keyword
MENU ▼
Read by QxMD icon Read
search

gas chromatography

keyword
https://www.readbyqxmd.com/read/27926460/association-of-serum-n-3-polyunsaturated-fatty-acids-with-psychological-distress-in-the-second-and-third-trimesters-of-pregnancy-adjunct-study-of-japan-environment-and-children-s-study
#1
Kei Hamazaki, Akiko Harauma, Satoru Tanabe, Miho Namai, Toru Moriguchi, Hidekuni Inadera
The results of several epidemiological studies and clinical trials investigating the effects of n-3 polyunsaturated fatty acids (PUFAs) on antenatal and postnatal depression remain controversial. In a previous case-control study of early pregnancy in Japan, we found an inverse association between eicosapentaenoic acid and risk of psychological distress after adjusting for possible confounders. Here, in a 1:2 matched case-control study, we further investigated the possible relationship between serum n-3 PUFAs and risk of psychological distress in the second and third trimesters of pregnancy...
November 2016: Prostaglandins, Leukotrienes, and Essential Fatty Acids
https://www.readbyqxmd.com/read/27926458/changes-in-relative-and-absolute-concentrations-of-plasma-phospholipid-fatty-acids-observed-in-a-randomized-trial-of-omega-3-fatty-acids-supplementation-in-uganda
#2
Xiaoling Song, Pho Diep, Jeannette M Schenk, Corey Casper, Jackson Orem, Zeina Makhoul, Johanna W Lampe, Marian L Neuhouser
Expressing circulating phospholipid fatty acids (PLFAs) in relative concentrations has some limitations: the total of all fatty acids are summed to 100%; therefore, the values of individual fatty acid are not independent. In this study we examined if both relative and absolute metrics could effectively measure changes in circulating PLFA concentrations in an intervention trial. 66 HIV and HHV8 infected patients in Uganda were randomized to take 3g/d of either long-chain omega-3 fatty acids (1856mg EPA and 1232mg DHA) or high-oleic safflower oil in a 12-week double-blind trial...
November 2016: Prostaglandins, Leukotrienes, and Essential Fatty Acids
https://www.readbyqxmd.com/read/27925846/characteristics-sources-and-cytotoxicity-of-atmospheric-polycyclic-aromatic-hydrocarbons-in-urban-roadside-areas-of-hangzhou-china
#3
Hongzhen Bai, Hongjian Zhang
The primary objective of this study is to understand the profiles, sources and cytotoxic effects of atmospheric polycyclic aromatic hydrocarbons (PAHs), which are closely related to urban air contamination and public health, in urban roadside environments. On-road sampling campaigns were conducted from 2014 to 2015 at three urban road sites in Hangzhou, China. Sixteen gaseous and particulate matter (PM) 2.5-bound PAHs were identified and quantified using gas chromatography-mass spectrometry (GC-MS). The total PAH concentrations at the three sites ranged from 750 to1142 ng/m(3) and 1050 to 1483 ng/m(3) in summer and winter, respectively...
December 7, 2016: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
https://www.readbyqxmd.com/read/27925402/two-new-oxygen-containing-biomarkers-isolated-from-the-chinese-maoming-oil-shale-by-silica-gel-column-chromatography-and-preparative-gas-chromatography
#4
Xiangyun Zhang, Hong Lu, Jing Liao, Caiming Tang, Guoying Sheng, Ping'an Peng
Two biomarkers, 5,9-dimethyl-6-isopropyl-2-decanone (1) and 4,9,11-trimethyl-6-isopropyl-2-dodecanone (2), were isolated from Chinese Maoming Oil Shale by silica gel column chromatography and preparative gas chromatography. Their structures were elucidated by using spectroscopic techniques. This article is protected by copyright. All rights reserved.
December 7, 2016: Journal of Separation Science
https://www.readbyqxmd.com/read/27925257/volatile-compounds-produced-by-lactobacillus-paracasei-during-oat-fermentation
#5
Sang Mi Lee, Jieun Oh, Byung-Serk Hurh, Gwi-Hwa Jeong, Young-Keum Shin, Young-Suk Kim
This study investigated the profiles of volatile compounds produced by Lactobacillus paracasei during oat fermentation using gas chromatography-mass spectrometry coupled with headspace solid-phase microextraction method. A total of 60 compounds, including acids, alcohols, aldehydes, esters, furan derivatives, hydrocarbons, ketones, sulfur-containing compounds, terpenes, and other compounds, were identified in fermented oat. Lipid oxidation products such as 2-pentylfuran, 1-octen-3-ol, hexanal, and nonanal were found to be the main contributors to oat samples fermented by L...
December 2016: Journal of Food Science
https://www.readbyqxmd.com/read/27925246/analytical-method-for-urinary-metabolites-as-biomarkers-for-monitoring-exposure-to-phthalates-by-gas-chromatography-mass-spectrometry
#6
Toshiaki Yoshida
Phthalates, widely being used as plasticizers, have been detected from the indoor air of residences, but there have been few reports on methods of analyzing urinary metabolites as biomarkers to monitor exposure to di-n-pentyl phthalate or di-n-hexyl phthalate. Presented here is a cost-effective and sensitive analytical method for the determination of urinary metabolites of phthalates containing these two compounds. Nine urinary phthalate metabolites were enzymatically hydrolyzed and extracted with toluene: monomethyl phthalate, monoethyl phthalate, monoisobutyl phthalate, mono-n-butyl phthalate, mono-n-pentyl phthalate, mono-n-hexyl phthalate, monocyclohexyl phthalate, monobenzyl phthalate and mono(2-ethyl-5-carboxypentyl) phthalate...
December 7, 2016: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/27924918/production-of-phloroglucinol-a-platform-chemical-in-arabidopsis-using-a-bacterial-gene
#7
Salah E Abdel-Ghany, Irene Day, Adam L Heuberger, Corey D Broeckling, Anireddy S N Reddy
Phloroglucinol (1,3,5-trihydroxybenzene; PG) and its derivatives are phenolic compounds that are used for various industrial applications. Current methods to synthesize PG are not sustainable due to the requirement for carbon-based precursors and co-production of toxic byproducts. Here, we describe a more sustainable production of PG using plants expressing a native bacterial or a codon-optimized synthetic PhlD targeted to either the cytosol or chloroplasts. Transgenic lines were analyzed for the production of PG using gas and liquid chromatography coupled to mass spectroscopy...
December 7, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27924835/longitudinal-study-of-pesticide-residue-levels-in-human-milk-from-western-australia-during-12-months-of-lactation-exposure-assessment-for-infants
#8
Jian Du, Zoya Gridneva, Melvin C L Gay, Ching T Lai, Robert D Trengove, Peter E Hartmann, Donna T Geddes
The presence of pesticides in human milk (HM) is of great concern due to the potential health effects for the breastfed infant. To determine the relationships between HM pesticides and infant growth and development, a longitudinal study was conducted. HM samples (n = 99) from 16 mothers were collected at 2, 5, 9 and 12 months of lactation. A validated QuEChERS method and Gas chromatography-tandem mass spectrometry (GC-MS/MS) were used for the analysis of 88 pesticides in HM. Only p,p'-DDE, p,p'-DDT and β-HCH were detected with a mean concentration (±SD) of 52...
December 7, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27923736/genomic-and-phenotypic-analyses-of-serratia-fonticola-strain-gs2-a-rhizobacterium-isolated-from-sesame-rhizosphere-that-promotes-plant-growth-and-produces-n-acyl-homoserine-lactone
#9
Byung Kwon Jung, Abdur Rahim Khan, Sung-Jun Hong, Gun-Seok Park, Yeong-Jun Park, Chang Eon Park, Hwang-Ju Jeon, Sung-Eun Lee, Jae-Ho Shin
The genus Serratia incorporates many agriculturally important species. Serratia fonticola strain GS2, isolated from a sesame rhizosphere, can produce N-acyl homoserine lactone quorum sensing signal molecules and indole-3-acetic acid (IAA). Here we report the complete genome sequence and phenotypic characteristics based on genomic information of this bacterium. The complete genome sequence of S. fonticola strain GS2 consists of a chromosome of 6.1 Mbp and two plasmids of 132 kbp and 94 kbp. The genome clusters for IAA and N-acyl homoserine lactone biosynthesis were identified in the genome...
December 3, 2016: Journal of Biotechnology
https://www.readbyqxmd.com/read/27923571/a-simple-dried-blood-spot-method-for-in-vivo-measurement-of-ureagenesis-by-gas-chromatography-mass-spectrometry-using-stable-isotopes
#10
Gabriella Allegri, Sereina Deplazes, Hiu Man Viecelli, Déborah Mathis, Ralph Fingerhut, Johannes Häberle, Beat Thöny
BACKGROUND: Clinical management of inherited or acquired hyperammonemia depends mainly on the plasma ammonia level which is not a reliable indicator of urea cycle function as its concentrations largely fluctuate. The gold standard to assess ureagenesis in vivo is the use of stable isotopes. METHODS: Here we developed and validated a simplified in vivo method with [(15)N]ammonium chloride ([(15)N]H4Cl) as a tracer. Non-labeled and [(15)N]urea were quantified by GC-MS after extraction and silylation...
December 3, 2016: Clinica Chimica Acta; International Journal of Clinical Chemistry
https://www.readbyqxmd.com/read/27923502/comparison-of-gas-chromatography-mass-spectrometry-and-gas-chromatography-tandem-mass-spectrometry-with-electron-ionization-for-determination-of-n-nitrosamines-in-environmental-water
#11
Wenwen Chen, Xiaoshui Li, Huanfang Huang, Xuetao Zhu, Xiaoyu Jiang, Yuan Zhang, Kuang Cen, Lunshan Zhao, Xiuli Liu, Shihua Qi
N-nitrosamines are trace organic contaminants of environmental concern when present in groundwater and river water due to their potent carcinogenicity. Therefore, N-nitrosamine analysis is increasingly in demand. Gas chromatography-mass spectrometry (GC-MS) and GC-tandem mass spectrometry (GC-MS/MS), both with electron ionization (EI), were compared for analysis of nine N-nitrosamines extracted from environmental water matrices. A total of 20 fishpond water, river water, and groundwater samples from Sihui and Shunde, China were collected for a survey of N-nitrosamine concentrations in real water samples...
December 3, 2016: Chemosphere
https://www.readbyqxmd.com/read/27923272/elimination-of-diazinon-insecticide-from-cucumber-surface-by-atmospheric-pressure-air-dielectric-barrier-discharge-plasma
#12
Naghme Dorraki, Vahideh Mahdavi, Hamid Ghomi, Alireza Ghasempour
The food industry is in a constant search for new technologies to improve the commercial sterilization process of agricultural commodities. Plasma treatment may offer a novel and efficient method for pesticide removal from agricultural product surfaces. To study the proposed technique of plasma food treatment, the degradation behavior of diazinon insecticide by air-dielectric barrier discharge (DBD) plasma was investigated. The authors studied the effect of different plasma powers and treatment times on pesticide concentration in liquid form and coated on the surface of cucumbers, where the diazinon residue was analyzed with mass spectroscopy gas chromatography...
December 6, 2016: Biointerphases
https://www.readbyqxmd.com/read/27920773/glucose-metabolism-via-the-entner-doudoroff-pathway-in-campylobacter-a-rare-trait-that-enhances-survival-and-promotes-biofilm-formation-in-some-isolates
#13
Christina S Vegge, Melissa J Jansen van Rensburg, Janus J Rasmussen, Martin C J Maiden, Lea G Johnsen, Morten Danielsen, Sheila MacIntyre, Hanne Ingmer, David J Kelly
Isolates of the zoonotic pathogen Campylobacter are generally considered to be unable to metabolize glucose due to lack of key glycolytic enzymes. However, the Entner-Doudoroff (ED) pathway has been identified in Campylobacter jejuni subsp. doylei and a few C. coli isolates. A systematic search for ED pathway genes in a wide range of Campylobacter isolates and in the C. jejuni/coli PubMLST database revealed that 1.7% of >6,000 genomes encoded a complete ED pathway, including both C. jejuni and C. coli from diverse clinical, environmental and animal sources...
2016: Frontiers in Microbiology
https://www.readbyqxmd.com/read/27919695/metabolomics-identifies-perturbations-in-amino-acid-metabolism-in-the-prefrontal-cortex-of-the-learned-helplessness-rat-model-of-depression
#14
Xinyu Zhou, Lanxiang Liu, Yuqing Zhang, Juncai Pu, Lining Yang, Chanjuan Zhou, Shuai Yuan, Hanping Zhang, Peng Xie
Major depressive disorder is a serious psychiatric condition associated with high rates of suicide and is a leading cause of health burden worldwide. However, the underlying molecular mechanisms of major depression are still essentially unclear. In our study, a non-targeted gas chromatography-mass spectrometry-based metabolomics approach was used to investigate metabolic changes in the prefrontal cortex of the learned helplessness rat model of depression. Body-weight measurements and behavioral tests including the active escape test, sucrose preference test, forced swimming test, elevated plus-maze and open field test were used to assess changes in the behavioral spectrum after inescapable footshock stress...
December 2, 2016: Neuroscience
https://www.readbyqxmd.com/read/27919518/polydopamine-decorated-3d-nickel-foam-for-extraction-of-sixteen-polycyclic-aromatic-hydrocarbons
#15
Ying Cai, Zhihong Yan, Ming Yang, Xiaoying Huang, Weiping Min, Lijia Wang, Qingyun Cai
In this work, polydopamine coated 3D nickel foam (NF-PDA) was prepared and applied as sorbent for the solid phase extraction (SPE) of 16 polycyclic aromatic hydrocarbons (PAHs) from water samples. NF-PDA were synthesized by situ oxidative self-polymerization procedure and characterized by using the techniques of scanning electron microscopy (SEM), energy dispersive spectrum analysis (EDS) and X-ray photoelectron spectroscopy (XPS). Its performance was evaluated by the SPE of 16 PAHs from water samples, followed by gas chromatography-mass spectrometrical (GC-MS) analysis...
November 21, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27919287/chemical-profiling-antimicrobial-and-insecticidal-evaluations-of-polygonum-hydropiper-l
#16
Muhammad Ayaz, Muhammad Junaid, Farhat Ullah, Abdul Sadiq, Muhammad Ovais, Waqar Ahmad, Sajjad Ahmad, Anwar Zeb
BACKGROUND: The emergence of multidrug resistant (MDR) pathogens is of great concern to the global health community. Our ability to effectively treat diseases is based on the discovery of potent drugs for the treatment of these challenging diseases. Traditional medicines are one of the major sources for the discovery of safe, effective and economical drug candidates. In order to validate its antibacterial, antifungal and insecticidal potentials with respect to traditional uses, we have screened for the first time Polygonum hydropiper against pathogenic bacterial, fungal strains and a variety of insects...
December 5, 2016: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/27919272/enhanced-lipid-and-biomass-production-by-a-newly-isolated-and-identified-marine-microalga
#17
Mouna Dammak, Sandra Mareike Haase, Ramzi Miladi, Faten Ben Amor, Mohamed Barkallah, David Gosset, Chantal Pichon, Bernhard Huchzermeyer, Imen Fendri, Michel Denis, Slim Abdelkafi
BACKGROUND: The increasing demand for microalgae lipids as an alternative to fish has encouraged researchers to explore oleaginous microalgae for food uses. In this context, optimization of growth and lipid production by the marine oleaginous V2-strain-microalgae is of great interest as it contains large amounts of mono-unsaturated (MUFAs) and poly-unsaturated fatty acids (PUFAs). METHODS: In this study, the isolated V2 strain was identified based on 23S rRNA gene...
December 5, 2016: Lipids in Health and Disease
https://www.readbyqxmd.com/read/27918998/simultaneously-determination-of-bisphenol-a-and-its-alternatives-in-sediment-by-ultrasound-assisted-and-solid-phase-extractions-followed-by-derivatization-using-gc-ms
#18
Qiang Wang, Lingyan Zhu, Meng Chen, Xinxin Ma, Xiaolei Wang, Junchao Xia
Bisphenol analogues are a group of chemicals which are being widely applied in industrial and household products owing to regulations on bisphenol A (BPA) in many countries. In this study, an analytical method, including extraction from complex environmental matrices, clean-up using solid phase extraction (SPE) and following-up derivatization prior to gas chromatography coupled with mass spectrometry (GC-MS), was developed to analyze seven commonly used bisphenols in sediment. Five kinds of extraction solvents, four kinds of SPE cartridges, and four kinds of SPE eluting solvents were individually tested for their performances; and the conditions for derivatizing were also optimized...
December 2, 2016: Chemosphere
https://www.readbyqxmd.com/read/27918484/a-novel-wireless-wearable-volatile-organic-compound-voc-monitoring-device-with-disposable-sensors
#19
Yue Deng, Cheng Chen, Xiaojun Xian, Francis Tsow, Gaurav Verma, Rob McConnell, Scott Fruin, Nongjian Tao, Erica S Forzani
A novel portable wireless volatile organic compound (VOC) monitoring device with disposable sensors is presented. The device is miniaturized, light, easy-to-use, and cost-effective. Different field tests have been carried out to identify the operational, analytical, and functional performance of the device and its sensors. The device was compared to a commercial photo-ionization detector, gas chromatography-mass spectrometry, and carbon monoxide detector. In addition, environmental operational conditions, such as barometric change, temperature change and wind conditions were also tested to evaluate the device performance...
December 3, 2016: Sensors
https://www.readbyqxmd.com/read/27917180/role-of-the-gacs-sensor-kinase-in-the-regulation-of-volatile-production-by-plant-growth-promoting-pseudomonas-fluorescens-sbw25
#20
Xu Cheng, Viviane Cordovez, Desalegn W Etalo, Menno van der Voort, Jos M Raaijmakers
In plant-associated Pseudomonas species, the production of several secondary metabolites and exoenzymes is regulated by the GacS/GacA two-component regulatory system (the Gac-system). Here, we investigated if a mutation in the GacS sensor kinase affects the production of volatile organic compounds (VOCs) in P. fluorescens SBW25 (Pf.SBW25) and how this impacts on VOCs-mediated growth promotion and induced systemic resistance of Arabidopsis and tobacco. A total of 205 VOCs were detected by Gas Chromatography Mass Spectrometry for Pf...
2016: Frontiers in Plant Science
keyword
keyword
111794
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"