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https://www.readbyqxmd.com/read/28448812/effect-of-exposure-to-p-p%C3%A2-dde-during-the-first-half-of-pregnancy-in-the-maternal-thyroid-profile-of-female-residents-in-a-mexican-floriculture-area
#1
José Ángel Hernández-Mariano, Luisa Torres-Sánchez, Susana Bassol-Mayagoitia, Maria Consuelo Escamilla-Nuñez, Mariano E Cebrian, Érika Adriana Villeda-Gutiérrez, Guadalupe López-Rodríguez, Eunice Elizabeth Félix-Arellano, Julia Blanco-Muñoz
BACKGROUND: Dichlorodiphenyldichloroethene (p,p´-DDE), the main metabolite of dichlorodiphenyltrichloroethane (DDT), has been associated with changes in human thyroid hormone levels. Maternal thyroid hormones are essential for adequate fetal neurodevelopment during the first half of pregnancy. OBJECTIVE: To evaluate the association between maternal p,p´-DDE concentration and the maternal thyroid profile during the first half of pregnancy. MATERIALS AND METHODS: We analyzed the information of 430 pregnant women from a Mexican floriculture area, with a gestational age ≤16 weeks...
April 24, 2017: Environmental Research
https://www.readbyqxmd.com/read/28448475/formulation-characterization-and-properties-of-hemp-seed-oil-and-its-emulsions
#2
Veronika Mikulcová, Věra Kašpárková, Petr Humpolíček, Leona Buňková
The formulation, characterization, and anticipated antibacterial properties of hemp seed oil and its emulsions were investigated. The oil obtained from the seeds of Cannabis sativa L. in refined and unrefined form was characterized using iodine, saponification, acid values, and gas chromatography, and was employed for the preparation of stable oil-in-water emulsions. The emulsions were prepared using pairs of non-ionic surfactants (Tween, Span). The effects of the emulsification method (spontaneous emulsification vs...
April 27, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28447993/synthesis-of-1-2-azaborines-and-the-preparation-of-their-protein-complexes-with-t4-lysozyme-mutants
#3
Hyelee Lee, Shih-Yuan Liu
We describe a general synthesis of 1,2-azaborines using standard air-free techniques and protein complex preparation with T4 lysozyme mutants by vapor diffusion. Oxygen- and moisture-sensitive compounds are prepared and isolated under an inert atmosphere (N2) using either a vacuum gas manifold or a glove box. As an example of azaborine synthesis, we demonstrate the synthesis and purification of the volatile N-H-B-ethyl-1,2-azaborine by a five-step sequence involving distillation and column chromatography for the isolation of products...
March 25, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28447619/little-cigars-are-more-toxic-than-cigarettes-and-uniquely-change-the-airway-gene-and-protein-expression
#4
Arunava Ghosh, Sabri H Abdelwahab, Steven L Reeber, Boris Reidel, Abigail J Marklew, Andrew J Garrison, Shernita Lee, Hong Dang, Amy H Herring, Gary L Glish, Mehmet Kesimer, Robert Tarran
Little cigars (LCs) are regulated differently than cigarettes, allowing them to be potentially targeted at youth/young adults. We exposed human bronchial epithelial cultures (HBECs) to air or whole tobacco smoke from cigarettes vs. LCs. Chronic smoke exposure increased the number of dead cells, lactate dehydrogenase release, and interleukin-8 (IL-8) secretion and decreased apical cilia, cystic fibrosis transmembrane conductance regulator (CFTR) protein levels, and transepithelial resistance. These adverse effects were significantly greater in LC-exposed HBECs than cigarette exposed cultures...
April 27, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28447255/phenolic-compounds-volatiles-and-antioxidant-capacity-of-white-myrtle-berry-liqueurs
#5
Gabriele Serreli, Igor Jerković, Katarzyna Angelika Gil, Zvonimir Marijanović, Viviana Pacini, Carlo Ignazio Giovanni Tuberoso
The aim of this research was to evaluate the antioxidant capacity and physical-chemical characteristics of commercial white myrtle berry (Myrtus communis L. var. leucocarpa DC) liqueur (WMBL). The total phenolic (TP) content was measured spectrophotometrically, applying a modified Folin-Ciocalteu's method, and phenolic compounds were identified by high-performance liquid chromatography (HPLC) coupled with electrospray mass spectrometry, and quantified by HPLC coupled with ultraviolet/visible detection. The antioxidant capacities were evaluated by FRAP, CUPRAC, DPPH(•), and ABTS(•+) assays...
April 26, 2017: Plant Foods for Human Nutrition
https://www.readbyqxmd.com/read/28446501/dietary-long-chain-fatty-acids-and-carbohydrate-biomarker-evaluation-in-a-controlled-feeding-study-in-participants-from-the-women-s-health-initiative-cohort
#6
Xiaoling Song, Ying Huang, Marian L Neuhouser, Lesley F Tinker, Mara Z Vitolins, Ross L Prentice, Johanna W Lampe
Background: Biomarkers of macronutrient intake are lacking. Controlled human feeding studies that preserve the normal variation in nutrient and food consumption are necessary for the development and validation of robust nutritional biomarkers.Objective: We aimed to assess the utility of serum phospholipid fatty acids (PLFAs) as biomarkers of dietary intakes of fatty acids, total fat, and carbohydrate.Design: We used an individualized controlled feeding study in which 153 postmenopausal women from the Women's Health Initiative (WHI) were provided with a 2-wk controlled diet that mimicked each individual's habitual food intake...
April 26, 2017: American Journal of Clinical Nutrition
https://www.readbyqxmd.com/read/28446328/combined-gc-and-uhplc-hr-ms-based-metabolomics-to-analyze-durable-anti-fungal-resistance-processes-in-cereals
#7
Rahel Bucher, Daniel Veyel, Lothar Willmitzer, Simon Krattinger, Beat Keller, Laurent Biglera
Introduction of durable resistance genes in crops is an important strategy to prevent yield loss caused by pathogens. The durable multi-pathogen resistance gene Lr34 originating from wheat is widely used in breeding, and is functionally transferable to barley and rice. The molecular resistance mechanism of Lr34, encoding for an adenosine triphosphate-binding cassette transporter, is not known yet. To understand the molecular function and the defense response of durable disease resistance in cereals, the metabolic response of Lr34 was investigated in, except for the Lr34 gene, genetically identical lines of barley, rice and wheat...
April 26, 2017: Chimia
https://www.readbyqxmd.com/read/28446195/mature-leaf-concentrate-of-sri-lankan-wild-type-carica-papaya-linn-modulates-nonfunctional-and-functional-immune-responses-of-rats
#8
Chanika Dilumi Jayasinghe, Dinara S Gunasekera, Nuwan De Silva, Kithmini Kawya Mandakini Jayawardena, Preethi Vidya Udagama
BACKGROUND: The leaf concentrate of Carica papaya is a traditionally acclaimed immunomodulatory remedy against numerous diseases; nonetheless comprehensive scientific validation of this claim is limited. The present study thus investigated the immunomodulatory potential of Carica papaya mature leaf concentrate (MLCC) of the Sri Lankan wild type cultivar using nonfunctional and functional immunological assays. METHODS: Wistar rats (N = 6/ group) were orally gavaged with 3 doses (0...
April 26, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28444854/analysis-of-organic-components-in-resin-modified-pulp-capping-materials-critical-considerations
#9
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
#10
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/28444593/decolourization-and-biodegradation-of-navy-blue-her-reactive-blue-171-dye-from-marasmius-sp-bbkav79
#11
Adiveppa B Vantamuri, Basappa B Kaliwal
White rot fungus Marasmius sp. BBKAV79 (GenBank accession number-KP455496, KP455497) exhibited decolourization and degradation of Navy blue HER dye (concentration 50 mg l(-l)) within 24 h under shaking condition. In the present study, various investigated parameters like initial dye concentration, pH, temperature, carbon and nitrogen sources were optimized to develop a faster decolourization process by Marasmius sp. BBKAV79. High-performance liquid chromatography, Fourier transform infrared spectroscopy and gas chromatography and mass spectroscopy analysis of the extracted product confirmed the biodegradation of Navy blue HER...
May 2017: 3 Biotech
https://www.readbyqxmd.com/read/28444188/gas-chromatography-mass-spectrometry-method-to-quantify-benzo-a-pyrene-in-tobacco-products
#12
Karl A Wagner, Chorng B Huang, Matt S Melvin, Regina Ballentine, Naren K Meruva, Jason W Flora
The USA Food and Drug Administration (FDA) established benzo[a]pyrene (B[a]P) as a harmful and potentially harmful constituent (HPHC) found in tobacco products. Tobacco manufacturers are required to report HPHC quantities to the FDA; however, there is currently no standardized method for determination of B[a]P in smokeless tobacco products (STPs). This work details a sensitive, selective and rapid method for the determination of B[a]P in STPs, cigarette filler and tobacco. Tobacco is extracted using methanol followed by solid-phase extraction and concentration prior to analysis by gas chromatography/mass spectrometry in the selected ion monitoring mode...
April 21, 2017: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/28443847/the-impact-of-dietary-sn-2-palmitic-triacylglycerols-in-combination-with-docosahexaenoic-acid-or-arachidonic-acid-on-lipid-metabolism-and-host-faecal-microbiota-composition-in-sprague-dawley-rats
#13
Jianchun Wan, Songyou Hu, Jörg J Jacoby, Jie Liu, Yaqiong Zhang, Liangli Lucy Yu
Sn-2 palmitic acid triacylglycerols (sn2PA fat) and polyunsaturated fatty acids are thought to influence the metabolic status and intestinal bacterial population of the host. In this study, the impact of sn2PA fat in combination with DHA or ARA in the diet on lipid metabolism in the liver and faecal microbiota composition were investigated in rats fed diets containing sn2PA fat, 90% sn2PA fat + 10% DHA oil (wt%), or 90% sn2PA fat + 10% ARA oil (wt%). Tissue fatty acid composition was measured using gas chromatography (GC), whereas the faecal microbial composition was assessed using 16S rRNA high-throughput sequencing technology...
April 26, 2017: Food & Function
https://www.readbyqxmd.com/read/28443843/atmospheric-pressure-soft-ionization-for-gas-chromatography-with-dielectric-barrier-discharge-ionization-mass-spectrometry-gc-dbdi-ms
#14
Mario F Mirabelli, Jan-Christoph Wolf, Renato Zenobi
In this study, a gas chromatography (GC) system was interfaced to a high-resolution Orbitrap mass spectrometer by means of an active capillary plasma ionization source, based on dielectric barrier discharge ionization (DBDI). This allowed highly efficient soft ionization of gas-phase, chromatographically resolved compounds at ambient pressure. Several pesticides and illicit drugs were analyzed, and the limits of detections (LODs) were as low as 30 pg mL(-1) for the GC-DBDI-MS coupling (corresponding to 60 fg on-column sensitivity) and 30 fg mL(-1) for SPME-GC-DBDI-MS...
April 26, 2017: Analyst
https://www.readbyqxmd.com/read/28443078/phytochemical-characterization-of-terminalia-catappa-linn-extracts-and-their-antifungal-activities-against-candida-spp
#15
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/28442657/structural-characterization-and-biological-activities-of-a-novel-polysaccharide-from-phyllanthus-emblica
#16
Zihan Zeng, Wenjie Lv, Yongshuai Jing, Zhiyan Chen, Liyan Song, Ting Liu, Rongmin Yu
A novel water-soluble polysaccharide named PEPW80-1, with a molecular mass of 4.7 kDa, was isolated from the pulp tissues of Phyllanthus emblica, and purified by sephadex G-100 column and sephacryl S-300 HR chromatography. The structural features of PEPW80-1 were investigated by a combination of acid hydrolysis, periodate oxidation-Smith degradation, methylation analysis, gas chromatography-mass spectrometry, scanning electron microscope, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy...
April 25, 2017: Drug Discoveries & Therapeutics
https://www.readbyqxmd.com/read/28442173/analysis-of-tar-compounds-and-quantification-of-naphthalene-from-thermal-treatment-of-household-biowaste
#17
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/28442132/gas-chromatography-with-diode-array-detection-in-series-with-flame-ionisation-detection
#18
Ronda Gras, Jim Luong, Robert A Shellie
We introduce a gas chromatography detection approach that uses diode array detection operated in series with flame ionisation detection and demonstrate the utility of the detection approach for determination of volatile organic compounds. Diode array detection brings ultraviolet - visible spectroscopy (over a range of 190-640nm) onto the capillary gas chromatography time-scale, where average peak widths of analytes are on the order of 3-5s. The non-destructive nature of the diode array detector affords serially-coupled flame ionisation detection...
April 12, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28442107/in%C3%A2-vitro-and-in%C3%A2-vivo-investigation-of-natural-compounds-from-seed-extract-of-mucuna-pruriens-lacking-l-dopa-for-the-treatment-of-erectile-dysfunction
#19
Natthachai Duangnin, Thanyaluck Phitak, Peraphan Pothacharoen, Prachya Kongtawelert
OBJECTIVE: To investigate the biological effects of the Mucuna pruriens (M. pruriens) seed extracts that lacked l-DOPA, which was formerly reported as the active ingredient, on erectile dysfunction (ED) both in vitro and in vivo. METHODS: Seed of M. pruriens plant that cultivated in Mae Taeng District, Chiang Mai Province, Thailand, was collected. Component of its seeds were extracted and isolated into 2 fractions using methanol, polar and nonpolar. Each fraction was investigated for phytochemicals using gas chromatography and mass spectroscopy and was screened for biological activity in vitro using three different cell lines...
March 2017: Asian Pacific Journal of Tropical Medicine
https://www.readbyqxmd.com/read/28441028/application-of-gc-ms-soft-ionization-for-isomeric-biological-compound-analysis
#20
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
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