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https://www.readbyqxmd.com/read/28454030/pesticide-impact-study-in-the-peri-urban-horticultural-area-of-gran-la-plata-argentina
#1
Tomás M Mac Loughlin, Leticia Peluso, Damián J G Marino
Vegetable production systems are characterized by intense pesticide use, yet the effects on the surrounding environment are largely unknown and need to be studied. Given this knowledge gap, the objective of this work is to determine the impact of horticulture on a representative watercourse by conducting an integrated study of the occurrence and concentration of pesticides in bottom sediments and their relation to lethal and sublethal effects on benthic fauna. Two sampling campaigns were conducted during seasons of low and high pesticide application in five sites along the Carnaval creek, located in the peri-urban area of La Plata City (Buenos Aires, Argentina)...
April 25, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28447619/little-cigars-are-more-toxic-than-cigarettes-and-uniquely-change-the-airway-gene-and-protein-expression
#2
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/28447506/anti-inflammatory-and-gastroprotective-potential-of-leaf-essential-oil-of-cinnamomum-glanduliferum-in-ethanol-induced-rat-experimental-gastritis
#3
Samar S Azab, Gehad A Abdel Jaleel, Omayma A Eldahshan
CONTEXT: Nothing could be found in the literature concerning Cinnamomum glanduliferum (Wall) Meissn (Lauraceae) bark (CG) in Egypt. OBJECTIVE: To investigate CG volatile oil chemically and its anti-inflammatory and gastroprotective effects. MATERIALS AND METHODS: Essential oils were investigated by GC-MS. Leaves oil was assessed at doses of 250, 500 and 1000 mg/kg for its anti-inflammatory effect against carrageenan-induced rat oedema model...
December 2017: Pharmaceutical Biology
https://www.readbyqxmd.com/read/28447255/phenolic-compounds-volatiles-and-antioxidant-capacity-of-white-myrtle-berry-liqueurs
#4
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/28446195/mature-leaf-concentrate-of-sri-lankan-wild-type-carica-papaya-linn-modulates-nonfunctional-and-functional-immune-responses-of-rats
#5
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/28445860/brephedrone-a-new-psychoactive-substance-seized-in-brazil
#6
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
#7
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
#8
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/28444322/fumigant-activity-of-sweet-orange-essential-oil-fractions-against-red-imported-fire-ants-hymenoptera-formicidae
#9
Wei Hu, Ning Zhang, Hongli Chen, Balian Zhong, Aixue Yang, Fan Kuang, Zhigang Ouyang, Jiong Chun
Sweet orange oil fractions were prepared by molecular distillation of cold-pressed orange oil from sample A (Citrus sinensis (L.) 'Hamlin' from America) and sample B (Citrus sinensis Osbeck 'Newhall' from China) respectively, and their fumigant activities against medium workers of red imported fire ants (Solenopsis invicta Buren) were investigated. The volatile composition of the orange oil fractions was identified and quantified using GC-MS. Fractions from sample A (A1, A2, and A3) contained 23, 37, and 48 chemical constituents, and fractions from sample B (B1, B2, and B3) contained 18, 29, and 26 chemical constituents, respectively...
April 21, 2017: Journal of Economic Entomology
https://www.readbyqxmd.com/read/28443078/phytochemical-characterization-of-terminalia-catappa-linn-extracts-and-their-antifungal-activities-against-candida-spp
#10
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
#11
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
#12
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
#13
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
#14
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
#15
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
#16
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/28440728/characterization-of-chemical-contaminants-generated-by-a-desktop-fused-deposition-modeling-3-dimensional-printer
#17
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/28439279/metabolic-investigation-of-phelipanche-aegyptiaca-reveals-significant-changes-during-developmental-stages-and-in-its-different-organs
#18
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
#19
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/28438040/semi-preparative-hplc-purification-of-%C3%AE-tocotrienol-%C3%AE-t3-from-elaeis-guineensis-jacq-and-bixa-orellana-l-and-evaluation-of-its-in-vitro-anticancer-activity-in-human-a375-melanoma-cells
#20
Giangiacomo Beretta, Fabrizio Gelmini, Fabrizio Fontana, Roberta Manuela Moretti, Marina Montagnani Marelli, Patrizia Limonta
In this work, we report a rapid and convenient HPLC-UV-DAD method for the isolation of δ-T3 on semi-preparative scale from two different vitamin E rich processed, commercially available products obtained from the fruits of Elaeis guineensis Jacq. (oil palm) and from the seeds of Bixa orellana L. (achiote tree). Chromatography was run using reverse phase (RP) C-18 columns and HPLC-grade acetonitrile as mobile phase. The purity of the isolated δ-T3, assessed by GC-MS and (1)H NMR was above 98%. The δ-T3 cytotoxic activity found in vitro against the proliferation of human A375 melanoma cells compared to that of the other δ-T3 free tocols mixture suggest its primary role in the experimental anticancer activity observed for palm oil derived products...
April 24, 2017: Natural Product Research
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