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https://www.readbyqxmd.com/read/28088278/metabolomic-analysis-of-urine-samples-by-uhplc-qtof-ms-impact-of-normalization-strategies
#1
Yoric Gagnebin, David Tonoli, Pierre Lescuyer, Belen Ponte, Sophie de Seigneux, Pierre-Yves Martin, Julie Schappler, Julien Boccard, Serge Rudaz
Among the various biological matrices used in metabolomics, urine is a biofluid of major interest because of its non-invasive collection and its availability in large quantities. However, significant sources of variability in urine metabolomics based on UHPLC-MS are related to the analytical drift and variation of the sample concentration, thus requiring normalization. A sequential normalization strategy was developed to remove these detrimental effects, including: (i) pre-acquisition sample normalization by individual dilution factors to narrow the concentration range and to standardize the analytical conditions, (ii) post-acquisition data normalization by quality control-based robust LOESS signal correction (QC-RLSC) to correct for potential analytical drift, and (iii) post-acquisition data normalization by MS total useful signal (MSTUS) or probabilistic quotient normalization (PQN) to prevent the impact of concentration variability...
February 22, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28081501/isolation-characterization-using-lc-esi-qtof-nmr-and-in-vitro-cytotoxicity-assay-of-niclosamide-forced-degradation-products
#2
Johnsirani P, Vishnuvardhan Ch, Lingesh A, Naidu V G M, Naveen Ch, Satheeshkumar N
The present study describes the isolation, characterization and in vitro cytotoxic effect of all forced degradation products of niclosamide (NCM) an anthelmintic class of drug used specifically to treat tapeworms. NCM was subjected to forced degradation involving hydrolysis (acidic, alkaline and neutral), oxidative, photolysis and thermal stress, as per ICH (Q1A (R2)) suggested conditions. The drug under hydrolytic (acidic and basic) conditions showed extensive degradation, while it was stable under neutral hydrolytic, oxidative, photolytic and thermal stress conditions...
January 3, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28067965/rp-hplc-dad-esi-qtof-ms-based-metabolic-profiling-of-the-potential-olea-europaea-by-product-wood-and-its-comparison-with-leaf-counterpart
#3
Sonda Ammar, Maria Del Mar Contreras, Boutheina Gargouri, Antonio Segura-Carretero, Mohamed Bouaziz
INTRODUCTION: Olea europaea L. organs such as leaves, stems and roots have been associated with numerous in vivo and in vitro biological activities and used for traditional medicinal purposes. However, tree wood is an untapped resource with little information about their chemical composition. OBJECTIVE: That is why, the objective of this study is to increase the knowledge about phytochemicals from 'Chemlali' olive wood by means of mass spectrometry-based analyses...
January 9, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28063302/metabonomics-study-of-the-therapeutic-mechanism-of-fenugreek-galactomannan-on-diabetic-hyperglycemia-in-rats-by-ultra-performance-liquid-chromatography-coupled-with-quadrupole-time-of-flight-mass-spectrometry
#4
Wenyue Jiang, Lu Gao, Pengdong Li, Hong Kan, Jiale Qu, Lihui Men, Zhiqiang Liu, Zhongying Liu
Fenugreek is a traditional plant for the treatment of diabetes. Galactomannan, an active major component in fenugreek seeds, has shown hypoglycemic activity. The present study was performed to investigate the therapeutic mechanism underlying fenugreek galactomannan (F-GAL) in treating diabetes, using a metabonomics approach based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). The F-GAL used for study was highly purified, and its yield, purity, and galactose/mannose ratio were characterized by capillary zone electrophoresis (CZE) and a modified phenol-sulfuric acid method...
December 29, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28063270/identification-and-analytical-characterization-of-six-synthetic-cannabinoids-nnl-3-5%C3%A2-f-npb-22-7%C3%A2-n-5%C3%A2-f-akb-48-7%C3%A2-n-5%C3%A2-f-edmb-pinaca-emb-fubinaca-and-eg-018
#5
Cuimei Liu, Wei Jia, Zhendong Hua, Zhenhua Qian
Clinical and forensic toxicology laboratories are continuously confronted by analytical challenges when dealing with the new psychoactive substances phenomenon. The number of synthetic cannabinoids, the chemical diversity, and the speed of emergence make this group of compounds particularly challenging in terms of detection, monitoring, and responding. Three indazole 7 N positional isomer synthetic cannabinoids, two ethyl 2-amino-3-methylbutanoate-type synthetic cannabinoids, and one 9H-carbazole substituted synthetic cannabinoid were identified in seized materials...
January 7, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28059581/hot-and-cold-drugs-national-park-service-medication-stability-at-the-extremes-of-temperature
#6
Patil Armenian, Danielle Campagne, Geoff Stroh, Crystal Ives Tallman, William Z D Zeng, Thomas Lin, Roy R Gerona
STUDY OBJECTIVE: National Park Service (NPS) Parkmedics provide medical care in austere environments. The objective of this study was to evaluate the stability of specific medications used by Parkmedics at extremes of temperatures likely to be faced in the field. METHODS: This is a bench research study conducted in the laboratory setting over a 4-week period. Parenteral medications were separated into 4 temperature exposure groups: A) 45°C (hot); B) -20°C (cold); C) hot then cold temperatures alternating weekly; and D) cold then hot temperatures alternating weekly...
January 6, 2017: Prehospital Emergency Care
https://www.readbyqxmd.com/read/28050844/microbial-nitrate-removal-by-waste-iron-shavings-from-the-biological-and-catalytic-ozonation-treated-dyeing-and-finishing-wastewater
#7
Jieting Ma, Yunlu Chen, Gang Luo, Jianxin Nie, Zhigang Guo, Yan Liu, Luming Ma
The concentration of total nitrogen (TN) (between 40 and 60 mg/L, mainly nitrate) in the biological and catalytic ozonation treated dyeing and finishing wastewater needs to be reduced before discharge. The present study investigated the feasibility of using waste iron shavings as electron donor for nitrogen removal by biological denitrification. Two anoxic sequencing batch reactors (AnSBR) were continuously operated for more than 100 days. The results showed that the TN removal efficiency increased from 12% in the control reactor (AnSBR-C) to 20% in the reactor with waste iron shavings (AnSBR-Fe)...
December 2017: AMB Express
https://www.readbyqxmd.com/read/28035035/analysis-of-u-47700-a-novel-synthetic-opioid-in-human-urine-by-lc-ms-ms-and-lc-qtof
#8
Steven W Fleming, Justin C Cooley, Leonard Johnson, C Clinton Frazee, Kristina Domanski, Kurt Kleinschmidt, Uttam Garg
The illicit drug market has rapidly evolved from synthetic cannabinoids to cathinone derivatives and now a new emerging threat of synthetic opioids. These compounds were mostly developed by pharmaceutical companies during drug discovery. The new psychoactive substances are not routinely covered in drug screening and may go undetected. Recently fentanyl analogous, AH-7921, MT-45 and now U-47700 have been encountered in clinical and forensic casework. U-47700 is gaining popularity on drug user forms as a legal alternative to heroin...
December 29, 2016: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28026950/lc-and-gc-qtof-ms-as-complementary-tools-for-a-comprehensive-micropollutant-analysis-in-aquatic-systems
#9
Christoph Moschet, Bonny M Lew, Simone Hasenbein, Tarun Anumol, Thomas M Young
Efficient strategies are required to implement comprehensive suspect screening methods using high-resolution mass spectrometry within environmental monitoring campaigns. In this study, both liquid and gas chromatography time-of-flight mass spectrometry (LC-QTOF-MS and GC-QTOF-MS) were used to screen for >5000 target and suspect compounds in the Sacramento-San Joaquin River Delta in Northern California. LC-QTOF-MS data were acquired in All-Ions fragmentation mode in both positive and negative electrospray ionization (ESI)...
January 18, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28018478/rapid-differentiation-of-xihuangcao-from-the-three-isodon-species-by-uplc-esi-qtof-ms-ms-and-chemometrics-analysis
#10
Lai Lai Wong, Zhitao Liang, Hubiao Chen, Zhongzhen Zhao
BACKGROUND: Isodon lophanthoides, I. lophanthoides var. graciliflorus and I. serra are the three botanical sources of Xihuangcao, which are often used indiscriminately in herbal products. The aim of this study was to develop a rapid and accurate analytical method to identify the three different botanical sources of Xihuangcao by combining UPLC-ESI-QTOF-MS with chemometrics analysis. METHODS: Fifteen batches of plants were collected as reference materials and their chemical profiles were analyzed by UPLC-ESI-QTOF-MS...
2016: Chinese Medicine
https://www.readbyqxmd.com/read/28018403/comparative-analysis-of-phenolic-compound-characterization-and-their-biosynthesis-genes-between-two-diverse-bread-wheat-triticum-aestivum-varieties-differing-for-chapatti-unleavened-flat-bread-quality
#11
Monica Sharma, Rajat Sandhir, Anuradha Singh, Pankaj Kumar, Ankita Mishra, Sanjay Jachak, Sukhvinder P Singh, Jagdeep Singh, Joy Roy
Phenolic compounds (PCs) affect the bread quality and can also affect the other types of end-use food products such as chapatti (unleavened flat bread), now globally recognized wheat-based food product. The detailed analysis of PCs and their biosynthesis genes in diverse bread wheat (Triticum aestivum) varieties differing for chapatti quality have not been studied. In this study, the identification and quantification of PCs using UPLC-QTOF-MS and/or MS/MS and functional genomics techniques such as microarrays and qRT-PCR of their biosynthesis genes have been studied in a good chapatti variety, "C 306" and a poor chapatti variety, "Sonalika...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28001159/effect-of-cu-ii-on-in-vitro-glycation-of-human-serum-albumin-by-methylglyoxal-a-lc-ms-based-proteomic-approach
#12
Alejandra Sarahi Ramirez Segovia, Kazimierz Wrobel, Francisco Javier Acevedo Aguilar, Alma Rosa Corrales Escobosa, Katarzyna Wrobel
It has been reported that glycation of human serum albumin (HSA) changes its capability for copper binding whereas the increase of free copper might have an impact on protein glycation - a key process in diabetes progression. In this work, proteomic analysis of non-glycated HSA and HSA glycated with methylglyoxal (MGo) in the absence or in the presence of Cu(ii) (0.1; 1.0; 5.0 mg Cu L(-1)) has been undertaken. Trypsin hydrolysates were subjected to capillary HPLC-ESI-QTOF-MS and MS/MS. Raw data were analyzed using two proteomic platforms: MaxQuant () and ProteinScape (Bruker)...
December 21, 2016: Metallomics: Integrated Biometal Science
https://www.readbyqxmd.com/read/27996252/the-formation-and-occurrence-of-n-chloro-2-2-dichloroacetamide-a-previously-overlooked-nitrogenous-disinfection-byproduct-in-chlorinated-drinking-waters
#13
Yun Yu, David A Reckhow
Haloacetamides (HAMs) are a class of newly identified nitrogenous disinfection byproducts (N-DBPs) whose occurrence in drinking waters has recently been reported in several DBP surveys. As the most prominent HAM species, it is commonly acknowledged that 2,2-dichloroacetamide (DCAM) is mainly generated from dichloroacetonitrile (DCAN) hydrolysis because the concentrations of these two compounds are often well correlated. Instead of DCAM, a previously unreported N-DBP, N-chloro-2,2-dichloroacetamide (N-Cl-DCAM), was confirmed in this study as the actual DCAN degradation product in chlorinated drinking waters...
December 20, 2016: Environmental Science & Technology
https://www.readbyqxmd.com/read/27995753/differential-proteomic-analysis-of-white-adipose-tissues-from-t2d-kkay-mice-by-lc-esi-qtof
#14
Ming Ke, Hanyan Wu, Zhaoyang Zhu, Chi Zhang, Yongqian Zhang, Yunlin Deng
T2D has become a worldwide increasingly social health burden for its high morbidity and heightened prevalence. As one of the main tissues involved in uptake of glucose under the stimulation of insulin, WAT plays very important role in metabolic and homeostasis regulation. We performed a differential proteomics study to investigate alterations in epididymis fat pad of HFD fed T2D KKAy mice compared to normal fed C57BL/6J mice, by (18) O-labeling relative quantitative technique. Among 329 confidently identified proteins, 121 proteins showed significant changes with CV ≤ 20% (fold changes of >2 or <0...
December 20, 2016: Proteomics
https://www.readbyqxmd.com/read/27992229/comprehensive-metabolomic-and-lipidomic-profiling-of-human-kidney-tissue-a-platform-comparison
#15
Patrick Leuthold, Elke Schaeffeler, Stefan Winter, Florian Büttner, Ute Hofmann, Thomas E Mürdter, Steffen Rausch, Denise Sonntag, Judith Wahrheit, Falko Fend, Jörg Hennenlotter, Jens Bedke, Matthias Schwab, Mathias Haag
Metabolite profiling of tissue samples is a promising approach for the characterization of cancer pathways and tumor classification based on metabolic features. Here, we present an analytical method for non-targeted metabolomics of kidney tissue. Capitalizing on different chemical properties of metabolites allowed us to extract a broad range of molecules covering small polar molecules and less polar lipid classes that were analyzed by LC-QTOF-MS after HILIC and RP chromatographic separation, respectively. More than 1000 features could be reproducibly extracted and analyzed (CV < 30%) in porcine and human kidney tissue which were used as surrogate matrices for method development...
December 19, 2016: Journal of Proteome Research
https://www.readbyqxmd.com/read/27989939/high-resolution-mass-spectrometry-based-global-proteomic-analysis-of-probiotic-strains-lactobacillus-fermentum-ncdc-400-and-rs2
#16
Parijat Pragya, Gurjeet Kaur, Syed Azmal Ali, Shveta Bhatla, Preeti Rawat, Vaibhao Lule, Sudarshan Kumar, Ashok Kumar Mohanty, Pradip Behare
Lactobacillus fermentum strains NCDC 400 and RS2, previously isolated from dairy sources, exhibited excellent probiotic properties were studied for the global proteomic profile. A total of 1125 proteins were identified by a high-resolution mass spectrometer, ESI-qTOF (nano-LC-MS/MS) in the strains of L. fermentum. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis resulted in 60.9% and 59.2% of the total proteins were functionally annotated for NCDC 400 and RS2 respectively. Simultaneously, a cluster of orthologous groups (COGs) and KEGG together revealed the presence of a significant number of proteins involved in transcription, translation, chaperones, peptidoglycan biosynthesis, nucleotide, amino acid and carbohydrate metabolism...
January 30, 2017: Journal of Proteomics
https://www.readbyqxmd.com/read/27984853/butia-spp-arecaceae-lc-ms-based-metabolomics-for-species-and-geographical-origin-discrimination
#17
Jessica Fernanda Hoffmann, Ivan Ricardo Carvalho, Rosa Lia Barbieri, Cesar Valmor Rombaldi, Fabio Clasen Chaves
The metabolic variability of fruit from Butia spp. (Arecaceae) genotypes from different geographical locations was characterized using untargeted metabolomics by liquid chromatography-mass spectrometry (LC-MS) followed by multivariate data analyses. Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) from LC-MS data sets showed a clear distinction among Butia catarinensis, Butia odorata, Butia paraguayensis, and Butia yatay. The major metabolites that contributed to species discrimination were primary metabolites including sugars and organic acids and specialized metabolites such as tetrahydroxy-trans-stilbene and rutin...
January 18, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/27979195/untargeted-metabolomic-analysis-of-human-serum-samples-associated-with-different-levels-of-red-meat-consumption-a-possible-indicator-of-type-2-diabetes
#18
Daniel Carrizo, Olivier P Chevallier, Jayne V Woodside, Sarah F Brennan, Marie M Cantwell, Geraldine Cuskelly, Christopher T Elliott
Red meat consumption has been associated with negative health effects. A study to identify biomarkers of meat consumption was undertaken using serum samples collected from combining high resolution mass spectrometry (UPLC-QTof-MS) and chemometrics. Using orthogonal partial last-squares discriminant analysis (OPLS-DA), multivariate models were created for both modes of acquisition (ESI-/ESI+) and red meat intake classes (YES/NO). In the serum samples, a total 3280 and 3225 ions of interest were detected in positive and negative modes, respectively...
April 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27978466/metabolite-identification-of-bentysrepinine-y101-a-novel-anti-hbv-agent-in-rats-using-a-five-step-strategy-based-on-a-combined-workflow-with-two-different-platforms-of-liquid-chromatography-tandem-mass-spectrometry
#19
Huirong Fan, Zhanxing Hu, Ruixing Li, Shiqi Dong, Yuan Gu, Ting Liu, Duanyun Si, Guangyi Liang, Changxiao Liu
Bentysrepinine (Y101), a derivative of repensine (a compound isolated from Dichondrarepens Forst), is a novel phenyalanine dipeptide inhibiting DNA-HBV and cccDNA activities and is currently under development for the treatment of hepatitis B virus (HBV)-infected hepatitis. Our previous study implied that there might be an existence of extensive metabolism of Y101 in rats. Therefore, it is necessary to perform metabolic profiling study to further evaluate its safety and drug-like properties. In this study, the metabolism of Y101 in rats was investigated by a convincible five-step strategy to characterize metabolites in plasma and that excreted into urine, bile and feces...
January 1, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/27976470/esi-ms-2-and-anti-inflammatory-studies-of-cyclopropanic-triterpenes-uplc-esi-ms-and-ms-2-search-of-related-metabolites-from-donella-ubanguiensis
#20
Louis P Sandjo, Marcus V P Dos Santos Nascimento, Layzon A L da Silva, Antonio C M Munhoz, Luiz A E Pollo, Maique W Biavatti, Bonaventure T Ngadjui, Till Opatz, Tania S Fröde
INTRODUCTION: Triterpenes are one of the largest secondary metabolites groups spread in the plant kingdom with various skeletons. These metabolites have showed various bioactivities including anti-inflammatory activity. OBJECTIVE: The study aims to explore the mass spectrometry fragmentation of donellanic acids A-C (DA A-C), three compounds identified from Donella ubanguiensis; in addition, the fragmentation behaviour of these metabolites will serve as a fingerprint to search and characterise triterpenes congeners in fruits, bark and wood crude extracts of D...
January 2017: Phytochemical Analysis: PCA
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