of-some-gold-iii-complexes-with-n-n-ethylenediamine-bidentate-ester-ligands
#7
Nebojša Pantelić, Bojana B Zmejkovski, Branka Kolundžija, Marija Đorđić Crnogorac, Jelena M Vujić, Biljana Dojčinović, Srećko R Trifunović, Tatjana P Stanojković, Tibor J Sabo, Goran N Kaluđerović
Four novel gold(III) complexes of general formulae [AuCl2{(S,S)-R2eddl}]PF6 (R2eddl=O,O'-dialkyl-(S,S)-ethylenediamine-N,N'-di-2-(4-methyl)pentanoate, R=n-Pr, n-Bu, n-Pe, i-Bu; 1-4, respectively), were synthesized and characterized by elemental analysis, UV/Vis, IR, and NMR spectroscopy, as well as high resolution mass spectrometry. Density functional theory calculations pointed out that (R,R)-N,N'-configuration diastereoisomers were energetically the most favorable. Duo to high cytotoxic activity complex 3 was chosen for stability study in DMSO, no decomposition occurs within 24h, and for the reaction with ascorbic acid in which was reduced immediately...
April 4, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28433799/affinity-proteomics-exploration-of-melanoma-identifies-proteins-in-serum-with-associations-to-t-stage-and-recurrence
#8
Sanna Byström, Claudia Fredolini, Per-Henrik Edqvist, Etienne-Nicholas Nyaiesh, Kimi Drobin, Mathias Uhlén, Michael Bergqvist, Fredrik Pontén, Jochen M Schwenk
BACKGROUND: Blood-based proteomic profiling may aid and expand our understanding of diseases and their different phenotypes. The aim of the presented study was to profile serum samples from patients with malignant melanoma using affinity proteomic assays to describe proteins in the blood stream that are associated to stage or recurrence of melanoma. MATERIAL AND METHODS: Multiplexed protein analysis was conducted using antibody suspension bead arrays. A total of 232 antibodies against 132 proteins were selected from (i) a screening with 4595 antibodies and 32 serum samples from melanoma patients and controls, (ii) antibodies used for immunohistochemistry, (iii) protein targets previously related with melanoma...
April 20, 2017: Translational Oncology
https://www.readbyqxmd.com/read/28433761/a-glycoproteomic-approach-reveals-that-the-s-layer-glycoprotein-of-lactobacillus-kefiri-cidca-83111-is-o-and-n-glycosylated
#9
Gustavo J Cavallero, Mariano Malamud, Adriana C Casabuono, M de Los Ángeles Serradell, Alicia S Couto
In Gram-positive bacteria, such as lactic acid bacteria, general glycosylation systems have not been documented so far. The aim of this work was to characterize in detail the glycosylation of the S-layer protein of Lactobacillus kefiri CIDCA 83111. A reductive β-elimination treatment followed by anion exchange high performance liquid chromatography analysis was useful to characterize the O-glycosidic structures. MALDI-TOF mass spectrometry analysis confirmed the presence of oligosaccharides bearing from 5 to 8 glucose units carrying galacturonic acid...
April 19, 2017: Journal of Proteomics
https://www.readbyqxmd.com/read/28433749/novel-sulphur-containing-imatinib-metabolites-found-by-untargeted-lc-hrms-analysis
#10
Ivo Vrobel, David Friedecký, Edgar Faber, Lukáš Najdekr, Kateřina Mičová, Radana Karlíková, Tomáš Adam
Untargeted metabolite profiling using high-resolution mass spectrometry coupled with liquid chromatography (LC-HRMS), followed by data analysis with the Compound Discoverer 2.0™ software, was used to study the metabolism of imatinib in humans with chronic myeloid leukemia. Plasma samples from control (drug-free) and patient (treated with imatinib) groups were analyzed in full-scan mode and the unknown ions occurring only in the patient group were then, as potential imatinib metabolites, subjected to multi-stage fragmentation in order to elucidate their structure...
April 19, 2017: European Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28433670/evaluation-of-the-routine-antimicrobial-susceptibility-testing-results-of-clinically-significant-anaerobic-bacteria-in-a-slovenian-tertiary-care-hospital-in-2015
#11
Samo Jeverica, Urša Kolenc, Manica Mueller-Premru, Lea Papst
The aim of our study was to determined antimicrobial susceptibility profiles of 2673 clinically significant anaerobic bacteria belonging to the major genera, isolated in 2015 in a large tertiary-care hospital in Slovenia. The species identification was performed by MALDI-TOF mass spectrometry. Antimicrobial susceptibility was determined immediately at the isolation of the strains against: penicillin, co-amoxiclav, imipenem, clindamycin and metronidazole, using gradient diffusion methodology and EUCAST breakpoints...
April 19, 2017: Anaerobe
https://www.readbyqxmd.com/read/28433638/metabolomic-analysis-for-combined-hepatotoxicity-of-chlorpyrifos-and-cadmium-in-rats
#12
Ming-Yuan Xu, Pan Wang, Ying-Jian Sun, Yi-Jun Wu
Pesticides and heavy metals are widespread environmental pollutants. Although the acute toxicity of organophosphorus pesticide chlorpyrifos (CPF) and toxic heavy metal cadmium (Cd) is well characterized, the combined toxicity of CPF and Cd, especially the hepatotoxicity of the two chemicals with long-term exposure at a low dose, remained unclear. In this study, we investigated the toxicity in the liver of rats upon subchronic exposure to CPF and Cd at environmentally relevant doses. Rats were given three different doses (1/135 LD50, 1/45 LD50 and 1/15 LD50) of CPF and Cd as well as their mixtures by oral gavage for 90 days...
April 19, 2017: Toxicology
https://www.readbyqxmd.com/read/28433626/thrombin-impairs-human-endometrial-endothelial-angiogenesis-implications-for-progestin-only-contraceptive-induced-abnormal-uterine-bleeding
#13
John P Shapiro, Ozlem Guzeloglu-Kayisli, Umit A Kayisli, Nihan Semerci, S Joseph Huang, Sefa Arlier, Kellie Larsen, Paolo Fadda, Frederick Schatz, Charles J Lockwood
OBJECTIVE: Progestin-only contraceptives induce abnormal uterine bleeding, accompanied by pro-thrombin leakage from dilated endometrial microvessels and increased thrombin generation by human endometrial stromal cell (HESC)-expressed tissue factor. Initial studies of the thrombin-treated HESC secretome identified elevated levels of cleaved chondroitin sulfate proteoglycan 4 (CSPG4), impairing pericyte-endothelial interactions. Thus, we investigated direct and CSPG4-mediated effects of thrombin in eliciting abnormal uterine bleeding by disrupting endometrial angiogenesis...
April 19, 2017: Contraception
https://www.readbyqxmd.com/read/28433611/preanalytical-variables-for-liquid-chromatography-mass-spectrometry-lc-ms-analysis-of-human-blood-specimens
#14
REVIEW
Gian Luca Salvagno, Elisa Danese, Giuseppe Lippi
The use of liquid chromatography-mass spectrometry (LC-MS) for both diagnostics and research purposes is rapidly growing in clinical laboratories. As for more conventional areas of in vitro diagnostic testing, many preanalytical variables have an impact on these techniques and may hence jeopardize the quality of tests results. The leading preanalytical variables include patient preparation, the nature of the blood collection tubes and additives, interference from spurious hemolysis, sample handling and management, composition of blood tubes, contamination, as well as storage conditions...
April 19, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28433607/transfer-of-vaginal-chloramphenicol-to-circulating-blood-in-pregnant-women-and-its-relationship-with-their-maternal-background-and-neonatal-health
#15
Satoe Harauchi, Takashi Osawa, Naoko Kubono, Hiroaki Itoh, Takafumi Naito, Junichi Kawakami
Few clinical studies have determined the quantitative transfer of vaginal chloramphenicol to circulating blood in pregnant women. This study aimed to evaluate the plasma concentration of chloramphenicol in pregnant women treated with trans-vaginal tablets and its relationship with maternal background and neonatal health. Thirty-seven pregnant women treated with 100 mg of trans-vaginal chloramphenicol once daily for bacterial vaginosis and its suspected case were enrolled. The plasma concentration of chloramphenicol was determined using liquid chromatography coupled to tandem mass spectrometry at day 2 or later after starting the medication...
April 19, 2017: Journal of Infection and Chemotherapy: Official Journal of the Japan Society of Chemotherapy
https://www.readbyqxmd.com/read/28433551/in-vitro-investigation-of-metabolic-profiling-of-newly-developed-topoisomerase-inhibitors-ethyl-fluorescein-hydrazones-etflhs-in-rlms-by-lc-ms-ms
#16
Adnan A Kadi, Nasser S Al-Shakliah, Wencui Yin, A F M Motiur Rahman
Metabolic profiling of newly reported five topoisomerase inhibitors namely ethyl fluorescein hydrazones (EtFLHs) were studied in rat liver microsomes (RLMs) and the data were acquired in a liquid chromatography (LC) ion trap mass spectrometry. Hydroxyl group containing EtFLHs derivatives (1-3) were bio-transformed into hydrolyzed, mono-hydroxylated and hydrolyzed together with mono-hydroxylated metabolites. On the other hand, nitro and methoxy groups containing EtFLHs derivatives (4-5) were bio-transformed into hydrolyzed, hydrolyzed together with mono-hydroxylated and azo-reductive metabolites in the presence of NADPH...
April 6, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28433521/determination-of-cyclopeptide-toxins-in-amanita-subpallidorosea-and-amanita-virosa-by-high-performance-liquid-chromatography-coupled-with-high-resolution-mass-spectrometry
#17
Jiahui Wei, Jianfeng Wu, Jia Chen, Bidong Wu, Zhengmi He, Ping Zhang, Haijiao Li, Chengye Sun, Chang Liu, Zuohong Chen, Jianwei Xie
Amanita subpallidorosea is a recently discovered lethal Amanita sect. Phalloideae species found in China that is clustered with A. virosa in the same clade based on molecular phylogenetic analysis. However, the cyclopeptide toxin contents of these lethal mushrooms remain poorly studied. In this study, the cyclopeptide toxins in A. subpallidorosea were reported for the first time and the cyclopeptide compositions of A. subpallidorosea and A. virosa species were systematically analyzed. Thirteen cyclopeptides and two unknown compounds were identified or observed from these two lethal mushrooms by high-performance liquid chromatography coupled with high-resolution mass spectrometry...
April 19, 2017: Toxicon: Official Journal of the International Society on Toxinology
https://www.readbyqxmd.com/read/28433489/analysis-of-the-oligosaccharides-in-japanese-rice-wine-sake-by-hydrophilic-interaction-liquid-chromatography-time-of-flight-mass-spectrometry
#18
Masafumi Tokuoka, Chihiro Honda, Akira Totsuka, Hitoshi Shindo, Masaru Hosaka
A traditional Japanese alcoholic beverage, sake, contains several oligosaccharides, which are associated with the taste of sake; however, little is known about the specific molecular species and concentrations of oligosaccharides in sake. Here, we developed an analytical method using hydrophilic interaction liquid chromatography-time-of-flight/mass spectrometry (HILIC-TOF/MS) which successfully detects the oligosaccharides in sake. A series of oligosaccharides with successive degree of polymerization (DP) values up to 18 were identified in sake for the first time, which we have named sake oligosaccharides (SAOs)...
April 19, 2017: Journal of Bioscience and Bioengineering
https://www.readbyqxmd.com/read/28433435/fabric-phase-sorptive-extraction-as-a-reliable-tool-for-rapid-screening-and-detection-of-freshness-markers-in-oranges
#19
M Aznar, S Úbeda, C Nerin, A Kabir, K G Furton
A simple, fast and sensitive analyte extraction method based on fabric phase sorptive extraction (FPSE) followed by gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC-QTOF-MS) analysis was developed for the analysis of 12 volatile compounds that represent most of the principal chemical families possessing different polarities and volatilities. Five FPSE media coated with different sol-gel sorbent chemistries having different polarities and selectivities were studied: long chain poly(dimethylsiloxane) (PDMS), short chain poly(tetrahydrofuran) (PTHF), Carbowax 20M (CW20M), short chain poly(dimethyl siloxane) (SC PDMS) and polyethylene glycol-polypropylene glycol-polyethylene glycol triblock copolymer (PEG-PPG-PEG)...
April 8, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28433057/low-cost-humic-acid-bonded-silica-as-an-effective-solid-phase-extraction-sorbent-for-convenient-determination-of-aflatoxins-in-edible-oils
#20
Neng-Zhi Zhou, Ping Liu, Xiao-Chuan Su, Yan-Hua Liao, Ning-Sheng Lei, Yong-Hong Liang, Shao-Huan Zhou, Wen-Si Lin, Jie Chen, Yu-Qi Feng, Yang Tang
Aflatoxins (AFs) are highly toxic, mutagenic, carcinogenic, and teratogenic secondary metabolites produced by the toxigenic fungi Aspergillus flavus and Aspergillus parasiticus. AFs tend to contaminate a wide range of foods which is a serious and recurring food safety problem worldwide. Currently, immunoaffinity chromatography (IAC) has become the most conventional sample clean-up method for determining AFs in foodstuffs. However, IAC method is limited in the large-scale food analysis because it requires the use of expensive disposable cartridges and the IA procedure is time-consuming...
June 1, 2017: Analytica Chimica Acta
keyword
keyword
10931
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"