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https://www.readbyqxmd.com/read/29340521/organic-solvent-exposure-and-contrast-sensitivity-comparing-men-and-women
#1
A R Oliveira, A A Campos Neto, M J O de Andrade, P C B de Medeiros, N A Dos Santos
The goal of this study was to compare the visual contrast sensitivity (CS) of men and women exposed and not exposed to organic solvents. Forty-six volunteers of both genders aged between 18 and 41 years (mean±SD=27.72±6.28) participated. Gas station attendants were exposed to gas containing 46.30 ppm of solvents at a temperature of 304±274.39 K, humidity of 62.25±7.59% and ventilation of 0.69±0.46 m/s (a passive gas chromatography-based sampling method was used considering the microclimate variables). Visual CS was measured via the psychophysical method of two-alternative forced choice using vertical sinusoidal gratings with spatial frequencies of 0...
January 11, 2018: Brazilian Journal of Medical and Biological Research, Revista Brasileira de Pesquisas Médicas e Biológicas
https://www.readbyqxmd.com/read/29339821/cigarette-smoking-is-associated-with-an-altered-vaginal-tract-metabolomic-profile
#2
T M Nelson, J C Borgogna, R D Michalek, D W Roberts, J M Rath, E D Glover, J Ravel, M D Shardell, C J Yeoman, R M Brotman
Cigarette smoking has been associated with both the diagnosis of bacterial vaginosis (BV) and a vaginal microbiota lacking protective Lactobacillus spp. As the mechanism linking smoking with vaginal microbiota and BV is unclear, we sought to compare the vaginal metabolomes of smokers and non-smokers (17 smokers/19 non-smokers). Metabolomic profiles were determined by gas and liquid chromatography mass spectrometry in a cross-sectional study. Analysis of the 16S rRNA gene populations revealed samples clustered into three community state types (CSTs) ---- CST-I (L...
January 16, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29339749/volatile-molecules-from-bronchoalveolar-lavage-fluid-can-rule-in-pseudomonas-aeruginosa-and-rule-out-staphylococcus-aureus-infections-in-cystic-fibrosis-patients
#3
Mavra Nasir, Heather D Bean, Agnieszka Smolinska, Christiaan A Rees, Edith T Zemanick, Jane E Hill
Respiratory infections caused by Pseudomonas aeruginosa and Staphylococcus aureus are the leading cause of morbidity and mortality in cystic fibrosis (CF) patients. The authors aimed to identify volatile biomarkers from bronchoalveolar lavage (BAL) samples that can guide breath biomarker development for pathogen identification. BAL samples (n = 154) from CF patients were analyzed using two-dimensional gas chromatography time-of-flight mass spectrometry. Random Forest was used to select suites of volatiles for identifying P...
January 16, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29339306/morphological-changes-of-bacterial-cells-upon-exposure-of-silver-silver-chloride-nanoparticles-synthesized-using-agrimonia-pilosa
#4
Maheshkumar Prakash Patil, Yong Bae Seo, Gun-Do Kim
Facile, eco-friendly synthesis of metal nanoparticles has been proposed as a cost effective method. In the present study, we propose the facile synthesis of silver-silver chloride (Ag-AgCl) nanoparticles (NPs) using the medicinally important Agrimonia pilosa plant extract without addition of capping or stabilizing agents. The Ag-AgCl NPs synthesis was observed at 40 °C after 10 min incubation; the synthesis of Ag-AgCl NPs was indicated by color change and confirmed by UV-vis spectroscopic peak at 454 nm...
January 12, 2018: Microbial Pathogenesis
https://www.readbyqxmd.com/read/29337873/two-novel-proline-containing-catechin-glucoside-from-water-soluble-extract-of-codonopsis-pilosula
#5
Fu-Ying Qin, Li-Zhi Cheng, Yong-Ming Yan, Bao-Hua Liu, Yong-Xian Cheng
Choushenflavonoids A (1) and B (2), two unusual proline-containing catechin glucosides, were isolated from the roots of Codonopsis pilosula cultivated in a high-altitude location of Yunnan province. Their structures were determined by spectroscopic data and chemical methods. Specifically, the absolute configuration of glucose residue in 1 and 2 was assigned by acid hydrolysis followed by derivatization and gas chromatography (GC) analysis. In addition, biological evaluation of 1 and 2 against Sirtuin 1 (SIRT1) was carried out...
January 16, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29337687/comparison-of-the-solid-phase-and-liquid-liquid-extraction-methods-for-methadone-determination-in-human-serum-and-whole-blood-samples-using-gas-chromatography-mass-spectrometry
#6
Maja Veršić Bratinčević, Tanja Visković, Davorka Sutlović
The aim of this study was to determine the optimal biological sample and the optimal extraction technique for monitoring methadone concentrations in biological samples. We analysed methadone in serum and whole blood samples using gas chromatography/mass spectrometry (GC/MS). Before analysis, we compared five solid-phase extraction (SPE) and two liquid-liquid extraction (LLE) methods and determined that SPE with Supelco LC-18 in serum yielded the best extraction efficiency. The limit of detection was 10 ng mL-1 and the limit of quantification 25 ng mL-1...
December 20, 2017: Arhiv za Higijenu Rada i Toksikologiju
https://www.readbyqxmd.com/read/29337656/a-review-of-methodology-for-the-analysis-of-pyrethrin-and-pyrethroid-residues-in-food-of-animal-origin
#7
S Tuck, A Furey, S R H Crooks, M Danaher
Pyrethrin and pyrethroid pesticides are commonly used in crop protection and animal health, to control pests. As a result, they can potentially transfer into food if good agricultural practice is not followed or even due to accidental contamination. The analysis of these compounds has been widely reported in crops and the environment. However, the analysis of pyrethrin and pyrethroids has not been reported frequently in foods of animal origin, particularly animal tissues. The focus of this review is to report on pyrethrin and pyrethroid analysis including key aspects such as chemistry, choice of target matrix, sample preparation, chemical analysis, legislation and method validation...
January 16, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29337366/replenishment-of-docosahexaenoic-acid-dha-in-dietary-n-3-deficient-mice-fed-dha-in-triglycerides-or-phosphatidylcholines-after-weaning
#8
Dan-Dan Wang, Fang Wu, Min Wen, Lin Ding, Lei Du, Chang-Hu Xue, Jie Xu, Yu-Ming Wang
Previous studies have shown that DHA in triglyceride (TG) and phosphatidylcholine (PC) forms are different in their bioavailability. The aim of this study was to investigate the comparative effects of DHA-TG and DHA-PC on tissue DHA accretion in dietary n-3 polyunsaturated fatty acid deficient (n-3 Def) mice. The mice were fed with n-3 Def diet containing DHA-TG or DHA-PC (5 g/kg diet) for 2, 4, 7, or 14 d after weaning, respectively. The DHA levels in the cortex, liver, testis, and erythrocytes were analyzed by gas chromatography...
January 16, 2018: Journal of Food Science
https://www.readbyqxmd.com/read/29336990/failure-of-intracardiac-pacing-after-fatal-propafenone-overdose-a-case-report
#9
Ivan Zeljković, Nikola Bulj, Matea Kolačević, Vedran Čabrilo, Diana Delić Brkljačić, Šime Manola
BACKGROUND: Propafenone is a sodium-channel blocker, class IC antiarrhythmic drug, frequently used to manage supraventricular dysrhythmias, especially atrial fibrillation. We report a self mono-intoxication with propafenone. CASE REPORT: A 68-year-old woman presented with a decreased level of consciousness, hypotension, and electrocardiogram showing QRS widening with atrial asystole and extreme bradycardia < 20 beats/min. After initial stabilization with transcutaneous pacing, laboratory findings detected normal electrolyte ranges and metabolic acidosis, and her medical history revealed availability of propafenone due to paroxysmal atrial fibrillation and depressive syndrome, which led to the suspicion of intoxication...
January 11, 2018: Journal of Emergency Medicine
https://www.readbyqxmd.com/read/29336664/grab-and-passive-sampling-applied-to-pesticide-analysis-in-the-s%C3%A3-o-louren%C3%A3-o-river-headwater-in-campo-verde-mt-brazil
#10
André Berton, Michelle F Brugnera, Eliana F G C Dores
In this study, the quality of surface water in the headwaters of São Lourenço River in Mato Grosso, Brazil, was evaluated in relation to contamination by pesticides. For this purpose, samples were collected between December 2015 and June 2016 by grab sampling and by passive sampling using an integrative polar organic compound sampler installed in the field during four 14-day cycles between March and June 2016. The analyses were performed by gas chromatography (CG/MS) and by liquid chromatography (UPLC-MS/MS)...
January 16, 2018: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/29335813/organic-acidurias-in-adults-late-complications-and-management
#11
Ali Tunç Tuncel, Nikolas Boy, Marina A Morath, Friederike Hörster, Ulrike Mütze, Stefan Kölker
Organic acidurias (synonym, organic acid disorders, OADs) are a heterogenous group of inherited metabolic diseases delineated with the implementation of gas chromatography/mass spectrometry in metabolic laboratories starting in the 1960s and 1970s. Biochemically, OADs are characterized by accumulation of mono-, di- and/or tricarboxylic acids ("organic acids") and corresponding coenzyme A, carnitine and/or glycine esters, some of which are considered toxic at high concentrations. Clinically, disease onset is variable, however, affected individuals may already present during the newborn period with life-threatening acute metabolic crises and acute multi-organ failure...
January 15, 2018: Journal of Inherited Metabolic Disease
https://www.readbyqxmd.com/read/29335416/lack-of-pronounced-changes-in-the-expression-of-fatty-acid-handling-proteins-in-adipose-tissue-and-plasma%C3%A2-of-morbidly-obese-humans
#12
Ewa Anna Grzegorczyk, Ewa Harasim-Symbor, Bartlomiej Lukaszuk, Dorota Harasiuk, Barbara Choromanska, Piotr Mysliwiec, Malgorzata Zendzian-Piotrowska, Adrian Chabowski
BACKGROUND/OBJECTIVES: Fatty acid handling proteins are involved in the process of accumulation of lipids in different fat tissue depots. Thus, the aim of the study was to estimate the expression of both fatty acid transport and binding proteins in the subcutaneous (SAT) and visceral adipose tissue (VAT) of patients with morbid obesity without metabolic syndrome, as well as the plasma concentrations of these transporters. SUBJECTS/METHODS: Protein (Western blotting) and mRNA (Real-time PCR) expression of selected fatty acid handling proteins was assessed in the visceral and subcutaneous adipose tissue of 30 patients with morbid obesity...
January 15, 2018: Nutrition & Diabetes
https://www.readbyqxmd.com/read/29334335/simultaneous-formation-of-polycyclic-aromatic-hydrocarbons-pahs-and-heterocyclic-aromatic-amines-hcas-in-gas-grilled-beef-satay-at-different-temperatures
#13
A K Nor Hasyimah, S Jinap, M Sanny
This study investigated the simultaneous formation of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines (HCAs) in gas-grilled beef satay at different temperatures (150°C, 200°C, 250°C, 300°C, and 350°C). Solid-phase extraction (SPE) was used for sample clean-up. Fifteen PAHs were determined using high performance liquid chromatography with fluorescence detection (HPLC-FLD) and nine HCAs were quantified using liquid chromatography tandem-mass spectrometry (LC-MS/MS) with a gradient programme...
January 15, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29334019/chemical-stabilization-of-polymers-implications-for-dermal-exposure-to-additives
#14
N Bartsch, M Girard, L Schneider, V Van De Weijgert, A Wilde, O Kappenstein, B Vieth, C Hutzler, A Luch
Technical benefits of additives in polymers stand in marked contrast to their associated health risks. Here, a multi-analyte method based on gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) was developed to quantify polymer additives in complex matrices such as low-density polyethylene (LDPE) and isolated human skin layers after dermal exposure ex vivo. That way both technical aspects and dermal exposure were investigated. The effects of polymer additivation on the material were studied using the example of LDPE...
January 15, 2018: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
https://www.readbyqxmd.com/read/29333891/therapeutic-potential-of-zataria-multiflora-boiss-in-treatment-of-irritable-bowel-syndrome-ibs
#15
Mohaddese Mahboubi
Irritable Bowel syndrome (IBS), the most common chronic functional gastrointestinal disorder, is categorized as IBS-C and IBS-D, which are equivalent to Ghoolenj Rihi and Maghs Rihi in Iranian traditional medicine. One of the main applications of Zataria multiflora Boiss in traditional medicine is its efficacy in the gastrointestinal tract with symptoms such as IBS. The aim of this study was to evaluate the efficacy of Zataria multiflora essential oil in management of IBS. We used all the accessible references (electronic and published books, theses, and reports) to write this article...
January 15, 2018: Journal of Dietary Supplements
https://www.readbyqxmd.com/read/29333042/gas-chromatography-mass-spectrometry-profiling-in-methanolic-and-ethyl-acetate-root-and-stem-extract-of-corbichonia-decumbens-forssk-exell-from-thar-desert-of-rajasthan-india
#16
Sunita Arora, Manju Saini
Background: Corbichonia decumbens (Forssk.) Exell (Molluginaceae), recently has moved to Lophiocarpaceae as per angiospermic plant group (APG) III system, is an annual or short-lived, dwarf, glabrous subshrub, prefers to grow on rocky places and on sand-stones in dry, hot areas of Rajasthan. This is the potential plant with medicinal properties. Vegetative organs under study show antioxidant, anti-inflammatory, antiulcer, antimicrobial, and antinociception activity. Objective: This study was carried out to identify the phytoconstituents present in the methanolic and ethyl-acetate extract of root and stem of C...
December 2017: Pharmacognosy Research
https://www.readbyqxmd.com/read/29332575/protective-role-of-italian-juglans-regia-l-nut-ethanolic-extract-in-human-keratinocytes-under-oxidative-and-inflammatory-stress
#17
Cinzia Calcabrini, Umberto Mancini, Roberta De Bellis, Alessandra Frati, Anna Rita Mastrogiacomo, Giosue Annibalini, Piero Sestili, Luigi Cucchiarini, Vilberto Stocchi, Lucia Potenza
OBJECTIVE: In this research, fatty acid profile and polyphenolic content of an ethanolic extract of walnut from Juglans regia L. collected in Central Italy, were performed. The potential antioxidant and anti-inflammatory effects of the extract were investigated in the human keratinocytes cell line. METHODS: Fatty acid profile was determined by gas chromatography/mass spectrometry analysis, total phenolic content by Folin-Ciocalteu method and aluminum chloride colorimetric method was used for determination of total flavonoids...
January 12, 2018: Current Pharmaceutical Biotechnology
https://www.readbyqxmd.com/read/29331743/preliminary-investigation-of-human-exhaled-breath-for-tuberculosis-diagnosis-by-multidimensional-gas-chromatography-time-of-flight-mass-spectrometry-and-machine-learning
#18
Marco Beccaria, Theodore R Mellors, Jacky S Petion, Christiaan A Rees, Mavra Nasir, Hannah K Systrom, Jean W Sairistil, Marc-Antoine Jean-Juste, Vanessa Rivera, Kerline Lavoile, Patrice Severe, Jean W Pape, Peter F Wright, Jane E Hill
Tuberculosis (TB) remains a global public health malady that claims almost 1.8 million lives annually. Diagnosis of TB represents perhaps one of the most challenging aspects of tuberculosis control. Gold standards for diagnosis of active TB (culture and nucleic acid amplification) are sputum-dependent, however, in up to a third of TB cases, an adequate biological sputum sample is not readily available. The analysis of exhaled breath, as an alternative to sputum-dependent tests, has the potential to provide a simple, fast, and non-invasive, and ready-available diagnostic service that could positively change TB detection...
January 4, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29330963/metal-organic-framework-based-in-syringe-solid-phase-extraction-for-the-on-site-sampling-of-polycyclic-aromatic-hydrocarbons-from-environmental-water-samples
#19
Xiaoqiong Zhang, Peiyi Wang, Qiang Han, Hengzhen Li, Tong Wang, Mingyu Ding
In-syringe solid-phase extraction is a promising sample pretreatment method for the on-site sampling of water samples because of its outstanding advantages of portability, simple operation, short extraction time and low cost. In this work, a novel in-syringe solid-phase extraction device using metal-organic frameworks as the adsorbent was fabricated for the on-site sampling of polycyclic aromatic hydrocarbons from environmental waters. Trace polycyclic aromatic hydrocarbons were effectively extracted through the self-made device followed by gas chromatography with mass spectrometry analysis...
January 13, 2018: Journal of Separation Science
https://www.readbyqxmd.com/read/29330898/determination-of-phthalate-esters-in-soil-using-a-quick-easy-cheap-effective-rugged-and-safe-method-followed-by-gc-ms
#20
Qianjun Liu, Di Chen, Jiyuan Wu, Guangcai Yin, Qintie Lin, Min Zhang, Huawen Hu
A quick, easy, cheap, effective, rugged, and safe procedure was designed to extract pesticide residues from fruits and vegetables with a high percentage of water. It has not been used extensively for the extraction of phthalate esters from sediments, soils and sludges. In this work, this procedure was combined with gas chromatography with mass spectrometry to determine 16 selected phthalate esters in soil. The extraction efficiency of the samples was improved by ultrasonic extraction and dissolution of the soil samples in ultra-pure water, which promoted the dispersion of the samples...
January 13, 2018: Journal of Separation Science
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