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https://www.readbyqxmd.com/read/29224138/quantification-of-global-dna-methylation-levels-by-mass-spectrometry
#1
Agustin F Fernandez, Luis Valledor, Fernando Vallejo, Maria Jesús Cañal, Mario F Fraga
Global DNA methylation was classically considered the relative percentage of 5-methylcysine (5mC) with respect to total cytosine (C). Early approaches were based on the use of high-performance separation technologies and UV detection. However, the recent development of protocols using mass spectrometry for the detection has increased sensibility and permitted the precise identification of peak compounds based on their molecular masses. This allows work to be conducted with much less genomic DNA starting material and also to quantify 5-hydroxymethyl-cytosine (5hmC), a recently identified form of methylated cytosine that could play an important role in active DNA demethylation...
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/29223892/liquid-chromatography-quadrupole-time-of-flight-mass-spectrometry-determination-of-six-pharmaceuticals-in-vegetal-biota-uptake-study-in-lavandula-dentata
#2
Sofía Barreales-Suárez, Manuel Callejón-Mochón, Stéphane Azoulay, Miguel Ángel Bello-López, Rut Fernández-Torres
A procedure based on microwave assisted extraction for the determination of 6 pharmaceuticals in samples of Lavandula dentata, Salicornia ramosissima and Juncus sp. by liquid chromatography-quadrupole time of flight mass spectrometry (LC-QTOF/MS) was optimized and validated. Best results were obtained using microwave assisted extraction of 1.0g of homogeneous lyophilized samples and 5mL of a mixture ACN:H2O (1:1 v/v) as extracting solvent. Analytical recoveries ranged from 60 to 107% with relative standard deviation (RSD) lower than 15%...
December 6, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29223812/could-saponins-be-used-to-enhance-bioremediation-of-polycyclic-aromatic-hydrocarbons-in-aged-contaminated-soils
#3
Marie Davin, Amandine Starren, Magali Deleu, Georges Lognay, Gilles Colinet, Marie-Laure Fauconnier
Polycyclic aromatic hydrocarbons (PAH) are persistent organic compounds of major concern that tend to accumulate in the environment, threatening ecosystems and health. Brownfields represent an important tank for PAHs and require remediation. Researches to develop bioremediation and phytoremediation techniques are being conducted as alternatives to environmentally aggressive, expensive and often disruptive soil remediation strategies. The objectives of the present study were to investigate the potential of saponins (natural surfactants) as extracting agents and as bioremediation enhancers on an aged-contaminated soil...
December 1, 2017: Chemosphere
https://www.readbyqxmd.com/read/29223758/biosynthesis-and-structural-characterization-of-polyhydroxyalkanoates-produced-by-pseudomonas-aeruginosa-atcc-27853-from-long-odd-chain-fatty-acids
#4
Giuseppe Impallomeni, Alberto Ballistreri, Giovanni M Carnemolla, Maria G Rizzo, Marco S Nicolò, Salvatore P P Guglielmino
Pseudomonas aeruginosa ATCC 27853 was cultured on media containing long odd-chain fatty acids. Heptadecanoic, nonadecanoic, and heneicosanoic acids sustained cell growth and resulted in polyhydroxyalkanoate (PHA) accumulation when culturing was conducted under nitrogen starvation conditions. No PHA was produced using a complete or magnesium-deprived medium. The isolated polyesters were characterized by gas chromatography and liquid chromatography-electrospray ionization mass spectrometry (ESI-MS) of methanolyzed samples, 1H and 13C NMR spectroscopy, gel permeation chromatography, ESI MS of partially pyrolyzed samples, and differential scanning calorimetry...
December 6, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/29223498/heparin-fibronectin-interactions-in-the-development-of-extracellular-matrix-insolubility
#5
Irene Raitman, Mia L Huang, Selwyn A Williams, Benjamin Friedman, Kamil Godula, Jean E Schwarzbauer
During extracellular matrix (ECM) assembly, fibronectin (FN) fibrils are irreversibly converted into a detergent-insoluble form which, through FN's multi-domain structure, can interact with collagens, matricellular proteins, and growth factors to build a definitive matrix. FN also has heparin/heparan sulfate (HS) binding sites. Using HS-deficient CHO cells, we show that the addition of soluble heparin significantly increased the amount of FN matrix that these cells assemble. Sulfated HS glycosaminoglycan (GAG) mimetics similarly increased FN assembly and demonstrated a dependence on GAG sulfation...
December 6, 2017: Matrix Biology: Journal of the International Society for Matrix Biology
https://www.readbyqxmd.com/read/29223449/anti-hsv-2-activity-of-peganum-harmala-l-and-isolation-of-the-active-compound
#6
Roudaina Benzekri, Lamjed Bouslama, Adele Papetti, Majdi Hammami, Abderrazak Smaoui, Ferid Limam
Genital herpes is a sexually transmitted disease caused by herpes simplex virus type 2 (HSV-2). Nucleoside analogues such as acyclovir (ACV) are the usual therapy for treating HSV infection. However, the overuse of this drug has led to the emergence of resistant strains. Therefore, the search for new alternative or complementary molecules to overcome this obstacle is needed. In this objective, Peganum harmala was investigated for its HSV-2 activity. The organic extracts of the different plant organs were evaluated for their cytotoxicity on Vero cells by the MTT test and anti HSV-2 activity by plaque reduction assay...
December 6, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/29223322/systemic-administration-of-epothilone-d-improves-functional-recovery-of-walking-after-rat-spinal-cord-contusion-injury
#7
Jörg Ruschel, Frank Bradke
Central nervous system (CNS) injuries cause permanent impairments of sensorimotor functions as mature neurons fail to regenerate their severed axons. The poor intrinsic growth capacity of adult CNS neurons and the formation of an inhibitory lesion scar are key impediments to axon regeneration. Systemic administration of the microtubule stabilizing agent epothilone B promotes axon regeneration and recovery of motor function by activating the intrinsic axonal growth machinery and by reducing the inhibitory fibrotic lesion scar...
December 6, 2017: Experimental Neurology
https://www.readbyqxmd.com/read/29223179/intra-and-inter-specific-variation-in-alarm-pheromone-produced-by-solenopsis-fire-ants
#8
L Hu, R R Balusu, W-Q Zhang, O S Ajayi, Y-Y Lu, R-S Zeng, H Y Fadamiro, L Chen
Some fire ants of the genus Solenopsis have become invasive species in the southern United States displacing native species by competition. Although the displacement pattern seems clear, the mechanisms underlying competitive advantage remain unclear. The ability of ant workers to produce relatively larger amount of alarm pheromone may correspond to relative greater fitness among sympatric fire ant species. Here we report on quantitative intra-specific (i.e. inter-caste) and inter-specific differences of alarm pheromone component, 2-ethyl-3,6-dimethylpyrazine (2E36DMP), for several fire ant species...
December 10, 2017: Bulletin of Entomological Research
https://www.readbyqxmd.com/read/29223161/cell-free-expression-purification-and-characterization-of-the-functional-%C3%AE-2-adrenergic-receptor-for-multianalyte-detection-of-%C3%AE-agonists
#9
Jian Wang, Yuan Liu, Junhua Zhang, Zhengzheng Han, Wei Wang, Yang Liu, Dong Wei, Wei Huang
Large-scale expression of β2-adrenergic receptor (β2-AR) in functional form is necessary for establishment of receptor assays for detecting illegally abused β-adrenergic agonists (β-agonists). Cell-based heterologous expression systems have manycritical difficulties in synthesizing this membrane protein, such as low protein yields and aberrant folding. To overcome these challenges, the main objective of the present work was to synthesize large amounts of functional β2-AR in a cell-free system based on Escherichia coli extracts...
November 2017: Biochemistry. Biokhimii︠a︡
https://www.readbyqxmd.com/read/29223157/self-organization-of-recombinant-membrane-porin-ompf-from-yersinia-pseudotuberculosis-in-aqueous-environments
#10
E V Sidorin, V A Khomenko, N Yu Kim, P S Dmitrenok, A M Stenkova, O D Novikova, T F Solov'eva
Recombinant porin OmpF (an integral protein of bacterial outer membrane) from Yersinia pseudotuberculosis was synthesized in Escherichia coli cells as inclusion bodies. By combining the methods of anion-exchange and gel filtration chromatographies, recombinant OmpF (rOmpF) was isolated as an individual protein in its denatured state, and its characteristic properties (molecular mass, N-terminal amino acid sequence, and hydrodynamic radius of the protein in 8 M urea solution) were determined. According to the data of gel filtration, dynamic light scattering, optical spectroscopy, and binding of the hydrophobic fluorescent probe 8-anilino-1-naphthalenesulfonic acid, the rOmpF is fully unfolded in 8 M urea and exists in random coil conformation...
November 2017: Biochemistry. Biokhimii︠a︡
https://www.readbyqxmd.com/read/29223155/recombinant-human-erythropoietin-with-additional-processable-protein-domains-purification-of-protein-synthesized-in-escherichia-coli-heterologous-expression-system
#11
T M Grunina, A V Demidenko, A M Lyaschuk, M S Poponova, Z M Galushkina, L A Soboleva, S A Cherepushkin, N B Polyakov, D A Grumov, A I Solovyev, V G Zhukhovitsky, I S Boksha, M E Subbotina, A V Gromov, V G Lunin, A S Karyagina
Three variants of human recombinant erythropoietin (rhEPO) with additional N-terminal protein domains were obtained by synthesis in an Escherichia coli heterologous expression system. These domains included (i) maltose-binding protein (MBP), (ii) MBP with six histidine residues (6His) in N-terminal position, (iii) s-tag (15-a.a. oligopeptide derived from bovine pancreatic ribonuclease A) with N-terminal 6His. Both variants of the chimeric protein containing MBP domain were prone to aggregation under nondenaturing conditions, and further purification of EPO after the domain cleavage by enterokinase proved to be impossible...
November 2017: Biochemistry. Biokhimii︠a︡
https://www.readbyqxmd.com/read/29223063/phytochemical-study-of-the-trunk-bark-of-citharexylum-spinosum-l-growing-in-tunisia-isolation-and-structure-elucidation-of-iridoid-glycosides
#12
Ilyes Saidi, Pierre Waffo-Téguo, Asma E L Ayeb-Zakhama, Fethia Harzallah-Skhiri, Axel Marchal, Hichem Ben Jannet
A phytochemical investigation of the trunk bark ethyl acetate extract of Citharexylum spinosum L. has led to the isolation of four previously undescribed iridoid glycosides, tunispinosides A-D, and five known phenylethanoid glycosides, verbascoside, leucosceptoside A, martynoside, isoverbascoside and plantainoside C, together with 4-hydroxy-2,6-dimethoxyphenyl 6'-O-vanilloyl-β-D-glucopyranoside, two 8,3'-neolignan glycosides, plucheosides D1-D2, coniferyl aldehyde, vanillic acid, syringic acid, ferulic acid and tyrosol...
December 6, 2017: Phytochemistry
https://www.readbyqxmd.com/read/29223060/recent-advances-in-lipid-separations-and-structural-elucidation-using-mass-spectrometry-combined-with-ion-mobility-spectrometry-ion-molecule-reactions-and-fragmentation-approaches
#13
REVIEW
Xueyun Zheng, Richard D Smith, Erin S Baker
Lipids are a vital class of molecules that play important and varied roles in biological processes, however, fully understanding these roles is extremely difficult due to the immense number and diversity of possible lipid species. While recent advances in chromatography and high resolution mass spectrometry have greatly progressed knowledge about distinct lipid species and functions, effectively separating many lipids still remains problematic. Isomeric lipids have made lipid characterization especially difficult and occur due to subclasses having the same chemical composition, or species having multiple acyl chain connectivities (sn-1, sn-2, or sn-3), double bond positions and orientations (cis or trans), and functional group stereochemistries (R versus S)...
December 6, 2017: Current Opinion in Chemical Biology
https://www.readbyqxmd.com/read/29223050/a-simple-rapid-and-stability-indicating-validated-method-for-quantification-of-lamotrigine-in-human-plasma-and-dry-plasma-spot-using-lc-esi-ms-ms-application-in-clinical-study
#14
Kuldeep Kumar Namdev, Jaya Dwivedi, Deepak Chandra Chilkoti, Swapnil Sharma
Lamotrigine (LTZ) is a phenyltriazine derivative which belongs to anti-epileptic drugs (AEDs) class and prescribed as mono- or adjunctive-therapy in treatment of epilepsy. Therapeutic drug monitoring (TDM) of AEDs provides a valid clinical tool in optimization of overall therapy. However, TDM is challenging due to the high biological samples (plasma/blood) storage/shipment costs and the limited availability of laboratories providing TDM services. Sampling in the form of dry plasma spot (DPS) or dry blood spot (DBS) are suitable alternative to overcome these issues...
December 1, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29223049/determination-of-blood-concentrations-of-main-active-compounds-in-zi-cao-cheng-qi-decoction-and-their-total-plasma-protein-binding-rates-based-on-hollow-fiber-liquid-phase-microextraction-coupled-with-high-performance-liquid-chromatography
#15
Miaomiao Li, Xuan Chen, Shuang Hu, Runqin Wang, Xiaoli Peng, Xiaohong Bai
Oil-in-salt hollow fiber liquid phase microextraction coupled with high performance liquid chromatography ultraviolet detection (HPLC-UV) was developed for determination of the blood concentrations of the main active compounds, hesperidin, honokiol, shikonin, magnolol, emodin and β,β'-dimethylacrylshikonin, after oral administration of Zi-Cao-Cheng-Qi decoction (ZCCQD) and their total plasma protein binding rates. In the procedure, a hollow fiber segment was immersed in organic solvent to fill the solvent in the fiber lumen and wall pore, and then the fiber was immersed into sodium chloride solution to cover a thin salt membrane on the fiber wall pore filling organic solvent...
December 2, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29223048/extraction-protocol-and-liquid-chromatography-tandem-mass-spectrometry-method-for-determining-micelle-entrapped-paclitaxel-at-the-cellular-and-subcellular-levels-application-to-a-cellular-uptake-and-distribution-study
#16
Nan Zheng, Bin Lian, Wenwen Du, Guobing Xu, Jiafu Ji
Paclitaxel-loaded polymeric micelles (PTX-PM) are commonly used as tumor-targeted nanocarriers and display outstanding antitumor features in clinic, but its accumulation and distribution in vitro are lack of investigation. It is probably due to the complex micellar system and its low concentration at the cellular or subcellular levels. In this study, we developed an improved extraction method, which was a combination of mechanical disruption and liquid-liquid extraction (LLE), to extract the total PTX from micelles in the cell lysate and subcellular compartments...
December 6, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29223046/cohort-friendly-protocol-for-a-sensitive-and-fast-method-for-trihalomethanes-in-urine-using-gas-chromatography-triple-quadrupole-mass-spectrometry
#17
Pantelis Charisiadis, Konstantinos C Makris
A cohort-friendly biomonitoring protocol has been developed for measuring biomarkers of exposure to disinfection by-products (trihalomethanes, THM) in urine using small initial volume (3mL) and short analysis time (∼10min) that facilitates the throughput of a large number of samples. The objective of this study was to optimise a cohort-friendly biomonitoring protocol for the determination of four THM analytes in human urine using gas chromatography coupled with triple quadrupole mass spectrometry (GC-QqQ-MS/MS)...
December 6, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29223045/investigation-of-antioxidant-ability-of-grape-seeds-extract-to-prevent-oxidatively-induced-dna-damage-by-gas-chromatography-tandem-mass-spectrometry
#18
Önder Aybastıer, Sam Dawbaa, Cevdet Demir
Phenolic compounds have been studied elaborately for their efficacy to improve health and to protect against a wide variety of diseases. Herein this study, different analysis methods were implemented to evaluate the antioxidant properties of catechin and cyanidin using their standard substances and as they found in the grape seeds extracts. Total phenol contents were 107.39±8.94mg GAE/g dw of grape seeds for grape seed extract (GSE) and 218.32±10.66mg GAE/g dw of grape seeds for acid-hydrolyzed grape seed extract (AcGSE)...
December 6, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29223014/differentiation-of-dry-cured-hams-from-different-processing-methods-by-means-of-volatile-compounds-physico-chemical-and-sensory-analysis
#19
Sandra Petričević, Nives Marušić Radovčić, Katarina Lukić, Eddy Listeš, Helga Medić
The aim of this study was to characterize dry-cured hams from four different processing methods (differences in primary leg treatment, salting and smoking phase). Volatile compounds were isolated by using headspace-solid phase microextraction and analysed by gas chromatography/mass spectrometry (GC/MS). Samples were also evaluated by sensory and physico-chemical characteristics (moisture, protein, fat and NaCl content, aw, colour). 149 volatile compounds of dry-cured hams were identified and 15 of them were quantified...
December 5, 2017: Meat Science
https://www.readbyqxmd.com/read/29222888/common-food-antimicrobials-effects-on-cellular-inflammation-and-oxidative-damage-and-their-estimated-occurrence-in-singapore
#20
Claudine Loong, Shin Yih Tsen, Xing Lin Ho, Muhammed Faiz B Raman, Wai Mun Loke
BACKGROUND AND OBJECTIVES: The prevalence and potential health effects of common food antimicrobials in processed foods and beverages are relatively unknown in Singapore. The occurrence of chemical antimicrobials in processed foods and beverages and their effects on inflammation and oxidative stress in vitro were examined. METHODS AND STUDY DESIGN: The occurrence of antimicrobials in 1605 processed food and 359 beverage items were examined by surveying the ingredients on the product labels...
2018: Asia Pacific Journal of Clinical Nutrition
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