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https://www.readbyqxmd.com/read/28922661/lysophosphatidic-acid-inhibits-insulin-signaling-in-primary-rat-hepatocytes-via-the-lpa3-receptor-subtype-and-is-increased-in-obesity
#1
Susann Fayyaz, Lukasz Japtok, Fabian Schumacher, Dominik Wigger, Tim Julius Schulz, Kathrin Haubold, Erich Gulbins, Heinz Völler, Burkhard Kleuser
BACKGROUND/AIMS: Obesity is a main risk factor for the development of hepatic insulin resistance and it is accompanied by adipocyte hypertrophy and an elevated expression of different adipokines such as autotaxin (ATX). ATX converts lysophosphatidylcholine to lysophosphatidic acid (LPA) and acts as the main producer of extracellular LPA. This bioactive lipid regulates a broad range of physiological and pathological responses by activation of LPA receptors (LPA1-6). METHODS: The activation of phosphatidylinositide 3-kinases (PI3K) signaling (Akt and GSK-3ß) was analyzed via western blotting in primary rat hepatocytes...
September 1, 2017: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/28922649/determination-of-74-new-psychoactive-substances-in-serum-using-automated-in-line-solid-phase-extraction-liquid-chromatography-tandem-mass-spectrometry
#2
Sabrina Lehmann, Tobias Kieliba, Justus Beike, Mario Thevis, Katja Mercer-Chalmers-Bender
A detailed description is given of the development and validation of a fully automated in-line solid-phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) method capable of detecting 90 central-stimulating new psychoactive substances (NPS) and 5 conventional amphetamine-type stimulants (amphetamine, 3,4-methylenedioxy-methamphetamine (MDMA), 3,4-methylenedioxy-amphetamine (MDA), 3,4-methylenedioxy-N-ethyl-amphetamine (MDEA), methamphetamine) in serum. The aim was to apply the validated method to forensic samples...
September 7, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28922623/development-of-in-house-elisa-for-detection-of-chloramphenicol-in-bovine-milk-with-subsequent-confirmatory-analysis-by-lc-ms-ms
#3
Muhammad I Chughtai, Uzma Maqbool, Mazhar Iqbal, Muhammad S Shah, Terence Fodey
This study was undertaken to develop and validate direct competitive ELISA for the determination of chloramphenicol residues in bovine milk. Antisera and an enzyme-tracer for chloramphenicol were prepared and used to develop an ELISA with inhibition concentrations, IC20 and IC50, of 0.09 and 0.44 ng mL(-1), respectively. Milk samples were spiked with standards equivalent to 0, 0.2, 0.3, 0.5, 1.0 & 1.5 ng mL(-1) and extracted in methanol. The mean recoveries were found to be 73-100% with coefficient of variance 7-11%...
September 18, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/28921945/multiwalled-carbon-nanotubes-dramatically-affect-the-fruit-metabolome-of-exposed-tomato-plants
#4
Diamond L McGehee, Mohamed H Lahiani, Fahmida Irin, Micah J Green, Mariya V Khodakovskaya
Here, we reported that multiwalled carbon nanotubes (MWCNT) added to hydroponics system can enhance fruit production of exposed tomato plants. We quantified the exact amount of MWCNT accumulated inside of fruits collected by MWCNT-exposed plants using an advanced microwave induced heating technique (MIH). We found that absorption of MWCNT by tomato fruits significantly affected total fruit metabolome as was confirmed by LC-MS. Our data highlight the importance of comprehensive toxicological risk assessment of plants contaminated with carbon nanomaterials...
September 18, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28921680/measurement-of-urinary-concentrations-of-the-mycotoxins-zearalenone-and-sterigmatocystin-as-biomarkers-of-exposure-in%C3%A2-mares
#5
M Takagi, S Uno, E Kokushi, F Sato, Mmp Wijayagunawardane, J Fink-Gremmels
Mycotoxins may affect animal health, including reproduction. Little is known about the clinical relevance of exposure of horses to contaminated feed. This study aimed at (i) monitoring the levels of the mycotoxins zearalenone (ZEN), with its metabolites α- and β-zearalenol (α- and β-ZOL), and sterigmatocystin (STC) in urine samples from thoroughbred mares in Japan and (ii) relating these findings to the potential effects on reproductive efficacy of breeding mares. Sixty-three urine samples of breeding mares from 59 breeding farms were used...
September 18, 2017: Reproduction in Domestic Animals, Zuchthygiene
https://www.readbyqxmd.com/read/28921388/immunomodulatory-potential-of-nanocurcumin-based-formulation
#6
Mahendra Kumar Trivedi, Sambhu Charan Mondal, Mayank Gangwar, Snehasis Jana
Vitamins, minerals, and nanocurcumin play a substantial role in various nutraceutical/pharmaceutical formulations that are widely used in therapeutics, cosmetics, and dietary supplements. The current study aimed to investigate the comparative in vitro immunomodulatory effect of a novel nanocurcumin-based formulation with curcumin in LPS-induced cytokine expression, NK cells' activity, and phagocytosis. The proinflammatory cytokines (TNF-α, IL-1β, and MIP-1α) and NK cells' activity were measured in cell supernatants using ELISA assay; however, phagocytosis activity was performed using colorimetric analysis...
September 18, 2017: Inflammopharmacology
https://www.readbyqxmd.com/read/28920454/investigation-of-o-glycosylation-heterogeneity-of-recombinant-coagulation-factor-ix-using-lc-ms-ms
#7
Youngsuk Seo, Gyeong Mi Park, Myung Jin Oh, Hyun Joo An
AIM: Recombinant coagulation factor IX (rFIX) has extraordinarily multiple post-translational modifications including N-glycosylation and O-glycosylation which have a drastic effect on biological functions and in vivo recovery. Unlike N-glycosylation extensively characterized, there are a few studies on O-glycosylation due to its intrinsic complexity. In-depth O-glycosylation analysis is necessary to better understand and assess pharmacological activity of rFIX. RESULTS: We determined unusual O-glycosylations including O-fucosylation and O-glucosylation which were located at Serine 53 and 61, respectively in EGF domain...
September 18, 2017: Bioanalysis
https://www.readbyqxmd.com/read/28920446/key-considerations-for-lc-ms-analysis-of-protein-biotherapeutics-in-tissues
#8
Wei Fu, Bo An, Xue Wang, Jun Qu
No abstract text is available yet for this article.
September 18, 2017: Bioanalysis
https://www.readbyqxmd.com/read/28919509/molecular-and-macro-scale-analysis-of-enzyme-crosslinked-silk-hydrogels-for-rational-biomaterial-design
#9
Meghan McGill, Jeannine M Coburn, Benjamin P Partlow, Xuan Mu, David L Kaplan
Silk fibroin-based hydrogels have exciting applications in tissue engineering and therapeutic molecule delivery; however, their utility is dependent on their diffusive properties. The present study describes a molecular and macro-scale investigation of enzymatically-crosslinked silk fibroin hydrogels, and demonstrates that these systems have tunable crosslink density and diffusivity. We developed a liquid chromatography tandem mass spectroscopy (LC-MS/MS) method to assess the quantity and order of covalent tyrosine crosslinks in the hydrogels...
September 14, 2017: Acta Biomaterialia
https://www.readbyqxmd.com/read/28919422/over-expression-of-ppar%C3%AE-in-obese-mice-adipose-tissue-improves-insulin-sensitivity
#10
Haruya Takahashi, Kohei Sanada, Hiroyuki Nagai, Yongjia Li, Yumeko Aoki, Takeshi Ara, Shigeto Seno, Hideo Matsuda, Rina Yu, Teruo Kawada, Tsuyoshi Goto
Peroxisome proliferator-activated receptor α (PPARα) is important in the regulation of lipid metabolism and expressed at high levels in the liver. Although PPARα is also expressed in adipose tissue, little is known about the relationship between its activation and the regulation of glucose metabolism. In this study, we developed adipose tissue specific PPARα over-expression (OE) mice. Metabolomics and insulin tolerance tests showed that OE induces branched-chain amino acid (BCAA) profile and improvement of insulin sensitivity...
September 15, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28918593/decline-patterns-and-risk-assessment-of-10-multi-class-pesticides-in-young-sprout-amaranth-amaranthus-mangostanus-under-greenhouse-growing-conditions
#11
In Kyung Kim, Sung-Woo Kim, A M Abd El-Aty, Md Musfiqur Rahman, Md Humayun Kabir, Han Sol Lee, Hyung Suk Chung, Ji Hoon Jeong, Ho-Chul Shin, Jae-Han Shim
The present study was designed to investigate the residual decline pattern and the risk assessment of 10 different class pesticides, namely azoxystrobin, boscalid, diazinon, diethofencarb, difenoconazole, etofenprox, flubendiamide, paclobutrazol, and pyraclostrobin in young vegetative amaranth (Amaranthus mangostanus) sprayed once or twice under greenhouse growing conditions. Field-incurred samples, collected at 3, 7, or 10 days after application of both treatments, were extracted and purified with the quick, easy, cheap, effective, rugged, and safe "QuEChERS" citrate-buffered method and analyzed with liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS) in positive ion mode...
September 16, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28918326/a-surrogate-analyte-based-liquid-chromatography-tandem-mass-spectrometry-method-for-the-determination-of-endogenous-cyclic-nucleotides-in-rat-brain
#12
Jie Chen, Ali Tabatabaei, Doug Zook, Yan Wang, Anne Danks, Kathe Stauber
A robust high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) assay was developed and qualified for the measurement of cyclic nucleotides (cNTs) in rat brain tissue. Stable isotopically labeled 3',5'-cyclic adenosine-(13)C5 monophosphate ((13)C5-cAMP) and 3',5'-cyclic guanosine-(13)C,(15)N2 monophosphate ((13)C(15)N2-cGMP) were used as surrogate analytes to measure endogenous 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP). Pre-weighed frozen rat brain samples were rapidly homogenized in 0...
September 14, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28918325/a-novel-lc-ms-ms-method-for-the-quantitative-measurement-of-the-acetate-content-in-pharmaceutical-peptides
#13
Rani J Qasem, Ibrahim K Farh, Mohammed A Al Essa
Most pharmaceutical peptides are supplied as acetate salts and the relative amount of acetate to peptide in the final product is one quality criterion required by regulatory agencies to approve the product for clinical use. The objective of the present study was to develop a validated LC-MS/MS method that allows the quantitative determination of the acetate content in pharmaceutical peptide preparations and simultaneous monitoring and collection of qualitative and quantitative information on the peptide during manufacture and in the final product...
September 6, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28918323/quantitative-determination-of-carfilzomib-in-mouse-plasma-by-liquid-chromatography-tandem-mass-spectrometry-and-its-application-to-a-pharmacokinetic-study
#14
Jee Sun Min, Jiseon Kim, Jung Ho Kim, Doyun Kim, Yu Fen Zheng, Ji Eun Park, Wooin Lee, Soo Kyung Bae
A highly sensitive and rapid LC-MS/MS method was developed and validated to determine the levels of carfilzomib in mice plasma by using chlorpropamide as an internal standard. Carfilzomib and chlorpropamide were extracted from 5 μL of plasma after protein precipitation with acetonitrile. Chromatographic separation was performed on Phenomenex Luna C18 column (50×2.0mm id, 3μm). The mobile phase consisted of 0.1% formic acid in acetonitrile -0.1% formic acid in water (1:1v/v) and the flow rate was 0.3mL/min...
September 1, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28918318/high-sensitivity-method-validated-to-quantify-estradiol-in-human-plasma-by-lc-ms-ms
#15
Mônica Siqueira Ferreira, André M M Arruda, Giovanni Tieghi Pepi, Aline Cristina Martho, Pâmela Maria Maximiano, Lina S O B O Ricci, Maria Francesca Riccio, Ana Cláudia Noboli, Pedro Serafim
17β-Estradiol (E2) is an endogenous steroid in the human body. Its measurement is important for health and human biology understanding. However, E2 concentration in human plasma is in the range of pg/mL, which makes it difficult to detect. In this way, LC-MS/MS has been shown the most sensitive tool, although E2 is a weakly ionizable molecule. In this work, we validated a more sensitive and accurate method for E2 quantification in human plasma. Our extraction step ensured a cleaner chromatography, resulting in a precise measurement and highly reproducible method in the range of 2-150pg/mL...
September 5, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28918279/seasonal-variation-of-chloro-s-triazines-in-the-hartbeespoort-dam-catchment-south-africa
#16
Cornelius Rimayi, David Odusanya, Jana M Weiss, Jacob de Boer, Luke Chimuka
Seasonal variation of eight chloro-s-triazine herbicides and seven major atrazine and terbuthylazine degradation products was monitored in the Hartbeespoort Dam catchment using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS/MS). Lake, river and groundwater were sampled from the Hartbeespoort Dam catchment over four seasons and the downstream Jukskei River was monitored during the winter season. Triazine herbicide concentrations in the Hartbeespoort Dam were in the order atrazine>simazine>propazine>ametryn>prometryn throughout the four seasons sampled...
September 14, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28917861/isolation-and-structural-elucidation-by-2d-nmr-of-planteose-a-major-oligosaccharide-in-the-mucilage-of-chia-salvia-hispanica-l-seeds
#17
Xiaohui Xing, Yves S Y Hsieh, Kuok Yap, Main E Ang, Jelle Lahnstein, Matthew R Tucker, Rachel A Burton, Vincent Bulone
An oligosaccharide was isolated in high purity and excellent yield from the water-extractable mucilage of chia (Salvia hispanica L.) seeds using an optimized solid-phase extraction method. LC-MS analysis showed that the compound presents a molecular mass of 504Da and trifluoroacetic acid hydrolysis revealed that it consists of galactose, glucose and fructose. Glycosidic linkage analysis showed that the oligosaccharide contains two non-reducing ends corresponding to terminal glucopyranose and terminal galactopyranose, respectively...
November 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28917804/development-and-validation-of-a-maleimide-based-enzyme-linked-immunosorbent-assay-for-the-detection-of-tetrodotoxin-in-oysters-and-mussels
#18
Laia Reverté, Maria Rambla-Alegre, Sandra Leonardo, Carlos Bellés, Katrina Campbell, Christopher T Elliott, Arjen Gerssen, Mirjam D Klijnstra, Jorge Diogène, Mònica Campàs
The recent detection of tetrodotoxins (TTXs) in puffer fish and shellfish in Europe highlights the necessity to monitor the levels of TTXs in seafood by rapid, specific, sensitive and reliable methods in order to protect human consumers. A previous immunoassay for TTX detection in puffer fish, based on the use of self-assembled monolayers (SAMs) for the immobilization of TTX on maleimide plates (mELISA), has been modified and adapted to the analysis of oyster and mussel samples. Changing dithiol for cysteamine-based SAMs enabled reductions in the assay time and cost, while maintaining the sensitivity of the assay...
January 1, 2018: Talanta
https://www.readbyqxmd.com/read/28917762/full-validation-of-a-method-for-the-determination-of-drugs-of-abuse-in-non-mineralized-dental-biofilm-using-liquid-chromatography-tandem-mass-spectrometry-and-application-to-postmortem-samples
#19
Kerstin Henkel, Markus J Altenburger, Volker Auwärter, Merja A Neukamm
Alternative matrices play a major role in postmortem forensic toxicology, especially if common matrices (like body fluids or hair) are not available. Incorporation of illicit and medicinal drugs into non-mineralized dental biofilm (plaque) seems likely but has not been investigated so far. Analysis of plaque could therefore extend the spectrum of potentially used matrices in postmortem toxicology. For this reason, a rapid, simple and sensitive method for the extraction, determination and quantification of ten drugs of abuse from plaque using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and fully validated...
January 1, 2018: Talanta
https://www.readbyqxmd.com/read/28917754/quantification-of-7-aminoflunitrazepam-in-human-urine-by-polymeric-monolith-based-capillary-liquid-chromatography-coupled-to-tandem-mass-spectrometry
#20
Yu-Ru Wu, Hsiang-Yu Liu, Shu-Ling Lin, Ming-Ren Fuh
Using a simple liquid-liquid extraction (LLE) procedure for sample pretreatment, 7-Aminoflunitrazepam (7-aminoFM2), a major metabolite of flunitrazepam (FM2), was determined in urine samples by polymeric monolith-based capillary liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The linearity was found in the range of 0.1-50ngmL(-1) with a method detection limit (signal-to-noise ratio of 3) estimated at 0.05ngmL(-1). Using the proposed method, good precision and recovery were also found in spiked urine samples at the levels of 0...
January 1, 2018: Talanta
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