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https://www.readbyqxmd.com/read/28934974/blood-hemoglobin-a1c-levels-and-amyotrophic-lateral-sclerosis-survival
#1
Qian-Qian Wei, Yongping Chen, Bei Cao, Ru Wei Ou, Lingyu Zhang, Yanbing Hou, Xiang Gao, Huifang Shang
BACKGROUND: There are inconsistences regarding the correlation between diabetes or fasting blood glucose concentrations and the risk and survival of amyotrophic lateral sclerosis (ALS) in the previous studies. Moreover, the association between hemoglobin A1c (HbA1c) levels, which reflect long-term glycemic status, and ALS survival was not examined. METHODS: A prospective cohort study including 450 Chinese sporadic ALS patients (254 men and 196 women; mean age: 55...
September 21, 2017: Molecular Neurodegeneration
https://www.readbyqxmd.com/read/28933014/size-exclusion-chromatography-ion-mobility-mass-spectrometry-coupling-a-step-toward-structural-biology
#2
Guillaume Van der Rest, Frédéric Halgand
Noncovalent interactions are essential for the structural organization of biomacromolecules in cells. For this reason, the study of the biophysical, dynamic, and architectural interactions among biomacromolecules is essential. Since mass spectrometry requires compatible solutions while preserving the noncovalent bonding network, we envisioned that size exclusion chromatography coupled with ion mobility and mass spectrometry would be a valuable technique to desalt the initial sample and provide solution and gas-phase structural information in a single stage experiment...
September 20, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28932891/identification-of-terpenes-and-essential-oils-by-means-of-static-headspace-gas-chromatography-ion-mobility-spectrometry
#3
Roman Rodríguez-Maecker, Eduardo Vyhmeister, Stefan Meisen, Antonio Rosales Martinez, Andriy Kuklya, Ursula Telgheder
Static headspace gas chromatography-ion mobility spectrometry (SHS GC-IMS) is a relatively new analytical technique that has considerable potential for analysis of volatile organic compounds (VOCs). In this study, SHS GC-IMS was used for the identification of the major terpene components of various essential oils (EOs). Based on the data obtained from 25 terpene standards and 50 EOs, a database for fingerprint identification of characteristic terpenes and EOs was generated utilizing SHS GC-IMS for authenticity testing of fragrances in foods, cosmetics, and personal care products...
September 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28931430/global-proteomic-profiling-of-yersinia-ruckeri-strains
#4
Gokhlesh Kumar, Karin Hummel, Timothy J Welch, Ebrahim Razzazi-Fazeli, Mansour El-Matbouli
Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM) of salmonids. There is little information regarding the proteomics of Y. ruckeri. Herein, we perform whole protein identification and quantification of biotype 1 and biotype 2 strains of Y. ruckeri grown under standard culture conditions using a shotgun proteomic approach. Proteins were extracted, digested and peptides were separated by a nano liquid chromatography system and analyzed with a high-resolution hybrid triple quadrupole time of flight mass spectrometer coupled via a nano ESI interface...
September 20, 2017: Veterinary Research
https://www.readbyqxmd.com/read/28931179/evaluation-of-the-interference-of-hemoglobin-variant-j-bangkok-on-glycated-hemoglobin-hba1c-measurement-by-five-different-methods
#5
Dong-Mei Wen, Sheng-Nan Xu, Wei-Jia Wang, Xiu-Ming Zhang, Ming-Huan Suo, De-Cai Zhang
Objective The interference of the hemoglobin variant (Hb J-Bangkok) was evaluated on 4 different glycated hemoglobin assays and compared with a reference immuno assay. Methods An overall test of coincidence of 2 least-squares linear regression lines was performed to determine whether the presence of Hb J-Bangkok caused a statistically significant difference in HbA1c results compared with a reference immuno assay. Statistical analysis was performed on the difference of the estimated average glucose calculated from HbA1c values and fasting plasma glucose in the Hb J-Bangkok variant group using the different detection systems...
September 20, 2017: Experimental and Clinical Endocrinology & Diabetes
https://www.readbyqxmd.com/read/28931050/saxs-and-stability-studies-of-iron-induced-oligomers-of-bacterial-frataxin-cyay
#6
Mostafa Fekry, Wessen Alshokry, Przemysław Grela, Marek Tchórzewski, Eva-Christina Ahlgren, Christopher A Söderberg, Oleksandr Gakh, Grazia Isaya, Salam Al-Karadaghi
Frataxin is a highly conserved protein found in both prokaryotes and eukaryotes. It is involved in several central functions in cells, which include iron delivery to biochemical processes, such as heme synthesis, assembly of iron-sulfur clusters (ISC), storage of surplus iron in conditions of iron overload, and repair of ISC in aconitase. Frataxin from different organisms has been shown to undergo iron-dependent oligomerization. At least two different classes of oligomers, with different modes of oligomer packing and stabilization, have been identified...
2017: PloS One
https://www.readbyqxmd.com/read/28929691/-deuterated-surrogate-and-uplc-ms-ms-method-for-simultaneous-determination-of-22-endocannabinoids-in-ovariectomized-rat-plasma
#7
Shi-Xie Xiang, Ying Xu, Jing-Jing Zhu, Zhi-Min Wang, Dong Zhang, Liang-Mian Chen, Wei-Hong Feng
A new method based on ultraperformance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) was developed for the simultaneous determination of 22 endocannabinoids(eCBs) and relevant compounds in ovariectomized rat plasma. After being extracted by solid-phase column(SPE), the plasma samples were detected by using UPLC-MS/MS. Analysis was carried out with ACQUITY UPLC BEH C₁₈ column. The mobile phase was 0.1% acetic acid solution(A)-acetonitrile and isopropanol(9∶1, B) for the gradient elution. In the positive ion multiple reaction monitoring(MRM) mode, deuterated reagents were taken as standard alternatives to calculate recoveries and simultaneously quantify 22 endocannabinoids...
November 2016: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/28929588/bioactive-compounds-of-shuang-huang-lian-prescription-and-an-insight-into-its-binding-mechanism-by-%C3%AE-2-adrenoceptor-chromatography-coupled-with-site-directed-molecular-docking
#8
Jing Wang, Fengwu Li, Kaizhu Zeng, Qian Li, Xinfeng Zhao, Xiaohui Zheng
Owing to the promising clinical efficacy and relatively simple composition, Shuang-Huang-Lian prescription is widely prescribed for the treatment of acute upper respiratory tract infection and acute bronchitis in practice. This necessitates the understanding of the bioactive compounds of the prescription and their binding mechanism to β2-adrenoceptor, which mediates the aforementioned ailments. In this work, a column containing immobilized β2-adrenoceptor was prepared using a diazonium salt reaction. The bioactive compound collected from the β2-adrenoceptor column was identified as chlorogenic acid by using high-performance liquid chromatography coupled with ion trap mass spectrometry...
September 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28929549/uplc-qtof-ms-e-based-diagnostic-product-ion-filtering-to-unveil-unstable-c6-c2-glucoside-conjugates-in-forsythia-suspensa
#9
Yong-Gang Xia, Jun Liang, Xin-Dong Guo, Hui-Min Sun, Hai-Xue Kuang
Forsythia suspensa contains C6 -C2 glucoside conjugates (CCGCs) that are chemically unstable, thereby hindering their isolation and purification. In the present study, ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF) was utilized to screen and identify unstable CCGCs in the fruits and leaves of F. suspensa without any tedious isolation and purified process based on independent information acquisition (also called MS(E) ) and individual MS/MS experiments. Diagnostic product ion filtering (DPIF) was further applied to mine unknown analogs in MS(E) high energy levels based on characteristic m/z of key substructures...
September 20, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28927592/preliminary-structural-characterization-and-hypoglycemic-effects-of-an-acidic-polysaccharide-serp1-from-the-residue-of-sarcandra-glabra
#10
Wei Liu, Weisheng Lu, Yin Chai, Yameng Liu, Wenbing Yao, Xiangdong Gao
An acidic polysaccharide (SERP1) was isolated from the residue of Sarcandra glabra (Thunb.) Nakai by water extraction and purified by decoloration and ion exchange chromatography. The structure of SERP1 was determined by HPLC, HPSEC-MALLS, FT-IR, and NMR. The results indicated that SERP1 was a homogeneous heteropolysaccharide with the absolute molecular weight of 4.208×10(4)Da in the aqueous phase. 1,4-linked α-d-galacturonic acid, methyl esterified 1,4-linked α-d-galacturonic acid, 1,4-linked α-d-glucuronic acid, 1,5-linked α-l-arabinose, 1,3-linked β-d-galactose 1,4-linked α-d-glucose, 1,4,6-linked β-d-glucose, 1,6-linked β-d-glucose, and 1,2-linked rhamnose existed in SERP1...
November 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28927165/air-and-surface-sampling-method-for-assessing-exposures-to-quaternary-ammonium-compounds-using-liquid-chromatography-tandem-mass-spectrometry
#11
Ryan F LeBouf, Mohammed Abbas Virji, Anand Ranpara, Aleksandr B Stefaniak
This method was designed for sampling select quaternary ammonium (quat) compounds in air or on surfaces followed by analysis using ultraperformance liquid chromatography tandem mass spectrometry. Target quats were benzethonium chloride, didecyldimethylammonium bromide, benzyldimethyldodecylammonium chloride, benzyldimethyltetradecylammonium chloride, and benzyldimethylhexadecylammonium chloride. For air sampling, polytetrafluoroethylene (PTFE) filters are recommended for 15-min to 24-hour sampling. For surface sampling, Pro-wipe® 880 (PW) media was chosen...
July 1, 2017: Annals of Work Exposures and Health
https://www.readbyqxmd.com/read/28926698/quantification-of-lignin-and-its-structural-features-in-plant-biomass-using-13-c-lignin-as-internal-standard-for-pyrolysis-gc-sim-ms
#12
Gijs van Erven, Ries de Visser, Donny W H Merkx, Willem Strolenberg, Peter De Gijsel, Harry Gruppen, Mirjam A Kabel
Understanding mechanisms underlying plant biomass recalcitrance at molecular level can only be achieved by accurate analyses of both content and structural features of the molecules involved. Current quantification of lignin is, however, majorly based on unspecific gravimetric analysis after sulphuric acid hydrolysis. Hence, our research aimed at specific lignin quantification with concurrent characterization of its structural features. Hereto, for the first time, a polymeric (13)C lignin was used as internal standard (IS) for lignin quantification via analytical pyrolysis coupled to gas chromatography with mass-spectrometric detection in selected ion monitoring mode (py-GC-SIM-MS)...
September 19, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28924329/a-computational-tool-for-accelerated-analysis-of-oligomeric-proanthocyanidins-in-plants
#13
Mengliang Zhang, Jianghao Sun, Pei Chen
A computational tool was developed to facilitate proanthocyanidin analysis using data collected by ultra-high-performance liquid chromatography-diode array detection-high resolution accurate mass-mass spectrometry (UHPLC-DAD-HRAM-MS). Both identification and semi-quantitation of proanthocyanidins can be achieved by the developed computational tool. It can extract proanthocyanidin chromatographic peaks, deconvolute the isotopic patterns of A-type, B-type, and multi-charged proanthocyanidins ions, and predict proanthocyanidin structures...
March 2017: Journal of Food Composition and Analysis
https://www.readbyqxmd.com/read/28922607/antdas-automatic-data-analysis-strategy-for-uplc-qtof-based-nontargeted-metabolic-profiling-analysis
#14
Hai-Yan Fu, Xiao-Ming Guo, Yue-Ming Zhang, Jing-Jing Song, Qing-Xia Zheng, Ping-Ping Liu, Peng Lu, Qian-Si Chen, Yong-Jie Yu, Yuanbin She
High-quality data analysis methodology remains a bottleneck for metabolic profiling analysis based on ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The present work aims to address this problem by proposing a novel data analysis strategy wherein (1) chromatographic peaks in the UPLC-QTOF dataset are automatically extracted by using an advanced multiscale Gaussian smoothing-based peak extraction strategy. (2) A peak annotation stage is used to cluster fragment ions that belong to the same compound...
September 18, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28922569/strategies-for-analysis-of-isomeric-peptides
#15
Erik T Jansson
This review presents an overview and recent progress of strategies for detecting isomerism in peptides, with focus on d/l epimerization and the various isomers that the presence of an aspartic acid residue may yield in a protein or peptide. While mass spectrometry has become a majorly used method of choice within proteomics, isomerism is inherently difficult to analyze because it is a modification that does not yield any change in mass of the analyte. Here, several techniques used for analysis of peptide isomerism are discussed, including enzymatic assays, liquid chromatography and capillary electrophoresis...
September 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28921605/simple-determination-of-betaine-l-carnitine-and-choline-in-human-urine-using-self-packed-column-and-column-switching-ion-chromatography-with-non-suppressed-conductivity-detection
#16
Dan Wei, Yan Zhu, Ming Guo
A sequential on-line extraction, clean-up and separation system for the determination of betaine, L-carnitine and choline in human urine using column-switching ion chromatography with non-suppressed conductivity detection was developed in this work. Self-packed pretreatment column (50 mm×4.6 mm, i.d.) was used for the extraction and clean-up of betaine, L-carnitine and choline. The separation was achieved using self-packed cationic exchange column (150 mm×4.6 mm, i.d.), followed by non-suppressed conductivity detection...
September 15, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28921438/purification-methods-for-recombinant-factor-viii-expressed-in-human-liver-sk-hep-cells
#17
Vladimir Granovski, Mario Soares Abreu-Neto, Dimas Tadeu Covas
Coagulation factor VIII is one of the largest proteins attempted to be expressed in recombinant form. A very complex and labile protein which has a very short half-live and need a fast and efficient purification chain. Here, we describe a simple purification sequence using multimodal Capto MMC, affinity FVIII select and ion exchange SP-Fastflow chromatography steps without subjecting the target molecule to mechanical and temperature stress, separating impurities from rFVIII using net charge, hydrophobicity, and affinity of the molecules...
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28919250/purification-and-characterization-of-a-cellulase-free-thermostable-endo-xylanase-from-streptomyces-griseorubens-lh-3-and-its-use-in-biobleaching-on-eucalyptus-kraft-pulp
#18
Hao Wu, Xianbo Cheng, Yongfeng Zhu, Wei Zeng, Guiguang Chen, Zhiqun Liang
Xylanase is an important enzyme involved in degrading xylan. In this study, an extracellular cellulase-free, thermostable endo-xylanase which was produced by Streptomyces griseorubens LH-3 with bagasse semi-cellulose as a carbon source was purified and characterized. The xylanase was purified 4-fold with a recovery yield of 21.6% by precipitation with 25-55% (NH4)2SO4, Mono Q ion exchange chromatography and sephacryl S-200 HR gel filtration chromatography. It appeared as a monomeric protein on SDS-PAGE gel and had an apparent molecular weight of 45...
September 14, 2017: Journal of Bioscience and Bioengineering
https://www.readbyqxmd.com/read/28918855/ion-pair-in-tube-solid-phase-microextraction-for-the-simultaneous-determination-of-phthalates-and-their-degradation-products-in-atmospheric-particulate-matter
#19
M Fernández-Amado, M C Prieto-Blanco, P López-Mahía, S Muniategui-Lorenzo, D Prada-Rodríguez
An in-tube solid phase microextraction, coupled with high-performance liquid chromatography with diode array detection (IT-SPME-HPLC-DAD) method, has been developed for the simultaneous determination of 13 diesters (from dimethyl to dioctylphthalate plus diisobutyl, benzylbutyl, di-2-ethylhexyl, diisononyl and diisodecylphthalate) and 2 monoesters of phthalic acid (mono-butyl and mono-(2-ethylhexyl) phthalate) in particulate matter (PM10). Triethylamine at pH=3 was used as an ion-pair reagent with a double function, of regulating the chromatographic retention of the monoesters and the most hydrophilic diesters on a monolithic silica column, and of improving their extraction on a porous polymer with divinylbenzene-4-vinylpyridine capillary...
September 6, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28918593/decline-patterns-and-risk-assessment-of-10-multi-class-pesticides-in-young-sprout-amaranth-amaranthus-mangostanus-under-greenhouse-growing-conditions
#20
In Kyung Kim, Sung-Woo Kim, A M Abd El-Aty, Md Musfiqur Rahman, Md Humayun Kabir, Han Sol Lee, Hyung Suk Chung, Ji Hoon Jeong, Ho-Chul Shin, Jae-Han Shim
The present study was designed to investigate the residual decline pattern and the risk assessment of 10 different class pesticides, namely azoxystrobin, boscalid, diazinon, diethofencarb, difenoconazole, etofenprox, flubendiamide, paclobutrazol, and pyraclostrobin in young vegetative amaranth (Amaranthus mangostanus) sprayed once or twice under greenhouse growing conditions. Field-incurred samples, collected at 3, 7, or 10 days after application of both treatments, were extracted and purified with the quick, easy, cheap, effective, rugged, and safe "QuEChERS" citrate-buffered method and analyzed with liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS) in positive ion mode...
September 16, 2017: Environmental Science and Pollution Research International
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