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https://www.readbyqxmd.com/read/29227190/determination-of-propineb-and-its-metabolites-propylenethiourea-and-propylenediamine-in-banana-and-soil-using-gas-chromatography-with-flame-photometric-detection-and-lc-ms-ms-analysis
#1
Shiming Song, Jie Wei, Zhaojie Chen, Yuhao Lei, Yan Zhang, Cheng Deng, Huihua Tan, Xuesheng Li
A sensitive and specific method for the determination of propineb and its metabolites, propylenethiourea (PTU) and propylenediamine (PDA), using gas chromatography with flame photometric detection (GC-FPD) and LC-MS/MS was developed and validated. Propineb and its metabolite residue dynamics in supervised field trials under Good Agricultural Practice (GAP) conditions in banana and soil were studied. Recovery of propineb (as CS2), PDA and PTU ranged from 75.3 to 115.4% with RSD (n = 5) of 1.3-11.1%. The limit of quantification (LOQ) of CS2, PDA and PTU ranged from 0...
December 11, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/29226434/protein-identification-in-imaging-mass-spectrometry-through-spatially-targeted-liquid-micro-extractions
#2
Daniel J Ryan, David Nei, Boone M Prentice, Kristie L Rose, Richard M Caprioli, Jeffrey M Spraggins
RATIONALE: Liquid extraction surface analysis (LESA) can be used to generate spatially-directed protein identifications in an imaging mass spectrometry (IMS) workflow. This approach involves the use of robotic micro-extractions coupled to online liquid chromatography (LC). We have characterized the extraction efficiency of this method as well as its ability to identify proteins from a matrix assisted laser/desorption ionization (MALDI) IMS experiment. METHODS: Proteins and peptides were extracted from transverse sections of a rat brain and sagittal sections of a mouse pup using liquid surface extractions...
December 10, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/29226354/liquid-chromatographic-methods-for-the-therapeutic-drug-monitoring-of-methotrexate-as-clinical-decision-support-for-personalized-medicine-a-brief-review
#3
REVIEW
Mónica Francisco Silva, Cláudia Ribeiro, Virgínia M F Gonçalves, Maria Elizabeth Tiritan, Áurea Lima
Methotrexate (MTX) is an antifolate drug used for several diseases. Depending on the disease, MTX can be administered at low-dose (LDMTX) in some autoimmune diseases, like rheumatoid arthritis, or at high-dose (HDMTX) in some cancers, such as acute lymphoblastic leukaemia. After absorption, MTX is metabolized in the liver to 7-hydroxymethotrexate (7-OH-MTX) and in the intestine to 2,4-diamino-N10-methylpteroic acid (DAMPA). Moreover, inside red blood cells (RBCs), MTX is converted to active metabolites, MTX polyglutamates (MTXPGs), contributing to its pharmacodynamics...
December 11, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29225777/evaluation-of-electrochemiluminescence-immunoassays-for-immunosuppressive-drugs-on-the-roche-cobas-e411-analyzer
#4
Angela W S Fung, Michael J Knauer, Ivan M Blasutig, David A Colantonio, Vathany Kulasingam
Background:  Therapeutic drug monitoring of immunosuppressant drugs are used to monitor drug efficacy and toxicity and to prevent organ transplantation rejection. This study evaluates the analytical performance of semi-automated electrochemiluminescence immunoassays (ECLIA) for cyclosporine (CSA), tacrolimus (TAC) and sirolimus (SRL) on the Roche cobas e 411 analyzer at a major transplant hospital to identify method suitability and limitations. Methods: Residual whole blood samples from patients undergoing immunosuppressant therapy were used for evaluation...
2017: F1000Research
https://www.readbyqxmd.com/read/29225663/high-throughput-detection-of-antioxidants-in-mulberry-fruit-using-correlations-between-high-resolution-mass-and-activity-profiles-of-chromatographic-fractions
#5
Ye Ji Park, Si Hyun Seong, Min Sun Kim, Sang Wan Seo, Mee Ree Kim, Hyun Sik Kim
Background: Plant extracts contain a huge variety of pharmacologically active substances. Conventionally, various chromatographic methods must be applied several times to purify functional compounds to measure their functional activity. However, conventional purification methods are time-consuming and expensive due to the laborious purification process. Recently, a high-throughput discovery method that replaces such time-consuming purification processes was introduced; this method uses 15 T ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry (15 T FT-ICR MS) and a high-throughput screening method...
2017: Plant Methods
https://www.readbyqxmd.com/read/29225558/vulvar-squamous-cell-carcinoma-aggressiveness-is-associated-with-differential-expression-of-collagen-and-stat1
#6
Emily R Holthoff, Stephanie D Byrum, Samuel G Mackintosh, Thomas Kelly, Alan J Tackett, Charles M Quick, Steven R Post
Background: Vulvar squamous cell carcinoma (vSCC) is a rare but debilitating disease. One vSCC variant comprises tumor cells that grow and expand as a cohesive sheet of cells that "pushes" and compresses the associated lymphoplasmacytic (LPC) stroma. Another vSCC variant features tumor cells that grow in loose association with one another and infiltrate the associated fibromyxoid (FMX) stroma consisting mainly of extracellular matrix. Clinically, infiltrative vSCC with FMX stroma (Inf/FMX) is significantly associated with lymph node metastases and recurrence...
2017: Clinical Proteomics
https://www.readbyqxmd.com/read/29224354/high-speed-counter-current-chromatography-hsccc-purification-of-antifungal-fatty-acids-from-plant-seed-oil-and-lactobacillus-fermentation
#7
Nuan Yi Liang, Pengfei Cai, Datong Wu, Yuanjiang Pan, Jonathan M Curtis, Michael G Gänzle
Hydroxy unsaturated fatty acids (HUFA) can function as antifungal agents. To investigate the antifungal spectrum, i.e. the scope of in vitro fungal inhibition activities of HUFA and their potential applications, three HUFA were produced by microbial transformation or extracted from plant seed oils; compounds included coriolic acid (13-hydroxy-9,11-octadecadienoic acid) from Coriaria seed oil, 10-hydroxy-12-octadecenoic acid from cultures of Lactobacillus hammesii and 13-hydroxy-9-octadecenoic acid from cultures of Lactobacillus plantarum TMW1...
December 10, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29224348/stereoselective-total-synthesis-of-macrophage-produced-prohealing-14-21-dihydroxydocosahexaenoic-acids
#8
Keita Nishimura, Tsuyoshi Sakaguchi, Yutaro Nanba, Yuta Suganuma, Masao Morita, Song Hong, Yan Lu, Bokkyoo Jun, Nicolas G Bazan, Makoto Arita, Yuichi Kobayashi
Synthesis of 14S,21R- and 14S,21S-dihydroxy-DHA (diHDHA) among the four possible stereoisomers of 14,21-diHDHA was studied. Methyl (R)-lactate (>97% ee), selected as a C20-C22 fragment (DHA numbering), was converted to the C17-C22 phosphonium salt, which was subjected to a Wittig reaction with racemic C16-aldehyde of the C12-C16 part with the TMS and TBS-oxy groups at C12 and C14, yielding the C12-C22 derivative with 14R/S and 21R chirality. Kinetic resolution using Sharpless asymmetric epoxidation of the TBS-deprotected allylic alcohol with L-(+)-DIPT/Ti(O-i-Pr)4 afforded 14S-epoxy alcohol and 14R-allylic alcohol with >99% diastereomeric excess (de) for both...
December 11, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/29223892/liquid-chromatography-quadrupole-time-of-flight-mass-spectrometry-determination-of-six-pharmaceuticals-in-vegetal-biota-uptake-study-in-lavandula-dentata
#9
Sofía Barreales-Suárez, Manuel Callejón-Mochón, Stéphane Azoulay, Miguel Ángel Bello-López, Rut Fernández-Torres
A procedure based on microwave assisted extraction for the determination of 6 pharmaceuticals in samples of Lavandula dentata, Salicornia ramosissima and Juncus sp. by liquid chromatography-quadrupole time of flight mass spectrometry (LC-QTOF/MS) was optimized and validated. Best results were obtained using microwave assisted extraction of 1.0g of homogeneous lyophilized samples and 5mL of a mixture ACN:H2O (1:1 v/v) as extracting solvent. Analytical recoveries ranged from 60 to 107% with relative standard deviation (RSD) lower than 15%...
December 6, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29223786/the-eukaryotic-translation-initiation-factor-3-subunit-e-binds-to-classical-swine-fever-virus-ns5a-and-facilitates-viral-replication
#10
Xiaofeng Liu, Xiaoyu Wang, Qian Wang, Mingyang Luo, Huancheng Guo, Wenjie Gong, Changchun Tu, Jinfu Sun
Classical swine fever virus (CSFV) NS5A protein is a multifunctional protein, playing critical roles in viral RNA replication, translation and assembly. To further explore its functions in viral replication, interaction of NS5A with host factors was assayed using a his-tag "pull down" assay coupled with shotgun LC-MS/MS. Host protein translation initiation factor 3 subunit E was identified as a binding partner of NS5A, and confirmed by co-immunoprecipitation and co-localization analysis. Overexpression of eIF3E markedly enhanced CSFV genomic replication, viral protein expression and production of progeny virus, and downregulation of eIF3E by siRNA significantly decreased viral proliferation in PK-15 cells...
December 7, 2017: Virology
https://www.readbyqxmd.com/read/29223716/alkaline-degradation-of-lyophilized-dmsa-prior-to-labeling-with-99mtc-identification-and-development-of-the-degradation-pathway-by-hplc-and-ms
#11
Erika V Almeida, Samuel L De Brito
INTRODUCTION: Complexes of technetium-99m (99mTc) with meso-dimercaptosuccinic acid (DMSA) have been widely used as diagnostic agents in nuclear medicine. The degradation products (DP) of DMSA formed under different forced conditions have been identified through HPLC-DAD and LC-MSn studies. In this study, the DMSA kit was subjected to forced degradation under hydrolysis conditions as prescribed by the International Conference on Harmonization (ICH) guideline Q1A. METHODS: Chromatographic separation was accomplished on a reverse phase Shim-Pack VP-ODS (150 mm × 4...
November 10, 2017: Nuclear Medicine and Biology
https://www.readbyqxmd.com/read/29223552/caffeine-rich-infusion-from-cola-nitida-kola-nut-inhibits-major-carbohydrate-catabolic-enzymes-abates-redox-imbalance-and-modulates-oxidative-dysregulated-metabolic-pathways-and-metabolites-in-fe2-induced-hepatic-toxicity
#12
Ochuko L Erukainure, Olajumoke A Oyebode, Mxolisi K Sokhela, Neil A Koorbanally, Md Shahidul Islam
The antioxidative and antidiabetic effects and toxicity of caffeine-rich infusion of Cola nitida were investigated using in vitro, ex vivo and in silico models. C. nitida was infused in boiling water and allowed to cool before concentrating at <50°C. HPLC analysis of the infusion revealed a caffeine content of 80.08%. The infusion showed potent in vitro antioxidant activity by significantly (p<0.05) scavenging 2,2'-diphenyl-1-picrylhydrazyl (DPPH). It significantly (p<0.05) inhibited α-glucosidase and α-amylase activities...
December 6, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/29223322/systemic-administration-of-epothilone-d-improves-functional-recovery-of-walking-after-rat-spinal-cord-contusion-injury
#13
Jörg Ruschel, Frank Bradke
Central nervous system (CNS) injuries cause permanent impairments of sensorimotor functions as mature neurons fail to regenerate their severed axons. The poor intrinsic growth capacity of adult CNS neurons and the formation of an inhibitory lesion scar are key impediments to axon regeneration. Systemic administration of the microtubule stabilizing agent epothilone B promotes axon regeneration and recovery of motor function by activating the intrinsic axonal growth machinery and by reducing the inhibitory fibrotic lesion scar...
December 6, 2017: Experimental Neurology
https://www.readbyqxmd.com/read/29223071/bioactive-potential-of-silica-coatings-and-its-effect-on-the-adhesion-of-proteins-to-titanium-implants
#14
F Romero-Gavilan, N Araújo-Gomes, A M Sánchez-Pérez, I García-Arnáez, F Elortza, M Azkargorta, J J Martín de Llano, C Carda, M Gurruchaga, J Suay, I Goñi
There is an ever-increasing need to develop dental implants with ideal characteristics to achieve specific and desired biological response in the scope of improve the healing process post-implantation. Following that premise, enhancing and optimizing titanium implants through superficial treatments, like silica sol-gel hybrid coatings, are regarded as a route of future research in this area. These coatings change the physicochemical properties of the implant, ultimately affecting its biological characteristics...
December 6, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/29223062/hplc-ms-ms-method-optimisation-for-matrix-metalloproteinase-3-and-matrix-metalloproteinase-9-determination-in-human-blood-serum-using-target-analysis
#15
Petra Kotnik, Metka Koren Krajnc, Artur Pahor, Matjaž Finšgar, Željko Knez
A quantitative analysis of zinc endopeptidases matrix metalloproteinase 9 (MMP9) and matrix metalloproteinase 3 (MMP3) from human blood serum are presented. Both matrix metalloproteinases (MMP) are present in human blood serum and can be used as biomarkers for different diseases. The analysis was performed using LC-MS/MS with a triple quadrupole mass spectrometer, based on two specific peptides of each MMP in comparison with an enzyme-linked immunosorbent assay (ELISA). While the conditions for the LC-MS/MS analysis of MMP9 peptides were previously reported for bronchoalveolar lavage fluid, the analysis of MMP3 peptides was newly quantified for human blood serum herein for the first time...
November 29, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29223061/impurity-profiling-of-n-n-ethylenebis-l-cysteine-diethyl-ester-bicisate
#16
Oliver Wahl, Jan Cleynhens, Alfons M Verbruggen, Ulrike Holzgrabe
A HPLC-UV-CAD method with a HILIC column for impurity profiling of the 99mTc chelating agent bicisate has been developed and evaluated. Bicisate and its impurities were separated by means of isocratic elution on a zwitterionic stationary phase using a mixture of 7.5mmol/L trifluoroacetic acid and acetonitrile (47.5:52.5 V/V) as the mobile phase. Five different bicisate batches of a manufacturer were tested using the method. In addition LC-MS experiments were conducted in order to identify the impurities. The predominant impurities found were the oxidation product (disulfide), the monoester of ethylene dicysteine and an unknown compound with an m/z of 293 in ESI positive mode...
December 5, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29223050/a-simple-rapid-and-stability-indicating-validated-method-for-quantification-of-lamotrigine-in-human-plasma-and-dry-plasma-spot-using-lc-esi-ms-ms-application-in-clinical-study
#17
Kuldeep Kumar Namdev, Jaya Dwivedi, Deepak Chandra Chilkoti, Swapnil Sharma
Lamotrigine (LTZ) is a phenyltriazine derivative which belongs to anti-epileptic drugs (AEDs) class and prescribed as mono- or adjunctive-therapy in treatment of epilepsy. Therapeutic drug monitoring (TDM) of AEDs provides a valid clinical tool in optimization of overall therapy. However, TDM is challenging due to the high biological samples (plasma/blood) storage/shipment costs and the limited availability of laboratories providing TDM services. Sampling in the form of dry plasma spot (DPS) or dry blood spot (DBS) are suitable alternative to overcome these issues...
December 1, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29223047/identification-and-analysis-of-a-mercapturic-acid-conjugate-of-indole-3-methyl-isothiocyanate-in-the-urine-of-humans-who-consumed-cruciferous-vegetables
#18
Pramod Upadhyaya, Adam T Zarth, Naomi Fujioka, Vincent A Fritz, Stephen S Hecht
Glucobrassicin, a quantitatively significant constituent of Brassica vegetables, gives rise to indole-3-carbinol (I3C) and its dimer di-indolylmethane (DIM) when the vegetables are chewed. I3C and DIM have been extensively studied with respect to their anti-carcinogenic properties. However, the presumed intermediate isothiocyanate in their formation, indole-3-methyl isothiocyanate (IMITC), has to our knowledge never been observed, despite the fact that isothiocyanates derived from cruciferous vegetables are known to have anti-carcinogenic properties...
December 2, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29222903/vitamin-d-status-and-cardiometabolic-risk-factors-in-young-adults-in-hong-kong-associations-and-implications
#19
Erica Wei-Lan Wang, Marco Yiu-Chung Pang, Parco Ming-Fai Siu, Claudia Kam-Yuk Lai, Jean Woo, Andrew R Collins, Iris Ff Benzie
BACKGROUND AND OBJECTIVES: Vitamin D deficiency is reportedly common, but we lack data from young adults. Such data are of interest because epidemiological data support vitamin D as a possible risk modulator for diabetes and cardiovascular ('cardiometabolic') disease. Our objectives were to assess vitamin D status (as plasma 25(OH)D concentration) and investigate associations between this and biomarkers of cardiometabolic disease risk in a group of still-healthy young adults in Hong Kong...
2018: Asia Pacific Journal of Clinical Nutrition
https://www.readbyqxmd.com/read/29222052/in-vitro-co-culture-models-to-evaluate-acute-cytotoxicity-of-individual-and-combined-mycotoxin-exposures-on-caco-2-thp-1-and-heparg-human-cell-lines
#20
Marie-Caroline Smith, Alexiane Gheux, Monika Coton, Stéphanie Madec, Nolwenn Hymery, Emmanuel Coton
Deoxynivalenol (DON) and zearalenone (ZEA) are mycotoxins primarily produced by Fusarium species and commonly co-occur in European grains. Some in vitro studies reported synergistic combined effects on cell viability reduction for these two natural food contaminants. However, most of these studies were carried out on conventional cell culture systems involving only one cell type and thus, did not accurately reflect in vivo conditions, including cell-cell communication. In this context, we developed easy bi- and tri-culture systems using the Caco-2 (intestinal epithelial cells), THP-1 (monocytes) and HepaRG (hepatocytes) human cell lines...
December 5, 2017: Chemico-biological Interactions
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