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https://www.readbyqxmd.com/read/28343244/a-new-reactive-1-8-naphthalimide-derivative-for-highly-selective-and-sensitive-detection-of-hg-2
#1
Feng Lv, Yufen Chen, Tengxuan Tang, Yuhua Chen, Dongmei Xu
A 1,8-naphthalimide derivative with a reactive aliphatic hydroxyl was designed and synthesized as a fluorescent probe. Its structure was characterized by IR, (1)H NMR, (13)C NMR, LC-MS and HPLC. The probe showed high selectivity and sensitivity to Hg(2+) over other metal ions such as Pb(2+), Na(+), K(+), Cd(2+), Cr(3+), Zn(2+), Cu(2+), Ni(2+), Ca(2+), Fe(3+), Fe(2+), Co(2+), Mn(2+) and Mg(2+) in MeCN/H2O (15/85, v/v). The increase in fluorescence intensity was linearly proportional to the concentration of Hg(2+) in the range of 18-40 μM with a detection limit of 1...
March 25, 2017: Journal of Fluorescence
https://www.readbyqxmd.com/read/28343106/a-structure-based-plasma-protein-pre-fractionation-using-conjoint-immobilized-metal-chelate-affinity-ima-system
#2
Karan Karkra, Kishore K R Tetala, M A Vijayalakshmi
The potential of immobilized metal/chelate affinity (IMA) in a continuous fashion, referred as conjoint approach, to pre-fractionate plasma proteins (in their native state) prior to LC-MS analysis was investigated in this study. Four transition metal-ions (Co (II), Zn (II), Ni (II) and Cu (II)) were individually chelated with IDA (iminodiacetic acid) coated CIM (Convective Interaction Media) disks and placed in a single housing in the following sequential order: IDA-Co (II)→IDA-Zn (II)→IDA-Ni (II)→IDA-Cu (II)...
March 10, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28343078/development-and-validation-of-liquid-chromatography-tandem-mass-spectrometry-method-quantitative-determination-of-polymyxin-b1-polymyxin-b2-polymyxin-b3-and-isoleucine-polymyxin-b1-in-human-plasma-and-its-application-in-clinical-studies
#3
Kim H Hee, Yee K J Leaw, Jun L Ong, Lawrence S Lee
Polymyxin B (PB) is an antibiotic consisting of a cyclic heptapeptide and a tripeptide side chain used in treatment of infections caused by Gram-negative bacteria. Commercial formulations of PB contain multiple structurally related components with major constituents of PB1, PB2, PB3 and ile-PB1. To understand the pharmacokinetics of these major components, we have developed and validated a LC-MS/MS method to quantify PB1, PB2, PB3 and ile-PB1 in human plasma. PB was extracted from plasma by protein precipitation using trichloroacetic acid followed by chromatographic separation on Zorbax Bonus-RP column (100mm×2...
March 14, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28343077/separation-and-characterization-of-unknown-impurities-and-isomers-in-flomoxef-sodium-by-lc-it-tof-ms-and-study-of-their-negative-ion-fragmentation-regularities
#4
Xu Yu, Fan Wang, Jiani Li, Weiguang Shan, Bingqi Zhu, Jian Wang
Thirteen unknown impurities in flomoxef sodium were separated and characterized by liquid chromatography coupled with high resolution ion trap/time-of-flight mass spectrometry (LC-IT-TOF MS)with positive and negative modes of electrospray ionization method for further improvement of official monographs in pharmacopoeias. The fragmentation patterns of impurities in flomoxef in the negative ion mode were studied in detail, and new negative-ion fragmentation regularities were discovered. Chromatographic separation was performed on a Kromasil C18 column (250mm×4...
March 19, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28342858/aqueous-extract-from-leaf-of-artocarpus-altilis-provides-cardio-protection-from-isoproterenol-induced-myocardial-damage-in-rats-negative-chronotropic-and-inotropic-effects
#5
Chukwuemeka Nwokocha, Javier Palacios, Mario J Simirgiotis, Jemesha Thomas, Magdalene Nwokocha, Lauriann Young, Rory Thompson, Fredi Cifuentes, Adrian Paredes, Rupika Delgoda
ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Artocarpus altilis (Parkinson ex F.A.Zorn, Fosberg) (Moraceae) are used in the management of hypertension; this study assessed the cardio-protective effects of the leaf extract on isoproterenol (ISO) induced myocardial damage in rats. MATERIAL AND METHODS: Twenty (20) adult male Sprague-Dawley rats (175-230g) were divided into 5 groups. Group 1 (Control), 2 (AA) received 50mg/Kg Artocarpus altilis (AA) only; 3 (ISO) received 85mg/Kg ISO only; 4 (ISO+AA/50) and 5 (ISO+AA/100) received 50 and 100mg/Kg AA respectively for 6 days, after induced with ISO twice (85mg/Kg) at a 24-hour period...
March 22, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/28342347/assumed-non-persistent-environmental-chemicals-in-human-adipose-tissue-matrix-stability-and-correlation-with-levels-measured-in-urine-and-serum
#6
F Artacho-Cordón, J P Arrebola, O Nielsen, P Hernández, N E Skakkebaek, M F Fernández, A M Andersson, N Olea, H Frederiksen
The aim of this study was to (1) optimize a method for the measurement of parabens and phenols in adipose tissue, (2) evaluate the stability of chemical residues in adipose tissue samples, and (3) study correlations of these compounds in urine, serum, and adipose tissue. Samples were obtained from adults undergoing trauma surgery. Nine phenols and seven parabens were determined by isotope diluted TurboFlow-LC-MS/MS. The analytical method showed good accuracy and precision. Limits of detection (LOD) for parabens and phenols ranged from 0...
March 22, 2017: Environmental Research
https://www.readbyqxmd.com/read/28340472/characterization-of-an-unknown-impurity-in-doxofylline-using-lc-ms-and-nmr
#7
Peixi Zhu, Jingxian Lu, Liya Hong, Weike Su, Ann Van Schepdael, Erwin Adams
During quality control of doxofylline, a novel impurity was detected, which was above the identification threshold defined by ICH. First, a liquid chromatographic method compatible with mass spectrometric (MS) detection was developed. Based on tandem multistage MS and high resolution MS data, the unknown impurity was found to consist of two theophylline groups connected by a methylene group. The structure was further confirmed by 1D and 2D nuclear magnetic resonance (NMR) experiments after semi-preparative isolation...
March 18, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28340471/chemotaxonomic-studies-of-nine-paris-species-from-china-based-on-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry-and-fourier-transform-infrared-spectroscopy
#8
Yuanzhong Wang, Ehu Liu, Ping Li
Paris species, which contain steroid saponins, have been used as herb folk medicines in Asia. In the present study, a comprehensive strategy based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and Fourier transform infrared (FT-IR) spectroscopy was firstly proposed to evaluate the chemotaxonomic relationships of nine Paris species sampled from different geographical regions in China. Principle component analysis (PCA) based on FT-IR data revealed chemical similarities in term of the nine species and geographical regions, indicating the accumulation of metabolites affected by the combination of geographical factors and species...
March 18, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28340369/degradation-of-diclofenac-by-uv-activated-persulfate-process-kinetic-studies-degradation-pathways-and-toxicity-assessments
#9
Xian Lu, Yisheng Shao, Naiyun Gao, Juxiang Chen, Yansen Zhang, Huiming Xiang, Youluo Guo
Diclofenac (DCF) is the frequently detected non-steroidal pharmaceuticals in the aquatic environment. In this study, the degradation of DCF was evaluated by UV-254nm activated persulfate (UV/PS). The degradation of DCF followed the pseudo first-order kinetics pattern. The degradation rate constant (kobs) was accelerated by UV/PS compared to UV alone and PS alone. Increasing the initial PS dosage or solution pH significantly enhanced the degradation efficiency. Presence of various natural water constituents had different effects on DCF degradation, with an enhancement or inhibition in the presence of inorganic anions (HCO3(-) or Cl(-)) and a significant inhibition in the presence of NOM...
March 21, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28340368/synthesis-molecular-docking-antimycobacterial-and-antimicrobial-evaluation-of-new-pyrrolo-3-2-c-pyridine-mannich-bases
#10
Gilish Jose, Tholappanavara H Suresha Kumara, Haliwana B V Sowmya, Dharmarajan Sriram, Tayur N Guru Row, Amar A Hosamani, Sunil S More, Bhavya Janardhan, B G Harish, Sandeep Telkar, Yalegara Siddappa Ravikumar
In this report, we describe the synthesis and biological evaluation of a new series of pyrrolo[3,2-c]pyridine Mannich bases (7a-v). The Mannich bases were obtained in good yields by one-pot three component condensation of pyrrolo[3,2-c]pyridine scaffold (6a-c) with secondary amines and excess of formaldehyde solution in AcOH. The chemical structures of the compounds were characterized by (1)H NMR, (13)C NMR, LC/MS and elemental analysis. Single crystal X-ray diffraction has been recorded for compound 7k ([C23H29ClN4](+2), H2O)...
March 16, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28340309/analytical-techniques-in-lipidomics-state-of-the-art
#11
Kamil Jurowski, Kamila Kochan, Justyna Walczak, Małgorzata Barańska, Wojciech Piekoszewski, Bogusław Buszewski
Current studies related to lipid identification and determination, or lipidomics in biological samples, are one of the most important issues in modern bioanalytical chemistry. There are many articles dedicated to specific analytical strategies used in lipidomics in various kinds of biological samples. However, in such literature, there is lack of articles dedicated to a comprehensive review of the actual analytical methodologies used in lipidomics. The aim of this article is to characterize the lipidomics methods used in modern bioanalysis according to the methodological point of view: 1) chromatography/separation methods, 2) spectroscopic methods and 3) mass spectrometry and also hyphenated methods...
March 24, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28339059/proteomic-based-identification-of-hsp70-as-a-tumor-associated-antigen-in-ovarian-cancer
#12
Xin-Xin Liu, Hua Ye, Peng Wang, Liu-Xia Li, Yi Zhang, Jian-Ying Zhang
Ovarian cancer commonly presents without prominent symptoms and is consequently diagnosed at advanced stages with unfavorable prognosis. Novel serological biomarkers for the early detection and clinical management of ovarian cancer are imminently needed. Proteomic-based methods for biomarker discovery are promising strategies implemented in cancer research. The aim of the present study was to identify new tumor antigens from the ovarian cancer cell line SKOV3 and their associated autoantibodies in sera of patients with ovarian cancer employing proteomic-based approaches...
March 24, 2017: Oncology Reports
https://www.readbyqxmd.com/read/28338045/abnormal-levels-of-histone-methylation-in-the-retinas-of-diabetic-rats-are-reversed-by-minocycline-treatment
#13
Wenjun Wang, Simone Sidoli, Wenquan Zhang, Qing Wang, Leilei Wang, Ole N Jensen, Lin Guo, Xiaolu Zhao, Ling Zheng
In this study we quantified the alterations of retinal histone post-translational modifications (PTMs) in diabetic rats using a liquid chromatography - tandem mass spectrometry (LC-MS/MS) approach. Some diabetic rats were subsequently treated with minocycline, a tetracycline antibiotic, which has been shown to inhibit the diabetes-induced chronic inflammation in the retinas of rodents. We quantified 266 differentially modified histone peptides, including 48 out of 83 methylation marks with significantly different abundancein retinas of diabetic rats as compared to non-diabetic controls...
March 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28336725/quantitative-shotgun-proteomics-unveils-candidate-novel-oesophageal-adenocarcinoma-specific-proteins
#14
J Robert O'Neill, Hui-Song Pak, Erola Pairo-Castineira, Vicki Save, Simon Paterson-Brown, Rudolf Nenutil, Bořivoj Vojtěšek, Ian Overton, Alex Scherl, Ted R Hupp
Oesophageal cancer is the eighth most common cancer worldwide and the majority of patients have systemic disease at presentation. Oesophageal adenocarcinoma (OAC), the predominant subtype in western countries, is largely resistant to current chemotherapy regimens. Selective markers are needed to enhance clinical staging and to allow targeted therapies yet there are minimal proteomic data on this cancer type. After histological review, lysates from OAC and matched normal oesophageal and gastric samples from seven patients were subjected to LC MS/MS after tandem mass tag labelling and OFFGEL fractionation...
March 23, 2017: Molecular & Cellular Proteomics: MCP
https://www.readbyqxmd.com/read/28335977/simultaneous-determination-of-ethanol-s-four-types-of-non-oxidative-metabolites-in-human-whole-blood-by-liquid-chromatography-tandem-mass-spectrometry
#15
Xinyu Zhang, Feng Zheng, Zebin Lin, Sys Stybe Johansen, Tianfang Yu, Yuming Liu, Zhibin Huang, Jiaolun Li, Jie Yan, Yulan Rao
The importance of ethanol non-oxidative metabolites as the specific biomarkers of alcohol consumption in clinical and forensic settings is increasingly acknowledged. Simultaneous determination of these metabolites can provide a wealth of information like drinking habit and history, but it was difficult to achieve because of their wide range of polarity. This work describes development and validation of a simple liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for 4 types of ethanol non-oxidative metabolites (ethyl glucuronide, ethyl sulfate, fatty acid ethyl esters and phosphatidylethanols) in 50 μL of human whole blood...
April 22, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28335970/quinine-bonded-to-superficially-porous-particles-for-high-efficiency-and-ultrafast-liquid-and-supercritical-fluid-chromatography
#16
Darshan C Patel, Zachary S Breitbach, JeongJae Yu, Kate A Nguyen, Daniel W Armstrong
Two new anion-exchange columns were prepared by bonding tert-butyl carbamoylated quinine to 2.7 μm superficially porous particle (SPP) silica to create chiral stationary phases for high-efficiency and ultrafast chromatography. Performance and retention parameters of these new columns are compared with an analogous 5 μm fully porous particle (FPP) based Chiralpak QNAX column and a 3-4 fold increase in efficiency was observed. Ultrafast separations ranging from 12 s down to sub-second are shown using 2.7 μm SPPs bonded via hydrosilation to the selector...
April 22, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28335604/prioritizing-natural-product-diversity-in-a-collection-of-146-bacterial-strains-based-on-growth-and-extraction-protocols
#17
Max Crüsemann, Ellis C O'Neill, Charles B Larson, Alexey V Melnik, Dimitrios J Floros, Ricardo R da Silva, Paul R Jensen, Pieter C Dorrestein, Bradley S Moore
In order to expedite the rapid and efficient discovery and isolation of novel specialized metabolites, while minimizing the waste of resources on rediscovery of known compounds, it is crucial to develop efficient approaches for strain prioritization, rapid dereplication, and the assessment of favored cultivation and extraction conditions. Herein we interrogated bacterial strains by systematically evaluating cultivation and extraction parameters with LC-MS/MS analysis and subsequent dereplication through the Global Natural Product Social Molecular Networking (GNPS) platform...
March 24, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28335578/exploring-the-antitumor-mechanism-of-high-dose-cytarabine-through-the-metabolic-perturbations-of-ribonucleotide-and-deoxyribonucleotide-in-human-promyelocytic-leukemia-hl-60-cells
#18
Zheng Li, Jian-Ru Guo, Qian-Qian Chen, Cai-Yun Wang, Wei-Jia Zhang, Mei-Cun Yao, Wei Zhang
Despite the apparent clinical benefits of high-dose cytarabine (Ara-C) over lower dose Ara-C in acute myeloid leukemia (AML) therapy, the mechanism behind high-dose Ara-C therapy remains uncertain. In this study, a LC-MS-based method was carried out to investigate the metabolic alteration of ribonucleotide and deoxyribonucleotide in human promyelocytic leukemia cells (HL-60) after treatment with Ara-C to reveal its antitumor mechanism. The metabolic results revealed that four nucleotides (ATP, ADP, CDP, and dCTP) could be used as potential biomarkers indicating the benefit of high-dose Ara-C over lower dose Ara-C treatment...
March 21, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28335036/validated-method-for-the-screening-and-quantification-of-baclofen-gabapentin-and-pregabalin-in-human-post-mortem-whole-blood-using-protein-precipitation-and-liquid-chromatography-tandem-mass-spectrometry
#19
Limon Nahar, Amy Smith, Rajan Patel, Rebecca Andrews, Sue Paterson
There has been a rapid increase in the number of prescriptions for baclofen (BLF), gabapentin (GBP) and pregabalin (PGL) in the UK since their introduction to therapy. Recent studies across the European Union and USA have shown the illicit abuse potential of these drugs and deaths have been observed. A simple, reliable and fully validated method was developed for the screening and quantification of BLF, GBP and PGL in human post-mortem (PM) blood. The analytes and their deuterated analogs as internal standard were extracted from blood using a single addition acetonitrile protein precipitation reaction followed by analysis using liquid chromatography-tandem mass spectrometry (LC-MS-MS) with triggered dynamic multiple reaction monitoring mode for simultaneous confirmation and quantification...
March 10, 2017: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28335025/a-novel-lc-ms-ms-method-with-an-effective-antioxidant-for-the-determination-of-edaravone-a-free-radical-scavenger-in-dog-plasma-and-its-application-to-a-pharmacokinetic-study
#20
Feng Shao, Xiao-Ling Hu, Xin Liu, Mang-Ting Shan
The objective of this study was to investigate the stability of edaravone in dog plasma by using an added antioxidant stabilizer, with an ultimate goal of developing and validating a sensitive, reliable and robust LC-MS-MS method for determination of edaravone in plasma samples. Edaravone was unstable in plasma, but it presented a good stability performance in the plasma with sodium metabisulfite (SMB), an effective antioxidant. The blood sample was collected in the heparinized eppendorf tube containing SMB and plasma sample was deproteinized using acetonitrile containing 20 ng/mL of phenacetin (Internal standard)...
March 2, 2017: Journal of Chromatographic Science
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