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https://www.readbyqxmd.com/read/27910903/prostate-cancer-patients-negative-biopsy-controls-discrimination-by-untargeted-metabolomics-analysis-of-urine-by-lc-qtof-upstream-information-on-other-omics
#1
M A Fernández-Peralbo, E Gómez-Gómez, M Calderón-Santiago, J Carrasco-Valiente, J Ruiz-García, M J Requena-Tapia, M D Luque de Castro, F Priego-Capote
The existing clinical biomarkers for prostate cancer (PCa) diagnosis are far from ideal (e.g., the prostate specific antigen (PSA) serum level suffers from lack of specificity, providing frequent false positives leading to over-diagnosis). A key step in the search for minimum invasive tests to complement or replace PSA should be supported on the changes experienced by the biochemical pathways in PCa patients as compared to negative biopsy control individuals. In this research a comprehensive global analysis by LC-QTOF was applied to urine from 62 patients with a clinically significant PCa and 42 healthy individuals, both groups confirmed by biopsy...
December 2, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27910174/combined-application-of-uhplc-qtof-ms-hplc-elsd-and-1-h-nmr-spectroscopy-for-quality-assessment-of-da-9801-a-standardised-dioscorea-extract
#2
Kyo Bin Kang, Jayoung Ryu, Youngwoong Cho, Sang-Zin Choi, Miwon Son, Sang Hyun Sung
INTRODUCTION: DA-9801, a standardised 50% aqueous ethanolic extract of a mixture of Dioscorea japonica and D. nipponica, is a botanical drug candidate for the treatment of diabetic neuropathy, which finished its US phase II clinical trials recently. An advanced quality control method is needed for further development of DA-9801, considering its high contents of both primary and secondary metabolites. OBJECTIVE: Development of a quality assessment strategy for DA-9801, based on the combination of UHPLC-QTOF/MS, HPLC-ELSD, and (1) H-NMR spectroscopy...
December 1, 2016: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/27901640/a-traceable-reference-for-direct-comparative-assessment-of-total-naphthenic-acid-concentrations-in-commercial-and-acid-extractable-organic-mixtures-derived-from-oil-sands-process-water
#3
Pamela Brunswick, L Mark Hewitt, Richard A Frank, Marcus Kim, Graham van Aggelen, Dayue Shang
The advantage of using naphthenic acid (NA) mixtures for the determination of total NA lies in their chemical characteristics and identification of retention times distinct from isobaric interferences. However, the differing homolog profiles and unknown chemical structures of NA mixtures do not allow them to be considered a traceable reference material. The current study provides a new tool for the comparative assessment of different NA mixtures by direct reference to a single, well-defined and traceable compound, decanoic-d19 acid...
November 30, 2016: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
https://www.readbyqxmd.com/read/27894965/an-application-of-mass-spectrometry-for-quality-control-of-biologicals-highly-sensitive-profiling-of-plasma-residuals-in-human-plasma-derived-immunoglobulin
#4
Franck Limonier, Katleen Van Steendam, Geneviève Waeterloos, Koen Brusselmans, Myriam Sneyers, Dieter Deforce
: Thromboembolic events (TEE) associated to trace amounts of plasmatic activated coagulation factor XI (FXIa) in administrated immunoglobulin (Ig) have recently raised concerns and hence there is a need for highly sensitive profiling of residual plasma source proteins. This study aims to consider LC-ESI-QTOF data-dependent acquisition in combination with sample fractionation for this purpose. Sample fractionation proved mandatory to enable identification of plasma residuals. Two approaches were compared: Ig depletion with protein G - protein A affinity chromatography and low-abundant protein enrichment with a combinatorial peptide ligand library (ProteoMiner(TM), Bio-Rad)...
November 25, 2016: Journal of Proteomics
https://www.readbyqxmd.com/read/27894005/uplc-qtof-analysis-reveals-metabolomic-changes-in-the-flag-leaf-of-wheat-triticum-aestivum-l-under-low-nitrogen-stress
#5
Yang Zhang, Xin-Ming Ma, Xiao-Chun Wang, Ji-Hong Liu, Bing-Yan Huang, Xiao-Yang Guo, Shu-Ping Xiong, Gui-Xiao La
Wheat is one of the most important grain crop plants worldwide. Nitrogen (N) is an essential macronutrient for the growth and development of wheat and exerts a marked influence on its metabolites. To investigate the influence of low nitrogen stress on various metabolites of the flag leaf of wheat (Triticum aestivum L.), a metabolomic analysis of two wheat cultivars under different induced nitrogen levels was conducted during two important growth periods based on large-scale untargeted metabolomic analysis using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF)...
November 18, 2016: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/27891064/proteomic-based-approach-for-characterizing-4-hydroxy-2-nonenal-induced-oxidation-of-buffalo-bubalus-bubalis-and-goat-capra-hircus-meat-myoglobins
#6
Naveena B Maheswarappa, K Usha Rani, Y Praveen Kumar, Vinayak V Kulkarni, Srikanth Rapole
BACKGROUND: Myoglobin (Mb) is a sarcoplasmic heme protein primarily responsible for meat color and its chemistry is species specific. 4-hydroxy-2-nonenal (HNE) is a cytotoxic lipid derived aldehyde detected in meat and was reported to covalently adduct with nucleophilic histidine residues of Mb and predispose it to greater oxidation. However, no literature is available on characterization of lipid oxidation induced oxidation of Indian water buffalo (Bubalus bubalis) and goat (Capra hircus) myoglobins...
2016: Proteome Science
https://www.readbyqxmd.com/read/27888309/selective-quantification-of-doss-in-marine-sediment-and-sediment-trap-solids-by-lc-qtof-ms
#7
Matt J Perkins, Samantha B Joye, Jennifer A Field
At the onset of the 2010 Gulf oil spill, analytical methods for the quantification of the surfactants in Corexit did not exist in the peer-reviewed literature. To date, only a single study reports the presence of bis-(2-ethylhexyl) sodium sulfosuccinate (DOSS) in deep-sea Gulf sediment collected in 2010 from a single location. There are no data on the occurrence of DOSS in association with settling solids (i.e., sediment-trap solids). To address this data gap, DOSS was initially quantified by liquid chromatography tandem quadrupole mass spectrometry (LC-MS/MS) in sediment and sediment-trap solids collected from multiple sites in the Gulf between 2010 and 2013...
November 25, 2016: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/27882564/processing-black-mulberry-into-jam-effects-on-antioxidant-potential-and-in-vitro-bioaccessibility
#8
Merve Tomas, Gamze Toydemir, Dilek Boyacioglu, Robert D Hall, Jules Beekwilder, Esra Capanoglu
BACKGROUND: Black mulberries (Morus nigra) were processed into jam on an industrialized scale, including the major steps of: selection of frozen black mulberries, adding glucose-fructose syrup and water, cooking, adding citric acid and apple pectin, removing seeds, and pasteurization. Qualitative and quantitative determinations of antioxidants in black mulberry samples were performed using spectrophotometric methods, as well as HPLC- and LC-QTOF-MS-based measurements. These analyses included the determination of total polyphenolic content, percent polymeric color, total and individual anthocyanin contents, antioxidant capacity, and in vitro bioaccessibility in processing samples...
November 23, 2016: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/27881618/simultaneous-screening-and-quantification-of-basic-neutral-and-acidic-drugs-in-blood-using-uplc-qtof-ms
#9
Sergei Bidny, Kim Gago, Phuong Chung, Desdemona Albertyn, Daniel Pasin
An analytical method using ultra performance liquid chromatography (UPLC) quadrupole time-of-flight mass spectrometry (QTOF-MS) was developed and validated for the targeted toxicological screening and quantification of commonly used pharmaceuticals and drugs of abuse in postmortem blood using 100 µL sample. It screens for more than 185 drugs and metabolites and quantifies more than 90 drugs. The selected compounds include classes of pharmaceuticals and drugs of abuse such as: antidepressants, antipsychotics, analgesics (including narcotic analgesics), anti-inflammatory drugs, benzodiazepines, beta-blockers, amphetamines, new psychoactive substances (NPS), cocaine and metabolites...
November 22, 2016: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/27871726/identification-and-determination-of-chlorinated-azoles-in-sludge-using-liquid-chromatography-quadrupole-time-of-flight-and-triple-quadrupole-mass-spectrometry-platforms
#10
G Castro, M Roca, I Rodríguez, M Ramil, R Cela
Four antimycotic drugs (tioconazole, TCZ; sertaconazole, STZ; fenticonazole, FTZ and itraconazole, ITZ) and the fungicide imazalil (IMZ) are determined in sludge from sewage treatment plants (STPs) following a bottom-up analytical strategy. First, sludge extracts, obtained under different sample preparation conditions, were analyzed by liquid chromatography (LC) quadrupole time-of-flight (QTOF) mass spectrometry (MS). A non-target search strategy, combined with the use of the chlorine mass filter, permitted to detect several chlorinated pollutants including the above referred azoles, which either had not been previously reported (TCZ, STZ, FTZ and ITZ), or scarcely investigated (IMZ), in this environmental compartment...
November 15, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27863836/looking-at-flubromazolam-metabolism-from-four-different-angles-metabolite-profiling-in-human-liver-microsomes-human-hepatocytes-mice-and-authentic-human-urine-samples-with-liquid-chromatography-high-resolution-mass-spectrometry
#11
Ariane Wohlfarth, Svante Vikingsson, Markus Roman, Mikael Andersson, Fredrik C Kugelberg, Henrik Green, Robert Kronstrand
Flubromazolam is a triazolam benzodiazepine that recently emerged as a new psychoactive substance. Since metabolism data are scarce and good analytical targets besides the parent are unknown, we investigated flubromazolam metabolism in vitro and in vivo. 10μmol/L flubromazolam was incubated with human liver microsomes for 1h and with cryopreserved human hepatocytes for 5h. Mice were administered 0.5 or 1.0mg flubromazolam/kg body weight intraperitoneally, urine was collected for 24h. All samples, together with six authentic forensic human case specimens, were analyzed (with or without hydrolysis, in case it was urine) by UHPLC-HRMS on an Acquity HSS T3 column with an Agilent 6550 QTOF...
November 5, 2016: Forensic Science International
https://www.readbyqxmd.com/read/27863142/identification-and-analytical-characterization-of-nine-synthetic-cathinone-derivatives-n-ethylhexedrone-4-cl-pentedrone-4-cl-%C3%AE-eapp-propylone-n-ethylnorpentylone-6-meo-bk-mdma-%C3%AE-pihp-4-cl-%C3%AE-php-and-4-f-%C3%AE-php
#12
Cuimei Liu, Wei Jia, Tao Li, Zhendong Hua, Zhenhua Qian
Clinical and forensic toxicology laboratories are continuously confronted by analytical challenges when dealing with the new psychoactive substances phenomenon. In this study, the analytical characterization of nine synthetic cathinones is described: 2-(ethylamino)-1-phenylhexan-1-one (N-ethylhexedrone 1), 1-(4-chlorophenyl)-2-(methylamino)pentan-1-one (4-Cl-pentedrone 2), 1-(4-chlorophenyl)-2-(ethylamino)pentan-1-one (4-Cl-α-EAPP 3), 1-(3,4-methylenedioxyphenyl)-2-propylaminopropan-1-one (propylone 4), 1-(3,4-methylenedioxyphenyl)-2-ethylaminopentan-1-one (N-ethylnorpentylone 5), 1-(6-methoxy-3,4-methylenedioxyphenyl)-2-methylaminopropan-1-one (6-MeO-bk-MDMA 6), 4-methyl-1-phenyl-2-(pyrrolidin-1-yl)pentan-1-one (α-PiHP 7), 1-(4-chlorophenyl)-2-(pyrrolidin-1-yl)hexan-1-one (4-Cl-α-PHP 8), and 1-(4-fluorophenyl)-2-(pyrrolidin-1-yl)hexan-1-one (4-F-α-PHP 9)...
November 9, 2016: Drug Testing and Analysis
https://www.readbyqxmd.com/read/27862504/assignment-of-sugar-arrangement-in-branched-steviol-glycosides-using-esi-qtof-ms-ms
#13
Wilmer H Perera, Bharathi Avula, Ikhlas A Khan, James D McChesney
RATIONALE: Steviol glycosides with an ent-kaurene core are being used in the Food Industry as non-caloric sweeteners. These compounds are chemically similar in terms of sugar types and sugar arrangements. In order to assign sugar positions, we describe herein, the dissociation pattern for steviol glycosides under varying collision energies. METHODS: Steviol glycosides (1 mg/mL, 2 μL) were automatically injected into the mass spectrometer by direct infusion using a 100-well tray autosampler...
November 8, 2016: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/27860448/applicability-of-ultra-high-performance-liquid-chromatography-quadrupole-time-of-flight-mass-spectrometry-for-cocaine-profiling
#14
Cuimei Liu, Zhendong Hua, Xin Meng
For the first time in China, the chemical profiling of cocaine specimens was performed at the National Narcotics Laboratory. An ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry (UHPLC-QTOF-MS) method was developed and validated for simultaneous analysis of 14 cocaine alkaloids and 5 main adulterants. Among them, ecgonine methyl ester, ecgonine, benzoylecgonine, and norcocaine were identified by comparing with the standard materials; tropacocaine, 3,4,5-trimethoxycocaine, cis and trans cinnamoylcocaine were tentatively identified based on the exact masses of protonated molecules and product ions; six unidentified alkaloids of 182/1...
November 8, 2016: Drug Testing and Analysis
https://www.readbyqxmd.com/read/27855939/interaction-of-free-arginine-and-guanidine-with-glucose-under-thermal-processing-conditions-and-formation-of-amadori-derived-imidazolones
#15
Yuchen Zhu, Varoujan A Yaylayan
To investigate the reactivity of free guanidine and arginine in the formation of imidazolinone derivatives, model systems of guanidine or arginine/glucose or (13)[C-6]-glucose were heated in aqueous solutions at110°C for 3h and the residues were analyzed by ESI/qTOF/MS using MS/MS and isotope labeling techniques. The analysis of the data indicated that guanidine and arginine formed both covalent and non-covalent interaction products. Covalent interactions included Amadori rearrangement at the α-nitrogen with glucose and imidazolinone formation with 3-deoxy-glucosone at the guanidine side-chain...
April 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27855932/industrial-processing-versus-home-processing-of-tomato-sauce-effects-on-phenolics-flavonoids-and-in-vitro-bioaccessibility-of-antioxidants
#16
Merve Tomas, Jules Beekwilder, Robert D Hall, Osman Sagdic, Dilek Boyacioglu, Esra Capanoglu
The effect of industrial and home processing, in vitro gastrointestinal digestion, individual phenolic content, and antioxidant capacity of tomato into tomato sauce were investigated. Industrial processing of tomato fruit into sauce had an overall positive effect on the total antioxidant capacity (∼1.2-fold higher) compared to tomato fruit whereas home processing of tomato fruit into sauce led to a decrease in these values. Untargeted LC-QTOF-MS analysis revealed 31 compounds in tomato that changed upon processing, of which 18 could be putatively identified...
April 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27853831/role-of-the-lipid-regulated-nf-%C3%AE%C2%BAb-il-6-stat3-axis-in-alpha-naphthyl-isothiocyanate-induced-liver-injury
#17
Zhong-Ze Fang, Naoki Tanaka, Dan Lu, Chang-Tao Jiang, Wei-Hua Zhang, Chunze Zhang, Zuo Du, Zhi-Wei Fu, Peng Gao, Yun-Feng Cao, Hong-Zhi Sun, Zhi-Tu Zhu, Yan Cai, Kristopher W Krausz, Zhi Yao, Frank J Gonzalez
Alpha-naphthyl isothiocyanate (ANIT)-induced liver damage is regarded as a useful model to study drug-induced cholestatic hepatitis. Ultra-performance liquid chromatography coupled with electrospray ionization quadrupole mass spectrometry (UPLC-ESI-QTOF MS)-based metabolomics revealed clues to the mechanism of ANIT-induced liver injury, which facilitates the elucidation of drug-induced liver toxicity. 1-Stearoyl-2-hydroxy-sn-glycero-3-phosphocholine (LPC 18:0) and 1-oleoyl-2-hydroxy-sn-glycero-3-phosphocholine (LPC 18:1) were significantly increased in serum from ANIT-treated mice, and this increase resulted from altered expression of genes encoding the lipid metabolism enzymes Chka and Scd1...
November 16, 2016: Archives of Toxicology
https://www.readbyqxmd.com/read/27852124/metabolic-profiling-of-liver-tissue-in-diabetic-mice-treated-with-artemisia-capillaris-and-alisma-rhizome-using-lc-ms-and-ce-ms
#18
Yumi Kim, In-Seung Lee, Kang-Hoon Kim, Jiyoung Park, Ji-Hyun Lee, Eunjung Bang, Hyeung-Jin Jang, Yun-Cheol Na
Artemisia Capillaris (AC) and Alisma Rhizome (AR) are natural products for the treatment of liver disorders in oriental medicine clinics. Here, we report metabolomic changes in the evaluation of the treatment effects of AC and AR on fatty livers in diabetic mice, along with a proposition of the underlying metabolic pathway. Hydrophobic and hydrophilic metabolites extracted from mouse livers were analyzed using HPLC-QTOF and CE-QTOF, respectively, to generate metabolic profiles. Statistical analysis of the metabolites by PLS-DA and OPLA-DA fairly discriminated between the diabetic, and the AC- and AR-treated mice groups...
November 16, 2016: American Journal of Chinese Medicine
https://www.readbyqxmd.com/read/27836228/avoiding-hard-chromatographic-segmentation-a-moving-window-approach-for-the-automated-resolution-of-gas-chromatography-mass-spectrometry-based-metabolomics-signals-by-multivariate-methods
#19
Xavier Domingo-Almenara, Alexandre Perera, Jesus Brezmes
Gas chromatography-mass spectrometry (GC-MS) produces large and complex datasets characterized by co-eluted compounds and at trace levels, and with a distinct compound ion-redundancy as a result of the high fragmentation by the electron impact ionization. Compounds in GC-MS can be resolved by taking advantage of the multivariate nature of GC-MS data by applying multivariate resolution methods. However, multivariate methods have to be applied in small regions of the chromatogram, and therefore chromatograms are segmented prior to the application of the algorithms...
October 29, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27825712/untargeted-metabolomic-analysis-of-human-serum-samples-associated-with-exposure-levels-of-persistent-organic-pollutants-indicate-important-perturbations-in-sphingolipids-and-glycerophospholipids-levels
#20
Daniel Carrizo, Olivier P Chevallier, Jayne V Woodside, Sarah F Brennan, Marie M Cantwell, Geraldine Cuskelly, Christopher T Elliott
Persistent organic pollutants (POPs) are distributed globally and are associated with adverse health effects in humans. A study combining gas chromatography-mass spectrometry (GC-MS), high resolution mass spectrometry (UPLC-QTof-MS) and chemometrics for the analysis of adult human serum samples was undertaken. Levels of serum POPs found were in the low range of what has been reported in similar populations across Europe (median 33.84 p, p'-DDE, 3.02 HCB, 83.55 β-HCH, 246.62 PCBs ng/g lipids). Results indicated that compounds concentrations were significantly different between the two groups of POPs exposure (high vs low) and classes (DDE, β-HCH, HCB, PCBs)...
November 5, 2016: Chemosphere
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