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https://www.readbyqxmd.com/read/28645063/assessing-phosphatidylethanol-peth-levels-reflecting-different-drinking-habits-in-comparison-to-the-alcohol-use-disorders-identification-test-c-audit-c
#1
Alexandra Schröck, Friedrich M Wurst, Natasha Thon, Wolfgang Weinmann
In addition to monitoring problematic or harmful alcohol consumption, drinking experiments indicated the potential of phosphatidylethanols (PEth) in abstinence monitoring. To date, no profound evaluation of thresholds for the differentiation of abstinence from moderate drinking and for detection of excessive consumption based on PEth homologues exists. Investigations with a large group of healthy volunteers (n=300) were performed to establish PEth reference values reflecting different drinking habits. Blood samples were analyzed for PEth 16:0/18:1 and 16:0/18:2 by online-SPE-LC-MS/MS method...
June 13, 2017: Drug and Alcohol Dependence
https://www.readbyqxmd.com/read/28645021/development-a-validated-highly-sensitive-lc-ms-ms-method-for-simultaneous-quantification-of-ledipasvir-sofosbuvir-and-its-major-metabolite-gs-331007-in-human-plasma-application-to-a-human-pharmacokinetic-study
#2
Ola M Abdallah, Ahmed M Abdel-Megied, Amira S Gouda
A highly sensitive and rapid LC-MS/MS method was developed, fully optimized and validated for the simultaneous determination of Ledipasvir (LED) and Sofosbuvir (SOF) in the presence of its major metabolite GS-331007 in human plasma using Daclatasvir as internal standard (IS). The extraction of analytes and IS from plasma was performed using liquid-liquid extraction with ethyl acetate. The chromatographic separation of these prepared samples was achieved on Xterra MS C8 column (4.6×50mm,5μm) using gradient elution with a mobile phase of ammonium formate buffer (pH 3...
June 20, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28643431/a-study-of-the-origin-of-chloramphenicol-isomers-in-honey
#3
Dmytro Yanovych, Bjorn Berendsen, Zvenyslava Zasadna, Mariana Rydchuk, Tobias Czymai
Due to the unexpected detection of chloramphenicol isomer residues in honey, we have studied the hypothesis of unauthorized or unintended use of unregistered veterinary drug preparations. First we have investigated honey samples in which a discrepancy was observed between the results of the immunological screening methods and the confirmatory LC-MS/MS method. In all samples, previously identified to be contaminated with the banned antibiotic chloramphenicol according to LC-MS/MS only, the presence of dextramycin (SS-para isomer of chloramphenicol) was detected by chiral LC-MS/MS...
June 22, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28643405/reassessment-of-the-access-testosterone-chemiluminescence-assay-and-comparison-with-lc-ms-method
#4
Ruggero Dittadi, Mara Matteucci, Elisa Meneghetti, Rudina Ndreu
AIM OF THE STUDY: To reassess the imprecision and Limit of Quantitation, to evaluate the cross-reaction with dehydroepiandrosterone-sulfate (DHEAS), the accuracy toward liquid chromatography-mass spectrometry (LC-MS) and the reference interval of the Access Testosterone method, performed by DxI immunoassay platform (Beckman Coulter). MATERIAL AND METHODS: Imprecision was evaluated testing six pool samples assayed in 20 different run using two reagents lots. The cross-reaction with DHEAS was studied both by a displacement curve and by spiking DHEAS standard in two serum samples with known amount of testosterone...
June 23, 2017: Journal of Clinical Laboratory Analysis
https://www.readbyqxmd.com/read/28643348/the-construction-of-a-panel-of-serum-amino-acids-for-the-identification-of-early-chronic-kidney-disease-patients
#5
Rui Li, Jinna Dai, Hui Kang
BACKGROUND: Serum creatinine, urea, and cystatin-c are standardly used for the evaluation of renal function in the clinic. However, some patients have chronic kidney disease but still retain kidney function; a conventional serum index in these patients can be completely normal. Serum amino acid levels can reflect subtle changes in metabolism and are closely related to renal function. Here, we investigated how amino acids change as renal impairment increases. METHODS: Subjects were divided into three groups by renal function glomerular filtration rate: healthy controls, patients with chronic kidney disease with normal kidney function, and patients with chronic kidney disease with decreased kidney function group...
June 23, 2017: Journal of Clinical Laboratory Analysis
https://www.readbyqxmd.com/read/28643233/assessing-environmental-exposure-to-%C3%AE-n-methylamino-l-alanine-bmaa-in-complex-sample-matrices-a-comparison-of-the-three-most-popular-lc-ms-ms-methods
#6
Teesha C Baker, Fiona J M Tymm, Susan J Murch
β-N-Methylamino-L-alanine (BMAA) is a naturally occurring non-protein amino acid produced by cyanobacteria, accumulated through natural food webs, found in mammalian brain tissues. Recent evidence indicates an association between BMAA and neurological disease. The accurate detection and quantification of BMAA in food and environmental samples are critical to understanding BMAA metabolism and limiting human exposure. To date, there have been more than 78 reports on BMAA in cyanobacteria and human samples, but different methods give conflicting data and divergent interpretations in the literature...
June 22, 2017: Neurotoxicity Research
https://www.readbyqxmd.com/read/28643224/establishment-of-a-3d-cell-culture-model-of-primary-bovine-mammary-epithelial-cells-extracted-from-fresh-milk
#7
Maria Hillreiner, Nadine I Müller, Heiner M Koch, Christiane Schmautz, Bernhard Küster, Michael W Pfaffl, Heike Kliem
For the investigation of molecular processes underlying diseases of the bovine mammary gland, primary bovine mammary epithelial cells (pbMEC) are used. They are known to contribute to the innate immune system of the bovine mammary gland. The functionality of pbMEC depends on the maintenance of in vivo characteristics. So far, the optimization of pbMEC culture conditions was intended in a variety of experiments. For this purpose, most of the studies used stable cell lines or primary cells obtained from udder biopsies of slaughtered animals...
June 22, 2017: In Vitro Cellular & Developmental Biology. Animal
https://www.readbyqxmd.com/read/28642677/a-novel-workflow-combining-plaque-imaging-plaque-and-plasma-proteomics-identifies-biomarkers-of-human-coronary-atherosclerotic-plaque-disruption
#8
Regent Lee, Roman Fischer, Philip D Charles, David Adlam, Alessandro Valli, Katalin Di Gleria, Rajesh K Kharbanda, Robin P Choudhury, Charalambos Antoniades, Benedikt M Kessler, Keith M Channon
BACKGROUND: Atherosclerotic plaque rupture is the culprit event which underpins most acute vascular syndromes such as acute myocardial infarction. Novel biomarkers of plaque rupture could improve biological understanding and clinical management of patients presenting with possible acute vascular syndromes but such biomarker(s) remain elusive. Investigation of biomarkers in the context of de novo plaque rupture in humans is confounded by the inability to attribute the plaque rupture as the source of biomarker release, as plaque ruptures are typically associated with prompt down-stream events of myocardial necrosis and systemic inflammation...
2017: Clinical Proteomics
https://www.readbyqxmd.com/read/28641832/ionic-liquid-based-vortex-assisted-liquid-liquid-microextraction-combined-with-liquid-chromatography-mass-spectrometry-for-the-determination-of-bisphenols-in-thermal-papers-with-the-aid-of-response-surface-methodology
#9
Ankita Asati, G N V Satyanarayana, Smita Panchal, Ravindra Singh Thakur, Nasreen G Ansari, Devendra K Patel
A sensitive, rapid and efficient ionic liquid-based vortex assisted liquid-liquid microextraction (IL-VALLME) with Liquid Chromatography Mass spectrometry (LC-MS/MS) method is proposed for the determination of bisphenols in thermal paper. Extraction factors were systematically optimized by response surface methodology. Experimental factors showing significant effects on the analytical responses were evaluated using design of experiment. The limit of detection for Bisphenol-A (BPA) and Bisphenol-S (BPS) in thermal paper were 1...
June 16, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28641559/a-stepwise-approach-for-the-isolation-and-the-identification-of-chemically-reactive-exofacial-protein-thiols
#10
Gabriele Candiani, Elisa Fasoli
The plasma membrane controls the selective internalization of (macro)molecules through different mechanisms, often relaying on specialized outward-facing carriers such as exofacial proteins thiols (EPTs). Although the interchange of critical thiols and disulphides between EPTs and exogenous cargoes is the first critical event, the identification of specific cell interactors remains to be thoroughly explored. We herein devise an enabling methodology for the isolation and identification of a subset of EPTs, named chemically reactive EPS, which are potential theranostic targets...
June 20, 2017: Protein and Peptide Letters
https://www.readbyqxmd.com/read/28641536/overview-of-forensic-toxicology-yesterday-today-and-in-the-future
#11
Heesun Chung, Sanggil Choe
BACKGROUND: The scope of forensic toxicology has been tremendously expanded over the past 50 years. From two general sections forensic toxicology can be further classified into 8-9 sections. METHODS: The most outstanding improvement in forensic toxicology is the changes brought by instrumental development. The field of forensic toxicology was revolutionized by the development of immunoassay and bench-top GC-MS in the 1980's and LC-MS-MS in 2000's. Detection of trace amounts of analytes has allowed the use of new specimens such as hair and oral fluids, along with blood and urine...
June 22, 2017: Current Pharmaceutical Design
https://www.readbyqxmd.com/read/28641534/interest-of-single-hair-analysis-to-document-drug-exposure-literature-review-and-a-case-report-involving-zuclopenthixol
#12
Nathalie Allibe, Pascal Kintz, Amandine Faure, François Paysant, Anne-Pascale Michard-Lenoir, Françoise Stanke-Labesque, Virginie Scolan, Hélène Eysseric-Guerin
The analysis of hair to detect drugs and drugs of abuse is performed in various contexts, including child protection cases, abstinence control programs, and workplace drug testing. This alternative matrix offers several advantages, such as a large detection window (months) and non-invasive collection. Segmental analysis of multiple hair strands for drugs and metabolites has been widely reported in the literature over the past three decades, whereas a review of the literature showed that there are only 26 articles that report the analysis of a single hair...
June 22, 2017: Current Pharmaceutical Design
https://www.readbyqxmd.com/read/28641500/levels-of-8-oxo-dgsn-and-8-oxo-gsn-in-random-urine-are-consistent-with-24%C3%A2-h-urine-in-healthy-subjects-and-patients-with-renal-disease
#13
Yong-Hui Mao, Qing-Hua Weng, Leng-Nan Xu, Xiang-Yu Li, Ban Zhao, Ying Sun, Jing-Jing Nie, Ji-Hong Hu, Qi Zhou, Li-Qun Zhang, Jian Guo, Ming-Zhang Zuo, Sadayoshi Ito, Jian-Ping Cai
Oxidatively generated damage to nucleic acids may play an important role in the pathophysiological processes of a variety of diseases. 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGsn) and 8-oxo-7,8-dihydroguanosine (8-oxo-Gsn) are oxidatively generated products of DNA and RNA, respectively. Our previous studies have suggested that the amounts of 8-oxo-dGsn and 8-oxo-Gsn in urine were considerably higher than other body fluid or tissue. The aim of this study was to investigate whether 8-oxo-dGsn and 8-oxo-Gsn levels in random urine samples are consistent with those in 24 h urine samples in healthy subjects and patients with renal disease...
June 23, 2017: Free Radical Research
https://www.readbyqxmd.com/read/28640579/rapid-and-robust-quantification-of-p-xyleneselenocyanate-in-plasma-via-derivatization
#14
Wenyi Zheng, Fadwa Benkessou, Brigitte Twelkmeyer, Siyao Wang, Tobias Ginman, Håkan Ottosson, Manuchehr Abedi-Valugerdi, Maria Angels Subirana, Ying Zhao, Moustapha Hassan
p-Xyleneselenocyanate (p-XSC) is one of the most investigated selenium compounds in cancer-prevention and -therapy. Despite the potent anti-cancer property, there is still no proper method to perform the quantitative analysis of p-XSC in plasma. In this investigation, we aimed at developing a method based on liquid chromatography-mass spectrometry (LC-MS) for the measurement of p-XSC in plasma. Direct deproteinization was first used to extract parent p-XSC from plasma, but failed to achieve high recovery rate (< 2%) due to formation of selenium-sulfur bond between p-XSC and plasma protein...
June 22, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28640201/deoxynivalenol-biomarkers-in-the-urine-of-uk-vegetarians
#15
Liz Wells, Laura Hardie, Courtney Williams, Kay White, Yunru Liu, Barbara De Santis, Francesca Debegnach, Georgio Moretti, Stephanie Greetham, Carlo Brera, Maria Papageorgiou, Natalie J Thatcher, Alan Rigby, Stephen L Atkin, Thozhukat Sathyapalan
Deoxynivalenol (DON) is produced by Fusarium graminearum and is one of the most commonly occurring trichothecenes. Vegetarians are alleged to be a high-risk group for DON exposure due to high intakes of cereals susceptible to the growth of the mycotoxin. This study provides the levels of DON and de-epoxi Deoxynivalenol (DOM-1) in urine analysed by liquid chromatography-mass spectrometry (LC-MS) in UK vegetarians. Over two consecutive days, morning urine samples were collected from 32 vegetarians and 31 UK adult volunteers, and associated food consumption 24 h prior to the sample was recorded...
June 22, 2017: Toxins
https://www.readbyqxmd.com/read/28640062/an-atmospheric-pressure-ionization-ms-ms-assay-using-online-extraction-for-the-analysis-of-11-cannabinoids-and-metabolites-in-human-plasma-and-urine
#16
Jelena Klawitter, Cristina Sempio, Sophie Mörlein, Erik De Bloois, Jacek Klepacki, Thomas Henthorn, Maureen A Leehey, Edward J Hoffenberg, Kelly Knupp, George S Wang, Christian Hopfer, Greg Kinney, Russell Bowler, Nicholas Foreman, Jeffrey Galinkin, Uwe Christians, Jost Klawitter
BACKGROUND: Although, especially in the United States, there has been a recent surge of legalized cannabis for either recreational or medicinal purposes, surprisingly little is known about clinical dose-response relationships, pharmaco- and toxicodynamic effects of cannabinoids such as Δ9-tetrahydrocannabinol (THC). Even less is known about other active cannabinoids. METHODS: To address this knowledge gap, an online extraction, high-performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) method for simultaneous quantification of 11 cannabinoids and metabolites including THC, 11-hydroxy-Δ9-tetrahydrocannabinol (11OH-THC), 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH), 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid glucuronide (THC-C-gluc), cannabinol (CBN), cannabidiol (CBD), cannabigerol (CBG), cannabidivarin (CBDV), Δ9-tetrahydrocannabivarin (THCV), and 11-nor-9-carboxy-Δ9-tetrahydrocannabivarin (THCV-COOH) was developed and validated in human urine and plasma...
June 19, 2017: Therapeutic Drug Monitoring
https://www.readbyqxmd.com/read/28639014/sediments-as-a-sink-for-uv-filters-and-benzotriazoles-the-case-study-of-upper-igua%C3%A3-u-watershed-curitiba-brazil
#17
Alinne Mizukawa, Daniel Molins-Delgado, Júlio César Rodrigues de Azevedo, Cristóvão Vicente Scapulatempo Fernandes, Silvia Díaz-Cruz, Damià Barceló
Ingredients in home and personal care products, including UV filters and benzotriazoles, are high production volume chemicals extensively used in our daily life, despite several studies revealed their potential eco-toxicity and endocrine-disrupting capacity. Due to some features, such as high lipophilicity, low degradability, and persistence of many of these compounds, sediments can be considered a sink for them in the aquatic environment. In the present study, nine organic UV filters and three benzotriazoles were investigated for the first time in sediments from four urban rivers in Brazil...
June 21, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28638306/effect-of-maternal-obesity-on-maternal-fetal-transfer-of-preoperative-cefazolin-at-cesarean-section
#18
Stephanie McKenney Groff, Wareef Fallatah, Samuel Yang, Jamie Murphy, Christopher Crutchfield, Mark Marzinke, Joanne Kurtzberg, Carlton K K Lee, Irina Burd, Azadeh Farzin
OBJECTIVES: American Congress of Obstetricians and Gynecologists recommends a single dose of antibiotic prophylaxis before all cesarean sections (C/S). This recommendation is based on pharmacokinetic studies that include only non-obese patients. We sought to evaluate 1) cefazolin plasma concentrations among obese and non-obese patients after administration of a 2-g cefazolin dose for prevention of surgical wound infections, and 2) whether cefazolin concentration in fetal circulation may be protective against pathogens that cause early onset neonatal sepsis...
May 2017: Journal of Pediatric Pharmacology and Therapeutics: JPPT: the Official Journal of PPAG
https://www.readbyqxmd.com/read/28638069/global-profiling-of-phytohormone-dynamics-during-combined-drought-and-pathogen-stress-in-arabidopsis-thaliana-reveals-aba-and-ja-as-major-regulators
#19
Aarti Gupta, Hiroshi Hisano, Yuko Hojo, Takakazu Matsuura, Yoko Ikeda, Izumi C Mori, Muthappa Senthil-Kumar
Global transcriptome studies demonstrated the existence of unique plant responses under combined stress which are otherwise not seen during individual stresses. In order to combat combined stress plants use signaling pathways and 'cross talk' mediated by hormones involved in stress and growth related processes. However, interactions among hormones' pathways in combined stressed plants are not yet known. Here we studied dynamics of different hormones under individual and combined drought and pathogen infection in Arabidopsis thaliana by liquid chromatography-mass spectrometry (LC-MS) based profiling...
June 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28637948/in-the-overnight-dexamethasone-suppression-test-1-0-mg-loading-is-superior-to-0-5-mg-loading-for-diagnosing-subclinical-adrenal-cushing-s-syndrome-based-on-plasma-dexamethasone-levels-determined-using-liquid-chromatography-tandem-mass-spectrometry
#20
Yosuke Sasaki, Takuyuki Katabami, Shiko Asai, Hisashi Fukuda, Yasushi Tanaka
The low-dose dexamethasone suppression test (DST) is one of the commonly used initial tests for endogenous Cushing's syndrome (CS). However, there are two loading dose regimens (0.5-mg and 1-mg), which may cause some confusion in daily practice in Japan; furthermore, there are no reports regarding whether 0.5-mg DST is a better loading dose for detecting adrenal subclinical CS (SCS) based on the plasma dexamethasone (DEX) levels. Therefore, the aims of this study were (a) to develop a novel assay to measure DEX by using liquid chromatography tandem-mass spectrometry (LC-MS/MS) and (b) to compare between the 0...
June 21, 2017: Endocrine Journal
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