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https://www.readbyqxmd.com/read/28445860/brephedrone-a-new-psychoactive-substance-seized-in-brazil
#1
Yuri Machado, José Coelho Neto, Paulo Eduardo Nunes Barbosa, Rogério Araújo Lordeiro, Rosemeire Brondi Alves
At the beginning of 2015, sixty-two capsules containing red-brown crystals seized in a historical city in Brazil were sent to this forensic laboratory for drug testing analysis. The material was identified as being Brephedrone, a new psychoactive substance and a bromine synthetic cathinone that is related to serotonin transportation. This substance was analyzed by ATR-FTIR, GC-MS, LC-MS, (1)H, (13)C and 2D NMR. Brephedrone apprehensions have been previously reported in Finland, France and Spain. It was the first detection of this substance in the State of Minas Gerais...
April 15, 2017: Forensic Science International
https://www.readbyqxmd.com/read/28444854/analysis-of-organic-components-in-resin-modified-pulp-capping-materials-critical-considerations
#2
Bo W Nilsen, Einar Jensen, Ulf Örtengren, Vibeke B Michelsen
The purpose of this study was to elucidate the organic composition and eluates of three resin-based pulp-capping materials in relation to their indications and safety data sheets. Uncured samples of Theracal LC, Ultra-Blend Plus, and Calcimol LC were investigated using gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Identification/quantification of 7-d leachables of cured samples was performed using GC-MS for 2-hydroxyethyl methacrylate (HEMA), 2-(dimethylamino)ethyl methacrylate (DMAEMA), camphorquinone (CQ), ethylene glycol dimethacrylate (EGDMA), ethyl-4-(dimethylamino)benzoate (DMABEE), and triethylene glycol dimethacrylate (TEGDMA)...
April 26, 2017: European Journal of Oral Sciences
https://www.readbyqxmd.com/read/28444796/determination-of-volatile-flavour-profiles-of-citrus-spp-fruits-by-sde-gc-ms-and-enantiomeric-composition-of-chiral-compounds-by-mdgc-ms
#3
Joon Ho Hong, Naeem Khan, Nargis Jamila, Young Shin Hong, Eun Yeong Nho, Ji Yeon Choi, Cheong Mi Lee, Kyong Su Kim
INTRODUCTION: Citrus fruits are known to have characteristic enantiomeric key compounds biosynthesised by highly stereoselective enzymatic mechanisms. In the past, evaluation of the enantiomeric ratios of chiral compounds in fruits has been applied as an effective indicator of adulteration by the addition of synthetic compounds or natural components of different botanical origin. OBJECTIVE: To analyse the volatile flavour compounds of Citrus junos Sieb. ex Tanaka (yuzu), Citrus limon BURM...
April 25, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28443078/phytochemical-characterization-of-terminalia-catappa-linn-extracts-and-their-antifungal-activities-against-candida-spp
#4
Analucia G Terças, Andrea de Souza Monteiro, Eduardo B Moffa, Julliana R A Dos Santos, Eduardo M de Sousa, Anna R B Pinto, Paola C da Silva Costa, Antonio C R Borges, Luce M B Torres, Allan K D Barros Filho, Elizabeth S Fernandes, Cristina de Andrade Monteiro
Terminalia catappa Linn bark is used to treat dysentery by various populations in Southeast Asian countries, and its leaves have also been used in traditional medicine to treat hepatitis in India and the Philippines. Here, the antifungal actions of crude hydro-alcoholic extract (TcHE) and fractions from T. catappa leaves were assessed via the agar diffusion and microdilution tests on Candida reference strains and clinical isolates from patients with acquired immunodeficiency syndrome (AIDS). Additionally, the potential cytotoxic effects of TcHE were assessed on cultured human peripheral blood mononuclear cells (PBMC)...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28442412/hsccc-separation-and-enantiomeric-distribution-of-key-volatile-constituents-of-piper-claussenianum-miq-c-dc-piperaceae
#5
André M Marques, Catharina E Fingolo, Maria Auxiliadora C Kaplan
High Speed Countercurrent Chromatography (HSCCC) technique was used for the preparative isolation of the major leishmanicidal compounds from the essential oils of Piper claussenianum species in Brazil. The essential oils from inflorescences of P. claussenianum were analyzed by GC-FID and GC-MS. The enantiomeric ratio of the major constituents of the P. claussenianum essential oils were determined using a Rt-DEXsm chiral capillary column by GC-FID analysis. It was found an enantiomeric excess of (+)-(E)-nerolidol in the leaves, and (+)-linalool and (+)-(E)-nerolidol in the inflorescences essential oil...
April 22, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/28442173/analysis-of-tar-compounds-and-quantification-of-naphthalene-from-thermal-treatment-of-household-biowaste
#6
S Vakalis, F Patuzzi, K Moustakas, A Sotiropoulos, D Malamis, M Baratieri
Household biowaste represent the organic fraction of municipal solid waste and are an underutilized resource. Although previous studies have performed pyrolysis of organic waste, the vast majority has been on specific presorted feedstock or conventional lignocellulosic streams. Therefore, there is a lack of pyrolysis applications on representative food waste as retrieved from households and this can be attributed primarily to their high water content and their degradability. But via the intermediate step of drying, long-term storage and thermal treatment have become possible...
April 22, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28442115/lipase-inhibitory-activity-of-lagenaria-siceraria-fruit-as-a-strategy-to-treat-obesity
#7
Maria Maqsood, Dildar Ahmed, Iqra Atique, Wajeeha Malik
OBJECTIVE: To explore pancreatic lipase inhibitory activity under different extraction conditions in order to track the most potent extract. METHODS: The methanolic extract and its fractions in solvents of increasing polarity, ether, chloroform, ethyl acetate, n-butanol and water, were made through cold maceration. Extracts in ethanol, ethyl acetate, acetone and chloroform were similarly prepared. Aqueous extract was prepared through hot decoction method. A reported method was used to determine lipase inhibitory activity of extracts and fractions over wide ranges of concentrations...
March 2017: Asian Pacific Journal of Tropical Medicine
https://www.readbyqxmd.com/read/28442111/toxicity-assessment-and-screening-of-tetrodotoxin-in-the-oblong-blowfish-takifugu-oblongus-from-the-tamil-nadu-coast-of-bay-of-bengal-india
#8
S M Indumathi, S S Khora
OBJECTIVE: To assess the toxicity of the pufferfish Takifugu oblongus, from Chennai coast, Tamil Nadu, India and to detect the presence of Tetrodotoxin (TTX). METHODS: The toxicity was evaluated by mouse bioassay using Swiss Albino mice which were expressed in mouse units (MU). Gross anatomical features were observed which is followed by histopathology of the dead mice tissues to establish the toxicity. Instrumental analysis for the presence of tetrodotoxin was also performed through GC-MS and HPLC...
March 2017: Asian Pacific Journal of Tropical Medicine
https://www.readbyqxmd.com/read/28441359/relationship-between-expression-of-chalcone-synthase-genes-and-chromones-in-artificial-agarwood-induced-by-formic-acid-stimulation-combined-with-fusarium-sp-a2-inoculation
#9
Xiaodong Chen, Xiaoling Zhu, Meirou Feng, Zhaojian Zhong, Xin Zhou, Xiaoying Chen, Wei Ye, Weimin Zhang, Xiaoxia Gao
Agarwood (gaharu) is a fragrant resin produced in the heartwood of resinous Gyrinops and Aquilaria species. Artificial agarwood samples were obtained from Aquilaria sinensis (Lour.) Gilg using formic acid (FA) stimulation combined with Fusarium sp. A2 inoculation. The relationship between the expression of chalcone synthase genes (CHS) and dynamic changes in chromone content was explored in resin-deposited parts of the trunks of A. sinensis. CHS gene expression levels were detected by qRT-PCR analysis. The chemical composition of agarwood obtained from the heartwood of A...
April 25, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28441028/application-of-gc-ms-soft-ionization-for-isomeric-biological-compound-analysis
#10
Takeshi Furuhashi, Koji Okuda
Isomers are compounds with the same molecular formula. Many different types of isomers are ubiquitous and play important roles in living organisms. Despite their early discovery, the actual analysis of isomers has been tricky and has confounded researchers. Using mass spectrometry (MS) to distinguish or identify isomers is an emergent topic and challenge for analytical chemists. We review some techniques for analyzing isomers with emphasis on MS, e.g., the roles of ion reaction, hydrogen-deuterium exchange, ion mobility mass spectrometry, ion spectroscopy and energy change in producing isomer-specific fragments...
April 25, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28441010/a-new-instrumental-set-up-for-simultaneous-total-and-speciation-analysis-of-volatile-metal-loid-s-in-gas-and-liquefied-gas-samples
#11
Laura Freije-Carrelo, Mariella Moldovan, Jose Ignacio Garcia-Alonso, Thuy Diep Thanh Vo, Jorge Ruiz Encinar
Although analysis of metals and metalloids, such as arsenic, is widely spread in many different fields, their analysis in gas and liquefied gas samples is still a challenge. A new GC-ICP-MS set up has been developed for their simultaneous total and speciation analysis in gas and liquefied gas samples without the need of a preconcentration step. An arsine in nitrogen standard was used for optimization and evaluation of the system. Good linearity and detection limits in the very low ppt level for both total and speciation analyses were found...
April 25, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28440728/characterization-of-chemical-contaminants-generated-by-a-desktop-fused-deposition-modeling-3-dimensional-printer
#12
Aleksandr B Stefaniak, Ryan F LeBouf, Jinghai Yi, Jason Ham, Timothy Nurkewicz, Diane E Schwegler-Berry, Bean T Chen, J Raymond Wells, Matthew G Duling, Robert B Lawrence, Stephen B Martin, Alyson R Johnson, M Abbas Virji
Printing devices are known to emit chemicals into the indoor atmosphere. Understanding factors that influence release of chemical contaminants from printers is necessary to develop effective exposure assessment and control strategies. In this study, a desktop fused deposition modeling (FDM) 3-D printer using acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA) filaments and two monochrome laser printers were evaluated in a 0.5 m(3) chamber. During printing, chamber air was monitored for vapors using a real-time photoionization detector (results expressed as isobutylene equivalents) to measure total volatile organic compound (TVOC) concentrations, evacuated canisters to identify specific VOCs by off-line gas chromatography-mass spectrometry (GC-MS) analysis, and liquid bubblers to identify carbonyl compounds by GC-MS...
April 25, 2017: Journal of Occupational and Environmental Hygiene
https://www.readbyqxmd.com/read/28439964/global-and-targeted-metabolomics-of-synovial-fluid-discovers-special-osteoarthritis-metabolites
#13
Kaidi Zheng, Shanmin Ni, Huaijun Chen, Shenmin Lou, Mengting Hu, Li Sun, Xinyu Yang
PURPOSE: To identify special metabolites in synovial fluid of osteoarthritis (OA) via a metabolomics approach. METHOD: Synovial fluid of 35 participants (25 OA patients and 10 controls) was detected by GC-TOF/MS and multivariate data analysis was applied to analyze correlation among the observations. Different metabolites were screened by VIP value (VIP > 1), student t test (p < 0.05), and fold change (fold > 1.5), and verified with the standard metabolites in the synovial fluid of 24 OA patients and 11 controls by LC/MS...
April 25, 2017: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
https://www.readbyqxmd.com/read/28439279/metabolic-investigation-of-phelipanche-aegyptiaca-reveals-significant-changes-during-developmental-stages-and-in-its-different-organs
#14
Noam Nativ, Yael Hacham, Joseph Hershenhorn, Evgenia Dor, Rachel Amir
Phelipanche aegyptiaca Pers. is a root holoparasitic plant considered to be among the most destructive agricultural weeds worldwide. In order to gain more knowledge about the metabolic profile of the parasite during its developmental stages, we carried out primary metabolic and lipid profiling using GC-MS analysis. In addition, the levels of amino acids that incorporate into proteins, total protein in the albumin fraction, nitrogen, reduced sugars, and phenols were determined. For the assays, the whole plants from the four developmental stages-tubercle, pre-emergent shoot, post-emergent shoot, and mature flowering plants-were taken...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28438317/a-novel-chromatographic-approach-to-distinguish-gram-positive-from-gram-negative-bacteria-using-exogenous-volatile-organic-compound-metabolites
#15
Susana Ramírez-Guízar, Hannah Sykes, John D Perry, Edward C Schwalbe, Stephen P Stanforth, Ma Cristina I Perez-Perez, John R Dean
This paper utilized L-alanine aminopeptidase activity as a useful approach to distinguish between Gram-negative and Gram-positive bacteria. This was done using two enzyme substrates, specifically 2-amino-N-phenylpropanamide and 2-amino-N-(4-methylphenyl)propanamide which liberated the volatile compounds aniline and p-toluidine, respectively. Two complementary analytical techniques have been used to identify and quantify the VOCs, specifically static headspace multicapillary column gas chromatography ion mobility spectrometry (SHS-MCC-GC-IMS) and headspace solid phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS)...
April 12, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28434710/shifting-the-paradigm-in-gas-chromatography-mass-spectrometry-pesticide-analysis-using-high-resolution-accurate-mass-spectrometry
#16
S Uclés, A Uclés, A Lozano, M J Martínez Bueno, A R Fernández-Alba
In the last 10 years, the majority of the pesticide food control laboratories moved from GC-MS to GC-MS/MS as the preferred analytical technique to address GC amenable compounds. The main reason for this change was the negative impact on the single stage GC-MS analysis caused by the interference from coeluting matrix compounds. The new development of gas chromatography coupled to high resolution accurate mass spectrometry (GC-HRAMS) provides opportunities to overcome such matrix interferences as a result of its much higher selectivity; allowing laboratories to carry out full-scan analysis covering the most exigent analytical performance criteria...
April 14, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28434709/target-analysis-of-tert-butyldimethylsilyl-derivatives-of-nerve-agent-hydrolysis-products-by-selectable-one-dimensional-or-two-dimensional-gas-chromatography-mass-spectrometry
#17
Yasuo Seto, Masumi Tachikawa, Mieko Kanamori-Kataoka, Kikuo Sasamoto, Nobuo Ochiai
A target analysis method for the sensitive and discriminative determination of the nerve agent hydrolysis products alkyl methylphosphonic acids as their tert-butyldimethylsilyl (TBDMS) derivatives was developed using a combination of selectable one- and two-dimensional ((1)D/(2)D) GC-MS, and applied to the analysis of samples with significant interfering matrices. After sample drying, the alkylmethylphosphonic acids and methylphosphonic acid (MPA) were converted to TBDMS derivatives by addition of N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide with heating, and subjected to (1)D/(2)D GC-MS...
April 13, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28433638/metabolomic-analysis-for-combined-hepatotoxicity-of-chlorpyrifos-and-cadmium-in-rats
#18
Ming-Yuan Xu, Pan Wang, Ying-Jian Sun, Yi-Jun Wu
Pesticides and heavy metals are widespread environmental pollutants. Although the acute toxicity of organophosphorus pesticide chlorpyrifos (CPF) and toxic heavy metal cadmium (Cd) is well characterized, the combined toxicity of CPF and Cd, especially the hepatotoxicity of the two chemicals with long-term exposure at a low dose, remained unclear. In this study, we investigated the toxicity in the liver of rats upon subchronic exposure to CPF and Cd at environmentally relevant doses. Rats were given three different doses (1/135 LD50, 1/45 LD50 and 1/15 LD50) of CPF and Cd as well as their mixtures by oral gavage for 90 days...
April 19, 2017: Toxicology
https://www.readbyqxmd.com/read/28433435/fabric-phase-sorptive-extraction-as-a-reliable-tool-for-rapid-screening-and-detection-of-freshness-markers-in-oranges
#19
M Aznar, S Úbeda, C Nerin, A Kabir, K G Furton
A simple, fast and sensitive analyte extraction method based on fabric phase sorptive extraction (FPSE) followed by gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC-QTOF-MS) analysis was developed for the analysis of 12 volatile compounds that represent most of the principal chemical families possessing different polarities and volatilities. Five FPSE media coated with different sol-gel sorbent chemistries having different polarities and selectivities were studied: long chain poly(dimethylsiloxane) (PDMS), short chain poly(tetrahydrofuran) (PTHF), Carbowax 20M (CW20M), short chain poly(dimethyl siloxane) (SC PDMS) and polyethylene glycol-polypropylene glycol-polyethylene glycol triblock copolymer (PEG-PPG-PEG)...
April 8, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28433159/glucuronoarabinoxylans-as-major-cell-walls-polymers-from-young-shoots-of-the-woody-bamboo-phyllostachys-aurea
#20
Víctor Martín Zelaya, Paula Virginia Fernández, Andrea Susana Vega, Anita Ida Mantese, Ana Ailén Federico, Marina Ciancia
Young shoots of Phyllostachys aurea showed glucuronoarabinoxylans (GAX) as the major hemicellulosic components, being extracted in major amounts with 1M KOH (ratio Xyl:Ara:GlcA, 100:67:8), but also with water, showing a broad structural variability. Mixed linkage glucans were also present, but in minor amounts, mostly concentrated in the 4M KOH extracts, while pectin polymers were very scarce. Arabinogalactan proteins were an important part of water extracts, determined by the presence of the typical arabinogalactan structures (3- and 6-linked Gal p; terminal and 5-linked Ara f), in addition to small amounts of hydroxyproline (2-3% of total protein) and positive reaction to Yariv's reagent...
July 1, 2017: Carbohydrate Polymers
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