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https://www.readbyqxmd.com/read/29351237/bioengineering-of-rfviia-biopharmaceutical-and-structure-characterization-for-biosimilarity-assessment
#1
Othman Montacir, Houda Montacir, Murat Eravci, Andreas Springer, Stephan Hinderlich, Fereidoun Mahboudi, Amirhossein Saadati, Maria Kristina Parr
Eptacog alfa (NovoSeven®) is a vitamin K-dependent recombinant Factor VIIa produced by genetic engineering from baby hamster kidney (BHK) cells as a single peptide chain of 406 residues. After activation, it consists of a light chain (LC) of 152 amino and a heavy chain (HC) of 254 amino acids. Recombinant FVIIa undergoes many post-translational modifications (PTMs). The first ten glutamic acids of the N-terminal moiety are γ-carboxylated, Asn145 and Asn322 are N-glycosylated, and Ser52 and Ser60 are O-glycosylated...
January 19, 2018: Bioengineering
https://www.readbyqxmd.com/read/29350472/the-chemistry-and-pharmacology-of-synthetic-cannabinoid-sdb-006-and-its-regioisomeric-fluorinated-and-methoxylated-analogues
#2
Samuel D Banister, Alexander Olson, Matthew Winchester, Jordyn Stuart, Amelia R Edington, Richard C Kevin, Mitchell Longworth, Marco Herrera, Mark Connor, Iain S McGregor, Roy R Gerona, Michael Kassiou
Synthetic cannabinoids are the largest and most structurally diverse class of new psychoactive substances, with manufacturers often using isomerism to evade detection and circumvent legal restriction. The regioisomeric methoxy- and fluorine-substituted analogues of SDB-006 (N-benzyl-1-pentyl-1H-indole-3-carboxamide) were synthesized and could not be differentiated by gas chromatography-mass spectrometry (GC-MS), but were distinguishable by liquid chromatography-quadrupole time-of-flight-MS (LC-QTOF-MS). In a fluorescence-based plate reader membrane potential assay, SDB-006 acted as a potent agonist at human cannabinoid receptors (CB1 EC50 = 19 nM)...
January 19, 2018: Drug Testing and Analysis
https://www.readbyqxmd.com/read/29344587/an-exploratory-study-of-red-raspberry-rubus-idaeus-l-poly-phenols-metabolites-in-human-biological-samples
#3
Xuhuiqun Zhang, Amandeep Sandhu, Indika Edirisinghe, Britt Burton-Freeman
Red raspberry (Rubus idaeus L.) contains a variety of polyphenols including anthocyanins and ellagitannins. Red raspberry polyphenols absorbed in different forms (parent compounds, degradants or microbial metabolites) are subject to xenobiotic metabolism in the intestine, liver, and/or kidney, forming methylate, glucuronide, and sulfate conjugated metabolites. Upon acute exposure, (poly)phenol/metabolite presence in the blood depends mainly on intestinal absorption, enterohepatic circulation, and metabolism by resident microbiota...
January 18, 2018: Food & Function
https://www.readbyqxmd.com/read/29336082/metabolomics-study-of-cultivated-bulbus-fritillariae-cirrhosae-at-different-growth-stages-using-uhplc-qtof-ms-coupled-with-multivariate-data-analysis
#4
Zhao Geng, YiFei Liu, Yan Gou, QinMei Zhou, ChengJun He, Li Guo, Juan Zhou, Liang Xiong
INTRODUCTION: Bulbus fritillariae cirrhosae (known as Chuān bèi mǔ in China, BFC) contain fritillaria steroidal alkaloids as the bioactive ingredients and are widely used as traditional Chinese medicine for the treatment of cough and phlegm. Due to limited wild resources, the cultivated species are becoming predominantly used in Chinese traditional medicine markets. OBJECTIVE: To assess the impact of different growth stages on the alkaloids of cultivated BFC and establish a reference for quality control and guidance for appropriate harvesting practices...
January 15, 2018: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/29334653/depletion-study-withdrawal-period-calculation-and-bioaccumulation-of-sulfamethazine-in-tilapia-oreochromis-niloticus-treated-with-medicated-feed
#5
Kátia S D Nunes, José H Vallim, Márcia R Assalin, Sonia C N Queiroz, Lourival C Paraíba, Claudio M Jonsson, Felix G R Reyes
The residue depletion of sulfamethazine (SMZ) was evaluated in tilapia (Oreochromis niloticus) after 11 days of administration of medicated feed containing SMZ, at the dose of 422 mg/kg body weight (bw). The determination of SMZ in feed and tilapia fillet was carried out using the QuEChERS approach for sample preparation, and high performance liquid chromatography with diode array detector (HPLC-DAD) and ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS) for quantitation, respectively...
January 9, 2018: Chemosphere
https://www.readbyqxmd.com/read/29333858/mineral-and-base-catalyzed-hydrolysis-of-organophosphate-flame-retardants-a-potential-major-fate-controlling-sink-in-soil-and-aquatic-environments
#6
Yida Fang, Erin Kim, Timothy J Strathmann
The ubiquitous occurrence of organophosphate flame retardants (OPFRs) in aquatic and soil environments poses significant risks to human health and ecosystems. Here, we report on the hydrolysis of six OPFRs and three structural analogues in the absence and presence of metal (hydr)oxide minerals. Eight of the target compounds showed marked degradation in alkaline solutions (pH 9-12) with half-lives ranging from 0.02 - 170 d. Kinetics follow a second-order rate law with apparent rate constants for base-catalyzed hydrolysis (kB) ranging from 0...
January 15, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/29329431/a-validated-method-for-the-screening-of-320-forensically-significant-compounds-in-blood-by-lc-qtof-with-simultaneous-quantification-of-selected-compounds
#7
Emma Partridge, Stephen Trobbiani, Peter Stockham, Timothy Scott, Chris Kostakis
A broad drug screening method for toxicologically significant drugs and metabolites in whole blood using liquid chromatography time-of-flight mass spectrometry (LC/QTOF) was developed and comprehensively validated. The method qualitatively screens for 320 compounds while simultaneously quantifying 39. Compounds were extracted from the blood using alkaline liquid/liquid extraction and chromatographic separation was achieved in 12 min. The QTOF was operated using positive mode electrospray ionization using data dependent acquisition...
January 10, 2018: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/29328982/systematic-identification-of-suspected-anthelmintic-benzimidazole-metabolites-using-lc-ms-ms
#8
Marius Majewsky, David Castel, Ludivine Le Dret, Pascal Johann, David T Jones, Stefan M Pfister, Walter E Haefeli, Jürgen Burhenne
Metabolite reference standards are often not available, which results in a lack of MS/MS spectra for library matching. Consequently, the identification of suspected metabolites proves to be challenging. The present study aims at structurally elucidating the MS/MS fragmentation behavior of selected benzimidazole anthelmintics to theoretically predict characteristic product ions for rapid and systematic tentative metabolite identification. A set of common characteristic product ions was identified from accurate mass MS/MS experiments for five parent compounds...
December 28, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29310050/explore-the-effects-of-huang-lian-jie-du-tang-on-alzheimer-s-disease-by-uplc-qtof-ms-based-plasma-metabolomics-study
#9
Li-Min Sun, Bao-Jie Zhu, Hui-Ting Cao, Xin-Yi Zhang, Qi-Chun Zhang, Gui-Zhong Xin, Lin-Mei Pan, Li-Fang Liu, Hua-Xu Zhu
Alzheimer's disease (AD) is a progressive neurodegenerative disease with neither definitive pathogenesis nor effective treatment method so far. Huang-Lian-Jie-Du-Tang (HLJDT) is a classic formula of traditional Chinese medicine (TCM) proven to have ameliorative effects on learning and memory deficits of dementia. Morris water maze (MWM) test and pathology analysis have demonstrated that HLJDT could ameliorate learning and memory deficits in AD mouse model, which may act via its anti-neuroinflammation properties...
December 28, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29305931/discrimination-of-three-siegesbeckiae-herba-species-using-uplc-qtof-ms-based-metabolomics-approach
#10
Hong-Xun Tao, Wei Xiong, Guan-Ding Zhao, Yu Peng, Zhang-Feng Zhong, Liang Xu, Ran Duan, Karl W K Tsim, Hua Yu, Yi-Tao Wang
The plant origin is one of the most important factors for the quality control of traditional Chinese medicines (TCMs) and highly affected on their safety and effectiveness in clinical applications. Multi-origin has been widely observed for many TCMs. Siegesbeckiae Herba (SH) is a traditional anti-rheumatic TCM which is originated from the plants of Siegesbeckia pubescens Makino (SP), S. orientalis L. (SO), and S. glabrescens Makino (SG). In the present study, an UPLC-QTOF/MS method were validated and successfully applied for the determination of the chemical profiles in the three SH species...
January 3, 2018: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/29297257/identification-of-polygonum-orientale-constituents-using-high-performance-liquid-chromatography-high-resolution-tandem-mass-spectrometry
#11
Hyeji Shin, Yeeun Park, Young Ho Jeon, Xi-Tao Yan, Ki Yong Lee
Our primary focus in this research was to identify and characterize its bioactive compounds for potential therapeutic use. Twenty-seven metabolites of Polygonum orientale were identified using LC-QTOF tandem mass spectrometry. Interestingly, P. orientale extracts included several highly oxygenated flavonoids were isolated from P. orientale by column chromatography. 13C NMR data of highly oxygenated flavonoids (1-7) are reported here for the first time. In addition, nitric oxide, 1,1-diphenyl-2-picrylhydrazyl, and water-soluble tetrazolium salt assays were carried out on the isolated compounds to investigate their anti-inflammatory, anti-oxidant, and neuroprotective activities, respectively...
January 3, 2018: Bioscience, Biotechnology, and Biochemistry
https://www.readbyqxmd.com/read/29291588/accurate-analysis-of-parabens-in-human-urine-using-isotope-dilution-ultrahigh-performance-liquid-chromatography-high-resolution-mass-spectrometry
#12
Hui-Ting Zhou, Hsin-Chang Chen, Wang-Hsien Ding
An analytical method that utilizes isotope-dilution ultrahigh-performance liquid chromatography coupled with hybrid quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS or called UHPLC-HRMS) was developed, and validated to be highly precise and accurate for the detection of nine parabens (methyl-, ethyl-, propyl-, isopropyl-, butyl-, isobutyl-, pentyl-, hexyl-, and benzyl-parabens) in human urine samples. After sample preparation by ultrasound-assisted emulsification microextraction (USAEME), the extract was directly injected into UHPLC-HRMS...
December 24, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29289287/development-of-matrix-solid-phase-dispersion-method-for-the-extraction-of-short-chain-chlorinated-paraffins-in-human-placenta
#13
Ying Wang, Wei Gao, Jing Wu, Huijin Liu, Yingjun Wang, Yawei Wang, Guibin Jiang
Chlorinated paraffins (SCCPs) are widely used worldwide, and they can be released into the environment during their production, transport, usage and disposal, which pose potential risks for human health. In this work, an efficient, reliable and rapid pretreatment method based on matrix solid-phase dispersion (MSPD) was developed for the analysis of short-chain CPs (SCCPs) in human placenta by gas chromatograph-electron capture negative ion low-resolution mass spectrometry (GC-ECNI-LRMS) and gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-HRMS)...
December 2017: Journal of Environmental Sciences (China)
https://www.readbyqxmd.com/read/29288758/chemical-findings-and-in-vitro-biological-studies-to-uphold-the-use-of-ficus-exasperata-vahl-leaf-and-stem-bark
#14
Didier G Mouho, Andreia P Oliveira, Charles Guillaume Kodjo, Patrícia Valentão, Angel Gil-Izquierdo, Paula B Andrade, Zana Adama Ouattara, Yves-Alain Bekro, Federico Ferreres
Ficus exasperata Vahl, commonly known as sandpaper, is a terrestrial Afro-tropical tree used in popular medicine. Despite the existence of some works on the biological activities of this species, its chemical composition is still poorly known. The aim of this study was to extend the knowledge on the phytochemistry and biological properties of this species. Aqueous extracts from F. exasperata leaves and stem bark were analysed. Thirty-one phenolic compounds, comprising cinnamoyl derivatives, flavonoid-O-glycosides, flavonoid-mono-C-glycosides, flavonoid-di-C-glycosides and one furanocoumarin, were determined by HPLC-DAD-ESI/MSn and UPLC-ESI-QTOF-MS, 26 of them being reported for the first time in this species...
December 27, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/29288756/is-comfrey-root-more-than-toxic-pyrrolizidine-alkaloids-salvianolic-acids-among-antioxidant-polyphenols-in-comfrey-symphytum-officinale-l-roots
#15
Adriana Trifan, Sebastian E W Opitz, Roland Josuran, Andreas Grubelnik, Nils Esslinger, Samuel Peter, Sarah Bräm, Nadja Meier, Evelyn Wolfram
Comfrey root preparations are used for the external treatment of joint distortions and myalgia, due to its analgesic and anti-inflammatory properties. Up to date, key activity-determining constituents of comfrey root extracts have not been completely elucidated. Therefore, we applied different approaches to further characterize a comfrey root extract (65% ethanol). The phenolic profile of comfrey root sample was characterized by HPLC-DAD-QTOF-MS/MS. Rosmarinic acid was identified as main phenolic constituent (7...
December 27, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/29287470/authentication-of-iceland-moss-cetraria-islandica-by-uplc-qtof-ms-chemical-profiling-and-dna-barcoding
#16
Maonian Xu, Starri Heidmarsson, Margret Thorsteinsdottir, Marco Kreuzer, Julie Hawkins, Sesselja Omarsdottir, Elin Soffia Olafsdottir
The lichen Cetraria islandica or Iceland Moss is commonly consumed as tea, food ingredients (e.g. in soup or bread) and herbal medicines. C. islandica, which has two chemotypes, can be difficult to distinguish from the sister species Cetraria ericetorum. They are collectively referred to as the Cetraria islandica species complex. This study aimed to use an UPLC-QToF-MS chemical profiling together with DNA barcoding to distinguish species and chemotypes of the C. islandica species complex. Our results show that the two chemotypes of C...
April 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29287348/evaluation-of-nutritional-and-chemical-composition-of-yacon-syrup-using-1h-nmr-and-uplc-esi-q-tof-mse
#17
Maria de Fátima Gomes da Silva, Ana Paula Dionísio, Fernando Antonio Pinto de Abreu, Edy Sousa de Brito, Nedio Jair Wurlitzer, Lorena Mara Alexandre E Silva, Paulo Riceli Vasconcelos Ribeiro, Sueli Rodrigues, Carlos Alberto Kenji Taniguchi, Dorasilvia Ferreira Pontes
A complete characterization of yacon syrup was performed by analytical techniques, including NMR and UPLC-QTOF-MSE. The effect of the different stages of yacon syrup production on fructooligosaccharides (FOS) and chlorogenic acid (CGA) contents were also evaluated. As a result, in addition to higher levels of FOS and CGA, some mineral elements, such as K, Ca and P, and essential amino acids, such as tryptophan, valine, and threonine, were determined in yacon syrup. Twenty-five compounds were putatively identified, and the main compounds were phenolics derived from quinic and trans-cinnamic acids...
April 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29283379/a-metabolomic-and-lipidomic-serum-signature-from-nonhuman-primates-administered-with-a-promising-radiation-countermeasure-gamma-tocotrienol
#18
Amrita K Cheema, Khyati Y Mehta, Oluseyi O Fatanmi, Stephen Y Wise, Charles P Hinzman, Josh Wolff, Vijay K Singh
The development of radiation countermeasures for acute radiation syndrome (ARS) has been underway for the past six decades, leading to the identification of multiple classes of radiation countermeasures. However, to date, only two growth factors (Neupogen and Neulasta) have been approved by the United States Food and Drug Administration (US FDA) for the mitigation of hematopoietic acute radiation syndrome (H-ARS). No radioprotector for ARS has been approved by the FDA yet. Gamma-tocotrienol (GT3) has been demonstrated to have radioprotective efficacy in murine as well as nonhuman primate (NHP) models...
December 28, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/29279031/the-classification-of-almonds-prunus-dulcis-by-country-and-variety-using-uhplc-hrms-based-untargeted-metabolomics
#19
R Gil Solsona, C Boix, M Ibáñez, J V Sancho
The aim of this study was to use an untargeted UHPLC-HRMS-based metabolomics approach allowing discrimination between almonds based on their origin and variety. Samples were homogenized, extracted with ACN:H2O (80:20) containing 0.1% HCOOH and injected in a UHPLC-QTOF instrument in both positive and negative ionization modes. Principal component analysis (PCA) was performed to ensure the absence of outliers. Partial least squares - discriminant analysis (PLS-DA) was employed to create and validate the models for country (with 5 different compounds) and variety (with 20 features), showing more than 95% accuracy...
December 26, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29278908/comprehensive-characterization-of-extractable-and-non-extractable-phenolic-compounds-by-hplc-esi-qtof-of-a-grape-pomegranate-pomace-dietary-supplement
#20
Iza Pérez-Ramírez, Rosalia Reynoso-Camacho, Fulgencio Saura Calixto, Jara Pérez-Jiménez
Grape and pomegranate are rich sources of phenolic compounds and their derived products could be used as ingredients for the development of functional foods and dietary supplements. However, the profile of non-extractable or macromolecular phenolic compounds in these samples has not been evaluated. Here, we a comprehensive characterization of extractable and non-extractable phenolic compounds of a grape/pomegranate pomace dietary supplement using high-performance liquid chromatography-quadrupole time-of-flight (HPLC-ESI-QTOF) and matrix-assisted laser desorption/ionization MALDI-TOF techniques...
December 27, 2017: Journal of Agricultural and Food Chemistry
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