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https://www.readbyqxmd.com/read/28454188/metabolic-profiling-of-hoodia-chamomile-terminalia-species-and-evaluation-of-commercial-preparations-using-ultrahigh-performance-liquid-chromatography-quadrupole-time-of-flight-mass-spectrometry
#1
Bharathi Avula, Yan-Hong Wang, Giorgis Isaac, Jimmy Yuk, Mark Wrona, Kate Yu, Ikhlas A Khan
Ultrahigh-performance liquid chromatography quadrupole-time-of-flight mass spectrometry (UHPLC-QToF-MS) profiling was used for the identification of marker compounds and generation of metabolic patterns that could be interrogated using chemometric modeling software. UHPLC-QToF-MS was used to generate comprehensive fingerprints of three botanicals (Hoodia, Terminalia, and chamomile), each having different classes of compounds. Detection of a broad range of ions was carried out in full scan mode in both positive and negative modes over the range m/z 100-1700 using high-resolution mass spectrometry...
April 28, 2017: Planta Medica
https://www.readbyqxmd.com/read/28454058/identification-and-characterization-of-process-related-substances-and-degradation-products-in-apremilast-process-optimization-and-degradation-pathway-elucidation
#2
Yuting Lu, Xiaoyue Shen, Taijun Hang, Min Song
This study aims at investigating the separation, identification and characterization of related substances in apremilast by LC-MS hyphenated techniques, as well as the synthesis optimization and the degradation pathways elucidation. Forced degradation studies were conducted under the ICH prescribed stress conditions. The chromatographic separation was achieved on XBridge C18 column (4.6mm×150mm, 3.5μm) using a mobile phase consisting of water adjusted to pH 3.0 with formic acid as solvent A and acetonitrile as solvent B in linear gradient elution program...
April 2, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28454030/pesticide-impact-study-in-the-peri-urban-horticultural-area-of-gran-la-plata-argentina
#3
Tomás M Mac Loughlin, Leticia Peluso, Damián J G Marino
Vegetable production systems are characterized by intense pesticide use, yet the effects on the surrounding environment are largely unknown and need to be studied. Given this knowledge gap, the objective of this work is to determine the impact of horticulture on a representative watercourse by conducting an integrated study of the occurrence and concentration of pesticides in bottom sediments and their relation to lethal and sublethal effects on benthic fauna. Two sampling campaigns were conducted during seasons of low and high pesticide application in five sites along the Carnaval creek, located in the peri-urban area of La Plata City (Buenos Aires, Argentina)...
April 25, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28454027/levels-and-risk-factors-for-urinary-metabolites-of-polycyclic-aromatic-hydrocarbons-in-children-living-in-chongqing-china
#4
Shudan Liu, Qin Liu, Truls Ostbye, Mary Story, Xu Deng, Yiwen Chen, Wenyan Li, Hong Wang, Jingfu Qiu, Junfeng Zhang
AIMS: Since childhood exposure to polycyclic aromatic hydrocarbons (PAHs) have been associated with a variety of adverse health outcomes, the aims of this study were to1) document PAH exposure levels among children in Chongqing, China by measuring urinary concentrations of four PAH metabolites, 1-hydroxypyrene (1-OHPyr), 2-hydroxynaphthalene (2-OHNap), 2-hydroxyfluorine (2-OHFlu) and 9-hydroxyphenanthrene (9-OHPhe), and 2) assess the associations of urinary concentrations of these PAH metabolites with risk factors related to sources of PAHs inhalation and ingestion exposures and with personal attributes such as sex, age, and BMI...
April 24, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28453688/edlib-a-c-c%C3%A2-library-for-fast-exact-sequence-alignment-using-edit-distance
#5
Martin Šošic, Mile Šikic
Summary: We present Edlib, an open-source C/C ++ library for exact pairwise sequence alignment using edit distance. We compare Edlib to other libraries and show that it is the fastest while not lacking in functionality and can also easily handle very large sequences. Being easy to use, flexible, fast and low on memory usage, we expect it to be easily adopted as a building block for future bioinformatics tools. Availability and Implementation: Source code, installation instructions and test data are freely available for download at https://github...
May 1, 2017: Bioinformatics
https://www.readbyqxmd.com/read/28453660/effect-of-patient-size-anatomical-location-and-modulation-strength-on-dose-delivered-and-image-quality-on-ct-examination
#6
Joël Greffier, Ahmed Larbi, Francesco Macri, Jean-Paul Beregi, Fabricio Pereira
To study the effect of patient size, anatomical location and modulation strength (MS) on image-quality and delivered dose of CT scans acquired with automatic-exposure-control system (AEC). Four anthropomorphic phantoms (three paediatric and one thin adult) were studied, and normal and obese adults were simulated by placing bolus plates around the adult phantom. Thorax and abdomen-pelvis CT were performed using an AEC system equipped with five possible MS. Modulated tube current (mAsmod) was compared to Reference mAs and image-noise was assessed...
April 27, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/28453638/etg-ets-in-serum-by-uhplc-ms-ms-in-suspected-sexual-assault-cases
#7
Solfrid Hegstad, Arne Helland, Cecilie Hagemann, Olav Spigset
A method including semi-automated extraction of ethyl glucuronide (EtG) and ethyl sulfate (EtS) from serum followed by ultra-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS-MS) has been developed and validated. Sample preparation prior to UHPLC-MS-MS analysis consisted of protein precipitation and filtration through a phospholipid removal plate. Chromatography was achieved using an HSS T3 column and gradient elution with formic acid in water in combination with methanol. The mass spectrometer was monitored in the negative mode with multiple reaction monitoring...
April 27, 2017: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28453541/the-real-world-effectiveness-and-safety-of-fingolimod-in-relapsing-remitting-multiple-sclerosis-patients-an-observational-study
#8
Guillermo Izquierdo, Fátima Damas, Maria Dolores Páramo, Juan Luis Ruiz-Peña, Guillermo Navarro
Fingolimod approval was based mainly on two clinical trials, FREEDOMS and TRANSFORMS, which demonstrated the efficacy and safety of fingolimod in patients with multiple sclerosis (MS). We present an observational study that validates these trials findings in a real-world setting, whereby the effectiveness and safety of fingolimod was assessed in Seville's' (Spain) clinical practice. This retrospective study in MS patients assessed effectiveness (relapses, EDSS, gadolinium-enhancing T1 and new/enlarged T2-weighted lesions): total cohort (n = 249) and stratified according to prior treatment (glatiramer acetate/interferon beta-1 [immunomodulator], natalizumab, naïve), gender, basal EDSS score, basal Gd+ lesions, ARR prior to treatment, age at treatment initiation and number of prior treatments...
2017: PloS One
https://www.readbyqxmd.com/read/28453518/lc-ms-ms-quantitative-analysis-reveals-the-association-between-fto-and-dna-methylation
#9
Yuting Zhu, Guangyu Zhou, Xuebin Yu, Qiang Xu, Kai Wang, Dan Xie, Qingkai Yang, Lina Wang
Fat mass and obesity-associated protein (FTO) is α-ketoglutarate-dependent dioxygenase and responsible for demethylating N6-methyladenosine (m6A) in mRNA, 3-methylthymine (m3T) in single-stranded DNA (ssDNA) and 3-methyluracil (m3U) in single-stranded RNA (ssRNA). Its other function remains unknown but thousands of mammalian DNA show 5-methyl-2'-deoxycytidine (5mdC) modification and 5mdC demethylases are required for mammalian energy homeostasis and fertility. Here, we aimed to confirm whether FTO proteins can demethylate 5mdC in DNA...
2017: PloS One
https://www.readbyqxmd.com/read/28453289/identification-of-buctopamine-and-mebuctopamine-a-%C3%AE-2-receptor-agonist-and-its-metabolite-in-swine-hair-and-feed-additives
#10
Ying-Heng Chen, Chia-Ying Yang, Chih Wen Cheng, Yi-Ying Lin, Su Lien Kuo, Ling-Wei Hsin
4-[2-(tert-Butylamino)-1-hydroxyethyl]phenol (buctopamine, 4), a new β2 receptor agonist (β2-agonist), was found to be an adulterant in feed additives for swine in Taiwan, where using β2-agonists in food-production animals is prohibited. Buctopamine and its metabolite, 4-[2-(tert-butylamino)-1-hydroxyethyl]-2-methoxyphenol (mebuctopamine, 2), were detected in swine hair specimens. Authentic compounds 2 and 4 were synthesized with 98.6% and 97.7% purity, respectively, as reference standards for analysis, and both compounds were more hydrophilic than ractopamine and clenbuterol...
April 28, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28453261/comparison-of-metabolomics-approaches-for-evaluating-the-variability-of-complex-botanical-preparations-green-tea-camellia-sinensis-as-a-case-study
#11
Joshua J Kellogg, Tyler N Graf, Mary F Paine, Jeannine S McCune, Olav M Kvalheim, Nicholas H Oberlies, Nadja B Cech
A challenge that must be addressed when conducting studies with complex natural products is how to evaluate their complexity and variability. Traditional methods of quantifying a single or a small range of metabolites may not capture the full chemical complexity of multiple samples. Different metabolomics approaches were evaluated to discern how they facilitated comparison of the chemical composition of commercial green tea [Camellia sinensis (L.) Kuntze] products, with the goal of capturing the variability of commercially used products and selecting representative products for in vitro or clinical evaluation...
April 28, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28453260/origin-of-outstanding-phase-and-moisture-stability-in-na3p1-xasxs4-superionic-conductor
#12
Shun-Li Shang, Zhaoxin Yu, Yi Wang, Donghai Wang, Zi-Kui Liu
Sodium-ion (Na) solid-state electrolytes (SSEs) are critical to address notorious safety issue associated with liquid electrolytes used in the current Na-ion batteries. Fulfilling multiple innovations is a grand challenge but imperative for advanced Na-ion SSE such as a combination of high ionic conductivity and excellent chemical stability. Here, our first-principles and phonon calculations reveal that Na3P1-xAsxS4 (0 ≤ x ≤ 1) is a solid-state superionic conductor stabilized at 0 K by zero-point vibrational energy and at finite temperatures by vibrational and configurational entropies...
April 28, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28453257/one-filter-one-sample-and-the-n-and-o-glyco-proteo-me-towards-a-system-to-study-disorders-of-protein-glycosylation
#13
Kirsty Skeene, Matthew Walker, Graham Clarke, Ed Bergstrom, Paul Genever, Daniel Ungar, Jane Thomas-Oates
A method has been developed for release/isolation of O-glycans from glycoproteins in whole cell lysates, for mass spectrometric analysis. Cells are lysed in SDS, which is then exchanged for urea and ammonium bicarbonate in a centrifugal filter, before treating with NH4OH to release O-glycans. Following centrifugation, O-glycans are recovered in the filtrate. Sonication achieves O-glycan release in 1 h. Combining the established protocol for filter-aided N-glycan separation, here optimised for enhanced PNGase F efficiency, with the developed O-glycan release method allows analysis of both N- and O-glycans from one sample, in the same filter unit, from 0...
April 28, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28453249/complete-mapping-of-complex-disulfide-patterns-with-closely-spaced-cysteines-by-in-source-reduction-and-data-dependent-mass-spectrometry
#14
Christian Necip Cramer, Christian D Kelstrup, Jesper Velgaard Olsen, Kim F Haselmann, Peter Kresten Nielsen
Mapping of disulfide bonds is an essential part of protein characterization to ensure correct cysteine pairings. For this, mass spectrometry (MS) is the most widely used technique due to fast and accurate characterization. However, MS-based disulfide mapping is challenged when multiple disulfide bonds are present in complicated patterns. This includes presence of disulfide bonds in nested patterns and closely-spaced cysteines. Unambiguous mapping of such disulfide bonds typically requires advanced MS approaches...
April 28, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28449397/differential-proteome-profiling-in-the-hippocampus-of-amnesic-mice
#15
Meghraj Singh Baghel, Mahendra Kumar Thakur
Amnesia or memory loss is associated with brain aging and several neurodegenerative pathologies including Alzheimer's disease (AD). This can be induced by a cholinergic antagonist scopolamine, but the underlying molecular mechanism is poorly understood. The present study of proteome profiling in the hippocampus could provide conceptual insights into the molecular mechanisms involved in amnesia. To reveal this, mice were administered scopolamine to induce amnesia and memory impairment was validated by novel object recognition test...
April 27, 2017: Hippocampus
https://www.readbyqxmd.com/read/28449378/analysis-of-toldimfos-in-porcine-muscle-and-bovine-milk-using-liquid-chromatography-triple-quadrupole-mass-spectrometry
#16
Dan Zhang, Jin-A Park, A M Abd El-Aty, Seong-Kwan Kim, Sang-Hyun Cho, Weijia Zheng, Jeong-Min Choi, Jae-Han Shim, Byung-Joon Chang, Jin-Suk Kim, Ho-Chul Shin
An analytical method was developed for the detection of toldimfos sodium residues in porcine muscle and bovine milk using liquid chromatography-triple quadrupole tandem mass spectrometry (LC-MS/MS) analysis. The drug was extracted from muscle and milk using 10 mM ammonium formate in acetonitrile and then purified using n-hexane. The drug was well separated on a Luna C18 column using a mixture of 10 mM ammonium formate in ultrapure water (A) and acetonitrile (B) as the mobile phase. Good linearity was achieved over the tested concentration range (0...
April 27, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28449078/surface-electrocardiography-characteristics-and-radiofrequency-catheter-ablation-of-idiopathic-ventricular-arrhythmias-originating-from-the-left-infero-septal-papillary-muscles-differences-from-those-originating-from-the-left-posterior-fascicle
#17
Shixing Li, Zulu Wang, Zhaoliang Shan, Xiangmin Shi, Ming Liang, Yanchun Liang, Zhiqing Jin, Yaling Han, Yutang Wang
Aims: Distinguishing between ventricular arrhythmias originating from the left ventricular infero-septal papillary muscles (PM) and those from the left posterior fascicle (LPF) by surface electrocardiography (ECG) is very difficult. This study aimed to report the ECG characteristics and radiofrequency catheter ablation of PM and LPF ventricular arrhythmias. Methods and results: A total of 127 patients underwent catheter ablation of idiopathic ventricular arrhythmias originating from the LPF (n = 106; 85 males; 10-70 years) or PM (n = 21; 14 males; 4-68 years) were studied...
April 24, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28448889/studies-on-the-metabolites-difference-of-psoralen-isopsoralen-in-human-and-six-mammalian-liver-microsomes-in-vitro-by-uhplc-ms-ms
#18
Aihong Yang, Junxiu Chen, Yetao Ma, Lili Wang, Yaowen Fan, Xin He
Psoralen and isopsoralen are found in many fruits, vegetables and traditional Chinese medicines (TCM), such as Ficus carica L., Celery, Fructus Psoraleae etc. Modern pharmacological studies found that psoralen and isopsoralen can show estrogen-like activity, antitumor, and antibacterial activities etc. However, some research results also show some liver damage associated with the use of psoralen/isopsoralen or related medicines in human. Many studies focus on the pharmacological activities of psoralen/isopsoralen, while it is important to choose the suitable pharmacological models which are relevant to human in drug metabolism and pharmacokinetic process...
April 20, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28448888/isolation-identification-and-characterization-of-potential-impurities-of-anidulafungin
#19
Lanning Zhao, Qilong Wang, Yi Bie, Xiaoxia Lu
Eight impurities ranging from 0.03 to 0.97% in anidulafungin bulk drug were detected by HPLC. Four impurities (Imp-I, Imp-II, Imp-III and Imp-VIII) among impurities were isolated from the self-prepared or marketed samples of anidulafungin bulk drug by means of preparative HPLC. A thorough study was undertaken to characterize these impurities and based on 1D ((1)H, (13)C, H-D, DEPT 90 and 135) and 2D (COSY, TOCSY, HSQC, HMBC) NMR and ESI-MS spectral data. Based on the characterization data, Imp-I was found to be known open-chain hydrolysis product formed during the synthesis and degradation...
April 17, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28448886/new-analytical-method-for-determination-of-epimer-metabolites-in-rat-plasma-after-oral-administration-of-paeoniflorin-by-uplc-tof-ms-following-picolinoyl-derivatization
#20
Zhigang Wang, Shuhan Tang, Masao Hattori, Hailong Zhang, Ping Wang, Xiuhong Wu, Ning Zhang
A highly sensitive analytical method was developed to study the in vivo metabolism of paeoniflorin, one of the most principal components in traditional Chinese medicine. After hydrolyzation with sulfatase, the epimer metabolites 7S-paeonimetabolin I and 7R-paeonimetabolin I of paeoniflorin in rat plasma were successfully detected and well separated by LC-MS following picolinoyl derivatization for the first time. Borneol was used as the internal standard to quantify 7S-paeonimetabolin I and 7R-paeonimetabolin I in rat plasma...
April 19, 2017: Journal of Pharmaceutical and Biomedical Analysis
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