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https://www.readbyqxmd.com/read/29030154/simultaneous-profiles-of-sulfonated-androgens-sulfonated-estrogens-and-sulfonated-progestogens-in-postpubertal-boars-sus-scrofa-domestica-measured-by-lc-ms-ms
#1
G Schuler, A Sánchez-Guijo, M F Hartmann, S A Wudy
Sulfonated steroids (s-St) have been usually regarded as inactive metabolites but are progressively considered as precursors for the intra-tissue formation of bioactive steroids. Moreover, independent effects without preceding removal of the sulfate group have been observed. We use the porcine testicular-epididymal compartment as a model to investigate the still largely unknown s-St physiology as the boar exhibits an intriguingly broad s-St spectrum predominantly originating from the testis. The application of LC-MS/MS in steroidomics enables the determination of unconjugated and intact sulfonated steroids with currently highest specificity and good sensitivity, allowing the concurrent measuring of numerous analytes in larger quantities of samples...
October 10, 2017: Journal of Steroid Biochemistry and Molecular Biology
https://www.readbyqxmd.com/read/29029194/envelope-proteome-changes-driven-by-rama-overproduction-in-klebsiella-pneumoniae-that-enhance-acquired-%C3%AE-lactam-resistance
#2
Juan-Carlos Jiménez-Castellanos, Wan Ahmad Kamil Wan Nur Ismah, Yuiko Takebayashi, Jacqueline Findlay, Thamarai Schneiders, Kate J Heesom, Matthew B Avison
Objectives: In Klebsiella pneumoniae, overproduction of RamA results in reduced envelope permeability and reduced antimicrobial susceptibility but clinically relevant resistance is rarely observed. Here we have tested whether RamA overproduction can enhance acquired β-lactam resistance mechanisms in K. pneumoniae and have defined the envelope protein abundance changes upon RamA overproduction during growth in low and high osmolarity media. Methods: Envelope permeability was estimated using a fluorescent dye accumulation assay...
October 6, 2017: Journal of Antimicrobial Chemotherapy
https://www.readbyqxmd.com/read/29029070/development-and-validation-of-an-lc-tandem-ms-assay-for-the-quantification-of-%C3%AE-lactam-antibiotics-in-the-sputum-of-cystic-fibrosis-patients
#3
Katrien Forier, Virginie Van Heck, Mieke Carlier, Eva Van Braeckel, Sabine Van Daele, Frans De Baets, Petra Schelstraete, Filomeen Haerynck, Veronique Stove, Leen Van Simaey, Mario Vaneechoutte, Alain G Verstraete
Objectives: Antibiotic therapy is of vital importance for the control of infectious exacerbations in cystic fibrosis (CF) patients. However, very little is known regarding the fraction of systemically administered antibiotics reaching the lower respiratory tract secretions. We developed and validated a method to measure the concentrations of piperacillin, ceftazidime, meropenem and aztreonam in CF sputum, and present the validation data. Methods: Ultra-performance LC coupled to tandem MS was used...
September 27, 2017: Journal of Antimicrobial Chemotherapy
https://www.readbyqxmd.com/read/29028822/serial-omics-characterization-of-equine-urine
#4
Min Yuan, Susanne B Breitkopf, John M Asara
Horse urine is easily collected and contains molecules readily measurable using mass spectrometry that can be used as biomarkers representative of health, disease or drug tampering. This study aimed at analyzing microliter levels of horse urine to purify, identify and quantify proteins, polar metabolites and non-polar lipids. Urine from a healthy 12 year old quarter horse mare on a diet of grass hay and vitamin/mineral supplements with limited pasture access was collected for serial-omics characterization. The urine was treated with methyl tert-butyl ether (MTBE) and methanol to partition into three distinct layers for protein, non-polar lipid and polar metabolite content from a single liquid-liquid extraction and was repeated two times...
2017: PloS One
https://www.readbyqxmd.com/read/29028670/cord-blood-bisphenol-a-levels-and-reproductive-and-thyroid-hormone-levels-of-neonates-the-hokkaido-study-on-environment-and-children-s-health
#5
Machiko Minatoya, Seiko Sasaki, Atsuko Araki, Chihiro Miyashita, Sachiko Itoh, Jun Yamamoto, Toru Matsumura, Takahiko Mitsui, Kimihiko Moriya, Kazutoshi Cho, Keita Morioka, Hisanori Minakami, Nobuo Shinohara, Reiko Kishi
BACKGROUND: Bisphenol A (BPA) is widely used and BPA exposure is nearly ubiquitous in developed countries. While animal studies have indicated adverse health effects of prenatal BPA exposure including reproductive dysfunction and thyroid function disruption possibly in a sex-specific manner, findings from epidemiologic studies have not been enough to prove these adverse effects. Given very limited research on human, the aim of this study was to investigate associations between cord blood BPA levels and reproductive and thyroid hormone levels of neonates and whether associations differed by neonate sex...
October 2017: Epidemiology
https://www.readbyqxmd.com/read/29028617/a-plasma-lipidomics-strategy-reveals-perturbed-lipid-metabolic-pathways-and-potential-lipid-biomarkers-of-human-colorectal-cancer
#6
Sensen Shen, Li Yang, Linnan Li, Yu Bai, Chun Cai, Huwei Liu
To explore underlying molecular mechanisms and identify novel lipid biomarkers promising for colorectal cancer (CRC) diagnosis, a continuous-flow two dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry (2D LC-QToF/MS) method was employed to comprehensively measure lipid species in human plasma of CRC patients and healthy controls. With a total of 427 annotated lipid species, we identified 64 lipid species with corrected p value less than 0.05 and fold change more than 1.5. These significantly altered lipid species were mainly involved in glycerolipids and glycerophospholipids metabolism and sphingolipids metabolism...
October 4, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29028405/evaluation-of-plasma-peptides-extraction-methods-by-high-resolution-mass-spectrometry
#7
N V Zakharova, A Y Shornikova, A E Bugrova, V V Baybakova, M I Indeykina, A S Kononikhin, I A Popov, O I Kechko, A A Makarov, E N Nikolaev
Monitoring of peptides offers a promising approach for the discovery of novel biomarkers, which might be valuable for detection, treatment and prevention of large variety of diseases. Development of highly effective methods for plasma peptide extraction remains an important task. In the current study, we applied different types of plasma peptide extraction approaches to reveal efficient methods which would provide the highest peptide yield. We used different combinations of plasma treatment with acetonitrile and/or urea/guanidine, protein precipitation by acetone, gel-filtration, ultrafiltration, and two types of solid phase extraction...
August 2017: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/29028400/label-free-study-of-cosmonaut-s-urinary-proteome-changes-after-long-duration-spaceflights
#8
A Brzhozovskiy, A Kononikhin, M Indeykina, LKh Pastushkova, I A Popov, E N Nikolaev, I M Larina
During the entire time that cosmonauts stay on board the international space station, different extreme space flight factors affect their bodies. In order to find out what physiological changes occur under the influence of spaceflight, different parameters of the human body before and after flights are monitored. Analysis of the urine proteome is one of the most perspective non-invasive methods of condition monitoring. The aim of the study was to perform a comparative semi-quantitative label-free urine proteome analysis of samples collected from 21 cosmonauts before and after long-duration spaceflight at the international space station...
August 2017: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/29028381/dependence-of-matrix-effect-on-ionization-polarity-during-lc-esi-ms-analysis-of-derivatized-amino-acids-in-some-natural-samples
#9
Maarja-Liisa Oldekop, Riin Rebane, Koit Herodes
Matrix effect, the influence of co-eluting components on the ionization efficiency of the analyte, affects the trueness and precision of the LC-ESI-MS analysis. Derivatization can reduce or eliminate matrix effect, for example, diethyl ethoxymethylenemalonate (DEEMM) derivatives have shown less matrix effect compared to other derivatives. Moreover, the use of negative ion mode can further reduce matrix effect. In order to investigate the combination of derivatization and different ionization modes, an LC-ESI-MS/MS method using alternating positive/negative ion mode was developed and validated...
October 2017: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/29028333/profiling-and-quantification-of-regioisomeric-caffeoyl-glucoses-in-berry-fruits
#10
Maria Alexandra Patras, Nikolai Kuhnert, Rakesh Jaiswal, Gordon J McDougall
Based on a recently developed tandem MS based hierarchical scheme for the identification of regioisomeric caffeoyl glucoses, selected berry fruits were profiled for their caffeoyl glucose ester content. Fresh edible berries profiled included strawberries, raspberries, blueberries, blackberries, red and black currants, lingonberries, gooseberries, cranberries, juice of elderberries, goji berries, chokeberries, cranberries, açai berries, sea buckthorn berries, Montmorency sour cherries, and pomegranate were investigated...
October 13, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29028307/metabolomics-of-small-numbers-of-cells-metabolomic-profiling-of-100-1000-and-10000-human-breast-cancer-cells
#11
Xian Luo, Liang Li
In cellular metabolomics, it is desirable to carry out metabolomic profiling using a small number of cells in order to save time and cost. In some applications (e.g., working with circulating tumor cells in blood), only a limited number of cells are available for analysis. In this report, we describe a method based on high-performance chemical isotope labeling (CIL) nanoflow liquid chromatography mass spectrometry (nanoLC-MS) for high-coverage metabolomic analysis of small numbers of cells (i.e., ≤10000 cells)...
October 13, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29027968/rapid-identification-of-dipeptidyl-peptidase-iv-dpp-iv-inhibitory-peptides-from-ruditapes-philippinarum-hydrolysate
#12
Rui Liu, Lei Zhou, Yan Zhang, Nai-Juan Sheng, Zhi-Kang Wang, Ti-Zhi Wu, Xin-Zhi Wang, Hao Wu
Dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides were rapidly identified from Ruditapes philippinarum hydrolysate. The hydrolysate was fractionated by ethanol precipitation and preparative reverse phase high-performance liquid chromatography (RP-HPLC). The fraction which showed the highest DPP-IV inhibitory activity was then analyzed by a high-throughput nano-liquid chromatography electrospray ionization tandem mass spectrometry (nano-LC ESI-MS/MS) method, and the sequences of peptides were identified based on the MS/MS spectra against the Mollusca protein data from the UniProt database...
October 13, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29027487/effect-of-tauroursodeoxycholic-acid-on-pufa-levels-and-inflammation-in-an-animal-and-cell-model-of-hepatic-endoplasmic-reticulum-stress
#13
M Aslan, E Kıraç, Ö Yılmaz, B Ünal, E K Konuk, F Özcan, H Tuzcu
The aim of this study was to evaluate hepatic polyunsaturated fatty acids (PUFAs) and inflammatory response in an animal and cell model of endoplasmic reticulum (ER) stress. Rats were divided into control, tunicamycin (TM)-treated, and TM + tauroursodeoxycholic acid (TUDCA)-treated groups. Hepatic ER stress was induced by TM and the ER stress inhibitor TUDCA was injected 30 min before induction of ER stress. Liver THLE-3 cells were treated with TM and TUDCA was administered in advance to decrease cytotoxic effects...
January 1, 2017: Human & Experimental Toxicology
https://www.readbyqxmd.com/read/29027453/-ubiquitinated-proteomics-research-of-hep3b
#14
Yingzi Qi, Chen Deng, Na Su, Lingqiang Zhang, Ping Xu
Ubiquitination is one of the most major post-translational modifications playing important role in regulation of intra-cellular proteins' stability, degradation, localization and biological activity. However, these proteins are difficult to be detected due to their low abundance, short half-life. In this study, ubiquitin-binding domains (UBDs) were constructed to purify the ubiquitinated proteins from Hep3B cells. Ubiquitinated proteins and sites were detected by LC-MS/MS. A total of 1 900 potential ubiquitinated proteins were identified...
October 25, 2016: Sheng Wu Gong Cheng Xue Bao, Chinese Journal of Biotechnology
https://www.readbyqxmd.com/read/29027369/range-of-therapeutic-prothipendyl-and-prothipendyl-sulfoxide-concentrations-in-clinical-blood-samples
#15
Michael Krämer, Peter Heese, Markus Banger, Burkhard Madea, Cornelius Hess
Due to a lack of reference blood concentrations in the literature, the forensic evaluation of prothipendyl findings in blood samples is difficult. Interpretations with regard to the assessment of blood concentrations as well as an estimation of the ingested prothipendyl amounts were often vague. To describe a concentration range in clinical samples, prothipendyl and prothipendyl sulfoxide concentrations were determined in serum samples of 50 psychiatric patients receiving 40 mg, 80 mg or 160 mg doses of prothipendyl...
October 12, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/29027249/development-of-an-lc-ms-ms-method-for-quantification-of-two-isomeric-phenylpropenes-and-the-application-to-pharmacokinetic-studies-in-rats
#16
Qiong Yang, Zhipeng Deng, Fang Zhang, Peilu Sun, Jun Li, Wanjin Zheng
Isomers β-asarone and α-asarone have recently demonstrated differential pharmacological activities. Here, we report an LC-MS/MS method developed using acetonitrile to extract two isomeric phenylpropenes from rat plasma. Separation was achieved using a XDB-C18 column (100 × 2.1 mm; i.d., 1.8 μm) with a mobile phase of methanol:0.1% formic acid (55:45, v/v) at a flow rate of 0.3 mL/min. Calibration curves ranging from 5.20 to 2080 ng/mL for β-asarone and from 3.68 to 1470 ng/mL for α-asarone were linear (r(2) ≥0...
October 12, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29027209/heterogeneous-distribution-of-alectinib-in-neuroblastoma-xenografts-revealed-by-matrix-assisted-laser-desorption-ionisation-mass-spectrometry-imaging-a-pilot-study
#17
Shoraku Ryu, Mitsuhiro Hayashi, Hiroaki Aikawa, Isamu Okamoto, Yasuhiro Fujiwara, Akinobu Hamada
BACKGROUND AND PURPOSE: The penetration of the anaplastic lymphoma kinase (ALK) inhibitor alectinib in neuroblastomas and the relationship between alectinib and ALK expression are unknown. The aim of this study was to perform a quantitative investigation of the inter- and intra-tumoural distribution of alectinib in different neuroblastoma xenograft models using matrix-assisted laser desorption ionisation mass spectrometry imaging (MALDI-MSI). EXPERIMENTAL APPROACH: The distribution of alectinib in NB1 (ALK amplification) and SK-N-FI (ALK wild-type) xenograft tissues was analysed using MALDI-MSI...
October 13, 2017: British Journal of Pharmacology
https://www.readbyqxmd.com/read/29026979/hpaec-pad-for-oligosaccharide-analysis-novel-insights-into-analyte-sensitivity-and-response-stability
#18
Matthias Mechelke, Jonathan Herlet, J Philipp Benz, Wolfgang H Schwarz, Vladimir V Zverlov, Wolfgang Liebl, Petra Kornberger
The rising importance of accurately detecting oligosaccharides in biomass hydrolyzates or as ingredients in food, such as in beverages and infant milk products, demands for the availability of tools to sensitively analyze the broad range of available oligosaccharides. Over the last decades, HPAEC-PAD has been developed into one of the major technologies for this task and represents a popular alternative to state-of-the-art LC-MS oligosaccharide analysis. This work presents the first comprehensive study which gives an overview of the separation of 38 analytes as well as enzymatic hydrolyzates of six different polysaccharides focusing on oligosaccharides...
October 12, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29026259/identification-of-a-tbhq-interfering-peak-in-crude-canola-oil-using-aocs-official-method-ce-6-86-and-its-chromatographic-resolution
#19
Michael R Blumhorst, Travis Mahan, Kathryn Stanley, Aaron Griffith, Mark W Collison
AOCS Official Method Ce 6-86 "Antioxidants, Liquid Chromatographic Method" was originally developed to confirm the correct antioxidant was added at the specified concentration to refined oils. Today, this method is increasingly utilized to validate that antioxidants are absent from oil products. False positive results can have a significant impact on the ability to sell products in specific markets and can impart additional business expenditures for conclusive secondary analyses. In the current work, quantification of tert-butylhydroquinone (TBHQ) in crude canola/rapeseed oil using liquid chromatography (LC) with ultraviolet (UV) detection was compromised by an interfering peak...
2017: Journal of the American Oil Chemists' Society
https://www.readbyqxmd.com/read/29024911/simultaneous-quantitative-analysis-of-uremic-toxins-by-lc-ms-ms-with-a-reversed-phase-cation-exchange-anion-exchange-tri-modal-mixed-mode-column
#20
Yoshitomi Kanemitsu, Kei Asaji, Yotaro Matsumoto, Hiroki Tsukamoto, Daisuke Saigusa, Chikahisa Mukawa, Tatsuki Tachikawa, Takaaki Abe, Yoshihisa Tomioka
Column choice is crucial to the development of liquid chromatography/tandem mass spectrometry (LC-MS/MS) methods because analyte selectivity is dependent on the nature of the stationary phase. Recently, mixed-mode chromatography, which employs a combination of two or more stationary phases and solvent systems, has emerged as an alternative to multiple, complementary, single-column systems. This report describes the development and validation of a novel analytical method based on LC-MS/MS employing a reversed-phase/cation-exchange/anion-exchange tri-modal column (Scherzo SS-C18; Imtakt) for the simultaneous quantification of various uremic toxins (UTx), including creatinine, 1-methyladenosine, trimethylamine-N-oxide, indoxyl sulfate, p-cresyl sulfate, phenyl sulfate and 4-ethylphenyl sulfate...
October 5, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
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