keyword
MENU ▼
Read by QxMD icon Read
search

Mass spectrometry

keyword
https://www.readbyqxmd.com/read/29151004/differentiation-of-wood-derived-vanillin-from-synthetic-vanillin-in-distillates-using-gc-c-irms-for-%C3%AE-13-c-analysis
#1
Katryna A van Leeuwen, Paul D Prenzler, Danielle Ryan, Mauro Paolini, Federica Camin
RATIONALE: Typical storage in oak barrels release in distillates different degradation products such as vanillin, which play an important role in their flavour and aroma. The addition of vanillin, as well as other aroma compounds, of different origin is prohibited by European laws. As vanillin samples from different sources have different δ(13) C values, the δ(13) C value could be used to determine whether the vanillin is authentic (lignin-derived), or if it has been added from another source (e...
November 18, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/29150981/systematic-proteomic-analysis-of-protein-methylation-in-prokaryotes-and-eukaryotes-revealed-distinct-substrate-specificity
#2
Min Zhang, Jun-Yu Xu, Hao Hu, Bang-Ce Ye, Minjia Tan
The studies of protein methylation mainly focus on lysine and arginine residues due to their diverse roles in essential cellular processes from gene expression to signal transduction. Nevertheless, atypical protein methylation occurring on amino acid residues, such as glutamine and glutamic acid, was largely neglected until recently. In addition, the systematic analysis for the distribution of methylation on different amino acids in various species is still lacking, which hinders our understanding of its functional roles...
November 18, 2017: Proteomics
https://www.readbyqxmd.com/read/29150928/application-of-high-speed-counter-current-chromatography-and-hplc-to-separate-and-purify-of-three-polyacetylenes-from-platycodon-grandiflorum
#3
Bao Chen, Zhengbo Liu, Yuwei Zhang, Wei Li, Yanjun Sun, Yufang Wang, Yanhua Wang, Yinshi Sun
Three polyacetylenes were isolated and purified from Platycodon grandiflorum A. DC for the first time by high-speed counter-current chromatography using a two-phase solvent system composed of hexane/ethyl acetate/methanol/water (1:31:1:31, v/v/v/v) and high-performance liquid chromatography with an Agilent ZORBAX(®) SB-C18 column (4.6 mm × 150 mm, 5 μm). After separation by high-speed counter-current chromatography and high-performance liquid chromatography, we obtained 3.5 mg of platetyolin A, 4.1 mg of platetyolin B, and 18...
November 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29150927/identification-of-proteins-drying-oils-waxes-and-resins-in-the-works-of-art-micro-samples-by-chromatographic-and-mass-spectrometric-techniques
#4
Bartłomiej Witkowski, Anna Duchnowicz, Monika Ganeczko, Agnieszka Laudy, Tomasz Gierczak, Magdalena Biesaga
Simplified method for simultaneous identification of proteins, drying oils, waxes and resins in the works-of-art samples was developed. Liquid chromatography with mass spectrometry and gas chromatography with mass spectrometry were used to identify natural materials most frequently encountered in historical paintings. Protein binders were extracted with ammonia and purified using miniaturized solid-phase microextraction (Omix tips) to efficiently suppress matrix interferences. Zwitterionic stationary phase was used for separation of sixteen underivatized amino acids analysis with hydrophilic interaction liquid chromatography that were subsequently quantified with liquid chromatography with mass spectrometry...
November 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29150926/viral-short-orfs-and-their-possible-functions
#5
REVIEW
Yaara Finkel, Noam Stern-Ginossar, Michal Schwartz
Definition of functional genomic elements is one of the greater challenges of the genomic era. Traditionally, putative short Open Reading Frames (sORFs) coding for less than 100 amino acids were disregarded due to computational and experimental limitations, however it has become clear over the past several years that translation of sORFs is pervasive and serves diverse functions. The development of ribosome profiling, allowing identification of translated sequences genome-wide, revealed wide-spread, previously unidentified translation events...
November 18, 2017: Proteomics
https://www.readbyqxmd.com/read/29150895/rapid-and-green-determination-of-58-fragrance-allergens-in-plush-toys
#6
Zhijuan Wang, Qing Zhang, Haiyu Li, Qing Lv, Wan Wang, Hua Bai
This paper presents a simple, rapid, and green method based on a static headspace gas chromatography with mass spectrometry for determining 58 fragrance allergens in plush toys. This study is the first to meet the requirement for simultaneously determining 66 fragrances, except for eight natural extracts restricted by the European Toy Safety Directive 2009/48/EC. A minimal amount of sample (20 mg) and acetone solvent (20 μL) were placed in a headspace vial. A gas-solid equilibration of fragrances between the headspace and the sample was achieved within 10 min under the vapor atmosphere of acetone at 200°C, which allowed the fragrances in the sample to be measured by gas chromatography with mass spectrometry...
November 17, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29150808/monitoring-enzymatic-degradation-of-emerging-contaminants-using-a-chip-based-robotic-nano-esi-ms-tool
#7
Lara F Stadlmair, Thomas Letzel, Johanna Graßmann
Up to now, knowledge of enzymes capable of degrading various contaminants of emerging concern (CEC) is limited, which is especially due to the lack of rapid screening methods. Thus, a miniaturized high-throughput setup using a chip-based robotic nanoelectrospray ionization system coupled to mass spectrometry has been developed to rapidly screen enzymatic reactions with environmentally relevant CECs. Three laccases, two tyrosinases, and two peroxidases were studied for their ability to transform ten pharmaceuticals and benzotriazole...
November 17, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29150804/using-citrus-aurantifolia-essential-oil-for-the-potential-biocontrol-of-colocasia-esculenta-taro-leaf-blight-caused-by-phytophthora-colocasiae
#8
Séverin Nguemezi Tchameni, Staelle Njamou Mbiakeu, Modeste Lambert Sameza, Pierre Michel Dongmo Jazet, François Tchoumbougnang
The aim of this work was to evaluate the antimicrobial activities of leaves and epicarp of Citrus aurantifolia essential oil against Phytophthora colocasiae, the causative agent of taro leaf blight. Oils were extracted by hydrodistillation, and their chemical composition was determined by gas chromatography and gas chromatography coupled with mass spectrometry. Antimicrobial activities of oils were tested in vitro against mycelium growth and sporangium production. In situ tests were done on healthy taro leaves, and the necrosis symptoms were evaluated...
November 17, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29150254/subcellular-distribution-and-biotransformation-of-phenanthrene-in-pakchoi-after-inoculation-with-endophytic-pseudomonas-sp-as-probed-using-hrms-coupled-with-isotope-labeling
#9
Kai Sun, Mussie Y Habteselassie, Juan Liu, Shunyao Li, Yanzheng Gao
Contamination of food-crops with polycyclic aromatic hydrocarbons (PAHs) poses a grave concern to food safety, especially when PAHs are internalized. We have demonstrated in our previous study that inoculation of crop with a phenanthrene-degrading endophytic Pseudomonas sp. Ph6-gfp could overcome this problem. Here, the subcellular distribution and biotransformation mechanism of phenanthrene in pakchoi (Brassica chinensis L.) seedlings with inoculation of Ph6-gfp were further investigated both in vitro and in vivo...
November 14, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/29150244/proteomic-analysis-of-follicular-fluid-from-tropically-adapted-goats
#10
Alexandre R Paula Junior, Mauricio F van Tilburg, Marina D P Lobo, Ana C O Monteiro-Moreira, Renato A Moreira, Carlos H S Melo, Joanna M G Souza-Fabjan, Airton A Araújo, Luciana M Melo, Dárcio I A Teixeira, Arlindo A Moura, Vicente J F Freitas
The present study was conducted to characterize the major proteome of ovarian follicular fluid from locally-adapted, "Canindé" goats in the northeast of Brazil. Eight estrous cycling goats received a hormonal treatment consisting of medroxyprogesterone acetate, D-cloprostenol and FSH. Fluid was collected by laparoscopy from small (<3mm), medium (3-4mm) and large (>4mm) follicles and then, proteins were analyzed by 2-D SDS-PAGE and tandem mass spectrometry. Thirty-six proteins were identified in the goat follicular fluid, including albumin, immunoglobulins, ceruloplasmin, complement factor B, alpha-1B-glycoprotein precursor, serotransferrin, complement C3 and serpins, among others...
November 6, 2017: Animal Reproduction Science
https://www.readbyqxmd.com/read/29150189/uranium-mobility-across-annual-growth-rings-in-three-deciduous-tree-species
#11
Kelly C McHugh, Elisabeth Widom, Henry B Spitz, Gregory C Wiles, Sam E Glover
Black walnut (Juglans nigra), slippery elm (Ulmus rubra), and white ash (Fraxinus americana) trees were evaluated as potential archives of past uranium (U) contamination. Like other metals, U mobility in annual growth rings of trees is dependent on the tree species. Uranium concentrations and isotopic compositions (masses 234, 235, 236, and 238) were analyzed by thermal ionization mass spectrometry to test the efficacy of using tree rings to retroactively monitor U pollution from the FFMPC, a U purification facility operating from 1951 to 1989...
November 14, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/29149843/characterization-of-a-novel-bioflocculant-from-a-marine-bacterium-and-its-application-in-dye-wastewater-treatment
#12
Zhen Chen, Zhipeng Li, Peize Liu, Yu Liu, Yuanpeng Wang, Qingbiao Li, Ning He
BACKGROUND: The identification of microorganisms with excellent flocculant-producing capability and optimization of the fermentation process are necessary for the wide-scale application of bioflocculants. Thus, we evaluated the flocculant-producing ability of a novel strain identified by the screening of marine bacteria, and we report for the first time the properties of the bioflocculant produced by Alteromonas sp. in the treatment of dye wastewater. RESULTS: A bioflocculant-producing bacterium was isolated from seawater and identified as Alteromonas sp...
November 17, 2017: BMC Biotechnology
https://www.readbyqxmd.com/read/29149806/occurrence-of-aflatoxin-m1-in-milk-samples-from-italy-analysed-by-online-spe-uhplc-ms-ms
#13
Luca Campone, Anna Lisa Piccinelli, Rita Celano, Imma Pagano, Rosa Di Sanzo, Sonia Carabetta, Mariateresa Russo, Luca Rastrelli
The occurrence of aflatoxin M1 in 69 milk samples collected in a south region of Italy in 2016 was evaluated. The samples were analysed using an automated method based on online SPE coupled with UHPLC tandem mass spectrometry. After a salt induced liquid-liquid extraction with acetonitrile to remove protein from milk, the extract was diluted with water and analysed using an automated online SPE MS/MS method. Among the analysed samples no one had AFM1 higher than the legally allowable limits whereas 71.4% of the other analysed samples were above the LOD of the method...
November 17, 2017: Natural Product Research
https://www.readbyqxmd.com/read/29149798/reconstructing-biosynthetic-pathway-of-the-plant-derived-cancer-chemopreventive-precursor-glucoraphanin-in-escherichia-coli
#14
Han Yang, Feixia Liu, Yin Li, Bo Yu
Epidemiological data confirmed a strong correlation between regular consumption of cruciferous vegetables and lower cancer risk. This cancer preventive property is mainly attributed to the glucosinolate products, such as glucoraphanin found in broccoli that is derived from methionine. Here we report the first successful reconstruction of the complete biosynthetic pathway of glucoraphanin from methionine in Escherichia coli via gene selection, pathway design, and protein engineering. We used branched-chain amino transferase 3 to catalyze two transamination steps to ensure the purity of precursor molecules and used cysteine as a sulfur donor to simplify the synthesis pathway...
November 17, 2017: ACS Synthetic Biology
https://www.readbyqxmd.com/read/29149735/carbamazepine-lamotrigine-levetiracetam-and-valproic-acid-in-dried-blood-spots-with-liquid-chromatography-tandem-mass-spectrometry-method-development-and-validation
#15
Camilla Linder, Anna Hansson, Sara Sadek, Lars L Gustafsson, Anton Pohanka
Monitoring of antiepileptic drugs in children with epilepsy require multiple visits at a clinic for blood collection. Dried blood spot sampling is an alternative way of collection, performed at home by self-collection and can save time and costs for patients and family members. The aim was to develop and validate an LC-MS/MS dried blood spot method for carbamazepine, lamotrigine, levetiracetam and valproic acid with the requirements of using standard equipment and material in a routine laboratory setting. Whatman-903 filter paper was utilized, and discs were punched into a 96 well plate with an automated puncher and barcode reading...
November 4, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29149729/functionalized-gold-nanoparticles-as-affinity-nanoprobes-for-multiple-lectins
#16
Karuppuchamy Selvaprakash, Yu-Chie Chen
Glycan-lectin interactions are commonly observed in nature. Analytical methods, which are used to detect lectins that rely on the use of glycan ligand-modified nanoprobes as affinity probes, have been developed. Most of the existing methods are focused on the use of synthetic glycan ligands. Nevertheless, naturally available glycoproteins, such as ovalbumin in chicken egg whites, are good sources for fabricating glycan-immobilized nanoprobes. In this study, we generated functionalized gold nanoparticles (Au NPs) from a one-pot reaction by reacting chicken egg white (cew) proteins with aqueous tetrachloroaurate...
November 8, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/29149712/detection-of-perfluoroalkyl-acids-and-sulphonates-in-italian-eel-samples-by-hplc-hrms-orbitrap
#17
Luca Maria Chiesa, Maria Nobile, Elisa Pasquale, Claudia Balzaretti, Petra Cagnardi, Doriana Tedesco, Sara Panseri, Francesco Arioli
Perfluoroalkyl substances (PFASs) contain one or more carbon-bound hydrogens substituted by fluorine. Since the 1950s, these compounds have been used to manufacture fat- and water-resistant fabrics, paper and food containers, and to produce photographic films, firefighting foams, detergents and insecticides. The widespread use and global distribution of PFASs, have led to their accumulation in the environment. Food, particularly fish and other seafood, is considered the main route of human exposure to PFASs...
October 27, 2017: Chemosphere
https://www.readbyqxmd.com/read/29149702/an-hplc-tandem-mass-spectrometry-for-quantification-of-et-26-hcl-and-its-major-metabolite-in-plasma-and-application-to-a-pharmacokinetic-study-in-rats
#18
Xu Chen, Wensheng Zhang, Sandy Rios, Miriam B Morkos, Xiaoli Ye, Gen Li, Xuehua Jiang, Zhijun Wang, Ling Wang
ET-26-HCl is a new analog of etomidate, a short-acting anesthetic drug, with less adrenal cortex inhibition. The pharmacokinetics of ET-26-HCl in rats needs to be determined for future clinical trials in human subjects. In order to facilitate the pharmacokinetic study, a liquid chromatography based tandem mass spectrometric (HPLC-MS/MS) method was developed and validated for quantification of ET-26-HCl and its major metabolite, ET-26-acid. These two compounds and gabapentin (internal standard) were extracted using a protein precipitation method with methanol and detected by Multiple Reaction Monitoring of m/z transition of 275...
November 8, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29149685/simultaneous-drug-identification-in-urine-of-sexual-assault-victims-by-using-liquid-chromatography-tandem-mass-spectrometry
#19
Hei Hwa Lee, Suen Chi Chen, Jong Feng Lee, Hsin Yu Lin, Bai Hsiun Chen
According to domestic and international epidemiological investigation, the proportion of substance involved sexual assault has the trend of ascent. In the past, laboratory methods that investigated urine sample of the sexual assault victims was to screen with enzyme immunoassay and then confirmed with mass spectrometry. The objective of the study is to simultaneously identify abused drugs in 126 decoded urine samples of sexual assault victims by liquid chromatography tandem mass spectrometry. The instrument was operated in multiple-reaction monitoring with an electro-spray positive ionization mode...
November 11, 2017: Forensic Science International
https://www.readbyqxmd.com/read/29149484/comparative-analysis-of-proteomes-between-diabetic-and-normal-human-sperm-insights-into-the-effects-of-diabetes-on-male-reproduction-based-on-the-regulation-of-mitochondria-related-proteins
#20
Tian An, Yue-Fen Wang, Jia-Xian Liu, Yan-Yun Pan, Yu-Fei Liu, Zhong-Chen He, Fang-Fang Mo, Jun Li, Li-Hua Kang, Yu-Jie Gu, Bo-Han Lv, Si-Huan Gao, Guang-Jian Jiang
This study sought to identify sources of the reduced fertility of men with type 2 diabetes mellitus. Significant reductions in semen volume, sperm concentration, and total sperm count were observed in diabetic individuals, while transmission electron microscopy revealed that the structure of mitochondria in the tail of sperm from diabetic patients was damaged. Proteins potentially associated with these sperm defects were identified using proteomics. Isobaric tagging for relative and absolute quantitation labeling and high-performance liquid chromatography-tandem mass spectrometry allowed us to identify 357 proteins significantly differentially expressed in diabetic versus control semen (>1...
November 17, 2017: Molecular Reproduction and Development
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"