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https://www.readbyqxmd.com/read/29169203/dissipation-residues-and-risk-assessment-of-spirotetramat-and-its-four-metabolites-in-citrus-and-soil-under-field-conditions-by-lc-ms-ms
#1
Qingtao Zhang, Yuling Chen, Shouyi Wang, Yurong Yu, Ping Lu, Deyu Hu, Zaihui Yang
A modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for the simultaneous determination of spirotetramat and its four metabolite residues in citrus, peel, pulp and soil was developed and validated by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The samples were extracted with acetonitrile (1%, glacial acetic acid, v/v) and purified using primary secondary amine and octadecylsilane. The limit of detection was 0.01-0.13 mg/kg, whereas that of quantification was 0.02-0...
November 23, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29169114/evaluation-of-antiparkinson-activity-of-ptupb-by-measuring-dopamine-and-its-metabolites-in-drosophila-melanogaster-lc-ms-ms-method-development
#2
Navya Lakkappa, Praveen T Krishnamurthy, Karthik Yamjala, Sung Hee Hwang, Bruce D Hammock, B Babu
Soluble epoxide hydrolase (sEH) inhibition is reported to elevate endogenous epoxyeicosatrienoic acids (EET's), which are known to play an important role in neuroprotection by inhibiting oxidative stress and neuroinflammation. In the present study, PTUPB, a dual inhibitor of sEH and COX-2, has been tested for its antiparkinson activity against rotenone (ROT) induced neurodegeneration in Drosophila model of Parkinson's disease (PD). To determine the efficacy and brain bioavailability of PTUPB a simple, rapid and sensitive LC-MS/MS method was developed and validated for the estimation of PTUPB (Method-I), dopamine (DA) and its metabolites (Method-II) in fly head...
November 16, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29169112/analysis-of-unbound-plasma-concentration-of-oxcarbazepine-and-the-10-hydroxycarbazepine-enantiomers-by-liquid-chromatography-with-tandem-mass-spectrometry-in-healthy-volunteers
#3
Natalícia de Jesus Antunes, Lauro Wichert-Ana, Eduardo Barbosa Coelho, Oscar Della Pasqua, Veriano Alexandre Junior, Osvaldo Massaiti Takayanagui, Maria Paula Marques, Vera Lucia Lanchote
This study describes the development and validation of a method for the analysis of unbound plasma concentrations of oxcarbazepine (OXC) and of the enantiomers of its active metabolite 10-hydroxycarbazepine (MHD) [S-(+)- and R-(-)-MHD] using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Additionally, the free fraction of the drug is described in healthy volunteers (n=12) after the oral administration of 300mg OXC/12h for 5days. Plasma aliquots of 200μL were submitted to ultrafiltration procedure and 50μL of the ultrafiltrate were extracted with a mixture of tert-butyl methyl ether:dichloromethane (2:1, v/v)...
November 20, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29169111/identification-of-phenolic-components-via-lc-ms-analysis-and-biological-activities-of-two-centaurea-species-c-drabifolia-subsp-drabifolia-and-c-lycopifolia
#4
Gokhan Zengin, Dimitrina Zheleva-Dimitrova, Reneta Gevrenova, Paraskev Nedialkov, Andrei Mocan, Ana Ćirić, Jasmina Glamočlija, Marina Soković, Abdurrahman Aktumsek, M Fawzi Mahomoodally
The Centaurea genus has great potential in traditional systems and has attracted much interest in the design of novel drug formulations. The present study was focused on the chemical fingerprints and biological properties of Centaurea drabifolia subsp. drabifolia and Centaurea lycopifolia extracts. Spectrophotometric and LC-MS techniques were used to establish the chemical profiles of the studied extracts. Enzyme inhibitory potential was assessed against key enzymes linked to global health problems, namely neurodegenerative diseases (acetylcholinesterase), pigmentation (tyrosinase), and diabetes (α-amylase and α-glucosidase)...
November 20, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29169110/disorder-of-gut-amino-acids-metabolism-during-ckd-progression-is-related-with-gut-microbiota-dysbiosis-and-metagenome-change
#5
Yang Liu, Jianping Li, Jingao Yu, Yingyi Wang, Jingbo Lu, Er-Xin Shang, Zhenhua Zhu, Jianming Guo, Jinao Duan
Chronic kidney disease (CKD) is a worldwide public health problem. Uremic retention solutes such as indoxyl sulfate (IS) and p-cresyl sulfate (PCS) are accumulated in CKD patients and are associated with the incidence of CKD progression. Amino acids are the major precursors of uremic retention solutes in gut. The dynamic change of amino acid metabolism in the gut during CKD progression has not been reported previously. In this paper, we studied the dynamic change of gut IS/PCS precursor and amino acid metabolism profile during CKD progression in 5/6 nephrectomized (5/6Nx) rats model...
November 15, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29168931/plasma-concentrations-of-cytisine-a-commercially-available-plant-based-alkaloid-in-healthy-adult-smokers-taking-recommended-doses-for-smoking-cessation
#6
Soo Hee Jeong, Janie Sheridan, David Newcombe, Malcolm Tingle
Cytisine is a plant alkaloid that is a partial agonist for the α4β2-nAChRs and is used as an aid to smoking cessation. To date, there are no published data on cytisine concentrations in humans following multiple dosing. The aim of this study was to determine cytisine plasma concentrations after taking recommended doses for smoking cessation and to report on adverse effects. Subjects (n = 10) were instructed to follow the 25-day standard dosing regimen of cytisine. Blood was collected at 0, 2, 4, 8 and 10 hours on day 1 then on subsequent visits (days 2, 3, 4, 6, 13, 14, 17, 18, 21, 22, 25 and 26) to measure plasma cytisine concentrations...
November 23, 2017: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/29168748/variety-and-dynamics-of-proteoforms-in-the-human-proteome-aspects-of-markers-for-hepatocellular-carcinoma
#7
Stanislav Naryzhny, Victor Zgoda, Artur Kopylov, Elena Petrenko, Olga Kleist, Аlexander Archakov
We have previously developed an approach, where two-dimensional gel electrophoresis (2DE) was used, followed by sectional analysis of the whole gel using high-resolution nano-liquid chromatography-mass spectrometry (ESI LC-MS/MS). In this study, we applied this approach on the panoramic analysis of proteins and their proteoforms from normal (liver) and cancer (HepG2) cells. This allowed us to detect, in a single proteome, about 20,000 proteoforms coded by more than 4000 genes. A set of 3D-graphs showing distribution of these proteoforms in 2DE maps (profiles) was generated...
November 23, 2017: Proteomes
https://www.readbyqxmd.com/read/29168743/synthesis-and-anticandidal-activity-evaluation-of-new-benzimidazole-thiazole-derivatives
#8
Zafer Asım Kaplancıklı, Serkan Levent, Derya Osmaniye, Begüm Nurpelin Sağlık, Ulviye Acar Çevik, Betül Kaya Çavuşoğlu, Yusuf Özkay, Sinem Ilgın
Azole-based antifungal agents constitute one of the important classes of antifungal drugs. Hence, in the present work, 12 new benzimidazole-thiazole derivatives 3a-3l were synthesized to evaluate their anticandidal activity against C.albicans, C.glabrata, C.krusei, and C.parapsilopsis. The structures of the newly synthesized compounds 3a-3l were confirmed by IR, ¹H-NMR, (13)C-NMR, and ESI-MS spectroscopic methods. ADME parameters of synthesized compounds 3a-3l were predicted by an in-slico study and it was determined that all synthesized compounds may have a good pharmacokinetic profile...
November 23, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29168212/serum-25-hydroxyvitamin-d3-levels-of-one-month-old-term-infants-in-tokyo-using-liquid-chromatography-tandem-mass-spectrometry
#9
Kaori Hara, Kazushige Ikeda, Yuhei Koyama, Yasuhiro Wada, Tomonobu Hasegawa
The major circulating form of vitamin D, 25 hydroxyvitamin D (25(OH)D), is usually measured by radioimmunoassay (RIA) or competitive protein binding assay. However, studies have shown discrepancies between assays, mainly due to cross reactivity with vitamin D metabolites (1). Liquid chromatography tandem mass spectrometry (LC-MS/MS) has now become the gold standard for measuring serum 25(OH)D levels (2). This article is protected by copyright. All rights reserved.
November 23, 2017: Acta Paediatrica
https://www.readbyqxmd.com/read/29167526/phospholipase-a2-responsive-phosphate-micelle-loaded-ucnps-for-bioimaging-of-prostate-cancer-cells
#10
Mirkomil Sharipov, Salah M Tawfik, Zayakhuu Gerelkhuu, Bui The Huy, Yong-Ill Lee
We report the effective synthesis of biocompatible upconversion nanoparticles (UCNP)-loaded phosphate micelles and successful delivery of UCNPs to prostate cancer cells via secreted phospholipase A2 (sPLA-2) enzyme cleavage of the loaded micelles for the first time. The activity of the (sPLA-2) enzyme toward the synthesized micelles was investigated and confirmed by LC-MS. TEM results showed that the micelles have a size distribution of 80 to 150 nm, whereas UCNP-loaded micelles range from 200 to 350 nm, indicating the successful loading of UCNPs...
November 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29166834/the-entomopathogenic-fungus-metarhizium-robertsii-communicates-with-the-insect-host-galleria-mellonella-during-infection
#11
Krishnendu Mukherjee, Andreas Vilcinskas
Parasitic fungi are the only pathogens that can infect insect hosts directly through their proteinaceous exoskeleton. Penetration of the cuticle requires the release of fungal enzymes, including proteinases, which act as virulence factors. Insects can sense fungal infections and activate innate immune responses, including the synthesis of antifungal peptides and proteinase inhibitors that neutralize the incoming proteinases. This well-studied host response is epigenetically regulated by histone acetylation/deacetylation...
November 23, 2017: Virulence
https://www.readbyqxmd.com/read/29166575/chemical-characterization-and-pharmacological-assessment-of-cashew-gum-extract-anacardium-occidentale-l-polysaccharide-free
#12
Daiany Priscilla Bueno da Silva, Iziara Ferreira Florentino, Lorrane Kelle da Silva Moreira, Adriane Ferreira Brito, Verônica Vale Carvalho, Géssica Adriana Vasconcelos, Boniek Gontijo Vaz, Marcus Antônio Pereira-Junior, Kátia Flávia Fernandes, Elson Alves Costa
ETHNOPHARMACOLOGICAL RELEVANCE: The cashew gum (Anacardium occidentale L.) is used in Brazilian traditional medicine in the treatment of inflammatory conditions, asthma, diabetes, and gastrointestinal disturbs. AIM OF THE STUDY: The present study was aimed the chemical characterization and the investigation of the antinociceptive and anti-inflammatory activities of cashew gum aqueous extract without the presence of polysaccharides in its composition (CGE). MATERIALS AND METHODS: The CGE was obtained after precipitation and removal of polysaccharides using acetone...
November 19, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/29165829/simultaneous-determination-and-method-validation-of-clethodim-and-its-metabolites-clethodim-sulfoxide-and-clethodim-sulfone-in-tobacco-by-lc-ms-ms
#13
Fei Wang, Guoqiang Yang, Jin Xu, Weiwei Yu, Lihong Shi, Song Zeng, Lingzhu Chen, Deyu Hu, Kankan Zhang
A simple method was developed and validated for the simultaneous determination of clethodim, clethodim sulfoxide, and clethodim sulfone in soil and tobacco by liquid chromatography with tandem mass spectrometry. The three target compounds were extracted from tobacco and soil with acetonitrile, and the extracts were purified using octadecyl silane. The proposed method showed satisfactory linearity (R(2) ≥ 0.9973) for the target compounds. The limits of detection and quantitation of the three analytes in all matrices were 0...
November 22, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29165327/effects-of-dl-3-n-butylphthalide-on-cerebral-ischemia-infarction-in-rat-model-by-mass-spectrometry-imaging
#14
Run-Zhe Liu, Chao-Xin Fan, Zhi-Lin Zhang, Xin Zhao, Yi Sun, Hui-Hui Liu, Zong-Xiu Nie, Xiao-Ping Pu
Dl-3-n-butylphthalide (NBP) is a drug that is used in the treatment of ischaemic stroke. However, to the best of our knowledge, there are no systematic studies investigating the effects of dl-3-n-butylphtalide on the brain metabolism of small molecules. In this study, we first investigated the effects of dl-3-n-butylphthalide on the spatial distribution of small molecules in the brains of rats with permanent middle cerebral artery occlusion (pMCAO) using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) imaging...
November 22, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/29164889/comparison-of-quantitative-mass-spectrometry-platforms-for-monitoring-kinase-atp-probe-uptake-in-lung-cancer
#15
Melissa A Hoffman, Bin Fang, Eric B Haura, Uwe Rix, John M Koomen
Recent developments in instrumentation and bioinformatics have led to new quantitative mass spectrometry platforms including LC-MS/MS with data-independent acquisition (DIA) and targeted analysis using parallel reaction monitoring mass spectrometry (LC-PRM), which provide alternatives to well-established methods, such as LC-MS/MS with data-dependent acquisition (DDA) and targeted analysis using multiple reaction monitoring mass spectrometry (LC-MRM). These tools have been used to identify signaling perturbations in lung cancers and other malignancies, supporting the development of effective kinase inhibitors and, more recently, providing insights into therapeutic resistance mechanisms and drug repurposing opportunities...
November 22, 2017: Journal of Proteome Research
https://www.readbyqxmd.com/read/29164873/plasma-protein-turnover-rates-in-rats-using-stable-isotope-labeling-global-proteomics-and-activity-based-protein-profiling
#16
Jordan Ned Smith, Kimberly J Tyrrell, Joshua R Hansen, Dennis George Thomas, Taylor A Murphree, Anil K Shukla, Teresa Luders, James M Madden, YunYing Li, Aaron T Wright, Paul D Piehowski
Protein turnover is important for general health on cellular and organism scales providing a strategy to replace old, damaged, or dysfunctional proteins. Protein turnover also informs of biomarker kinetics, as a better understanding of synthesis and degradation of proteins increases the clinical utility of biomarkers. Here, turnover rates of plasma proteins in rats were measured in vivo using a pulse-chase stable isotope labeling experiment. During the pulse, rats (n=5) were fed 13C6-labeled lysine ("heavy") feed for 23 days to label proteins...
November 22, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29164517/the-mycoestrogen-zearalenone-in-portuguese-flowing-waters-and-its-potential-environmental-impact
#17
Célia S M Laranjeiro, Liliana João Gatões da Silva, André M P T Pereira, Angelina Pena, Celeste M Lino
This study provides the first environmental risk assessment (ERA) for zearalenone (ZEN), the only known mycoestrogen, based on a broad-scale investigation on its occurrence in rivers and creeks from Portugal. Water sample filtration and immunoaffinity columns (IAC) clean-up followed by liquid chromatograph with tandem mass spectrometry (LC/MS (n) ) provided an analytical method with good analytical performance. ZEN levels were determined for seven Portuguese rivers and one creek, during two different seasons, in a total of 38 samples collected upstream wastewater treatment plants (WWTPs)...
November 21, 2017: Mycotoxin Research
https://www.readbyqxmd.com/read/29164282/analysis-of-bronopol-2-bromo-2-nitropropan-1-3-diol-residues-in-rice-oryza-sativa-l-by-spe-using-bond-elut-plexa-and-liquid-chromatography-tandem-mass-spectrometry
#18
Shuang-Shuang Chai, Mei-Ling Qin, You-Ning Ma, Huan-Huan Gao, Qiao He, Han-Tong Zhang
A novel method has been developed for the direct, sensitive, and rapid detection of bronopol in rice using a simple solid-phase extraction (SPE) procedure followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), with electrospray ionization (ESI). Bronopol was stable under acidic conditions, and an acidic environment was thus needed before sample loading to ensure the stability of bronopol. Rice extracts containing bronopol were pretreated using a hydrophilic-lipophilic balanced (Bond Elut Plexa) cartridge to reduce the matrix effect...
November 21, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29164281/monitoring-of-post-mortem-changes-of-saliva-n-glycosylation-by-nano-lc-ms
#19
Bum Jin Kim, Chanyoung Han, Hantae Moon, Joseph Kwon, Ik-Soon Jang, Si-Keun Lim, Ki-Won Park, Jong-Soon Choi, Hyun Joo An
The estimation of post-mortem interval (PMI) is a crucial part for investigations of crime and untimely deaths in forensic science. However, standard methods of PMI estimation are easily confounded by extenuating circumstances and/or environmental factors. Therefore, a panel of PMI markers obtained from a more acceptable and accurate method is necessary to definitely determine time of death. Saliva, one of the vital fluids encountered at crime scenes, contains various glycoproteins that are highly affected by biochemical environment...
November 21, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29163566/cultivar-diversity-of-grape-skin-polyphenol-composition-and-changes-in-response-to-drought-investigated-by-lc-ms-based-metabolomics
#20
Lucie Pinasseau, Anna Vallverdú-Queralt, Arnaud Verbaere, Maryline Roques, Emmanuelle Meudec, Loïc Le Cunff, Jean-Pierre Péros, Agnès Ageorges, Nicolas Sommerer, Jean-Claude Boulet, Nancy Terrier, Véronique Cheynier
Phenolic compounds represent a large family of plant secondary metabolites, essential for the quality of grape and wine and playing a major role in plant defense against biotic and abiotic stresses. Phenolic composition is genetically driven and greatly affected by environmental factors, including water stress. A major challenge for breeding of grapevine cultivars adapted to climate change and with high potential for wine-making is to dissect the complex plant metabolic response involved in adaptation mechanisms...
2017: Frontiers in Plant Science
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