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https://www.readbyqxmd.com/read/28336968/new-cofactors-and-inhibitors-for-a-dna-cleaving-dnazyme-superoxide-anion-and-hydrogen-peroxide-mediated-an-oxidative-cleavage-process
#1
Yanhong Sun, Rulong Ma, Shijin Wang, Guiying Li, Yongjie Sheng, Hongyue Rui, Jin Zhang, Jiacui Xu, Dazhi Jiang
Herein, we investigated the effects of new cofactors and inhibitors on an oxidative cleavage of DNA catalysis, known as a pistol-like DNAzyme (PLDz), to discuss its catalytic mechanism. PLDz performed its catalytic activity in the presence of ascorbic acid (AA), in which Cu(2+) promoted, whereas Fe(2+) significantly inhibited the catalytic function. Since Fe(2+)/AA-generated hydroxyl radicals are efficient on DNA damage, implying that oxidative cleavage of PLDz had no relation with hydroxyl radical. Subsequently, we used Fe(2+)/H2O2 and Cu(2+)/H2O2 to identify the role of hydroxyl radicals in PLDz catalysis...
March 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28303227/analysis-of-cordyceps-by-multi-column-liquid-chromatography
#2
Zhengming Qian, Shaoping Li
Cordyceps is a famous traditional Chinese medicine (TCM) that has been used in China for hundreds of years. In the present study a multi-column liquid chromatography (MC-LC) system was developed for the qualitative analysis of macromolecules and micromolecules in Cordyceps. The MC-LC system includes a size exclusion pre-column, a size exclusion column (SEC) and a reversed phase column (RP) which were controlled by column-switching valves. The sample was separated by the size exclusion pre-column into two fractions (macromolecules and micromolecules)...
March 2017: Acta Pharmaceutica Sinica. B
https://www.readbyqxmd.com/read/28300194/amniotic-fluid-metabolomics-and-biochemistry-analysis-provides-novel-insights-into-the-diet-regulated-foetal-growth-in-a-pig-model
#3
Jin Wan, Fei Jiang, Jiao Zhang, Qingsong Xu, Daiwen Chen, Bing Yu, Xiangbing Mao, Jie Yu, Yuheng Luo, Jun He
Foetal loss and intrauterine growth restriction are major problems in mammals, but there are few effective ways in preventing it. Intriguingly, chitosan oligosaccharide (COS), a biomaterial derived from chitosan, can promote foetal survival and growth. Therefore, we have investigated how COS affects foetal survival and growth in a pig model. Fifty-two sows were divided into two treatment groups (n = 26) and fed either solely a control diet or a control diet that includes 100 mg/kg COS. Amniotic fluid and foetus samples from six sows that were of average body weight in each group were collected on gestation day 35...
March 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28294336/adenosine-production-by-brain-cells
#4
Edwin K Jackson, Shawn E Kotermanski, Elizabeth V Menshikova, Raghvendra K Dubey, Travis C Jackson, Patrick M Kochanek
The early release of adenosine following traumatic brain injury (TBI) suppresses seizures and brain inflammation; thus, it is important to elucidate the cellular sources of adenosine following injurious stimuli triggered by TBI so that therapeutics for enhancing the early adenosine-release response can be optimized. Using mass spectrometry with (13) C-labelled standards, we investigated in cultured rat neurons, astrocytes, and microglia the effects of oxygen-glucose deprivation (OGD; models energy failure), H2 O2 (produces oxidative stress), and glutamate (induces excitotoxicity) on intracellular and extracellular levels of 5'-AMP (adenosine precursor), adenosine, and inosine and hypoxanthine (adenosine metabolites)...
March 13, 2017: Journal of Neurochemistry
https://www.readbyqxmd.com/read/28292464/intracellular-acidification-increases-adenosine-transport-in-human-umbilical-vein-endothelial-cells
#5
Natalia Celis, Joaquín Araos, Carlos Sanhueza, Fernando Toledo, Ana R Beltrán, Fabián Pardo, Andrea Leiva, Marco A Ramírez, Luis Sobrevia
INTRODUCTION: Adenosine is taken up via human equilibrative nucleoside transporters 1 (hENT1) and 2 (hENT2) at a physiological extracellular pH (pHo ∼7.4) in human umbilical vein endothelial cells (HUVECs). Acidic pHo increases the uptake of adenosine and 5-hydroxytryptamine (5HT) via hENT4 in this cell type. However, modulation of hENT1 and hENT2 transport activity by the pHi is unknown. We investigated whether hENT1 and hENT2-adenosine transport was regulated by acidic pHi. METHODS: HUVECs loaded with a pH sensitive probe were subjected to 0...
March 2017: Placenta
https://www.readbyqxmd.com/read/28282902/lactobacillus-gasseri-pa-3-uses-the-purines-imp-inosine-and-hypoxanthine-and-reduces-their-absorption-in-rats
#6
Naruomi Yamada, Chizuru Saito-Iwamoto, Marie Nakamura, Misato Soeda, Yoshika Chiba, Hiroshi Kano, Yukio Asami
Excessive intake of purine-rich foods elevates serum levels of uric acid. Animal and fish meats contain high amounts of inosine and its related purines, and the reduction of taking those purines is crucial for the improvement of serum uric acid levels. We previously showed that Lactobacillus gasseri PA-3 (PA-3) incorporates adenosine and its related purines and that oral treatment with PA-3 reduced adenosine absorption in rats. This study investigated whether PA-3 also incorporates IMP (inosine 5'-monophosphate), inosine, and hypoxanthine, and whether it reduces their absorption in rats...
March 8, 2017: Microorganisms
https://www.readbyqxmd.com/read/28282408/the-renal-phenotype-of-allopurinol-treated-hprt-deficient-mouse
#7
Cristina Zennaro, Federica Tonon, Paola Zarattini, Milan Clai, Alessandro Corbelli, Michele Carraro, Marialaura Marchetti, Luca Ronda, Gianluca Paredi, Maria Pia Rastaldi, Riccardo Percudani
Excess of uric acid is mainly treated with xanthine oxidase (XO) inhibitors, also called uricostatics because they block the conversion of hypoxanthine and xanthine into urate. Normally, accumulation of upstream metabolites is prevented by the hypoxanthine-guanine phosphoribosyltransferase (HPRT) enzyme. The recycling pathway, however, is impaired in the presence of HPRT deficiency, as observed in Lesch-Nyhan disease. To gain insights into the consequences of purine accumulation with HPRT deficiency, we investigated the effects of the XO inhibitor allopurinol in Hprt-lacking (HPRT-/-) mice...
2017: PloS One
https://www.readbyqxmd.com/read/28273649/modeling-and-optimizing-inhibitory-activities-of-nelumbinis-folium-extract-on-xanthine-oxidase-using-response-surface-methodology
#8
Mangmang Sang, Guangyan Du, Jia Hao, Linlin Wang, Erwei Liu, Yi Zhang, Tao Wang, Xiumei Gao, Lifeng Han
Xanthine oxidase (XOD), which could oxidize hypoxanthine to xanthine and then to uric acid, is a key enzyme in the pathogenesis of hyperuricemia and also a well-known target for the drug development to treat gout. In our study, the total alkaloids of Nelumbinis folium markedly inhibited XOD activity, with IC50 value being 3.313μg/mL. UHPLC-Q-TOF-MS and 3D docking analysis indicated that roemerine was a potential active ingredient. A response surface methodology combined with central composite design experiment was further developed and validated for the optimization of the reaction conditions between the total alkaloids of Nelumbinis folium and XOD, which could be considered as a meaningful research for the development of XOD inhibitor rapidly and sensitively...
March 1, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28245094/synthesis-antimalarial-activity-in-vitro-and-docking-studies-of-novel-neolignan-derivatives
#9
Glaécia A N Pereira, Gisele C Souza, Lourivaldo S Santos, Lauro E S Barata, Carla C F Meneses, Antoniana U Krettli, Cláudio Tadeu Daniel-Ribeiro, Cláudio Nahum Alves
The absence of effective vaccines against malaria and the difficulties associated with controlling mosquito vectors has left chemotherapy as the primary control measure against malaria. However, the emergence and spread of parasite resistance to conventional antimalarial drugs result in a worrisome scenario making the search for new drugs a priority. In the present study, the activities of nine neolignan derivatives were evaluated as follows: (i) against blood forms of chloroquine-resistant Plasmodium falciparum (clone W2), using the tritiated hypoxanthine incorporation and Anti-HRPII assays; (ii) for cytotoxic activity against cultured human hepatoma cells (HepG2); and, (iii) for intermolecular interaction with the P...
February 28, 2017: Chemical Biology & Drug Design
https://www.readbyqxmd.com/read/28244322/impact-of-the-pd2spermine-chelate-on-osteosarcoma-metabolism-an-nmr-metabolomics-study
#10
Inês Lamego, M Paula M Marques, Iola F Duarte, Ana S Martins, Helena Oliveira, Ana M Gil
A metabolomics study of Pd2Spermine(Spm) on osteosarcoma MG-63 and osteoblastic HOb cells is presented to assess the impact of the potential palladium drug on cell metabolism compared with cisplatin (cDDP). Despite its higher cytotoxicity, Pd2Spm induced lower (and reversible) metabolic impact on MG-63 cells and the absence of apoptosis; conversely, it induced significant deviations in osteoblastic amino acid metabolism. However, when in combination with doxorubicin and methotrexate, Pd2Spm induced strong metabolic deviations on lipids, choline compounds, amino acids, nucleotides, and compounds related to antioxidative mechanisms (e...
March 14, 2017: Journal of Proteome Research
https://www.readbyqxmd.com/read/28243539/inhibition-of-calcineurin-by-fk506-stimulates-germinal-vesicle-breakdown-of-mouse-oocytes-in-hypoxanthine-supplemented-medium
#11
Li Wang, Yan-Hong Zhen, Xiao-Ming Liu, Jing Cao, Yan-Ling Wang, Li-Jun Huo
Calcineurin (CN) is a serine/threonine phosphatase which plays important roles in meiosis maturation in invertebrate oocytes; however, the role of CN in mouse oocytes is relatively unexplored. In this study, we examined the expression, localization and functional roles of CN in mouse oocytes and granulosa cells. The RT-PCR results showed that the β isoform of calcineurin A subunit (Cn A) expressed significantly higher than α and γ isoforms, and the expression of Cn Aβ mRNA obviously decreased in oocytes in which germinal vesicle breakdown (GVBD) occurred, while only B1 of calcineurin B subunit (Cn B) was detected in oocytes and stably expressed during oocytes maturation...
2017: PeerJ
https://www.readbyqxmd.com/read/28242449/design-and-synthesis-of-novel-adenine-fluorescence-probe-based-on-eu-iii-complexes-with-dtpa-bis-guanine-ligand
#12
Fengyun Tian, Xiaoqing Jiang, Xuekai Dou, Qiong Wu, Jun Wang, Youtao Song
A novel adenine (Ad) fluorescence probe (Eu(III)-dtpa-bis(guanine)) was designed and synthesized by improving experimental method based on the Eu(III) complex and dtpa-bis(guanine) ligand. The dtpa-bis(guanine) ligand was first synthesized by the acylation action between dtpaa and guanine (Gu), and the corresponding Eu(III) complex was successfully prepared through heat-refluxing method with dtpa-bis(guanine) ligand. As a novel fluorescence probe, the Eu(III)-dtpa-bis(guanine) complex can detect adenine (Ad) with characteristics of strong targeting, high specificity and high recognition ability...
February 24, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28238935/tryptophan-and-purine-metabolites-are-consistently-upregulated-in-the-urinary-metabolome-of-patients-diagnosed-with-gestational-diabetes-mellitus-throughout-pregnancy-a-longitudinal-metabolomics-study-of-chinese-pregnant-women-part-2
#13
Kai P Law, Ting-Li Han, Xun Mao, Hua Zhang
BACKGROUND: Gestational diabetes mellitus (GDM) is a pathological state of glucose intolerance associated with adverse pregnancy outcomes and an increased risk of developing maternal type 2 diabetes later in life. The mechanisms underlying GDM development are not fully understood. We examined the pathophysiology of GDM through comprehensive metabolic profiling of maternal urine, using participants from a longitudinal cohort of normal pregnancies and pregnancies complicated by GDM. METHODS: Based on ultra-performance liquid chromatography/hybrid quadrupole time-of-flight mass spectrometry, an untargeted metabolomics study was performed to explore the differences in the urinary metabolome of GDM cases and healthy controls over the course of pregnancy...
February 24, 2017: Clinica Chimica Acta; International Journal of Clinical Chemistry
https://www.readbyqxmd.com/read/28238512/design-and-synthesis-of-novel-potent-and-selective-hypoxanthine-analogs-as-adenosine-a1-receptor-antagonists-and-their-biological-evaluation
#14
Summon Koul, Vidya Ramdas, Dinesh A Barawkar, Yogesh B Waman, Neela Prasad, Santosh Kumar Madadi, Yogesh D Shejul, Rajesh Bonagiri, Sujay Basu, Suraj Menon, Srinivasa B Reddy, Sandhya Chaturvedi, Srinivas Rao Chennamaneni, Gaurav Bedse, Rhishikesh Thakare, Jayasagar Gundu, Sumit Chaudhary, Siddhartha De, Ashwinkumar V Meru, Venkata Palle, Anita Chugh, Kasim A Mookhtiar
Multipronged approach was used to synthesize a library of diverse C-8 cyclopentyl hypoxanthine analogs from a common intermediate III. Several potent and selective compounds were identified and evaluated for pharmacokinetic (PK) properties in Wistar rats. One of the compounds 14 with acceptable PK parameters was selected for testing in in vivo primary acute diuresis model. The compound demonstrated significant diuretic activity in this model.
February 16, 2017: Bioorganic & Medicinal Chemistry
https://www.readbyqxmd.com/read/28235996/rapid-urinary-tract-infection-diagnostics-by-surface-enhanced-raman-spectroscopy-sers-identification-and-antibiotic-susceptibilities
#15
W R Premasiri, Ying Chen, P M Williamson, D C Bandarage, C Pyles, L D Ziegler
SERS spectra of 12 bacterial strains of urinary tract infection (UTI) clinical isolates grown and enriched from urine are reported. A partial least squares-discriminant analysis (PLS-DA) classification treatment of these SERS spectra results in strain level identification with >95% sensitivity and >99% specificity. The classification model successfully identified the SERS spectra of a urine-cultured strain not used to build this statistical model. Enrichment was accomplished by a filtration and centrifugation protocol...
April 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28228507/alcohol-dehydrogenase-5-is-a-source-of-formate-for-de-novo-purine-biosynthesis-in-hepg2-cells
#16
Sajin Bae, James Chon, Martha S Field, Patrick J Stover
Background: Formate provides one-carbon units for de novo purine and thymidylate (dTMP) synthesis and is produced via both folate-dependent and folate-independent pathways. Folate-independent pathways are mediated by cytosolic alcohol dehydrogenase 5 (ADH5) and mitochondrial aldehyde dehydrogenase 2 (ALDH2), which generate formate by oxidizing formaldehyde. Formate is a potential biomarker of B-vitamin-dependent one-carbon metabolism.Objective: This study investigated the contributions of ADH5 and ALDH2 to formate production and folate-dependent de novo purine and dTMP synthesis in HepG2 cells...
February 22, 2017: Journal of Nutrition
https://www.readbyqxmd.com/read/28221022/quantitative-13-c-traces-of-glucose-fate-in-hepatitis-b-virus-infected-hepatocytes
#17
Qianfen Wan, Yulan Wang, Huiru Tang
Quantitative characterization of (13)C-labeled metabolites is an important part of the stable isotope tracing method widely used in metabolic flux analysis. Given the long relaxation time and low sensitivity of (13)C nuclei, direct measurement of (13)C-labeled metabolites using one-dimensional (13)C NMR often fails to meet the demand of metabolomics studies, especially with large numbers of samples and metabolites having low abundance. Although HSQC-based 2D NMR methods have improved sensitivity with inversion detection, they are time-consuming and thus unsuitable for high-throughput absolute quantification of (13)C-labeled metabolites...
March 6, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28219800/variations-in-gut-microbiota-and-fecal-metabolic-phenotype-associated-with-depression-by-16s-rrna-gene-sequencing-and-lc-ms-based-metabolomics
#18
Meng Yu, Hongmei Jia, Chao Zhou, Yong Yang, Yang Zhao, Maohua Yang, Zhongmei Zou
As a prevalent, life-threatening and highly recurrent psychiatric illness, depression is characterized by a wide range of pathological changes; however, its etiology remains incompletely understood. Accumulating evidence supports that gut microbiota affects not only gastrointestinal physiology but also central nervous system (CNS) function and behavior through the microbiota-gut-brain axis. To assess the impact of gut microbiota on fecal metabolic phenotype in depressive conditions, an integrated approach of 16S rRNA gene sequencing combined with ultra high-performance liquid chromatography-mass spectrometry (UHPLC-MS) based metabolomics was performed in chronic variable stress (CVS)-induced depression rat model...
February 10, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28219521/butyrate-influences-intracellular-levels-of-adenine-and-adenine-derivatives-in-the-fungus-penicillium-restrictum
#19
Christoph Zutz, Yi Ming Chiang, Bettina Faehnrich, Markus Bacher, Roland Hellinger, Bernhard Kluger, Martin Wagner, Joseph Strauss, Kathrin Rychli
Butyrate, a small fatty acid, has an important role in the colon of ruminants and mammalians including the inhibition of inflammation and the regulation of cell proliferation. There is also growing evidence that butyrate is influencing the histone structure in mammalian cells by inhibition of histone deacetylation. Butyrate shows furthermore an antimicrobial activity against fungi, yeast and bacteria, which is linked to its toxicity at a high concentration. In fungi there are indications that butyrate induces the production of secondary metabolites potentially via inhibition of histone deacetylases...
April 2017: Microbiological Research
https://www.readbyqxmd.com/read/28213225/a-melamine-based-molecularly-imprinted-sensor-for-the-determination-of-8-hydroxydeoxyguanosine-in-human-urine
#20
Neeraj Kumar, Rosy, Rajendra N Goyal
A sensitive and facile molecular imprinted sensor has been fabricated using edge plane pyrolytic graphite (EPPG) for the determination of an important oxidative DNA damage product, 8-hydroxydeoxyguanosine (8-OHdG). The molecularly imprinted polymer film was fabricated by electropolymerization of melamine in the presence of 8-OHdG, on glutaraldehyde/poly 1,5-diaminonaphthalene modified EPPG. The imprinted sensor surface was characterized by using Field Emission Scanning Electron Microscopy, Electron Impedance Spectroscopy, Cyclic Voltammetry, Square Wave Voltammetry and UV-visible spectroscopy...
May 1, 2017: Talanta
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