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https://www.readbyqxmd.com/read/28636230/quantification-of-fatty-acids-in-erythrocytes-and-plasma-by-fast-gas-chromatography
#1
Cristina Cruz-Hernandez, Sagar K Thakkar, Isabelle Masserey-Elmelegy, William Bousi, Patric Fontannaz, Francesca Giuffrida
As a result of the heterogeneous nature of lipid classes in complex biological matrices such as plasma and erythrocytes, it is imperative to have a robust and validated methodology for fatty acid quantification. The effective method presented here combines available methodology of fast gas chromatography and an improvement of the sample preparation methodology before injection into the gas chromatograph. This methodology ensures complete transesterification and quantification of total and individual fatty acids (and not only in relative amounts) by addition of internal standards...
June 21, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28634067/magnetic-graphene-coated-inorganic-organic-hybrid-nanocomposite-for-enhanced-preconcentration-of-selected-pesticides-in-tomato-and-grape
#2
Hamid Rashidi Nodeh, Hassan Sereshti, Hamid Gaikani, Muhammad Afzal Kamboh, Zahra Afsharsaveh
The new magnetic graphene based hybrid silica-N-[3-(trimethoxysilyl)propyl]ethylenediamine (MG@SiO2-TMSPED) nanocomposite was synthesized via sol-gel process, and used as an effective adsorbent in magnetic solid phase extraction (MSPE) of three selected pesticides followed by gas chromatography micro-electron capture detection (GC-μECD). The adsorbent was characterized using Fourier transform-infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDXS) techniques...
June 13, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28633967/the-effects-of-chronic-faah-inhibition-on-myocardial-lipid-metabolism-in-normotensive-and-doca-salt-hypertensive-rats
#3
Agnieszka Polak, Ewa Harasim-Symbor, Barbara Malinowska, Irena Kasacka, Anna Pędzińska-Betiuk, Jolanta Weresa, Adrian Chabowski
AIMS: There is significant evidence that the endocannabinoid system (ECS) takes part in the regulation of the cardiovascular system in hypertension. It is quite well established that hypertension causes several changes in the heart metabolism, but it is still unknown whether the ECS affects this process. Therefore, we investigated the influence of prolonged ECS activation on myocardial lipid metabolism in deoxycorticosterone acetate (DOCA)-salt hypertensive rats by chronic fatty acid amide hydrolase (FAAH) inhibition...
June 17, 2017: Life Sciences
https://www.readbyqxmd.com/read/28633539/a-survey-on-chemical-constituents-and-indications-of-aromatic-waters-soft-drinks-hydrosols-used-in-persian-nutrition-culture-and-folk-medicine-for-neurological-disorders-and-mental-health
#4
Azadeh Hamedi, Ardalan Pasdaran, Zahra Zebarjad, Mahmoodreza Moein
In Persian nutrition culture, drinking aromatic waters (hydrosols, distillate) has a long history as functional beverages or therapeutic remedies. The co-distilled water with essential oils, which contains partial amounts of more water-soluble volatile compounds are diluted and used as beverages. Since the solubility of volatile components is different in water, the overall composition, and thus the biological activities of aromatic waters seem to be different from the essential oils they were co-distilled with...
January 1, 2017: Journal of Evidence-based Complementary & Alternative Medicine
https://www.readbyqxmd.com/read/28633530/essential-oil-composition-of-rydingia-michauxii-briq-scheen-v-a-albert-endemic-of-iran
#5
Akbar Karami, Hassan Esmaeili, Donya Shahbazian
The chemical composition of the essential oil (EO) obtained from the aerial parts of Rydingia michauxii (Briq.) Scheen & V.A. Albert was analysed by gas chromatography and gas chromatography/mass spectrometry (GC/MS). Eighty components were identified in the oil with caryophyllene oxide (20.1%), trans-verbenol (10.2%), linalool (5.3%) and humulene epoxide II (4.6%) as main constituents. We reported here the chemical compositions of R. michauxii EOs from southern Zagros of Iran with a distinct chemical profile for the first time...
June 20, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28633314/qualitative-identification-of-fentanyl-analogs-and-other-opioids-in-postmortem-cases-by-uhplc-ion-trap-msn
#6
Elisa N Shoff, M Elizabeth Zaney, Joseph H Kahl, George W Hime, Diane M Boland
Since 2013, the Miami-Dade County Medical Examiner Department has experienced an increase in the number of opioid-related deaths. The majority of cases coincided with the introduction of fentanyl into the local heroin supply. From 2014 to 2015, Miami-Dade County experienced a near 600% increase in fentanyl-related deaths, followed by an additional 200% increase in 2016. In 2015, two novel fentanyl analogs were identified in medical examiner cases: beta-hydroxythiofentanyl and acetyl fentanyl. In 2016, four additional fentanyl analogs emerged: para-fluoroisobutyryl fentanyl, butyryl fentanyl, furanyl fentanyl and carfentanil, as well as the synthetic opioid U-47700...
June 13, 2017: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28633145/urinary-volatile-organic-compounds-as-potential-biomarkers-in-idiopathic-membranous-nephropathy
#7
Mingao Wang, Rujuan Xie, Xibei Jia, Ruichan Liu
OBJECTIVE: To detect urinary volatile organic compounds (VOCs) in patients with idiopathic membranous nephropathy (iMN) and normal controls, and whether or not the urinary VOCs can act as biomarkers for diagnosis of iMN independent of renal biopsy. MATERIALS AND METHODS: Gas chromatography/mass spectrometry (GC/MS) was used to assess the urine collected from 63 iMN patients and 15 normal controls. The statistical methods of principal component analysis (PCA) and partial least squares discriminant analysis (PLSDA) were performed to process the final data in CDF format which were converted from GC/MS data...
June 19, 2017: Medical Principles and Practice: International Journal of the Kuwait University, Health Science Centre
https://www.readbyqxmd.com/read/28632902/impaired-hippocampal-glucose-metabolism-during-and-after-flurothyl-induced-seizures-in-mice-reduced-phosphorylation-coincides-with-reduced-activity-of-pyruvate-dehydrogenase
#8
Tanya S McDonald, Karin Borges
OBJECTIVE: To determine changes in glucose metabolism and the enzymes involved in the hippocampus ictally and postictally in the acute mouse flurothyl seizure model. METHODS: [U-(13) C]-Glucose was injected (i.p.) prior to, or following a 5 min flurothyl-induced seizure. Fifteen minutes later, mice were killed and the total metabolite levels and % (13) C enrichment were analyzed in the hippocampal formation using gas chromatography-mass spectrometry. Activities of key metabolic and antioxidant enzymes and the phosphorylation status of pyruvate dehydrogenase were measured, along with lipid peroxidation...
June 20, 2017: Epilepsia
https://www.readbyqxmd.com/read/28632510/itraq-based-quantitative-proteomic-analysis-of-lungs-in-murine-polymicrobial-sepsis-with-hydrogen-gas-treatment
#9
Yingxue Bian, Chao Qin, Yuchang Xin, Yang Yu, Hongguang Chen, Guolin Wang, Keliang Xie, Yonghao Yu
Sepsis-associated acute lung injury (ALI), which carries a high morbidity and mortality in patients, has no effective therapeutic strategies to date. Our group have already reported that hydrogen gas (H2) exerts a protective effect against sepsis in mice. However, the molecular mechanisms underlying H2 treatment are not fully understood. This study investigated the effects of H2 on lung injuries in septic mice through the iTRAQ-based quantitative proteomic analysis. Male ICR mice used in this study were subjected to cecal ligation and puncture (CLP) or sham operation...
June 19, 2017: Shock
https://www.readbyqxmd.com/read/28631877/identification-of-chemical-components-in-baidianling-capsule-based-on-gc-ms-and-hplc-combined-with-fourier-transform-ion-cyclotron-resonance-mass-spectrometry
#10
Wenying Wu, Yu Chen, Binjie Wang, Xiaoyang Sun, Ping Guo, Xiaohui Chen
Baidianling Capsule, which is made from 16 Chinese herbs, has been widely used for treating vitiligo clinically. In this study, the sensitive and rapid method has been developed for the analysis of chemical components in Baidianling Capsule by gas chromatography with mass spectrometry in combination with retention indices and high-performance liquid chromatography combined with Fourier transform-ion cyclotron resonance mass spectrometry. Firstly, a total of 110 potential volatile compounds obtained from different extraction procedures including alkanes, alkenes, alkyne, ketones, ethers, aldehydes, alcohols, phenols, organic acids, esters, furan, pyrrole, acid amide, heterocycle and oxide were detected from Baidianling Capsule by gas chromatography with mass spectrometry, of which 75 were identified by mass spectrometry in combination with the retention index...
June 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28631525/polyphenol-profile-by-uhplc-ms-ms-anti-glycation-antioxidant-and-cytotoxic-activities-of-several-samples-of-propolis-from-the-northeastern-semi-arid-region-of-brazil
#11
Jadriane de Almeida Xavier, Iara Barros Valentim, Fabiana O S Camatari, Alberto M M de Almeida, Henrique Fonseca Goulart, Jamylle Nunes de Souza Ferro, Emiliano de Oliveira Barreto, Bruno Coelho Cavalcanti, Carla B G Bottoli, Marília Oliveira Fonseca Goulart
CONTEXT: Propolis has promising biological activities. Propolis samples from the Northeast of Bahia, Brazil - sample A from Ribeira do Pombal and B, from Tucano - were investigated, with new information regarding their biological activities. OBJECTIVE: This paper describes the chemical profile, antioxidant, anti-glycation and cytotoxic activities of these propolis samples. MATERIAL AND METHODS: Ethanol extracts of these propolis samples (EEP) and their fractions were analyzed to determine total phenolic content (TPC); antioxidant capacity through DPPH(•), FRAP and lipid peroxidation; anti-glycation activity, by an in vitro glucose (10 mg/mL) bovine serum albumine (1 mg/mL) assay, during 7 d; cytotoxic activity on cancer (SF295, HCT-116, OVCAR-8, MDA-MB435, MX-1, MCF7, HL60, JURKAT, MOLT-4, K562, PC3, DU145) and normal cell lines (V79) at 0...
December 2017: Pharmaceutical Biology
https://www.readbyqxmd.com/read/28631411/function-of-bacterial-community-dynamics-in-the-formation-of-cadaveric-semiochemicals-during-in-situ-carcass-decomposition
#12
Javier Pascual, Christian von Hoermann, Ann-Marie Rottler-Hoermann, Omer Nevo, Alicia Geppert, Johannes Sikorski, Katharina J Huber, Sandra Steiger, Manfred Ayasse, Jörg Overmann
The decomposition of dead mammalian tissue involves a complex temporal succession of epinecrotic bacteria. Microbial activity may release different cadaveric volatile organic compounds which in turn attract other key players of carcass decomposition such as scavenger insects. To elucidate the dynamics and potential functions of epinecrotic bacteria on carcasses, we monitored bacterial communities developing on still-born piglets incubated in different forest ecosystems by combining high-throughput Illumina 16S rRNA sequencing with gas chromatography-mass spectrometry of volatiles...
June 19, 2017: Environmental Microbiology
https://www.readbyqxmd.com/read/28631384/nmr-study-of-the-reductive-decomposition-of-bmim-ntf2-at-gold-electrodes-and-indirect-electrochemical-conversion-of-co2
#13
Roman Michez, Thomas Doneux, Claudine Buess-Herman, Michel Luhmer
Potential controlled electrolyses of [BMIm][NTf2 ] ionic liquid were performed at a gold cathode under nitrogen atmosphere. The structures of the major conversion products of the BMIm(+) cation were elucidated on the basis of 1D and 2D nuclear magnetic resonance (NMR) analyses and gas chromatography (GC) analysis of the volatile compounds. Recombination of the imidazol-2-yl radicals, generated at the electrode by single electron transfer, leads to neutral diastereomeric dimers in equal proportions, with a faradaic efficiency of 80 %, while disproportionation of these radicals and/or reaction with hydrogen atoms adsorbed at the electrode generates a neutral monomer with 20 % faradaic efficiency...
June 20, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28631111/suffocation-caused-by-plastic-wrap-covering-the-face-combined-with-nitrous-oxide-inhalation
#14
Peter Mygind Leth, Birgitte Schmidt Astrup
Suicide using a combination of a plastic bag over the head and inhalation of a non-irritating gas, such as helium, argon or nitrogen, has been reported in the literature. Here an unusual suicide method in a 17-year old man by suffocation from covering the face with household plastic wrap, combined with nitrous oxide inhalation, is presented. The case was reviewed based on police, autopsy and hospital reports. A PubMed search for scientific literature related to nitrous oxide abuse and suicide by suffocation was performed and our findings discussed in relation to the scientific literature found...
June 19, 2017: Forensic Science, Medicine, and Pathology
https://www.readbyqxmd.com/read/28629937/the-multi-mode-modulator-a-versatile-fluidic-device-for-two-dimensional-gas-chromatography
#15
John V Seeley, Nicolaas E Schimmel, Stacy K Seeley
A fluidic device called the multi-mode modulator (MMM) has been developed for use as a comprehensive two-dimensional gas chromatography (GC x GC) modulator. The MMM can be employed in a wide range of capacities including as a traditional heart-cutting device, a low duty cycle GC x GC modulator, and a full transfer GC x GC modulator. The MMM is capable of producing narrow component pulses (widths <50ms) while operating at flows compatible with high resolution chromatography. The sample path of modulated components is confined to the interior of a joining capillary...
June 13, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28629236/advances-in-new-psychoactive-substances-identification-the-u-r-i-to-n-consortium
#16
Elisabetta Bertol, Fabio Vaiano, Francesco Mari, Maria Grazia Di Milia, Silvia Bua, Claudiu T Supuran, Fabrizio Carta
Identification of new psychoactive substances (NPS) in biological and non-biological samples represents a hard challenge for forensic toxicologists. Their great chemical variety and the speed with which new NPS are synthesised and spread make stringent the need of advanced tools for their detection based on multidisciplinary approaches. For this reason, in August 2016, the "Unit of Research and Innovation in Forensic Toxicology and Neuroscience of Addiction" (U.R.I.To.N.) was founded by the Forensic Toxicology Division of the University of Florence...
December 2017: Journal of Enzyme Inhibition and Medicinal Chemistry
https://www.readbyqxmd.com/read/28629219/thermally-induced-generation-of-desirable-aroma-active-compounds-from-the-glucosinolate-sinigrin
#17
Eva Ortner, Michael Granvogl
Glucosinolates are the most abundant secondary sulfur-containing plant metabolites in the plant family of Brassicaceae. These phytochemicals are well-known for their enzymatic degradation induced by the enzyme myrosinase resulting in pungent odor impressions derived from their respective degradation products. However, up to now, only little attention has been paid to non-enzymatic thermal degradation and the release of additional aroma-active compounds. Thermal treatment is particularly important in the processing of Brassica vegetables, and, thereby, glucosinolates as precursors can act as a natural source of odorants...
June 20, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28629123/sensory-characteristics-and-volatile-components-of-dry-dog-foods-manufactured-with-sorghum-fractions
#18
Brizio Di Donfrancesco, Kadri Koppel
Descriptive sensory analysis and gas chromatography-mass spectrometry (GC-MS) with a modified headspace solid-phase microextraction (SPME) method was performed on three extruded dry dog food diets manufactured with different fractions of red sorghum and a control diet containing corn, brewer's rice, and wheat as a grain source in order to determine the effect of sorghum fractions on dry dog food sensory properties. The aroma compounds and flavor profiles of samples were similar with small differences, such as higher toasted aroma notes, and musty and dusty flavor in the mill-feed sample...
June 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28626996/vortex-ultrasound-assisted-dispersive-liquid-liquid-microextraction-coupled-with-gc-ms-for-the-analysis-of-volatile-bioactive-components-and-comparative-pharmacokinetic-study-of-the-herb-herb-interactions-in-guanxin-shutong-capsule
#19
Jingqing Mu, Xun Gao, Qing Li, Xiaomei Yang, Wenling Yang, Xu Sun, Kaishun Bi, Huifen Zhang
Guanxin Shutong Capsule, an effective traditional Chinese medicine, is widely used for coronary heart disease clinically. Volatile components are one of its important bioactive constituents. To better understand the material basis for the therapeutic effects, the components of Guanxin Shutong Capsule absorbed into the blood and their metabolites were identified based on gas chromatography with mass spectrometry coupled with vortex-ultrasound-assisted dispersive liquid-liquid microextraction. As a result, three prototypes and 15 metabolites were identified or tentatively characterized in rat plasma...
June 19, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28626990/exhaled-breath-profiles-in-the-monitoring-of-loss-of-control-and-clinical-recovery-in-asthma
#20
Paul Brinkman, Marianne A van de Pol, Marije G Gerritsen, Lieuwe D Bos, Tamara Dekker, Barbara S Smids, Anirban Sinha, Christof J Majoor, Marlous M Sneeboer, Hugo H Knobel, Teunis J Vink, Frans H de Jongh, René Lutter, Peter J Sterk, Niki Fens
BACKGROUND: Asthma is a chronic inflammatory airway disease, associated with episodes of exacerbations. Therapy with inhaled corticosteroids (ICS) targets airway inflammation, which aims to maintain and restore asthma control. Clinical features are only modestly associated with airways inflammation. Therefore, we hypothesized that exhaled volatile metabolites identify longitudinal changes between clinically stable episodes and loss of asthma control. OBJECTIVES: To determine whether exhaled volatile organic compounds (VOCs) as measured by gas-chromatography / mass-spectrometry (GC/MS) and electronic nose (eNose) technology discriminate between clinically stable and unstable episodes of asthma...
June 19, 2017: Clinical and Experimental Allergy: Journal of the British Society for Allergy and Clinical Immunology
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